Final Comment 

Response Document 

for the Regulatory 

Determination for 

Perchlorate 

(Categorized Public 

Comments) 
Office of Water (4607M) 

EPA 815-R-10- 005 

January 2011 

http://water.epa.gov/drink/
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Table of Contents

1. INTRODUCTION AND OVERVIEW ............................................................................................ 1

2. APPARENT MASS MAILING CAMPAIGNS .................................................................................. 4

Apparent Mass Mailing #1 - Physicians for Social Responsibility ....................................................... 4

Apparent Mass Mailing #2 - Physicians for Social Responsibility ....................................................... 4

Apparent Mass Mailing #3 Group Unidentified .................................................................................... 5

Apparent Mass Mailing #4 - Natural Resources Defense Council...................................................... 6

Apparent Mass Mailing #5 - Clean Water Fund/Clean Water Action ............................................... 7

Apparent Mass Mailing #6 - Earth Justice .............................................................................................. 7

Apparent Mass Mailing #7 – Group Unidentified ................................................................................ 8

Apparent Mass Mailing #8 - Food and Water Watch ........................................................................... 8

Apparent Mass Mailing #9 - Group Unidentified ................................................................................. 9

Apparent Mass Mailing #10 - Group Unidentified ............................................................................... 9

Apparent Mass Mailing #11 - Food and Water Watch ....................................................................... 10

3. COMMENTS AND EPA RESPONSES BY COMMENT CODE ...................................................... 12

EPA Comment Code: 1000 General Comments ................................................................................. 12

EPA Comment Code: 1100 SDWA requirements and the CCL and Regulatory 

Determinations process .................................................................................................................. 19

EPA Comment Code: 1300 Length of the comment period following the October 2008 

FR Notice ......................................................................................................................................... 26

EPA Comment Code: 1500 EPA's handling of comments on the October 2008 FR 

Notice ................................................................................................................................................ 45

EPA Comment Code: 1600 Length of the comment period following August 2009 FR 

Notice ................................................................................................................................................ 47

EPA Comment Code: 2000 Perchlorate Health Effects ..................................................................... 51

EPA Comment Code: 2100 NAS (NRC) review of perchlorate health effects and 

reference dose .................................................................................................................................. 62

EPA Comment Code: 2110 Regulatory determination based upon the already-established 

RfD ................................................................................................................................................. 103

EPA Comment Code: 2150 EPA's decision not to seek further input from the NRC on 

issues related to perchlorate ........................................................................................................ 109

EPA Comment Code: 2200 Use of NHANES biomonitoring data for health effects 

evaluation ....................................................................................................................................... 119

EPA Comment Code: 2300 Use of PBPK models from Clewell et al (2007) and Merrill 

et al (2005) to evaluate health effects ......................................................................................... 178

EPA Comment Code: 2400 Use of EPA’s PBPK model to evaluate health effects ................... 182

EPA Comment Code: 2410 Use of PBPK model to select life-stage-specific HRLs .................. 213

EPA Comment Code: 2420 Suggestions for alternative ways to use the PBPK model to 

inform the regulatory determination .......................................................................................... 217
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EPA Comment Code: 2500 Other health effects studies, models, and data for EPA to 

consider (besides NAS/NRC report, NHANES biomonitoring data, and PBPK 

models already evaluated) ............................................................................................................ 221

EPA Comment Code: 2600 Comments on expanding scope of risk assessment to 

include other goitrogens and/or dietary iodide deficiency ..................................................... 275

EPA Comment Code: 3000 Perchlorate Occurrence in Drinking Water...................................... 305

EPA Comment Code: 3100 UCMR 1 occurrence analysis .............................................................. 309

EPA Comment Code: 3120 UCMR 1 statistical methodology and nationally 

representative sample of small systems ..................................................................................... 325

EPA Comment Code: 3140 UCMR 1 entry-point-level estimation of perchlorate 

exposure ......................................................................................................................................... 327

EPA Comment Code: 3150 Potential use of a Bayesian model to estimate number of 

PWSs and population served at a range of thresholds ............................................................ 330

EPA Comment Code: 3160 Use of Census data to estimate populations that are in the 

sensitive life stage ......................................................................................................................... 338

EPA Comment Code: 3170 Accounting for variation of perchlorate levels in public 

water systems over time ............................................................................................................... 342

EPA Comment Code: 3200 Supplemental drinking water occurrence data from 

California and Massachusetts ...................................................................................................... 347

EPA Comment Code: 3300 Other drinking water occurrence studies, models, and data 

for EPA to consider (besides UCMR 1 and California and Massachusetts data 

already evaluated) .......................................................................................................................... 350

EPA Comment Code: 4000 Evaluation of Perchlorate Exposure from Sources Other 

than Drinking Water .................................................................................................................... 367

EPA Comment Code: 4110 Dietary studies – FDA’s 2005-2006 total dietary study (TDS) ...... 371

EPA Comment Code: 4130 Dietary studies -- other studies, models, and data (besides 

FDA’s 2005-2006 TDS, and 2003-2005 exploratory data) ..................................................... 375

EPA Comment Code: 4210 Biomonitoring -- urinary data from the 2001-2002 

NHANES study, and EPA/CDC’s NHANES-UCMR analysis ........................................... 382

EPA Comment Code: 4220 Biomonitoring -- breast milk studies discussed in the notice ........ 390

EPA Comment Code: 4230 Biomonitoring -- other biomonitoring studies, models, and 

data for EPA to consider (other than NHANES and breast milk studies discussed 

in the notice) .................................................................................................................................. 395

EPA Comment Code: 4300 Other perchlorate exposure studies, models, and data for 

EPA to consider (other than drinking water, diet, and biomonitoring) ............................... 397

EPA Comment Code: 5000 SDWA Criteria ...................................................................................... 399

EPA Comment Code: 5100 SDWA Criterion #1 – EPA’s determination that perchlorate 

may have adverse effects on the health of persons ................................................................. 403

EPA Comment Code: 5200 SDWA Criterion #2 – EPA’s determination that perchlorate 

occurs infrequently at levels of health concern in public water systems .............................. 406

EPA Comment Code: 5210 Derivation of the RSC ......................................................................... 412

EPA Comment Code: 5220 Derivation of the HRL ........................................................................ 419
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EPA Comment Code: 5225 Use of alternative HRLs specific to sensitive life stages, as 

described in Table 2 of the August 2009 FR notice. ............................................................... 448

EPA Comment Code: 5230 Calculation of frequency of exposure above the HRL among 

pregnant women ........................................................................................................................... 483

EPA Comment Code: 5240 Consideration of other sensitive subpopulations (e.g., 

infants, children, and persons with iodine deficiency or thyroid disorders) when 

establishing the HRL .................................................................................................................... 485

EPA Comment Code: 5300 SDWA Criterion #3 – EPA’s determination that regulating 

perchlorate with a NPDWR would not represent a meaningful opportunity to 

reduce health risks for persons served by public water systems ............................................ 504

EPA Comment Code: 6000 EPA Actions ......................................................................................... 524

EPA Comment Code: 6100 EPA’s preliminary determination not to regulate perchlorate ....... 525

EPA Comment Code: 6110 Comments urging EPA not to regulate perchlorate ....................... 527

EPA Comment Code: 6120 Comments urging EPA to regulate perchlorate .............................. 564

EPA Comment Code: 6125 Comments critical of preliminary determination (in the 

October 2008 FR Notice) specific to Washington Post article ........................................... 1004

EPA Comment Code: 6130 Miscellaneous comments on the preliminary determination 

not to regulate (in the October 2008 FR Notice) .................................................................. 1006

EPA Comment Code: 6140 Additional new literature and information for EPA to 

consider when making a regulatory determination ................................................................ 1020

EPA Comment Code: 6200 Comments related to EPA’s health advisory ................................. 1037

EPA Comment Code: 6210 Need for EPA to provide additional support to States and 

water systems ............................................................................................................................... 1042

EPA Comment Code: 6300 EPA's intention to revise guidance on clean-up levels 

(preliminary remediation goals) ................................................................................................ 1046

EPA Comment Code: 6310 Clean up as a solution ........................................................................ 1049

EPA Comment Code: 6400 EPA's decision to subject updated PBPK model to peer 

review during comment period (in the October 2008 FR Notice) ..................................... 1051

EPA Comment Code: 6500 Comments on alternative risk reduction approaches .................... 1057

EPA Comment Code: 7000 Miscellaneous Comments ................................................................. 1063

EPA Comment Code: 7100 N/A May 2007 Comments ............................................................... 1086

APPENDIX 1 – COMPLETE LIST OF EPA COMMENT CODES ..................................................1097

List of Exhibits

Exhibit 1: Public Submissions by Category Type ......................................................................................... 3
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1. Introduction and Overview 

Background 

The U.S. Environmental Protection Agency (EPA or The Agency) is required by the Safe Drinking 

Water Act (SDWA), as amended in 1996, to publish a list of contaminants (Drinking Water 

Contaminant Candidate List, or CCL) that are known or anticipated to occur in public water 

systems, and which may require regulation under the SDWA. The CCL 2 was published in a Federal 

Register Notice (FR Notice) on February 24, 2005 (70 FR 9071). The Agency is also required to 

make Regulatory Determinations on at least five of the CCL contaminants following publication. 

EPA published preliminary regulatory determinations for 11 of 51 total contaminants from CCL 2 

on May 1, 2007 (72 FR 24016). In the 2007 notice, perchlorate was not part of the list of 11 

contaminants, however, the Agency asked for new information and data related to perchlorate. 

Subsequently, EPA made a final regulatory determination not to regulate the 11 of the contaminants 

identified in the May 1, 2007 Federal Register notice. Responses to public comment regarding these 11 

contaminants were answered as part of the final regulatory determination process and posted to 

www.regulations.gov (refer to document ID EPA-HQ-OW-2007-0068-0178). 

The Agency deferred responding to comments on perchlorate, and issued a separate preliminary 

determination not to regulate perchlorate on October 17, 2008 (73 FR 66895), followed by an 

additional public comment period. In a third Federal Register notice, issued on August 19, 2009 (74 

FR 41883), EPA requested new information and data via public comment. The purpose of issuing 

the notice was to obtain comments on additional approaches to analyzing data related to EPA’s 

regulatory determination. EPA wanted to ensure consideration of all the potential options for 

evaluating whether there is a meaningful opportunity for human health risk reduction of perchlorate 

through a national primary drinking water rule. 

This final comment response document presents the comments and responses for all three 

comment periods. Approximately 39,000 public submissions (in the form of letters, apparent mass 

mailing campaigns, e-mails, and/or postings to www.regulations.gov) were received by EPA. All 

original public submissions can be found in their respective docket locations; at 

www.regulations.gov, under Docket ID EPA–HQ–OW–2007–0068 for the May 2007 notice; EPA–

HQ–OW–2008–0692 for the October 2008 notice; and EPA–HQ–OW–2009–0297 for the August 

2009 notice. 

EPA’s Categorization of Public Comments and Document Organization 

Within the 3 Federal Register notices related to perchlorate, EPA sought public comment on a number 

of topics, including: regulatory determination; the approach EPA used to make its determination; 

new data and information; and several other issues specific to the individual FR notices. To address 

and respond to the public comments that were received, EPA developed a list of numerically 

ordered topics (referred to as “EPA Comment Codes”) that were likely to be addressed by 

commenters (typically based on the outlines of the draft FR notices). Not all of the EPA Comment 

Codes were addressed by commenters. The complete list of EPA Comment Codes is provided in 

Appendix 1, including notation for codes that did not receive comments. 

To organize and track public submissions, EPA assigned a document identification (ID) number . 

These “document IDs” were assigned to give each public submission a unique identifier, and to tie 

each submission to the docket for the Federal Register notice it was submitted under, or to identify it 
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as the representative letter from an apparent mass mailing campaign (see discussion below regarding 

mass mailing campaigns). 

Each public submission was read by EPA, and, where appropriate, was subdivided into “comment 

sections,” or distinct issue areas, based on topical breaks within the submission. EPA grouped these 

comment sections (hereinafter referred to as “comments”) and assigned a five digit EPA comment 

identification (ID) number or “comment ID.” Comments that were similar in topic were then 

grouped together into a corresponding EPA Comment Code. Each EPA Comment Code was 

assigned a four digit reference number. 

Apparent Mass Mailing Campaigns – Section 2 

EPA received more than 37,000 public submissions from 11 apparent mass mailing campaigns. EPA 

read each submission and determined if it was part of a campaign. Only one representative letter 

(the first letter that was received) from each campaign is included in this response to comment 

document. The representative letters from each campaign appear in their entirety in Section 2 of this 

report. Each individual letter is presented in the order in which it was originally written, separated 

into its individual comments (i.e., at topical breaking points), with each comment followed by the 

associated EPA response (see explanation on the next page regarding cross referencing of responses, 

and response to comment codes). Each comment from a campaign also appears in Section 3, under 

its assigned EPA Comment Code. 

Comments and Responses by Comment Code – Section 3 

Section 3 presents the public comments and EPA’s responses. These are organized first by EPA 

Comment Code, (i.e., the topical subsections within Section 3); then within each Comment Code, 

comments are organized numerically by EPA Comment ID. Readers can first find the comment 

code for topics they are interested in, and then find responses to specific Comment IDs for 

individual comments. The commenter name, organization, and document ID are also given for each 

comment. Any comment can be read as it appears within the commenter’s original letter, e-mail, or 

posting by searching on the associated Document ID on www.regulations.gov (see explanation of 

Document IDs in the introduction to this section, “EPA’s Categorization of Public Comments and 

Document Organization”). The Document ID can also be used to find additional information, such 

as tables or figures, which may be included within the context of comments or attachments in the 

commenter’s original submission. 

Cross Referencing of Responses 

In many cases, several commenters addressed the same or similar issues. For these comments, EPA 

has cross referenced responses to avoid redundancy and to ensure consistency. Responses are cross 

referenced by providing the pertinent EPA Comment ID, along with the EPA Comment Code 

where the EPA Comment ID is located. As noted above, Section 3 is organized first by EPA 

Comment Code (the subsections within the chapter), then numerically by EPA Comment ID. 

Response to Comment Code 

Many comments received by EPA addressed similar topics, and were thus grouped under the same 

EPA Comment Code. In several of these cases, the same response was appropriate for multiple 

comments, and EPA developed a “Response to Comment Code” which appears at the beginning of 

each EPA Comment Code section. Responses to individual comments may point the reader to the 

appropriate Response to Comment Code. 
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Who Submitted Comments 

Because EPA received approximately 39,000 public submissions it is not practical to list all 

commenters and the topics they commented on. However, in reviewing commenter submissions 

and profiles, EPA binned commenters into 12 categories to provide a broad characterization of 

interested stakeholders. Exhibit 1, below, lists commenter category, and the number of comments 

received within each category. 

Exhibit 1: Public Submissions by Category Type 

Category Type Number of Public 

Submissions 

Academia / Professional Societies (including: university departments, 

professors (even if writing on their own behalf)) 10 

Consultants 19 

Drinking Water Organizations 19 

Drinking Water Systems 7 

Environmental Groups 44 

Federal Government 4 

Individual Manufacturers/Companies 2 

Industry Groups 14 

Local Government 6 

States 31 

Worker & Public Health Groups 9 

Private Citizen and Anonymous Commenters Approximately 38,800 

1. Original documents can be found in the docket at http://www.regulations.gov, under Docket EPA–HQ–OW–2007–0068 for the 

May 2007 FR; EPA–HQ–OW–2008–0692 for the October 2008 FR; and EPA–HQ–OW–2009–0297 for the August 2009 FR. 

2. A complete list of the EPA Comment Codes and their descriptions can be found in Appendix 1. 
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2. Apparent Mass Mailing Campaigns 

Apparent Mass Mailing #1 - Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0081 

EPA Comment ID: 19687 

EPA Comment Code: 6120 

Comment: This is a Public Comment Regarding EPA’s refusal to regulate Perchlorate under the 

Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): Perchlorate is a chemical in rocket 

fuel that has been linked to thyroid problems in pregnant women, newborns and young children. 

Not regulating this harmful chemical in our drinking water is unacceptable. Perchlorate is found in 

drinking water in 35 states, and according to the EPA’s own data, 16 million Americans are at risk of 

being exposed to this dangerous chemical. 

Response: See response to comment code 6120. 

EPA Document ID: EPA-HQ-OW-2008-0692-0081 

EPA Comment ID: 19688 

EPA Comment Code: 5300 

Comment: Setting a standard for perchlorate will absolutely present ‘a meaningful opportunity for 

health risk reduction.’ I urge you to do so in accordance with the Safe Drinking Water Act and 

protect Americans’ health. 

Response: See response to comment code 5300. 

Apparent Mass Mailing #2 - Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0100 

EPA Comment ID: 19689 

EPA Comment Code: 6120 

Comment: The Environmental Protection Agency (EPA), supposedly protecting us against harmful 

chemicals in our air, water and food, has formally refused to set a drinking- water standard for 

perchlorate, a chemical in rocket fuel that has been linked to thyroid problems in pregnant women, 

newborns and young children. 

Response: See response to comment code 6120. 

EPA Document ID: EPA-HQ-OW-2008-0692-0100 

EPA Comment ID: 19690 
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EPA Comment Code: 5220 

Comment: The maximum safe level for perchlorate in drinking water is now 15 times higher than 

what the EPA declared safe in 2002. Under this new standard, more than 16 million Americans are 

exposed to unsafe levels of perchlorate in their drinking water, and independent analysis shows 

anywhere from 20 to 40 million Americans at risk. Perchlorate has been found in the drinking water 

in 35 states in the U.S. 

Response: See response to comment 19873 under comment code 5220. 

EPA Document ID: EPA-HQ-OW-2008-0692-0100 

EPA Comment ID: 19691 

EPA Comment Code: 6120

Comment: The Senate Environment and Public Works Committee has endorsed legislation 

requiring the EPA to set a federal standard for perchlorate and to monitor levels of the chemical in 

tap water. Please regulate perchlorate in our drinking water: Your current decision is harmful to 

public health. 

Response: See response to comment code 6120. 

Apparent Mass Mailing #3 Group Unidentified 

EPA Document ID: EPA-HQ-OW-2008-0692-0561 

EPA Comment ID: 19964 

EPA Comment Code: 1300

Comment: Docket Identification (ID) Number: EPA-HQ-OW-2008-0692 Preliminary Regulatory 

Determination on Perchlorate Re: Request for extension of comment period I am writing to express 

my concern regarding the EPA's failure to regulate perchlorate, as well as the proposed reference 

level, which fails to protect - and will adversely affect -- the health and development of hundreds of 

thousands, perhaps millions of American children. EPA has spent a number of years researching 

perchlorate and developing its conclusions - which are considered highly controversial and complex. 

They require, therefore, the time for measured and throughful public response. We cannot afford to 

have this decision rushed through, in the last days of the current administration, and leaving those 

communities that face the greatest risk without enough time to comment. It takes time for public 

and community groups to evaluate EPA's findings, review the ever-changing scientific literature, and 

prepare comments. I therefore request that the EPA extend the 30-day comment period on its 

October 10, 2008 Preliminary Regulatory Determination on Perchlorate to 90 days. 

Response: See the response to comment code 1300. EPA plans to initiate the process of proposing 

a national primary drinking water regulation for perchlorate (see response to comment code 6120). 
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Apparent Mass Mailing #4 - Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-0687 

EPA Comment ID: 20016 

EPA Comment Code: 6120 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 Dear Administrator Johnson and EPA 

staff, I urge you to set a drinking water standard for perchlorate that will protect pregnant women 

and babies nationwide. Perchlorate poses a risk for pregnant women, newborns and young children 

by interfering with thyroid hormone, which is critical for optimal development of the brain and 

nervous system. Perchlorate is found in drinking water in at least 26 states, and 20-40 million people 

could be exposed to this chemical. Several states have set drinking water standards or guidelines for 

this chemical, but these standards vary widely, so it is critical for the EPA to set a national standard 

that is based on the best available science and that will protect public health. The EPA's own staff 

scientists have determined that your decision not to regulate perchlorate places some infants and 

young children above safe levels of exposure. The EPA's current draft scientific analysis should 

undergo independent scientific peer review and should be used as the basis for the regulation. 

Response: 

The Agency believes that further review by the National Research Council would unnecessarily delay 

regulatory decision making for perchlorate. Therefore, EPA is not, at present, planning to request 

additional NRC review of issues related to perchlorate. Instead, EPA issued a notice in August of 

2009 seeking comments on a broad range of alternative approaches to the interpretation of the 

scientific data relevant to a regulatory determination for perchlorate in drinking water. 

EPA has determined to regulate perchlorate in drinking water. See response to comment code 6120. 

EPA Document ID: EPA-HQ-OW-2008-0692-0687 

EPA Comment ID: 20017 

EPA Comment Code: 5300

Comment: All Americans deserve healthy and clean drinking water. The EPA should not finalize 

this decision until the scientific review is complete and should make decisions that are consistent 

with the agency's own scientists. Contrary to your claims, protecting the health of young children is 

indeed a "meaningful opportunity for health risk reduction." 

Response: See response to comment code 5300. 

EPA Document ID: EPA-HQ-OW-2008-0692-0687 

EPA Comment ID: 20018 

EPA Comment Code: 6120

Comment: Again, I urge you to reverse your decision and to set a national drinking water standard 

for perchlorate. 
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Response: See response to comment code 6120. 

Apparent Mass Mailing #5 - Clean Water Fund/Clean Water Action 

EPA Document ID: EPA-HQ-OW-2008-0692-0689 

EPA Comment ID: 20019 

EPA Comment Code: 6120

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. * perchlorate contamination 

is a nationwide problem and has health impacts at lower levels than previously thought; * a national 

primary drinking water regulation would provide a meaningful opportunity to protect public health. 

Additional Facts * Perchlorate is a harmful chemical used in rocket fuel, flares, and explosives. * 

Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development and metabolism. * Developing fetuses, infants and children with thyroid impairment 

may suffer mental retardation, loss of hearing and speech or deficits in motor skills. * EPA agrees 

that perchlorate has been found in 395 sites in 37 states, including 153 public water systems serving 

over 20 million people. Some estimates are even higher. 

Response: See response to comment code 6120. 

Apparent Mass Mailing #6 - Earth Justice 

EPA Document ID: EPA-HQ-OW-2008-0692-0972 

EPA Comment ID: 20884 

EPA Comment Code: 6120

Comment: Administrator Stephen L. Johnson 1101A EPA Headquarters 1200 Pennsylvania 

Avenue, NW, Ariel Rios Building Washington, DC 20460 Subject: Protect Our Drinking Water 

From Perchlorate Contamination Dear Administrator Johnson, I am writing to urge you reverse 

EPA's preliminary regulatory determination and set a protective drinking water standard for 

perchlorate as required by the Safe Drinking Water Act. Perchlorate contamination in our food and 

water supplies is too widespread, and its toxic effects too well known, for continued inaction on this 

problem. 

Response: See response to comment code 6120. 

EPA Document ID: EPA-HQ-OW-2008-0692-0972 

EPA Comment ID: 20885 

EPA Comment Code: 5240

Comment: Many experts disagree with your assessment that drinking water with 15 parts per billion 

of perchlorate is safe and acceptable. Scientists from the California Environmental Protection 
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Agency and the Massachusetts Department of Environmental Protection have set stricter standards 

to will ensure that the most vulnerable populations -- pregnant women, infants, and small children -- 

are protected from the adverse impacts of perchlorate. 

Response: See response to comment code 5220. 

EPA Document ID: EPA-HQ-OW-2008-0692-0972 

EPA Comment ID: 20886 

EPA Comment Code: 4000

Comment: EPA's analysis fails to consider that the combination of food and drinking water 

exposure to perchlorate in the U.S. population exceeds the reference dose set by EPA. Nor does it 

incorporate the more protective methodology behind the recent state regulatory actions. These flaws 

must be remedied for the sake of the millions of U.S. families exposed to dangerous levels of 

perchlorate contamination. 

Response: EPA considers the combination of food and drinking water through the relative source 

contribution (RSC). The RSC is the percentage of the reference dose remaining for drinking water 

after other sources of exposure to perchlorate have been considered (e.g., food). See the August 

2009 Federal Register notice (41887) for a detailed discussion of RSC derivation. 

Regarding the comment about incorporating methodologies behind recent state regulatory actions, 

States use different methodologies or assumptions to derive their own standard based on their 

unique exposure scenarios. EPA has used the best available peer reviewed science in making this 

regulatory determination. 

Apparent Mass Mailing #7 – Group Unidentified 

EPA Document ID: EPA-HQ-OW-2008-0692-1518 

EPA Comment ID: 20705 

EPA Comment Code: 6120

Comment: I understand the dangers of perchlorate and ask you to keep the testing requirement 

intact for our public drinking water supplies. Removal of the testing requirement would eliminate 

detection of perchlorate in the case of accidental or intentional contamination of drinking water 

supplies, such as the Tewksbury Massachusetts contamination in 2004. 

Response: See response to comment code 6120. 

Apparent Mass Mailing #8 - Food and Water Watch 

EPA Document ID: EPA-HQ-OW-2008-0692-1805 

EPA Comment ID: 20883 
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EPA Comment Code: 6120

Comment: Dear Administrator Johnson, I am writing to urge you to reconsider EPA's preliminary 

determination not to regulate perchlorate in drinking water. Perchlorate has been found in the 

drinking water supply of 35 states and the District of Columbia. Widespread human exposure to 

perchlorate was confirmed by the Center for Disease Control’s NHANES study, which found that 

100 percent of the 2,820 randomly selected study participants had detectable levels of perchlorate in 

their urine. The widespread exposure of the population to some level of perchlorate raises serious 

health concerns. Perchlorate can inhibit the thyroid gland’s iodine uptake, potentially leading to 

hypothyroidism. Severe hypothyroidism during pregnancy can lead to abnormal fetal cognitive 

development, and even mild hypothyroidism during pregnancy is associated with subtle cognitive 

defects in children. Thus, perchlorate could alter fetal brain development, having lifelong cognitive 

effects for those affected. EPA’s failure to regulate perchlorate in drinking water places consumers - 

especially children and pregnant women - at risk. In response to this misguided determination, 

EPA’s own Children’s Health Protection Advisory Committee has drafted a letter expressing its 

concern with EPA’s decision not to regulate perchlorate. Members of the committee claim that EPA 

rushed a decision on perchlorate without taking time to consider all the latest peer-reviewed studies. 

Given the vital importance of fetal central nervous development not only for long-term health and 

development of children, but also for the viability of fetuses, why would EPA rush to a decision? 

Unfortunately, the only conclusion we can draw is that EPA has issued this determination to avoid 

strapping the Department of Defense with costs to clean up near military bases, missile testing sites 

and chemical plants. While millions of consumers’ health is jeopardized, it seems the budget 

concerns of the Pentagon or White House are driving EPA’s decision. This determination is clearly 

another instance of a regulatory agency shirking its responsibility to protect the American public. 

Instead of fulfilling its obligations under the SDWA, EPA has once again folded to pressure. 

Response: See response to comment code 6120. 

Apparent Mass Mailing #9 - Group Unidentified 

EPA Document ID: EPA-HQ-OW-2008-0692-2366 

EPA Comment ID: 29116 

EPA Comment Code: 6120

Comment: Water Docket, EPA, Mailcode 2822T 1200 Pennsylvania Ave., NW Washington, DC 

20460 To Whom It May Concern: I urge you to reverse your decision and set a federal limit for 

perchlorate in drinking water. Perchlorate is a nationwide problem and has health impacts at lower 

levels than previously thought. Please protect public health, especially infants and children, by 

regulating perchlorate. 

Response: Please see the response to comment code 6120. 

Apparent Mass Mailing #10 - Group Unidentified 
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EPA Document ID: EPA–HQ–OW–2009–0297-0039 

EPA Comment ID: 28365 

EPA Comment Code: 6120

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. perchlorate contamination is a 

nationwide problem and has health impacts at lower levels than previously thought; protecting 

infants and children is critical. a national primary drinking water regulation would provide a 

meaningful opportunity to protect public health. 

Response: See response to comment code 6120. 

Apparent Mass Mailing #11 - Food and Water Watch 

EPA Document ID: EPA–HQ–OW–2009–0297-0526 

EPA Comment ID: 28614 

EPA Comment Code: 6120

Comment: Administrator Jackson USEPA Headquarters Ariel Rios Building 1200 Pennsylvania 

Avenue, N. W. Washington, DC 20460 September 18, 2009 Dear Administrator Jackson, I am 

writing, on behalf of Food and Water Watch, to urge you to make a national primary drinking water 

rule for perchlorate. Perchlorate has been found in the drinking water supply of 35 states and the 

District of Columbia. Widespread human exposure to perchlorate was confirmed by the Center for 

Disease Control's NHANES study, which found that 100 percent of the 2,820 randomly selected 

study participants had detectable levels of perchlorate in their urine. And according to your request 

for comment notice, dated August 5, 2009, the number of people served by water contaminated 

with high levels of perchlorate ranges between 53.4 and 16.8 million people. 

Response: See response to comment code 6120. 

EPA Document ID: EPA–HQ–OW–2009–0297-0526 

EPA Comment ID: 28615 

EPA Comment Code: 2150

Comment: Your decision to not request additional NRC review of issues relating to perchlorate is 

ill advised. Additional NRC research may better elucidate the health effect and exposure risk we 

presently face. Moreover, NRC research may provide better guidance in making a final regulatory 

determination, especially in determining the best health reference level (HRL). 

Response: Please see the response to comment ID 28822 under comment code 2150. 

EPA Document ID: EPA–HQ–OW–2009–0297-0526 

EPA Comment ID: 28616 

EPA Comment Code: 5225
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Comment: As suggested by previous commenter's, I believe that the Agency's proposed HRL, of 15 

micrograms/Liter, is too high. The alternative HRLs presented in Table 2 of your request for 

comment notice, dated August 5, 2009, do not use the most appropriate data. The data in Table 2 

uses mean ingestion rates from the CSFII. The CSFII is already several years out of date. 

Response: Regarding the Agency's proposed HRL of 15 ug/L being too high, see response to 

comment code 5220. Regarding use of CSFII data, EPA believes that it is the best peer reviewed 

science that is available. 

EPA Document ID: EPA–HQ–OW–2009–0297-0526 

EPA Comment ID: 28617 

EPA Comment Code: 3170

Comment: You also request comment on how the Agency should account for variation of 

perchlorate levels over time in public water systems. This is simple: the Agency should act with 

extreme precaution. 

Response: See response to comment code 6120. 

EPA Document ID: EPA–HQ–OW–2009–0297-0526 

EPA Comment ID: 28618 

EPA Comment Code: 6120

Comment: The widespread exposure of the population to some level of perchlorate raises serious 

health concerns. Perchlorate can inhibit the thyroid glands iodine uptake, potentially leading to 

hypothyroidism. Severe hypothyroidism during pregnancy can lead to abnormal fetal cognitive 

development, and even mild hypothyroidism during pregnancy is associated with subtle cognitive 

defects in children. Thus, perchlorate could alter fetal brain development, having lifelong cognitive 

effects for those affected. EPA's failure to regulate perchlorate in drinking water places consumers, 

especially children and pregnant women, at risk. We urge the EPA to consider the regulation of 

perchlorate as an opportunity to protect our waterways and make our drinking water safe for all. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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3. Comments and EPA Responses by Comment Code 

EPA Comment Code: 1000 General Comments 

Individual Comments 

Commenter Name: Julie L. Heckman 

Commenter Organization: American Pyrotechnics Association (APA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0522 

EPA Comment ID: 28489 

EPA Comment Code: 1000 

Comment: Please see the attached comments of the American Pyrotechnics Association. 

Attachment 

 September 18, 2009 

EPA Docket Center (Water Docket) U.S. Environmental Protection Agency EPA West Building 

1301 Constitution Ave., N.W., Room: 3334, Mail Code: 2822T Washington, DC 20004 

Re: Drinking Water: Perchlorate Supplemental Request for Comments, 74 Fed. Reg. 41883 (Aug. 19, 

2009); Docket ID No. EPA-HQ-OW-2007-0297; RIN 2040-AF08 

Dear Sir or Madam: 

These comments are submitted on behalf of the American Pyrotechnics Association ("APA"), in 

response to the above-referenced Notice and Supplemental Request for Comments ("Notice") 

appearing in the Federal Register on Wednesday, August 19, 2009. We appreciate the opportunity to 

provide the Agency with these comments. 

Interest of the APA 

The APA is the principal safety and trade association of the fireworks industry representing 

manufacturers, importers, distributors, retailers, suppliers, and professional public display firms. The 

APA has over 240 member companies. Along with their subsidiaries, APA member companies are 

responsible for 90 percent of the fireworks manufactured, imported, distributed and displayed in the 

U.S. 

The fireworks industry is predominately comprised of small family businesses that together, on one 

day each year, serve almost all of the nation and its citizens with the very special honor of 

celebrating this country's most patriotic of holidays, Independence Day, the Fourth of July. This is a 

responsibility entrusted to us by the founders themselves. 

Response: No response is necessary to the information provided by the commenter. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Commenter Name: Julie L. Heckman 

Commenter Organization: American Pyrotechnics Association (APA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0522 

EPA Comment ID: 28491 

EPA Comment Code: 1000 

Comment: Perchlorate has recently been used in fireworks because it is essential to the formula to 

cause the fireworks compositions to burn properly. The perchlorate formulas replaced chlorate 

formulas, which were less stable and highly friction sensitive, in order to provide a much safer 

product. The perchlorate formulas are designed so that the perchlorate is consumed during 

combustion. Efforts to replace perchlorate continue, but the technology for a safe, equally effective 

substitute is still developing. 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0649 

EPA Comment ID: 28494 

EPA Comment Code: 1000 

Comment: October 7, 2009 

U.S. Environmental Protection Agency Mailcode 2822T 1200 Pennsylvania Ave., NW. Washington, 

DC 20460 

Subject: Docket ID No. EPA-HQ-OW-0297 

Reference: Drinking Water: Perchlorate Supplemental Request for Comments (Federal Register / 

Vol. 74, No. 159 / Wednesday, August 19, 2009 / Notices 

This letter is submitted to correct and clarify comments provided by the Nevada Division of 

Environmental Protection (NDEP) dated September 16, 2009 in response to the referenced 

"Supplemental Request for Comments" noticed by the U.S. Environmental Protection Agency 

(EPA) in the August 19, 2009 Federal Register; Docket ID No. EPA-HQ-OW-2009-0297. 

The modifications to our earlier submittal concern the description of analytical methods and 

detection limits associated with perchlorate data collected and reported by the Metropolitan Water 

District (MWD) of Southern California for the Whitsett Intake. The NDEP is providing these 

corrections even though these corrections do not change the NDEP's analyses or recommendations 

provided in our original submittal. 

The necessary corrections relate to several dates and a reporting limit that were provided on page 16 

of 22 within the referenced submittal. Specifically, following submittal of initial comments by the 

NDEP, it came to our attention that: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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* A change from a reporting limit of 4 ug/L to 2 ug/L occurred early than was referenced; * A 

change from EPA Method 314 to EPA Method 331 occurred earlier than was referenced; * A 

change from EPA Method 331 to EPA Method 332 occurred earlier than was referenced; and * The 

MWD is being provided a 0.1 ug/L reporting limit for EPA Method 331 and EPA Method 332. 

A corrected page 16 of 22 to the September 16, 2009 NDEP submittal is attached to this letter to 

serve as an errata replacement page to our earlier submittal. Track change mode was used to 

provided clarity and transparency related to this revision. Please use the provided errata to update 

your records. Additionally, please contact the undersigned should you wish to discuss these data 

further. 

The NDEP appreciates this opportunity to provide the EPA with helpful information to enable the 

EPA to make a thoughtful and credible decision regarding whether there is a meaningful 

opportunity for health risk reduction to persons served by public water systems through 

promulgating a national drinking water rule for perchlorate. 

Sincerely, Tom Porta, Deputy Administrator Nevada Division of Environmental Protection 

Tp/tjc cc Jennifer Carr, P.E., CEM, Chief, Bureau of Safe Drinking Water, Nevada Division of 

Environmental Protection, 901 S. Stewart Street, Suite 4001, Carson City, NV 89701-5249 Darrel 

Osterhoudt, Regulatory Affairs Manager, Association of State Drinking Water Administrators, 1401 

Wilson Blvd., Suite 1225, Arlington, VA 22209 Kay Brothers, Deputy General Manager, SNWA 

Engineering/Ops, Southern Nevada Water Authority, 100 City Parkway, Suite 700, Las Vegas, NV 

89106 Dr. Mic Stewart, Manager, Water Quality Section, Metropolitan Water District of Southern 

California, 700 North Alameda Street, Los Angeles, CA 90012 Marie Pearthree, Assistant General 

Manager, Central Arizona Water Conservation District, PO Box 43020, Phoenix, AZ 85080-3020 

Brenda Pohlmann, Environmental Programs Manager, City of Henderson, PO Box 95050, 

Henderson, NV 89009 Susan Crowley, Tronox, LLC, PO Box 55, Henderson, NV 89009 Jeff 

Gibson, AMPAC, 3883Howard Hughes Parkway, Suite 70, Las Vegas, Nevada 89109 

Attachment [See PDF docket ID EPA-HQ-OW-2009-0297-0649; this corrects docket ID EPAHQ-OW-2009-0297-0638] 

Response: No response is necessary to the information provided by the commenter and the errata 

sheet. 

Commenter Name: Anthony Russo 

Commenter Organization: Chemistry Council of New Jersey (CCNJ) 

EPA Document ID: EPA-HQ-OW-2009-0297-0673 

EPA Comment ID: 28691 

EPA Comment Code: 1000 

Comment: An arbitrarily low standard for perchlorate could result in misdirected regulatory action 

against any and all low level contaminants in our water supply and the negative public health impacts 

that will follow from that. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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CCNJ appreciates this opportunity to comment. We believe that the scientific evaluation of 

perchlorate has become quite complicated over the past few years and that there is still the need for 

study and debate. We hope that CPA will carefully consider our comments. 

Sincerely, Anthony Russo Director of Regulatory Affairs CCNJ 

Response: Please see the response to comment code 6120. 

Commenter Name: Janice Dunn 

Commenter Organization: California Space Authority (CSA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0671 

EPA Comment ID: 28692 

EPA Comment Code: 1000 

Comment: October 6, 2009 

Ms. Lisa P, Jackson Administrator U.S. Environmental Protection Agency 1200 Pennsylvania 

Avenue, NW Washington, DC 20460 

RE: EPA-HQ-OW-2009-0297, "Drinking Water: Perchlorate - Supplemental Request for 

Comments," 74 FR 159:41883, 19 August 2009 

Dear Ms. Jackson: 

The California Space Authority (CSA) is a nonprofit corporation representing the commercial, civil, 

and national defense/homeland security interests of California's diverse space enterprise community. 

Therefore, we feel compelled to share our concern regarding the Environmental Protection Agency 

(EPA) request for public comments regarding data related to EPA's perchlorate regulatory 

determination (the Notice; U.S. EPA, 2009b). 

Earlier this year, President Obama issued a broad directive that would guarantee scientific integrity 

in all federal policy making. We strongly support this policy standard. CSA believes that additional 

approaches proposed by EPA which support a possible regulatory determination are consistent with 

this directive. 

There is a substantial body of scientific evidence related to the health risks associated with 

perchlorate. Five decades of scientific investigation, including a landmark National Academy of 

Sciences (NAS) review, result in a clear and consistent conclusion: low levels of perchlorate are not 

dangerous to public health. 

CSA respectfully requests that the EPA support sound public policy which protects human health 

and is based on solid science standards. 

Sincerely, Janice Dunn Deputy Director 

Response: Please see the response to comment code 6120. 

Commenter Name: Robert E. Brackett 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Commenter Organization: Grocery Manufacturers Association (GMA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0413 

EPA Comment ID: 28705 

EPA Comment Code: 1000 

Comment: GMA appreciates the opportunity to provide comments on the public notice regarding 

alternative approaches to the interpretation of the scientific data relevant to a regulatory 

determination for perchlorate in drinking water. 

Attachment 

 September 18, 2009 

Water Docket Environmental Protection Agency Mailcode 2822T 1200 Pennsylvania Avenue, NW 

Washington, DC 20460 

RE: Docket No. EPA-HQ-OW-2009-0297, "Drinking Water: Perchlorate - Supplemental Request 

for Comments," 74 FR 159:41883, 19 August 2009 

Dear Sir/Madam: 

The Grocery Manufacturers Association (GMA) represents the world's leading food, beverage and 

consumer products companies. The Association promotes sound public policy, champions 

initiatives that increase productivity and growth and helps to protect the safety and security of the 

food supply through scientific excellence. The GMA board of directors is comprised of chief 

executive officers from the Association's member companies. The $2.1 trillion food, beverage and 

consumer packaged goods industry employs 14 million workers, and contributes over $1 trillion in 

added value to the nation's economy. 

GMA appreciates this opportunity to provide comments on the above referenced public notice 

regarding alternative approaches to the interpretation of the scientific data relevant to a regulatory 

determination for perchlorate in drinking water. 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28826 

EPA Comment Code: 1000 

Comment: AMWA's comments are presented in two parts. The first part focuses on several areas 

where AMWA requests clarification or makes recommendations including: EPA's alternative HRL 

analysis, review of this analysis and the PBPK model by the National Academies National Research 

Council, EPA's population estimates, the Inspector General (IG) report, the significance of the 

reference dose (RfD) being set at a no observed effect level (NOEL) rather than a no observed 

adverse effect level (NOAEL), and the science surrounding perchlorate. The second part of the 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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letter provides responses to three issues where EPA specifically requested comment in the Federal 

Register (FR) notice. 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 29080 

EPA Comment Code: 1000 

Comment: Is perchlorate known to occur or is there a substantial likelihood that perchlorate occurs 

at a frequency and at a level of public health concern in public water systems? 

Perchlorate is not known or likely to occur in public water systems with high enough frequency nor 

does it occur at levels of public health concern. The NHANES studies and breast milk 

biomonitoring studies, notwithstanding their limitations, reveal that the US population is not 

exposed to levels of perchlorate that could cause an adverse effect, even when all exposure sources - 

in food and water - are considered. 

In the NHANES results, Americans 6 years and older had a 50th percentile dose of perchlorate at 

the time of sampling equivalent to 2.2 ppb in drinking water. (Blount, 2006) This dose is less than 10 

percent of the conservative NOEL level that is the basis of EPA's RfD and 7,000 times lower than 

the NOAEL. Less than 0.004% of the population has the potential for exposure to perchlorate 

above the RfD. (Blount, 2006) By all standard regulatory benchmarks EPA uses to determine 

acceptable incremental potential population risk from drinking water exposure, total perchlorate 

exposure has not required regulation. If total exposure does not present a meaningful risk for 

regulatory purposes, it follows that the risk from exposure to perchlorate in drinking water only is 

even smaller. 

The sole effect of setting a drinking water standard would be to reduce this already insignificant 

fraction. Rarely does EPA have both toxicology and exposure measures of such high quality. This 

evidence shows that drinking water is not a significant source of perchlorate for the population. 

The nationally-representative Unregulated Contaminant Monitoring Rule 1 results show that 

perchlorate does not occur frequently or at levels of public health concern in public water systems. 

The process for collecting data on unregulated contaminants in large and small water systems has 

been well established and relied upon by EPA for past Contaminant Candidate List (CCL) regulatory 

determinations. The UCMR is the most complete source of information on contaminant occurrence 

in the nation's drinking water sources. The use of UCMR sampling data for regulatory 

determinations has been well established. 

Response: EPA has determined that perchlorate occurs or there is a substantial likelihood that 

perchlorate will occur with a frequency and at levels of health concern in public water systems. 

Therefore, EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 18 of 1099

EPA disagrees with the interpretation of the NHANES studies and breast milk monitoring revealing 

that the US population is not exposed to levels of perchlorate that could cause an adverse effect. 

The NHANES studies did not measure exposure in infants and children under the age of 6. In light 

of the discussion presented in the final regulatory determination notice and the information available 

at this time, EPA believes that a NPDWR for perchlorate could reduce perchlorate exposures to 

levels below the potential alternative HRLs. 

EPA disagrees with the statement that the UCMR 1 results show that perchlorate does not occur 

frequently or at levels of public health concern in public water systems. EPA believes that the 

UCMR 1 is the best available data on the frequency and level of perchlorate occurrence in public 

water systems nationally. UCMR 1 indicated that 5.1 to 16.6 million people are served by PWSs, for 

which we have data, that have detected perchlorate at levels above the potential health levels. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 1100 SDWA requirements and the CCL and Regulatory 

Determinations process 

Individual Comments 

Commenter Name: James Taft

Commenter Organization: Association of State Drinking Water Administrators (ASDWA)

EPA Document ID: EPA-HQ-OW-2007-0068-0169

EPA Comment ID: 20285

EPA Comment Code: 1100 

Comment: States are also very interested in the contaminants for which a decision has not yet been 

proposed but where EPA shared information in the notice on the status of its analysis of these 

chemicals. Contaminants in this category include MTBE and perchlorate. ASDWA appreciates the 

fact that EPA chose to share extensive information on these contaminants in the notice, since some 

of these contaminants are "hot" topics in many states. Even if regulatory decisions are not yet made, 

states need to know the current status to help them deal with public water systems where these 

contaminants have been found. ASDWA encourages EPA to continue to provide information on 

the status of their regulatory deliberations especially for contaminants like MTBE and perchlorate 

where there has been significant public and legislative interest. ASDWA and individual states are 

ready to assist and provide input to EPA's decision making at any time. We offer the following 

specific observations about perchlorate, metolachlor, and MTBE . 

Response: See response to comment ID 20264 under comment code 7100. 

Commenter Name: James Taft

Commenter Organization: Association of State Drinking Water Administrators (ASDWA)

EPA Document ID: EPA-HQ-OW-2007-0068-0169

EPA Comment ID: 20287

EPA Comment Code: 1100 

Comment: National regulations covering a contaminant that may be a very localized problem need 

to be considered very carefully. They must be supported by scientific data. If further information is 

needed on the sources of human exposure, states urge the Agency to consider such additional 

documentation before a regulatory determination is made. If analysis of additional data does support 

regulation, states do not believe there is adequate justification for establishing a new national 

drinking water standard. Under such circumstances, its primary impact would be to add more water 

quality monitoring without necessarily enhancing public health protection. If an MCL is eventually 

developed based on somewhat localized occurrence patterns, we would encourage the Agency to 

consider requiring targeted monitoring, based on preliminary initial rounds of monitoring, rather 

than uniform monitoring across the board. 

Response: EPA intends to develop monitoring requirements for perchlorate as part of a proposed 

National Primary Drinking Water Regulation. 

Commenter Name: D. Daley
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 20 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1625

EPA Comment ID: 20564

EPA Comment Code: 1100 

Comment: Please include perchlorate on the EPA's Contaminant Candidate List. I am concerned 

with the potential health risks to all living things from exposure to perchlorate, especially in drinking 

water. By leaving this contaminant on the EPA's Contaminant Candidate List, it will be given 

attention needed to control it's use and disposal properly and safely to prevent significant future 

pollution problems to the environment. As a licensed professional engineer with the State of 

Connecticut, I urge you to reverse the EPA's decision to remove this dangerous contaminant from 

the CCL and place it back on the CCL as it should be there. Please help keep this dangerous 

chemical out of our drinking water. 

Response: EPA included perchlorate on the first, second, and third Contaminant Candidate Lists 

that were published in the Federal Register on March 2, 1998 (63 FR 10273), February 24, 2005 (70 

FR 9071), and October 8, 2009 (74 FR 51850), respectively. EPA has decided to regulate perchlorate 

in drinking water. See response to comment code 6120. 

Commenter Name: Ron Curry

Commenter Organization: New Mexico Environment Department

EPA Document ID: EPA-HQ-OW-2008-0692-1796

EPA Comment ID: 20940

EPA Comment Code: 1100 

Comment: Furthermore, section 1412(b)(3)(A) of the SDWA requires that the EPA Administrator, 

when making a decision based on science, shall use "the best available peer-reviewed science and 

supporting studies conducted in accordance with sound and objective scientific practices."[FN27: 42 

U.S.C. [section] 300g-1(b)(3)(A) (Westlaw 2008).] However, according to EPA's Science Advisory 

Board (SAB), EPA's preliminary determination not to regulate perchlorate "relies on the use of a 

dosimetric model which is now undergoing letter peer review."[FN28: Letter from Dr. Deborah L. 

Swackhammer, Chair, EPA Science Advisory Board, and Dr. Joan Rose, Chair, EPA Science 

Advisory Board, Drinking Water Committee, to EPA Administrator Stephen L. Johnson, at 1 (Nov. 

5,2008).] Yet EPA plans to make a final determination whether to regulate perchlorate by December 

2008.[FN29: 73 Fed. Reg. at 60281.] Consequently, the SAB has expressed concern that the 

soundness of the dosimetric model "will not be publicly vetted."[FN30: Letter from Dr. 

Swackhammer & Dr. Rose, at 1.] The SAB stresses the importance of such peer review: "The quality 

of the scientific foundation for EPA's decisions depends on peer review, which brings a variety of 

scientific perspectives to bear on critical components of EPA's decisions. Where science 

assessments have been conducted with the benefit of external scrutiny, the end products have been 

better able to support the policy making process."[FN31: Id. at 2.7] It is critical, therefore, that EPA 

make the determination whether to regulate perchlorate with the benefit of fully peer-reviewed, and 

publicly- scrutinized scientific analysis. Failure of EPA to do so would be arbitrary and capricious 

and not in accordance with the requirements of the SDWA. 

Thank you for your consideration of these comments. 

Ron Curry Cabinet Secretary 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 21 of 1099

cc:Governor Bill Richardson Sarah Cottrell, Office of the Governor Attorney General Gary King 

Stephen R. Farris, Office of the Attorney General 

Response: Administrator Stephen Johnson replied to the SAB on January 9, 2009. The letter is 

available in EPA’s docket ID No. EPA-HQ-OW-2009-0297 for this notice. EPA agrees with the 

commenter that it is critical that EPA make the determination whether to regulate perchlorate with 

the benefit of fully peer-reviewed scientific analysis, which is available to the public. This comment 

was received prior to EPA's peer-review process for the PBPK (dosimetric) model, which has now 

been completed. EPA has made this determination based on a consideration of the best available 

peer reviewed science and data collected in accordance with accepted methods related to perchlorate 

occurrence in drinking water, the presence of perchlorate in foods, and the potential health effects 

of exposure to perchlorate. 

Commenter Name: Jennifer Sass, PhD.

Commenter Organization: Natural Resources Defense Council

EPA Document ID: EPA-HQ-OW-2008-0692-1988

EPA Comment ID: 20983

EPA Comment Code: 1100 

Comment: BACKGROUND 

In 1974, Congress enacted the federal Safe Drinking Water Act (SDWA) to protect the public health 

from contaminated drinking water supplies by regulating public drinking water systems. The SDWA 

was amended in 1986 and 1994, and requires EPA, inter alia, to publish national primary drinking 

water regulations, which must include both non-enforceable, health-based Maximum Contaminant 

Level Goals (MCLGs) and enforceable Maximum Contaminant Levels (MCLs).[FN7: 42 U.S.C. 

§300g-1(a)(1).] The MCLG must be set "at the level at which no known or anticipated adverse 

effects on the health of persons occur and which allows for an adequate margin of safety."[FN8: 42 

U.S.C. §300g-1(b)(4)(A).] In contrast, the MCL, the maximum level of a regulated contaminant that 

any particular covered public water system may deliver to any user, must be set "as close to the 

maximum contaminant level goal as is feasible."[FN9: 42 U.S.C. §300g-1(b)(4) (B).] SDWA requires 

EPA to set a national primary drinking water standard when it determines for a contaminant that: 

(i) the contaminant may have an adverse effect on the health of persons; (ii) the contaminant is 

known to occur or there is a substantial likelihood that the contaminant will occur in public water 

systems with a frequency and at levels of public health concern; and (iii) in the sole judgment of the 

Administrator, regulation of such contaminant presents a meaningful opportunity for health risk 

reduction for persons served by public water systems.[FN10: 42 U.S.C. §300g-1(b) (1)(A).] 

 SDWA also requires EPA to establish a "contaminant candidate list" (CCL) identifying a list of 

contaminants, not yet regulated by the Agency, which are known or anticipated to occur in drinking 

water and which may require regulation.[FN11: 42 U.S.C. §300g-1(b)(1)(B).] Every five years, EPA 

must determine whether or not to regulate five of the contaminants that appear on the CCL.[FN12: 

Id.] In March, 1998, EPA's first CCL included perchlorate, but the Agency did not choose to make 

any determination about whether to regulate the contaminant. In February, 2005, EPA announced 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 22 of 1099

its second CCL, CCL2, on which perchlorate appeared again. As a result of its status as a candidate 

contaminant, EPA subsequently announced this preliminary determination on perchlorate. 

Response: No response necessary to the information provided by the commenter. 

Commenter Name: Gregg Grunenfelder

Commenter Organization: National Drinking Water Advisory Council (NDWAC)

EPA Document ID: EPA-HQ-OW-2008-0692-2010

EPA Comment ID: 21008

EPA Comment Code: 1100 

Comment: November 26, 2008 

Mr. Stephen L. Johnson Administrator U.S. Environmental Protection Agency 1200 Pennsylvania 

Avenue, N.W. Washington D.C. 20460 

Dear Administrator Johnson: 

In follow-up to EPA’s October 10, 2008 preliminary regulatory determination for perchlorate in 

drinking water, the National Drinking Water Advisory Council (NDWAC) would like to again 

convey to EPA the necessity for more thorough health effects research to support Safe Drinking 

Water Act (SDWA) related regulations. While NDWAC members do not have a consensus position 

to relay on the perchlorate decision itself, the members fully support the need for a strong, 

scientifically valid basis upon which to make such decisions. 

On June 24, 2008, the NDWAC expressed to you our recommendation for a holistic drinking water 

research plan that includes the needed health effects research for Contaminant Candidate List (CCL) 

contaminants. The NDWAC strongly supports the CCL process and recommends that EPA 

consider a refocus of research priorities in order to ensure sound health effects data are available in a 

timely fashion to better inform future CCL decision-making processes. The availability of this type 

of information will become increasingly important as issues such as pharmaceuticals and personal 

care products in drinking water continue to be of concern to the public. 

Under the provisions of the SDWA the nation looks to EPA to set drinking water standards which 

are protective of the public’s health. When adequate health effects research information is lacking, 

important regulatory determinations can be controversial and potentially misguided. Lacking EPA 

leadership on standard setting, states can be pressed into making independent regulatory 

determinations. In the case of perchlorate, at least two different drinking water standards have 

already been set by California and Massachusetts. In addition, Congress may also be compelled to 

by-pass the CCL process when inadequate health effects data results in controversial regulatory 

determinations. 

Thank you for your consideration of this key recommendation on research needs. If you have any 

questions, please contact Veronica Blette, Designated Federal Officer for the NDWAC, at (202) 

564-4094. 

Sincerely, Gregg Grunenfelder Chair National Drinking Water Advisory Council 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 23 of 1099

cc: Benjamin H. Grumbles, Assistant Administrator for Water George Gray, Assistant 

Administrator for Research and Development Cynthia C. Dougherty, Director,Office of Ground 

Water and Drinking Water Ephraim King, Director, Office of Science and Technology Kevin 

Teichman, Deputy Assistant Administrator for Research and Development EPA Docket ID No. 

EPA-HQ-OW-2008-0692 

Response: EPA agrees that thorough health effects research can improve regulatory decisionmaking. We will continue to work with the NDWAC and other advisory groups to identify research 

needs for future decisions. 

Commenter Name: Michael Girard

Commenter Organization: Perchlorate Study Group

EPA Document ID: EPA-HQ-OW-2008-0692-1855

EPA Comment ID: 21103

EPA Comment Code: 1100 

Comment: Finally, should a final determination be made not to establish a NPDWR for 

perchlorate, EPA should also make clear that its final determination also removes perchlorate from 

the CCL3 list. Based on EPA's careful consideration of the scientific evidence, it has fully evaluated 

perchlorate and met its requirements under the law. Continued consideration of perchlorate would 

siphon resources away from the long list of other substances and microbes on the CCL3. 

X. References 

American Water Works Association, 2008). National Cost Implications of a Potential Perchlorate 

Regulation, Jul. 2008, at 31). 

Amitai Y, Winston G, Sack J, Wasser J, Lewis M, Blount BC, Valentin-Blasini L, Fisher N, Israeli A, 

Leventhal A. 2007. Gestational exposure to high perchlorate concentrations in drinking waer and 

neonatal thyroxine levels. Thyroid 17:843-850. 

Blount BC, Valentin-Blasini L, Osterloh JD, Mauldin JP, Pirkle JL. 2007. Perchlorate exposure of 

the US population, 2001-2002. J Expo Sci Environ Epidemiol. 17(4):400-7. 

Braverman LE, Pearce EN, He X, Pino S, Seeley M, Beck B, Magnani B, Blount BC, Firek A. 2006. 

Effects of six months of daily low-dose perchlorate exposure on thyroid function in healthy 

volunteers. J Clin Endocrinol Metab. 91(7):2721-4. Epub 2006 Apr 24. 

Clewell RA, Merrill EA, Gearhart JM, Robinson PJ, Sterner TR, Mattie DR, Clewell HJ 3rd. 2007. 

Perchlorate and radioiodide kinetics across life stages in the human: using PBPK models to predict 

dosimetry and thyroid inhibition and sensitive subpopulations based on developmental stage. J 

Toxicol Environ Health A 70:408-28. 

Greer MA, Goodman G, Pleus RC, Greer SE. 2002. Health effects assessment for environmental 

perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake in 

humans. Environ Health Perspect. 110(9):927-37. Erratum in: Environ Health Perspect. 2005 

Nov;113(11):A732. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 24 of 1099

Merrill EA, Clewell RA, Robinson PJ, Jarabek AM, Gearhart JM, Sterner TR, Fisher JW. 2005. 

PBPK Model for Radioactive Iodide and Perchlorate Kinetics and Perchlorate-Induced Inhibition of 

Iodide Uptake in Humans, Toxicological Sciences 83:25-43. 

Murray CW, Egan SK, Kim H, Beru N, Bolger PM. 2008. US Food and Drug Administration's 

Total Diet Study: Dietary intake of perchlorate and iodine. J Expo Sci Environ Epidemiol. 

National Research Council of the National Academies (NAS). 2005. Health Implications of 

Perchlorate Ingestion. Committee to Assess the Health Implications of Perchlorate Ingestion, Board 

on Environmental Studies and Toxicology, Division on Earth and Life Studies. Washington, D.C.: 

The National Academies Press. 

Tellez RT, Chacon PM, Abarca CR, Blount BC, Van Landingham CB, Crump KS, Gibbs JP. 2005. 

Longterm environmental exposure to perchlorate through drinking water and thyroid function 

during pregnancy and the neonatal period. Thyroid. 15(9):963-975. 

Response: EPA has decided to regulate perchlorate in drinking water. See response to comment 

code 6120. 

Commenter Name: Jennifer Sass

Commenter Organization: Natural Resources Defense Council (NRDC)

EPA Document ID: EPA-HQ-OW-2009-0297-0412

EPA Comment ID: 28793

EPA Comment Code: 1100 

Comment: REGULATORY BACKGROUND 

In 1974, Congress enacted the federal Safe Drinking Water Act (SDWA) to protect the public health 

from contaminated drinking water supplies by regulating public drinking water systems. The SDWA 

was amended in 1986 and 1994, and requires EPA, inter alia, to publish national primary drinking 

water regulations, which must include both non-enforceable, health-based Maximum Contaminant 

Level Goals (MCLGs) and enforceable Maximum Contaminant Levels (MCLs).[FN7: 42 U.S.C. 

[Sec] 300g-1(a)(1).] The MCLG must be set "at the level at which no known or anticipated adverse 

effects on the health of persons occur and which allows for an adequate margin of safety."[FN8: 42 

U.S.C. [Sec]300g-1(b)(4)(A).] In contrast, the MCL, the maximum level of a regulated contaminant 

that any particular covered public water system may deliver to any user, must be set "as close to the 

maximum contaminant level goal as is feasible."[FN9: 42 U.S.C. [Sec]300g-1(b)(4)(B).] SDWA 

requires EPA to set a national primary drinking water standard when it determines for a 

contaminant that: 

(i) the contaminant may have an adverse effect on the health of persons; (ii) the contaminant is 

known to occur or there is a substantial likelihood that the contaminant will occur in public water 

systems with a frequency and at levels of public health concern; and (iii) in the sole judgment of the 

Administrator, regulation of such contaminant presents a meaningful opportunity for health risk 

reduction for persons served by public water systems.[FN10: 42 U.S.C. [Sec] 300g-1(b)(1)(A).] 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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SDWA also requires EPA to establish a "contaminant candidate list" (CCL) identifying a list of 

contaminants, not yet regulated by the Agency, which are known or anticipated to occur in drinking 

water and which may require regulation.[FN11: 42 U.S.C. [Sec]300g-1(b)(1)(B).] Every five years, 

EPA must determine whether or not to regulate five of the contaminants that appear on the 

CCL.[FN12: Id.] 

In March, 1998, EPA's first CCL included perchlorate, but the Agency did not choose to make any 

determination about whether to regulate the contaminant. In February, 2005, EPA announced its 

second CCL, CCL2, on which perchlorate appeared again. As a result of its status as a candidate 

contaminant, EPA subsequently announced its preliminary determination not to regulate perchlorate 

in October, 2008. 

Response: No response necessary to the information provided by the commenter. 

Commenter Name: Diane VanDe Hei

Commenter Organization: Association of Metropolitan Water Agencies (AMWA)

EPA Document ID: EPA-HQ-OW-2009-0297-0494

EPA Comment ID: 28833

EPA Comment Code: 1100 

Comment: Consideration For Future Regulations 

The current regulatory framework in place in the US puts the burden on the government to show 

that a chemical is unsafe and must be regulated. This is a very slow process, which takes many years 

or even decades and often is done only after the presence of the specific chemical and its impacts 

have become well known. More importantly, the current process also lacks any incentive for 

chemical manufacturers to support source water protection, or to consider or disclose negative 

impacts of their products on human health and the natural environment and control the 

contaminants at generation points, which often would be much more economical than treating them 

at downstream water plants. 

The issue is becoming a critical one as new analytical methods can detect ever- increasing 

contaminants of emerging concern at parts per trillion and below, and as potential treatment to 

remove them could significantly add to the financial burden of water utilities, their energy needs and 

greenhouse gas emissions. 

These concerns can be resolved effectively and economically by a regulatory paradigm shift to put 

the lead responsibility where it belongs, i.e. on the generators of the contaminants. While it is not 

possible to address perchlorate in this way, in light of the new administration's reanalysis of the 

science of perchlorate, AMWA encourages this administration to also consider taking another look 

at how we can protect watersheds and drinking water quality by addressing preventable problems 

caused by the generators of chemicals and man-made sources of pollution. 

Response: Please see response to comment code 7000. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 26 of 1099

EPA Comment Code: 1300 Length of the comment period following the 

October 2008 FR Notice 

Response to Comment Code 1300: A number of commenters requested that EPA extend the 30 

day comment period for the Agency's preliminary regulatory determination for perchlorate (73 FR 

60262, October 10, 2008). In response to these comments, EPA extended the comment period until 

November 28, 2008, which provided commenters with 49 days to prepare comments. EPA received 

comment letters from over 37,000 individuals/ organizations on the October 2008 Federal Register 

Notice. 

Individual Comments 

Commenter Name: Jennifer Sass, PhD

Commenter Organization: Natural Resources Defense Council (NRDC)

EPA Document ID: EPA-HQ-OW-2008-0692-0322

EPA Comment ID: 19810

EPA Comment Code: 1300 

Comment: Document ID: EPA-HQ-OW-2008-0692-EPA-HQ-OW-2008-0692-0322 Last Name: 

Sass, PhD First Name: Jennifer Title: Organization: Natural Resources Defense Council (NRDC) 

City: State: Zip Code: Phone Number: Fax Number: Country Code: Email Address: Current 

Category Code: 302 

Comment: 

 October 17, 2008 

Docket identification (ID): EPA-HQ-OW-2008-00692 Preliminary Regulatory Determination on 

Perchlorate 

Re: Request for extension of comment period. 

The October 10, 2008 Federal; Register notice announcing EPA.s preliminary regulatory 

determination on perchlorate opened the public comment period for 30 days, with comments due 

by November 10, 2008. Given the importance of the science on perchlorate and the exposure data, 

the Natural Resources Defense Council (NRDC) respectfully requests a 60-day extension of the 

public comment period to January 10, 2008 (that is, 90 days from the October 10, 2008 notice). 

Response: See the response to comment code 1300. 

Commenter Name: Jennifer Sass, PhD

Commenter Organization: Natural Resources Defense Council (NRDC)

EPA Document ID: EPA-HQ-OW-2008-0692-0322

EPA Comment ID: 19813

EPA Comment Code: 1300 
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Comment: Council (NRDC) respectfully requests a 60-day extension of the public comment period 

to January 10, 2008 (that is, 90 days from the October 10, 2008 notice). 

EPA.s preliminary regulatory determination not to set a regulatory standard for perchlorate in 

drinking water could put 20 - 40 million people at risk for perchlorate toxicity, including infants, 

toddlers and pregnant women. A proposal with such far-reaching public health implications deserves 

careful and thorough comments with adequate time to review and respond to EPA.s analysis. 

Part of EPA.s preliminary determination relies on perchlorate monitoring data from the Unregulated 

Contaminant Monitoring Rule. The large amount of occurrence data collected over five years from 

almost 4000 public water systems will require additional time for NRDC and other stakeholders to 

review and assess, especially in light of the importance EPA placed on these data in the preliminary 

determinations. 

NRDC plans to submit public comments on this proposed determination, and a thoughtful and 

detailed technical response will require more than the 30 days that has been allotted by EPA. We 

respectfully request the comment period be extended by 60 days. 

Response: See response to comment code 1300. 

Commenter Name: Anila Jacob, M.D., M.P.H.

Commenter Organization: Environmental Working Group

EPA Document ID: EPA-HQ-OW-2008-0692-0466

EPA Comment ID: 19894

EPA Comment Code: 1300 

Comment: October 22, 2008 

Eric Burneson Office of Ground Water and Drinking Water Standards and Risk Management 

Division Environmental Protection Agency 1200 Pennsylvania Avenue, NW Washington, DC 

20460 

Re: Request for extension of comment period for Docket Identification (ID): EPA- HQ-OW- 2008-

0692- Preliminary Regulatory Determination on Perchlorate 

Dear Mr. Burneson: 

EPA announced it's preliminary regulatory determination on perchlorate in the Federal Register 

notice dated October 10, 2008 and opened a public comment period for 30 days, with comments 

due by November 10, 2008. Given the far- reaching public health implications ofEPA's 

determination, the Environmental Working Group (EWG) plans to thoroughly review EPA's 

document and submit comments. The document that EPA has produced is 80 pages long and highly 

technical and EWG respectfully requests that the comment period be extended by 60 days, so 

comments will be due 90 days from the October 10, 2008 notice. 

Response: See response to comment code 1300. 

Commenter Name: Anila Jacob, M.D., M.P.H.
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 28 of 1099

Commenter Organization: Environmental Working Group

EPA Document ID: EPA-HQ-OW-2008-0692-0466

EPA Comment ID: 19895

EPA Comment Code: 1300 

Comment: Perchlorate contamination of drinking water potentially affects 20 to 40 million US. 

residents and EPA's preliminary regulatory determination not to regulate perchlorate has serious 

health implication for these millions of people. A thorough and detailed response to EPA's 

determination will require EWG scientists to pore qver EPA's document line by line in order to 

effectively make our argument for stringent regulation of perchlorate in drinking water. As 

advocates for public health, EWG has a responsibility to submit the strongest document to EPA 

that we can and we feel that an extension of the public comment period by 60 days will allow us to 

do that. 

Thank you for your consideration. Best regards, Anila Jacob, M.D., M.P.H. Senior Scientist 

Environmental Working Group 

Response: See the response to comment code 1300. 

Commenter Name: Apparent Mass Mailing #3 Group Unidentified 

EPA Document ID: EPA-HQ-OW-2008-0692-0561

EPA Comment ID: 19964

EPA Comment Code: 1300 

Comment: Docket Identification (ID) Number: EPA-HQ-OW-2008-0692 Preliminary Regulatory 

Determination on Perchlorate Re: Request for extension of comment period 

I am writing to express my concern regarding the EPA's failure to regulate perchlorate, as well as the 

proposed reference level, which fails to protect - and will adversely affect -- the health and 

development of hundreds of thousands, perhaps millions of American children. 

EPA has spent a number of years researching perchlorate and developing its conclusions - which are 

considered highly controversial and complex. They require, therefore, the time for measured and 

throughful public response. 

We cannot afford to have this decision rushed through, in the last days of the current 

administration, and leaving those communities that face the greatest risk without enough time to 

comment. 

It takes time for public and community groups to evaluate EPA's findings, review the ever-changing 

scientific literature, and prepare comments. 

I therefore request that the EPA extend the 30-day comment period on its October 10, 2008 

Preliminary Regulatory Determination on Perchlorate to 90 days. 

Response: See the response to comment code 1300. EPA plans to initiate the process of proposing 

a national primary drinking water regulation for perchlorate (see response to comment code 6120). 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 29 of 1099

Commenter Name: Apparent Mass Mailing #3 Group Unidentified 

EPA Document ID: EPA-HQ-OW-2008-0692-0561

EPA Comment ID: 19964

EPA Comment Code: 1300 

Comment: Docket Identification (ID) Number: EPA-HQ-OW-2008-0692 Preliminary Regulatory 

Determination on Perchlorate Re: Request for extension of comment period 

I am writing to express my concern regarding the EPA's failure to regulate perchlorate, as well as the 

proposed reference level, which fails to protect - and will adversely affect -- the health and 

development of hundreds of thousands, perhaps millions of American children. 

EPA has spent a number of years researching perchlorate and developing its conclusions - which are 

considered highly controversial and complex. They require, therefore, the time for measured and 

throughful public response. 

We cannot afford to have this decision rushed through, in the last days of the current 

administration, and leaving those communities that face the greatest risk without enough time to 

comment. 

It takes time for public and community groups to evaluate EPA's findings, review the ever-changing 

scientific literature, and prepare comments. 

I therefore request that the EPA extend the 30-day comment period on its October 10, 2008 

Preliminary Regulatory Determination on Perchlorate to 90 days. 

Response: No reponse necessary, duplicate comment entry. 

Commenter Name: Anonymous

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0585

EPA Comment ID: 19968

EPA Comment Code: 1300 

Comment: time to comment should be extended. i want very much to hear what environmental 

working group comments. i trust them more than my own government agencies. and certainly more 

than profiteers. 

Response: See the response to comment code 1300. 

Commenter Name: S. Quezada 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0596 

EPA Comment ID: 19971 

EPA Comment Code: 1300 

Comment: Docket Identification (ID) Number: EPA-HQ-OW-2008-0692 Preliminary Regulatory 

Determination on Perchlorate Re: Request for extension of comment period 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 30 of 1099

Americans cannot afford to have a final determination on Perchlorate's safety rushed through in 

light of the high scientific controversy surrounding the matter. Therefore, I request an extension of 

public comments from 30 days to 90 days. This action by the EPA would be appropriate and 

prudent given the high scientific and academic controversy over the matter. Even the mere 

appearance of "rushing" is in appropriate and should be dispelled by providing Americans the 

opportunity to fully evaluate and meaningfully comment on the EPA's proposed perchlorate 

determination. 

The EPA has spent a number of years researching perchlorate and developing its conclusions. To 

now turn around and provide the American public 30 days for public comment on a complex matter 

is both unfair and questionable and certainly not aimed at obtaining "public comment." 

Sincerely, 

S. Quezada 

416 Ridgeview Ave 

Iowa City, Iowa 52246 

Response: See the response to comment code 1300. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0629 

EPA Comment ID: 19980 

EPA Comment Code: 1300 

Comment: Docket Identification (ID) Number: EPA-HQ-OW-2008-0692 Preliminary Regulatory 

Determination on Perchlorate Re: Request for extension of comment period 

To Whom It May Concern: 

It is clear that the issue of how/whether to regulate perchlorate is not a simply resolved one. Please 

extend the comment period on the October 10, 2008 Preliminary Regulatory Determination on 

Perchlorate to at least 90 days, so that as many entities with views and knowledge of the subject as 

possible may have a chance to be heard. The benefits of extending seem certain to outweigh any 

negatives that might be involved in doing so. 

Response: See the response to comment code 1300. 

Commenter Name: N Henry 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0637 

EPA Comment ID: 19984 

EPA Comment Code: 1300 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 31 of 1099

Comment: Please extend the comment period regarding perchlorate regulation. The quality of our 

water supply and health of our nation are serious matters, which require appropriate deliberation and 

evaluation. 

Thank you. 

Response: See the response to comment code 1300. 

Commenter Name: Lenny Siegel 

Commenter Organization: Center for Public Environmental Oversight 

EPA Document ID: EPA-HQ-OW-2008-0692-0642 

EPA Comment ID: 19985 

EPA Comment Code: 1300 

Comment: Attachments 

EPA-HQ-OW-2008-0692-0642.1 Comment attachment submitted by Lenny Siegel, Executive 

Director, Center for Public Environmental Oversight 

Eric Burneson Office of Ground Water and Drinking Water Standards and Risk Management U.S. 

Environmental Protection Agency 

REF: Docket ID# EPA-HQ-OW-2008-0068 

Dear Sir: 

I am concerned that EPA’s failure to regulate perchlorate, as well as its unprotective proposed 

health reference level, will adversely affect the health and development of hundreds of thousands, 

perhaps millions of American children. It has taken EPA years, with its extensive resources, to come 

to its conclusions. Its findings are complex and controversial. We cannot afford to have this decision 

rushed out the door, in the waning days of the current administration, without giving impacted 

communities sufficient time to comment. 

Organizations that advocate for public health and environmental protection have few people with 

the expertise, resources, and time to evaluate EPA’s findings, review continuously emerging 

scientific literature, and prepare comments. I therefore call upon EPA to extend the 30-day 

comment period on its October 10, 2008 Preliminary Regulatory Determination on Perchlorate to 

90 days. 

Sincerely, 

(submitted electronically) 

Lenny Siegel Executive Director 

 Cc: EPA Administrator Stephen Johnson 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 32 of 1099

Response: See the response to comment code 1300. EPA plans to initiate the process of proposing 

a national primary drinking water regulation for perchlorate (see response to comment code 6120). 

Commenter Name: Caroline Baier-Anderson, PhD 

Commenter Organization: Health Scientist, Environmental Defense Fund PUBLIC 

EPA Document ID: EPA-HQ-OW-2008-0692-0649 

EPA Comment ID: 19992 

EPA Comment Code: 1300 

Comment: October 27, 2008 

Mr. Eric Burneson Office of Ground Water and Drinking Water Standards and Risk Management 

Division Environmental Protection Agency 1200 Pennsylvania Avenue, NW Washington, DC 

20460 Re: Request for extension of comment period for Docket Identification (ID): EPA- HQOW-2008- 0692- Preliminary Regulatory Determination on Perchlorate 

Dear Mr. Burneson: 

On October 10, 2008, EPA published a Federal Register notice announcing the opening of a 30-day 

comment period on its preliminary regulatory determination on perchlorate. We have concerns 

regarding the proposed regulatory determination, in particular the unprecedented use of a 

pharmacodynamic model to justify the exceedance of the reference dose and we believe this 

introduces complexity into the evaluation of the standard that merits more than just 30 days for 

judicious scientifically-sound public comment. We therefore request that the comment period be 

extended by 60 days, so comments will be due 90 days from the October 10, 2008 notice, on January 

10, 2009. 

Thank you for considering this request. 

Sincerely, Caroline Baier-Anderson, Ph.D. Health Scientist 

Response: See the response to comment code 1300. 

Commenter Name: Luis Olmedo Vélez 

Commenter Organization: Comité Cívico del Valle, Inc. 

EPA Document ID: EPA-HQ-OW-2008-0692-0652 

EPA Comment ID: 19995 

EPA Comment Code: 1300 

Comment: Among profit and non-profit organizations that take environmental issues seriously, 

there are only several people who are qualified to measure and evaluate EPA’S findings and 

conclusions. Therefore, a 30-day comment period is far too short a time period to take action 

against any rulings that may be detrimental to the water supply. We ask that the EPA extend the 

preliminary regulatory determination date to 90-days. 

Sincerely, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 33 of 1099

 Luis Olmedo Vélez Executive Director Comité Cívico del Valle, Inc. Center for Health Education, 

Prevention and Advocacy 

Response: See the response to comment code 1300. 

Commenter Name: Steven Brittle 

Commenter Organization: Don't Waste Arizona 

EPA Document ID: EPA-HQ-OW-2008-0692-0653 

EPA Comment ID: 19996 

EPA Comment Code: 1300 

Comment: October 26, 2008 

Eric Burneson Office of Ground Water and Drinking Water Standards and Risk Management U.S. 

Environmental Protection Agency Ariel Rios Building 1200 Pennsylvania Avenue, N. W. Mail Code: 

4607M Washington, DC 20460 

Dear Sir: 

Don’t Waste Arizona (DWAZ) is a non-profit environmental organization especially concerned 

about toxics issues. 

DWAZ is concerned that EPA's failure to regulate perchlorate, as well as its unprotective proposed 

health reference level, will adversely affect the health and development of hundreds of thousands, 

perhaps millions of American children, including those in Arizona. It has taken EPA years, with its 

extensive resources, to come to its conclusions. Its findings are complex and controversial. We 

cannot afford to have this decision rushed out the door, in the waning days of the current 

administration, without giving impacted communities sufficient time to comment. 

Organizations that advocate for public health and environmental protection have few people with 

the expertise, resources, and time to evaluate EPA's findings, review continuously emerging 

scientific literature, and prepare comments. DWAZ therefore calls upon EPA to extend the 30-day 

comment period on its October 10, 2008 Preliminary Regulatory Determination on Perchlorate to 

90 days. 

Sincerely, 

 Stephen M Brittle President Don’t Waste Arizona 6205 South 12th Street Phoenix, AZ 85042 602-

268-6110 

 Cc: EPA Administrator Stephen Johnson 

Response: See the response to comment code 1300. EPA plans to initiate the process of proposing 

a national primary drinking water regulation for perchlorate (see response to comment code 6120). 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0682 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 34 of 1099

EPA Comment ID: 20023 

EPA Comment Code: 1300 

Comment: I request the comment period be extended for 90 days to give those a chance to review 

the information and offer their voice about it. re. the regulatory determination on 

PERCHLORATE......epa -hq--ow-2008-0692 

Response: See the response to comment code 1300. 

Commenter Name: Luis Olmedo Vélez 

Commenter Organization: Comité Cívico del Valle, Inc., Center for Health Education, Prevention 

and Advocacy 

EPA Document ID: EPA-HQ-OW-2008-0692-0736 

EPA Comment ID: 20048 

EPA Comment Code: 1300 

Comment: Among profit and non-profit organizations that take environmental issues seriously, 

there are only several people who are qualified to measure and evaluate EPA’S findings and 

conclusions. Therefore, a 30-day comment period is far too short a time period to take action 

against any rulings that may be detrimental to the water supply. We ask that the EPA extend the 

preliminary regulatory determination date to 90-days. 

Sincerely, 

 Luis Olmedo Vélez Executive Director Comité Cívico del Valle, Inc. Center for Health Education, 

Prevention and Advocacy 

Response: See the response to comment code 1300. 

Commenter Name: Lynn and Paul Thorp and Schwartz 

Commenter Organization: Clean Water Action (CWA) 

EPA Document ID: EPA-HQ-OW-2008-0692-0750 

EPA Comment ID: 20056 

EPA Comment Code: 1300 

Comment: October 28, 2008 Eric Burneson U.S. Environmental Protection Agency Arid Rios 

Building 120o Pennsylvania Ave. NW Washington DC 20460 Re: Request for Extension of 

Comment Period for Preliminary Regulatory Determination on Perchlorate Public Noticed October 

to, 2008 at 73 Fed. Reg. 60262 Docket Identification (ID): EPA-HQ-OW-2008-00692 

Dear Mr. Burneson: On behalf of our more than 1.2 million members, we request an extension of 

the public comment period for the Preliminary Regulatory Determination on Perchlorate of at least 

60 days beyond the November to deadline, for a total extension of not less than qo days to January 

to, 2009. The proposed Preliminary Regulatory Determination on Perchlorate raises complex issues 

which require more time to be sufficiently reviewed. Furthermore, the Determination makes 

conclusions which contradict those made by several states, such as Massachusetts and New Jersey, 

which have reviewed the same issue and have set a drinking water standard for percblorate. The 

Determination raises serious implications for human health. These include the exposure to 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 35 of 1099

perchlorate by millions of Americans in their food and the adverse effects of perchlorate exposure 

to those most at risk, including infants, toddlers, and pregnant women. Additional time will enable 

us to analyze and make informed comments regarding the Preliminary Determination. Please make 

this letter part of the comment record for the Preliminary Determination. Thank you for your 

attention to this request. 

Sincerely, 

Lyn Thorp National Campaign Coordinator Ext. 109 

Paul Schwartz National Policy Coordinator Ext. 105 

CC: Stephen Johnson, Administrator, US Environmental Protection Agency [Via First Class Mail 

and Fax 202-501-1450] 

Response: See the response to comment code 1300. 

Commenter Name: Robin Mark Freeman 

Commenter Organization: Merritt College 

EPA Document ID: EPA-HQ-OW-2008-0692-0662 

EPA Comment ID: 20237 

EPA Comment Code: 1300 

Comment: Organizations that advocate for public health and environmental protection have few 

people with the expertise, resources, and time to evaluate EPA's findings, review continuously 

emerging scientific literature, and prepare comments. We therefore call upon EPA to extend the 30-

day comment period on its October 10, 2008 Preliminary Regulatory Determination on Perchlorate 

to 90 days. 

Sincerely, Prof. Robin Mark Freeman, Co-Director Institute for Sustainable Policy Studies Merritt 

College, Oakland , CA 

 

Cc: EPA Administrator Stephen Johnson 

Response: See the response to comment code 1300. 

Commenter Name: Tatjana and Jeremy Thomas 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0669 

EPA Comment ID: 20243 

EPA Comment Code: 1300 

Comment: Water Docket Environmental Protection Agency Mailcode: 2822T 1200 Pennsylvania 

Ave., NW Washington, DC 20460 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 36 of 1099

 Docket Identification (ID) Number: EPA-HQ-OW-2008-0692 Preliminary Regulatory 

Determination on Perchlorate Re: Request for extension of comment period 

 I am writing to express my concern regarding the EPA's failure to regulate perchlorate, as well as 

the proposed reference level, which fails to protect - and will adversely affect -- the health and 

development of hundreds of thousands, perhaps millions of American children. 

EPA has spent a number of years researching perchlorate and developing its conclusions - which are 

considered highly controversial and complex. They require, therefore, the time for measured and 

throughful public response. 

We cannot afford to have this decision rushed through, in the last days of the current 

administration, and leaving those communities that face the greatest risk without enough time to 

comment. 

It takes time for public and community groups to evaluate EPA's findings, review the ever-changing 

scientific literature, and prepare comments. 

I therefore request that the Sincerely, EPA extend the 30-day comment period on its October 10, 

2008 Preliminary Regulatory Determination on Perchlorate to 90 days. 

Sincerely, 

 Tatjana Thomas 

Response: See the response to comment code 1300. EPA plans to initiate the process of proposing 

a national primary drinking water regulation for perchlorate (see response to comment code 6120). 

Commenter Name: D. Manzullo 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0676 

EPA Comment ID: 20250 

EPA Comment Code: 1300 

Comment: Allow more time for all the appropriate researchers and scientists to comment on the 

harm these chemicals are doing to humans, living creatures and plant life! 

Response: See the response to comment code 1300. 

Commenter Name: S. Smolen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0679 

EPA Comment ID: 20255 

EPA Comment Code: 1300 

Comment: Because the decision of whether or not to implement a national maximum contaminant 

level is so important and far reaching, I respectfully request that the EPA extend the comment 

period to 90+ days (an additional 60 days past the current deadline of November 10th) in order to 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 37 of 1099

allow groups wishing to submit comments on the decision sufficient time to review and respond to 

the evidence supporting the EPA's position. 

Sincerely, 

Stephanie Smolen Former San Gabriel Valley resident EPA Region 9, Superfund Areas 1 & 2, 

California EPA ID#’s CAD980677355 & CAD980818512 respectively 

Response: See the response to comment code 1300. 

Commenter Name: Kathy M. Kinsey 

Commenter Organization: Maryland Department of the Environment 

EPA Document ID: EPA-HQ-OW-2008-0692-1421 

EPA Comment ID: 20426 

EPA Comment Code: 1300 

Comment: Kathy M. Kinsey Senior Policy Advisor Maryland Department of the Environment 410-

537-3897 kkinsey@mde.state.md.us Re: Docket ID No. EPA-HQ-OW-2008-0692 Comments on 

Perchlorate Determination November 7, 2008 

The Maryland Department of the Environment ("Department") submits the following comments on 

EPA's preliminary regulatory determination on perchlorate. 

Request for Extension of the Public Comment Period 

As a preliminary matter, the Department requests that EPA extend the public comment period. 

EPA's preliminary determination not to set a regulatory standard for perchlorate in drinking water 

has serious public health implications for the millions of people potentially exposed to perchlorate 

through public drinking water systems. EPA's determination was based on an analysis of highly 

complex data and an unprecedented application of published models with adjustments that have not 

undergone peer review. A thorough and thoughtful review of EPA's analysis and preliminary 

determination requires more than the 30 days currently allotted by EPA. The Department, therefore, 

requests that EPA extend the public comment period by a minimum of 60 days beyond the current 

November 10, 2008 deadline for submitting comments. 

Response: See the response to comment code 1300. 

Commenter Name: Kathy M. Kinsey 

Commenter Organization: Maryland Department of the Environment 

EPA Document ID: EPA-HQ-OW-2008-0692-1421 

EPA Comment ID: 20429 

EPA Comment Code: 1300 

Comment: For the foregoing reasons, the Department urges EPA to both extend the public 

comment period on its preliminary determination by an additional 60 days beyond the current 

November 10, 2008 deadline, and set a federal drinking water standard for perchlorate. 

Response: See the response to comment code 1300. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Commenter Name: Vicky and Bll Clary 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0622 

EPA Comment ID: 20465 

EPA Comment Code: 1300 

Comment: EPA has spent a number of years researching perchlorate and developing its 

conclusions - which are considered highly controversial and complex. They require, therefore, the 

time for measured and throughful public response. 

We cannot afford to have this decision rushed through, in the last days of the current 

administration, and leaving those communities that face the greatest risk without enough time to 

comment. Every American affected should have a voice in this issue and it shouldn't be decided by 

the military or pushed through before we are all given a chance to comment or even to become 

aware of the problem. 

It takes time for public and community groups to evaluate EPA's findings, review the ever-changing 

scientific literature, and prepare comments. 

I therefore request that the EPA extend the 30-day comment period on its October 10, 2008 

Preliminary Regulatory Determination on Perchlorate to 90 days. 

Sincerely, 

Vicky and Bll Clary 

Response: See the response to comment code 1300. 

Commenter Name: Nancy Yoke 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0621 

EPA Comment ID: 20560 

EPA Comment Code: 1300 

Comment: I am writing to express my concern regarding the EPA's failure to regulate perchlorate, 

as well as the proposed reference level, which fails to protect - and will adversely affect -- the health 

and development of hundreds of thousands, perhaps millions of American children. 

EPA has spent a number of years researching perchlorate and developing its conclusions - which are 

considered highly controversial and complex. They require, therefore, the time for measured and 

throughful public response. 

We cannot afford to have this decision rushed through, in the last days of the current 

administration, and leaving those communities that face the greatest risk without enough time to 

comment. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 39 of 1099

It takes time for public and community groups to evaluate EPA's findings, review the ever-changing 

scientific literature, and prepare comments. 

I therefore request that the EPA extend the 30-day comment period on its October 10, 2008 

Preliminary Regulatory Determination on Perchlorate to 90 days. 

Sincerely, 

Nancy Yoke 

Response: See the response to comment code 1300. EPA plans to initiate the process of proposing 

a national primary drinking water regulation for perchlorate (see response to comment code 6120). 

Commenter Name: Caroline Baier-Anderson 

Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1534 

EPA Comment ID: 20637 

EPA Comment Code: 1300 

Comment: November 13, 2008 

Mr. Eric Burneson Office of Ground Water and Drinking Water Standards and Risk Management 

Division Environmental Protection Agency 1200 Pennsylvania Avenue, NW Washington, DC 

20460 

Re: Second request for extension of comment period for Preliminary Regulatory Determination on 

Perchlorate, Docket ID EPA-HQ-OW-2008-0692 

Dear Mr. Burneson: 

On October 10, 2008, EPA published a Federal Register notice announcing the opening of a 30-day 

comment period on its preliminary regulatory determination on perchlorate and on October 27th we 

submitted to the docket a letter requesting that the comment period be extended for 60 days (EPAHQ- OW-2008-0692-0649). On November 7, EDF was notified by telephone that the comment 

period has been extended only 18 days, until November 28, 2008, but that the notice for this 

extension would not be entered into the Federal Register until Wednesday, November 12, two days 

after the initial deadline for comments. 

We believe that this extension is inadequate, for the following reasons: 

1. As noted in our previous letter, the Preliminary Regulatory Determination on Perchlorate is based 

on the virtually unprecedented use of a pharmacodynamic model developed by industry to justify 

the exceedance of the reference dose. This model and its novel application introduce significant 

complexity into the evaluation of the standard, which merits more than just 30 days for judicious 

scientifically-sound public comment. 

2. Providing only an 18-day extension to this comment period is far shorter than and hence not 

consistent with other extensions EPA has granted. For example: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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* Three extensions were made to the comment period for the "Draft List of Initial Pesticide Active 

Ingredients and Pesticide Inerts to be Considered for Screening under the Federal Food, Drug, and 

Cosmetic Act", consisting of 60 days, 45 days, and 42 days, for a total of 147 days (EPA-HQ-OPPT2004-0109; FRL-8346-5). 

* The comment period for the re-registration of Chloropicrin, Dazomet, Metam Sodium/Potassium, 

and Methyl Bromide was extended for 45 days (EPA-HQ- OPP-2008-0518; FRL-8380-5). 

* The comment period for the "Proposed Rule for Standards of Performance for Portland Cement 

Plants" was also extended by 45 days (EPA-HQ-OAR-2008-0260; FRL-8703-2). 

3. Since presumably you could only contact those commenters whom you knew or anticipated were 

planning to submit comments, the failure to post the notice of the extension in a timely manner 

placed any commenters not known to you at a significant disadvantage. (An incorrect docket 

number published in the initial notice also likely serves to further confuse and delay commenters.) 

We therefore reiterate our request that the comment period be extended by at least 60 days, with 

comments due no earlier than 90 days from the October 10, 2008 notice, or January 10, 2009. We 

consider this request to be both reasonable and justified by the complexity of and importance of the 

decision. It is also more in line with other extensions the Agency has granted. 

We request a reply at your earliest convenience. 

Thank you again for your consideration. 

Sincerely, 

Caroline Baier-Anderson, Ph.D. Health Scientist 

Response: EPA considered this request for a second extension beyond the revised November 28, 

2008 extension but concluded that a further extension beyond the 49 days provided was not needed 

for commenters to consider the information in the 1 page Federal Register Notice and would 

unnecessarily delay decision making. 

Commenter Name: Deborah Swackhamer 

Commenter Organization: Science Advisory Board 

EPA Document ID: EPA-HQ-OW-2008-0692-1749 

EPA Comment ID: 20660 

EPA Comment Code: 1300 

Comment: As you know, the SAB operates under the requirements of the Federal Advisory 

Committee Act for advance notice of public meetings. Therefore, the SAB will not be able to 

provide you with our comments regarding the scientific basis of this determination in time to meet 

the Agency’s deadline of November 10, 2008. Accordingly, the SAB urges the Agency to consider 

extending the public comment period thereby allowing us to provide comments for the Agency’s 

consideration in making the final regulatory determination on perchlorate. Thank you in advance for 

your consideration. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 41 of 1099

Sincerely, 

/Signed/ Dr. Deborah L. Swackhamer, Chair Science Advisory Board 

/Signed/ Dr. Joan Rose, Chair SAB Drinking Water Committee 

cc: Marcus Peacock, Deputy Administrator Ben Grumbles, Assistant Administrator, Office of Water 

Cynthia Dougherty, Office of Water 

Response: Administrator Stephen Johnson replied to the SAB on January 9, 2009. The letter is 

available in EPA’s docket ID No. EPA-HQ-OW-2009-0297 for this notice 

Commenter Name: S. Quezada 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1840 

EPA Comment ID: 20729 

EPA Comment Code: 1300 

Comment: October 24, 2008 Water Docket Environmental Protection Agency Mailcode: 2822T 

1200 Pennsylvania Ave., NW Washington, DC 20460 

Docket Identification (ID) Number: EPA-HQ-OW-2008-0692 Preliminary Regulatory 

Determination on Perchlorate Re: Request for extension of comment period 

Americans cannot afford to have a final determination on perchlorate's safety rushed through in 

light of the high scientific controversy surrounding the matter. Therefore, I request an extension of 

public comments from 30 days to 90 days. This extension would be appropriate and prudent given 

the high scientific and academic controversy over the matter. Even the mere appearance of 

"rushing" to a final determination is inappropriate and should be dispelled by providing Americans 

the opportunity to fully evaluate and meaningfully comment on the EPA's proposed action. 

The EPA has spent a number of years researching perchlorate and developing its conclusions. To 

now, turn around and provide the American public 30 days for public comment on a complex 

matter is both unfair and questionable as to whether the EPA truly seeks to obtain the public's 

comments (to which the EPA must articulate a rational response in its final adoption of any 

perchlorate's final determination). 

Sincerely, S. Quezada 416 Ridgeview Ave Iowa City, Iowa 52246 

Response: See the response to comment code 1300. 

Commenter Name: Andrew E. Stevenson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1878 

EPA Comment ID: 20766 

EPA Comment Code: 1300 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 42 of 1099

Comment: Please extend the public comment for this important environmental issue, in order to 

give the citizens of our country time to weigh in on this. 

Sincerely yours, Andrew E. Stevenson 311-A East Bellefonte Ave. Alexandria, VA 22301 

Response: See the response to comment code 1300. 

Commenter Name: Mary Moore 

Commenter Organization: Lindon Park Neighborhood Association (LPNA) 

EPA Document ID: EPA-HQ-OW-2008-0692-2002 

EPA Comment ID: 20833 

EPA Comment Code: 1300 

Comment: U.S. Environmental Protection Agency Office of Water Docket (Mail Code: 2822T) 

1200 Pennsylvania Ave., NW Washington, DC 20460 

Ref: Docket EPA-HQ-OW-2008-068 Drinking Water: Preliminary Regulatory Determination on 

Perchlorate 

To Whom It May Concern: 

The Lindon Park Neighborhood Association (LPNA) respectfully requests that EPA extend the 

public comment period for 60 days to allow sufficient time for a thorough review of the documents 

used by EPA in reaching the preliminary determination not to issue a national primary drinking 

water regulation. 

Response: See the response to comment code 1300. 

Commenter Name: D'Lanie Blaze 

Commenter Organization: TheAeroSpace 

EPA Document ID: EPA-HQ-OW-2008-0692-0641 

EPA Comment ID: 20892 

EPA Comment Code: 1300 

Comment: It the EPA is indeed motivated by an ethical commitment to safety, it will recognize the 

error in this decision. It will also facilitate public awareness and extend an obvious invitation to take 

part in this process, recognizing that 90+ days is required for the public to exercise this right in an 

informed capacity. 

 Sincerely, 

D'Lanie Blaze Mission Control : TheAeroSpace IGNITE YOUR INTELLECT : CONNECT! 

http://www.TheAeroSpace.org 

 Links of Interest : SSFL 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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http://www.ACMELA.org http://www.RocketdyneArchives.com http://www.dtsc-ssfl.com/ 

http://www.CleanUpRocketdyne.org http://www.CommitteeToBridgeTheGap.org 

Response: See the response to comment code 1300. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20918 

EPA Comment Code: 1300 

Comment: In light of the extremely short initial public comment period of 30 days and the 

complexity of the EPA assessment, EWG and other environmental groups requested a 60- day 

extension of the comment period. On November 10th, EPA granted an 18-day extension to the 

initial comment period. EWG respectfully requests that the 60- day extension that we had initially 

requested be granted to allow for a more thorough review of EPA’s assessment. 

Response: See the response to comment code 1300. 

Commenter Name: Ron Curry 

Commenter Organization: New Mexico Environment Department 

EPA Document ID: EPA-HQ-OW-2008-0692-1796 

EPA Comment ID: 20930 

EPA Comment Code: 1300 

Comment: November 26, 2008 

Stephen L. Johnson Administrator United States Environmental Protection Agency c/o Water 

Docket Mailcode 2822T 1200 Pennsylvania, N.W. Washington, D.C. 20460 

Re:Comments on Preliminary Regulatory Determination on Perchlorate Docket ID No. EPA-HQOW-2008-0692 

Dear Administrator Johnson: 

By this letter I am submitting the comments of the New Mexico Environment Department on the 

Preliminary Determination on Perchlorate that the United States Environmental Protection Agency 

(EPA) issued on October 3, 2008. 73 Fed. Reg. 60262 (Oct.10, 2008). Although EPA initially 

requested comments by November 10, 2008, the agency subsequently extended the comment period 

through November 28, 2008. 73 Fed. Reg. 66895 (Nov. 12, 2008). The Environment Department 

appreciates the opportunity to comment on this important regulatory decision, and the extension of 

time to submit these comments. 

Response: No response necessary to the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 44 of 1099

EPA Comment ID: 21091 

EPA Comment Code: 1300 

Comment: II. The EPA Should Publish its Final Determination as Soon as Possible 

In the Federal Register notice, EPA has set a timeline for public comment, a final decision, and the 

possible decision to set a Health Advisory (HA). EPA's timeline for a final determination is wise for 

two principal reasons. First, the 45-day period provides ample time for the public to review EPA 

documents and submit comments as EPA has offered substantial opportunities for public comment 

on this matter. EPA previously provided a 60-day public comment period on the Contaminant 

Candidate List 2 (CCL) preliminary regulatory determinations for 11 chemicals issued May 1, 2007 

via publication in the Federal Register as well as on its website.[FN1: 72 Fed. Reg. 24016 (2007) 

(published May 1, 2007).] In that publication, EPA also extended the opportunity to the public to 

comment on perchlorate. The PSG and other organizations commented extensively on that notice. 

EPA, indicating it was not issuing a determination at that time, discussed the various scientific and 

technical data being reviewed and considered by the agency, including the National Academy of 

Sciences (NAS) report, the Unregulated Contaminant Monitoring Rule 1 (UCMR) occurrence data, 

and options to use data to establish the relative source contribution (RSC). The agency also 

identified options for potential methodologies that could be employed to make a determination, 

including the option of using the NHANES and UCMR 1 data. EPA has selected that approach as 

its basis for its preliminary determination. Thus EPA has offered the public multiple opportunities 

for public comment, more than most substances on the CCL for which EPA has made a 

determination. 

Response: See the response to comment code 1300. 

Commenter Name: Teresa Jordan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2086 

EPA Comment ID: 21109 

EPA Comment Code: 1300 

Comment: Mr. Grumbles and Mr. Burneson, I thank the USEPA, and persons who may have made 

the request, for extending the public comment period. I had not written sooner because I have had 

my hands full adressing: California State Water Resources Control Board water issues, the Los 

Angeles Regional Water Quality Control Board's Basin Plan Triennial Review, the California 2009 

Water Plan Update (Initial, Working, and Pre-Administrative Draft Plans for the South Coast 

Hydrologic Region-Ventura and Los Angeles Counties), and Alaska's Seafood Processors general 

NPDES Permit. 

Sincerely, 

Mrs. Teresa Jordan 

[see attachments Docket ID EPA-HQ-OW-208-0692-2086] 

Response: No response necessary to the information provided by the commenter. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 1500 EPA's handling of comments on the October 2008 

FR Notice 

Individual Comments 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection (MassDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0495 

EPA Comment ID: 28858 

EPA Comment Code: 1500 

Comment: Docket ID No. EPA-HQ-OW-2009-0297 Drinking Water: Perchlorate Supplemental 

Request for Comments. U.S. Environmental Protection Agency. 

The Massachusetts Department of Environmental Protection Office of Research and Standards is 

pleased to provide the attached comments regarding the U.S. Environmental Protection Agency's 

(EPA) decision to reconsider its approach to analyzing scientific data related to perchlorate in 

drinking water. The Wednesday, August 19, 2009 Federal Register announcement includes a 

summary of the major comments EPA received regarding its October 10, 2008 preliminary 

regulatory determination to not regulate perchlorate in drinking water. This includes comments on 

why the proposed 15 ppb health advisory is not protective of children's health. These comments 

provide a strong basis for EPA's appropriate decision to consider a broader range of alternatives for 

interpreting the health data, the level of health concern, the frequency of occurrence of perchlorate 

in drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard. The Commonwealth of Massachusetts' Department of Environmental Protection 

(MassDEP) is pleased to provide comments on several of the issues that are the focus of this 

Federal Register announcement and is available to further consult with you or answer any questions 

you may have on our comments. Our comments are organized by issues described in specific 

sections of the Federal Register and are detailed in the attachment. Thank you. 

Attachment 

 September 17, 2009 

Docket ID No. EPA-HQ-OW-2009-0297 Drinking Water: Perchlorate Supplemental Request for 

Comments U.S. Environmental Protection Agency 

 We highly commend the U.S. Environmental Protection Agency's (EPA) decision to reconsider its 

approach to analyzing scientific data related to perchlorate in drinking water. The Wednesday, 

August 19, 2009 Federal Register announcement includes a summary of the major comments EPA 

received regarding its October 10, 2008 preliminary regulatory determination to not regulate 

perchlorate in drinking water. This includes comments on why the proposed 15 ppb health advisory 

is not protective of children's health. These comments provide a strong basis for EPA's appropriate 

decision to consider a broader range of alternatives for interpreting the health data, the level of 

health concern, the frequency of occurrence of perchlorate in drinking water, and the opportunity 

for health risk reduction through a national primary drinking water standard. The Commonwealth of 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 46 of 1099

Massachusetts' Department of Environmental Protection (MassDEP) is pleased to provide 

comments on several of the issues that are the focus of this Federal Register announcement and is 

available to further consult with you or answer any questions you may have on our comments. Our 

comments are organized by issues described in specific sections of the Federal Register. 

Response: No response is necessary to the information provided by the commenter. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 1600 Length of the comment period following August 

2009 FR Notice 

Response to Comment Code 1600: A number of commenters requested an extension to EPA's 30 

day comment period on the Agency's August 19, 2009 Federal Register Notice (74 FR 41883, 

August 19, 2009). In response to these requests, the Agency extended the comment period until 

October 8, 2009, thereby providing commenters with 51 days to review the information contained 

in the Federal Register Notice and prepare comments. EPA received comment letters from over 

6,000 individuals and organizations on the August 19, 2009 Federal Register Notice. 

Individual Comments 

Commenter Name: David L. Thomas 

Commenter Organization: National Sorghum Producers 

EPA Document ID: EPA-HQ-OW-2009-0297-0336 

EPA Comment ID: 28447 

EPA Comment Code: 1600 

Comment: September 14, 2009 

Eric Burneson Office of Ground Water and Drinking Water Standards and Risk Management 

Division Environmental Protection Agency 1200 Pennsylvania Avenue, NW Washington, DC 

20460 

Re: Request for extension of comment period for Docket Identification (ID) EPA- HQ-OW-2008-

0692-Perchlorate Supplemental Request for Comments 

Dear Mr. Burneson, 

In the Federal Register on August 19, 2009, EPA published a notice seeking comments under a 30 

day public comment period on "additional approaches available for analyzing data related to EPA's 

perchlorate regulatory determination." 

The sorghum industry has been using the chemical perchlorate for many years. It is essential to 

producers because it aids in the dry down process and allows crops to be harvested properly without 

additional moisture. 

Even though perchlorate is naturally occurring, EPA states in the August 19, 2009 Federal Register 

notice that the "additional alternatives under consideration could result in health reference levels 

which are much lower than the level identified in the October 2008 notice." 

Since the public comments collected under this Federal register could have serious affects on 

sorghum producers, the National Sorghum Producers asks that EPA establish the appropriate 

science based methodology before proceeding with a regulatory determination. EPA has raised a 

number of complicated scientific issues in this Federal Register notice that will impact our 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 48 of 1099

producers. On their behalf, we are requesting that the comment period be extended by 60 days to 

allow for a more thorough analysis of the issues raised. 

Thank you for your consideration. 

Sincerely, David L. Thomas 

Response: See response to comment code 1600. 

Commenter Name: Larry Cummings 

Commenter Organization: Perchlorate Study Group (PSG) 

EPA Document ID: EPA-HQ-OW-2009-0297-0417 

EPA Comment ID: 28471 

EPA Comment Code: 1600 

Comment: The Perchlorate Study Group acknowledges that EPA has placed a notice on their 

website granting a 15-day extension to the comment period for Docket EPA-HQ- OW-2009-0297 

and intends to submit detailed comments by the conclusion of the extension. 

 September 18, 2009 

U.S. Environmental Protection Agency Office of Water Docket (Mailcode 2822T) 1200 

Pennsylvania Avenue, NW Washington, DC 20460 

Re: Comments in Response to EPA Drinking Water: Perchlorate Supplemental Request for 

Comments [EPA-HQ-OW-2009-0297] 

The Perchlorate Study Group (PSG) acknowledges that EPA has posted on its website a statement 

that the comment period for Docket EPA-HQ-OW-2009-0297 has been extended for a period of 

15 days. This action will allow us to submit more detailed responses to the questions that have been 

raised in the August 19 "Drinking Water: Perchlorate Supplemental Request for Comments" for 

EPA's consideration. We look forward to receiving formal notice of this action next week and will 

submit our comments by the 15-day closing date provided in the Federal Register notice announcing 

the extension of the comment period. 

We welcome the opportunity to meet with EPA staff to explain our position in greater detail. Please 

feel free to contact me at 3883 Howard Hughes Parkway, Suite 700, Las Vegas, NV 89169. 

Sincerely, Larry Cummings Chairman Perchlorate Study Group 

Response: No response necessary to the information provided by the commenter. 

Commenter Name: Stephen Haterius 

Commenter Organization: The National Association of State Departments of Agriculture 

(NASDA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0500 

EPA Comment ID: 28484 

EPA Comment Code: 1600 
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Comment: Please see the attached letter to Assistant Administrator Silva from the National 

Association of State Departments of Agriculture requesting a 30-day extension of the comment 

period in response to EPA's supplemental request for comments on perchlorate. 

Attachment 

 September 18, 2009 

The Honorable Peter S. Silva Assistant Administrator for Water U.S. Environmental Protection 

Agency 1200 Pennsylvania Avenue, NW Washington, DC 20460 

Re: Perchlorate Supplemental Request for Comments (Docket ID No. EPA-HQ- OW-2009-0297) 

Dear Assistant Administrator Silva: 

The National Association of State Departments of Agriculture (NASDA) respectfully requests a 30-

day extension of the public comment period for the supplemental request for comments on 

perchlorate so that state regulators, as well as impacted sectors of our nation’s agriculture economy, 

have an appropriate opportunity to review the approach EPA has taken in its evaluation of 

perchlorate. 

NASDA represents the commissioners, secretaries, and directors of the state departments of 

agriculture in all fifty states and four U.S. territories. NASDA'S members are responsible for a wide 

range of public health programs from food safety to combating the spread of disease. Moreover, as 

co-regulators with EPA, NASDA’s members are the lead state agencies responsible for 

administering, implementing and enforcing the laws regulating the production, labeling, distribution, 

sale, use and disposal of pesticides. This broad range of responsibilities gives our members a 

significant basis of relevant expertise in responding to the request for comment in the August 19, 

2009 Federal Register. 

We are concerned that the approaches EPA described in the August 19, 2009 Federal Register are a 

significant departure from the traditional methods by which EPA has analyzed scientific and 

technical data. Previous opportunities for public comment on the traditional approaches for 

analyzing data related to perchlorate have allowed for comments periods of up to 60 days. In light of 

this, and because the approaches detailed in the August 19, 2009 Federal Register differ significantly 

from those used for perchlorate and other Contaminant Candidates, an additional 30 days is 

necessary. 

Response: See response to comment code 1600. 

Commenter Name: Stephen Haterius 

Commenter Organization: National Association of State Departments of Agriculture (NASDA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0664 

EPA Comment ID: 28547 

EPA Comment Code: 1600 

Comment: October 8, 2009 
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Water Docket U.S. Environmental Protection Agency Mailcode: 2922T 1200 Pennsylvania Avenue, 

NW Washington, DC 20460 

Re: Perchlorate Supplemental Request for Comments (Docket ID No. EPA-HQ-OW-2009-0297) 

Dir Sir/Madam: 

The National Association of State Departments of Agriculture (NASDA) represents the 

commissioners, secretaries, and directors of the state departments of agriculture in all fifty states and 

four U.S. territories. NASDA'S members are responsible for a wide range of public health programs 

from food safety to combating the spread of disease. Moreover, as co-regulators with the 

Environmental Protection Agency (EPA), NASDA's members are the lead state agencies 

responsible for administering, implementing and enforcing the laws regulating the production, 

labeling, distribution, sale, use and disposal of pesticides. 

This broad range of responsibilities gives our members a significant basis of relevant expertise in 

responding to EPA's August 19, 2009 request for comment on alternative approaches to interpreting 

data related to EPA's earlier regulatory determination for perchlorate in drinking water. The 

comments NASDA is submitting today are intended to supplement comments submitted on 

September 18, 2009 in which NASDA requested additional time to review the approaches outlined 

by EPA. 

Response: No response necessary to the information provided by the commenter. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 51 of 1099

EPA Comment Code: 2000 Perchlorate Health Effects 

Response to Comment Code 2000: EPA used the January 2005 National Research Council (NRC) 

study “Health Implications of Perchlorate Ingestion,” a review of the state of the science regarding 

potential adverse health effects of perchlorate exposure and mode of action for perchlorate toxicity 

(NRC, 2005) in developing this regulatory determination. The NRC recommended that EPA use 

data from the Greer et al. (2002) human clinical study as the basis for deriving a reference dose for 

perchlorate (NRC, 2005). Although the NRC committee concluded that hypothyroidism is the first 

adverse effect in the continuum of effects of perchlorate exposure, NRC recommended that “the 

most health-protective and scientifically valid approach” was to base the perchlorate RfD on the 

inhibition of iodide uptake by the thyroid, which the NRC considered a non-adverse effect (NRC, 

2005). The NRC recommended that EPA apply an intraspecies uncertainty factor of 10 to the no 

observed effect level (NOEL)1, to account for differences in sensitivity between the healthy adults in 

the Greer et al., (2002) study and the most sensitive population, fetuses of pregnant women who 

might have hypothyroidism or iodide deficiency. They viewed this as conservative and protective of 

health given that the NOEL is based on a non-adverse effect (iodide uptake inhibition), which 

precedes the adverse effect in a continuum of possible effects of perchlorate exposure. The NRC 

also noted that “any decrease (in thyroid hormone) is potentially more likely to have adverse effects 

in sensitive populations (people with thyroid disorders, pregnant women, fetuses, and infants). 

EPA’s Integrated Risk Information System (IRIS) adopted the NRC’s recommendations resulting in 

an RfD of 0.7 μg/kg/day (USEPA, 2005b). 

Individual Comments 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0469 

EPA Comment ID: 19898 

EPA Comment Code: 2000 

Comment: I think you should regulate perchlorate in drinking water unless you know the following: 

1. That perchlorate and thiocyanate don't have a synergistic effect within the thyroid by virtue of 

perchlorate inhibiting the conversion of thiocyanate to sulfate within the thyroid. Such an effect 

would increase the level of toxic sulfite in the thyroid. EPA chemist Ed Urbanski told me the EPA 

considered molybdenum co-factor enzymes, and perhaps subunits of those enzymes (sulfite oxidase 

is a subunit of nitrate reductase) to be perchlorate targets. 

2. That adhesion of perchlorate to albumin and similar proteins in the blood and skin, which occurs 

in the blood before inhibition of the sodium iodide symporter and continues in the skin after 

perchlorate is cleared from the blood and thyroid, never forms a hapten that triggers an autoimmune 

reaction similar to iododerma and bromoderma. This seemed pertinent to Burleson's skin contact 

 

1 No observed effect level (NOEL) - an exposure level at which there are no statistically or biologically significant 

increases in the frequency or severity of any effect between the exposed population and its appropriate control. 
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sensitivity data in the 2002 external peer review, but there was no discussion of these traits of 

chaotropic salts in the EPA evaluation. 

3. That perchlorate doesn't inhibit the effectiveness of defensin at its positively-charged 6-cysteine 

structure. Such an effect may help explain the aplastic anemia reported from medicinal doses of 

perchlorate by promoting infection by B-19 parvovirus. B-19 parvovirus is also associated with 

thyroid autoimmunity and thyroid cancer. 

4. That pendrin is not the primary means of excreting perchlorate from the kidneys. If pendrin is the 

primary means of excreting perchlorate, then persons in a state of acidosis or low blood bicarbonate 

would retain perchlorate and be more vulnerable to its effects. Premature infants, infants with 

diarrhea, smokers, and adults with poorly managed diabetes in particular fit in this category of 

patient. 

5. That extra-thyroidal sodium iodide symporter in the salivary glands, bronchial epithelium, gastric 

mucosa,and elsewhere in the body is not more sensitive to perchlorate than thyroidal sodium iodide 

symporter in the thyroid that is upregulated by TSH. Interference with proper function of nonthyroidal NIS may promote increased nitrosation in the gastric fluid, insufficient thiocyanate supply 

for myeloperoxidase, and gastrin imbalance. The function of NIS in the gastrointestinal tract was 

totally ignored in the EPA's decision not to regulate -- not a single GI tract specialist was consulted. 

Response: EPA agrees with the commenter that the Agency should regulate perchlorate. On 

August 19, 2009, EPA published a Federal Register notice requesting supplemental public 

comments on its preliminary determination not to regulate perchlorate in drinking water (Federal 

Register Vol. 74, No. 159, p. 41883). In this August 19, 2009 Federal Register notice, EPA requested 

comments on additional interpretation of data on the level of human health concern, perchlorate 

frequency of occurrence in drinking water, and the opportunity for health risk reduction through a 

national primary drinking water standard. EPA has considered and discusses in this Federal Register 

notice the results of current scientific literature on potential adverse biological effects, in the process 

of evaluating the adverse human health effects of perchlorate. The Agency analyzed the additional 

information, and EPA has determined that a national primary drinking water regulation for 

perchlorate would present a meaningful opportunity for health risk reduction for persons served by 

public water systems. 

Commenter Name: M. Peterson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0937 

EPA Comment ID: 20148 

EPA Comment Code: 2000 

Comment: Please review your decision regarding perchlorate regulation in water. The extremely 

high oxidizing potential of perchlorates produces radical species in water which have been 

determined as causing health problems - hydroxyl radicals, oxychlorides and the potential to form 

tri- and bi- halomethanes. The harsh effects of even low concentrations of highly oxidizing reactive 

species on organic tissues has not been fully studied and evaluated, yet their typical impacts have 

been determined to mutate and react to damage biological life forms. 

Response: Please see the response to comment ID 19898 under comment code 2000. 
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Commenter Name: Gail Charnley 

Commenter Organization: HealthRisk Strategies 

EPA Document ID: EPA-HQ-OW-2008-0692-1073 

EPA Comment ID: 20205 

EPA Comment Code: 2000 

Comment: RE: Docket ID No. EPA-HQ-OW-2008-0068 Comments on the US Environmental 

Protection Agency’s Preliminary Regulatory Determination on Perchlorate November 5, 2008 

Thank you for the opportunity to comment on the USEPA Office of Water’s Preliminary 

Regulatory Determination on Perchlorate. My comments address the relative sensitivities of the 

mammary and thyroid glands to the iodine-uptake- inhibiting effects of perchlorate and the 

implications that difference has for perchlorate’s reference dose (RfD). In short, scientific evidence 

indicates that the thyroid gland is 10 times more sensitive to the effects of perchlorate than the 

mammary gland; the 10X uncertainty factor currently incorporated into the RfD is thus protective 

not only of pregnant women but of nursing infants as well. 

EPA’s current RfD for perchlorate is, of course, based on perchlorate’s ability to inhibit the thyroid 

gland’s uptake of iodide by competing for the sodium (Na+)/iodide (I?) symporter (NIS), the 

protein responsible for transporting iodide into the thyroid gland for the purpose of synthesizing 

thyroid hormones. Because iodide uptake does not constitute an adverse effect itself, its choice as 

the basis for the RfD is health-protective. Insufficient iodide can result ultimately in changes in 

thyroid hormone levels, although normally such changes are compensated for. Insufficient thyroid 

hormone levels can impair normal fetal growth and development. Although studies have not 

specifically demonstrated adverse effects in children attributable to perchlorate,(1) the adverse 

effects of insufficient iodide are well known. 

Because the perchlorate RfD was based on a study performed using healthy adults, it incorporates a 

10X uncertainty factor to protect the most sensitive population the fetuses of pregnant women who 

might have hypothyroidism or iodide deficiency.(1) Iodide deficiency among pregnant women in the 

US is apparently not uncommon.(2) 

Recent concern about the adequacy of perchlorate’s RfD has focused on the results of studies 

demonstrating the presence of perchlorate in human milk at higher concentrations than in serum,(3) 

potentially posing a disproportionate risk to nursing infants. Although higher concentrations of milk 

perchlorate have not been associated with reduced milk iodide concentrations,(3) its presence in 

milk has led some to suggest that an additional uncertainty factor of 10 is needed to protect nursing 

infants.(4) An additional uncertainty factor of 10 is unnecessary, however, because the current RfD 

already protects nursing infants. 

The current RfD protects nursing infants because the potency of perchlorate as an iodide uptake 

inhibitor has been shown to be ten times weaker for the mammary gland than for the thyroid 

gland.(5,6) In other words, it would take ten times as much perchlorate exposure to inhibit 

mammary iodide uptake to the same extent as thyroid iodide uptake. There are two possible 

explanations for the difference: the mammary NIS is simply different and less easily inhibited 

compared to the thyroid NIS, or there are two mechanisms by which the mammary gland takes up 

iodide and the non-NIS mechanism compensates in part for the NIS when the latter is inhibited. 
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There is no evidence supporting or refuting the first explanation but there is evidence supporting the 

second.(6) 

The second mechanism by which the mammary gland obtains iodide is through the pendrin-iodide 

transporter.(7) When thyroid iodide uptake is inhibited, serum levels increase significantly, making 

more iodide available to the mammary gland (or placenta) and allowing the non-NIS mammary 

gland processes to help protect the newborn against inhibition.(8) 

Thus because the mammary gland is ten times less sensitive to iodide uptake inhibition by 

perchlorate compared to the thyroid gland due to the presence of an iodide uptake mechanism that 

is not only unaffected by perchlorate but compensates for its effects, the current perchlorate RfD of 

0.7 Âμg/kg/day is adequate to protect nursing newborns and an additional uncertainty factor is not 

needed. 

I would be happy to provide further information upon request. 

CITATIONS 

(1) National Academy of Sciences/National Research Council (2005). Health Implications of 

Perchlorate Ingestion. National Academy Press. Washington, DC 

(2) Caldwell KL, Jones R, Hollowell JG (2005). Urinary iodine concentration: United States. 

National Health And Nutrition Examination Survey 2001-2002. 

Thyroid 15:692-699 

(3) Pearce EN, Leung AM, Blount BC, Bazrafshan HR, He X, Pino S, Valentin- Blasini L, 

Braverman LE (2007). Breast milk iodine and perchlorate concentrations in lactating Boston-area 

women. Journal of Clinical Endocrinology and Metabolism 92:1673-1677; Kirk AB, Dyke JV, 

Martin CF, Dasgupta PK (2007). Temporal patterns in perchlorate, thiocyanate, and iodide excretion 

in human milk. Environmental Health Perspectives 115:182-186 

(4) Ginsberg GL, Hattis DB, Zoeller RT, Rice DC (2007). Evaluation of the U.S. EPA/OSWER 

Preliminary Remediation Goal (PRG) for perchlorate in groundwater: Focus on exposure to nursing 

infants. Environmental Health Perspectives 115:361-369 

(5) Tonacchera M, Pinchera A, Dimida A, Ferrarini E, Agretti P, Vitti P, Santini F, Crump K, Gibbs 

J (2004). Relative potencies and additivity of perchlorate,thiocyanate, nitrate, and iodide on the 

inhibition of radioactive iodide uptake by the human sodium iodide symporter. Thyroid 14:1012-

1019; De Groef B, Decallonne BR, Van der Geyten S, Darras VM, Bouillon R (2006). Perchlorate 

versus other environmental sodium/iodide symporter inhibitors: potential thyroid-related health 

effects. European Journal of Endocrinology 155:17-25 

(6) Potter GD, Tong W, Chaikoff IL (1959). The metabolism of 131I-labeled iodine, thyroxine, and 

triiodothyronine in the mammary gland of the lactating rat. Journal of Biological Chemistry 234:350-

355; Dasgupta PK, Kirk AB, Dyke JV, Ohira S-I (2008). Intake of iodine and perchlorate and 

excretion in human milk. Environmental Science & Technology 42:8115-8121 
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(7) Rillema JA, Hill MA (2003). Prolactin regulation of the pendrin-iodide transporter in the 

mammary gland. American Journal of Physiology, Endocrinology, & Metabolism 284:E25-E28 

(8) Clewell RA, Merrill EA, Gearhart JM, Robinson PJ, Sterner TR, Mattie DR, Clewell HJ (2007). 

Perchlorate and radioiodide kinetics across life stages in the human: Using PBPK models to predict 

dosimetry and thyroid inhibition and sensitive subpopulations based on developmental stage. 

Journal of Toxicology and Environmental Health, Part A 70:408-428 

Response: Please see the response to comment ID 28863 under comment code 2110 and response 

to comment code 2000. 

Commenter Name: Caroline Baier-Anderson, PhD 

Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20943 

EPA Comment Code: 2000 

Comment: Perchlorate Poses a Significant Risk to Human Health 

The principle mode of action of perchlorate has been well-characterized: perchlorate blocks iodide 

uptake in the thyroid by the sodium (Na+)-iodide (I-) symporter (NIS), an ion channel initially 

identified as the mechanisms of iodide uptake in the basal membrane of thyroid follicular cells 

(Stanbury and Wyngaarden 1952; Wyngaarden et al. 1952), which is necessary for thyroid hormone 

synthesis. The selectivity of perchlorate for the sodium-iodide symporter (NIS) is as much as 30-fold 

greater than for iodide (Tonacchera et al. 2004) suggesting that low concentrations of perchlorate 

can out-compete iodide for uptake into the thyroid. 

Significant inhibition of iodide uptake results in decreased production of iodine-rich thyroid 

hormones triiodothyronine (T3) and thyroxine (T4). Thyroid hormone production is regulated by a 

negative feedback system referred to as the hypothalamic-pituitary-thyroid axis. The thyroid 

produces T4 and T3; the pituitary gland produces thyroid stimulating hormone (TSH); and the 

hypothalamus produces thyrotrophic-releasing hormone (TRH). Cells in both the hypothalamus and 

pituitary gland respond to low levels of circulating T4 and T3; the hypothalamus stimulates the 

pituitary gland through TRH to produce TSH, which then prompts the thyroid to produce T4 and 

T3. Circulating plasma proteins can bind T4 and T3, serving as a reservoir. When thyroid production 

levels are low the output of TRH and TSH increase. 

Response: EPA agrees that perchlorate may pose an adverse risk to human health, as discussed in 

more detail in the preamble announcing the final determination. Also, see response to comment 

code 2000. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-2082 

EPA Comment ID: 21017 

EPA Comment Code: 2000 

Comment: P.O. Box 13222 Sacramento, CA95813 December 12, 2008 
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Dr. Melanie Marty, Chair Children’s Health Protection Advisory Committee Air Toxicology and 

Epidemiology Branch Office of Environmental Health Hazard Assessment 1515 Clay Street Suite 

1600 Oakland, CA 94612 

Dr. Marty: 

On behalf of the Perchlorate Study Group (PSG) I am writing in response to your November 3 

letter to US EPA Administrator Steven Johnson regarding the Agency’s preliminary determination 

on perchlorate. To be more specific, I’m writing in the hopes of addressing the various concerns you 

have raised and providing some additional perspective for your consideration. 

First, a little about the PSG. As manufacturers and users of perchlorate, the PSG is committed to 

ensuring the best available science is provided in public debate and applied in the subsequent setting 

of regulatory standards. The member companies of the PSG include Aerojet, American Pacific 

(AMPAC), Alliant Techsystems (ATK), and Tronox. 

By providing funding for scientific studies without interposition on the design, execution, or results 

for more than ten years, the PSG has worked cooperatively and effectively with the US 

Environmental Protection Agency (EPA) and other federal agencies, state governments, and water 

purveyors to: 

* increase scientific and medical understanding of perchlorate’s possible effects on human health; 

and, 

* assess the level of perchlorate in drinking water that is not expected to cause adverse effects even 

in the most sensitive population. 

We read your November 3 letter with great interest. In that letter, you raised several concerns with 

the scientific foundation of EPA’s preliminary determination and questioned whether EPA gave 

sufficient consideration to the health effects of perchlorate on sensitive populations other than 

pregnant women and their fetuses. 

As you are aware, EPA has been studying the health effects of perchlorate for more than 15 years 

releasing their first guidance document in 1992. Few chemicals have been the subject of such 

extensive research and so many peer- reviewed published studies. One of the unique scientific 

aspects of perchlorate is that we have a comprehensive understanding of how it affects the body. 

Due to its previous medical use and knowledge of the mechanism of action reduces uncertainty 

compared to most environmental chemicals. After several studies, draft risk assessments, guidance 

document revisions-- as well as an extensive and comprehensive review by the National Academy of 

Sciences (NAS), Agency for Toxic Substances and Disease Registry (ATSDR), and subsequent 

studies which have confirmed the NAS perchlorate panel’s conclusions-- EPA is well positioned to 

issue its determination. 

Response: EPA agrees that it has considered all relevant and best available science in making the 

final determination to regulate perchlorate. Also, see response to comment code 2000. 

Commenter Name: Michael Girard 
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Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-2082 

EPA Comment ID: 21019 

EPA Comment Code: 2000 

Comment: 2. Your letter asserts that EPA’s decision does not take into account that the developing 

brain is sensitive to small decreases in thyroid hormone levels and that neonates have diminished 

stores of thyroid hormone relative to adults. 

No references to support your position are provided in your letter. Thus it is difficult to assess the 

literature you may have used to support your statement. Nevertheless, there are some points to 

consider. First, thyroid hormones and pituitary hormones have normal and common temporal 

variability for a number of reasons (i.e., circadian rhythms, ambient temperature, etc.) Small changes 

in thyroid hormones are unlikely to cause long-term effects. To be adverse, changes due to chemical 

agents would have to be of a sustained, clinically significant magnitude over a period of time. 

Second, a very small number of scientists have argued that the infant has less storage of iodine or 

thyroid hormone than the adult which would make the infant more vulnerable than the pregnant 

woman or its fetus. However, the RfD is based on no inhibition of iodide uptake, a non adverse and 

fully reversible effect. The half-life of perchlorate is short (approximately 8 hours) and it does not 

bioaccumulate. Basing an RfD that cautiously prevents the first step in the biochemical pathway 

would prevent any downstream event from occurring. Thus any differences between adults and 

children are not likely to be a factor since the first step, inhibition of IUI, is prevented. Moreover, in 

its assessment of perchlorate and the identification of the most sensitive population, the NAS 

considered all the relevant literature, including those reporting the storage and half life of thyroidal 

parameters. With their review, the NAS made the assessment that in pregnant women, infants and 

children, and people who have a low iodide intake or pre-existing thyroid dysfunction, the dose 

required to cause a decrease in thyroid hormone production may be lower. However, a dose that 

does not inhibit thyroid iodide uptake will not affect thyroid function, even in subjects with an 

abnormal thyroid gland or a very low iodide intake. (NAS, 2005) 

Response: Please see the response to comment ID 21063 under comment code 4220 and response 

to comment ID 19898 under comment code 2000. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21055 

EPA Comment Code: 2000 

Comment: The EPA's National Center for Environmental Assessment (NCEA) prepared draft risk 

assessments for perchlorate in 1998 and 2002. The proposed reference doses (RfD) were 0.0009 

mg/kg-day in 1998 and 0.00003 mg/kg-day in 2002. Using EPA's conventional (or default) 

conversion factors, these reference doses translated to drinking water values of 32 and 1 ppb, 

respectively. Both reference doses proposed by EPA/NCEA were based on the results of animal 

studies. In 2002, EPA/NCEA interpreted these studies as showing adverse effects in the pups of 

rats exposed during pregnancy to a perchlorate dose as low as 0.01 mg/kg-day (U.S. EPA, 2002). 
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Public comments on the 2002 draft risk assessment raised serious concerns about the validity of 

using these animal studies for human health risk assessment (U.S. EPA, 2003). The EPA, NRCA, 

and the Departments of Energy and Defense jointly sponsored a review of the underlying science by 

the NRC. 

Response: EPA’s determination to regulate perchlorate is based upon the National Research 

Council’s 2005 (NRC, 2005) recommendation to use data from a human clinical study (Greer et al. 

2002) as a basis for the human health risk assessment, and as a basis for the current RfD. On August 

19, 2009, EPA published a FR Notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (FR Vol. 74, No. 159, p. 41883). In this 

August 19, 2009 FR Notice, EPA requested comments on additional interpretation of data on the 

level of human health concern, perchlorate frequency of occurrence in drinking water, and the 

opportunity for health risk reduction through a national primary drinking water standard. EPA has 

considered and discusses in the FR Notice the human health effects of perchlorate. The Agency 

analyzed the additional information received, and EPA has determined that perchlorate meets the 

criteria for regulating a contaminant in drinking water under Section 1412(b)(1)(A) of SDWA. See 

comment code 5000, 5100, 5200 and 5300 for further discussion of the criteria for a regulatory 

determination and EPA’s decision to regulate perchlorate. Greer MA, Goodman G, Pleus RC, Greer 

SE. Health effects assessment for environmental perchlorate contamination: the dose response for 

inhibition of thyroidal radioiodine uptake in humans. Environ Health Perspect. 2002 Sep;110(9):927-

37. Erratum in: Environ Health Perspect. 2005 Nov;113(11):A732. National Research Council 

(NRC). 2005. Health Implications of Perchlorate Ingestion. National Academies Press, Board on 

Environmental Studies and Toxicology, January, 2005, Washington, D.C. 276 p. 

Commenter Name: Kathy Curtis 

Commenter Organization: Alliance of Nurses for Healthy Environments (ANHE) 

EPA Document ID: EPA-HQ-OW-2009-0297-0651 

EPA Comment ID: 28542 

EPA Comment Code: 2000 

Comment: A 1 ppb or lower MCL is supported by the most recent comprehensive studies, and 

these should be central to EPA's analysis. The industry-supported Greer study, which serves as the 

basis for EPA's current reference dose consisted of a 14-day study of 37 healthy adults. In more 

recent years, Blount et al analyzed a nationally representative sample of 2299 U.S. residents, and they 

have documented anti-thyroid effects in a large population of women exposed to perchlorate at 

concentrations far lower than levels previously shown to have such effects. This study and 

subsequent data clearly justify promulgation of a more protective MCL. 

Response: On October 10, 2008, EPA published a FR Notice requesting public comments on its 

preliminary determination not to regulate perchlorate in drinking water (FR Vol. 73, No. 198, p. 

60266). EPA has considered and discusses in the FR Notice the results of the Greer et al. (2002), 

and Blount et al. (2006) studies, in the process of evaluating the adverse health effects of 

perchlorate. The Blount et al. (2006) study investigated adverse effects of perchlorate exposure with 

women with urinary iodine below 100 ug/L, and revealed adverse thyroid hormone effects in 

women whose urinary iodine was below 100 ug/L, which is suggestive of a partial study population 

iodine deficiency status. EPA published additional analyses of these and other studies in August 

2009. In this final determination, EPA evaluated the best available peer-reviewed science, and the 
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Agency has determined to regulate perchlorate in drinking water. An appropriate level for regulation 

has not yet been determined. 

Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell KL. Urinary perchlorate and thyroid 

hormone levels in adolescent and adult men and women living in the United States. Environ Health 

Perspect. 2006 Dec;114(12):1865-71. 

Greer MA, Goodman G, Pleus RC, Greer SE. Health effects assessment for environmental 

perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake in 

humans. Environ Health Perspect. 2002 Sep;110(9):927-37. Erratum in: Environ Health Perspect. 

2005 Nov;113(11):A732. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28877 

EPA Comment Code: 2000 

Comment: In the Notice EPA describes alternative interpretations of health and exposure data for 

perchlorate that may impact EPA's final regulatory determination for perchlorate. EPA seeks 

comments on these alternatives in three areas: 

* interpretation of physiologically-based pharmacokinetic (PBPK) modeling; 

* derivation of alternative health reference levels (HRLs) based on body weight and water 

consumption rates for sensitive life stages; and 

* use of data on perchlorate occurrence in drinking water. 

To provide context for these comments, several points regarding the availability of scientific data on 

perchlorate are important. First, substantial research and evaluation of the potential health effects of 

perchlorate have been conducted. The scientific literature represents more than five decades of 

scientific inquiry. Since EPA began evaluating perchlorate in the early 1990s, scientists from 

government, industry, and academia have made important contributions to reducing uncertainties 

about the risks of perchlorate to public health (see footnote 4). In response to EPA's request for 

comment on its preliminary determination, Intertox reviewed the existing data (Intertox, 

2008).[FN4: These comments were in response to the EPA FR notice Drinking Water: Preliminary 

Regulatory Determination on Perchlorate (U.S. EPA, 2008a).] Briefly, these data include: 

* the 2005 NRC assessment of perchlorate and update of key studies that have been added to the 

scientific literature; 

* at least twelve animal toxicological studies conducted between 1997 and 2002, all using EPA 

protocols, including pharmacokinetic, subchronic, developmental, and immunotoxicology studies, 

and a multigenerational reproductive study, conducted using a range of doses, and evaluated 

independently by EPA; 
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* several clinical and occupational exposure studies in humans and a number of epidemiologic and 

ecological studies between 1997 and 2002, some in occupational settings and some in populations 

exposed to perchlorate via the community drinking-water supply; and 

* additional studies conducted since 2002, adding to the scientific literature. 

Other agencies, e.g., the ATSDR (2008), have also conducted rigorous reviews of the scientific 

literature regarding the potential for adverse health effects from perchlorate exposure and have 

determined that doses equivalent to the current RfD are health protective. 

Second, a no observed effect level (NOEL) has been identified for perchlorate exposure in humans. 

At the lowest dose of Greer et al. (2002) (the basis of the perchlorate RfD), there was no statistical 

difference in iodide uptake inhibition (IUI), a nonadverse effect, for subjects before and after a dose 

of 0.007 mg/kg-d (245 ppb assuming default body weight and drinking water intake).[FN5: The 

actual variable measured in Greer et al. (2002) was radioactive iodide uptake or RAIU.] As the NRC 

(2005) states with emphasis, "Inhibition of iodide uptake by the thyroid clearly is not an adverse 

effect; however if it does not occur, there is no progression to adverse health effects." Use of a 

NOEL is more conservative than EPA's common approach using the no observable adverse effect 

level (NOAEL) or the lowest observable adverse effect level (LOAEL). 

Third, perchlorate is water soluble, has a half life in humans of approximately eight hours, and does 

not bioaccumulate. Because perchlorate has a short half life, some have questioned whether 

exposure to perchlorate might cause an acute effect. Toxicologically speaking, "acute" describes 

effects seen after one high dose or an exposure of less than 24 hours. No published study has 

demonstrated an effect after one exposure to perchlorate at environmental levels. The dose required 

for acute effects would require therapeutic levels; the medical literature reports that doses from 200 

mg to over 1 gram given on a daily basis (the equivalent of 100,000 to 500,000 ppb in drinking water 

using standard EPA default assumptions[FN6: 1g = 1,000 mg; Drinking Water Equivalent for 1,000 

mg perchlorate / 2 L of water per day = 500 mg/L or 500 ppm or 500,000 ppb; Drinking Water 

Equivalent for 200 mg would be 100 ppm or 100,000 ppb.]) are necessary to cause side effects (e.g., 

nausea and gastrointestinal upset at lower doses to aplastic anemia and agranulocytosis at daily doses 

of one gram or more) in 5 to 18 percent of study populations (NRC, 2005; Barzilai and Sheinfeld, 

1966). At exposures lasting several weeks to months (more commonly termed "subchronic"), the 

scientific literature does not demonstrate any evidence of adverse effect. Thyroxine (T4) has a half 

life of 6-8 days and must be sufficiently depleted for developmental effects to occur. A single 

perchlorate dose in excess of 1 gram per day would most likely cause some frank toxicity, but based 

on the science to date, will not decrease serum thyroid hormone levels without daily exposure for 

weeks. 

Fourth, the NRC's recommendation to base the RfD on a NOEL was conservative and health 

protective, as this dose is lower than any dose at which adverse effects may occur. To derive the 

RfD, the NOEL was divided by an uncertainty factor (UF) of 10 to account for the most sensitive 

individuals in a population, the hypothyroid or iodine-deficient pregnant women and their 

developing fetuses. The NRC committee stated that using a NOEL as the point of departure (POD) 

is a more conservative and health protective approach than EPA's customary approach of using the 

adverse effect (NRC, 2005). For example, the use of the threshold for IUI as a POD is more 

conservative and health protective than using changes in thyroid hormones (also a precursor to 

possible adverse effects) or an adverse effect such as hypothyroidism. 
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Perchlorate's reversible inhibition of the NIS is documented in many experiments, both in vivo and 

in vitro. This interaction exhibits the standard sigmoidal dose-response curve in toxicology and 

pharmacology-as dose increases, so does the response. There is no scientific evidence to suggest that 

low doses of perchlorate will cause any other effect. Perchlorate competitively inhibits iodide uptake; 

it neither mimics a hormone nor directly stimulates a response. 

Response: See response to comment code 2000. 
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EPA Comment Code: 2100 NAS (NRC) review of perchlorate health effects 

and reference dose 

Response to Comment Code 2100: On October 10, 2008, EPA published a Federal Register 

notice presenting the Agency’s preliminary regulatory determination for perchlorate and supporting 

rational for this determination, in accordance with the Safe Drinking Water Act (SDWA) (Federal 

Register Vol. 73, No. 198, p. 60262). In this October 10, 2008 Federal Register notice, EPA 

determined that a national primary drinking water regulation (NPDWR) for perchlorate would not 

present a meaningful opportunity for health risk reduction for persons served by public water 

systems. In 2003, the National Research Council (NRC) of the National Academy of Sciences (NAS) 

was asked by EPA to assess the current state of the sciences regarding potential adverse effects of 

perchlorate exposure in human and animals, and to determine whether EPA’s prior perchlorate risk 

assessment findings were consistent with current scientific evidence. In a NRC 2005 review of the 

state of the sciences regarding potential perchlorate adverse health effects and mode-of-action 

(“Health Implications of Perchlorate Ingestion”, NRC 2005), the NRC recommended that data 

from the Greer et al. (2002) human clinical study be used as the basis for deriving a perchlorate 

reference dose (RfD)(NRC 2005). From this Greer et al. (2002) human clinical study, the statistical 

no observed effect level (NOEL) for the perchlorate-induced inhibition of thyroid iodide uptake 

was determined to be 7.0 ug/kg, which corresponded to an iodide uptake inhibition of 1.8 %. The 

NRC concluded that the most health protective and scientifically valid approach to deriving a 

reference dose for perchlorate was to base the perchlorate RfD on the inhibition of iodide uptake by 

the thyroid, and that iodide uptake inhibition, though not an adverse effect per se, is the most 

appropriate precursor event, and would precede any more severe adverse health effects of 

perchlorate exposure in humans. The NRC recommended basing the RfD on a precursor to an 

adverse effect rather than an adverse effect per se. The precursor event precedes a downstream 

adverse effect in the dose response continuum. In this case, NRC used prevention of iodide uptake 

inhibition, a precursor to adverse thyroid effects, to establish a level at which no adverse effects 

would be anticipated in exposed populations. This approach is consistent with the Agency’s policy 

on the use of precursor events when appropriate in establishing the critical effect upon which an 

RfD is based (U.S. EPA, 2002). The NRC recommended that EPA apply an uncertainty factor of 10 

to this NOEL of 7.0 ug/kg for the perchlorate-induced inhibition of thyroid iodide uptake, to 

account for differences in sensitivity between healthy adults and the most sensitive sub-population, 

consisting of fetuses of pregnant women who might have hypothyroidism or iodide deficiency. The 

NRC viewed the recommended uncertainty factor of 10 as conservative and protective of health, 

given that the NOEL is based on a non-adverse effect (iodide uptake inhibition) which precedes the 

adverse effect in a continuum of possible adverse biological effects of perchlorate exposure. NRC 

recommended that using a non-adverse effect that is upstream of the adverse effect represents a 

more conservative, health-protective approach to the risk assessment for perchlorate, noting that the 

purpose of the 10-fold uncertainty factor is to protect sensitive subpopulations in the face of 

uncertainty regarding their relative sensitivity to perchlorate exposure. EPA has adopted the NRC’s 

recommendations in its “Integrated Risk Information System” (IRIS) (USEPA 2005), resulting in an 

RfD of 0.7 ug/kg/day, which was derived by applying a 10-fold (10x) uncertainty factor to the 

NOEL of 7.0 ug/kg/day. 

EPA believes the NRC appropriately based the RfD on iodide uptake inhibition to the thyroid, for 

the reasons discussed in its report. EPA notes that the data underlying the definition of iodide 

uptake inhibition as a precursor effect and the relationship of iodide uptake inhibition to the 
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continuum of adverse outcomes reflects an understanding of effects in adults; it may not reflect the 

relationship of the precursor event to adverse outcomes in neonates and infants, who may not have 

iodide stores sufficient to offset the effects of reduced iodide uptake. The less resilient neonatal and 

infant system makes the exposure gap between a precursor event (iodide uptake inhibition due to 

perchlorate) and reduced T3/T4 levels likely to be narrower than for adults, and in fact, the 

distinction between the two may be blurred for the very young (Greer et al., 2002; Savin et al., 2003; 

van den Hove et al., 1999). The NRC noted that, “[T]he minimal prolonged decrease in thyroid 

hormone production that would be associated with adverse health effects is not known; any 

decrease is potentially more likely to have adverse effects in sensitive populations (people with 

thyroid disorders, pregnant women, fetuses, and infants) but data are not available to determine the 

magnitude of the decrease needed to cause adverse effects in those populations.” 

Individual Comments 

Commenter Name: Melanie A. Marty, Ph.D. 

Commenter Organization: Children's Health Protection Advisory Committee 

EPA Document ID: EPA-HQ-OW-2008-0692-0962 

EPA Comment ID: 20418 

EPA Comment Code: 2100 

Comment: We note that the RfD itself is uncertain and is not necessarily a health protective 

benchmark. It is based upon a limited clinical study of short duration and small sample size not 

representative of the variability in the human population (Greer, et al., 2002). When a larger 

epidemiologic study was conducted by CDC, significant correlations were found between increasing 

perchlorate exposure and decreasing thyroid hormone levels in the subpopulation of women with 

low iodide intake, which the CDC NHANES data show constitutes 31% of all women (Blount, et al 

2006). The exposure levels associated with anti- thyroid effects in these women were below the 

perchlorate RfD. These findings cast doubt on the protectiveness of the RfD, and make it especially 

important that no group exceed this health benchmark. 

Response: See response to comment ID 28936 under comment code 2100. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association 

EPA Document ID: EPA-HQ-OW-2008-0692-1424 

EPA Comment ID: 20439 

EPA Comment Code: 2100 

Comment: Exposure 

In addition to occurrence, the evaluation criteria in the SDWA also consider whether contamination 

is occurring at levels "of public health" concern and whether regulation of the contaminant would 

meaningfully reduce potential health risks. AWWA would like to acknowledge and compliment the 

National Research Council for the extensive assessment of risk that resulted in setting the oral 

Reference Dose (RfD) at 7x10-4 mg/kg-day. In consideration of the SDWA criteria, it should be 

emphasized that the RfD represents a No Observed Effect Level (NOEL) versus the more 

traditional No ObservedAdverse Effect Level (NOAEL). As discussed by Crawford-Brown et.al. 
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(2006) and in the proposed decision, a NOAEL is by definition equal to or higher than a NOEL 

wherethe effect used to establish the NOEL is a precursor to the adverse effect of interest in 

establishing a NOAEL. The NRC's use of a precursor to an adverse effect (iodine uptake inhibition) 

in establishing a threshold for exposure represents a "more conservative, health-protective 

approach". This assures the protection of the sensitive subpopulation (iodide-deficient pregnant 

women and their fetuses) and mitigates the need for additional uncertainty factors to be applied. 

Response: EPA does not agree that use of precursor effect alters the need for uncertainty factors. 

Uncertainty factors are applied to respond to specific aspects of uncertainty in some aspect of the 

health assessment, regardless of the nature of the endpoint used. Examples include intraspecies or 

interspecies variability, data gaps, or discrepancies in time course of the study compared to the 

anticipated effect/exposure profile in the public. Also, see response to comment code 2100. 

Commenter Name: Gregg Grunenfelder 

Commenter Organization: Washington State Department of Health; and Oregon Department of 

Human Services 

EPA Document ID: EPA-HQ-OW-2008-0692-1529 

EPA Comment ID: 20454 

EPA Comment Code: 2100 

Comment: Perchlorate interferes with iodide uptake and affects the release of thyroid hormones. 

Appropriate levels of thyroid hormones are critical to the development of the brain and other 

organs, making the fetus and newborn infant particularly sensitive to perchlorate toxicity. Maternal 

exposure to elevated levels of perchlorate has been linked to mild, in some cases severe and 

irreversible, neurological outcomes in infants. Perchlorate is but one more contaminant along with 

mercury, PCBs, PBDEs, and lead that adversely impact the developing brain. 

Washington Department of Health and Oregon Department of Human Services, Public Health 

Division believe that the 10-fold uncertainty factor used by EPA to derive a Reference Dose (RfD), 

and its subsequent use to formulate a health based drinking water level, is insufficient. 

We believe that due to the data gaps in the limited studies available for perchlorate that a higher 

uncertainty factor is warranted. Back in 2002, EPA more appropriately utilized a higher uncertainty 

factor in the agency’s assessment of perchlorate, as did the state of Massachusetts in their in-depth 

risk assessment of perchlorate. Exposure estimates based on a more protective RfD indicate that, at 

any one time, as many as 210,000 pregnant women in the US are exposed to unsafe levels of 

perchlorate. This view of risk could well influence the conclusion as to whether or not a national 

regulation of percholorate in drinking water presents a meaningful opportunity to protect public 

health. 

As state regulators, we strive to evaluate chemical hazards in a consistent manner. If EPA had used 

its standard risk assessment methodology, their findings of the hazards of perchlorate in drinking 

water would have been significantly different. We recommend that EPA reconsider its evaluation 

since there is no obvious scientific reason for using the different methodology which led to this 

preliminary determination. 

We support the scientific approach reflected in the enclosed information prepared by the 

Washington Department of Health, and ask that EPA carefully consider it as your agency 
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determines the appropriate next step. Further, if we can provide any further information regarding 

this important public health issue, please contact us, Gregg Grunenfelder, Washington State 

Department of Health, (360.236.3050) or Gail Shibley, Oregon State Department of Human Health 

Services (971.673.0400). 

Sincerely, 

Gregg Grunenfelder, Assistant Secretary Washington State Department of Health Division of 

Environmental Health 

Gail R. Shibley, Administrator Oregon State Department of Human Services Office of 

Environmental Public Health 

Response: Please see response to comment ID 28818 under comment code 2100. 

Commenter Name: Gregg Grunenfelder 

Commenter Organization: Washington State Department of Health; and Oregon Department of 

Human Services 

EPA Document ID: EPA-HQ-OW-2008-0692-1529 

EPA Comment ID: 20455 

EPA Comment Code: 2100 

Comment: Enclosure 

November 10, 2008 Docket ID No. EPA-HQ-OW-2008-0692 Comments on EPA’s Preliminary 

Regulatory Determination for Perchlorate Prepared by Washington State Department of Health 

On October 10, 2008, the US Environmental Protection Agency (EPA) placed an action notice on 

the Federal Register [FN1: EPA 2008. Fact Sheet: Preliminary Regulatory Determination for 

Perchlorate. Office of Water. United States Environmental Protection Agency. EPA 815-F-08-009. 

October 2008.],[FN2: Federal Register: October 10, 2008 (Volume 73, Number 198). Notices. Page 

60262-60282. From the Federal Register Online via GPO Access [wais.access.gpo.gov] 

[DOCOD:fr10oc08-66].] relating to preliminary regulatory determination for perchlorate in 

accordance with the federal Safe Drinking Water Act. The agency determined that a national primary 

drinking water regulation for perchlorate would not present "a meaningful opportunity for health 

risk reduction for persons served by public water systems." EPA will make a final regulatory 

determination for perchlorate after considering public comments and information provided during 

the 30-day comment period ending November 10, 2008. EPA intends on publishing its final 

regulatory determination in December 2008 to provide state and local public health officials with 

technical information that can be used to address local contamination. 

Perchlorate (ClO4) is a naturally occurring inorganic compound that can also be manufactured. 

Ammonium perchlorate (NH4ClO4), is a salt used as an oxidizer in rocket propellants and 

fireworks. It has also been found in certain fertilizers, and was used in the past as a medicine to treat 

hyperthyroidism (overactive thyroid) in humans. Perchlorate salts are ionic and dissociate completely 

when dissolved in water. The soluble anion ClO4 has been found in groundwater in many states 

where testing has occurred. To date, it is not clear to what extent perchlorate is found in 

groundwater across the United States, because it has not been widely studied. In the northwest, low 
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levels of perchlorate have been found in groundwater in some tested areas of eastern Washington 

and Oregon. 

Perchlorate interferes with the thyroid’s ability to take in iodide. The thyroid needs iodide to 

produce certain hormones that are necessary for numerous body functions. If the thyroid is unable 

to produce enough of these hormones, a condition known as hypothyroidism (underactive thyroid 

disease) may result. Thus, perchlorate exposure has the potential to result in hypothyroidism. 

All people are susceptible to perchlorate’s effects on the thyroid (decreased iodide uptake), but 

pregnant women, infants, children, and people with low iodide intake in the diet, or pre-existing 

thyroid problems may be more susceptible. Hypothyroidism, if untreated, can lead to numerous 

health effects including, fatigue, muscle aches, unexplained weight-gain, depression, and many other 

symptoms. Moreover, hypothyroidism in pregnant women (developing fetuses), infants, and 

children can lead to impaired mental and physical development. Maternal exposure to elevated levels 

of perchlorate has been linked to mild, and in some cases severe and irreversible neurological 

outcomes in infants. Similar adverse outcomes to the developing fetus have been documented with 

exposure to mercury, PCBs, PBDEs, and lead. 

In the absence of federal regulatory standards on perchlorate, several states have developed 

Reference Doses (RfD) or safe doses that are used to derive safe drinking water guidance or 

standards. Most notably are recent efforts by EPA [FN3: EPA 2002. Perchlorate environmental 

contamination: toxicological review and risk characterization. External Review Draft. United States 

Environmental Protection Agency. Office of Research and Development. NCEA-1-0503. January 

16, 2002.], California [FN4: Ting D, Howd RA, Fan AM, and Alexeeff GV. 2006. Development of a 

Health-Protective Drinking Water Level for Perchlorate. Environmental Health Perspectives (114)6: 

881-86.],[FN5: California Environmental Protection Agency. 2004. Office of Environmental Health 

Hazard Assessement. Public Health Goals for Chemicals in Drinking Water: Perchlorate. March 

2004.], New Jersey [FN6: New Jersey Department of Environmental Protection 2005. New Jersey 

Drinking Water Quality Institute. Maximum Contaminant Level Recommendation for Perchlorate. 

October 7, 2005.], Massachusetts [FN7: Massachusetts Department of Environmental Protection. 

2006. Office of Research and Standards. Update to "Perchlorate Toxicological Profile and Health 

Assessment". March 2006.], and the National Research Council of the National Academy of Science 

(NAS) [FN8: National Academy of Sciences. 2005. Health Implication of Perchlorate Ingestion. 

National Academies Press. Washington D.C. Available at URL: 

http://www.nap.edu/catalog.php?record_id=11202]. 

EPA conducted the initial draft toxicological review of perchlorate in 2002, resulting in a proposed 

RfD of 0.00003 mg/kg/day based primarily on studies that identified neurodevelopmental deficits in 

rat pups [FN9: Argus 2001. Hormone, thyroid, and neurohistological effects of oral (drinking water) 

exposure to ammonium perchlorate in pregnant and lactating rats and in fetuses and nursing pups 

exposed to ammonium perchlorate during gestation or via maternal milk. Argus Research 

Laboratories, Inc. Horsham, PA. Protocol no. ARGUS 1416-003. Cited in EPA 2002.]. These 

deficits were linked to maternal exposure to perchlorate. Subsequent to this assessment, California, 

New Jersey, the NAS, and Massachusetts reviewed the health implications of perchlorate, and each 

proposed an alternative reference dose of 0.0004, 0.0007, 0.0007, and 0.00003 mg/kg/day, 

respectively. This is based primarily on a study on humans conducted by Greer et al. published in 

2002. A summary of perchlorate reference doses developed by the various agencies is presented in 

Table 1. 
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[Table 1. Comparison of Perchlorate Reference Doses (RfD) Developed by Other Agencies - see 

PDF Docket ID EPA-HQ-OW-2008-0692-1259] 

In the Greer et al. [FN10: Greer MA, Goodman, F, Pleus RC, and Greer SE. 2002. Health Effects 

Assessment for Environmental Perchlorate Contamination: The Dose Response for Inhibition for 

Thyroid Radioiodine Uptake in Humans. Environmental Health Perspectives (110)9: 927-37.] study 

cited by four of the five agencies, 37 human subjects were split into four exposure groups and 

administered oral doses of perchlorate at 0.007 (7 subjects), 0.02 (10 subjects), 0.1 (10 subjects), and 

0.5 (10 subjects) mg/kg/day. Significant decreases in iodide uptake were found in the three highest 

exposure groups. Iodide uptake was not significantly reduced in the lowest exposed group, but four 

of the seven subjects in this group experienced inhibited iodide uptake. The RfD proposed by NAS 

was accepted by EPA and added to its integrated risk information system (IRIS) in 2005. 

Much debate was generated following EPA’s posting of the RfD in IRIS, most notably in 

commentary submitted to the journal Environmental Health Perspectives by Ginsberg and Rice 

[FN11: Ginsberg G and Rice D. 2005. The NAS Perchlorate Review: Questions Remain about the 

Perchlorate RfD. Environmental Health Perspectives (115)3: 361-69.]. The authors argued that the 

RfD was not adequately protective of human health for the following reasons: 

1. The NAS report described the level of lowest exposure from Greer et al. as a no observed effect 

level (NOEL). However, there was actually an effect at that level although not statistically significant 

largely due to small size of study population (four of seven subjects showed a slight decrease in 

iodide uptake). 

2. Reduced iodide uptake was not considered an adverse effect. However, it is a precursor to an 

adverse effect (hypothyroidism). Therefore, additional safety factors are necessary when 

extrapolating from the point of departure to the RfD. 

3. Consideration of data uncertainty was insufficient because the Greer, et al. study reflected only a 

14-day exposure to healthy adults and no additional safety factors were considered to protect 

sensitive subpopulations. For example, the potential for greater toxicity to breastfeeding newborns 

was not considered. 

Response: EPA believes that the RfD recommended by the NAS remains appropriate, as discussed 

in the other responses to comments in this section (comment code 2100); however, EPA will be 

continue to evaluate scientific studies of perchlorate health effects as the Agency develops the 

National Primary Drinking Water Regulation for perchlorate. 

Commenter Name: Gregg Grunenfelder 

Commenter Organization: Washington State Department of Health; and Oregon Department of 

Human Services 

EPA Document ID: EPA-HQ-OW-2008-0692-1529 

EPA Comment ID: 20458 

EPA Comment Code: 2100 

Comment: The Department of Health’s Conclusions: 
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There is consensus among agencies that the Greer et al. study is appropriate for deriving the RfD, 

but there is not consensus with regard to developing drinking water maximum contaminant levels 

(MCLs) or action levels. One of the key differences results from how the point of departure is 

viewed [i.e., No observed effect level (NOEL) or lowest observed adverse effect level (LOAEL)], or 

whether a benchmark dose should be used to derive the RfD. Defining the point of departure as a 

NOEL or LOAEL has implications when it comes to applying appropriate safety factors to the 

point of departure to derive the RfD. 

Based on a review of existing literature, the Department of Health has identified the following 

concerns with EPA’s perchlorate action level: 

* EPA’s RfD, which is the basis for the health reference level, may not be protective of public health 

with a reasonable margin of safety. 

Response: Please see response to comment code 2100 for a discussion of the RfD. See Response to 

comment code 5220 for a discussion of alternative Health Reference Levels. EPA will continue to 

refine its analyses for purposes of proposing an MCL and MCLG. EPA plans to seek comment on 

the proposed national drinking water regulation pursuant to the requirements of the Safe Drinking 

Water Act. 

Commenter Name: Carol Bigelow 

Commenter Organization: University of Massachusetts 

EPA Document ID: EPA-HQ-OW-2008-0692-1427 

EPA Comment ID: 20630 

EPA Comment Code: 2100 

Comment: We also found critical errors in the selection, design and interpretation of the studies 

that were included in docket ID No. EPA-HQ-OW-2008-0692. The irrelevant studies should be 

dropped from the docket, the flawed interpretations of the remaining studies should be corrected, 

and the conclusions drawn revised. 

Several studies reported in docket ID No. EPA-HQ-OW-2008-0692 are either inappropriate for 

inclusion, or erred in their design or interpretation. Most significant in this regard is the population 

that was emphasized by the EPA in citing the NAS report of 2005 (NRC, 2005): pregnant adults. 

EPA provided no scientific justification for this emphasis. Moreover, the emphasis on the pregnant 

adult illustrates the mistake of public health recommendations by persons who are not at significant 

risk. As we’ve noted above: "the adult thyroid system appears capable of significant compensation 

for low thyroid hormone levels, and the consequences of low thyroid hormone are likely to be 

reversible." 

Response: EPA respectfully disagrees with the commenter. It is also noted that the commenter 

does not specify which studies she is critical of. In a NRC 2005 review of the state of the sciences 

regarding potential perchlorate adverse health effects and mode-of-action (“Health Implications of 

Perchlorate Ingestion”, NRC (2005)), the NRC recommended that data from the Greer et al. (2002) 

human clinical study be used as the basis for deriving a perchlorate reference dose (RfD) (NRC 

2005). From this Greer et al. (2002) human clinical study, the statistical no observed effect level 

(NOEL) for the perchlorate-induced inhibition of thyroid iodide uptake was determined to be 7.0 

ug/kg, which corresponded to an iodide uptake inhibition of 1.8%. The NRC concluded that the 
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most health protective and scientifically valid approach to deriving a reference dose for perchlorate 

was to base the perchlorate RfD on the inhibition of iodide uptake by the thyroid, and that iodide 

uptake inhibition, though not an adverse effect per se, is the most appropriate precursor event, and 

would precede any more severe adverse health effects of perchlorate exposure in humans. The NRC 

recommended basing the RfD on a precursor to an adverse effect rather than an adverse effect per 

se. The precursor event precedes a downstream adverse effect in the dose response continuum. In 

this case, NRC used prevention of iodide uptake inhibition, a precursor to adverse thyroid effects, to 

establish a level at which no adverse effects would be anticipated in exposed populations. This 

approach is consistent with the Agency’s policy on the use of precursor events when appropriate in 

establishing the critical effect upon which an RfD is based (U.S. EPA, 2002). The NRC 

recommended that EPA apply an uncertainty factor of 10 to this NOEL of 7.0 ug/kg for the 

perchlorate-induced inhibition of thyroid iodide uptake, to account for differences in sensitivity 

between healthy adults and the most sensitive sub-population, consisting of fetuses of pregnant 

women who might have hypothyroidism or iodide deficiency. Iodide uptake inhibition has been 

identified in the literature as an area of concern in connection with increasing the risk of 

neurodevelopmental impairment in fetuses of high-risk mothers. The NRC viewed the 

recommended uncertainty factor of 10 as conservative and protective of health, given that the 

NOEL is based on a non-adverse effect (iodide uptake inhibition) which precedes the adverse effect 

in a continuum of possible adverse biological effects of perchlorate exposure. NRC recommended 

that using a non-adverse effect that is upstream of the adverse effect represents a more conservative, 

health-protective approach to the risk assessment for perchlorate, noting that the purpose of the 10-

fold uncertainty factor is to protect sensitive subpopulations in the face of uncertainty regarding 

their relative sensitivity to perchlorate exposure. EPA has adopted the NRC’s recommendations in 

its “Integrated Risk Information System” (IRIS) (USEPA, 2005), resulting in an RfD of 0.7 

ug/kg/day, which was derived by applying a 10-fold (10x) uncertainty factor to the NOEL of 7.0 

ug/kg/day. Greer MA, Goodman G, Pleus RC, Greer SE. Health effects assessment for 

environmental perchlorate contamination: the dose response for inhibition of thyroidal radioiodine 

uptake in humans. Environ Health Perspect. 2002 Sep;110(9):927-37. National Research Council 

(NRC). 2005. Health Implications of Perchlorate Ingestion. National Academies Press, Board on 

Environmental Studies and Toxicology, January, 2005, Washington, D.C. 276pp. USEPA. 2002. A 

review of the reference dose and reference concentration processes. Risk Assessment Forum, 

Washington, DC; EPA/630/P–02/0002F. USEPA. 2005. ‘‘Integrated Risk Information System 

(IRIS), Perchlorate and Perchlorate Salts.’’ February 2005. 

Commenter Name: Michael Dourson 

Commenter Organization: Toxicology Excellence for Risk Assessment 

EPA Document ID: EPA-HQ-OW-2008-0692-1562 

EPA Comment ID: 20641 

EPA Comment Code: 2100 

Comment: Our primary concern is related to the RfD EPA used to estimate Health Reference 

Level. Our comments follow three lines of evaluation: 

1. Critically important data on pregnant women and their offspring have become available since the 

time of the development of the EPA RfD in 2005 (EPA, 2008), which necessitate a reconsideration 

of the existing value. This reconsideration is consistent with recommendations of the NAS (2005) 

on page 69 of its report. 
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2. The excellent relative source contribution evaluation of EPA, based on well supported and clearly 

described work of the FDA, necessitates a rethinking of the EPA’s RfD, since the subjects in Greer 

et al. (2002) on which it was based undoubtedly had unmeasured perchlorate in their food. 

3. The 2005 NAS "RfD" does not follow the existing EPA RfD method. 

All three of these arguments are more fully discussed below. We also offer a commentary on the 

Blount et al. (2007) that may have some bearing on this federal action (Attachment A). Note, while a 

reanalysis of the RfD will not have an effect on the regulatory conclusion discussed in this Federal 

Register notice, it will have an effect on the Health Advisory that EPA derives, which will be used 

by States for their regulation of perchlorate. 

Response: See response to comment ID 20957 under comment code 2100 for a discussion of 

adjusting the Greer study to account for perchlorate which may have been in subjects’ food. 

EPA supports the review and evaluation of additional new data regarding the health effects of 

perchlorate. However EPA respectfully disagrees with the commenter regarding the NRC (2005) 

recommendations for the RfD, as discussed below. EPA will continue to evaluate scientific studies 

of perchlorate health effects as part of the perchlorate rulemaking 

The EPA “Integrated Risk Information System” (IRIS) employs EPA’s standard risk assessment 

methodology. The RfD, which is derived from the NOEL, is an estimate (with uncertainty spanning 

perhaps an order of magnitude) of a daily oral exposure to the human population that is likely to be 

without an appreciable risk of deleterious effects during a lifetime. The RfD, based on the 

assumption that thresholds exist for certain toxic effects of chemicals, represents the drinking water 

perchlorate exposure plus an incremental additional exposure of perchlorate from either water or 

food which could trigger iodine uptake inhibition, with a 10X safety factor applied. The NRC 

recommended that data from the Greer et al. (2002) human clinical study be used as the basis for 

deriving a perchlorate reference dose (RfD) (NRC 2005), and also noted that the results of this study 

were supported by those of other human studies. From this Greer et al. (2002) human clinical study, 

the statistical no observed effect level (NOEL) for the perchlorate-induced inhibition of thyroid 

iodide uptake was determined to be 7.0 ug/kg (a corresponding iodide uptake inhibition of 1.8%). 

The NRC concluded that the most health protective and scientifically valid approach was to base the 

perchlorate RfD on the precursor event of inhibition of iodide uptake by the thyroid. This approach 

is consistent with the Agency’s policy on the use of precursor events when appropriate in 

establishing the critical effect upon which an RfD is based (U.S. EPA, 2002). The NRC 

recommended that EPA apply an uncertainty factor of 10 to this NOEL of 7.0 ug/kg to account for 

differences in sensitivity between healthy adults and the most sensitive sub-population (fetuses of 

pregnant women who might have hypothyroidism or iodide deficiency). Iodide uptake inhibition 

due to perchlorate exposure has been identified as an area of concern in connection with increasing 

the risk of neurodevelopmental impairment in fetuses of high-risk mothers. The NRC viewed the 

recommended uncertainty factor of 10 as conservative and protective of health. NRC recommended 

that using a non-adverse effect that is upstream of the adverse effect represents a more conservative, 

health-protective approach to the risk assessment for perchlorate, noting that the purpose of the 10-

fold uncertainty factor is to protect sensitive subpopulations in the face of uncertainty regarding 

their relative sensitivity to perchlorate exposure. EPA has adopted the NRC’s recommendations in 

its “Integrated Risk Information System” (USEPA, 2005), resulting in an RfD of 0.7 ug/kg/day, 

which was derived by applying a 10-fold uncertainty factor to the NOEL of 7.0 ug/kg/day. EPA 
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used the best available peer-reviewed science, and the Agency has determined to regulate perchlorate 

in drinking water. 

Greer MA, Goodman G, Pleus RC, Greer SE. Environ Health Perspect. 2002 Sep;110(9):927-37. 

National Research Council (NRC). 2005. Health Implications of Perchlorate Ingestion. National 

Academies Press, Board on Environmental Studies and Toxicology, January, 2005, Washington, 

D.C. 276pp. USEPA. 2002. A review of the reference dose and reference concentration processes. 

Risk Assessment Forum, Washington, DC; EPA/630/P–02/0002F. USEPA. 2005. "Integrated Risk 

Information System (IRIS), Perchlorate and Perchlorate Salts." February 2005. 

Commenter Name: Michael Dourson 

Commenter Organization: Toxicology Excellence for Risk Assessment 

EPA Document ID: EPA-HQ-OW-2008-0692-1562 

EPA Comment ID: 20642 

EPA Comment Code: 2100 

Comment: Availability of New Data 

Critically important data on pregnant women and their offspring have become available since the 

time of the development of the 2005 EPA’s Reference Dose (RfD) (EPA, 2008), which necessitate a 

reconsideration of the existing value. 

For example, although the NAS recommended that the Greer et al (2002) be used as the basis of the 

RfD, the NAS also recognized that new, useful data were under development: 

"On the basis of the iodide-inhibition analyses, the additional comparisons, and a review of 

information on urinary iodide excretion, the committee concluded that the data from Chile could be 

considered in the evaluation of the U.S. experience with perchlorate in drinking water." (NAS, 2005, 

page 69) 

The data to which NAS referred was published prior to the NAS report as Crump et al. (2000), and 

after the NAS report as Tellez et al. (2005), the abstract of which reads: 

"We have conducted a longitudinal epidemiologic study among pregnant women from three cities in 

northern Chile: Taltal with 114 ug/L, Chañaral with 6 ug/L, and Antofagasta with 0.5 ug/L 

perchlorate in the public drinking water. We tested the hypothesis that long-term exposure to 

perchlorate at these levels may cause a situation analogous to iodine deficiency, thus causing 

increases in thyrotropin (TSH) and thyroglobulin (Tg) levels and decreased levels of free thyroxine 

(FT4), in either the mother during the early stages of gestation or the neonate at birth, or in the fetus 

cause growth retardation. We found no increases in Tg or TSH and no decreases in FT4 among 

either the women during early pregnancy (16.1 +/- 4.1 weeks), late pregnancy (32.4 +/- 3.0 weeks), 

or the neonates at birth related to perchlorate in drinking water. Neonatal birth weight, length, and 

head circumference were not different among the three cities and were consistent with current U.S. 

norms. Therefore, perchlorate in drinking water at 114 ug/L did not cause changes in neonatal 

thyroid function or fetal growth retardation. Median urinary iodine among the entire cohort was 269 

ug/L, intermediate between that of pregnant women in the United States at National Health and 

Nutrition Examination Survey (NHANES) I and at NHANES III and consistent with current 

World Health Organization (WHO) recommendations. Median breast milk iodine was not decreased 
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in the cities with detectable perchlorate. Analysis of maternal urinary perchlorate excretion indicates 

an additional dietary source of perchlorate." (Tellez et al., 2005) 

In addition, EPA has discussed other data relevant to deriving an updated RfD in this Federal 

Register notice, including Amitai et al., 2007, Blount et al., 2006b (see a separate discussion of 

Blount in Attachment A), and the studies discussing PBPK models (Merrill et al., 2005; Clewell et 

al., 2007). 

Contribution of Perchlorate in Food to Total Exposure 

As EPA discussed in this Federal Register notice, the US population is being exposed to perchlorate 

through both food and water. Based on EPA’s excellent relative source contribution evaluation 

(Table 6), the dose of perchlorate from food could range from 0.075 ug/kg-day (median dose) to 

0.167 ug/kg-day (90th percentile dose) and account for 24% of total perchlorate exposure for the 

general population. 

This information may necessitate a rethinking of the 2005 RfD based on Greer et al. (2002). Since 

these investigators did not measure perchlorate in the food of the human subjects, it is likely the 

total perchlorate dose received by the subjects was higher than the drinking water dose of 0.007 

mg/kg-day that was used as the point of departure for the RfD. This same consideration might also 

be appropriate for RfDs based on other human studies. 

The 2005 NAS "RfD" does not follow the existing EPA RfD method. 

While we agree that perchlorate causes adverse effects in the manner described by EPA, and that 

EPA based its Reference Dose (RfD) principally on the work of the NAS/NRC (2005), and further 

that the NRC (2005) provided an insightful and conclusive discussion of perchlorate science, it is 

exceedingly clear that NRC did not use accepted risk assessment methods, nor EPA methods, to 

develop a reference dose. NRC concluded that hypothyroidism would be the first observed adverse 

effect, or critical effect (Faustman, and Omenn. 2001; EPA, 2008), and that the dose level at which 

this effect would likely first be observed (the no observed adverse effect level, or NOAEL) in 

healthy adults is 0.4 mg/kg-day. This choice might be appropriate basis of the RfD. 

Yet, NRC selected the lowest of several precursors to this lowest adverse effect, the threshold of 

iodine uptake inhibition, as the starting point for its reference dose (RfD), because it was "more 

health protective". As NRC clearly stated, this effect of itself does not result in any harm, and the 

dose at which it occurs is approximately 100 times lower than the NOAEL of the first adverse 

effect. Moreover, this choice of lowest precursor is not consistent with EPA guidelines. 

Specifically, NRC ignores two principles that govern calculating RfDs: 1. To identify an intake that 

"reduces hazard to a minimum and at the same time allows use of [necessary] chemicals ((Faustman, 

and Omenn. 2001)," and 2. To base RfDs on an adverse effect (Lehman and Fitzhugh, 1954), or an 

adverse effect or its precursor (Barnes and Dourson, 1988; EPA, 2002). 

That is, the definition of critical effect by EPA specifies an adverse effect or its precursor---singular-

--meaning the penultimate precursor when several are available. Thus, the RfD has been, and must 

continue to be, the largest intake that can be reasonably certain to cause no injury to the whole 
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population. Otherwise, there is no reason not to choose lower precursors for any RfDs, resulting in 

RfDs that solely depend on how many precursor effects have been monitored. 

The practice of focusing on the first adverse effect, or its known precursor, in dose response 

assessment, is based on decades of experience in the United States, Canada, and Europe. This 

practice allows us to draw conclusions about public health in the absence of observable data and in 

the presence of scientific uncertainty. The accepted process for developing RfDs (Barnes and 

Dourson, 1988) suggests two possible approaches to developing an RfD from the perchlorate data. 

The first would be to use the NOAEL of the critical effect from an adult population and apply 

uncertainty factors to account for sensitive populations and for lack of precision in defining this 

NOAEL. The second approach would be to use a NOAEL from a sensitive population. 

Following this second approach, a standard RfD of 0.002 mg/kg-day has been described that is 

adequately health-protective (Strawson et al., 2004). This RfD may be suitably upgraded with the use 

of the newer epidemiology studies, as described briefly above. 

Using a non-standard RfD process in regulating chemicals, such as that suggested by NAS (2005) for 

perchlorate, is not consistent with accepted EPA methods for developing such values. EPA’s 

acceptance of this non-standard RfD undermines its good dose response assessment work in other 

programs. 

Response: Please see the response to comment ID 20641 under comment code 2100, and the 

response to comment code 2100. 

Commenter Name: Michael Dourson 

Commenter Organization: Toxicology Excellence for Risk Assessment 

EPA Document ID: EPA-HQ-OW-2008-0692-1562 

EPA Comment ID: 20644 

EPA Comment Code: 2100 

Comment: However, we also recommend that EPA update its RfD prior to publishing a Health 

Advisory for the following reasons: 

Additional important data on pregnant women and their offspring have become available since the 

time of the development of the EPA's RfD in 2005, which necessitate a reconsideration of the 

existing value. This reconsideration is consistent with recommendations of the NAS (2005) in its 

report. 

The excellent relative source contribution evaluation of EPA, based on well supported and clearly 

described work of the FDA, necessitates a rethinking of the any RfD, since the underlying studies 

may not have measured perchlorate in the food of the human subjects. 

The 2005 "RfD" of the NAS does not follow the existing EPA method. 

Additional information is provided in the attached document. 
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Commentary on "Drinking Water: Preliminary Regulatory Determination on Perchlorate" Docket 

ID No. EPA-HQ-OW-2008-0068 Michael L. Dourson, Ph.D., DABT, ATS Joan Strawson, M.S., 

M.T.S.C., J.D. Toxicology Excellence for Risk Assessment (TERA) 

The opinions expressed in this text are those of the authors for the purpose of protecting public 

health. These authors' opinions do not necessarily represent the views of the sponsors. 

Response: See response to comment ID 20641 under response code 2100. 

Commenter Name: Robert Howd 

Commenter Organization: California Environmental Protection Agency, Water Toxicology 

Section 

EPA Document ID: EPA-HQ-OW-2008-0692-1671 

EPA Comment ID: 20646 

EPA Comment Code: 2100 

Comment: III (A)(1 and 2), pp 60266-60268. The NRC (2005) review of the Greer et al. (2002) 

study is discussed. EPA notes that the lowest dose of 7 ug/kg-day in the Greer et al. study 

corresponds to a statistical NOEL, and suggests that an uncertainty factor of 10 from the lowest 

dose is adequate to derive a health- protective level of 0.7 ug/kg-day, to account for human 

variability, as recommended by the NTP review panel. However, OEHHA would like to point out 

that the data also allow calculation of the lower confidence limit on a benchmark dose level for 

inhibition of iodide uptake. Using the lower 95% confidence limit of a 5% benchmark dose for 

inhibition of iodide uptake, OEHHA calculated a BMDL of 3.7 ug/kg-day, using EPA BMDS 

software (OEHHA, 2004). Although the low number of subjects (37) in the Greer et al. study 

cannot provide an accurate estimate of true human variability, it seems to us that using the available 

data in this calculation is a more reasonable way to account for the uncertainty in the data than just 

dividing the NOEL by 10. Our approach in fact follows the recommendations of EPA as to when 

BMD modeling should be applied. 

It should also be noted that a sensitive population (women who consume low iodide levels) has been 

identified (Blount et al., 2006), and this population was excluded from the study of Greer et al. 

(2002). An apparent additional iodide inhibitory effect was noted by Steinmaus et al. (2007) in 

women who smoke (and consume low iodine). We therefore recommend that either the BMDL of 

3.7 ug/kg-day be utilized for the calculation, or that an extra 3-fold uncertainty factor be utilized in 

the EPA NOEL/UF approach to account for the missing sensitive subpopulation and to help 

account for the known variability. 

Because the NRC panel did not have access to the data of Blount et al. (2006), relying on the NRC 

conclusions without specific acknowledgement that that approach does not address the sensitive 

population issues seems inappropriate. 

Response: See response to comment ID 20641 under comment code 2100. EPA agrees with the 

commenter’s suggestions regarding the review and evaluation of additional new data regarding the 

health effects of perchlorate, and will do so as part of the perchlorate regulatory process. 

Commenter Name: Brie Brigham 

Commenter Organization: 
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EPA Document ID: EPA-HQ-OW-2008-0692-1436 

EPA Comment ID: 20895 

EPA Comment Code: 2100 

Comment: The EPA has set an official reference dose of .0007 mg/kg/day of perchlorate, which is 

not expected to cause adverse health effects in humans. The EPA then converted this reference 

dose into a drinking water equivalent level of 24.5 ppb by assuming a person weighs 154 pounds and 

consumes 68 ounces of drinking water per day over a lifetime. Based on these conversions, the 

drinking water equivalent level for infants should be 4.35 ppb. The EPA assumes that a perchlorate 

contamination level of 15 ppb is safe. However, this level more than triples the level assumed safe 

for infants. 

Response: The NRC (2005) identified "the fetus of pregnant women who might have 

hypothyroidism or iodide deficiency" as "the most sensitive population," but also identified infants 

and developing children as additional "sensitive populations." Infants and young children have 

greater exposure to contaminants in food and water because of greater consumption of food and 

water on a per unit body weight basis. See response to comment code 5220 for a discussion of 

alternative Health Reference Levels. National Research Council (NRC). 2005. Health Implications of 

Perchlorate Ingestion. National Academies Press, Board on Environmental Studies and Toxicology, 

January, 2005, Washington, D.C. 276 p. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20900 

EPA Comment Code: 2100 

Comment: Compounding these problems, the CIIT relied heavily on a flawed, industry-funded 

study (the Greer study) when creating the computer model (Greer et al. 2002) - the problems with 

the Greer study have been documented in the published scientific literature and by the 

Massachusetts Department of Environmental Protection (Ginsberg and Rice 2005, MassDEP 2006). 

Response: EPA believes that the Greer study, selected by the NRC as the basis for the RFD, 

represents the best available study for deriving a RfD. See response to comment code 2100. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20911 

EPA Comment Code: 2100 

Comment: The PBPK model relies heavily on industry-funded Greer study: The CIIT generated 

PBPK model uses data from the Greer study, which showed a dose-dependent decrease in iodine 

uptake (RAIU) by the thyroid gland with increasing perchlorate ingestion (Greer et al. 2002). This 

study included only 37 participants who were divided into several study groups and administered 

different doses of perchlorate for 14 days; the researchers determined that 0.007 mg/kg/day was the 

no observed effect level (NOEL) for perchlorate. The results from this study were used by the 

National Academy of Sciences (NAS) in setting the reference dose for perchlorate of 0.7 ug/kg/day. 
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However, the Greer study results and assumptions drawn from these results have been questioned 

in a peer-reviewed article that was published in Environmental Health Perspectives in 2005 

(Ginsberg and Rice 2005). Two toxicologists, one from the Connecticut Department of Public 

Health and the other from the Maine Bureau of Health, conducted an analysis of the raw data from 

the Greer study and concluded that the "Individual results of Greer et al. point to an effect in four 

of the seven individuals tested at the lowest dose (0.007 mg/kg/day), indicating that this dose is an 

effect level." In other words, while Greer et al. and the NAS both concluded that 0.007 mg/kg/day 

is a NOEL, closer analysis of the data reveals that several of the 7 study subjects in this group 

experienced effects at this dose, thereby invalidating 0.007 mg/kg/day as a NOEL. 

The Massachusetts Department of Environmental Protection (Mass DEP), which has set the most 

stringent drinking water standard for perchlorate nationally, had the following observations about 

the Greer study: 

"MassDEP has concerns about the lowest dose in the Greer study being a no-effect level based on 

the facts that: due to the small number of subjects in the lowest dose group, there is low power to 

detect a statistically significant effect; averaging of group responses obscures positive individual 

inhibition; a non- statistically significant IUI (iodine uptake inhibition) effect was observed at the 

lowest dose tested; and, good low dose corroborating data is lacking" (MassDEP 2006). 

In light of these valid criticisms of the Greer study, it is unclear why EPA chose to rely so heavily on 

the PBPK model that incorporates data from this study while essentially ignoring much more 

relevant data from the CDC. 

Response: Blount et al., (2006) found that perchlorate exposure was a statistically significant 

predictor of thyroid hormones in women, but not in men. Their observations that adverse thyroid 

hormone effects were found in women whose urinary iodine was below 100 ug/L is suggestive of a 

partial study population iodine deficiency status. Blount et al. (2006) also noted several limitations of 

their study. Since their study was cross-sectional in design, it also cannot be concluded whether or 

not the association between perchlorate and thyroid hormone levels is causal, or is mediated by 

some other correlate of both. Blount et al., (2007) found that almost all participants in the same 

2001-2002 NHANES survey, including the participants in their 2006 study, had urinary levels of 

perchlorate corresponding to estimated dose levels that are below the RfD of 0.7 ug/kg/day. 

The NRC recommended that data from the Greer et al. (2002) human clinical study be used as the 

basis for deriving a perchlorate reference dose (RfD) (NRC 2005), and also noted that the results of 

this study were supported by those of other human studies. From this Greer et al. (2002) human 

clinical study, the statistical no observed effect level (NOEL) for the perchlorate-induced inhibition 

of thyroid iodide uptake was determined to be 7.0 ug/kg (a corresponding iodide uptake inhibition 

of 1.8%). The NRC recommended that EPA apply an uncertainty factor of 10 to this NOEL of 7.0 

ug/kg for the perchlorate-induced inhibition of thyroid iodide uptake, to account for differences in 

sensitivity between healthy adults and the most sensitive sub-population, consisting of fetuses of 

pregnant women who might have hypothyroidism or iodide deficiency. 

EPA evaluated the published PBPK models (Clewell et al., 2007, and Merrill et al., 2005) and used 

them to further explore the relationship between water concentrations and iodide uptake inhibition 

in different subpopulations (USEPA, 2008). However, EPA did not rely on this PBPK analysis for 

determining the HRL. Rather, the HRL of 15 μg/l was calculated directly from the RfD to protect 
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the most sensitive subpopulation, the fetuses of pregnant women, using high end exposure 

assumptions. EPA thus applied the adjusted model to the HRL of 15 μg/l to determine the 

predicted percent RAIU inhibition (USEPA, 2008), and found that the 2.2 percent inhibition level 

for 7-day old bottle fed infants is comparable to the 1.8 percent inhibition level that the NRC 

identified as a no effect level in healthy adults and recommended as the point of departure for 

calculating the RfD (NRC, 2005). So, the modeling essentially agrees with the original NRC 

conclusions, and yielded results comparable to or below the 1.8 percent no effect inhibition level 

from the Greer (2002) study. 

EPA used the best available peer-reviewed science, and the Agency has determined to regulate 

perchlorate in drinking water. 

Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell KL. Environ Health Perspect. 2006 

Dec;114(12):1865-71. Blount BC, Valentin-Blasini L, Osterloh JD, Mauldin JP, Pirkle JL. J Expo Sci 

Environ Epidemiol. 2007 Jul;17(4):400-7. Clewell RA, Merrill EA, Gearhart JM, Robinson PJ, 

Sterner TR, Mattie DR, Clewell HJ 3rd. J Toxicol Environ Health A. 2007 Mar 1;70(5):408-28. 

Greer MA, Goodman G, Pleus RC, Greer SE. Environ Health Perspect. 2002 Sep;110(9):927-37. 

Merrill EA, Clewell RA, Robinson PJ, Jarabek AM, Gearhart JM, Sterner TR, Fisher JW. Toxicol Sci. 

2005 Jan;83(1):25-43. National Research Council (NRC). 2005. Health Implications of Perchlorate 

Ingestion. National Academies Press, Board on Environmental Studies and Toxicology, January, 

2005, Washington, D.C. 276pp. USEPA. 2008. Inhibition of the Sodium-Iodide Symporter By 

Perchlorate: An Evaluation of Lifestage Sensitivity Using Physiologically Based Pharmacokinetic 

(PBPK) Modeling. U.S. Environmental Protection Agency, Washington, D.C., 2009. 

Commenter Name: Caroline Baier-Anderson, PhD 

Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20945 

EPA Comment Code: 2100 

Comment: The EPA Reference Dose is not Adequately Protective of Human Health 

The EPA Reference Dose is based on a Limited Study 

The EPA Reference Dose for perchlorate is based on data from Greer et al. (2002) that observed 

the inhibition of radioiodide uptake. Ginsberg and Rice (2005) identified several problems with the 

Greer study that suggest the need for a reevaluation of the value that serves as the foundation for 

regulatory decision- making: 

* Several individuals in the low dose group appear to demonstrate a response to perchlorate that is 

not evident in the reported mean. In analyzing this study, the National Academy of Sciences used 

the average response, and the significant variability in the response likely diminished the impact (e.g., 

as a result of reduced statistical power) of those showing a response. 

* Ginsberg and Rice also point out that the apparent non-significant response resulted in the NAS 

characterizing the dose as a NOAEL, rather than a LOAEL. In their paper Ginsberg and Rice 

suggest an alternative interpretation that "[t]he data of Greer et al. (2002) point toward a more 

sensitive subgroup, which in this case represents more than half of the test group but is not evident 
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in the group mean analysis due to the variable nature of the response." If this is indeed the case then 

we can expect that there will be a wide range of susceptibility to perchlorate effects in the larger 

population. 

Response: See response to comment ID 20641 under comment code 2100. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20957 

EPA Comment Code: 2100 

Comment: 2. The very particular case of perchlorate: Total effective perchlorate NOEL and RfD 

-These food and drinking water perchlorate background levels are now known also for the U.S. 

population. 

-These food and drinking water perchlorate background level are very low 

-Therefore adding the background perchlorate level to the Greer (nominal) NOEL does not 

significantly increase the effective NOEL (from 7.0 to 7.04 ug/kg-day) 

-However what significantly increases the nominal NOEL is the also known equivalent perchlorate 

background level caused by nitrate and thiocyanate and which results in an effective perchlorate 

equivalent NOEL of 12.8 ug/kg-day instead of 7 ug/kg-day. 

Response: EPA believes that the Greer study as designed and interpreted by the authors is the 

appropriate interpretation. Addition of a correction for other sources would significantly bias the 

results. This is especially true given that the measured change in RAIU was a change relative to the 

start of the study, not an uncorrected measure. The use of the start of study measure effectively 

corrected for any background levels that existed on a subject by subject basis. Also, see response to 

comment code 2100. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20963 

EPA Comment Code: 2100 

Comment: The NRC RfD on itself was based on the Greer et al., 2002(1) critical study. 

NRC believed that the Greer study cohort that had been administered the perchlorate dose-response 

doses, was, in terms of competitive iodine uptake inhibition caused by perchlorate (and, we suppose, 

by goitrogens in general), representative for the adult US population excluding the more sensitive 

subpopulations (The RfD took into account these subpopulations by applying an uncertainty factor, 

UF). 
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Conversely if this cohort would not have been representative for this (general) segment of the US 

population, the Greer study outcome wouldn’t have been so either and therefore the resulting RfD 

couldn’t have been assumed to be health protective for the US population either. 

To our knowledge no argument has emerged that put in doubt the representativeness of the Greer 

cohort. 

Response: EPA agrees. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20965 

EPA Comment Code: 2100 

Comment: The Greer study is a type 3 set-up (see section 1.3 below). 

EPA asserts that it was applying a "default" RSC to estimate its former recommended DWEL 

(Drinking Water Equivalent Level) of 24.5 ppb issued in 2005 and based on the Greer study . With 

all due respect, EPA rather found that the RSC was not applicable for the reasons explained before. 

Indeed arriving at a 24.5 ppb DWEL from the RfD of 0.70ug/kg-day implies a RSC equal to 1 

according to above equation with BW= 70 kg and DW =2l/day. 

1.3. The Greer trial set-up 

The Greer study cohort, in order to determine dose-response effects, received several oral doses of 

perchlorate. 

Those doses were in addition to their background perchlorate levels originating from DW and food 

background sources. 

The Greer trial was thus a type 3 set-up. 

In fact the real NOEL for perchlorate alone (NOEL2) was not 0.7ug/kg-day as generally assumed 

but 0.7ug/kg-day plus the background from food + water. Thus in fact the 0.7ug/kg-day Greer 

NOEL (NOEL1) was an approximate or nominal level. 

Establishing DW maximum contaminant levels based on trials where the contaminant is already 

consciously present in the background are not frequent but precedents do exist. 

* The MCL of 2 ppm for barium was based on Wones R.G et al, Lack of Effect of Drinking Water 

Barium on Cardiovascular Risk Factors, Environmental Health Perspectives Volume 85, 1990, a 

critical human study, analogue to the Greer 2002. 

We quote from Massachusetts Department of Environmental Protection: 

http://www.mass.gov/dep/water/drinking/standards/barium.htm: "The MCLG is based on the 

RfD (presented below) derived from the Wones et al., study. It assumes that a 70 kg adult ingests 2 
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L/day of water. Since this value is based on a human study that considers contributions from food 

and air, no relative source contribution was applied for drinking water exposures" 

* Also the nitrate MCL of 10 ppm N (as nitrate) was based on 2 critical human studies: 

-Bosch H et al., (1950). Methemoglobinemia and Minnesota well supplies. Journal of the American 

Water Works Association 42:161-70, 1950 and 

-Walton G (1951). Survey of literature relating to infant Methemoglobinemia due to nitrate 

contaminated water. Am. J. Public Health 41:986-96, 1951. There the RSC was considered as "not 

applicable" i.e. equal to 1.The RSC was not applicable because it did not have sense to apply it. 

* The same reasoning went into the Cal. PHG (Public Health Goal) for fluorine: with an RSC = 

100% followed by this 

Comment: "OEHHA assumes that the populations under study exhibited comparable dietary and 

hygiene exposures to fluoride. Therefore, the relative source contribution factor is 100% to account 

for equal exposure of study populations to fluoride from sources other than drinking water 

(http://oehha.ca.gov/water/phg/pdf/fluor_c.pdf) 

This is the same as saying that the study cohort was representative for the California population and 

that therefore the average background, which already contained fluorine, should have been so too. 

Response: No response is necessary to the information provided by the commenter. Also, see 

response to comment code 2100. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20967 

EPA Comment Code: 2100 

Comment: B. The other goitrogens that are part of the background should be taken into account. 

Most of the time, each contaminant has its own mode of action different from others or on different 

moments. 

This is not the case for NIS (Sodium Iodine Symporter) related inhibitors of iodine uptake such as 

nitrate, perchlorate and thiocyanate which are competitive inhibitors with simultaneous joint effects 

(4). 

Once again, to our knowledge this is the first time that background data are available also for the 

other goitrogens .This would allow to calculate an even more refined NOEL (NOEL4) and a 

corresponding HRL i.e. HRL4 

In the Blount study those goitrogens were controlled for and evaluated when testing the relationship 

of perchlorate with T4 and TSH thyroid hormones. Average urinary(U) thiocyanate and nitrate 

levels were 1.2 (1.08-1.33 at 95% CI) and 38 mg/l (35.9-40.3 at 95% CI) respectively which, when 
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applying the relative potencies compared with perchlorate of 1/15 and 1/240(2) respectively, 

translated into 80 and 158 ug /L respectively. 

80 ug /L U thiocyanate corresponds with about 2.8 ug/kg-day cyanide dietary uptake, applying the 

same regression as for perchlorate and assuming a 40% urinary recovery from cyanide and 

thioglucosides, the precursors of thiocyanate (5, 6). 

158 ug /L U nitrate corresponds with about 3.0 ug/kg-day nitrate dietary uptake, applying the same 

regression as for perchlorate and assuming a 75 % urinary recovery (7, 8). 

The total average perchlorate equivalent background is therefore estimated at 0.04 + 2.8 + 3.0 =5.8 

ug/kg-day. 

This comes down to trial set-up type 3 instead that the DW perchlorate BG plus the perchlorate 

equivalent BG should be added to the RfD and with RSC =1 since all contributors are now captured 

in the effective total equivalent NOEL (= NOEL4) and RfD (=RfD4) as shown in the following 

equations and fig.4 : 

NOEL4= NOEL1 dose +FBG+ DWBG + PEBG. 

RfD4= NOEL4/UF= NOEL4/10 

HRL4 = [(RfD3 +PEBG) Ã— BW)/DWI] Ã— RSC= [(RfD4) Ã— BW)/DWI] x 1 

Fig. 4: NOEL based on dose-response trial with perchlorate food background and with drinking 

water background: perchlorate equivalent background. [see PDF Docket ID EPA-HQ- OW-2008-

0692-1798] 

So the background levels of the other 2 goitrogens are substantially more relevant than the 

perchlorate back ground level itself. 

This increases the effective perchlorate equivalent NOEL (NOEL4) to 7 ug/kg-day +5.8 ug/kg-day 

= 12.8 ug/kg-day which would have lead to a total goitrogen RfD4 of 1.28 ug/kg-day and a DW 

HRL4 of 44.8 ppb for perchlorate and nitrate/240 together (Thiocyanate in DW is negligible in the 

absence of a point source contamination). 

Indeed when applying an RSC =1, BW= 70kg and DWI = 2 l/day, the HRL equation becomes: 

HRL4 = [(RfD4 Ã— BW)/DWI] Ã— RSC = 44.8 ppb =45 ppb 

So the perchlorate equivalent effect due to the other 2 goitrogens has a much larger impact on the 

final optimal HRL (HRL4) than the perchlorate background itself but has not been taken into 

consideration. 

Response: While EPA acknowledges that nitrate and thiocyanate have the same mode of action as 

perchlorate, and that the effects of combined exposure to perchlorate, nitrate, and thiocyanate are 

additive, EPA does not believe there are sufficient scientific data currently available to assess and 

characterize the combined risk of these contaminants. EPA has committed to a drinking water 
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strategy that outlines four principles to expand public health protection for drinking water. One of 

these principles is to address contaminants as groups. However, EPA does not believe that 

regulatory action to address perchlorate should be further delayed. Therefore, EPA intends to 

develop a proposed rule for perchlorate. At such time as a NPDWR is promulgated, EPA is 

required to review and revise, as appropriate, its drinking water standards at least every six years. 

Any revision must at least maintain or improve public health protection. When there are sufficient 

scientific data to assess the cumulative risks of perchlorate and other contaminants, EPA will review 

this information to evaluate whether any new or revised NPDWRs are appropriate. 

Commenter Name: 

Commenter Organization: Ag Council et al 

EPA Document ID: EPA-HQ-OW-2008-0692-1987 

EPA Comment ID: 20975 

EPA Comment Code: 2100 

Comment: The NAS Study is the Most Comprehensive Scientific Review on the Health Effects of 

Perchlorate to Date. 

We support EPA's decision to rely on the recommendations of the NAS perchlorate review panel in 

deriving a reference dose (RfD). From our perspective, the NAS panel conducted a thorough 

scientific inquiry of the available health effects literature in a highly professional and independent 

manner. The Panel's 2005 recommendations, based upon the best science then available, continue to 

be validated by new scientific studies on perchlorate health effects and exposures. It is critically 

important to bear in mind that the NAS panel views the perchlorate RfD as providing a large margin 

of safety because it is based on a No-Observed-Effect-Level (NOEL) as opposed to EPA's 

traditional approach of deriving the RfD from a No-Observed-Adverse-Effect-Level (NOAEL). 

The NOEL is a precursor effect (inhibition of iodine uptake by the thyroid) to an actual adverse 

effect (hypothyroidism). The RfD also incorporates a 10-fold safety factor to account for variability 

in the human population. For these reasons, the NAS views the RfD as highly health protective, 

even for sensitive subpopulations. 

Response: See response to comment code 2100. 

Greer MA, Goodman G, Pleus RC, Greer SE. Health effects assessment for environmental 

perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake in 

humans. Environ Health Perspect. 2002 Sep;110(9):927-37. Erratum in: Environ Health Perspect. 

2005 Nov;113(11):A732. National Research Council (NRC). 2005. Health Implications of 

Perchlorate Ingestion. National Academies Press, Board on Environmental Studies and Toxicology, 

January, 2005, Washington, D.C. 276pp. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20984 

EPA Comment Code: 2100 

Comment: A reference dose (RfD) is an estimate of the daily exposure to an agent over a full 

lifetime that is "likely to be without an appreciable risk of deleterious effects" for the human 
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population, including sensitive subgroups.[FN13: EPA Integrated Risk Information System (IRIS) 

Glossary of terms. http://www.epa.gov/ncea/iris/help_gloss.htm#r] In 2005, the National 

Research Council (NRC) of the National Academy of Sciences recommended an RfD for daily 

intake of perchlorate that it considered to be an acceptable level of exposure of 0.7 

ug/kg/day.[FN14: NRC. 2005. Health Implications of Perchlorate Ingestion. National Research 

Council of the National Academies. National Academies Press, Washington, D.C.] EPA adopted 

this RfD and posted on its public database, the Integrated Risk Information System (IRIS) in 

February 2005.[FN15: EPA IRIS assessment of perchlorate. 

http://www.epa.gov/NCEA/iris/subst/1007.htm] 

Response: No response is necessary to the information provided by the commenter. Also, see 

response to comment code 2100. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20986 

EPA Comment Code: 2100 

Comment: The RfD for perchlorate and perchlorate salts of 0.7 ug/kg body weight/day is based on 

a human volunteer study, Greer et al, 2002.[FN16: Greer, M.A., Goodman, G., Pleuss, R.C., Greer, 

S.E. 2002. Health effect assessment for environmental perchlorate contamination: The dose 

response for inhibition of thyroidal radioiodide uptake in humans. Environ. Health Perspect. 

110:927-937.] The RfD is for oral exposure, including food and water, and is based on radioactive 

iodide uptake inhibition (RAIU) in the thyroid as the critical effect. The IRIS assessment of 

perchlorate explains that "The point of departure is based on a non-statistically significant mean 

1.8% (standard error of the mean 8.3%) decline in RAIU in healthy adults following two weeks 

exposure to a daily perchlorate dose of 0.007 mg/kg/day. An intraspecies uncertainty factor of 10 is 

applied to protect the most sensitive population, the fetuses of pregnant women who might have 

hypothyroidism or iodide deficiency. Dose is given as perchlorate anion."[FN17: EPA. IRIS 

database. Perchlorate and perchlorate salts. http://www.epa.gov/ncea/iris/subst/1007.htm#revhis] 

Response: No response is necessary to the information provided by the commenter. Also, see 

response to comment code 2100. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20987 

EPA Comment Code: 2100 

Comment: The RfD adopted by EPA has been widely criticized as inadequately protective by state 

scientific experts[FN18: Ginsberg G and D Rice. The NAS perchlorate review: questions remain 

about the perchlorate RfD. Environ Health Perspect. 2005 Sept; 113(9):1117-9. Erratum in: Environ 

Health Perspect. 2005 Nov; 113(11):A732.] and by EPA's own Children's Health Protection 

Advisory Committee,[FN19: Letter from Melanie Marty to Administrator Johnson regarding 

Preliminary Regulatory Determination on Perchlorate (November 3, 2008, PDF) 

http://yosemite.epa.gov/ochp/ochpweb.nsf/content/perchlorateletter.htm/$file/Per 
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chlorateLetter.pdf] and no longer reflects the best available data.[FN20: EN Pearce, AM. Leung, BC 

Blount, HR Bazrafshan, X He, S Pino, L Valentin-Blasini, and LE Braverman, 2007. Breast milk 

iodine and perchlorate concentrations in lactating Boston-area women. J Clin Endocrinol Metab. 

92(5):1673-7.] [FN21: Letter from Melanie Marty to Administrator Johnson regarding Preliminary 

Regulatory Determination on Perchlorate (November 3, 2008, PDF) 

http://yosemite.epa.gov/ochp/ochpweb.nsf/content/perchlorateletter.htm/$file/Per 

chlorateLetter.pdf] However, even when basing its decision upon this unacceptably high RfD, 

EPA's preliminary determination not to regulate perchlorate would still expose hundreds of 

thousands of children and infants to unsafe levels of perchlorate. 

Response: EPA respectfully disagrees with the commenter. See response to comment code 2100. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20994 

EPA Comment Code: 2100 

Comment: D. EPA relies on the RfD based on the comparatively weak Greer et al study to 

determine the HRL 

In simple terms, the HRL is the maximum tolerable amount of perchlorate that could be in drinking 

water, considering that perchlorate is also in food, and still keep daily consumption levels from 

exceeding the RfD. The HRL was calculated as follows: For all populations, including pregnant 

women, EPA determined that the RfD is 0.7 ug/kg/day. This value is posted on the IRIS database 

based on recommendations from a committee of the National Academies. EPA reports that for 

pregnant women, exposure to perchlorate from food is 0.263 ug/kg/day at the 90th percentile 

(based on data from a national food survey), representing nearly 38% of the RfD, thus leaving an 

RSC (relative source contribution) for water of 62% (FR at 60276). This is equivalent to 0.437 

ug/kg/day from water, assuming an average body weight of 70 kg, and a daily water consumption of 

2 L (90th percentile adult water consumption). That is, 0.437 ug x 70 kg body wt. = 30.6 ug 

perchlorate in 2 L (the daily consumption amount). This is 15 ug/L, or 15 ppb, the HRL. 

Because the dose-response relationship used to determine the RfD is derived exclusively from the 

Greer et al study, the HRL also is dependent on the Greer et al study to determine the maximum 

allowable level of drinking water contamination. 

The Greer et al study [FN34: Greer MA, G Goodman, RC Pleus, and SE Greer. 2002. Health 

effects assessment for environmental perchlorate contamination: the dose- response for inhibition 

of thyroidal radioiodine uptake in humans. Environ Health Perspect 110:927-937.] reported on 

study results from intentional dosing of a small population (N=37) of healthy men and women, for 

only two weeks, and the study lacked measurements of iodine status that is now known to be a 

critical variable. Other serious problems with the Greer study included the fact that the low dose 

group contained only seven participants including only six women. Use of these limited data to 

calculate a regulatory trigger level has been widely criticized as inadequate by state scientific 

experts[FN35: Ginsberg G and D Rice. The NAS perchlorate review: questions remain about the 

perchlorate RfD. Environ Health Perspect. 2005 Sept; 113(9):1117-9. Erratum in: Environ Health 

Perspect. 2005 Nov; 113(11):A732.] and by EPA's own Children’s Health Protection Advisory 
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Committee,[FN36: Letter from Melanie Marty to Administrator Johnson regarding Preliminary 

Regulatory Determination on Perchlorate (November 3, 2008, PDF) 

http://yosemite.epa.gov/ochp/ochpweb.nsf/content/perchlorateletter.htm/$file/Per 

chlorateLetter.pdf] and no longer reflects the best available data.[FN37: EN Pearce, AM. Leung, BC 

Blount, HR Bazrafshan, X He, S Pino, L Valentin-Blasini, and LE Braverman, 2007. Breast milk 

iodine and perchlorate concentrations in lactating Boston-area women. J Clin Endocrinol Metab. 

92(5):1673-7.][FN38: Letter from Melanie Marty to Administrator Johnson regarding Preliminary 

Regulatory Determination on Perchlorate (November 3, 2008, PDF) 

http://yosemite.epa.gov/ochp/ochpweb.nsf/content/perchlorateletter.htm/$file/Per 

chlorateLetter.pdf] Despite these limitations, careful analysis of the Greer data reveal clear evidence 

of perchlorate toxicity in the low-dose group; three subjects showed no perchlorate effect, but four 

subjects in the low-dose group had a measurable decrease in iodide uptake commensurate with 

perchlorate exposure.[FN39: For a complete analysis of the NAS review of perchlorate, see: 

Ginsberg G and D Rice. The NAS perchlorate review: questions remain about the perchlorate RfD. 

Environ Health Perspect. 2005 Sept; 113(9):1117-9. Erratum in: Environ Health Perspect. 2005 

Nov; 113(11):A732.] Because the study authors relied on averaged data rather than individual data, 

the more sensitive individuals in the study group were obscured 

The short duration of the Greer study, only 14 days, creates considerable uncertainty that the 

cumulative effect of longer-term exposure are accounted for. A study in rats found greater 

perchlorate toxicity to the thyroid from 90- day exposure than from 14-day exposure (Springborn 

Laboratories 1998), suggesting that cumulative exposure may cause significant systemic injury that is 

not detectable in a short-term study. Although one longer-term (six month) human study with 13 

volunteers has been promoted by industry as indicating that humans adapt to long-term exposure 

(Braverman et al. 2006[FN40: Braverman LE, EN Pearce, X He, S Pino, M Seeley, B Beck, B 

Magnani, BC Blount, and A Firek. 2006. Effects of six months of daily low-dose perchlorate 

exposure on thyroid function in healthy volunteers. J Clin Endocrinol Metab. Jul; 91(7):2721-4. 

Epub 2006 Apr 24.]) this study was unlikely to have adequate statistical power to detect an effect, 

especially given the particular vulnerability for some populations. The Blount (2006) study showed 

that some people are much more vulnerable to perchlorate toxicity than the average population; 

women are more sensitive than men, iodine-deficient women are more sensitive than iodinesufficient women, and iodine-deficient women with TSH levels on the high end of the normal range 

are even more sensitive than other iodine-deficient women.[FN41: Blount BC, Pirkle JL, Osterloh 

JD, Valentin-Blasini L, Caldwell KL. Urinary perchlorate and thyroid hormone levels in adolescent 

and adult men and women living in the United States. Environ Health Perspect. 2006 

Dec;114(12):1865-71.] Other human studies suffer from the same limitations. For example, a study 

of chronically perchlorate-exposed pregnant women in Chile[FN42: Tellez RT, PM Chacón, CR 

Abarca, BC Blount, CB Van Landingham, KS Crump and JP Gibbs. 2005. Long-term environmental 

exposure to perchlorate through drinking water and thyroid function during pregnancy and the 

neonatal period. Thyroid 15(9):963-975.] that also failed to find an effect of perchlorate exposure 

had only three iodine- deficient female subjects out of 183. 

Response: Regarding this comment encouraging EPA to review additional data to support the 

perchlorate regulatory determination, EPA will continue to rely on the best available science as it 

proceeds through the rulemaking process. 
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Please see the response to comment ID 20987 under comment code 2100, and the response to 

comment code 2100 for a discussion of the RfD. Please see the response to comment code 5220 for 

a discussion of alternative Health Reference Levels. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20999 

EPA Comment Code: 2100 

Comment: EPA tries to support its conclusions that the HRL is safe by avoiding referring to the 

RfD, and instead referring to the level of inhibition of RAIU on which the NRC report (NRC, 2005) 

based its recommended RfD.[FN54: 73 Fed. Reg. at 60277.] EPA cannot pretend that its own RfD 

does not exist, and shift its evaluation of acceptable exposure estimates to a discrete biological 

endpoint. 

Response: Please see the response to comment code 5220 for a discussion of alternative Health 

Reference Levels. Please see the response to comment ID 20987 under comment code 2100, and 

the response to comment code 2100. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-2082 

EPA Comment ID: 21022 

EPA Comment Code: 2100 

Comment: 5. Your letter also raises concerns with the Greer et al. study, stating that the RfD is 

uncertain and not necessarily a health protective benchmark because Greer was a short-term study 

with a small sample size. 

The NAS perchlorate panel addressed this very issue at length in their comprehensive report, 

pointing out that there were four doses across 37 subjects. Second, the panel concluded that since 

the point of departure is based upon IUI- a short-term event- any chronic effects "would have no 

greater effect" than any short term effects that may occur (NAS, 2005). Importantly, the NAS also 

noted that it did not examine Greer in isolation. The NAS noted that the findings in Greer are 

supported by other clinical studies, occupational and environmental epidemiological studies, and 

studies of long-term perchlorate administration to patients with hyperthyroidism. ATSDR reviewed 

all the literature in its 2008 toxicology document and still agrees that Greer et al. (2002) is the best 

study to determine a point of departure for a toxicity guideline value. 

Response: Please see response to comment code 2100. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21056 

EPA Comment Code: 2100 
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Comment: [Text Box: On basing an RfD on a no effect level for a non adverse effect, the NRC 

states: "Inhibition of iodide uptake by the thyroid clearly is not an adverse effect; however if it does 

not occur, there is no progression to adverse health effects."] 

For this current regulatory determination, EPA has the benefit of a rigorous and independent peer 

review of the available science. These include the study by the NRC and more recently the Agency 

for Toxic Substances and Disease Registry, an agency of the Department of Human Health Services 

(ATSDR, 2008). 

In 2005, the NRC perchlorate panel reached a consensus and recommended an RfD of 0.0007 

mg/kg per day. The NRC panel comprised 15 leading scientists and physicians with wide-ranging 

expertise necessary to evaluate all aspects of the available science related to perchlorate. The NRC 

process occurred over a 15- month time period, providing ample time for the panel to review studies 

and consider oral testimony and written comments prior to issuing its conclusions and 

recommendations. As part of this process, the NRC panel performed an exhaustive review of the 

wide body of available animal and human studies as well as other scientific data relevant to 

understanding the health effects of perchlorate. The NRC panel noted that "emphasis was given to 

studies with the soundest scientific methods to draw conclusions regarding the effects of perchlorate 

exposure" (NRC, 2005). 

The charge to the Committee was to "critically evaluate the scientific literature, including both 

human and animal data, and...assess the key studies underlying EPA's 2002 Draft Toxicological 

Review and Risk Characterization for Perchlorate in terms of quality, reliability, and relevance to 

draw conclusions about the health implications of exposure to low levels of perchlorate in drinking 

water." As stated in the NRC Committee Report, "EPA has been criticized that it did not 

appropriately consider all the relevant data for its assessments and that it based its conclusions on 

flawed scientific studies" (NRC, 2005). 

The NRC independently evaluated the science which was published in the report Health 

Implications of Perchlorate Ingestion (2005). The NRC report recommended an RfD of 0.7 ug/kg-d 

based on a No Observed Effect Level (NOEL), or the dose at which no effects occur, adverse or 

otherwise (NRC, 2005). One of the critical studies that served as the basis for this RfD was the study 

by Greer et al. (2002) which demonstrated that there was no inhibition of iodide uptake by the 

thyroid at a dose of 7 ug/kg-d. Importantly, the NRC did not examine Greer in isolation. According 

to the NRC report, the findings in Greer are supported by other clinical studies, occupational and 

environmental epidemiologic studies, and studies of long-term perchlorate administration to patients 

with hyperthyroidism. 

Further, the NRC states with emphasis, "Inhibition of iodide uptake by the thyroid clearly is not an 

adverse effect; however if it does not occur, there is no progression to adverse health effects." The 

committee views its recommendation to use [IUI] by the thyroid as the basis of the perchlorate risk 

assessment to be the most health-protective and scientifically valid approach (NRC, 2005). 

[Text Box: After review all scientific data, including studies since the release of the NRC perchlorate 

review, ATSDR has adopted the EPA's chronic RfD recommended by the EPA (2005) for the 

chronic MRL"] 
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In using a NOEL, the NRC committee was conservative as this dose is already lower than any dose 

in which adverse effects occur; a safety factor of 10 is further applied to the already conservative 

NOEL to account for the most sensitive individuals in a population, in this case, hypothyroid or 

iodine- deficient pregnant women and their developing fetuses. The NRC panel stated that using a 

NOEL as the point of departure is a more conservative and health- protective approach than EPA's 

customary approach of using the adverse effect (NRC, 2005). Thus, for example, the use of IUI as a 

point of departure is a more cautious health protective approach than using changes in thyroid 

hormones (a precursor to possible adverse effects) or to some adverse effect such as 

hypothyroidism. 

The panel also took time to differentiate between a NOAEL and a NOEL, finding that there was 

confusion between the two and stating that the NOAEL is based upon an adverse effect, whereas 

the NOEL is based upon a nonadverse effect (NRC, 2005). With the incorporation of an 

uncertainty factor of 10, the RfD recommended by the NRC was many times lower than the point at 

which adverse effects occur. It should be noted that the NRCNRC report concluded that no other 

uncertainty factors were necessary. Specifically on the issue of adequacy of database, the NRC 

concluded that the database contained sufficient studies from which to determine an RfD, finding 

that the database contained both human and animal data from which to evaluate IUI. The NRC also 

concluded that no LOAEL to NOAEL conversion factor was required, since the point of departure 

was the NOEL, again, a more conservative approach. Some have also argued that the Greer study 

was of short duration and have argued for a subchronic to chronic extrapolation. On that issue, the 

NRC concluded that since the point of departure is based upon IUI-a short-term event-any chronic 

effects "would have no greater effect" than any short term effects that may occur. (NRC, 2005). 

The EPA has based its RfD for perchlorate and Integrated Risk Information System (IRIS) 

summary on the NRC report. 

Response: No response is necessary to the information provided by the commenter. Also, see 

response to comment code 2100. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21059 

EPA Comment Code: 2100 

Comment: It should be noted that the RfD aims to protect the most sensitive individuals within a 

population (i.e., pregnant women and their fetuses). While some have argued that the infant or child 

is the more sensitive individual in the population; the experts of the Perchlorate NRC committee, 

EPA, ATSDR, OEHHA, and others, disagree. In addition, no reliable scientific data at relevant 

environmental exposures for this change in sensitive population has been put forward. One of the 

central considerations in these arguments is the disregard of dose and exposure. Any chemical at a 

sufficient dose will cause an adverse effect. 

[Text Box: Studies published since the NRC report in 2005 add to an already well-developed 

database, adding more studies that are consistent to previous analyses and reducing uncertainty. 

Thus, the science supports EPA's decision that the current RfD for perchlorate is both conservative 

and health protective to even the most sensitive individuals.] 
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However, dose is a foundational tenant of the standard medical sciences (e.g., toxicology, 

endocrinology, pharmacology, etc.). Dose consideration is an absolute foundation of the risk 

assessment process by all recognized authoritative bodies. 

Response: See response to comment code 2100. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21067 

EPA Comment Code: 2100 

Comment: First, as stated above, ATSDR (2008) reviewed this study in their assessment and did 

not feel that it merited any special consideration over other studies in the well developed perchlorate 

literature database. They state that their decision "...was made after a careful evaluation of the NRC 

report and of studies that have been published after the NRC (2005) report. The results from newer 

studies do not change the bottom-line recommendation" (ATSDR, 2008). 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21094 

EPA Comment Code: 2100 

Comment: EPA has provided sufficient support for its findings under the SDWA. To take the 

statutory criteria in turn: 

May perchlorate have an adverse effect on the health of persons? 

Everything - including water itself - may cause an adverse effect if the dose is sufficiently high. The 

plain meaning of the first criterion relates to the dose of the contaminant at levels which people are 

likely to be exposed to through drinking water. 

The scientific literature is clear that perchlorate will not cause adverse effects at the concentrations 

under review here. The NAS report declares, 

An important point is that inhibition of thyroid iodide uptake is the only effect that has been 

consistently documented in humans exposed to perchlorate. The continuum of possible effects of 

iodide-uptake inhibition caused by perchlorate exposure is only proposed and has not been 

demonstrated in humans (with the exception that in patients with hyperthyroidism doses of 200 mg 

daily or higher may reduce thyroid secretion). More importantly, the outcomes at the end of the 

continuum are not inevitable consequences of thyroid exposure. 
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In other words, except for its deliberate medical use, perchlorate has never been shown to have 

caused adverse effects in humans. Moreover, the NAS also concluded that perchlorate is not likely 

to be a carcinogen. 

In addition to the NAS conclusions, subsequent studies indicate perchlorate has not been 

demonstrated to have an adverse effect on the health of persons at environmentally relevant levels 

(Blount et al., 2006). The weight-of-evidence suggests that adverse effects do not occur following 

chronic exposures to perchlorate at doses much greater than the RfD (Tellez et al., 2005; Amitai et 

al., 2006; Braverman et al., 2006). 

Response: EPA’s final determination to regulate perchlorate is based upon the National Research 

Council’s 2005 (NRC, 2005) recommendation to use data from a human clinical study (Greer et al. 

2002) as a basis for the human health risk assessment, and as a basis for the RfD. On August 19, 

2009, EPA published a FR Notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (FR Vol. 74, No. 159, p. 41883). In this 

August 19, 2009 FR Notice, EPA requested comments on additional interpretation of data on the 

level of human health concern, perchlorate frequency of occurrence in drinking water, and the 

opportunity for health risk reduction through a national primary drinking water standard. EPA has 

considered and discusses in the FR Notice the results of current scientific literature on potential 

adverse biochemical effects, in the process of evaluating the adverse human health effects of 

perchlorate. See response to comment code 2100. 

Greer MA, Goodman G, Pleus RC, Greer SE. Health effects assessment for environmental 

perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake in 

humans. Environ Health Perspect. 2002 Sep;110(9):927-37. Erratum in: Environ Health Perspect. 

2005 Nov;113(11):A732. National Research Council (NRC). 2005. Health Implications of 

Perchlorate Ingestion. National Academies Press, Board on Environmental Studies and Toxicology, 

January, 2005, Washington, D.C. 276pp.

Commenter Name: Ellen Blaschinski, M.B.A., R.S. 

Commenter Organization: Regulatory Services Branch, Connecticut Department of Public Health 

EPA Document ID: EPA-HQ-OW-2008-0692-2091 

EPA Comment ID: 21114 

EPA Comment Code: 2100 

Comment: November 21, 2008 Water Docket Environmental Protection Agency Mailcode 2822T 

1200 Pennsylvania Ave, NW Washington DC 20460 Re: Docket 1D No. EPA-HQ-OW-2008-0692 

 The Connecticut Department of Public Health appreciates this opportunity to comment on the 

Agency's Preliminary Regulatory Determination for Perchlorate dated Oct 10, 2008. We have been 

following perchlorate closely because of its toxic properties and widespread occurrence in the 

human environment, particularly in food and water supplies impacted by local sources. It appears 

that risks from perchlorate in drinking water could be appreciable during the perinatal period in 

cases where iodine intake is marginal. This concern comes from the CDC study showing that 

perchlorate body burden is correlated with decreased thyroid hormone levels in the 31% of US 

women with low iodide intake (Blount et al. Environ Health Perspect 114:1865, 2006). Given the 

sensitive relationship between thyroid hormone and brain development, it is critical that the 

perinatal period be adequately protected from agents which can interfere with thyroid hormone 
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production. Therefore, regulting perchlorate in drinking water represents a meaningful opportunity 

for EPA to safeguard public health by setting a health-protective Maximum Contaminant Level 

(MCL) and then by requiring water supplies to regularly rest for this analyte. 

Response: Please see the response to comment ID 20975 under comment code 2100. 

Commenter Name: John P Gibbs 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0636 

EPA Comment ID: 28550 

EPA Comment Code: 2100 

Comment: My comments are in the attached file. 

John P Gibbs, MD 300 Fischer Store Road Wimberley,TX 78676 phone 512/847-2748 cell: 

512/667-0625 email jpgibbs@hughes.net 

 ENVIRONMENTAL PROTECTION AGENCY OFFICE OF WATER [EPA-HQ-OW-2009-

0297; FRL-8943-9], RIN 2040-AF08 Drinking Water: Perchlorate, Supplemental Request for 

Comments Federal Register / Vol. 74, No. 159 / Wednesday, August 19, 2009 / Notices 

Water Docket, EPA Docket Center (EPA/DC) EPA West, Room 3334, 1301 Constitution Ave., 

NW, Washington, DC. (202) 566-2426. 

Dear Sirs, 

I appreciate the opportunity to comment on the United States Environmental Protection Agency 

(U.S. EPA) Office Water regarding its request for supplemental comments. I have been very active 

with the perchlorate issue over the past 11 years. 

John P. Gibbs, MD PO Box 2948, 300 Fischer Store Road Wimberley, Texas 78676 Phone: 512-

847-2748, cell 512-667-0625 Email: jpgibbs@hughes.net 

1) The 2005 NAS REPORT 

Perchlorate is one of the most well-studied chemicals with detailed information on the mechanism 

of action, dose-response, and health effects. The 2005 NAS report was a comprehensive review of 

the science. The animal and human studies that have been published since the NAS report reduce 

the uncertainty and reinforce the NAS panel's finding that there will not be any adverse health 

effects from perchlorate at environmentally-relevant concentrations 

In using a NOEL, the NAS committee deemed its approach as conservative and health protective as 

this dose is already lower than any dose in which adverse effects occur. Furthermore, a safety factor 

of 10 is applied to the NOEL to account for the most sensitive individuals in a population, in this 

case, hypothyroid or iodine-deficient pregnant women and their developing fetuses. The NAS panel 

stated that "the NOEL value from Greer et al. (2002) is a health- protective and conservative point 

of departure is supported by...extensive human and animal data that demonstrate that there will be 

no progression to adverse effects if no inhibition of iodide uptake occurs" 
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Response: For the reasons provided in the preliminary and final determinations, EPA has found 

that perchlorate may have an adverse effect on human health. Also, see response to comment code 

2100. 

Commenter Name: John P Gibbs 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0636 

EPA Comment ID: 28554 

EPA Comment Code: 2100 

Comment: 5) CONCLUSIONS 

The 2005 NAS report remains the most credible and complete assessment on potential toxicity of 

perchlorate from environmental sources. All scientific reports issued after the NAS report (with the 

exception of Blount et al 2006) support that the RfD recommended by the NAS is protective for 

sensitive subpopulations. Setting an MCL for perchlorate in drinking water below 15 or 24 ug/L 

does not provide meaningful opportunity for improving public health. 

Response: EPA has considered the results of current scientific literature on potential adverse 

biological effects, in the process of evaluating the adverse human health effects of perchlorate. The 

Agency analyzed the additional information, and EPA has determined that a national primary 

drinking water regulation for perchlorate would present a meaningful opportunity for health risk 

reduction for persons served by public water systems, and that regulation of perchlorate in drinking 

water due to occurrence and health implications is warranted. EPA will continue to evaluate all of 

the available science related to perchlorate as the Agency develops a National Primary Drinking 

Water Regulation for perchlorate. See response to comment code 5220 for a discussion of 

alternative Health Reference Levels. 

Commenter Name: Sonia Salas 

Commenter Organization: Western Growers Association on behalf of several California 

agriculture groups 

EPA Document ID: EPA-HQ-OW-2009-0297-0652 

EPA Comment ID: 28678 

EPA Comment Code: 2100 

Comment: The NAS Report Remains the Most Comprehensive Scientific Review on the Health 

Effects of Perchlorate to Date. 

The National Academy of Sciences conducted a thorough inquiry of the perchlorate health effects 

literature in a highly professional and independent manner. The Panel's 2005 recommendations, 

based upon the best science available, continue to be validated by new scientific studies on 

perchlorate health effects and exposures. It is critically important to bear in mind that the NAS 

panel views its recommended perchlorate reference dose (RfD) as providing a large margin of safety 

because it is based on a No-Observed-Effect-Level (NOEL) -- inhibition of iodine uptake by the 

thyroid - rather than the traditional approach of starting from a No-Observed-Adverse-Effect-Level 

(NOAEL). The NOEL is the level below which exposure to a substance fails to elicit any biological 

response at all, and in the case of perchlorate is orders of magnitude below the levels at which 
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adverse effects may occur. The NAS perchlorate panel further reduced this NOEL by a factor of 10 

to account for variations in human response, leading them to conclude that their recommended RfD 

is highly health protective, even for sensitive subpopulations. 

Further downward adjustment of the RfD based on body weight and water consumption rates at 

various life stages, as contemplated in EPA's proposed alternative health reference levels, is 

needlessly duplicative and provides no additional health protection for any population. Moreover, 

EPA has not presented any scientific evidence indicating why its current perchlorate health reference 

level (15 ppb), which is based on the most sensitive sub-population (the pregnant woman/fetus), 

and which incorporates a ten-fold safety factor to account for variability in human response, is 

inadequate. 

Response: See response to comment code 5220 for a discussion of alternative Health Reference 

Levels. 

Commenter Name: Kay Brothers 

Commenter Organization: Southern Nevada Water Authority 

EPA Document ID: EPA-HQ-OW-2009-0297-0667 

EPA Comment ID: 28695 

EPA Comment Code: 2100 

Comment: The NRC perchlorate panel (2005) and the EPA agreed that the most susceptible 

population are "the fetuses of pregnant women who might have hypothyroidism or iodide 

deficiency" but also identified infants and developing children as additional "sensitive populations." 

Epidemiological data shows that at perchlorate exposures above and below the EPA's Reference 

Dose (RfD) for perchlorate, no adverse health effects were documented in adults and children 

exposed chronically to perchlorate via drinking water (Crump and Gibbs 2005; Tellez, Chacon et al. 

2005; Amitai, Winston et al. 2007). 

Response: See response to comment code 2100 and today’s Federal Register notice for a discussion 

of EPA’s finding of possible adverse health effects. 

Commenter Name: Robert E. Brackett 

Commenter Organization: Grocery Manufacturers Association (GMA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0413 

EPA Comment ID: 28707 

EPA Comment Code: 2100 

Comment: Second, EPA must make it clear to the public that the starting point for determining the 

Reference Dose (RfD), a safe daily exposure level for perchlorate, is a biological effect that is not 

itself harmful, and does not indicate any harm will occur. In 2005, an expert panel of the National 

Research Council (NRC) reviewed the evidence and determined a reference dose (RfD) for 

perchlorate based on a No Observed Effect Level (NOEL) in a study in human subjects. The 

NOEL is the lowest observed dose at which no biologically significant changes are observed, and it 

is a lower does than the customary starting point for an RfD, the No Observed Adverse Effect 

Level (NOAEL), the dose at which no adverse effects are observed. Humans and animals have 

built-in, compensatory mechanisms that assure their survival over a wide range of complex and 

continually changing challenges. Biological changes that are part of these normal compensatory 
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mechanisms are considered adaptive, not adverse. The NRC experts specifically articulated that extra 

measure of protection inherent in their use of the NOEL. In addition, they used a safety factor of 10 

to account for any variations in sensitivity within the population potentially at risk, hypothyroid or 

iodine deficient pregnant women and developing fetuses. The NRC approach assures that, even if 

the sensitive population were to experience an exposure as high as the RfD there is a high degree of 

confidence that no adverse effects will occur. 

Response: EPA believes the NRC appropriately based the RfD on iodide uptake inhibition to the 

thyroid, for the reasons discussed in its report. EPA notes that the data underlying the definition of 

iodide uptake inhibition as a precursor effect and the relationship of iodide uptake inhibition to the 

continuum of adverse outcomes reflects an understanding of effects in adults; it may not reflect the 

relationship of the precursor event to adverse outcomes in neonates and infants, who may not have 

iodide stores sufficient to offset the effects of reduced iodide uptake. The less resilient neonatal and 

infant system makes the exposure gap between a precursor event (iodide uptake inhibition due to 

perchlorate) and reduced T3/T4 levels likely to be narrower than for adults, and in fact, the 

distinction between the two may be blurred for the very young (Greer et al., 2002; Savin et al., 2003; 

van den Hove et al., 1999). The NRC noted that, “[T]he minimal prolonged decrease in thyroid 

hormone production that would be associated with adverse health effects is not known; any 

decrease is potentially more likely to have adverse effects in sensitive populations (people with 

thyroid disorders, pregnant women, fetuses, and infants) but data are not available to determine the 

magnitude of the decrease needed to cause adverse effects in those populations.” 

Commenter Name: Nsedu O. Witherspoon 

Commenter Organization: Children's Environmental Health Network 

EPA Document ID: EPA-HQ-OW-2009-0297-0674 

EPA Comment ID: 28740 

EPA Comment Code: 2100 

Comment: Moreover, a 1 ppb or lower MCL is supported by the most recent comprehensive 

studies, and these should be central to EPA’s analysis. The industry-supported Greer study, which 

serves as the basis for EPA’s current reference dose as well as California's current 6 ppb standard, 

consisted of a 14-day study of 37 healthy adults. In more recent years, Blount et al analyzed a 

nationally representative sample of 2299 U.S. residents, and they have documented anti- thyroid 

effects in a large population of women exposed to perchlorate at concentrations far lower than 

levels previously shown to have such effects. This study and subsequent data clearly justify 

promulgation of an even more protective MCL. It should be noted that California's Office of 

Environmental Health Hazard Assessment is in the process of reevaluating its Public Health Goal, 

on which the state MCL is based. 

Response: See response to comment code 5220 for a discussion of alternative Health Reference 

Levels and response to comment code ID 28936 under comment code 2100 for a discussion of the 

Blount et al study. EPA will conduct further analysis in developing a proposed MCL and MCLG for 

perchlorate. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28794 
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EPA Comment Code: 2100 

Comment: A reference dose (RfD) is an estimate of the daily exposure to an agent over a full 

lifetime that is "likely to be without an appreciable risk of deleterious effects" for the human 

population, including sensitive subgroups.[FN13: EPA Integrated Risk Information System (IRIS) 

Glossary of terms. http://www.epa.gov/ncea/iris/help_gloss.htm#r] The RfD is not an 

enforceable regulatory standard; it can be used with exposure information to set clean up levels. In 

2005, the National Research Council (NRC) of the National Academies of Science recommended an 

RfD for daily intake of perchlorate that it considered to be an acceptable level of exposure of 0.7 

ug/kg/day.[FN14: NRC. 2005. Health Implications of Perchlorate Ingestion. National Research 

Council of the National Academies. National Academies Press, Washington, D.C.] EPA adopted 

this RfD and posted on its public database, the Integrated Risk Information System (IRIS) in 

February 2005.[FN15: EPA IRIS assessment of perchlorate. 

http://www.epa.gov/NCEA/iris/subst/1007.htm] While IRIS values are not regulations per se, 

they are used by both state and federal regulators and by the international community for a range of 

environmental health regulation and management purposes. For example, the information can be 

used in combination with exposure data to set cleanup levels at hazardous waste sites, or to set 

exposure standards for air, water, soil, and food. Thus, the accuracy, credibility, and timeliness of 

IRIS assessments have real world consequences for human health. 

In simple terms, the HRL is the maximum contamination level of perchlorate that could be in 

drinking water, and still keep daily human consumption levels from exceeding the RfD of 0.7 

ug/kg/day. It is not an enforceable standard. EPA reports that for pregnant women, exposure to 

perchlorate from food is 0.263 ug/kg/day at the 90th percentile (based on data from a national food 

survey), representing nearly 38% of the RfD, thus leaving an RSC (Relative Source Contribution) for 

water of 62%.[FN16: 73 Fed Reg at 60276] This is equivalent to 0.437 ug/kg/day from water, 

assuming an average body weight of 70 kg, and a daily water consumption of 2 L (90th percentile 

adult water consumption). That is, 0.437 ug x 70 kg body wt. = 30.6 ug perchlorate in 2 liters (the 

daily consumption amount). This is 15 ug/L, or 15 ppb, the originally proposed HRL. 

The RfD for perchlorate and perchlorate salts of 0.7 ug/kg body weight/day is based on a human 

volunteer study, Greer et al, 2002.[FN17: Greer, M.A., Goodman, G., Pleuss, R.C., Greer, S.E. 2002. 

Health effect assessment for environmental perchlorate contamination: The dose response for 

inhibition of thyroidal radioiodide uptake in humans. Environ. Health Perspect. 110:927-937. 

Docket HQ- OW-2009-0297 NRDC supplemental comments on perchlorate] The RfD is for oral 

exposure, including food and water, and is based on radioactive iodide uptake inhibition (RAIU) in 

the thyroid as the critical effect. The IRIS assessment of perchlorate explains that "The point of 

departure is based on a non- statistically significant mean 1.8% (standard error of the mean 8.3%) 

decline in RAIU in healthy adults following two weeks exposure to a daily perchlorate dose of 0.7 

ug/kg/day. An intraspecies uncertainty factor of 10 is applied to protect the most sensitive 

population, the fetuses of pregnant women who might have hypothyroidism or iodide deficiency. 

Dose is given as perchlorate anion."[FN18: EPA. IRIS database. Perchlorate and perchlorate salts. 

http://www.epa.gov/ncea/iris/subst/1007.htm#revhis] 

The RfD adopted by EPA has been widely criticized as inadequately protective by state scientific 

experts[FN19: Ginsberg G and D Rice. The NAS perchlorate review: questions remain about the 

perchlorate RfD. Environ Health Perspect. 2005 Sept; 113(9):1117-9. Erratum in: Environ Health 

Perspect. 2005 Nov; 113(11):A732.] and by EPA's own Children's Health Protection Advisory 
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Committee,[FN20: Letter from Melanie Marty to Administrator Johnson regarding Preliminary 

Regulatory Determination on Perchlorate (November 3, 2008, PDF) 

http://yosemite.epa.gov/ochp/ochpweb.nsf/content/perchlorateletter.htm/$file/Per 

chlorateLetter.pdf] and no longer reflects the best available data.[FN21: EN Pearce, AM. Leung, BC 

Blount, HR Bazrafshan, X He, S Pino, L Valentin-Blasini, and LE Braverman, 2007. Breast milk 

iodine and perchlorate concentrations in lactating Boston-area women. J Clin Endocrinol Metab. 

92(5):1673-7.] [FN22: Letter from Melanie Marty to Administrator Johnson regarding Preliminary 

Regulatory Determination on Perchlorate (November 3, 2008, PDF) 

http://yosemite.epa.gov/ochp/ochpweb.nsf/content/perchlorateletter.htm/$file/PerchlorateLetter

.pdf] 

Response: Please see the response to comment ID 28818 under comment code 2100. 

 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0227 

EPA Comment ID: 28818 

EPA Comment Code: 2100 

Comment: Acronyms: BAF: Background Adjusting Factor BW: Body weight of an adult (70Kg) 

DW: Drinking-Water DWL: Daily Drinking-Water Consumption in litres (2 l) GREER_NOEL: 

Greer 2002 NOEL(7ug/kg -day) NAS: National Academy of Sciences NOEL: Non Adverse Effect 

Level MCL: Maximum Contaminant Level OIG: EPA's Office of Inspection General PEC: 

Perchlorate Equivalent Concentration PEC-NOEL: Perchlorate Equivalent Concentration NOEL 

PEC-PHG : Perchlorate Equivalent Concentration PHG PHG: Public Health Goal RfD: Reference 

dose RSC: Relative Source Contribution SPEC: Serum Perchlorate Equivalent Concentration RAIU: 

Radioactive Iodine Uptake TGL: Total Urinary Goitrogen Load expressed in PEC: [Perchlorate] + 

[nitrate/150] + [thiocyanate/8.8] TH: thyroid Hormone UF: Uncertainty Factor UPEC: Urinary 

Perchlorate Equivalent Concentration 

Executive Summary 

In evaluating the risks posed by perchlorate and the value of regulation through establishment of an 

MCL, EPA is relying on information derived from a flawed analysis of the impacts of perchlorate 

exposure. There are two primary factors that have significantly impacted the perchlorate risk 

assessment, and could explain the omissions and contradictions mentioned further below. 

First, the NOEL (Non Observed Effect Level) found in the Greer 2002 study from which the 

perchlorate RfD is derived, did not take into account existing background effect. The root of this 

omission could lie in the fact that a qualitative observational study, which takes into account 

background levels and is by far the most common human epidemiological study used in evaluating 

exposure risks to humans, was not performed or relied on in analyzing the impact of perchlorate in 

this instance. Instead, the Greer study was an experimental study on humans, which did not take 

into account background effects and thus significantly overstates the impact of perchlorate on 

human health. Therefore, the NOEL found by the Greer study is not accurate, and should not be 

relied upon to either regulate perchlorate or establish an RfD. 
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Response: EPA respectfully disagrees with the commenter. The RfD, which is derived from the 

NOEL, is an estimate (with uncertainty spanning perhaps an order of magnitude) of a daily oral 

exposure to the human population that is likely to be without an appreciable risk of deleterious 

effects during a lifetime. The RfD, based on the assumption that thresholds exist for certain toxic 

effects of chemicals, represents the drinking water perchlorate exposure plus an incremental 

additional exposure of perchlorate from either water or food which could trigger iodine uptake 

inhibition, with a 10X safety factor applied. The NRC recommended that data from the Greer et al. 

(2002) human clinical study be used as the basis for deriving a perchlorate reference dose (RfD) 

(NRC 2005), and also noted that the results of this study were supported by those of other human 

studies. From this Greer et al. (2002) human clinical study, the statistical no observed effect level 

(NOEL) for the perchlorate-induced inhibition of thyroid iodide uptake was determined to be 7.0 

ug/kg (a corresponding iodide uptake inhibition of 1.8%). The NRC concluded that the most health 

protective and scientifically valid approach to deriving a reference dose for perchlorate was to base 

the perchlorate RfD on the precursor event of inhibition of iodide uptake by the thyroid, which 

would precede any more severe adverse health effects of perchlorate exposure in humans. In this 

case, the NRC used a precursor to adverse thyroid effects to establish a level at which no adverse 

effects would be anticipated in exposed populations. This approach is consistent with the Agency’s 

policy on the use of precursor events when appropriate in establishing the critical effect upon which 

an RfD is based (U.S. EPA, 2002). The NRC recommended that EPA apply an uncertainty factor of 

10 to this NOEL of 7.0 ug/kg for the perchlorate-induced inhibition of thyroid iodide uptake, to 

account for differences in sensitivity between healthy adults and the most sensitive sub-population 

(fetuses of pregnant women who might have hypothyroidism or iodide deficiency). The NRC 

viewed the recommended uncertainty factor of 10 as conservative and protective of health, given 

that the NOEL is based on a non-adverse effect (iodide uptake inhibition). NRC recommended that 

using a non-adverse effect that is upstream of the adverse effect represents a more conservative, 

health-protective approach to the risk assessment for perchlorate, noting that the purpose of the 10-

fold uncertainty factor is to protect sensitive subpopulations in the face of uncertainty regarding 

their relative sensitivity to perchlorate exposure. EPA has adopted the NRC’s recommendations in 

its “Integrated Risk Information System” (USEPA, 2005), resulting in an RfD of 0.7 ug/kg/day, 

which was derived by applying a 10-fold uncertainty factor to the NOEL of 7.0 ug/kg/day. EPA 

used the best available peer-reviewed science, and the Agency has determined to regulate perchlorate 

in drinking water. EPA will continue to evaluate scientific studies of perchlorate health effects as 

part of the perchlorate rulemaking process. Greer MA, Goodman G, Pleus RC, Greer SE. Environ 

Health Perspect. 2002 Sep;110(9):927-37. National Research Council (NRC). 2005. Health 

Implications of Perchlorate Ingestion. National Academies Press, Board on Environmental Studies 

and Toxicology, January, 2005, Washington, D.C. 276pp. USEPA. 2002. A review of the reference 

dose and reference concentration processes. Risk Assessment Forum, Washington, DC; 

EPA/630/P–02/0002F. USEPA. 2005. ‘‘Integrated Risk Information System (IRIS), Perchlorate 

and Perchlorate Salts.’’ February 2005. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0227 

EPA Comment ID: 28820 

EPA Comment Code: 2100 

Comment: 1.1. Introduction 
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The perchlorate NAS (National Academy of Sciences) RfD (Reference Dose) of 0.7ug//kg-day is 

based on the Greer 2002 dose response experimental clinical study[FN1: Greer MA, Goodman G, 

Pleus RC, Greer SE, 2002. Health Effects Assessment for Environmental Perchlorate 

Contamination: The Dose Response for Inhibition of Thyroidal Radioiodine Uptake in Humans. 

Environ. Health Perspective, 110(9):927-937.]. However the NOEL (Non Observed Effect Level) 

found in the Greer experimental longitudinal study did not take into account existing background 

effects, and therefore the Greer NOEL is not an accurate reflection of the NOEL for perchlorate. 

NAS did not add this background level to the Greer NOEL level in its evaluation of perchlorate. 

Similarly, EPA’s OIG did not do so in its December 2008 study [FN2: Office of Inspector General 

Scientific Analysis of Perchlorate, Assignment No. 2008-0010, December 30, 2008.]. The 

consequences of this omission are significant as discussed below. 

Response: Please see the response to comment ID 28818 under comment code 2100. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28896 

EPA Comment Code: 2100 

Comment: As a reminder, Intertox provided comments to these studies in a 2008 submission; these 

comments are located in the EPA docket (Intertox, 2008). Intertox also provided comments to the 

Draft OIG report (Intertox, 2009). Nonetheless, these studies are summarized below. EPA has also 

posted several additional documents to the docket that require additional context. 

A. The 2009 FR Notice Docket 

The EPA Docket for this Notice (Docket ID No. EPA-HQ-OW-2009-0297) includes a number of 

documents including a commentary that provides criticism of the NRC expert panel's conclusions 

on perchlorate, but does not provide new scientific data from which to base a regulatory 

determination (Ginsberg and Rice, 2005). To provide a transparent compendium of available 

information, if the Agency provides or uses any commentaries, it should consider all commentaries. 

For example, a response to Ginsberg and Rice (2005) was published in the same journal. This 

response was co-authored by the NRC perchlorate panel chair and three other members from the 

18-member panel and provides point-by-point science based rebuttals to why the Ginsberg and Rice 

(2005) assertions are incorrect. The response authors conclude by stating that the NRCrecommended RfD "provides a wide margin of safety for all subjects of all ages" (Johnston, et al., 

2005). We request that EPA add this response to the docket. 

Response: EPA will continue to evaluate the best available science related to perchlorate as the 

Agency develops a National Primary Drinking Water Regulation for perchlorate. The Johnson, et. 

al., commentary has been reviewed by EPA and added to the docket. Also, see response to 

comment code 2100. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 
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EPA Comment ID: 28901 

EPA Comment Code: 2100 

Comment: Greer et al. (2002) 

As noted above and briefly reiterated here, the mechanism of action (MOA) of perchlorate in 

humans is the inhibition of iodide uptake (IUI). The MOA has been reviewed by numerous 

authoritative bodies (NRC, EPA, ATSDR, etc.) who have concluded that it is not adverse. Iodide 

uptake is mediated by the NIS in the thyroid follicular cell. Greer et al. found a level where there was 

no statistical change in IUI and therefore, no downstream effects were possible. 

That IUI is not adverse has been well-documented by NRC, EPA, New Jersey, California, and 

ATSDR. Much is documented about exposures to perchlorate at environmentally relevant doses up 

to therapeutic doses, the amount of IUI these doses cause, and the lack of downstream effects with 

environmentally relevant doses. For example, many studies demonstrate a statistically significant 

IUI, but no change in thyroid hormones for weeks or months (Greer et al., 2002; Braverman et al., 

2005; Lawrence et al., 2000 and 2001; etc.). Moreover, the literature regarding perchlorate at 

therapeutic doses demonstrates the effect of IUI and changes in hormones. The NRC committee 

members unanimously stated that transient changes in thyroid hormones are not adverse and 

prolonged changes in thyroid hormones must occur for a person to become hypothyroid. 

Some have argued that the study population of the Greer Study was too small to exhibit statistical 

significance of small changes in IUI particularly with the variability reported. It is important to note 

that decisions regarding statistical power and sample size were conducted a priori, in accordance 

with standard experimental design. These were stated and agreed upon by the researchers and EPA. 

The questions by some about variability have been raised a posteriori, after the results are known. 

Based on all the information available when the experiment was designed, the sample sizes in the 

Greer Study were sufficient. Notably, with a dose of 0.02 mg/kg-d, a 16% IUI (24-hr value) was 

statistically significant. 

Regarding the variability of the low dose group, IUI from "background" (as noted above in Figure 3) 

perchlorate, nitrate, thiocyanate, and other agents found in the diet and drinking water were not 

controlled. This likely explains a significant proportion of daily interpersonal RAIU changes. 

Furthermore, 1) variability in RAIU for the low dose group was not different from RAIU for other 

dose groups, 2) all volunteers had normal baseline RAIU values when compared to the literature, 

and 3) when baseline RAIU is low, small absolute changes will appear large as relative RAIU, which 

is a mathematical, not physiologic, phenomenon. 

In a dose-response study, one dose group should not be taken in isolation. The best way to evaluate 

the low-dose variability in RAIU is to examine all data generated by the study. Simple inspection of 

the data show a decrease in RAIU change with increasing dose-IUI occurred in a classic and 

unequivocal dose- response manner. Additionally, the No Effect Level (NEL) using linear 

regression of all relevant RAIU clinical data was 6 ug/kg-d for 24 hours, which was similar the 

NOEL of 7 ug/kg-d. Considering the data from Lawrence et al. (2001) which demonstrated a higher 

dose of perchlorate (approximately 40 ug/kg-d assuming 3 mg/d for a 70 kg person) with a nonstatistically significant decrease in RAIU (as well as no corresponding change in thyroid hormones) 

strengthens this understanding. 
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Response: See response to comment code 2100. EPA will continue to evaluate all of the available 

science related to perchlorate as the Agency develops a National Primary Drinking Water Regulation 

for perchlorate. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group (EWG) 

EPA Document ID: EPA-HQ-OW-2009-0297-0499 

EPA Comment ID: 28936 

EPA Comment Code: 2100 

Comment: EWG urges the agency to take the results from this CDC study into account and revise 

the current RfD to reflect these findings. In written responses to questions for the record from the 

House Committee on Energy and Commerce dated from 2007 (attached), Dr. James Pirkle, Deputy 

Director for Science at the National Center for Environmental Health and coauthor of the study, 

had the following comments regarding the study results: "We do not think confirmatory analysis is 

necessary to validate Blount's analysis of the NHANES data. Although we understand that 

conclusions of causality can rarely be drawn based upon a single study, when viewed within the 

context of the available clinical literature, the findings of the Blount study are consistent with 

causality" (Attached). In addition, an independent analysis of the NHANES data by scientists who 

work for California's Office of Environmental Health Hazard Assessment confirmed CDC's 

findings (Steinmaus et al 2007). Given the issues with the data in the Greer study and the strengths 

of the Blount study, the agency should place greater weight on the results from the Blount study in 

its determination. 

Response: In the October 10, 2008 FR Notice requesting public comments on its preliminary 

determination not to regulate perchlorate in drinking water (FR Vol. 73, No. 198, p. 60266), EPA 

considered and discusses the results of the Greer et al. (2002), and Blount et al. (2006, 2007) studies, 

in the process of evaluating the adverse health effects of perchlorate. Blount et al., (2006) published 

a study in the journal “Environmental Health Perspectives” examining the relationship between 

urinary levels of perchlorate and blood serum levels of TSH and total T4 in 2,299 men and women 

(ages 12 years and older) who participated in CDC’s 2001–2002 NHANES. Blount et al. (2006) 

evaluated perchlorate along with a number of covariates known or likely to be associated with 

thyroid hormone levels, to assess the relationship between perchlorate and these hormones. The 

Blount et al. (2006) study found that perchlorate exposure was a statistically significant predictor of 

thyroid hormones in women, but not in men. For women with urinary iodide levels less than 100 

ug/L, the researchers found that urinary perchlorate was associated with a decrease in T4 levels and 

an increase in TSH levels. For women with urinary iodide levels greater than or equal to 100 ug/L, 

the researchers found that perchlorate was a significant positive predictor of TSH, but not a 

predictor of T4. Their observations that adverse thyroid hormone effects were found in women 

whose urinary iodine was below 100 ug/L is suggestive of a partial study population iodine 

deficiency status. Blount et al. (2006) noted several limitations of their study and recommended that 

their findings be affirmed in other large studies focusing on women with low urine iodide levels. 

Since their study was cross-sectional in design, it also cannot be concluded whether or not the 

association between perchlorate and thyroid hormone levels is causal, or is mediated by some other 

correlate of both, although the relationship between urine perchlorate and total TSH and T4 levels 

persisted after statistical adjustments for some additional covariates known to predict thyroid 

hormone levels. EPA has evaluated this data as part of the regulatory determination EPA will 
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continue to evaluate new scientific information on the health effects of perchlorate as the Agency 

develops the proposed perchlorate drinking water regulation. 

Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell KL. Urinary perchlorate and thyroid 

hormone levels in adolescent and adult men and women living in the United States. Environ Health 

Perspect. 2006 Dec;114(12):1865-71. 

Blount BC, Valentin-Blasini L, Osterloh JD, Mauldin JP, Pirkle JL. Perchlorate exposure of the US 

Population, 2001-2002. J Expo Sci Environ Epidemiol. 2007 Jul;17(4):400-7. Epub 2006 Oct 18. 

Greer MA, Goodman G, Pleus RC, Greer SE. Health effects assessment for environmental 

perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake in 

humans. Environ Health Perspect. 2002 Sep;110(9):927-37. Erratum in: Environ Health Perspect. 

2005 Nov;113(11):A732. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 29079 

EPA Comment Code: 2100 

Comment: EPA's preliminary determination includes imprecise language that bears clarification: 

Perchlorate interacts with the sodium iodide symporter, reducing iodine uptake into the thyroid 

gland and, at sufficiently high doses, the amount of T4 produced and available for release into 

circulation. Sustained changes in thyroid hormone secretion can result in hypothyroidism. (p. 60275; 

emphasis added) 

[Text Box: The NAS concluded that perchlorate will not cause adverse effects under consideration 

in this determination. The NAS findings are consistent, as well as the overwhelming majority of the 

large body of available peer-reviewed science on perchlorate.] 

The "sufficiently high doses" that EPA refers to are orders of magnitude higher, approximately 0.4 

mg/kg-d (approximately 19,000 ppb)[FN2: See, NAS, at 171-172 (pdf version) ("...a sustained 

exposure at more than 0.4 mg/kg per day would most likely be required to cause a sufficience 

decline in iodide uptake and thyroid hormone production to result in adverse health effects in 

normal adults. That estimate is based on clinical studies and studies of long-term treatment of 

patients who had hyperthyroidism.]. These levels have never been reported in public drinking water 

systems. According to the NAS report, even these levels do not inevitably lead to adverse effects. 

The NAS independently evaluated the science and its conclusions and recommendations are 

published in the report Health Implications of Perchlorate Ingestion (2005). The NAS report 

recommended an RfD of 0.7 ug/kg-d based on a No Observed Effect Level (NOEL), or the dose at 

which no effects occur, adverse or otherwise (NAS, 2005). One of the critical studies that served as 

the basis for this RfD was the study by Greer et al. (2002) which demonstrated that there was no 

inhibition of iodide uptake by the thyroid at a dose of 7 ug/kg-d. Some have argued that the low 

dose group contained only seven subjects; however the NAS correctly dismissed this assertion, 

pointing out that there were four doses provided across 37 subjects. Importantly, the NAS also 
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noted that it did not examine Greer in isolation. According to the NAS report, the findings in Greer 

are supported by other clinical studies, occupational and environmental epidemiologic studies, and 

studies of long-term perchlorate administration to patients with hyperthyroidism. 

Further, the NAS states with emphasis, 

"Inhibition of iodide uptake by the thyroid clearly is not an adverse effect; however if it does not 

occur, there is no progression to adverse health effects." The committee views its recommendation 

to use [IUI] by the thyroid as the basis of the perchlorate risk assessment to be the most healthprotective and scientifically valid approach (NAS, 2005). 

In using a NOEL, the NAS committee adopted a notably conservative, health- protective approach. 

This dose is already lower than any dose in which adverse effects occur; an additional safety factor 

of 10 is applied to the already conservative NOEL. The NAS was acting to ensure protection for the 

most sensitive individuals in a population, in this case, hypothyroid or iodine- deficient pregnant 

women and their developing fetuses. Importantly, the NAS panel did consider other sensitive 

populations besides pregnant women and their fetuses. They also considered the potential effect on 

infants, developing children, people who have compromised thyroid function, and people who are 

iodide-deficient. The NAS panel stated that using a NOEL as the point of departure is a more 

conservative and health-protective approach than EPA's customary approach of using the adverse 

effect (NAS, 2005). 

The NAS panel also took time to distinguish between a No Observable Adverse Effect Level 

(NOAEL) from a NOEL. The experts observed that there was confusion between the two and 

clarified that the NOAEL is based upon an adverse effect, whereas the NOEL is based upon a dose 

at which no effect occurs, adverse or otherwise. (NAS, 2005). 

EPA adopted the RfD recommended by the NAS and confirmed that it was conservatively based on 

the NOEL, not the NOAEL. EPA should clarify its finding as to the potential adverse effects of 

perchlorate to bring the final determination into alignment with its own NAS-based reference dose. 

In sum: perchlorate will not cause adverse effects at levels under consideration in this determination. 

This conclusion reflects the best available scientific findings, including the NAS report and the 

overwhelming majority of the large body of available peer-reviewed science on perchlorate. 

Response: Please see the response to comment ID 21094 under comment code 2100.
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EPA Comment Code: 2110 Regulatory determination based upon the alreadyestablished RfD 

Individual Comments 

Commenter Name: Michael Dourson 

Commenter Organization: Toxicology Excellence for Risk Assessment (TERA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0637 

EPA Comment ID: 28493 

EPA Comment Code: 2110 

Comment: Our primary concerns relate to the current EPA RfD of 0.0007 mg/kg-day found on 

EPA's Integrated Risk Information System (IRIS), since new data have shown this value to be out of 

date. 

Concern: EPA acknowledges in its Federal Register notice that critically important data on pregnant 

women and their offspring have become available since the time of the development of the EPA 

RfD in 2005 (EPA, 2008), but then fails to cite a prospective epidemiology study by Tellez et al. 

(2005) that analyzed the results of differing perchlorate exposures in pregnant mothers and their 

newborns. As a basis of an RfD, Tellez et al. (2005) is superior to the study used as the basis of the 

current RfD, that is Greer et al. (2002), since the Tellez et al. (2005) study is on the sensitive 

populations of interest (pregnant women and their babies). As a basis of an RfD, Tellez et al. (2005) 

is vastly superior to the ecological epidemiology study of Blount et al. (2006, 2007), since Tellez et al. 

(2005) measured perchlorate exposure in the individuals on which the effects of concern were 

monitored. 

Recommendation: EPA needs to reconsideration its existing RfD on the basis of the Tellez et al. 

(2005) epidemiology study in pregnant women and their babies. This reconsideration is consistent 

with recommendations of the NAS (2005) on page 69 of its report. 

Concern: NAS (2005, pages 9 and 112) admits that it did not follow EPA's traditional RfD method 

when it developed their value. Since EPA adopted the NAS RfD, the inescapable conclusion is that 

EPA did not follow it own RfD method either. More importantly, lack of adherence to EPA’s 

methods will encourage others to do so as well, resulting in a potpourri of values with little 

resemblance to those that already exist on EPA's Integrated Risk Information System (IRIS) or 

elsewhere. 

Recommendation: Recalculate the existing perchlorate RfD using EPA's published methods. 

See the attached file for details. Reviewed using developmental reserve. [See PDF Docket ID EPAHQ-OW-2009-0297-0637; Note that this attachment is identical to Docket ID EPA-HQ-OW-2008-

0692-1562; responses to this comment are provided through Docket ID EPA-HQ-OW-2008-0692-

1562.] 

Response: See response to comment ID 28863 under comment code 2110. 
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EPA will consider the best available peer reviewed data in developing an NPDWR for perchlorate, 

including the data from the Tellez study. 

Commenter Name: Jonathan Borak 

Commenter Organization: Yale School of Medicine 

EPA Document ID: EPA-HQ-OW-2009-0297-0209 

EPA Comment ID: 28506 

EPA Comment Code: 2110 

Comment: My submitted comments are contained in the attachment. Thank you for this 

opportunity to contribute to the Agency's efforts. 

Jonathan Borak, MD, DABT, FACP, FACOEM 

Attachment 

 September 16, 2009 

Water Docket Environmental Protection Agency Mailcode: 2822T 1200 Pennsylvania Avenue, NW 

Washington, DC 20460 

Re: Docket ID No. EPA-HQ-OW-2009-0297 

Dear Sir or Madam: 

At the request of the Perchlorate Study Group, I am writing as a physician and toxicologist in 

response to your request for comments (Fed Reg 74:41883, 08/19/09) regarding EPA's perchlorate 

regulatory determination. By way of introduction, I am Clinical Professor of Epidemiology and 

Medicine at Yale School of Medicine, Director of the Yale University Interdisciplinary Risk 

Assessment Forum, and a faculty member of the Yale Occupational and Environmental Medicine 

Program. I serve as Co-Chair of the Council on Scientific Affairs of the American College of 

Occupational and Environmental Medicine (ACOEM), was Editor and Course Director of the 

ACOEM Core Curriculum in Environmental Medicine, and served as a founding member of EPA's 

National Advisory Committee to Develop Acute Exposure Guideline Levels for Hazardous 

Substances. 

1.) First and foremost, I support the Agency's decision to base its regulatory decision upon the 

current RfD, and not upon the findings of studies published since 2005 (Fed Reg 74:41892, 

08/19/09). Over the past several years, much attention has been given to findings reported by 

Blount et al. (1), who analyzed data from the CDC's 2001-2002 NHANES study and performed 

additional analyses on NHANES urine samples. 

Response: The Agency believes that the current RfD is appropriate for purposes of this regulatory 

determination. 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 
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EPA Comment ID: 28745 

EPA Comment Code: 2110 

Comment: 2. The findings of several studies conducted since 2005 suggest that the EPA- adopted 

reference dose of 0.7 ug/kg-day is a conservative and health-protective reference dose that has a 10-

fold uncertainty factor applied to the point of departure to account for differences between healthy 

adults and the most sensitive population: fetuses of pregnant women who might have 

hypothyroidism or iodide deficiency. Consequently, additional non-standard adjustments appear 

unnecessary because the health of the most sensitive sub-population (fetuses and neonates) has 

already been considered. Application of an appropriately calculated relative source contribution 

(RSC) term, as was conducted during development of the December 2008 Health Advisory (HA), 

appears adequate and appropriate. 

Response: EPA believes that the RfD indicated by the NAS is appropriate. EPA has not yet 

determined how best to develop the MCLG for perchlorate. EPA plans to seek comments on its 

development of its proposed regulation, including the MCLG, as required by the SDWA. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection (MassDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0495 

EPA Comment ID: 28863 

EPA Comment Code: 2110 

Comment: 5) Although the HRL of 2 ppb recommended above is numerically similar to the 

maximum contaminant level adopted by MassDEP and protective of the sensitive segment of the 

population, the RfDs used by the two agencies as the bases to derive the drinking water levels are 

different. MassDEP concluded that the National Research Council's (NRC) RfD is not protective of 

public health (Zewdie et al. 2009). Although uncertain, the EPA's modified PBPK analysis presented 

in Table 1 for a 7-day-old healthy infant supports this position. In this analysis, the infant gets about 

3 times the maternal dose through breast milk at the dose equal to the point-of-departure (POD) in 

the NRC RfD derivation. This translates to a 7-day infant receiving about 20 ug/kg/day (0.02 

mg/kg/d) dose of perchlorate through breast milk from a mother ingesting 7 ug/kg/day. This dose 

level is equivalent to the exposure level that resulted in significant inhibition (17 %) of iodide uptake 

in healthy adults in the Greer et al. (2002) study, suggesting that the factor of 10 applied to the POD 

by the NRC to protect sensitive individuals is insufficient. An additional uncertainty factor is 

required to extrapolate from LOAEL to NOAEL as 0.02 mg/kg/day is an effect level. Efforts to 

determine populations at risk based on the NRC RfD will yield significant underestimates of those 

at risk. MassDEP can support EPA's decision to not re-evaluate the NRC RfD at this time, if EPA 

adopts an HRL of 2 ppb or lower. 

Response: With regards to conclusions of the NRC panel on the effects of perchlorate exposure, 

EPA believes the NRC appropriately based the RfD on iodide uptake inhibition to the thyroid, for 

the reasons discussed in its report. The NRC (2005) identified "the fetus of pregnant women who 

might have hypothyroidism or iodide deficiency" as "the most sensitive population," but also 

identified infants and developing children as additional "sensitive populations." It is important to 

consider that the source of the perchlorate in breast milk is probably due to a much greater extent to 

the greater prevalence of perchlorate in food, than due to comparatively lesser prevalence of 

perchlorate in drinking water. The NRC recommended that EPA apply an uncertainty factor of 10 
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to the NOEL of 7.0 ug/kg for the perchlorate-induced inhibition of thyroid iodide uptake, to 

account for differences in sensitivity between healthy adults and the most sensitive sub-population, 

consisting of fetuses of pregnant women who might have hypothyroidism or iodide deficiency. 

Iodide uptake inhibition has been identified in the literature as an area of concern in connection with 

increasing the risk of neurodevelopmental impairment in fetuses of high-risk mothers. The NRC 

viewed the recommended uncertainty factor of 10 as conservative and protective of health, given 

that the NOEL is based on a non-adverse effect (iodide uptake inhibition) which precedes the 

adverse effect in a continuum of possible adverse biological effects of perchlorate exposure. NRC 

recommended that using a non-adverse effect that is upstream of the adverse effect represents a 

more conservative, health-protective approach to the risk assessment for perchlorate, noting that the 

purpose of the 10-fold uncertainty factor is to protect sensitive subpopulations in the face of 

uncertainty regarding their relative sensitivity to perchlorate exposure. EPA has adopted the NRC’s 

recommendations in its “Integrated Risk Information System” (IRIS) (USEPA 2005), resulting in an 

RfD of 0.7 ug/kg/day, which was derived by applying a 10-fold (10x) uncertainty factor to the 

NOEL of 7.0 ug/kg/day. EPA used the best available peer-reviewed science, and the Agency has 

determined to regulate perchlorate in drinking water. EPA will be reevaluating this issue as part of 

the perchlorate rulemaking. Greer MA, Goodman G, Pleus RC, Greer SE. Health effects assessment 

for environmental perchlorate contamination: the dose response for inhibition of thyroidal 

radioiodine uptake in humans. Environ Health Perspect. 2002 Sep;110(9):927-37. Erratum in: 

Environ Health Perspect. 2005 Nov;113(11):A732. National Research Council (NRC). 2005. Health 

Implications of Perchlorate Ingestion. National Academies Press, Board on Environmental Studies 

and Toxicology, January, 2005, Washington, D.C. 276pp. USEPA. 2005. "Integrated Risk 

Information System (IRIS), Perchlorate and Perchlorate Salts." February 2005. Available on the 

Internet at: http:// www.epa.gov/iris/subst/1007.htm. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28895 

EPA Comment Code: 2110 

Comment: III. OTHER COMMENTS 

In Section IV of the Notice, EPA discusses its consideration of studies published since EPA 

adopted the NRC RfD for perchlorate. The Notice states: 

EPA's preliminary regulatory determination is based on NRC's (NRC, 2005) recommendation to use 

data from the Greer et al. (2002) study as the basis for the perchlorate RfD/risk assessment. Since 

the publication of the NRC report, researchers have investigated perchlorate occurrence in humans 

by analyzing for perchlorate in urine and breast milk-such biomonitoring data has the potential to 

better inform EPA's analysis of exposure to perchlorate through food and water and to provide 

insight into the possible interactions of other physiologic conditions (e.g., iodine deficiency) with 

perchlorate ingestion. EPA's preliminary regulatory determination described the consideration of 

these studies, many of which were published after the NRC report (including, but not limited to, 

Blount et al. (2006 and 2007), Steinmaus et al. (2007), and Amitai et al. (2007)). 

EPA's conclusion to this section is: 
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EPA agrees that additional important data have become available since the RfD was derived in 2005. 

However, EPA has evaluated the new data and has decided to make the regulatory determination 

based upon the current RfD. 

The weight-of-scientific evidence supports this EPA conclusion. 

Response: EPA believes that the RfD indicated by the NRC is appropriate. As discussed in this FR 

notice, EPA has decided the model does not directly bear on the current decision regarding the need 

for a NPDWR for perchlorate. EPA is continuing to evaluate whether the model could be used in 

setting a NPDWR for perchlorate. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group (EWG) 

EPA Document ID: EPA-HQ-OW-2009-0297-0499 

EPA Comment ID: 28927 

EPA Comment Code: 2110 

Comment: - EPA must modify the RfD that is the basis for its standard setting to include a 

substantial body of peer-reviewed science published since 2002, including two large, high quality 

epidemiologic studies from the CDC (Blount et al 2006a, Blount et al 2006b). In addition to these 

new studies, peer reviewed analyses of the study that forms the basis for the current RfD (Greer 

2002) have revealed fatal flaws with this work. A study with such fundamental and well-documented 

shortcomings cannot be used as the basis to determine national safety standards for exposure to this 

potent thyroid toxin. 

Response: See response to comment ID 28863 under comment code 2110. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 29077 

EPA Comment Code: 2110 

Comment: EPA is justified in making a regulatory determination based upon the current Reference 

Dose (RfD), which includes a 10-fold uncertainty factor (UF) to account for sensitive life stages; 

further reductions for sensitive life stages are duplicative and not scientifically justified. Importantly, 

authoritative bodies concur that the RfD is based on a No Observed Effect Level (NOEL), which is 

a more conservative approach than EPA's traditional use of a No Observed Adverse Effect Level 

(NOAEL). In establishing the threshold for IUI-which is defined by the National Academy of 

Sciences as a nonadverse effect-as the point of departure, EPA has already ensured that downstream 

adverse effects due to perchlorate (which to date have not been reported in humans exposed to 

perchlorate at environmental levels) will not occur (NRC, 2005). Since much information regarding 

the perchlorate mechanism of action is known, EPA should use PBPK modeling based on the best 

science rather than the estimations in the alternative HRL calculations. 

Response: EPA believes that the RfD indicated by the NRC is appropriate. As discussed in this FR 

notice, EPA has decided the model does not directly bear on the current decision regarding the need 
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for a NPDWR for perchlorate. EPA is continuing to evaluate whether the model could be used in 

setting a NPDWR for perchlorate. 
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EPA Comment Code: 2150 EPA's decision not to seek further input from the 

NRC on issues related to perchlorate 

Response to Comment Code 2150: On October 10, 2008, EPA published a Federal Register 

notice presenting the Agency’s preliminary regulatory determination for perchlorate and supporting 

rational for this determination, in accordance with the Safe Drinking Water Act (SDWA) (Federal 

Register Vol. 73, No. 198, p. 60262). In this October 10, 2008 Federal Register notice, EPA 

determined that a national primary drinking water regulation (NPDWR) for perchlorate would not 

present a meaningful opportunity for health risk reduction for persons served by public water 

systems. On August 19, 2009, EPA published a Federal Register notice requesting supplemental 

public comments on its preliminary determination not to regulate perchlorate in drinking water 

(Federal Register Vol. 74, No. 159, p. 41883). In this August 19, 2009 Federal Register notice, EPA 

requested comments on additional interpretation of data on the level of human health concern, 

perchlorate frequency of occurrence in drinking water, the opportunity for health risk reduction 

through a national primary drinking water standard, and also requested comment on whether further 

review by the NRC would be warranted. In January of 2009, EPA announced that the Agency 

planned to seek additional input from the National Research Council (NRC) on perchlorate. The 

NRC previously studied perchlorate health implications from March, 2003 until they issued their 

report in January, 2005 (NRC 2005). EPA has compiled and evaluated additional scientific studies 

relevant to perchlorate health effects and exposure available in the scientific literature since 

publication of the 2005 NRC report. EPA also has obtained peer review and public comment on the 

Agency’s analysis of a number of these studies. The Agency currently believes that further review by 

the NRC would unnecessarily delay regulatory decision making for perchlorate. EPA also notes in 

this August 19, 2009 Federal Register notice that if the Agency were to make a final determination to 

regulate perchlorate, the Agency, in accordance with the SDWA, would seek review by the Science 

Advisory Board prior to proposal of any maximum contaminant level goal and national primary 

drinking water rule. Therefore, EPA is not, at present, planning to request additional NRC review of 

issues related to perchlorate. 

Individual Comments 

Commenter Name: Julie L. Heckman 

Commenter Organization: American Pyrotechnics Association (APA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0522 

EPA Comment ID: 28492 

EPA Comment Code: 2150 

Comment: EPA's Commitment to Use Sound Science 

In January of this year, EPA announced that it would reevaluate the science regarding perchlorate's 

potential health effects, with particular emphasis on evaluating the effects of perchlorate exposure 

on infants and young children. The Agency further announced that it planned to seek additional 

advice from the National Research Council ("NRC") on perchlorate before making a final 

determination. Since the time NRC last issued its January 2005 report on perchlorate,[FN1: National 

Research Council, Health Implications of Perchlorate Ingestion, National Academies Press, Board 

on Environmental Studies and Toxicology (January 2005). Subsequently in 2005, EPA adopted the 
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NRC recommended reference dose of 0.0007 mg/kg per day, which translates to a drinking water 

equivalent level of 24.5 ppb ("DWEL"). In January 2006 EPA's Superfund office issued guidance 

adopting the NRC reference dose and DWEL of 24.5 ppb as the recommended value to be 

considered as the preliminary remediation goal to guide perchlorate assessment and cleanup at 

Superfund sites. In January 2007, EPA reported that it had collected sufficient occurrence data, and 

that further monitoring was not needed for the Agency to make a regulatory determination. 72 Fed. 

Reg. 367 (January 4, 2007). In October of 2008, EPA announced a preliminary determination not to 

regulate perchlorate, noting that less than 1% of water systems have perchlorate levels above the 

health reference level. EPA concluded that perchlorate failed to meet two regulatory criteria (i.e., 

that a contaminant occur frequently at levels of health concern, and that establishing a national 

drinking water standard would provide a "meaningful opportunity for health risk reduction"). Then, 

in January 2009, EPA announced that it was replacing the perchlorate preliminary remediation goal 

of 24.5 ppb with an interim health advisory, establishing a nonenforceable concentration of 

contaminants in drinking water at which no adverse health effects are expected to occur, of 15 ppb. 

In the face of this uncertainty and regulatory history, debate over the science of perchlorate health 

risks has continued.] EPA has compiled and evaluated additional scientific studies relevant to 

perchlorate health effects and exposure that were not available to the NRC. However, in its August 

19, 2009 Notice, EPA announced that it would, in fact, not seek further review by the NRC because 

it believed such review would "unnecessarily delay" regulatory decision making for perchlorate. 

Concerns about protection of human health and the environment must always be in the fore front 

of our thinking, but to do so properly, sound science should not be sacrificed in the interest of mere 

expediency. The APA firmly believes that EPA should ask the NRC to review the new information 

to assist EPA with its determination. EPA has spent years assessing perchlorate's health effects and 

occurrence to determine whether a national standard is warranted.[FN2: Under the Safe Drinking 

Water Act ("SDWA"), [Sec] 1412, to regulate a contaminant in drinking water, EPA must determine 

that it meets three criteria: (1) The contaminant may have an adverse effect on human health, (2) the 

contaminant is known to occur or there is a substantial likelihood that the contaminant will occur in 

public water systems with a frequency and at levels of public health concern, and (3) regulation of 

such contaminant presents a meaningful opportunity for health risk reduction for persons served by 

public water systems. These legal criteria are premised on the use and application of sound science.] 

In the interest of obtaining the best available scientific information and advice, a comprehensive 

NRC review should be preferred.[FN3: The Notice specifically requested comment upon whether 

further review by the NRC is warranted, 74 Fed. Reg. 41884, and noted that if the Agency were to 

make a final decision to regulate perchlorate, it would seek review by the Science Advisory Board 

("SAB") prior to proposal of any maximum contaminant level goal and national primary drinking 

water rule. Id. However, the statutorily required review by the SAB under section 1412 of the 

SDWA to comment prior to setting the levels of a maximum contaminant level goal and national 

primary drinking water regulation, should not be a substitute for the timely scientific review of the 

NRC prior to the Agency's predicate decision making responsibility under the SDWA on whether 

regulation is warranted in the first place. Rigorous application of scientific review and sound science 

principles, especially by outside independent entities, should inform each statutorily- required 

regulatory step and decision, not only the final one. Indeed, it is the first step that has been the most 

controversial and it is that process of reevaluation in which the Agency is currently engaged.] 

EPA has, itself, recognized the significant scientific complexity involved here. "The public 

comments EPA received pursuant to the October 10, 2008, notice of preliminary regulatory 

determination and from the peer review of the supporting documents underscore the complexity of 
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the scientific issues regarding the regulatory determination for perchlorate in drinking water." 74 

Fed. Reg. 41884. Given that complexity, thorough review, analysis, and input from all available 

sources, including the NRC, should be sought to ensure full Agency consideration of the latest and 

best available science and thinking. 

EPA's website addressing "Using Sound Science" reiterates the importance of thorough scientific 

review: 

We depend upon sound science to do our work. Scientific information is especially important in the 

development of regulations. Whether we are developing a standard to protect the public from a 

newly recognized risk or defining monitoring requirements to gauge how well an environmental 

control is working, we incorporate the most current and credible scientific information into our 

regulation development process. . . . EPA relies, to the extent possible, on information that has 

undergone thorough peer review. During peer review, qualified, independent experts provide critical 

assessments to ensure that activities are technically supportable, competently performed, properly 

documented, and consistent with established quality criteria.... We also regularly solicit outside 

expertise from the National Research Council, other federal agencies with related responsibilities, 

and other scientific organizations.[FN4: Using Sound Science, available at: 

http://www.epa.gov/lawsregs/brochure/science.html] 

This Administration has reaffirmed the federal government's commitment to the principles of 

scientific integrity and the incorporation of full and open scientific review in all its policy-making 

functions. On March 9, 2009, the President issued his Memorandum on Scientific Integrity, directed 

to the heads of executive departments.[FN5: Available at: 

http://www.whitehouse.gov/the_press_office/Memorandum-for-the-Heads-of- ExecutiveDepartments-and-Agencies-3-9-09/), published at 74 Fed. Reg. 10671 (March 11, 2009).] The 

President stated: 

"science and the scientific process must inform and guide decisions of my Administration on a wide 

range of issues, including improvement of public health [and] protection of the environment." 

He charged the Director of the Office of Science and Technology Policy with "the responsibility for 

ensuring the highest level of integrity in all aspects of the executive branch's involvement with 

scientific and technological processes." As the President further emphasized: 

The public must be able to trust the science and scientific process informing public policy decisions. 

Political officials should not suppress or alter scientific or technological findings and conclusions. If 

scientific and technological information is developed and used by the Federal Government, it should 

ordinarily be made available to the public. To the extent permitted by law, there should be 

transparency in the preparation, identification, and use of scientific and technological information in 

policymaking. 

In response to the March 9 Presidential Memorandum on Scientific Integrity, we understand that 

EPA's Office the Science Advisor ("OSA") has been working with the White House Office of 

Science and Technology Policy ("OSTP") to develop recommendations for the President and with 

EPA's Science Policy Council to establish the EPA position on the topic. See 

http://www.epa.gov/osa/scientific_integrity.htm. As the OSA has explained: 
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The role and use of science at EPA are determined by the nature of scientific information and how 

it fits within the context of Agency decision-making. Scientific information--whether it comes from 

EPA, other agencies, academia, the regulated community, or other sources-- always includes some 

degree of uncertainty and is subject to varying interpretations. For example, assessments of risks to 

humans from exposure to chemicals are often based on tests in which laboratory animals are given 

high doses of a chemical. Effects seen in the animals may or may not appear in humans, who are 

typically exposed to much lower doses and whose bodies may metabolize the chemicals differently. 

In addition, there are often different scientifically justifiable ways to conduct risk assessments, and 

the method chosen by the assessor can significantly impact the risk estimate. 

Scientific knowledge is not only uncertain, but also dynamic. Through research that is designed to 

reduce uncertainties, our understanding increases and, as a result, we change our assumptions about 

the impacts of environmental problems and how they should be addressed.... 

Science does not drive EPA's policy and regulatory decisions, but rather, along with other relevant 

factors, informs and supports those decisions. Implementation costs and technological feasibility, 

local autonomy versus federal control, and justice and equity--all of which impact our quality of life 

and standard of living--are among the considerations that need to be factored into EPA's decisions 

without compromising scientific integrity, the Agency's mission, or statutory mandates. The impacts 

or limitations of these non-science factors, as well as the current state-of-the-science, will influence 

how scientific considerations are brought to bear on a particular environmental problem facing the 

Agency.[FN6: See http://www.epa.gov/osa/osa.htm.] 

Administrator Jackson recently testified in front of the U.S. Senate Committee on Environment and 

Public Works on "Scientific Integrity and Transparency Reforms at the Environmental Protection 

Agency" on June 9, 2009,[FN7: Available at: http://www.epa.gov/ocir/hearings/.] that "[t]he public 

health and environmental laws that Congress has enacted depend on rigorous adherence to the best 

available science... While the laws that EPA implements leave room for policy judgments, the 

scientific findings on which of these judgments are based should be arrived at independently using 

well-established scientific methods, including peer review, to assure rigor, accuracy, and impartiality." 

In her testimony, Administrator Jackson acknowledged that, "Environmental science is complex and 

multi-faceted, and able scientists may not always agree on what methodologies should be employed 

or how studies should be interpreted. I am committed to fostering a culture of robust scientific 

debate and discussion within the Agency, recognizing that in the end senior scientists must take 

responsibility for resolving differences of opinions using established science policies and their best 

professional judgment." 

APA respects and supports the Agency's paramount obligation to protect water quality and public 

health. We respectfully ask that the Agency take its own commitment to use sound science, as well 

as the directive of the White House to observe the highest principles of scientific-integrity, into 

account as it decides whether to ask the NRC or others to perform additional scientific review on 

the admittedly complex questions surrounding perchlorate. EPA has sought these additional 

comments from the public in "an effort to ensure consideration of all the potential options for 

evaluating whether there is a meaningful opportunity for human health risk reduction of perchlorate 

through a national primary drinking water rule." 74 Fed. Reg. 41883. No less so should EPA again 

seek the widely respected expertise, comments and advice of the NRC on this most difficult of 

public health issues, especially where that NRC review has proved so beneficial in the very recent 
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past to a full and robust consideration of the scientific data and uncertainties that must inform 

sound public health policy. 

Because the science and policy judgments underlying your decision-making for regulating 

perchlorate in drinking water are extraordinarily complex and will impact not only public health but 

also the environment and our businesses, full consideration of all available scientific information as 

well as all available peer review of that information, is clearly warranted. Please reconsider your 

decision not to seek further review by the NRC of all the critical studies, data, and risk analyses in 

this important process, so that EPA may have the benefit of the most rigorous and complete 

analysis of the available scientific data on which to deliberate and act. To ensure that this 

commitment to scientific integrity be met, while EPA could simply look at the same information 

again and ask the public if it has any new thoughts on how to interpret that information, we would 

respectfully suggest EPA request, as it originally intended to do,[FN8: See Congressional Research 

Service, CRS Report to Congress, Perchlorate Contamination of Drinking Water: Regulatory Issues 

and Legislative Actions, August t, 2009, p. 5.] that the NRC study and provide to EPA an evaluation 

of impacts to infants and young children from perchlorate and evaluate the more recent studies, 

EPA's use of models, and its derivation of the 15 ppb health reference level, as well. 

Thank you for your consideration of our comments and our request that the Agency take advantage 

of the full panoply of available means to incorporate rigorous scientific review into your process for 

reevaluating the risks, and the EPA's proposed additional approaches to analyzing the data, related 

to EPA's perchlorate determination. EPA should receive benefit of further NRC analysis of the 

latest data which will ensure that the Administration's commitment and mandate to use of sound 

science in policy- making is fulfilled. 

Respectfully submitted, Julie L. Heckman Executive Director cc: Administrator Lisa Jackson 

Assistant Administrator for Water 

Response: EPA is committed to the application of sound science and the principles of scientific 

integrity in its decision-making. The proposed path forward is designed to ensure adherence to both. 

See response to comment ID 28835 under comment code 2150. 

Commenter Name: Andria Ventura 

Commenter Organization: Clean Water Action et al. 

EPA Document ID: EPA-HQ-OW-2009-0297-0528 

EPA Comment ID: 28516 

EPA Comment Code: 2150 

Comment: Finally, we wish to discourage EPA from again referring the perchlorate assessment to 

the National Research Council (of the National Academies of Sciences) for further review. The last 

time (2005) the NRC reviewed perchlorate, it overstepped its charge and recommended a reference 

dose. This usurped EPA's authority and made it difficult for the public to comment at a key phase in 

the regulatory process. Furthermore, NRC committees meet a handful of times over many months. 

A referral would delay the process without a great deal of additional review. 

Response: See response to comment code 2150 and comment ID 28822 under comment code 

2150. 
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Commenter Name: Kathy Dolan 

Commenter Organization: Food and Water Watch (FWW) 

EPA Document ID: EPA-HQ-OW-2009-0297-0526 

EPA Comment ID: 28609 

EPA Comment Code: 2150 

Comment: Your decision to not request additional NRC review of issues relating to perchlorate is 

ill advised. Additional NRC research may better elucidate the health effect and exposure risk we 

presently face. Moreover, NRC research may provide better guidance in making a final regulatory 

determination, especially in determining the best health reference level (HRL). 

Response: See response to comment ID 28822 under comment code 2150. 

Commenter Name: Apparent Mass Mailing #11 - Food and Water Watch

EPA Document ID: EPA-HQ-OW-2009-0297-0526 

EPA Comment ID: 28615 

EPA Comment Code: 2150 

Comment: Your decision to not request additional NRC review of issues relating to perchlorate is 

ill advised. Additional NRC research may better elucidate the health effect and exposure risk we 

presently face. Moreover, NRC research may provide better guidance in making a final regulatory 

determination, especially in determining the best health reference level (HRL). 

Response: Please see the response to comment ID 28822 under comment code 2150. 

Commenter Name: Nsedu O. Witherspoon 

Commenter Organization: Children's Environmental Health Network 

EPA Document ID: EPA-HQ-OW-2009-0297-0674 

EPA Comment ID: 28741 

EPA Comment Code: 2150 

Comment: Finally, we wish to discourage EPA from again referring the perchlorate assessment to 

the National Research Council (of the National Academies of Sciences) for further review. A referral 

would delay the process without a great deal of additional benefit. 

Response: See response to comment code 2150 and comment ID 28822 under comment code 

2150. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28797 

EPA Comment Code: 2150 

Comment: HISTORY OF DELAY 

EPA had evidence in the 1980's that perchlorate was leaching from military dumpsites into 

groundwater, as documented in a 1985 interagency letter from EPA to the Centers for Disease 
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Control and Prevention (CDC) reporting on levels as high as 300-800 ppb "potentially affecting 

32,000 to 42,000 households."[FN24: As documented in: Sass J. U.S. Department of Defense and 

White House working together to avoid cleanup and liability for perchlorate pollution. Int J Occup 

Environ Health. 2004. Jul-Sep;10(3):330-4.] EPA set a provisional RfD of 0.0001 mg/kg/day in 

1992; this would have been equivalent to an MCL of 3.5 ppb in water, presuming an adult average 

body weight and daily water consumption, and presuming no other sources of perchlorate.[FN25: 

As documented in: Sass J. U.S. Department of Defense and White House working together to avoid 

cleanup and liability for perchlorate pollution. Int J Occup Environ Health. 2004. Jul- Sep;10(3):330-

4.] It has been 17 years since that provisional RfD, and in that time the science supporting that RfD 

has grown significantly stronger, along with public concern and Agency interest. Moreover, the RfD 

now finalized is 0.7 ug/kg/day, not dramatically different from the provisional RfD 17 years ago, 

given the extremely lengthy delay. 

EPA's progress on this assessment has been extensively and repeatedly reviewed by the interagency 

panel that was created in 1998 as a partnership between EPA, the U.S. Department of Defense , and 

other federal agencies to review perchlorate issues. 

In 2002, EPA issued an External Review Draft that recommended a limit of 1 ppb in drinking water. 

This was sent to the NRC for review in 2004, which resulted in the recommended oral RfD of 

0.0007 mg/kg/day, adopted by EPA in 2005. 

 REQUEST FOR COMMENT ON NRC REVIEW 

NRDC Response: Further Review by NRC Not Warranted 

After over 17 years of accumulated science (documented above), two EPA toxicological reviews 

(1998, 2002), and a lengthy NRC review (2004), it is past time for EPA to take effective regulatory 

action to protect people's health by preventing exposure to perchlorate. Therefore, NRDC supports 

the Agency's belief that further review by the NRC would create an unnecessary delay without 

adding anything to the scientific rigor of the Agency's determination. 

NRDC would likely support the Agency if it requested a review by its Scientific Advisory Board, 

since it would be more rapid and less costly than an NAS review, while providing scientific 

oversight. 

Response: See the response to comment ID 28822 under comment code 2150. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0227 

EPA Comment ID: 28822 

EPA Comment Code: 2150 

Comment: Given these significant concerns, EPA should also move forward with its alternative 

proposal to seek additional input from the National Research Council of the NAS, regarding the 

health impacts of (synthetic and natural) perchlorate, and should specifically request input regarding 

the issues presented in these comments, including the problems associated with the Greer NOEL 

and the RfD. 
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Response: The NRC previously studied perchlorate health implications from March, 2003 until 

they issued their report in January, 2005 (NRC, 2005). EPA has compiled and evaluated additional 

scientific studies relevant to perchlorate health effects and exposure available in the scientific 

literature since publication of the 2005 NRC report. EPA also has obtained peer review and public 

comment on the Agency’s analysis of a number of these studies. The Agency currently believes that 

further review by the NRC would unnecessarily delay regulatory decision making for perchlorate. 

EPA also notes in this August 19, 2009 Federal Register notice that if the Agency were to make a 

final determination to regulate perchlorate, the Agency, in accordance with the SDWA, would seek 

review by the Science Advisory Board prior to proposal of any maximum contaminant level goal and 

national primary drinking water rule. Therefore, EPA is not, at present, planning to request 

additional NRC review of issues related to perchlorate. 

National Research Council (NRC). 2005. Health Implications of Perchlorate Ingestion. National 

Academies Press, Board on Environmental Studies and Toxicology, January, 2005, Washington, 

D.C. 276pp. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28828 

EPA Comment Code: 2150 

Comment: Review By NAS. In the October 10, 2008 Federal Register notice (73 FR 60262) EPA 

stated that it would send its review of the science surrounding perchlorate again to the NAS. 

AMWA still believes the analysis should go to NAS for review although the association's reasons 

have shifted in light of the agency's new analysis of alternative HRLs. Specifically, AMWA believes a 

review by NAS of EPA's new analysis and methodology explained in this NODA for determining 

alternative HRLs is judicious because this analysis is the first time the agency has applied its 2005 

Guidance. It is also prudent as EPA is asking for comment on using the PBPK model for evaluating 

the relative sensitivity of the various life stages to perchlorate exposure in drinking water. 

AMWA recommends that EPA send both the revised PBPK model as well as the analysis used to 

derive alternative HRLs to NAS for review because the potential precedent that will be set if these 

analyses are used in rulemaking have significant ramifications for how policy is developed. 

Particularly where endocrine disrupting compounds are concerned, the impacts of particular 

chemicals on children's development must be properly characterized and modeled. Specifically, 

AMWA recommends that an NAS review panel be formed to address the questions posed in section 

A.4 of 74 FR 41886. In addition, NAS should be asked to determine the merits of the alternative 

approaches for calculating HRLs detailed in section B.3 (74 FR 41887-41889) and specifically with 

regard to EPA's request for comments in B.4 (74 FR 41889). 

AMWA has additional comments related to the NAS review later in this comment letter where 

EPA's specific requests for comment are identified. 

Response: See the response to comment ID 28822 under comment code 2150. 

Commenter Name: Diane VanDe Hei 
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Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28834 

EPA Comment Code: 2150 

Comment: Part II: Specific EPA requests for comment 

74 FR 41884: "EPA requests comment upon whether further review by [the National Research 

Council] NRC is warranted. EPA also notes that if the Agency were to make a final determination to 

regulate perchlorate the agency would seek review by the SAB prior to proposal of any MCLG or 

national primary drinking water rule." 

Response: In previous comments, AMWA suggested that EPA send its review of the perchlorate 

science to NAS for review by 2011 (or sooner if the agency so desires). As expressed earlier in this 

comment letter, AMWA still believes the analysis should go to NAS for review although the 

association's reasons have shifted in light of the agency's new analysis of alternative HRLs. 

AMWA disagrees with EPA that another review by NAS/NRC could slow the process. Previous 

NAS/NRC panels have finished their work in short time spans and EPA could convene a panel 

concurrent with the development of a perchlorate regulation, should the agency make a 

determination to regulate perchlorate. 

EPA states in the NODA that it will have the Science Advisory Board (SAB) review any regulatory 

determination made prior to proposal of the regulation. This is required in Section 1412 of the 

SDWA and AMWA agrees that this is a good and appropriate course of action. However, a SAB 

review would likely focus on the entire perchlorate regulatory proposal rather than specific 

components of the proposal. 

As a result, AMWA believes that a focused NAS/NRC review of the alternative HRL analysis that 

used EPA's 2005 Guidance as well as the 2008 Child-Specific Exposure Factors Handbook is 

necessary because of the broad potential policy implications for OGWDW and the analysis of future 

regulations. In addition, the mission of the NAS, in particular NRC, "is to improve government 

decision-making and public policy, increase public education and understanding, and promote the 

acquisition and dissemination of knowledge in matters involving science, engineering, technology, 

and health. The institution takes this charge seriously and works to inform policies and actions that 

have the power to improve the lives of people in the U.S. and around the world." 

(http://sites.nationalacademies.org/NRC/index.htm) 

A NAS/NRC panel should be selected with expertise in mind to address the questions put forward 

in the FR notice. The new analysis to determine HRLs, as well as the agency's additional 

consideration for using the PBPK model, should also be peer reviewed by experts who are well 

versed in modeling. 

Response: See the response to comment ID 28822 under comment code 2150. The SAB will 

consider all aspects of the NPDWR, including the scientific evaluations underlying it. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 
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EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28835 

EPA Comment Code: 2150 

Comment: Should EPA decide not to seek review by NAS, AMWA strongly recommends that 

EPA include in the charge to SAB the requests for comment surrounding the alternative HRLs 

analysis found in this NODA (Section A. 4 of 74 FR 41886). In addition, NAS should be asked to 

determine the merits of the alternative approaches for calculating HRLs detailed in section B. 3 (74 

FR 41887-41889) and specifically with regard to EPA's request for comments in B.4 (74 FR 41889). 

AMWA also strongly recommends that EPA provide at least six months for SAB to review the 

alternative HRL analysis and PBPK model as it relates to this analysis. EPA should also take care to 

ensure that there are sufficient reviewers with the proper expertise for the task. 

Response: See response to comment ID 28822 under comment code 2150. EPA will ensure that 

the charge to the SAB and the composition of the panel are appropriate for the review of the entire 

scientific underpinnings of the NPDWR. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection (MassDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0495 

EPA Comment ID: 28859 

EPA Comment Code: 2150 

Comment: Section II: Background 

MassDEP supports EPA's opinion that further review by the National Research Council (NRC) will 

delay regulatory decision-making and supports EPA's current plan to publish alternative approaches 

to interpreting the data on perchlorate and to consider public comments towards making a 

regulatory decision on perchlorate in drinking water. 

Response: EPA agrees with the commenter as discussed in the response to comment ID 28822 

under comment code 2150. Also, see response to comment code 2150. 
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EPA Comment Code: 2200 Use of NHANES biomonitoring data for health 

effects evaluation 

Response to Comment Code 2200: After a report prepared by the NRC (National Research 

Council) on “Health Implications of Perchlorate Ingestion” (NRC 2005) was released, several papers 

were published that investigated whether biomonitoring data associated with the National Health 

and Nutrition Examination Survey (NHANES) could be used to discern if there was a relationship 

between perchlorate levels in the body and thyroid function. Blount et al., (2007) published a study 

examining the relationship between urinary levels of perchlorate and blood serum levels of TSH and 

total T4 in 2,299 men and women (ages 12 years and older) who participated in CDC’s 2001–2002 

NHANES. Blount et al. (2007) evaluated perchlorate along with a number of covariates known or 

likely to be associated with T4 or TSH levels to assess the relationship between perchlorate and 

these hormones, and the influence of other factors on this relationship, including gender, age, 

race/ethnicity, body mass index, serum albumin, serum cotinine (a marker of nicotine exposure), 

estimated total caloric intake, pregnancy status, post-menopausal status, premenarche status, serum 

C-reactive protein, hours fasting before sample collection, urinary thiocyanate, urinary nitrate, and 

use of selected medications. The Blount et al. (2007) study found that perchlorate exposure was a 

statistically significant predictor of thyroid hormones (T4) in women with urinary iodine levels <100 

ug/l, but not in men. Blount et al. (2007) noted several limitations of their study and recommended 

that their findings be affirmed in at least one more large study focusing on women with low urine 

iodide levels. Since their study was cross-sectional in design, it also cannot be concluded whether or 

not the association between perchlorate and thyroid hormone levels is causal, or is mediated by 

some other correlate of both, although the relationship between urine perchlorate and total TSH 

and T4 levels persisted after statistical adjustments for some additional covariates known to predict 

thyroid hormone levels (e.g., total kilocalorie intake, estrogen use, and serum C-reactive protein 

levels). An additional paper by Blount et al., (2006), found that almost all participants in the 

NHANES survey, including the participants in this first group, had urinary levels of perchlorate 

corresponding to estimated dose levels that are below the RfD of 0.7 μg/kg/day. 

The Blount et al. (2006) study suggested that perchlorate could be a surrogate for another 

unrecognized determinant of thyroid function, since there are other chemicals, including nitrate and 

thiocyanate, which can affect thyroid function. Steinmaus et al., (2007) further analyzed the data 

from NHANES 2001–2002 to assess the impact of smoking, cotinine and thiocyanate on the 

relationship between urinary perchlorate and blood serum T4 and TSH. Thiocyanate affects the 

thyroid by the same mechanism as perchlorate (competitive inhibition of iodide uptake). Steinmaus 

et al. (2007) analyzed the NHANES data to determine whether smoking status (smoker or 

nonsmoker), serum thiocyanate, or serum cotinine were better predictors of T4 and TSH changes 

than perchlorate, or if the effects reflected the combined effects of perchlorate and thiocyanate. 

These authors found no association between either perchlorate or T4, and smoking, cotinine, or 

thiocyanate in men or in women with urinary iodine levels >100 μg/l. In addition, Steinmaus et al. 

(2007) found no association between cotinine and T4 or TSH in women with iodine levels <100 

μg/l. However, in women with urinary iodine levels <100 μg/l, they found that an association 

between urinary perchlorate and decreased serum T4 was stronger in smokers than in non-smokers, 

and stronger in those with high urinary thiocyanate levels than in those with low urinary thiocyanate 

levels. The authors concluded that for these low-iodine women, the results suggest that at 

commonly occurring perchlorate exposure levels, thiocyanate in tobacco smoke and perchlorate 
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interact in affecting thyroid function, and that agents other than tobacco smoke might cause similar 

interactions (Steimaus et al., 2007). 

Individual Comments 

Commenter Name: Carol Bigelow 

Commenter Organization: University of Massachusetts 

EPA Document ID: EPA-HQ-OW-2008-0692-1427 

EPA Comment ID: 20629 

EPA Comment Code: 2200 

Comment: The analyses that form the basis of docket ID No. EPA-HQ-OW-2008-0692, entitled 

"Drinking Water: Preliminary Regulatory Determination on Perchlorate" err significantly in the 

omission of critically relevant data sources. At a minimum, a critical evaluation of Blount et al 

(2006a) should be incorporated into the docket and the conclusions drawn therein should be revised 

accordingly. 

Another key data source that was omitted from consideration by the EPA is the relationship 

between perchlorate exposure and thyroid function identified by Blount et al. (Blount et al., 2006a). 

Blount et al., (2006a) results are consistent with a causal relationship between perchlorate exposure 

and thyroid function as follows: 

a. The strength of the relationship between urinary perchlorate and serum total T4 and serum TSH 

was greater in women with low urinary iodide (>100 ug/L). 

b. The strength of the relationship between urinary perchlorate and serum total T4 and serum TSH 

was greater in women who smoked (Steinmaus et al., 2007). 

c. Significant relationships with other ions known to affect iodide uptake were not observed. 

d. Given the known variability in urinary perchlorate levels (Blount et al., 2006b) and in T4 and TSH 

levels (Andersen et al., 2002; Andersen et al., 2003), a very large sample size would be required to 

identify these relationships. 

EPA cites the NAS report of 2005 (NRC, 2005) as indicating that epidemiological studies cannot 

identify a causal relationship between perchlorate exposure and thyroid function. However, the 

CDC study of 2006 represents a verification that known and predicted relationships between 

perchlorate exposure and thyroid function are occurring at environmental levels of perchlorate 

exposure in the human population. EPA must consider the statistical power of the CDC study to 

identify relationships of interest. These findings, furthermore, indicate that the high-dose, shortterm 

studies of Greer and others do not provide relevant information about the life-time low-dose 

exposure to perchlorate. Therefore, in the absence of a rational alternative to epidemiological studies 

to identify such relationships of interest in humans, EPA must employ the best available science - 

that of the Blount study. 

Response: 

See response to comment ID 29078 under comment code 2200. 
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Commenter Name: Rebecca Downey 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1888 

EPA Comment ID: 20772 

EPA Comment Code: 2200 

Comment: The EPA is choosing to ignore and dismiss several scientific studies, including thise 

from the CDC, that show that Perchlorate can cause serious thyroid disruption in women, children, 

developing fetuses and newborns. This is especially concerning in the unborn and newborn, as 

thyroid disruption effects brain development, that can lead to mental deficiences. 

Response: EPA has found that perchlorate may have an adverse effect on human health. EPA 

intends to develop a proposed NPDWR for perchlorate and will consider the best available, peer 

reviewed data as we develop the proposed NPDWR. 

Commenter Name: Lenny Siegel 

Commenter Organization: Center for Public Environmental Oversight 

EPA Document ID: EPA-HQ-OW-2008-0692-2019 

EPA Comment ID: 20854 

EPA Comment Code: 2200 

Comment: More important, though it draws upon the work of the Centers for Disease Control to 

profile perchlorate exposures in the population, it dismisses one of its key findings: In 2006 Blount 

et al found that women with low iodide levels (over a third of the female population) experience 

decreased thyroid functions at low perchlorate exposures characteristic of much of the U.S. 

population. That effect could seriously impair the development of fetuses carried by such women. 

But EPA states that Blount did not establish a causal relationship. That is, other factors-such as 

exposure to nitrates or thiocyanate, might be influencing thyroid function. It wrote, "It is also not 

known whether the association between perchlorate and thyroid hormone levels is causal or 

mediated by some other correlate of both." 

That is, EPA recognizes that there is a major threat to public health, but it refuses to take action 

because there is a chance that the association between perchlorate and decreased thyroid function 

might be caused by another. unknown chemical compound. Yet EPA promises no action to track 

down and investigate that mysterious cause. This is unconscionable! 

Response: See response to comment ID 29078 under comment code 2200 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20901 

EPA Comment Code: 2200 
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Comment: Even with the errors and bias that the use of the CIIT computer model injects into 

EPA’s assessment, EPA still concludes that up to 2 million people may be consuming drinking water 

that exceeds the HRL, including tens of thousands of infants and young children. The agency then 

dismisses these impacts as not significant enough to justify setting a drinking water standard for 

perchlorate. If EPA had used CDC’s real world data in it’s assessment instead of the flawed 

computer model, a much higher number of infants, children, and women of childbearing age would 

be found to be at risk. 

Response: See response to comment ID 28608 under comment code 2200. Also, see response to 

comment ID 20903 in comment code 2200 and response to comment code 5220. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20903 

EPA Comment Code: 2200 

Comment: Introduction: 

In this assessment, EPA relies primarily on a physiologically-based pharmacokinetic (PBPK) model 

to estimate risks to different populations from perchlorate contamination of drinking water. This 

approach is somewhat suspect to begin with because it is based on a computer model, rather than 

on the wealth of data from human studies on perchlorate. Recent large, well-conducted human 

studies on perchlorate have revealed that exposure to this thyroid toxin is widespread among the 

U.S. population and that women with lower iodine levels are a particularly vulnerable group, in 

addition to breast-fed infants and young children. 

Response: Several commenters supported the use of the PBPK model to inform the regulatory 

determination only if the significant limitations of the current model are addressed. For example, the 

inability of the model to reflect iodide nutritional status was cited by commenters and three of four 

peer reviewers as an important limitation (USEPA, 2008d). Also, several commenters stated that the 

risks to breast-fed infants and young children are not adequately addressed by the model. They 

challenged that the modeling analysis is based on average weight infants and healthy adults, while the 

sensitive life stages for perchlorate include premature infants and hypothyroid women. 

After further consideration of the peer review and public comments, EPA concludes that the PBPK 

modeling analysis, in the context of the perchlorate regulatory determination, is useful in examining 

which life stages are most susceptible to the effects of perchlorate. For example, the model indicates 

that a fetus may be seven times more sensitive to the effects of perchlorate than a pregnant woman. 

The model also allows for the estimation of the concentration of perchlorate in breast milk (thus 

breast-fed infant exposure) at various maternal perchlorate exposure levels. However, because of the 

stated limitations, EPA has decided the model does not directly bear on the current decision 

regarding the need for a NPDWR for perchlorate. EPA is continuing to evaluate whether the model 

could be used in setting a NPDWR for perchlorate. 
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Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20909 

EPA Comment Code: 2200 

Comment: Background 

Recent research from the CDC and the Food and Drug Administration (FDA) provide strong 

evidence that perchlorate exposure among the U.S. population presents potential health threats that 

justify strong protective measures by public health agencies. The most compelling findings from 

recent research from government agencies and academic scientists are summarized below: 

* CDC tested 2,820 U.S. residents (ages 6 an older) in a nationally representative sample and found 

detectable levels of perchlorate in the urine of every person tested (Blount et al. 2006a); 

* Urinary perchlorate levels in children ages 6 to 11 were 1.6 times higher than levels in adults 

(Blount et al. 2006a); 

* CDC scientists analyzed both perchlorate and thyroid hormone levels in more that 1,000 U.S. 

women and found that in the one third of women with lower iodine levels, perchlorate exposure far 

below EPA RfD of 0.7 ug/kg/day was associated with significant changes in thyroid hormone levels 

(Blount et al. 2006b); 

* Using CDC data, an EWG analysis found that 2 million women of childbearing age may be at risk 

for abnormal thyroid hormone levels during pregnancy (EWG 2006); 

* CDC and academic scientists have tested a combined 118 samples of U.S. breast milk in 4 

different studies and have found perchlorate in every sample tested (Dasgupta et al. 2008, Kirk et al. 

2005, Kirk et al. 2007, Pearce et al. 2007); 

* Breast milk studies suggest that a significant number of breast fed infants may be exposed to 

perchlorate at levels that exceed the EPA RfD of 0.7 ug/kg/day (Dasgupta et al. 2008, Kirk et al. 

2005, Kirk et al. 2007, Pearce et al. 2007); 

* FDA scientists found perchlorate in three quarters of nearly 300 commonly consumed foods and 

beverages; young children are exposed to perchlorate doses that fall between 50 to 56% of EPA’s 

RfD from food alone and could easily exceed EPA’s RfD with additional drinking water exposures 

(Murray et al. 2008); 

* A recent study from scientists at the University of Texas found that breast tissue concentrates 

perchlorate at 3 times the rate of iodine (Dasgupta et al. 2008). 

This body of data from a number of respected sources including CDC, FDA, and academic 

scientists provides compelling evidence that establishes widespread exposure to perchlorate among 

the U.S. population and toxicity in a vulnerable population (women with lower iodine levels). The 

findings of widespread food contamination are especially concerning for young children, who eat 

more food and drink more water per unit of body weight when compared to adults. 
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EPA’s decision not to regulate perchlorate in drinking water in the face of such compelling facts is 

irresponsible and indefensible given the strength of the evidence for stringent regulation. In fact, 

EPA reached its decision by using flawed models and methodology; following are some of the most 

glaring reasons that this assessment is inadequate. 

Response: EPA agrees that perchlorate occurs at a frequency and at levels of public concern in 

public water systems and intends to develop an NPDWR for perchlorate. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20912 

EPA Comment Code: 2200 

Comment: EPA relies on flawed computer model while downplaying significance of human data: 

As noted above, EPA relies heavily on a deeply flawed computer model that predicts RAIU 

inhibition at various levels of perchlorate contamination of drinking water. The dependence on such 

a computer model would be more understandable were there not comprehensive human data on 

perchlorate exposure and toxicity. However, in the last two years, government agencies like CDC 

and FDA, as well as prominent academic scientists, have published studies establishing widespread 

perchlorate exposure among the U.S. population, with especially high exposures among breast-fed 

infants and young children, and evidence of toxicity among women with lower iodine levels. 

CDC published a ground breaking study in 2006 showing that current perchlorate exposures are 

associated with significant effects on thyroid hormone levels in women with low urinary iodine 

levels. EPA deliberately downplays the significance of these findings, noting that CDC findings are 

contradicted by another study: "Results from studies of the effects of perchlorate exposure on 

hormone levels have been mixed. One recent study did not identify any effects of perchlorate on 

blood serum hormones (Amitai et al. 2007), while another study (Blount et al. 2006b) did identify 

such effects" (EPA 2008). 

However, when the Amitai et al. study is reviewed, it is clear that the results of this study do not 

contradict the results from Blount et al.; in fact, the study authors themselves note, "Based on 

differences in iodine intake and life stages for the two studies, our findings do not contradict those 

of Blount et al." (Amitai et al. 2007). Yet, EPA maintains that the results from Amitai et al. provide 

evidence to doubt CDC results although the two studies are completely different and the CDC study 

is the only one to have established unique vulnerability to perchlorate among women with lower 

urinary iodine levels. By raising doubts about the validity of CDC findings, despite no scientific 

justification, EPA is able to downplay the significance of these findings to justify excluding them in 

their assessment. 

Response: See response to comment ID 20909 under comment code 2200. Also see responses to 

comment IDs 29078 regarding the Blount et al. study and 20903 regarding PBPK modeling under 

comment code 2200. 
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Commenter Name: Caroline Baier-Anderson, PhD 

Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20946 

EPA Comment Code: 2200 

Comment: CDC Studies Reveal Relationships between Perchlorate Exposure and Thyroid 

Hormones that Make Biological Sense 

CDC researchers evaluated the relationship between urinary levels of perchlorate (which was found 

in every individual tested and at significantly higher levels in children, and serum levels of TSH and 

total T4 in 2,299 men and women, >=12 years of age, participating in the CDC-sponsored National 

Health and Nutrition Examination Survey (NHANES) during 2001-2002 (Blount et al. 2006, 2007). 

This study found that: 

* All individuals tested were exposed to perchlorate. * Children had significantly higher levels of 

perchlorate exposure, * For all women >=12 years of age, multiple regression analysis found urinary 

perchlorate to be a significant predictor of serum TSH and a significant predictor of serum T4. * For 

women with urinary iodine < 100 ug/L, multiple regression analysis found perchlorate to be a 

significant predictor (p < 0.0001) of T4 with a coefficient for log perchlorate of -0.8917. * 

Perchlorate was also a significant predictor (p = 0.0010) of log TSH with a coefficient of 0.1230. 

Hence, the results of the Blount study more closely reflect our understanding of the biological and 

toxicological processes pertaining to thyroid homeostasis, both in terms of thyroid hormone 

variability and the role of iodine. The researchers conclude that "[i]ncreased urinary perchlorate was 

associated with increased TSH and decreased T4 for women with urinary iodine levels < 100 ug/L, 

a group possibly more susceptible to competitive inhibition of thyroid iodine uptake by perchlorate. 

The statistically significant associations of urinary perchlorate with decreased serum T4 and 

increased serum TSH were consistent with competitive inhibition of iodide uptake." 

The Blount study also validates findings of previous CDC study that 36 % of women in the National 

Health and Nutrition Examination Survey (NHANES), 2001-2002, had low iodine intake (< 100 

ug/L urinary iodine) (Caldwell et al. 2005) , which translates to approximately 43 million US women 

(Pirkle 2007). 

Response: See response to comment ID 29078 under comment code 2200. 

Commenter Name: Caroline Baier-Anderson, PhD 

Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20948 

EPA Comment Code: 2200 

Comment: EPA Fails to Recognize the Importance of Iodine and Individual Variability 

On page 60268 of the Federal Register Notice, EPA suggests that a study by Amitai et al. (2007) 

provides information that contradicts the findings of the Blount study, stating that measured T4 
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values were not associated with perchlorate levels, despite the fact that the perchlorate levels were 

much higher than in the CDC study. Amitai et al. directly address this comparison, asserting that 

because of differences in the study population between the Amitai and Blount studies, the studies 

are not contradictory: 

"A previous study of pregnant women in the coastal areas of Israel indicates iodine sufficiency 

(urinary iodine median=143 ug=L, mean=130 ug=L) based on World Health Organization (WHO) 

criteria. Another important difference between the current work and the Blount et al.'s study is the 

study population: we examined thyroid function in neonates, while Blount et al. studied adults and 

adolescents. Based on differences in iodine intake and life stage for the two studies, our findings do 

not contradict those of Blount et al." (emphasis added) (Amitai et al. page 848). 

Another earlier study evaluating high levels of exposure to perchlorate (the Chilean study) also 

involved a population that was iodine sufficient (Tellez et al. 2005). Taken together these studies 

indicate they iodine sufficiency is a critical component of resistance to perchlorate effects. With over 

1/3 of US women demonstrating insufficient iodine intake, iodine status must be considered as an 

important characteristic of the exposed population. 

EPA's failure to appropriately account for both individual variability and iodine status ignores 

important biological and toxicological considerations and has contributed to the selection of a 

reference dose that is not adequately protective of sensitive subpopulations. 

We strongly recommend that the CDC data analyzed in the study by Blount et al. 2006 and Blount 

et al. 2007 be used as the basis for the derivation of a new reference dose. One option would be to 

estimate perchlorate dose from urinary perchlorate using an equation developed by Mage et al 2004 

and applied by Blount et al. 2007. EPA could then estimate benchmark doses of perchlorate 

associated with benchmark responses for abnormally low T4 serum concentrations and abnormally 

high serum TSH concentrations in women with low urinary iodine excretion. EPA could use the 

BMD low (representing the lower limit of a one- sided 95% confidence interval), which more 

accurately reflects the statistical power inherent in the study design than the NOAEL (or NOEL, or 

LOEL for that matter), and more efficiently utilizes the dose-response data while being less sensitive 

to the spacing of doses. An uncertainty factor may be necessary to ensure the protection of the fetus 

and neonate. There are likely to be other approaches to data analysis that accounts for sensitive 

subpopulations, including individual variability, iodine status and windows of vulnerability and we 

encourage EPA to re-evaluate these options. 

Response: See response to comment ID 29078 under comment code 2200. EPA accounts for 

individual variability by incorporation of an intraspecies uncertainty factor in the derivation of the 

RfD. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20970 

EPA Comment Code: 2200 

Comment: This value could be further checked against the NHANES data: 
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The effective perchlorate equivalent NOEL (NOEL3) as explained before is 7.04 + 5.8 = 12.8 

ug/kg-day. This, as explained before, leads to a new RfD of 1.28 ug/kg-day applying the same UF of 

10. 

The background of the other 2 goitrogens represents 40% of NOEL3 (5.8/12.8= 0.4) (and the 

perchlorate background 0.3%). 

Therefore the RfD for perchlorate alone for the general population would be 1.28x 0.6 = 0.77 

ug/kg-day and the HRL would be 27 ppb. 

This is very close to the 26.7 ppb assigned above as HRL for perchlorate alone in the perchloratenitrate cup if the nitrate HRL would also be subject to an UF of 10 and it is also close to the current 

EPA DWEL of 24.5 ppb. 

In any case it would not have much sense as a public health policy and in particular in terms of 

thyroid protection to try to arrive at the most accurate DW HRL for perchlorate and leave the 

nitrate MCL at such levels that this effort would be completely nullified. 

Therefore it should be recommended to set a joint HRL of 45 ppb perchlorate equivalent for nitrate 

and perchlorate combined. 

Response: See response to comment ID 29078 under comment code 2200. EPA cannot comment 

on a value for combined nitrate and perchlorate because that has not been peer reviewed. 

Commenter Name: 

Commenter Organization: Ag Council et al 

EPA Document ID: EPA-HQ-OW-2008-0692-1987 

EPA Comment ID: 20978 

EPA Comment Code: 2200 

Comment: The Blount (2006) Analysis of Perchlorate Data has Several Limitations and EPA 

Should not Rely on its Conclusions to Make Regulatory Decisions. 

The argument has been made that the Blount (2006b) results, which show a slight correlation 

between perchlorate in urine and changes in thyroid hormone levels in women with sub-optimal 

iodine levels, should be given considerable weight by EPA in making its regulatory determination for 

perchlorate. This work has several limitations which necessarily impede its use in drawing 

conclusions regarding the health effects of perchlorate, particularly for purposes of regulatory 

decision making. Chief among these is the fact that Blount (2006b) does not establish direct 

causation, only an association between two independent data sets. A number of intervening factors 

could cause or contribute to the reported decrease in thyroid hormone levels. Moreover, the Blount 

(2006b) results conflict with the overwhelming body of scientific evidence showing no effect on the 

thyroid at environmentally relevant levels. Dr. Blount himself has acknowledged the limitations of 

his results. Similar concerns have been raised by independent organizations such as the American 

Thyroid Association. 
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The California agricultural industry appreciates US EPA's consideration of our comments on its 

preliminary regulatory determination for perchlorate. We remain committed to working with US 

EPA, FDA and individual states to preserve the safety of our products and their contribution to 

balanced, heallthy diets. 

Sincerely, 

Ag Council California Citrus Mutual California Cotton Ginners and Growers Association California 

Farm Bureau Federation California Grain and Feed Association California Grape and Tree Fruit 

League Grower-Shipper Association of Central California Grower-Shipper Association of Santa 

Barbara and San Luis Obispo Counties Imperial Valley Vegetable Grower Association Ventura 

County Agricultural Association Western Growers Western Plant Health Association Western 

United Dairymen 

Cc: Benjamin Grumbles, Assistant Administrator, U.S. EPA Office of Water Nega Beru, Director, 

U.S. FDA Office of Plant Dairy Foods and Beverages Charles F. Conner, Deputy Secretary, U.S. 

Department of Agriculture 

Response: See response to comment ID 29078 under comment code 2200. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-2082 

EPA Comment ID: 21024 

EPA Comment Code: 2200 

Comment: 7. Next, your letter raises the issue of the NHANES 2001-2002 survey results and the 

Blount et al. 2006b study. 

It is important to note that the results of the NHANES survey reveal that the US population is not 

exposed to levels of perchlorate that could cause an adverse effect, even when all exposure sources - 

in food and water - are considered. There has been considerable discussion over the role of the 

Blount study in the regulatory decision-making process. Those who support its use point to the 

specific finding that perchlorate levels were a negative predictor of total T4 and a positive predictor 

of TSH in women with urinary iodide less than 100 μg/L. While the findings of the study are 

interesting, the specific finding at issue is not able to determine causation and is simply based upon 

an association between two variables. The study directly conflicts with the large number of studies 

that have shown no effect at environmental levels. Government agencies and private organizations, 

including the Agency for Toxic Substances and Disease Registry, the American Thyroid Association 

and the Toxicology Excellence for Risk Assessment (TERA), have identified several limitations 

concerns with the Blount study. As a result they recommend that based on its status as solely an 

associational study and as well as the numerous limitations, it should not be used in regulatory 

decision-making. 

ATSDR (2008) reviewed the Blount et al. (2006b) study in their assessment. ATSDR did not believe 

that it merited any special consideration over other studies in the well developed perchlorate 

literature database. They stated that their decision "...was made after a careful evaluation of the NRC 
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report and of studies that have been published after the NRC (2005) report. The results from newer 

studies do not change the bottom-line recommendation" (ATSDR, 2008). 

The lead author, Dr. Benjamin Blount, has acknowledged several limitations with the study and that 

its results require validation. At an NAS workshop on risk assessment considerations for thyroid 

active compounds [FN5: National Research Council Fifth Workshop of the Standing Committee on 

Risk Analysis Issues and Reviews, Risk Assessment Considerations for Interpretation of Bioassay 

Data and Human Biomonitoring Data for Thyroid-Active Compounds: Issues of Variability, Critical 

Reproductive-Developmental Periods, and Cross-Species Comparisons, May 15-16, 2008.], Dr. 

Blount reviewed the results of this study and identified several limitations with the study: 

* due to other missing data, perchlorate could be a surrogate for an unknown variable; 

* the study is only a cross-sectional association, recognizing that it does not establish a direct 

causation between perchlorate levels and thyroid hormone levels; 

* although this study looked at total T4, free T4 is a better measure, and 

* the study was based upon a weak iodine assessment. [FN6: Ben Blount, Biomonitoring Data on 

Thyroid-Active Compounds: Database and Issues Regarding Variability and Interpretation, 

presented at NAS workshop in note 1 above, May 15, 2008.] 

8. Please see the attached copy of our comments recently submitted to the EPA docket for a more 

extensive discussion regarding concerns and limitations of the Blount study and its inappropriate use 

for regulatory decision-making. 

Response: See response to comment ID 29078 under comment code 2200. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21038 

EPA Comment Code: 2200 

Comment: RE: Docket ID No. EPAHQ- OW-2008-0068 Comments on the US Environmental 

Protection Agency’s Preliminary Regulatory Determination on Perchlorate November 28, 2008 

I am submitting these comments unanimously since I am employed in an organisation that may not 

consider these comments acceptable. 

Thank you for the opportunity to comment on the USEPA Office of Water’s Preliminary 

Regulatory Determination on Perchlorate. 

Comment subject 

EPA refers to the Blount et al., (2006b) study and EPA mentions that in that study other covariates 

were evaluated besides perchlorate. 
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Of those covariates only 2 were substances that, just as perchlorate, have a potential effect on TSH 

and T4 levels i.e. nitrate and thiocyanate. 

EPA also mentioned that "The researchers state that perchlorate could be a surrogate for another 

unrecognized determinant of thyroid function". 

We would like to comment on the fact that a multitude of other substances exist in the environment 

that can affect the level of those thyroid hormones and that most probably perchlorate is the 

surrogate, the marker for this pool of substances and nothing else. 

Summary 

More than 2 years after the publication of the Blount et al., (2006b) study there exist still doubts and 

EPA seems to confirm this, that the very low levels of perchlorate, in contrast to the body of 

literature, would be the cause of the observed thyroid hormone level change. 

The following reasoning should eliminate this doubt. 

1. Circumstantial evidence 

1.1. The effect level found in the Blount study at 10,000 times or 4 orders of magnitude lower than 

consistently found hitherto in the body of literature is unlikely. 

1.2. If it still would be seen as likely, then consequently the current EPA HRL should be divided by 

10,000 from 24.5 ppb to 0.002 ppb and even to 0.0002 ppb if an additional UF (uncertainty factor) 

on top of the NRC UF of 10 would be applied (as has been suggested by some, justified or not ). 

1.3. Iodine uptake inhibition precedes any adverse health effect of perchlorate exposure including 

TH (thyroid hormone; here T4 and/or TSH) level change so perchlorate cannot have an effect on 

TH when there is no iodine uptake inhibition in the first place. Evidence from the NHANES data 

on which the Blount study was based shows that overall, most probably iodine inhibition did not 

exist. 

1.4. The relationship of 2 other well known iodine uptake inhibitors with TH. 

1.4.1. Their "unexpected" relationships Thiocyanate and nitrate show relationships with TH and 

iodine in an "unexpected" direction and contrary to the perchlorate relationship with TH and iodine 

which was in the "expected" direction (and then only for iodine insufficient women; the direction 

was "unexpected" as well for iodine sufficient women). 

If those would be assumed to be causal as well - and they should be if the relationship with 

perchlorate is assumed as such- then the competitive uptake inhibition mechanism as we know it 

should be discarded and dietary increase of iodine should always be discouraged. The same should 

be said also regarding the relationship of perchlorate with TH for iodine sufficient women. We have 

not heard those proposals. 
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1.4.2. Their strength level The other 2 goitrogens, thiocyanate and nitrate, with the same mode of 

action as perchlorate do not show this "expected" relationship even though their equivalent levels 

are 28 and 56 times higher respectively. 

Conclusion of 1.4.: If all other relationships found are considered highly implausible(in the opposite 

direction of what should be "expected") to be causal, what can be the justification to single out one 

as causal because it seems to fit the "expectations" and explain away all the other relationships as 

"unclear" since they do not fit those expectations? 

2. The number and probability of possible alternative causes 

2.1. Why should those possible alternative causes have been considered with priority? Since it was 

shown that iodine levels overall were probably not relevant we should not look for something that 

affects NIS (and therefore potentially but only indirectly TH levels) but something that affects TH 

levels directly. 

It is surprising that EPA does not raise this issue but limits itself to mentioning nitrate and 

thiocyanate. If the Blount et al. study were about iodine uptake inhibition effect then this would 

have been justified. But it was not. 

It was about the downstream effect, the effect on TH. 

2.2. Covariates that have not been taken into consideration in the study and should have been so 

with priority. 

There are many widespread contaminants that are goitrogenic with effects on TH levels via 

mechanisms unrelated to iodine uptake such as organohalogens and other dioxin-like compounds 

which are ubiquitous and include many pesticides as well. 

They act thru different mechanisms. 

Only PCBs already include 209 congeners that vary based on the number and positions of chlorine 

atoms. 

Other substances such as Bisphenol-A , methylmercury are believed to be goitrogenic, even 

halogens like bromide or fluorine added in drinking water (besides chlorine) or their reaction 

products. Added to these should be natural goitrogenic substances such as isoflavones, genistein, 

resveratrol, silymarin and linuron. 

Data on some were available in the same 2001-2002 NHANES database from which perchlorate, 

iodine and the other 2 NIS goitrogens were extracted. 

Many studies including several EPA sponsored studies deal with those other goitrogens; some even 

include perchlorate in parallel. 

The question should then be asked: why were those goitrogens not controlled for or at least referred 

to as possible causes? 
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2.3. The level found compared with the effect level 

The known threshold effect level on THs of organo halogens such as PCBs and other dioxin-like 

substances and their levels in the NHANES 2001-2002 database have been found to be in the same 

range and some showed a relationship with THs as well. 

This is in stark contrast with the 4 orders of magnitude difference for the corresponding levels of 

perchlorate in the Blount study. 

3. What then could be the link between perchlorate and those known endocrine disruptors? 

The most obvious and most widely spread common link is chlorine. 

On one hand it has been shown that chlorine based disinfectants such as those found in drinking 

water (DW) oxidize to perchlorate as a disinfection by-product (DBP). 

This is for example the reason why Massachusetts doubled its MCL from 1 to 2 ppb. 

This oxidation is significant as it corresponds to about 1/3 of the average daily intake of perchlorate 

according to the Blount study (from the NHANES data). 

Bleach is used ubiquitously as for example in water purification stations, paper mills, drinking water 

and for many other applications. 

Other potential sources of perchlorate as a DBP are other chlorine derivates such as chlorine gas 

and chloramine. 

On the other hand other DBPs originate from the reaction of chlorine based disinfectants with 

organic matter (waste) to form organochlorides. 

There are 2 DBP pathways that link perchlorate and those other goitrogenic substances with 

chlorine: 

DBP road 1: Bleach/Cl2/Cl-/chloramine ->ClO-3 ->ClO-4 

DBP road 2: (in presence of organic (C) material): 

Bleach/ Cl2/Cl-/ chloramine ->phenols ->organochlorides/dioxins 

So chlorine is one example of the link between very low levels of perchlorate and TH affecting 

substances. 

Since organo-chlorinated compounds are ubiquitous and since we find around 1/3 of the total 

dietary perchlorate where we find organo-chlorinated compounds and since many of those have 

been shown to affect TH levels it is to be expected that low levels of perchlorate are associated with 

TH levels as found in the Blount study. 
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Yet assigning cause to this association would be against all common sense as overwhelming 

circumstantial evidence points in another direction. 

Perchlorate seems to be rather a marker, a witness, a messenger of the presence of ubiquitous 

goitrogenic contamination caused by the net effect of hundreds of substances (see also next section). 

4. Would this be the final answer: organochlorides are the sole cause of the (slight) TH changes? 

Probably not. 

There seems to be a ubiquitous contaminant pool in which there are all kinds of goitrogenic 

substances acting thru all kind of mechanisms that influence TH levels and thyroid function. 

Somehow they could be all linked together. 

So it seems plausible that perchlorate is a marker of this ubiquitous pool of thyroid function 

affecting contaminants which means that the more perchlorate is found (outside from the point 

source contaminations of course) the more goitrogenic the pool will be via the chlorine and halogen 

link and therefore the more goitrogenic effect on THs will be seen. 

5. Conclusion 

The answer to the question of what caused the Thyroid hormone changes in the Blount study is: all 

of the above except perchlorate as seen at those very low levels. 

It may be felt as politically rewarding to look for a simple explanation but, from what precedes such 

a simplistic and irrational interpretation would certainly not lead to effective health protective 

measures. On the contrary it would lead to a feel good situation with only illusory effects. 

A careful analysis should precede any sweeping statements like those we are seeing in some media. 

We hear a lot about holistic approaches in health risk assessment but not many practical 

applications. This may be one of them. 

Response: See response to comment ID 29078 under comment code 2200. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21039 

EPA Comment Code: 2200 

Comment: In trying to establish a HRL (Health Reference Level) for drinking water, EPA seems to 

be torn between the 2005 NRC RfD (reference dose) [see reference 1], referred to as "NRC RfD " 

hereafter, and a subsequent study [see reference 2], referred to as "Blount" hereafter, that, on first 

sight, appears to undermine this very RfD. 

This study showed a relationship between extremely low levels of perchlorate and TH (thyroid 

hormone; here T4 and/or TSH) levels. 
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As a result this relationship has been considered by many as a cause effect relationship suggesting 

(adverse) effects at a level of perchlorate much lower than that of the NRC RfD, which itself is 

based on the body of literature. 

All kind of erudite and highly complex reviews came out during the following 2 years either 

supporting or weakening the perceived consequences of this new finding. 

Did all this bring us today one step closer to an explanation of this significant contradiction? No, it 

did not. 

Yet it is abundantly clear that there is an evident overall fallacy that has not been exposed. EPA 

rightly points out, as many have done before, that a cross- sectional study, such as the Blount study 

can show associations but cannot decide causes. 

The main reason is that it does not allow control for non quantified (measured) covariates or for 

quantified covariates that were not considered relevant but that should have been. 

In order to evaluate the likelihood of this hypothetical cause-effect relationship the following 3 

aspects should be appraised: 

1. The presence of circumstantial evidence i.e. a collection of facts that, when considered together 

would conclude in favour or against the hypothesis. 

2. The number and probability of possible alternative causes. 

3. The link of these alternative causes with the hypothetical cause. 

Let’s see how those 3 obvious criteria work out. 

Response: See response to comment ID 29078 under comment code 2200. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21040 

EPA Comment Code: 2200 

Comment: 1. Circumstantial evidence 

1.1. The 4 orders of magnitude difference in levels From Blount ( NHANES 2001-2002) data and 

regression curves, the average urinary level of 2.84 u, which is found to be related to thyroid 

hormone (TH) change, is equivalent to an oral perchlorate dose of approximately 0.00004mg/kgday. 

This is 100 times lower than the dose of 0.004 mg/kg-day that was found to be without effect not 

even on iodide uptake [see reference 1] and which led to the NRC RfD. 
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Further this dose of 0.004 mg/kg-day on itself is about 100 times smaller than 0.5mg/kg-day, the 

dose found to have no effect on TH [see reference 1]. 

So, in stark contradiction to what was found in the body of the literature, the Blount study would 

suggest, if the relationship perchlorate /TH would be seen as causal, that perchlorate is 10,000 more 

potent than formerly found. 

[see figure in PDF docket ID EPA-HQ-OW-2008-0692-1990] 

The following illustrates the effect of 4 orders of magnitude: A dose of perchlorate used to treat 

Graves disease (excess thyroid function) and which was known since decennia to be effective at 

about 700 mg/day or 10 mg/kg-day would all of a sudden be effective at 0.001mg/kg-day, a dose 

that is not only 10,000 times lower than prescribed but also 500 times lower than the dose that only 

may start to have the intended effect but on euthyroid people instead (0.5 mg/kg- day). At that time 

would it have been likely that a 10,000 times overdose would have been recommended during 

several decades knowing that the side effects finally caused this remedy to be pulled from the 

market? This is highly improbable to say the least. 

Another image for the most tenacious readers: To make it more visually comprehensible for their 

readers, the NRC RfD of 0.0007 mg/l has often been expressed in the media as "a couple of drops 

in an Olympic seized swimming pool". 

The 10,000 times lower dose would then mean that about 9900 swimming pools of that size should 

be first build in the U.S. before it would be possible to further dilute those same couple of drops to 

this level since there are only about 100 of those pools existing.. 

In any case if this first massive conflict would still not be considered relevant or convincing (for 

reasons that then should be explained however) and the extremely low level causal effect would still 

be seen as probable then at least the consequences should be consistent which leads us to the 

second circumstantial evidence: 

Response: EPA cannot comment on the calculations by the commenter that have not been peer 

reviewed. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21041 

EPA Comment Code: 2200 

Comment: 1.2. The new MCL that should be recommended accordingly 

This means the RfD and the corresponding MCL (or HRL) should be lowered accordingly and not 

from 24.5 ppb to, say, 1 ppb (half the Massachusetts MCL, the lowest state MCL) but to 0.24 or 

0.024 ppt (if applying an UF of 10 or 100 respectively) or 0.0002 / 0.00002 ppb. 

We have not heard this claim. If this causal relationship would nevertheless exist then this 

corresponding low level should be suggested as an MCL or HRL. Yet the lowest MCL we have seen 
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proposed in relation to this "new finding" was only about 10-50 times lower than the NRC RfD. 

This shows that even the most enthusiastic believers don’t really belief in it. 

When it is too bad to believe, it probably isn’t. 

Besides, since perchlorate is, just as nitrate, also naturally found in many drinking water wells in the 

US, particularly in the west and centre of the country at levels about 1000 to 10,000 times 

higher(between 0.1 and 1 ppb) than this "new" level, one wonders then what effect should this have 

on the TH status of the millions of people in those areas if such much lower levels would have an 

effect already. 

Response: See response to comment ID 20772 under comment code 2200. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21042 

EPA Comment Code: 2200 

Comment: 1.3. A downstream effect implies an upstream effect 

Adding even more to this discrepancy was the fact that the NRC RfD was based on an effect 

upstream from the Blount study effect. 

Indeed since iodine uptake inhibition precedes any adverse health effect of perchlorate exposure 

including TH level change [see reference 1], perchlorate cannot have an effect on TH when there is 

no iodine uptake inhibition in the first place. This is the essence of the iodine uptake inhibition 

mechanism leading to a (potential) effect on TH levels. 

Unfortunately information about possible Iodine uptake inhibition into the thyroid at such low 

levels, while highly improbable as shown above, was not available from the NHANES data on 

which the Blount study was based. - Yet what we do know from those data is that there exists a 

strong relationship between those low levels of urinary (U) perchlorate and U iodine: for an increase 

of 1 ug/l U perchlorate, the U iodine levels increase linearly with about 30 ug/l all the way from the 

first to the ninth decile. So, even if perchlorate would have had a potential effect at such low levels it 

should have been more than compensated by the iodine association as this is what should be 

expected from a competitive uptake mechanism and because of the fact that the perchlorate 

inhibitive potency in relation to iodine is known to be around 1/30 based on in vitro studies [see 

reference 3] or 1/3 in a recent publication based on a in vivo study [see reference 4]. 

The scatter plot below [see reference 5] illustrates the strong relationship, all the way to the 9th 

percentile, of very low U perchlorate with U iodine in the U.S. population (NHANES 2001-2002) 

controlled for THs. 

[see figure in PDF docket ID EPA-HQ-OW-2008-0692-1990] 
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There may be even an explanation for this: perchlorate and iodine are both naturally present in all 

soils and low levels of perchlorate [see reference 6] and iodine are continuously formed in the 

atmosphere (just as the other halogens including iodine [see reference 7] and nitrate by the way). The 

complete disappearance of the relationship in the 9th percentile could be explained as the 

appearance of the higher level but less diffuse contaminant point sources of perchlorate on top of 

this natural background. 

- Further the same NHANES data show that U iodine is not related with (serum) TH [see reference 

8] which implies that the TH level changes observed seem to be caused by something that does not 

have anything to do with iodine levels and therefore with iodine uptake inhibition. If the TH levels 

found are independent from iodine U levels and therefore from the levels present in the diet then 

the downstream TH changes cannot be caused by an iodine uptake inhibitor such as perchlorate. If 

that still would be the case then iodine supplements should not be recommended for iodine 

insufficient individuals; again this does not have any sense. 

This association unfortunately was not discussed in the Blount paper as the population was split in 2 

groups based on their U iodine levels (this confirms that the mind was set on iodine uptake 

inhibition and not on any other mechanism, see next section). 

Response: See response to comment ID 29078 under comment code 2200 regarding the Blount et 

al. study. As discussed in the final determination, EPA believes that perchlorate may have an adverse 

effect on human health. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21043 

EPA Comment Code: 2200 

Comment: What other circumstantial evidence we have? 

What about some other covariates? 

1.4. Covariates that have been taken into consideration in the Blount study 

1.4.1. Relationships of other goitrogens with THs 

To be consistent, if the relationship of perchlorate with TH would be considered causal without any 

supportive evidence then the relationship of the other goitrogens with the same effect on iodide 

uptake and TH levels should be considered causal as well. 

1.4.1.1. Now in this study it was also found that increased levels of thiocyanate were significantly 

associated with decreased thyroid activity i.e. an unexpected opposite association compared with 

perchlorate’s association. Would that then mean that if this study were about investigating 

thiocyanate’s effect on TH (i.e. not focused on perchlorate) it would have to be concluded that it 

was now a remedy instead of a goitrogen and that for example consuming cassava would now be 
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good for fighting goitre? Since the opposite is known, this is further strong circumstantial evidence 

against the causal association. 

1.4.1.2. Also nitrate, also a known goitrogen with effect on iodine uptake and therefore, tested 

(controlled for) as a covariant as well, was significantly associated with T4 levels but only for women 

with iodine levels considered as sufficient ( =100 ug/l ) and not for those with levels considered as 

insufficient. Isn’t that contrary to the known mechanism associated with goitrogens as iodine uptake 

inhibitors? Or how can it be explained that sufficient becomes now insufficient and insufficient 

becomes now sufficient? 

Again the question can be raised: if this were instead a study on the goitrogenic effects of nitrate 

wouldn’t this association, if causal, preclude iodine supplements as a remedy and therefore also 

preclude iodine as a remedy against perchlorate and thiocyanate? We have not heard this and that 

would be unlikely and thus further undermines the causal hypothesis. 

1.4.1.3. This would then also be in direct conflict with the recommendations we have seen in 

relation with this study in that iodine insufficient individuals should increase the dietary intake of 

iodine to compensate for the alleged perchlorate effects. 

1.4.1.4. Moreover the fact that perchlorate was associated with T4 also for U iodine sufficient 

women all the way to the highest levels (besides for iodine insufficient women) would lead to the 

same contradiction. 

1.4.1.5. Most or all of the above statistically significant relationships could only be plausibly causal if 

the currently generally accepted knowledge about iodine and NIS (Sodium Iodine Symporter) 

goitrogens in association with the thyroid would be rejected. 

We have not found any author bringing forward this new hypothesis about the mechanism related to 

NIS either. 

This overwhelming direct and indirect evidence that the above relationships with other goitrogens 

could not be causal implies once again that attributing a cause-effect aspect to the perchlorate TH 

relationship because it happens to be in the "expected" direction, is arbitrary and unreasonable. 

Or said in other words, if all other relationships found are considered highly implausible to be 

causal, what can be the justification to single out one as causal because it seems to fit the 

"expectations" and explain away all the other relationships as "unclear" [see reference 2] since they 

do not fit those expectations? 

Response: See response to comment ID 29078 under comment code 2200. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21044 

EPA Comment Code: 2200 

Comment: 1.4.2. Levels of other goitrogens compared to perchlorate. 
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1.4.2.1. Thiocyanate compared to perchlorate The average U level of the goitrogen thiocyanate is 

1,200 ug/l which, after applying a potency equivalency of 1/15 [see reference 2,3], translates into 80 

ug/l perchlorate equivalency or 28 times more than the average perchlorate level of 2.8 ug/l. 

If 28 times more perchlorate equivalent does not show an association in the "expected" direction 

how could it be explained that 28 times less does? 

1.4.2.2. Nitrate compared to perchlorate The average U level of the goitrogen nitrate is 38,000 ug/l 

which, after applying a potency equivalency of 1/2402, 3, translates into 158 ug/l perchlorate 

equivalency or 56 times more than the average perchlorate level of 2.8 ug/l. 

If 56 times more perchlorate equivalent does not show an association in the "expected" direction as 

there is interaction with iodine levels but in the "wrong" direction, how could it be explained that 56 

times less does? 

It should be noted that the perchlorate potency compared to iodine has recently shown to be much 

weaker in vivo than in vitro yet the relative potency of the goitrogens compared to each other has 

been shown to remain unchanged [see reference 4]. 

Conclusion: Circumstantial evidence overwhelmingly concludes against the hypothesis. 

Response: EPA does not believe that sufficient data exist to permit comparison of the relative 

potency of perchlorate to other goitrogens, or to permit the conduct of a cumulative risk 

assessment. See response to comment ID 29078 under comment code 2200. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21045 

EPA Comment Code: 2200 

Comment: 2. The number and probability of possible alternative causes 

2.1. Why should those possible alternative causes have been considered with priority? 

Above we have discussed the goitrogens that have the same mode of action as perchlorate i.e. 

inhibition of iodine uptake thru NIS (sodium iodide symporter). 

There exist many other goitrogenic substances (which in effect are also goitrogens as they lead to the 

same endpoints) that have a different mode of action not related to iodine. 

The Blount study is about possible effects on THs of substances present in the population sample. 

So all known substances that affect TH levels should have been statistically tested and controlled for 

as well and not only those that act through the same mechanism as perchlorate. 
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Since as shown iodine levels are probably not relevant we should not look in the first place for 

something else that affects NIS function (and therefore potentially but only indirectly TH levels) but 

something that affects TH levels directly. 

EPA’s current RfD for perchlorate is based on perchlorate’s ability to inhibit the thyroid gland’s 

uptake of iodide by competing for the sodium (Na+)/iodide (I-) symporter (NIS), the protein 

responsible for transporting iodide into the thyroid gland for the purpose of synthesizing thyroid 

hormones. 

So it is surprising that EPA does not raise this issue but limits itself to mentioning nitrate and 

thiocyanate. If the Blount et al. study were about iodine uptake inhibition effect then this would 

have been justified. But it was not. It was about the downstream effect, the effect on TH. 

Yet in the Blount study it was assumed that iodine uptake inhibition was the upstream effect so 

much so that, as said, the population had been split into 2 groups, iodine deficient and iodine 

sufficient. As noted before, this only added more inconsistencies as it exposed additional 

"unexpected" relationships which should have been seen as an additional warning that something 

was amiss. 

Hence substances that have a direct effect on TH should have been tested with priority instead. 

Response: See response to comment ID 21044 under comment code 2200. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21046 

EPA Comment Code: 2200 

Comment: 2.2. Covariates that have not been taken into consideration in the study and should have 

been so with priority 

We quote from the January 2008 Thyroid journal: "Toxicological models and limited 

epidemiological studies have indicated that many organohalogen aromatic compounds, including 

dioxins, polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs), may be 

classified as â€ ̃â€ ̃endocrine disruptors, as they have the potential to alter normal thyroid function." 

"Because environmental exposures rarely occur singly, it is often difficult to disentangle a single 

exposure from other cooccurring environmental exposures and conditions that may confer risks 

upon children. Therefore, there is often the potential for confounding, in which both the exposure 

and the outcome under investigation are related to a third factor that may distort the observed 

exposure-disease relationship." "In epidemiologic studies, it is critically important to identify, 

measure, and control for such confounders." 

As mentioned, there are many widespread contaminants that are goitrogens with effects on TH 

levels via mechanisms unrelated to iodine uptake. 
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Some can be expressed as TEQ’s (total toxic equivalents) and include the known endocrine 

disruptors such as PCBs (polychlorinated biphenyls), PCDDs (polychlorinated dibenzo-pdioxins), 

PCDFs (polychlorinated dibenzofurans) besides PCDFs, PBDEs (polybrominated diphenyl ethers), 

DDE (dichlorodiphenyldichloroethylene) TCDDs (tetrachlorodibenzo-pdioxin), TBBPAs 

(Tetrabromobisphenol A), degradation products of DDT such as HCB (Hexachlorobenzene), etc. 

[see reference 9, 10 ,11] 

Most of them have a structure resembling thyroid hormones [see reference 12]. 

They act thru different mechanisms [see reference 13]. 

PCBs include 209 congeners that vary based on the number and positions of chlorine atoms. 

Compared with estrogens and antiandrogens, thyroid-disrupting chemicals are the least well studied 

endocrine disruptors (ED). It is therefore not surprising that few mixture studies exist using this 

kind of agents. 

Further many other substances with completely different structures are known goitrogens in the 

sense that they also affect directly or indirectly TH levels (see section 4). 

Question: Why weren’t these substances tested and controlled for as covariates to evaluate the 

independence of the perchlorate relationship, the more so that the data on some, such as PCBs and 

other dioxin-like substances, including those concerning pesticides, were available as they were 

included in the same 2001-2002 NHANES database from which perchlorate, iodine, the other 2 

NIS goitrogens and other 12 tested covariates were extracted? 

here were other hints that pointed to a different direction: While NHANES 2001-2002 THs levels 

do not reflect urinary iodine concentrations [see reference 5], serum PCBs, p,p'-DDE and HCB 

predict Thyroid Hormone Levels [see reference 14] and some do so in NHANES 2001-2002 as well 

[see reference 15] Also co variants such as smoking status which were associated with thiocyanate in 

the Blount study and follow-up studies [see reference 16] could just as well be linked to 

organohalogens as cause since tobacco contains organohalogen pesticides that are organohalogen 

based or transformed in such substances during burning [see reference 17]. 

Also why doesn’t EPA itself refer here to those critical covariates as they did in the EPA coauthored 

document: Moving Upstream: Evaluating Adverse Upstream Endpoints for Improved Risk 

Assessment and Decision-Making, EHP, 2008 and other EPA studies? [see reference 18, 19, 20]. 

Also reference [see reference 12] that dealt with perchlorate and PCBs as EDs together was research 

sponsored by an EPA grant. 

Why would for example investigating the effects on TH levels of a certain pesticide in soya without 

controlling for say isoflavones (see further below) or vice versa not be acceptable and why would it 

be in the case of perchlorate, particularly at such extremely low levels. 

Response: The hypothesis tested for in the Blount study was that there was a relationship between 

perchlorate and a limited number of other goitrogens, iodide status, and TSH/T4 concentration in 

the samples evaluated. The additional analyses noted by the commenter are beyond the scope of the 
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Blount study. EPA relies upon the best available peer reviewed data. See response to comment ID 

21049 under comment code 2200. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21047 

EPA Comment Code: 2200 

Comment: 2.3. The level found compared with the effect level 

The known threshold effect level on THs of organo halogens such as PCBs and other dioxin like 

substances that has an effect on THs has been found to be in the range of 0.1 to 10 ug /l serum 

depending on the substance [see reference 21]. 

The levels of those substances found in NHANES 2001-2002 is in this range and, as mentioned, a 

relationship of some with THs was found as well [see reference 15]. 

This is in stark contrast with the 4 orders of magnitude difference between the effect level of 

perchlorate on THs known from the body of the literature and the perchlorate levels that were 

related with THS found in the Blount study. 

This is illustrated by some scatter plots [see reference 5]: 

Scatterplot 1 and 2: the sum of 24 PCBs [see reference 5] has a similar relation with TSH as does 

perchlorate and for the same range of concentrations (The PCBs are concentrated at the left because 

of the detection limit). The 2 relationships are statistically significant. 

[see figures in PDF docket ID EPA-HQ-OW-2008-0692-1990] 

Response: EPA cannot evaluate calculations presented by the commenter that have not been peer 

reviewed. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21048 

EPA Comment Code: 2200 

Comment: 3. What then could be the link between perchlorate and those known endocrine 

disruptor. 

The most obvious and most widely spread common link is chlorine. On one hand it has been shown 

that chlorine based disinfectants such as those found in drinking water (DW) oxidize to perchlorate 

as a disinfection by-product (DBP). 
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This is for example the reason why Massachusetts doubled its MCL from 1 to 2 ppb because 

otherwise chlorination of DW and swimming pools with for example bleach would have to be 

curtailed. 

Is this oxidation of perchlorate from bleach (hypochlorite and hypochlorous acid) significant in 

comparison with daily intake of perchlorate? 

According to the Blount study (from the NHANES data) the average urinary perchlorate level in the 

population is 2.84ug/l which is roughly equivalent to an oral dose of 0.04 ug/kg-day. This 

corresponds with drinking water of 1.4 ppb. Massachusetts’ MCL was based on data that showed 

that about 0, 5 ppb perchlorate originated from bleach alone [see reference 22]. 

Therefore about 1/3 of the average daily intake of perchlorate would be due to bleach oxidation 

alone which is substantial and which shows that chlorine could be a significant source of 

perchlorate. 

Bleach is used ubiquitously as for example in water purification stations, paper mills, drinking water 

and for many other applications. 

Other potential sources of perchlorate as a DBP are other chlorine derivates such as chlorine gas 

and chloramine. 

On the other hand other DBPs originate from the reaction of chlorine based disinfectants with 

organic matter (waste) to form organochlorides [see reference 23]. 

What could be one of the possible pathways that link perchlorate to organochlorides such as PCBs 

via chlorine? 

According to EPA the building block for organochlorides is chlorophenol and chlorophenols are 

produced from the organic matter found in used water when it reacts with chlorinated disinfectants 

[see reference 24] (phenol is benzene with a hydroxyl group and PCBs are basically 2 chlorinated 

benzene rings). 

Those DBPs are found back in the drinking water leaving the water purification plants just as 

perchlorate when no special perchlorate removing devices are used which is the case most of the 

time in areas where only low levels are found. 

So this is one example of the link between very low levels of perchlorate and TH affecting 

substances: chlorine based disinfectants such as bleach, Cl2 and chloramines evolve to perchlorate 

on one side and to phenols, PCBS and other organochlorides including dioxin-like compounds on 

the other side. 

[Chloramines, besides being an added disinfectant, can also be formed as a reaction product of 

bleach with ammonia, itself amply present in used water [see ref 25]]. 

Response: EPA discussed the potential for perchlorate to be introduced into drinking water as part 

of the May 1, 2007 FR Notice. However, the source of perchlorate contamination is not a key factor 

in the determination under SDWA to regulate a contaminant. The presence of perchlorate in 
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disinfectants will be a factor evaluated by EPA as part of the treatment and technology evaluation 

for the proposed NPDWR for perchlorate. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21049 

EPA Comment Code: 2200 

Comment: Summary of chapter 3 

DBP road 1: Bleach/Cl2/Cl-/chloramine ->ClO-3 ->ClO-4 

DBP road 2: (in presence of organic (C) material): 

Bleach/ Cl2/Cl-/ chloramine ->phenols ->organochlorides/dioxins 

Since organo- chlorinated compounds are ubiquitous and since we find at least 1/3 of the total 

dietary perchlorate where we find organo-chlorinated compounds and since many of those have 

been shown to affect TH levels it is to be expected that low levels of perchlorate are associated with 

TH levels as found in the Blount et al study. 

Yet assigning cause to this association would be against all common sense as overwhelming 

circumstantial evidence shows in another direction. 

Perchlorate seems to be rather a marker, a witness, a messenger of the presence of ubiquitous 

goitrogenic contamination caused by the net effect of hundreds of substances (see also next section). 

This alternative explanation would on the same time eliminate any and all contradictions as listed 

from section 1.1. to 1.4.2.2 above. 

Response: EPA does not believe there are sufficient scientific data currently available to assess and 

characterize the combined risk of goitrogenic compounds. EPA has committed to a drinking water 

strategy that outlines four principles to expand public health protection for drinking water (USEPA, 

2010b). One of these principles is to address contaminants as groups. However, EPA does not 

believe that regulatory action to address perchlorate should be further delayed. Therefore, EPA 

intends to develop a proposed rule for perchlorate. At such time as a NPDWR is promulgated, EPA 

is required to review and revise, as appropriate, its drinking water standards at least every six years. 

Any revision must at least maintain or improve public health protection. When there are sufficient 

scientific data to assess the cumulative risks of perchlorate and other contaminants, EPA will review 

this information to evaluate whether any revisions of NPDWRs are appropriate. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21050 
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EPA Comment Code: 2200 

Comment: 4. Would this be the final answer: organochlorides are the sole cause of the (slight) TH 

changes? 

Probably not. 

The fact that in the NHANES 2001-2002 database organochlorides are cross- sectionally associated 

with THs and, contrary to perchlorate, at levels that are consistent with known effect levels and, 

contrary to perchlorate, that this does not occasion related inconsistencies if the relationship would 

be seen as cause effect, still does not mean it is so. 

What we only can say at this point is that the chance that those contaminants are at least partially the 

cause is much higher than for perchlorate. 

There seems to be a ubiquitous contaminant pool in which there are all kinds of goitrogens acting 

with all kind of mechanisms that influence TH levels and thyroid function. 

Somehow they could be all linked together. 

Following an example of such a link: 

When bromides are used as disinfectant also organobromides are formed [see reference 21]. 

When bromine and chlorine is involved, halogenated furanones can be produced in drinking water 

by the reaction of naturally occurring organic matter and bromide with the disinfectant chlorine and 

chloramine. Research on their concentrations in drinking water is at an early stage and they are not 

regulated by EPA: http://pubs.acs.org/cen/news/86/i13/8613news7.html 

[Clarification: A furanone is a furan where the H is substituted with Cl, becoming polychlorinated 

furanones or polychlorinated dibenzofuranones. A furan is short for dibenzofuran; a chlorinated 

dibenzofuran is a PCB with a furan ring in the middle] 

So the halogen bromine can join the second pathway for chlorine: Bleach/Cl2/ Cl2/Cl-/ 

chloramine, bromides ->furanones or phenols ->organohalogens/dioxins 

This can be illustrated again thru NHANES data plots: 

Scatterplot 3 and 4 [see reference 5]: the organobromide PDE (polybrominated diphenyl ethers) has 

a similar relation with TSH as does perchlorate and for the same range of concentrations. The 2 

relationships are statistically significant. Thus organochlorides, organobromides and perchlorate 

seems to be related with each other within the goitrogenic pool. 

[see figures in PDF docket ID EPA-HQ-OW-2008-0692-1990] 

Some components of this goitrogenic contaminant pool have a stimulatory or agonistic effect, 

others an inhibitory or antagonistic effect [see reference 26, 27]. Some do not have any effect at all at 

environmental doses. 
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This may explain why in cross sectional studies as those based on the NHANES data base the effect 

of the sum of some PCBs apparently is not always greater than each individual effect as would be 

expected [see reference 28] as each individual PCB on itself can be linked to other non identified 

and quantified goitrogens i.e. (once again) not controlled for covariates with opposite effects. 

As mentioned, already there exist 209 known congeners of PCBs alone. They vary based on the 

number and positions of chlorine atoms but also on their effect (strength and direction). 

Many have not even been studied on their goitrogenic effect. 

Even different groups of chemicals with different mechanism could have synergetic or antagonistic 

effects [see reference 29]. 

Others may be linked to each other in certain environments and not in others. 

Going back to the example above: Polychlorinated Biphenyls (PCBs) and Polybrominated Diphenyl 

Ethers (PBDEs) (both also called polyhalogenated phenolic compounds) may have a cumulative 

effect where bromine and chlorine based disinfectants are used (for example for swimming pools) 

and end up as DBPs (disinfection byproducts) in drinking water after having gone thru the 

purification plant. This link could not exist in places where one of both is not used. 

Other goitrogenic phenols, such as Bisphenol A, linked itself to polyvinylchloride (PVC) such as 

used in waterpipes, may be linked to this chloride and halogen pool. On the other side completely 

different types of goitrogens, even natural ones, could be linked indirectly to the pool as well: for 

example organohalogen based pesticides may be present in very low amounts in soybeans but the 

goitrogenic effect could instead be primarily due to the isoflavones naturally present in soymilk [see 

reference 30] or the thiocyanates present in rape or broccoli or other natural goitrogens such as 

genistein, resveratrol, silymarin, linuron [see reference 24]. 

Also fluorine is considered a goitrogen [see reference 31]. So, adding fluorine in salt for dental 

purposes could partially neutralise the effect of added iodine. Adding fluorine, another halogen, in 

drinking water, which is also common, would then on itself be linked to perchlorate and the 

organohalogen DBPs. 

Further fluorine is a major constituent of phosphate fertilizers [see reference 32] and is taken up by 

the crop so it could, just as the goitrogenic pesticides and isoflavones, be part of the goitrogenic 

pool as well. Also iodine itself, the fourth halogen, is used as a disinfectant. 

Other factors, even the most unexpected (birth delivery mode) may confound the effects [see 

reference 33]. 

So it seems plausible that perchlorate is a marker, but only marker, of this ubiquitous pool of thyroid 

function affecting contaminants which means that the more perchlorate is found (outside from the 

point source contaminations of course) the more goitrogenic the pool will be via the chlorine and 

halogen link and therefore the more goitrogenic effect on THs will be seen. 
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The answer to the question of what caused the Thyroid hormone changes in the Blount study is: all 

of the above except perchlorate as seen at those very low levels. 

Response: See response to comment ID 21049 under comment code 2200. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1990 

EPA Comment ID: 21051 

EPA Comment Code: 2200 

Comment: It may be felt as politically rewarding to look for a simple explanation but, from what 

precedes, such a simplistic and irrational interpretation would certainly not lead to effective health 

protective measures. On the contrary it would lead to a feel good situation with only illusory effects. 

A careful analysis should precede any sweeping statements like those we are seeing in the media. We 

hear a lot about holistic approaches in health risk assessment but not many practical applications. 

This may be one of them. 

______________________________________________ 1 National Academy of 

Sciences/National Research Council. Health Implications of Perchlorate Ingestion. National 

Academy Press. Washington, DC. 2005. 

2 Benjamin C. Blount, James L. Pirkle, John D. Osterloh, Liza Valentin-Blasini, and Kathleen L. 

Caldwell. Urinary Perchlorate and Thyroid Hormone Levels in Adolescent and Adult Men and 

Women Living in the United States. Environmental Health Perspectives. December 2006, Volume 

114, Number 12. 

3 Tonacchera M., Pinchera A., Dimida A., Ferrarini E., Agretti P., Vitti P., Santini F., Crump K., 

Gibbs J. Relative Potencies and additivity of perchlorate, thiocyanate, nitrate, and iodide on the 

inhibition of radioactive iodide uptake by the human sodium iodide symporter. Thyroid 14: 1012-

1019. 2004. 

De Groef B., Decallonne BR., Van der Geyten S., Darras VM., Bouillon R. Perchlorate versus other 

environmental sodium/iodide symporter inhibitors : potential thyroid-related health effects. 

European Journal of Endocrinology. 2006, 155: 17-25. 

4 Dasgupta PK., Kirk AB, Dyke JV, Ohira S-I. Intake of iodine and perchlorate and excretion in 

human milk. Environmental Science & Technology. 2008, 42: 8115-8121. 

5 Charnley G. Perchlorate: Overview of Risks and Regulation. Food and Chemical Toxicology. 

2008. Some graphs shown above and related to this study were obtained from the Statistical 

Department of the Catholic University of Leuven, Belgium. 

6 Dasgupta PK, Martinelango PK, Jackson WA, Anderson TA, Tian K, Tock RW, et al. The origin 

of naturally occurring perchlorate: the role of atmospheric processes. Environ Sci Technol. 2005. 

39:1569-1575. 
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7 KÃ1⁄4pper F.C., Carpenter L. J., McFiggans G. B.,. Palmer C. J., Waite T. J., Boneberg E.-M., 

Woitsch S., Weiller M., Abela R., Grolimund D., Potin P., Butler A., Luther G. W., Kroneck P. M. 

H., Meyer-Klaucke W., Feitersm M. C.. Iodide accumulation provides kelp with an inorganic 

antioxidant impacting atmospheric chemistry. The National Academy of Sciences of the USA. 

Environmental Sciences. 2008. 

Baker A. R, Tunnicliffe C. Jickells T. D. Iodine speciation and deposition fluxes from the marine 

atmosphere. Journal of geophysical research. ISSN 0148-0227. 2001. 

Von Glasow R. Seaweed, Iodine, New Particles and Atmospheric Chemistry - The Current State of 

Play. Institute of Environmental Physics, Im Neuenheimer Feld 229, University of Heidelberg, 

69120 Heidelberg, Germany. Email: roland.von.glasow@iup.uni-heidelberg. 2005. 

8 Soldin OP, Tractenberg RE, Pezzullo JC. Do thyroxine and thyroid-stimulating hormone levels 

reflect urinary iodine concentrations? Therapeutic Drug Monitoring. 2005, 27: 178-185. 

9 Brucker-Davis F. Effects of environmental synthetic chemicals on thyroid function.Thyroid. 1998, 

8: 827-826. 

10 McLanahan ED Campbell JL Jr, Ferguson DC, Harmon B, Hedge JM, Crofton KM; Mattie DR, 

Braverman L, Keys DA, Mumtaz M, Fisher JW. Low-dose effect of ammonium perchlorate on the 

hypothalamic-pituitary-thyroid (HPT) axis of adult male rats pretreated with PCB 126. Toxicological 

Sciences. 2007, 97: 308-317. 

11 Tallsness CE, Kuriyama SN, Sterner-Kock A, Schnitker P. Grande SW, Shakibaei M., Andrade A, 

Grote K, Chahoud I. In utero and lactational exposures to low doses of polybrominated diphenyl 

ether-47 alter the reproductive system and thyroid gland of female rat offspring. Environmental 

Health Perspectives (in press/online). 2007. 

12 Zoeller R.T., Presentation (year unknown) : Low-Dose Effects of Thyroid Toxicants on 

Neurodevelopment , year unknown) , funded by US EPA grant nr.RD83213701. 

13 Wataru Miyazaki, Toshiharu Iwasaki, Akira Takeshita, Chiharu Tohyama, Noriyuki Koibuchi. 

Identification of the Functional Domain of Thyroid Hormone Receptor Responsible for 

Polychlorinated Biphenyl-Mediated Suppression of Its Action In Vitro. Environmental Health 

Perspectives. September 2008, Volume 116, Number 9. 

Chris E. Talsness, Sergio N. Kuriyama, Anja Sterner-Kock, Petra Schnitker, Simone Wichert 

Grande, Mehdi Shakibaei, Anderson Andrade, Konstanze Grote, Ibrahim Chahoud. Utero and 

Lactational Exposures to Low Doses of Polybrominated Diphenyl Ether-47 Alter the Reproductive 

System and Thyroid Gland of Female Rat Offspring. Environmental Health Perspectives. March 

2008, Volume 116, Number 3. 

Andreas Kortenkamp. Ten Years of Mixing Cocktails: A Review of Combination Effects of 

Endocrine-Disrupting Chemicals. Environmental Health Perspectives. December 2007. Volume 

115, Number S-1. 
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14 John D. Meeker, Larisa Altshul, Russ Hauser. Serum PCBs, p,p'-DDE and HCB predict Thyroid 

Hormone Levels in Men. Environ Res. 2007 June; 104(2): 296-304. 

15 Mary E. Turyk, Henry A. Anderson, Victoria W. Persky. Relationships of Thyroid Hormones 

with Polychlorinated Biphenyls, Dioxins, Furans, and DDE in Adults. Environmental Health 

Perspectives. August 2007, Volume 115, Number 8. 

16 Craig Steinmaus, Mark D. Miller, Robert Howd. Impact of Smoking and Thiocyanate on 

Perchlorate and Thyroid Hormone Associations in the 2001-2002 National Health and Nutrition 

Examination Survey. Environmental Health Perspectives. September 2007, Volume 115, Number 9. 

17 Julie B. Herbstman, Andreas SjÃ¶din, Benjamin J. Apelberg, Frank R. Witter, Donald G. 

Patterson Jr., Rolf U. Halden, Richard S. Jones, Annie Park, Yalin Zhang, Jochen Heidler5 Larry L. 

Needham, Lynn R. Goldman. Determinants of Prenatal Exposure to Polychlorinated Biphenyls 

(PCBs) and Polybrominated Diphenyl Ethers (PBDEs) in an Urban Population. Environmental 

Health Perspectives. December 2007, Volume 115, Number 12. 

18 Tracey J. Woodruff, Lauren Zeise, Daniel A. Axelrad, Kathryn Z. Guyton, Sarah Janssen, Mark 

Miller, Gregory G. Miller, Jackie M. Schwartz, George Alexeeff, Henry Anderson, Linda Birnbaum, 

Frederic Bois, Vincent James Cogliano, Kevin Crofton, Susan Y. Euling, Paul M.D. Foster, Dori R. 

Germolec, Earl Gray, Dale B. Hattis, Amy D. Kyle, Robert W. Luebke, Michael I. Luster, Chris 

Portier, Deborah C. Rice, Gina Solomon, John Vandenberg, R. Thomas Zoeller. Meeting Report: 

Moving Upstream-Evaluating Adverse Upstream End Points for Improved Risk Assessment and 

Decision-Making. November 2008. Environmental Health Perspectives Volume 116, Number 11. 

19 US Environmental Protection Agency (US EPA). Exposure and Human Health Reassessment of 

2,3,7,8- Tetrachlorodibenzo-p-Dioxin (TCDD) and Related Compounds National Academy 

Sciences (NAS) Review Draft. National Center for Environmental Assessment. Office of Research 

and Development. Washington, DC. 2004. Page 14 

20 US Environmental Protection Agency (US EPA). Framework for Cumulative Risk Assessment. 

EPA/630/P- 02/001F. National Center for Environmental Assessment. Office of Research and 

Development. Washington, DC. 2003a. Available at 

http://cfpub.epa.gov/ncea/raf/recordisplay.cfm?deid=54944 

21 Johan Maervoet, Griet Vermeir, Adrian Covaci, Nicolas Van Larebeke, Gudrun Koppen, Greet 

Schoeters, Vera Nelen, Willy Baeyens, Paul Schepens, Maria K. Viaene. Association of Thyroid 

Hormone Concentrations with Levels of Organochlorine Compounds in Cord Blood of Neonates. 

Environmental Health Perspectives. December 2007, Volume 115, Number 12. 

Jonathan Chevrier, Brenda Eskenazi, Asa Bradman, Laura Fenster, Dana B. Barr. Associations 

between Prenatal Exposure to Polychlorinated Biphenyls and Neonatal Thyroid-Stimulating 

Hormone Levels in a Mexican-American Population, Salinas Valley, California. Environmental 

Health Perspectives. October 2007. Volume 115, Number 10. 

Lawrence M. Schell, Mia V. Gallo, Melinda Denham, Julia Ravenscroft, Anthony P. DeCaprio, 

David O. Carpenter. Relationship of Thyroid Hormone Levels to Levels f Polychlorinated 
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Biphenyls, Lead, p,pÂ ́- DDE, and Other Toxicants in Akwesasne Mohawk Youth. Environmental 

Health Perspectives. June 2008, Volume 116, Number 6 

Lesa L. Aylward, Julie E. Goodman, Gail Charnley, Lorenz R. Rhomberg. A Margin- of-Exposure 

Approach to Assessment of Noncancer Risks of Dioxins Based on Human Exposure and Response 

Data. Environmental Health Perspectives. October 2008. Volume 116, Number 10. 

June-Soo Park, Linda Linderholm, M. Judith Charles, Maria Athanasiadou, Jan Petrik, Anton Kocan, 

Beata Drobna, Tomas Trnovec, Ã...ke Bergman, Irva Hertz- Picciotto. Polychlorinated Biphenyls 

and Their Hydroxylated Metabolites (OH- PCBs) in Pregnant Women from Eastern Slovakia. 

Environmental Health Perspectives Volume. January 2007, 115, Number 1. 

22 Massachusetts Department of Environmental Proctection. Perchlorate: Draft Toxicological 

Profile and Health Assessment. 2004. 

23 Gary A. Boorman, Vicki Dellarco, June K. Dunnick, Robert E. Chapin, Sid Hunter, Fred 

Hauchman, Hank Gardner, Mike Cox, and Robert C. Sills. Drinking Water Disinfection Byproducts: 

Review and Approach to Toxicity Evaluation. Environmental Health Perspectives Supplements, 

February 199, Volume 107, Number S1. 

24 Environmental Protection Agency, EPA/600/P-03/002F).An Inventory of Sources and 

Environmental Releases of Dioxin-Like Compounds in the United States for the Years 1987, 1995 

and 2000. Federal Register: December 1, 2006 (Volume 71, Number 231)] Page 69564-69565] 

Glinda S. Cooper, Samantha Jones. Pentachlorophenol and Cancer Risk: Focusing the Lens on 

Specific Chlorophenols and Contaminants. National Center for Environmental Assessment, U.S. 

Environmental Protection Agency, Washington, DC, USA. Received 16 November 2007; accepted 

10 April 2008. 

25 John Tibbetts. What's in the Water: The Disinfectant Dilemma. Environmental Health 

Perspectives. Volume 103, Number 1, January 1995. 

http://content.nejm.org/cgi/content/extract/341/11/848-a 

http://www.erj.ersjournals.com/cgi/content/full/19/5/790 

26 Cornelia Schmutzler, Inka Gotthardt, Peter J. Hofmann, Branislav Radovic, Gabor Kovacs, Luise 

Stemmler, Inga Nobis, Anja Bacinski, Birgit Mentrup, Petra Ambrugger, Annette GrÃ1⁄4ters, Ludwik 

K. Malendowicz, Julie Christoffel, Hubertus Jarry, Dana SeidlovÃ -Wuttke, Wolfgang Wuttke, Josef 

KÃ¶hrle. Endocrine Disruptors and the Thyroid Glandâ€”A Combined in Vitro and in Vivo 

Analysis of Potential New Biomarkers. Environmental Health Perspectives. December 2007, 

Volume 115, Number S-1. 

27 http://www.ourstolenfuture.org/Basics/chemlist.htm 

28 Kevin M Crofton, Elena S Craft, Joan M Hedge, Chris Gennings, Jane E Simmons, Richard A 

Carchman, W Hans Carter Jr, Michael J Devito. Thyroid-hormone- disrupting chemicals: evidence 

for dose-dependent additivity or synergism. Neurotoxicology Division, National Health and 

Environmental Effects Research Laboratory, Office of Research and Development, U.S. 
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Environmental Protection Agency, Research Triangle Park, North Carolina, USA. Environ Health 

Perspect. 2005 Nov ;113 (11):1549-54 16263510 (P,S,G,E,B) 

29 Andreas Kortenkamp. Ten Years of Mixing Cocktails: A Review of Combination Effects of 

Endocrine-Disrupting Chemicals. Environmental Health Perspectives, December 2007, Volume 

115, Number S-1. 

30 Daniel R. Doerge, Daniel M. Sheehan. Goitrogenic and Estrogenic Activity of Soy Isoflavones. 

Environmental Health Perspectives Supplements. June 2002, Volume 110, Number S3. 

31 Fluoride in Drinking Water: A Scientific Review of EPA's Standards (NAS, 2006) 

http://www.iicph.org/docs/water-reg-20060830.htm 

http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=476957 

32 http://fluoridealert.org/phosphate/overview.htm#2 

33 Julie B. Herbstman, Andreas SjÃ¶din, Benjamin J. Apelberg, Frank R. Witter, Rolf U. Halden, 

Donald G. Patterson Jr., Susan R. Panny, Larry L. Needham, and Lynn R. Goldman. Birth Delivery 

Mode Modifies the Associations between Prenatal Polychlorinated Biphenyl (PCB) and 

Polybrominated Diphenyl Ether (PBDE) and Neonatal Thyroid Hormone Levels. Environmental 

Health Perspectives. October 2008, Volume 116, Number 10. 

Response: See response to comment code 2200. SDWA requires EPA to rely upon the best 

available peer reviewed science in establishing a NPDWR. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21066 

EPA Comment Code: 2200 

Comment: iv. Blount et al. (2006; cited at Blount et al., 2006b in the EPA Notification) 

Using the NHANES 2001-2002 data set and a cross-sectional study design, this study reports 

measurement of urinary perchlorate, urinary iodide, serum TSH, and serum total T4 levels in men 

and women over the age of 12. The 2001-2002 NHANES data provide the largest group of subjects 

to date from which sampling data can be derived. The authors report that perchlorate levels were 

not associated with total T4 or TSH levels in men, but were a negative predictor of total T4 and a 

positive predictor of TSH in women with urinary iodine less than 100 ug/L. They report that in 

women with urinary iodine greater than 100 ug/L, urinary perchlorate was a positive predictor of 

TSH, but not associated with T4. The significance of evaluating women with urinary iodide less than 

100 ug/L is based on the WHO statement that a median urinary iodine concentration for the entire 

population, based on spot samples of less than 100 ug/L is indicative of overall iodine deficiency for 

that population (WHO 2004). 

This study has drawn a great deal of attention as it appears-to the average audience-to demonstrate 

an "effect" of perchlorate, albeit at exposures below those which cause any measurable inhibition of 
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iodide uptake. However, there are a number of considerations that should be noted that to better 

understand the significance of the data reported. 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21068 

EPA Comment Code: 2200 

Comment: Second, it is important to understand what the methods inherent to scientific research 

are. For example, knowing what is meant by "statistical significance and "clinical significance." A 

"statistically significant" difference simply means it is unlikely that there is a difference between two 

variables (e.g., numbers) that is due to chance. With a well designed experimental study, statistical 

significance can be extremely important. However, statistical significance is also a function of sample 

size, variability in the variables measured, etc. Statistical significance does not necessarily mean the 

difference is large, important, or biologically significant. However, for biological data, we are keenly 

interested if something is statistically significant is it also clinically significant, that is is there change 

in the variable or parameter that is large enough to affect a clinical or medical condition (e.g., 

development of hypothyroidism). Blount et al., 2006 report statistically significant variables, but do 

not report any variables with clinical significance. 

This type of study conducted by Blount and his colleagues cannot determine causation, only 

association between the variables studied (Wartenberg and Buckler, 2001). If important variables are 

missing, then spurious conclusions can be made. Thus, without a full set of variables measured, 

including a consistent urinary iodide measurement, any association should be examined carefully for 

reliability. 

Furthermore, perchlorate did not actually lower (or was even associated with) thyroid hormones 

outside the normal range of values. Even if it had, the NRC committee does not think that 

"...transient changes in serum thyroid hormones or TSH concentrations are adverse health effects; 

they are simply biochemical changes that might precede adverse effects" (NRC, 2005). 

The study was considered by ATSDR; however, ATSDR states, "limitations of the study 

acknowledged by the investigators include those common to cross-sectional analyses, the 

assumption that urinary perchlorate correlate with levels in the thyroid stroma and tissue, and the 

measurement of total T4 rather than free T4" (ATSDR, 2008). 

Third, any study must have careful consideration for the parameters and variables that are measured 

or available. The purpose of NHANES is designed to collect information about the health and diet 

of people in the United States. It is a survey for a broad range of possible diseases related to diet and 

health. While it obtains parameters for thyroid function, those parameters fall far short of the 

parameters needed to clearly understand thyroid health. For example, there were only two measures 

of thyroid function (total T4 and TSH) in the NHANES dataset used in this study; NHANES 

currently uses spot urine samples for iodide status which are neither the preferred, nor most reliable, 

measure of urinary iodide (Barr et al. 2005); there was lack of normalization for the dilution of 

individual urine samples using urinary creatinine levels; and due to restraints of the NHANES 
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database, the authors were not able to note the incidence of autoimmune thyroiditis, the most 

common thyroid disorder in the U.S., which causes changes in serum T4, T3, and TSH 

concentrations due to errant immune mechanisms attacking the thyroid gland (NRC, 2005). A 

complete assessment produced by Intertox is attached as Appendix A. In the appendix, there is a 

more thorough discussion regarding the use of spot urine testing, confounders, and use of the 

available NHANES variables to drawn conclusions. 

This study did not present urinary measures normalized to creatinine. The concentration of 

dissolved substances in urine, such as iodide, may vary between individuals or between samples from 

the same individual. Normalization with creatinine is not a perfect method, but is commonly used to 

account for this variability (Furnee et al. 1994). 

Response: No response is required for the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21069 

EPA Comment Code: 2200 

Comment: At a recent symposium on perchlorate held in conjunction with the annual Society of 

Toxicology (SOT) meeting in Seattle, Lamm et al. (2008) presented their initial reanalysis of the 

NHANES dataset used by Blount et al. with an adjustment for urinary creatinine. Lamm et al. 

considered a subset of women from the Blount et al. study who were of childbearing age (15-44 

years old; the Blount et al. study group included all women over the age of 12) as well as the 

interaction of thiocyanate and nitrate, both in urine. They found there was no significant association 

between perchlorate and total T4, even for women with urinary iodide less than 92 ug/g (Figure 2). 

They did find a significant association for women with urinary iodide greater than 163.7 ug/L for 

both perchlorate and thiocyanate. 

[Figure 1. Urinary Reanalysis Results of the NHANES Data - See PDF Docket ID EPA-HQ-OW2008-0692-1855] 

Response: No response is required to the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21071 

EPA Comment Code: 2200 

Comment: The American Thyroid Association (ATA) issued a public health statement cautioning 

against the paper's use in making decisions on regulating perchlorate. The ATA noted that "serum 

thyroxine was measured as total thyroxine rather than as free thyroxine, the most frequently used 

clinical measurement and the physiologically available form of thyroxine. Thyroid autoantibodies, an 

important confounder in thyroid physiology, have not yet been measured. These have an especially 

high prevalence in women and may have contributed to the reported correlations. The presence of 
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potentially confounding pharmaceutical and medical factors, such as estrogen use or autoimmune 

thyroid disease, was not used as a basis for exclusion from the analysis. Inclusion of laboratory 

results from multiple laboratories may need to be more carefully considered. The reason that 

perchlorate, but no other measured goitrogen studied, influenced thyroid function at low urinary 

levels of iodine is not explained. The development of further laboratory information is necessary 

before the implications of the findings can be understood. The issues raised are important and 

additional study to resolve them should be pursued" (ATA, 2006). 

Fourth, not only were the thyroid hormone values within normal clinical ranges, but urinary 

perchlorate levels as a surrogate for dose demonstrate that these perchlorate exposures are well 

below the threshold for zero inhibition of iodide uptake, a non-adverse effect. Exposures that are 

below the threshold for iodine uptake inhibition are below the NOEL for perchlorate and are not 

adverse (NRC, 2005; Greer et al., 2002). 

Finally, taken from the premise that science is incremental and knowledge builds collectively over 

time, concerns raised by scientists related to the Blount et al. study should be considered an 

opportunity for further study. According to Dr. Benjamin Blount, a new study will be conducted 

using a new data set, NHANES 2007, and will include obtaining data for eight variables of thyroid 

function (total T4, free T4, total T3, free T3, thyroid globulin, anti-thyroid peroxidase, anti-thyroid 

globulin, and TSH).[FN5: Personal Communication between Dr. Richard Pleus and Dr. Benjamin 

Blount. September 22, 2008.] Furthermore, recognizing that urinary spot iodine or single point 

iodine measures are not a good indicator of iodine status, a different approach is being considered. 

We believe more research should be conducted to better understand the results of this study. 

Response: No response is needed to the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21072 

EPA Comment Code: 2200 

Comment: Steinmaus et al. (2007) used the same dataset as Blount et al. to assess the correlation 

between smoking, thiocyanate and urinary perchlorate, and thyroid hormone levels. Using the same 

NHANES data set, it is not surprising that many of the same results were noted. Many of the same 

methodological issues reported for Blount et al. apply to this study. As in Blount et al., they did not 

find any interaction between perchlorate and smoking and TSH or total T4 in women with urinary 

iodine levels greater than or equal to 100 ug/L or in men. They did conclude that in women with 

urinary iodine less than 100 ug/L, perchlorate increased the risk of lower total T4 and greater TSH, 

just as was reported in the Blount et al. study. This association was stronger when the woman was 

also a smoker or had high urinary thiocyanate levels. 

Both Blount et al. and Steinmaus et al. (2007) show an association between exposures to low, 

environmentally-relevant levels of perchlorate and non-adverse reductions in thyroid hormones that 

remain within the normal ranges. However, these studies contradict the wide body of direct studies 

showing no effect even at low levels. These studies are valuable in that they test a large population; 

however, neither study shows that exposure to perchlorate at environmentally relevant doses causes 

an adverse health effect, even in a sensitive population. 
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Response: See response to comment ID 29078 under comment code 2200. As discussed in the 

final perchlorate regulatory determination and elsewhere in the response to comments document, 

EPA believes that perchlorate may have an adverse effect on the health of persons. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21073 

EPA Comment Code: 2200 

Comment: v. Blount et al. (2007) 

Blount and colleagues used the NHANES urinary perchlorate data to estimate the total daily dose 

for adults. These data were adjusted for creatinine. The estimated 95th percentile dose was 0.234 

ug/kg-day with a confidence interval of 0.202 - 0.268 ug/kg-d. They also reported that perchlorate 

was measurable in all of the samples they tested and the urinary levels were higher in children 

compared to adults. The estimated doses reported here were lower than the RfD and below the level 

of inhibition of iodide uptake. The NRC states that "...inhibition of iodide uptake by the thyroid 

clearly is not an adverse effect; however if it does not occur, there is not progression to adverse 

health effects" (NRC, 2005). 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21080 

EPA Comment Code: 2200 

Comment: APPENDIX A 

Review of Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell KL. 2006. 

Urinary perchlorate and thyroid hormone levels in adolescent and adult men and women living in 

the United States. Environmental Health Perspectives 114(12):1865-71. 

A number of scientific issues related to the experimental design of the NHANES dataset and the 

Blount et al. (2006) analysis make drawing meaningful conclusions from the data extremely difficult. 

Many of these issues are discussed below, although this list is not exhaustive. 

In their paper, Blount et al. (2006) examined the relationship between urinary levels of perchlorate 

and serum levels of thyroid stimulating hormone (TSH) and total thyroxine (T4) in men and women, 

aged 12 and older, participating in the NHANES during 2001-2002. They made the following 

primary observations: 

* Perchlorate was not a significant predictor of total T4 or TSH levels in men. 
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* For women with spot urinary iodine concentrations < 100 ug/L, perchlorate was a significant 

negative predictor of total T4 (p < 0.0001) and a positive predictor of TSH (p = 0.001). 

* For women with urinary iodine >= 100 ug/L, perchlorate was a significant positive predictor of 

TSH (p = 0.025), but not total T4 (p = 0.550). 

To assess the reliability of these conclusions, we reviewed the Blount et al. (2006) paper and the 

NHANES 2001-2002 dataset (CDC 2006) used by the authors. We reviewed the same variables 

reported in the paper and several dozen other variables not reported in the paper but reported in the 

NHANES 2001-2002 dataset. 

The data collected by NHANES is a survey and not a true epidemiological or clinical study. In 

epidemiological and clinical studies, effort is made to design the study to control for all variables 

except the variables in question. Surveys are not designed in this manner-their purpose is to collect 

data from a large number of people over a period of time. NHANES is designed to assess the health 

and nutritional status of adults and children in the United States (U.S.), combining interviews and 

physical examinations. It is a major program of the National Center for Health Statistics (NCHS), 

which is part of the Centers for Disease Control and Prevention (CDC) of the U.S. Public Health 

Service, and has the responsibility for producing vital health statistics for the nation (CDC, 2006). 

NHANES 2001-2002 was designed to continue the collection of information about the health and 

diet of people in the U.S. that was begun with earlier surveys to fulfill specific goals. These include 

estimating the number and percent of persons in the general U.S. population and designated 

subgroups with selected diseases and risk factors; monitoring trends in the prevalence, awareness, 

treatment, and control of select diseases; monitoring trends in risk behaviors and environmental 

exposures; studying the relationship between diet, nutrition, and health; and exploring emerging 

public health issues. 

Response: No response is needed for the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21081 

EPA Comment Code: 2200 

Comment: Key components to designing a thyroid study 

When conducting a thyroid study, a number of key variables should be considered that are not 

necessarily included when collecting data for a survey such as NHANES. For instance, thyroid 

hormone and TSH levels can vary substantially during the day. Free T4 (not total T4, which was 

measured in NHANES) is the most important thyroid parameter for assessing hypothyroidism. 

Because hypothyroidism is most commonly caused by one's own immune system, parameters used 

to assess this effect (including serum antibodies to thyroglobulin and thyroid peroxidase) should also 

be measured (but were not in the NHANES study). In general, the use of NHANES data to draw 

conclusions regarding exposures is controversial because of "...the utility of these data to address an 
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existing public health concern, including investigation of etiology, instead of undertaking a study that 

includes original data collection" (Wartenberg and Buckler, 2001). 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21082 

EPA Comment Code: 2200 

Comment: Study variables of concern 

We were able to confirm the dataset Blount et al. (2006) used in the paper and generally replicate the 

statistical results obtained by Blount et al. This allows us to examine the experimental design of the 

study with more confidence. Based on our review, we observed several key variables that caused us 

to question the conclusions presented in the Blount et al. paper. These variables are summarized 

below.[FN10: This evaluation is primarily based on the sample of 1,111 women aged 12 and older 

(i.e., the "study group"), described by Blount et al., from whom urine samples for perchlorate and 

serum thyroid hormone/TSH concentrations were measured, and excluding those who had a 

reported history of thyroid disease, were taking thyroid medications or a small subset of other 

thyroid- active drugs, or had extreme (high) levels of TSH or extreme (low) levels of T4. It should 

also be noted that total T4 measurements were performed at two separate laboratories which may 

have introduced some bias.] 

Relying upon the urinary iodide measurements for classification of study subjects into "low" or 

"high" iodine groups is not scientifically appropriate. 

* Urinary iodine concentrations in the study group ranged from 6 to 136,161 ug/L. The geometric 

mean was 127 ug/L (SE = 5.4) and the 5th and 95th percentiles were 22 and 568 ug/L, respectively. 

Our findings for this group are consistent with the summary of urinary iodine measurements in 

NHANES 2001-2002 published by the CDC (Caldwell et al., 2005). If taken at face value as 

representative of chronic iodine nutrition, the upper limits of these measurements likely exceed safe 

levels and should be a source of some alarm for the CDC. For example, elevated TSH levels and 

hypothyroidism have been associated with daily iodine intakes in excess of 750 ug/day by adults 

(NAS 2001). However, these measurements were taken in spot samples and are thus not necessarily 

indicative of an individual's iodine status. 

* Urinary creatinine concentrations were highly variable from subject to subject (range 9 to 774 

ng/mL), indicating significant differences in sample dilution and, likely, urinary output. 

* The WHO has stated that a median urinary iodine concentration within a population, based on 

spot samples of <100 ug/L is indicative of iodine deficiency within the population (WHO, 2004). 

The median urinary iodine concentration for the study population evaluated by Blount et al. (n 

=1,111) is 133 ug/L. Thus, assuming that iodine deficiency exists within this population is 

inappropriate- the WHO criteria are not meant to diagnose iodine deficiency in individuals (Borak, 

2005). Conversely, the best way to establish individual urinary excretion of iodine (or any urinary 
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analyte) is to collect 24-hour samples (Bourdoux, 1998). However, without a reliable measure or 

indicator or iodine status, comparison s make suing this measure could be spurious. 

* Figure 1A illustrates the variability in urinary iodine concentrations in the Blount et al. dataset. 

[Figure 1A: Variability of Urinary Iodine from Blount et al. (2006) - See PDF Docket ID EPA-HQOW-2008-0692-1855] 

Response: See response to comment ID 29078 under comment code 2200. EPA does not have 

sufficient information to evaluate the WHO criteria for iodide status. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21083 

EPA Comment Code: 2200 

Comment: 1. Characteristics of individual members of the study group vary widely. Because many 

of these variables could impact overall subject health and, potentially, thyroid hormone or TSH 

levels, it is impossible to establish causality based on this dataset. The following is a sample of some 

of these variables-many others, both reported in and not reported in the dataset, could potentially 

impact thyroid measurements. 

* NHANES is a survey designed to assess the health and nutritional status of adults and children in 

the U.S. It is not a controlled epidemiological study. Up to 3,400+ different variables are reported in 

the online NHANES 2001-2002 dataset in association with specific study subjects. The potential for 

spurious associations between variables is significant. 

* 48% of those who responded were active smokers (42% reported smoking "everyday" and 6% 

"some days"; only 301 subjects out of 1,111 study subjects had a reported response to this question). 

21% of smokers reported smoking 15 or more cigarettes per day. Smoking status of study subjects 

under 18 years of age (29% of all study subjects) was not reported due to privacy concerns. In 

addition, 21% of study subjects reported living in a home with a smoker. Smoking is a known source 

of thiocyanate and other goitrogens. In smokers, cyanide from cigarette smoking is likely the most 

important source of SCN- in the body (Tonacchera et al., 2004). Ingbar (2000) states that 

thiocyanate as well as the pyridine components of cigarette smoke are likely a cause of lower T4 and 

T3 levels in serum of heavy smokers. Smoking and thiocyanate were found to be significant in a later 

analysis of the same data (Steinmaus et al., 2007). 

* 105 reported being pregnant at the time of the examination. Pregnancy is known to have an effect 

on thyroid economy with significant changes in iodine metabolism and serum thyroid binding 

proteins (Lazarus, 2005a; 2005b). 

* Although Blount et al. excluded subjects who were taking thyroid medications (e.g., levothyroxine) 

or certain other thyroid active agents (e.g., propylthiouracil or methimazole), subjects taking any 

other kind of drug were included. 43% of study subjects reported taking at least one prescription 

drug within the month preceding their examination interview. This includes subjects taking 
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medications known to directly affect the thyroid including lithium, amiodarone, and carbamazepine. 

Many drugs affect tests of thyroid function through alterations in the synthesis, transport, and 

metabolism of thyroid hormones, as well as via influences on thyrotrophin (TSH) synthesis and 

secretion. Despite effects on circulating thyroid hormone and TSH levels, few drugs result in 

important changes in clinical thyroid state, but difficulty in interpretation of thyroid function tests 

often results. Commonly prescribed drugs including anticonvulsants, non-steroidal antiinflammatory drugs, steroid hormones and heparin may result in abnormal thyroid function tests in 

the absence of clinical features of thyroid dysfunction. In contrast, lithium and iodine containing 

drugs, including radiographic contrast agents and amiodarone, may result rarely in overt thyroid 

disease (Davies and Franklyn 1991; Gittoes and Franklyn 1995; Wenzel 1996; Daminet and 

Ferguson 2003). 

* Many reported having one of a number of specific potentially severe medical conditions; however, 

only a limited list of conditions was reported. For example, 14 reported having had heart failure, 3 

had a current liver condition, 71 had current or past cancer, 13 had been told at some time they have 

weak or failing kidneys, and an unreported number (due to privacy concerns, presumably) had 

hepatitis C. Kidney failure is known to causes alterations in thyroid hormone metabolism known as 

nonthyroidal illness syndrome (Rosolowska-Huszcz et al., 2005). Hepatitis C patients on interferon 

therapy were found to be more susceptible to autoimmune thyroid diseases (Muratori et al., 2005). 

* 4% of adult study subjects are underweight (per CDC guidelines, BMI <18.5), 20% are obese 

(BMI >=30 and <40), and 4% are morbidly obese (BMI >= 40). Associations between body weight 

and thyroid hormone and TSH levels have been reported in obese and morbidly obese individuals 

(Sari et al., 2003; Michalaki et al., 2006). 

* Many report other types of exposures. 16% of study subjects reported using pesticides within their 

home during the previous month. A small number of women (16) reported using cocaine or other 

street drugs within the previous year, with one reporting using a drug on a total of 200 days during 

the previous year- because of the nature of this information, it could be assumed that this statistic is 

28 underreported. Illicit drug use status for subjects under age 18 was not reported. Associations 

between pesticide exposure and changes in thyroid hormone/TSH levels have been reported in 

some animal studies (Beard and Rawlings 1999; Jeong et al., 2006). T4 levels have been shown to 

decrease in rats following amphetamine administration (Budziszewska et al., 1996). 

* 66% of study subjects reported regularly (five or more times per month) consuming dark leafy 

green vegetables. Among these, consumption amount varied widely (up to 91 times per month). 

48% reported consuming cooked dried beans or peas five or more times per month. Dark green 

vegetables from the Brassica family (e.g., broccoli, kale) are known to contain high concentrations of 

both thiocyanate and nitrate, two agents known to cause iodide uptake inhibition (IUI) by the 

thyroid in the same way as perchlorate. Legumes are also known to contain high concentrations of 

nitrates. 

* 46% of study subjects reported taking dietary supplements during the month preceding their 

examination interview. 2% (22 subjects) admitted taking a dietary supplement during the fasting 

period. There is evidence that dietary supplements can affect thyroid function. For example, shortterm dietary supplementation with kelp (high in iodine) significantly increases both basal and 

poststimulation TSH (Clark et al., 2003). 
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* NHANES 2001-2002 does not report on consumption of soy or soy products. Soy consumption 

has been associated with development of goiter and an increase in TSH levels in humans (Doerge 

and Sheehan, 2002). Soy products are heavily marketed to women as healthful, including such 

products as soy milk, tofu, energy bars and drinks, and meat substitutes. Soy isoflavones (e.g., 

genistein and daidzein) can also be measured in biological samples such as serum, to give an 

approximation of soy intake levels. 

* Several other important study variables, including location and time of year when samples were 

collected, were not reported due to privacy concerns. Seasonally-related changes in thyroid hormone 

concentrations have been shown in adults, with higher T3 and T4 values seen in winter months, and 

a tendency to a greater TSH response to TSH-releasing hormone (TRH) was noted at this time 

(Harrop et al., 1985). These changes could reflect a centrally-mediated response of the 

hypothalamic-pituitary-thyroid axis to environmental temperature (Harrop et al. 1985). Significant 

annual, four-monthly and biannual rhythms were detected in serum TSH in adults, with the lowest 

detected in spring. A significant annual rhythm was detected in T3, with lower values in spring and 

summer than in the other seasons. The peak-trough differences in the yearly variation expressed as a 

percentage of the mean were 29.1% and 8.2% for TSH and T3, respectively (Maes et al., 1997). 

Response: No response is needed for information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21084 

EPA Comment Code: 2200 

Comment: 2. The "spot" urine and serum samples cannot be relied upon to establish chronic 

exposure levels or conditions. Spot samples are known to be inherently variable due to variations in 

urine volume and intake of exogenous compounds, and, in this population, fasting times varied 

widely between individuals and a substantial percentage of participants did not comply with study 

fasting requirements. 

* For chemicals with a short biological half-life (e.g., perchlorate, iodine), concentrations in spot 

urine samples are known to be highly variable between samples, due to within- and between-day 

variations in urine volume and intake of exogenous compounds (Barr et al., 2005). Factors shown to 

influence concentrations include fasting time, time of day, nature of the last meal, sample dilution, 

collection method, preservation method, sample interferences, and analytical method (Rasmussen et 

al., 1999). Urinary iodine concentrations in 24-hour samples vary up to three fold from one day to 

another. This suggests that a single sample is insufficient to determine long-term iodine status 

(Rasmussen et al., 1999). Population iodine excretion estimates require 100 to 500 spot urine 

samples for each group or subgroup and fewer than 10 urine samples in an individual may be 

misleading (Anderson et al., 2008). 

* Serum and urine samples were collected at either "morning" (46%), "afternoon" (36%), or 

"evening" (18%) examination sessions. Specific sample time of day is not given. In humans, serum 

TSH concentrations are at their maximum at night, shortly before sleep, about 50-100% greater than 

the morning low (Fisher, 1996). Early morning values are greater than later morning values (Surks et 

al., 2005). TSH is secreted in pulses, with eight to fourteen pulses occurring in 24 hours. Sleep 
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deprivation, strenuous exercise, or working during night or evening shifts accentuate the rhythms 

(Surks et al., 2005). 

* Fasting times were highly variable. Subjects appointed to a morning session were asked to fast for 

9 hours while subjects appointed to an afternoon or evening session or a home exam session were 

asked to fast for 6 hours. However, the protocol states the "greater goal [is] completing as many 

components as possible within the time constraints of the session with phlebotomy as the highest 

priority component." Reported length of fast ranged from 0 to 63 hours, with a mean and 50th 

percentile of 10.3 hours and 5th and 95th percentiles of 1.7 hours and 19 hours, respectively. For the 

morning, afternoon, and evening sessions, 8%, 13% and 24%, respectively, did not meet the fasting 

requirement. 

* About 2% (22/1111) admitted taking a dietary supplement during the pre-blood and urine 

collection fasting period. There is evidence that dietary supplements can affect thyroid function. For 

example, short-term dietary supplementation with kelp (high in iodine) significantly increases both 

basal and poststimulation TSH (Clark et al., 2003). 

* Study participants were allowed to consume diet soda, black coffee or tea with saccharine or Equal 

since "these have no affect on study analytes." (Protocol p. 4-32). It is relatively clear that sugar 

substitutes such as those used in diet sodas do not have a significant impact on thyroid function. 

However, the evidence for a lack of effect with caffeine is less clear. Studies in rats have shown that 

injection of caffeine results in a decrease in serum TSH followed by a subsequent decrease in serum 

T3 and T4 (Spindel et al., 1980). However, no effect on thyroid parameters were found in men (TSH 

and T3) or Syrian hamsters (TSH, T4, and T3) (Spindel et al., 1984; Bartsch et al., 1996). 

* Figure 2A illustrates the variability in the fasting times. Though no direct correlation between 

urinary iodine (and perchlorate) measures and fasting times is seen, it is unclear whether fasting time, 

exclusive of all of the other variables 30 inherent in this dataset, could have affected urinary 

concentrations in a well-controlled dataset. 

[Figure 2A: Variability of Fasting Times from NHANES 2001-2002 - See PDF Docket ID EPAHQ-OW-2008-0692-1855] 

Response: No response is needed for the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21085 

EPA Comment Code: 2200 

Comment: 3. The observed differences in perchlorate are that thyroid response between men and 

women are not explained, which could be due to another unexplained variable. Comparable 

differences have not been observed in previous studies of perchlorate exposure (e.g., Greer et al., 

2002; Braverman et al., 2006; Crump et al., 2000). Missing database variables make it difficult to 

exclude other possible causes of the observed differences between men and women. 
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* Thyroid autoantibodies are not measured in NHANES 2001-2002. Women are known to be about 

2.7 times more likely to acquire an autoimmune disease than men (Jacobson et al., 1997), and to 

have a greater incidence of thyroid autoimmunity (Chiovato et al., 1993). Thyroid autoantibody 

levels have been shown to be positively correlated with TSH levels in humans (Hollowell et al., 

2002; O'Leary et al., 2006; Hoogendoorn et al.,2006). In analysis of data from NHANES III, a 

significant association between female gender and elevated serum TSH levels disappeared when 

controlled for TPOAb (Hollowell et al., 2002). 

* The NHANES dataset does not include a variable directly characterizing time since last pregnancy; 

this value can be approximated based on reported "age at last live birth" and current age. Using this, 

about 7.5% of women not currently pregnant reported being pregnant within the previous 2 years. 

The possibility that postpartum thyroiditis afflicted some of these women cannot be excluded. 

Postpartum thyroiditis, a syndrome of transient or permanent thyroid dysfunction caused by 

autoimmune inflammation of the thyroid, occurs frequently in the first year after delivery, with a 

prevalence of about 5-7% (Muller et al., 2001). In about 25-30% of these women, the condition 

progresses to permanent hypothyroidism (Lazarus, 2005b). 

* Figures 3A and 4A depict the variability in the NHANES data set and the nominal changes noted 

in thyroid hormones. 

[Figure 3A: Variability of Perchlorate in NHANES Data Set - See PDF Docket ID EPA-HQ-OW2008-0692-1855] 

[Figure 4A: Variability of Perchlorate and Changes in Thyroid Horomones - See PDF Docket ID 

EPA-HQ-OW-2008-0692-1855] 

Response: No response is needed for the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21086 

EPA Comment Code: 2200 

Comment: 4. Spot urine concentrations of nitrate and thiocyanate, two other inhibitors of iodide 

uptake into the thyroid, were highly variable among study subjects. Since perchlorate, nitrate, and 

thiocyanate all act through the same mechanism of action (iodide uptake inhibition (IUI) at the 

thyroid), evaluation of correlations between exposure to iodide uptake inhibitors and thyroid 

hormone or TSH concentrations should take into account combined exposures to all three anions. 

* Perchlorate equivalent concentrations of nitrate, thiocyanate, and perchlorate in urine in the study 

population (calculated assuming that nitrate is 1/240 as potent and thiocyanate is 1/15 as potent as 

perchlorate; Tonacchera et al., 2004) ranged from 3.7 to 3329 ug/L. On average, for any given 

subject, perchlorate comprised about 1% of the total perchlorate equivalent concentration 

(geometric means are 2.8 and 270 ug/L for perchlorate and perchlorate equivalent concentration, 

respectively). One would expect to see thyroid effects of nitrate or thiocyanate before seeing 

perchlorate effects; however, Blount et al. (2006) report no reliable associations between urine levels 

of nitrate and thiocyanate and serum total T4 or TSH. 
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* No correlation between perchlorate equivalent concentration and serum total T4 or serum TSH is 

apparent. Perchlorate equivalent concentration was not a significant predictor of total T4 (p=0.43, 

coefficient -0.00011) or TSH (p=0.25, coefficient -0.00023). Conceivably, the same problems 

inherent in relying upon spot urine samples as indicators of longer term iodine intake would affect 

the reliability of spot urine samples for perchlorate, nitrate, and thiocyanate. 

Response: No response required for the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21087 

EPA Comment Code: 2200 

Comment: Missing Data 

Some of the key data related to this study were not accessible in the time frame of this project. For 

instance, the analytical quality assurance/quality control data is available for review through the 

National Center for Health Statistics (NCHS), but NCHS requires reviewers to request an 

appointment and travel to their location to review the data. Other data would need to be obtained 

under the Freedom of Information Act (FOIA). Key data that could be obtained through these 

mechanisms might include exact times of blood samples and urine samples, the sequence of sample 

collection, QA/QC of the analyses, analytical logbooks, and other notes from the survey. These are 

critical pieces of information that could be useful to characterize the dataset and examine the 

significance of associations. 

Response: No response is needed for the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21088 

EPA Comment Code: 2200 

Comment: Summary 

If one considered this as a pilot study which would be consistent with the stated intended use, then 

the appropriate and logical next step would be to address a number of these concerns with an 

enhanced experimental design. For example, adding critical thyroid function variables (e.g., free T4, 

anti-TPO), 24-hour urine collections, and better control of medications will provide a more 

appropriate study design. 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Steve Lamm 

Commenter Organization: Consultants in Epidemiology and Occupational Health, LLC (CEOH) 

EPA Document ID: EPA-HQ-OW-2009-0297-0654 
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EPA Comment ID: 28486 

EPA Comment Code: 2200 

Comment: Attached are our comments on perchlorate (10-08-09). The cited references will be 

submitted separately. 

October 8, 2009 

Eric Burneson Office of Ground Water and Drinking Water Standards and Risk Management 

Division Environmental Protection Agency 

Re: Docket ID No. EPA-HQ-OW-2009-0297 

Comments on Scientific Literature on Public Health levels of concern of perchlorate in drinking 

water 

EPA is considering whether to specifically regulate the level of perchlorate in drinking water and 

needs to consider the potential adverse effect on human health, the frequency and level of exposure, 

and whether regulation of the contaminant represents a meaningful opportunity for reducing public 

health risks. EPA states that it is particularly concerned about the fetus of the iodine-deficient 

pregnant mother, infants, and developing children." 

I review below the literature on the question as to whether the Blount et al. (2006) analysis 

demonstrates a risk from background perchlorate exposures on "the fetus of the iodine-deficient 

pregnant mother, infants, and developing children?" I conclude that it does not. 

Lamm et al. (2007, under review) demonstrate that the primary Blount finding on perchlorate effect 

on thyroxine level at low iodine level is dependent on the definition of low iodine as low urinary 

iodine (<100UG/l) on a single sample. It is not found when creatinine-adjusted urinary iodine level 

is used as the metric for defining low iodine. Thus, the primary finding is dependent on analytic 

method and not robust to reasonable variants of definition. 

Pearce et al.(2007, 2008 under review) demonstrate that maternal thyroid function is not adversely 

affected by background levels of perchlorate among first trimester pregnant women from mild or 

moderate iodine deficient populations or with low urine iodine levels (< 100 ug/L). 

Review of published literature is consistent with findings of studies pending publication. Replication 

of the Blount et al. (2006) type analysis will be possible with the NHANES 2007-2008 dataset. 

Regulatory assessment should not be considered independent of these findings. My presentations 

below provide the bases for the above statements. 

Two major issues that I do not deal with here but that must be recognized is (1) that the biological 

effect proposed by the Blount et al. (2006) analysis is at an exposure level one to two orders of 

magnitude below that at which effects of perchlorate exposure have been observed and (2) that the 

issue of iodine adequacy for pregnant women and their offspring in the United states is important, 

complex, and appropriate for discussion elsewhere. 
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Is there a negative association between perchlorate and thyroxine with low iodine status? 

Blount et al. (2006) is the only report that suggests that there is a biological effect from perchlorate 

at general US population exposure levels. They have analyzed data from NHANES 2001-2002 and 

report that women with low urine iodine levels have reduced total thyroxine (tT4) levels associated 

with increasing levels of urinary perchlorate, i.e., a negative association between urine perchlorate 

level and serum total thyroxine level among women with urinary iodine level < 100 ug/L. Steinmaus 

et al. (2007) further indicates that this finding is confounded by smoking. 

The Blount et al. (2006) analysis has been interpreted as indicating that the children of women with 

low iodine status may be at increased risk of neurodevelopment deficit associated with their 

perchlorate exposure. This is an over-interpretation. 

(1) There is no accepted measure for iodine status of an individual within a population. The 

reference point of 100 ug/L (or 100 ug/g creatinine) refers a population, not an individual. A low 

urine iodine level in a single urine sample does not equate to a finding of low iodine status. 

The usual measure of iodine status is 24-h urinary iodine excretion, and the NHANES datasets do 

not give that metric. Historically, the 24-h urinary iodine excretion for an individual has been 

estimated from the urine iodine to urine creatinine ratio (e.g., Rasmussen 1999). This metric could 

be calculated from the NHANES dataset but is not included in the Blount et al. (2006) analysis. 

Even that would be a point estimate and not represent the general iodine status of the individual but 

only the iodine throughput status of that day. Andersen et al. (2001) have shown that single low 

measurements of iodine level on one day do not demonstrate as an average a low iodine level over 

multiple specimens over a long period of time (one year). 

Laurberg et al. (2007) should get particular attention as it deals with many of the issues confronting 

EPA on perchlorate and has been developed independent of any perchlorate issues. They succinctly 

summarize the Andersen et al. (2001) paper as demonstrating that "in a group of people, the 

distribution of average iodine concentrations in several samples from the same subjects is much 

narrower than the distribution of values from single spot samples from the same people." They 

observe that "Only the median or average can be used to classify iodine intake." They conclude that 

"the concentration of iodine in a spot or casual urine sample cannot be used to diagnose iodine 

deficiency in an individual." 

(2) The Blount et al. (2006) analysis has not analyzed separately these relationships for women of 

child-bearing age (WCBA, ages 15-44), which would be the relevant population with respect to 

protecting fetal health. 

An analysis of the NHANES 2001-2002 data set for women of child-bearing age using 

iodine/creatinine as the metric of iodine exposure has examine the relationship of total thyroxine 

(tT4) with regarding to an association with urinary levels of perchlorate (and the other two iodineuptake inhibitors, thiocyanate and nitrate) for those with low, medium, and high iodine/creatinine 

(Lamm et al., 2007). Lamm et al. (2007) has been published in abstract form and is currently under 

review for peerreview publication. 

Lamm et al. (2007) demonstrated that "the negative association of serum thyroxine and urinary 

perchlorate found for WCBA with low iodine defined by UI (ug I/L urine) was not found for those 
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with low iodine defined by UICr (ug I/g creatinine)." Their analyses, in contrast, found such an 

association for WCBA with high iodine/creatinine. 

This is not the place to discuss which of these two analyses are "right", but rather to observe that the 

Blount finding was highly dependent upon the specific metric used to classify low iodine. The lack 

of robustness with respect to the definition of low iodine suggests that the analytic results are 

method dependent, rather than a reflection of underlying biology. In this case, it is premature to 

serve as a basis for regulatory decision-making. 

It should be noted that the Lamm et al. (2007 and 2010 pending) analysis of the NHANES 2001-

2002 data set demonstrated that a negative association between serum thyroxine level and urinary 

thiocyanate level was found in WCBA with high iodine level rather than low iodine level, a finding 

consistent with a similar analysis of the NHANES III dataset (Vanderver et al., 2007). The 

replication of this finding in a second NHANES dataset is noteworthy. The Vanderver et al (2007) 

study further uses as its endpoint metric not the serum thyroxine level but the prevalence of 

hypothyroxinemia, which may be a better metric of outcome. 

While the NHANES III dataset did not contain measurements of perchlorate, the NHANES 2007-

2008 dataset that is currently being released does. The NHANES 2007-2008 dataset will be 

appropriate for examining these analytic issues. Analyses of the NHANES 2001-2002 dataset does 

not resolve them. 

Response: See response to comment ID 29078 under comment code 2200. 

Commenter Name: Jonathan Borak 

Commenter Organization: Yale School of Medicine 

EPA Document ID: EPA-HQ-OW-2009-0297-0209 

EPA Comment ID: 28507 

EPA Comment Code: 2200 

Comment: 2). A related, but different issue involves the use of spot urine testing to diagnose 

individuals as "low iodine intake" or "iodine deficient". I raise this concern for three reasons: 

1). The Blount et al. and Steinmaus et al. analyses found significant effects principally in women with 

spot urine iodine levels <100 ug/L, not in those with spot iodine levels >=100 pg/L. However that 

100 ug/L cut-off level is derived from a WHO/UNICEF/ICIDD criterion for determining iodine 

sufficiency in populations, not individuals. 

2). There is a general consensus that "impacts of perchlorate exposure will vary depending upon an 

individual's iodine sufficiency" (15). Thus, predicting the adverse effects of perchlorate exposure 

requires knowledge of individuals' iodine sufficiency. 

Response: See reponse to comment IDs 29078 and 28531 under comment code 2200. 

Commenter Name: Andria Ventura 

Commenter Organization: Clean Water Action et al. 

EPA Document ID: EPA-HQ-OW-2009-0297-0528 
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EPA Comment ID: 28515 

EPA Comment Code: 2200 

Comment: Moreover, a 1 ppb or lower MCL is supported by the most recent comprehensive 

studies, and these should be central to EPA's analysis. The industry-supported Greer study, which 

serves as the basis for EPA's current reference dose as well as California's current 6 ppb standard, 

consisted of a 14-day study of 37 healthy adults. In more recent years, Blount et al analyzed a 

nationally representative sample of 2299 U.S. residents, and they have documented anti- thyroid 

effects in a large population of women exposed to perchlorate at concentrations far lower than 

levels previously shown to have such effects. This study and subsequent data clearly justify 

promulgation of an even more protective MCL. It should be noted that California's Office of 

Environmental Health Hazard Assessment is in the process of reevaluating its Public Health Goal, 

on which the state MCL is based. 

Response: EPA intends to determine the value for the MCLG in developing a proposed NPDWR 

with consideration of the best available, peer reviewed science. A value for the MCLG has not yet 

been determined. 

Commenter Name: Richard T. Kloos 

Commenter Organization: American Thyroid Association (ATA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0635 

EPA Comment ID: 28531 

EPA Comment Code: 2200 

Comment: Of great concern to us is the fact that women with low iodine status appear to be at 

particular risk of perchlorate effects. The study of Blount et al. demonstrated that among the 36% of 

women with urinary iodine values <100 ug/L in the NHANES 2001-2002 data set, there was a 

significant positive correlation between urinary perchlorate concentrations and serum TSH 

(p=0.001) and an inverse correlation between urinary perchlorate concentrations and serum T4 

values (p<0.0001).12 Among women with urinary iodine values >100 μg/L, there was a positive 

association between urinary perchlorate concentrations and serum TSH (p=0.025), but there was no 

association between urinary perchlorate concentrations and serum T4 values. There were no 

significant associations between urinary perchlorate concentrations and thyroid function values in 

men irrespective of iodine intake. Therefore, if the results of this study are correct, the population at 

highest risk for adverse effects of environmental perchlorate exposure is women with low dietary 

iodine intake. 

Response: EPA agrees that promoting iodide nutrition is good public health policy and may have a 

positive influence in reducing the iodide uptake inhibition effects associated with exposure to 

perchlorate. However, the Agency does not think it is appropriate to rely on the promotion of 

iodide nutrition in this case, especially since these activities are outside of EPA’s SDWA authority. 

While the health concerns associated with perchlorate may be addressed through other means, it is 

the Administrator’s judgment that a standard limiting perchlorate in drinking water can reduce 

health risk, particularly to fetuses, infants and children. 

Commenter Name: John P Gibbs 
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Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0636 

EPA Comment ID: 28553 

EPA Comment Code: 2200 

Comment: 4) THE USE OF THE NHANES DATA AS A POINT OF DEPARTURE 

The NHANES 2001-2002 epidemiological urinary data are from a single un-timed spot urinalysis 

and can vary due to dilution or concentration of the urine (i.e., due to an individual’s hydration 

status). A common technique to eliminate this variation in the spot urinalysis is to normalize the 

iodide urine concentration against creatinine resulting in the analysis expressing iodide excretion as 

ug of iodide/g of creatinine (i.e., ug/g creatinine) instead of ug of iodide/L of urine. Lamm has 

successfully repeated Blount’s statistical analysis of the NHANES 2001-2002 epidemiological data 

only when his analysis measures UIC as ug/L (Lamm 2007). However, when Lamm 2007 repeats 

the statistical analysis using only women of childbearing age (ages 15-44 years) and UIC measured as 

ug/g creatinine, the statistical significance of the relationship between decreasing tT4 with increasing 

perchlorate exposure in women with low UIC is lost. The statistical significance of this relationship 

should be present regardless if the analysis expresses UIC in ug/L or ug/g of creatinine. This 

inconsistency suggests that the relationship between tT4 and perchlorate reported in the Blount 

analysis might be an artifact in the NHANES data set. The figures below show significant scatter in 

the perchlorate vs T4 and TSH correlations from the NHANES datset and cast considerable doubt 

on the clinical significance of any statistical significant findings reported by Blount et al 2006. 

[Figure. Gender groups - Perchlorate vs T4 - see PDF docket ID EPA-HQ- OW-2009-0297-0636] 

Additionally, studies among pregnant women do not demonstrate a correlation between urine 

perchlorate and thyroid function, A cohort of 789 pregnant women (i.e., 396 from Cardiff, Wales; 

311 from Turin, Italy; and 82 from Dublin, Ireland) with perchlorate exposure levels shows no 

association between urinary perchlorate levels and free T4 levels in the pregnant women as a group 

or in the subgroup of pregnant women with UIC <= 100 ug/L (Pearce 2007). . A cohort of 230 

pregnant women (i.e., 128 from Los Angeles, California; 102 from Cordoba, Argentina) with low 

perchlorate exposure levels predicted by the Blount analysis to induce a reduction of tT4 shows no 

association between urinary perchlorate levels and free T4 levels in the pregnant women as a group 

or in the subgroup of pregnant women with UIC <= 100 ug/L (Pearce 2008). From the 2005 Tellez 

cohort study (Tellez 2005) in three Chilean cities, a reanalysis of the data identified 16 of the 

pregnant women had UIC <= 100 ug/L (Gibbs 2008). The reanalysis shows no association between 

urinary perchlorate levels and free T4 levels in this subset of pregnant women with UIC <= 100 

ug/L. 

Response: See response to comment ID 29078 under comment code 2200. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0653 

EPA Comment ID: 28561 

EPA Comment Code: 2200 
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Comment: The Blount et. al. studies were useful in demonstrating that although perchlorate 

exposure is widespread (through diet), the review of the NHANES data clearly indicated that 

thyroid hormone levels measured in the study were clinically normal, even in the presence of 

perchlorate and other goitrogens such as nitrate and thiocyanate. The Blount et. al. 2006 study did 

show, however, that iodine nutrition is a significant concern, especially for women of childbearing 

age. The conclusions concerning associations purported in Blount et. al. 2006 are problematic as the 

authors failed to use consistent models to derive their findings across age, sex, ethnic and other key 

variables. Furthermore, it is hard to lend credence to associations between thyroid hormones and 

perchlorate exposure that are negative in one case for women with low urinary iodine excretion 

while being positive for other women. As a continuous variable, one might expect to see a more or 

less negative value between the groups, but not a complete change in the direction of the slope for a 

well-defined biological process. The statistical significance reported by the authors may be a result of 

the iodine level instead of the perchlorate level, as low iodine would result in elevated TSH and 

reduced T4 levels, while higher (i.e. sufficient) iodine levels would not be expected to result in a 

statistical association between thyroid hormone levels and iodine or perchlorate, as demonstrated in 

the study. 

Response: See response to comment ID 29078 under comment code 2200. 

Commenter Name: Kathy Dolan 

Commenter Organization: Food and Water Watch (FWW) 

EPA Document ID: EPA-HQ-OW-2009-0297-0526 

EPA Comment ID: 28608 

EPA Comment Code: 2200 

Comment: Perchlorate has been found in the drinking water supply of 35 states and the District of 

Columbia. Widespread human exposure to perchlorate was confirmed by the Center for Disease 

Control's NHANES study, which found that 100 percent of the 2,820 randomly selected study 

participants had detectable levels of perchlorate in their urine. And according to your request for 

comment notice, dated August 5, 2009, the number of people served by water contaminated with 

high levels of perchlorate ranges between 53.4 and 16.8 million people. 

Response: Under the first Unregulated Contaminant Monitoring Rule (UCMR 1). EPA collected 

and analyzed drinking water occurrence data for perchlorate from 3,865 PWSs between 2001 and 

2005 under the UCMR 1. The minimum reporting level (MRL) for perchlorate under the UCMR 1 

was 4 μg/L. EPA found that 160 (approximately 4.1 percent) of the 3,865 PWSs that sampled and 

reported had at least 1 analytical detection of perchlorate (in at least 1 sampling point) at levels 

greater than or equal to the MRL of 4 μg/L. These 160 PWSs are located in 26 States and 2 

territories. Of these 160 PWSs, 8 are systems serving 10,000 or fewer people and 152 are systems 

serving more than 10,000 people. These 160 systems reported 637 detections of perchlorate at levels 

greater than or equal to 4 μg/L, which is approximately 11.3 percent of the 5,629 samples collected 

by these 160 PWSs and approximately 1.9 percent of the 34,331 samples collected by all 3,865 

PWSs. The average concentration of perchlorate for those samples with positive detections for 

perchlorate was 9.85 μg/L and the median concentration was 6.40 μg/L. 

Table 1 in the final regulatory determination presents the number and percentage of PWSs that 

reported perchlorate at levels exceeding various threshold concentrations. 
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Table 2 of today’s notice presents EPA’s estimates of the population served by PWSs that were 

monitored under UCMR 1 for which the highest reported perchlorate concentration was greater 

than the thresholds identified in Table 1. These population estimates are for people at all life stages. 

EPA has determined that a NPDWR for perchlorate could reduce perchlorate exposures for these 

populations to levels below the potential alternative HRLs that EPA has identified as levels of public 

health concerns for purposes of this determination, and that such exposure reductions present a 

meaningful opportunity for the reduction of health risks for persons served by PWSs. 

Commenter Name: Sonia Salas 

Commenter Organization: Western Growers Association on behalf of several California 

agriculture groups 

EPA Document ID: EPA-HQ-OW-2009-0297-0652 

EPA Comment ID: 28682 

EPA Comment Code: 2200 

Comment: U.S. EPA uses the US Centers for Disease Control and Prevention's National Health 

and Nutrition Examination Survey (NHANES) biomonitoring dataset in concert with the FDA 

TDS dataset to estimate the relative proportional intake of perchlorate from both food and water 

sources. The NHANES data provide the best available measure of actual human exposure to 

perchlorate from all sources, including food and water, using urinary perchlorate concentrations 

from a large U.S. population cohort. The overall exposure to perchlorate from all sources based on 

the NHANES data is below any meaningful level of concern identified in the available scientific 

literature. Thus, as a fraction of total exposure, intake of perchlorate from food alone must be well 

below any meaningful level of concern. FDA's TDS and food sampling data, which provides an 

approximation of human exposure to perchlorate from food, validates this conclusion. 

Recent Epidemiological Data, Including the Blount (2006) Analysis of NHANES Data, Should Not 

Be Used as a Basis for a New Perchlorate Regulatory Determination. 

The undersigned groups support EPA's decision to base its perchlorate regulatory determination on 

the NAS RfD. Some have argued that the Blount (2006b) results, which show a slight correlation 

between perchlorate in urine and changes in thyroid hormone levels in women with sub-optimal 

iodine levels, should be given considerable weight in EPA's review of its preliminary regulatory 

determination. In fact, the Blount analysis has several limitations which necessarily impede its use in 

drawing conclusions regarding the health effects of perchlorate, particularly for purposes of risk 

assessment and regulatory decision making. Chief among these is the fact that Blount (2006b) does 

not establish direct causation, only an association between two independent data sets. A number of 

intervening factors could cause or contribute to the reported decrease in thyroid hormone levels, 

including methodological issues such as the use of relevant measures of thyroid function (total T4 

versus free T4) and appropriate biomonitoring data (24 hour urine versus spot urine samples). 

Second, even if changes in thyroid hormone levels were considered adverse (they are not), the 

changes identified in Blount (2006b) were not outside the normal ranges for thyroid hormone levels. 

Third, estimated perchlorate doses based on the urinary concentrations were below the level that can 

trigger inhibition of iodide uptake, the non-adverse precursor effect that is the basis of the NAS 

NOEL. 
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The Blount (2006b) results conflict with the overwhelming body of scientific evidence showing that 

perchlorate has no effect on the thyroid at environmentally relevant levels. Similar concerns have 

been raised by independent organizations such as the American Thyroid Association[FN2: The 

American Thyroid Association in 2007 concluded that the CDC study findings were "intriguing," 

but limited in their application to the setting of exposure standards. 

(http://www.thyroid.org/professionals/publications/statements/06_12_13_ perchlorate.html).], 

and a key member of the NAS perchlorate panel has indicated that the NAS RfD remains 

sufficiently health protective[FN3: In April 2007 - after publication of the CDC study - NAS 

panelist Dr. Robert Utiger, senior physician with the Harvard Institutes of Medicine, testified before 

Congress and stated: "I continue to believe that a reference dose of 0.007 mg/kg/day (24.5 ppb) is 

quite adequate."]. 

Response: EPA disagrees that the overwhelming body of scientific evidence shows that perchlorate 

has no effect on the thyroid at environmentally relevant levels. See response to comment ID 29078 

under comment code 2200. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0647 

EPA Comment ID: 28717 

EPA Comment Code: 2200 

Comment: If the association between perchlorate and thyroid hormone levels was causal, as is 

sometimes inferred from the Blount study, then logically the effects of thiocyanate and nitrate 

observed by Blount in connection with those same hormones should also be viewed as causal. If 

that were so, it would then appear that thiocyanate has all of a sudden become a remedy against 

goitrogens instead of a goitrogen itself, and nitrate would only act as a goitrogen when iodine levels 

were sufficient. That of course would be very surprising, and would be inconsistent with years of 

scientific observations and studies regarding these substances. As discussed in greater detail below, 

we have reviewed the information presented in the Blount study regarding perchlorate, and the full 

range of substances in the same NHANES 2001-2002 database, and have concluded that 

perchlorate is not the cause of observed TH impacts, but is simply a marker for other thyroid 

affecting substances. 

1. The four orders of magnitude difference between the adverse effect levels found in the two most 

cited recent studies in relation to perchlorate, the Greer study and the Blount study 

In stark contrast to all previous studies, the results of the Blount study suggest that if the 

relationship between perchlorate and thyroid hormones is causal, perchlorate is about 10,000 times 

more potent than previously found. It is simply not plausible that all other studies would have 

missed this surprising outcome, particularly in view of the fact that perchlorate was and still is used 

as a drug in the treatment of thyroid disorders. 

From Blount (NHANES 2001-2002) data and regression curves, the average urinary level of 2.84 

ug/L, which is found to be related to thyroid hormone (TH) change, is equivalent to an oral 

perchlorate dose of approximately 0.00004mg/kg- day[FN2: Blount BC, Valentin-Blasini L, 

Osterloh JD, Mauldin JP, Pirkle JL, 2006a. Perchlorate Exposure of the U.S. Population, 2001-2002. 
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Journal of Exposure Science and Environmental Epidemiology, 1-8.]. This is 100 times lower than 

the dose of 0.004 mg/kg-day that was found in the Greer study to be without effect not even on 

iodide uptake and which led to the NAS RfD based on a (slightly higher) NOEL of 0.007 mg/kgday. Further this dose of 0.004 mg/kg-day on itself is about 100 times smaller than 0.5mg/kg-day, 

the dose found to have no effect on THs[FN3: NAS 2005, Health Implications of Perchlorate 

Ingestion, The National Academies Press, Washington, DC, 2005.]. So, in stark contrast to what has 

been found in the body of the literature, the conclusions of the Blount study would suggest that 

perchlorate is about 10,000 times more potent than measured in previous studies as illustrated in fig. 

3, below. 

Fig. 3 [see PDF docket ID EPA-HQ-OW-2009-0297-0647] 

The NAS RfD of 0.0007 mg/l has often been expressed in the media as "a couple of drops in an 

Olympic seized swimming pool" to make it more visually comprehensible. We could push this 

metaphor a bit further: the 10,000 times lower dose would then mean that the level represents a 

couple drops in 10,000 Olympic sized swimming pools. If the effect of perchlorate were indeed so 

strong, the resulting drinking water public health goal (PHG) would be well below 25/100 ppb and 

closer to 25/10,000 ppb or 0.0025 ppb which is at least 2 orders of magnitude below the mean 

natural perchlorate background in drinking water. 

Finally, if the causal interpretation of the results of the Blount study are to be believed, the 

downstream TH adverse effect level of 0.00004 mg/kg-day would be 2 orders of magnitude lower 

than the upstream iodine uptake inhibition non- effect level. This is in itself contradictory, since 

according to NAS "a perchlorate dose that does not inhibit thyroid iodide uptake will not affect 

thyroid function" (ref. 2 above) and thus cannot affect TH levels. 

A sudden four order of magnitude difference in effect level attributed to a well studied substance is 

extremely improbable. It is instead far more likely that the study’s interpretations regarding the 

impact of low doses of perchlorate are inaccurate and should not be relied upon as a basis for 

regulation. 

2. The cause of the TH changes in the Blount et al. study: is it another substance or an 

environmental pool of substances? 

Response: See response to comment ID 29078 under comment code 2200. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28897 

EPA Comment Code: 2200 

Comment: B. Recent Studies Listed in the 2009 FR Notice 

The Notice states that EPA has evaluated additional data made available since the 2005 RfD 

determination. In response to comments suggesting that other studies, particularly Blount et al. 

(2006), be used for defining a regulatory standard, EPA noted that new studies have provided 

important information to the scientific literature, but that it has "decided to make the regulatory 
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determination based upon the current RfD." The papers EPA listed are summarized below. Based 

on these data, Greer et al. (2002) continues to provide the best scientific information to be used as 

the basis for EPA's perchlorate RfD risk assessment. 

Most of these comments have been presented by Intertox in the past. Where appropriate, however, 

these summaries are updated with new information. 

Blount et al. (2006) 

Using the NHANES 2001-2002 data set and a cross-sectional study design, Blount et al. (2006) 

report measurement of urinary perchlorate, urinary iodide, serum TSH, and serum total T4 levels in 

men and women over the age of 12. The 2001-2002 NHANES data provide the largest group of 

subjects to date from which sampling data can be derived. The authors report that perchlorate levels 

were not associated with total T4 or TSH levels in men, but were a negative predictor of total T4 

and a positive predictor of TSH in women with urinary iodine less than 100 ug/L. They report that 

in women with urinary iodine greater than 100 ug/L, urinary perchlorate was a positive predictor of 

TSH, but not associated with T4. The significance of evaluating women with urinary iodide less than 

100 ug/L is based on the World Health Organization (WHO) statement that a median urinary iodine 

concentration for the entire population, based on spot samples of less than 100 ug/L, is indicative of 

overall iodine deficiency for that population (WHO, 2004). 

This study has drawn a great deal of attention as it may be misinterpreted to demonstrate an "effect" 

of perchlorate, albeit at exposures below those that cause measurable IUI. A number of 

considerations, however, should be noted to better understand the significance of the data reported. 

First, as stated above, ATSDR (2008) reviewed this study in their assessment and did not feel it 

merited any special consideration over other studies in the well developed perchlorate literature 

database. It states that its decision "...was made after a careful evaluation of the NRC report and of 

studies that have been published after the NRC (2005) report. The results from newer studies do not 

change the bottom-line recommendation" (ATSDR, 2008). 

Second, it is important to interpret the results of scientific research based on what is known about 

the biological system. For example, there is a difference between "statistical significance and "clinical 

significance." A "statistically significant" difference simply means it is unlikely that a difference 

between two variables (e.g., measurements) is due to chance. With a well designed experiment, 

statistical significance can be extremely important. Because statistical significance is also a function 

of sample size, variability in the variables measured, etc., the finding of statistical significance does 

not necessarily mean the difference is large, important, or biologically significant. For biological data, 

it is important to understand whether something that is statistically significant is also clinically 

significant; that is, whether a change in a variable or parameter is large enough to affect a clinical or 

medical condition (e.g., development of hypothyroidism). Blount et al. (2006) report statistically 

significant relationships for some variables, but do not report any variables with clinical significance, 

such as free T4. 

The type of study conducted by Blount and colleagues (i.e., a cross-sectional study) cannot 

determine causation, only association between the variables studied (Wartenberg and Buckler, 2001). 

If important variables are missing, then spurious conclusions can be made. Thus, without a full set 
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of thyroid-specific variables measured, including repeated 24-hour urinary iodide measurement, any 

association should be examined carefully for reliability. 

Furthermore, perchlorate did not actually lower (nor was it associated with) thyroid hormone levels 

outside the normal range of values. Assuming that it had, the NRC committee does not think that 

"...transient changes in serum thyroid hormones or TSH concentrations are adverse health effects; 

they are simply biochemical changes that might precede adverse effects" (NRC, 2005). For each 

individual in the NHANES study, a single spot urine sample and a single plasma sample for analysis 

of thyroid hormones and other parameters were collected. These data do not provide more than a 

"snapshot" or transient assessment of these individuals. 

Regarding Blount et al. (2006), ATSDR states, "limitations of the study acknowledged by the 

investigators include those common to cross-sectional analyses, the assumption that urinary 

perchlorate correlate with levels in the thyroid stroma and tissue, and the measurement of total T4 

rather than free T4" (ATSDR, 2008). 

Third, any study must have careful consideration for the parameters and variables that are measured 

or available and how these variables relate to the outcome of interest. NHANES is designed to 

collect a broad range of data about the health and diet of people in the United States. NHANES 

collected data on some parameters relevant to thyroid function, but these parameters fall short of 

providing sufficient information needed to clearly understand thyroid health. Only two clinical 

measures of thyroid function were taken (total serum T4 and TSH). Missing where free T4, thyroid 

binding globulin (TBG), and T3 among others. Iodine status was reported on the basis of spot urine 

samples, which are neither the preferred, nor most reliable, measure of urinary iodide (Barr et al., 

2005). Further, NHANES did not collect data on the incidence of autoimmune thyroiditis, the most 

common thyroid disorder in the U.S., which causes changes in serum T4, T3, and TSH 

concentrations due to errant immune mechanisms attacking the thyroid gland, called Hashimoto's 

thyroiditis (NRC, 2005). Intertox (2008) provides a more thorough discussion regarding the use of 

spot urine testing, confounders, and use of the available NHANES variables to draw conclusions. 

This study did not present urinary measures normalized to creatinine, although creatinine was 

included as a variable in the regression analysis. The concentration of dissolved substances in urine, 

such as iodide, may vary between individuals or between samples from the same individual based on 

water intake. Normalization with creatinine is meant to normalize for dilution, not variability due to 

differences in exposure. It is not a perfect method, but is commonly used to account for this 

dilution (Furnee et al., 1994). Normalization may have been particularly useful in dividing the 

women up in to those with urinary iodide less than and greater than 100 ug/L. 

Response: See response to comment ID 29078 under comment code 2200. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28899 

EPA Comment Code: 2200 
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Comment: Fourth, not only were the thyroid hormone values within normal clinical ranges, but 

urinary perchlorate levels as a surrogate for dose demonstrate that these perchlorate exposures are 

well below the threshold for zero inhibition of iodide uptake, a nonadverse effect. Exposures that 

are below the threshold for iodine uptake inhibition are below the NOEL for perchlorate and are 

not adverse (NRC, 2005; Greer et al., 2002). 

Finally, based on the premise that science is incremental and knowledge builds collectively over 

time, concerns raised by scientists related to the Blount et al. (2006) study should be considered an 

opportunity for further study. Furthermore, recognizing that urinary spot iodine or single point 

iodine measures are not a good indicator of iodine status, a different approach is being considered 

by Dr. Blount. More research should be conducted to better understand the results of this study. 

Response: See response to comment ID 29078 under comment code 2200. 

Commenter Name: Jonathan Borak 

Commenter Organization: Yale School of Medicine 

EPA Document ID: EPA-HQ-OW-2009-0297-0209 

EPA Comment ID: 29078 

EPA Comment Code: 2200 

Comment: The key findings of the Blount study are well known: 

1) Measures of thyroid function (T4 and TSH) were significantly associated with urinary perchlorate 

levels in women, but not men; 

2) T4 levels were negatively associated with urinary perchlorate levels in women with spot urine 

iodine levels <100 ug/L, but not >=100 ug/L. TSH levels were positively associated with 

perchlorate in both groups of women; 

3) Urinary thiocyanate levels were negatively associated with TSH in women with spot urine iodine 

levels >=100 ug/L, but there was no association in those with <100 ug/L. Urinary thiocyanate 

levels were not significantly associated with T4 in women with spot urine iodine levels <100 ug/L or 

>=100 ug/L; 

4) Urinary nitrate levels were negatively associated with T4 in women with spot urine iodine levels 

>=100 ug/L, but not in those with levels <100 ug/L. Urinary nitrate levels were not significantly 

associated with TSH in women with spot urine iodine levels <100 ug/L or >=100 ug/L. 

The Blount perchlorate findings are provocative, and at first seem biologically plausible. But when 

all study findings are viewed together, their pattern is inconsistent with what is generally accepted to 

be the basic physiology of the Sodium/Iodide Symporter (NIS). 

Three principal anions, perchlorate, thiocyanate and nitrate (along with other 'lesser' anions) exert 

qualitatively similar effects upon the thyroid, i.e., they competitively inhibit iodine uptake by the NIS 

(2-5). The NIS effects of these molecules have been shown repeatedly to be similar in direction and 

additive in magnitude, and their quantitative relationships have been well characterized (6-12). 
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Accordingly, it is reasonable to expect that the effects on iodine uptake of increasing exposure to 

perchlorate, thiocyanate and nitrate would be directionally similar and quantitatively predictable. 

That viewpoint is widely held by EPA scientists and others. Consider, for example, the views 

expressed in the recent report of the EPA's Office of Inspector General (OIG) (13): 

"... the human body is exposed to all three NIS inhibitors concurrently and the resulting effect on 

the uptake of iodide by the thyroid is cumulative and indistinguishable from each other ..." 

"The three NIS inhibitors (thiocyanate, nitrate, and perchlorate) exceed EPA's 'mode of action' 

requirement by sharing the same 'mechanism of toxicity' (i.e., simple competitive interaction) by 

inhibiting the uptake of iodide at the NIS..." 

Likewise, Blount et al. agree that thiocyanate, nitrate, and perchlorate share activity as competitive 

inhibitors of iodine uptake (1): 

"the ability of NIS to transport adequate amounts of iodide depends on the relative concentrations 

of these competing anions". 

Steinmaus et al. also concur (14): 

"High doses of perchlorate have been shown to competitively inhibit iodide uptake in the thyroid 

gland ... other agents, including nitrate in food and water and thiocyanate in food or from tobacco 

smoke also affect the thyroid by the same mechanism." 

De Groef et al., in consideration of expected half-lives and exposure levels of these anions, 

concluded that the anti-thyroid effect of perchlorate was similar to, but substantially smaller than the 

respective effects of thiocyanate and nitrate (12): 

"perchlorate accounts for less than 10% of possible thyroidal effects resulting from the exposure 

from drinking water; in food, its share is even negligible." 

The inconsistencies in the Blount data are shown in the following table, which indicates the 

direction of expected effects on T4 and TSH levels resulting from increased exposure to perchlorate, 

thiocyanate or nitrate, and the effects on T4 and TSH levels observed in various groups as reported 

by Blount et al. No consistent pattern of effects is seen, and observed effects are not all consistent 

with expected. 

Expected Effects and Reported Significant Effects on T4 and TSH from Increasing Exposure to 

Perchlorate, Thiocyanate and Nitrate [see table in PDF docket ID EPA-HQ-OW-2009-0297-0209] 

Also surprising is the general absence of effects attributable to thiocyanate and nitrate. As 

emphasized in the OIG analysis, "typical human exposures" to thiocyanate and nitrate should have 

induced "substantially more NIS inhibition" than that caused by 13 ug/day perchlorate exposure, 

the 95th percentile exposure level in the Blount study (13). 

Blount et al. recognized that such results were surprising: 
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"unexpected based on a mechanism of NIS inhibition. The explanation for this is unclear"(1). 

Although various hypothetical and speculative explanations were proposed for such apparent 

inconsistency, I am not aware that any has actually been validated. 

Steinmaus et al., in their re-analysis of the NHANES and Blount data, evaluated the impact of 

urinary thiocyanate levels on the associations between urinary perchlorate and thyroid function 

noted by Blount et al. (14). Like Blount, they found no significant effects in males and no significant 

effects in women with urinary iodine levels >=100 ug/L. And also like Blount, they recognized and 

could not explain the inconsistencies of their results. They could not explain the observed genderspecificity: 

"We do not know why the effects we identified were seen only in women". 

Similarly, they could not explain the absence of effects for nitrate, which "requires investigation 

beyond the scope of this paper". Finally, they could not explain the absence of perchlorate- and 

thiocyanate-related effects in women with spot urine iodine levels >=100 ug/L. 

It is not known whether the inconsistent results reported in Blount and Steinmaus reflect yet-to-beelucidated physiological relationships, heretofore unrecognized sources of confounding, or just 'bad 

luck' that adversely impacted the composition of the study cohort. Whichever, it is apparent that 

these data are not adequate to serve as the basis for regulatory rule making. There are too many 

inexplicable scientific uncertainties that can only be addressed by hypothetical and speculative 

thinking. Moreover, it is unlikely that reanalysis of the 2001-2002 NHANES data and Blount 

analyses can resolve these concerns, nor can the Steinmaus et al. analysis be used to validate the 

Blount et al study, as emphasized in the OIG report (13): 

"the Steinmaus analysis does not corroborate the Blount analysis because both studies use the same 

NHANES 2001-2002 data set." 

In summary, the Blount et al. and Steinmaus et al. studies are provocative and useful as the bases for 

hypothesis generating. They are not, however, adequate for hypothesis testing and their conclusions 

remain too speculative and uncertain to provide a sound basis for regulation. 

Response: EPA has evaluated the Blount and Steinmaus papers as well as the OIG report cited by 

the commenter. EPA has determined that these studies and report are informative, but the Agency 

believes the recommendations of the NRC represent the best available peer reviewed science on 

which to base a regulatory determination. EPA believes the NRC appropriately based the RfD on 

iodide uptake inhibition to the thyroid, for the reasons discussed in its report. See further discussion 

of the RfD in today’s Federal Register notice. With respect to effects of nitrate and thiocyanate, data 

do not exist at this time to permit a quantitative assessment of potential cumulative effects of 

perchlorate and other compounds that impact the sodium iodide symporter. However, EPA has 

committed to a drinking water strategy that outlines four principles to expand public health 

protection for drinking water (USEPA, 2010b). One of these principles is to address contaminants 

as groups. However, EPA does not believe that regulatory action to address perchlorate should be 

further delayed. Therefore, EPA intends to develop a proposed rule for perchlorate. EPA will 

continue to analyze the best available science in developing the proposed rule. 
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EPA Comment Code: 2300 Use of PBPK models from Clewell et al (2007) and 

Merrill et al (2005) to evaluate health effects 

Response to Comment Code 2300: EPA reviewed, modified, and applied the perchlorate 

Physiologically-Based Pharmacokinetic (PBPK) models, which were originally developed by Merrill 

et al. (2005) for adults and Clewell et al. (2007) for other life stages, to estimate the iodide uptake 

inhibition in the thyroid for each life-stage (73 FR 60262; USEPA 2008a). Estimated ingestion rates 

were then used to estimate the internal dose and resulting iodide uptake inhibition for several life 

stages, including susceptible populations (e.g., pregnant women and their fetuses, as well as breastfed and bottle-fed infants). 

In the August 2009 notice, EPA stated that it was re-evaluating how best to incorporate the PBPK 

modeling analysis into its evaluation of perchlorate — if at all. The Agency sought comments on 

ways to use the PBPK modeling analysis to inform the regulatory determination. 

Several commenters supported the use of the PBPK model to inform the regulatory determination 

only if the significant limitations of the current model are addressed. For example, the inability of 

the model to reflect iodide nutritional status was cited by commenters and three of four peer 

reviewers as an important limitation (USEPA, 2008d). Also, several commenters stated that the risks 

to breast-fed infants and young children are not adequately addressed by the model. They challenged 

that the modeling analysis is based on average weight infants and healthy adults, while the sensitive 

life stages for perchlorate include premature infants and hypothyroid women. 

After further consideration of the peer review and public comments, EPA concludes that the PBPK 

modeling analysis, in the context of the perchlorate regulatory determination, is useful in examining 

which life stages are most susceptible to the effects of perchlorate. For example, the model indicates 

that a fetus may be seven times more sensitive to the effects of perchlorate than a pregnant woman. 

The model also allows for the estimation of the concentration of perchlorate in breast milk (thus 

breast-fed infant exposure) at various maternal perchlorate exposure levels. However, because of the 

stated limitations, EPA has decided the model does not directly bear on the current decision 

regarding the need for a NPDWR for perchlorate. EPA is continuing to evaluate whether the model 

could be used in setting a NPDWR for perchlorate. 

Individual Comments 

Commenter Name: Rebecca Downey 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1888 

EPA Comment ID: 20773 

EPA Comment Code: 2300 

Comment: This decision has been based in large part on an unvetted, industry funded computer 

model. Any studies of this kind are highly suspect and must be verified by proper scientific studies. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. This model has been extensively vetted, with publication of the 
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perchlorate specific model (Clewell et al. 2007) in a reputable journal. In addition, EPA has 

subjected the modified model to peer review and revised the model in accordance with peer 

reviewer recommendations. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20899 

EPA Comment Code: 2300 

Comment: Instead of using state of the art science and human bio-monitoring data from the 

Centers For Disease Control and Prevention (CDC) to assess risks, the agency employs a highly 

questionable, non-peer reviewed computer model developed by the discredited industry front group, 

the Chemical Industry Institute of Toxicology (CIIT). The choice to use a model instead of real 

world data was done for one reason, to make the risks from perchlorate look smaller than they really 

are. The model did achieve that result, but even this faulty analysis did not completely exonerate this 

potent thyroid toxin. In the end, this computer model predicts that 30,000 pregnant women would 

be exposed to perchlorate in drinking water at levels that exceed EPA’s health reference level (HRL) 

of 15 ppb at any given time (EPA 2008). 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. EPA acknowledges the Blount et al (CDC) analysis of effects of 

perchlorate on the thyroid status of women with low urinary iodide. However, the applicability of 

the analysis is limited by deficiencies noted by the authors. See response to comment code ID 28515 

under comment code 2200. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20904 

EPA Comment Code: 2300 

Comment: Other noteworthy errors and flaws in this assessment include the following: 

* The physiologically-based PBPK model that EPA uses in their assessment was designed by 

researchers who work for the CIIT, an industry funded research organization with a history of 

providing assessments to EPA that favor industry interests; 

* The PBPK model that EPA uses in their assessment relies heavily on the flawed, industry-funded 

Greer study; 

* EPA essentially ignores data from large, well-conducted human studies in favor of a PBPK 

computer model; 

Response: 

See response to comment code 2300 for a discussion of PBPK modeling in and considerations in 

this regulatory determination. EPA acknowledges the Blount et al. analysis of effects of perchlorate 

on the thyroid status of women with low urinary iodide. However, the applicability of the analysis is 
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limited by deficiencies noted by the authors. See response to comment ID 28515 under comment 

code 2200. 

See also response to comment ID 20899 under comment code 2300. 

 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20910 

EPA Comment Code: 2300 

Comment: EPA relies on PBPK model that was designed by industry-funded group: EPA relies 

heavily on the PBPK model in their assessment; this model was designed in part by scientists who 

work for the CIIT, which is an industry-funded organization that is sponsored by corporations such 

as 3M, BASF, Dow, and ExxonMobil and trade groups such as the American Chemistry Council 

and the American Petroleum Institute. 

The CIIT has a history of conducting assessments that result in outcomes that favor industry. In a 

2008 report, the Government Accountability Office (GAO) notes that the CIIT developed a risk 

assessment for formaldehyde that was 2,400 times less stringent than a previous Integrated Risk 

Information System (IRIS) estimate (GAO 2008). The GAO report goes on to note "The decision 

to use the CIIT assessment in the plywood national emissions standard was controversial, and 

officials in EPA’s National Center for Environmental Assessment said the center identified 

numerous problems with the CIIT estimate" (GAO 2008). 

In 2004 the CIIT also published a model for the contaminant trichloroethylene (TCE) that proposed 

cancer risk values for TCE inhalation that were 300 times less protective than EPA's 2001 proposed 

values (Clewell et al. 2004). Leading EPA researchers subsequently published a critique of the CIIT's 

work, stating that their literature review did not present a "sufficiently current, complete, accurate, 

and transparent review of the pertinent literature," and concluding that the resulting model had not 

been adequately described or validated (Caldwell et al. 2006). EPA scientists also noted that the CIIT 

had failed to disclose their funding for the TCE model, and inappropriately implied that it had been 

funded by EPA. 

In addition, EPA itself has noted errors in the CIIT PBPK model used in the perchlorate 

assessment, explaining in their report, "EPA evaluated the PBPK model code provided by the 

model authors and found minor errors in mathematical equations and computer code, as well as 

some inconsistencies between model code files" (EPA 2008). It is unclear why EPA relies so heavily 

on the CIIT generated PBPK model when the CIIT has a history of conducting industry friendly 

assessments, as with the formaldehyde example, and there are clear errors in the perchlorate model, 

as acknowledged by EPA. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. As the commenter notes, EPA modified the model of Clewell et al. (2007) 

to correct minor mathematical errors and to expand the capabilities to reflect additional life stages. 

This work was conducted with the consent and support of the model developers. The model was 

previously peer reviewed and published in a reputable journal. 
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EPA does not believe that CIIT’s work on formaldehyde or TCE is relevant to the perchlorate 

assessment. 
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EPA Comment Code: 2400 Use of EPA’s PBPK model to evaluate health 

effects 

Individual Comments 

Commenter Name: Melanie A. Marty, Ph.D. 

Commenter Organization: Children's Health Protection Advisory Committee 

EPA Document ID: EPA-HQ-OW-2008-0692-0962 

EPA Comment ID: 20417 

EPA Comment Code: 2400 

Comment: The Agency justifies the high MRL [sic] by a pharmacokinetic model that simulates 

iodine uptake inhibition in the human fetus and newborn based upon experimental data in rat pups. 

While the model has been validated in adult humans and rat pups, it has not been validated in 

infants and children. As we described in the CHPAC 2006 letter, use of the rat data to project 

pharmacolcinetics to human newborns is uncertain given the well known differences in the rate of 

development of clearance mechanisms between rodents and humans. The modeling performed by 

the Agency does not remove the clear concern for elevated neonatal exposure to perchlorate, well in 

excess of the RfD. This also represents an unorthodox use of pharmacokinetic modeling in 

regulatory risk assessment because once an RfD is established, it is inappropriate to use additional 

modeling to justify exceeding the RfD. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection 

EPA Document ID: EPA-HQ-OW-2008-0692-1422 

EPA Comment ID: 20433 

EPA Comment Code: 2400 

Comment: 4. The PBPK Model is Uncertain Especially for Iodine Insufficient Women. Instead of 

using the standard approach of comparing estimated doses to the RfD to determine safe drinking 

water levels, EPA is instead relying on physiologically-based pharmacokinetic (PBPK) modeling to 

predict IUI. MassDEP believes that the PBPK modeling has a number of limitations and may be 

less reliable. For example, the PBPK modeling does not adequately address effects in iodide 

insufficient populations and is very uncertain with respect to predicted breast milk perchlorate 

concentrations, effects on neonates and impacts during early fetal development. Empirical data on 

these issues is sparse, limiting model construction and evaluation. More robust uncertainty analysis 

and evaluation of model outputs is needed. 

5. EPA Needs to Better Assess and Present PBPK Model Uncertainties. Since EPA relies heavily on 

the outputs of the PBPK model to predict breast milk perchlorate levels, a more thorough 

presentation of the model, model uncertainties and its outputs, in particular for breast milk 

perchlorate concentrations and neonatal exposures under differing maternal exposure scenarios is 

needed. This information should be provided to the public for review and comment, in addition to a 
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scientific peer review session. These are uncertain because the PBPK model relied on rat data for 

several key parameters that influence breast milk perchlorate concentrations. Furthermore, the 

model was only evaluated against limited human data derived from populations in Chile (Tellez et 

al., 2005). 

6. US Data Indicates the PBPK Model May Underestimate Breast Milk Perchlorate. Due to 

differences in dietary iodide intake rates, which are likely to be much higher in Chile, as well as other 

factors, breast milk data from US populations with lower levels of iodine intake, such as from the 

Boston study (Pearce et al., 2007), should also be used for model evaluation. Based on the Pearce et 

al., study, MassDEP is concerned that the model may significantly underestimate perchlorate breast 

milk concentrations in US women. Table 1, compiled by MassDEP, compares observed perchlorate 

and iodide concentrations in breast milk and perchlorate in urine from the Chilean and Boston study 

populations. These data are consistent with higher dietary iodide intake levels in the Chilean 

populations compared to the Boston area. The US data also exhibits a higher breast milk to urine 

perchlorate concentration ratio compared to those observed in the Chilean study groups - a factor of 

4 for the Boston data vs. a range of only 0.33 to 2 for the Chilean populations. This suggests that the 

Boston women, perhaps due to lower iodide intake, may have partitioned a greater fraction of 

perchlorate dose into breast milk than predicted by the model. This would result in even higher 

neonatal exposures than predicted by EPA at a maternal drinking water concentration of 15 ug/L, 

which as noted above, already exceeds the RfD. 

[Table 1. Lactational Perchlorate and Iodide levels in Urine and Breast Milk - see PDF Docket ID 

EPA-HQ-OW-2008-0692-1422] 

7. The PBPK Model is Deficient for Early Developmental Periods. Emerging data now indicate that 

thyroid hormone deficiency during early gestation causes neuronal toxicity (Sinah et al., 2008). The 

EPA has acknowledged that the lack of biological information during early fetal development limits 

the applicability of the PBPK modeling of the fetus and thus can not make meaningful predictions 

regarding early fetal IUI. 

8. The PBPK Model Does Not Consider Other Potential Mechanisms of Toxicity. Additionally, the 

model only addresses iodide uptake inhibition. However, perchlorate not only inhibits iodide uptake 

but also promotes the discharge of endogenous iodide, which is not addressed in EPA’s assessment. 

The thyroid gland possesses two kinds of iodide. The first is the iodide which is accumulated into 

the thyroid by an active transport mechanism, the so-called "transported iodide". The second source 

is the iodothyronins which are derived by hydrolysis from thyroglobulin and rapidly deiodinated 

within the gland to yield the so- called "endogenous iodide". It is believed that both iodide sources 

are used within the thyroid gland for the synthesis of hormones. Rosenberg et al., 1961; Isaacs et al., 

1966; Greer et al., 1969 showed that perchlorate discharged endogenous iodide in animals, and Burgi 

et al.(1974) confirmed this phenomenon to occur in humans. Wolff (1974) has attempted to propose 

mechanisms by which perchlorate accomplishes the discharge of stored thyroidal iodide, but how 

this process affects thyrocytes upon short- and long-term exposure is not well understood and is not 

covered by the PKPB modeling. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.

Commenter Name: Jeanne Herb 
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Commenter Organization: New Jersey Dept. of Environmental Protection 

EPA Document ID: EPA-HQ-OW-2008-0692-1526 

EPA Comment ID: 20448 

EPA Comment Code: 2400 

Comment: Proposed HRL of 15 ug/L for Perchlorate 

In 2006, USEPA adopted an IRIS Reference Dose (RfD) of 0.7 ug/kg/day for perchlorate, based 

on the advice of the National Research Council (NRC) Committee to Assess the Health 

Implications of Perchlorate Ingestion (2005), which had been assembled at the request of USEPA. 

The proposed Health Reference Level (HRL) for perchlorate of 15 ug/L was derived using exposure 

assumptions for a pregnant woman/fetus exposed to the RfD of 0.7 ug/kg/day with a Relative 

Source Contribution (RSC) factor of 0.6. In developing this HRL, USEPA assumed that the fetus is 

the most sensitive subpopulation, more sensitive than the infant, so that the infant can be safely 

exposed to much higher doses than the fetus. After deriving the HRL of 15 ug/L based on exposure 

of the pregnant woman/fetus, a physiologically-based pharmacokinetic (PBPK) model was used to 

evaluate the dose reaching the thyroid and to estimate effects on the inhibition of thyroidal iodine 

uptake in sensitive subpopulations exposed to 15 ug/L of perchlorate. 

Insufficient information has been provided to the public about the details of the PBPK model to 

allow for the necessary evaluation of this approach. The proposal states that USEPA modified the 

published PBPK model to reflect the decreased urinary clearance of young infants and for other 

reasons, but the citation for this information (USEPA, 2008b) does not provide a document that is 

available to the public. Additionally, USEPA states that the modifications it has made to the 

published model have not yet been peer reviewed, and that this peer review will take place prior to 

finalizing the proposal. We believe that the results of the peer review should be available as part of 

the USEPA proposal, so that the public can consider the conclusions of the peer review as to the 

appropriateness of the approach used by USEPA. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. The modifications to the Clewell (2007) model were peer reviewed and 

found to be sound. The peer review report can be found on EPA’s website at 

http://water.epa.gov/drink/contaminants/unregulated/perchlorate.cfm. The major reservation 

expressed centers on attempting to use the model beyond its capabilities. 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Dept. of Environmental Protection 

EPA Document ID: EPA-HQ-OW-2008-0692-1526 

EPA Comment ID: 20450 

EPA Comment Code: 2400 

Comment: Another matter of concern is the assumption that a 2.2% decrease in iodide uptake in 7-

day old infants can be regarded as a No Effect Level (73 Fed. Reg. 60278 (October 10, 2008)) by 

extrapolation from the NRC panel’s conclusions. The NRC based the conclusion that a 1.8% 

decrease was a No Effect Level on data from normal healthy adults. Additionally, the 1.8% decrease 

was considered to be within the normal variation expected in an experimental measurement, which 

differs in concept from a prediction of a decrease of any magnitude by a model. Although iodide 
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uptake by the thyroid in healthy infants functions at a level similar to adults, this assumption that a 

decrease of 2.2% is inconsequential does not provide the level of protection that is usually extended 

to clearly sensitive subpopulations. Critically, infants do not achieve complete maturity of thyroid 

function until 1-2 months postnatally, display a shorter thyroxine half-life, and do not have the same 

degree of thyroid reserve capacity as healthy adults (Brown et al., 2004; van den Hove et al., 1999; 

Zoeller and Rice, 2004). While most infants with severe thyroid problems are identified within a few 

days after birth, premature infants, infants with subclinical hypothyroidism or with low iodine intake 

are not represented by the average healthy infant considered by the PBPK model. Furthermore, the 

predictions for perchlorate exposure and decreases in iodide uptake are only averages for the group 

considered, normal healthy infants, and the range that could be predicted by the model due to 

differences in pharmacokinetic and pharmacodynamic factors is not given. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. 

Commenter Name: Robert Howd 

Commenter Organization: California Environmental Protection Agency, Water Toxicology 

Section 

EPA Document ID: EPA-HQ-OW-2008-0692-1671 

EPA Comment ID: 20647 

EPA Comment Code: 2400 

Comment: III (A)(3), pp 60268-9. The elegant PBPK model of Clewell et al. (2007) represents a 

significant advance in understanding potential perchlorate effects on the human maternal/fetal unit, 

and the maternal to infant passage of perchlorate and iodide through mother’s milk. However, some 

of the parameters in this model are inadequately understood and documented. The adaptations 

utilized by EPA (U.S. EPA, 2008) appear to improve the model, but we are concerned that it may 

not sufficiently address fetal and infant iodide/perchlorate ratios and potential effects on thyroid 

hormone regulation. We believe that more review of the model and its interpretation are needed, 

especially considering potential inhibition of fetal iodide uptake in mothers with low iodide 

consumption (i.e., maternal/fetal variation). 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.

Commenter Name: Robert Howd 

Commenter Organization: California Environmental Protection Agency, Water Toxicology 

Section 

EPA Document ID: EPA-HQ-OW-2008-0692-1671 

EPA Comment ID: 20650 

EPA Comment Code: 2400 

Comment: IV (B)(5), pp 60277-9. PBPK modeling. Critical parameters such as relative transport of 

iodide and perchlorate across the placenta and uptake into fetal thyroid are not yet available. We 

therefore would judge these calculations and conclusions very cautiously. 

For estimation of infant’s exposure to formula on p. 60279, the EPA has referred to their new 

evaluation of the data from the 1994-96 and 1998 Continuing Survey of Food Intakes by 
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Individuals, by Kahn and Stralka, which was recently published online in the Journal of Exposure 

Science and Environmental Epidemiology. We note that the values cited from this source are less 

than we have been using, based on EPA (2004), but we have not had the opportunity to compare 

the evaluations and strength of conclusions in detail. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1748 

EPA Comment ID: 20654 

EPA Comment Code: 2400 

Comment: Third, in particular, the PBPK model referenced in the letter has already been 

extensively peer-reviewed. Furthermore, the EPA is conducting an independent external letter peer 

review of a draft report prepared by EPA’s Office of Research and Development titled, Inhibition 

of the Sodium-Iodide Symporter by Perchlorate: An Evaluation of Lifestage Sensitivity Using 

Physiologically-based Pharmacokinetic (PBPK) Modeling. This review is expected to be completed 

shortly. The underlying model and its expansions are already the subject of four peer-reviewed, 

published scientific articles.[FN5: Rebecca A. Clewell et al., The Use of Physiologically-Based 

Models to Integrate Diverse Data Sets and Reduce Uncertainty in the Prediction of Perchlorate and 

Iodide Kinetics Across Life Stages and Species, Toxicol. Ind. Health, 2001, 210-222; Rebecca A. 

Clewell et al., Predicting Fetal Perchlorate Dose and Inhibition of Iodide Kinetics During Gestation: 

A Physiologically-Based Pharmacokinetic Analysis of Perchlorate and Iodide Kinetics, 2003, 

Toxicol. Sci., 2003, 235-55; Elaine A. Merrill et al., PBPK Model for Radioactive Iodide and 

Perchlorate Kinetics and Perchlorate-Induced Inhibition of Iodide Uptake in Humans, Toxicol. Sci., 

2005, 25-43; Rebecca A. Clewell et al., Perchlorate and Radioiodide and Kinetics Across Life Stages 

in the Human: Using PBPK Models to Predict Dosimetry and Thyroid Inhibition and Sensitive 

Subpopulations Based on Developmental Stage, J. Toxicol. Envtl Health, 2007, 408-28.] 

Significantly, the NAS panel endorsed it as "the best available approach" for determining effects in 

sensitive subpopulations where experimentation is impossible. While we are not aware of the 

particular changes EPA staff made to the PBPK model for use in the preliminary determination, the 

Federal Register notice provides an estimate of predicted changes in iodine uptake inhibition (IUI) 

in sensitive subpopulations that do not differ significantly from the published findings in Clewell et 

al. (2007). The results of this modeling estimate that certain sensitive populations (although not the 

most sensitive population, which are pregnant women and their fetuses) may have exposures in 

excess of the RfD. However, these groups would have minimal IUI at environmental doses. These 

conclusions are important enough to state again: even at doses greater than the reference dose, 

sensitive subgroups within the population may have minimal changes in their IUIs. The magnitudes 

of these changes are small enough to be attributable to normal fluctuations, possibly from diet. As 

noted by the NAS review, unless there is a sustained and significant change in IUI, adverse effects 

from perchlorate will not occur.[FN6: See Note 1.] 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.

Commenter Name: Caroline Baier-Anderson, PhD 
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Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20950 

EPA Comment Code: 2400 

Comment: A major concern is that the application of the PBPK model after the establishment of 

an RfD is a novel concept that must be thoroughly vetted prior to using in the regulatory setting. 

EPA should convene a peer review process to evaluate this novel use of a PBPK model, not just for 

use in developing a health advisory level for perchlorate, but its use in the general sense. Such 

deviations from the standard risk-based approaches must be thoroughly evaluated, with 

recommended applications and limitations clearly identified. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20968 

EPA Comment Code: 2400 

Comment: EPA seems to aim to limit uncertainties as much as is possible by taking into account 

the latest available evidence such as the NHANES data and make use of sophisticated models such 

as the FDA TDS and the PBPK models. This is laudable. 

Response: EPA has assessed the available scientific information on health effects and exposure to 

perchlorate. See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20997 

EPA Comment Code: 2400 

Comment: 3. EPA ignores fails to adequately consider evidence that the proposed HRL is not safe 

Although EPA's scientific staff issued a rigorous review of the PBPK model and its findings, the 

Agency has ignored the most important conclusions of the report, that infants and young children 

will have a perchlorate intake that exceeds the RfD. Instead, the preliminary determination seems to 

suggest that the PBPK model results support the Agency's proposed HRL. This is not the case. 

A. The PBPK model provides evidence that at the proposed HRL, infants and young children will 

have a perchlorate intake that exceeds the reference dose. 

The EPA scientific staff conducted a rigorous evaluation of the application of the physiologicallybased pharmacokinetic (PBPK) model, particularly as it applies to sensitive life-stages.[FN49: EPA 

Office of Research and Development. Inhibition of the sodium-iodide symporter by perchlorate: An 
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evaluation of lifestage sensitivity using physiologically-based pharmacokinetic (PBPK) modeling. 

Preliminary Draft. October 2, 2008. EPA/600/R-08/106A. Docket ID No. EPA-HQ-OW-2008-

0692-0076.] On October 2, 2008, EPA issued the report, which identifies some very troubling 

findings, including evidence that consuming water that was contaminated at the HRL of 15 ug/L 

would lead to bottle-fed infants exceeding the reference dose by 5-fold and young children 

exceeding the reference dose by 2.8-fold, based on average food contamination rates, average body 

weights, and 90th percentile water consumption rates for each age group (Staff Report, Table 

4).[FN50: EPA Office of Research and Development. Inhibition of the sodium-iodide symporter by 

perchlorate: An evaluation of lifestage sensitivity using physiologically-based pharmacokinetic 

(PBPK) modeling. Preliminary Draft. October 2, 2008. EPA/600/R-08/106A. Docket ID No. 

EPA-HQ-OW-2008-0692-0076.] Specifically, the staff report found that the PBPK model predicted 

the perchlorate intake (ug/kg-day) from average food consumption, and 90th percentile water 

consumption held to 15 ug/L perchlorate as shown in Table 1. The table also identifies the 

magnitude by which the RfD is exceeded at the proposed HRL. 

[Table 1: Perchlorate intake at a Health Reference Level of 15 ug/L - see PDF Docket ID EPAHQ-OW-2008-0692-????] 

These values were also reported in the Federal Register notice, Table 8.[FN51: 73 Fed. Reg. at 

62078.] Note that the overwhelming majority of perchlorate for these age groups is coming from 

water or breast milk, and not from solid food. These data, generated from the PBPK model 

predictions, provide substantial scientific support for the conclusion that infants (both breast- and 

bottle-fed) and young children would exceed the reference dose if their dietary water were 

contaminated with perchlorate at the HRL. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 21001 

EPA Comment Code: 2400 

Comment: B. PBPK model supports an uncertainty factor of at least 15-fold 

EPA normally uses a 10-fold default uncertainty factor to adjust for variations among individuals, 

called the intraspecies factor, when the Agency lacks adequate data to calculate intra-individual 

variability. EPA used this 10X intraspecies factor for its perchlorate hazard assessment on its IRIS 

database: "An intraspecies uncertainty factor of 10 is applied to protect the most sensitive 

population, the fetuses of pregnant women who might have hypothyroidism or iodide 

deficiency."[FN58: EPA. IRIS database. Perchlorate and perchlorate salts. 

http://www.epa.gov/ncea/iris/subst/1007.htm#revhis] The Agency has adopted the practice of 

describing the default 10-fold intraspecies factor as being comprised of the product of two 3-fold 

factors, one for pharmacokinetic variability, and the other for pharmacodynamic variability.[FN59: 

US EPA. Office of the Science Advisor: Staff Paper, Risk Assessment Principles & Practices. Page 

69, Section 4.3.2. EPA/100-B-04/001. March, 2004. http://www.epa.gov/osa/pdfs/ratffinal.pdf] 

Pharmacokinetics describes the way that a compound such as perchlorate moves through the body, 
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including its absorption, distribution, metabolism and excretion. In contrast, pharmacodynamics 

describes what the compound does in the body, including depressing, stimulating, irritating, or 

killing cells or systems. 

According to the IRIS glossary of terms, a PBPK model estimates the dose of a compound to a 

target organ or tissue by calculating the rate of absorption in the body, the distribution among target 

organs, the metabolism of the compound, and the excretion of the compound.[FN60: IRIS 

Glossary. Physiologically Based Pharmacokinetic (PBPK) Model. 

http://www.epa.gov/ncea/iris/help_gloss.htm#p] In other words, the PBPK model, by definition 

and design, estimates the pharmacokinetics of a compound. 

The data from EPA's staff report however, shows that EPA's reliance on a default uncertainty factor 

of 10 underestimates the variability between fetuses and adults. The Executive Summary of the staff 

report states that "at a perchlorate dose of 7 ug/kg-day [the RfD], the percent RAIU inhibition 

predicted by the model for the near-term fetus is 5-fold greater than the average adult...The same 

analysis predicts percent RAIU inhibition approximately 1-2 fold higher for the breast-fed and 

bottle-fed infant (7-60 days) than for the average adult."[FN61: See EPA Staff Paper, Table 3; see 

also 73 Fed. Reg. 60278.] More specifically, for perchlorate, the variability between a near-term fetus 

(40 weeks gestation) and an adult is 5.3-fold, Therefore, the PBPK model supports a 

pharmacokinetic adjustment factor of at least 5-fold. 

The Agency has no information from the PBPK model, or from other data, to develop an 

intraspecies uncertainty factor for pharmacodynamic variability, particularly between adults and 

sensitive lifestages. Therefore, EPA should retain a 3-fold default factor for pharmacodynamic 

uncertainty, consistent with its current practice. 

Using the data from the PBPK model to support a pharmacokinetic intraspecies variability factor of 

5, and the lack of pharmacodynamic data to support a default factor of 3, then the total intraspecies 

uncertainty factor should be (5 x 3) 15-fold, which is consistent with EPA policy and practices, and 

is supported by the available data. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. The modeled estimates of alternative HRLs reflect only pharmacokinetics 

and do not consider uncertainty due to pharmacodynamics. Pharmacodynamics is dose description 

of the dose-dependent effect of a chemicals on the target organ. Pharmacodynamics may vary by life 

stage. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-2082 

EPA Comment ID: 21020 

EPA Comment Code: 2400 

Comment: 3. Your letter also raises a concern that the PBPK model has been only validated in 

adult humans and rat pups, not in infants and children, adding that use of rat data to project 

pharmacokinetics to human newborns is uncertain given the differences in the rate of development 

of clearance mechanisms between rodents and humans. 
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PBPK modeling is the best method today to address sensitive populations when testing is not 

possible or ethical. In fact, the PBPK model referenced has already been extensively peer reviewed, 

including via modeling conducted on sensitive populations. 

To be specific, the underlying model and its expansions are the subject of four peer-reviewed, 

published scientific articles [FN1: Rebecca A. Clewell et al., The Use of Physiologically-Based 

Models to Integrate Diverse Data Sets and Reduce Uncertainty in the Prediction of Perchlorate and 

Iodide Kinetics Across Life Stages and Species, Toxicol. Ind. Health, 2001, 210-222; Rebecca A. 

Clewell et al., Predicting Fetal Perchlorate Dose and Inhibition of Iodide Kinetics During Gestation: 

A Physiologically-Based Pharmacokinetic Analysis of Perchlorate and Iodide Kinetics, 2003, 

Toxicol. Sci., 2003, 235-55; Elaine A. Merrill et al., PBPK Model for Radioactive Iodide and 

Perchlorate Kinetics and Perchlorate-Induced Inhibition of Iodide Uptake in Humans, Toxicol. Sci., 

2005, 25-43; Rebecca A. Clewell et al., Perchlorate and Radioiodide and Kinetics Across Life Stages 

in the Human: Using PBPK Models to Predict Dosimetry and Thyroid Inhibition and Sensitive 

Subpopulations Based on Developmental Stage, J. Toxicol. Envtl Health, 2007, 408-28.]. Further, 

EPA is conducting an independent external letter peer review of a draft report prepared by EPA’s 

Office of Research and Development titled, Inhibition of the Sodium-Iodide Symporter by 

Perchlorate: An Evaluation of Lifestage Sensitivity Using Physiologically-based Pharmacokinetic 

(PBPK) Modeling. This review is expected to be completed shortly. 

While we are not aware of the particular changes EPA staff made to the PBPK model for use in the 

preliminary determination, the Federal Register notice provides an estimate of predicted changes in 

iodine uptake inhibition (IUI) in sensitive subpopulations that do not differ significantly from the 

published findings in Clewell et al. (2007). The results of this modeling estimate that certain sensitive 

populations (although not the most sensitive population, which are pregnant women and their 

fetuses) may have exposures in excess of the RfD. 

However, these groups would have no significant inhibition of IUI at environmental doses. These 

conclusions are important enough to state again: even at doses greater than the reference dose, 

sensitive subgroups within the population may have minimal changes in their IUIs. The magnitudes 

of these changes are small enough to be attributable to normal fluctuations, possibly from diet. The 

critical study chosen by the NAS to base its recommended RfD on, Greer et al. (2002) reported no 

IUI (1.8% ± 8.3) which was determined not to inhibit the first effect - a non adverse, fully reversible 

biochemical reaction - in the cascade of biochemical events. The PBPK modeling estimated that 

infants may have IUI as great as 2.2% at this dose, however, this value is well within normal 

variability and does not suggest that perchlorate is causing any inhibition of IUI that is different 

from Greer et al. (2002) and is supportive of other similar information regarding the affinity of 

perchlorate to the NIS. 

As noted by the NAS review, unless there is a sustained and significant change in IUI, adverse 

effects from perchlorate will not occur.[FN2: National Academy of Sciences, Health Implications of 

Perchlorate Ingestion, 2005, at 165 (pdf version).] 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. EPA agrees that the modifications to the Clewell (2007) model were peer 

reviewed and found to be sound. The peer review report can be found on EPA’s website at 

http://water.epa.gov/drink/contaminants/unregulated/perchlorate.cfm. 
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Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-2082 

EPA Comment ID: 21021 

EPA Comment Code: 2400 

Comment: 4. Also concerning PBPK Modeling, your letter suggests that EPA’s application of the 

PBPK modeling is "unorthodox" in regulatory risk assessment because it should not be used to 

exceed an established RfD. However, EPA’s use of the modeling is not used to exceed the RfD in 

this case, but rather to validate the benchmark of 15 ug/L as the HRL, and supports the point that 

the HRL derived by the Agency is even more health protective than the already conservative NASbased RfD that has been adopted by EPA. EPA policy has been to use PBPK modeling for 

determining human equivalent exposures (HEEs) and adjusting default uncertainty factors [FN3: 

U.S. EPA Risk Assessment Forum, A Review of the Reference Dose and Reference Concentration 

Process, December 2002.] Significantly, the NAS perchlorate panel agreed with EPA in finding 

PBPK modeling is "the best available approach" in determining effects in sensitive populations 

where experimentation is impossible (NAS, 2005) [FN4: The NAS panel also concluded the 

following: "By applying factors for life-stage differences (such as pregnant or lactating female rat vs. 

adult male rat) and for species differences (such as adult rat vs. adult human or pregnant or lactating 

rat vs. pregnant or lactating human), one can constrain PBPK simulations by using known 

physiologic measures and biochemical constants to estimate HEEs in potentially sensitive 

populations that may not be suitable for experimental validation."] EPA personnel have co-authored 

studies involving PBPK modeling and perchlorate (Merrill et al., 2005) and present for this 

preliminary determination, a model from Clewell et al. (2007) that was modified by making coding 

changes which served to improve the predictability of the model and therefore its overall usefulness. 

With this modified model, EPA is able to predict doses and changes in RAIU in pregnant women, 

fetuses, infants, and young children. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. See response to comment code 5220 for a discussion of alternative health 

reference levels. The modifications to the Clewell (2007) model were peer reviewed and found to be 

sound. The peer review report can be found on EPA’s website at 

http://water.epa.gov/drink/contaminants/unregulated/perchlorate.cfm. 

EPA agrees that significant uncertainty in risk estimates remains whether or not the PBPK model is 

used. However, trading one uncertain estimation technique for another does not reflect progress 

unless the change sheds light on significant sources of uncertainty in the risk estimate. Given the 

incomplete nature of the PBPK model, i.e., the lack of representation of pharmacodynamics and 

differential life stage impact, and incomplete representation of pharmacokinetics, evaluating 

differential uncertainty between traditional approaches and the PBPK model referenced in the 

October 2008 FRN appears to have limited if any value. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21053 
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EPA Comment Code: 2400 

Comment: 2. Perchlorate and Human Health in 2008: The EPA Preliminary Determination. These 

comments include two sections. The first relates to scientific policy issues. Particular focus is placed 

on pharmacodynamic (PBPK) modeling. Several reports in the general circulation press have 

suggested incorrectly that PBK modeling is unfamiliar in perchlorate risk assessment. These 

comments document that the PBPK modeling has been recognized by EPA and endorsed by the 

NAS for its effectiveness in reducing scientific uncertainty. 

These comments conclude with a review of the statutory criteria establishing EPA's authority in this 

proceeding. Citing the NAS report as well as subsequent studies, the comments demonstrate that the 

Agency is correct that none of the three criteria required for setting an NPDWR are met in this case. 

Thank you for the opportunity to comment on these important issues. Please do not hesitate to 

contact me or Dr. Richard C. Pleus, if we can provide additional information or perspective in your 

deliberations. 

Sincerely, Michael Girard Chairman, Perchlorate Study Group 

Response: The commenter is correct that application of PBPK modeling to EPA risk assessments 

is increasing, and that it has the potential to inform estimation of adverse effects and dosimetry 

across a broad range of questions. See response to comment code 2300 for a discussion of PBPK 

modeling in this regulatory determination. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21100 

EPA Comment Code: 2400 

Comment: VII. The Published, Peer-Reviewed PBPK Model is Part of the Best Available Science 

EPA Can Use for the Determination 

One uncertainty in the derivation of the HRL as well as in the literature database is the lack of 

studies that measure radioactive iodine uptake (RAIU) in the sensitive population, pregnant women 

and the developing fetus. Obviously, it would be unethical to conduct such as study. However, 

Physiologically Based Pharmacokinetic (PBPK) modeling has been found to be useful in reducing 

uncertainty and in filling scientific gaps in human health data on a substance. EPA policy has been 

to use PBPK modeling for determining human equivalent exposures (HEEs) and adjusting default 

uncertainty factors.[FN5: U.S. EPA Risk Assessment Forum, A Review of the Reference Dose and 

Reference Concentration Process, December 2002.] The NAS perchlorate panel agreed with EPA in 

finding PBPK modeling is "the best available approach" in determining HEEs (NAS, 2005).[FN6: 

The NAS panel also concluded the following: "By applying factors for life-stage differences (such as 

pregnant or lactating female rat vx adult male rat) and for species differences (such as adult rat vs 

adult human or pregnant or lactating rat vs pregnant or lactating human), one can constrain PBPK 

simulations by using known physiologic measures and biochemical constants to estimate HEEs in 

potentially sensitive populations that may not be suitable for experimental validation."] EPA 

personnel have co-authored studies involving PBPK modeling and perchlorate (Merrill et al., 2005) 
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and present for this preliminary determination, a model from Clewell et al. (2007) that was modified 

by making coding changes which served to improve the predictability of the model and therefore its 

overall usefulness. With this modified model, EPA is able to predict doses and changes in RAIU in 

pregnant women, fetuses, infants, and young children. 

[Text Box: The utility of PBPK modeling has been previously recognized by EPA and has been 

endorsed by the NAS for use in reducing scientific uncertainty.] 

Using a 90th percentile water intake and based on data specifically for a pregnant woman, the model 

predicted that, 

...the pregnant woman's dose of perchlorate would not exceed the reference dose if she consumed 

drinking water with a concentration of 15 ug/L or less, which is consistent with the derivation of the 

HRL from the reference dose, but based on average body weight, 90th percentile water 

consumption, and 90th percentile food exposure for pregnant women. (73 FR 60280) 

The model verified that exposures to 15 ppb of perchlorate in drinking water will not reduce RAIU 

significantly, even assuming concurrent exposure through food and water intake in the 90th 

percentile. This combination of high-end exposure assumption is highly unlikely, probably at the 

extreme end of the population distribution. For this hypothetical pregnant woman, the percent 

RAIU inhibition was 1.1%. The greatest inhibition was seen in 7 day old infants at 2.2%. These 

percent inhibitions are consistent with the 1.8% inhibition of iodine uptake from the Greer et al. 

(2002) No Observed Effect Level (NOEL). In fact, although 2.2% is greater than 1.8% found in 

Greer et al., (2002), it is well within the standard error from Greer et al. (2002) of 8.3% and would 

still constitute a NOEL. The NAS report noted that "the very small 1.8% decrease in thyroid 

radioiodide uptake identified in Greer was well within the normal variation, and therefore 1.8% IUI 

does not define the limit beyond which adverse effects occurs has has been incorrectly argued. The 

PBPK modeling is in accord with results from other corroborative studies, such as Tellez et al. 

(2005), which show no adverse effect on sensitive populations. 

In summary, EPA's PBPK modeling supports the point that the HRL derived by the agency is even 

more health protective than the already conservative NAS-based RfD that has been adopted by 

EPA. The modeling provides scientific support that incorporating an additional level of 

conservatism in deriving an HRL is unnecessary as the RfD is already very conservative; based on 

this support, a National Primary Drinking Water Regulation would not provide a meaningful 

reduction in risk. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. . 

The commenter is correct that application of PBPK modeling to EPA risk assessments is increasing, 

and that it has the potential to inform estimation of adverse effects and dosimetry across a broad 

range of questions. EPA also agrees that the modifications to the Clewell (2007) model were peer 

reviewed and found to be sound. The peer review report can be found on EPA’s website at 

http://water.epa.gov/drink/contaminants/unregulated/perchlorate.cfm. 

Commenter Name: Mark S. Mayer 
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Commenter Organization: South Dakota Department of Environment & Natural Resources 

(DENR) 

EPA Document ID: EPA-HQ-OW-2009-0297-0467 

EPA Comment ID: 28481 

EPA Comment Code: 2400 

Comment: Specific Comments Requested by EPA: 

- Comments on Use of Physiologically-Based Pharmacokinetic Model - South Dakota DENR does 

not have toxicologists and health effect/risk analysis experts on staff to make our own regulatory 

determinations for contaminant levels, but instead relies upon EPA to establish contaminant levels 

that are supported by a strong scientific basis and cost effective health benefits. 

Response: The Safe Drinking Water Act requires EPA to use the best available, peer reviewed 

science in support of its decision. EPA will adhere to this requirement developing a proposed 

national primary drinking water regulation including a health risk reduction cost analysis. 

Commenter Name: James D. Taft 

Commenter Organization: Association of State Drinking Water Administrators 

EPA Document ID: EPA-HQ-OW-2009-0297-0525 

EPA Comment ID: 28497 

EPA Comment Code: 2400 

Comment: ASDWA Responses to Specific Requests for 

Comment: 

Comments on Use of the Physiologically-Based Pharmacokinetic Model (PBPK) - ASDWA does 

not have any detailed comments to offer on the use of the PBPK model to evaluate or predict the 

health impact of perchlorate or about how this information could support a regulatory 

determination. State drinking water programs, with a few exceptions, do not have toxicologists or 

other health effect and risk analysis experts on their staffs to provide detailed evaluations of these 

issues. That is why very few states adopt their own regulatory standards but rely on EPA to set 

appropriate Maximum Contaminant Levels (MCLs). As stated earlier, ASDWA expects EPA to use 

sound scientific data from peer reviewed research to make regulatory determinations. States must 

explain to water systems and the public how the resulting MCLs protect public health and a strong 

scientific basis for the rule makes that justification credible. We do appreciate the rigor with which 

the Agency has explored this issue and the range of options being considered in connection with the 

PBPK model as well as the evaluation of the relative sensitivity of the various life stages to 

perchlorate exposure in drinking water. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. 

Commenter Name: Shannon Cunniff 

Commenter Organization: Department of Defense (DOD) 

EPA Document ID: EPA-HQ-OW-2009-0297-0411 

EPA Comment ID: 28521 
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EPA Comment Code: 2400 

Comment: Comment No. 4 

Section III. 2. What Were the Key Scientific Issues Raised by Commenters 

Page & Paragraph Page 41885 Col 1, Para 4 Col 2, Para 2 

Comment EPA has issued several PBPK guidance documents, including Use of Physiologically 

Based Pharmacokinetic Models to Quantify the Impact of Human Age and Interindividual 

Differences in Physiology and Biochemistry Pertinent to Risk (EPA/600/R-06/014A) and 

Approaches for the Application of Physiologically Based Pharmacokinetic Models and Supporting 

Data in Risk Assessment (EPA/600/R-05/043F), and notes at its National Center for 

Environmental Assessment webpage (http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=2044, 

accessed 15 September 2009), "Physiologically-based pharmacokinetic (PBPK) models have 

increasingly been employed in chemical health risk assessments carried out by the U.S. 

Environmental Protection Agency (EPA), and it is anticipated that their use will continue to 

increase." Given such activities and statements, it is not clear from the current notice, why the 

agency is now proposing removing the PBPK models from the evaluation of life-stage specific 

differences in susceptibility. In fact no reasons are given, other than a few commenter concerns 

about (1) the level of peer review and (2) the existence of uncertainty in the model parameters, 

neither of which provide a sound reason for discarding the models. This is particularly troubling 

given that EPA specifically released its final, peer-reviewed report on Inhibition of the SodiumIodide Symporter by Perchlorate: An Evaluation of Life Stage Sensitivity Using Physiologically 

Based Pharmacokinetic (PBPK) Modeling (EPA/600/R-08/106A) as supporting material for the19 

August 2009 Federal Register notice (accessed on 15 September 2009 at the NCEA webpage 

http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=212508#Download). In the document, 

EPA definitively concludes that with minor modifications proposed by the Agency the Clewell et al. 

(2007) and Merrill et al. (2005) PBPK models are acceptable to calculate the life stage differences in 

the degree of thyroidal NIS RAIU inhibition at a given level of perchlorate exposure. 

Suggested Action, Revision and References (if necessary) It is recommended that the PBPK models 

continue to be used in the evaluation of perchlorate life- stage susceptibility. 

Category* S. M 

 Comment No. 5 

Section III. 2. What Were the Key Scientific Issues Raised by Commenters 

Page & Paragraph Page 41885 Col 1, Para 4 

Comment The current documentation of the background for the development of the HRL gives 

significant weight to public comments regarding peer review of the models, which together with the 

lack of EPA response, gives the impression that the models have, in fact, escaped rigorous peer 

review. The background documentation suggests that peer review has been limited to eight experts 

and this is not the case. 
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Suggested Action, Revision and References (if necessary) It is recommended that the peer review of 

the models be appropriately documented. The PBPK models have undergone thorough, rigorous 

review by a variety of scientific panels comprised of experts from academia, regulatory agencies, the 

National Academies of Science, and independent consultants. Changes made to the original models 

by the EPA were independently reviewed by a panel of experts and deemed appropriate. 

Furthermore, while areas for improvement have been identified in each of the peer reviews, 

comments by the panels have always been positive and supportive of their intended use in 

identifying the susceptible life-stages for perchlorate inhibition. 

Category* E, M 

 Comment No. 6 

Section III. 2. What Were the Key Scientific Issues Raised by Commenters 

Page & Paragraph Page 41885 Col 2, Para 2 

Comment As suggested in EPA (2009), there are indeed uncertainties in some of the model 

parameters, as there is always uncertainty in any calculation of risk. The benefit of using PBPK 

models is that the uncertainty in the calculations is more transparent than the typical default 

approach. For example, it is clear from evaluation of the model output that there is not enough data 

to adequately define exposure parameters (particularly in the young neonate) and urinary clearance 

parameters. By focusing on those model parameters with uncertainty, collection of the data needed 

to improve our knowledge and reduce uncertainty can be initiated. Furthermore, the effect of these 

model parameters on the predictions of inhibition can be explored. The fact that the overall 

predictions of inhibition across life-stages were not significantly changed despite the changes made 

to the model intake and clearance parameters by the EPA indicates that the models are robust within 

the potential range of parameters made available in the data. The models help to define and decrease 

the areas of uncertainty, rather than increase them, which is what happens when the models are 

removed from consideration and life-stage comparisons are made solely on estimates of average of 

upper bound estimate of food and water intake. 

Suggested Action, Revision and References (if necessary) It is recommended that the PBPK models 

be utilized and the uncertainty analysis be performed appropriately. 

Category* S. M 

 Comment No. 7 

Section III. 2. What Were the Key Scientific Issues Raised by Commenters 

Page & Paragraph Page 41885 Col 2, Para 2 

Comment Some of the uncertainty can be addressed through the use mathematical and statistical 

tools to estimate the effect of the parameter variability on model predictions. Using statistical tools 

such as Monte Carlo analysis, we can determine ranges of inhibition expected at proposed HRLs 

while taking into account variability in the parameters. Without the models, the uncertainty still 

exists. There is still a lack of data for exposure and clearance in the HRL approach but it is not as 
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obvious. Discarding the models does not eliminate uncertainty in lifestage dosimetry, but it is hidden 

within the additional uncertainty associated with the default calculations. Reverting to the default 

approach based on external exposure concentrations in media, does not improve the estimate of risk 

or increase the likelihood of protecting the public. Rather it allows the risk assessment to be driven 

by the data that is most readily available and easiest to explain than trying to deal with the more 

difficult task of incorporating the best available science. We do view this approach as scientifically 

defensible. 

Suggested Action, Revision and References (if necessary) It is recommended that the PBPK models 

be utilized and the uncertainty analysis be performed appropriately. 

Category* S. M 

 Comment No. 8 

Section III. 2. What Were the Key Scientific Issues Raised by Commenters 

Page & Paragraph Page 41885 Col 2, Para 2 

Comment The approach previously proposed for using the models to evaluate life-stage specific 

susceptibility to iodide uptake inhibition was a reasonable use of the models. They were not used to 

derive the HRL, but were used to verify that the recommended HRL was protective of all life-stages. 

Public comments and the subsequent revised proposal appear to imply that the previous calculations 

were performed using the PBPK models. This is not the case. According to the EPA (2008), the 

models were run to provide a second, independent test for the adequacy of the proposed HRL. This 

analysis was thoughtful, novel and informative to the level of risk associated with the proposed 

HRL. It is not clear why this approach was not followed in the current assessment, particularly in 

light of the subsequent completion and positive result of the PBPK model peer review. 

Suggested Action, Revision and References (if necessary) It is recommended that the PBPK models 

be used in a reasonable approach. 

Category* S. M. 

 Comment No. 

Section III.A. 4. Request for Comment on Alternative Approaches. a., b., c. 

Page & Paragraph Page 41886 

Comment Clarity needs to be improved relative to presentation of the PBPK model results. 

It also would be helpful if the uncertainties associated with the various alternative options, such as 

use of PBPK model (e.g., iodide status, and other data deficiencies) were compared with other 

suggested methods for developing health risk levels (e.g., using human data available from "direct 

measurement") in a tabular format, to help improve the clarity of the benefits/drawbacks of the 

alternative processes. For example, uncertainty was linked to the modeling code, the availability of 

data for the many variable parameters in the model, the combination and handling of the data 
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selected for use in simulations, and, in particular, the previous lack of human data for specific life 

stages including pregnant women and their fetuses, lactating women and their babies, and bottle-fed 

infants for which rat data were adapted. The inability of the model to reflect iodide nutritional status 

also was cited by three peer reviewers as an important limitation. Recent and available "direct 

measurement" data, as cited here, for sensitive lifestages should be evaluated for potential use in 

reducing these identified areas of uncertainty. This would also help identify areas for potential future 

research. 

Suggested Action, Revision and References (if necessary) We recommend a tabular format of 

changes made to the EPA PBPK model in its last revision (May 2009) and the impact of those 

changes. 

We recommend a tabular comparison of the impact on thyroid hormone levels from recent human 

data for perchlorate, thiocyanate, nitrate and iodide in healthy populations and additional modeling 

of these data to help determine the impact of low iodide for sensitive subpopulations, such as 

pregnant women and infants. 

Category* E 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. 

The commenter is correct that application of PBPK modeling to EPA risk assessments is increasing, 

and that it has the potential to inform estimation of adverse effects and dosimetry across a broad 

range of questions. EPA also agrees that the modifications to the Clewell (2007) model were peer 

reviewed and found to be sound. The peer review report can be found on EPA’s website at 

http://water.epa.gov/drink/contaminants/unregulated/perchlorate.cfm. However, the major 

reservation expressed was with the use of the model, not the validity of the internal calculations. 

EPA believes that the tabular comparison recommended above is an interesting approach that 

should be considered at such time as sufficient data to conduct a cumulative assessment for 

chemicals affecting the NIS receptor become available. 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 28744 

EPA Comment Code: 2400 

Comment: The NDEP recommends that the EPA incorporate the following key concepts into the 

decision-making process, as explained more fully in the attached comments: 

1. Additional clinical data are needed to help refine the PBPK model. Data are needed for adults, 

including pregnant women, and for neonates concerning thyroidal iodine capacity and the effects of 

sodium-iodide symporter (NIS) upregulation on thyroidal iodine uptake and/or thyroxine levels. 

Also, additional studies of other adults are needed to evaluate the effects of temporary iodine 

deficiency and NIS upregulation on perchlorate competitive inhibition of thyroidal iodine uptake 

and/or free thyroid hormone levels. This additional research would provide useful data to consider 
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in further refining the PBPK model to accurately reflect the effects of iodine deficiency in pregnant 

women, fetuses and neonates. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. EPA plans to continue to evaluate the best available science on 

perchlorate in preparing a proposed maximum contaminant level and goal for perchlorate.

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28798 

EPA Comment Code: 2400 

Comment: REQUEST FOR COMMENTS ON ALTERNATIVE APPROACHES 

a. Using the PBPK model to evaluate the relative sensitivity of life stages to perchlorate exposure in 

drinking water 

NRDC Response: The PBPK model can be used to evaluate life stage sensitivity, and it provides 

evidence that at the proposed HRL of 15 ppb, infants and young children will have a perchlorate 

intake that exceeds the reference dose. 

The EPA scientific staff evaluated the application of the PBPK model, particularly as it applies to 

sensitive life-stages.[FN26: EPA Office of Research and Development. Inhibition of the sodiumiodide symporter by perchlorate: An evaluation of lifestage sensitivity using physiologically-based 

pharmacokinetic (PBPK) modeling. Preliminary Draft. October 2, 2008. EPA/600/R-08/106A. 

Docket ID No. EPA-HQ-OW-2008-0692-0076] On October 2, 2008, EPA issued the staff report 

on this evaluation, which identifies some very troubling findings, including evidence that consuming 

water contaminated at the HRL of 15 ug/L (or ppb) would lead to bottle-fed infants exceeding the 

RfD by 5- fold and young children exceeding the RfD by 2.8-fold, based on average food 

contamination rates, average body weights, and 90th percentile water consumption rates for each 

age group.[FN27: EPA Office of Research and Development. Inhibition of the sodium-iodide 

symporter by perchlorate: An evaluation of lifestage sensitivity using physiologically-based 

pharmacokinetic (PBPK) modeling. Preliminary Draft. Table 4. October 2, 2008. EPA/600/R08/106A. Docket ID No. EPA-HQ-OW-2008- 0692-0076.] Specifically, the PBPK model predicts 

that the RfD is exceeded for infants and children at the originally proposed HRL of 15 ppb, at 90th 

percentile water intake. (See Table 1 below). The table also identifies the magnitude by which the 

RfD is exceeded at EPA's originally proposed HRL of 15 ppb. 

Table 1: Perchlorate intake from water at 15 ppb, with and without food intake, at 90th percentile 

water intake (L/day) [See PDF docket ID EPA-HQ- OW-2009-0297-0412] 

These perchlorate intake values were also reported in the October 10, 2008 FR notice in Table 

8.[FN29: 73 Fed. Reg. at 62078.] Note that the overwhelming majority of perchlorate for these age 

groups comes from water or breast milk, and not from solid food. These data, generated from the 

PBPK model predictions, provide substantial scientific support for the conclusion that infants (both 

breast- and bottle-fed) and young children would exceed the RfD if their dietary water were 

contaminated with perchlorate at the originally proposed HRL of 15 ppb. 
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Despite these conclusions, EPA announced its preliminary determination not to regulate perchlorate 

in drinking water. Although that FR notice did report the staff conclusions, it contradicted them by 

concluding that "EPA believes drinking water with perchlorate concentrations at or below the HRL 

of 15 ug/L is protective of all subpopulations."[FN30: Id. at 60280] EPA failed to provide any data 

to support its conclusion, which is contradicted by the results of PBPK modeling as reported by 

staff experts and in the preliminary determination.[FN31: EPA Office of Research and 

Development. Inhibition of the sodium-iodide symporter by perchlorate: An evaluation of lifestage 

sensitivity using physiologically-based pharmacokinetic (PBPK) modeling. Preliminary Draft. 

October 2, 2008. EPA/600/R-08/106A. Docket ID No. EPA-HQ-OW-2008-0692-0076.] 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. See response to comment code 5220 for a discussion of alternative health 

reference levels. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection (MassDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0495 

EPA Comment ID: 28860 

EPA Comment Code: 2400 

Comment: Section III Alternative Approaches to Analyzing Scientific Data Related to Perchlorate 

in Drinking Water 

For a number of reasons we do not believe that sodium iodide symporter (NIS) inhibition 

predictions based on Physiologically-Based Pharmacokinetic (PBPK) modeling should, at this time, 

be relied upon to establish or justify a perchlorate reference dose (RfD) nor to evaluate relative 

sensitivities between life-stages. Although the PBPK model previously relied upon, but now under 

reconsideration by EPA, provides a valuable exploratory research tool and is a potentially useful 

predictor of perchlorate distribution and NIS effects in the adult, it is highly uncertain regarding the 

fetal and neonatal life-stages of most concern and may not reflect perchlorate effects on thyroid 

function. Our view on this issue is based on the following observations: 

1) In response to peer review comments on the PBPK models, EPA noted that "the models have 

not been specifically parameterized to describe hypothyroid or iodine deficient individuals." In other 

words the model does not take into account responses in those with insufficient iodine intakes, the 

very group of most concern with respect to perchlorate exposures. In other documents EPA has 

also noted that the PBPK model did not account for within group variability in pharmacokinetics; 

uncertainty in several model parameters, including fetal and neonatal values derived from rodent 

models, and differences in adaptive responses. Although peer reviewer comments recommended 

that a much more robust uncertainty analysis be preformed on the model, EPA concluded that this 

was beyond the scope of the current effort and would be difficult to conduct due to data gaps. 

However, such an assessment is critical to determining the ultimate usefulness of the model 

predictions. 

2) The perchlorate associated thyroid hormone alterations reported in Blount et al. 2006 and 

Steinmaus et al. 2007 in women with urinary iodine < 100 ug/L highlight some of these 

uncertainties, as they suggest that either the model estimates of iodide uptake inhibition (IUI) at low 
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perchlorate intake levels are inaccurate; that unexpectedly small increments in IUI may cause thyroid 

effects; and/or that perchlorate may act through additional mechanisms not captured in current 

models. Although NIS inhibition has been viewed as perchlorate's primary mode of action, other 

possible mechanisms that could contribute to its toxicity have been suggested. Based on a 

biologically-based dose response model of the hypothalamus-pituitary-thyroid axis and PBPK 

modeled perchlorate distribution and inhibition of thyroid iodide uptake, a recent assessment 

concluded that IUI was insufficient to explain observed changes in rat thyroid hormone levels 

attributable to perchlorate (McLanahan et al. 2009). These results suggest either that an additional 

mechanism of action exists, perhaps attributable to perchorate uptake into the thyroid and 

interference with other targets involved in hormone synthesis and release or that the PBPK 

modeling is inaccurate. 

3) Although the impact of thyroid toxicants on the fetus can be buffered by the thyroid hormone 

synthesis and reserve capacities of the mother, iodide insufficiency and pregnancy-related stresses on 

maternal thyroid function increase the potential for perchlorate effects during fetal development 

(Glinoer 2001; Ginsberg et al. 2007). These are factors that the PBPK modeling does not adequately 

account for and could lead to a significant underestimate of NIS inhibition. 

4) Available data indicate that neonatal exposures to perchlorate in breast milk are significant. The 

median perchlorate exposure to two week old nursing infants in the U.S. was predicted to be 0.206 

ug/kg/day (95th percentile = 0.744 ug/kg/day) (Ginsberg et al. 2007). Other data indicate that 

nursing infant perchlorate exposures in the U.S. can be even higher. Based on a breast milk intake 

rate of 0.172 L/kg/day and reported median breast milk perchlorate concentrations (Kirk et al. 2005 

and 2007; Pearce et al. 2007a), we estimate that nursing infant perchlorate intakes in three U.S. 

cohorts ranged from 0.56 to 1.57 ug/kg/day. Dasgupta et al. (2008) estimated breast milk 

perchlorate intake rates ranging from 0.3-2.1 ug/kg/day, with intakes of 9 of 13 infants exceeding 

the National Research Council's (NRC) RfD (NRC 2005) (Dasgupta et al. 2008). 

Due to the significance of this exposure pathway, PBPK modeled estimates of perchlorate and 

iodide concentrations in breast milk warrant close scrutiny and additional validation. In response to 

peer review comments, EPA added section 4.1.1 to the May 2009 report, "Inhibition Of The 

Sodium-Iodide Symporter By Perchlorate: An Evaluation Of Life Stage Sensitivity Using 

Physiologically Based Pharmacokinetic (PBPK) Modeling." This section includes several informative 

comparisons of model predictions with published data but no comparison of predicted human 

breast milk perchlorate concentrations with published data. A comparison of breast milk data from 

Pearce et al 2007; Kirk et al 2005 and 2007 etc. combined with estimated US median perchlorate 

intakes (Blount et al 2006) should be completed, as this would provide important insight into model 

uncertainty regarding this critical exposure pathway. 

Response: See response to comment ID 28923 under comment code 2400. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28868 

EPA Comment Code: 2400 
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Comment: COMMENTS IN RESPONSE TO THE EPA NOTICE: ENVIRONMENTAL 

PROTECTION AGENCY [EPA-HQ-OW-2009-0297; FRL-8943-9] RIN 2040-AF08 DRINKING 

WATER: PERCHLORATE SUPPLEMENTAL REQUEST FOR COMMENTS 

Prepared for: PERCHLORATE STUDY GROUP 

October 8, 2009 

Intertox, Inc. 600 Stewart St. Suite 1101 Seattle, WA 98101 206.443.2115 phone 206.443.2117 

facsimile 

 TABLE OF CONTENTS 

EXECUTIVE SUMMARY..............................................................1 I. 

INTRODUCTION................................................................3 II. RESPONSES TO REQUEST FOR 

COMMENTS ON ALTERNATIVE APPROACHES TO ANALYZING SCIENTIFIC DATA 

RELATED TO PERCHLORATE IN DRINKING WATER.............7 III. OTHER 

COMMENTS...........................................................25 IV. 

REFERENCES................................................................36 

 APPENDICES 

APPENDIX A SUPPLEMENTAL TABLES APPENDIX B INITIAL REVIEW OF 

HOPONICK ET AL., 2009 

 LIST OF FIGURES 

FIGURE 1. VISUAL REPRESENTATION OF UF, THE RFD, AND UNACCOUNTED FOR 

CONTRIBUTION OF PERCHLORATE IN FOOD ARE COMPONENTS OF THE POD 

DOSE...20 FIGURE 2. TOTAL GOITROGEN LOAD IN PERCHLORATE EQUIVALENCE * 

BASED ON URINARY MEASUREMENTS FROM WOMEN AGES 12 AND OLDER FROM 

NHANES 2001-2002.**.... 22 FIGURE 3. URINARY REANALYSIS RESULTS OF THE 

NHANES DATA 29 FIGURE 4. PLOTTING OF DATA REPORTED BY DASGUPTA ET 

AL., 2008 TO ILLUSTRATE THE ASSOCIATION BETWEEN CONCENTRATIONS OF 

IODINE AND PERCHLORATE IN URINE AND MILK IN LACTATING WOMEN....32 

EXECUTIVE SUMMARY 

On August 19, 2009, the Environmental Protection Agency (EPA) issued a Federal Register (FR) 

notice requesting comments on alternative approaches to analyzing data related to EPA's 

perchlorate regulatory determination (the Notice; U.S. EPA, 2009b). The Notice says that "these 

additional comments are sought in an effort to ensure consideration of all the potential options for 

evaluating whether there is a meaningful opportunity for human health risk reduction of perchlorate 

through a national primary drinking water rule." 

The following four points summarize the response prepared by Intertox on behalf of the 

Perchlorate Study Group (PSG). 
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1. Interpretation of physiologically-based pharmacokinetic (PBPK) modeling: The use of 

scientifically derived PBPK models is the best scientific approach among all alternatives for 

evaluating the relative sensitivity of different life stages, consistent with the conclusions of EPA's 

peer reviewers and the National Academy of Sciences National Research Council (NRC). The 

current EPA PBPK model for perchlorate, however, uses values for some key parameters (e.g., 

urinary clearance) that are not supported by the scientific evidence. The model also does not account 

for up-regulation of the sodium iodide symporter (NIS). As a result, the model does not provide the 

best scientific estimates of iodide uptake inhibition (IUI) that would be associated with a particular 

perchlorate dose, and likely overestimates IUI from perchlorate exposure for various life stages. 

Further, input parameters are not selected from consistent points within their distributions, such 

that it is unclear whether the model output represents low, average, or upper-bound estimates of 

possible IUI. Nonetheless, the predicted levels of IUI in the Notice are low and would be 

indistinguishable from fluctuations resulting from differences in diet and feeding styles. No adverse 

health concern at any life stage would be expected based on exposure to perchlorate at the point of 

departure dose (7 ug/kg-d). EPA should revise this model to represent science-based accurate 

information on PBPK parameters and use the results to determine whether regulation is necessary. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28880 

EPA Comment Code: 2400 

Comment: A Interpretation of the Physiologically Based Pharmacokinetic (PBPK) Modeling 

Properly conducted, PBPK models provide accurate, peer reviewed scientific information to reduce 

uncertainty about sensitive life stages. PBPK models for perchlorate have been under development 

for a number of years. In its 2005 assessment of perchlorate, the NRC identified several 

subpopulations that are potentially more sensitive than average adults to thyroid effects from 

perchlorate exposure, including pregnant women, fetuses, and infants, based in part on perchlorate 

PBPK models for pregnant and lactating rats and rat pups and adult humans. After the NRC 

evaluation, the perchlorate PBPK model was improved to include pregnant women, the fetus, 

lactating women, and the neonate, and was published in the peer reviewed literature (Merrill et al., 

2005; Clewell et al., 2007). 

Regarding the preliminary regulatory determination for perchlorate, EPA evaluated published PBPK 

models for perchlorate "based on their ability to provide additional information surrounding this 

critical effect for potentially sensitive subgroups and reduce some of the uncertainty regarding the 

relative sensitivities of these subgroups" (U.S. EPA, 2008a). EPA used public comments on the 

preliminary regulatory determination, as well as comments from an external peer review (Eastern 

Research Group, 2008), to further refine the model which is based on both pharmacokinetics and 

pharmacodynamics (U.S. EPA, 2009a) and used it to predict the relative RAIU inhibition for 17 

distinct populations or life stages, including pregnant and lactating women, the fetus, and the 

neonate, assumed to be exposed to 0.007 mg/kg-d in drinking water. The results of this evaluation 

are presented in Table 1 of the Notice. From these results, EPA concluded that "by protecting the 
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fetus of the hypothyroid or iodide-deficient woman from the effects of perchlorate on the thyroid, 

all other life stages and subgroups would be protected." 

EPA requested comments on three general questions regarding its use of the PBPK model as an 

alternative approach to assessing the relative sensitivity of different exposure populations. Responses 

to these questions follow. Note that the responses to Questions 1 and 2 are combined, as the 

questions are not substantively different. 

1. EPA requests comment on using the PBPK model to evaluate the relative sensitivity of the 

various life stages to perchlorate exposure in drinking water. 

2. EPA requests comment on the utility of the PBPK model for predicting the impact of different 

perchlorate drinking water concentrations on sensitive life stages to inform HRL selection. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.EPA does not agree that the model used in the 2008 preliminary 

determination reflects both pharmacokinetics and pharmacodynamics. The model reflects a subset 

of pharmacokinetic parameters for various life stages. Pharmacodynamics is dose description of the 

dose-dependent effect of a chemicals on the target organ. Pharmacodynamics may vary by life stage. 

The model depends upon the current RfD as an expression of the adverse effects of perchlorate, 

and any expression of pharmacodynamic variability is limited to some portion of the 10X 

uncertainty factor for intraspecies variability. The RfD was developed using data from adults, none 

of whom were pregnant. As such, it cannot reflect the potential variability among life stages due to 

pharamacodynamics. Data do not exist to describe the pharmacodynamic variability among life 

stages for perchlorate. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28881 

EPA Comment Code: 2400 

Comment: PBPK modeling is valuable as it can integrate dozens of experimentally derived variables 

drawn from peer reviewed scientific studies to characterize chemical absorption, distribution, 

metabolism, excretion, and toxicity/effect. PBPK modeling is well established in the 

pharmacological and toxicological sciences, where it has been used for more than 80 years to 

understand the action of chemicals in the body. More recently, PBPK models have been used in 

filling scientific gaps in human health data, especially when conducting animal studies is infeasible, 

unethical, or impractical. 

As stated by Mager et al. (2003) in a review of the use of PBPK models: 

The resolution of PK/PD [pharmacokinetic/pharmacodynamic] models and parameters is best 

achieved by having relevant pharmacokinetics..., an understanding of the mechanism of action of the 

drug, appreciating the determinants of any time dependence in responses, and collecting a suitable 

array of experimental measurements as a function of dose and time. When possible, such 

measurements should be sensitive, gradual, quantitative, reproducible, and meaningful. 
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This statement reflects scientific consensus about how scientific information should be used in a 

PBPK model. The EPA PBPK model is for the most part based on this philosophy and can be 

useful for informing risk management decisions. Not all parameters in this model, however, meet 

the criteria required for robust and predictive PBPK modeling. To be useful, the PBPK model 

inputs should be transparent and scientifically based. This would advance the overarching science 

policy articulated by the current EPA Administrator, Hon. Lisa Jackson.[FN8: EPA Administrator 

Lisa Jackson, in her May 9, 2009 memorandum on scientific integrity stated, "While the laws that 

EPA implements leave room for policy judgments, the scientific findings on which these judgments 

are based should be arrived at independently using well-established scientific methods, including 

peer review, to assure rigor, accuracy, and impartiality. This means that policymakers must respect 

the expertise and independence of the Agency's career scientists and independent advisors while 

insisting that the Agency's scientific processes meet the highest standards of rigor, quality, and 

integrity" ( http://www.epa.gov/Administrator/scientificmemo.html)] 

While supportive of a science based PPBK model, an evaluation of the EPA PBPK model reveals 

that model does not produce the best and most scientific estimates of IUI. For example, some 

components of EPA's PBPK model for perchlorate are not supported by the scientific literature and 

result in IUI predictions that do not reflect best scientific estimates of IUI associated with a 

particular perchlorate dose. In particular, EPA's uses values for one of the key parameters in the 

PBPK model, the urinary clearance of perchlorate, that are not supported by the scientific 

literature.[FN9: Per EPA's evaluations, perchlorate PBPK model predictions are highly sensitive to 

urinary clearance rate, such that changes in it significantly impact predicted RAIU inhibition for a 

particular life stage and perchlorate dose. For each of the 17 distinct populations or life stages 

evaluated in the model, EPA used one of two different urinary clearance values: 0.05 L/h-kg for the 

pregnant woman at gestational weeks 13, 20, and 40 (which also impacts the RAIU prediction for 

the fetus at gestational week 40), and 0.13 L/h-kg for all other populations/life stages. If one 

calculates urinary clearance in L/h by multiplying these values by the corresponding scaled body 

weight, the resulting urinary clearance rates for the pregnant woman are much lower than for all 

other adults evaluated by the model: urinary clearance rates range from 1.20 to 1.32 L/h for the 

pregnant woman, 3.21 to 3.28 L/h for the lactating woman, 3.08 L/h for the woman of childbearing age, and 3.15 L/hr for the average adult. The assumption of reduced urinary excretion 

during pregnancy, however, is not supported by the bulk of the scientific literature. The perchlorate 

urinary clearance rates used in the model are based on data collected in Greer et al. (2002). These 

values were originally described in the Merrill et al. (2005) model for adult humans, and were 

incorporated into the Clewell et al. (2003a, 2003b, 2007) models. Per Merrill et al. (2005), the 0.13 

L/h-kg clearance rate is based on the mean "fit" urinary clearance rate for perchlorate for adult 

males and females (nonpregnant) in the Greer et al. (2002) study; the values for the 23 individuals in 

that study ranged from 0.06 to 0.24 L/h-kg. According to Clewell et al. (2007), the 0.05 L/h-kg 

urinary clearance value applied to the pregnant woman (and fetus) was selected from the lower 

bound of this range, in part because this lower value was consistent with data from a study of 

perchlorate-exposed pregnant women in Chile (Tellez et al., 2005). Clewell et al. (2007) describes 

their rationale as follows: In the nonpregnant adult model, Merrill and coauthors (2005a) fitted the 

perchlorate urinary clearance value to each individual for which data were available and noted a 

marked variation between subjects. Values for urinary clearance (ClUcp) ranged from 0.05 to 0.24 

ng/L-h [sic], with an average of 0.13 ng/L-h [sic]. Using the lower bound of these values (0.05 

ng/L) [sic], the gestation model predicted serum levels were within the range of the experimental 

values of Tellez et al. (2005)... Since the lower clearance value lies within the range of the normal 

adult, improves the perchlorate prediction, and yields a more conservative estimate of risk, it was 
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used for all subsequent maternal simulations and dose metric calculations. Note that the actual lower 

bound of the perchlorate urinary clearance range from Greer et al. (2002) (reported in Merrill et al. 

(2005)) is 0.06 L/h-kg, not 0.05 L/h-kg. Further, this value of 0.06 L/h-kg is for an adult male; no 

pregnant women were included in the study population, and the lowest reported value for any 

woman is 0.09 L/h-kg. Clewell et al. (2007) indicated the lower-bound value from Greer et al. (2002) 

is consistent with data collected by Tellez et al. (2005). Tellez et al. (2005) evaluated perchlorate 

exposure in pregnant women in three cities in Chile exposed to perchlorate in water at average 

concentrations ranging from 0.5 to 114 ug/L. This paper says that urinary perchlorate was measured 

during two prenatal visits and one postnatal visit, and reported excretion in units of ug/L and ug/g 

creatinine. Unfortunately, no data are provided in the paper on time course of excretion, so it is 

unclear how Clewell et al. (2007) established that the lower bound of the urinary clearance rate for 

these populations was 0.05 L/h-kg. In selecting a urinary clearance value to use for the pregnant 

woman, EPA considered two additional values: clearance during pregnancy in the average adult 

based on Aboul-Khair et al. (1964); and clearance during pregnancy equal to nonpregnant average 

values. Aboul-Khair et al. (1964) evaluated urinary clearance of iodide in pregnant women in the 

United States and reported that "renal (urinary) clearance for iodide is elevated to as much as two 

times control (nonpregnant) values during pregnancy, and, while clearance then declines fairly 

rapidly towards control after birth, it is still elevated in the first couple of months" (U.S. EPA, 

2009a). EPA assumed that urinary clearance of perchlorate would have the same pregnant to 

nonpregnant ratio reported by Aboul- Khair et al. (1964). EPA ran the model using all three values. 

Of these values, the clearance value used by Clewell et al. (2007) resulted in the highest predicted 

RAIU inhibition. For example, at a dose of 7 ug/kg-d (a dose ten times the RfD of 0.7 mg/kg-d), 

EPA (2009a) reports a RAIU inhibition for the fetus of 11% using the Clewell et al. (2007) clearance 

value, 5.2% using the average non- pregnant adult clearance value, and 3.4% using the Aboul-Khair 

et al. (1964) clearance value. Regarding final selection of this value, EPA (2009a) says: Since there are 

no conclusive human pregnancy data to distinguish which of these alternatives is more likely, EPA 

selected option 1, the lower clearance value reported in the peer-reviewed paper by Clewell et al. 

(2007) for relative response estimation (life stage sensitivity analysis), since this value leads to the 

most sensitive predictions... While this analysis uses the lowest urinary clearance value among the 

alternatives evaluated, it does not provide an overall upper-bound effect estimate because the impact 

of uncertainty and variability in parameters other than those examined here (e.g., uncertainty in 

thyroid NIS parameters and interindividual variability in urinary excretion) was not evaluated. Thus, 

EPA selected a urinary clearance value for this population based on a nonscience consideration that 

lacked corroborating data in the face of other data supporting a higher value. EPA states that 

selection of this value is not meant to reflect uncertainty or a bounded estimate. This is inconsistent 

with the statement in the Notice regarding the use of conservatism in the model (U.S. EPA, 2009a), 

that: The PBPK model for each life stage is presumed to represent a typical or average individual 

from that life stage. Thus, in evaluating specific PBPK parameter choices, especially for urinary 

clearance, EPA's objective was to ensure that the values appropriately represented an average or 

central value for a given life stage and age. EPA further elaborates (U.S. EPA, 2009a): In the case 

where more than one alternative clearance value appeared to be equally likely (i.e., had a similar 

quality and amount of supporting data), then the more "sensitive" option was selected (i.e., the 

option that leads to predictions of the highest sensitivity to perchlorate- induced RAIU). The overall 

analysis did not seek to select parameters associated with highest predicted effect and is not intended 

to represent an upper-bound estimate of the average effect of perchlorate in these populations. 

Modeling choices are assumed to represent the best or most likely (central) estimate for an average 

individual within the population. There is uncertainty about the average, and EPA has selected from 

within the range of uncertainty, but there is still expected to be population variability around the 
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model predictions based on that choice, with the model prediction being near the center of the 

distribution. The Notice states that the urinary clearance value was selected to "represent the best or 

most likely (central) estimate for an average individual within the population." Selecting the lowest 

urinary excretion value-one that produces the highest estimate of RAIU inhibition-is not the 

"average." The Notice declares that all three clearance values considered had a similar quality and 

amount of supporting data; in fact, this cannot be true based on the information presented. The 0.05 

L/h-kg value was of low scientific quality (it is not supported by either source EPA cites as its 

primary basis, i.e., Greer et al. (2002) or Tellez et al. (2005)) and higher values are better supported 

by the scientific literature, as discussed below. The scientific literature shows that, although minimal, 

data are available on perchlorate urinary clearance or excretion rates during pregnancy, but do not 

suggest lower excretion of perchlorate during pregnancy. In the study of Chilean women, Tellez et 

al. (2005) reported higher urinary perchlorate excretion (measured as ug/g creatinine) during 

pregnancy relative to postpartum for women in two of the three cities evaluated (Chanaral and 

Taltal, which had mean concentrations of perchlorate in tap water of 5.8 and 114 ug/L). In the "low 

perchlorate" city (Antofagasta, with a mean tap water concentration of 0.5 ug/L), excretion was 

somewhat higher postpartum. Based on urine samples collected during the NHANES 2001-2002 

study, Blount et al. (2007) reported higher urinary perchlorate in pregnant women (mean 3.27 ug/g 

creatinine, n = 115), relative to all women of reproductive age (mean 2.97 ug/g creatinine, n = 662). 

Interpretation of data on urinary clearance or excretion of iodide is complicated by the iodide status 

of populations; however, Smyth et al. (1997) reported that in an area of moderate iodine intake 

(median urinary iodide 82 ug/g creatinine), urinary iodide excretion was increased during all three 

trimesters of pregnancy relative to nonpregnant controls. EPA's selection of the lowest identified 

urinary clearance value for the pregnant woman and fetus is inconsistent with the statement in the 

Notice about the Agency's use of conservatism in the model (U.S. EPA, 2009a): The PBPK model 

for each life stage is presumed to represent a typical or average individual from that life stage. Thus, 

in evaluating specific PBPK parameter choices, especially for urinary clearance, EPA's objective was 

to ensure that the values appropriately represented an average or central value for a given life stage 

and age. EPA further states, "there is still expected to be population variability around the model 

predictions based on that choice, with the model prediction being near the center of the 

distribution," and: While this analysis uses the lowest urinary clearance value among the alternatives 

evaluated, it does not provide an overall upper-bound effect estimate because the impact of 

uncertainty and variability in parameters other than those examined here (e.g., uncertainty in thyroid 

NIS parameters and interindividual variability in urinary excretion) was not evaluated. Nonetheless, 

in practice, selection of the lowest urinary clearance value for two of the subpopulations renders the 

RAIU inhibition predictions for these populations more conservative than for other populations, 

making application of model results to risk assessment difficult to interpret from a purely scientific 

basis.] 

In addition to using the best science to support PBPK values, other parameters could be added, 

such as up-regulation of the NIS. Up-regulation of the NIS represents an adaptive response to 

iodine deficiency in the thyroid, but EPA (2009b) did not incorporate a mechanism of up-regulation 

in the EPA model. Incorporation of NIS regulation into the model would more accurately reflect 

the probable response to perchlorate exposure in the environment.[FN10: Over the past decade, 

research regarding thyroid autoregulation and the regulation of expression of the NIS has 

proliferated. Evidence suggests that the NIS is up- regulated in response to iodine deficiency in the 

thyroid. Up-regulation of the NIS causes the number of NIS membrane proteins to increase; thus, 

when an individual is iodine deficient, the body increases the number of NIS "pumps" such that the 

thyroid is more effective at capturing iodide. This is a common adaptive mechanism that many 
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tissues, including the thyroid gland, use to maintain hormone homeostasis. The Draft EPA Office of 

the Inspector General (OIG) report (U.S. EPA 2008b) appears to consider up-regulation of NIS 

expression as well. Earlier versions of the model using the rat did consider up- regulation, and 

showed no RAIU inhibition in the rat thyroid after 18 days of exposure at perchlorate doses up to 

10 mg/kg-d (350,000 ppb assuming default body weight and water intake) (Clewell et al., 2003a). 

Up-regulation was not included in the human model, "based on the fact that upregulation was not 

seen in the nonpregnant adult after 2 wk of doses as high as 1 mg ClO4- (Merrill et al., 2005)" and 

although "the current simulations cover lifetime exposures rather than a few weeks, the 

accompanying data on thyroid hormones (TSH, T4) still do not show evidence of thyroidal upregulation (Crump et al., 2000; Tellez et al., 2005)" (Clewell et al., 2007). The NRC report, however, 

acknowledges the up- regulation of NIS expression, but did not incorporate it into their risk 

assessment. NRC (2005) states: ...rats compensated for the inhibition within 5 days of perchlorate 

administration, most likely by increasing the expression of NIS in the thyroid. The data suggest that 

compensation occurs more quickly in rats because rats have a smaller reserve capacity of thyroid 

hormones than humans. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28883 

EPA Comment Code: 2400 

Comment: Parameters used in the PBPK model were selected from inconsistent points within their 

distributions. For example, as described above, EPA (2009a) selected a lower bound value to 

describe the urinary clearance of perchlorate for the pregnant woman and fetus. In contrast, EPA 

reports that the urinary clearance values it selected for all other population subgroups fall in the 

middle of the range of possible values (U.S. EPA, 2009a). As a result, it is difficult to interpret the 

model output because it is unclear whether the output represents lower-, middle-, or upper- bound 

predictions of possible IUI caused by perchlorate exposure."[FN11: When conducting calculations 

to reflect exposure within a population, each parameter can have a range of possible values. In order 

for PBPK model output to be meaningful, the basis for selection of specific values within the range 

of possible values should be described and the relationship to the overall distribution for that 

parameter should be characterized (e.g., lower-bound, average, median, upper-bound). Further, in 

the absence of probabilistic assessment, if point estimates are selected for incorporation in the 

model, a consistent rationale should be applied in choosing values for the various parameters so that 

the location of the output within the overall distribution can be approximated. For example, when 

conducting baseline human health risk assessments for a reasonable maximum exposure (RME) 

scenario, EPA recommends estimating "a conservative exposure case (i.e., well above the average 

case) that is still within the range of possible exposures," and intake variable values for a given 

pathway should be selected so that the combination of all intake variables results in an estimate of 

the reasonable maximum exposure for that pathway (U.S. EPA, 1998a). The objective of evaluating 

conservative exposures is to generate an upper-bound estimate of exposure below which adverse 

health effects are unlikely. Note that although EPA presents the impact of alternative urinary 

clearance assumptions on model-predicted RAIU inhibition in its discussion document on the 

PBPK model (Table 4-2, U.S. EPA, 2009a), it does not present this information in the Notice.] 
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Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28902 

EPA Comment Code: 2400 

Comment: IV. CONCLUSIONS 

1. The use of scientifically derived PBPK models represents the best scientific approach for 

evaluating the relative sensitivity of different life stages and to compare to occurrence data. As 

constructed, however, the perchlorate PBPK model likely overestimates IUI from perchlorate 

exposures for various life stages. Only when the best available science is shared in a transparent 

process can the public be empowered to assist the Agency in achieving the best public health 

decisions. Nonetheless, the predicted levels of IUI in the Notice are very low and would be 

indistinguishable from fluctuations resulting from differences in diet and feeding styles. No adverse 

health concern at any life stage would be expected based on exposure to perchlorate at the POD 

dose (7 ug/kg-d). 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0527 

EPA Comment ID: 28909 

EPA Comment Code: 2400 

Comment: Specific issues on which USEPA requests comments in its August 18, 2009 notice are 

discussed below: 

Interpretation and Application of Physiologically-based Pharmacokinetic (PBPK) Modeling 

In the October 10, 2008 notice, the PBPK model was used to evaluate the effects of the proposed 

HRL, 15 ug/L, on the perchlorate dose reaching the thyroid and to estimate effects on the inhibition 

of thyroidal iodine uptake in sensitive subpopulations. It was assumed that the fetus of the pregnant 

woman was the most susceptible subpopulation, and our primary concern was that the exposure and 

health risks of bottle fed and breast fed infants and older children, as predicted by the PBPK model, 

were ignored. 

Using 90th percentile water intakes, the PBPK model predicts that when water with 15 ug/L 

perchlorate is used to prepare formula, 7-day and 60-day old bottle-fed infants are exposed to more 

than 5 times the RfD, and that iodide uptake in 7-day old infants is decreased by 2.2% (Table 4-5). 

Exposures of 7-day and 60- day breast-fed infants and children 6-12 months and 1-2 years are also 

predicted to exceed the Reference Dose. Even if the model was to use the median rather than the 
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90th percentile water intake, the RfD would be greatly exceeded for bottle-fed infants. We 

recommend that USEPA consider the PBPK model's predictions of exposures and effects in these 

sensitive infants and children, as well as the exposure of the fetus through the pregnant mother, in 

evaluating the potential for perchlorate in drinking water to inhibit thyroidal iodine uptake. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. See response to comment code 5220 for a discussion of 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0527 

EPA Comment ID: 28910 

EPA Comment Code: 2400 

Comment: However, there are several concerns that indicate the need for caution in using the 

PBPK model to determine a health-protective drinking water concentration for perchlorate. First, it 

is based on average weight babies and average weight healthy adults, including pregnant women. 

Furthermore, due to lack of availability of the needed data, only 40-week fetuses were considered 

and it was not possible to model effects on fetuses at earlier stages of development. Thus, the PBPK 

model may not adequately predict the effects of perchlorate on those who are particularly 

susceptible to its effects, such as low birth weight infants, mothers or infants with iodine deficiency 

or hypothyroidism, and fetuses younger than 40 weeks. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination. 

Commenter Name: Danielle Blacet 

Commenter Organization: Association of California Water Agencies 

EPA Document ID: EPA-HQ-OW-2009-0297-0208 

EPA Comment ID: 28923 

EPA Comment Code: 2400 

Comment: Response to questions posed by USEPA: 

1) PBPK Modeling (page 41886) 

ACWA does not take issue with this type of pharmacokinetic modeling. However, in previous 

regulatory determinations and drinking water standards, pharmacokinetic models were only used in a 

secondary fashion, if at all, after the toxic end point was identified by the relevant epidemiological 

data. We would like clarification on the justification for modifying existing procedures. 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group (EWG) 

EPA Document ID: EPA-HQ-OW-2009-0297-0499 

EPA Comment ID: 28930 
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EPA Comment Code: 2400 

Comment: In this notice, the Agency specifically requests comments on certain approaches within 

their assessment, including the following: 

1) Use of PBPK modeling analysis to inform the regulatory determination for perchlorate 

2) Appropriateness of alternative health reference levels (HRLs) described in the notice to address 

and account for risk to all potentially sensitive life stages 

3) Occurrence analysis including use of Bayesian model and U.S. Census data 

Use of PBPK model: EWG supports the use of the PBPK model to estimate the extent of iodine 

uptake inhibition in sensitive life stages only if significant limitations of the current model are 

addressed. 

In this notice, one of the approaches that the Agency considers is the following: "... use the PBPK 

modeling analysis to explore the relative sensitivity of the various life stages of concern to a fixed 

dose such as the point of departure (POD) or the reference dose (RfD)." In this case, the agency 

notes that the "POD is the lowest dose administered in the Greer et al clinical study...". 

The Greer study included only 37 study participants who were divided into several study groups and 

administered different doses of perchlorate for 14 days (Greer et al 2002). The researchers 

determined that a daily perchlorate dose of 0.007 mg/kg/day was the no observed effect level 

(NOEL); the results from this study were used by the National Academy of Sciences (NAS) in 

setting the reference dose (RfD) for perchlorate of 0.7 ug/kg/day. 

The Greer study results and assumptions drawn from them have been questioned in a peer-reviewed 

article that was published in Environmental Health Perspectives in 2005 (Ginsberg and Rice 2005). 

Two toxicologists, one from the Connecticut Department of Public Health and the other from the 

Maine Bureau of Health, conducted an analysis of the raw data from the Greer study and concluded 

the following: "Individual results of Greer et al. point to an effect in four of the seven individuals 

tested at the lowest dose (0.007 mg/kg/day), indicating that this dose is an effect level." In other 

words, while Greer et al. and the NAS both concluded that 0.007 mg/kg/day is a no observed effect 

level (NOEL), closer analysis of the data reveals that four of the seven study subjects in this group 

experienced effects at this dose, thereby invalidating 0.007 mg/kg/day as a NOEL. 

The Massachusetts Department of Environmental Protection (Mass DEP), which has set the most 

stringent drinking water standard for perchlorate nationally, had the following observations about 

the Greer study: 

"MassDEP has concerns about the lowest dose in the Greer study being a no-effect level based on 

the facts that: due to the small number of subjects in the lowest dose group, there is low power to 

detect a statistically significant effect; averaging of group responses obscures positive individual 

inhibition; a non- statistically significant IUI (iodine uptake inhibition) effect was observed at the 

lowest dose tested; and, good low dose corroborating data is lacking" (MassDEP 2006). 
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In light of these valid criticisms of the Greer study, it is clear that any exposure modeling based on 

the results of this study, including the agency's current proposal to use PBPK modeling with a POD 

derived from this particular study, would not be accurate. The PBPK model also does not address 

iodine status, an important factor in determining vulnerability to perchlorate (Blount et al 2006b). 

Response: See response to comment code 2100 for a discussion of the Reference Dose for 

perchlorate. See response to comment code 2300 for a discussion of EPA’s use of the PBPK 

models. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 29101 

EPA Comment Code: 2400 

Comment: EPA failed to provide any data to support its conclusion, and is contradicted by the 

results of PBPK modeling as reported by staff experts and in the Federal Register notice.[FN53: 

EPA Office of Research and Development. Inhibition of the sodium-iodide symporter by 

perchlorate: An evaluation of lifestage sensitivity using physiologically-based pharmacokinetic 

(PBPK) modeling. Preliminary Draft. October 2, 2008. EPA/600/R-08/106A. Docket ID No. 

EPA-HQ-OW-2008-0692-0076.] 

Response: See response to comment code 2300 for a discussion of PBPK modeling in this 

regulatory determination.
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EPA Comment Code: 2410 Use of PBPK model to select life-stage-specific 

HRLs 

Individual Comments 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0653 

EPA Comment ID: 28558 

EPA Comment Code: 2410 

Comment: The Agency showed additional conservatism from the NRC recommendation in 

adjusting the preliminary guidance for perchlorate to 15 ppb in water in order to account for the 

relative source contributions of drinking water and dietary sources in order to protect pregnant 

women and their fetuses. This level, as demonstrated by the physiologically-based pharmokinetic 

(PBPK) modeling, is likewise protective of other potentially sensitive lifestages. The PBPK modeling 

for infants and young children do not exceed the 10x (i.e. ten fold) intraspecies factor set from the 

adult values thereby showing that the 10x intraspecies factor is protective and provides no 

justification for increasing an uncertainty factor for perchlorate beyond the default (i.e. ten fold or 

10x). For this reason, EPA has no basis for adjusting the reference dose (RfD) of 0.0007 

mg/kg/day, or the methodology for setting the HAL based on a 70 kg adult consuming two (2) 

liters of water. This traditional method, used previously by EPA with SDWA contaminants is 

sufficiently conservative as the level of water consumed (two liters) is the 99th percentile estimate, 

and, this RfD is based on a no-effect level (NOEL) from the Greer et. al. 2002 study rather than a 

no adverse effect level (NOAEL). 

Response: EPA does not agree that allowance for contributions of perchlorate from sources other 

than drinking water introduces additional conservatism. Rather, allowance for other sources of 

perchlorate permits EPA to establish a concentration of perchlorate in drinking water that maintains 

a tolerable risk level without adjusting the existing background. 

The modeled estimates of exposure to various life stages, presented as alternative HRLs in the 

August 2009 supplemental request for comments, indicate values as much as seven times that for 

pregnant females. However, the life stage variability in the model estimates reflects pharmacokinetics 

only. Pharmacodynamic variability is not reflected nor can it be estimated using the modified Clewell 

(2007) model. Data permitting estimation of pharmodynamic variability among life stages is not 

available. Therefore, it is not possible to determine whether the alternative HRLs are within the 

variability reflected in the RfD. EPA will continue to evaluate the significance of varying exposure 

estimates as the Agency develops a NPDWR for perchlorate. 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 28750 

EPA Comment Code: 2410 
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Comment: b. EPA requests comment on the utility of the PBPK model for predicting the impact 

of different perchlorate drinking water concentrations on sensitive life stages to inform HRL 

selection. 

Comment A.4.b.1: Additional refinement and supporting rationale for the current configuration of 

the PBPK model is needed based on actual human study observations to enable EPA to use this 

model for the stated purpose. This refinement should include an evaluation of the potential for 

sustained FT3 and/or FT4 reductions in humans including pregnant women, fetuses, and neonates. 

Human data (likely including reproductive age females and adolescents) on the pharmacokinetic use 

of perchlorate for lowering thyroxine levels in hyperthyroid patients are available in both published 

reports and likely also in clinical trials and unpublished data from various research groups. A critical 

step to support use of the PBPK model should include development of a quantitative term that 

defines the relationship between steady state blood perchlorate and the decrement in free and total 

thyroid hormones in reproductive age females. Much of the data needed for this refinement and 

supporting rationale are not currently available. Consequently, the EPA should send out queries 

searching for available unpublished human datasets relevant to the modeling evaluation, and 

encourage the development of appropriate studies to acquire these data and permit support for and 

use of the PBPK model. 

One example of technical difficulties in the model is the consideration of iodine deficiency and 

associated NIS upregulation in the pregnant mother, fetus, and neonate. Additional clinical data are 

needed for adults (including pregnant women, and in neonates) concerning thyroidal iodine capacity 

and the impact of NIS upregulation on thyroidal iodine uptake and/or thyroxine levels. Also, 

additional studies of other adults are needed to evaluate the effects of temporary iodine deficiency 

and NIS upregulation on perchlorate competitive inhibition of thyroidal iodine uptake and/or free 

thyroid hormone levels. This additional research would provide useful data to consider in further 

refining the PBPK model to accurately reflect the effects of iodine deficiency in pregnant women, 

fetuses and neonates. 

Response: See response to comment ID 28800 under comment code 2410. 

EPA agrees that the PBPK model used in preparation of the 2008 Preliminary Regulatory 

Determination requires further refinement before it can be used to develop an HRL. EPA also 

agrees that the data required to permit the necessary modifications does not exist at this time. As 

additional data become available, EPA will be able to determine whether further effort to develop a 

PBPK model for different life stages exposed to perchlorate is warranted. The attributes and 

components of that model cannot be determined at this time.

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28800 

EPA Comment Code: 2410 

Comment: b. Utility of the PBPK model for predicting the impact of different perchlorate drinking 

water concentrations on sensitive life stages to inform the HRL 

NRDC Response: The PBPK model can predict the impacts of perchlorate water contamination on 

different life stages; it predicts that sensitive populations are not protected by the proposed HRL 
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As detailed in our response above, the EPA staff report issued on October 2, 2008, describes 

findings from the PBPK model that consuming water that was contaminated at the HRL of 15 ug/L 

would lead to bottle-fed infants exceeding the reference dose by 5- fold and young children 

exceeding the reference dose by 2.8-fold, based on average food contamination rates, average body 

weights, and 90th percentile water consumption rates for each age group.[FN33: EPA Office of 

Research and Development. Inhibition of the sodium-iodide symporter by perchlorate: An 

evaluation of lifestage sensitivity using physiologically-based pharmacokinetic (PBPK) modeling. 

Preliminary Draft. October 2, 2008. Table 4. EPA/600/R-08/106A. Docket ID No. EPA-HQ-OW2008- 0692-0076.] 

These findings from the PBPK model analysis are supported by other published studies. A related 

study estimated perchlorate doses that correspond to urinary perchlorate excretion (hereinafter 

referred to as "Blount (2007)").[FN34: Blount BC, Valentin-Blasini L, Osterloh JD, Mauldin JP, 

Pirkle JL. Perchlorate exposure of the US Population, 2001-2002. J Expo Sci Environ Epidemiol. 

2007 Jul;17(4):400-7. Epub 2006 Oct 18.] Calculating doses based on urinary excretion is feasible 

because perchlorate is not metabolized and has a short half- life of approximately 8 hours.[FN35: 

Ibid.] Blount (2007) showed that the adjusted geometric mean for perchlorate exposure in women 

was 0.059 ug/kg-day, and the 95th percentile exposure was 0.215 ug/kg-day. This means that the 

adverse effects of decreased serum T4 and increased TSH in women with low dietary iodide (that is, 

urinary iodide below 100 ug/L) described by Blount (2006) are occurring at perchlorate exposures 

below the RfD of 0.7 ug/kg- day.[FN36: Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, 

Caldwell KL. Urinary perchlorate and thyroid hormone levels in adolescent and adult men and 

women living in the United States. Environ Health Perspect. 2006 Dec;114(12):1865-71.] As such, 

the proposed HRL of 15 ppb will not protect sensitive subpopulations. 

An extensive literature review and health assessment by Ginsburg et al.[FN37: GL Ginsburg, DB 

Hattis, RT Zoeller, and DC Rice. 2007. Evaluation of the U.S. EPA/OSWER preliminary 

remediation goal for perchlorate in groundwater: Focus on exposure to nursing infants. Environ 

Health Perspect. 115(3):361-369. http://www.ehponline.org/members/2006/9533/9533.html] 

published since the NRC review found that "drinking-water perchlorate must be < 6.9 ug/L to keep 

the median, and < 1.3 ug/L to keep the 90th-percentile nursing infant exposure below the 

RfD."[FN38: GL Ginsburg, DB Hattis, RT Zoeller, and DC Rice. 2007. Evaluation of the U.S. 

EPA/OSWER preliminary remediation goal for perchlorate in groundwater: Focus on exposure to 

nursing infants. Environ Health Perspect. 115(3):361-369.] Based on both exposure and toxicity 

information, and data on sensitive populations, the proposed HRL of 15 ppb, which is more than 

twice as high as the limit proposed by Ginsberg et al, will leave significant portions of the population 

at risk. 

Response: EPA agrees that reassessing exposure assumptions and other life stages warrants further 

consideration. 

EPA also considered applying the model directly to the exposures of other sensitive life stages to 

develop HRLs for these life stages. The NRC (2005) identified “the fetuses of pregnant women who 

might have hypothyroidism or iodide deficiency” as “the most sensitive population,” but also 

identified infants and developing children as additional “sensitive populations.” EPA derived 

potential alternative HRLs for 14 different life stages as presented in the supplemental request for 

comments (EPA 2009). Alternative HRLs are estimates of the maximum concentration of 

perchlorate that can be consumed in drinking water without an individual’s total perchlorate dose 
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from food and water exceeding the RfD. EPA agrees that exposures reported in the literature 

suggest some life stages may be exposed to quantities of perchlorate above the RfD. 

National Research Council (NRC). 2005. Health Implications of Perchlorate Ingestion. National 

Academies Press, Board on Environmental Studies and Toxicology, January, 2005, Washington, 

D.C. 276pp. 
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EPA Comment Code: 2420 Suggestions for alternative ways to use the PBPK 

model to inform the regulatory determination 

Individual Comments 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 28751 

EPA Comment Code: 2420 

Comment: c. EPA requests suggestions for ways to use the PBPK modeling analysis to inform the 

regulatory determination for perchlorate that are different from those described in this notice or the 

October 10, 2008 notice. 

Comment A.4.c.1: Prior to use of the PBPK model as a part of the regulatory determination, the 

range and primary sources of uncertainty in the model output should be evaluated and described. 

Once properly validated and supported, the model may be used to evaluate a number of 

physiological and pharmacokinetic impacts of perchlorate competitive inhibition, including 

alternative approaches of basing the reference dose on clinically important changes in thyroidal 

iodine uptake and/or thyroxine levels. 

Response: The modified Clewell (2007) model was subjected to peer review by the Office of 

Research and Development, EPA. However, EPA agrees that additional modification and 

refinement of the model is needed before it can be used to develop an HRL to determine the need 

to establish an NPDWR. The extent and nature of modifications and refinements needed are not 

clear at this time. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28801 

EPA Comment Code: 2420 

Comment: c. Using the PBPK modeling analysis to inform the regulatory determination for 

perchlorate that is different from those described in the October, 2008 FR notice 

NRDC response: The PBPK model may be used to derive a science-based adjustment factor; the 

model support an adjustment factor of at least 15-fold to inform the regulatory determination for 

perchlorate. 

EPA normally uses a 10-fold default uncertainty factor to adjust for variations among individuals, 

called the intraspecies factor, when the Agency lacks adequate data to calculate variability between 

individuals. EPA used this 10- fold intraspecies factor for its perchlorate hazard assessment on its 

IRIS database: "An intraspecies uncertainty factor of 10 is applied to protect the most sensitive 

population, the fetuses of pregnant women who might have hypothyroidism or iodide 
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deficiency."[FN39: EPA. IRIS database. Perchlorate and perchlorate salts. 

http://www.epa.gov/ncea/iris/subst/1007.htm#revhis] The Agency has adopted the practice of 

describing the default 10-fold intraspecies factor as being comprised of the product of two 3-fold 

factors, one for harmacokinetic variability, and the other for pharmacodynamic variability.[FN40: US 

EPA. Office of the Science Advisor: Staff Paper, Risk Assessment Principles & Practices. Page 69, 

Section 4.3.2. EPA/100-B-04/001. March, 2004. http://www.epa.gov/osa/pdfs/ratf-final.pdf] 

Pharmacokinetics describes the way that a compound such as perchlorate moves through the body, 

including its absorption, distribution, metabolism and excretion. In contrast, pharmacodynamics 

describes what the compound does in the body, including depressing, stimulating, irritating, or 

killing cells or systems. 

According to the IRIS glossary of terms, a physiologically based pharmacokinetic (PBPK) model 

estimates the dose of a compound to a target organ or tissue by calculating the rate of absorption in 

the body, the distribution among target organs, the metabolism of the compound, and the excretion 

of the compound.[FN41: IRIS Glossary. Physiologically Based Pharmacokinetic (PBPK) Model. 

http://www.epa.gov/ncea/iris/help_gloss.htm#p] In other words, the PBPK model, by definition 

and design, estimates the pharmacokinetics of a compound. 

The data from EPA's staff report shows that EPA's reliance on a default uncertainty factor of 10 

underestimates the variability between fetuses and adults. The Executive Summary of the staff 

report states that "at a perchlorate dose of 7 ug/kg-day, the percent RAIU inhibition predicted by 

the model for the near-term fetus is 5-fold greater than the average adult....The same analysis 

predicts percent RAIU inhibition approximately 1-2 fold higher for the breast- fed and bottle-fed 

infant (7-60 days) than for the average adult."[FN42: See EPA Staff Paper, Executive Summary, p. 4 

and Table 3; see also 73 Fed. Reg. 60278.] More specifically, for perchlorate, the variability between 

a near-term fetus (40 weeks gestation) and an adult is 5.3-fold. Therefore, the PBPK model supports 

a pharmacokinetic adjustment factor of at least 5-fold. 

The Agency has no information from the PBPK model, or from other data, to develop an 

intraspecies uncertainty factor for pharmacodynamic variability, particularly between adults and 

sensitive lifestages. Therefore, EPA should retain a factor of at least 3-fold or more to adjust for 

pharmacodynamic uncertainty, consistent with its current practice. 

To be consistent with EPA policy and practice, EPA should use a total intraspecies uncertainty 

factor of 15-fold, rather than 10 fold. Based on the data from the PBPK model to support a 

pharmacokinetic intraspecies variability factor of 5, and the lack of pharmacodynamic data to 

support a default factor of 3, the use of a 15-fold uncertainty factor is supported by the available 

data. 

Response: EPA agrees that the modeled estimates of alternative HRLs reflect only 

pharmacokinetics and do not consider uncertainty due to pharmacodynamics. EPA’s RfDs typically 

factor in both, with a standard apportionment of 3.16 for each. EPA does not believe that it is 

possible to determine whether a 10-fold uncertainty factor is sufficient to reflect both 

pharmacokinetics and pharmacodynamics. However, EPA acknowledges that 10X may be 

insufficient. Data do not currently exist to provide an estimate of the pharmacodynamic component 

of the intraspecies uncertainty factor. 

Commenter Name: 
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Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28884 

EPA Comment Code: 2420 

Comment: 3. EPA requests suggestions for ways to use the PBPK modeling analysis to inform the 

regulatory determination for perchlorate that are different from those described in this notice or the 

October 10, 2008 notice. 

The PBPK model can provide useful information to characterize the relative sensitivity of this life 

stage if model parameters are scientifically defensible and selected from comparable points within 

their parameter distributions, and if nonscientific considerations do not introduce unexplained bias 

into the selection of parameter values. To be most useful, EPA should use probabilistic methods to 

characterize the uncertainty and variability around parameter distributions and the range and 

likelihood associated with model-predicted RAIU inhibition for each population or life stage. Use of 

probabilistic methods is consistent with the Agency's current recommendations for use of 

probabilistic methods in risk assessment to help inform risk management decisions.[FN12: 

http://www.epa.gov/fedrgstr/EPA-RESEARCH/2009/August/Day-18/r19755.htm; 

http://vvww.epa.gov/raf/prawhitepaper/pdf/pra_mgr_summary_0609.pdf.] 

Additional considerations would provide perspective on the significance of the IUI associated with 

low dose perchlorate exposure. For example, EPA should present the change in RAIU inhibition 

when the RfD is modeled rather than the Greer et al. (2002) POD, which is ten fold higher. 

Response: EPA believes that the modified Clewell (2007) model is useful in examining which life 

stages are most susceptible to the effects of perchlorate. For example, the model indicates that a 

fetus may be seven times more sensitive to the effects of perchlorate than a pregnant woman. The 

model also allows for the estimation of the concentration of perchlorate in breast milk (thus breastfed infant exposure) at various maternal perchlorate exposure levels. Data do not exist at this time to 

permit a more expansive development of the model for various life stages. 

EPA believes that the RfD derived by the NRC using the Greer et al. (2002) remains the appropriate 

estimate of health effects due to perchlorate for use in assessment of risk. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28885 

EPA Comment Code: 2420 

Comment: Also, multiple chemical agents affect the uptake of iodide into the thyroid in the same 

way as perchlorate. These goitrogens, which include thiocyanate and nitrate, can be found naturally 

in common foods, including produce, milk, and cured meats. Incorporation of thiocyanate and 

nitrate exposure into the PBPK model should provide useful information on the relative IUI caused 

by exposure to these agents and to perchlorate. Thus, daily diets for children and adults including 

these foods are predicted to have a greater effect on IUI than would result from drinking two liters 

of water containing perchlorate at environmentally relevant levels (e g., estimated perchlorate 

drinking water equivalent concentrations associated with the thiocyanate and nitrate present in these 
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diets are estimated to be at least 1,500 to 29,000 ppb). Based on these data, the contribution of 

perchlorate in drinking water at a concentration of 20 ppb (assuming consumption of 2 liters per 

day) to total daily IUI associated with a typical diet would be a fraction of these values. 

Response: EPA does not disagree that a total iodine inhibitor load, including naturally-occurring 

NIS inhibitors, should be considered. However, adequate data do not exist at this time to 

characterize adequately the relative affinity of various iodide uptake inhibitors for the NIS receptor. 

In addition, no data exist to characterize their relative potency in impacting thyroid hormone levels. 

Given this lack of data, EPA believes that it is prudent to consider the potential adverse health 

effects for perchlorate independently until data are developed to permit consideration of multiple 

goitrogens jointly. 
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EPA Comment Code: 2500 Other health effects studies, models, and data for 

EPA to consider (besides NAS/NRC report, NHANES biomonitoring data, 

and PBPK models already evaluated) 

Individual Comments 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0648 

EPA Comment ID: 19991 

EPA Comment Code: 2500 

Comment: According to the office of environmental health hazard assessment, see link: 

http://www.oehha.ca.gov/public_info/facts/faqperchlorate.html, perchlorate has not been 

scientfically proven to cause cancer in humans at the doses likely to be in drinking water. The 

University of California conducted 3 separate studies on the topic. 

Response: EPA respectfully disagrees with this comment. In 2003, the National Research Council 

(NRC) of the National Academy of Sciences (NAS) was asked by EPA to assess the current state of 

the sciences regarding potential adverse effects of perchlorate exposure and to determine whether 

EPA’s prior perchlorate risk assessment findings were consistent with current scientific evidence. In 

a NRC 2005 review (“Health Implications of Perchlorate Ingestion”, (NRC, 2005)), the NRC 

recommended that data from the Greer et al. (2002) human clinical study be used as the basis for 

deriving a perchlorate reference dose (RfD) (NRC, 2005). From this Greer et al. (2002) human 

clinical study, the statistical no observed effect level (NOEL) for the perchlorate-induced inhibition 

of thyroid iodide uptake was determined to be 7.0 ug/kg, which corresponded to an iodide uptake 

inhibition of 1.8 %. The NRC concluded that the most health protective and scientifically valid 

approach to deriving a reference dose for perchlorate was to base the perchlorate RfD on the 

inhibition of iodide uptake by the thyroid, and that iodide uptake inhibition, though not an adverse 

effect per se, is the most appropriate precursor event, and would precede any more severe adverse 

health effects of perchlorate exposure in humans. The NRC recommended basing the RfD on a 

precursor to an adverse effect rather than an adverse effect, per se. The precursor event precedes a 

downstream adverse effect in the dose response continuum. In this case, NRC used prevention of 

iodide uptake inhibition, a precursor to adverse thyroid effects, to establish a level at which no 

adverse effects would be anticipated in exposed populations. This approach is consistent with the 

Agency’s policy on the use of precursor events when appropriate in establishing the critical effect 

upon which an RfD is based (U.S. EPA, 2002). The NRC recommended that EPA apply an 

uncertainty factor of 10 to this NOEL of 7.0 ug/kg for the perchlorate-induced inhibition of thyroid 

iodide uptake, to account for differences in sensitivity between healthy adults and the most sensitive 

sub-population, consisting of fetuses of pregnant women who might have hypothyroidism or iodide 

deficiency. Iodide uptake inhibition has been identified in the literature as an area of concern in 

connection with increasing the risk of neurodevelopmental impairment in fetuses of high-risk 

mothers. The NRC viewed the recommended uncertainty factor of 10 as conservative and protective 

of health, given that the NOEL is based on a non-adverse effect (iodide uptake inhibition) which 

precedes the adverse effect in a continuum of possible adverse biological effects of perchlorate 

exposure. NRC recommended that using a non-adverse effect that is upstream of the adverse effect 
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represents a more conservative, health-protective approach to the risk assessment for perchlorate, 

noting that the purpose of the 10-fold uncertainty factor is to protect sensitive subpopulations in the 

face of uncertainty regarding their relative sensitivity to perchlorate exposure. EPA has adopted the 

NRC’s recommendations in its “Integrated Risk Information System” (IRIS) (USEPA 2005), 

resulting in an RfD of 0.7 ug/kg/day, which was derived by applying a 10-fold (10x) uncertainty 

factor to the NOEL of 7.0 ug/kg/day. Greer MA, Goodman G, Pleus RC, Greer SE. Environ 

Health Perspect. 2002 Sep;110(9):927-37. Erratum in: Environ Health Perspect. 2005 

Nov;113(11):A732. National Research Council (NRC). 2005. Health Implications of Perchlorate 

Ingestion. National Academies Press, Board on Environmental Studies and Toxicology, January, 

2005, Washington, D.C. 276pp. USEPA. 2002. A review of the reference dose and reference 

concentration processes. Risk Assessment Forum, Washington, DC; EPA/630/P–02/0002F. 

USEPA. 2005. ‘‘Integrated Risk Information System (IRIS), Perchlorate and Perchlorate Salts.’’ 

February 2005. 

Commenter Name: Tatjana and Jeremy Thomas 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0669 

EPA Comment ID: 20242 

EPA Comment Code: 2500 

Comment: >From New York Times 3/2/04 ...".The study found crude effects on rats' brains from 

exposure to perchlorate. Parts of the brains were enlarged. ....In the same study, benign tumors were 

spotted on two 19-week-old baby rats out of a group of 30 whose mothers had been exposed to 

high levels of perchlorate. Scientists from the environmental agency say it is unusual to see tumors in 

baby rats that young, leading them to believe that something must have occurred in the womb." 

Concerned Citizen and a pregnant mother of two. 

Attachments 

EPA-HQ-OW-2008-0692-0669.1 Comment attachment submitted by T. Thomas 

EPA-HQ-OW-2008-0692-0669.2 Comment attachment submitted by T. Thomas 

Jeremy and Tatjana Thomas 40268 205th Avenue Pittsfield, IL 62363 (217) 285-5951 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 
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health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Crystal D. Lay 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1557 

EPA Comment ID: 20523 

EPA Comment Code: 2500 

Comment: 1. Perchlorate interferes with the functioning of the thyroid gland which can disrupt 

metabolism regulation in adults. However, the effects on children can be much worse causing 

irreversible developmental problems. This is particularly concerning when the U.S. Food and Drug 

Administration’s Total Diet Study: 

Dietary Intake of Perchlorate and Iodine study revealed that children two years of age have the 

highest total perchlorate intake per day and infants have the second highest perchlorate intake per 

day. 2. The RFD of .07 Âμg/kg translates to a drinking water equivalent of 24.5 ppb, based on 2 

liters consumed by an adult daily. However, this assumes that the only source of perchlorate is 

drinking water. The 2004-2005 Exploratory Survey Data on Perchlorate in Food Samples listed 

several foods that were found to have perchlorate. One milk sample revealed levels of over 10 ppb 

Âμg/L. Samples of green beans revealed levels as high as 25.9 ppb. Samples of oranges revealed 

levels as high as 23.3 ppb. This is alarming as these foods are all essential to growing children who 

may be more prone to higher levels of perchlorate already. The translated RFD of 0.7 Âμg/kg to 

24.5 ppb is calculated for adults. This level may be even lower for children and does not include any 

perchlorate intake from food they may consume. Another serious consideration is the seemingly 

high levels of perchlorate that could be consumed by infants if fed formula mixed with drinking 

water. For the reasons stated above, I urge EPA to reconsider setting a national maximum 

contaminant level for perchlorate in drinking water. The states that have already imposed a 

maximum contaminant level for perchlorate have set the standard much lower than 24.5 ppb, 

suggesting that those states have concluded that a safe level of perchlorate intake is less than 24.5 

ppb. 

Respectfully submitted, 

Crystal D. Lay 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 
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health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Jimmy Spearow 

Commenter Organization: Sacramento Chapter, Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-1672 

EPA Comment ID: 20589 

EPA Comment Code: 2500 

Comment: Dear EPA This is a Public Comment Regarding EPA's refusal to regulate Perchlorate 

under the Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692). 

Perchlorate is a chemical in rocket fuel that has been associated with decreased thyroid hormone 

levels in pregnant women, newborns and young children. Thyroid hormone is critical for growth 

and development, especially in the brains of fetuses and children. Perchlorate inhibits iodine uptake 

and the synthesis of thyroid hormone by the thyroid gland. The CDC showed that exposure to 

perchlorate levels as low as 5 ppb was associated with decreased thyroid hormone levels, especially 

in women with lower iodine levels. In other words, exposures at levels significantly lower than the 

level EPA assumes is "safe" i.e., the EPA RfD of 24.5 ppb, were linked to a lowering of thyroid 

hormone levels that can cause significant adverse health effects in exposed women and fetuses. 

Since over 16 million Americans are at risk of exposure to elevated levels of perchlorate, 

extrapolation of this study to the entire US population indicates that approximately 2 million women 

of childbearing age are at risk from abnormally low thyroid hormone levels. 

Adequate levels of thyroid hormone are also critical to normal growth and cognitive development in 

infants. Infants are likely to be particularly vulnerable to perchlorate since they have rapid turnover 

of thyroid hormone, as well as, low reserves of thyroid hormone. 

Response: EPA acknowledges and thanks you for providing comments. EPA will continue to 

evaluate the available science related to perchlorate. On August 19, 2009, EPA published a Federal 

Register notice requesting supplemental public comments on its preliminary determination not to 

regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 41883). In this August 

19, 2009 Federal Register notice, EPA requested comments on additional interpretation of data on 

the level of human health concern, perchlorate frequency of occurrence in drinking water, and the 

opportunity for health risk reduction through a national primary drinking water standard, to help 

determine if it should be regulated. EPA considers both the extent of national occurrence and the 

severity of health effects for a contaminant, as well as other factors (e.g., sources of exposure), when 

deciding whether regulation presents a meaningful opportunity for health risk reduction. Therefore, 

the Agency considered national occurrence and the severity of health effects from perchlorate and 

concluded that regulation was warranted, so EPA has determined that perchlorate will be regulated. 

Commenter Name: Carol Bigelow 

Commenter Organization: University of Massachusetts 

EPA Document ID: EPA-HQ-OW-2008-0692-1427 

EPA Comment ID: 20626 

EPA Comment Code: 2500 

Comment: NOVEMBER 10 2008 
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US Environmental Protection Agency Office of Water Docket (Mailcode: 2822T) 1200 

Pennsylvania Avenue, NW Washington, DC 20460 

RE: Comments on Regulatory Determination on Perchlorate Docket EPA-HQ- OW-2008-0692 

Drs. Carol Bigelow, Larry Schwartz, and R. Thomas Zoeller are pleased to submit comments to the 

US EPA on Docket ID No. EPA-HQ-OW-2008-0692, entitled "Drinking Water: Preliminary 

Regulatory Determination on Perchlorate". In brief, the authors of docket ID No. EPA-HQ-OW2008-0692 propose that there be no national primary drinking water regulation, the rationale being 

that such would not present a "meaningful opportunity for health risk reduction for persons served 

by public water systems". EPA’s proposal not to regulate perchlorate in public water systems: 

(1) Lacks the requisite scientific basis. Specifically, EPA regularly cites the nearly 4 year-old NAS 

report (NRC, 2005) without a critical evaluation of the science underlying the document and how 

new information should be integrated into it. This issue is most germane in the emphasis on the 

pregnant woman and fetus as the most sensitive population to perchlorate exposure. EPA fails to 

consider published, peer-reviewed data demonstrating that the current RfD for perchlorate exposure 

is not protective of neonates and infants (Ginsberg and Rice, 2005; Ginsberg et al., 2007). 

(2) Lacks critical evaluation of the literature employed to justify its decision. Methodologically sound 

research indicates an association between perchlorate exposure and thyroid function in adult women 

with low iodine intake (Blount et al., 2006a; Steinmaus et al., 2007). If infants are no more sensitive 

to perchlorate than adult women, brain damage will occur at the median level of perchlorate 

exposure, according to published data (reviewed by (Ginsberg et al., 2007) ). Thus, the CDC study 

should reasonably replace the 6 year-old "Greer Study" (Greer et al., 2002) as the point of departure 

for RfD development. 

(3) Fails to critically evaluate the reliability of null findings. EPA justifies ignoring the Blount Study 

using a series of studies that identify no relationship between perchlorate exposure and thyroid 

function in humans. However, EPA is apparently unaware of published data describing the 

variability of serum thyroid hormone measures in adults (Andersen et al., 2002; Andersen et al., 

2003) and in neonates (Herbstman et al., 2008a; Herbstman et al., 2008b). It is our opinion that 

critical analysis of the null findings employed by EPA to justify ignoring the findings in the Blount 

Study will demonstrate that these null findings cannot be interpreted to indicate no relationship 

between perchlorate exposure and thyroid function. 

(4) Relies on a PBPK model parameterized with weak data. It is discouraging that EPA went to the 

effort of obtaining the code for the Clewell et al. PBPK model and modified it without critically 

evaluating the data employed to parameterize the model. 

Considering these 4 points, it is our opinion that a scientifically valid RfD and HRL will be 

significantly lower than that the current proposal. Moreover, the data are available to scientifically 

defend a return to EPA’s draft RfD of 2002. 

Response: EPA acknowledges and thanks you for providing comments. EPA will continue to 

evaluate the available science related to perchlorate. On August 19, 2009, EPA published a Federal 

Register notice requesting supplemental public comments on its preliminary determination not to 
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regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 41883). In this August 

19, 2009 Federal Register notice, EPA requested comments on additional interpretation of data on 

the level of human health concern, perchlorate frequency of occurrence in drinking water, and the 

opportunity for health risk reduction through a national primary drinking water standard, to help 

determine if it should be regulated. EPA considers both the extent of national occurrence and the 

severity of health effects for a contaminant, as well as other factors (e.g., sources of exposure), when 

deciding whether regulation presents a meaningful opportunity for health risk reduction. Therefore, 

the Agency considered national occurrence and the severity of health effects from perchlorate and 

concluded that regulation was warranted, so EPA has determined that perchlorate will be regulated. 

Commenter Name: Carol Bigelow 

Commenter Organization: University of Massachusetts 

EPA Document ID: EPA-HQ-OW-2008-0692-1427 

EPA Comment ID: 20628 

EPA Comment Code: 2500 

Comment: Thyroid hormone insufficiency in the neonate and infant leads to irreversible health 

consequences. Defects in thyroid hormone regulation negatively impact brain development and may 

contribute to a cluster of irreversible neurological defects that includes autism. This literature - 

completely ignored by EPA’s analysis - is compelling public health rationale for regulating 

perchlorate exposure. 

Perhaps the best examples of infants’ unique sensitivity to thyroid hormone insufficiency are the 

studies of infants with congenital hypothyroidism (CH) (for review, see (Zoeller and Rovet, 2004)). 

These studies are particularly useful because subjects are under continuous medical surveillance so 

there is good documentation of the relationship between endogenous thyroid hormone, levels of 

hormone supplementation, and developmental outcome (Heyerdahl and Oerbeck, 2003). The 

neuropsychological outcome of children diagnosed with CH at birth is associated with both the 

severity of CH and early treatment factors (how soon T4 was administered, starting dose and serum 

T4 levels during the first two years of life). These T4 parameters were highly correlated with verbal 

IQ at age 20, and children with CH who ultimately completed high school had a significantly higher 

T4 starting dose than those who did not (Oerbeck et al., 2003). Strikingly, the difference in mean 

starting dose between these two groups was a modest 2.1 ug/kg-day. Because iodine represents 65% 

(w/w) of T4, the amount of iodine associated with that T4 difference was only 1.37 ug/kg-day. 

Independent studies were consistent in their findings. In Selva et al. (2002) and Selva et al (2005), a 

difference in starting dose of only 12.5 μg/day (8.13 ug/day iodine equivalent or 2.3 ug/kg/d) was 

associated with a significant difference in full scale IQ of 11 points (Selva et al., 2002; Selva et al., 

2005). Thus, small differences in available thyroid hormone (and the iodine associated with it) during 

the first few weeks of life can have significant lifetime consequences including, especially, reduced 

IQ. 

In addition, the experimental literature clearly demonstrates that specific neurodevelopmental events 

are irreversibly damaged by marginally-low thyroid hormone. These include neuronal migration 

(Lavado-Autric et al., 2003; Auso et al., 2004), synaptic function (Gilbert and Sui, 2006, 2008), white 

matter development (Sharlin et al., 2008), and the development of nodular heterotopias (Goodman 

and Gilbert, 2007). Each of these developmental events will have cognitive and neurological 

sequelae in humans. 
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In its unsupported reliance on the NAS report of 2005 (NRC, 2005), EPA did not focus their 

analysis on the relevant vulnerable groups, the neonate and infant. In this regard, EPA failed to 

employ one of the largest, and critically relevant, data sets relating thyroid hormone to health 

consequences - that of neonates and infants (see (Chan and Rovet, 2003; Zoeller and Rovet, 2004)). 

The superficial reference EPA makes to the infant is wholly inadequate in the current version of this 

document and should take into consideration the issues developed above and expanded previously 

(Ginsberg et al., 2007). In addition, EPA should review the issue of genetic factors that may impact 

individual sensitivity to perchlorate exposure (Scinicariello et al., 2005). Due consideration to this 

published literature will dramatically change the EPA’s analysis. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Carol Bigelow 

Commenter Organization: University of Massachusetts 

EPA Document ID: EPA-HQ-OW-2008-0692-1427 

EPA Comment ID: 20631 

EPA Comment Code: 2500 

Comment: Also lacking in the science presented in docket ID No. EPA-HQ-OW-2008-0692 are 

the power considerations necessary to inference making that is precise. Indeed, several of the studies 

relied upon by the US EPA lacked the statistical power needed to rule out a non-null association. 

EPA has failed to address key questions regarding the studies it uses to defend ignoring the CDC 

study. Specifically, given the known variability in measures of thyroid function (Andersen et al., 

2002; Andersen et al., 2003) and maternal, infant and delivery factors on neonatal and thyroid status 

(Herbstman et al., 2008a; Herbstman et al., 2008b), to what extent do epidemiological studies 

exploring the relationship between perchlorate and thyroid function provide reliable evidence of a 

null relationship? Andersen et al. (Andersen et al., 2003) discuss the sources of variability in 

measures of thyroid hormone in adults. These are critical considerations to employ in estimating the 

ability of epidemiological studies to identify relationships of interest between perchlorate and thyroid 

function. Moreover, Andersen et al. (2002) found that to identify the homeostatic set-point within 

5% precision required 85 individual measures of TSH and 25 of total T4. Given this degree of 

variation, studies comparing average measures of thyroid function and proxy measures perchlorate 

exposure have little - if any - ability to identify relationships of interest. Therefore, EPA is required 

to determine which of the epidemiological studies it used in its analysis had the potential to identify 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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a relationship between perchlorate exposure and thyroid function, and the degree to which null 

findings are meaningful. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Brie Brigham 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1436 

EPA Comment ID: 20894 

EPA Comment Code: 2500 

Comment: Perchlorate interferes with iodine uptake in the thyroid gland, leading to low thyroid 

production, termed hypothyroidism. Perchlorate also impedes the thyroid's ability to produce 

hormones that foster mental and physical development. Robert Zoeller, a professer at the University 

of Massachusetts who specalizes in thyroid hormone and brain development stated a reduction in 

thyroid function in fetuses, newborns, and children could translate to a loss of IQ and an increase in 

behavior and perception problems. Zoeller also stated that the impacts are irreversible, meaning that 

even small changes in thyroid functions in early life have impacts on functioning through high 

school and even into people's early twenties. 

Response: EPA acknowledges and thanks you for providing additional information related to 

perchlorate. EPA will continue to evaluate the available science related to perchlorate. On August 

19, 2009, EPA published a Federal Register notice requesting supplemental public comments on its 

preliminary determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, 

No. 159, p. 41883). In this August 19, 2009 Federal Register notice, EPA requested comments on 

additional interpretation of data on the level of human health concern, perchlorate frequency of 

occurrence in drinking water, and the opportunity for health risk reduction through a national 

primary drinking water standard, to help determine if it should be regulated. EPA considers both the 

extent of national occurrence and the severity of health effects for a contaminant, as well as other 

factors (e.g., sources of exposure), when deciding whether regulation presents a meaningful 

opportunity for health risk reduction. Therefore, the Agency considered national occurrence and the 

severity of health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Caroline Baier-Anderson, PhD 

Commenter Organization: Environmental Defense Fund 
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Page 229 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20944 

EPA Comment Code: 2500 

Comment: New data indicate that increases in TSH, resulting from decreased circulating thyroid 

hormones, may also increase perchlorate uptake in the thyroid (Tran et al. 2008). 

There are critical windows in fetal, neonatal, and infant development where insufficient thyroid 

hormones are associated with disruptions in neural development leading to cognitive deficits 

(Woodruff et al. 2008). The NIS is expressed in the placenta, and a recent study has shown that the 

NIS can transport perchlorate across the placental barrier and lead to increased exposure to the 

developing fetus (Tran et al. 2008). It is therefore not unreasonable to suggest that perchlorate 

transport could be exacerbated by low maternal thyroid hormones that stimulate TSH release, which 

enhances perchlorate transport into the maternal thyroid, and across the placental barrier (Tran et al. 

2008). Several studies have shown that even moderate maternal thyroid hormone insufficiency 

during these critical developmental windows can have a significant and lasting impact on the child, 

such as reduced IQ scores (Haddow et al. 1999; Morreale de Escobar et al. 2000; Pop et al. 2003). 

Comprehensive studies of the impact of perchlorate exposure on children of mothers that have low 

iodine intake are lacking, and increased research in this area is needed. 

This problem is complicated by extensive individual variability such that the current ranges used to 

assess thyroid health may not effectively identify adverse downstream effects (Anderson et al. 2002). 

Therefore, the focus on modulation of thyroid hormones rather than clinical endpoints may be 

warranted because important concerns have been raised regarding the current method used to assess 

thyroid health, specifically comparison of thyroid hormone levels with pre-defined acceptable 

ranges. In their study Anderson et al conclude: "we found that individual reference ranges for serum 

T3 and T4 are about half the width of population based reference ranges. Hence, a test result within 

the laboratory reference limits is not necessarily normal for the individual." This is consistent with, 

and may help explain the observation discussed above, that even small decrements in maternal T4 

that do not constitute clinical hypothyroidism can impact neurological development in children. In 

fact, there is evidence that hypothyroidism is prevalent in the US, yet often undetected, and 

untreated (Aoki et al. 2007) 

An additional complicating factor is that Centers for Disease Control and Prevention (CDC) data 

indicate that over thirty percent of US women are not obtaining sufficient iodine (Caldwell et al. 

2005). Insufficient iodine intake can predispose the thyroid gland to adverse effects of endocrine 

disrupters especially under phases of vulnerability during development and under adaptive 

challenges during diseases (Kohrle 2008). Thus, insufficient iodine intake could increase vulnerability 

to perchlorate. Insufficient iodine intake, assessed by comparing urinary iodine excretion to World 

Health Organization standards for iodine sufficiency, can increase sensitivity to uptake inhibition by 

perchlorate. 

These major factors described above and summarized below present a clear case that perchlorate 

exposure poses a significant health risk in the US: 

* The principle mode of action of perchlorate is inhibition of iodide uptake by the thyroid, * More 

than thirty percent of US women are not getting sufficient iodine, * Hypothyroidism is prevalent in 
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Page 230 of 1099

the US population, yet often undetected and untreated, * Neurological damage can occur in babies 

born to with subclinical hypothyroidism. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20990 

EPA Comment Code: 2500 

Comment: 2. EPA is ignoring data that demonstrates setting an MCL for perchlorate will provide a 

meaningful opportunity for health risk reduction 

A. Data since the NRC report suggest that perchlorate is even more hazardous than previously 

thought. 

Even based on older studies, EPA acknowledged in its preliminary determination that perchlorate 

may have adverse health effects. More recent studies show that the effects on humans may be even 

more dangerous than EPA thought. 

Data showing that perchlorate is actively transported into mammary epithelial cells by the sodium 

iodide symporter (NIS), resulting in an accumulation of perchlorate in breast milk[FN23: Dohan, O, 

C Portulano, C. Basquin, A Reyna- Noyra, LM Amzel, and N Carrasco. 2007. The Na+/Isymporter (NIS) mediates electroneutral active transport of the environmental pollutant perchlorate. 

PNAS 104(51):20250-20255.][FN24: Dasgupta, P. K., Kirk, A. B., Dyke, J. V., and Ohira, S.-I. 

(2008). Intake of Iodine and Perchlorate and Excretion in Human Milk. Environ. Sci. Technol. 42, 

8115-8121. Docket HQ-OW-2008-0692 NRDC comments on perchlorate HRL] suggests that 

perchlorate may not only inhibit iodide accumulation in maternal milk but also could be transferred 

through milk to the nursing infant where it would be predicted to inhibit iodide uptake in the 

infant's thyroid gland. The NIS also is found in the placenta and based on this new research, it 

seems likely that perchlorate is actively transported across the placenta. Because the fetus and 

developing infant require adequate iodide for thyroid hormone function, any determination of a safe 

level of exposure to perchlorate should take into account this mode of action for perchlorate 

toxicity. 
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Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 21002 

EPA Comment Code: 2500 

Comment: C. Sensitive populations not protected by HRL 

A related study estimates perchlorate doses that correspond to urinary perchlorate excretion 

(hereinafter referred to as "Blount (2007)").[FN62: Blount BC, Valentin-Blasini L, Osterloh JD, 

Mauldin JP, Pirkle JL. Perchlorate exposure of the US Population, 2001-2002. J Expo Sci Environ 

Epidemiol. 2007 Jul;17(4):400-7. Epub 2006 Oct 18.] These calculations are feasible because 

perchlorate is not metabolized and has a short half-life of approximately 8 hours[FN63: Ibid.]. 

Blount (2007) showed that the adjusted geometric mean for perchlorate exposure in women was 

0.059 ug/kg-day, and the 95th percentile exposure was 0.215 ug/kg-day. This means that the adverse 

effects described by Blount (2007) are occurring at perchlorate exposures below the RfD of 0.7 

ug/kg- day, with the logical inference being that the proposed HRL will not protect sensitive 

subpopulations. 

A study by Ginsburg et al.[FN64: GL Ginsburg, DB Hattis, RT Zoeller, and DC Rice. 2007. 

Evaluation of the U.S. EPA/OSWER preliminary remediation goal for perchlorate in groundwater: 

Focus on exposure to nursing infants. Environ Health Perspect. 115(3):361-369. 

http://www.ehponline.org/members/2006/9533/9533.html] published since the NRC review 

found that, "drinking-water perchlorate must be < 6.9 ug/L to keep the median, and < 1.3 ug/L to 

keep the 90thpercentile nursing infant exposure below the RfD."[FN65: GL Ginsburg, DB Hattis, 

RT Zoeller, and DC Rice. 2007. Evaluation of the U.S. EPA/OSWER preliminary remediation goal 

for perchlorate in groundwater: Focus on exposure to nursing infants. Environ Health Perspect. 

115(3):361-369.] Based on both exposure and toxicity information, and data on sensitive 

populations, the proposed HRL, which is twice as high as the limit proposed by Ginsberg et al, will 

leave significant portions of the population at risk. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 
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determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21057 

EPA Comment Code: 2500 

Comment: This year, the ATSDR released its Toxicological Profile for Perchlorates (2008) as new 

data have become available since the last profile of perchlorates in 2005. As a part of their review, 

ATSDR derives minimum risk levels (MRLs) using available peer reviewed information. MRLs 

"...are derived when reliable and sufficient data exist to identify the target organ(s) of effect or the 

most sensitive health effect(s) for a specific duration for a given route of exposure. An MRL is an 

estimate of the daily human exposure to a hazardous substance that is likely to be without 

appreciable risk of adverse noncancer health effects over a specified duration of exposure. MRLs are 

based on noncancer health effects only and are not based on a consideration of cancer effects. These 

substance-specific estimates, which are intended to serve as screening levels, are used by ATSDR 

health assessors to identify contaminants and potential health effects that may be of concern at 

hazardous waste sites. It is important to note that MRLs are not intended to define clean-up or 

action levels" (ATSDR, 2008). Considering the NRC report along with new studies published since 

the NRC report, "ATSDR has adopted the EPA's chronic RfD recommended by the NRC (2005) 

for the chronic MRL" (ATSDR, 2008). 

ATSDR based their MRL on the same most sensitive population, pregnant women and their fetuses, 

although they also discussed other sensitive populations, preterm and nursing infants. They also 

state that their decision "...was made after a careful evaluation of the NRC report and of studies that 

have been published after the NRC (2005) report. The results from newer studies do not change the 

bottom-line recommendation" (ATSDR, 2008). 

The ATSDR Toxicological Profile for Perchlorates was peer reviewed and made available for public 

comments. "The expert peer reviewers on April 18, 2007 concluded that the MRL should still be 

based on the RfD as recommended by the NRC Panel Report (2005) given the research data 

available at the time of the 2007 peer review" (ATSDR, 2008). 

Based on the traditional and foundational approach used in science, the weight of evidence-or the 

number of well conducted studies in humans and animals with appropriate dose-response 

information-supports EPA's decision not to establish a NPDWR. As shown in the assessment by 

the NRC in 2005 and the subsequent literature published since then, including the ATSDR 

Toxicological Profile, the weight of evidence shows that, 
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* inhibition of iodide uptake in the thyroid gland is a key biochemical event, * the inhibition of 

iodide uptake is not an adverse effect, * there are doses of perchlorate below which inhibit iodide 

uptake in healthy adults, * the dose of perchlorate that might be sufficient to cause an adverse effect 

is as sustained exposure greater than 0.4 mg/kg-d (NRC, 2005), and * there are natural occurring 

agents, such as thiocyanate and nitrate, that also effect iodide uptake in the thyroid gland. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21060 

EPA Comment Code: 2500 

Comment: The weight of evidence shows that the fetal brain is more sensitive to hypothyroidism 

than the neonate or infant brain (Boelaert and Franklyn, 2005). Breast milk concentrations of 

perchlorate have been measured at levels greater than the HRL (Kirk et al., 2005; Pearce et al., 

2007b). However, the RfD assumes that if a person consumes 15 ppb of perchlorate not just once, 

but every day for a lifetime, they will be consuming a concentration of perchlorate that is not 

anticipated to cause an adverse effect. Furthrermore, a HRL, MRL, PHG[FN1: A Public Health 

Goal, or PHG, is the State of California's acceptable level of a chemical in drinking water that is not 

expected to cause an adverse effect if consumed every day for a lifetime.], RfD, etc. are not bright 

lines above which health effects would be expected to occur. As noted with perchlorate, an RfD 

based on a no effect level for a non adverse effect in humans with an additional 10-fold uncertainty 

("safety") factor provides a health protective approach. The development of a value lower than the 

RfD will only increase the level of caution. Therefore, if an infant consumes one dose of perchlorate 

that is greater than the RfD, it is not expected to be any more harmful than a lesser dose. Lastly, a 

solely breast fed infant will not have exposures through other media. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 
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drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21061 

EPA Comment Code: 2500 

Comment: II. KEY SCIENTIFIC STUDIES PUBLISHED SINCE 2005 

Since the publication of the NRC report in 2005, several studies have been published that support 

the conservative nature of the current EPA RfD. Overall, these studies demonstrate that perchlorate 

is a ubiquitous chemical in the environment, food, and the human body. In a recent study by Blount 

et al. (2007), all samples of urine measured had low, but detectable concentrations of perchlorate. 

The sources of perchlorate appear to be both natural and anthropogenic. There is an increasing 

body of literature demonstrating that much of the environmental perchlorate may be natural or due 

to non-point sources (DasGupta et al., 2005; SERDP, 2005; DasGupta et al., 2006; Rajagopalan et 

al., 2006). 

[Text Box: The weight-of-evidence of human and animal studies that include sufficient doseresponse data, show that possible adverse health effects are several orders of magnitudes above 

environmentally-relevant levels of perchlorate and that the current RfD is a conservative toxicity 

guideline value such that contaminants present in drinking water at or below the HRL of 15 ppb 

would pose no significant health risk to the most sensitive individuals who consume the water on a 

daily basis over a lifetime.] 

Despite the widespread low levels of perchlorate in the environment, studies have not demonstrated 

an adverse effect due to perchlorate exposure. The NRC report states, 

"The committee emphasizes that inhibition of iodide uptake by the thyroid has been the only 

consistently documented effect of perchlorate exposure in humans. The continuum of possible 

effects of iodide-uptake inhibition caused by perchlorate exposure is only proposed and has not 

been demonstrated in humans exposed to perchlorate (with the exception that in patients with 

hyperthyroidism doses of 200 mg daily or higher may reduce thyroid secretion). More important, the 

outcomes at the end of the continuum are not inevitable consequences of perchlorate exposure." 

(NRC, 2005)[FN2: The noted dose of 200 mg/d is a conservative therapeutic value. When use of 

perchlorate to treat hyperthyroidism was common, doses of 400 mg/d were commonly prescribed, 

but were found to be slow to control thyrotoxicity and doses needed to be repeated 4 to 5 times/d, 

due to the rapid excretion of the drug. Although it still took an average of 9.4 weeks, doses of up to 

2000 mg/d were given to reduce hyperthyroidism to a remission state (Wolff, 1998).] 
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The new studies contribute to an already well developed database, adding more studies that are 

consistent with previous analyses. Furthermore, additional studies that are consistent with the 

literature also reduces uncertainty (reducing "what we do not know"), thereby reinforcing that the 

current RfD for perchlorate is both conservative and health protective. Thus, perchlorate 

concentrations equal to or above the EPA-recommended HRL of 15 ppb in water would also be 

conservative and health protective for sensitive populations. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21062 

EPA Comment Code: 2500 

Comment: A. Environmental Studies 

EPA states: "If adequate human studies (confirmed for validity and applicability) exist, these studies 

are given first priority in the dose- response assessment, and animal toxicity studies are used as 

supportive evidence." and "If adequate human data are available, this information is used as the 

basis of the RfD (EPA, 1989). The scientific studies regarding perchlorate and health are 

predominately based upon human data, with a range of parameters and dose-response data. The 

types of human studies are clinical, occupational, or ecological. To date, there is only one 

epidemiological study which measures perchlorate exposures and outcomes in pregnant women and 

neonates (Tellez et al., 2005). In contrast to ecological studies measuring collective exposures and 

outcomes, an epidemiological study measures individual exposure and outcome. There are also some 

well designed animal studies that have contributed to the health effects database. Many of these 

studies investigate the relationship between perchlorate exposure and adverse outcomes among 

especially vulnerable groups. In addition to the clinical studies reviewed by NRC, epidemiological 

studies are valuable in exploring the health effects due to perchlorate in a chronically exposed 

genetically-diverse population that includes the population of concern (pregnant women and their 

fetuses). 

In the EPA notice, several of these association studies were taken together, leading EPA to conclude 

that the results of "...studies of the effects of perchlorate exposure on hormone levels have been 

mixed" (p. 60266), citing Amitai et al. (2007) showing no effects and Blount et al. (2006) identifying 
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hormonal changes (although none were outside normal ranges). However, when the strength of the 

study design is taken into consideration, the weight-of-evidence demonstrates that the current RfD 

is a conservative toxicity guideline value such that contaminants present in drinking water at or 

below the HRL of 15 ppb would pose no significant health risk to the most sensitive individuals 

who consume the water on a daily basis over a lifetime. 

Response: EPA acknowledges and thanks you for providing additional information related to 

perchlorate. EPA will continue to evaluate the available science related to perchlorate. On August 

19, 2009, EPA published a Federal Register notice requesting supplemental public comments on its 

preliminary determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, 

No. 159, p. 41883). In this August 19, 2009 Federal Register notice, EPA requested comments on 

additional interpretation of data on the level of human health concern, perchlorate frequency of 

occurrence in drinking water, and the opportunity for health risk reduction through a national 

primary drinking water standard, to help determine if it should be regulated. EPA considers both the 

extent of national occurrence and the severity of health effects for a contaminant, as well as other 

factors (e.g., sources of exposure), when deciding whether regulation presents a meaningful 

opportunity for health risk reduction. Therefore, the Agency considered national occurrence and the 

severity of health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21070 

EPA Comment Code: 2500 

Comment: In a peer-reviewed letter to the editor of Thyroid, Gibbs and Van Landingham (2008) 

reviewed data from their previously published study (Tellez et al., 2005), and showed that in a cohort 

of pregnant women in Chile, the data do not support the association between environmental 

perchlorate exposure and changes in thyroid hormones and are consistent with the recent negative 

findings by both Pearce et al. (2007b) and Lamm et al. (2008), both presented at the Seattle SOT 

meeting. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Michael Girard 
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Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21074 

EPA Comment Code: 2500 

Comment: B. Occupational or Clinical Studies 

i. Braverman et al. (2005) 

This study included 29 workers exposed for at least 1.7 years in an ammonium perchlorate plant and 

12 unexposed volunteers; variables measured in the study included serum perchlorate, thiocyanate, 

nitrate, total T4, Free T4, total T3, Tg, and TSH; RAIU; and urinary iodine and perchlorate taken 

after 3 days off or 3 days working. The authors estimated that "half of the workers experienced 

average ClO4- doses in excess of 0.33 mg/kg-shift over the year preceding this study." They found 

that there was a decrease in RAIU, but no change in thyroid hormones compared to unexposed 

controls. There was a slight increase in T3, T4, and free T4 after 3 days working compared to 3 days 

off. Again, the NRC committee has stated that "The committee does not think that transient 

changes in serum thyroid hormone or TSH concentrations are necessarily adverse effects" (NRC, 

2005). The RAIU dose response curve the authors found was consistent with that of Greer et al. 

(2002). 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21075 

EPA Comment Code: 2500 

Comment: ii. Braverman et al. (2006) 

In an effort to study the thyroidal effects of a prolonged (six months) exposure to low perchlorate 

levels in humans, Braverman et al. exposed 13 healthy volunteers to 0, 0.5, or 3.0 mg/d of potassium 

perchlorate and measured urinary perchlorate levels, radioactive iodine uptake and serum T3, free 

T4, TSH and Tg concentrations. The 0.5 and 3.0 mg/d doses are equivalent to 250 and 1500 ppb, 

respectively, assuming a daily water ingestion of 2 liters. The authors concluded that perchlorate at 
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doses of up to 3 mg/day for six months "...had no effect on thyroid function, including inhibition of 

thyroid iodide uptake as well as serum levels of thyroid hormones, TSH and Tg" and, "...there was 

no significant change in the thyroid RAIU during perchlorate administration." (emphasis added) 

This study was similar to Greer et al. (2002), but for longer exposures. The doses were 0.5 and 3.0 

mg/d and the exposures were for six months. This study also did not restrict or control for dietary 

intake (Crawford-Brown et al., 2006).[FN6: "If one assumes that the individuals in the study by 

Greer et al. (2002) were exposed to the same background levels of perchlorate as the rest of the U.S. 

population (there is nothing in their diets or in the study design to preclude this), then no further 

RSC adjustment is needed to reflect total exposures via all routes because the risk coefficient from 

the study already reflects the incremental risk from ingestion of perchlorate in water above and 

beyond the contributions to perchlorate exposure via the other routes" (Crawford-Brown et al., 

2006).] Therefore, the doses administered as part of this study were in addition to the background 

levels of perchlorate ingested-the impact of dietary iodine intake was not accounted for. The study 

would have benefited from a larger sample size; however, data from the 14-day Lawrence et al. 

(2000, 2001) studies, and the Greer Study support the results reported by Braverman et al. These 

studies all support the NOEL determined by Greer et al. (2002), and relied upon by the NRC as the 

basis for its recommended RfD. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Ladd Larry 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0037 

EPA Comment ID: 28337 

EPA Comment Code: 2500 

Comment: Larry Ladd says regulate. Data gap 1: Chronic effects of ClO4- in the skin. Half-life is 

longer than in the thyroid or the blood (Yu et al 2002, pubmed id 12140178). No discussion of how 

ClO4- causes drug-induced lupus and erythema nodosum (Beickert & Heinicke 1968, pmed id 

4181403), the role I- sometimes plays in relieving erythema nodosum (Boyd 2007, pmed id 

17618179; Sterling & Heymann 2000, pmed id 11004629), or similar ailments caused by chaotropic 

anions such as iododerma, bromoderma, and bromism. Data gap 2: Variation in infant renal 

excretion of ClO4-. If pendrin is important in ClO4- as well as I- excretion (for I- see Kim et al -- 

pmed id 19605545) , expect infant with acidosis (including low HCO3- from chronic diarrhea?) to 

retain more ClO4- (Frische et al 2003, pmed id 12556366). Data gap 3: Chaotropic effects 
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preventing immuno- coagulation such as opsonization of B-19 parvovirus by IgG (Chehadeh et al 

2009, pmed id 19450862, with the parvovirus outbreaks in Dharan after Patriot missile deployment, 

Mallouh & Qudah 1995 pmed 7715986 [corrected per commenter's request, see docket ID 

08090372] and western Pennsylvania during peak fireworks production, Beigi 2008, pmed id 

18464909 in mind); opsonization of staph by pentraxin 3, which is dependent on a cysteine array 

(Holland et al, 2009 pmed id 19054079; Inforzato et al 2008, pmed id 18223257); defensin adhesion 

to coccidoidomycosis, H. pylori, mycobacteria, and influenza, which is also dependent on a cysteine 

array vulnerable to changes in salinity (Chandrababu et al 2009, pmed 19480463). Analysis is lacking 

of NIS and SCN- in the airway (Fragoso et al 2004 pmed id 15345749; Pedemonte et al 2007 pmed 

id 17404297; Wang et al 2006 pmed id 17142773) and nitrosation in the gastrointestinal tract (Suzuki 

et al 2003 pmed id 12940440). In regards to humoral immunity, you need to evaluate the thickening 

of rat pup corpus callosum recorded in York et al 2005 (pmed id 16393938) with the migration 

paths of cd34+ stem cells within the rat brain (Jendelova et al 2005 pmed id 15929552). 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Steve Lamm 

Commenter Organization: Consultants in Epidemiology and Occupational Health, LLC (CEOH) 

EPA Document ID: EPA-HQ-OW-2009-0297-0654 

EPA Comment ID: 28487 

EPA Comment Code: 2500 

Comment: Is there an adverse neurodevelopmental effect with perchlorate exposure in an iodinesufficient population? 

Are moderate perchlorate exposures associated with adverse neurodevelopmental or cognitive 

outcomes? The ecological study Chang et al. (2003) showed there was no increase in ADHD or 

autism or decrease in fourth-grade performance with perchlorate levels up to 24 ug/L in Nevada. 

This study was done in the US iodine-sufficient population without distinguishing those with low 

iodine levels. The Lamm and Dohmland (1999) study found no increased incidence rate of 

congenital hypothyroidism in California and Nevada counties with perchlorate drinking water levels 

in the range of 4-16 ug/L. 

Are moderate perchlorate exposures associated with lower levels of neonatal thyroxine (or elevated 

neonatal TSH)? Li et al. (2000a) and Li et al. (2000b) showed no effect on neonatal thyroxine levels 
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or neonatal TSH levels, respectively, from environmental exposures to perchlorate that ranged up to 

15 ug/L, also in Nevada. 

At background levels of perchlorate exposure, are lower levels of neonatal thyroxine in the 

physiological range associated with adverse neurodevelopment outcome including cognition? Soldin 

et al. (2002) and Soldin et al. (2003) showed in case-control studies that neither childhood ADHD 

nor pediatric neurobehavioral diseases, respectively, were impacted by variations in neonatal 

thyryroxine levels. These studies were conducted in Washington, DC, whose water supply has no 

known perchlorate contamination. Recently, Oken et al. (2009) have demonstrated from a 

prospective cohort study of 500 children in Massachusetts that cognitive test scores at ages 6 month 

and 3 years were not associated with lower neonatal thyroxine levels. Further, newborn thyroxine 

levels were not associated with maternal measures of thyroid function (thyroxine, TSH or 

thyroperoxidase antibody levels). 

Are background perchlorate exposures associated with adverse maternal thyroid function measures? 

Pearce et al. (2007) presented results demonstrating that maternal thyroid function is not affected by 

environmental perchlorate exposure, based on urinary perchlorate levels of first trimester pregnant 

women in Cardiff, UK, where the population is mildly iodine-deficient (i.e, median = 90 ug/L). 

Pearce et al. (2008) expanded the study in Turin, Italy, asking the same question for an iodinedeficient population. 

Pearce et al. (2008) showed among 526 first trimester pregnant women in Turin, Italy, an 

iodinedeficient population with a median urinary iodine value of 50 ug/L, that there was no 

association between urinary perchlorate levels and free T4 levels (r2<0.0001, p = 0.9) or serum TSH 

(r2=0.002, p = 03). Their results were the same when they limited their analysis to the 433 women 

with urinary iodine values less than 100 ug/L. They concluded that "These results, from the largest 

sample to date of women with low urinary iodine values, do not support the findings reported in the 

U.S. that similar levels of perchlorate exposure increase serum TSH and lower serum T4 in women 

with urine iodine concentrations < 100 ug/L." 

The Pearce et al. (2008) study is a direct test of the hypothesis raised by the Blount et al. (2006) 

study, and, in particular for the population of great interest, pregnant women. This study is currently 

undergoing peer-review for the medical literature. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 241 of 1099

Commenter Name: Steve Lamm 

Commenter Organization: Consultants in Epidemiology and Occupational Health, LLC (CEOH) 

EPA Document ID: EPA-HQ-OW-2009-0297-0654 

EPA Comment ID: 28488 

EPA Comment Code: 2500 

Comment: In summary, the published studies demonstrate no adverse effect on infant thyroidal or 

neurodevelopmental health from perchlorate exposures up to 16-24 ug/L and no effect on 

neurodevelopmental or cognitive health with variations in normal neonatal thyroxine levels. 

Maternal thyroidal function has not been affected by background perchlorate levels either among 

UK women in a mildly iodine-deficient population or among Italian women in an iodine-deficient 

population, even those Italian women with urinary iodine levels less than 100 ug/L. These results 

challenge the interpretation of the Blount et al. (2006) analyses of the NHANES 2001-2002 crosssectional database. 

These comments are respectively submitted. I would be happy to supply any reference material that 

is not already in the record, and I keep myself open to participate in any further scientific discussions 

on these matters. 

Cordially, Steven H. Lamm, MD, DTPH Consultants in Epidemiology and Occupational Health, 

LLC. 3401 38th street, NW #615 Washington, DC 20016 202/333-2364 Steve@CEOH.com 

Associate in Department of Health Policy and Management Johns Hopkins University-Bloomberg 

school of Public Health Assistant Professor, Department of Pediatrics (Epidemiology) Georgetown 

University 

References: 

Blount BC, Pirkle JL, Osterlich JD, Valentin-Blasini L, and Caldwell KL (2006). Urinary Perchlorte 

and Thyroid Hormone Levels in Adolescents and Women Living in the United States. Environ 

Health Persp., 2006 Dec;114(12):1865-1871. 

Steinmaus C, Miller MD, and Howd R (2007). Impact of Smoking and Thiocyanate on Perchlorate 

and Thyroid Hormone Associations in the 2001-2002 National Health and Nutrition Examination 

Survey. Environ Health Perspec, 2007 Sept;115(9):1333-1338. 

Rasmussen LB, Ovensen L, and Christiansen E (1999). Day-to-day and within-day variation in 

urinary iodine excretion. Eur J Clin Nutri, 1999; 53:401-407. 

Andersen S, Pedersen KM, Pederson IB, and Laurberg P (2001). Variations in Urinary iodine 

Excretion and Thyroid Function. A 1-year study in healthy men. Eur J Endocr, 2001; 144:461-465. 

Laurberg P. Andersen S, Bjarnadottir RI, Carle A, Hreidarsson AB, Knudsen N, Ovesen L, 

Pedersen IB, and Rasmussen LB (2007). Evaluating Iodine Deficiency in Pregnant Women and 

young Infants - Complex Physiology with a Risk of Misinterpretation. WHO Public Health 

Nutrition, 2007;10(12A):1547-1552.. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Lamm SH, Hollowell JG, Engel A, and Chen R (2007). Perchlorate, Thyroxine, and Low Urine 

Iodine Association not seen with Low Creatinine-adjusted Urine Iodine Among Women of Childbearing Age. Thyroid, 2007;17:S51. 

Vanderver GB, Engel A, and Lamm S (2007). Cigarette Smoking and Iodine as Hypothyroxinemic 

Stressors in U.S. Women of Childbearing Age: A NHANES III Analysis. Thyroid, 2007; 17(2):741-

746. 

Chang S, Crothers C, Lai S, and Lamm S (2003). Pediatric Neurobehavioral diseases in Nevada 

Counties with respect to Perchlorate in Drinking Water; An Ecological Inquiry. Birth Defects Res 

part A, 2003; 67:886-892. 

Lamm SH and Dohmland M (1999). Has Perchlorate in Drinking Water Increased the Rate of 

Congenital Hypothyroidism? J Occ Env Med, 1999; 41(5):409-411. 

Li Z, Li FX, Byrd D, Dehyle GM, Sesser DE, Skeels MR, and Lamm SH (2000a). Neonatal 

Thyroxine Level and Perchlorate in Drinking Water. J Occ Env Med, 2000; 42(2):200-205. 

Li FX, Byrd DM, Deyhle GM, Sesser DE, Skeels MR, Katkowsky SR, and Lamm SH (2000b). 

Neonatal Thyroid-Stimulating Hormone Level and Perchlorate in Drinking Water. Teratology, 2000; 

62:429-431. 

Soldin OP, Nandedkar AKN, Japal KM, Stein M, Mosee S, Magreb P, Lai S, and Lamm SH (2002). 

Newborn Thyroxine Level and Childhood ADHD. Clinical Biochemistry, 2002; 35;131-136. 

Soldin OP, Lai S, Lamm SH, and Mosee S (2003). Lack of a Relation Between Human Neonatal 

Thyroxine and Pediatric Neurobehavioral disorders. Thyroid, 2003; 13(2):193-198. 

Oken E, Braverman LE, Platek D, Mitchell ML, Lee SL, and Pearce EN (2009). Neonatal 

Thyroxine, Maternal Thyroid Function, and Child Cognition. J Cin Endo Metab, 2009;94(2):497-

503. 

Pearce EN, Lazarus JH, Smythe PP, He X, Dall'Amico D, Parkes AB, Smith DF, Burns RA, MAina 

A, Leung AM, and Braverman LE (2007). Thyroid Function is Not Affected by Environmental 

Perchlorate Exposure in first Trimester Pregnant Women. Abstract # 275, 78th annual meeting of 

the American thyroid Association as cited (reference #18) in Brent GA, Braverman LE, and Zoeller 

(2009) Invited Editorial: thyroid Health and the Environment. Thyroid, 2009; 17(9):807=809. 

Pearce EN, Lazarus JH, Smyth PP, He X, Dall'Amico D, Parkes AB, Rurns R, Smith DF, Leung 

AM, and Braverman LE (2008). Thyroid Function is Not Affected by Environmental Perchlorate 

Exposure among Iodine-Deficient Euthyroid First Trimester Pregnant Women. Endocrine Society 

meeting (2008) abstract. 

Attached are copies of the citations Rasmussen and Andersen cited in my submission: Comment 

Tracking Number: 80a3e697. [See PDF docket ID EPA-HQ- OW-2009-0297-0655; note this is 

copyrighted materials] 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Attached are copies of the citation by Laurberg cited in my submission: Comment Tracking 

Number: 80a3e697. [See PDF docket ID EPA-HQ-OW-2009-0297-0656; note this is copyrighted 

material] 

Attached are copies of the citation by Oken cited in my submission: Comment Tracking Number: 

80a3e697. I hereby submit to your record by reference the three submissions we made to the record 

of the EPA Office of the Inspector General on March 10, 2009. That includes the Vanderver and 

Lamm papers and the two Lamm abstracts. [See PDF docket ID EPA-HQ-OW-2009-0297-0657; 

note this is copyrighted material] 

Attached are copies of the citations Pearce 2007 and Pearce 2008 cited in my submission: Comment 

Tracking Number: 80a3e697. [See PDF docket ID EPA-HQ- OW-2009-0297-0658] 

These is the cover letter to our submission on Vanderver March 10, 2009 to the EPA OIG and the 

article. [See PDF docket ID EPA-HQ-OW-2009-0297-0659] 

Here are submission 2 to the EPA-OIG March 10, 2009. [See PDF docket ID EPA-HQ- OW-2009-

0297-0660] 

This is submission 3 to the EPA_OIG concerning iodine supplementation. This is the cover letter. 

It will not accept the abstract, so I will send it separately. [See PDF docket ID EPA-HQ-OW-2009-

0297-0661] 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: James D. Taft 

Commenter Organization: Association of State Drinking Water Administrators 

EPA Document ID: EPA-HQ-OW-2009-0297-0525 

EPA Comment ID: 28503 

EPA Comment Code: 2500 

Comment: EPA discusses but does not ask for any specific comments related to studies published 

since they adopted the RfD for perchlorate. ASDWA does not have any additional research to offer 

and simply suggests that EPA review the available, peer reviewed, scientific data. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 244 of 1099

Response: EPA will continue to evaluate the available science related to perchlorate as the Agency 

makes a regulatory determination for perchlorate. 

Commenter Name: Jonathan Borak 

Commenter Organization: Yale School of Medicine 

EPA Document ID: EPA-HQ-OW-2009-0297-0209 

EPA Comment ID: 28510 

EPA Comment Code: 2500 

Comment: Blount et al. and Steinmaus et al. adopted the 100 ug/L level for their studies because it 

is the WHO/UNICEF/ICIDD criterion for iodine sufficiency (16). However, that level has been 

recommended as a benchmark for evaluating the median spot urinary iodine level of populations; it 

has not been advocated for determining iodine sufficiency in individuals. It is not a useful 

benchmark for individuals because, as described below, individuals demonstrate significant 

variability of urinary iodine. Many individuals with sufficient iodine intake have spot urine levels 

<100 ug/L level from time to time. 

Urinary iodine levels generally reflect dietary iodine intake over the prior 12-24 hour period, with 

peaks occurring about 8-12 hours after major meals, thus variations in day-to-day diet can lead to 

marked day-to-day variations in spot urine iodine (17). Significant day-to-day variations have also 

been documented in subjects with controlled dietary iodine intake. 

For example, six adults studied for 30 days at the NIH Clinical Center were given a diet that 

provided a constant daily iodine intake (18). Following a six- day stabilization period, daily 24-hour 

urine specimens were collected for iodine measurements. Day-to-day coefficients of variation (CV) 

for 24-hour iodine excretion were calculated for each of two successive 12-day periods. Among 

individual subjects, CVs ranged from 7%-24.1%. Thus, even under controlled conditions, constant 

diet and 24-hour urine collection, there was substantial day-to-day variability of iodine excretion. 

Greater variability was seen in studies that did not restrict subjects' diets and iodine intake. 

Rasmussen et al. measured iodine levels in 24-hour urine samples collected on four consecutive days 

from each of ten subjects whose diets and iodine intake were not controlled. For individuals, day-today urinary iodine levels varied up to three-fold (19). 

Burgi et al. collected morning urine samples from eleven subjects on 21 consecutive days. Diets and 

iodine intake were not controlled. For individuals, day-to-day CVs ranged from 15%-75%; the 

average day-to-day CV for the group was 39%. Results from individual subjects demonstrated hectic 

day-to-day variability (20). 

Andersen et al. measured urinary iodine in 15 men sampled monthly for 12 months. Diets and 

iodine intake were not controlled. Twelve-month averaged urine levels for individuals ranged from 

29-81 mg/L, but individual monthly urine levels ranged from 10-260 mg/L. The CVs calculated for 

each subject's 12 monthly samples ranged from 20.1%-70.5 % (21). 

In addition, urinary iodine excretion follows diurnal and seasonal cycles. Higher urine iodine levels 

are generally found in morning samples and wintertime samples (17). 
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Because of such day-to-day variations in urine iodine excretion, studies that consider only isolated 

spot urine levels report significantly greater dispersion of individual urine levels than do studies 

which average urine levels over time. In other words, isolated spot urinary iodine levels are imprecise 

reflections of an individual's iodine sufficiency. 

More generally, isolated urinary iodine levels provide little useful information about the long-term 

iodine nutrition of an individual. For example, consider the views of the National Academy of 

Clinical Biochemists (17): 

"In most circumstances the determination of urine iodine provides little useful information on the 

long-term iodine status of an individual, since the results obtained merely reflect recent dietary 

iodine uptake." 

For such reasons, dividing a population into two groups solely on the basis of a single spot urinary 

iodine level, as in the Blount and Steinmaus studies, will almost certainly lead to significant exposure 

misclassification. Blount et al. and Steinmaus et al. recognized that possibility, but argued that such 

misclassification would be "random error (not bias)" and thus "nondifferential and therefore likely 

to bias estimates of association toward the null, not toward the positive effects" (14). That statistical 

argument is valid for nondifferential misclassification of binary exposure categories, but it is not 

necessarily valid for more complex sorts of misclassifications: 

"Contrary to popular misconceptions, however, nondifferential exposure or disease misclassification 

can sometimes produce bias away from the null." (22) 

The Blount et al. study classified individuals based on single spot urine levels of iodine and 

perchlorate; Steinmaus et al. also included a spot urine level for thiocyanate. Misclassifications would 

not have been simple and binary. Still greater complexity and potential bias arise from the fact that 

day-to-day variations of iodine and perchlorate intake do not vary randomly from each other. For 

example, the FDA Total Diet Study (23) documents that some food groups (e.g., dairy) are major 

sources of both iodine and perchlorate, while others (e.g., grains, vegetables) are rich in only one or 

the other. Thus, day- to-day dietary variations may result in either strongly positive or strongly 

negative associations between these two anions. In any event, their relationship is unlikely to be 

random. Further complicating analytical assessment and interpretations is the fact that iodine and 

perchlorate have different serum half-lives and different urinary excretion rates (11,12). 

It is not reasonable to minimize the importance of such misclassification by reliance on "popular 

misconceptions". Even more complex misclassification bias and confounding can be expected when 

other 'NIS stressors' (e.g., thiocyanate and nitrate) are measured in isolated spot urines and included 

in the analysis. For such reasons, cross-sectional data based on isolated spot urine samples must be 

used with caution when inferring causation and estimating the magnitude of potential interactions. 

For the same reasons, isolated spot urine levels should not be used to characterize the proportion of 

a population deemed "iodine deficient"; doing so will overestimate the number of "deficient" 

individuals. That concern was also expressed by the NAS Committee to Assess the Health 

Implications of Perchlorate Ingestion ("NAS Committee") (24): 
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"... the distribution of iodide values measured in spot urine samples is broader than values measured 

repeatedly in individual subjects (21); this leads to overestimation of the number of subjects with 

both low and high values." 

The NAS Committee also raised concerns about the over-interpretation of NHANES spot urine 

iodine data to suggest that significant numbers of young adults (including pregnant women) had 

significant iodine deficiency because their spot urine levels were <100 ug/L (24) 

"Furthermore, among people 15-44 years old, including pregnant women, there were no differences 

in serum TSH and T4 concentrations between those with urinary iodide values less than 50 ug/L 

and those with higher values (25); apparently, the iodide intake in the former group was not low 

enough to cause a fall in T4 secretion." 

In reviewing these concerns, the OIG concluded that there was "significant uncertainty" when 

NHANES data for isolated spot urinary iodine were used as the basis for determining iodine 

sufficiency in pregnant women: 

"these results do represent a significant uncertainty in the science concerning this public health issue 

(i.e., what portion of the U.S. pregnant women population are moderately or mildly iodide 

deficient?)." (13) 

In summary, use of simultaneous measurements of iodine, perchlorate and other NIS stressors in 

isolated spot urine samples to characterize cross-sectional populations can be expected to result in 

significant misclassification that may bias associations toward or away from the null. Likewise, they 

are likely to overestimate the numbers of individuals at the extremes of the population distribution. 

Analytical findings and population characterizations based on such testing are likely to introduce 

significant uncertainty in regulatory determinations that rely upon them. 

Thank you for this opportunity to comment upon and contribute to your regulatory determination 

for perchlorate. 

Yours truly, Jonathan Borak, MD, DABT, FACP, FACOEM Clinical Professor of Epidemiology 

and Medicine Yale School of Medicine 

References 

1. Blount BC, Pirkle JL, Osterloh JD, et al.: Urinary perchlorate and thyroid hormone levels in 

adolescent and adult men and women living in the United States. Environ Health Perspect 

114:1865-1871, 2006. 

2. Wolff J: Perchlorate and the thyroid gland. Pharmacol Rev 50:89-105, 1998. 

3. Van Sande J, Massart C, Beauwens R, et al.: Anion selectivity by the sodium iodide symporter. 

Endocrinology 144:247-252, 2003. 

4. Eskandari S, Loo DDF, Dai G, et al.: Thyroid Na+/I- Symporter. J Biol Chem 272:27230-27238, 

1997. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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5. De La Vieja A, Dohan O, Levy O, et al.: Molecular analysis of the sodium/iodide symporter: 

Impact on thyroid and extrathyroid pathophysiology. Physiol Rev 80:1083-1105, 2000. 

6. Wyngaarden JB, Wright BM, Ways P: The effect of certain anions upon the accumulation and 

retention of iodide by the thyroid gland. Endocrinology 50:537¬549, 1952. 

7. Wyngaarden JB, Stanbury JB, Rapp B: The effects of iodide, perchlorate, thiocyanate and nitrate 

administration upon the iodide concentrating mechanism of the rat thyroid. Endocrinology 52:568-

574, 1953. 

8. Alexander WD, Wolff J: Thyroidal iodide transport VIII. Relationship between transport 

goitrogenic and antigoitrogenic properties of certain anions. Endocrinology 78:581-590, 1966. 

9. Greer MA, Stott AK, Milne KA: Effect of thiocyanate, perchlorate and other anions on thyroidal 

iodine metabolism. Endocrinology 79:237-247, 1966. 

10. Tonacchera M, Agretti P, Ceccarini G, et al.: Autoantibodies from patients with autoimmune 

thyroid disease do not interfere with the activity of the human iodide symporter gene stably 

transfected in CHO cells. Eur J Endocrinol 144:611-618, 2001. 

11. Tonacchera M, Pinchera A, Dimida A, et al.: Relative potencies and additivity of perchlorate, 

thiocyanate, nitrate, and iodide on the inhibition of radioactive iodide uptake by the human sodium 

iodide symporter. Thyroid 14:1012-1019, 2004. 

12. De Groef B, Decallonne BR, Van der Geyten S, et al.: Perchlorate versus other environmental 

sodium/iodide symporter inhibitors: potential thyroid- related health effects. Eur J Endocrinol 

155:17-25, 2006. 

13. Office of Inspector General: Scientific Analysis of Perchlorate (Assignment No. 2008-0010) (at: 

http://www.epa.gov/oig/reports/perchlorate.htm). Washington, DC: U.S. Environmental 

Protection Agency, 2008. 

14. Steinmaus C, Miller MD, Howd R: Impact of smoking and thiocyanate on perchlorate and 

thyroid hormone associations in the 2001-2002 National Health and Nutrition Examination Survey. 

Environ Health Perspect 115:1333-1338, 2007. 

15. US Food and Drug Administration: 2004-2005 Exploratory Survey Data on Perchlorate in Food 

(at: http://www.fda.gov/Food/FoodSafety/FoodContaminantsAdulteration/ChemicalCo 

ntaminants/Perchlorate/ucm077685.htm). 2009. 

16. WHO/UNICEF/ICCIDD: Assessment of Iodine Deficiency Disorders and Monitoring their 

Elimination (WHO/NHD/01.1). Geneva: World Health Organization, 2001. 

17. Demers LM, Spencer CA: Laboratory Medicine Practice Guidelines: Laboratory Support for the 

Diagnosis of Thyroid Diseases (at: 

http://www.aacc.org/members/nacb/Archive/LMPG/ThyroidDisease/Pages/Thyroid 

DiseasePDF.aspx). Washington, DC: National Academy of Clinical Biochemistry, 2002. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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18. Vought RL, London WT, Lutwak L, et al.: Reliability of estimates of scrum inorganic iodine and 

daily fecal and urinary iodine excretion from single casual specimens. J Clin Endocrinol 23:1218-

1228, 1963. 

19. Rasmussen LB, Ovesen L, Christiansen E: Day-to-day and within-day variation in urinary iodine 

excretion. Eur J Clin Nutr 53:401-407, 1999. 

20. Burgi H, Bangerter B, Siebenhuner L: High day-to-day variability of urinary iodine excretion 

despite almost universal salt iodization in Switzerland. In: Geertman RM (ed): 8th World Salt 

Symposium, Amsterdam: Elsevier Publishers, pp. 961-963, 2000. 

21. Andersen S, Pedersen KM, Pedersen IB, et al.: Variations in urinary iodine excretion and thyroid 

function. A 1-year study in healthy men. Eur J Endocrinol 144:461-465, 2001. 

22. Rothman KJ, Greenland S: Modem Epidemiology. Philadelphia: Lippincott-Raven Publishers, 

76-78, 1998. 

23. Murray CW, Egan SK, Kim H, et al.: US Food and Drug Administration's total diet study: 

Dietary intake of perchlorate and iodine. J Exp Sci Environ Epidemiol 18:1- 10, 2008. 

24. National Academy of Sciences: Committee to Assess the Health Implications of Perchlorate 

Ingestion. (available at http://vvww4.nas.eduAvebcr.nsf/ProjectScopeDisplay/BEST-K-03-05- 

A?OpenDocument). Washington DC: National Academies Press, 2003. 

25. Soldin OP, Tractenberg RE, Pezzullo JC: Do thyroxine and thyroid-stimulating hormone levels 

reflect urinary iodine concentrations? Ther Drug Monit 27:178-185, 2005. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Shannon Cunniff 

Commenter Organization: Department of Defense (DOD) 

EPA Document ID: EPA-HQ-OW-2009-0297-0411 

EPA Comment ID: 28529 

EPA Comment Code: 2500 

Comment: Comment No. 16 
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Section IV. Consideration of Studies Published Since EPA Adopted the NAS RfD for Perchlorate 

Page & Paragraph Page 41891 

Comment We would like to call to EPA's attention the new data from the Cao, et al. 2009 

perchlorate, thiocyanate, and nitrate manuscript developed in collaboration with the CDC, which the 

authors believe is the first study of its kind. Individual thyroid function and perchlorate, thiocyanate, 

and nitrate exposure were directly measured in about 50 infants born at the Children's Hospital of 

Philadelphia, the Hospital of the University of Pennsylvania, and affiliated clinics, in a study 

conducted in 2004-2005 where ninety-two full term infants between birth and 1 year of age 

participated. 

In general, the authors' draft manuscript states that associations between TSH and thiocyanate were 

larger than those between TSH and perchlorate and nitrate. Also, a mixed linear model (one 

goitrogen exposure at a time) showed that the three goitrogens all had significantly positive 

associations with TSH and T4. The average urinary thiocyanate level in these infants was almost 50 

times higher than average perchlorate level, and thiocyanate was more strongly related to TSH than 

perchlorate. With all three [goitrogens] modeled simultaneously, all children with higher nitrate and 

thiocyanate had higher TSH, but higher perchlorate was significant only in children with low iodide. 

Suggested Action, Revision and References (if necessary) As EPA continues to evaluate new 

perchlorate data as stated in the FR announcement this study should be a relevant consideration. 

Category* O 

 Comment No. 17 

Section IV. Consideration of Studies Published Since EPA Adopted the NAS RfD for Perchlorate 

Page & Paragraph Page 41891 

Comment The recent publication describing a model by M. Lorber entitled, "Use of a simple 

pharmacokinetic model to characterize exposure to perchlorate," Journal of Exposure Science and 

Environmental Epidemiology (2009) 19, 260-273 was not cited by EPA when evaluating perchlorate 

modeling alternatives. According to the author: 

The primary benefit of these simple models is that they allow for an expanded study of the 

magnitude and patterns of external exposure. This is a different emphasis than the complex, PBPK 

models, which are used more to study the internal fate (e.g., dose-to-target organs) and potential 

health effects of contaminants to which an individual is exposed. ...In short, these simple models are 

allowing for an expanded and more valid study of external patterns of exposure. 

Suggested Action, Revision and References (if necessary) The EPA "in-house" model developed by 

M. Lorber should be given consideration as appropriate. 

Category* S 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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 Comment No. 18 

Section V. Next Steps 

Page & Paragraph Page 41892 

Comment Although EPA indicates that no additional research is needed to make a regulatory 

decision, Blount et al. (2009), the USEPA OIG perchlorate document (December, 2008), and others 

have stated that perchlorate, thiocyanate and nitrate from dietary exposure, coupled with low iodine 

intake merits further research. 

Suggested Action, Revision and References (if necessary) We do not want to delay the regulatory 

process, but encourage further research in these areas to decrease uncertainty associated with 

perchlorate cumulative risk assessment. 

Category* S 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: John P Gibbs 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0636 

EPA Comment ID: 28551 

EPA Comment Code: 2500 

Comment: 2) MORE RECENT STUDIES 

Subsequent to the NAS report, Braverman et al 2005 demonstrated the same dose response as Greer 

for iodine uptake inhibition, among workers with long term perchlorate exposure. There were no 

demonstrable adverse thyroid effects among the workers in this study or in a previous study at the 

same location (Lamm et al 1999). Benchmark calculations (Crump & Gibbs 2005) were performed 

on the data from these two studies as well as with data from the Greer study. The lower 95% 

statistical confidence limits on benchmark doses estimated from a combined analysis of the two 

occupational studies ranged from 0.21 to 0.56 mg/kg-day for free T4 index and from 0.36 to 0.92 

mg/kg-day for TSH. Corresponding estimates from the short-term clinical study were within these 

ranges. 
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Tellez et al 2005 conducted an epidemiological study among pregnant women in Chile and found no 

impact of perchlorate on maternal thyroid function during pregnancy or on infants at birth. Water 

perchlorate concentrations ranged from 4ppb to over 100 ppb. Amitai et al 2007 studied neonatal 

T4 in a region of Israel where perchlorate contamination was found in the public water supply at 

concentrations far in excess of those documented in the U.S. This study finds no change in neonatal 

T(4) levels despite maternal consumption of drinking water that contains perchlorate at levels in 

excess of the Environmental Protection Agency (EPA) drinking water equivalent level (24.5 

microg/L). Therefore the perchlorate RfD is likely to be protective of thyroid function in neonates 

of mothers with adequate iodide intake. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Kay Brothers 

Commenter Organization: Southern Nevada Water Authority 

EPA Document ID: EPA-HQ-OW-2009-0297-0667 

EPA Comment ID: 28699 

EPA Comment Code: 2500 

Comment: Again, we certainly appreciate the need for modeling when sufficient empirical data do 

not exist. However, in the case of perchlorate, significant peer- reviewed literature is available that 

should be considered by EPA before relying on less certain modeling to generate HRLs. Response: 

EPA acknowledges and thanks you for providing comments. EPA will continue to evaluate the 

available science related to perchlorate. On August 19, 2009, EPA published a Federal Register 

notice requesting supplemental public comments on its preliminary determination not to regulate 

perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 41883). In this August 19, 2009 

Federal Register notice, EPA requested comments on additional interpretation of data on the level 

of human health concern, perchlorate frequency of occurrence in drinking water, and the 

opportunity for health risk reduction through a national primary drinking water standard, to help 

determine if it should be regulated. EPA considers both the extent of national occurrence and the 

severity of health effects for a contaminant, as well as other factors (e.g., sources of exposure), when 

deciding whether regulation presents a meaningful opportunity for health risk reduction. Therefore, 

the Agency considered national occurrence and the severity of health effects from perchlorate and 

concluded that regulation was warranted, so EPA has determined that perchlorate will be regulated. 

Commenter Name: Tom Porta 
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Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 28749 

EPA Comment Code: 2500 

Comment: Subject: Docket ID No. EPA-HQ-OW-0297 

Reference: Drinking Water: Perchlorate Supplemental Request for Comments (Federal Register / 

Vol. 74, No. 159 / Wednesday, August 19, 2009 / Notices 

The Nevada Division of Environmental Protection (NDEP) provides herein, comments to assist the 

US Environmental Protection Agency (EPA) in their evaluation of the benefits of establishing a 

national primary drinking water rule for perchlorate. The EPA is evaluating whether establishing this 

rule would provide a significant reduction in human health risk by reducing exposure to perchlorate 

in drinking water. In that context, NDEP comments are provided in response to an August 19, 2009 

notice within the Federal Register entitled "Drinking Water: Perchlorate Supplemental Request for 

Comments", Docket ID No. EPA-HQ- OW-2009-0297. 

Comments are arranged in the order presented within the above-referenced Federal Register Notice 

(Notice). The numerical designation follows that used in the Notice. The attached appendices 

provide supporting information, along with a reference to guide the reader to specific supporting 

information. These references provide examples, describe assumptions, and enhance the clarity of 

the comments. Applicable references are cited throughout the text and appendices, and are listed at 

the end of this document. 

III. Alternative Approaches to Analyzing Scientific Data Related to Perchlorate in Drinking Water: 

A. Interpretation of the Physiologically-Based Pharmacokinetic (PBPK) Modeling 4. Request for 

Comment on Alternative Approaches a. EPA requests comment on using the PBPK model to 

evaluate the relative sensitivity of various life stages to perchlorate exposure in drinking water. 

Comment A.4.a.1: It is inappropriate to use the PBPK model to support a regulatory action because 

the underlying scientific evidence indicating sensitivity of the fetus and/or neonate is lacking. 

Additional clinical data are needed to help refine the PBPK model. Data are needed for adults, 

including pregnant women, and for neonates concerning thyroidal iodine capacity and the effects of 

sodium-iodide symporter (NIS) upregulation on thyroidal iodine uptake and/or thyroxine levels. 

Also, additional studies of other adults are needed to evaluate the effects of temporary iodine 

deficiency and NIS upregulation on perchlorate competitive inhibition of thyroidal iodine uptake 

and/or free thyroid hormone levels. This additional research would provide useful data to consider 

in further refining the PBPK model to accurately reflect the effects of iodine deficiency in pregnant 

women, fetuses and neonates. If the additional clinical data support concerns for relative sensitivity 

of the fetus and neonate, then a refined and validated PBPK model would be useful. 

Comment A.4.a.2: Perchlorate is known to be well absorbed into the human body, and at sufficient 

doses can act as an inhibitor of iodine uptake into the thyroid due to competition with iodine for the 

sodium-iodide symporter (NIS) (NRC, 2005). Although this competitive inhibition of NIS is not an 

adverse health effect, it is apparently the first step in a cascade of events that ultimately reduces the 

production or release of thyroxine from the thyroid gland into the bloodstream by depleting stored 
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iodine in the thyroid. However, humans have multiple and redundant mechanisms for maintaining 

adequate amounts of free thyroid hormones (free thyroxine (FT4) and the active hormone receptorbinding agent, free tri-iodothyronine (FT3)) when diet or environmental agents cause interruption of 

thyroidal iodine intake or in circulating active hormone levels (Moore, 1984; Moulopoulis et al., 

1988). Some of the most prominent homeostatic mechanisms for maintaining adequate levels of 

circulating FT3 in humans include: 

1. NIS upregulation capacity to rapidly (within hours) increase thyroidal iodine uptake; 2. 

Organification of iodide within the thyroid into thyroglobulin, a protein containing bound T4 

subunits that act as a storage pool within the thyroid; 3. Thyroid stimulating hormone (TSH) 

secretion and thyrotropin releasing hormone (TRH) secretion triggered by various stressors (e.g., 

cold or fever) or by lowered FT3 in circulation, leading to increased production and secretion of T4 

and T3 into the bloodstream; 4. Hypertrophy and/or increase number and volume of thyroid 

follicular cells (including induction of goiter) with long-sustained TSH stimulation typically from 

FT3 shortage in circulation; 5. Modulation of thyroid binding globulin (TBG) content in the 

circulation which alters the storage capacity and free vs. bound hormone balance in the circulation; 

6. Modulation of iodide and thyroid hormone excretion via the kidneys, feces, and/or metabolic 

breakdown of hormones; and 7. Modulation of thyroid function and thyroid hormone distribution 

by estrogens, human chorionic gonadotropin, leutinizing hormone, and other hormones during 

pregnancy and lactation. 

The human body is recognized to maintain a sensitive and dynamic balance between TSH and FT3, 

and the thyroid injuries or diseases that significantly alter this dynamic balance (in magnitude and/or 

duration) have the most clinical importance with respect to thyrotoxicity and adverse health 

consequences (Moore, 1984; Moulopoulis et al., 1988). 

The homeostatic mechanism perhaps most relevant to perchlorate thyrotoxicity in humans and 

other mammals is the upregulation of NIS when dietary iodine is sufficiently low for an extended 

period such that thyroidal iodine stores become depleted. Such upregulation of thyroidal NIS leads 

to an increased number of NIS sites on thyroid follicle cells, which in turn has the impact of 

increasing iodine uptake and reducing the impact of competitive inhibition by perchlorate and other 

chemicals with NIS binding capacity such as nitrate, thiocyanate, and bromate. At relatively high 

doses of NIS competitive inhibitor agents in humans, the most immediate response is NIS 

upregulation, which restores thyroidal iodine uptake and reduces the effects of most environmental 

doses of exogenous NIS inhibitors. 

The available evidence in studies of rats subjected to subchronic doses of perchlorate indicates solely 

reversible thyroid effects in perchlorate-treated adults and an important role of homeostatic 

mechanisms (e.g., NIS upregulation) in effects noted at doses (e.g., 1,000 ug/kg-day) more than 

1000-fold higher than the perchlorate reference dose. Paulus et al. (2007) demonstrated that longterm iodine deficiency in rats leads to upregulation of NIS and increased resistance to as much as 5.6 

mg/kg-day perchlorate inhibition of thyroidal iodine uptake. The highest dose of 28 mg/kg-day was 

reported to overwhelm the NIS upregulation in iodine deficient rats, leading to reduced thyroxine 

levels and corresponding TSH perturbations. Paulus et al. (2007) noted: 

"The iodine-deficient animals in this study absorbed twice as much of an administered dose of 1311 

into the thyroid as the iodine-sufficient animals (see Table 2). This increase in absorption by the 

animals on the iodine-deficient diet clearly outweighed other factors affecting absorption. This 
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increase in absorption is presumably preceded by elevation in release of TSH via the hypothalamuspituitary-thyroid (HPT) axis, in response to low levels of thyroid hormone. It is known that 

upregulation of the thyroid by TSH is accompanied by increased expression of NIS (Kogai et al., 

1997). Thus, nutritional deficiency in iodine induces the thyroid NIS system to be upregulated, 

increasing the population of NIS on the surface of the follicular cells. The time required for changes 

in T3, T4, and TSH in response to nutritional deficiency in iodine vary within species and nutritional 

states but it is known that changes in concentration of the NIS occur rapidly (within hours) in 

response to changes in the level of TSH (Eng et al.,1999; Yu et al., 2002). It is now understood that 

this upregulation occurs as a response to iodine deficiency, perhaps even in the absence of increases 

in TSH (Johnston et al., 2005). Moreover, during pregnancy, upregulation occurs both by rises in 

thyroid-stimulating hormone (TSH) and in response to higher titers of the hormone human 

chorionic gonadotropin (Glinoer, 1997). It is proposed that changes in NIS populations occur 

rapidly (within hours) and that this is the salient mechanism for control of iodine concentrations in 

the thyroid (Eng et al., 1999). 

Analyses of the results of this study indicate that a second effect of this upregulation is that the NIS 

system becomes much more refractory to inhibition of iodide uptake by perchlorate ion. [...I]n order 

to restrict normal transport of iodide, a greater fraction of a larger population of NIS would need to 

be blocked, and this would require a higher concentration of perchlorate." 

Yu et al. (2002) identified similar NIS upregulation that compensated for 0.1 to 3 mg/kg-day 

perchlorate in euthyroid rats; the highest dose of 10 mg/kg-day was reported to overwhelm the NIS 

upregulation in euthyroid rats, leading to reduced thyroxin levels and corresponding TSH 

perturbations. Yu et al. (2002) noted: 

"In the present study, the up-regulated thyroid, under the influence of TSH, was able to overcome 

the blocking effects of perchlorate by increasing its capacity to sequester iodide and produce 

hormones. This is clearly a dose-dependent phenomenon, which was overwhelmed by the blocking 

effects of high serum levels of perchlorate. [] 

A 90-day rat study of ammonium perchlorate identified reversible thyroid hormone perturbations at 

doses of up to 1,000 mg/kg-day without effects on thyroid weight or histopathology or any effects 

on sperm parameters, estrous cycle, bone marrow, or serum hormones; the highest dose of 10 

mg/kg did increase thyroid weight and follicular cell hypertrophy (Siglin et al., 2000). Thus, it 

appears that NIS upregulation in the face of iodine deficiency increases the number of thyroidal 

receptors, thereby diluting impacts of low (< 100 ug/kg-day) to moderate (< 1,000 ug/kg-day) doses 

of perchlorate on reversible inhibition of thyroidal iodide uptake." 

Consistent with the above observations in rats, long-term iodine deficiency in humans is known to 

rapidly induce NIS upregulation that enhances iodine uptake from the diet and leads to TSH release 

to maintain circulating thyroxine levels (Andersen et al., 2001). Short-term and relatively mild iodine 

deficiency also leads to NIS upregulation coincident with normal thyroxine levels and slightly 

decreased TSH release due to increased sensitivity of thyrocytes and a greater number of thyrocytes 

participating in thyroid function (Brabant et al., 1992). Brabant et al. (1992) administered 900 

mg/day (about 13 mg/kg-day in 3 divided doses) of perchlorate for 4 weeks in healthy male subjects 

in order to induce a short-term, mildly iodine-deficient state, which corresponded to an estimated 

25% depletion in thyroidal iodine capacity. This high exposure regimen led to nominal changes in 

free thyroxine and near doubling of circulating thyroglobulin, the latter which may also represent an 
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adaptive response to iodine deficiency providing a greater thyroxine capacity in the form of 

thyroglobulin in the blood (Brabant et al., 1992). 

Perchlorate has been used as a pharmaceutical agent in persons with abnormally high thyroxine 

production such as in Grave's Disease, with sufficiently high regular dosages (e.g., 6,000 to 28,000 

ug/kg-day) resulting in reduction of circulating FT3 and FT4 levels to limit the availability of 

thyroidal iodide via NIS inhibition. However, lower doses in humans administered orally for several 

days to 6 months do not appear to significantly impact circulating levels FT3 or FT4 or TSH, or to 

change thyroid size, despite the demonstration of reduced efficiency (percentage of radioactive 

iodine uptake) of thyroidal iodide uptake (Lawrence et al, 2000, 2001; Greer et al., 2002; Braverman 

et al., 2006; Braverman, 2009). Also, studies of occupational and environmental perchlorate 

exposures have failed to reveal any significant impact on thyroid function at doses that in some cases 

greatly exceed the currently proposed reference dose of 0.7 ug/kg-day by more than 100-fold 

(Amitai et al., 2007; Tellez et al., 2005; Gibbs et al., 1998; Li et al., 2000a,b, 2001; Lamm et al., 1999; 

Braverman et al., 2005, 2006; Braverman, 2009; Gibbs and Landingham, 2008; Kelsh et al., 2003; 

Huffier et al., 2006; Chang et al. 2003; Crump et al., 2000; Gibbs et al., 2004; Leung et al., 2009; 

Pearce et al., 2007a,b). 

With respect to sensitivity of the neonate life stage, Ginsberg et al. (2007) have argued that a 

combination of factors may put infants at greater risk, particularly during lactation. Because the 

breast is one of the extrathyroidal tissues known to express NIS, these researchers expressed the 

concern for potential adverse effects on neonatal growth and development due to the combination 

of possible iodine deficiency and possible accumulation of perchlorate (and depletion of iodide) in 

breast milk. Kirk et al. (2005) reported on iodide and perchlorate levels in dairy and breast milk in 

the United States and observed a linear correlation between increasing perchlorate and decreasing 

iodide among 36 human breast milk samples (perchlorate concentrations ranged from 0.6 to 92.2 

ug/L, mean 10.5 ug/L; iodide concentrations ranged from 4.5 to 184.5 ug/L, mean 63.3 ug/L. 

However, the reported high correlation (r2 > 0.9) was based on only six breast milk samples with 

perchlorate levels over 10 ug/L (Kirk et al., 2005). Larger studies of iodine and perchlorate levels in 

breast milk (Pearce et al., 2007b) and colostrum (Leung et al., 2009) in Boston- area women reported 

no correlation of perchlorate to iodine in the mother's milk (including colostrum) or in urine. 

With respect to sensitivity of the fetus life stage, pregnant females and their offspring in the fetal and 

neonatal stages, if thyroid deficient, have been postulated as being vulnerable to perchlorate toxicity 

to the thyroid, although this has not been demonstrated to date in human populations (Braverman, 

2009). The available scientific studies do not point to increased prevalence of cretinism, maternal 

goiter, or neonatal hypothyroidism in the general U.S. population or in small populations with 

perchlorate in public water supplies (Amitai et at 2007; Leung et at 2009; Li et al., 2000, 2001; 

Buffler et al., 2006; Crump et al 2000; Kelsh et al., 2003; Gibbs et al., 2004; Chang et al., 2003). 

McLanahan et al. (2009) reported a biologically-based dose-response model of the HPT axis coupled 

with a physiologically-based pharmacokinetic model of perchlorate in rats and concluded that 

perchlorate may have two modes of action: one involving inhibition of NIS and a second involving 

reduced production/release of thyroxine from the thyroid. They pointed to findings of Yu et al. 

(2002) who noted: 

"Recovery of serum thyroid hormones from the blocking effect of the 1.0 and 3.0 mg/kg-day doses 

of perchlorate lagged behind the TSH induced up-regulation in thyroidal uptake of 125I. A TSH-
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induced "iodide sufficient" condition was evident in the thyroid; however, serum thyroid hormones 

were persistently low for days. The reason for this is unknown but suggests that, at high doses of 

perchlorate that may initially saturate the symporter, perchlorate may cause secondary effects on the 

thyroid beyond competitive inhibition of thyroidal uptake of iodide." 

However, rats are recognized to have considerably lower iodine storage capacity in the thyroid and 

hence may be expected to exhibit perturbations in circulating thyroxine and TSH more readily than 

would be expected in humans. McLanahan et al. (2009) also pointed to earlier studies indicating 

perchlorate may displace iodide on certain binding proteins at very high concentrations in vitro 

(Okabe and Hokaze, 1993; Yamada, 1967), and to recent reports that perchlorate is probably 

concentrated in thyroid cells at high doses (Tran et al., 2008; Dohan et al., 2007). McLanahan et al. 

(2009) concluded that, 

"A significant correlation of effects of ClO4- with serum thyroid hormones in humans has yet to he 

confirmed, so the importance of this potential mode of [mode of action] in humans is not known." 

Moreover, the observed high dose effects on protein binding and on accumulation of perchlorate in 

the thyroid are reversible and not likely to be relevant to environmental perchlorate exposure levels 

in humans and are not associated with thyroid pathology at moderate dosages (e.g., 100-1,000 

ug/kg-day) in normal and iodine-deficient rats based on detailed assessments (Paulus et at, 2007; Yu 

et al., 2002; Siglin et al., 2000). 

In regards to sensitivity of different life stages to perchlorate thyrotoxicity, research is needed to 

examine the nature and extent of NIS upregulation in iodine deficient newborns and neonates, as 

well as assessment of the natural capacity of thyroidal iodine stores at birth to buffer any impacts on 

circulating thyroxine when iodine intake is relatively low or intermittent. It is generally known that 

thyroid deficiency leads to NIS upregulation (and increased thyroid volume) in pregnant and 

nonpregnant adults as well as in neonates, although the capacity of this protective mechanism is not 

well characterized in pregnant women or neonates. Consistent with the expected presence of NIS 

upregulation in mothers and infants, the available scientific studies do not point to increased 

prevalence of cretinism, maternal goiter, or neonatal hypothyroidism in the general U.S. population 

or in populations with higher perchlorate levels in public water supplies (Amitai et al., 2007; Leung 

et al., 2009; Li et al., 2000, 2001; Buffler et al., 2006; Crump et al., 2000; Kelsh et al., 2003; Gibbs et 

al., 2004; Chang et al., 2003). 

In summary, although high doses of perchlorate 1,000 ug/kg-day) for extended time periods can 

cause reversible perturbations in thyroid function, such impacts have not yet been demonstrated at 

moderate doses (< 100 ug/kg-day) or the relatively low environmental doses (< 10 ug/kg-day) likely 

to be relevant to drinking water exposures. These findings, largely in human studies, suggest that the 

EPA-adopted reference dose of 0.7 ug/kg-day is a conservative and health- protective reference 

dose that incorporates a 10-fold uncertainty factor applied to the point of departure (7 ug/kg-day) to 

account for differences between healthy adults and the most sensitive population: fetuses of 

pregnant women who might have hypothyroidism or iodide deficiency. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28806 

EPA Comment Code: 2500 

Comment: Data shows that perchlorate is actively transported into mammary epithelial cells by the 

sodium iodide symporter (NIS), resulting in an accumulation of perchlorate in breast milk.[FN47: 

Dohan, O, C Portulano, C. Basquin, A Reyna- Noyra, LM Amzel, and N Carrasco. 2007. The 

Na+/I- symporter (NIS) mediates electroneutral active transport of the environmental pollutant 

perchlorate. PNAS 104(51):20250-20255.][FN48: Dasgupta, P. K., Kirk, A. B., Dyke, J. V., and 

Ohira, S.-I. (2008). Intake of Iodine and Perchlorate and Excretion in Human Milk. Environ. Sci. 

Technol. 42, 8115-8121.] These data suggest that perchlorate may not only inhibit iodide 

accumulation in maternal milk but also would be transferred in breast milk to the nursing infant 

where it would be predicted to inhibit iodide uptake in the infant's thyroid gland. The NIS also is 

found in the placenta and based on this new research it seems likely that perchlorate is actively 

transported across the placenta. Because the fetus and developing infant require adequate iodide for 

thyroid hormone function, any determination of a safe level of exposure to perchlorate should take 

into account this mode of action for perchlorate toxicity. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28807 
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EPA Comment Code: 2500 

Comment: c. On the most appropriate data to estimate alternative HRLs 

NRDC response: The CDC (2006/2007) data represent the best available data. 

The derivation of a health-based standard for perchlorate should reflect the best available data, 

including published data collected and analyzed by the CDC and described by Blount et al (2006) 

and Blount et al (2007).[FN49: Blount BC, Valentin-Blasini L, Osterloh JD, Mauldin JP, Pirkle JL. 

Perchlorate exposure of the US Population, 2001-2002. J Expo Sci Environ Epidemiol. 2007 

Jul;17(4):400-7. Epub 2006 Oct 18. Blount BC, Pirkle JL, Osterloh JD, Valentin- Blasini L, Caldwell 

KL. Urinary perchlorate and thyroid hormone levels in adolescent and adult men and women living 

in the United States. Environ Health Perspect. 2006 Dec;114(12):1865-71.] The CDC data have the 

following significant advantages over the Greer et al data used by EPA: 

1. Although the CDC data are from a cross-sectional analysis, because the survey includes a large 

number of individuals, the variability represents random error, not bias, and the data are likely to be 

representative of chronic perchlorate exposure; 2. The number of individuals included in the CDC 

study are sufficient for the specific analysis of a sensitive subpopulation defined as women with low 

iodine intake; 3. A benchmark dose (BMD) analysis of perchlorate-related modulation of serum 

thyroid hormone concentrations is feasible; and 4. Perchlorate exposures, as measured by urinary 

perchlorate concentration, corresponding to the benchmark dose low (BMDL) can be converted to 

an estimated dose in mg/kg-day, that can be used as the point of departure for the derivation of 

both the MCL and HRL. 

From Blount et al (2006) we know that the mean for total serum T4 concentrations in women is 

8.27 ug/dL and the 25th percentile of perchlorate exposure (equivalent to 1.6 ppb perchlorate in 

urine) is associated with a 10% drop in total serum T4 in women with low iodine intake.[FN50: 

Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell KL. Urinary perchlorate and thyroid 

hormone levels in adolescent and adult men and women living in the United States. Environ Health 

Perspect. 2006 Dec;114(12):1865-71.] Importantly, the unique physiology of pregnancy and 

interactions between the mother and fetus make both especially susceptible to the harmful effects of 

perchlorate; maternal T4 is the only source of thyroid hormone for the fetus in the first trimester. 

Blount et al (2007) established that for women with low iodine intake (defined by the World Health 

Organization as urinary iodine < 100 ug/L),[FN51: World Health Organization (WHO). 1994. 

Indicators for assessing iodine deficiency disorders and their control through salt iodization. 

WHO/NUT/94.7. Geneva: WHO/International Council for the Control of Iodine Deficiency 

Disorders.] very low levels of perchlorate exposure were associated with decreased serum T4 and 

increased serum TSH; the CDC estimates that 36% of U.S. women have iodine intakes in this range. 

For iodine-sufficient women (defined as urinary iodine >= 100 ug/L), perchlorate exposure was 

associated with increased TSH. Increased TSH is an indicator that the body is attempting to 

compensate for a decrease in thyroid hormone production, and is clinically considered to be a more 

sensitive marker of subtle thyroid alteration than depressed levels of serum T4. When predicting 

changes in serum TSH with increasing perchlorate exposures, women with low iodine intake and 

TSH levels on the high end of the normal range (> 3.11 IU/L) appeared to be the most sensitive 

group. In this group, any increase in urinary perchlorate predicted an increase in TSH that was 

consistently more than twice the predicted increase in TSH for women with low iodine levels and 
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median TSH levels. For unknown reasons, perchlorate was not associated with T4 or TSH levels in 

men. The observed changes in serum T4 and TSH in women are consistent with our understanding 

of how thyroid hormones are regulated in the body, and with the mechanism of toxicity of 

perchlorate. 

Importantly, the extremely low levels of perchlorate were associated with thyroid hormone 

disruptions - and the magnitude of these disruptions. The CDC researchers found that if a low 

iodine woman started with perchlorate exposure corresponding to 0.19 ppb in urine (the minimum 

level found), and then ingested enough perchlorate through food and/or drinking water to raise her 

urinary perchlorate level to 2.9 ppb (the median level found), her T4 levels would drop by 

13%.[FN52: The drop in T4 predicted to be 1.06 ug/dL; the percentage decrease is calculated as 

compared to the average T4 level found in the CDC study (8.27 ug/dL).] Similarly, if her urinary 

perchlorate level increased to 5.2 ppb (the 75th percentile exposure), her T4 levels would drop by 

16%. The maximum level of perchlorate exposure found was 100 ppb, which translated into a 29% 

decline in T4. 

d. On the merits of the approach EPA used to derive HRLs 

NRDC response: The Greer data no longer represent the best available data. 

Because the dose-response relationship used to determine the RfD is derived exclusively from the 

Greer et al study, the HRL also is dependent on the Greer et al study to determine the maximum 

allowable level of drinking water contamination. 

The Greer et al study [FN53: Greer MA, G Goodman, RC Pleus, and SE Greer. 2002. Health 

effects assessment for environmental perchlorate contamination: the dose- response for inhibition 

of thyroidal radioiodine uptake in humans. Environ Health Perspect 110:927-937.] reported on 

study results from intentional dosing of a small population (N=37) of healthy men and women, for 

only two weeks. That is, the study cannot represent realistic chronic exposure scenarios, and it 

cannot be considered representative of the U.S. population including infants and children. 

Moreover, the study lacked measurements of iodine status that is now known to be a critical 

variable. Other significant weaknesses with the Greer study included the fact that the low dose 

group contained only seven participants including only six women. Use of these limited data to 

calculate a regulatory trigger level has been widely criticized as inadequate by state scientific 

experts[FN54: Ginsberg G and D Rice. The NAS perchlorate review: questions remain about the 

perchlorate RfD. Environ Health Perspect. 2005 Sept; 113(9):1117-9. Erratum in: Environ Health 

Perspect. 2005 Nov; 113(11):A732.] and by EPA's own Children's Health Protection Advisory 

Committee,[FN55: Letter from Melanie Marty to Administrator Johnson regarding Preliminary 

Regulatory Determination on Perchlorate (November 3, 2008, PDF) 

http://yosemite.epa.gov/ochp/ochpweb.nsf/content/perchlorateletter.htm/$file/Per 

chlorateLetter.pdf] and no longer reflects the best available data.[FN56: EN Pearce, AM. Leung, BC 

Blount, HR Bazrafshan, X He, S Pino, L Valentin-Blasini, and LE Braverman, 2007. Breast milk 

iodine and perchlorate concentrations in lactating Boston-area women. J Clin Endocrinol Metab. 

92(5):1673-7.] [FN57: Letter from Melanie Marty to Administrator Johnson regarding Preliminary 

Regulatory Determination on Perchlorate (November 3, 2008, PDF) 

http://yosemite.epa.gov/ochp/ochpweb.nsf/content/perchlorateletter.htm/$file/Per 

chlorateLetter.pdf] Despite these limitations, careful analysis of the Greer data reveal clear evidence 

of perchlorate toxicity in the low-dose group; three subjects showed no perchlorate effect, but four 
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subjects in the low-dose group had a measurable decrease in iodide uptake commensurate with 

perchlorate exposure.[FN58: For a complete analysis of the NAS review of perchlorate, see: 

Ginsberg G and D Rice. The NAS perchlorate review: questions remain about the perchlorate RfD. 

Environ Health Perspect. 2005 Sept; 113(9):1117-9. Erratum in: Environ Health Perspect. 2005 

Nov; 113(11):A732.] Because the study authors relied on averaged data rather than individual data, 

the more sensitive individuals in the study group were obscured 

The short duration of the Greer study, only 14 days, mean that the cumulative effects of longer-term 

exposure are not accounted for. A study in rats found greater perchlorate toxicity to the thyroid 

from 90-day exposure than from 14- day exposure (Springborn Laboratories 1998), suggesting that 

cumulative exposure may cause significant systemic injury that is not detectable in a short-term 

study. Although one sub-chronic (six month) human study with 13 volunteers has been promoted 

by industry as indicating that humans adapt to long-term exposure (Braverman et al. 2006[FN59: 

Braverman LE, EN Pearce, X He, S Pino, M Seeley, B Beck, B Magnani, BC Blount, and A Firek. 

2006. Effects of six months of daily low-dose perchlorate exposure on thyroid function in healthy 

volunteers. J Clin Endocrinol Metab. Jul; 91(7):2721-4. Epub 2006 Apr 24.]) this study was unlikely 

to have adequate statistical power to detect an effect because it failed to consider the widelyrecognized vulnerable populations, including infants, children, and women with low dietary iodide. 

The Blount (2006) study showed that these populations are much more vulnerable to perchlorate 

toxicity than the average population; women are more sensitive than men, iodine-deficient (urinary 

iodide below 100 ug/L) women are more sensitive than iodine-sufficient women, and iodinedeficient women with TSH levels on the high end of the normal range are even more sensitive than 

other iodine-deficient women.[FN60: Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, 

Caldwell KL. Urinary perchlorate and thyroid hormone levels in adolescent and adult men and 

women living in the United States. Environ Health Perspect. 2006 Dec;114(12):1865-71.] Other 

human studies suffer from the same limitations as the Greer study. For example, a study of 

chronically perchlorate-exposed pregnant women in Chile[FN61: Tellez RT, PM ChacÃ3n, CR 

Abarca, BC Blount, CB Van Landingham, KS Crump and JP Gibbs. 2005. Long-term environmental 

exposure to perchlorate through drinking water and thyroid function during pregnancy and the 

neonatal period. Thyroid 15(9):963-975.] that also failed to find an effect of perchlorate exposure 

had only three iodine-deficient female subjects out of 183 in total. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 
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EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28831 

EPA Comment Code: 2500 

Comment: Iodine Deficiency and the IG Report 

In addition to NAS, at least one peer reviewer, several researchers (Amitai et al., 2007, Crump et al. 

2004, Braverman 2007, Tellez et al. 2006) and EPA's IG (December 2008 external review draft 

document, Scientific Analysis of Perchlorate) have suggested that iodine deficiency is the public 

health problem with respect to thyroid malfunction more so than perchlorate. Furthermore, the IG 

report suggests that improving the iodide nutrition level for pregnant and nursing women is the 

most effective way to prevent low maternal total iodide uptake. 

The draft report also states that because perchlorate is only one of many chemicals that affect iodide 

uptake in the thyroid, EPA should have followed a cumulative risk assessment approach in its 

perchlorate risk assessment. EPA's only mention of the IG report in the NODA is to acknowledge 

that the IG Report commented that the agency's risk assessment " account for the activity of other 

compounds with similar actions on the thyroid." The FR then directs the reader to section III.C.2 

for more information, but III C. 2 details issues raised by commenters regarding the occurrence 

analysis and not the risk assessment or the IG report. 

AMWA recommends that the final IG report be released to the public and its recommendations 

considered in EPA's final regulatory determination, particularly with respect to the cumulative risk 

assessment and iodine deficiency. 

The Science of Perchlorate 

Several peer reviewers of EPA's PBPK model as well as the peer reviewers of EPA's 2008 health 

advisory referenced new studies that EPA failed to mention in this NODA. It is important for EPA 

as a scientific agency to objectively and correctly characterize the science of perchlorate in the 

regulatory determination, and consider the body of epidemiological data as well as other health and 

occurrence information, particularly because the topic of possible effects to pregnant women, 

infants and children is such an emotional one. Much has been written in the media about 

perchlorate and its effects and the public and decision makers look to the agency as well as to 

organizations like NAS to help interpret what the science is telling us. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA does not disagree that a total iodine inhibitor load, including naturally-occurring NIS 

inhibitors, should be considered. The Administrator of EPA has suggested a new approach that 

considers cumulative risks of chemical mixtures. At this time we have not given this option full 

consideration. EPA will continue to evaluate the available science related to perchlorate. On August 

19, 2009, EPA published a Federal Register notice requesting supplemental public comments on its 

preliminary determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, 

No. 159, p. 41883). In this August 19, 2009 Federal Register notice, EPA requested comments on 

additional interpretation of data on the level of human health concern, perchlorate frequency of 

occurrence in drinking water, and the opportunity for health risk reduction through a national 

primary drinking water standard, to help determine if it should be regulated. EPA considers both the 

extent of national occurrence and the severity of health effects for a contaminant, as well as other 
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factors (e.g., sources of exposure), when deciding whether regulation presents a meaningful 

opportunity for health risk reduction. Therefore, the Agency considered national occurrence and the 

severity of health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0415 

EPA Comment ID: 28844 

EPA Comment Code: 2500 

Comment: In previous exposure assessments conducted by the EPA, such as arsenic, all available 

epidemiological data was factored into the modeling assumptions, including sensitive 

subpopulations. EPA has clearly omitted significant peer- reviewed studies that provide a significant 

weight of evidence finding that there is no adverse impact from exposure to perchlorate in drinking 

water in the subpopulations that are a focus of this reassessment as summarized in Table 1. This 

omission represents a significant deficiency that countermands the Agency's stated commitment 

[FN3: Memo to Employees from EPA Administrator Lisa Jackson, entitled "Scientific Integrity: Our 

Compass for Environmental Protection". May 9, 2009. 

http://www.epa.gov/Administrator/scientificmemo.html ] and obligation under the SDWA to use 

the "best available peer reviewed science" for supporting sound and technical regulatory 

determinations. 

Table 1. Epidemiological Studies Assessing Effect of Perchlorate Exposure on Children [see PDF 

docket ID EPA-HQ-OW-2009-0297-0415] 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28882 

EPA Comment Code: 2500 

Comment: Dohan et al. (2003) provide perhaps the most comprehensive review of the NIS 

regulation at the time of the NRC report. Dohan et al. reported that "up-regulation of thyroid NIS 
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expression and iodide uptake activity by TSH has been demonstrated not only in rats in vivo but 

also in the rat thyroid-derived FRTL-5 [Fisher rat thyroid cell line] cell line and in human thyroid 

primary cultures. TSH up-regulates iodide uptake activity by an increase in NIS transcription. They 

say: Both NIS mRNA and NIS protein levels decreased significantly after either 1 or 6 days of 

iodide administration. NIS mRNA levels were already significantly reduced at 6 hours following the 

injected single dose of iodide. In contrast, a significant decrease of NIS protein levels was detected 

only at 24 hours. After TSH withdrawal, a reduction of iodide uptake activity is observed in FRTL-5 

cells. This is a reversible process, as iodide uptake activity can be restored by TSH. The NIS half-life 

is approximately 5 days in the presence and approximately 3 days in the absence of TSH (Dohan et 

al., 2003). Other studies support up- regulation of NIS during changing levels of iodine (e.g., Eng et 

al., 1999; Wagner et al., 2002; Merrill et al., 2003; Pedraza et al., 2006; Norden et al., 2007; and 

Bizhanova and Kopp, 2009).] 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28898 

EPA Comment Code: 2500 

Comment: At a recent symposium on perchlorate held in conjunction with the annual Society of 

Toxicology (SOT) meeting in Seattle, Lamm et al. (2008) presented their initial reanalysis of the 

NHANES dataset used by Blount et al. (2006) with an adjustment for urinary creatinine. Lamm et al. 

considered a subset of women from the Blount et al. (2006) study who were of childbearing age (15-

44 years old; the Blount et al. (2006) study group included all women over the age of 12) as well as 

the interaction of thiocyanate and nitrate, both in urine. They found there was no significant 

association between perchlorate and total T4, including women with urinary iodide less than 92 ug/g 

(Figure 3). 

 Figure 3. Urinary reanalysis results of the NHANES data [see PDF docket ID EPA- HQ-OW2009-0297-0662] 

In a peer-reviewed letter to the editor of Thyroid, Gibbs and Van Landingham (2008) reviewed data 

from their previously published study (Tellez et al., 2005), and showed that in a cohort of pregnant 

women in Chile, the data do not support the association between environmental perchlorate 
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exposure and changes in thyroid hormones and are consistent with the recent negative findings by 

both Pearce et al. (2007a) and Lamm et al. (2008), both presented at the Seattle SOT meeting. 

More recently, Mendez et al. (2009) used probabilistic modeling to estimate the total dose of 

perchlorate from food and drinking water using three drinking water scenarios based on UCMR1 

data. The highest estimated dose through water and food was 0.15 ug/kg-d at the 95th percentile, 

well below the RfD of 0.7 ug/kg-d. When compared to the NHANES 2001-2002 estimates based 

on urinary output (used by Blount et al.), they found that intraday variability contributed to the 

overestimation of dose based on the NHANES data. Interestingly, they also found that the urinary 

excretion of perchlorate in NHANES 2003-2004 was significantly lower than in 2001-2002. Two 

data points do not represent a trend, but this lower urinary excretion may represent lower doses 

through food and water in subsequent NHANES studies. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28900 

EPA Comment Code: 2500 

Comment: Steinmaus et al. (2007) 

Steinmaus et al. (2007) used the same dataset as Blount et al. (2006) to assess the correlation 

between smoking, thiocyanate and urinary perchlorate, and thyroid hormone levels. The same 

methodological issues reported for Blount et al. (2006) apply to this study. As in Blount et al. (2006), 

the authors did not find any interaction between perchlorate and smoking and TSH or total T4 in 

women with urinary iodine levels greater than or equal to 100 ug/L or in men. They did conclude 

that in women with urinary iodine less than 100 ug/L, perchlorate increased the risk of lower total 

T4 and higher TSH, just as was reported in the Blount et al. study. This association was stronger 

when the woman was also a smoker or had high urinary thiocyanate levels. 

Amitai et al. (2007) 

This ecological study aimed to "...assess the effect of gestational perchlorate exposure through 

drinking water on neonatal thyroxine (T4)" by comparing T4 levels among newborns whose 
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mothers lived in areas with drinking water perchlorate levels associated with "very high exposure" 

(10 to 100-fold greater compared to levels in the U.S.; >=340 ug/L), "high exposure" (42-94 ug/L), 

or "low exposure" (<3 ug/L). T4 levels were measured within 36 to 48 hours after birth but there 

was no comment on whether the infants were breast fed or formula fed during the postnatal period. 

The authors found that there were no differences between neonatal T4 levels among the groups. 

This study provides evidence that the current RfD and values greater are conservative and health 

protective to the most sensitive individuals in the population. 

Pearce et al. (2007) 

The objective of the Pearce et al. study was "to determine whether breast milk iodine concentrations 

in Boston-area women are adequate for infant nutrition, and whether breast milk iodine 

concentrations may be associated with environmental perchlorate or cigarette smoke exposure." 

Pearce et al. measured breast milk iodine and perchlorate concentrations as well as iodine, 

perchlorate, and cotinine in urine. They then compared the levels found in breast milk to 17 

commercial infant formulae. Neither breast milk nor urinary perchlorate levels were significantly 

correlated with breast milk iodine concentrations. Although perchlorate was detectable in infant 

formulae, the levels were lower than in breast milk. A significant number of women in this study had 

iodine levels that were insufficient to meet the infant's needs, but the authors did not suggest this 

was due to perchlorate exposure or that it represents a chronic iodine deficiency. 

Kirk et al. (2005) 

With the aim to determine what amount of perchlorate children are exposed to, Kirk et al. measured 

perchlorate and iodide levels in cow and human breast milk and compared these values to 

corresponding levels of perchlorate in drinking water in the area. Perchlorate was measurable in 81 

of the 82 samples. The average perchlorate levels in cow milk and human milk were 2 and 10.5 

ug/L, respectively. The maximum levels in cow and human milk were 11 and 92 ug/L, respectively. 

There was no correlation between levels of perchlorate in breast milk and perchlorate in drinking 

water. The authors speculated that there was a correlation between higher levels of perchlorate and 

lower levels of iodine in breast milk; however, they note that this relationship only existed for the 

breast milk samples with the highest perchlorate levels (6 subjects out of 82). The authors recognize 

that this relationship may be coincidental due to the small number of samples with perchlorate levels 

greater than 10 ug/L, stating that "If we take all the available data, there is no meaningful correlation 

between the perchlorate and iodide levels in breast milk." As with previous studies, due to the 

design, this study was not able to evaluate a causal relationship. 

Kirk et al. (2007) 

To determine the variability in the excretion of perchlorate, thiocyanate, and iodide in human milk, 

Kirk et al. had lactating women collect six samples of milk on each of three days or as many samples 

as possible over three days. They found that a significant variation over time for all the anions 

tested. The average iodide, perchlorate and thiocyanate levels were 87.9 ug/L, 5.8 ug/L, and 35.6 

ug/L, respectively. The study was not designed to determine whether perchlorate or thiocyanate 

contributed to IUI in mammary tissue. This study was a biomonitoring study and did not measure 

any adverse effects or exposures. 

Dasgupta et al. (2008) 
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"The objective of this present study was to study the excretion of perchlorate, thiocyanate, and 

iodine in milk and urine and relate the observed pattern within the broad framework of 

parallel/competitive transport by the NIS." Using breast milk and urine samples from 13 lactating 

women and using EPA default values for infant body weights and milk intakes, the authors 

mathematically modeled infant intakes and doses of iodide, perchlorate, and thiocyanate. They 

calculated the fraction of iodide, perchlorate, and thiocyanate in breast milk compared to the total 

that is excreted in both breast milk and urine. They used a ratio of these fractions in milk to 

determine the selectivity of either perchlorate or thiocyanate over iodide. They report "that 12 of 13 

infants did not have an adequate intake of iodine...and 9 out of 13 infants were likely ingesting 

perchlorate at a level exceeding the reference dose..." They also concluded that the selectivity of 

perchlorate over iodide was 3.14+/-1.2. 

There are a number of unresolved issues related to the experimental design of this paper. The 

population is small and there is no information on the selection process of the participants (i.e., they 

are not a random sample). Only three biological variables were measured in the women. The rest of 

the variables, including the variables used to derive the conclusions, are calculated from these three 

or are default values for infant intake and infant weights. The three measurements were the 

concentrations of perchlorate, iodine, and thiocyanate in urine and breast milk. Where other 

research has measured more biologically relevant information, such as serum concentrations of 

analytes that would be most reflective of relative concentrations at the NIS (Tonacchera et al., 2004; 

Pearce et al., 2007), this work is based on very few measured observations. The estimated doses, the 

key variable for understanding possible effects, are based on average body weight and intakes for an 

infant. For such a simple and critical variable and in such a small study population, it is surprising 

that actual body weights were not measured. 

 In addition to study design, the data presented in this paper appear to contradict the interpretation 

by the authors of the paper. Based on estimated weights, the authors say that nine out of 13 infants 

are consuming daily doses in excess of the RfD, yet Table 1 of Dasgupta et al. suggests there are 8 

infants who exceed the RfD of 0.7 ug/kg-d (subjects 1, 2, 8, 11, 13, 15, 16, 20). Furthermore, if one 

reviews these estimates to measured variables, the infants with estimated perchlorate doses greater 

than the RfD are also estimated to have the greatest iodine intake. By plotting the values for total 

iodide excretion (column 4), total perchlorate excretion (column 7), estimated maternal breast milk 

iodide excretion (equivalent to estimated infant iodide intake; column 5), and estimated maternal 

breast milk perchlorate excretion (product of total perchlorate excreted and percent of perchlorate 

in milk; column 7 x column 9) found in Table 1 of the paper, the results demonstrate that 

perchlorate and iodide are positively correlated (See Figure 4). If perchlorate was inhibiting the 

transport of iodide into milk, the association would be negative. 

Figure 4. Plotting of data reported by Dasgupta et al., 2008 to illustrate the association between 

concentrations of iodine and perchlorate in urine and milk in lactating women. [see PDF docket ID 

EPA-HQ-OW-2009-0297-0662] 

In addition to the questions regarding interpretation of the data presented in this paper, there are 

concerns about the interpretation of their previous work (Kirk et al., 2005) and how that study 

impacts this recent study. For example, Dasgupta et al. (2008) remark that "in real mothers 

perchlorate does inhibit the transport of iodine into milk and because of competitive inhibition both 

analytes cannot be high at the same time." This statement, however, is based on a previous study in 
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which the researchers defined their cut off values[FN16: The cut off values from Kirk et al. (2005) 

were defined as follows: High iodide in breast milk was greater than 60 ug/L and high perchlorate in 

breast milk was greater than 20 ug/L.] above which milk iodide or perchlorate was considered 

"high." They report that no milk samples had both high perchlorate and high iodide (Kirk et al., 

2005). In the present study, they report the same trend although they do not define a cut off value. 

Yet if the previous cut off values are applied to the current study, there are many samples that had 

simultaneously high perchlorate and iodide (Figure 4). Based on the previous conclusions about 

competitive inhibition of analytes (Kirk et al., 2005), this study does not demonstrate that 

perchlorate competitively inhibits iodide transport into milk at the concentrations experienced by 

these women. 

Schier et al. (2009) 

The authors measure the concentration of perchlorate in reconstituted powdered infant formula and 

used this information to estimate a mean and upper-bound dose of perchlorate in infants solely fed 

formula. They also estimated the perchlorate concentration in water that would cause an infant in 

the 10th, 50th or 90th percentile of body weight to receive a dose equal to the RfD every day. The 

authors concluded that some infants could be at risk for exceeding the RfD even with minimal 

amounts of perchlorate in water used for reconstitution, but "the clinical relevance of exceeding the 

perchlorate RfD in both an iodide-sufficient and iodide-deficient state are unclear." 

This study provides information to the literature on potential exposures given that all the 

assumptions made about exposure hold true. This study is focused on the exclusively formula fed 

infant. The most sensitive subpopulation for perchlorate health effects and the group that the RfD is 

based, is fetuses of hypothyroid mothers. This paper compares the RfD to estimated doses in a 

population that is not the considered the most sensitive. The RfD is an 

...estimate with uncertainty spanning perhaps an order of magnitude) of a daily oral exposure to the 

human population (including sensitive subgroups) that is likely to be without an appreciable risk of 

deleterious effects during a lifetime. 

This report does not demonstrate that this population is receiving doses of perchlorate at or above 

the RfD. This study suggests that some individuals have the potential to exceed the RfD, if all the 

assumptions implied hold true. Exceeding the RfD is not or meant to be a bright line threshold of 

effects. As noted above, the perchlorate RfD is based on a NOEL in addition to an UF adjustment. 

McLanahan et al. (2009) 

In an attempt to evaluate the mode of action of perchlorate, McLanahan et al. coupled a 

biologically-based dose response model of the hypothalamic-pituitary- thyroid axis with a PBPK 

model for perchlorate. The model was based on rats and evaluated changes in serum thyroid 

hormones with exposure to doses of perchlorate up to 10 mg/kg-d (a DWEL of 350,000 ppb). With 

this high dose, the authors found that the model outputs were inconsistent with observed data from 

experimental studies (Yu et al., 2002). The authors must add a numerical adjustment factor to their 

model so that output from the model agrees with experimental data. They conclude that: 

ClO4- administered in drinking water (or by other routes of administration) interacts with the rat 

thyroid gland itself, potentially altering thyroid hormone synthesis or secretion. This interaction is in 
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addition to blocking thyroidal uptake of iodide. Current presumptions of a single MOA for ClO4- 

on the HPT axis do not appear tenable based on these results. 

Modeling can be very valuable in research. This model, however, is based exclusively on rats. As 

many have noted, rat and human thyroid endocrinology must be evaluated carefully as the 

differences between the two species are important. Rats have smaller stores of thyroid hormones 

and are more sensitive to IUI than humans (NRC, 2005). This model is not able to predict output 

that is consistent with observed experimental data. Thus, without the addition of a numerical 

adjustment factor (called the "proportional inhibition term") this model does not produce 

comparable results to experimental data. The need for this numerical adjustment factor suggests 

unaccounted data needs or terms in the model, a species difference, or the effects of pendrin given 

the higher dose levels. The authors say no more than what is quoted above and provide no 

additional information as an explanation. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Danielle Blacet 

Commenter Organization: Association of California Water Agencies 

EPA Document ID: EPA-HQ-OW-2009-0297-0208 

EPA Comment ID: 28918 

EPA Comment Code: 2500 

Comment: Please accept the attached comments from the Association of California Water Agencies 

on the perchlorate supplemental request for comments. Thank you for your consideration. 

Danielle 

Attachment 

 September 16, 2009 

Water Docket Environmental Protection Agency Mailcode: 2822T 1200 Pennsylvania Ave., NW. 

Washington, DC 20460 

Re: Docket ID No. EPA-HQ-OW-2009-0297, Perchlorate Supplemental Request for Comments 
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To Whom It May Concern: 

The Association of California Water Agencies appreciates the opportunity to comment on the 

United States Environmental Protection Agency’s Supplemental Request for Comments on the 

perchlorate regulatory determination. ACWA represents over 450 public water agencies in California 

that collectively supply over 90% of the water delivered in California for domestic, agricultural and 

industrial uses. ACWA agencies are integrally involved in all aspects of surface water and 

groundwater management statewide to ensure that water supply needs are adequately addressed and 

are committed to ensuring that drinking water is safe for customers throughout California. 

ACWA and its members have a long record of supporting a timely and consistent standard setting 

process, both at the state and federal levels, developed through regulatory channels and governed by 

good science. This support extends to the USEPA regulatory determination for perchlorate. In 

California we have worked diligently with the Office of Environmental Health Hazard Assessment 

(OEHHA) and the Department of Public Health (DPH) on many drinking water regulations, 

including the recent adoption of a maximum contaminant level of 6 parts per billion for perchlorate. 

As the Environmental Protection Agency reviews its initial regulatory determination for perchlorate 

including the potential options for evaluating whether there is a meaningful opportunity for human 

health risk reduction from perchlorate through a national primary drinking water regulation, ACWA 

would like to offer the following comments for consideration in addition to responses for questions 

posed by USEPA: Â Issues for consideration: Â 1) USEPA should carefully consider important 

epidemiological data when reviewing their regulatory determination. 

In four recent rule-making efforts by the USEPA involving arsenic, disinfection byproducts (DBPs), 

radon, and uranium, the risk assessments are based entirely on epidemiological data. In the case of 

arsenic and DBPs, they devote significant time and resources to reviewing numerous 

epidemiological studies with one study selected in each case to actually quantify the risk. 

For example, the Federal Register Notice of the Arsenic Rule had almost three pages of discussion 

of the epidemiological data (7025 - 7027) including reference to epidemiological papers Lewis et al., 

1999, Buchet et al., 1999; Kurttio et al., 1999, Chen et al., 1985; 1988; 1992; Wu et al., 1989, 

Hopenhayn- Rich et al., 1996; 1998, Smith et al., 1998, Morton et al., 1976; Valentine et al., 1992; 

Wong et al., 1992. In spite of several recent and well-designed studies available for review, the 

perchlorate regulatory determination appears to be the only instance where the epidemiological 

literature was not sufficiently considered.[FN1: Crump et.al., 2000, Tellez et.al., 2005, and Amitai 

et.al., 2007] Because USEPA routinely incorporates epidemiological data into these sorts of 

regulatory determinations, they should do so in this case as well. 

Response: EPA acknowledges and thanks you for providing additional information related to 

perchlorate. EPA will continue to evaluate the available science related to perchlorate. On August 

19, 2009, EPA published a Federal Register notice requesting supplemental public comments on its 

preliminary determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, 

No. 159, p. 41883). In this August 19, 2009 Federal Register notice, EPA requested comments on 

additional interpretation of data on the level of human health concern, perchlorate frequency of 

occurrence in drinking water, and the opportunity for health risk reduction through a national 

primary drinking water standard, to help determine if it should be regulated. EPA considers both the 

extent of national occurrence and the severity of health effects for a contaminant, as well as other 
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factors (e.g., sources of exposure), when deciding whether regulation presents a meaningful 

opportunity for health risk reduction. Therefore, the Agency considered national occurrence and the 

severity of health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group (EWG) 

EPA Document ID: EPA-HQ-OW-2009-0297-0499 

EPA Comment ID: 28935 

EPA Comment Code: 2500 

Comment: The most recent studies show widespread exposures: 

The notice in the Federal Register concludes with a section that discusses studies published since 

EPA adopted the NAS RfD for perchlorate. Since EPA adopted the NAS RfD of 0.7 ug/kg/day, 

several comprehensive studies have been published that shed new light on the degree of perchlorate 

contamination in the United States and the possible health implications of this contamination. In a 

fact sheet that accompanied the August 19th notice in the federal register, the agency notes, "The 

key focus of the re-evaluation has been consideration of exposure of infants and young children." 

EWG fully supports this renewed focus on the health threats that perchlorate presents for infants 

and young children. Research from the last few years has established that not only do infants and 

children have higher exposures to perchlorate when compared with adults, they are also more 

vulnerable to its toxic effects. A comprehensive epidemiological study from the CDC also calls into 

question the safety of the current RfD (Blount et al 2006b). Below, we list the evidence from recent 

research that confirms that infants and children are particularly at risk from perchlorate 

contamination of drinking water and why EWG believes that a maximum contaminant level (MCL) 

of no higher than one ppb is a necessary public health measure: 

- A major CDC bio-monitoring study found that children ages six to 11 have higher exposure to 

perchlorate compared with adults (Blount et al 2006a) - An FDA study that found perchlorate 

contamination of 74% of nearly 300 types of commonly consumed foods and beverages also 

confirmed that young children are exposed to more perchlorate, per unit of body weight, from 

contaminated food when compared with adults (Murray et al 2008) - A recent study from CDC 

scientists found that powdered infant formula is widely contaminated with perchlorate (Schier et al 

2009) - Infants and children require more iodine on a body weight basis than adults and could 

therefore be more vulnerable to a thyroid toxin like perchlorate that inhibits iodine uptake by the 

thyroid gland (WHO 1998) - Breast milk testing in the U.S. has revealed wide-spread contamination 

with perchlorate (Kirk et al 2005, Kirk et al 2007, Pearce et al 2007) - Adequate levels of thyroid 

hormones are critical to normal brain development in infants and children and even subtle decreases 

in these hormones during these critical periods can have irreversible effects on cognition (Haddow 

et al 1999, Pop et al 1999) - A major epidemiological study from the CDC finds that perchlorate 

exposures far below the current RfD are associated with significant changes in thyroid hormone 

levels in women (Blount et al 200b) 

Each of these points is further discussed in detail below: 

CDC bio-monitoring study finds that children have higher perchlorate exposure: In 2006, CDC 

scientists published the results of a major bio-monitoring study in which nearly 3,000 Americans 
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ages six and older who are representative of the U.S. population were tested for perchlorate. Every 

single participant was found to have been exposed to perchlorate. Furthermore, children ages six to 

11 had the highest exposure of any group tested, with urinary perchlorate levels that were 1.6 times 

higher on average than in adults (Blount et al 2006a). 

As far as EWG is aware, there has been no testing of urinary levels of perchlorate in children under 

the age of six or infants in the United States. While this is a significant data gap, there is reason to 

believe that infants and young children may be among the most highly exposed groups in this 

country. Infants are at risk for high exposures to perchlorate due to widespread contamination of 

breast milk and infant formula, while young children are especially at risk due to widespread food 

contamination, especially of dairy products such as cow's milk. Widespread contamination of foods 

that infants and young children consume heavily coupled with the fact that children consume more 

food and water per unit of body weight than adults and their relatively small size in comparison with 

adults virtually guarantees that infants and young children have even higher perchlorate exposures 

than children in the six to 11 age group and adults. 

FDA finds widespread perchlorate contamination of commonly consumed foods and beverages: In 

2008, scientists from the FDA published the results of a study in which 285 commonly consumed 

foods and beverages were tested for perchlorate. Their results revealed widespread food 

contamination in the U.S.; perchlorate contaminated 74% of foods and beverages that were tested. 

The FDA scientists went on to estimate daily perchlorate exposures from contaminated foods and 

beverages (excluding tap water) and found that exposures were highest among two year olds. For 

this age group, perchlorate exposures from contaminated food and beverages ranged from 50 and 

56% of the current EPA RfD of 0.7 ug/kg/day (Murray et al 2008). 

The FDA findings are especially concerning because they show that children have high baseline 

exposures to perchlorate from commonly consumed foods and beverages. Overall, the FDA analysis 

found that children ages 10 and under are most highly exposed to perchlorate from contaminated 

foods and beverages. This is because children consume items from food groups that are heavily and 

consistently contaminated with perchlorate, especially dairy foods. In addition, their smaller size in 

comparison with adults means that, pound for pound, they are exposed to higher amounts of 

perchlorate than adults. 

The FDA study, while concerning in itself, has even more profound implications for the children 

who live in any one of the 26 states in which perchlorate has been found in drinking water. EWG 

analysis finds that every proposed or final drinking water standard for perchlorate in the U.S. fails to 

protect two year olds from routine, daily, unsafe exposure when combined food and water 

exposures are considered. A two-year-old of average size could exceed EPA's current RfD by 

drinking water with just four ppb of perchlorate contamination (EWG 2008). A two-year-old of 

smaller size or with above average daily water consumption could easily exceed the RfD at even 

lower drinking water concentrations. The widespread food contamination by perchlorate leading to 

high baseline perchlorate exposures among children underscores the need to set an MCL of <1 ppb 

to minimize combined food and tap water exposure among children. 

CDC scientists find perchlorate in infant formula: Earlier this year, CDC scientists published results 

of a study in which they tested 15 brands of infant formula; they found perchlorate contamination 

of all brands tested. The two most contaminated brands, made from cow's milk, accounted for 87% 

of the U.S. powdered formula market in 2000. The CDC team warned that mixing perchlorate- 
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tainted formula powder with tap water containing "even minimal amounts" of the chemical could 

result in exposures that exceed the current RfD. For example, they note that "reconstitution of PIFs 

(powdered infant formulas) with water containing perchlorate levels of at least 4 ug/l resulted in 

26/48 (54%) dosing scenarios exceeding the RfD". In several other dosing scenarios, the formula 

was so heavily contaminated with perchlorate that formula consumption alone resulted in exposure 

levels above the RfD (Schier et al 2009). This study again underscores how easily vulnerable 

populations such as formula fed infants can exceed EPA's perchlorate RfD when cumulative 

exposures from contaminated food and tap water are considered. 

Increased iodine requirements in infants, children suggest particular vulnerability to perchlorate: The 

World Health Organization (WHO) recommends that the average adult should consume 2 

micrograms of iodine per kilogram of body weight per day to meet daily nutritional requirements. In 

contrast, WHO recommends that young children and infants ingest 3 and 7.5 times more iodine 

respectively per kilogram of body weight per day than non-pregnant adults (WHO 1998). This is 

because thyroid hormone production and turnover are greater in infants and children, compared 

with adults (Ginsberg et al 2007, Meikle 2007). High iodine requirements among infants and 

children may result in particular vulnerability to perchlorate related changes in thyroid hormone 

levels among these populations when compared with adults. This is because perchlorate interferes 

with iodine uptake by the thyroid gland, and since infants and children require more iodine that 

adults, any contaminant that disrupts this process may impact them more severely. This particular 

vulnerability is recognized by the National Academy of Sciences, which noted in a 2005 report that 

in "pregnant women, infants, and children, and people who have low iodide intake or pre-existing 

thyroid dysfunction, the dose [of perchlorate] required to cause a decrease in thyroid hormone 

production may be lower [than for non- pregnant adults]" (NAS 2005). 

Studies reveal widespread perchlorate contamination of breast milk: In three recent studies from 

CDC and academic scientists, samples of human breast milk from different parts of the country 

were tested for perchlorate. Every single sample of breast milk in all three studies was positive for 

perchlorate (Kirk et al 2005, Kirk et al 2007, Pearce et al 2007). In addition, the average levels of 

perchlorate in breast milk in these studies would result in exposure above the agency's RfD for a 

significant numbers of breast-fed infants. 

Further, in all three breast milk studies, a significant number of samples contained insufficient levels 

of iodine to meet the requirement of breast fed infants, meaning that not only would babies drinking 

this breast milk be exposed to hazardous levels of perchlorate by EPA's standards, but they would 

also be deficient in the iodine necessary to counteract the thyroid hormone lowering effects of the 

contaminant, thereby magnifying potential health effects of perchlorate in these infants. 

While there is no question that perchlorate in both food and tap water contributes to breast milk 

contamination, minimizing perchlorate in tap water is an important overall way in which to decrease 

this contamination. There is presumably a relationship between the amount of perchlorate a woman 

consumes and the perchlorate concentration in her breast milk; decreasing her exposure by 

minimizing tap water contamination would most likely result in decreased perchlorate levels in her 

breast milk. In addition, those infants who are fed both breast milk and powdered formula have 

multiple sources of exposure from contaminated breast milk, formula, and tap water used to 

reconstitute the formula. For all of these reasons, setting an MCL for perchlorate of <1 ppb would 

present a meaningful opportunity to reduce breast milk contamination and decrease perchlorate 

exposure among infants. 
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Infants and children particularly vulnerable to toxic effects of perchlorate: Adequate circulating 

levels of thyroid hormones are critical to maintaining normal metabolism in adults, but are especially 

important for infants and children. Infancy and early childhood are times of rapid growth and brain 

development, and any abnormal decreases in thyroid hormone levels during these critical periods 

may lead to inhibition of these processes. Infants and children may suffer from stunted growth and 

delays in intellectual development if they have inadequate levels of thyroid hormones. These impacts 

on growth and brain development can be long-term and irreversible. These concerns recently 

prompted Dr. Melanie Marty, Chair of EPA's Children's Health Protection Advisory Committee 

(CHPAC) to state in a November 3rd, 2008 letter to the agency: 

"The life-long consequences of impaired brain development are sufficient to merit setting a 

protective MCL for perchlorate (CHPAC 2008)." 

Perchlorate exposures below RfD affect thyroid hormone levels: Lastly, EWG would like to address 

the agency's current RfD for perchlorate. On the last page of the notice, the agency states, "EPA 

agrees that additional important data have become available since the RfD was derived in 2005. 

However, EPA has evaluated the new data and has decided to make the regulatory determination 

based on the current RfD." EWG strongly disagrees with this finding and we urge EPA to revise the 

RfD to reflect the most current science. The current RfD was derived from the Greer study, which 

has been critiqued in the peer-reviewed literature and by a state regulatory agency, the Massachusetts 

Department of Environmental Protection. 

A recent large-scale epidemiological study from CDC calls into question the actual safety of the 

agency's RfD (Blount et al 2006b). In September of 2006, CDC scientists published the first major 

epidemiological study using National Health and Nutrition Examination Survey (NHANES) data on 

the potential health impacts of chronic perchlorate exposure. Researchers found a statistically 

significant, dose-dependent association between perchlorate exposure and changes in thyroid 

hormone levels in all of the women in the study. In women with lower iodine levels (one third of 

American women), perchlorate exposure far below the EPA RfD was associated with significant 

changes in thyroid hormone levels. This is the first study to establish iodine insufficiency among 

women as a risk factor for perchlorate induced thyroid toxicity. This new discovery highlights a 

major deficiency in the Greer study; the iodine status of the 37 participants in that study is unknown. 

In the Blount study, women were classified based on urinary iodine levels; those women with 

urinary iodine levels <100 ug/L had significant changes in both TSH and T4 associated with 

perchlorate exposures far below the current RfD. For a subset of women in the study with lower 

iodine levels [those with higher baseline thyroid stimulating hormone (TSH) values], exposure to 

perchlorate as low as five ppb in drinking water was associated with increases in TSH that fall into 

the range of a medical condition called subclinical hypothyroidism. While there is disagreement 

about whether this condition should be treated in non- pregnant women, there is consensus in the 

medical community that pregnant women who develop this condition should be treated with thyroid 

hormone in order to ensure normal brain development of their fetus. 

The results of the Blount study call into question the safety of the RfD and raise the possibility that 

perchlorate exposures in infants and children may be exerting a far more significant clinical effect 

that previously believed. As mentioned above, infants and young children are routinely exposed to 

perchlorate concentrations close to the current RfD from formula, breast milk, and food exposure. 
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Even minimal drinking water contamination can lead to cumulative exposures that exceed the RfD 

among these vulnerable populations. The results from CDC's study, which did not include children 

under the age of 12, suggest that perchlorate exposures far below the current RfD may significantly 

affect thyroid hormone levels in adult women. If the results from the CDC study are extrapolated to 

vulnerable populations, millions of infants and children may be experiencing perchlorate-induced 

disruption in thyroid hormone levels during critical stages of brain development and growth at 

current levels of exposure, far below the current RfD. 

Response: EPA acknowledges and thanks you for providing additional data related to perchlorate. 

EPA will continue to evaluate the available science related to perchlorate. On August 19, 2009, EPA 

published a Federal Register notice requesting supplemental public comments on its preliminary 

determination not to regulate perchlorate in drinking water (Federal Register Vol. 74, No. 159, p. 

41883). In this August 19, 2009 Federal Register notice, EPA requested comments on additional 

interpretation of data on the level of human health concern, perchlorate frequency of occurrence in 

drinking water, and the opportunity for health risk reduction through a national primary drinking 

water standard, to help determine if it should be regulated. EPA considers both the extent of 

national occurrence and the severity of health effects for a contaminant, as well as other factors (e.g., 

sources of exposure), when deciding whether regulation presents a meaningful opportunity for 

health risk reduction. Therefore, the Agency considered national occurrence and the severity of 

health effects from perchlorate and concluded that regulation was warranted, so EPA has 

determined that perchlorate will be regulated. 
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EPA Comment Code: 2600 Comments on expanding scope of risk assessment 

to include other goitrogens and/or dietary iodide deficiency 

Individual Comments 

Commenter Name: Jonathan Borak 

Commenter Organization: Yale School of Medicine 

EPA Document ID: EPA-HQ-OW-2009-0297-0209 

EPA Comment ID: 28508 

EPA Comment Code: 2600 

Comment: 3). OIG presented a compelling argument that perchlorate regulation should not be 

based on risk assessment of perchlorate alone, but on an assessment of the complex mixture of 

naturally-occurring NIS stressors that includes perchlorate. Moreover, "lack of iodine in the diet 

(a.k.a. iodide deficiency)" is the most important of those NIS stressors (13). 

Response: See response to comment ID 28529 under comment code 2500. 

Commenter Name: Andria Ventura 

Commenter Organization: Clean Water Action et al. 

EPA Document ID: EPA-HQ-OW-2009-0297-0528 

EPA Comment ID: 28514 

EPA Comment Code: 2600 

Comment: EPA must also consider other exposure pathways and additional contaminants in the 

environment that impact thyroid function when establishing the MCL. Studies of perchlorate levels 

in food, including breast milk, show that the population is exposed through multiple pathways in 

addition to contaminated drinking water. EPA should determine potential aggregate exposures 

based on a broad range of contamination levels, and not just the mean, which was the basis for 

current estimates. 

While data have also demonstrated a particular threat to the significant number of individuals, 

especially women of child-bearing age who are iodide deficient, the current modeling does not 

include this threat. Given this widespread problem (CDC estimates up to 30% of women do not get 

sufficient dietary iodide), it is critical to take into consideration the potential for exposure to other 

thyroid- active agents. Consequently, EPA must consider the cumulative impact of perchlorate, 

other substances in the environment that inhibit the uptake of iodide by the thyroid, and inadequate 

supplies of iodide in American diets, all of which makes a stringent drinking water standard 

necessary to be truly health protective. 

Response: See response to comment ID 28529 under comment code 2500. 

Commenter Name: Shannon Cunniff 

Commenter Organization: Department of Defense (DOD) 

EPA Document ID: EPA-HQ-OW-2009-0297-0411 

EPA Comment ID: 28522 

EPA Comment Code: 2600 
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Comment: Comment No. 10 

Section III.A. 4. Request for Comment on Alternative Approaches. 

Page & Paragraph Page 41886 

Comment We believe that at this time, PBPK modeling is necessary to be able to more fully 

consider sensitive subpopulations' exposure to chemicals that bind to the NIS receptor such as 

perchlorate, thiocyanate, and nitrate from dietary sources and the significance of low levels of 

perchlorate in drinking water. EPA should consider whether thiocyanate and nitrate may have a 

much greater impact than perchlorate for the most sensitive subpopulations with insufficient iodide 

and how best this can be resolved. 

Consideration should also be given to the differences in the rate of excretion of thiocyanate and 

nitrate in human urine compared to perchlorate and the half- life of each (relative amount of time in 

the body from ingestion prior to excretion and the differences in the strength of iodide uptake 

inhibition). 

Suggested Action, Revision and References (if necessary) We also recommend validation and/or 

comparison of the results of the current EPA revised PBPK model (2009) with biological fluid data 

derived that are available from perchlorate exposure studies. Studies include those recently published 

by the CDC and NIEHS (Blount et al., 2009) and the longitudinal epidemiologic study of pregnant 

women in Northern Chile (references provided below) as well as other scientifically sound human 

data. The CDC and NIEHS study reported not only new sensitive subpopulation-related perchlorate 

and iodide biological fluid data but they also compared thiocyanate and nitrate found in maternal 

and fetal compartments to levels found in other published studies. We believe that consideration of 

such data is consistent with EPA's statement made in the FR announcement that they will 

"...continue to evaluate any new perchlorate data to determine its relevance to the regulatory 

determination in accordance with the SDWA." 

References: Blount et al. 2009, "Perinatal Exposure to Perchlorate, Thiocyanate, and Nitrate in New 

Jersey Mothers and Newborns." Environ. Sci. Technol. 

http://pubs.acs.org/doi/pdfplus/10.1021/es9008486 

Tellez et al. "Long-term environmental exposure to perchlorate through drinking water and thyroid 

function during pregnancy and the neonatal period." Thyroid 2005, 15, 963-975. 

Category* S. M. 

Response: See response to comment ID 28529 under comment code 2500. EPA concluded that 

the PBPK modeling analysis, in the context of the perchlorate regulatory determination, is useful in 

examining which life stages are most susceptible to the effects of perchlorate. For example, the 

model indicates that a fetus may be seven times more sensitive to the effects of perchlorate than a 

pregnant woman. The model also allows for the estimation of the concentration of perchlorate in 

breast milk (thus breast-fed infant exposure) at various maternal perchlorate exposure levels. 

However, because of the stated limitations, EPA has decided the model does not directly bear on 

the current decision regarding the need for a NPDWR for perchlorate. 
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Commenter Name: John P Gibbs 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0636 

EPA Comment ID: 28552 

EPA Comment Code: 2600 

Comment: 3) OTHER NIS INHIBITORS 

Although the NAS committee members were aware of the significance of other NIS inhibitors and 

had access to the Tonaccera et al 2004 study, they were restricted by their charge to considering only 

perchlorate. All NIS inhibitors share the same mechanism of toxicity as perchlorate by blocking the 

uptake of iodide by the thyroid. The risk to public health is from the combined amount of NIS 

inhibition acting on the body from all three NIS inhibitors (thiocyanate, nitrate, and perchlorate). 

The combined total NIS inhibition load acting on the thyroid (not just perchlorate exposure) 

determines the total iodine uptake level and the subsequent potential for an adverse outcome. 

Adverse thyroidal effects of high concentrations of thiocyanate have been reported in numerous 

studies (Gibbs, 2006) 

As noted in the OIG draft report, perchlorate, thiocyanate, nitrate and low iodine intake fit the 

criteria of a cumulative risk assessment. OIG reports that thiocyanate, nitrate, and iodine are found 

naturally in food and water sources, assuming that people are not exposed to any one of these 

chemicals alone, but in combination. Thus, the focus on one chemical does not in fact provide a 

scientifically accurate assessment of possible human health risk. The cumulative risk assessment 

approach provides the best opportunity to impact public health. 

Response: See response to comment ID 28529 under comment code 2500. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0653 

EPA Comment ID: 28560 

EPA Comment Code: 2600 

Comment: The 15 ppb drinking water level proposed under the October 2008 preliminary guidance 

is sufficiently protective as few drinking water systems were shown to exceed this level in the 2000-

2001 sampling of water systems. Fewer systems are likely to even reach this level as states such as 

California and Massachusetts have since set more stringent drinking water levels of 6 ppb or below, 

and sources of potential contamination are being remediated. For these reasons, EPA has difficulty 

justifying that meaningful public health protection will result from regulation as the percentage of 

the public residing outside of states where regulations are already in place, and where perchlorate 

occurrence in drinking water supplies is at a meaningful level, is remarkably small. It appears that 

EPA has attempted to push the limit lower in an attempt to justify larger numbers of population 

affected in order to meet the SDWA criteria concerning exposure/occurrence. The Agency has not 

addressed in its analysis that the population of an area that may be impacted fails to differentiate that 

most adults and older children are not as sensitive to the effects of perchlorate as the fetus of a 

pregnant woman, the subpopulation identified by the NRC as being the most sensitive. Instead, 
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EPA has attempted to use the total number of population exposed by a water provider with 

perchlorate occurring in drinking water as being equally exposed and equally at risk. This assessment 

ignores that more targeted means of addressing potential sensitivities, or personal concerns, may be 

effected through the consumption of bottled water (a common practice that is not factored into 

EPA's analysis), or the provision of a diet with sufficient iodine to make a drinking water consumer 

less likely to be iodine deficient. Even with regulation, EPA's efforts do nothing to focus public 

health efforts on attaining iodine sufficiency and, therefore, miss the real public health threat. 

Response: EPA disagrees. EPA is using a data driven approach considering the totality of the best 

available, peer reviewed data to develop an NPDWR that is protective of human health. EPA will 

consider the economic impacts of the proposed MCL in developing theNPDWR. 

Commenter Name: Richard M. Peekema 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0419 

EPA Comment ID: 28687 

EPA Comment Code: 2600 

Comment: I believe the percentage of iodide deficient women several decades ago was possibly half 

what it is at the present. It seems likely that the media coverage of excess salt intake has caused 

many individuals to self medicate, avoid salt, and indirectly limit their iodide intake. This changes the 

size of the population at risk. Similar changes are possible in the amounts of thiocyanate and nitrate 

which people ingest. The EPA provides the following info on p.41892 in its FR solicitation for 

comments: 

An additional key scientific issue was raised by EPA's OIG in the report released for public 

comment "OIG Scientific Analysis of Perchlorate (External Review Draft)" (EPA, 2008g). The 

report states, 

The OIG [Office of Inspector General] Analysis concludes that a single chemical risk assessment of 

perchlorate is not sufficient to assess and characterize the combined human health risk from all four 

NIS stressors, (i.e., thiocyanate, nitrate, perchlorate and lack of iodide) and that * * * Only a 

cumulative risk assessment can fully characterize the nature and sources of risk affecting this public 

health issue. Furthermore, a cumulative risk assessment allows an informed environmental decision 

to be made on how to mitigate the risk effectively. 

The report goes on to say, Potentially lowering the perchlorate drinking water limit from 24.5 ppb to 

6 ppb does not provide a meaningful opportunity to lower the public's risk. By contrast, addressing 

moderate and mild iodide deficiency occurring in about 29% of the U.S. pregnant and nursing 

population appears to be the most effective approach of increasing TIU [total iodide uptake] to 

healthy levels during pregnancy and nursing, thereby reducing the frequency and severity of 

permanent mental deficits in children. 

I concur completely, and endorse this position. Additionally, the fact that iodide deficiency, 

thiocyanate, and nitrate content in the population at risk are all changing quantities over time make it 

inappropriate to set a hard and fast MCL that is scientifically sound. There is nothing wrong with 

changing an MCL when new information comes to light regarding the action of that contaminant on 
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the population at risk. It is another matter, however, when the population at risk changes over time 

and should in prudence be mitigating that risk by other health means. 

Response: EPA has determined that a NPDWR for perchlorate is warranted. See response to 

comment ID 28529 under comment code 2500 

Commenter Name: Kay Brothers 

Commenter Organization: Southern Nevada Water Authority 

EPA Document ID: EPA-HQ-OW-2009-0297-0667 

EPA Comment ID: 28696 

EPA Comment Code: 2600 

Comment: The Safe Drinking Water Act (SDWA) specifically mandates that the EPA use the "best 

available peer reviewed science" for supporting sound and technical regulatory determinations. 

However, to date the EPA seemingly has not considered the valuable epidemiological data available 

in peer-reviewed literature. The epidemiological studies and other human studies, most notably 

Greer 2002 (Greer, Goodman et al. 2002), take into account the relative source contribution (RSC). 

By utilizing the wealth of data provided in these studies, the EPA would no longer need to consider 

Relative Source Contribution (RSC) when health effects, or no observed adverse effects levels 

(NOAELs), are calculated using these and other human-exposure studies. While a potential criticism 

lies in the theoretical absence of specific subjects with iodine deficiencies, we agree with the EPA's 

Inspector General in stating that regulatory action under the SDWA is not the appropriate or 

effective way to address the overarching public health issue - iodide deficiency. For these reasons 

alone, we believe that epidemiological data available for exposure to perchlorate through drinking 

water should be evaluated before turning to the more nebulous PBPK modeling. 

Response: See response to comment ID 28718 under comment code 2600 

EPA concluded that the PBPK modeling analysis, in the context of the perchlorate regulatory 

determination, is useful in examining which life stages are most susceptible to the effects of 

perchlorate. For example, the model indicates that a fetus may be seven times more sensitive to the 

effects of perchlorate than a pregnant woman. The model also allows for the estimation of the 

concentration of perchlorate in breast milk (thus breast-fed infant exposure) at various maternal 

perchlorate exposure levels. However, because of the stated limitations, EPA has decided the model 

does not directly bear on the current decision regarding the need for a NPDWR for perchlorate 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0647 

EPA Comment ID: 28715 

EPA Comment Code: 2600 

Comment: Water Docket ID No, EPA - HQ - OW - 2009 - 0297 

Supplemental comments regarding the fundamentally different outcomes between Greer, et al, 2002 

and the Blount, et al, 2006 studies on low dose effects of perchlorate 

By: Herwig Opdebeeck, SM, Opdebeeck Consulting[FN1: Mr. Opdebeeck can be reached at +41 79 

658 7979, or h.opdebeeck@opdebeeck.ch.], October 8th, 2009 
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Executive summary 

In the Blount study, an association between perchlorate levels and TSH was found at levels four 

orders of magnitude lower than has been found in previous studies. However, this result does not 

appear to represent a causal relationship between perchlorate and TSH, due to the inconsistent 

results exhibited by perchlorate and the other goitrogens, thiocyanate and nitrate, within the same 

study. To our knowledge, no in depth study has been published which explains these inconsistencies 

exhibited by the Blount study in a manner that would continue to support its conclusions and allow 

the study to be used as the basis for regulation of perchlorate. Instead, our analysis of the other 

substances not controlled for in this cross sectional study supports the conclusion that the 

inconsistent and unexpected results of the Blount study are the result of causal associations between 

these other substances and thyroid hormone levels. 

Even though only a few of the many substances with the capability of affecting thyroid function 

were surveyed in the same NHANES database on which the Blount study was based, we found 

several that showed the same association with TSH. Added to the fact that the association of those 

substances with thyroid hormone was at levels that are known to cause those effects and not at 

levels four orders of magnitude lower as was the case for the perchlorate association, it is apparent 

that the association with thyroid hormone found in the Blount study is not due to perchlorate but 

due to a pool of goitrogenic substances of which the perchlorate background is only a marker. 

In conclusion, not only didn't the Blount study show an upstream iodine inhibition (i.e., it didn't 

show a relationship between iodine and THs), but additionally perchlorate, which only represents 

1% of the NIS goitrogen load, and all three NIS goitrogens seem to have been fully compensated by 

iodine - explaining the non-relationship of iodine with TH. For the NIS goitrogen perchlorate, it 

should also be noted that at background levels, it is a strong predictor of environmental iodine 

background levels. Additionally, goitrogenic compounds shown to have a direct effect on TH levels 

and at levels know to cause such effects, were found to be associated with TSH as well, without 

exhibiting the inconsistencies found in the Blount study. Finally, a plausible link can be found 

between those compounds and perchlorate, a marker for the goitrogenic pool through the chlorine 

link. 

Acronyms BW: Body weight of an adult (70Kg) DW: Drinking water DWL: Daily drinking water 

consumption in litres (2 L) DBP: Disinfection by-products EGP: Environmental goitrogenic pool 

(see GC) MCL: Maximum contaminant level NAS: National Academy of Sciences =NRC NIS: 

Sodium iodine symporter NOEL: Non observed effect level NRC=National Research Council = 

NAS DWS: Drinking water standard GC: goitrogenic contaminants (substances that inhibit iodine 

uptake and therefore could affect TH levels or substances such as PCBs that directly affect TH 

levels) OIG: EPA's Office of Inspection General PHG: Public health goal RfD: Reference dose 

sum23PCB= the sum of the concentrations of 23 PCBs in the NHANES 2001-2002 dataset. TGL: 

Total (NIS) goitrogen load TH: thyroid hormone UF: Uncertainty factor UPEC (or UTGL): Urinary 

perchlorate equivalent concentration expressed in PEC: [Perchlorate] + [nitrate/150] + 

[thiocyanate/8.8] with concentrations in weight. 

Response: EPA will consider the totality of the best available, peer reviewed science in developing 

the NPDWR for perchlorate. Data will be evaluated using a weight of evidence approach, 

considering each study in the context of the entire database. 
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Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0647 

EPA Comment ID: 28718 

EPA Comment Code: 2600 

Comment: Summary 

Preliminary note: When expressing a relationship between variables in a cross- sectional study we 

sometimes use the term "predictor of "(term used in Blount et al. study) which has the same 

meaning as "associated with" or "related with". 

We statistically analyzed some of the other substances contained in the same NHANES 2001-2002 

data on which the Blount et al. study was based, and found similar statistically significant 

associations between some of those substances and TSH. We did not look for associations with T4 

since, after adjusting for creatinine, the association between perchlorate and T4 disappeared for the 

pertinent subpopulation, women of childbearing age with insufficient levels of iodine[FN4: Lamm 

SH, Hollowell JG, Engel A, Chen R (2007). Perchlorate, thyroxine, and low urine iodine association 

not seen with low creatinine- adjusted urine iodine among women of childbearing age. Thyroid 17 

(s1):S-51]. 

Indeed there exist many other goitrogenic substances that have a different mode of action not 

related to iodine uptake inhibition. The Blount study is about possible effects on THs of substances 

present in the population sample. Therefore, all known substances that affect TH levels, all 

goitrogenic contaminants (GC), should have been statistically tested and controlled for as well and 

not only those that act through the same mechanism as perchlorate. Since iodine levels are probably 

not relevant to explain the Blount TH level changes as they are not associated with TH levels in the 

same population sample, we should, in order to find a cause, not look with priority for goitrogens 

that affect NIS function (i.e. uptake of iodine) but GCs that directly affect TH levels. 

EPA's current RfD for perchlorate is based on perchlorate's ability to competitively inhibit the 

thyroid gland's uptake of iodide. It is, therefore, surprising that EPA does not raise this issue when 

commenting on the Blount study, but instead limits itself to discussing nitrate and thiocyanate. If the 

Blount et al. study was focused on the iodine uptake inhibition effect, then this would have been 

justified. But it was not. Instead, it was about the downstream effect, the effect on TH. There are 

indeed hundreds of environmental contaminants, natural and synthetic, that directly affect thyroid 

hormone levels and which we can call the environmental goitrogenic pool (EGP). Many have not 

been studied and none were tested and controlled for in the Blount study, even though the levels of 

some were available in the NHANES 2001-2002 database of the same population for which the 

perchlorate - TH relationship was found. We found that the relationship between some of those 

substances i.e., (certain organo- halogens) with TH was similar with the one of perchlorate. 

We found that the sum of the concentrations of 23 PCBs from the NHANES 2001-2002 database 

was a predictor of TSH for the same Blount total population (p= 0.0037). For women, we found 

that sum23PCB was a significant predictor of TSH (p=0.0027) and that there was no iodine 

interaction, or in other words the relationship of sum23PCB was the same for all levels of iodine, or 
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the PCB-TSH relationship was not influenced by the iodine level. For men sum23PCB was not a 

significant predictor of TSH. 

For the total population sample, we also found that pp-DDE was a significant predictor of TSH 

(p=0.0185). For women, but not for men, pp-DDE was a significant predictor of TSH (p=0.0040) 

and again without iodine interaction which is coherent. 

We suggest that the main link between perchlorate and those goitrogenic contaminants that directly 

affect TH levels is the element chlorine via chlorophenols, some of which originate in disinfection 

by-products (DBP) and many other processes where chlorine derivates are involved. The threshold 

effect level on THs of organohalogens such as PCBs and other dioxin- like mostly chlorine based 

organic substances has been found to be in the range of 0.1 to 10 ug /l serum depending on the 

substance. The levels of those substances found in NHANES 2001-2002 is in this range and, as 

mentioned, a relationship between some of these substances and THs was found as well. This is in 

stark contrast with the four orders of magnitude difference between the effect level of perchlorate 

on THs known from the body of the literature and the perchlorate levels that were related with THs 

found in the Blount study. 

Opting for the broad picture and looking for the most likely cause of these effects produced leads 

which, when compared to the data, points toward a vast pool of goitrogenic compounds, natural and 

synthetic as the source of impacts to TH. Of these, the low level perchlorate background is only a 

marker, most probably through the chlorine link, rather than the cause. 

In order to answer the question presented in the heading, we propose the following steps: 

2.1. Opting for the broad picture 

We hear a lot about the value of holistic approaches and cumulative risk assessment in documents 

such as: US Environmental Protection Agency (US EPA), Framework for Cumulative Risk 

Assessment, EPA/630/P-02/001F, National Center for Environmental Assessment, Office of 

Research and Development, Washington, DC, 2003a, available at 

http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=54944. 

This is an excellent opportunity to put it in practice. EPA's OIG in its December, 2008 study on 

perchlorate[FN5: Office of Inspector General Scientific Analysis of Perchlorate ,Assignment No. 

2008-0010, December 30, 2008.] certainly took an important step in that direction, and we agree that 

a cumulative approach is critical to the accurate evaluation of perchlorate’s risks, and should be the 

underpinning for any regulatory decision making regarding perchlorate. 

2.2. Looking for the "culprit(s)" where they are most likely to be 

There exist many other goitrogenic substances which lead to TH level change, that have a different 

mode of action (not related to iodine uptake inhibition) than the traditional NIS affecting 

goitrogens. The Blount study is about possible effects on THs of background contaminants. 

Therefore, all known contaminants that affect TH levels should have been statistically tested and 

controlled for as well and not only those that act through the same mechanism as perchlorate. Since 

background iodine levels are probably not relevant to explain the Blount TH level changes, as they 

are not related to TH levels in the same population sample[FN6: 1. Charnley G, Perchlorate: 
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Overview of Risks and Regulation. Food and Chemical Toxicology, 2008. 2. Soldin OP, Tractenberg 

RE, Pezzullo JC. Do thyroxine and thyroid-stimulating hormone levels reflect urinary iodine 

concentrations? Therapeutic Drug Monitoring. 2005, 27: 178-185.], we should not look primarily at 

goitrogens that affect the uptake of iodine (and therefore have only a potentially indirect effect on 

TH levels) but goitrogenic contaminants (GCs) that directly affect TH levels. 

EPA's current RfD for perchlorate is based on perchlorate's ability to competitively inhibit the 

thyroid gland's uptake of iodide. Therefore, it is surprising that EPA does not raise this issue when 

commenting on the Blount study, but limits itself to mentioning nitrate and thiocyanate. If the 

Blount study had been about iodine uptake inhibition effect then this would have been justified. But 

it was not. Instead, it was about the downstream effect - i.e., the effect on TH levels. However, in 

the Blount study it was assumed that iodine uptake inhibition was the upstream effect, so much so 

that the study population had been split into 2 groups -- iodine deficient and iodine sufficient. This 

only created additional inconsistencies, as it exposed additional "unexpected" relationships which 

should have been seen as a warning that something was amiss. 

Limiting the whole issue to iodine uptake inhibitors, of course, made the study much simpler to 

manage, but was not the right way to draw plausible conclusions about cause. 

2.3. Looking for a lead 

We quote from the January 2008 Thyroid journal: 

"Toxicological models and limited epidemiological studies have indicated that many organohalogen 

aromatic compounds, including dioxins, polychlorinated biphenyls (PCBs), and polybrominated 

diphenyl ethers (PBDEs), may be classified as "endocrine disruptors, as they have the potential to 

alter normal thyroid function." 

"Because environmental exposures rarely occur singly, it is often difficult to disentangle a single 

exposure from other co-occurring environmental exposures and conditions that may confer risks 

upon children. Therefore, there is often the potential for confounding, in which both the exposure 

and the outcome under investigation are related to a third factor that may distort the observed 

exposure-disease relationship." 

"In epidemiologic studies, it is critically important to identify, measure, and control for such 

confounders." 

Therefore, other substances could have caused the TH changes. 

While NHANES 2001-2002 TH levels, as mentioned before, do not reflect urinary iodine 

concentrations, serum PCBs, p,p'-DDE and HCB background levels predict TH levels[FN7: John 

D. Meeker, Larisa Altshul, Russ Hauser. Serum PCBs, p,p'-DDE and HCB predict Thyroid 

Hormone Levels in Men. Environ Res. 2007 June; 104(2): 296-304.] and some do so in NHANES 

1999-2002 survey population as well[FN8: Mary E. Turyk, Henry A. Anderson, Victoria W. Persky. 

Relationships of Thyroid Hormones with Polychlorinated Biphenyls, Dioxins, Furans, and DDE in 

Adults. Environmental Health Perspectives. August 2007,Volume 115, Number 8.]. However the 

background levels of only few such substances have been measured and tested against TH levels. 
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Yet in the NHANES 2001-2002 survey, a few of those substances have indeed been measured and 

therefore can be tested for associations with other contaminants in the same survey. 

2.4. Focusing initially on those type of substances that are already in the NHANES 2001-2002 

survey of the same population surveyed by Blount 

Since organochlorides such as PCBs, DDE and other organochlorides that have been shown to 

directly affect TH levels are included in that survey, it should have been obvious that those 

substances should have been considered in the Blount study in the first place -- or at least controlled 

for before any other relationship was suggested. 

2.5. Comparing the data on the different "suspects" comprised in the NHANES dataset 

Preliminary note: We did not look for associations with T4 since, after adjusting for creatinine, the 

association between perchlorate and T4 disappeared for the pertinent subpopulation, iodineinsufficient (UI<100 ug/L) women of childbearing age (see ref. 4). 

(a) Perchlorate versus TSH for the total (male plus female) population 

The Blount study did not show that perchlorate was a significant predictor[FN9: In this paper we 

use the same term "predictor of" as used by Blount et al. which means the same as "associated with" 

and "related with", terms we also use in this paper.] of serum TSH. (p>0.05) for the total 

population. 

(b) Sum of some PCBs versus TSH PCBs are one group out of a multitude of other substances that 

act on thyroid function (see details in Appendix 2). 

We found that the sum of the concentrations of 23 PCBs from the NHANES 2001-2002 database 

was a predictor of TSH for the same total population (p= 0.0037) 

(c) Perchlorate and PCBs versus TSH controlled for gender 

For women (all), Blount's data indicates that perchlorate was a significant predictor of TSH (note 

that Blount did not publish a p value, but we found p= 0.0153 and R2=0.006) and no iodine 

interaction which is consistent if the predictor is not the cause. 

For women < 100 ug/l UI, perchlorate was a significant predictor of TSH (p= 0.001). 

For women > 100 ug/l UI, perchlorate was a significant predictor of TSH (p= 0.0249) which is 

inconsistent if the predictor (perchlorate) is the cause and consistent if the predictor is not the cause. 

For men, Blount found that perchlorate was not a significant predictor of TSH. Further, as 

mentioned in our previous comment (EPA-HQ-OW-2009-0297-0227), we found that in the Blount 

study there was a strong relationship between iodine and perchlorate (p<0.0001 and R2= 0.36). This 

is an additional indication that perchlorate could not have affected TSH, in addition to the other 

main arguments: i) an upstream iodine inhibition was not shown; ii) there was no relationship 

between iodine and THs; iii) perchlorate only represents 1% of total NIS related goitrogen load and; 

iv) perchlorate levels seem to have been compensated by iodine. In fact, iodine levels not only seem 
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to fully compensate for perchlorate levels but also for the levels of the other two NIS goitrogens, 

nitrate and thiocyanate or conversely, low levels of iodine were compensated for by low levels of 

goitrogen load (see Appendix 3). 

For women, we found that sum23PCB was a significant predictor of TSH (p=0.0027) and that there 

was no iodine interaction, or in other words the relationship of sum23PCB was the same for all 

levels of iodine or the PCB-TSH relationship was not influenced by the iodine level. For men 

sum23PCB was not a significant predictor of TSH. 

(d) pp- DDE (dichlorodiphenyldichloroethylene) as a predictor for TSH In Appendix 2, we 

demonstrate in detail the relationship between pp-DDE, another dioxin-like organochlorinated 

compound found in the NHANES 2001-2002 dataset, and TSH. The associations compared with 

those of perchlorate are summarized as follows: 

* For the total population sample, our study found that pp-DDE was a significant predictor of TSH 

(p=0.0185) * For women, but not for men, pp- DDE was a significant predictor of TSH (p= 

0.0040). * Further we did some additional analyses and found the following additional relationships 

or outcomes when investigating the association between pp-DDE and TSH: 1. There was no 

interaction between pp-DDE and iodine and gender, which is consistent (as it is expected in the case 

of a non-NIS goitrogen) 2. There was no interaction between gender and iodine. 3. There was no 

interaction between iodine and pp-DDE, which is consistent (as it is expected in the case of a nonNIS goitrogen) 4. There was no effect of iodine on TSH (see ref. 6), which is consistent (expected : 

see ref. 6) 5. After correcting for pp-DDE, an increase of perchlorate was associated with an 

increase of TSH, only for females (p=0.0003). 6. After correcting for perchlorate, an increase of ppDDE was associated with an increase of TSH, only for women (p=0.004). 

Conclusion: Only one single goitrogenic organochlorinated substance directly affecting the level of 

THs is already associated with TSH at environmental background concentrations, and all other 

outcomes are consistent with expected results. 

2.6. Looking for links between perchlorate and the members of the goitrogenous pool 

To further support the absence of a causal relationship between perchlorate with TH, ideally a 

second relationship -- a relationship between perchlorate and those organo- halogens that directly 

affect TH levels -- should be found. Although it is difficult to statistically demonstrate this 

relationship, due to the presence of other confounding environmental GCs, the most obvious and 

most widely spread common link is chlorine via chlorophenols. For additional explanation, see 

Appendix 1. 

Following a summary of Appendix 1: -DBP road 1: From bleach/Cl2/Cl-/chloramine->-> ClO3 -> 

ClO4- -DBP road 2 (in presence of organic (C) material): From bleach/ Cl2/Cl-/ chloramine->-> 

phenols ->-> organochlorides / dioxins with DBP= Disinfection by- products 

Since organo-chlorinated compounds are ubiquitous, and since we find at least 1/3 of the total 

dietary perchlorate where we find organo-chlorinated compounds (see Appendix 1), and since many 

of those have been shown to affect TH levels, it is to be expected that low levels of perchlorate are 

associated with TH levels as found in the Blount study. This association, however, does not 

demonstrate causation, as Blount suggests. Given the complicated and overlapping effect of many 
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substances on TH levels, assigning cause to this association between perchlorate and TH levels 

defies logic and does not explain the inconsistencies revealed within the study itself. 

Instead, perchlorate appears to be a marker, a "witness" of the presence of ubiquitous goitrogenic 

contamination caused by the net effect of hundreds of substances (See also section 2.8). Instead of 

representing the cause of the impact, perchlorate is correlated to the presence of other ubiquitous 

goitrogenic substances which contribute to the overall impact on TH. This alternative explanation 

makes logical sense, and explains the contradictions and inconsistencies regarding the other NIS 

goitrogens found in the Blount study. 

2.7. Finally, the "alibi": background levels found compared with known effect levels 

The known threshold effect level on THs of organohalogens such as PCBs and other dioxin-like 

substances has been found to be in the range of 0.1 to 10 ug /l serum depending on the 

substance[FN10: Lesa L. Aylward, Julie E. Goodman, Gail Charnley, Lorenz R. Rhomberg. A 

Margin-of-Exposure Approach to Assessment of Noncancer Risks of Dioxins Based on Human 

Exposure and Response Data. Environmental Health Perspectives. October 2008. Volume 116, 

Number 10.][FN11: Lawrence M. Schell, Mia V. Gallo, Melinda Denham, Julia Ravenscroft, 

Anthony P. DeCaprio, David O. Carpenter. Relationship of Thyroid Hormone Levels to Levels of 

Polychlorinated Biphenyls, Lead, p,p'- DDE, and Other Toxicants in Akwesasne Mohawk Youth. 

Environmental Health Perspectives. June 2008, Volume 116, Number 6.] [FN12: Johan Maervoet, 

Griet Vermeir, Adrian Covaci, Nicolas Van Larebeke, Gudrun Koppen, Greet Schoeters, Vera 

Nelen, Willy Baeyens, Paul Schepens, Maria K. Viaene. Association of Thyroid Hormone 

Concentrations with Levels of Organochlorine Compounds in Cord Blood of Neonates. 

Environmental Health Perspectives. December 2007, Volume 115, Number 12.][FN13: Jonathan 

Chevrier, Brenda Eskenazi, Asa Bradman, Laura Fenster, Dana B. Barr. Associations between 

Prenatal Exposure to Polychlorinated Biphenyls and Neonatal Thyroid-Stimulating Hormone Levels 

in a Mexican-American Population, Salinas Valley, California. Environmental Health Perspectives. 

October 2007. Volume 115, Number 10.][FN14: Mary E. Turyk, Henry A. Anderson, Victoria W. 

Persky. Relationships of Thyroid Hormones with Polychlorinated Biphenyls, Dioxins, Furans, and 

DDE in Adults. Environmental Health Perspectives. August 2007, Volume 115, Number 8][FN15: 

June-Soo Park, Linda Linderholm, M. Judith Charles, Maria Athanasiadou, Jan Petrik, Anton Kocan, 

Beata Drobna, Tomas Trnovec, Åke Bergman, Irva Hertz- Picciotto. Polychlorinated Biphenyls and 

Their Hydroxylated Metabolites (OH- PCBs) in Pregnant Women from Eastern Slovakia. 

Environmental Health Perspectives Volume. January 2007, 115, Number 1.]. 

The background levels of those substances found in NHANES 2001-2002 are in this range and, as 

mentioned, a relationship between some with THs was also found in other NHANES data based 

studies (see ref. 6; ref.7-11 based on other datasets, show similar levels). This is in stark contrast to 

the four orders of magnitude difference between the effect level of perchlorate on THs known from 

the body of the literature and the perchlorate levels that were related to THs found in the Blount 

study. 

These contaminants appear to be part of a wider ubiquitous contaminant pool, natural and 

manmade, in which there are all kind of GCs acting with all kind of mechanisms that influence TH 

levels and thyroid function. Most seem to be linked, but additional study would be required to fully 

understand their complex relationships with one another and with TH. For more information about 

relationships between GCs, see Appendix 2. 
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Conclusion 

Suggesting that a downstream effect (TH level changes) is caused by a substance (perchlorate) 

without controlling for other relevant substances and at the same time neglecting to check whether 

that same substance has a link with a known upstream effect (iodine uptake inhibition) is not the 

basis of sound science. On the other hand, looking for the most likely causes of an effect (rather 

than a results-oriented approach seeking only to demonstrate a connection between perchlorate and 

TH) should produce more plausible leads. When comparing the data and the circumstantial 

evidence, those leads point towards a vast pool of goitrogenic compounds, both natural and 

synthetic, of which the perchlorate background only appears to be a marker most probably through 

the chlorine link. 

Response: See response to comment ID 28715 under comment 2600. See also response to 

comment IDs 28529 and 28551 under comment code 2500. EPA is aware of the occurrence of 

perchlorate in some sources of hypochlorite/hypochlorous acid. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0647 

EPA Comment ID: 28720 

EPA Comment Code: 2600 

Comment: Appendix 2 

The further development of the possible link perchlorate--organohalogens--TH 

* Starting from an example: pp-DDE (dichlorodiphenyldichloroethylene) is a chlorinated pesticide 

while on the other side bromides are soil disinfectants that form organobromides which are 

goitrogenic substances[FN19: Johan Maervoet, Griet Vermeir, Adrian Covaci, Nicolas Van 

Larebeke, Gudrun Koppen, Greet Schoeters, Vera Nelen, Willy Baeyens, Paul Schepens, Maria K. 

Viaene. Association of Thyroid Hormone Concentrations with Levels of Organochlorine 

Compounds in Cord Blood of Neonates. Environmental Health Perspectives. December 2007, 

Volume 115, Number 12.]. So, both of those persistent organohalogens are often found together. 

* Further, when bromine (a water disinfectant just as chlorine) and chlorine are involved, 

halogenated furanones can be produced by the reaction of naturally occurring organic matter and 

bromide with the disinfectant chlorine and chloramine. Research on their concentrations in drinking 

water is at an early stage and they are not regulated by EPA: 

http://pubs.acs.org/cen/news/86/i13/8613news7.html 

[Clarification: A furanone is a furan where the H is substituted with Cl, becoming polychlorinated 

furanones or polychlorinated dibenzofuranones. A furan is short for dibenzofuran; a chlorinated 

dibenzofuran is a PCB with a furan ring in the middle]. 

* This shows their common link with PCBs. Therefore, the halogen bromine can join the second 

pathway for chlorine: From bleach/Cl2/ Cl2/Cl-/chloramine, bromides ->-> furanones or phenols 
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->-> organohalogens /Dioxins. Thus all those persistent GCs are mostly related qualitatively and 

quantitatively with each other and apparently related with perchlorate. 

* Associations between NHANES 2001-2002 data for pp-DDE versus TSH and perchlorate versus 

TSH illustrate the following: - Association between pp-DDE and TSH, total population: significant 

(p=0.0185) - Association between perchlorate and TSH, total population: not significant (p> 0.05). - 

Association between pp-DDE and TSH, women: significant (p= 0.0040) - Association between 

perchlorate and TSH: women < 100 ug UI, significant (p= 0.001) - Association between perchlorate 

and TSH: women > 100 ug UI, significant (p= 0.0249). 

Conclusion: pp-DDE and other organo-halogens all seem to be related to each other and with 

perchlorate within the goitrogenic pool. 

Further, we performed some additional analyses on pp-DDE and found the following additional 

relationships or outcomes when investigating the association between pp-DDE and TSH: 1. There 

was no interaction between pp-DDE and iodine and gender, which is consistent as it is expected in 

the case of a non-NIS goitrogen 2. There was no interaction between gender and iodine 3. There 

was no interaction between iodine and pp-DDE, which is consistent as it is expected in the case of a 

non-NIS goitrogen 4. There was no effect of iodine on TSH, which is consistent as it is expected 

(see ref. 6). 5. After correcting for pp-DDE, an increase of perchlorate was associated with an 

increase of TSH, only for females (p=0.0003). 6. After correcting for perchlorate, an increase of ppDDE was associated with an increase of TSH, only for women (p=0.004). 

Conclusion: The relation of those organohalogens with TSH seem to be consistent with an effect 

not depending on iodine levels, contrary to the perchlorate and other NIS goitrogen relations with 

TSH in the Blount study which are inconsistent not only with an iodine dependent effect but also 

show an inconsistent effect between each other. 

* Some components of this goitrogenic contaminant pool have a stimulatory or agonistic effect, 

others an inhibitory or antagonistic effect[FN20: Cornelia Schmutzler, Inka Gotthardt, Peter J. 

Hofmann, Branislav Radovic, Gabor Kovacs, Luise Stemmler, Inga Nobis, Anja Bacinski, Birgit 

Mentrup, Petra Ambrugger, Annette Gruters, Ludwik K. Malendowicz, Julie Christoffel, Hubertus 

Jarry, Dana Seidlova-Wuttke, Wolfgang Wuttke, Josef Kohrle. Endocrine Disruptors and the 

Thyroid Gland-A Combined in Vitro and in Vivo Analysis of Potential New Biomarkers. 

Environmental Health Perspectives. December 2007, Volume 115, Number S-1.][FN21: 

http://www.ourstolenfuture.org/Basics/chemlist.htm]. Some do not have any effect at all at 

environmental doses. This may explain why in cross sectional studies as those based on the 

NHANES data base the effect of the sum of some PCBs apparently is not always greater than each 

individual effect as would be expected[FN22: Kevin M Crofton, Elena S Craft, Joan M Hedge, Chris 

Gennings, Jane E Simmons, Richard A Carchman, W Hans Carter, Jr., Michael J Devito. Thyroidhormone-disrupting chemicals: evidence for dose-dependent additivity or synergism. 

Neurotoxicology Division, National Health and Environmental Effects Research Laboratory, Office 

of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, 

North Carolina, USA. Environ Health Perspect. 2005 Nov ;113 (11):1549-54 16263510 (P,S,G,E,B).] 

as each individual PCB on itself can be linked to other non identified and quantified goitrogens i.e. 

(once again) not controlled for covariates with opposite effects. 
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* As mentioned, there already exist 209 known congeners of PCBs alone. They vary based on the 

number and positions of chlorine atoms but also on their effect (strength and direction). Many have 

not even been studied on their goitrogenic effect. The fact that the few that were studied, here and 

in other studies, were found to be predictors of TSH levels is so much the more remarkable. 

* Even different groups of chemicals with different mechanisms could have synergetic or 

antagonistic effects[FN23: Andreas Kortenkamp. Ten Years of Mixing Cocktails: A Review of 

Combination Effects of Endocrine-Disrupting Chemicals. Environmental Health Perspectives, 

December 2007, Volume 115, Number S-1.]. 

* Others may be linked to each other in certain environments and not in others. For example 

Polychlorinated Biphenyls (PCBs) and Polybrominated Diphenyl Ethers (PBDEs) --both also called 

polyhalogenated phenolic compounds-- may have a cumulative effect where bromine and chlorine 

based disinfectants are used (for example for swimming pools) and end up as DBPs (disinfection byproducts) in drinking water after having gone thru the purification plant. This link could not exist in 

places where one of both is not used. 

* Other goitrogenic phenols, such as Bisphenol A, linked itself to polyvinylchloride (PVC) such as 

used in waterpipes, may be linked to this chloride and halogen pool. 

* On the other side completely different types of GCs, even natural ones, could be linked indirectly 

to the pool as well: for example organohalogen based pesticides may be present in very low amounts 

in soybeans but the goitrogenic effect could instead be primarily due to the isoflavones naturally 

present in soymilk[FN24: Daniel R. Doerge, Daniel M. Sheehan. Goitrogenic and Estrogenic 

Activity of Soy Isoflavones. Environmental Health Perspectives Supplements. June 2002, Volume 

110, Number S3.] or the thiocyanates present in rape or broccoli or other natural goitrogens such as 

genistein, resveratrol, silymarin, linuron[FN25: Environmental Protection Agency, EPA/600/P03/002F).An Inventory of Sources and Environmental Releases of Dioxin-Like Compounds in the 

United States for the Years 1987, 1995 and 2000. Federal Register: December 1, 2006 (Volume 71, 

Number 231)] Page 69564-69565] Health Perspectives Supplements. June 2002, Volume 110, 

Number S3.] 

* Also fluorine is considered a goitrogen[FN26: Fluoride in Drinking Water: A Scientific Review of 

EPA's Standards (NAS, 2006) http://www.iicph.org/docs/water- reg-20060830.htmhttp:// 

www.pubmedcentral.nih.gov/articlerender.fcgi?artid=476957]. So, adding fluorine in salt for dental 

purposes could partially neutralise the effect of added iodine. Adding fluorine, another halogen, in 

drinking water, which is also common, would then on itself be linked to perchlorate and the 

organohalogen DBPs. 

* Further fluorine is a major constituent of phosphate fertilizers[FN27: 

http://fluoridealert.org/phosphate/overview.htm#2] and is taken up by the crop so it could, just as 

the goitrogenic pesticides and isoflavones, be part of the goitrogenic pool as well. Also iodine itself, 

the fourth halogen, is used as a disinfectant. 

* Other factors, even the most unexpected (birth delivery mode) may confound the effects[FN28: 

Julie B. Herbstman, Andreas Sjodin, Benjamin J. Apelberg, Frank R. Witter, Rolf U. Halden, Donald 

G. Patterson Jr., Susan R. Panny, Larry L. Needham, and Lynn R. Goldman. Birth Delivery Mode 

Modifies the Associations between Prenatal Polychlorinated Biphenyl (PCB) and Polybrominated 
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Diphenyl Ether (PBDE) and Neonatal Thyroid Hormone Levels. Environmental Health 

Perspectives. October 2008, Volume 116, Number 10.]. 

* And finally the fact that "The R2 value of 0.061 reported by Blount et al. (2006a) for the 

association between TSH, perchlorate, and other significant covariates for lower-iodine women 

indicates that perchlorate accounts for only about 1% of the variation seen for TSH in that 

population"(quote extracted from ref.6.1) and that therefore about 99% is related directly to 

goitrogenic compounds once again strongly supports the role of perchlorate as a marker only and 

not a cause. 

Response: EPA cannot evaluate materials that have not been peer reviewed. 

See response to comment ID 28715 under comment 2600. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0647 

EPA Comment ID: 28721 

EPA Comment Code: 2600 

Comment: Appendix 3 

Based on the principle of competitive uptake inhibition, it is impossible that perchlorate would have 

caused the TH changes found in the Blount et al, 2006 study 

According to Tonacchera et al., Thyroid, 2004[FN29: Office of Inspector General Scientific Analysis 

of Perchlorate ,Assignment No. 2008-0010, December 30, 2008] 

RAIU= 1.22 / (1.22 +PEC) 

Where PEC =serum perchlorate equivalent concentration = [ClO4_] + [SCN_] / 15 + [I_] / 30 + 

[NO3_] / 240 = serum perchlorate + thiocyanate/15+ iodine /30 + nitrate concentration/240 and 

RAIU = Radioactive Iodine Uptake. 

All concentrations are in umol. 

The model is only valid for this specific lab trial set-up as described in Tonacchera et al., 2004 but 

has been generally accepted. 

Assume that PEC A is a serum perchlorate equivalent concentration equal to A and PEC B is a 

serum perchlorate concentration equal to B. 

From the above equation it follows that if PEC A is < PEC B the RAIU, which is the incremental 

iodine uptake, is larger for PEC A than for PEC B. 

This then also means that, if there is no iodine inhibition for a certain level B of PEC in human 

serum, there will not be any iodine uptake inhibition for a level A of PEC in human serum either, if 

PEC A 
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(Note that PEC includes here the iodine level as iodine itself is an iodine uptake inhibitor. Indeed 

the more iodine present the more the uptake of the added (incremental) dose of iodine (marked here 

with radioactive iodine) will be inhibited and therefore the less (radioactive) iodine of the dose will 

be taken up). 

Further, since we assume steady state (see note below), perchlorate, SCN, iodine and nitrate urinary 

levels are proportional to perchlorate, SCN, iodine and nitrate effective serum levels or in other 

words if PEC is, for example, double in serum of person B compared to PEC in serum of person A 

(ceteris paribus) we can assume that urinary PEC of person B will be double the urinary PEC of 

person A and vice-versa. 

Note: We quote: "In all risk assessments on perchlorate iodine uptake inhibition "The central 

assumption is that the amount of perchlorate excreted per day equals the amount ingested in the 

bio-monitored individuals. This is true if these individuals are near or at steady state."(See: 

Evaluation of the U.S. EPA/OSWER Preliminary Remediation Goal for Perchlorate in 

Groundwater: Focus on Exposure to Nursing Infants ,Gary L. Ginsberg,1 Dale B. Hattis,2 R. 

Thomas Zoeller,3 and Deborah C. Rice.(ehp, Dec. 2006). 

If perchlorate risk assessments are based on this assumption there is no reason why the same 

assumption could not be adopted here. 

Also we can say that the segment of the general US population with an average of around 200 ug/l 

urinary iodine, which is well above the minimum WHO (World Health Organization) recommended 

level of 100 ug/l UI is on average not exposed to any iodine uptake inhibition and to such a level of 

inhibition as to cause TH (Thyroid Hormone) changes. 

Hence, if using the Tonacchera RAIU equation but with urinary PEC instead, the segment of the US 

population with an average of 200 ug/l U iodine and with an average U PEC B has no overall iodine 

uptake inhibition, then we can deduct that the segment of the US population with for example an 

average of 30ug/l U iodine (thus iodine level B>A) but with a PEC A < PEC B and therefore a 

larger incremental uptake of (radioactive) iodine, does not have any iodine uptake inhibition as well. 

We found that U PEC (as defined above) of the 1/8 segment of NHANES 2001-2002 female 

population with the average of 228 ug/l UI was higher than the U PEC of the 1/8 segment of 

NHANES 2001-2002 female population with the lowest average of 31ug/l UI (and also higher than 

that of the subsequent higher segments), See following table1: U PEC is called TGL (total (NIS) 

goitrogen load) here. 

Table1: NHANES 2001-2002: Relationship between urinary iodine and TGL (sorted for iodine) [see 

PDF docket ID EPA-HQ-OW-2009-0297-0647] 

Indeed, when applying the Tonacchera equation after converting molar concentrations into 

concentrations expressed in weight we have for women B with urinary iodine average of 228 ug/l 

(n=1109/8= 139) (See table 1 above, col.1 ): 

RAIU-B i= 1.22 / (1.22 +PEC) where PEC = [ClO4-] + [SCN-] / 8.8 + [I-] / 38 + [NO3-] / 150) 
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= 1.22 / (1.22 + 5.9+2205/8.8+228/38+74567/150) =1.22/(1.22 

+5.9+251+6+497)=1.22/(1.22+760) =1.22/761.22 =0.0016 

And for women with iodine average of 31 ug/l (n=1109/8= 139) (see table 1 above, col.1). 

RAIU-A = 1.22 / (1.22 +1.5+967/8.8+31/38+19293/150) = 1.22 / (1.22 +1.5+110+0.8+129) = 

1.22 / 242 =0.005. 

Thus RAIU-A is about 3 times larger than RAIU-B which means that the incremental iodine uptake 

inhibition for A women with urinary I =31 ug/l has to be less than for B women with I = 228 ug/l. 

This is due to the substantially higher total goitrogen load of women with the higher iodine level; see 

following tables 2, 3 and 4 

Table 2, iodine insufficient women ( <100ug/l UI): col. 9 : total goitrogen load(TGL) is about half 

and each of the 3 NIS goitrogens nitrate(col. 5), thiocyanate (SCN, col.7) and perchlorate (col.8) are 

about half of TGL for iodine sufficient women ( >100ug/l UI, table 3) and for the total population 

(table 4)or in other words women with sufficient iodine have about double the NIS goitrogen 

load.[see PDF docket ID EPA-HQ-OW-2009-0297-0647] 

Since, as mentioned, B women (228 ug/l UI) are not exposed to iodine uptake inhibition, A women 

(31 ug/l UI) should not be exposed to iodine uptake inhibition either and therefore TH levels could 

not be affected by the goitrogen load (of which perchlorate only represents 1%). In other words, 

since we can confidently assume that NIS goitrogen load does not affect iodine uptake in the 

NHANES 2001-2002 women with mean iodine levels of 228 ug/l urinary iodine it follows from 

above calculations that NIS goitrogen load, and a fortiori perchlorate load which only represents 1% 

of this load, does not affect iodine uptake and a fortiori TH levels in NHANES 2001-2002 women 

with the lowest iodine levels of only 31 ug/l. as a mean. 

Conclusion 

Based on the above analysis of goitrogen levels, iodine uptake and using the Tonacchera equation, it 

is not possible that the ability of urinary perchlorate to significantly predict TH changes in women 

with urinary iodine less than 100 ug/L reported by Blount et al., 2006, is directly associated with the 

joint goitrogen effect of nitrate, perchlorate and thiocyanate. Thus, it is not possible that the 

association is directly connected to perchlorate alone. More likely, the higher goitrogen load of 

iodine sufficient women is related to a healthier diet, one rich in vegetables and fruit. 

Response: EPA cannot evaluate calculations that have not been peer reviewed. 

Commenter Name: Nsedu O. Witherspoon 

Commenter Organization: Children's Environmental Health Network 

EPA Document ID: EPA-HQ-OW-2009-0297-0674 

EPA Comment ID: 28739 

EPA Comment Code: 2600 

Comment: EPA must also consider other exposure pathways and additional contaminants 

in the environment that impact thyroid function when establishing the MCL. Studies of perchlorate 

levels in food, including breast milk, show that the population is exposed through multiple pathways 
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in addition to contaminated drinking water. EPA should determine potential aggregate exposures 

based on a broad range of contamination levels, and not just the mean, which was the basis for 

current estimates. While data have also demonstrated a particular threat to the significant number of 

individuals, especially women of child bearing age, who are iodide deficient, the current modeling 

does not include this threat. 

Given this widespread problem (CDC estimates up to 30% of women do not get sufficient 

dietary iodide), it is critical to take into consideration the potential for exposure to other thyroidactive agents. Consequently, EPA must consider the cumulative impact of perchlorate, other 

substances in the environment that inhibit the uptake of iodide by the thyroid, and inadequate 

supplies of iodide in American diets, all of which makes a stringent drinking water standard 

necessary to be truly health protective. 

Response: EPA will consider a variety of sources of perchlorate in developing the 

NPDWR. 

As demonstrated in the in the August 2009 Supplemental Request For Comments, breast fed infants 

is a group identified by EPA as of interest. 

See response to comment ID 28529 under comment code 2500. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28804 

EPA Comment Code: 2600 

Comment: Other contaminants are known to also interfere with iodide uptake via a similar or 

identical mechanism. For example, the widespread water contaminant, nitrate has a shared 

mechanism of action as does the chemical thiocyanate, found in cigarette smoke and in some 

foods.[FN44: Ginsberg G and D Rice. The NAS perchlorate review: questions remain about the 

perchlorate RfD. Environ Health Perspect. 2005 Sept; 113(9):1117-9. Erratum in: Environ Health 

Perspect. 2005 Nov; 113(11):A732.] There is some indication in the CDC data analyzed by Blount et 

al. that nitrate may be a factor in the modulation of thyroid hormone status. An independent analysis 

by OEHHA staff found an interaction between perchlorate and thiocyanate exposure and tobacco 

smoke exposure on thyroid hormone. It is also known that perchlorate and thiocyanate are found in 

breast milk.[FN45: Kirk, AB, Dyke JV, Martin, CF, Dasgupta PK. 2007. Temporal patterns in 

perchlorate, thiocyanate, and iodide excretion in human milk. Envrion Health Perspect.115(2):182-

6.] 

Response: See response to comment ID 28529 under comment code 2500. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0227 

EPA Comment ID: 28817 

EPA Comment Code: 2600 

Comment: Water Docket ID No, EPA - HQ - OW - 2009 - 0297 : comments 
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Perchlorate: The Greer Non Observed Effect Level (NOEL) and the NAS Reference Dose (RfD) 

are significantly inaccurate and do not provide a defensible basis for regulation 

By: Herwig Opdebeeck, SM, Opdebeeck Consulting 

In its Perchlorate Supplemental Request for Comments, published in the Federal Register on August 

19, 2009, EPA states that its preliminary regulatory determination will be based upon the RfD and 

risk assessment derived from the 2002 Greer study. However, as discussed below, the Greer NOEL 

did not take into account background effects, including the effects of other goitrogens, and is thus 

not a true NOEL. The true NOEL is the perchlorate dose administered in the Greer study (7 

ug/kg-day), plus the dose corresponding to the background effect. The fact that this background 

level has not been added and is not taken into account, leads to a fundamental flaw in the 

perchlorate risk assessment and should not be relied upon to either regulate perchlorate or establish 

an RfD . 

Response: EPA disagrees. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0227 

EPA Comment ID: 28819 

EPA Comment Code: 2600 

Comment: Indeed, analyzing the NHANES database, we found that the perchlorate NOEL -- 

identified in the Greer study as the point at which the slightest decrease in iodine uptake occurs -- is 

not 7 ug /kg-day, but 157 ug /kg-day absent any perchlorate or perchlorate equivalent background 

level in the Greer cohort (which is assumed to be representative for the US population). 

Second, and perhaps more significantly, even though the level of background perchlorate is low, 

other goitrogens in the environment represent a very significant perchlorate equivalent background, 

22 times more potent than the Greer NOEL and more than 2,200 times more potent than the 

perchlorate background level itself for the general population (for women with insufficient iodine 

(<100 ug UI) the total goitrogen load and perchlorate background are about half, see study 

addendum 1. This should reflect on the goitrogen level in general and the perchlorate level in 

particular of foetuses and breast-fed neonates). This perchlorate equivalent background mostly 

consists of thiocyanate and nitrate in food and water. 

Therefore, the true NOEL is the Greer apparent NOEL + the background perchlorate equivalent 

level (PEC) and is, at 157ug/kg-dayPEC, 22 times larger than the apparent Greer NOEL of 7 ug 

/kg-day. This leads to a PEC RfD of 15.7 ug/kg-day instead of the NAS RfD of 0.7 ug/kg-day. 

This background level should be taken into account in evaluating whether regulation of perchlorate 

through the Safe Drinking Water Act would result in a meaningful opportunity for health risk 

reduction for persons served by public water systems, and in determining what constitutes a level of 

public health concern. For the reasons discussed below, regulation of perchlorate would not achieve 

either of these goals, because the effect on iodine uptake (the basis for the NOEL) resulting from 

perchlorate in public drinking water systems is inconsequential in comparison to the effect of other 

substances on iodine uptake. Due to the significant impact of these substances on iodine uptake, 
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even the elimination of perchlorate from the drinking water supply would result in (at best) only a 

negligible improvement in iodine uptake, and would have no effect on overall public health. If the 

purpose of the PHG is to be truly health protective, the perchlorate equivalent drinking-water PHG 

would need to be shared with those other goitrogens. For drinking-water, that would mean that the 

perchlorate PHG would need to be shared with the existing nitrate MCL. 

Applying a default relative source contribution (RSC) of 20%, and assuming that the goal is to avoid 

the slightest iodine uptake inhibition caused by perchlorate and/or nitrate, we come to the 

conclusion that, even using the much higher NOEL level discussed above, to achieve the intended 

effect of the PHG, the MCL for nitrate would need to be drastically lowered (by more than 80 % if 

the perchlorate PHG were between 0 (zero) and 1 ppb and by more than 75% if the PHG were to 

be 15 ppb) and the vegetable and fruit intake of a large segment of the US population (all of the 

population with a balanced diet) would need to be limited to the daily consumption of fruit and 

vegetables equivalent to the nitrate content of 2.3 ounces of lettuce or equivalent to the thiocyanate 

+ nitrate content of an even smaller amount of broccoli. 

The logical conclusion of this analysis indicates that either the nitrate MCL is too high to avoid 

iodine uptake inhibition, or a NOEL based on iodine uptake inhibition is not an appropriate effect 

on which to base a PHG for perchlorate. Because foods containing nitrate and thiocyanate are an 

integral part of a healthy diet, and the effects on iodine uptake can be countered by adequate levels 

of iodine in the diet, logic dictates the latter conclusion. 

This logical conclusion is further supported (if support would still be needed) by the fact that, as 

mentioned before; i) for women with insufficient iodine (<100 ug UI) the total goitrogen load and 

perchlorate background are about half, see study addendum 1; ii) according to the same NHANES 

database, urinary iodine is strongly and positively associated with urinary perchlorate which means 

that the more there is perchlorate background exposure the more there is background iodine 

exposure (see study addendum 2). 

Response: See response to comment IDs 28529, 28551, and 20523 under comment code 2500 

EPA cannot evaluate calculations that have not been peer reviewed. EPA believes the nitrate 

NPDWR appropriately derived. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0227 

EPA Comment ID: 28821 

EPA Comment Code: 2600 

Comment: 1.2. Determination of the background adjustment factor, BAF 

1.2.1. Epidemiological studies: Quantitative Observational Study versus Experimental Study 

In order to arrive at an RfD, an effect level is normally determined. The effect level is determined by 

means of epidemiological studies. By far the most common type of human epidemiological study is 

the quantitative observational study, which is one of the two that leads to dose-response information 

[FN3: R.L. Calderon ,The Epidemiology of Chemical Contaminants of drinking Water , US EPA, 

Food and Chemical Toxicology, 38, 2000.] (and which cannot be controlled for substances that have 
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not been measured). The other type is the controlled experimental study and is typically used to 

evaluate drugs or vaccines, but is seldom used to evaluate environmental contaminants.[FN3: R.L. 

Calderon ,The Epidemiology of Chemical Contaminants of drinking Water , US EPA, Food and 

Chemical Toxicology, 38, 2000.] 

The quantitative observational study is in fact a dose-response study of the background level of the 

contaminant (which in the case of perchlorate is assumed to be food and drinking water). This is not 

the case of an experimental study, where the dose-response of the administered dose is studied and 

not that of the background level. This type of study instead presumes that the background level of 

the substance is zero, and that the only cause of the effect of the substance in the bodies of the 

subjects is the administered dose of the substance. 

Therefore, in an experimental study such as the Greer study, the effect level that would be found 

through such longitudinal experiment would not be the true effect level. Instead, the true effect level 

would be the sum of the administered dose and the background effect level. The Greer 2002 study 

from which the RfD was derived was such an experimental study, and the background perchlorate 

exposure level may have been confused with the administered dose or may simply have been 

overlooked. Indeed, experimental clinical studies on humans are, for obvious reasons, seldom done 

in order to estimate the dose- response of environmental contaminants. The Greer 2002 trial, 

however, had as its endpoint a Non Observable Effect Level, which was considered a non adverse 

effect level. This trial was, therefore, an inappropriate method to effectively determine the NOEL. 

1.2.2. NIS Iodine uptake inhibitors have a cumulative effect 

Normally the (adverse) effect level of each contaminant is established independently from other 

contaminants, as most toxins have a specific effect, their effect is not cumulative at all levels, or their 

cumulative effect is simply not well known. However, this is not the case for the NIS competitive 

iodine uptake inhibitors, or goitrogens, whose mode of action is well known and is known to be 

cumulative. Particularly for the three major goitrogens-- nitrate, perchlorate and thiocyanate -- their 

simple cumulative effect and their relative potency are well known. Thus, in the case of the Greer 

study, the background level is the perchlorate background level, plus the level of other goitrogens 

with the same mode of action, i.e. the (competitive) inhibition of iodine uptake. 

1.2.3. The Background Adjustment Factor BAF 

Indeed, the Greer participants did have additional perchlorate doses through background food and 

drinking water perchlorate as well as background perchlorate equivalent caused by other goitrogens. 

This means that the NOEL from the Greer experimental study and which we call Greer_NOEL is 

lower than the real NOEL which we call PEC_NOEL (Perchlorate Equivalent Concentration 

NOEL) with PEC_NOEL = Greer_NOEL x BAF (Background Adjustment Factor) and with 

BAF>1. 

1.2.3.1. The perchlorate background adjustment 

The median perchlorate background exposure in the US adult population is 4.6ug/day,[FN4: Blount 

BC, Valentin-Blasini L, Osterloh JD, Mauldin JP, Pirkle JL, 2006a. Perchlorate Exposure of the U.S. 

Population, 2001-2002. Journal of Exposure Science and Environmental Epidemiology, 1-8.] which 

is 0.066 ug/kg-day representing only 0.9 % of Greer- NOEL. Thus the mean total perchlorate 
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exposure of the Greer cohort = 7 ug/kg-day + 0.066 ug/kg-day = 7.07 ug/kg-day which for all 

practical purposes we round off and keep at 7 ug/kg-day. 

It is worth noting here that the cross-sectional Blount et al, 2006 background study [FN5: Blount 

BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell L, 2006b. Urinary Perchlorate and Thyroid 

Hormone Levels in Adolescent and Adult Men and Women Living in the United States. 

Environmental Health Perspectives 114(12): 1865-1871.] showed a weak but statistically significant 

relationship of this very low background exposure with an effect, and even more surprisingly a 

downstream adverse effect only. This same significant adverse effect relationship, however, is also 

shown to exist with the background level of some organo halogens in the same NHANES database 

but which are known, contrary to perchlorate, to cause that kind of weak adverse effect at such low 

levels. 

1.2.3.2. Other goitrogen background adjustment 

In addition, the Greer trial participants were exposed to a perchlorate equivalent background in food 

and drinking-water from the goitrogens thiocyanate (SCN), nitrate (NO3-) and other goitrogens 

affecting iodine uptake into the NIS such as fluoride, chlorate and several others. For practical 

purposes we will only take nitrate and thiocyanate into account as those two are the most important 

and best documented goitrogens (Michael Zimmermann, European Thyroid Association (ETA) 

Symposium, Lisbon, September 9, 2009). 

In the US adult population, serum background exposure to nitrate expressed in serum perchlorate 

equivalent concentration (SPEC) is estimated at 0.167umol/l and that of thiocyanate at 1.333umol/l 

for a total of 1.567umol/l compared to a serum Greer_NOEL for perchlorate estimated at 

0.070umol/l.[FN6: See Office of Inspector General Scientific Analysis of Perchlorate ,Assignment 

No. 2008-0010, December 30, 2008, page 84 and 85 (goitrogen serum and urinary levels based on 

the NHANES 2001-2002 dataset).] Thus, perchlorate serum exposure of 0.070 umol/L at the Greer 

NOEL dose represents only 4.5 % of the total serum goitrogen load of 1.567umol/L or in other 

words the perchlorate equivalent concentration NOEL, PEC_NOEL, which is the real NOEL, is 

22.4 times larger than the Greer_NOEL(which itself is more than 100 times larger than the 

perchlorate background). PEC_NOEL = Greer_NOEL x BAF= Gr_NOEL x 22.4 = 157 ug /kgday where BAF is a perchlorate equivalent BAF. 

The Greer NOEL of 7ug/kg-day is not a true NOEL but a NOEL on top of the much larger (i.e. 

21 times larger) perchlorate equivalent background level. Therefore, the true NOEL is the Greer 

apparent NOEL, plus the background equivalent perchlorate level, and is more than 22 times larger 

than the apparent Greer NOEL of 7 ug /kg-day. The background exposure level of perchlorate 

itself, however, is negligible as it is more than 100 times smaller than the Greer NOEL or more than 

2,200 times smaller than the true NOEL, taking into account only the most well-known goitrogens. 

1.2.4. The true reference dose RfD 

The true RfD is obtained by dividing the true NOEL by UF (uncertainty factor) which NAS set at 

10. Thus the true RfD or PEC_RfD = PEC_NOEL/UF = 157ug/kg-day /10 = 15.7ug/kg-day, 

equivalent with the ingestion of 2 litres of 550 ppb perchlorate drinking-water if there were no other 

goitrogen exposure from drinking-water, food and any other source. 
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1.2.5. From the true RfD to Perchlorate Equivalent Concentration PHG 

To derive a PHG (Public Health Goal) or MCL (Maximum allowed Contaminant Level) for 

drinking-water from an RfD, usually a RSC (Relative Source Contribution) is applied. 

Assume that 80% of perchlorate + nitrate + thiocyanate background originate from food and 20% 

from drinking-water. A 20 % RSC is the lowest and most conservative RSC used in the derivation of 

a maximum contaminant level goal [FN7: Regulatory Determination Support Document for selected 

Contaminants from the second Drinking Water Contaminant Candidate List (CCL-2), US-EPA 

report 815-D-06-007, December 2006.]. It is the minimum default value. 

If no other goitrogens were present in drinking-water, the PHG would then be: 15.7 ug/kg-day x 

70kg/2Lx 0.20= 110 ppb or again 22 times the 5 ppb proposed by for example NJ Department of 

the Environment which used the same 20 %RSC [FN8: 

http://www.nj.gov/dep/watersupply/perchlorate_mcl_10_7_05.pdf]. 

1.2.6. The perchlorate-only PHG in relation to the total perchlorate-equivalent PHG 

If other goitrogens are present, a PEC_PHG (i.e. the total perchlorate equivalent PHG) should be 

shared with those other goitrogens. This approach is the only sensible approach, as no distinction 

between the goitrogens can be made if the goal of the MCL is to be health protective. 

For drinking water, nitrate would be the most significant other goitrogen. If the current nitrate MCL 

were taken into consideration, then PEC_PHG should be equal to PHG of perchlorate + MCL of 

nitrate expressed in PEC (Perchlorate Equivalent Concentration)[FN9: Nitrate PEC = [nitrate]/240 

when expressed in molar weight and /150 when expressed in weight: De Groef B, Decallonne BR, 

Van der Geyten S, Darras VM, Bouillon R, 2006. Perchlorate Versus Other Environmental 

Sodium/iodide Symporter Inhibitors: Potential Thyroid-related Health Effects. Eur J Endocrinol 

155(1):17-25.]. 

As mentioned, the combined perchlorate + equivalent nitrate maximum level should be< 110 ppb 

or ([Nitrate] PEC+ [perchlorate] should be <110 ppb. Since the nitrate MCL = 44 ppm nitrate or 

44,000/150ppb=293 ppb PEC, PE_PHG should be equal to PHG perchlorate + 293ppb. Hence, 

PHG perchlorate should be equal to 110 ppb-293 ppb= negative 183 ppb, which is of course not 

possible.[FN10: Note: if an RSC =1, as was the case for the nitrate MCL, would have been applied 

on the background perchlorate equivalent level as well, PEC_PHG would have been = (15.4 ug/kgday) x 70kg/2 l x 1= 539 ppb. Indeed in determining the drinking water nitrate MCL no RSC (i.e. 

RSC=1) taking into account food has been applied even though nitrate levels in food such as 

vegetables are very significant (and as much significant in terms of BBS as iodine uptake 

inhibition).If this would have been done, it would on itself already have lowered substantially the 

nitrate MCL. A 0.2 default value, as we apply here for PEC, would have lowered it already to 8.8 

ppm. According to the WHO (see ref. 12) the contribution of drinking-water to nitrate intake is 

usually less than 14 so even lower than the conservative 20 % default value assumed here.] 

Thus, we must conclude that either the nitrate MCL is too high to avoid iodine uptake inhibition, or 

a NOEL based on iodine uptake inhibition is not an appropriate effect on which to base a PHG for 

perchlorate -- or both. If, nevertheless, the iodine uptake inhibition NOEL is to be kept as the 
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relevant effect, the nitrate MCL should be lowered in the first instance from 44 to 14.2 ppm to allow 

a perchlorate PHG of for example 15 ppb, the one EPA currently proposes as an interim level. 

There is an additional background adjustment, another RSC, to be made for nitrate. Contrary to 

perchlorate and thiocyanate for which the serum exposure is proportional to the oral exposure, there 

is, besides an oral exposure, also an endogenous exposure to nitrate estimated at 45% of total nitrate 

exposure.[FN11: Nitrate and Nitrite in Drinking Water, Subcommittee on Nitrate and Nitrite in 

Drinking Water, Commission on Life Sciences, NRC (National Research Council), page 38. 

Washington, DC, National Academy Press, (ISBN-10: 0-309-08370-2).] Therefore there is an 

estimated relative source contribution of exogenous (oral) nitrate of 55% only. Thus to allow a 

perchlorate PHG of 15 ppb the nitrate MCL should be further lowered to 14.2 x 0.55= 7.8 ppm 

nitrate (or 2.1 ppm N as nitrate instead of 10 ppm N as nitrate) or about 1/5 of the current MCL). 

(This cannot be significantly compensated for by further lowering the perchlorate PHG from 15 to 

1ppb (a 93% decrease), since this would only allow an increase of the nitrate MCL from 7.8 ppm to 

a still very low 9.9 ppm( a 27% increase only), still ending up with less than 1/4 of the MCL). 

So, even with a PEC of 110 ppb (based on a true RfD of 15.5ug/kg-day PEC and a RSC of 20%), it 

is obvious that either the nitrate MCL (=293 ppb PEC) is too high to avoid iodine uptake inhibition 

or a NOEL based on iodine uptake inhibition is not an effect on which to base a PHG for 

perchlorate, or both. 

Further, since we used a 20% default RSC which resulted in a perchlorate + nitrate MCL of 110 ppb 

for drinking-water, this means that the perchlorate equivalent exposure through drinking-water 

would be 2 Lx 110 ug/lL = 220 ug per adult /day. This would also mean that the intake through 

food, which would represent 80%, would be 220x80/20= 880 ug per adult/day perchlorate 

equivalent. This seems high on first sight but in reality is not as it represents an ingestion of only 66 

g (2.3 ounce) of lettuce containing an ordinary 2000 ppm nitrate [FN12: Nitrate and nitrite in 

Drinking-water, Background document for development of WHO Guidelines for Drinking- water 

Quality, Originally published in Guidelines for drinking-water quality, 2nd ed. Addendum to Vol. 2 

Health criteria and other supporting information. Word Health Organization, Geneva, 1998.]; 

(Hydroponic lettuce can contain up to 6000 ppm (40,000 ppb PEC) nitrate) or an even lower 

amount of broccoli (broccoli contains a mean of 11,500 PEC nitrate and 2000 PEC 

thiocyanate).[FN13: Perchlorate, Thiocyanate, and Nitrate in Edible Cole Crops (Brassica sp.) 

Produced in the Lower Colorado River Region, C. A. Sanchez, B. C. Blount, L. Valentin-Blasini,R. I. 

Krieger, Published online: 26 October 2007, Springer Science + Business Media, LLC 2007.] 

Further, this also means that if the [perchlorate + nitrate] MCL were only 110 ppb PEC, consuming 

66 g /day of lettuce and 2 litres of 110 ppb PEC DW would already represent the maximum allowed 

daily dose though water and food and no other nitrate carriers such as spinach, melon, cured meats 

and thiocyanate carriers such as broccoli and cauliflower, (which in themselves cause an average 8 

times higher exposure load than nitrate)[FN14: Office of Inspector General, Scientific Analysis of 

Perchlorate, Assignment No. 2008-0010, December 30, 2008.] could be consumed that day by a 

healthy adult. Besides that, the nitrate level of the water consumed the same day could not exceed 

1/5 of the current MCL if a perchlorate PHG of only 15 ppb would be chosen and 1/4 if a 

perchlorate PHG of 1 ppb would be chosen, as shown above. 

Since in the US about half of the groundwater exceeds 10 ppm perchlorate and 6 % of groundwater 

exceeds 20 ppm[FN15: See ref. 12.] and almost all DW exceeds 1/5 of the MCL, the conclusion 
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should be that if a 15ppb or lower MCL for perchlorate is determined, the US population should 

basically stop consuming drinking water derived from groundwater and vegetables and fruit 

containing thiocyanates and nitrates. Even bottled water would not help much as almost all contain 

more than 5 ppm nitrate (based on a quick supermarket inquiry by the author) or 33 ppb PEC. Even 

"pristine", expensive imported bottled water contains between 3 and 10 ppm nitrate or up to 66 ppb 

perchlorate equivalent. 

Conclusion 

The NAS RfD, derived from the Greer NOEL is not a true RfD, since the Greer NOEL does not 

include the perchlorate equivalent background. The true RfD, at 15.5ug/kg-day, is more than 22 

times larger than the NAS RfD of 0.7ug/kg-day. 

Even at this higher RfD, however, the impact of other goitrogens, such as nitrate, in drinking water 

and food and thiocyanate in food would make it impossible for any level of perchlorate regulation to 

have any meaningful impact on public health. One reason for this may be that the appropriate 

"effect" to be considered in the evaluation of a NOEL should not be the point of iodine uptake 

inhibition, since the contribution of nitrate and even more of other goitrogens such as thiocyanate 

already largely exceeds the level of iodine uptake inhibition in healthy diets. Based on the foregoing, 

EPA is unable to demonstrate two of the three criteria required to regulate perchlorate in drinking 

water - namely: (1) EPA cannot demonstrate that perchlorate will occur in public water systems at 

levels of public health concern, because it cannot accurately be determined what constitutes a level 

of public health concern based on the current studies, and (2) EPA is unable to demonstrate that 

regulation of perchlorate represents a meaningful opportunity for health risk reduction for persons 

served by the public water system, since even its elimination would not result in any meaningful 

improvement in public health. 

Response: Please see the response to comment ID 28819 under comment code 2600. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0227 

EPA Comment ID: 28823 

EPA Comment Code: 2600 

Comment: ADDENDUM 1 

By: Herwig Opdebeeck, SM, Opdebeeck Consulting 

The unexpectedly weak goitrogen load of the iodine-deficient female US population 

The U.S. iodine insufficient female population, besides an inadequate iodine containing diet, seems 

to have a generally unbalanced diet characterised by a low consumption of vegetables. 

We refer again to the NHANES 2001-2002 data on urinary perchlorate (CLO4), nitrate (NO3), 

thiocyanate (SCN) and iodine where we show the relationship between iodine and total goitrogen 

load (TGL). 
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Table 1, 2, 3: NHANES 2001-2002: Relationship between iodine and total goitrogen load (TGL) 

(sorted for T4) [see PDF docket ID EPA-HQ-OW-2009-0297-0227] 

The first table is for women with <100 ug/l urinary iodine (women<100), n=384), the second for 

women with >100 ug/l urinary iodine (women>100, n= 725), the third for the total population 

(n=2080) (Individuals with >2000 ug/l urinary iodine have been removed). 

From these tables the following observations can be made: 

Preliminary note: The serum goitrogen load is a measure for the effective thyroid goitrogen load. 

Here we refer to the urinary (U) load which does not accurately reflect the effective serum load. For 

example the residence time of thiocyanate is much longer than the one of nitrate or perchlorate. 

However this does not matter here since the purpose is only to compare the urinary loads between 

the different population groups i.e. the relative loads and because we can assume that urinary loads 

are proportional to serum loads (for example a double urinary load also means a double serum load). 

-Women with iodine levels < 100 have a total goitrogen load(TGL) expressed in PEC that is about 

50% lower than women > 100 and than the overall population (columns 9 ). 

-Split into the constituents, their perchlorate, nitrate and thiocyanate levels, over the entire T4 

spectrum (Col. 2 ), are about 50%, 50% and 35% lower respectively (columns 8, 5 and 7). 

- This means that women with insufficient iodine levels happen to be those that are least susceptible 

to iodine uptake inhibition, if they would have been iodine sufficient. 

-Urinary(U) perchlorate for all population groups represents less than 1% of the total urinary 

goitrogen load expressed in PEC (columns 10) and, as shown in section 1 above, also of the total 

serum(S) load. 

Conclusion 

Women with insufficient iodine levels happen to be those that are least susceptible to iodine uptake 

inhibition, if they would have been iodine sufficient. Improving their diet and iodine uptake would 

be the remedy. 

Lowering instead the perchlorate intake by any rate (1, 10 or 100%) would not diminish NIS iodine 

uptake inhibition, also not for iodine-insufficient (<100) women since the NIS iodine uptake 

inhibition potential caused by TGL which is more than 100 times larger, is already 50 % lower than 

for iodine sufficient women (>100). So besides the fact that eliminating all perchlorate even the 

background level would still leave 99% of TGL untouched, this remaining 99% is only half that of 

iodine sufficient women. 

ADDENDUM 2 

By: Herwig Opdebeeck, SM, Opdebeeck Consulting 

The strong relationship of low levels of U-perchlorate with U-iodine levels 
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In continuation of Addendum 1 : Nevertheless women with urinary iodine < 100 ug/l have a ratio 

of iodine to total goitrogen load (TGL) equal to about 0.2/1 for every T4 octille (1/8) while women 

> 100 ug/l have about a ratio equal to 0.8/1 also for every T4 octille (columns 13 of above 2 first 

tables of addendum 1) which means that, even though the goitrogen load for iodine-insufficient 

women is only about half that for iodine sufficient women, their iodine inhibition potential is 4 

times higher so it is obvious that if iodine uptake inhibition in this subpopulation would occur it 

would be due to lack of iodine and not due to goitrogen load. 

For perchlorate this is even more explicit since perchlorate, at low levels, is strongly related to 

iodine: see next figure[FN16: 1. Charnley G, Perchlorate: Overview of Risks and Regulation. Food 

and Chemical Toxicology, 2008. 2. Soldin OP, Tractenberg RE, Pezzullo JC. Do thyroxine and 

thyroid-stimulating hormone levels reflect urinary iodine concentrations? Therapeutic Drug 

Monitoring. 2005, 27: 178-185. ] (fig.2) which is derived from the same NHANES 2001-2002 

survey. 

Fig 2 Relationship between urinary iodine and urinary perchlorate for the general population 

controlled for gender, T4 and TSH, p<0.0001 (ug/l, log scale) [see PDF docket ID EPA-HQ-OW2009-0297-0227] 

This relationship also suggests that low levels of perchlorate are naturally linked to iodine (both are 

formed in the atmosphere and both are found in naturally nitrate -rich soils in the US S-W deserts 

and arid regions). 

So women with low natural background levels of perchlorate have low natural background levels of 

iodine. For higher background levels of perchlorate the link with iodine ceases to exist or not 

enough data points exist for those higher levels. 

Thus it seems that women with higher levels of iodine not only tend to have higher levels of natural 

perchlorate but additionally some from other contaminated (point) sources. 

For the other 2 goitrogens this suggests that those iodine-insufficient women also consume 

significantly less vegetables than the iodine-sufficient population. This could then also explain the 

higher non-natural levels of perchlorate from vegetables irrigated with synthetic perchlorate 

containing water such as the Colorado River (or, as mentioned before, this non- relationship can be 

due to a lack of data points at those higher levels). Nevertheless those synthetic perchlorate levels 

are themselves still insignificant compared to the total goitrogen load. 

All this strengthens once more the argument that in the US population the potential iodine uptake 

inhibition does not lay with goitrogens and even less with perchlorate but clearly with a lack of 

iodine. 

Conclusion - Even though the goitrogen load of iodine insufficient women is only about half that of 

goitrogen sufficient women, their ratio iodine to goitrogen load is much lower which suggests once 

again that the remedy is iodine. - For low background levels of perchlorate there seems to exist a 

remarkable relationship with iodine which suggest that those lower levels are natural levels since 

synthetic perchlorate such as rocket fuel does not contain iodine. - It is once again suggested here 

that Iodine insufficient women seem to have also a diet low in vegetables besides a diet low in iodine 

containing food such as fish. 
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Response: EPA cannot evaluate calculations that have not been peer reviewed. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28878 

EPA Comment Code: 2600 

Comment: Fifth, the level of IUI that would be associated with exposure to perchlorate at the RfD 

is minimal compared to the IUI associated with other environmental goitrogens naturally present in 

many foods. Nitrate and thiocyanate are less potent (Tonacchera et al., 2004) but more plentiful 

inhibitors of NIS activity than perchlorate (Belzer et al., 2004). The potency of nitrate and 

thiocyanate relative to perchlorate has been demonstrated in vivo (Wyngaarden et al., 1952, 1953; 

Greer et al., 1966; Belzer et al., 2004) and in vitro (Tonacchera et al., 2004). When based on 

perchlorate equivalence, the effects of perchlorate are much smaller than the effects of either nitrate 

or thiocyanate (Belzer et al., 2004; U.S. EPA, 2008b). The potential for perchlorate to inhibit iodide 

uptake cannot be distinguished from the effects of other NIS inhibitors (De Groef et al., 2006). 

Because exposure to nitrate and thiocyanate would continue, the premise underlying EPA's attempt 

to isolate the effect of perchlorate is limited in its ability to provide an actual public health benefit. 

Response: See response to comment IDs 28529 and 28551 under comment code 2500. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28889 

EPA Comment Code: 2600 

Comment: One major scientific issue is that the effects of agents that affect IUI in the same way as 

perchlorate were not considered by the Notice. 

Because perchlorate, nitrate, and thiocyanate compete with iodine for uptake by the NIS, the 

combination of these chemicals in food or water will affect iodine uptake to the thyroid as well as 

absorption into the body from the gut. The NIS is located in the small intestine and uptake of iodine 

can be reduced by sufficient doses of perchlorate (Brown-Grant, 1961). In defining a HRL, it is 

assumed that 100% of an ingested dose is able to reach the thyroid. Of the four chemicals 

(perchlorate, nitrate, thiocyanate, iodine), perchlorate has the highest affinity for the NIS, however, 

the other three are more abundant in the diet. In the FDA Total Diet Study, the dose range of 

perchlorate was 2.4 to 9.1 ug/person-d and the dose range of iodine was 144 to 353 ug/person-d 

(Murray et al., 2008). Similar to biomonitoring studies (Blount et al., 2006) and dose models (Belzer 

et al., 2004), the OIG Draft Report (U.S. EPA, 2008b the results for exposures to nitrate, 

thiocyanate, and perchlorate found that perchlorate accounted for less than 1% of the predicted IUI 

in the total goitrogen load. Based on NHANES 2001-2002, the average urinary concentration of 

perchlorate was 4.8 ug/L, which was much lower than the urinary concentrations of nitrate, 

thiocyanate, and iodine at 55,017 ug/L, 2,042 ug/L, and 200 ug/L, respectively. Figure 2 

demonstrates the relative contribution of perchlorate to total goitrogen load using another set of 

data, the NHANES 2001-2002 database. 
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Figure 2. Total goitrogen load in perchlorate equivalence* based on urinary measurements from 

women ages 12 and older from NHANES 2001-2002.** [see PDF docket ID EPA-HQ-OW-2009-

0297-0662] 

One characteristic of this relationship is that as perchlorate dose increases in food, so does intake of 

nitrate, thiocyanate, and iodine. Figure 2 presents the cumulative intake of the four agents based on 

NHANES data using perchlorate equivalence of the urinary concentration of nitrate and 

thiocyanate. Two things become clear. First, as iodine level increases, so does total cumulative dose. 

Second, perchlorate contributes, by far, the smallest amount to total cumulative dose. The chart 

shows that as the goitrogen load increases, people tend to have increased intake of iodine, probably 

due to greater ingestion of total food. 

Response: See response to comment ID 28529 under comment code 2500. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group (EWG) 

EPA Document ID: EPA-HQ-OW-2009-0297-0499 

EPA Comment ID: 28928 

EPA Comment Code: 2600 

Comment: Background: Perchlorate is unique among chemical contaminants for its ubiquity- it has 

been found as a contaminant in drinking water in at least 26 states, in 74% of nearly 300 types of 

commonly consumed foods and beverages tested by the Food and Drug Administration (FDA), and 

in the urine of 100% of Americans tested by the Centers for Disease Control and Prevention (CDC) 

(GAO 2005, Blount et al 2006a, Murray et al 2008). Its primary clinical effects are on the thyroid 

gland, where it can disrupt the production of thyroid hormones that are critical for normal brain 

development and growth in the fetus, infants, and children. Perchlorate inhibits thyroid hormone 

synthesis by preventing iodine, the building block for thyroid hormones, from being taken up into 

the thyroid gland from the circulation. Iodine status is especially important in determining 

vulnerability to perchlorate, as confirmed by a recent large-scale epidemiological study from the 

CDC that found that women with lower iodine levels had more significant changes in thyroid 

hormone levels associated with environmental perchlorate exposure when compared with women 

with higher iodine levels (Blount et al 2006a). 

Response: EPA agrees that individuals with inadequate iodide nutritional status are more likely to 

be adversely impacted by perchlorate. 
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EPA Comment Code: 3000 Perchlorate Occurrence in Drinking Water 

Individual Comments 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0469 

EPA Comment ID: 19899 

EPA Comment Code: 3000 

Comment: Does the EPA's decision not to regulate perchlorate in drinking water mean that it 

accepts an exposure of 420 ppb in Utuado, Puerto Rico, or has that town's water supply been 

thoroughly inspected and all water sources with more than 15 ppb have been shut down? 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: AMWA 

EPA Document ID: EPA-HQ-OW-2008-0692-1525 

EPA Comment ID: 20446 

EPA Comment Code: 3000 

Comment: Other Considerations 

AMWA believes that factors other than those discussed in the notice need to be considered. The 

contamination of water supplies by perchlorate is on-going and spreading unlike many other CCL 

contaminants where a determination not to regulate has been made, such as in the case of pesticides 

that are no longer used and have low and decreasing occurrence levels. Perchlorate, on the other 

hand, is expected to have increasing occurrence levels and impact increasing numbers of water 

systems - clearly a call for at least the actions outlined herein. 

AMWA appreciates the opportunity to comment on EPA’s preliminary regulatory determination. If 

EPA has any question about our comments please do not hesitate to contact me or Erica Brown, 

Director of Regulatory Affairs, at 202-331-2820. 

Sincerely, 

Diane VanDe Hei Executive Director Cc: Cynthia Dougherty, OGWDW Eric Burneson, OGWDW 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. Regarding perchlorate contamination of water supplies, EPA acknowledges that some 

systems may have had an increase in perchlorate occurrence. The Agency analyzed the additional 

information and decided that regulation of perchlorate due to occurrence and health implications 

was warranted. 

Commenter Name: Mark S. Mayer 
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Commenter Organization: South Dakota Department of Environment & Natural Resources 

(DENR) 

EPA Document ID: EPA-HQ-OW-2009-0297-0467 

EPA Comment ID: 28483 

EPA Comment Code: 3000 

Comment: - Comments on interpreting occurrence data - Because South Dakota does not have any 

occurrence data, a new rule for Perchlorate would be another regulatory burden for our drinking 

water systems, but it would result in no positive health benefits for their customers. 

Response: Using the criteria mandated by the 1996 SDWA Amendments EPA has determined that 

regulation of perchlorate in drinking water systems presents a meaningful opportunity to reduce 

health risk for persons served by public water systems. See response to comment code 6120. 

Commenter Name: Andria Ventura 

Commenter Organization: Clean Water Action et al. 

EPA Document ID: EPA-HQ-OW-2009-0297-0528 

EPA Comment ID: 28512 

EPA Comment Code: 3000 

Comment: Perchlorate has been found in over 400 drinking water sources in 26 states, potentially 

affecting tens of millions of people. EPA's own data say that nearly 17 million people receive their 

water from public water systems where perchlorate has been found at levels exceeding 4 ppb. Were 

sampling routinely conducted with a detection limit of 1 ppb, that number would be much higherparticularly considering the estimated 20 million people in the Southwest who receive drinking water 

from the Colorado River. 

Response: EPA estimates that at least 5.1 to 16.6 million people are served by PWSs, for which we 

have data, that have perchlorate contamination. EPA has determined that a NPDWR for perchlorate 

could reduce perchlorate exposures for these populations to levels below the potential alternative 

HRLs that EPA has identified as levels of public health concerns for purposes of this determination, 

and that such exposure reductions present a meaningful opportunity for the reduction of health risks 

for persons served by PWSs. 

Commenter Name: Kathy Curtis 

Commenter Organization: Alliance of Nurses for Healthy Environments (ANHE) 

EPA Document ID: EPA-HQ-OW-2009-0297-0651 

EPA Comment ID: 28543 

EPA Comment Code: 3000 

Comment: Perchlorate has been found in more than 400 drinking water sources in 26 states, 

potentially affecting tens of millions of people. EPA's own data say that nearly 17 million people 

receive their water from public water systems where perchlorate has been found at levels exceeding 

4 ppb. 

Response: See response to comment ID 28512 under comment code 3000. 

Commenter Name: Tom Porta 
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Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 28747 

EPA Comment Code: 3000 

Comment: 4. The collection of new data for perchlorate in public water systems would provide 

reliable occurrence data to inform the establishment of a national primary drinking water standard. 

The need for new occurrence data is underscored by the significant improvements in water quality 

(considerably lower perchlorate concentrations) within the Lower Colorado River System since the 

UCMR 1 data were collected between 2001 and 2005. Additionally, newer and more sensitive 

analytical methods are now available that would permit perchlorate analysis with reporting limits 

(detection limits) at or below 1 ug/L. Consequently, the new occurrence data would represent a 

more robust data set that would permit statistical analysis without the inherent limitations present in 

the current Bayesian modeling of the existing, outdated occurrence data. 

Response: EPA acknowledges that there are newer and more sensitive analytical methods that are 

now available that would permit perchlorate analysis with reporting limits at or below 1 ug/L. The 

Agency does not believe that additional monitoring data is needed to determine that perchlorate 

meets SDWA’s criteria for regulating a contaminant. EPA's UCMR data is nationally representative 

and sufficient for estimating the frequency and level of perchlorate contamination. In addition, the 

Agency plans to further evaluate perchlorate occurrence as part of the proposed national primary 

drinking water regulation. 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 28754 

EPA Comment Code: 3000 

Comment: Comment C.4.a.2: The NDEP recommends EPA require collection of new occurrence 

data to support the latter two of the three criteria that EPA most demonstrate in order to regulate 

this contaminant in drinking water; namely: (1) the contaminant is known to occur (or there is a 

substantial likelihood that the contaminant will occur) in public water systems, with a frequency and 

at levels of public health concern; and (2) regulation of such a contaminant presents a meaningful 

opportunity for health risk reduction for persons served by public water systems. The existing 

occurrence data are both outdated and nonrepresentative of current conditions. 

The Unregulated Contaminant Monitoring Program is designed to collect such data for use in 

evaluating and prioritizing contaminants on the Drinking Water Contaminant Candidate List. It is an 

established program to "help ensure that future decisions on drinking water standards are based on 

sound science" (www.epa.gov/safewater/ucmr/ucmr1/factsheet.html#list). Perchlorate was on the 

analysis list published for the first Unregulated Contaminant Monitoring Rule (UCMR 1) in 1999 to 

collect data from 2,800 large public water systems and 800 small public water systems throughout 

the United States, but as further discussed elsewhere herein, the data is now largely obsolete due to 

analytical method changes and perchlorate remediation work in the Southwest. The NDEP 

recommends that EPA consider use of the established and successful UCMR process to collect 

updated national public water system occurrence data. 
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The NDEP believes use of outdated (historical) occurrence data collected from 2001 through 2005 

would be inappropriate because the quality of source water from the Lower Colorado River System 

has improved as a result of several successful remediation projects in the Las Vegas Valley. This 

source water provides the water supply for a large portion of the US population (approximately 26 

million US residents) and for a large amount of irrigated vegetable crops. The current perchlorate 

concentrations in the Lower Colorado River System are significantly lower than the concentrations 

present when the occurrence data were collected (2001 - 2005). The NDEP believes that collection 

of new occurrence data would permit a more accurate assessment of the exposure scenario and lead 

to a conclusion that regulation of perchlorate under the Safe Drinking Water Act (SDWA) does not 

present a meaningful opportunity for health risk reduction for persons served by public water 

systems or through ingestion of the referenced irrigated crops. The following summary of 

perchlorate remediation efforts within the Las Vegas Valley and corresponding water quality 

improvements within the Lower Colorado River system are provided to support this comment. 

Response: EPA disagrees with the statement that UCMR 1 data is obsolete. The UCMR 1 includes 

sample results reported by 3,865 public water systems between 2001 and 2005. This is the best 

available data collected in accordance with accepted methods on perchlorate. EPA recognizes that 

changes in perchlorate levels may have occurred in water systems since the UCMR samples were 

collected. However, EPA does not believe that the regulatory determination should be further 

delayed when we have a robust data set that can be used to evaluate occurrence. EPA plans to 

further analyze available perchlorate data in developing a proposed drinking water regulation. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 3100 UCMR 1 occurrence analysis 

Individual Comments 

Commenter Name: Ed Thomas 

Commenter Organization: National Rural Water Association (NRWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0163 

EPA Comment ID: 20271 

EPA Comment Code: 3100 

Comment: First, Phillips and Chambless,(see reference 1 electronic attachment - "Phillips 

compliance data variability.pdf") [see PDF of docket ID EPA-HQ- OW-2007-0068-0163] evaluated 

compliance data for several contaminants obtained from a cross section of state regulatory agencies 

and found consistently large variability in the means of quarterly samples taken for compliance 

purposes. This variability, expressed as the standard error of the mean divided by the mean, is 

significant enough (100% or more in many cases) to call into question the validity of decisions made 

based on these data. There is no reason to assume that the quality of the occurrence data from the 

UCMR effort would be any better than the quality of these compliance data, and NRWA strongly 

recommends that EPA resolve this quality issue before trying to make CCL2 regulatory decisions 

that are based on rather precise calculations of occurrence levels times the number of persons 

exposed. 

Response: EPA respectfully disagrees with NRWA on the assertion that the validity of occurrence 

data from UCMR be compromised based upon an analysis of variability in compliance monitoring 

data collected by public water systems. UCMR has gone under rigorous QA/QC measures to ensure 

that data variability is at a minimum. A detailed description of UCMR monitoring can be found in 

the Federal Register under docket number EPA–HQ–OW–2007–0068. The title of the reference 

that describes UCMR is “The Analysis Of Occurrence Data From The First Unregulated 

Contaminant Monitoring Regulation (UCMR 1) In Support Of Regulatory Determinations For The 

Second Drinking Water Contaminant Candidate List". 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1748 

EPA Comment ID: 20656 

EPA Comment Code: 3100 

Comment: Fifth, EPA has extensive monitoring data from public water systems on perchlorate 

occurrence in drinking water. While your November 5th letter [See PDF Docket ID EPA-HQ-OW2008-0692-1749] states perchlorate has "wide occurrence," EPA’s UCMR 1 data suggests that 

drinking water perchlorate occurrence is much less frequent that other compounds (sodium, 

manganese, sulfate, and boron) for which EPA has determined Federal drinking water standards are 

not necessary. The monitoring data also show that, for an overwhelming majority of the US 

population served by public water systems, exposure to perchlorate in drinking water is at a 

concentration much less than EPA’s calculated HRL of 15 ppb. In fact, based on UCMR1, only 

1.8% of public water systems had levels of perchlorate that were above the minimum reporting limit 

of 4 ppb.[FN8: US EPA, Unregulated Contaminant Monitoring Regulation 1 List 1 Assessment 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Monitoring, 1999.] Although unpublished, the EPA’s merger of the NHANES-UCMR1 datasets 

study has been peer-reviewed. 

Response: Administrator Stephen Johnson replied to the SAB on January 9, 2009. The letter is 

available in EPA’s docket ID No. EPA-HQ-OW-2009-0297 for this notice. EPA disagrees that only 

1.8% of public water systems had levels of perchlorate that were above the minimum reporting limit. 

In the October 2008 FR notice, EPA presented information on the drinking water occurrence of 

perchlorate. The data source was EPA's UCMR 1 and the samples were collected between 2001 and 

2005. A total of 34,331 samples were collected from 3,865 public water systems. EPA found that 

4.1% of the systems (160 out of 3,865 systems) reported perchlorate at, or above, the MRL of 

4ug/L. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-2082 

EPA Comment ID: 21027 

EPA Comment Code: 3100 

Comment: 10. Also regarding UCMR sampling, your letter questions the UCMR sampling because 

it focused only on large PWSs and does not account for exposure from "local hot spots" due to 

blasting, fireworks, and industrial and military releases. 

The UCMR is the most complete source of information on contaminant occurrence in the nation’s 

drinking water sources. The process for collecting data on unregulated contaminants in large as well 

as small water systems has been well established and relied upon by EPA for regulatory 

determinations from both the Contaminant Candidate List (CCL) 1 (issued July 2003) and CCL 2 

(issued July 2008). Additionally the National Rural Water Association, a non-profit federation of 

state rural water associations (and has the largest utility membership) expressed support for EPA’s 

preliminary determination, stating "the Agency has relied on sound science" in making its 

decision."[FN9: National Rural Water Association, Drinking Water Preliminary Regulatory 

Determination on Perchlorate (Docket Number: EPA-HQ-OW-2008-0692), Nov. 10, 2008.] 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Ellen Blaschinski, M.B.A., R.S. 

Commenter Organization: Regulatory Services Branch, Connecticut Department of Public Health 

EPA Document ID: EPA-HQ-OW-2008-0692-2091 

EPA Comment ID: 21116 

EPA Comment Code: 3100 

Comment: Public supplies in Connecticut were tested for perchlorate as part of the 2001 

Unregulated Contaminant Monitoring Rule (UCMR) round of testing. There were no detections in 

those systems at that time. However, that is a snapshot and not nearly the complete and ongoing 

surveillance that a federal MCL would provide. We note that the parallel UCMR testing in 

Massachusetts found very few detections of perchlorate and yet additional testing by the State of 

Massachusetts found substantial public water contamination on a site-related basis. Additional 

testing in Connecticut is warranted given the changing use pattern of perchlorate in blasting 

materials, fireworks and other applications. 
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Response: See response to comment ID 29097 under comment code 3100 and response to 

comment code 6120. 

Commenter Name: Kay Brothers 

Commenter Organization: Southern Nevada Water Authority 

EPA Document ID: EPA-HQ-OW-2009-0297-0667 

EPA Comment ID: 28700 

EPA Comment Code: 3100 

Comment: It is important for EPA to properly characterize its estimates of the potential population 

exposed to perchlorate. Perchlorate cleanup along the Colorado River has been very successful in 

recent years, and this represents the water supply for 26 million people in the Southwest. Perchlorate 

was detected in the Las Vegas Wash in 1997. The contamination was due to past disposal practices 

at the perchlorate manufacturing sites in the Las Vegas valley. Due to efforts of the manufacturers, 

Tronox LLC (Kerr-McGee Chemical LLC) and American Pacific Corporation, working with the 

Nevada Division of Environmental Protection, perchlorate concentrations entering Lake Mead and 

the lower Colorado River System have decreased dramatically. The perchlorate load entering Lake 

Mead in 1998 was 1013 lbs/day; it has been currently reduced to 61 lbs/day. 

Perchlorate concentrations have also decreased dramatically in the drinking water since 1998 

throughout the lower Colorado River system. The average perchlorate concentration reported by the 

Authority and the City of Henderson for the Unregulated Contaminate Monitoring Rule (UCMR) 

averaged 9.6ug/L and 2.9 ug/L, respectively. Currently, the perchlorate concentration in the 

Authority and the City of Henderson's drinking water is an average of 2.1ug/L. Drinking water 

providers along the lower Colorado River have reported similar decreases in perchlorate 

concentrations. The data collected for the UCMR may not reflect current perchlorate exposure for 

the Southwest. The average perchlorate concentration at Whitsett Reservoir for the last two years is 

1.6 ug/L. This is the Colorado River source water for the Metropolitan Water District of Southern 

California and the Central Arizona Project. California and Arizona blend with instate waters which 

result in a lower concentration. Three states have adopted perchlorate standards of 6 ug/L or less, 

which requires the water wells to be shut down if above the state limit. The exposure to perchlorate 

has been reduced significantly in the Southwest. 

If you have any questions about these comments, please do not hesitate to contact me at 702-862-

3708 or Shane Snyder at 702-856-3668. 

Sincerely, Kay Brothers Deputy General Manager Engineering and Operations 

KB/df Enclosure 

Reference: 

Amitai, Y., G. Winston, et al. (2007). "Gestational Exposure to High Perchlorate Concentrations in 

Drinking Water and Neonatal Thyroxine Levels." Thyroid 17(9): 843-850. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Baier-Anderson, C., B. Blount, et al. (2006). "Estimates of Exposures to Perchlorate from 

Consumption of Human Milk, Dairy Milk, and Water, and Comparison to Current Reference 

Dose." Journal of Toxicology and Environmental Health - Part A 69: 319-330. 

Blount, B. C., J. L. Pirkle, et al. (2006). "Urinary perchlorate and thyroid hormone levels in 

adolescent and adult men and women living in the United States." Environmental Health 

Perspectives Online. 

Blount, B. C., L. Valentin-Blasini, et al. (2006). "Perclorate exposure of the US population, 2001-

2002." Journal of Exposure Science and Environmental Epidemiology 1-9. 

Crump, K. S. and J. P. Gibbs (2005). "Benchmark calculations for perchlorate from three human 

cohorts " Environmental Health Perspectives 113: 1001-1008. 

Dasgupta, P. K., P. K. Martinelango, et al. (2005). "The origin of naturally occurring perchlorate: 

The role of atmospheric processes." environmental Science & Technology 39(6): 1569-1575. 

Dyke, J. V., K. Ito, et al. (2007). "Perchlorate in Dairy Milk. Comparison of Japan versus the United 

States." Environmental Science & Technology 41: 88-92. 

Greer, M. A., G. G. Goodman, et al. (2002). "Health Effects Assessment for Environmental 

Perchlorate Contamination: The Dose Response for Inhibition of Thyroidal Radioiodine Uptake in 

Humans." Environmental Health Perspectives 110(9): 927-937. 

Rajagopalan, S., T. A. Anderson, et al. (2006). "Widespread Presence of Naturally Occurring 

Perchlorate in High Plains of Texas and New Mexico." Environmental Science & Technology 40: 

3156-3162. 

Richardson, S. D. (2004). Environmental mass spectrometry: emerging contaminants and current 

issues. 76: 3337-3364. 

Rickman, J. E. (2003). "LC/MS/MS Measures Perchlorate in 0.1-0.3 ppb Range." Trends in 

Analytical Chemistry 22(10): viii-ix. 

Sanchez, C. A., R. I. Krieger, et al. (2005). "Potential perchlorate exposure from citrus irrigated with 

contaminated water." Analytica Chimica Acta peer- review. 

Snyder, S. A., R. C. Pleus, et al. (2006). "Perchlorate and chlorate in dietary supplements and flavor 

enhancing ingrediants." Analytica Chimica Acta 567: 23-32. 

Snyder, S. A., B. D. Stanford, et al. (2009). Hypochlorite - An Assessment of Factors That Influence 

the Formation of Perchlorate and Other Contaminants., American Water Works Association. 140 

pages. 

Snyder, S. A., B. J. Vanderford, et al. (2005). "Trace analysis of bromate, chlorate, iodate, and 

perchlorate in natural and bottled waters." Environmental Science & Technology 39(12): 4586-4593. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Tellez, R. T., P. M. Chacon, et al. (2005). "Long-term environmental exposure to perchlorate 

through drinking water and thyroid function during pregnancy and the neonatal period." Thyroid 15: 

963-975. 

Valentin-Blasini, L., J. P. Mauldin, et al. (2005). "Analysis of perchlorate in human urine using ion 

chromatography and electrospray tandem mass spectrometry." Analytical Chemistry 77(8): 2475-

2481. 

Response: EPA is aware of perchlorate cleanup along the Colorado River and believes that it has 

properly characterized the estimate of population exposed to perchlorate in drinking water. See 

response to comment ID 28856 under comment code 3100. 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 28756 

EPA Comment Code: 3100 

Comment: Consequently, the NDEP believes use of outdated (historical) occurrence data collected 

from 2001 through 2005 would be inappropriate because the source water (Lower Colorado River 

System) for a large portion of the US population and for a large amount of irrigated vegetable crops 

has substantially improved as a result of several successful remediation projects in the Las Vegas 

Valley. The current perchlorate concentrations are significantly lower than the historical 

concentrations when the occurrence data were collected (2001 - 2005). Moreover, current 

concentrations of perchlorate in the Lower Colorado River System are less than health-protective 

levels for the approximately 26 million US residents who use this water for drinking water and 

numerous agricultural operations for irrigating crops. The NDEP believes that collection of new 

occurrence data would provide for a more accurate assessment of the exposure scenario applicable 

to this large segment of the US population, and lead to a conclusion that regulation of perchlorate 

under the SDWA does not present a meaningful opportunity for health risk reduction for persons 

served by public water systems or consuming the above-referenced irrigated crops. 

References 

Amitai, Y, Winston, G, Sack, J, et al. 2007. Gestational exposure to high perchlorate concentrations 

in drinking water and neonatal thyroxine levels. Thyroid. 17(9): 843-850. 

Andersen, S, Pedersen, KM, Pedersen, IB, et al. 2001. Variations in urinary iodine excretion and 

thyroid function. A 1-year study in healthy men. Eur. J. Endocrinol. 144: 461-465. 

Brabant, G, Bergmann, P, Kirsch, CM, et al. 1992. Early adaptation of thyrotropin and thyroglobulin 

secretion to experimentally decreased iodine supply in man. Metabolism 41(10): 1093-1096. 

Braverman, LE, Pearce, EN, He, X, et al. 2006. Effects of six months of daily low-dose perchlorate 

exposure on thyroid function in healthy volunteers. J. Clin. Endocrinol. Metab. 91(7): 2721-2724. 

Braverman, LE. 2009. Environmental perchlorate: perhaps much ado about nothing. Endocr. Pract. 

15(1): 50-52. 
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Braverman, LE, He, X, Pino, S, et al. 2005. The effect of perchlorate, thiocyanate, and nitrate on 

thyroid function in workers exposed to perchlorate long-term. J. Clin. Endocrinol. Metab. 90(2): 

700-706. 

Burner, PA, Kelsh, MA, Lau, EC, et al. 2006. Thyroid function and perchlorate in drinking water: an 

evaluation among California newborns, 1998. Environ. Health Perspect. 114(5): 798- 804. 

Chang, S, Crothers, C, Lai, S, et al. 2003. Pediatric neurobehavioral diseases in Nevada counties with 

respect to perchlorate in drinking water: an ecological inquiry. Birth Defects Res. A. Clin. Mol. 

Teratol. 67: 886-892. 

Crump, C, Michaud, P, Tellez, R, et al. 2000. Does perchlorate in drinking water affect thyroid 

function in newborns or school-age children? J. Occup. Environ. Med. 42(6): 603-612. 

Dohan, O, Portulano, C, Basquin, C, et al. 2007. The Na+/I- symporter (NIS) mediates 

electroneutral active transport of the environmental pollutant perchlorate. Proc. Natl. Acad. Sci. 

104(51): 20250-20255. 

Eng, PH, Cardona, GR, Fang, SL et al. 1999. Escape from the same Woff-Chiaikoff effect is 

associated with the decrease in thyroid sodium/iodide symporter messenger ribonucleic acid and 

protein. Endocrinol 40:3404-3410. 

Gibbs, JP, Narayanan, L, and Mattie, DR. 2004. Crump et al. study among school children in Chile: 

subsequent urine and serum perchlorate levels are consistent with perchlorate in water in Taltal. J. 

Occup. Environ. Med. 46: 516-517. 

Gibbs, JP, Ahmad, R, Crump, KS, et al. 1998. Evaluation of a population with occupational 

exposure to airborne ammonium perchlorate for possible acute or chronic effects on thyroid 

function. J. Occup. Environ. Med. 40(12): 1072-1082. 

Gibbs, JP, and Van Landingham, C. 2008. Urinary perchlorate excretion does not predict thyroid 

function among pregnant women. Thyroid. 18(7): 807-808. 

Glinoer, D. 1997. The regulation of thyroid functioning pregnancy: Pathways of endocrine 

adaptation from physiology to pathology. Endocr. Rev 18:404-433. 

Greer, MA, Goodman, G, Pleus, RC, et al. 2002. Health effects assessment for environmental 

perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake in 

humans. Environ. Health Perspect. 110(9): 927-937. 

Johnston, S, Branch, RB, Brent, G, et al. 2005. Health implications of perchlorate ingestion. 

National Academy Press. Washington DC. 

Kelsh, MA, Buffler, PA, Daaboul, JJ, et al. 2003. Primary congenital hypothyroidism, newborn 

thyroid function, and environmental perchlorate exposure among residents of a southern California 

community. J. Occup. Environ. Med. 45(10): 1116-1127. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Kirk, AB, Martinelango, PK, Tian, K, et al. 2005. Perchlorate and iodide in dairy and breast milk. 

Environ. Sci. Technol. 39(7): 2011-2017. 

Kogai, T, Endo, T, Saito, T, et al. 1997. Regulation by thyroid-stimulating hormone of 

sodium/iodide symporter gene expression and protein levels in FRTL-5 cells. Endocrinol 138:2227-

2332. 

Lamm, SH, Braverman, LE, Li, FX, et al. 1999. Thyroid health status of ammonium perchlorate 

workers: a cross-sectional occupational health study. J. Occup. Environ. Med. 41(4): 248-260. 

Lawrence, JE, Lamm, SH, Pino, S, et al. 2000. The effect of short-term low-dose perchlorate on 

various aspects of thyroid function. Thyroid. 10(8): 659-663. 

Leung, AM, Pearce, EN, Hamilton, T, et al. 2009. Colostrum iodine and perchlorate concentrations 

in Boston-area women: a cross-sectional study. Clin. Endocrinol. 70: 326-330. 

Li, FX, Byrd, D, Deyhle, GM, et al. 2000a. Neonatal thyroid-stimulating hormone level and 

perchlorate in drinking water. Teratology 62: 429-431 

Li, FX, Squartsoff, L, and Lamm SH. 2001. Prevalence of thyroid diseases in Nevada counties with 

respect to perchlorate in drinking water. J. Occup. Environ. Med. 43(7): 630-634. 

Li, Z, Li, FX, Byrd, D, et al. 2000b. Neonatal thyroxine level and perchlorate in drinking water. J. 

Occup. Environ. Med. 42(2): 200-205. 

McGinley & Associates. 2003. Las Vegas Wash Initial Perchlorate Modeling Report, Las Vegas 

Wash, Henderson, Nevada. 

McLanahan, ED, Andersen, ME, Campbell, JL Jr., et al. 2009. Competitive inhibition of thyroidal 

uptake of dietary iodide by perchlorate does not describe perturbations in rat serum total T4 and 

TSH. Environ. Health Perspect. 117(5): 731-738. 

Metropolitan Water District (MWD) of Southern California. 2009. Whitsett Data (Graph and Data) 

Perchlorate Concentration - Whitsett Sampling Point - MWD Data 

Moore, WW. 1984. Thyroid Physiology, In: Physiology, 5th Edition, Selkurt, EE (ed.), Little, Brown 

and Company, Boston, pp. 618-627. 

Moulopoulos, DS, Koutras, DA, Mantzos, J, et al. 1988. The relation of serum T4 and TSH with the 

urinary iodine excretion. J. Endocrinol. Invest. 11: 437-439. 

Nevada Division of Environmental Protection (NDEP). 2009a. Breakthrough Curve (Graph and 

Data); Breakthrough curve: 90% efficient model results, mass 

NDEP). 2009b. Northshore Road Data (Graphs and Data) Perchlorate loading - Las Vegas Wash - 

Northshore Road sampling point, real-time flow values (December 1997 to July 2009) Perchlorate 

loading (12-month rolling average) - Las Vegas Wash - Northshore Road sampling point, real-time 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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flow values (December 1997 to July 2009) Perchlorate concentration - Las Vegas Wash - 

Northshore Road sampling point (January 1998 through January 2009) 

NDEP). 2009c. Power Point Presentation: Perchlorate Remediation in the Las Vegas Valley and the 

Colorado River Impacts. September. 

NDEP). 2009d. Water Quality vs. Remediation (Figures) Remediation Time-lines for AMPAC and 

Tronox Breakthrough Curve: 90% Efficient Model Results Map of Perchlorate Concentration 

Ranges for the Lower Colorado River System Perchlorate Loading - Las Vegas Wash - Northshore 

Road Sampling Point, Real-Time Flow Values Willow Beach sampling point Perchlorate 

concentration - Colorado River - Whitsett Intake Sampling Point 

NDEP). 2009e. Willow Beach Data (Graph and Data) Perchlorate concentration & specific 

conductance, Colorado River - Willow Beach AZ sampling point 

NRC. 2005. Health implications of perchlorate ingestion. Panel members Johnston, S, Jr, Branch, 

RB, Brent, G, et al. , National Research Council Committee to Assess Health Implication of 

Perchlorate Ingestion, National Academy Press, Washington, DC. 

Okabe, N, Hokaze, M. 1993. Effects of inorganic anions on the binding of thyroxine by bovine 

serum albumin. Chem Pharm Bull 41:430-432. 

Paulus, BF, Bazar, MA, Salice, CJ, et al. 2007. Perchlorate inhibition of iodide uptake in normal and 

iodine-deficient rats. J. Toxicol. Environ. Health A. 70: 1142-1149. 

Pearce, EN, Lazarus, JH, Smythe, PP, et al. 2007a. Thyroid function is not affected by 

environmental perchlorate exposure in first trimester pregnant women. Thyroid Suppl. 17: S 133-S 

134. 

Pearce, EN, Leung, AM, Blount, BC, et al. 2007b. Breast milk iodine and perchlorate concentrations 

in lactating Boston-area women. J Clin Endocrinol Metab 92:1673-1677/ 

Siglin, JC, Mattie, DR, Dodd, DE, et al. 2000. A 90-day drinking water toxicity study in rats of the 

environmental contaminant ammonium perchlorate. Toxicol. Sci. 57: 61-74. 

Southern Nevada Water Authority (SNWA). 2009a. Lake Mead Monthly Stream Report (Graphs 

and Data) SNWS. Raw and finished perchlorate (March 5, 1999 to July 20, 2009) AMSWTF. 

Finished water perchlorate concentrations - 1997 to 2002 Saddle Island intake at 1050 feet raw water 

perchlorate concentrations SNWS raw and finished perchlorate concentrations (October 24, 2002 to 

June 29, 2009) Alfred Merritt Smith WTF and River Mountains WTF finished water (October 24, 

2002 to November 24, 2008) 

SNWA) 2009b. Lake Mead Monthly Average. Graphs and Data Perchlorate yearly average, 

AMSWTF raw water (2000 to 2009) 

Tellez, R, Chacon, P, Abarca, C, et al. 2007. Gestational exposure to high perchlorate concentrations 

in drinking water and neonatal thyroxine levels. Thyroid 17:843-850. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Tellez, RT, Chacon, PM, Abarca, CR, et al. 2005. Long-term environmental exposure to perchlorate 

through drinking water and thyroid function during pregnancy and the neonatal period. Thyroid 

15:963-975 

Tran, N, Blasini-Valentin, L, Blount BC, et al. 2008. Thyroid-stimulating hormone increases active 

transport of perchlorate into thyroid cells. Am. J. Physiol. Endocrinol. Metab. 294: 802-806. 

United States Environmental Protection Agency, December 2008. Interim Drinking Water Health 

Advisory for Perchlorate. Health and Ecological Criteria Division, Office of Science and 

Technology, Office of Water, U.S. Environmental Protection Agency, Washington, DC 20460. EPA 

822-R-08-025. 

Yamada, T. 1967. Effects of perchlorate and other anions on thyroxine regulation of thyroid 

function. J Biol Chem 174:555-564. 

Yu, KO, Narayanan, L, Mattie, DR, et al. 2002. The pharmacokinetics of perchlorate and its effect 

on the hypothalamus-pituitary-thyroid axis in the male rat. Toxicol. Appl. Pharmacol. 182: 148-159. 

Response: See response to comment ID 28856 under comment code 3100 and ID 28754 under 

comment code 3000. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28839 

EPA Comment Code: 3100 

Comment: With respect to using UCMR data to estimate concentrations above 4 ug/L, again 

AMWA urges EPA to recognize that occurrence in finished water at many water systems has 

decreased. 

Response: See response to comment ID 28856 under comment code 3100. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0415 

EPA Comment ID: 28856 

EPA Comment Code: 3100 

Comment: Current National Exposure to Drinking Water Perchlorate 

AWWA believes that the population exposed to perchlorate that was indicated by EPA's UCMR1 

data is no longer valid. In an informal survey conducted by AWWA, we found that many sources 

that had detected perchlorate from UCMR1 monitoring are either no longer being used or are being 

treated per the requirements of maximum contaminant levels (MCL's) established in California and 

Massachusetts. Additionally, successful treatment of the perchlorate source to Colorado River 

contamination has lowered concentrations to below 4 ug/L. AWWA believes that EPA would be 

well served to work with state primacy agencies to evaluate the 160 water systems with perchlorate 
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detections from UCMR1 to determine the actual national population currently exposed to 

perchlorate above 4 ug/L. AWWA believes this information will further help inform EPA as to 

whether there is a meaningful opportunity for health risk reduction by regulating perchlorate. 

Response: EPA acknowledges that there may be changes (increasing or decreasing) in the levels of 

perchlorate in public water systems since the UCMR data were collected from 2001 to 2005. EPA 

believes the UCMR data are best available data collected in accordance with accepted methods on 

the frequency and level of occurrence in drinking water. Therefore EPA is basing its occurrence 

evaluation on these collected data for the regulatory determination and will further evaluate 

perchlorate occurrence as part of the proposed rulemaking. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28870 

EPA Comment Code: 3100 

Comment: 3. Use of data on perchlorate occurrence in drinking water: The occurrence analysis 

presented in the Notice relies on data that are nearly a decade old and it assumes exposure to 

maximum concentrations detected anywhere within a public water system (PWS), even in untreated 

source water. Therefore, the analysis most likely overestimates concentrations of perchlorate in 

drinking water. Additionally, the Notice's estimates of populations exposed to perchlorate are 

overstated because it assumes the entire population served by a PWS is exposed to the maximum 

concentration, even if the detection was in untreated source water, and it overlooks the steps that 

have been taken- particularly in California, Massachusetts and New Jersey-that substantially reduce 

the national population that may be exposed to environmental levels of perchlorate. The process the 

Notice followed to develop the estimated populations is not transparent, and as a result, it is not 

possible to independently calculate the estimated values in the Notice based on the information 

given. Independent calculations resulted in estimated population sizes that are about half of the 

Notice's estimates, even when conservative assumptions were used. EPA should use more current 

data to estimate occurrence as levels in drinking water have decreased since UCMR1 monitoring. 

Response: See response to comment ID 28856 under comment code 3100 in regards to changes in 

the levels of perchlorate occurrence. With respect to EPA’s evaluation of populations exposed to 

perchlorate, the Agency has presented analyses as part of its October 2008 Federal Register Notice, 

August 2009 Federal Register Notice, and the Final Federal Register Notice that explains EPA’s 

estimation of populations potentially exposed to perchlorate. Using the UCMR 1 data, EPA took 

into account the potential for overestimating populations exposed to perchlorate using UCMR 1 

monitoring data in which one can assume that the entire population served by a PWS is exposed to 

the maximum concentration from a single detection. Therefore, to respond to this concern, EPA 

also developed a central value estimate by assuming the population was equally distributed among all 

entry points and added only the proportion of the total population served by those entry points in a 

PWS that had at least one sample with perchlorate concentrations greater than the HRL being 

evaluated. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 
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EPA Comment ID: 28890 

EPA Comment Code: 3100 

Comment: C. Use of Data on Perchlorate Occurrence in Drinking Water 

To estimate how many people potentially could be exposed to perchlorate in drinking water, EPA 

used data from its first cycle of the UCMR1 

(http://www.epa.gov/safewater/ucmr/ucmr1/index.html). The Notice presents the resulting 

population estimates in Table 3. The Agency estimated the size of the population exposed to 

perchlorate at different threshold levels (4 ug/L or higher, 5 ug/L or higher, etc.) by assuming that 

the entire population served by a public water system (PWS) is exposed to perchlorate at 

concentrations above a threshold level if at least one sample collected in the PWS contained 

perchlorate at or above the threshold level (even if all other samples are lower, or nondetect). Based 

on this assumption, the Notice reports an estimate of 16.6 million (M) people exposed to 

perchlorate at concentrations above the method reporting limit (MRL) of 4 ug/L. In addition, the 

Agency developed an alternative assessment by assuming that populations served by PWSs are 

equally distributed among entry points to the PWS and that only those portions of the population 

served by entry points with reported concentrations above the threshold are exposed. Based on this 

assumption, the Notice reports an estimate of 5.1M people exposed to perchlorate at concentrations 

above the MRL of 4 ug/L. 

The Notice asks for comment on three general questions regarding the use of occurrence data to 

estimate exposure to perchlorate. Responses to these questions, based on the best available scientific 

information, follow. 

Response: No response necessary to this summary of EPA information. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28892 

EPA Comment Code: 3100 

Comment: Scientific and statistical concerns with the Notice's use of the UCMR1 data set include 

the following: 

* UCMR1 covers the years 2001 to 2005; some of these data are nearly a decade old. Data collected 

during this time overestimate current concentrations of perchlorate in drinking water. Guidelines 

EPA has established since 1992, including interim guidance for remediation and water exposure 

levels, and remediation of contaminated sites by responsible parties, have resulted in reductions in 

perchlorate levels in ground and surface water. For example, public information shows that annual 

average concentrations of perchlorate at the Las Vegas drinking water intake in Lake Mead declined 

almost 60% between 2000 and 2004 (from 13.1 ppb to 5.6 ppb), and the annual average 

concentrations in the Metropolitan Water District Colorado River Aqueduct intake at Lake Havasu 

on the Lower Colorado River declined about 50% between 2000 and 2004 (from 6.4 ppb to less 

than 4 ppb), and in 2004 nine of the twelve monthly samples were at levels too low to detect (i.e., 

below 4 ppb) (http://www.epa.gov/region/toxic/perchlorate/per_nv.html). The Colorado River 
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supplies water for agriculture in Arizona and California as well as drinking water for Southern 

California. 

* Environmental exposure levels of perchlorate are declining. Although not an occurrence study, a 

recent study reports that urinary concentration of perchlorate is lower in NHANES 2003-2004 

participants compared to NHANES 2001-2002[FN15: NHANES 2001-2002 is the basis for the 

study by Blount et al. (2006). See following section for the full discussion on Blount et al. (2006).] 

suggesting population exposure was lower during 2003-2004 (Mendez et al., 2009). 

* Examination of the UCMR1 data set demonstrates that several major U.S. cities did not detect 

perchlorate in their drinking water. These cities are large metropolitan areas with corresponding 

large populations and include Washington DC, New York City, Newark, Baltimore, Philadelphia, 

Pittsburgh, Minneapolis/ St. Paul, Chicago, Milwaukee, Detroit, Cleveland, Indianapolis, Memphis, 

Nashville, Atlanta, St. Louis, San Francisco, Seattle, and Portland. Perchlorate is not ubiquitous in 

drinking water, but areas of detection appear to be regionalized. This does not diminish the 

importance of perchlorate where it has been detected at levels above the MRL (4 ug/L). States 

where significant perchlorate is present, e.g., California, have either promulgated drinking water 

standards or adopted EPA interim guidance. As a result, the trend of occurrence is toward lower 

water concentrations. 

* The population estimates presented in Table 3 of the Notice could not be validated. The Notice 

does not present all of the assumptions used to calculate population sizes. When extremely 

conservative assumptions are made, calculated population sizes are still much lower than EPA's 

estimates. For example, if it is assumed that the entire population served by a PWS is exposed to 

perchlorate at levels above the MRL when at least one sample collected in the PWS contained 

perchlorate at or above the MRL (even if all other samples did not detect perchlorate) and that the 

size of the population is the maximum associated with the category assigned to a given PWS (i.e., 

very small, small, medium, large, very large), the computed maximum exposed population size is 

approximately 10.5M-this is approximately 60% of EPA's maximum estimate of 16.6M. This lower 

estimate is still extremely conservative and unlikely to accurately represent the size of the exposed 

population. The entire population served by the PWS is not likely to be served water from the entry 

point that had the highest reported concentration, and actual population sizes for each PWS are 

likely to be distributed across the range of population sizes associated with a given population 

category. Alternatively, if it is assumed that the population served by a PWS is equally distributed 

among entry points to the PWS and the total exposed population is computed based only on those 

entry points where perchlorate was detected above the MRL (i.e., in a manner consistent with the 

last column of EPA's Table 3), the estimated population size is about half of EPA's 5.1M estimate. 

* It appears that EPA included monitoring data for untreated source water in its exposure estimates. 

Based on the data retrieved from EPA's UCMR1 website, the UCMR1 data includes a total of 

34,728 analyses for perchlorate (EPA reports 34,221 analyses), with 647 detections of perchlorate at 

or above the MRL (EPA reports 637 detects). These detections include 288 detections in source 

water (out of 10,684 samples, or a frequency of detection of 2.7%) and 348 detections in entry point 

water (out of 23,319 samples, or 1.5%) (perchlorate was not detected in any samples from the 

midpoint of distribution systems (n = 16), the point of maximum retention (n = 19), or the location 

in distribution systems where disinfectant residual is lowest (n = 6); perchlorate was detected in 11 

of 684 samples from "unknown" locations). Thus, it is questionable as to whether the number of 
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people presented in the Notice is likely to drink untreated source water from PWSs, and data from 

drinking water entry points indicates that concentrations at the entry points are generally lower. 

These observations indicate that using the UCMR1 database to extrapolate exposures to 

concentrations below the MRL would be inappropriate, as it would produce highly inaccurate 

estimates. 

Response: Regarding the comment that UCMR data overestimates current concentrations of 

perchlorate in drinking water, see response to comment ID 28856 under comment code 3100. 

Regarding the comment that perchlorate is not ubiquitous in drinking water but areas of detection 

appear to be regionalized, UCMR data is the most extensive nationally representative occurrence 

data for perchlorate in public water systems; therefore, EPA analyzed this data and additional 

occurrence data in making a regulatory determination for perchlorate as required by Congress. See 

SDWA Section 1445(g). 

Regarding validation of population estimates, see responses to comment IDs 28856 and 28870 

under comment code 3100. Also, see "The Analysis Of Occurrence Data from The First 

Unregulated Contaminant Monitoring Regulation (UCMR 1) In Support Of Regulatory 

Determinations For The Second Drinking Water Contaminant Candidate List" for a description of 

how the UCMR 1 population analysis was conducted. 

EPA disagrees with the commenter that approximately half of perchlorate water samples in the 

UCMR 1 database are from untreated source waters. The data EPA used to evaluate perchlorate 

occurrence from UCMR 1 was only taken from finished water. EPA did allow monitoring at source 

water sampling points; however, if perchlorate was detected in a source water sample, the UCMR 1 

required that follow-up samples be collected at the entry point to the distribution system and follow 

the monitoring frequency specified in the rule for the contaminant and water source type. A detailed 

description of UCMR monitoring can be found in the Federal Register under docket number EPA–

HQ–OW–2007–0068. The title of the reference that describes UCMR is "The Analysis Of 

Occurrence Data From The First Unregulated Contaminant Monitoring Regulation (UCMR 1) In 

Support Of Regulatory Determinations For The Second Drinking Water Contaminant Candidate 

List." 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28904 

EPA Comment Code: 3100 

Comment: 3. EPA's proposed analysis of occurrence data is concerning in that the estimated 

population sizes in the Notice could not be reproduced, the data from UCMR1 are not current and 

likely overestimate current exposures, and the highest concentration detected anywhere in a PWS 

was used to estimate exposures for all people served by the PWS, even if the sample was collected 

from untreated source water or all other samples were nondetects. Altogether, these assumptions 
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produce an inaccurate and overly conservative estimate of potential human perchlorate exposures 

from drinking water. 

Response: See response to comment IDs 28856 and 28870 under comment code 3100. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 29097 

EPA Comment Code: 3100 

Comment: EPA assumes that if the drinking water testing at the entry point reports at least one 

sample above the detection limit during the 2000-2005 UCMR sampling period, the entire 

population that draws drinking water from that intake is exposed. EPA then multiplies this estimate 

of the exposed population by an estimate of the proportion of the national population that is 

pregnant during any given year. 

The major overestimate in EPA's calculation concerns the population exposed above the HRL. 

Under the UCMR regulation, public water systems were required to take multiple samples 

throughout the year at each sampling point. Large public water systems were required to monitor 

throughout a three-year period. Many of the sampling points only reported a single detection during 

the sampling period. Few systems reported perchlorate detections in every sample. Therefore, 

assuming the total population is exposed at any given time is a gross overestimate. A more likely 

estimate is the ratio of positive defects to total samples multiplied by the service population. 

There are many reasons why a system may have intermittent or a single detection. At the beginning 

of the UCMR sampling period, laboratory experience with detecting perchlorate was evolving. There 

have been many anecdotal reports of false detections. Even where perchlorate was found in the 

drinking water, its occurrence may have been intermittent. Since perchlorate can be naturally formed 

and then fall to the earth in precipitation, it is likely that watershed concentrations ebb and flow with 

the natural water cycle. 

EPA's estimate in the proposed determination also overestimates the likely number of individuals 

with drinking water concentrations above the HRL for several other reasons. First, EPA failed to 

remove individuals who primarily consume bottled water or have in-house treatment systems. EPA 

did exclude these individuals in its analysis of the UCMR/NHANES data sets. 

Second, EPA did not account for system changes in response to the UCMR monitoring. Some 

states have enacted state-specific drinking water standards. Others have issued advisory levels. Public 

water systems have responded and have made changes to reduce perchlorate concentrations. These 

changes are exactly the responses the Safe Drinking Water Act encourages. By prompting local 

actions, drinking water issues are separated into the local and national concerns. EPA should 

properly account for these local actions in its population estimate so as to reinforce its finding that 

exposure does not occur with sufficient frequency to warrant national regulation. 

More importantly, EPA should provide the public context for this exposure estimate. Even though 

there may be potentially exposed individuals above the HRL, the overwhelming scientific evidence 
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from clinical studies, environmental studies, and from PBPK modeling demonstrates that no one 

faces an appreciable risk of adverse effect from exposures at EPA's reference dose. 

Response: EPA has used the best available data on the frequency and level of perchlorate 

occurrence in drinking water, the population exposed to perchlorate, and the levels of public health 

concern to determine that there is a meaningful opportunity for health risk reduction through a 

national primary drinking water regulation. EPA believes that this analysis is appropriate for making 

the determination to regulate perchlorate which will initiate a more rigorous health risk reduction, 

cost analysis, and other analyses required by the Safe Drinking Water Act for proposed drinking 

water standards. EPA believes that it is appropriate to consider the single highest value reported in a 

public water system and the highest level within a entry point into the system. While EPA does 

acknowledge that perchlorate concentrations may fluctuate over time, the duration of life stages 

where individuals are most sensitive to the effects of perchlorate exposure (i.e., pregnancy and 

infancy) are relatively short. Therefore EPA believes it is appropriate to use the single highest result 

from a quarterly or semi-annual sample to determine if these populations are exposed at levels of 

health concern. 

EPA does not believe that multiplying the ratio of positive detects to total samples by the service 

population is appropriate because this approach would not account for the fact that during certain 

periods of time the whole population was potentially exposed to perchlorate in drinking water at 

levels of health concern. EPA does not believe that is appropriate to remove persons who use in 

house treatment or consume bottled water for these estimates of population potentially exposed. 

The bottled water consumption and in house treatment data were available for NHANES 

participants but are not collected or reported under the UCMR. EPA believes that a more rigorous 

evaluation of the variation in drinking water consumption can be made as part of the health risk 

reduction and cost analyses required under SDWA for proposed national primary drinking water 

regulations. 

EPA does not believe that it is appropriate to adjust estimates of perchlorate occurrence from those 

measured under UCMR. EPA believes that the UCMR is the best available data on the frequency 

and level of perchlorate occurrence in public water systems nationally. EPA acknowledges that levels 

of perchlorate may have decreased in some public water systems as a result of state regulation or of 

water system decisions. However, those may also be instances in which levels of perchlorate may 

have increased due to new contamination. EPA further notes that public water systems would 

conduct monitoring under the national primary drinking water regulation we expect to promulgate. 

Systems which do not detect perchlorate at levels exceeding the MCL will not be required to take 

action to lower perchlorae levels. Therefore if systems have already taken actions to address 

perchlorate in their drinking water, these systems may not have to take any further steps to remove 

perchlorate . 

Regarding the statement that no one faces an appreciable risk of adverse effects from exposures at 

EPA’s reference dose, a recent study (Steinmaus et al., 2010) examining the perchlorate 

concentration in drinking water and its association with neonatal thyroid hormone levels in over 

400,000 newborns, concluded that there is a statistically significant association with perchlorate 

exposure and increased neonatal thyroid hormone levels. This study has shown that, at 

environmental concentrations of perchlorate greater than 5 ug/L, the odds of elevation in thyroid 

stimulating hormone (TSH) levels at birth was significantly greater, when compared to hormone 

levels in newborns from communities unexposed to perchlorate. Steinmaus et al. (2010) grouped 
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geographic communities in California according to whether their respective estimated average 

perchlorate concentrations were either more or less than 5 ug/L, therefore, unexposed communities 

in this particular study were defined as having less than 5 ug/L drinking water perchlorate 

concentrations (representing an average estimate of perchlorate concentrations of the different water 

systems supplying a given community, and weighted by the number of water sources used by each 

system). Therefore, for the Steinmaus et al. (2010) study, this particular unexposed group includes 

communities with estimated average perchlorate concentrations of 5 μg/L or less, as well as all 

communities with no measurable environmental perchlorate concentrations. The U.S. EPA 

reference dose for perchlorate is 0.7 ug/kg/day. EPA has adopted the NRC’s recommendations 

regarding the reference dose for perchlorate in its “Integrated Risk Information System” (IRIS) 

(USEPA 2005), resulting in an RfD of 0.7 ug/kg/day, which was derived by applying a 10-fold (10x) 

uncertainty factor to the NOEL of 7.0 ug/kg/day. 
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EPA Comment Code: 3120 UCMR 1 statistical methodology and nationally 

representative sample of small systems 

Individual Comments 

Commenter Name: Melanie A. Marty, Ph.D. 

Commenter Organization: Children's Health Protection Advisory Committee 

EPA Document ID: EPA-HQ-OW-2008-0692-0962 

EPA Comment ID: 20420 

EPA Comment Code: 3120 

Comment: The other concern is that, as noted earlier, without a federal MCL, detections of high 

level contamination (e.g., 1300 ug/L of perchlorate in a public water supply in Boxborough MA) will 

go undetected leading to high localized exposures. This high level of contamination would not have 

been detected without a state initiated testing program (MADEP, 2005). Given the unpredictable 

nature of these extreme concentrations, national monitoring is clearly needed. 

The 2001 Unregulated Contaminant Monitoring Regulation (UCMR) for perchlorate focused upon 

larger public water supplies and is not indicative of the numbers of people exposed or extent of 

exceedances possible from localized hot spots due to contamination of water from blasting, 

fireworks or industrial/military releases. 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. EPA intends to consider compliance monitoring requirements and request comment as 

part of the expected proposed national primary drinking water regulation for perchlorate. EPA 

disagrees with the statement that the UCMR is not indicative of the numbers of people exposed to 

perchlorate. Under UCMR 1, EPA collected samples from all the large PWS (3,865) and 800 small 

PWS which were a stratified random sample of public water systesms selected to represent drinking 

water occurrence nationally. EPA has determined that UCMR 1 is the best available scientific 

perchlorate occurrence data collected in accordance with acceptable analytical methods. EPA’s 

determination is based upon the fact that UCMR1 is the most nationally representative study of the 

frequency and levels of perchlorate in drinking water systems. 

Commenter Name: Ron Curry 

Commenter Organization: New Mexico Environment Department 

EPA Document ID: EPA-HQ-OW-2008-0692-1796 

EPA Comment ID: 20932 

EPA Comment Code: 3120 

Comment: Because perchlorate is not currently regulated under the SDWA, data on perchlorate 

contamination in New Mexico public water systems is limited. Under the Unregulated Contaminant 

Monitoring Rule,[FN1: 40 C.F.R. [section] 141.40.] public water systems serving communities of 

greater than 10,000 persons were required to monitor for perchlorate for one year between 2001 and 

2003. A "statistically representative" number of additional smaller systems were also required to 

monitor for perchlorate for one year during this time period. However, with few exceptions, that 

monitoring data does not appear to have been reported to the State of New Mexico. Therefore, the 
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Environment Department has only a very incomplete picture of perchlorate contamination in public 

water systems in the State. 

Response: EPA has made the UCMR monitoring data publicly available. EPA has determined that 

this data is the best available data (collected in accordance with accepted methods) on the 

occurrence of perchlorate nationally. 
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EPA Comment Code: 3140 UCMR 1 entry-point-level estimation of perchlorate 

exposure 

Individual Comments 

Commenter Name: Caroline Baier-Anderson, PhD 

Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20952 

EPA Comment Code: 3140 

Comment: Perchlorate is Present at Sufficient Levels and Frequency to Constitute a Public Health 

Concern 

EPA's determination of whether perchlorate is present at sufficient levels and frequency to 

constitute a public health concern begins with an analysis of occurrence and population estimates 

for perchlorate at various thresholds. Since the data on occurrence may not represent water samples 

delivered to the entire service population, EPA considers two values fore each threshold or cutpoint considered (e.g., 4, 5, 7, 10, 12, 15, 17, 20 and 25 ug/L); the first value is the service 

population, and the second is an estimate below the service population, that is derived from the 

service population divided by the number of entry or sample points. The second value is in all cases 

substantially lower than that of the service population. To ensure the protection of public health, we 

recommend that the more conservative number - that of the entire service population - should be 

considered as the potentially impacted population. 

Response: EPA has decided to regulate perchlorate in drinking water. See response to comment 

code 6120. In the Federal Register notice “Final Regulatory Determination on Perchlorate” EPA 

considers a range of estimates of the population served by PWSs that had at least one sample with 

perchlorate concentrations greater than the potential HRLs. The population range represents both a 

high end estimate, as well as a central value estimate. The high end estimate is derived by adding the 

entire system population of all PWSs in which at least one sample was found to contain perchlorate 

above thethreshold. EPA considers this a high end estimate because it is based on the assumption 

that the entire system population is served water from the entry point that had the highest reported 

perchlorate concentration. In fact, many PWSs have multiple entry points into which treated water is 

pumped for distribution to their consumers. For the PWSs with multiple entry points, it is unlikely 

that the entire service population receives water from the one entry point with the highest single 

concentration. Therefore, EPA also provides a central value estimate of the population served water 

with perchlorate above a threshold. EPA developed this central value estimate by assuming the 

population was equally distributed among all entry points and added only the proportion of the total 

population served by those entry points in a PWS that had at least one sample with perchlorate 

concentrations greater than the threshold. EPA considered both the high end estimate and central 

value estimate in making this final regulatory determination. The Agency considered the central 

value estimate as well because this is likely a better estimate of the population exposed to perchlorate 

at levels of public health concern. 

Commenter Name: Shannon Cunniff 

Commenter Organization: Department of Defense (DOD) 
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EPA Document ID: EPA-HQ-OW-2009-0297-0411 

EPA Comment ID: 28525 

EPA Comment Code: 3140 

Comment: Comment No. 14 

Section III. B. 3. Alternative Approaches for Calculating HRLs 

Page & Paragraph Page 41889 Table 3 

Comment Example of comment # 2: In the use of the UCMR 1 data, the EPA indicates that an 

adjustment was made for water systems with multiple entry points to decrease the estimated 

population exposed to the "threshold of interest." However, in reviewing the outcome of this 

analysis (Table 3, EPA 2009), the reviewer is unable to readily duplicate the adjusted population 

estimates provided. 

Suggested Action, Revision and References (if necessary) The Table 3 values need to be reviewed 

and insured to be readily duplicable by external reviewers. 

Category* E 

Response: A more detailed description of the methodology for conducting a proportional 

population analysis of UCMR 1 data, such as the analysis used to derive the population estimates for 

entry or sample points having at least one detection greater than the threshold of interest in column 

five of Table 3 of the August 2009 FR Notice, can be found in the document titled “The Analysis 

Of Occurrence Data From The First Unregulated Contaminant Monitoring Regulation (UCMR 1) 

In Support Of Regulatory Determinations For The Second Drinking Water Contaminant Candidate 

List” in docket number EPA–HQ–OW–2007–0068. Please refer to the Proportional Populations 

Section of this document under Section 4.3 “Sample-Point-Level Analyses”. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection (MassDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0495 

EPA Comment ID: 28866 

EPA Comment Code: 3140 

Comment: We also wish to note that the population estimates in column 5 of Table three would be 

likely to underestimate those exposed in MA, and quite likely other states, due to mixing of supplies 

from multiple entry points. 

Response: Please see the response to comment ID 20952 in comment code 3140. In addition to the 

central value population estimates provided in the “Final Regulatory Determination on Perchlorate” 

notice, EPA also considered estimates of the total population served by drinking water systems in 

which at least one sample was found to contain perchlorate above the threshold (i.e., the high end 

estimate) to account for the mixing of supplies from multiple entry points to the distribution system. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group (EWG) 
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EPA Document ID: EPA-HQ-OW-2009-0297-0499 

EPA Comment ID: 28933 

EPA Comment Code: 3140 

Comment: Occurrence analysis: EPA's occurrence analysis grossly underestimates the number of 

people at risk from perchlorate because of an inappropriately high detection and reporting threshold 

of four ppb. 

In table 3 of the notice in the federal register, the Agency lists the occurrence and population 

estimates for perchlorate above a number of thresholds, starting at 4ppb. This data is derived from 

the Agency's Unregulated Contaminant Monitoring Rule (UCMR) 1; the Agency estimates that a 

total of 16.6 million people in the United States are served by public water systems with at least 1 

detection of perchlorate at > 4 ppb. 

In table 2 of the federal register, the agency finds that HRLs as low as 1 are necessary to prevent 

children ages two and younger who have higher water ingestion rates and cumulative perchlorate 

exposures that can easily exceed the RfD. In addition, as mentioned above, the degree of perchlorate 

contamination of some powdered infant formulas is so high than an HRL as low as 0 is justified for 

infants six months and younger. Therefore, the finding of perchlorate in drinking water at any level 

presents risks to vulnerable populations and until the minimum reporting level (MRL) is decreased 

to reflect this, the agency's numbers are an underestimate. 

Response: EPA acknowledges that there are newer and more sensitive analytical methods that are 

now available that would permit perchlorate analysis with reporting limits below 4 ug/L (the MRL 

for perchlorate under the UCMR 1 was 4 ug/L); however, the 1996 amendments to the Safe 

Drinking Water Act require the Agency to consider the best available, peer reviewed science when 

developing drinking water standards. In applying these principles, "best available" usually refers to 

the availability at the time an assessment is made. EPA derived potential alternative HRLs for 14 life 

stages (age groups) using the RfD and life stage-specific exposure information in the August 9, 2009, 

notice (74 FR 41883; USEPA 2009b). As part of the rulemaking process, EPA plans further analyze 

perchlorate occurrence data to estimate the additional number of PWSs and entry points and the 

population served at levels of public health concern. 
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EPA Comment Code: 3150 Potential use of a Bayesian model to estimate 

number of PWSs and population served at a range of thresholds 

Response to Code 3150: EPA continues to evaluate the utility of the Bayesian model(s) in the 

development of a NPDWR for perchlorate. EPA plans to be transparent in explaining the analysis 

and any assumptions made when presenting the analysis in connection with the proposed NPDWR. 

EPA does not intend to distinguish the source of perchlorate in drinking water but does intend to 

assess the number of water systems impacted by a potential regulation. 

Individual Comments 

Commenter Name: James D. Taft 

Commenter Organization: Association of State Drinking Water Administrators 

EPA Document ID: EPA-HQ-OW-2009-0297-0525 

EPA Comment ID: 28500 

EPA Comment Code: 3150 

Comment: a. EPA requests comment on the potential use of a Bayesian model to estimate the 

number of public water systems, and populations served by such systems, with at least one estimated 

sample detection greater than 1, 2, 3, 4, 5, 7, 10, 12, 15, 17, 20, and 25 [mu]g/L. 

ASDWA feels that it is necessary to do further modeling to estimate perchlorate levels below the 

analytical method MRL used in the UCMR monitoring and the Baysean modeling approach 

discussed in the notice strikes us as a reasonable one. Data from Massachusetts with a lower 

detection limit can be used to refine and validate the modeling so that more precise estimates can be 

made of occurrence at these very low levels. EPA should also include any new data received as a 

result of this notice in its analysis. 

Response: See response to comment code 3150. EPA has reviewed other occurrence data. 

Commenter Name: Kay Brothers 

Commenter Organization: Southern Nevada Water Authority 

EPA Document ID: EPA-HQ-OW-2009-0297-0667 

EPA Comment ID: 28694 

EPA Comment Code: 3150 

Comment: September 17, 2009 

Water Docket Environmental Protection Agency Mailcode: 2822T 1200 Pennsylvania Ave., NW 

Washington, DC 20460 

SUBJECT: Comments on the Drinking Water: Perchlorate Supplemental request for Comments 

Docket ID No. EPA-HQ-OW-2009-0297 

The Southern Nevada Water Authority (Authority) appreciates the opportunity to comment on the 

preliminary regulatory determination for perchlorate as listed in the August 19, 2009 Federal 

Register (74 FR 41883). The Authority is a cooperative agency formed in 1991 to address Southern 
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Nevada's unique water needs on a regional basis. Officials of the Authority are charged with 

managing the region's water resources and providing for approximately 2 million area residents' 

present and future water needs. The Authority is governed by a seven- member board comprised of 

representatives from each of its member agencies, which include the cities of Boulder City, 

Henderson, Las Vegas and North Las Vegas, as well as agencies serving customers in 

unincorporated Clark County and the town of Laughlin. 

The Authority's responsibilities include managing water supplies available to Southern Nevada and 

regional conservation programs as well as building and operating regional facilities to provide a 

reliable drinking water delivery system to all member agencies. 

Interpretation of the Physiologically-Based Pharmacokinetic (PBPK) Modeling 

The Authority strongly encourages the use of sound science in the consideration of federal 

regulation of perchlorate. While modeling such as the PBPK and Bayesian hierarchical models 

suggested in the noted Federal Register (FR) are of value when empirical data are unavailable, the 

use of these models for the elucidation of health reference levels and national occurrence, 

respectively, are not necessary as sufficient data already exist. 

Response: EPA continues to evaluate the utility of the Bayesian model(s) in the development of a 

NPDWR for perchlorate. EPA plans to be transparent in explaining the analysis and any 

assumptions made when presenting the analysis in connection with the proposed NPDWR. See 

response to comment code 3150. 

Commenter Name: Kay Brothers 

Commenter Organization: Southern Nevada Water Authority 

EPA Document ID: EPA-HQ-OW-2009-0297-0667 

EPA Comment ID: 28698 

EPA Comment Code: 3150 

Comment: Occurrence Analysis 

The Authority also does not support the use of Bayesian hierarchical models to extrapolate the 

Massachusetts' occurrence data to develop a portrait of sub-4 ug/L perchlorate occurrence 

nationwide. While we understand the great value of Bayesian models, we see no reason for applying 

these models considering that the preponderance of data suggest that perchlorate is not relevant to 

human health even at 4 ug/L and considering the inappropriateness of applying a relative source 

contribution (RSC) factor to perchlorate when using the Greer study or others where dietary 

contributions have already been accounted. Moreover, other studies have already shown that 

perchlorate is ubiquitous in the environment at concentrations above approximately 0.050 ng/L 

(Rickman 2003; Richardson 2004; Snyder, Vanderford et al. 2005), owing largely to the atmospheric 

formation and subsequent deposition of perchlorate in rain (Dasgupta, Martinelango et al. 2005; 

Rajagopalan, Anderson et al. 2006). 

Response: See response to comment code 3150. EPA disagrees with the commenter’s view that 

perchlorate is not relevant to human health even at 4 ug/L and that applying an RSC factor to 

perchlorate is inappropriate. See response to comment code 5220 for an explanation of EPA’s 
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rationale in concluding that perchlorate is relevant to human health at or below 4 ug/L. See 

response to comment code 5210 for an explanation of EPA’s use of an RSC. 

Commenter Name: Mic Stewart 

Commenter Organization: Water Quality Section, Metropolitan Water District of Southern 

California 

EPA Document ID: EPA-HQ-OW-2009-0297-0496 

EPA Comment ID: 28712 

EPA Comment Code: 3150 

Comment: Additional Comments on Occurrence Analysis and Potential Use of a Bayesian Model 

EPA has requested comments on the appropriateness of its exposure model to estimate the number 

of public water systems and populations served by such systems. The American Water Works 

Association and other water industry associations have suggested that the use of Bayesian modeling 

is not necessary to support the Agency's regulatory decision-making for perchlorate. Metropolitan 

suggests that any methodology employed by EPA to interpret occurrence data be consistent with 

other established methods used with other regulatory development. 

Response: EPA continues to evaluate the utility of the Bayesian model(s) in the development of a 

NPDWR for perchlorate. EPA plans to be transparent in explaining the analysis and any 

assumptions made when presenting the analysis in connection with the proposed NPDWR. See 

response to comment code 3150. 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 28746 

EPA Comment Code: 3150 

Comment: 3. Use of a Bayesian model for the purposes stated in the August 19, 2009 Federal 

Register requires additional justification as it will lead to an overestimation of the low-level 

occurrence of perchlorate if calibrated to select geographical areas and/or small data sets. 

Response: See response to comment code 3150. 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 28753 

EPA Comment Code: 3150 

Comment: C. Occurrence Analysis 4. Request for Comment on Alternative Approaches a. EPA 

requests continent on the potential use of a Bayesian model to estimate the number of public water 

systems, and populations served by such systems, with at least one estimated sample detection 

greater than 1, 2, 3, 4, 5, 7, 10, 12, 15, 17, 20, and 25 ug/L. 
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Comment C.4.a.1: Use of a Bayesian model for the stated purpose is not recommended nor 

supported by the NDEP. The NDEP understands that the national occurrence data for perchlorate 

were generated between 2001 and 2005. Further, we understand that EPA Method 314 was used for 

analysis of the occurrence data. The typical reporting limit associated with EPA Method 314 is 4 

ug/L. EPA required the collection and submittal of the national occurrence data knowing this 

limitation. 

It is not clear how use of a Bayesian model now for revaluating the existing occurrence data could 

be considered as a reasonably defensible approach for analysis. This is because it likely will lead to an 

overestimation of the low- level occurrence of perchlorate if calibrated to select geographical areas 

and/or small data sets. 

Response: See response to comment code 3150. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28808 

EPA Comment Code: 3150 

Comment: REQUEST FOR COMMENT ON ALTERNATIVE APPROACHES 

a. On the use of a Baysian model to estimate number of public water systems. 

NRDC response: NRDC has no opinion on this. 

Response: No response necessary 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28837 

EPA Comment Code: 3150 

Comment: 74 FR 41891: "EPA requests comment on the potential use of a Bayesian model to 

estimate the number of public water systems and populations served by such systems, with at least 

one estimated sample detection greater than 1, 2, 3, 4 ug/l, etc." 

The Bayesian extrapolation of UCMR1 occurrence data is a complex analysis and therefore EPA 

needs to be transparent in explaining the analysis in its final regulatory determination. AMWA 

requests that EPA also clearly state the assumptions of the modeling effort. AMWA recommends 

that the effort recognize that the data available shows that perchlorate occurrence is not evenly 

distributed across the country. 

Response: EPA continues to evaluate the utility of the Bayesian model(s) in the development of a 

NPDWR for perchlorate. EPA plans to be transparent in explaining the analysis and any 

assumptions made when presenting the analysis in connection with the proposed NPDWR. See 

response to comment code 3150. 
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Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0415 

EPA Comment ID: 28853 

EPA Comment Code: 3150 

Comment: Occurrence Analysis 

The Agency requested comments on the appropriateness of using a Bayesian model to estimate 

perchlorate occurrence in public water systems and populations served by such systems. This 

estimate would use UCMR1 data that had a laboratory detection level of 4 ug/L and project national 

occurrence at levels below 4 ug/L. While AWWA recognizes the validity of Bayesian modeling, we 

believe that the study as proposed is not necessary to support the Agency's regulatory decision 

making for perchlorate. The weight of evidence as discussed in our comments does not support the 

need for further analysis of occurrence since regulation of perchlorate would not present a 

meaningful opportunity for health risk reduction for persons served by public water systems. 

Response: The Agency has concluded that there is a meaningful opportunity for health risk 

reduction for persons served by public water systems through a National Primary Drinking Water 

Rule for perchlorate. EPA acknowledges that the use of Bayesian modeling is not necessary for 

making a regulatory determination on perchlorate. EPA continues to evaluate the utility of the 

Bayesian model(s) in the development of a NPDWR for perchlorate. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0415 

EPA Comment ID: 28854 

EPA Comment Code: 3150 

Comment: Multiple studies have presented data demonstrating that perchlorate is widely found at 

low levels and may originate from anthropogenic and/or natural sources; it even occurs in some 

dietary supplements [FN14: Snyder, S., Pleus, R., Vanderford, B., J. Holady. 2006. Perchlorate and 

chlorate in dietary supplements and flavor enhancing ingredients. Analytica Chimica Acta, 567:1:26.] 

and groundwater more than 28,000 years old [FN15: Plummer, L. N.; Bohlke, J. K.; Doughten, M. 

W. 2006. Perchlorate in pleistocene and holocene groundwater in North-Central New Mexico. 

Environ. Sci. Technol. 40:1757.]. Since the major route of exposure is food and not water, 

estimating low level concentrations of perchlorate in the minor source will not provide any 

additional useful information. The only reason to determine perchlorate concentrations in water is to 

estimate human exposure. Given the previous discussion and the Agency's assessments, there clearly 

is sufficient data from human studies that have been completed to sufficiently characterize exposure. 

These studies (e.g. NHANES, FDA Total Diet Study) examined urine, saliva, and breast milk and in 

all cases the study subjects had perchlorate. There were no studied individuals who did not have 

perchlorate. So we know that in the U.S., exposure to perchlorate is very close to universal. Further, 

examination [FN16: Brandbuber , P, Clark, S. and K. Morley. (publication pending) The Occurrence 

of Perchlorate in Public Drinking Water Systems, Journal AWWA.] of the existing UMCR dataset 

provides no general indicator of a causal relationship between occurrence and known locations of 

perchlorate releases with exception of locations at extremely high levels that were typically adjacent 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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to industrial and military users of perchlorate. In the vast majority of UCMR occurrences, an 

obvious source could not be easily identified. Studies [FN17: Jackson, W., Rainwater, K., Anderson, 

T., Lehman, T., Tock, R., Rajagopalan, S., and M. Ridley. 2004. Distribution And Potential Sources 

Of Perchlorate In The High Plains Region Of Texas Final Report. Submitted to the Texas 

Commission on Environmental Quality.],[FN18: Duncan, P.B, Morris, R.D., and E. Vavricka. 2005. 

Forensic identification of anthropogenic and naturally occurring source of perchlorate. 

Environmental Forensics, 6:205-215.],[FN19: Dasgupta, P., Martinelango, P., Jackson, W., 

Anderson, T., Tian, K., and R. Tock. 2005. The Origin of Naturally Occurring Perchlorate: The Role 

of Atmospheric Processes Environ. Sci. Technol., 39:6:1569 -1575.],[FN20: Balaji Rao, Todd A. 

Anderson, Greta J. Orris, Ken A. Rainwater,* Srinath Rajagopalan, Renee M. Sandvig, Bridget R. 

Scanlon, David A. Stonestrom, Michelle A. Walvoord, and W. Andrew Jackson (2007) Widespread 

Natural Perchlorate in Unsaturated Zones of the Southwest United States Environ. Sci. Technol, 

41:4522-4528.] of natural occurrence also do not provide a sound basis for predicting occurrence of 

perchlorate, unlike other inorganic substances that may associate with specific geological formations 

such as radionuclides and arsenic. 

The Agency has proposed a statistical Bayesian procedure to estimate the distribution of censored 

perchlorate data. There are several different such procedures (Maximum Likelihood Estimate, 

Kaplan-Meier Non-Parametric techniques, Regression on Order Statistics) however that all make 

assumptions about the nature of the distribution, whether normal, log-normal, or non-normal. The 

Agency has not explained why this particular model would be used versus one of the other 

approaches noted here. Nor does the Agency explain what population distribution is being assumed. 

Without this information, it is impossible to comment on the validity of the proposed procedures 

for this or potentially future applications of this approach. Regardless, all such procedures must 

assume that a single population of results is being estimated. However there appear to be multiple 

populations of results, those resulting from natural sources, munitions, Chilean fertilizers, etc. There 

may, of course, be more than one natural source as cited in the studies previously noted. Given the 

fact that the occurrence data is mostly poly-modal due to multiple sources in areas such as California 

and Massachusetts, the use of any statistical procedure that is based on a mono-modal distribution 

will have little likelihood of producing useful results. 

Response: See response to comment code 3150. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection (MassDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0495 

EPA Comment ID: 28865 

EPA Comment Code: 3150 

Comment: Section III C: Occurrence Analysis 

4(a)) EPA's proposal to use a Bayesian model to estimate the number of public water systems, and 

populations served by such systems, with sample detections at various levels appears to be a 

reasonable approach. Further details regarding the specific model inputs are, however, needed in 

order to assess the usefulness of the model. MassDEP will provide U.S. EPA with Massachusetts 

perchlorate monitoring data to assist in this effort. However, we wish to note that the sampling 

results and data distribution for MA may not reflect the situation in other states. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Response: EPA appreciates MassDEP’s offer to provide EPA with Massachusetts perchlorate 

monitoring data and acknowledges that MA’s sampling results and data distribution may not be 

representative of other states. See response to comment code 3150. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28891 

EPA Comment Code: 3150 

Comment: 1. EPA requests comment on the potential use of a Bayesian model to estimate the 

number of public water systems, and the population served by such systems, with at least one 

estimated sample detection greater than 1, 2, 3, 4, 5, 7, 10, 12, 15, 17, 20, and 25 ug/L. 

With regard to perchlorate's regulatory determination, extrapolating the frequency of occurrence of 

perchlorate in U.S. drinking water at concentrations less than the MRL of 4 ug/L is unnecessary 

because scientific data provide no evidence that adverse health effects can occur at these levels. Data 

for average adults (e.g., Greer et al., 2002) suggest that IUI at water concentrations less than 245 ppb 

(the drinking water equivalent of the POD) would be statistically insignificant, and the Notice 

suggests, based on EPA's PBPK model for several life stages, that IUI at water concentrations 

corresponding to the RfD (i.e., 24.5 ppb) would be less than 2%. 

Further, UCMR1 data are insufficient for estimating population sizes exposed to concentrations 

greater than the MRL of 4 ug/L, and therefore may not be used to reliably estimate exposures below 

the MRL. As elaborated below, examination of EPA's occurrence analysis is made difficult by the 

fact that the Notice lacks the required transparency concerning the assumptions it used to calculate 

sizes of populations potentially exposed to different threshold concentrations (Table 3, U.S. EPA, 

2009b). The Notice's summary of the UCMR1 data likely overestimates current exposure 

concentrations and the number of people exposed to perchlorate above various threshold levels. 

Response: See response to comment code 3150. See response to comment code 5220 for an 

explanation of EPA’s rationale in concluding that adverse health effects occur at levels below 24.5 

ppb. EPA believes that UCMR1 data are sufficient for estimating population sizes exposed to 

concentrations greater than the MRL of 4 ug/L. See response to comment ID 28525 under 

comment code 3140 for an explanation of the EPA’s population analysis of UCMR 1 data. 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0527 

EPA Comment ID: 28913 

EPA Comment Code: 3150 

Comment: We support the use of Bayesian statistical models and approaches to estimate the 

occurrence of perchlorate in public water systems and the number of people exposed at 

concentrations below the minimum reporting level (MRL) in the occurrence studies on which the 

analysis is based. Response: See response to comment code 3150. 

Commenter Name: Danielle Blacet 
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Commenter Organization: Association of California Water Agencies 

EPA Document ID: EPA-HQ-OW-2009-0297-0208 

EPA Comment ID: 28925 

EPA Comment Code: 3150 

Comment: 3) Potential use of Bayesian model (page 41891) 

ACWA feels that the Bayesian model would not be useful for the purposes of this determination as 

we already know that at low enough concentrations perchlorate is widely found, if not ubiquitous. 

Dr. Shane Snyder and others have completed research that indicates perchlorate exists in basically 

every water source studied and that US exposure to perchlorate is very close to universal. Several 

human exposure studies (e.g. NHANES) have also looked at urine, saliva, and breast milk and every 

single study subject in each study had perchlorate--there were no studied individuals who did not 

have perchlorate. Estimating this data is not necessary when real data is already available. 

In addition, since the major route of exposure is food and not water, estimating low level 

concentrations of perchlorate in the minor source will not provide any additional useful information 

to determine if this chemical needs to be regulated. 

Further, while the USEPA is proposing to use a statistical Bayesian procedure to estimate the 

distribution of censored perchlorate data, it has not been explained why this particular model would 

be used and not some other model nor do they explain what population distribution is being 

assumed. However, all such procedures must assume a single population of results being estimated. 

In the case of perchlorate, there appear to be multiple populations of results, those resulting from 

potentially several distinct natural sources, munitions, and Chilean fertilizers. Given the fact that the 

data should be poly-modal due to these multiple sources found in areas such as California and 

Massachusetts, the use of any statistical procedure that is based on a mono-modal distribution will 

have little likelihood of producing useful results. 

Again, ACWA appreciates the opportunity to submit comments on this critical determination, and 

USEPAâ€TMs efforts to protect public health through the provisions of the federal Safe Drinking 

Water Act. We trust USEPA will consider all of the good science that is available when making a 

final regulatory determination. 

If you have any questions, please feel free to call our offices at 916-441-4545 or 202-434- 4760. 

Sincerely, 

Danielle Blacet Regulatory Advocate 

Abby Schneider, Ph.D. Federal Legislative Representative 

Response: EPA did not use the Bayesian model to make the regulatory determination on 

perchlorate. EPA continues to evaluate the utility of the Bayesian model(s) in the development of a 

NPDWR for perchlorate. EPA may not necessarily distinguish the source of perchlorate in drinking 

water but does intend to assess the number of water systems impacted by a potential regulation. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 3160 Use of Census data to estimate populations that are 

in the sensitive life stage 

Individual Comments 

Commenter Name: James D. Taft 

Commenter Organization: Association of State Drinking Water Administrators 

EPA Document ID: EPA-HQ-OW-2009-0297-0525 

EPA Comment ID: 28501 

EPA Comment Code: 3160 

Comment: b. EPA requests comment on using U.S. Census data to estimate the portions of the 

population that are in the sensitive life stage at any one time. 

US Census data are appropriate to estimate the population numbers for subpopulations that may be 

more vulnerable to perchlorate. As mentioned above, if sensitive subpopulations are going to be 

considered when making the regulatory determination, accurate estimates of how many people will 

be protected are critical to the decision. 

Response: Please see the response to comment ID 28809 in comment code 3160. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28809 

EPA Comment Code: 3160 

Comment: b. On the use of US Census data to estimate portions of the population that are in the 

sensitive life stage at any one time 

NRDC response: Yes, the U.S. Census data is appropriate for this use. 

Yes, EPA should use the U.S. census data. The U.S. census is mandated by the U.S. Constitution, 

and is conducted every 10 years, with the next one planned for 2010. These data are used by 

Congress, as well as governments at the local, state, and tribal level to make important decisions 

about setting priorities, providing services, disbursing funds, and even distributing Congressional 

seats.[FN62: See e.g. http://2010.census.gov/2010census/] The census data are widely recognized 

to be reliable, credible, and useful. 

There is a valid concern that these data under-represent certain populations, such as certain ethnic 

minorities, who may be "unregistered" for census purposes. This may be relevant to the use of these 

data for this perchlorate assessment, because the children of ethnic minorities may not be fully 

represented. If anything, these data would underestimate the number of children under 1 year old. 

Response: Please see response to comment ID 28867 under comment code 3160. EPA will further 

take into consideration the effect contaminants have on sensitive life stages that comprise a 

meaningful portion of the general population (such as infants, children, pregnant women, the 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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elderly, and individuals with a history of serious illness) as we develop the proposed NPDWR, as 

required by Section 1412(b)(1) of the Safe Drinking Water Act. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection (MassDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0495 

EPA Comment ID: 28867 

EPA Comment Code: 3160 

Comment: 4(b)) EPA requested comments on using US Census data to estimate the portions of the 

population that are sensitive at any one time to perchlorate in drinking water. This analysis is used as 

one factor in EPA's decision-making on the need for a drinking water standard for perchlorate, 

based on the number of people in the U.S. who would be at risk. MassDEP believes that it is 

inappropriate to consider sensitive groups one-by-one using census or any other data. EPA should 

certainly consider perchlorate exposures to fetuses, infants and young children up to 2 years of age. 

However, EPA should also, for several reasons, consider the entire population's exposure. First, 

Blount et al. (2006) and Steinmaus et al. (2007) reported an association between perchlorate 

exposure and decreased T4 and increased TSH in iodine deficient adult women and increased TSH 

in all women. As such, we believe that all women should be included in EPA's analysis as a sensitive 

subgroup. Secondly, as previously noted, there are other sensitive members of the population 

beyond fetuses, infants and women, and they should also be factored into EPA's framework for 

considering the extent of the population at risk to perchlorate exposures from drinking water. Lastly, 

because significant exposures to other thyroid toxicants are known to occur, other members of the 

population may also be at increased risk. Thus, any estimate derived based on exposures to the fetus, 

neonate and women as a group will still be an underestimate of those actually at risk. 

We appreciate the opportunity to comment. For further information please contact Carol Rowan 

West at 617-292-5510 (Carol.RowanWest@state.ma.us), C. Mark Smith at 617-292-5509 

(C.Mark.Smith@state.ma.us) or Tsedash Zewdie at (617) 292-5842 (Tsedash.Zewdie@state.ma.us). 

References 

Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell KL. 2006. Urinary perchlorate and 

thyroid hormone levels in adolescent and adult men and women living in the United States. Environ 

Health Perspect 114:1865-1871. 

Ginsberg GL, Hattis DB, Zoeller RT, Rice, DC. 2007. Evaluation of the U.S. EPA/OSWER 

preliminary remediation goal for perchlorate in groundwater: focus on exposure to nursing infants. 

Environ Health Perspect 115:361-369. 

Glinoer D. 2001. Pregnancy and iodine. Thyroid 11:471-481. 

Greer MA, Goodman G, Pleus RC, Greer SE. 2002. Health effects assessment for environmental 

perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake 

inhumans. Environ Health Perspect 110:927-937. 

Iglesias P and Diez JJ (2009). Thyroid dysfunction and kidney disease. Eur J of Endocrinol 160: 503-

515 
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McLanahan ED, Andersen ME, Campbell Jr. JL, Fisher JW. 2009. Competitive inhibition of 

thyroidal uptake of dietary iodide by perchlorate does not describe perturbations in rat serum total 

T4 and TSH. Environ Health Perspect 117(5):731-738. 

Miller M, Crofton KM, Rice DC, Zoeller T (2009). Thyroid disrupting chemicals: Interpreting 

upstream biomarkers of adverse outcomes. Environ. Health. Perspect. 117:1033-1041. 

Steinmaus C, Miller MD, Howd R. 2007. Impact of smoking and thiocyanate on perchlorate and 

thyroid hormone associations in the 2001-2002 national health and nutrition examination survey. 

Environ Health Perspect 115:1333-1338. 

Response: EPA considered the population estimates served by PWSs that were monitored under 

UCMR 1 for which the highest reported perchlorate concentration was greater than various 

threshold concentrations when determining that a regulation for perchlorate was warranted. These 

population estimates are for people at all life stages. EPA has determined that a NPDWR for 

perchlorate could reduce perchlorate exposures for these populations to levels below the potential 

alternative HRLs that EPA has identified as levels of public health concerns for purposes of this 

determination, and that such exposure reductions present a meaningful opportunity for the 

reduction of health risks for persons served by PWSs. Please see the final regulatory determination 

notice for further discussion of this analysis. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28893 

EPA Comment Code: 3160 

Comment: 2. EPA requests comment on using U.S. Census data to estimate the portions of the 

population that are in the sensitive life stage at any one time. 

U.S. Census data might be useful if PWS data are paired with U.S. Census data for the same 

locations. As discussed above, the relevance of the UCMR1 data to current exposure is unclear since 

the UCMR1 data, which were collected from 2001 to 2005, likely overestimate current 

concentrations, and approximately half of the perchlorate water samples in the UCMR1 database are 

from untreated source waters. Evaluating perchlorate in drinking water at low concentrations (e.g., 

less than the concentration corresponding to the RfD of 24.5 ppb) is unnecessary as no adverse 

health effects are expected at these levels. 

Response: 

Please see response to comment ID 28809 under comment code 3160. 

EPA acknowledges that there may be sources that had detected perchlorate from UCMR1 

monitoring that are either no longer being used or are being treated per the requirements of 

maximum contaminant levels established in California and Massachusetts; however, the 1996 

amendments to the Safe Drinking Water Act require the Agency to consider the best available, peer 

reviewed science when developing drinking water standards. In applying these principles, "best 

available" usually refers to the availability at the time an assessment is made. UCMR data is the most 
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extensive nationally representative occurrence data for perchlorate in public water systems; 

therefore, EPA analyzed this data and additional occurrence data in making a regulatory 

determination for perchlorate as required by SDWA Section 1445. 

EPA disagrees with the commenter that approximately half of perchlorate water samples in the 

UCMR 1 database are from untreated source waters. The data EPA used to evaluate perchlorate 

occurrence from UCMR1 was only taken from finished water. EPA did allow monitoring at source 

water sampling points; however, if perchlorate was detected in a source water sample, the UCMR 1 

required that follow-up samples be collected at the entry point to the distribution system and follow 

the monitoring frequency specified in the rule for the contaminant and water source type. 

EPA disagrees that evaluating perchlorate in drinking water at low concentrations (e.g., less than the 

concentration of 24.5 ppb) is unnecessary. Since the NRC also identified infants and developing 

children as additional life stages, EPA derived potential alternative HRLs for 14 life stages (age 

groups) using the RfD and life stage-specific exposure information in the August 9, 2009, notice (74 

FR 41883; USEPA 2009b). These levels range from 1 μg/L to 47 μg/L and are the concentrations 

of perchlorate in drinking water that may result in total perchlorate exposures (from food and water) 

greater than the RfD for individuals at each life stage. EPA is evaluating these potential alternative 

HRLs and considers them to be levels of public health concern for purposes of this determination. 

For further discussion of this issue please see today’s notice. 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0527 

EPA Comment ID: 28914 

EPA Comment Code: 3160 

Comment: We also support the use of U.S. Census data to estimate the numbers of pregnant 

women, infants, and children. 

Response: Please see the response to comment ID 28809 in comment code 3160. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 3170 Accounting for variation of perchlorate levels in 

public water systems over time 

Response to Code 3170: EPA has decided to regulate perchlorate in drinking water. See response 

to comment code 6120. EPA notes that systems or entry/sample points with at least one detect 

above the threshold may not expose the population to this level at all times. At any particular time, 

perchlorate levels may be lower or higher than the highest estimated sample detection. However, 

EPA believes that estimating the number of systems, entry points and populations with at least one 

detection above the various threshold concentrations identified in the final perchlorate regulatory 

determination notice is appropriate for the perchlorate regulatory determination because a single 

quarterly or semi-annual sample more closely reflects the short term exposure during the life stages 

identified by the NRC (i.e., fetuses, pre-term newborns, infants and young children) than does the 

estimated mean concentration of perchlorate at a system. 

Individual Comments 

Commenter Name: James D. Taft 

Commenter Organization: Association of State Drinking Water Administrators 

EPA Document ID: EPA-HQ-OW-2009-0297-0525 

EPA Comment ID: 28502 

EPA Comment Code: 3170 

Comment: c. EPA requests comment on how the Agency should account for the variation of 

perchlorate levels over time in public water systems. EPA believes that estimating the number of 

systems, entry points and populations with at least one detection above the HRL is appropriate for 

the perchlorate regulatory determination because a single quarterly or semi- annual sample more 

closely reflects the short term exposure during life stages of concern (i.e., fetuses, pre-term 

newborns, infants and young children). However, EPA requests comment on whether the Agency 

should consider other approaches such as estimating the number of systems, entry points and 

populations with two or more detections above HRL or some other approach. 

ASDWA agrees with EPA's premise that a single occurrence above the HRL could indicate a cause 

for concern about health impacts due to short term exposure, if the value is not an anomaly. 

However, on the other hand, a single value above the HRL, especially if the HRL is 15 ug/l or 

almost 4 times the MRL, that is not supported by additional detections in other samples, could be 

questionable and indicative of a sampling or laboratory error. EPA should consider an analysis that 

considers a single sample above the HRL, but with additional detects, as the occurrence criteria. This 

considers the impact of short term possible health impacts but would tend to eliminate outliers. 

Response: See response to comment code 3170. EPA intends to present the perchlorate occurrence 

analysis that is used to develop the NPWDR. 

Commenter Name: Kathy Dolan 

Commenter Organization: Food and Water Watch (FWW) 

EPA Document ID: EPA-HQ-OW-2009-0297-0526 

EPA Comment ID: 28611 

EPA Comment Code: 3170 
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Comment: You also request comment on how the Agency should account for variation of 

perchlorate levels over time in public water systems. This is simple: the Agency should act with 

extreme precaution. 

Response: See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #11 - Food and Water Watch 

EPA Document ID: EPA-HQ-OW-2009-0297-0526 

EPA Comment ID: 28617 

EPA Comment Code: 3170 

Comment: You also request comment on how the Agency should account for variation of 

perchlorate levels over time in public water systems. This is simple: the Agency should act with 

extreme precaution. 

Response: See response to comment code 6120. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28810 

EPA Comment Code: 3170 

Comment: c. On how the Agency should account for the variation of perchlorate levels over time, 

based on estimating the number of systems, entry points and sampling. 

NRDC Response: If EPA plans to consider the low-end estimate of the population exposed, it must 

develop a justifiable estimate. 

As part of the occurrence analysis, EPA attempted a high-end and a low-end estimate of the 

population exposed to perchlorate from contaminated drinking water. The high-end estimate, which 

is the population served by a system with a contaminated entry-point is an appropriate point to use. 

However, EPA did not employ the best method to estimate population exposure for the low-end 

estimate. For systems with multiple entry points, EPA estimated an equal proportion of the 

population was served by each entry point. However, EPA acknowledged that "[t] his approach may 

provide either an overestimate or an underestimate of the population served by the affected entry 

point" but failed to provide any reasonable uncertainty analysis. An uncertainty analysis is a 

mathematical measure of the "goodness" of the result, and therefore our confidence in it. With such 

an analysis it is impossible to determine the fitness of the value as a basis for making regulatory 

decisions related to health protection or scientific quality. Therefore, EPA cannot justify using this 

estimate to model the occurrence of and exposure to perchlorate in drinking water. 

There are two problems with assuming that every entry point equally serves a population. First, it is 

possible that one entry point could serve a large majority of the population and other entry points 

serve many fewer. Basing the estimate on the proportion of the flow rate of water sent to the system 

by a given entry point would provide a more accurate representation of the population exposed. 

Second, having a detection at one entry point does not preclude the possibility that other entry 

points in the system are also contaminated. For example, one groundwater source may distribute 
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water to multiple wells which separately contribute water to a system. Therefore, assuming that one 

contaminated entry point contributes equally to the flow of the entire distribution system is a weak 

way to estimate the population exposed. Because EPA can neither determine whether this 

estimation is an overestimate or an underestimate, or provide an analysis of the uncertainty, it should 

not be used as part of the regulatory determination for perchlorate. 

NRDC Response: Estimating the water systems with at least one entry point with a sample above 

the detection limit is appropriate for the perchlorate regulatory determination. 

The perchlorate monitoring program was not designed to specifically detect high levels of 

perchlorate. While we are not aware of evidence that there are large fluctuations of perchlorate levels 

in groundwater, detecting perchlorate in drinking water is a signal of a bigger, not smaller, 

contamination problem. When sporadic sampling is conducted in a system - such as taking a single 

quarterly or semi-annual sample - detections of contamination are a reflection of a widespread 

problem. It much more likely that a monitoring program would miss detections and particularly 

elevated spikes, rather than catch them. Much like searching for a needle in a haystack,if you find 

one, it is likely because there are many more; however if you don't find one, that does not mean 

there are none. Therefore, each finding of contamination in monitoring data should be treated 

seriously, as if it is representative of a widespread problem. 

Response: For a discussion on variation of perchlorate levels over time see response to comment 

code 3170. For a discussion of the analysis EPA used to derive the population estimates that EPA 

considered in the final regulatory determination see response to comment ID 28525 under comment 

code 3140. EPA believes that an uncertainty analysis is unnecessary due to the fact that the Agency 

not only considered central value estimates, as the commenter requested, but the Agency evaluated 

high end estimates as well. Please see response to comment ID 20952 under comment code 

3140.which explains in detail what EPA did to account for high and low end population estimates. 

EPA agrees that each finding of contamination should be taken seriously and that is part of the 

reason that we have determined that perchlorate occurs or there is a substantial likelihood that 

perchlorate will occur with a frequency and at levels of public health concern in public water 

systems. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28894 

EPA Comment Code: 3170 

Comment: 3. EPA requests comment on how the Agency should account for the variation of 

perchlorate levels over time in public water systems. EPA believes that estimating the number of 

systems, entry points and populations with at least one detection above the HRL is appropriate for 

the perchlorate regulatory determination because a single quarterly or semiannual sample more 

closely reflects the short term exposure during life stages of concern (i.e., fetuses, preterm newborns, 

infants and young children). However, EPA requests comment on whether the Agency should 

consider other approaches such as estimating the number of systems, entry points and populations 

with two or more detections above HRL or some other approach. 
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As discussed above, there are fundamental scientific and statistical issues with the UCMR1 database 

for estimating current exposures to perchlorate in drinking water, so any application of the data 

therein would be unreliable. First, UCMR1 data are likely to overestimate current exposure 

concentrations because data were collected from 2001-2005 and subsequent remediation and 

treatment has reduced these concentrations, and approximately half of the perchlorate water samples 

in the UCMR1 database are from untreated source waters. Second, data in the UCMR1 database are 

insufficient for estimating population sizes because, for PWSs with multiple entry points to the 

distribution system, the database does not specify the size of subpopulations distributed water from 

specific entry points where perchlorate was detected. 

Response: EPA acknowledges that there may be sources that had detected perchlorate from 

UCMR1 monitoring that are either no longer being used or are being treated per the requirements of 

maximum contaminant levels established in California and Massachusetts; however, the 1996 

amendments to the Safe Drinking Water Act require the Agency to consider the best available, peer 

reviewed science when developing drinking water standards. In applying these principles, "best 

available" usually refers to the availability at the time an assessment is made. UCMR data is the most 

extensive nationally representative occurrence data for perchlorate in public water systems; 

therefore, EPA analyzed this data and additional occurrence data in making a regulatory 

determination for perchlorate as required by SDWA Section 1445. 

EPA disagrees that data in the UCMR1 database are insufficient for estimating population sizes. 

EPA presents in today’s Federal Register notice a range of estimates of the population served by 

PWSs that had at least one sample with perchlorate concentrations greater than the threshold 

concentrations. The population range represents both a high end estimate, as well as a central value 

estimate, both derived using the UCMR 1 monitoring data. The high end estimate of the population 

served drinking water above a threshold is derived by adding the entire system population of all 

PWSs in which at least one sample was found to contain perchlorate above the threshold. Many 

PWSs have multiple entry points into which treated water is pumped for distribution to their 

consumers. For the PWSs with multiple entry points, it is unlikely that the entire service population 

receives water from the one entry point with the highest single concentration. Therefore, EPA also 

provides a central value estimate of the population served water with perchlorate above a threshold 

in today’s notice. EPA developed this central value estimate by assuming the population was equally 

distributed among all entry points and added only the proportion of the total population served by 

those entry points in a PWS that had at least one sample with perchlorate concentrations greater 

than the threshold. 

In regards to the commenter’s concern that approximately half of the perchlorate water samples in 

the UCMR1 database are from untreated source waters, please see response to comment ID 28893 

under comment code 3160. 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0527 

EPA Comment ID: 28915 

EPA Comment Code: 3170 

Comment: As discussed in the notice, short-term exposures during sensitive life stages are of 

concern for perchlorate. We agree that the short time frame of concern should be considered in 

evaluating perchlorate's occurrence. The NJDEP (2009) MCL proposal considers the short 
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timeframe of concern for perchlorate in its notification and monitoring requirements. If a public 

water system receives results of a sample which exceed the MCL, a confirmation sample must be 

taken within 72 hours, as opposed to within two weeks for contaminants with chronic health effects. 

Enforcement of the MCL will be based on the average of the initial sample and the confirmation 

sample. Also, public notification of an MCL violation must take place with 14 days, as opposed to 

30 days for contaminants ith chronic health effects. 

Because of the short time period of exposure that is of concern for perchlorate, we agree with 

USEPA that data for systems, entry points, and populations with at least one detection above the 

HRL should be used in the regulatory determination. We agree that it is appropriate to base the 

occurrence analysis for the regulatory determination on the maximum concentration detected rather 

than on the average concentration. 

Response: See response to comment code 3170. EPA agrees with the commenter in regards to 

basing the occurrence analysis on the maximum concentration detected. 
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EPA Comment Code: 3200 Supplemental drinking water occurrence data from 

California and Massachusetts 

Individual Comments 

Commenter Name: Pete McHugh 

Commenter Organization: Santa Clara County Board of Supervisors 

EPA Document ID: EPA-HQ-OW-2008-0692-0681 

EPA Comment ID: 20021 

EPA Comment Code: 3200 

Comment: Perchlorate is a contaminant found in drinking water in California and at least 34 other 

states. It interrupts the uptake of iodine in the thyroid and may adversely affect thyroid function, 

which can then interrupt many hormones in the body. Infants, children, and pregnant women are 

particularly vulnerable populations. 

As of 2005, there were 456 drinking water sources with perchlorate detections in 12 counties in 

California. In our county, an 18 square mile plume of perchlorate contamination requires the 

monitoring and remediation of hundreds of water wells. Although the source of Santa Clara 

County's perchlorate contamination and discharger has been identified, drinking water quality is not 

expected to return to baseline levels for at least 12 years at best. 

Response: Using the criteria mandated by the 1996 SDWA Amendments, EPA has determined that 

regulation of perchlorate in drinking water systems presents a meaningful opportunity to reduce 

health risk for persons served by public water systems. See response to comment code 6120. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28829 

EPA Comment Code: 3200 

Comment: Population Estimates 

AMWA agrees with EPA that its population estimate is high for systems with at least one 

perchlorate detection and multiple entry points into the distribution system. This is because EPA 

based the estimate upon the assumption that an entire system's population would be served water 

from the entry point with the perchlorate detection. However, in systems with multiple entry points, 

AMWA agrees it is unlikely that the system's entire service population would receive water that 

contains perchlorate at the highest concentration detected at a single entry point. 

In addition, AMWA agrees with comments referenced by EPA on page 41890 of the FR notice that 

some states have higher concentrations of perchlorate in drinking water than others. In addition, the 

exposure to perchlorate of the population in states that already have regulatory limits for perchlorate 

will be capped at those levels. For example, staff from the Massachusetts Department of 

Environmental Protection indicated to AMWA that it will possibly require the PWS with the highest 

concentration of perchlorate during the commonwealth's last compliance sampling round to shut 
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down its well and find a new source of water for its service population. Compliance data for the Los 

Angeles Department of Water and Power (Appendix A [see PDF docket ID EPA-HQ-OW-2009-

0494]) shows very few detections, with all samples below California's MCL of 6 ppb. 

With regard to UCMR data, many of the utilities in the southwest and western states with 

perchlorate detections have since seen their concentrations drop. Whether because of state 

standards, local cleanups at the Tronox (formerly Kerr McGee) facility or for other reasons, EPA 

must take this into consideration in its final population estimates. For example, SNWA had 

perchlorate detections in 2003 ranging from 10 - 17 ppb. Today the concentrations range from 1 to 

3 ppb. There are many utilities in CA and AZ that are served by Metropolitan Water District 

(MWD) of Southern California and the Central Arizona Project that had detections in the range of 3 

to 6 ppb in 2002 to 2004 that have not had detections of perchlorate in the last 2 years. For example, 

please see the data from Consumer Confidence Reports from Phoenix 

(http://phoenix.gov/ftpalias/payf/qualre05.pdf) and Scottsdale 

(http://www.scottsdaleaz.gov/AssetFactory.aspx?did=28404). In addition, AMWA is also providing 

annual average perchlorate concentrations from the Alfred Merritt Smith Water Treatment Facility 

(AMSWTF) at the Southern Nevada Water Authority (Appendix B [see PDF docket ID EPA-HQOW-2009-0297-0494]), and MWD data from the Whittsett intake (Appendix C [see PDF docket ID 

EPA-HQ-OW-2009-0297-0494]). This is raw water data from the Colorado River intakes at these 

utilities, which is blended with local water supplies. 

EPA also should take care to recognize in its population exposure estimates the differences between 

perchlorate in ground water and surface water. Many groundwater systems do not run all of the 

system's wells continuously. Wells with higher concentrations of perchlorate may be blended with 

lower concentrations, causing a diluting effect. Concentration of surface water sources may change 

due to precipitation. These factors could cause EPA's estimates to be more conservative than stated 

in the NODA. 

It is important for EPA to properly characterize its estimates of the potential population exposed to 

perchlorate. AMWA recognizes that these estimates include ranges, but the best data available must 

be used so that these estimates are as thoughtful and accurate as possible. Overestimating the 

populations affected would effectively lead to an overestimation of the benefits. Overestimating 

populations affected by perchlorate exposure in drinking water could also effectively build a basis 

for a body of literature that mischaracterizes the situation, which could then be perpetuated and 

misused as the information is referenced in the future. 

Response: EPA acknowledges that there may be sources that had detected perchlorate from 

UCMR1 monitoring that are either no longer being used or are being treated per the requirements of 

maximum contaminant levels established in California and Massachusetts; however, the 1996 

amendments to the Safe Drinking Water Act require the Agency to consider the best available, peer 

reviewed science when developing drinking water standards. In applying these principles, "best 

available" usually refers to the availability at the time an assessment is made. UCMR data is the most 

extensive nationally representative occurrence data for perchlorate in public water systems; 

therefore, EPA analyzed this data and additional occurrence data in making a regulatory 

determination for perchlorate. 

EPA agrees that it is important to properly characterize the estimates of potential population 

exposed to perchlorate. Please see response to comment ID 28810 in comment code 3170. 
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Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28838 

EPA Comment Code: 3200 

Comment: With regard to using data from the Commonwealth of Massachusetts to help 

characterize the distribution of very low perchlorate concentration occurrence, AMWA is concerned 

about extrapolating these data to determine a nationwide distribution for two reasons. First, 89% of 

public water systems in Massachusetts are solely groundwater systems. In addition, a large number 

of these systems are non-community water systems. Secondly, the mechanics of perchlorate 

persistence and occurrence in ground water across the country differ due to factors such as soil 

retention, subsurface geology, etc. 

Therefore, AMWA recommends that EPA extrapolate this data nationwide only for systems that use 

groundwater, taking care to recognize the proportion of Massachusetts data that are community 

water systems vs. non-community water systems as well as the differences in other factors that 

would likely affect these numbers. 

Response: EPA did not extrapolate data from Massachusetts nationwide to aid in the determination 

of a regulation for perchlorate. EPA did analyze the best available and most extensive nationally 

representative occurrence data from UCMR along with additional occurrence data, and concluded 

that regulation of perchlorate was warranted. The Agency evaluated supplemental drinking water 

monitoring data for perchlorate from California and Massachusetts, and believes that these States’ 

monitoring results are generally consistent with the results EPA collected under the UCMR 1. 
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EPA Comment Code: 3300 Other drinking water occurrence studies, models, 

and data for EPA to consider (besides UCMR 1 and California and 

Massachusetts data already evaluated) 

Response to Code 3300: Thank you for providing additional data on the occurrence of perchlorate. 

In August 2009, the Agency sought comments on additional approaches to analyzing data related to 

EPA's perchlorate regulatory determination. These additional comments were sought in an effort to 

ensure consideration of all the potential options for evaluating whether there is a meaningful 

opportunity for health risk reduction of perchlorate through a national primary drinking water rule. 

EPA evaluated the additional occurrence data received and has considered it along with the UCMR 

1 data, which is currently the best available and most extensive nationally representative monitoring 

program for perchlorate in public water systems. 

Using the criteria mandated by the 1996 SDWA Amendments, EPA has determined that regulation 

of perchlorate in drinking water systems presents a meaningful opportunity to reduce health risk for 

persons served by public water systems. See response to comment code 6120. 

Individual Comments 

Commenter Name: Douglas, J. Feldman, PE 

Commenter Organization: Office of Water Resources, Suffolk County Department of Health 

Services (SCDHS) 

EPA Document ID: EPA-HQ-OW-2008-0692-0297 

EPA Comment ID: 19753 

EPA Comment Code: 3300 

Comment: The Suffolk County Department of Health Services (SCDHS), located within the 

County of Suffolk, in New York State, has conducted a search of our records for the past 10 years as 

it relates to sampling for the chemical perchlorate. The Department has found that of the 5882 

samples obtained for perchlorate analyses, between 1998 and 2008, approximately 420 samples were 

found to contain perchlorate with concentrations that ranged between 1ppb and 49 ppb - with the 

mean value of 7.17 ppb. This data indicates that approximately 7% of these samples that were 

checked for perchlorate contained the chemical. It should be noted that of the 420 samples that 

were positive, 18 were found in community water supply distribution systems; 49 were found in 

non-community public water supply wells, and 351 were obtained from private wells. 

The Long Island aquifer has been designated as "sole source" by the USEPA and is particularly 

sensitive to perchlorate discharges, due in part to the sand and gravel material that exist above and 

within our aquifer systems. The Department has been involved with determining and remediating 

the sources of perchlorate plumes impacting public and private wells within our County. An 

extensive amount of time, effort and cost was expended by the Department in performing these 

tasks. 

Response: Please see the response to comment code 3300. 

Commenter Name: Marcia Willhite 

Commenter Organization: Illinois Environmental Protection Agency 
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EPA Document ID: EPA-HQ-OW-2007-0068-0155 

EPA Comment ID: 20258 

EPA Comment Code: 3300 

Comment: The Illinois EPA has detected and confirmed the presence of these contaminants in soil 

and potable resource groundwater. Perchlorate has been found at: Crab Orchard National Wildlife 

Refuge (1,200 micrograms per liter ("μg/l")), Savanna Army Depot (1.2 to 12 μg/l), and Chanute Air 

Force Base (2.9 μg/l). In addition, there are several other potential sites where it is suspected that 

perchlorate will be found, but the groundwater has not been tested for perchlorate. 

Response: Please see the response to comment code 3300. 

Commenter Name: Kathy M. Kinsey 

Commenter Organization: Maryland Department of the Environment 

EPA Document ID: EPA-HQ-OW-2008-0692-1421 

EPA Comment ID: 20427 

EPA Comment Code: 3300 

Comment: A Uniform Federal Drinking Water Standard is Necessary to Protect Public Health 

On the merits of EPA's preliminary determination, based on an initial review, the Department 

submits that perchlorate is present in ground and surface drinking water at levels of public concern 

and that establishment of a drinking water standard presents a meaningful opportunity to reduce the 

health risk perchlorate presents, particularly to the vulnerable and sensitive subpopulations - 

pregnant and lactating women, fetuses, and young children. There are no technological impediments 

to removing perchlorate from ground or surface water. Technology capable of removing perchlorate 

from ground and surface water is already in use. For larger surface water systems eliminating or 

reducing the source of the contamination would likely be the most practical solution. 

Section 1412(b)(1)(A) of the Safe Drinking Water Act requires EPA to establish a maximum 

contaminant level for a contaminant if: (1) the contaminant may have an adverse effect on the health 

of persons; (2) the contaminant occurs or presents a substantial likelihood that it will occur in public 

water systems at a frequency and at levels of public concern; and (3) EPA determines that regulation 

of the contaminant presents a meaningful opportunity for health risk reduction for persons served 

by public drinking water supplies. In the case of perchlorate, each of the criteria is satisfied. 

There is no genuine dispute that perchlorate may have an adverse effect on human health. 

Perchlorate is known to interfere with thyroid function. Lower thyroid hormone levels can cause 

changes that adversely impact brain development. In its preliminary determination, EPA 

acknowledges that at sufficiently high doses, perchlorate can interfere with thyroid function in 

pregnant women, fetuses, newborns and young children. 

In Maryland, perchlorate is present at significant levels in ground and surface water at three 

Department of Defense facilities. At Aberdeen Proving Ground in Harford County, Maryland, 

perchlorate has been detected in groundwater at seven different locations and at levels as high as 350 

parts per billion ("ppb"). Perchlorate from other areas of the installation has contaminated the water 

supply for the City of Aberdeen. In the absence of a federal drinking water standard, the State has 

set an advisory level of 1 ppb for the City treatment system's finished water. 
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Although no public drinking water supply wells have been impacted, perchlorate levels in ground 

water at the Naval Support Facility at Indian Head have been detected at levels as high as 2,900 ppb. 

At a number of other sites in Cecil County, Maryland, perchlorate contamination was detected in 

ground water monitoring wells at levels as high as 230,000 ppb in the late 1990's. In the one case 

where perchlorate contamination has impacted the drinking water supply, the Department has 

provided bottled water to affected residents and required installation of a treatment system to 

address the contamination. Perchlorate contamination has also been detected in the Potomac River, 

the source of drinking water for millions of Maryland, Virginia, West Virginia and District of 

Columbia residents. EPA sampling detected perchlorate levels up to 8 ppb in one of Maryland's 

Potomac River water supply intakes. 

Establishing a federal drinking water standard that would protect the millions of people, including 

pregnant women, infants and young children, who are served by drinking water that is currently 

contaminated or at risk of contamination by perchlorate is necessary to protect public health. 

Response: EPA agrees with the commenter that the three criteria for determining whether a 

contaminant should be regulated from SDWA section 1412(b)(1) are satisfied for perchlorate. Please 

see the responses to comment codes 6120 and 3300. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association 

EPA Document ID: EPA-HQ-OW-2008-0692-1424 

EPA Comment ID: 20438 

EPA Comment Code: 3300 

Comment: Occurrence 

As noted above, one of the criteria for evaluating the need for potential regulatory actionis 

occurrence. In 2005, AWWA prepared an assessment of data collected under the first Unregulated 

Contaminant Monitoring Rule (UCMR1). AWWA recently completed a follow-up of this initial 

assessment using the final UCMR1 data set considered by EPA in this proposed decision. There 

were very subtle differences, in total numbers, but that did not result in a significant difference in the 

overall findings. This analysis is summarized below and has been submitted to a peer-reviewed 

journal and is pending publication. 

The evaluation by Brandhuber et.al. (pending publication) consolidated existing potable water 

perchlorate occurrence information taken from UCMR1 and other recently completed occurrence 

studies. The detection of perchlorate in drinking water was determined to be geographically 

widespread but at very low concentrations. Significantly, there was little correlation between 

perchlorate detection in drinking water and known points of perchlorate release to the environment 

identified by the USEPA. Perchlorate has been detected in drinking water in at least 26 States and 

Puerto Rico and in approximately 5% of the nation's large community water systems (>10,000 

population served). When detected, perchlorate was typically present at concentrations of less than 

12 ug/L and was generally found in less than one half of the sources for systems which sampled 

multiple sources. No statistically significant difference in the rate of perchlorate occurrence between 

surface and ground waters was identified. 
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Extrapolating the results of the occurrence studies reviewed by this report, it appears that nationally 

less than 1% of all drinking water systems would be impacted if an MCL of 20ug/L were 

established. An MCL of 2 ug/L could impact approximately 4% of public water systems nationally. 

At this level, regional impacts in California and Texas would be greater due to the higher 

geographical concentration of detections in those states. Yet it should be noted that water systems in 

Massachusetts, New Jersey and California have already established regulatory limits of 2 ug/L, 5 

ug/L and 6 ug/L respectively, thereby capping the population exposure potential from community 

drinking water sources in those states. 

The estimated population exposure calculated from UCMR1 findings has also been greatly reduced 

by the effectiveness of mitigating contamination sources on the Colorado River to levels below 2 

ug/L. This reduction in levels in the Colorado River alone represents a reduction in the exposure 

potential of approximately 20 million persons in several western states, primarily California and 

Arizona. In addition, a recent telephone survey of water systems detecting perchlorate indicated that 

at least 50 MGD of water production has been taken off line nationally due to the presence of 

perchlorate since UCMR1 monitoring was completed. 

Response: Thank you for providing the additional analysis of data on the occurrence of 

perchlorate. EPA notes that New Jersey proposed an MCL of 5 μg/L in April 2009, but this 

standard has not been finalized. In July 2006, Massachusetts set an Maximum Contaminant Level 

(MCL) of 2 μg/L. Additionally, In October 2007, California set an MCL of 6 μg/L. Please see 

response to comment ID 28755 in comment code 3300. Using the criteria mandated by the 1996 

SDWA Amendments, EPA has determined that regulation of perchlorate in drinking water systems 

presents a meaningful opportunity to reduce health risk for persons served by public water systems. 

See response to comment code 6120. 

Commenter Name: Paul J., P.E. Ponturo 

Commenter Organization: Long Island Water Conference 

EPA Document ID: EPA-HQ-OW-2008-0692-1260 

EPA Comment ID: 20622 

EPA Comment Code: 3300 

Comment: November 7, 2008 

Water Docket Environmental Protection Agency Mailcode 2822 T 1200 Pennsylvania Ave., NW 

Washington, DC 20460 

Re: Docket ID No. EPA-HQ-OW-2008-0692 Drinking Water: Preliminary Regulatory 

Determination on Perchlorate, FR 10/10/08 

Gentlemen: 

On behalf of the Long Island Water Conference, an association of public water supply professionals 

in Nassau and Suffolk Counties in NY, I am pleased to present our comments on the referenced 

preliminary regulatory determination. 

Our member suppliers have a long history of responsiveness in meeting the increasing needs for 

comprehensive water supply monitoring, research and groundwater protection programs. We have 
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worked cooperatively with our regional regulatory agencies to provide monitoring and oversight that 

dramatically exceeds federal EPA requirements. Aggressive monitoring is necessary and desirable in 

protecting public health. We have also worked with regional regulatory agencies in water supply and 

water resource management studies and supported the integration of local regulations which 

combine discharge controls, land use, and the storage of hazardous substances into an advanced 

source water protection system. 

Long Island was one of the first designated Sole Source Aquifer systems in the United States, and 

with a total population of nearly three million, is considered to be one of the most intensively used 

and critical Aquifer systems in the country. 

This preliminary regulatory determination therefore is significant to every public water supplier on 

Long Island. Approximately 250 community water supply wells in Nassau and Suffolk County have 

indicated detection of perchlorate in concentrations greater than 1 ppb. Consistent with EPA's 

occurrence evaluation, a much smaller number of sources exhibit concentrations greater than 5 ppb 

(approximately 25) or 10 ppb (approximately 10). The Health Reference Level (HRL) of 15 ppb 

used by EPA to reach this determination is close to the NYS Department of Health's Action Level 

(discussed below); no Long Island public water supplier customer is being currently exposed to 

concentrations in excess of this Level. 

Response: Please see the response to comment code 3300. 

Commenter Name: Paul J., P.E. Ponturo 

Commenter Organization: Long Island Water Conference 

EPA Document ID: EPA-HQ-OW-2008-0692-1260 

EPA Comment ID: 20623 

EPA Comment Code: 3300 

Comment: We do not have a technical basis upon which to criticize EPA's determination. Based 

upon its interpretation of Safe Drinking Water Act criteria, EPA has determined there is not a 

"meaningful opportunity for health risk reduction" through a national drinking water regulation. 

EPA's conclusion is based upon its own analysis of available data indicating that perchlorate was 

found at levels of public health concern (the HRL) in less than 1 percent of public drinking water 

systems sampled. 

However we do wish to point out that without a greater understanding of perchlorate formation 

processes and the possibility that unmeasured perchlorate may exist in other salts in common use, 

one may still lack statistical confidence in utilization of the UCMR data to estimate population 

exposures in drinking water. Unlike other parts of the country, a clear source for many of Long 

Island's perchlorate contamination occurrences has not emerged over the past 10 years. The highest 

recorded perchlorate concentration in a well on Long Island was traced to a completely unregulated 

activity, as described below. 

Perchlorate monitoring of public water supplies on Long Island began in the spring of 1998. Initially 

in response to perchlorate detection reports elsewhere in the US, the Suffolk County Water 

Authority (SCWA) voluntarily collected samples from wells at five wellfields. The samples were sent 

to the Montgomery Watson Laboratory for analysis. Of the initial sample results one well - #3 at the 

Old Country Road wellfield in Westhampton - indicated a concentration of perchlorate of 30 ppb. 
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The SCWA removed this well from service. At the end of 1998, NY State Department of Health 

provided an Action Level of 18 ppb. This well later showed concentrations as high as 127 ppb in 

samples collected during subsequent test pumping. Initial thoughts were directed to the former 

military uses of property immediately upgradient of the well at a former BOMARC missile site. This 

was discounted, upon submission of evidence that solid fuel rockets were not deployed at this site. 

By late 1998, attention turned to a review of more recent activities subsequent to the takeover of the 

BOMARC site by Suffolk County - specifically the Suffolk County Police Department (SCPD) 

practice of disposal of confiscated fireworks and munitions by burning. Between November 1998 

and February 2000, a total of 18 profile wells were installed by the Suffolk County Department of 

Health Services' (SCDHS) Bureau of Groundwater Resources in locations upgradient and 

downgradient of the fireworks disposal pit, which was located in the northwest corner of the site. 

Groundwater flow direction and water quality data appeared to eliminate other activities in the area 

as potential sources. Perchlorate was detected in 9 test wells downgradient of the pit, in 

concentrations as high as 3,370 ppb. Although the pit and burning practices have been modified, 

fireworks disposal at the site continues, and to date such disposal is not covered under any NY State 

environmental regulation. In subsequent years, SCDHS also investigated the contamination of a 

number of private wells and one non- communitysupply well in Yaphank, NY, which later traced to 

fireworks testing and a practice of stabilizing "dud" fireworks by a process called "soaking." This 

process utilizes water indrums to leach out the perchlorate from the dud, stabilizing the firework for 

subsequent disposal by burning. 

Local laboratory capacity has been developed at SCWA, SCDHS and at private labs to assist in the 

monitoring effort, which began in earnest before the UCMR implementation date, and monitoring 

continues. 

Response: Please see response to comment code 3300. 

Commenter Name: Mic Stewart 

Commenter Organization: Metropolitan Water District of Southern California 

EPA Document ID: EPA-HQ-OW-2008-0692-1784 

EPA Comment ID: 20661 

EPA Comment Code: 3300 

Comment: November 6, 2008 

Attention: Docket ID Number EPA-HQ-OW-2008-0692 OSWER Docket EPA Docket Center 

Mailcode: 2822T Environmental Protection Agency 1200 Pennsylvania Ave., NW Washington, DC 

20460 

Dear Environmental Protection Agency: 

The Metropolitan Water District of Southern California (Metropolitan) is submitting comments on 

U.S. Environmental Protection Agency's (EPA's) Preliminary Regulatory Determination on 

Perchlorate (73 Federal Register 60262). The proposed action by the EPA not to regulate the 

drinking water contaminant perchlorate will affect how state and local officials can respond to 

localized perchlorate contamination. 
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Metropolitan is a regional water supply agency that provides supplemental water to nearly 19 million 

people throughout the southern California area. Our major source of supply, the Colorado River, 

was contaminated from industrial production of perchlorate for solid rocket fuel and subsequent 

improper disposal methods. Perchlorate contaminated groundwater seeping into Lake Mead through 

the Las Vegas Wash area found its way into the Colorado River, which supplies Metropolitan and 

other downstream users. Levels as high as 20 parts per billion (ppb) were detected in Lake Mead and 

levels as high as 9 ppb have been detected at the intake to Metropolitan's conveyance system. 

Following the detection of perchlorate in the Colorado River, Metropolitan along with the EPA and 

regulatory agencies in Nevada, organized the forces necessary to successfully treat and decrease the 

sources of perchlorate loading. Since 2006, monitoring has indicated levels at or below 2 ppb 

entering Metropolitan's conveyance system. 

Response: Please see the response to comment code 3300. 

Commenter Name: Stephen A. Owens 

Commenter Organization: Arizona Department of Environmental Quality 

EPA Document ID: EPA-HQ-OW-2008-0692-1785 

EPA Comment ID: 20665 

EPA Comment Code: 3300 

Comment: November 7, 2008 

Comment Clerk Water Docket Environmental Protection Agency Mail Code: 2822T 1200 

Pennsylvania Ave., NW. Washington, DC 20460 

Re: Arizona Department of Environmental Quality Comments on Federal Preliminary Regulatory 

Determination on Perchlorate Docket EPA-HQ-OW-2008-0692 

Dear Sir: 

In response to the notice in the Federal Register of October 10, 2008 (Volume 73, Number 198) the 

Arizona Department of Environmental Quality (ADEQ) is offering comments on the Preliminary 

Regulatory Determination on Perchlorate. ADEQ offers these comments in role of the delegated 

authority responsible for protecting public health in Arizona through rules promulgated under the 

Federal Safe Drinking Water Act. 

Perchlorate contamination is known to be present in Arizona water supplies. Arizona, along with 

other arid western states, relies heavily upon the Colorado River as a critical source of our 

population's drinking water supply. The overall "health" and water quality of the Colorado River and 

other surface water sources are of the utmost concern for Arizona. Perchlorate contamination has 

impacted the Colorado River due to industrial sources in the Las Vegas area. The source of this 

contamination has been controlled more effectively by the responsible parties; however the risk of 

perchlorate contamination in the Colorado River water supply still exists. 

A Consumer Confidence Report issued by the City of Phoenix (City) in 2007 is one example of a 

direct perchlorate related impact on Arizona citizens. According to City records, roughly ninetyeight 

percent of all potable water produce annually is derived from surface sources, including water from 

the Colorado River. In 2004, the City collected 392 finished water distribution samples (as a 
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precautionary measure) to gather more information on the occurrence of perchlorate in the public 

water system supply. Thirty-nine of those samples tested at, or above, the minimum detection level 

of four (4) part per billion for the presence of perchlorate. 

Perchlorate contamination is not strictly limited to surface waters of the Southwest. A perchlorate 

occurrence study conducted by ADEQ (Perchlorate in Arizona: Occurrence Study of 2004) revealed 

numerous groundwater sources with detectable levels of perchlorate. One well located in Yuma 

County tested positive in 2004 for levels of perchlorate in the 15 parts per billion (ppb) range. 

Groundwater is a critical source of drinking water in Arizona and under Arizona law all aquifers in 

the state are designated by statute for drinking water use. 

Response: Please see the response to comment code 3300. 

Commenter Name: Ron Curry 

Commenter Organization: New Mexico Environment Department 

EPA Document ID: EPA-HQ-OW-2008-0692-1796 

EPA Comment ID: 20933 

EPA Comment Code: 3300 

Comment: Nevertheless, the limited available drinking water data that the Environment 

Department has reviewed show significant perchlorate contamination in several public drinking 

water systems around the State. In the Department's view, perchlorate contamination in drinking 

water occurs at levels and at a frequency that is a public health concern in New Mexico.[FN2: See 

SDWA [section] 1412(b) (1)(A)(ii), 42 U.S.C. [section] 300g-1(b)(1)(A)(ii) (Westlaw 2008).] 

At Cannon Air Force Base, near Clovis, New Mexico, the Environment Department received data in 

1999 showing perchlorate concentrations of 46 micrograms per liter (ug/L) in production well PW-2 

and 21 ug/L in production well PW-7. These wells are both active drinking water production wells 

that serve users on the Base.[FN3: N.M. Environment. Dep't, Perchlorate Survey 2001 Final Report, 

vol. 1, tab "Cannon" (unpublished compilation).] Data that the Environment Department gathered 

in 2001 from Cannon showed perchlorate contamination of 23.5 ug/L in PW-12, another drinking 

water production well.[FN4: Id.] Data collected from the system in 2003 and submitted to the 

Environment Department under the Unregulated Contaminant Monitoring Ruleshows a perchlorate 

level at 30 ug/L.[FN5: Safe Drinking Water Information System, State version (SDWIS/State). The 

State has not verified the accuracy of this data.] In addition, the Government Accountability Office 

(GAO) has compiled data on perchlorate contamination throughout the United States, including 

New Mexico. In its 2005 report, GAO similarly reported perchlorate at 46 ug/L in drinking water at 

Cannon Air Force Base.[FN6: GOVERNMENT ACCOUNTABILITY OFFICE, A SYSTEM TO 

TRACK SAMPLING AND CLEANUP RESULTS IS NEEDED, AT 37 (GAO-05-462) (May 

2005).] 

At the Melrose Bombing Range, also near Clovis, the Environment Department received data in 

1999 showing perchlorate contamination in production well PW-11, an active drinking water 

production well for the facility, at 25 ug/L.[FN7: N.M. Environment. Dep't, Perchlorate Survey 

2001 Final Report, vol. 2, tab "Melrose" (unpublished compilation).] Data the Environment 

Department obtained in 2001 from Melrose showed perchlorate concentrations of 30.3 ug/L and 

40.7 ug/L in PW-11(shown as MAFR Well-11), and a perchlorate concentration of 5.52 ug/L in 

PW-13 (shown as MAFR Well-13), an other on-site facility drinking water supply wel1.[FN8: Id.] 
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At Kirtland Air Force Base, data collected in 2004 show perchlorate contamination in Well #17, a 

drinking water supply well, at 12.6 ug/L.[FN9: Letter from Carl J. Lanz, Chief, Restoration Section, 

Kirtland Air Force Base, to Sandra Martin, Chief, Hazardous Waste Bureau, N.M. Environment 

Dep't (Mar. 31, 2004).] Kirtland is located adjacent to the City of Albuquerque, which is the State's 

largest metropolitan area having a population over 500,000. Yet there is very little available data on 

perchlorate in drinking water on and around Kirtland. 

The GAO also reported perchlorate contamination in the municipal drinking water supply for the 

City of Deming, New Mexico at 20 ug/L, and for the City of Des Moines, New Mexico at 5 ug/L. 

GAO reported perchlorate in the drinking water supply for the City of Clovis, New Mexico, 

operated by the American Water Company, at 7 ug/L. GAO also reported perchlorate in the water 

supply for the community of Mountain View Albuquerque, in the South Valley of Albuquerque, 

New Mexico, at 5 ug/L. 

The Environment Department has gathered additional data demonstrating widespread perchlorate 

contamination in groundwater at several military installations and nuclear weapons facilities 

throughout the State. In many cases, this contamination threatens present and future drinking water 

supplies. 

At Los Alamos National Laboratory, perchlorate contamination has been monitored in groundwater 

beneath much of the 40-square mile facility. Of particular significance, sampling conducted 

beginning in 2005 shows perchlorate concentrations ranging between 30 ug/L and 256 ug/L in 

intermediate wells located in Mortandad Canyon. More recent data shows that this contamination 

has remained relatively constant. A deeper monitoring well, Well R-15, shows a perchlorate 

concentration of 7 ug/L. The highest contamination, 256 ug/L in intermediate well MCOBT-4.4, is 

within 2000 feet from PM-5, a municipal drinking water production well for Los Alamos County. 

Low concentrations of perchlorate, below 1 ug/L, have been detected in PM-5. Neither the sources 

of the perchlorate contamination, nor the nature and extent of the perchlorate plume, are fully 

characterized. The perchlorate contamination threatens the Los Alamos County water supply, which 

serves approximately 20,000 people. 

At Sandia National Laboratories, adjacent to the City of Albuquerque, perchlorate has been found in 

the EOD Hill monitoring well at concentrations ranging from 680 ug/L to 4300 ug/L. Data from 

2006 and 2007 show that perchlorate has been detected in CYN-MW6 monitoring well at 

concentrations between 6.56 ug/L and 8.93 ug/L. Perchlorate data at Sandia is limited, however. 

At the United States Army White Sands Missile Range, near Socorro, New Mexico, high levels of 

perchlorate contamination in soil and groundwater is widespread. In 2000, perchlorate was detected 

in 22 of 23 groundwater monitoring wells at concentrations ranging from 5 ug/L to 21,000 

ug/L.[FN10: N.M. Environment. Dep't, Perchlorate Survey 2001 Final Report, vol. 2, tab "White 

Sands" (unpublished compilation).] Currently, the highest concentrations are 19,000 ug/L. The 

Army has vigorously resisted conducting any corrective action to remedy the contamination. 

At Holloman Air Force Base, groundwater data collected in September 1999 showed perchlorate 

levels of 15.5 ug/L in monitoring well NM-39-02-01, 15.2 ug/L in monitoring well NM-39-02-02, 

and 38.9 ug/L in monitoring well NM-39-03. 
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At Kirtland Air Force Base, data collected in 2006 showed perchlorate levels in monitoring well 

KAFB-2622 at 8.4 ug/L, and in monitoring well KAFB-2624 at 11.0 ug/L. Data collected in 2008 

showed perchlorate in the "School House Mesa Well" at 5.19 ug/L. Yet very little groundwater 

monitoring data has been obtained for perchlorate at Kirtland. 

Response: Please see response to comment code 3300. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-2082 

EPA Comment ID: 21026 

EPA Comment Code: 3300 

Comment: 9. Your letter asserts that in the absence of a federal MCL, high perchlorate levels in 

drinking water will go undetected and therefore national monitoring is needed. 

The use of Unregulated Contaminant Monitoring Rule (UCMR) sampling data for regulatory 

determinations is well established. The nationally- representative UCMR 1 results show that 

perchlorate does not occur frequently or at levels of public health concern in public water systems. 

Additionally, as evidenced by more recent sampling results from Lake Mead, the Las Vegas Wash, 

and the Metropolitan Water District of Southern California (MWD), perchlorate levels continue to 

decline since the time of the UCMR 1 sampling. The preliminary determination assumes that the 

concentrations measured in the UCMR 1 survey are still occurring. In fact, levels in many of the 

highest reported drinking water systems have significantly declined due to source control. 

Response: Please see the response to comment ID 28755 in comment code 3300. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21095 

EPA Comment Code: 3300 

Comment: Additionally, as evidenced by sampling results from Lake Mead, the Las Vegas Wash, 

and the Metropolitan Water District of Southern California, perchlorate levels continue to decline 

since the time of the UCMR 1 sampling. The preliminary determination assumes that the 

concentrations measured in the UCMR 1 survey are still occurring. In fact, levels in many of the 

highest reported drinking water systems have significantly declined due to source control. 

Response: Please see the response to comment ID 28755 in comment code 3300. 

Commenter Name: James D. Taft 

Commenter Organization: Association of State Drinking Water Administrators 

EPA Document ID: EPA-HQ-OW-2009-0297-0525 

EPA Comment ID: 28499 

EPA Comment Code: 3300 
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Comment: Comments on interpreting occurrence data - Because many states do not have 

significant occurrence of perchlorate and some had no occurrence, states are concerned that the 

burden of a possible rule would fall heavily on these states and their water systems with little actual 

reduction in health risk for their water consumers. ASDWA is also familiar with new data from 

Nevada (submitted separately) that indicate a reduction in perchlorate levels since the UCMR data 

were collected. These data need to be included in the analyses along with the modeling approach and 

use of census data that are addressed in the specific questions. 

Response: EPA acknowledges the commenters concern for a federal perchlorate regulation and 

that some states had no occurrence during UCMR1 monitoring; EPA analyzed additional 

occurrence data received along with UCMR data (which is the best available and most extensive 

nationally representative occurrence database for perchlorate in public water systems known to date) 

and using the criteria mandated by the 1996 SDWA Amendments, determined that regulation of 

perchlorate in drinking water systems presents a meaningful opportunity to reduce health risk for 

persons served by public water systems. See response to comment code 6120. When EPA proposes 

a NPDWR that includes a maximum contaminant level, EPA will analyze and consider both the 

costs and benefits that would result from regulation and present these analyses for public comment. 

See SDWA section 1412(b)(3)(C). 

Commenter Name: Mic Stewart 

Commenter Organization: Water Quality Section, Metropolitan Water District of Southern 

California 

EPA Document ID: EPA-HQ-OW-2009-0297-0496 

EPA Comment ID: 28709 

EPA Comment Code: 3300 

Comment: September 18, 2009 Attention: Docket ID Number EPA HQ-OW-2009-0297 EPA 

Docket Center Mailcode: 2822T Environmental Protection Agency 1200 Pennsylvania Ave., NW 

Washington, DC 20460 

Dear Environmental Protection Agency: 

The Metropolitan Water District of Southern California (Metropolitan) is submitting comments on 

U.S. Environmental Protection Agency's (EPA) Drinking Water: Perchlorate Supplemental Request 

for Comments (74 Federal Register 41883). This EPA notice follows the previously proposed action 

by the EPA not to regulate the drinking water contaminant perchlorate which will affect how state 

and local officials can respond to localized perchlorate contamination. 

Background on the Southern California Situation 

Metropolitan is a regional water supply agency that provides supplemental water to nearly 19 million 

people throughout the southern California area. Our major source of supply, the Colorado River, 

suffered significant contamination from industrial production of perchlorate for solid rocket fuel 

and subsequent improper disposal methods. Perchlorate-contaminated groundwater seeping into 

Lake Mead through the Las Vegas Wash found its way into the Colorado River, which supplies 

southern California and other downstream users. Levels as high as 20 parts per billion (ppb) were 

detected in Lake Mead and levels as high as 9 ppb have been detected at the intake to Metropolitan's 

conveyance system, located approximately 160 miles south of the Las Vegas Wash. 
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In 1997, the source of perchlorate contamination in the Colorado River was traced to a chemical 

manufacturing facility formerly owned by Kerr-McGee Corp., and now owned by Tronox, Inc. 

Tronox, previously a chemical subsidiary of Kerr- McGee, has assumed the responsibility of the 

ongoing perchlorate remediation activities in Henderson, Nevada. Another large perchlorate 

groundwater plume is also present in the Henderson area from a second industrial site, and although 

not known to have reached Las Vegas Wash yet, remediation activities are ongoing for cleanup of 

that plume by American Pacific Corporation. 

Following the detection of perchlorate in the Colorado River, Metropolitan, along with the EPA and 

agencies in Nevada including the Nevada Division of Environmental Protection (NDEP), organized 

the forces necessary to successfully treat and decrease the sources of perchlorate loading. Under 

NDEP oversight, remediation efforts began in 1998 and the treatment operations became fully 

operational in 2004. These efforts have reduced perchlorate loading into Las Vegas Wash from over 

1,000 lbs/day (prior to treatment) to 60-90 lbs/day since early 2007. These have resulted in over 90 

percent reduction of the perchlorate loading entering the Colorado River system. 

Perchlorate levels in Colorado River water at Lake Havasu have decreased significantly in recent 

years from a peak of 9 ppb in May 1998 as a result of aggressive clean-up efforts at Henderson, 

Nevada (see Figure 1). Levels have remained less than 6 ppb since October 2002, and have been 

generally less than 2 ppb since June 2006. 

Figure 1. Declining Perchlorate Levels at Lake Havasu [see PDF docket ID EPA- HQ-OW-2009-

0297-0496] 

Response: Please see response to comment code 3300. 

Commenter Name: Mic Stewart 

Commenter Organization: Water Quality Section, Metropolitan Water District of Southern 

California 

EPA Document ID: EPA-HQ-OW-2009-0297-0496 

EPA Comment ID: 28711 

EPA Comment Code: 3300 

Comment: On January 12, 2009, Tronox filed for Chapter 11 bankruptcy protection (U.S. 

Bankruptcy Court, Southern District of New York). The company cited the significant 

environmental liabilities taken on from Kerr-McGee as a primary cause of its financial liabilities. 

Tronox has indicated plans to restructure the company while continuing its operations. Metropolitan 

is concerned that the outcome of the bankruptcy proceedings could potentially impede or even 

reverse the ongoing cleanup efforts aimed at remediating perchlorate contamination entering the 

Colorado River. If perchlorate treatment in the Las Vegas Wash area were discontinued, modeling 

results suggest that perchlorate levels in the Colorado River could spike to concentrations as high as 

9 ppb in as little as 18 months. This level of perchlorate would result in non-compliance by drinking 

water utilities with California's existing MCL for perchlorate of 6 ppb. 

While the State of California does have a 6 ppb MCL for perchlorate, this drinking water standard is 

not enforceable outside the State. EPA's role in establishing and enforcing a national drinking water 

standard for perchlorate will be critical in the long-term remediation of perchlorate contamination in 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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the Colorado River and hundreds of U.S. Department of Defense sites around the country. Since 

the detection of perchlorate contamination throughout the southwest region and in hundreds of 

local groundwater wells, Metropolitan, its member agencies, and the drinking water community have 

called on the EPA to make a regulatory determination on perchlorate consistent with the tenets of 

the Safe Drinking Water Act. Metropolitan believes that the unique factors surrounding regional 

perchlorate contamination in the Colorado River system need to be considered. 

Response: The commenters concerns regarding the outcome of the bankruptcy proceedings are 

outside of the scope of this action. Regarding your comment that EPA "make a regulatory 

determination on perchlorate consistent with tenents of the Safe Drinking Water Act," using the 

criteria mandated by the 1996 SDWA Amendments, EPA has determined that regulation of 

perchlorate in drinking water systems presents a meaningful opportunity to reduce health risk for 

persons served by public water systems. See response to comment code 6120. 

Commenter Name: Mic Stewart 

Commenter Organization: Water Quality Section, Metropolitan Water District of Southern 

California 

EPA Document ID: EPA-HQ-OW-2009-0297-0496 

EPA Comment ID: 28713 

EPA Comment Code: 3300 

Comment: Additionally, Metropolitan would like to suggest that EPA take the additional time 

necessary to review and quantify occurrence data collected by the Agency and by individual states 

including California to better represent possible exposure and occurrence. Perchlorate occurrence is 

expected to increase unlike other contaminants on the Contaminant Candidate List such as 

pesticides that are no longer in use. 

Response: Please see the response to comment code 3300. 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 28755 

EPA Comment Code: 3300 

Comment: The Lower Colorado River System provides drinking water to approximately 26 million 

residents of Nevada. Arizona, and California through three primary diversions: 

1) Southern Nevada Water Authority (SNWA) and Black Mountain Inc. Intakes in Lake Mead, 

which serve approximately 2 million residents within the Las Vegas Valley (distributed through 

portions of the City of Las Vegas, the City of Henderson, and Clark County); 

2) The Central Arizona Project (CAP) canal, which conveys water from Lake Havasu (near Parker 

Dam) to several locations throughout Arizona including the Phoenix and Tucson Valleys and serves 

approximately 5 million residents of Arizona; and 

3) The Colorado River Aqueduct operated by the Metropolitan Water District (MWD) of Southern 

California to convey water from Lake Havasu (near Parker Dam) to several communities in southern 
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California including several within the greater Los Angeles area and the greater San Diego area. We 

understand that MWD serves approximately 19 million end users through various wholesale and 

retail agreements. We also understand that water quality measurements collected and posted by 

MWD for the Colorado River Aqueduct are tracked under "Whitsett Intake". 

Additionally, the Colorado River System also is used for irrigating much of the nation's vegetable 

crops grown in the Imperial Valley of California and the Yuma, Arizona area. This water is conveyed 

through the All American Canal from a diversion near Yuma, Arizona to numerous locations in 

southern California near the US / Mexico International border. 

Remediation of perchlorate source areas within the Las Vegas Valley has substantially reduced (by 

approximately 90 %) the amount of perchlorate entering the Colorado River System (NDEP, 

2009c). Corresponding water quality improvements have been realized along the entire southern 

reach of the Colorado River extending from Lake Mead, though Lake Mohave and Lake Havasu, to 

the US/Mexico International border. Data collected by numerous entities (i.e., NDEP, SNWA, 

MWD, CAP, EPA, and others) since approximately 1997/1999 though current have documented 

the improvements in water quality throughout the lower Colorado River System. The reductions in 

perchlorate entering the Colorado River System can be observed in the graphs of perchlorate data 

provided in Appendix A [See PDF docket ID EPA-HQ-OW-2009-0297-0639] and Appendix B [See 

PDF docket ID EPA- HQ-OW-2009-0297-0640] and are attributable to several successive 

remediation events including (NDEP, 2009d; NDEP, 2009c): 

* initial Seep capture by Kerr McGee (now Tronox) in 1999; * construction of a slurry wall and 

extraction well field in 2001; * operation a full-scale groundwater treatment system in 2002; * 

expansion of the Seep area extraction well field in 2003; * transition from an ion exchange system to 

Fluidized Bed Reactor (FBR) treatment system in 2004; * continued operation and optimization of 

the FBR and well fields from 2005 through current; * initial installation of an In-situ Bioremediation 

(ISB) system by AMPAC in 2005; * initial start-up and operation of the ISB system in 2006; and * 

continued operation and optimization of the ISB system from 2007 through current. 

The referenced reduction in perchlorate mass loading to the Colorado River system (via the Las 

Vegas Wash, a tributary to Lake Mead) were immediately recognized following the initial Seep 

capture and treatment using disposable ion exchange (IX) resin implemented by Kerr McKee 

(Tronox) in late 1999. The mass loading values dropped approximately 40% from approximately 900 

- 1,000 pounds per day to approximately 500 - 600 pounds per day by December 2001 as can be 

seen on the "Perchlorate Loading 12-Month Rolling Average" graph in the NDEP maintained 

Northshore Road data set in Appendix c [See PDF docket ID EPA-HQ- OW-2009-0297-0641] 

(NDEP, 2009b). Continuous reductions in perchlorate mass are seen in the Northshore Road data 

beginning with operation of the full-scale remediation system in October 2002. The decrease in 

perchlorate mass loading continued through conversion to an FBR system in October 2003 and its 

one-year shake-down period. Decreases in perchlorate mass loading have continued from late 2004 

through the present, as Tronox optimized their remediation system and AMPAC initiated 

remediation of a second perchlorate plume in mid 2006 as can be seen on each of the three data 

graphs for the Northshore Road dataset in Appendix A [See PDF docket ID EPA-HQ-OW-2009-

0297-0639] (NDEP, 2009d). Greater than 90% decrease in mass loading has been sustained since 

February 2007 (i.e., for more than two and one half years) as can be seen in the Northshore Road 

tabular data presented in Appendix C [See PDF docket ID EPA-HQ- OW-2009-0297-0641] and the 

related Breakthrough Curve in Appendix D [See PDF docket ID EPA-HQ-OW-2009-0297-0642] 
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(NDEP, 2009b; NDEP, 2009a; McGinley & Associates, 2003). These trends are expected to 

continue. 

Water quality improvements within the Colorado River system are documented within the Southern 

Nevada Water Authority (SNWA) intake data for Lake Mead as can be seen in the Perchlorate 

Monthly Stream Report provided in Appendix E [See PDF docket ID EPA-HQ-OW-2009-0297-

0643] (SNWA, 2009a). Yearly average SNWA Intake data for one of the two existing intakes in Lake 

Mead show a precipitous drop in perchlorate concentrations from approximately 13.4 ug/L in year 

2000, through approximately 10 - 11 ug/L during years 2001, 2002, and 2003, to approximately 2 - 

2.5 ug/L in years 2007, 2008, and 2009 as can be seen in the Perchlorate - Yearly Average - 

AMSWTF Raw Water graph and tabular data provided in Appendix F [See PDF docket ID EPAHQ-OW-2009-0297-0644] (SNWA, 2009b). These water quality improvements correspond to the 

significant reduction in perchlorate mass loading to the Colorado River System via the Las Vegas 

Wash. 

Seasonal water quality fluctuations that are present in the Lake Mead data are a result of seasonal 

lake stratification and mixing events as can be seen in the graph of Saddle Island Intake Data in 

Appendix E [See PDF docket ID EPA-HQ- OW-2009-0297-0643] (SNWA, 2009a). Lake Mead 

typically destratifies annually due to changes in temperature and wind driven mixing. The surface 

waters routinely mix to a depth of 30 - 45 feet below the lake surface level throughout the summer 

(that allows for stratified water quality conditions) and the surface layer deepens to 100 feet in the 

autumn. The lake destratifies in the late winter, resulting in more uniform water quality as 

constituents are dispersed throughout the water column. Therefore, water intake structures 

(including those at Hoover Dam) will be subject to the water quality present within the water 

column adjacent to the intake structure and this water quality will change seasonally. 

Water quality improvements are also noticeable within the NDEP maintained Willow Beach data set 

provided in Appendix G [See PDF docket ID EPA-HQ- OW-2009-0297-0645] (NDEP, 2009c). 

These data were collected from the Arizona side of the Colorado River within Lake Mohave 

approximately 11 miles downstream of Hoover Dam (Lake Mead). It is thought that these data 

represent mixed water quality conditions applicable to downstream users. Review of these data 

shows that perchlorate concentrations have been sustained at less than 4 ug/L, from June 2004 

through current as can be seen on the graph of perchlorate concentration and tabular data provided 

in Appendix G [See PDF docket ID EPA-HQ- OW-2009-0297-0645] (NDEP, 2009c). 

Water quality trends at the Metropolitan Water District (MWD) of Southern California Whitsett 

Intake also show improved water quality over time, with sustained perchlorate concentrations at less 

than 4 ug/L from June 2004 to November 2005 and less than 2.3 ug/L from November 2005 

through present as can be seen in the MWD Whitsett graphical and tabular data provided in 

Appendix H [See PDF docket ID EPA-HQ-OW-2009-0297-0646] (MWD, 2009). These sustained 

declines in perchlorate concentrations led to several actions by MWD including: 

* Lowering of the reporting (detection) limit from 4 ug/L to 2 ug/ L in September 2003; * Change 

in analytical methods to EPA Method 331 in January 2007 and EPA Method 332 in July 2008 to 

permit a 0.1 ug/L reporting limit; and * Change in sample frequency from monthly to quarterly in 

January 2007. [bullets corrected based on docket ID EPA-HQ-OW-2009-0297-0649] 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Similar water quality trends are reported by the Central Arizona Project (CAP) for perchlorate 

concentrations measured in CAP Intake water near Lake Havasu, Arizona. The similar water quality 

results reported from MWD and CAP are a result of both entities drawing source water from the 

same reservoir (Lake Havasu) near Parker Darn, Arizona. 

Response: Thank you for providing additional data on the occurrence of perchlorate. EPA 

acknowledges that there may be sources that had detected perchlorate from UCMR1 monitoring 

that are either no longer being used or are being treated; however, the 1996 amendments to the Safe 

Drinking Water Act require the Agency to consider the best available, peer reviewed science when 

developing drinking water standards. In applying these principles, "best available" usually refers to 

the availability at the time an assessment is made. UCMR data is the most extensive nationally 

representative occurrence data for perchlorate in public water systems; therefore, EPA analyzed this 

data and additional occurrence data in making a regulatory determination for perchlorate. However, 

there will be another opportunity to consider new data during development of a proposed NPDWR 

for perchlorate. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28811 

EPA Comment Code: 3300 

Comment: NRDC Response: Only Massachusetts has finalized a drinking water standard for 

perchlorate; California and New Jersey have not. 

As noted in the Federal Register notice, one commenter incorrectly suggests that the population 

exposed would be capped because of regulatory limits in Massachusetts, California, and New Jersey. 

As a matter of fact, only Massachusetts has promulgated an MCL of 2 ppb for perchlorate in 

drinking water. California has set an unenforceable public health goal of 6 ppb.[FN63: California 

Office of Environmental Health Hazard Assessment, Public Health Goal for Perchlorate. See e.g. 

http://oehha.ca.gov/public_info/facts/Perchloratefacts.html.] New Jersey has proposed, but has 

not finalized, an enforceable standard of 5 ppb.[FN64: New Jersey Department of Environmental 

Protection, New Jersey Register, March 16, 2009 

http://www.state.nj.us/dep//rules/notices/031609a.html] 

Response: In July 2006, Massachusetts set an Maximum Contaminant Level (MCL) of 2 μg/L and 

in October 2007, California set an enforceable MCL of 6 μg/L. New Jersey proposed an MCL of 5 

μg/L in April 2009 but has not finalized it. 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0527 

EPA Comment ID: 28912 

EPA Comment Code: 3300 

Comment: Occurrence Analysis 
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USEPA seeks information on the occurrence of perchlorate at concentrations below the MRL of 4 

ug/L in the Unregulated Contaminant Monitoring Rule (UCMR) studies. In studies conducted by 

NJDEP between 2003 and 2005, subsequent to UCMR sampling, the laboratory was able to achieve 

a MRL of 1 ug/L or lower using EPA Method 314.0. In this study, community and non-community 

public water systems were chosen based on their potential vulnerability to perchlorate 

contamination. Reasons for sampling included proximity to military installations and unexploded 

ordnance, and proximity to previous UCMR-tested sites that showed perchlorate detections; a few 

of the individual public wells that had tested high in the original UCMR sampling were sampled. 

Most, but not all, of these samples were taken before treatment. A small number of these were point 

of entry (POE) samples. Perchlorate was detected in 11 of the 67 public water systems tested at 1 

ug/L or above (NJDWQI, 2005). 

Response: Please see the response to comment code 3300. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group (EWG) 

EPA Document ID: EPA-HQ-OW-2009-0297-0499 

EPA Comment ID: 28934 

EPA Comment Code: 3300 

Comment: In 2005, EWG published findings from a national analysis of tap water contamination 

based on data provided by public water suppliers from seven states, including Texas and California 

(EWG 2005). In our analysis, perchlorate levels above the level of quantification were considered 

significant; we found that over 26 million people in these seven states were served by water systems 

that had at least one perchlorate detection. Since this data was gathered from only seven states, we 

expect that the actual number of people in all 50 states who are served by public water systems with 

at least one perchlorate detection would be much higher. 

EWG recommends that the agency consider any perchlorate detections above the level of 

quantification as significant; this would give a more accurate picture of the number of U.S. residents 

who are actually drinking perchlorate contaminated water. 

Response: Please see response to comment code 5220. Also, see response to comment code 3300. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 4000 Evaluation of Perchlorate Exposure from Sources 

Other than Drinking Water 

Individual Comments 

Commenter Name: Peter King 

Commenter Organization: American Public Works Association (APWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0156 

EPA Comment ID: 20261 

EPA Comment Code: 4000 

Comment: Moreover, APWA supports EPA's assessment that additional investigation is necessary 

to ascertain total human exposure and health risks of perchlorate and MTBE before a preliminary 

determination may be made regarding these chemicals. Finally, we agree that it is important for the 

Agency to try and identify data that can be used to estimate the contribution of perchlorate exposure 

from food versus drinking water and we feel as though the urinary bio-monitoring approach is 

appropriate. 

Response: EPA agrees with the commenter and has refined its urinary biomonitoring approach to 

apportioning perchlorate exposure between food and water. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group (PSG) 

EPA Document ID: EPA-HQ-OW-2007-0068-0168 

EPA Comment ID: 20280 

EPA Comment Code: 4000 

Comment: USE OF ALTERNATIVE APPROACHES WOULD ENABLE EPA TO MAKE A 

DETERMINATION ON PERCHLORATE WITH GREATER SPEED AND SCIENTIFIC 

CERTAINTY 

In its Support Document, EPA presents a number of alternatives for evaluating the third statutory 

criterion, of "meaningful opportunity for health risk reduction" for perchlorate.[FN4: US EPA 

Regulatory Determinations Support Document for CCL2, May 2007 [hereinafter, CCL 2 Support 

Document].] Many of these approaches take advantage of the extensive scientific information 

available on perchlorate. 

EPA outlines several options in its Support Document for using the superior biomonitoring data for 

its regulatory determination. Clearly, real-time human data can be uniquely valuable and would 

enable EPA to make a determination on perchlorate with greater speed and scientific certainty. 

Using such powerful new data, EPA can make a determination more quickly and with more 

scientific certainty than was possible in the past. The National Health and Nutrition Examination 

Survey (NHANES) biomonitoring data provides a more reliable estimate of total perchlorate 

exposure in the US population than the fallback of extrapolating from food data.[FN5: Benjamin C. 

Blount et al., Perchlorate Exposure of the US Population, 2001-2002, J. Expos. Sci. Envtl. 

Epidemiol., Oct. 2006 [hereinafter Blount 2006c].] 
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The biomonitoring data demonstrates that total perchlorate exposure from all sources is below the 

EPA’s health benchmark for virtually all US residents. Since drinking water exposure is a small 

subset of total exposure, it follows that reducing this small subset by a small amount through 

regulation will not meet the meaningful risk reduction criterion of the Safe Drinking Water Act. 

There are two additional approaches that merit Agency consideration, further suggesting that 

drinking water perchlorate levels pose no meaningful risk to human health. One approach posits 

that it is unnecessary for EPA to adjust for total exposure because Greer et al.[FN6: Monte A. Greer 

et al., Health Effect Assessment for Environmental Perchlorate Contamination: The Dose Response 

for Inhibition of Thyroidal Radioiodide Uptake in Humans, Envtl. Health Perspectives, Sep. 2002, 

at 927.] and other studies relied on by the NAS panel are studies of total exposure. The last 

approach posits that EPA could consider the comparative effect on iodine uptake inhibition (IUI) of 

perchlorate exposure in drinking water to other dietary goitrogens in determining whether there is 

meaningful opportunity for risk reduction. 

In Attachment 2 [See PDF of docket ID EPA-HQ-OW-2007-0068-0168], we discuss the 

supplemental or alternative approaches that EPA can adopt to directly answer the question of 

whether regulation of perchlorate in drinking water will result in meaningful reduction in human 

health risk. 

Response: EPA agrees that biomonitoring offers some unique advantages with this type of 

contaminant which is not metabolized and excreted via urine (and milk in lactating women). The 

limitation in the use of NHANES is it addresses ages 6 and above. 

However, EPA disagrees that biomonitoring data demonstrates that total perchlorate exposure from 

all sources is below the EPA’s health benchmark for US residents. The effect of additional 

perchlorate added via water in the Greer et al. study over the amounts in food and other iodine 

inhibitors in food was reflected in the RfD. It is unknown whether the background levels of 

inhibitors altered the shape of the dose response curve to either lessen or increase the dose of 

perchlorate required to detect iodine uptake inhibition in the subjects. We presume a straight line 

i.e., that regardless of the background in the subjects, the incremental additional perchlorate required 

was 0.07 ug/kg/day to arrive at the NOEL for the additional perchlorate. Given that this notice 

regards whether or not to regulate perchlorate in drinking water, allowing a normal background of 

goitrogens in the subjects' diets reveals the additional amount in water needed to produce inhibition. 

It could be argued that apportionment between food and water has already taken place since this is 

not total perchlorate, but added water over and above the food. Because these variables are 

unknown outside of a sequestration study where precise amounts of perchlorate from all food and 

water is measured, EPA assumes additional perchlorate from any source, food or water, produces 

the iodine uptake inhibition reflected by the RfD. 

Regarding the comment that EPA could consider the comparative effect on iodine uptake inhibition 

of perchlorate exposure in drinking water to other dietary goitrogens in determining whether there is 

meaningful opportunity for risk reduction, EPA believes that the approach has merit; however, a 

cumulative risk assessment would require significant new data collection and would unnecessarily 

delay regulatory decision making for perchlorate. The Administrator will make regulatory 

determinations on a case-by-case, contaminant specific basis. In making a regulatory determination, 

the Administrator considers the adverse health effect of the particular contaminant at issue as well as 

the occurrence or likelihood of occurrence of the contaminant in public water systems with a 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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frequency and at levels of public health concern. Finally, it is the sole judgment of EPA’s 

Administrator to determine whether there is a meaningful opportunity to reduce health risk for 

persons served by public water systems. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1724 

EPA Comment ID: 20616 

EPA Comment Code: 4000 

Comment: After reading the EPA report, it is clear the EPA did not consider the fact that 

perchlorate is concentrated many times (19X was cited) in lettuce, which is watered in California by 

perchlorate contaminated water. Studies of perchlorate concentrations in lettuce found in 

supermarkets across the US finds high concentrations of perchlorate in lettuce, which is usually 

grown in California. The EPA study did not utilize this information in its findings. Until the EPA 

allows this information into its deliberations, their study, and findings, are not complete. DOD has 

effectively blocked the lettuce findings, and President Bush has refused to allow the EPA to conduct 

further studies, saying we are at war, which protects DOD from the costs of clean-up. If the reader 

would consider his or her own family, women would probably be found taking Synthroid due to 

thyroid issues. Might the fact that women tend to eat more salads than men correlate? None of these 

issues are addressed by the EPA. 

Response: Leafy vegetables do concentrate salts such as perchlorate as water evaporates from 

leaves (evapotranspiration). EPA has evaluated early studies of perchlorate content of food and 

reported these findings in the May 1, 2007 Federal Register notice. The data from FDA's total diet 

study as well as biomonitoring studies by EPA/CDC have further refined the contribution of food 

to perchlorate exposure in various age/sex groups as discussed in the October 10, 2008 and August 

19, 2009 notices. EPA does not believe that the widespread presence of perchlorate in food 

overrides the need for public health risk reduction for persons served by PWSs with perchlorate 

contamination. EPA recognizes that a drinking water regulation would not eliminate total 

perchlorate exposure, but believes that the reduction in perchlorate exposure in drinking water 

presents a meaningful opportunity for health risk reduction for persons served by PWSs 

contaminated by perchlorate. 

Commenter Name: Apparent Mass Mailing #6 - Earth Justice 

EPA Document ID: EPA-HQ-OW-2008-0692-0972 

EPA Comment ID: 20886 

EPA Comment Code: 4000 

Comment: EPA's analysis fails to consider that the combination of food and drinking water 

exposure to perchlorate in the U.S. population exceeds the reference dose set by EPA. Nor does it 

incorporate the more protective methodology behind the recent state regulatory actions. These flaws 

must be remedied for the sake of the millions of U.S. families exposed to dangerous levels of 

perchlorate contamination. 

Response: EPA considers the combination of food and drinking water through the relative source 

contribution (RSC). The RSC is the percentage of the reference dose remaining for drinking water 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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after other sources of exposure to perchlorate have been considered (e.g., food). See the August 

2009 Federal Register notice (41887) for a detailed discussion of RSC derivation. 

Regarding the comment about incorporating methodologies behind recent state regulatory actions, 

States use different methodologies or assumptions to derive their own standard based on their 

unique exposure scenarios. EPA has used the best available peer reviewed science in making this 

regulatory determination. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 4110 Dietary studies – FDA’s 2005-2006 total dietary 

study (TDS) 

Individual Comments 

Commenter Name: 

Commenter Organization: Ag Council et al 

EPA Document ID: EPA-HQ-OW-2008-0692-1987 

EPA Comment ID: 20976 

EPA Comment Code: 4110 

Comment: FDA's Food Sampling Results Reveal that Perchlorate Concentrations are Below the 

Level of Concern and that Iodine intake Actually Exceeded NAS-Recommended Levels for all 

Groups Across the US Population. 

When perchlorate was first discovered in food, the FDA began sampling produce and bottled water 

in an effort to characterize perchlorate occurrence in food. FDA later expanded its perchlorate 

sampling effort to include other vegetables, fruits and milk to gain a greater understanding of the 

range of foods that contain perchlorate. FDA's efforts included a total dietary survey (TDS), the 

results of which were provided to US EPA for use in determining total perchlorate exposure in the 

US population. 

TDS is a market basket survey of various foods analyzed for perchlorate and iodine, conducted by 

FDA from 2003-2006. In early 2008, FDA published its testing results for 285 food samples in each 

of three cities in each of the four regions of the country. FDA evaluated the food data based upon 

estimated food consumption patterns of 14 age/sex groups from 6-11 month-old infants up to 70+ 

year-old men and women. 

FDA found that the average daily intake of perchlorate was well below both the NAS RfD and 

health reference level (HRL). FDA identified children 2 years of age as having the highest average 

intake of perchlorate at 0.35 to 0.39 ug/kg bw/day, which at the upper end is slightly more than half 

of the RfD, but still below the HRL. 

For iodine, FDA found that each of the 14 age/sex groups, including infants, children, and women 

of childbearing age exceeded the average intake levels estimated by the NAS to meet requirements 

for healthy individuals. 

In light of these findings, FDA continues to stand by its prior recommendation that consumers 

should not alter their infants' and children's diets and eating habits. Indeed, many of the foods at 

issue are major dietary sources of iodine and other nutritionally essential substances. 

Response: No response necessary to this summary of FDA TDS information. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21065 

EPA Comment Code: 4110 
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Comment: iii. Murray et al. (2008) 

The Food and Drug Administration (FDA) total diet study (TDS) was "designed to monitor the U.S. 

food supply for chemical contaminants, nutritional elements, and toxic elements." Based on 

measurements of perchlorate and iodine in market baskets, the Murray et al. report estimated intake 

doses. The sampling approach is based on "market baskets" that are collected four times per year. 

Each market basket contains 285 foods, collected simultaneously in three cities within a region. The 

modeled group estimated to have the greatest dietary exposure to perchlorate was children age 2 

(0.35 to 0.39 ug/kg-day). This is due to the high intake of dairy products coupled with low body 

weight. The modeled dose for the most sensitive population, the fetuses of pregnant women, was 

not specifically modeled, but the estimated dose for women of child bearing age was 0.09 to 0.11 

ug/kg-d.[FN3: The estimated doses for women ages 14-16, 25-30, and 40-45 were all 0.09 to 0.11 

ug/kg-d.] Adult men age 25 to 30 years old were estimated to be exposed to 0.08 to 0.11 ug/kg-day. 

Of the foods measured in this study, spinach, tomatoes, and cantaloupe had the highest levels of 

perchlorate at 40, 78, and 24.4 ug perchlorate/kg wet weight of food, respectively. 

This study can be used to estimate exposures to perchlorate based on actual food concentrations. 

Even at the highest estimate, this dose was less than the U.S. EPA RfD of 0.7 ug/kg-day. The study 

does not aim to evaluate overall body steady-state serum concentrations of perchlorate, only dose. 

Children age 2 have a higher renal excretion rate than adults or infants do, which would reduce their 

steady-state serum concentration despite the higher intake.[FN4: Perchlorate is a non-metabolized 

pharmaceutical agent with nearly complete urinary excretion. Data on adult and child clearances is 

available for other pharmaceuticals making it possible to extrapolate the rate of a child's clearance of 

perchlorate compared to an adult's. Based on the clearance of gabapentin, gentamicin, isepamicin, 

ticarcillin, and vancomycin, the clearance in a child is 1.6 times that of an adult (unpublished data).] 

Response: EPA does not believe that the widespread presence of perchlorate in food overrides the 

need for public health risk reduction for persons served by PWSs with perchlorate contamination. 

The Agency presented an extensive evaluation of dietary exposure to perchlorate in the October 

2008 and August 2009 notices (73 FR 60262; USEPA 2008a and 74 FR 41883; USEPA 2009b). EPA 

has used this dietary exposure data to account for the relative source contribution (RSC) of 

perchlorate from food. EPA recognizes that a drinking water regulation would not eliminate total 

perchlorate exposure, but believes that the reduction in perchlorate exposure in drinking water 

presents a meaningful opportunity for health risk reduction for persons served by PWSs 

contaminated by perchlorate. Please see response to comment code 5220 for a discussion of EPA’s 

revised approach to deriving potential HRLs. 

Commenter Name: Sonia Salas 

Commenter Organization: Western Growers Association on behalf of several California 

agriculture groups 

EPA Document ID: EPA-HQ-OW-2009-0297-0652 

EPA Comment ID: 28679 

EPA Comment Code: 4110 

Comment: US FDA's Food Sampling Results Reveal that Perchlorate Concentrations are Below 

any Meaningful Level of Concern and that Iodine Intake Actually Exceeds NAS- Recommended 

Levels for all Groups Across the US Population. 
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When perchlorate was first discovered in food, the U.S. FDA began sampling produce and bottled 

water in an effort to characterize perchlorate occurrence in food. FDA later expanded its perchlorate 

sampling program to include other vegetables, fruits and milk to gain a greater understanding of the 

range of foods containing perchlorate. FDA's work included a total dietary survey (TDS), the results 

of which were provided to US EPA for use in determining total perchlorate exposure in the US 

population. 

The Total Dietary Survey is a market basket survey of various foods analyzed for perchlorate and 

iodine, conducted by FDA from 2003-2006. In early 2008, FDA published its testing results for 285 

food samples in each of three cities in each of the four regions of the country. FDA evaluated the 

food data based upon estimated food consumption patterns of 14 age/sex groups from 6-11 monthold infants up to 70+ year-old men and women. 

FDA found that the average daily intake of perchlorate was well below both the NAS' 

recommended RfD and USEPA's current 15 ppb health reference level (HRL). FDA identified 

children 2 years of age as having the highest average intake of perchlorate at 0.35 to 0.39 ug/kg body 

weight/day, which at the upper end is slightly more than half of the RfD, but still below the HRL. 

Response: In the October 2008 preliminary regulatory determination, EPA had derived a single 

HRL of 15 μg/L based upon the RfD, an estimate of perchlorate exposure from food for pregnant 

women, and traditional adult body weight (70 kg) and drinking water consumption (2 L/day) values. 

This single HRL was derived to reflect exposure to a pregnant woman and her fetus, which the 

NRC identified as “the most sensitive population.” Since the NRC also identified infants and 

developing children as additional life stages, EPA derived potential alternative HRLs for 14 life 

stages (age groups) using the RfD and life stage-specific exposure information in the August 9, 2009, 

notice (74 FR 41883; USEPA 2009b). These levels range from 1 μg/L to 47 μg/L and are the 

concentrations of perchlorate in drinking water that may result in total perchlorate exposures (from 

food and water) greater than the RfD for individuals at each life stage. These HRLs are calculated 

based on individuals who consume an average amount of perchlorate from food (except for 

pregnant women where EPA used a 90th percentile dietary intake estimate), but who consume equal 

or more water on a per body weight basis than 90 percent of their cohorts. EPA is evaluating these 

potential alternative HRLs and considers them to be levels of public health concern for purposes of 

this determination. 

Commenter Name: Sonia Salas 

Commenter Organization: Western Growers Association on behalf of several California 

agriculture groups 

EPA Document ID: EPA-HQ-OW-2009-0297-0652 

EPA Comment ID: 28680 

EPA Comment Code: 4110 

Comment: These results, taken together with the results of EPA's 2006 tests of nearly 40,000 water 

samples from across the U.S.,[FN1: Office of Water: The Analysis of Occurrence Data from the 

First Unregulated Contaminant Monitoring Regulation (UCMR1) in support of Regulatory 

Determinations for the Second Drinking Water Contaminant Candidate List (EPA 815-D-06-008);] 

which show that perchorate levels were less than seven parts per billion in 99% of the samples, 

provide no evidence that individuals ingest perchlorate at daily doses exceeding the Reference Dose. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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They also suggest that there is little likelihood that such exposures would occur. This conclusion is 

further supported by data from the U.S. Centers for Diseases Control's National Health and 

Nutrition Examination Survey (NHANES) biomonitoring dataset (see below). 

Response: Since the NRC also identified infants and developing children as additional life stages, 

EPA derived potential alternative HRLs for 14 life stages (age groups) using the RfD and life stagespecific exposure information in the August 9, 2009, notice (74 FR 41883; USEPA 2009b). These 

levels range from 1 μg/L to 47 μg/L and are the concentrations of perchlorate in drinking water 

that may result in total perchlorate exposures (from food and water) greater than the RfD for 

individuals at each life stage. These HRLs are calculated based on individuals who consume an 

average amount of perchlorate from food (except for pregnant women where EPA used a 90th

percentile dietary intake estimate), but who consume equal or more water on a per body weight basis 

than 90 percent of their cohorts. EPA is evaluating these potential alternative HRLs and considers 

them to be levels of public health concern for purposes of this determination. The CDC NHANES 

biomonitoring data set does not include data for all life stages. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 4130 Dietary studies -- other studies, models, and data 

(besides FDA’s 2005-2006 TDS, and 2003-2005 exploratory data) 

Individual Comments 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group (PSG) 

EPA Document ID: EPA-HQ-OW-2007-0068-0170 

EPA Comment ID: 20289 

EPA Comment Code: 4130 

Comment: July 24, 2007 US Environmental Protection Agency Office of Water Docket (Mailcode 

2822T) 1200 Pennsylvania Avenue, NW Washington, DC 20460 

RE: Supplemental Comments on Regulatory Determinations Regarding Contaminants on the 

Second Drinking Water Contaminant Candidate List Rule, Docket ID: EPA-HQ- OW-2007-0068 

In May 2007, the US Food and Drug Administration posted a Preliminary Estimation of Perchlorate 

Dietary Exposure Based on FDA 2004/2005 Exploratory Data on the web at 

www.cfsan.fda.gov/~news/whatsnew.html. Perchlorate exposure from consumption of 27 foods 

and beverages was estimated via a Monte Carlo simulation. The Monte Carlo simulation sums 

perchlorate exposure values based on food intake and perchlorate concentration levels randomly 

drawn from a range of possible values for each food from a particular iteration to yield a total 

exposure for an individual. The summary of their analysis is presented in their Table as follows: 

[Table. Summary of Population-Based Perchlorate Exposures] 

FDA did not consider other dietary goitrogens such as nitrate and thiocyanate in their analysis in 

order to place these results in perspective. Although thiocyanate is the most significant dietary 

goitrogen that shares the same mechanism of action as perchlorate, the food content of thiocyanate 

precursors is not widely reported. On the other hand, the nitrate contents of various dietary sources 

has been widely reported in the peer reviewed literature and nitrate is known to share the same 

mechanism of action as perchlorate (competitive inhibition of iodine uptake by the thyroid). Nitrate 

is known to be approximately 1/240th as potent as perchlorate on a weight ingested basis in the 

inhibition of iodide uptake (IUI). (Tonacchera et al., 2004) 

Due to the data gap, the Perchorate Study Group (PSG) contracted with Kenny Crump and Cynthia 

Van Landingham of Environ in Ruston, LA to perform a similar Monte Carlo analysis of nitrate 

consumption to assess the relative importance of these two dietary goitrogens on IUI [See PDF of 

docket ID EPA-HQ- OW-2007-0168-0170]. Using the relative potencies of nitrate and perchlorate 

derived from Tonacchera, the nitrate data summaries from Crump & Van Landingham, Table 4 can 

be compared directly with the perchlorate summaries from FDA in their Table 2. These 

comparisons are presented below. 

[Table 2 See PDF of docket ID EPA-HQ-OW-2007-0168-0170] 
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Thus, this analysis indicates that dietary nitrate is two to three orders of magnitude more significant 

than dietary perchlorate in IUI by the thyroid. Controlling dietary perchlorate is thus relatively 

insignificant to overall thyroid health than is controlling dietary nitrate intake. 

Thank you for allowing us the opportunity to submit this supplemental information for 

consideration by the Agency in making a regulatory determination on perchlorate. 

Sincerely, Michael Girard The Perchlorate Study Group 

Attach: 

[Attachment - see PDF] 

Response: EPA considers the combination of food and drinking water through the relative source 

contribution (RSC). The RSC is the percentage of the reference dose remaining for drinking water 

after other sources of exposure to perchlorate have been considered (e.g., food). See the August 

2009 Federal Register notice (74 FR 41883; USEPA 2009b) for a detailed discussion of RSC 

derivation. EPA acknowledges that nitrate and thiocyanate have the same mode of action as 

perchlorate, and that the effects of combined exposure to perchlorate, nitrate, and thiocyanate are 

additive, EPA does not believe there are sufficient scientific data currently available to assess and 

characterize the combined risk of these contaminants. EPA has committed to a drinking water 

strategy that outlines four principles to expand public health protection for drinking water (USEPA, 

2010b). One of these principles is to address contaminants as groups. However, EPA does not 

believe that regulatory action to address perchlorate should be further delayed. Therefore, EPA 

intends to develop a proposed rule for perchlorate. At such time as a NPDWR is promulgated, EPA 

is required to review and revise, as appropriate, its drinking water standards at least every six years. 

Any revision must at least maintain or improve public health protection. When there are sufficient 

scientific data to assess the cumulative risks of perchlorate and other contaminants, EPA will review 

this information to evaluate whether any new or revised NPDWRs are appropriate. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association 

EPA Document ID: EPA-HQ-OW-2008-0692-1424 

EPA Comment ID: 20440 

EPA Comment Code: 4130 

Comment: Since the NRC published its findings in 2005, several studies have been completed that 

provide data necessary to evaluate; the, population exposure potential. In the study developed by 

Mendez et.al. (2008), probabilistic (Monte Carlo) simulation was used to estimate the potential 

contribution of drinking water to the aggregate perchlorate intake by the presumed most sensitive 

population, reproductive age women. The full report is attached as Appendix A [see PDF Docket 

ID EPA-HQ-OW-2008-0692-1424] to these comments. Food perchlorate concentration 

distributions were derived from the FDA 2004-5 Exploratory Sampling dataset. Food and 

waterconsumption data were obtained from the USDA Continuing Survey of Food Intake by 

Individuals (CSFII) from 1994-96 and 1998. The Monte Carlo simulation derives three distributions 

of perchlorate concentrations in drinking water, corresponding to "raw" data from EPA's UCMR1 

national perchlorate sampling, data from the UCMR1 with low-level "background" perchlorate 

concentrations added to a portion of the entry points below detection limits, and UCMR1 data for 
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large California systems, again with "background" perchlorate concentrations added to a proportion 

of non-detect observations. 

Inclusion of the estimated national drinking water distributions in the simulation resulted in 

increases in estimated median perchlorate intakes 3-20 percent greater than those seen when only 

dietary sources were evaluated. The perchlorate intake distributions estimated based on diet and 

water intake were found to be very similar to the distributions estimated based on perchlorate 

excretion data from 2001-2002 and 2003-2004 National Health and Nutrition Examination Survey 

(NHANES) data sets. The intake estimates based on diet and water and estimates derived from 

urinary excretion analyses suggestthat approximately two to five percent of reproductive age women 

in the U.S. receive perchlorate intake greater than 2x10-4 mg/kg-day, which is approximately onethird of the RfD for perchlorate. This proportion does not appear to be strongly affected by 

reasonable assumptions related to background drinking water contamination. The proportion of 

women with intakes above the RfD (7x10-4 mg/kg- day) cannot be estimated accurately from either 

the dietary intake analysis or NHANES data because of the sparcity of data in the upper percentiles 

of the distribution, but is likely to be considerably lower than two percent nationally. In addition, the 

proportion of women adversely effected by perchlorate exposure is likely to be even lower, since 

perchlorate appears to adversely effect thyroid function only in women with insufficient iodine 

intake. (Blountet al. 1996). 

This finding, that the total dietary exposure (food and drinking water) of reproductive age women in 

the U.S. is approximately one-third of the RfD for perchlorate at the 95th percentile, is 

complimentary to the finding referenced in the proposed decision based on a joint assessment 

prepared by EPA-CDC. Given this evidence related to limited exposure potentials and estimated 

intakes well below the RfD it is clear there is limited potential for perchlorate to present a significant 

adverse affect on the nation's health, including sensitive subpopulations. 

Response: EPA disagrees and has decided to regulate perchlorate in drinking water. See response to 

comment code 6120. EPA estimates that at least 5.1 to 16.6 million people are served by PWSs, for 

which we have data, that have perchlorate contamination. EPA has determined that a NPDWR for 

perchlorate could reduce perchlorate exposures for these populations to levels below the potential 

alternative HRLs that EPA has identified as levels of public health concerns for purposes of this 

determination, and that such exposure reductions present a meaningful opportunity for the 

reduction of health risks for persons served by PWSs. 

Commenter Name: Kathy Curtis 

Commenter Organization: Alliance of Nurses for Healthy Environments (ANHE) 

EPA Document ID: EPA-HQ-OW-2009-0297-0651 

EPA Comment ID: 28545 

EPA Comment Code: 4130 

Comment: EPA must also consider other exposure pathways and additional contaminants in the 

environment that impact thyroid function when establishing the MCL. Studies of perchlorate levels 

in food, including breast milk, show that the population is exposed through multiple pathways in 

addition to contaminated drinking water. 
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Response: See response to comment ID 20289 under comment code 4130. Additionally, EPA does 

apportion the exposure to perchlorate to food and derived the drinking water allowance considering 

the portion of the RfD already used by food. 

Commenter Name: Robert E. Brackett 

Commenter Organization: Grocery Manufacturers Association (GMA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0413 

EPA Comment ID: 28706 

EPA Comment Code: 4130 

Comment: GMA is concerned that Environmental Protection Agency's (EPA) approach to 

assessing potential risks of perchlorate in drinking water will be widely misunderstood and 

misinterpreted, leading to confusion and unnecessary concern among US consumers, and food 

importers, global policy makers, and regulatory bodies about perchlorate in US food products. GMA 

believes that sound public health policy requires that the relevant government agencies, including 

EPA, send a clear and consistent message to consumers that any hypothetical risks of perchlorate 

exposure to pregnant women and mothers of infants estimated by EPA are easily avoided by eating 

iodine-rich foods or taking an iodine supplement. This approach confers the double benefit of 

decreasing risk of disease associated with inadequate iodine intake as well as mitigating any potential 

risks of environmental exposure to perchlorate. We will elaborate below. 

First, it is important for EPA to be clear with the public that exposure to perchlorate, or to other 

substances in the diet that may interfere with iodine uptake by the thyroid, is only a potential 

problem in individuals with iodine deficiency. There is no evidence that iodine deficiency is currently 

a serious situation in the United States.[FN1: FDA has estimated iodine intake by the US population 

using data from the Agency's Total Diet Study 

(http://www/fda.gov/Food/FoodSafety/FoodContaminantsAdulteration/ChemicalContamin 

ants/Perchlorate/ucm077572.htm)] 

Based upon common food consumption patterns in the United States, and the availability of iodine 

within the US diet, only those individuals consuming highly restrictive diets or those deliberately 

avoiding iodine are at high risk of deficiency. In addition to naturally rich sources of iodine, such as 

fish and shellfish, iodine can be found in meat, poultry, and dairy products as well as in many 

manufactured food items including cereals and baked goods. Further, table salt is frequently 

consumed in an iodized form. Many dietary supplements, including prenatal multivitamin and 

mineral supplements contain iodine.[FN2: C Fields, M Dourson, J Borak. Iodine-deficient 

vegetarians: a hypothetical perchlorate-susceptible population? Regulatory Toxicology and 

Pharmacology 42 (2005):37-46] Despite the fact that data from NHANES I and NHANES III 

surveys suggested a decline in iodine consumption, data from more recent NHANES analyses show 

that iodine consumption has stabilized to a median level considered adequate based upon the World 

Health Organization guidelines for population adequacy.[FN3: KL Caldwell, R Jones, JG Hollowell. 

Urinary Iodine Concentration: United National Health and Nutrition Examination Survey 2001-

2002. Thyroid 15(7) 2005: 692-699] The Institute of Medicine's Food and Nutrition Board Dietary 

Reference Intake report for iodine concluded that infants under six months of age fed a diet 

exclusively of breastmilk have adequate and appropriate intake levels to support normal growth and 

development.[FN4: http://www.nap.edu/catalog.php?record_id=10026] In addition, infant formula 

manufacturers are required to fortify infant formula sold in the United States with iodine based 
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upon the Food and Drug Administration's (FDA) infant formula composition regulations found at 

21 CFR 107. 

There is no evidence of pervasive iodine deficiency in the United States in infants, children or adults. 

Some populations are hypothetically more at risk for effects of perchlorate consumption, most 

notably women of child-bearing age and pregnant women. Because of inadequate iodine 

consumption during pregnancy can lead to negative birth outcomes, any further reduction uptake by 

the thyroid from exposure to perchlorate could pose a risk. However, there is no evidence of 

widespread iodine deficiency among women of childbearing age or pregnant women in the United 

States. Therefore, any potentially susceptible subpopulation could be targeted with interventions 

such as education about diet during pregnancy and food sources of iodine, or supplementation. 

Adequate prenatal care should include an evaluation of a women's diet to assess for potential 

micronutrient deficiencies and appropriate counseling to help women plan their diets to address 

their changing nutrient needs during pregnancy should be provided. 

Response: EPA agrees that promoting iodide nutrition is good public health policy and may have a 

positive influence in reducing the iodide uptake inhibition effects associated with exposure to 

perchlorate. However, the Agency does not think it is appropriate to rely on the promotion of 

iodide nutrition in this case, especially since these activities are outside of EPA’s SDWA authority. 

The three SDWA criteria for a positive regulatory determination have been satisfied. While the 

health concerns associated with perchlorate may be addressed through other means, it is the 

Administrator’s judgment that a standard limiting perchlorate in drinking water can reduce health 

risk, particularly to fetuses, infants and children. 

Commenter Name: Robert E. Brackett 

Commenter Organization: Grocery Manufacturers Association (GMA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0413 

EPA Comment ID: 28708 

EPA Comment Code: 4130 

Comment: GMA notes with interest the draft review of the EPA perchlorate assessment by the 

EPA Office of Inspector General (OIG draft)[FN5: 

http://www.epa.gov/oig/reports/2009/20081230-2008-0010.pdf]. The OIG draft points out that 

there are other compounds occurring naturally in foods that act in similar ways as perchlorate, and 

that regulating the perchlorate level in drinking water is therefore unlikely to make any material 

difference. The best way to protect public health would be to assure that the iodine status of 

sensitive subpopulations is adequate. As discussed above, there is no evidence that the iodine status 

of sensitive subpopulations is inadequate, we agree with OIG that promoting adequate iodine intake 

by the population appears to be a superior approach to regulating perchlorate as a contaminant in 

public drinking water systems. 

Third, GMA is concerned that EPA's approach to assessing potential risks of perchlorate in drinking 

water will lead to confusion and unnecessary concern among importers of US food products about 

the potential for perchlorate in commodities and food products exported by the United States. FDA 

has reported finding perchlorate in targeted monitoring of some foods, and continues to test 

additional food types for perchlorate to further enhance the assessment of dietary exposure to 

consumers. EPA's concern is manmade sources of perchlorate, but perchlorate is known to form in 

the atmosphere and to occur naturally in the environment, notably in certain geographic deposits 
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mined for fertilizer, the safety of perchlorate in food is scheduled for thorough evaluation on an 

international basis by the Joint FAO-WHO Expert Committee on Food Additives and 

Contaminants (JECFA) in 2010.[FN6: Tolerable Daily Intakes (TDIs) established by JECFA form 

the basis for food standards and maximum residue limits (MRLs) in foods established by the Codex 

Alimentarius Commission (Codex). Codex was created in 1963 by FAO and WHO to develop food 

standards, guidelines and related texts such as codes of practice under the Joint FAO/WHO Food 

Standards Programme. The main purposes of this Programme are protecting health of the 

consumers and ensuring fair trade practices in the food trade, and promoting coordination of all 

food standards work undertaken by international governmental and non-governmental organizations 

( http://www.codexalimentarius.net/web/index_en.jsp).] 

In summary, we reiterate that sound public health policy requires the relevant government agencies, 

including EPA, to send a clear and consistent message to consumers. Any hypothetical risks of 

perchlorate exposure to pregnant women and mothers of infants as estimated by EPA are easily 

avoided by eating iodine-rich foods or taking an iodine supplement. This approach will not only 

mitigate any risk that may be associated with environmental exposure to perchlorate, but will also 

decrease the risk of disease associated with inadequate iodine intake. 

GMA appreciates this opportunity to provide comments on EPA's approaches to the interpretation 

of the scientific data relevant to a regulatory determination for perchlorate in drinking water. We 

urge EPA to work in concert with FDA to assure that consumers are given balanced and consistent 

advice and perspective concerning the theoretical risks of chemical exposures, including risks to 

sensitive subpopulations. Providing this balance and perspective is particularly critical in the case of 

chemicals that may occur in foods that are sources of essential nutrients conferring substantial 

overall net benefits to health. 

Sincerely yours, Robert E. Brackett, Ph.D. Senior Vice President and Chief Science and Regulatory 

Affairs Officer 

Response: See response comment ID 28706 under comment code 4130. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group (EWG) 

EPA Document ID: EPA-HQ-OW-2009-0297-0499 

EPA Comment ID: 28932 

EPA Comment Code: 4130 

Comment: EWG supports the agency's decision to develop HRLs based on life stage and drinking 

water ingestion rates but we would like to bring attention to some findings from a recent CDC study 

of infant formula contamination that we believe would change the HRLs for infants six months of 

age and under. In this study, researchers tested 15 brands of powdered infant formula for 

perchlorate and found contamination in every brand; the two most contaminated brands, made from 

cow's milk, accounted for 87 percent of the U.S. powdered formula market in 2000 (Schier et al 

2009). 

In Table 4 of the CDC study, the researchers estimate the minimum water perchlorate concentration 

needed to reach the current RfD for infants at one month and six months of age at different body 

weight percentiles. At the highest perchlorate concentration found in the formula samples (5.05 
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ug/l), the researchers found the estimated minimum water perchlorate concentration needed to 

reach the RfD was zero for the following four exposure scenarios: 

- One month old infant, 10th percentile body weight - One month old infant, 50th percentile body 

weight - One month old infant, 90th percentile body weight - Six month old infant, 90th percentile 

body weight 

In fact, in all four of these exposure scenarios, infants would exceed the current RfD from formula 

consumption even with perchlorate levels at zero in the water used to reconstitute it. A recent GAO 

report found that by six months of age, less than 30% of infants are exclusively breast-fed (GAO 

2006); in addition, powdered infant formulas account for 50 to 60% of the total infant formula 

market. This means that millions of infants per year may be exposed to powdered infant formula 

that is so heavily contaminated with perchlorate that formula exposures alone in these infants may 

exceed the current RfD. 

These results suggest that for infants six months of age and younger who are fed powdered formula, 

there is no safe HRL since any can of powdered formula may be contaminated with perchlorate at 

high enough concentrations that formula consumption alone results in exposures above the RfD. 

EWG recommends that the agency incorporate these exposure dosing scenarios from the formula 

study and modify the HRLs for infants six months and younger to reflect these findings. 

Response: EPA derived potential alternative HRLs for 14 life stages (age groups) using the RfD 

and life stage-specific exposure information in the August 9, 2009, notice (74 FR 41883; USEPA 

2009b). These levels range from 1 μg/L to 47 μg/L and are the concentrations of perchlorate in 

drinking water that may result in total perchlorate exposures (from food and water) greater than the 

RfD for individuals at each life stage. These HRLs are calculated based on individuals who consume 

an average amount of perchlorate from food (except for pregnant women where EPA used a 90th

percentile dietary intake estimate), but who consume equal or more water on a per body weight basis 

than 90 percent of their cohorts. EPA is evaluating these potential alternative HRLs and considers 

them to be levels of public health concern for purposes of this determination. 
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EPA Comment Code: 4210 Biomonitoring -- urinary data from the 2001-2002 

NHANES study, and EPA/CDC’s NHANES-UCMR analysis 

Individual Comments 

Commenter Name: Gregg Grunenfelder 

Commenter Organization: Washington State Department of Health; and Oregon Department of 

Human Services 

EPA Document ID: EPA-HQ-OW-2008-0692-1529 

EPA Comment ID: 20456 

EPA Comment Code: 4210 

Comment: Blount, et al. [FN12: Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, and 

Caldwell KL. 2006. Urinary Perchlorate and Thyroid Hormone Levels in Adolescent and Adult Men 

and Women Living in the United States. Environmental Health Perspectives (114)12: 1865-71.] 

evaluated 2001-2002 biomonitoring results from the National Health and Nutrition Examination 

Survey (NHANES) looking at urinary perchlorate, urinary iodine, and thyroid hormone levels and 

determined that total thyroxine (T4) and thyroid stimulating hormone (TSH) levels were related to 

urinary perchlorate in women. TSH and T4 levels were used as indicators of how well the thyroid 

was functioning. TSH causes the thyroid gland to produce triiodothyronine (T3) and T4. Both 

hormones are needed for normal brain development. Perchlorate was a significant positive predictor 

of TSH in women with urinary iodine >100 ug/l and significant positive predictor of TSH and 

negative predictor of T4 in women with low urinary iodine (< 100 ug/l). This implies that women 

and fetuses of women with low dietary intake of iodine can be impacted by perchlorate at current 

exposure levels in the United States population. This is especially of concern because recent 

NHANES data show that nearly 17% of reproductive aged women in the United States have urinary 

iodine levels less than 50 ug/l. The World Health Organization classifies someone as being iodine 

deficient at a urinary iodine level below 100 ug/l. 

Response: EPA agrees that low iodide nutritional status increases the likelihood of negative impacts 

due to perchlorate. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20906 

EPA Comment Code: 4210 

Comment: * EPA presents results from an unpublished study and relies on this study to justify a 

HRL of 15 ug/L (ppb) for perchlorate in drinking water, although this study does not look at risks 

to young children or breast-fed infants; 

Response: In the October 2008 preliminary regulatory determination, EPA had derived a single 

HRL of 15 μg/L based upon the RfD, an estimate of perchlorate exposure from food for pregnant 

women, and traditional adult body weight (70 kg) and drinking water consumption (2 L/day) values. 

This single HRL was derived to reflect exposure to a pregnant woman and her fetus, which the 

NRC identified as “the most sensitive population.” The study supporting this HRL was made 

available to the public through the regulations.gov web site and was peer reviewed outside the 
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Agency. The study focused on the most sensitive life stage available in the data (biomonitoring data 

are not available for children under the age of 6). 

In the August 9, 2009, notice (74 FR 41883; USEPA 2009b), EPA derived potential alternative 

HRLs for 14 life stages (age groups) using the RfD and life stage-specific exposure information. 

These potential alternative HRLs are the concentrations of perchlorate in drinking water that may 

result in total perchlorate exposures (from food and water) greater than the RfD for individuals at 

each life stage. These potential alternative HRLs are calculated based on individuals who consume 

an average amount of perchlorate from food (except for pregnant women where EPA used a 90th 

percentile dietary intake estimate), but who consume equal or more water on a per body weight basis 

than 90 percent of their cohorts. 

EPA is evaluating these potential alternative HRLs and considers them to be levels of public health 

concern for purposes of this determination. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20914 

EPA Comment Code: 4210 

Comment: EPA presents new information from unpublished study that does not include young 

children: In its assessment, EPA presents an unpublished study in which EPA and CDC researchers 

merged urine perchlorate levels from the NHANES study and water contamination data from the 

Unregulated Contaminants Monitoring Regulation with the goal being to "derive the dose of 

perchlorate coming from food alone by eliminating possible sources of water contribution" (EPA 

2008). Individuals from the NHANES study were categorized into three groups depending on 

whether the counties in which they resided were found to have drinking water contaminated with 

perchlorate or not. Using this approach, EPA was able to estimate daily perchlorate intakes for those 

with likely perchlorate exposure through drinking water and those without; EPA concluded that 

"The mean total exposure for people that are more likely to be exposed to perchlorate in food and 

water was calculated to be 0.101 ug/kg/day. The average exposure for people more likely to be 

exposed to perchlorate from food alone was 0.090 ug/kg/day" (EPA 2008). 

This approach allows EPA to estimate that the population they consider to be most at risk, pregnant 

women and the developing fetus, can be exposed to perchlorate levels in drinking water as high as 

15 ug/L and still not exceed the RfD. The most glaring flaw with EPA’s study is that it does not 

include young children. The FDA research establishes that young children have the highest 

perchlorate exposures from food and therefore, are most likely to exceed EPA’s RfD from 

additional exposures to contaminated drinking water. The NHANES data does not include 

information on children under the age of 6 so EPA’s study using NHANES data has an enormous 

data gap which basically invalidates the findings from this study. 

Response: 

EPA believes that the UCMR-NHANES data merge is valid for the age groups that were 

represented. The study was peer reviewed outside the Agency and made available to the public 

through the Regulations.gov web site. EPA has incorporated analyses of these life stages less than 
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six years of age in the 2009 August Federal Register Notice using data from FDA Total Diet Study 

to estimate dietary exposure. 

Commenter Name: Matt Lewis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2116 

EPA Comment ID: 21966 

EPA Comment Code: 4210 

Comment: Perchlorate can cause massive problems to growth, health, and development of 

children. A study by the Centers for Disease Control detected perchlorate in one out of 2,820 

people. The sources for these contaminations range from Food to Groundwater to Breast Milk. The 

Food and Drug Administration found perchlorate in 74% of all foods tested. Future Generations 

will face mental retardation, loss of hearing, and deficits in motor skills if further contamination 

continues. 

Response: EPA has decided to regulate perchlorate in drinking water. See response to comment 

code 6120. Also see response to comment ID 20886 under comment code 4000 for a discussion of 

how EPA considered exposure to perchlorate from food. 

Commenter Name: Tina Carroll 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2189 

EPA Comment ID: 22381 

EPA Comment Code: 4210 

Comment: According to your own website, ?Tests of drinking water at APG have detected 

perchlorate in four production wells and in the finished water supply for the city of Aberdeen.? 

Additionally, in 2004/2005 exploratory surveys, the FDA found ranging perchlorate levels in raw 

milk in Maryland. 

Response: EPA has decided to regulate perchlorate in drinking water. See response to comment 

code 6120. Also see response to comment ID 20886 under comment code 4000 for a discussion of 

how EPA considered exposure to perchlorate from food. 

Commenter Name: Brenda Lewis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2191 

EPA Comment ID: 22391 

EPA Comment Code: 4210 

Comment: Perchlorate can cause massive problems to growth, health, and development of 

children. A study by the Centers for Disease Control detected perchlorate in one out of 2,820 

people. The sources for these contaminations range from Food to Groundwater to Breast Milk. The 

Food and Drug Administration found perchlorate in 74% of all foods tested. Future Generations 

will face mental retardation, loss of hearing, and deficits in motor skills if further contamination 

continues. 
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Response: EPA has decided to regulate perchlorate in drinking water. See response to comment 

code 6120. Also see response to comment ID 20886 under comment code 4000 for a discussion of 

how EPA considered exposure to perchlorate from food. 

Commenter Name: Richard M. Peekema 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0419 

EPA Comment ID: 28684 

EPA Comment Code: 4210 

Comment: Comment on EPA-HQ-OW-2009-0297 

This document gives a detailed review made earlier of the 2006 CDC urinary analysis data. That 

review raised questions that are still relevant to the discussion of MCL levels for drinking water. In 

the pages that follow, a number of conclusions can be reached. 

SUMMARY AND CONCLUSIONS 

1. Perchlorate was detected and quantified in the urine of all 2820 samples tested with a new 

analytical technique. 50% of those samples exceeded the 4 ppb median value, and 10% of those 

samples exceeded 10 ppb. That urinary perchlorate could not be explained as coming from water 

but instead being continually re- supplied by the food being eaten. 

2. The correlation of the thyroid T4 hormone with urinary perchlorate as reported by Blount et al. 

could not be repeated exactly because the sample elimination criteria were insufficiently detailed. A 

least squares fit to all the data showed less correlation than Blount reported. The scatter plot of the 

data being correlated deserves as much consideration as correlation coefficients and relevance 

numbers reported by the statistical analysis. A search for a similar correlation between T4 and nitrate 

proved negative. 

3. Iodide deficiency in women of child bearing age appears to define the population at greatest risk 

to perchlorate in the drinking water. The percentage of such women appears to be increasing over 

time, presumably from reduced iodized salt intake being invoked by personal dietary responses to 

public clamor over excessive salt. A water contaminant specification based on a population that has 

other means to control its risk but fails to do so is also not appropriate. 

4. The effects of thiocyanate and nitrate cannot be ignored. But the levels of those ions in the 

population at risk also change with time. Reduced smoking in the population, and better control of 

nitrate runoff into drinking water aquifers will change the effect of those ions over time. Like the 

changing iodide deficiency over time, it is inappropriate to regulate a contaminant level that will 

change as the population at risk changes. The conclusions of the OIG report are endorsed. 

Respectfully submitted, Richard M. Peekema, retired chemist San Jose, CA 

Response: EPA will consider the best available data in evaluating the potential effects of 

perchlorate and exposure to the public. This includes the study by Blount and others that described 

their analysis of NHANES data. The findings and limitations of this study have been described in 

previous federal register notices concerning perchlorate in drinking water. 
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EPA agrees that perchlorate exposure may result from both food and drinking water. Previous 

analyses have estimated the portion of the perchlorate exposure from food. EPA considered the 

portion of perchlorate exposure from food in developing the potential alternative HRLs. See 

responses to comment IDs 20616 and 20886 under comment code 4000. 

Analyses performed by Blount et al. depend upon weighting of subjects with respect to their 

representation for the population. Without application of appropriate weighting, the analysis cannot 

be properly reproduced. 

EPA agrees that data indicate an increase in the number of women exhibiting low iodide status. 

However, this is only one of a variety of factors that will be considered in determining whether a 

NPDWR for perchlorate is warranted. Additional consideration of exposure and developmental 

stage will also be important factors to evaluate as EPA develops the proposed NPDWR. 

EPA received a number of comments that the Agency should consider the comparative effect on 

iodine uptake of perchlorate exposure in drinking water to nitrate and thiocyanate exposure in 

drinking water in determining whether there is a meaningful opportunity for risk reduction. EPA’s 

Office of Inspector General (USEPA, 2008c) believes that a NPDWR for a group of chemicals may 

be appropriate based on a yet-to-be-conducted cumulative risk assessment that assesses and 

characterizes the combined human health risk from perchlorate, nitrate, and thiocyanate. 

While EPA acknowledges that nitrate and thiocyanate have the same mode of action as perchlorate, 

and that the effects of combined exposure to perchlorate, nitrate, and thiocyanate are additive, EPA 

does not believe there are sufficient scientific data currently available to assess and characterize the 

combined risk of these contaminants. EPA has committed to a drinking water strategy that outlines 

four principles to expand public health protection for drinking water (USEPA, 2010b). One of these 

principles is to address contaminants as groups. However, EPA does not believe that regulatory 

action to address perchlorate should be further delayed. Therefore, EPA intends to develop a 

proposed rule for perchlorate. 

Commenter Name: Richard M. Peekema 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0419 

EPA Comment ID: 28685 

EPA Comment Code: 4210 

Comment: CDC URINE PERCHLORATE ANALYSES 

In 2006 the US Center for Disease Control (CDC) released supplemental analyses of urine samples 

collected for the earlier National Health and Nutrition Examination Survey (NHANES 2001-

2002).[FN1: http://www.cdc.gov/nchs/about/major/nhanes/] That new data was based on an 

improved analysis for perchlorate that was sensitive to 0.05 ppb,[FN2: Valentin- Blasini L, et al.; 

Anal. Chem. 77: 2475-2481 (2005)] and showed that every one of the participants had measurable 

levels of perchlorate in their urine. 

A statistical analysis of that data by Blount et al.[FN3: Blount BC, et al.; Environ Health Perspect. 

114: 1865-71 (2006)] claimed a correlation between very small amounts of perchlorate and reduced 

thyroid T4 hormones in iodide deficient women. They suggested that extremely low levels of 

perchlorate could affect the health of such women. The Blount article has been cited as evidence 

that the MCL of 6 ppb issued by the California Department of Public Health is too high. 
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The urinary analyses reported by the CDC included more than just perchlorate. Some 2800 

individual urine samples were analyzed by the CDC for perchlorate, thiocyanate, nitrate, and iodine. 

The results of those urine analyses were downloaded from the CDC, copied into a spreadsheet, and 

are analyzed here to a relatively simple extent. The frequency distribution of the perchlorate 

concentration is shown in Figure 1, and the cumulative distribution is shown in Figure 3. This 

population has a median urine perchlorate value of 4.0 ppb and a 10%-90% range of 1.2 - 10 ppb, 

surprisingly high values. 

Figure 1. Distribution of Perchlorate Analysis [see PDF docket ID EPA-HQ- OW-2009-0297-0419] 

Figure 3. Cumulative Distribution [see PDF docket ID EPA-HQ-OW-2009-0297-0419] 

What is the source of this perchlorate? The biological half life of perchlorate in the body is only 

eight hours.[FN4: Greer MA, et al.; Environ Health Perspect 110: 927-937 (2002)] That means that 

every 8 hours, an individual excretes half the perchlorate from his body. Since perchlorate is not 

detected in about 96% of community water supplies, water cannot be the source of that urinary 

perchlorate. The detected perchlorate must be coming from dietary intake (vegetables, grains, milk, 

meat, medication, etc.). The perchlorate intake must be continual or it would soon drop to zero. 

T4 HORMONE CORRELATION WITH URINARY PERCHLORATE 

Blount's statistical analysis (fn.3) showing a perchlorate-T4 correlation was based on a regression of 

serum T4 concentrations vs. the logarithm of the urinary perchlorate concentration. (Log[ClO4-] is a 

normally distributed parameter in the population, while [ClO4-] is not.) The CDC data on urinary 

analyses yielded 416 female persons of age >=12 years and <100 ppb urinary iodide [the criterion 

for iodide deficiency] and where T4 data were also available. Blount's correlation cites a sample size 

of 348, an elimination of 16% of the samples. The referenced article discusses complicated 

procedures that were used for eliminating samples, but gives few details of those methods. 

The results of this analysis here for 416 persons are summarized in the Table 4 below, with a 

comparison to Blount's numbers. The simple linear regression of the data without sample 

elimination and weighting shows some but much less correlation than Bount's. Figure 5 is a scatter 

plot for the perchlorate-T4 analysis using all the perchlorate data with no sample elimination. The 

line in this figure is calculated from the slope and intercept determined by the least squares fit to the 

416 data points. 

Figure 5. Correlation of Thyroid t4 with Perchlorate [see PDF docket ID EPA-HQ- OW-2009-

0297-0419] 

The correlation coefficients in Table 4 show a 10 fold better correlation by Blount than was 

achieved here. Blount declares his correlation to be statistically significant, but it apparently required 

extensive sample pruning to achieve those results. Our correlation here is weaker and would 

probably not be considered statistically significant. The CDC cautions against using their data 

without taking into account their study design and associated sample weights. When sample weights 

were incorporated into the frequency distribution, there was a small but not significant difference. 

With CDC sample weights, the median urinary perchlorate value was projected to be 3.8 ppb for the 

US population instead of 4.0 ppb for the sample population. However, the simple regression used in 

Table 4 and Figure 5 could not accommodate sample weights. 
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Did this analysis confirm Blount's correlation? These results are a limited confirmation of Blount's 

correlation, but not necessarily of his conclusions. The implied connection between perchlorate and 

T4 is tenuous at best. 

Table 4. Statistical Analyses of CDC Data [see PDF docket ID EPA-HQ- OW-2009-0297-0419] 

Attempts here using the released CDC data to demonstrate a similar effect by nitrate were 

unsuccessful. The results of simple linear regression of T4 levels against nitrate concentration and 

against log nitrate concentration are also summarized in Table 4 above. 

In this analysis, there seems to be no connection between nitrate and T4. All the anion data are for 

urinary concentrations, whereas the iodide uptake occurs in the serum near the NIS. One might 

expect perchlorate, which is metabolically inert, to have similar concentrations in serum and urine. 

On the contrary, nitrate is not equally inert, and there could be sizable differences between serum 

nitrate and urinary nitrate. That might explain why no nitrate effect was seen. 

The truly surprising result of the CDC data is the appearance of urinary perchlorate in every 

individual tested. Even more surprising is the 4 ppb median value. This can only be explained by 

food and not contaminated water. Considering the short half life of perchlorate in the body and for 

discussion assuming no source for it other than water, urinary concentrations are virtually equivalent 

to drinking water of the same concentration, namely more than 4 ppb for 50% of the population 

and more than 10 ppb for 10% of the population. 

Response: EPA believes that perchlorate exposure may result from both food and drinking water. 

Previous analyses have estimated the portion of the perchlorate exposure from food. EPA 

considered the portion of perchlorate exposure from food in developing the potential alternative 

HRLs. See responses to comment IDs 20616 and 20886 under comment code 4000. 

EPA believes that Blount’s interpretation of the relationship between T4 and perchlorate 

concentrations as reported in the peer reviewed literature are authoritative. Blount lists the 

shortcomings of his analysis in his paper. 

EPA does not believe that the widespread presence of perchlorate in food overrides the need for 

public health risk reduction for persons served by PWSs with perchlorate contamination. The 

Agency presented an extensive evaluation of dietary exposure to perchlorate in the October 2008 

and August 2009 notices (73 FR 60262; USEPA 2008a and 74 FR 41883; USEPA 2009b). EPA 

recognizes that a drinking water regulation would not eliminate total perchlorate exposure, but 

believes that the reduction in perchlorate exposure in drinking water presents a meaningful 

opportunity for health risk reduction for persons served by PWSs contaminated by perchlorate. 

Commenter Name: Richard M. Peekema 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0419 

EPA Comment ID: 28686 

EPA Comment Code: 4210 

Comment: IMPORTANCE OF OTHER ANIONS 
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Other anions cannot be ignored in assessing the level of perchlorate that sensitive individual can 

tolerate. The following table summarizes the CDC data released on urinary concentration and the 

relative potency established for them. Tonacchera et al.[FN5: Tonacchera M, et al.; Thyroid 14:1012-

1019 (2004)] have shown perchlorate to be 15, 30, and 240 times more potent than thiocyanate, 

iodide, and nitrate respectively, for inhibiting radioactive iodide uptake in the Human Sodium Iodide 

Symporter (NIS). The relative blocking potency values reported by Tonacchera are shown in Table 

2. 

Table 2. Anion Concentrations & NIS Potency [see PDF docket ID EPA-HQ- OW-2009-0297-

0419] 

In view of the urinary nitrate concentrations and the NIS potency shown in Table 2 above, one 

might expect to see a similar correlation between nitrate and the T4 hormone in iodide deficient 

women. Even though 240 times less potent than perchlorate, nitrate at 53,000 ppb would be 

equivalent to 221 ppb perchlorate which would have influenced T4. Attempts here using the 

released CDC data to demonstrate a similar effect by nitrate were unsuccessful. The results of simple 

linear regression of T4 levels against nitrate concentration and against log nitrate concentration were 

summarized earlier in Table 4. 

Response: Nitrate shares a common mode of action with perchlorate. However, data do not exist at 

this time to permit a scientifically defensible estimation of the relative potency of perchlorate and 

nitrate. The Tonacchera paper, an in vitro study evaluating the function of human receptors 

hybridized into animal cells, does not provide sufficient evidence to support a meaningful 

comparison. 
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EPA Comment Code: 4220 Biomonitoring -- breast milk studies discussed in 

the notice 

Individual Comments 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20992 

EPA Comment Code: 4220 

Comment: Finally, other recent studies have demonstrated that perchlorate is actively transported 

into mammary epithelial cells by the sodium-iodide symporter (NIS), resulting in an accumulation of 

perchlorate in breast milk.[FN27: Dohan, O, C Portulano, C. Basquin, A Reyna-Noyra, LM Amzel, 

and N Carrasco. 2007. The Na+/I- symporter (NIS) mediates electroneutral active transport of the 

environmental pollutant perchlorate. PNAS 104(51):20250-20255.],[FN28: Dasgupta, P. K., Kirk, A. 

B., Dyke, J. V., and Ohira, S.-I. (2008). Intake of Iodine and Perchlorate and Excretion in Human 

Milk. Environ. Sci. Technol. 42, 8115-8121.] In fact, in the Dasgupta study, perchlorate was 

concentrated in breast milk three times more than iodine. Also of note, only one infant out of 13 in 

this study was found to have adequate iodine intake. 

EPA has not adequately accounted for the concentrations of perchlorate in breast milk, the unique 

susceptibility of breast feeding neonates, or the fact that a significant portion of the U.S. population 

is iodine deficient, and therefore more susceptible to perchlorate toxicity. 

Response: In the October 2008 notice EPA discusses a number of studies that investigated 

perchlorate in human breast milk including perchlorate concentrations. See response to comment 

code 2100 for a discussion of EPA’s RfD and how that value both accounts for the most sensitive 

populations who are expose to perchlorate including iodine deficient populations. See response to 

comment code 5220 for a discussion of alternative HRLs. EPA has examined the relative sensitivity 

of the breast fed infant as part of its analysis for this regulatory determination as shown in Table 1 of 

the August 19 2009 Federal Register Notice. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21063 

EPA Comment Code: 4220 

Comment: i. Tellez et al. (2005) 

This was a longitudinal epidemiologic study of the effects of environmental perchlorate exposure on 

the thyroidal status of pregnant women and neonates. Perchlorate is found naturally at high levels in 

Chilean soils and water supplies. Some have questioned the relevance of this study to the U.S. 

population as historically, Chile has had high levels of dietary iodide supplementations. However, 

this supplementation has been decreased to levels that are similar to U.S. levels. In this study, the 

maternal excretion (and therefore ingestion) of iodine was at levels that were between those reported 

in NHANES I and NHANES III. The authors measured maternal and neonatal TSH, Tg, and free 
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T4. They also measured neonatal birth weight, length, and head circumference. They found that 

"...perchlorate in drinking water at 114 ug/L did not cause changes in neonatal thyroid function or 

fetal growth retardation." The levels of iodine in breast milk were not associated with perchlorate 

exposure. The levels of maternal iodine in urine were intermediate to that found in NHANES I and 

NHANES III and consistent with the World Health Organization (WHO) recommendations. This 

study strengthens the evidence that the RfD and HRL are conservative health based values. 

Response: The data underlying EPA notes that the data underlying the definition of iodide uptake 

inhibition as a precursor effect and the relationship of iodide uptake inhibition to the continuum of 

adverse outcomes reflects an understanding of effects in adults; it may not reflect the relationship of 

the precursor event to adverse outcomes in neonates and infants, who may not have iodide stores 

sufficient to offset the effects of reduced iodide uptake. The less resilient neonatal and infant 

system makes the exposure gap between a precursor event (iodide uptake inhibition due to 

perchlorate) and reduced T3/T4 levels likely to be narrower than for adults, and in fact, the 

distinction between the two may be blurred for the very young (Greer et al., 2002; Savin et al., 2003; 

van den Hove et al., 1999). The NRC noted that, “[T]he minimal prolonged decrease in thyroid 

hormone production that would be associated with adverse health effects is not known; any 

decrease is potentially more likely to have adverse effects in sensitive populations (people with 

thyroid disorders, pregnant women, fetuses, and infants) but data are not available to determine the 

magnitude of the decrease needed to cause adverse effects in those populations.” 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21064 

EPA Comment Code: 4220 

Comment: ii. Amitai et al. (2007) 

This ecological study aimed to "...assess the effect of gestational perchlorate exposure through 

drinking water on neonatal thyroxine (T4)" by comparing T4 levels among newborns whose 

mothers lived in areas where drinking water perchlorate levels were very high (>=340 ug/L), high 

(42-94 ug/L), or low (<3 ug/L). T4 levels were measured within 36 to 48 hours after birth, but there 

was no comment on whether the infants were breast fed or formula fed during the postnatal period. 

They found that there were no differences between neonatal T4 levels among the groups. This study 

provides evidence that the current RfD and values greater are conservative and health protective to 

the most sensitive individuals in the population. 

Response: Please see the response to comment ID 21063 under comment code 4220. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21076 

EPA Comment Code: 4220 

Comment: C. Breast Milk Studies 
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For many infants, breast milk is the sole source of food and therefore represents the greatest 

potential exposure to perchlorate. Although the population theoretically considered the most 

susceptible to the effects of high levels of perchlorate is developing fetuses, the effects of doses of 

perchlorate that are sufficiently high to block iodide uptake by the thyroid may alter normal growth 

and development in infants and children. Taken together, the following studies show that there is no 

association between environmentally relevant levels of perchlorate in drinking water and perchlorate 

or iodide in breast milk. Furthermore, no effect, adverse or otherwise, has been found due to 

environmentally relevant doses of perchlorate. 

i. Pearce et al. (2007b) 

The objective of the Pearce et al. study was "to determine whether breast milk iodine concentrations 

in Boston-area women are adequate for infant nutrition, and whether breast milk iodine 

concentrations may be associated with environmental perchlorate or cigarette smoke exposure." 

Pearce et al. measured breast milk iodine and perchlorate concentrations as well as iodine, 

perchlorate, and cotinine in urine. They then compared the levels found in breast milk to 17 

commercial infant formulae. Neither breast milk perchlorate nor urinary perchlorate levels were 

significantly correlated with breast milk iodine concentrations. Although perchlorate was detectable 

in infant formulae, the levels were lower than that in breast milk. A significant number of women in 

this study had iodine levels that were insufficient to meet the infant's needs, but the authors did not 

suggest this was due to perchlorate exposure or that it represents a chronic iodine deficiency. 

ii. Kirk et al. (2005) 

With the aim to determine what amount of perchlorate children are exposed to, Kirk et al. measured 

perchlorate and iodide levels in cow and human breast milk and compared these numbers to 

corresponding levels of perchlorate in drinking water in the area. Perchlorate was measurable in 81 

of the 82 samples. The average perchlorate levels in cow milk and human milk were 2 and 10.5 

ug/L, respectively. The maximum values of cow and human milk were 11 and 92 ug/L, respectively. 

There was no correlation between levels of perchlorate in breast milk and perchlorate in drinking 

water. They speculated that there was a correlation between higher levels of perchlorate and lower 

levels of iodine in breast milk.[FN7: The Kirk et al study uses an arbitrary and non-scientific method 

of speculating on this relationship. Kirk et al., write: "...we divide iodide levels [in human breast 

milk] in two groups, those above 60 ug/L and those below, this being the iodide content for many 

infant feed formulas"; "we...divide perchlorate content in two groups, high and low, in this case 

arbitrarily dividing the span of the observed perchlorate range in two equal halves." and "at this 

point with limited resources, we have been able to analyze only a few samples. Thus, they divide data 

set using no scientific rationale and then exclude data. The authors state, "If we take all the available 

data, there is no meaningful correlation between the perchlorate and iodide levels in breast milk."] 

However, this relationship only existed for the breast milk samples with the highest perchlorate 

levels (6 subjects out of 82). The authors recognize that this relationship may be coincidental due to 

the small number of samples with perchlorate levels greater than 10 ug/L, stating that "If we take all 

the available data, there is no meaningful correlation between the perchlorate and iodide levels in 

breast milk." As with previous studies, due to the design, this study is not able to evaluate a causal 

relationship. 

iii. Dasgupta et al. (2008) 
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In a very recently released study, Dasgupta et al. report the results of their study. "The objective of 

this present study was to study the excretion of perchlorate, thiocyanate, and iodine in milk and 

urine and relate the observed pattern within the broad framework of parallel / competitive transport 

by the NIS." Using breast milk and urine samples from 13 lactating women and using EPA default 

values for infant body weights and milk intakes, the authors mathematically modeled infant intakes 

and doses of iodide, perchlorate, and thiocyanate. They calculated the fraction of iodide, perchlorate, 

and thiocyanate in breast milk compared to the total that is excreted in both breast milk and urine. 

They used a ratio of these fractions in milk to determine the selectivity of either perchlorate or 

thiocyanate over iodide. They report "that 12 of 13 infants did not have an adequate intake of 

iodine...and 9 out of 13 infants were likely ingesting perchlorate at a level exceeding the reference 

dose..." They also concluded that the selectivity of perchlorate over iodide was 3.14 +/- 1.2. 

[Text Box: Taken together, studies on perchlorate in breast milk show that there is no association 

between environmentally relevant levels of perchlorate in drinking water and perchlorate or iodide in 

breast milk. Furthermore, no effect, adverse or otherwise, has been found due to environmentally 

relevant doses of perchlorate.] 

There are a number of concerns related to the experimental design of this paper. The population is 

small and there is no information on the selection process of the participants (e.g., they are not a 

random sample). There are only three biological variables that were measured from these women. 

The rest of the variables, including the variables used to derive the conclusions, are calculated from 

these these three in addition to using default values for infant intake and infant weights. The three 

measurements were the concentrations of of perchlorate, iodine, and thiocyanate in both urine and 

breast milk. Where other research has measured more biologically relevant information, such as 

serum concentrations of analytes which would be most reflective of relative concentrations at the 

NIS (Tonacchara et al., 2004; Pearce et al., 2007) thus, this work is limited. The estimated doses, the 

key variable for understanding possible NIS effects, are based on average body weight and intakes 

for an infant of that age with the concentration in breast milk. For such a simple and critical 

variable, it is suprising that actual body weights were not measured. 

In addition to study design, the data presented in this paper appears to contradict the interpretation 

by the authors of the paper. Based on estimated weights, the authors state that 9 out of 13 infants 

are consuming daily doses in excess of the RfD. However, from examining Table 1 from Dasgupta 

et al., there are 8 infants who exceed the RfD of 0.7 ug/kg-d (subjects 1, 2, 8, 11, 13, 15, 16, 20). 

Furthermore, if one reviews these estimates to measured variables, the infants with estimated 

perchlorate doses greater than the RfD are also estimated to have the greatest iodine intake. By 

plotting the values for total iodide excretion (column 4), total perchlorate excretion (column 7), 

estimated maternal breast milk iodide excretion (equivalent to estimated infant iodide intake; column 

5), and estimated maternal breast milk perchlorate excretion (product of total perchlorate excreted 

and percent of perchlorate in milk; column 7 x column 9) found in Table 1 of the paper, the results 

demonstrate that perchlorate and iodide are positively correlated (See Figure 3). If perchlorate was 

inhibiting the transport of iodide into milk, the association would be negative. 

[Figure 2: Plotting of data reported by Dasgupta et al., 2008 to illustrate the association between 

concentrations of iodine and perchlorate in urine and milk in lactating women - See PDF Docket ID 

EPA-HQ-OW-2008-0692-1855] 
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In addition to the concerns regarding interpretation of the data presented in this paper, there are 

concerns about the interpretation of their previous work (Kirk et al., 2005) and how that study 

impacts this recent study. For example, Dasgupta et al. state in this current paper that "in real 

mothers perchlorate does inhibit the transport of iodine into milk and because of competitive 

inhibition both analytes cannot be high at the same time." However, this statement is based on a 

previous study in which the researchers defined their cut off values[FN8: The cutpoints from Kirk 

et al. (2005) were defined as follows: High iodide in breast milk was greater than 60 ug/L and high 

perchlorate in breast milk was greater than 20 ug/L.] above which milk iodide or perchlorate were 

considered "high." They report that no milk samples had both high perchlorate and high iodide 

(Kirk et al., 2005). In the present study, they report the same trend although they do not define a cut 

off value. However, if the previous cut off values are applied to the current study, there are many 

samples that had simultaneously high perchlorate and iodide (Figure 3). Based on the previous 

conclusions about competitive inhibition of analytes (Kirk et al., 2005), this study does not 

demonstrate that perchlorate competitively inhibits iodide transport into milk at the concentrations 

experienced by these women. 

Response: In the October 2008 notice EPA discusses a number of studies that investigated 

perchlorate concentrations in human breast milk. Poor iodide uptake and subsequent impairment of 

the thyroid function in pregnant and lactating women have been linked to delayed development and 

decreased learning capability in their infants and children (NRC, 2005). Additionally, deficiency 

during childhood reduces child growth and cognitive motor function (Zimmerman, 2009). EPA has 

considered the portions of the population who are most sensitive to the effects of perchlorate and 

has determined that perchlorate may have an adverse effect on the health of persons. 

Please also see the response to comment ID 20992 under comment code 4220. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 4230 Biomonitoring -- other biomonitoring studies, 

models, and data for EPA to consider (other than NHANES and breast milk 

studies discussed in the notice) 

Individual Comments 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21077 

EPA Comment Code: 4230 

Comment: iv. Dohan et al. (2007) 

Animal, particularly rodent, studies are an implicit and valuable aspect of toxicology. There are, 

however, significant differences between human and rodent thyroid physiology. U.S. EPA states, 

"The fundamental mechanisms involved in the function and regulation of the pituitaryhypothalamus-thyroid system in rats are qualitatively similar to those in humans. However, 

differences in binding proteins, binding affinities of the proteins for the hormones, turnover rates of 

hormones, and thyroid stimulation by placental hormones lead to important quantitative differences 

between the two species. The biochemical and physiologic differences between rats and humans 

related to the thyroid affect their responses to goitrogens, such as perchlorate. Therefore, although 

studies in rats provide useful qualitative information on potential adverse effects of perchlorate 

exposure, they are limited in their utility for quantitatively assessing human health risk associated 

with perchlorate exposure" (U.S. EPA, 2005). 

The main purpose of the Dohan et al. publication is to demonstrate that perchlorate crosses cell 

membranes via the NIS; to demonstrate perchlorate's ability to be excreted in breast milk; and to 

develop a mathematical model to characterize their experimental results. The in vitro experiment 

and system they use is unique, creative, and provides the first evidence of perchlorate crossing a cell 

membrane using Mardin-Darby canine kidney (MDCK) cells transfected with the human NIS. It 

provides further evidence regarding questions about breast milk perchlorate levels and whether 

perchlorate blocks iodide at the symporter or competes against iodide in crossing the NIS. Thus, it 

decreases uncertainty in the risk assessment process. It is important to remember that this is the first 

study of its kind, it was conducted in vitro (cell culture), and it was conducted in a non-human cell 

line with artificially introduced human symporters. From a perspective on cell membrane transport, 

this work provides qualitative information. 

The author's discussion of the in vivo part of the study's relevance to environmental exposures of 

perchlorate and human health is, however, far reaching and not supported by the results of this 

experiment. High acute doses of perchlorate were given to the rats. The rats were given an 

intraperitoneal injection of nearly 8 mg/kg/d in addition to a drinking water exposure of 13.6 

mg/kg/d.[FN9: Assumes a 250 g rat with a daily water intake of 5.5 ml/100 g body weight.] The 

perchlorate doses administered in this study are high enough such that they should effectively block, 

with complete inhibition, iodide transport by the NIS in these rats, which provides no information 

about the effects at environmentally relevant doses. The results cannot be used to draw conclusions 

about what happens from a human health standpoint or mechanistic function at environmentally 

relevant concentrations. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Response: In the October 2008 notice EPA discusses a number of studies that investigated 

perchlorate concentrations in human breast milk. In the final regulatory determination notice EPA 

discusses the uncertainty about the point in the continuum of effects at which adversity occurs, and 

that these were major considerations in determining whether perchlorate is likely to have an adverse 

effect on health at a range of life stages. The conclusions of the study by Dohan et al. (2007) that 

NIS translocates perchlorate in epithelial mammary cells in vivo, based on rat models, represents a 

valuable contribution to the current scientific literature on the biological mechanisms of perchlorate 

uptake in mammary cells and its potential inhibitory effect on iodine, and its potential relevance to 

nursing neonates and infants. The data underlying the definition of iodide uptake inhibition as a 

precursor effect and the relationship of iodide uptake inhibition to the continuum of adverse 

outcomes reflects an understanding of effects in adults; it may not reflect the relationship of the 

precursor event to adverse outcomes in neonates and infants, who may not have iodide stores 

sufficient to offset the effects of reduced iodide uptake. The less resilient neonatal and infant 

system makes the exposure gap between a precursor event (iodide uptake inhibition due to 

perchlorate) and reduced T3/T4 levels likely to be narrower than for adults, and in fact, the 

distinction between the two may be blurred for the very young (Greer et al., 2002; Savin et al., 

2003; van den Hove et al., 1999). The NRC noted that, “[T]he minimal prolonged decrease in 

thyroid hormone production that would be associated with adverse health effects is not known; 

any decrease is potentially more likely to have adverse effects in sensitive populations (people 

with thyroid disorders, pregnant women, fetuses, and infants) but data are not available to 

determine the magnitude of the decrease needed to cause adverse effects in those populations.” 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 4300 Other perchlorate exposure studies, models, and 

data for EPA to consider (other than drinking water, diet, and biomonitoring) 

Individual Comments 

Commenter Name: Erik Lokensgard 

Commenter Organization: Division of the Biological Sciences, University of Chicago 

EPA Document ID: EPA-HQ-OW-2008-0692-0320 

EPA Comment ID: 19808 

EPA Comment Code: 4300 

Comment: I also recommend that pool chlorination systems be investigated for their potential role 

in perchlorate pollution. I'm sure that every family would prefer safe tap water to every family 

having a pool. 

Thank you for your time, Erik Lokensgard Division of the Biological Sciences University of Chicago 

Response: There may be perchlorate generated from stored hypochlorite solutions used in pools; 

however, under this action EPA is evaluating whether perchlorate should be regulated under the 

Safe Drinking Water Act. EPA is not seeking to determine the source of perchlorate as part of this 

action. 

Commenter Name: Jeremy Ginoza 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0635 

EPA Comment ID: 19983 

EPA Comment Code: 4300 

Comment: Perchlorate has been shown in animal studies to disrupt thyroid function (see references 

below). Please err on the side of less public health exposure, not more. Place the burden not on the 

delicate balance of human organs and tissues, but on profitable corporations to act responsibly. 

--Jeremy Ginoza, 4th year medical student 

Effects of maternal exposure to ammonium perchlorate on thyroid function and the expression of 

thyroid-responsive genes in Japanese quail embryos. Chen Y, Sible JC, McNabb FM. Gen Comp 

Endocrinol. 2008 Sep 6. 

"Our study shows that maternal perchlorate exposure led to embryonic hypothyroidism and may 

have interfered with embryonic development." 

"Embryos from eggs of perchlorate-exposed hens had hypertrophied thyroid glands and 

significantly lower thyroidal hormone storage, indicating hypothyroidism in these embryos. The 

embryonic hypothyroidism was associated with decreased embryonic growth, delayed hatching and 

greater mortality during hatching." 

Effects of prolonged exposure to perchlorate on thyroid and reproductive function in zebrafish. 

Mukhi S, PatiÃ±o R. Toxicol Sci. 2007 Apr;96(2):246-54. Epub 2007 Jan 6. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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"At 10 weeks of exposure, perchlorate at both concentrations caused thyroidal hypertrophy and 

colloid depletion." 

"In conclusion, prolonged exposure of adult zebrafish to perchlorate not only disrupts their thyroid 

endocrine system but also impairs reproduction and influences early F1 development." 

Response: EPA has decided to regulate perchlorate in drinking water. See response to comment 

code 6120. 
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EPA Comment Code: 5000 SDWA Criteria 

Individual Comments 

Commenter Name: Thomas L. Schoaf 

Commenter Organization: Cities of Litchfield Park and Goodyear, AZ 

EPA Document ID: EPA-HQ-OW-2008-0692-1552 

EPA Comment ID: 20519 

EPA Comment Code: 5000 

Comment: Under the Safe Drinking Water Act (SDWA), the EPA considers three criteria to 

determine if a drinking water standard should be established for a contaminant. Those criteria are 

that: i) there is a potential adverse human health effect ; ii) it is known or likely to occur at a level 

and frequency of concern in Public Water Systems (PWSs); and, iii) regulation presents a meaningful 

opportunity for health risk reduction. 

The EPA has determined that perchlorate presents an adverse human health effect. It is important 

to note that the EPA has also determined that perchlorate has a greater impact on sensitive 

populations, specifically pregnant women and developing fetuses. 

In evaluating potential exposure, the EPA concluded that perchlorate occurs at levels in excess of its 

selected health risk level threshold of 15 ug/L in less than 1% of PWSs. Even at this percentage, the 

EPA reports that its upper end estimate of population exposed to perchlorate at levels in excess of 

its selected health risk level is 2 million people. If the EPA had applied a more conservative relative 

source contribution factor, the upper end exposure estimate could be as high as 14 million people. 

We think that these exposure estimates alone warrant a determination that "regulation presents a 

meaningful opportunity for risk reduction." However, we are concerned that the EPA's evaluation 

of impacted public water supply systems (PWSs) may underestimate potential future exposure. By 

focusing only on known contamination at existing PWSs, the EPA does not consider likely impactsone of the SDWA criteria. For example, without the strength of a promulgated standard to require 

cleanup of the impacted aquifers at the PGA North Superfund Site, exposure to perchlorate will 

likely occur as future PWSs or future entry points to existing PWSs are brought on-line. By 

considering likely occurrences of perchlorate exposure, we believe that there is a known or likely 

exposure at a level and frequency of concern. 

Response: EPA has determined that regulation of perchlorate in drinking water systems presents a 

meaningful opportunity to reduce health risk for persons served by public water systems. See 

response to comment code 6120. 

Commenter Name: Ron Curry 

Commenter Organization: New Mexico Environment Department 

EPA Document ID: EPA-HQ-OW-2008-0692-1796 

EPA Comment ID: 20935 

EPA Comment Code: 5000 

Comment: Section 1412(b)(1)(A) of the SDWA provides that the EPA Administrator shall 

"promulgate a national primary drinking water regulation for a contaminant if the Administrator 

determines that: 
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(i) the contaminant may have an adverse effect on the health of persons; (ii)the contaminant is 

known to occur or there is a substantial likelihood that the contaminant will occur in public water 

systems with a frequency and at levels of public health concern; and (iii)in the sole judgment of the 

Administrator, regulation of such contaminant presents a meaningful opportunity for health risk 

reduction for persons served by public water systems. 

42 U.S.C. [section] 300g-1(b)(1)(A) (Westlaw 2008). 

Section 1412(b)(1)(C) of the SDWA further provides that in determining whether to regulate 

drinking water contaminants, the Administrator must take into consideration: 

the effect of such contaminants upon subgroups that comprise a meaningful portion of the general 

population (such as infants, children, pregnant women, the elderly, individuals with a history of 

serious illness, or other subpopulations) that are identifiable as being at greater risk of adverse health 

effects due to exposure to contaminants in drinking water than the general population. 

42 U.S.C. [section] 300g-1(b)(1)(C) (Westlaw 2008). 

The Environment Department respectfully submits that each of the three criteria in section 

1412(b)(1)(A) is met for perchlorate. Moreover, the risk of adverse health effects from perchlorate 

ingestion is greater for certain sensitive subgroups of the general population as described in section 

1412(b)(1)(C). 

Response: See response to comment code 6120. 

Commenter Name: Ron Curry 

Commenter Organization: New Mexico Environment Department 

EPA Document ID: EPA-HQ-OW-2008-0692-1796 

EPA Comment ID: 20939 

EPA Comment Code: 5000 

Comment: For EPA to base a final decision not to establish primary drinking water regulations for 

perchlorate under the SDWA on this analysis would be arbitrary, capricious, and not in accordance 

with the plain requirements of the SDWA. 

Response: See response to comment code 6120. 

Commenter Name: Caroline Baier-Anderson, PhD 

Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20942 

EPA Comment Code: 5000 

Comment: Perchlorate Meets the Three Criteria Needed to Justify Promulgation of a National 

Standard There are three criteria that must be met to justify the promulgation of a national public 

drinking water regulation: 
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a) The contaminant may have an adverse effect on human health b) The contaminant occurs with a 

frequency and at levels of public health concern, and c) The promulgation of standards presents a 

meaningful opportunity to reduce health risk. 

In our view, perchlorate meets all three of these criteria: perchlorate poses a significant health risk, is 

present at sufficient levels and in a sufficient number of public water systems to constitute a public 

health concern, and by promulgating a standard, EPA has a meaningful opportunity to reduce health 

risk. 

Response: See response to comment code 6120. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21093 

EPA Comment Code: 5000 

Comment: III. The Current Scientific Literature Provides Overwhelming Support for EPA's 

Findings under the Safe Drinking Water Act's Criteria for this Determination 

In the SDWA, EPA is directed by Congress to make a determination whether to set a National 

Primary Drinking Water Regulation (NPDWR) based on the following criteria: 

a) the contaminant may have an adverse effect on the health of persons; 

b) the contaminant is known to occur in public water systems with a frequency and at levels of 

public health concern; and, 

c) in the sole judgment of the Administrator, regulation of such contaminant presents a meaningful 

opportunity for health risk reduction for persons served by public water systems (73 FR 60264). 

Response: See response to comment code 6120. 

Commenter Name: Anthony Russo 

Commenter Organization: Chemistry Council of New Jersey (CCNJ) 

EPA Document ID: EPA-HQ-OW-2009-0297-0673 

EPA Comment ID: 28689 

EPA Comment Code: 5000 

Comment: The Agency must be able to support its determination with credible, properly 

interpreted science. Pursuant to the SDWA, EPA's final regulatory determination whether to 

establish a primary drinking water standard for perchlorate is based upon the following statutory 

criteria: 

* The contaminant may have an adverse effect on the health of persons; * The contaminant is 

known to occur or there is a substantial likelihood that the contaminant will occur in public water 

systems with a frequency and at levels of public health concern; and * In the sole judgment of the 
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Administrator, regulation of such contaminant presents a meaningful opportunity for health risk 

reduction for persons served by public water systems. 

Response: No response necessary for this comment. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28825 

EPA Comment Code: 5000 

Comment: September 17, 2009 

Water Docket Environmental Protection Agency Mailcode: 2822T 1200 Pennsylvania Ave., NW 

Washington, DC 20460 

Re: Comments on the Drinking Water: Perchlorate Supplemental Request for Comments Docket 

ID No. EPA-HQ-OW-2009-0297 

The Association of Metropolitan Water Agencies (AMWA) appreciates the opportunity to comment 

on the preliminary regulatory determination for perchlorate as listed in the August 19, 2009 Federal 

Register (74 FR 41883). AMWA strongly supports the process required by the 1996 Amendments to 

the Safe Drinking Water Act that places a strong emphasis on science and focuses on contaminants 

which: may have an adverse effect on humans; occur or are likely to occur at levels of public health 

concern; and provide a meaningful opportunity for health risk reduction. 

Response: No response necessary for this comment. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28871 

EPA Comment Code: 5000 

Comment: 4. Science-based considerations: The Safe Drinking Water Act (SDWA) has three 

requirements-all three of which must be met to satisfy the law. The scientific literature addresses 

these requirements for perchlorate. The science clearly shows EPA's statutory criteria for setting a 

standard are unmet in this case: 

Response: EPA disagrees with the statement that "the science clearly shows EPA's statutory criteria 

for setting a standard are unmet." In making final regulatory determinations, EPA uses the criteria 

mandated by the 1996 SDWA Amendments. Specifically, EPA has found that perchlorate may have 

an adverse effect on the health of persons, that perchlorate occurs or there is a substantial likelihood 

that perchlorate will occur in public water systems with a frequency and at levels of public health 

concern, and that regulation of perchlorate in drinking water systems presents a meaningful 

opportunity for health risk reduction for persons served by public water systems. The Federal 

Register notice for this action describes how EPA evaluated these three criteria in light of the best 

available peer reviewed data to make a preliminary regulatory determination for perchlorate. 
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EPA Comment Code: 5100 SDWA Criterion #1 – EPA’s determination that 

perchlorate may have adverse effects on the health of persons 

Individual Comments 

Commenter Name: Melanie A. Marty, Ph.D. 

Commenter Organization: Children's Health Protection Advisory Committee 

EPA Document ID: EPA-HQ-OW-2008-0692-0962 

EPA Comment ID: 20421 

EPA Comment Code: 5100 

Comment: The Safe Drinking Water Act (SDWA) requires the Administrator to establish an MCL 

when three conditions are met. The CHPAC feels strongly that all three conditions are met in the 

case of perchlorate. The first condition, that the contaminant has an adverse effect on the health of 

persons, is met for perchlorate. Perchlorate interferes with thyroid function and can lower 

circulating thyroid hormone levels in humans; lowered thyroid hormone levels and consequent 

impacts on the developing brain have been demonstrated in perchlorate-dosed animals. The 

developing fetus and infants are vulnerable to perchlorate due to the exquisite sensitivity of brain 

development to thyroid hormone levels, and the fact that newborns have no stores of this hormone. 

Response: See response to comment code 6120. 

Commenter Name: Ron Curry 

Commenter Organization: New Mexico Environment Department 

EPA Document ID: EPA-HQ-OW-2008-0692-1796 

EPA Comment ID: 20936 

EPA Comment Code: 5100 

Comment: As to the first criterion, it is without dispute that perchlorate in drinking water has 

anadverse effect on the health of persons. According to the National Research Council, perchlorate 

can adversely affect the function of the thyroid "because it is an ion that competitively inhibits the 

transport of iodide into the thyroid" by a protein known as the sodium/iodide symporter.[FN13: 

NATIONAL RESEARCH COUNCIL, HEALTH IMPLICATIONS OF PERCHLORATE 

INGESTION 6 (2005).] Iodide deficiency resulting from perchlorate ingestion is more likely to have 

a negative effect in sensitive populations, such as people with thyroid disorders, pregnant women, 

fetuses, and infants.[FN14: Id.] In pregnant women, severe iodide deficiency can result in major 

neurodevelopmental deficits and goiter in their offspring.[FN15: Id.] Lesser degrees of iodide 

deficiency may also cause important neurodevelopmental deficits in infants and children.[FN16: Id.] 

EPA expressly recognizes the adverse health effects of perchlorate ingestion.[FN17: See 73 Fed. 

Reg. 60262, 60275 (Oct. 10, 2008).] 

Response: EPA agrees with the commenter. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0415 

EPA Comment ID: 28846 

EPA Comment Code: 5100 
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Comment: The study by Mendez et.al. [FN13: Mendez, W., Dederick' E., and J. Cohen. 

2009. Drinking water contribution to aggregate perchlorate intake of reproductive-age women in the 

United States estimated by dietary intake simulation and analysis of urinary excretion data. Journal of 

Exposure Science and Environmental Epidemiology advance online publication 16 September 

2009.] further supports findings that the NOEL based RfD is sufficiently conservative and health 

protective of sensitive subpopulations. This study finds that the total dietary exposure (food and 

drinking water) of reproductive age women in the U.S. is approximately one-third of the RfD for 

perchlorate at the 95th percentile, which is complementary to the findings of the joint assessment 

prepared by EPA-CDC. Given this evidence related to limited exposure potentials and estimated 

intakes well below the RfD, it is clear that there is limited potential for perchlorate to present a 

significant adverse affect on the nation's health, including sensitive subpopulations. 

Response: 

EPA disagrees that there is a limited potential for perchlorate to present a significant adverse 

effect on the nation’s health, including sensitive subpopulations. EPA has determined that 

perchlorate occurs or there is a substantial likelihood that perchlorate will occur with a frequency 

and at levels of health concern in public water systems. EPA has made this determination by 

comparing the best available data on the occurrence of perchlorate in PWSs to potential health 

reference levels (HRLs) for perchlorate. 

Since the NRC also identified infants and developing children as additional life stages, EPA derived 

potential alternative HRLs for 14 life stages (age groups) using the RfD and life stage-specific 

exposure information in the August 9, 2009, notice (74 FR 41883; USEPA 2009b). These levels 

range from 1 μg/L to 47 μg/L and are the concentrations of perchlorate in drinking water that may 

result in total perchlorate exposures (from food and water) greater than the RfD for individuals at 

each life stage. These HRLs are calculated based on individuals who consume an average amount of 

perchlorate from food (except for pregnant women where EPA used a 90th percentile dietary intake 

estimate), but who consume equal or more water on a per body weight basis than 90 percent of their 

cohorts. 

EPA is evaluating these potential alternative HRLs and considers them to be levels of public health 

concern for purposes of this determination. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28872 

EPA Comment Code: 5100 

Comment: a) The SDWA requires that the contaminant must have an adverse effect on the health 

of persons. The weight-of-evidence, after examining the published scientific literature, demonstrates 

no documented adverse effects in humans exposed to perchlorate at environmental levels. 

Response: 

EPA disagrees. EPA disagrees that the “weight of evidence” demonstrates no documented adverse 

effects in humans exposed to perchlorate at environmental levels. See the final regulatory 
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determination for further discussion of the basis of EPA’s conclusion that perchlorate may have an 

adverse health effect on persons. 

EPA has determined that perchlorate meets SDWA’s criteria for regulating a contaminant —that is, 

perchlorate may have an adverse effect on the health of persons; perchlorate is known to occur or 

there is a substantial likelihood that perchlorate will occur in public water systems with a frequency 

and at levels of public health concern; and in the sole judgment of the Administrator, regulation of 

perchlorate in drinking water systems presents a meaningful opportunity for health risk reduction 

for persons served by public water systems. 

After careful review and consideration of public comments on the May 2007, October 2008, and 

August 2009 notices, and information available at this time, EPA has made this determination by 

comparing the best available data on the occurrence of perchlorate in PWSs to potential health 

reference levels (HRLs) for perchlorate as discussed in the regulatory determination final notice. 

Since the NRC also identified infants and developing children as additional life stages, EPA derived 

potential alternative HRLs for 14 life stages (age groups) using the RfD and life stage-specific 

exposure information in the August 9, 2009, notice (74 FR 41883; USEPA 2009b). These levels 

range from 1 μg/L to 47 μg/L and are the concentrations of perchlorate in drinking water that may 

result in total perchlorate exposures (from food and water) greater than the RfD for individuals at 

each life stage. These HRLs are calculated based on individuals who consume an average amount of 

perchlorate from food (except for pregnant women where EPA used a 90th percentile dietary intake 

estimate), but who consume equal or more water on a per body weight basis than 90 percent of their 

cohorts. 

EPA is evaluating these potential alternative HRLs and considers them to be levels of public health 

concern for purposes of this determination. 
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EPA Comment Code: 5200 SDWA Criterion #2 – EPA’s determination that 

perchlorate occurs infrequently at levels of health concern in public water 

systems 

Response to Code 5200: 

EPA has determined that perchlorate occurs or there is a substantial likelihood that perchlorate will 

occur with a frequency and at levels of health concern in public water systems. EPA has made this 

determination by comparing the best available data on the occurrence of perchlorate in PWSs to 

potential health reference levels (HRLs) for perchlorate. EPA collected and analyzed drinking water 

occurrence data for perchlorate from 3,865 PWSs between 2001 and 2005 under the UCMR 1. The 

minimum reporting level (MRL) for perchlorate under the UCMR 1 was 4 μg/L. EPA found that 

160 (approximately 4.1 percent) of the 3,865 PWSs that sampled and reported had at least 1 

analytical detection of perchlorate (in at least 1 sampling point) at levels greater than or equal to the 

MRL of 4 μg/L. These 160 PWSs are located in 26 States and 2 territories. Of these 160 PWSs, 8 are 

systems serving 10,000 or fewer people and 152 are systems serving more than 10,000 people. These 

160 systems reported 637 detections of perchlorate at levels greater than or equal to 4 μg/L, which 

is approximately 11.3 percent of the 5,629 samples collected by these 160 PWSs and approximately 

1.9 percent of the 34,331 samples collected by all 3,865 PWSs. The average concentration of 

perchlorate for those samples with positive detections for perchlorate was 9.85 μg/L and the median 

concentration was 6.40 μg/L. 

EPA derived potential alternative HRLs for 14 life stages (age groups) using the RfD and life stagespecific exposure information in the August 9, 2009, notice (74 FR 41883; USEPA 2009b). These 

levels range from 1 μg/L to 47 μg/L and are the concentrations of perchlorate in drinking water 

that may result in total perchlorate exposures (from food and water) greater than the RfD for 

individuals at each life stage. 

Based on percent of public water system estimates for perchlorate above thresholds of interest in 

Table 1 in the Federal Register Notice, and the range of potential alternative HRLs, EPA has 

determined that perchlorate is known to occur or there is a substantial likelihood that it will occur 

with a frequency and at levels of public health concern. 

In light of the discussion in this notice and the information available at this time, the Administrator 

finds that regulation of perchlorate in drinking water systems presents a meaningful opportunity for 

health risk reduction for persons served by public water systems. Therefore, EPA will initiate the 

process of proposing a NPDWR for perchlorate. 

Individual Comments 

Commenter Name: James Taft 

Commenter Organization: Association of State Drinking Water Administrators (ASDWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0169 

EPA Comment ID: 20286 

EPA Comment Code: 5200 

Comment: Perchlorate: 
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Based on state input, it does not appear that perchlorate is being detected in very many public water 

systems. Thus, while it may be a critical issue at a small number of water systems, it does not appear, 

at this stage, to be a nationwide problem that impacts most or all states. 

Response: See response to comment code 5200. 

Commenter Name: Melanie A. Marty, Ph.D. 

Commenter Organization: Children's Health Protection Advisory Committee 

EPA Document ID: EPA-HQ-OW-2008-0692-0962 

EPA Comment ID: 20422 

EPA Comment Code: 5200 

Comment: The second condition, that the contaminant occurs in public water supplies with a 

frequency and level of public health concern, is also met for perchlorate. The UCMR data show that 

millions of Americans are exposed to perchlorate in public supplies at concentrations greater than 6 

ug/L, the highest of three recently set state drinking water targets for perchlorate. The only way the 

second condition is not met is if an inappropriately high health benchmark is set. The CHPAC 

strongly feels that this is the case with USEPA's HRL of 15 ug/L as this would cause large numbers 

of infants to receive daily doses of perchlorate that are well above the Agency's RfD. 

Response: See response to comment code 5200. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection 

EPA Document ID: EPA-HQ-OW-2008-0692-1422 

EPA Comment ID: 20435 

EPA Comment Code: 5200 

Comment: 10. EPA Underestimates Numbers of At Risk Citizens. Due to the fact that MassDEP 

believes the HRL should be 2 ppb we conclude more than 16.6 million people are exposed to unsafe 

levels of perchlorate in their drinking water, and that this is a significant national public health issue. 

Response: Regarding your comment that EPA underestimated the number of people at risk, see 

response to comment code 5200. Regarding your comment that this is a significant national public 

health issue, EPA has determined that regulation of perchlorate in drinking water systems presents a 

meaningful opportunity to reduce health risk for persons served by public water systems. This action 

initiates the process to establish a national primary drinking water regulation for perchlorate 

including the maximum concentration of perchlorate that is allowed in public drinking water 

systems. 

Commenter Name: Michael Dourson 

Commenter Organization: Toxicology Excellence for Risk Assessment 

EPA Document ID: EPA-HQ-OW-2008-0692-1562 

EPA Comment ID: 20638 

EPA Comment Code: 5200 

Comment: Dear Sirs, 
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Based on EPA’s analysis of exposure data and relative source contribution, we agree that perchlorate 

is not occurring in the public water supply at levels that cause concern for health risks. 

Response: EPA disagrees with the commenter that the perchlorate is not occurring in the public 

water supply at levels that cause concern for health risks. See response to comment code 5200. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20907 

EPA Comment Code: 5200 

Comment: * Even EPA’s own flawed assessment finds that up to 2 million people may be exposed 

to perchlorate at levels that are of concern and yet, EPA chooses not to take any meaningful action. 

Response: EPA has determined that regulation of perchlorate in drinking water systems presents a 

meaningful opportunity to reduce health risk for persons served by public water systems. See 

response to comment code 6120. 

Commenter Name: Ron Curry 

Commenter Organization: New Mexico Environment Department 

EPA Document ID: EPA-HQ-OW-2008-0692-1796 

EPA Comment ID: 20937 

EPA Comment Code: 5200 

Comment: As to the second criterion, EPA estimates that 16,000 to 28,000 pregnant women would 

be exposed to perchlorate at levels exceeding the health reference level (HRL) of 15 "at any given 

time."[FN18: Id. at 60277.] EPA thus concludes that "perchlorate occurs infrequently at levels of 

health concern in public water systems."[FN19: Id.] EPA's analysis is seriously flawed for several 

reasons. 

First, the analysis fails to consider future health effects on women who have not yet become 

pregnant, and on their future fetuses. This failure is at odds with the plain language ofthe SDWA. 

Section 1412(b)(1)(A)(ii) requires EPA to consider not only whether a contaminant is known 

presently to occur in public water systems so as to cause public health concern, but also whether 

"there is a substantial likelihood that the contaminant will occur in public water systems with a 

frequency and at levels of public health concern."[FN20: 42 U.S.C. [section] 300g-1(b)(1)(A)(ii) 

(Westlaw 2008) (emphasis added).] Thus, Congress wisely directed EPA to consider potential future 

health effects in its analysis. But EPA has subtly avoided this consideration in its perchlorate 

analysis. EPA asks, "Is perchlorate known to occur or is there a substantial likelihood that 

perchlorate occurs at a frequency and at a level of public health concern in public water 

systems?"[FN21: 73 Fed. Reg. at 60275 (emphasis added).] EPA then answers this question in the 

negative because the agency finds that no more than 16,000 to 28,000 pregnant women "could be 

exposed at levels exceeding the HRL at any given time." EPA effectively takes a snapshot of 

perchlorate exposure at one instant in time. EPA does not take into account the millions of women 

who will become pregnant and who could be exposed to perchlorate above the HRL in future 

months, years, and decades. EPA's failure to account for future health effects is contrary to the 

SDWA. 
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Second, the analysis fails to consider health effects on infants. According to the National Research 

Council, infants comprise a subpopulation that is particularly sensitive to perchlorate exposure. For 

example, studies have shown that children with a mild iodide deficiency - which perchlorate can 

cause - have learning disabilities and perform less well on tests of mental and psychomotor 

ability.[FN22: NATIONAL RESEARCH COUNCIL, supra note 13, at 59.] Moreover, the HRL for 

infants is likely below the 15 ug/L that EPA determined for pregnant women.[FN23: See letter from 

Melanie A. Marty, Ph.D., Chair, Children's Health Protection Advisory Committee, to EPA 

Administrator Stephen L. Johnson, at 2 (Nov. 3, 2008).] EPA's failure to consider the adverse health 

effects of perchlorate ingestion on infants, a sensitive subgroup, in (preliminarily) determining that 

perchlorate occurs infrequently in public water systems at levels of health concern is also contrary to 

the SDWA. 

Third, the analysis fails to take into consideration health effects on persons with thyroid disorders. 

According to the National Research Council, people with thyroid disorders would be expected to be 

more sensitive to the effects of perchlorate ingestion.[FN24: NATIONAL RESEARCH 

COUNCIL, supra note 13, at 51.] Again, EPA's failure to consider the adverse health effects of 

perchlorate ingestion on persons with thyroid disorders in (preliminarily) determining that 

perchlorate occurs only infrequently in public water systems at levels of public health concern is 

contrary to the SDWA. 

Response: See response to comment code 5200. NRC specifies the fetus of a mother with 

hypothyroidism or iodine deficiency and low birthweight and premature infants as the most sensitive 

populations. Since the NRC also identified infants and developing children as additional life stages, 

EPA derived potential alternative HRLs for 14 life stages (age groups) using the RfD and life stagespecific exposure information in the August 9, 2009, notice (74 FR 41883; USEPA 2009b). These 

levels range from 1 μg/L to 47 μg/L and are the concentrations of perchlorate in drinking water 

that may result in total perchlorate exposures (from food and water) greater than the RfD for 

individuals at each life stage. These HRLs are calculated based on individuals who consume an 

average amount of perchlorate from food (except for pregnant women where EPA used a 90th

percentile dietary intake estimate), but who consume equal or more water on a per body weight basis 

than 90 percent of their cohorts. EPA is evaluating these potential alternative HRLs and considers 

them to be levels of public health concern for purposes of this determination. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-2082 

EPA Comment ID: 21028 

EPA Comment Code: 5200 

Comment: 11. Your letter asserts that millions are exposed to perchlorate at levels exceeding the 6 

μg/L, the highest of the state MCLs to be established. 

In our comments, the PSG has compared the risk opportunity from detects in public water systems 

(PWSs) between perchlorate and other compounds that EPA has decided not to regulate. The 

percentage of PWSs with perchlorate detections was very low (3.6 percent) compared to the next 

lowest unregulated compound, manganese at 68 percent. Sodium, for example, was detected in all 

PWSs. Perchlorate also has one of the lowest populations served by PWSs with detections above 
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half the HRL with 2.2 million people. Perchlorate is well within the range of values for the 

evaluation criterion EPA uses. 

Additionally, it bears repeating that EPA has incorporated an additional level of conservatism into 

an already conservative and health protective NAS-based RfD. Specifically, any exposures above the 

RfD, if they indeed occur, must first be considered in the context of a non-adverse effect. 

Response: Regarding the suggestion to compare the risk opportunity from detects in public water 

systems between perchlorate and other compounds that EPA has decided not to regulate, EPA does 

not believe it's appropriate to factor these comparisons into the decision whether to regulate a 

contaminant. The Administrator will make these determinations on a case-by-case, contaminant 

specific basis. In making a regulatory determination, the Administrator considers the adverse health 

effect of the particular contaminant at issue as well as the occurrence or likelihood of occurrence of 

the contaminant in public water systems with a frequency and at levels of public health concern. In 

addition, even if such a comparison were appropriate, perchlorate has, at least at the lower levels of 

public health concern identified, an occurrence that is substantially larger than most of the 

contaminants for which EPA has made a negative determination. Finally, it is the sole judgment of 

EPA’s Administrator to determine whether there is a meaningful opportunity to reduce health risk 

for persons served by public water systems. 

Regarding the comment that any exposures above the RfD must first be considered in the context 

of a non-adverse effect, the data underlying the definition of iodide uptake inhibition as a precursor 

effect and its relationship to the continuum of adverse thyroid outcomes reflects an understanding 

of effects in adults. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21096 

EPA Comment Code: 5200 

Comment: EPA's UCMR monitoring found a mean concentration of less than 10 ppb in systems 

with perchlorate - over 100 times lower than the NAS adverse effect level. Only a few systems have 

found any samples with concentrations greater than 100 ppb. Even the maximum level detected in 

the US is approximately 50 times lower than the dose at which the NAS panel determined adverse 

effects could begin. Specifically, the NAS panel noted that "...a sustained exposure of more than 0.4 

mg/kg per day would most likely be required to cause a sufficient decline in iodide uptake and 

thyroid hormone production to result in adverse health effects in normal adults." (NAS 2005) For 

these reasons, perchlorate is not known or likely to occur in public water systems with a frequency 

and at levels of public health concern. 

Response: See response to comment code 5200. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28873 

EPA Comment Code: 5200 
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Comment: b) The SDWA requires that the contaminant must be known to occur in PWSs with a 

frequency and at levels of public health concern. Where perchlorate is found, it is at levels often an 

order of magnitude below levels that cause IUI, itself a nonadverse effect. EPA data indicate average 

perchlorate concentrations in public drinking water systems are <10 parts per billion (ppb), and 99% 

of samples were <7 ppb. These levels are all below the equivalent concentration corresponding to 

the RfD, assuming a standard EPA default body weight and drinking water consumption rate, as 

well as the HRL of 15 ppb proposed by EPA in 2008 (U.S. EPA, 2008a). 

Response: See response to comment code 5200. 
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EPA Comment Code: 5210 Derivation of the RSC 

Response to Code 5210: EPA routinely applies a relative source contribution (RSC) to allow for 

the possibility that not all exposure will come from water, recognizing the importance of keeping the 

total exposure dose (e.g., water plus diet) below the RfD. 

EPA believes that use of an RSC for perchlorate is appropriate because the Greer et al. (2002) study, 

upon which the RfD is based, did not measure the levels of perchlorate in their food, and the 

sample size is small (37 healthy adults). 

The RSC is based on the best available peer reviewed science from the FDA (Total Diet Study) and 

estimates of exposure based on the NHANES/UCMR data which are robust evaluations of dietary 

exposure to perchlorate. A more detailed discussion of the derivation of the RSC can be found in 

the 2009 Federal Register Notice. 

Individual Comments 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0162 

EPA Comment ID: 20268 

EPA Comment Code: 5210 

Comment: In developing a drinking water regulation for perchlorate, EPA needs to address the 

Relative Source Contribution (RSC) for perchlorate in food and water. The proposal in the May 1st 

Federal Register notice is a starting point for making an appropriate RSC decision. AWWA 

recommends that EPA not adjust for RSC, since the subjects in the Greer study were exposed to 

background levels of perchlorate in addition to an experimental dose, as discussed on pg. 24046 of 

the May 1st Federal Register notice. 

Alternatively, if EPA doesn't accept the above recommendation, then EPA should derive the value 

of average daily rate of intake from background sources (ADRIB) from the mean (preferred 

approach) or upper tail (less preferred approach) of the NHANES data specific either to the entire 

sampled population or to individuals using bottled water. This background value should then be 

subtracted from the Reference Dose (RfD) and that result used to calculate the Drinking Water 

Equivalent Level (DWEL). This Modified ADRI approach better approximates the target average 

daily rate of intake (ADRI) that must be reached to ensure the RfD is not exceeded when water is 

added to the perchlorate contribution from all other sources combined (ADRIT). 

From a technical perspective, some of the options presentation in the May 1st Federal Register 

simply do not make sense. For example, the EPA option of a regression of the NHANES urinary 

data versus UCMR is not feasible and should not be considered. It would result in only a couple of 

dozen data points, an insufficient number to allow a meaningful regression. 

Appendix A [See Appendix A in PDF of docket ID EPA-HQ-OW-2007-0068-0162] to these 

comments is a report by Dr. Douglas Crawford- Brown of the University of North Carolina-Chapel 

Hill that was prepared on behalf of AWWA. Dr. Crawford- Brown’s report explains the above 
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recommendations in greater detail, comparing and contrasting alternative approaches to selecting a 

valid RSC value. We ask that his report be considered to be part of these comments. 

Response: See response to comment code 5210. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group (PSG) 

EPA Document ID: EPA-HQ-OW-2007-0068-0168 

EPA Comment ID: 20281 

EPA Comment Code: 5210 

Comment: BIOMONITORING DATA SUGGESTS THERE IS NO NEED TO ACCOUNT 

FOR PERCHLORATE EXPOSURES FROM OTHER SOURCES 

In the absence of extensive biomonitoring data, EPA has historically created an HRL by multiplying 

the Drinking Water Equivalent Level (DWEL) of the RfD by a Relative Source Contribution (RSC) 

for the constituent (a factor of the proportion of exposure expected to come from water). EPA’s 

Support Document outlines several options that EPA suggests for its RSC determination using the 

biomonitoring data and food surveys. If performed in a scientifically valid manner, the data shows 

that EPA would calculate an RSC of one (which yields an HRL of 24.5 ppb drinking water 

equivalent). 

EPA also references other approaches to calculate the RSC that appear to be at variance with the 

best available scientific information, representing overly conservative departures from customary 

EPA policy or apparently requiring months of additional computations. 

Ultimately, it appears that these approaches would yield essentially the same result: an RSC of one, 

which would render them duplicative. 

Attachment 3 [See PDF of docket ID EPA-HQ-OW-2007-0068-0168] provides detailed exploration 

of the issues raised in this section. Our analysis finds that proper application of the best available 

science through any of the Agencysuggested approaches will yield the same conclusion - perchlorate 

in drinking water is a small fraction of total exposure. Using the most reliable of the approaches 

EPA outlines, the RSC factor is essentially equal to one. 

Response: See response to comment code 5210. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20959 

EPA Comment Code: 5210 

Comment: Checking some outcomes from the current EPA HRL determination exercise 

-Apart from the above considerations, the EPA RSC derived from the FDA TDI study seems to 

correspond fairly well with the average perchlorate drinking water levels found in the U.S. 
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Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20961 

EPA Comment Code: 5210 

Comment: Additionally and apart from this, the EPA RSC has been checked against estimated 

average perchlorate dietary uptake via drinking water (section 3.1.) 

Also the EPA HRL has been checked against the HRL obtained the conventional way but with 

additional available data integrated (section 3.2.) 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20964 

EPA Comment Code: 5210 

Comment: 1.2. The dose-response trial set-up 

For clinical dose-response trials similar to the Greer trial, there are 3 possible trial set-ups. 

1.2.1. Trial set-up type 1 leading to RSC < 1 

The NOEL and therefore the RfD are based on a dose-response trial without food and without 

drinking water background level contribution. 

Or in other words the subjects that are administered the doses have a perchlorate free food diet and 

drink purified water. 

Therefore to arrive at the HRL the food background (FBG) level in the population will have to be 

estimated and subtracted from the RfD(which is based on the NOEL) . Therefore the RSC < 1 i.e. 

not all the RfD is attributed to DW. 

Example: 

Note: The examples are for illustrative purposes only. An UF of 4 is applied to allow smaller figures. 

NOEL1= 10ug/kg-day. RfD1 =2.5ug/kg-day 

The FBG contains 1.25 ug/kg-day (0.5 or 50% of RfD). Thus the part of the RfD attributed to DW 

is 0.5 RfD or 50 % of the RfD. 
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HRL1= maximum level of contaminant that DW should contain = [(RfD1 Ã— BW) /DWI] Ã— 

RSC=2.5 x70/2x0.5= 43.75 ppb. 

Fig.1: NOEL based on dose-response trial without perchlorate food /drinking water background: 

RSC [see PDF Docket ID EPA-HQ-OW-2008-0692-1798] 

1.2.2. Trial set-up type 2 leading to RSC=1 

The NOEL and therefore the RfD are based on a dose-response trial with food background (FGB) 

and without drinking water background (DWBG) level contribution. 

Or in other words the subjects that are administered the doses have a food diet with perchlorate 

background but drink purified water. 

Therefore to arrive at the HRL, the FBG level in the population is already included in the NOEL 

and thus does not have to be estimated and not subtracted from the RfD. Therefore RSC = 1 or 

100% i.e. all of the RfD is attributed to DW. 

The effective NOEL2 is larger than the dose NOEL1. 

Example: NOEL1 = 10ug/kg-day. FBG= 1.25 ug/kg-day. NOEL2 = NOEL1 + FBG=10 + 1.25 

= 11.25 ug/kg-day. 

RfD2 =1.125 ug/kg-day. 

The food diet background as mentioned has already been accounted for. 

The part of RfD2 attributed to water is 1 or 100 % of RfD2. 

HRL2 = [(RfD2Ã— BW) /DWI] Ã— RSC=1.125 x70/2x1 = 39.4 ppb. 

Or in other words, since NOEL1 is a dose added on top of the food background (see fig. 2) the 

whole RfD is attributed to DW. 

Fig. 2: NOEL based on dose-response trial with perchlorate food background and without drinking 

water background: RSC = 1 [see PDF Docket ID EPA-HQ- OW-2008-0692-1798] 

1.2.3. Trial set-up type 3: RSC is arithmetically >1 

The NOEL and therefore the RfD are based on a dose-response trial with food background and 

with drinking water background level contribution. 

Or in other words the subjects that are administered the doses have a food diet with perchlorate 

background and drink already contaminated water. 

Since the NOEL1 is added on top of the food background (see drawing), the whole RfD is 

attributed to DW. 
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Now, the DW background (DWBG) itself is on top of the NOEL1 .Therefore, arithmetically, the 

RSC must be <1. 

Example 1: NOEL1 = 10ug/kg-day. FBG= 1.25 ug/kg-day. DWBG = 0.625 ug/kg-day. NOEL3= 

NOEL1 + FBG +DWBG=10 + 1.25 +0.625 = 11.9 ug/kg-day. RfD3 =1.19 ug/kg-day. 

HRL3 = [(RfD2 +DWBG) Ã— BW)/DWI] Ã— RSC= [(RfD3 Ã— BW)/DWI] Ã— RSC= (1.19 

x70/2) x1 = 41.65 ppb. 

Example 2: Assume perchlorate 1.5 ppb DW background and NOEL2 =0.7 ug/kg-day. 

1.5 ppb background DW= 1.5 /70 x2= 0.04 ug/kg-day and HRL3 = (0.7+0.04) x 70 /2 x1 =26 ppb 

which arithmetically comes down to an RSC of 1.04 as 0.74x70/2 x 1.04= 26 ppb as well. 

Fig. 3: NOEL based on dose-response trial with perchlorate food background and with drinking 

water background: RSC > 1 [see PDF Docket ID EPA-HQ- OW-2008-0692-1798] 

More considerations about the RSC and practical examples can be found in: 

http://oehha.ca.gov/water/reports/howdsot.html. 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20972 

EPA Comment Code: 5210 

Comment: 3.1. RSC check 

If the contribution from food would be 10% (see EPAâ€TMs table 8) and which is derived from the 

TDS study model then of the 0.04 ug /kg-day total average perchlorate background exposure, 0.036 

ug /kg-day would come from water. 

Even, as already noted above, this is low compared to the other goitrogens, it would still translate 

into a US average drinking water content of 1.3 ppb (0.036 x70/2) which appears somewhat high 

but still close to EPAâ€TMs data on U.S. wide DW perchlorate levels. Therefore the TDS model may 

be an accurate enough tool to estimate RSCs. 

Response: See response to comment code 5120 for a discussion of the relative source contribution. 

Commenter Name: 

Commenter Organization: Ag Council et al 

EPA Document ID: EPA-HQ-OW-2008-0692-1987 

EPA Comment ID: 20977 

EPA Comment Code: 5210 
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Comment: EPA's Calculation of the Relative Source Contribution for its Preliminary 

Determination also Reveals that the Food Contribution is Below the Level of Concern. 

The US Centers for Disease Control’s National Health and Nutrition Examination Survey 

(NHANES) biomonitoring data provides a superior measure of actual human exposure to 

perchlorate from all sources, including food and water. FDA's TDS and food sampling data, which 

provides an approximation of human exposure to perchlorate from food, in fact validates EPA's 

calculation of the relative source contribution from food. 

Response: See response to comment ID 28919 under comment code 5210. 

Commenter Name: Kate Sande 

Commenter Organization: Minnesota Department of Health, Health Risk Assessment Section 

EPA Document ID: EPA-HQ-OW-2009-0297-0663 

EPA Comment ID: 28703 

EPA Comment Code: 5210 

Comment: Relative Source Contribution (RSC) MDH acknowledges the extensive national database 

of perchlorate exposure information that includes perchlorate concentrations found in food and 

beverages as well as biomonitoring data. We understand EPA's use of the NHANES biomonitoring 

data to estimate the 90th percentile food dose for pregnant women leading to the derivation of the 

drinking water RSC. For infants and young children, EPA states that the RSC is based on the central 

tendency dietary perchlorate exposure derived from FDA's Total Diet Study. MDH does wonder 

whether an RSC based on average dietary perchlorate exposure will protect individuals who have 

higher dietary doses. However, EPA's RSC for children 12- months and younger (0.59) based on the 

central tendency exposure is not much higher than the default RSC used by MDH for infants (0.5). 

MDH uses 0.2 as the relative source contribution (RSC) default value for volatile chemicals for all 

exposure durations. However, for non-volatile chemicals, an RSC of 0.5 is used for acute and shortterm exposure durations and 0.2 is used for subchronic and chronic exposure durations. 

Response: See response to comment code 5210. EPA believes that the central or mean estimates of 

dietary intake of perchlorate from the total diet study are the best available peer reviewed data for 

determining the relative source contribution. 

Commenter Name: Danielle Blacet 

Commenter Organization: Association of California Water Agencies 

EPA Document ID: EPA-HQ-OW-2009-0297-0208 

EPA Comment ID: 28919 

EPA Comment Code: 5210 

Comment: 2) Exposure from other sources 

The best evidence to date suggests that perchlorate is ubiquitous in the United States but UCMR 

data and other research suggest that little of this exposure is via drinking water. In addition, USEPA 

used the Greer et al study that used individuals who did not control or measure their exposure to 

perchlorate from food, a major source of perchlorate. This means that the ubiquitous background of 

perchlorate exposure found in the United States was built into the study, which was measuring the 
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effect of additional exposure above the background. This, along with the use of the no observed 

effect level (NOEL) versus no observed adverse effect level (NOAEL), actually makes the study 

more robust and has additional protection built into it. When the USEPA later uses uncertainty 

factors in their review, they are double-counting those factors. 

The use of a relative source contribution (RSC) does not appear to be warranted in this situation. 

Given the very small contribution to perchlorate exposure from drinking water, the precedent set by 

USEPA when they evaluated sodium was that the RSC should be ignored. It is also important to 

note that other more dominant goitrogens have much greater occurrence than perchlorate in 

drinking water. 

Response: See response to comment code 5210 for a discussion of the RSC. 

EPA does not believe the conditions for the sodium regulatory determination are comparable to 

those for perchlorate. Dietary exposure alone does not exceed the reference dose; however, for 

some people in water systems with perchlorate contamination the dietary exposure combined with 

drinking water exposure may result in a total dose that exceeds the RfD for perchlorate. This is of 

particular concern among sensitive life stages. 

Commenter Name: Kay Brothers 

Commenter Organization: Southern Nevada Water Authority 

EPA Document ID: EPA-HQ-OW-2009-0297-0667 

EPA Comment ID: 29076 

EPA Comment Code: 5210 

Comment: Furthermore, based upon available epidemiological and other human studies, the use of 

RSC is inappropriate. For these reasons, it is unlikely that modeling a compound known to form 

naturally and occur ubiquitously represents an appropriate representation of actual conditions. 

Response: See response to comment code 5210. 
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EPA Comment Code: 5220 Derivation of the HRL 

Response to Code 5220: EPA has reversed its October 2008 preliminary determination not to 

develop an NPDWR for perchlorate and now concludes, based on the analysis presented in today’s 

notice, that perchlorate meets the criteria for regulating a contaminant in Section 1412(b)(1)(A) of 

SDWA. EPA has found that 1.) perchlorate may have an adverse effect on the health of persons; 2) 

perchlorate is known to occur or there is a substantial likelihood that perchlorate will occur in public 

water systems with a frequency and at levels of public health concern; and 3) in the sole judgment of 

the Administrator, regulation of perchlorate in drinking water systems presents a meaningful 

opportunity for health risk reduction for persons served by public water systems. In proposing a 

national primary drinking water standard, EPA will seek public comments on the proposed standard, 

and analyses on which it is based, pursuant to SDWA requirements. 

EPA has made this determination by comparing the best available data on the occurrence of 

perchlorate in PWSs to potential health reference levels (HRLs) for perchlorate. HRLs are not final 

determinations about the level of a contaminant in drinking water that is necessary to protect any 

particular population. Rather they are benchmarks against which EPA compares the concentration 

of a contaminant found in public water systems to determine if it is at levels of public health 

concern. 

In the October 2008 preliminary regulatory determination, EPA had derived a single HRL of 15 

μg/L based upon the RfD, an estimate of perchlorate exposure from food for pregnant women, and 

traditional adult body weight (70 kg) and drinking water consumption (2 L/day) values. This single 

HRL was derived to reflect exposure to a pregnant woman and her fetus, which the NRC identified 

as “the most sensitive population.” 

Since the NRC also identified infants and developing children as additional life stages, EPA derived 

potential alternative HRLs for 14 life stages (age groups) using the RfD and life stage-specific 

exposure information in the August 9, 2009, notice (74 FR 41883; USEPA 2009b). These levels 

range from 1 μg/L to 47 μg/L and are the concentrations of perchlorate in drinking water that may 

result in total perchlorate exposures (from food and water) greater than the RfD for individuals at 

each life stage. These HRLs are calculated based on individuals who consume an average amount of 

perchlorate from food (except for pregnant women where EPA used a 90th percentile dietary intake 

estimate), but who consume equal or more water on a per body weight basis than 90 percent of their 

cohorts. 

EPA is evaluating these potential alternative HRLs and considers them to be levels of public health 

concern for purposes of this determination. EPA has compared these values to the data provided by 

PWSs subject to the first Unregulated Contaminant Monitoring Rule (UCMR 1). EPA collected and 

analyzed drinking water occurrence data for perchlorate from 3,865 PWSs between 2001 and 2005 

under the UCMR 1. The minimum reporting level (MRL) for perchlorate under the UCMR 1 was 4 

μg/L. 

EPA found that 160 (approximately 4.1 percent) of the 3,865 PWSs that sampled and reported had 

at least 1 analytical detection of perchlorate (in at least 1 sampling point) at levels greater than or 

equal to the MRL of 4 μg/L. Table 1 of today's notice presents the number and percentage of PWSs 
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that reported perchlorate at levels exceeding various threshold concentrations. Note that the MRL 

for perchlorate under the UCMR 1 was 4 μg/L. 

Given the range of potential alternative HRLs, EPA has reversed its October 2008 preliminary 

determination not to regulate perchlorate in drinking water. Based on the data in Table 1 and the 

range of potential alternative HRLs, EPA has determined that perchlorate is known to occur or 

there is a substantial likelihood that it will occur with a frequency and at levels of public health 

concern. 

Table 2 of today’s notice presents EPA’s estimates of the population served by PWSs that were 

monitored under UCMR 1 for which the highest reported perchlorate concentration was greater 

than the thresholds identified in Table 1. These population estimates are for people at all life stages. 

EPA has determined that a NPDWR for perchlorate could reduce perchlorate exposures for these 

populations to levels below the potential alternative HRLs that EPA has identified as levels of public 

health concerns for purposes of this determination, and that such exposure reductions present a 

meaningful opportunity for the reduction of health risks for persons served by PWSs. 

Individual Comments 

Commenter Name: Apparent Mass Mailing #2 - Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0100 

EPA Comment ID: 19690 

EPA Comment Code: 5220 

 

Comment: The maximum safe level for perchlorate in drinking water is now 15 times higher than 

what the EPA declared safe in 2002. Under this new standard, more than 16 million Americans are 

exposed to unsafe levels of perchlorate in their drinking water, and independent analysis shows 

anywhere from 20 to 40 million Americans at risk. Perchlorate has been found in the drinking water 

in 35 states in the U.S. 

Response: See response to comment ID 19873 under comment code 5220. 

Commenter Name: Apparent Mass Mailing #2 - Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0100 

EPA Comment ID: 19690 

EPA Comment Code: 5220 

 

Comment: The maximum safe level for perchlorate in drinking water is now 15 times higher than 

what the EPA declared safe in 2002. Under this new standard, more than 16 million Americans are 

exposed to unsafe levels of perchlorate in their drinking water, and independent analysis shows 

anywhere from 20 to 40 million Americans at risk. Perchlorate has been found in the drinking water 

in 35 states in the U.S. 

Response: See response to comment ID 19873 under comment code 5220. 

Commenter Name: A. Lane 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0276 

EPA Comment ID: 19781 
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EPA Comment Code: 5220 

 

Comment: According to the EPA’s own data, 16 million Americans are at risk of being exposed to 

Perchlorate. The maximum safe level for perchlorate in drinking water is now 15 times higher than 

what the EPA declared safe in 2002. 

Response: See response to comment ID 19873 under comment code 5220. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0422 

EPA Comment ID: 19873 

EPA Comment Code: 5220 

 

Comment: Please follow our own Environmental Protection Agency's recommendations for levels 

of perchlorate allowed in drinking water, set in 2002. Thank you. 

Response: EPA's 2002 draft risk assessment was revised based upon the 2005 National Research 

Council's (NRC) recommendations. EPA has developed potential health reference levels (HRLs) for 

perchlorate for purposes of this regulatory determination. HRLs are not final determinations about 

the level of a contaminant in drinking water that is necessary to protect any particular population. 

Rather they are benchmarks against which EPA compares the concentration of a contaminant found 

in public water systems to determine if it is at levels of public health concern. 

See response to comment codes 5220 and 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0475 

EPA Comment ID: 19903 

EPA Comment Code: 5220 

 

Comment: The maximum safe level for perchlorate in drinking water is now 15 times higher than 

what the EPA declared safe in 2002. Under this new standard, more than 16 million Americans are 

exposed to unsafe levels of perchlorate in their drinking water, and independent analysis shows 

anywhere from 20 to 40 million Americans at risk. Perchlorate has been found in the drinking water 

in 35 states in the U.S. 

Response: See response to comment ID 19873 under comment code 5220. 

Commenter Name: S. G. Gompf 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0490 

EPA Comment ID: 19911 

EPA Comment Code: 5220 

 

Comment: Since 2002, the EPA's maximum safe level for perchlorate in drinking water raised 15-

fold! Why was the bar lowered? As an American mother and a physician, I have to question why the 
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EPA appears to be acting against the interests of its constituents in thismatter, and whether the EPA 

is acting in the interest of hidden benefactors in industry. 

Response: See response to comment ID 19873 under comment code 5220. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0493 

EPA Comment ID: 19915 

EPA Comment Code: 5220 

 

Comment: Millions of Americans in over 35 states are exposed to this chemical as maximum safe 

level for perchlorate in drinking water is now 15 times higher than what the EPA declared safe in 

2002. PSR 2008. 

Response: See response to comment ID 19873 under comment code 5220. 

Commenter Name: A. L. Segall 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0506 

EPA Comment ID: 19926 

EPA Comment Code: 5220 

 

Comment: I understand that the amount of perchlorate in our drinking water is now 15 times the 

amount that the government determined was safe in 2002. It seems clear that we should not allow 

such a large amount of this chemical to be in our drinking water. 

Response: See response to comment ID 19873 under comment code 5220. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0525 

EPA Comment ID: 19938 

EPA Comment Code: 5220 

 

Comment: Please renew the 2002 EPA Standards concerning Perchlorate. It is in the Nations best 

interest. 

Response: See response to comment ID 19873 under comment code 5220. 

Commenter Name: K. Peterson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0646 

EPA Comment ID: 19989 

EPA Comment Code: 5220 

 

Comment: It is unacceptable that the maximum safe level for perchlorate in drinking water is now 

15 times higher than what the EPA declared safe in 2002. How does that happen? This is a huge 
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defeat for the environment and for public health; it would be laughable if it wasn't such a serious 

issue. 

As the Environmental Protection Agency, you are supposed to be protecting the environment and 

public health. If you are going to raise your "maximum safe level" for perchlorate, why don't you 

just go ahead and change your name to the Chemical Companies' Protection Agency? That would be 

a much more suitable monkier for the actions you are taking. 

Response: See response to comment ID 19873 under comment code 5220. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group (PSG) 

EPA Document ID: EPA-HQ-OW-2007-0068-0168 

EPA Comment ID: 20279 

EPA Comment Code: 5220 

 

Comment: REVIEW OF THE NAS REPORT AND SUBSEQUENT PEER-REVIEWED 

STUDIES AFFIRMS USE OF THE RfD AS THE HEALTH REFERENCE LEVEL 

EPA must often make important decisions on the basis of less information than it would wish; and 

perchlorate is a welcome exception. 

There is extensive scientific literature, most notably a comprehensive, authoritative review of the 

range of peer-reviewed studies by the National Research Council of the National Academy of 

Sciences (NAS). The success of EPA, along with other agencies, in obtaining this review has put the 

Agency in an unusually well-informed position, backed by the deliberations and judgment of the 

nation’s highest scientific body. The NAS Report, followed by the Agency’s own RfD process, is 

supplemented by subsequent, peer-reviewed studies. Taken together, these comprise a solid basis for 

an EPA regulatory determination. 

EPA’s RfD is the best health benchmark to use as the health reference level (HRL). EPA concurred 

with the conclusion of the NAS panel in the adoption of the panel’s recommendation as EPA’s 

RfD. This RfD is based on the NAS panel’s emphatically conservative approach of establishing the 

point of departure at the No Observed Effect Level (NOEL), rather than EPA’s customary No 

Observed Adverse Effect Level (NOAEL). Consistent with EPA’s design for RfDs, the NAS panel 

selected its recommended RfD to be protective of all sensitive populations. Subsequent peerreviewed studies affirm and reinforce the conclusion that the RfD is a conservative, health 

protective value that protects all members of society, even the most sensitive population. 

Further discussion of these studies and our comments is contained in Attachment 1 [See PDF of 

docket ID EPA-HQ-OW-2007-0068-0168]. 

Response: EPA is utilizing the RfD to derive potential alternative health reference levels and 

evaluate the opportunity for health risk reduction through a drinking water regulation for 

perchlorate. See response to comment code 5220. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection 
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EPA Document ID: EPA-HQ-OW-2008-0692-1422 

EPA Comment ID: 20431 

EPA Comment Code: 5220 

 

Comment: 2. EPA’s HRL Is Not Sufficiently Health Protective. MassDEP continues to believe that 

EPA’s Reference Dose (RfD) and the associated Health Reference evel (HRL) for drinking water for 

perchlorate are insufficiently health protective of neonatal exposures. There is compelling evidence 

to support a national drinking water standard for perchlorate at a value well below EPA’s HRL of 15 

ppb. 

* Literature publications (Zoeller and Rice, 2004; Zoeller, 2006; Ginsberg et al., 2007) and state 

agency risk assessments (MassDEP, 2006; CA, 2004) support a more health protective RfD and 

drinking water value. EPA’s HRL of 15 ppb is 7.5 times higher than MassDEP’s drinking water 

standard of 2 ppb and 2.5 times higher than California’s standard of 6 ppb. EPA’s evaluation 

includes no discussion of these alternative assessments. * The results of Blount et al (2006) and 

Steinmaus et al (2007) demonstrate thyroid effects associated with a dose of 0.06 ug/kg/day in 

iodide insufficient women, which is well below, and calls into question the protectiveness of, EPA’s 

RfD of 0.7 ug/kg/day. * Although acknowledged in EPA’s evaluation, potential interactive effects 

between thiocyanate, a metabolite of cyanide found in tobacco smoke and some common foods, 

and perchlorate, were not accounted for. Such interactions heighten concern regarding perchlorate 

induced thyroid hormone effects in women with serum iodine levels < 100 ug/L. * Use of a more 

appropriate and health protective RfD would lower the acceptable drinking water limit for 

perchlorate, resulting in a substantial increase in the total number of citizens exposed to 

unacceptably high levels of this toxicant from drinking water. This would clearly create a 

"meaningful opportunity for health risk reduction" through a national perchlorate drinking water 

regulation under the Safe Water Drinking Act. 

Response: See response to comment code 5220. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection 

EPA Document ID: EPA-HQ-OW-2008-0692-1422 

EPA Comment ID: 20432 

EPA Comment Code: 5220 

 

Comment: 3. Infant Exposures at the HRL Exceed EPA’s Insufficiently Protective RfD. EPA’s 

calculations (Table 8, Federal Register publication) demonstrate that perchlorate intake by nursing 

and bottle-fed infants and children to 2 years of age, attributable to the consumption of drinking 

water at 15 ug/L (and not even considering other dietary sources of exposure) would substantially 

exceed EPA’s insufficiently health protective RfD value. Based on EPA’s own calculations, a bottlefed infant would receive a dose of perchlorate 5 times higher than EPA’s RfD and 50 times higher 

than MassDEP’s RfD. Consistent with EPA’s assessment, in a study conducted in Texas Dasgupta 

et al. (2008) also showed that the majority the infants (9 out 13 infants) in their study ingested 

perchlorate at a level that exceeds the EPA reference dose. Furthermore, this study indicates that 

breast milk iodide concentrations decrease as perchlorate levels increase in breast milk (Dasgupta et 

al., 2008), potentially raising risks to nursing infants. Due to potential impacts on children’s health, 

this data alone justifies the establishment of a lower, more appropriately health protective HRL for 

perchlorate. By discounting this information in the evaluation, EPA is de facto adopting an even 
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higher, less protective RfD for these sensitive subgroups. EPA’s explanation for discounting these 

findings- that the model’s predicted iodide uptake inhibition (IUI) level at 15 ppb would be 

insignificant- is unjustified for at least three reasons. 

a. The predicted IUI in these groups is very uncertain due to model limitations. 

b. Although EPA indicates that iodide uptake inhibition of 2.2% is non- adverse, no objective data 

exists to support this determination and no objective safe level of IUI, especially in the neonate, has 

been established. In fact, the Blount et al. (2006) and Steinamus et al. (2007) studies indicate that 2.6 

ug/L of urinary perchlorate (which equates to an approximate dose level of 0.06 ug/kg/d in iodine 

deficient women was associated with decreased T4 and increased TSH levels, consistent with the 

mode of action of perchlorate. Iodide uptake inhibition at this dose level would be predicted by the 

model to be very small suggesting either that the model is inaccurate; the effect is not solely due to 

IUI or low levels of IUI are adverse. 

c. Allowing up to 2.2% iodine uptake inhibition also exceeds NRC’s hypothesized non-adverse 

effect level of 1.8% IUI (NRC, 2005) although 1.8% IUI is considered an adverse effect level by 

many scientists (US EPA 2002; Ginsberg and Rice, 2005; and MassDEP, 2006). 

Response: See response to comment code 5220 for a discussion of the alternative Health Reference 

Levels. Regarding the predictions of iodide uptake inhibition Physiologically-Based Pharmacokinetic 

(PBPK) Modeling , EPA reviewed, modified, and applied the perchlorate PBPK models, which 

were originally developed by Merrill et al. (2005) for adults and Clewell et al. (2007) for other life 

stages, to estimate the iodide uptake inhibition in the thyroid for each life-stage (73 FR 60262; 

USEPA 2008a). Estimated ingestion rates were then used to estimate the internal dose and resulting 

iodide uptake inhibition for several life stages, including susceptible populations (e.g., pregnant 

women and their fetuses, as well as breast-fed and bottle-fed infants). 

In the August 2009 notice, EPA stated that it was re-evaluating how best to incorporate the PBPK 

modeling analysis into its evaluation of perchlorate- if at all. The Agency sought comments on ways 

to use the PBPK modeling analysis to inform the regulatory determination. 

Several commenters support the use of the PBPK model to inform the regulatory determination 

only if the significant limitations of the current model are addressed. For example, the inability of 

the model to reflect iodide nutritional status was cited by commenters and three of the four peer 

reviewers as an important limitation. Also, several commenters stated that the risks to breast-fed 

infants and young children are not adequately addressed. They challenged that the modeling analysis 

is based on average weight infants and healthy adults, while the sensitive life stages for perchlorate 

include premature infants and hypothyroid women. 

After further consideration of the peer review and public comments, EPA concludes that the PBPK 

modeling analysis, in the context of the perchlorate regulatory determination, is useful in examining 

which life stages are most susceptible to the effects of perchlorate. For example, the model indicates 

that a fetus may be seven times more sensitive to the effects of perchlorate than a pregnant woman. 

The model also allows for the estimation of the concentration of perchlorate in breast milk (thus 

breast-fed infant exposure) at various maternal perchlorate exposure levels. However, because of the 

stated limitations, EPA has decided the model does not directly bear on the current decision 
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regarding the need for a NPDWR for perchlorate. EPA is continuing to evaluate whether the model 

could be used in setting a NPDWR for perchlorate. 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Dept. of Environmental Protection 

EPA Document ID: EPA-HQ-OW-2008-0692-1526 

EPA Comment ID: 20449 

EPA Comment Code: 5220 

 

Comment: Further, it is our opinion that the information provided in the proposal indicates that 15 

ug/L is not a health protective drinking water concentration, and that the HRL should be set at a 

lower level that is protective of public health for all exposed subpopulations. A primary concern is 

that the exposure and health risks of bottle-fed infants, as predicted by the PBPK model, are 

ignored in the proposal. The PBPK model predicts that when the perchlorate concentration in water 

used to prepare formula is 15 ug/L, 7-day and 60-day old bottle-fed infants are exposed to more 

than 5 times the RfD, and that iodide uptake in 7-day old infants is decreased by 2.2% (Table 8). 

Even if the model were to use the median rather than the 90th percentile water intake, the RfD 

would be greatly exceeded. The model also predicts that a breast-fed infant would be exposed to 

more than twice the RfD from perchlorate in the mother’s milk due to maternal ingestion of water 

contaminated with 15 ug/L perchlorate. The weaned 6-12 month old is predicted to be exposed to 

almost 3 times the RfD when water with 15 ug/L perchlorate is used to prepare fluids and foods. 

Response: See response to comment code 5220 and response to comment ID 20432 under 

comment code 5220. 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Dept. of Environmental Protection 

EPA Document ID: EPA-HQ-OW-2008-0692-1526 

EPA Comment ID: 20451 

EPA Comment Code: 5220 

 

Comment: Decision not to regulate perchlorate based on population exposed above the HRL 

The estimation of the number of people exposed to perchlorate at a level of public health concern in 

public drinking water is determined by the perchlorate concentration chosen as the HRL. Setting an 

HRL at an inappropriately high concentration, 15 ug/L, greatly reduces the size of the population 

predicted to be exposed at a level of public health concern. Table 2 of the proposal shows that 

approximately 2 million people (in 0.8% of systems) or, alternatively, an estimated 0.9 million people 

served by 0.29% of points-of-entry (POEs) are exposed at or above an HRL of 15 ug/L. USEPA 

states that this number of people is not sufficient to warrant regulation. However, if the level were 

to be set at 5 ug/L, for example (a concentration that still would result in bottle-fed infants being 

exposed slightly above the Reference Dose, based on the exposure assumptions in Table 8), 5 to 7 

times more individuals would be exposed above the HRL than at 15 ug/L: 14.6 million people 

(3.2% of systems) or 4 million people served by 1.9% of POEs would be exposed above 5 ug/L. 

Therefore, by setting the drinking water concentration higher than it should be from a health 

viewpoint, USEPA has also significantly minimized the need for regulation of perchlorate from an 

occurrence viewpoint. 
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Response: See response to comment code 5220. 

Commenter Name: Gregg Grunenfelder 

Commenter Organization: Washington State Department of Health; and Oregon Department of 

Human Services 

EPA Document ID: EPA-HQ-OW-2008-0692-1529 

EPA Comment ID: 20459 

EPA Comment Code: 5220 

 

Comment: * Roughly, 17% of reproductive-aged women in the United States are especially 

susceptible to perchlorate toxicity due to inadequate dietary intake of iodine and are susceptible to 

hypothyroxinemia and hypothyroisism during pregnancy. There is a possibility that some women in 

the child-bearing age in the United States are getting less than the recommended daily iodide intake 

level. 

* Iodine deficiency during early pregnancy may cause irreversible neurodevelopmental deficits in 

offspring. 

* Exposure to perchlorate is likely to further reduce iodide uptake by the thyroid. 

* As many as 350,000 pregnant women within the United States may be exposed at any given time 

to perchlorate levels considered unsafe. 

Because there is uncertainty regarding our understanding of perchlorate toxicity, exposure, and 

presence in the environment, a cautious approach for protecting sensitive populations should be 

taken. The department concludes that EPA’s health reference level is not adequately protective of 

the health of sensitive subpopulations and the determination that a meaningful opportunity for risk 

reduction through the regulation of perchlorate in drinking water is not supported from a public 

health perspective. 

Response: See response to comment code 5220. 

Commenter Name: Denise F. Sipple 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1621 

EPA Comment ID: 20548 

EPA Comment Code: 5220 

 

Comment: Many experts disagree with your assessment that drinking water with 15 parts per billion 

of perchlorate is safe and acceptable. Scientists from the California Environmental Protection 

Agency and the Massachusetts Department of Environmental Protection have set stricter standards 

to will ensure that the most vulnerable populations -- pregnant women, infants, and small children -- 

are protected from the adverse impacts of perchlorate. 

EPA's analysis fails to consider that the combination of food and drinking water exposure to 

perchlorate in the U.S. population exceeds the reference dose set by EPA. Nor does it incorporate 

the more protective methodology behind the recent state regulatory actions. These flaws must be 
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remedied for the sake of the millions of U.S. families exposed to dangerous levels of perchlorate 

contamination. 

Thank you and God Bless. 

Response: See response to comment code 5220. 

Commenter Name: Dick Wilson 

Commenter Organization: Anaheim Public Utilities Department 

EPA Document ID: EPA-HQ-OW-2008-0692-1530 

EPA Comment ID: 20556 

EPA Comment Code: 5220 

 

Comment: Dear US EPA, 

As a community water system in the State of California, Anaheim Public Utilities believes that 

continuing the process for establishing a drinking water standard for perchlorate would fall well 

within SDWA guidelines. Although the Preliminary Regulatory Determination on Perchlorate finds 

that a health reference level of 15 ug/l appears to be a reasonable estimate for a potential drinking 

water standard, the States of California and Massachusetts have established drinking water standards 

for perchlorate at much lower levels. Therefore, we conclude that there is ample evidence that the 

actual level of public health concern for perchlorate is truly much lower than the health reference 

level mentioned in the Preliminary Regulatory Determination. 

Thank you for your consideration of this comment. Sincerely, 

Dick Wilson Environmental Services Manager Anaheim Public Utilities Department 714-765-4277 

dwilson@anaheim.net 

Response: See response to comment code 5220. 

Commenter Name: Robert Howd 

Commenter Organization: California Environmental Protection Agency, Water Toxicology 

Section 

EPA Document ID: EPA-HQ-OW-2008-0692-1671 

EPA Comment ID: 20648 

EPA Comment Code: 5220 

 

Comment: IV (B), p 60275. The formula used to calculate the health risk level for perchlorate uses 

the default body weight for an adult male, and default drinking water consumption of 2 L/day. 

Recent EPA exposure assessment guidance (U.S. EPA, 2004) recommends using exposure data 

more relevant to the actual persons at risk. OEHHA has accepted that guidance in its risk 

assessments and is disappointed that EPA itself has not. Specifically, since the greatest risk of 

exposure to perchlorate appears to be in pregnant women and in infants, we believe that body 

weights and drinking water consumption values which are fully protective of these groups should be 

utilized in this risk assessment. The upper 95th percentile drinking water consumption rates appear 

to us to be adequately protective. Applying this health-protective value to the EPA reference dose of 

0.7 ug/kg-day and relative source contribution of 0.62 yields the following: 
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Pregnant women: (0.0007 mg/kg-day x 0.62) / 0.055 L/kg-day = 0.008 mg/L 

For infants, the comparable calculation is more complicated, because the reference dose of 0.7 

ug/kg-day was calculated for an adult, as was the relative source contribution. However, if those 

values were retained, the following result is obtained: 

Infants: (0.0007 mg/kg-day x 0.62) / 0.221 L/kg-day = 0.002 mg/L 

If the starting point for calculation of the RfD were the BMDL of 0.0037 mg/kg- day, these 

numbers would be correspondingly lower, although again, a health- protective dose and relative 

source contribution for infants should be calculated separately. It seems to us that numbers in this 

range should be being used in making the decision whether or not to regulate perchlorate in drinking 

water. 

IV (B)(3), p 60277. Table 7, Health Reference Levels for Pregnant Women. We are concerned that 

EPA continues to use the obsolete default values of 70 kg for body weight and 2 L/day of water 

consumption when these values certainly do not apply to pregnant women. These defaults are 

specifically intended for the population in general, and should be superseded by more specific and 

appropriate values when a risk assessment is being conducted for a defined subpopulation (U.S. 

EPA, 2004, 2005). 

Response: See response to comment code 5220. 

Commenter Name: Tim Cranford 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1896 

EPA Comment ID: 20781 

EPA Comment Code: 5220 

 

Comment: Perchlorate has been linked to thyroid problems in vulnerable segments of our 

population, such as newborns, pregnant women and young children. The current "safe" levels of this 

chemical for drinking water is now set at some 15 times higher than was set in 2002. 

Response: See response to comment ID 19873 under comment code 5220. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1983 

EPA Comment ID: 20821 

EPA Comment Code: 5220 

 

Comment: The facts are that the maximum safe level for perchlorate in drinking water is now 15 

times higher than what was declared safe in 2002. Under this new standard, more than 16 million 

Americans are exposed to unsafe levels of perchlorate in their drinking water, and independent 

analysis shows anywhere from 20 to 40 million Americans at risk. Perchlorate has been found in the 

drinking water in 35 states in the U.S. 
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Response: See response to comment ID 19873 under comment code 5220. 

Commenter Name: Lee Walsh 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1997 

EPA Comment ID: 20832 

EPA Comment Code: 5220 

 

Comment: It is absolutely outrageous that the allowable level of known toxin Perchlorate be 

increased by 1500% in the drinking water of the American people. At what benefit? What purpose 

can this possibly serve, to deliberately poison our own people? 

Lee Walsh Albuquerque, NM 

Response: See response to comment ID 19873 under comment code 5220. 

Commenter Name: Mary Moore 

Commenter Organization: Lindon Park Neighborhood Association (LPNA) 

EPA Document ID: EPA-HQ-OW-2008-0692-2002 

EPA Comment ID: 20834 

EPA Comment Code: 5220 

 

Comment: A more thorough investigation of the potential impact of perchorlate on fetuses, 

children and women seems appropriate. Even the model currently employed by EPA appears to 

propose a health reference level that exposes young children to perchlorate levels above the 

reference dose. 

Response: See response to comment code 5220. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20915 

EPA Comment Code: 5220 

 

Comment: EPA’s flawed assessment still finds that millions of people are exposed to potentially 

harmful levels of perchlorate: EPA’s assessment is fundamentally flawed for the reasons described 

above. In this assessment, EPA determines that 15 ug/L (15 ppb) is an appropriate health reference 

level (HRL); this number was arrived at, in part, by using data from the unpublished study that was 

just described in the preceding section of this document. It should be noted that in the Blount study, 

women with lower iodine levels who had exposure to perchlorate in drinking water as low as 2 ppb 

had an associated 11% decrease in thyroid hormone levels (Blount et al. 2006b). It is clear that the 

EPA HRL is not protective of public health since levels of perchlorate exposure far below 15 ug/L 

result in significant changes in thyroid hormone levels. 

Response: See response to comment code 5220. 

Commenter Name: Caroline Baier-Anderson, PhD 
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Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20951 

EPA Comment Code: 5220 

 

Comment: EPA concludes that a health risk level (HRL) of 15 ug/L would be adequate to protect 

public health. We strongly disagree. As documented in the previous sections, the HRL is based on a 

flawed reference dose, and does not adequately take into account either the role of individual 

variability or iodine status factors that recent studies have demonstrated play a critical role in 

determining an individual's response to perchlorate. When combined with what is known about the 

biology of thyroid homeostasis and the increased sensitivity of the fetus and neonate, it is clear that 

the HRL will not adequately protect sensitive subpopulations in the US. 

Response: See response to comment code 5220. 

Commenter Name: Caroline Baier-Anderson, PhD 

Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20953 

EPA Comment Code: 5220 

 

Comment: Determining the number of facilities where perchlorate concentrations exceed a healthprotective level depends on the selection of a health-protective level; as a result of this circular logic, 

if the health risk level is under- protective, then a smaller number of facilities will be identified. A 

lower, more protective health risk level will identify a larger number of facilities, and therefore 

exposed individual. As we have documented in the previous sections, the health risk level selected 

by EPA is not adequate to protect sensitive subpopulations. Hence, EPA underestimates the 

number of facilities that are supplying perchlorate-contaminated drinking water. 

Response: See response to comment code 5220. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20956 

EPA Comment Code: 5220 

 

Comment: Summary 

1. When to apply a RSC and when not 

Applying a RSC when determining the HRL for perchlorate is not justified as the NOEL found thru 

the clinical dose-response trial on which the HRL is based already incorporates a RSC thru the 

background level that was present. 

Response: See response to comment code 5210. 

Commenter Name: Herwig Opdebeeck 
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Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20958 

EPA Comment Code: 5220 

 

Comment: -Consequently, to be health protective, a joint DW HRL of nitrate and perchlorate of 45 

ppb total perchlorate equivalent should be proposed. 

-If for nitrate the same UF=10 would be applied as for perchlorate, the HRL for perchlorate alone, 

after subtraction of this adjusted nitrate MCL would be 26.7 ppb which is close to the 27 ppb 

derived from the total perchlorate equivalent RfD when attributing a 40% share of nitrate plus 

thiocyanate in this goitrogenic background conform with the NHANES data. It is also close to the 

current EPA DWEL of 24.5 ppb. 

Consequently those 2 alternative data based approaches seem to confirm once more the NRS RfD 

and the current EPA DWEL based on a RSC of 1. 

Response: While EPA acknowledges that nitrate and thiocyanate have the same mode of action as 

perchlorate, and that the effects of combined exposure to perchlorate, nitrate, and thiocyanate are 

additive, EPA does not believe there are sufficient scientific data currently available to assess and 

characterize the combined risk of these contaminants. EPA has committed to a drinking water 

strategy that outlines four principles to expand public health protection for drinking water (USEPA, 

2010b). One of these principles is to address contaminants as groups. However, EPA does not 

believe that regulatory action to address perchlorate should be further delayed. Therefore, EPA is 

developing a proposed rule for perchlorate. Once the perchlorate standard is promulgated, EPA is 

required to review and revise, as appropriate, its drinking water standards at least every six years. 

Any revision must at least maintain or improve public health protection. When there are sufficient 

scientific data to assess the cumulative risks of perchlorate and other contaminants, EPA will review 

this information to evaluate whether any revisions of NPDWRs are appropriate. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20960 

EPA Comment Code: 5220 

 

Comment: -Also the PBPK model used by EPA arrives at a HRL that closely matches the one 

obtained by using the total perchlorate equivalent level and applying an RSC =1. 

Because food exposure data and other relevant variables were recently available including for the 

most sensitive subpopulations, EPA chose to use a refined approach rather than EPAâ€TMs former 

"default" approach to estimate the RSC leading to the HRL. However it may be useful to compare 

this HRL and the HRL that would have been obtained by using the former "default" RSC approach 

particularly when adding additional considerations and evidence not taken into account neither by 

the former not by the latter approach. 

Response: See response to comment code 5220 for a description of the potential alternative HRLs 

and comment code 5210 for a discussion of the RSC. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20962 

EPA Comment Code: 5220 

 

Comment: 1. Determination of HRL applying an RSC or not 

1.1. Introduction 

(Note: from hereon we specify the NOEL, RfD and HRL as NOEL1,NOEL2 ,NOEL3 and 

NOEL4 ;RfD1,RfD2 ,RfD3 and RfD4 ;HRL1 , HRL2, HRL3 and HRL4 according to their 

subsequent specific meanings in this comment while with NOEL, RfD and HRL is meant their 

general meaning). 

EPA bases its HRL for DW (drinking water) on the NRC (National Research Council) RfD 

(Reference Dose, 0.7ug/kg-day) according to the following equation: 

HRL = [(RfD Ã— BW)/DWI] Ã— RSC with BW= Body weight = 70 kg and DWl = drinking 

water daily intake in litres. 

Response: No response necessary to this summary of EPA information. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20966 

EPA Comment Code: 5220 

 

Comment: 2. The very particular case of perchlorate 

Two particular considerations should be taken into account in determining a "state of the art" HRL 

for perchlorate besides the fact that the RSC should be equal to 1 and the fact that the full effective 

NOEL and RfD should be taken into account. 

A. The background is known for perchlorate 

To our knowledge this is the first time that background data are available that would allow to 

calculate an effective NO(A)EL for a contaminant for which a RSC is not needed to set a HRL. 

Using the data and regression curves presented in Blount et al., (2006,b) (2) the average urinary 

perchlorate level of 2.84 ug/l (with a 95% confidence interval of 2.54-3.18 ug/l) translates into an 

average exposure or total background( food +DW) of around 0.04 ug /kg-day (which is 17times 

lower than the 0.7 ug /kg-day RfD). 

The estimation of the effective Greer NOEL (NOEL3) is therefore still ? NOEL1 ? Âμg /kg-day. 

At first sight this is reassuring as it does not matter much if the background perchlorate would be 
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taken into account or not or whether the background food perchlorate level would have been 

subtracted already or not since NOEL3 is almost equal to NOEL1 meaning that also HRL3 would 

be almost identical to the HRL1 of 24.5 ppb. 

It also shows that perchlorate background levels (food +DW) in the U.S. population are very low to 

start with as they represent only around 0.5 %( = 0.04/7) of the effective perchlorate NOEL3 and 

apparent perchlorate NOEL1 and 5% of the RfD. 

Yet there is more to be considered. 

Response: See response to comment code 5210 for a discussion of the RSC and comment code 

5220 for a discussion of the potential alternative HRLs. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20969 

EPA Comment Code: 5220 

 

Comment: Yet, surprisingly, even though EPA refers to those goitrogens when discussing the 

Blount et al., (2006b) (2) biomonitoring study it does not take into account the available data that 

would allow it to significantly refine the RfD and the corresponding HRL. 

If EPA would have done so, EPA would have found that the background level of the other 

goitrogens are, as noted, much more important than the one of perchlorate itself and should 

therefore been taken into consideration a priory. As mentioned the total perchlorate equivalent RfD 

should have been 1.28 ug/kg-day and the old DWEL of 24.5 ppb should be replaced by one of 

around 45 ppb for [perchlorate +nitrate /240]. 

The current MCL for nitrate is 44 ppm (10 ppm as nitrate) which translates into a 183 ppb 

perchlorate equivalent (44,000/240). 

For Methemoglobinemia on which the nitrate MCL was based, a RSC of 1 and a UF of 1 was 

applied. A RSC of 1 was justified as explained above however an UF of 1 may, as suggested by CDC 

(9), or may not have been justified .However for nitrate to be as health protective for iodine uptake 

inhibition as the perchlorate RfD the same UF as perchlorate should have been applied when 

assuming that 44 ppm is a NOEL. On the contrary most probably 44 ppm is already above the 

NOEL (10). 

In that case the new nitrate MCL would have an equivalent of 18.3 ppb perchlorate. This would 

then leave a HRL of 45 -18.3 = 26.7 ppb for perchlorate alone which, by the way, is close to the 

current EPA DWEL of 24.5 ppb. 

Response: See response to comment ID 20958 under comment code 5220. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 
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EPA Comment ID: 20971 

EPA Comment Code: 5220 

 

Comment: 3. A few checks of the current EPA approach in setting a HRL 

As noted before, when, because of the trial set-up, the dose that allowed to determine a NOEL (or 

NOAEL) was not complementary to a background dietary level, the application of an RSC< 1 is 

necessary to come to a HRL for water only. 

In that case most of the time a default RSC is used because of lack of more precise data. This makes 

the RSC an imprecise tool .Therefore a data based estimate such as the FDA TDS model used by 

FDA would, while still a model, have been an improvement. 

However, as explained, trying to derive a HRL from the perchlorate RfD, applying an RSC<1 is not 

justified since the food contribution was already taken care of. 

Yet the data on the perchlorate background and the total equivalent perchlorate background can be 

used to check the RSC based on the FDA TDS model and to check the EPA HRL based on the 

PBPK model 

Response: See response to comment code 5210. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20973 

EPA Comment Code: 5220 

 

Comment: 3.2. HRL check 

For the most sensitive population, as designated by EPA, and assuming a same nitrate and 

thiocyanate background intake as the Greer cohort , the perchlorate food dose for the highest 10% 

of this population segment is 0.26 ug/kg-day(see EPA table 6). 

The (new) RfD that remains for DW would then be: 0.77-0.26 = 0.51 ug/kg-day which leads to a 

DW HRL of 17.8 ppb (0.51x70/2) which is close to the 15 ppb found by EPA for this sensitive 

group. 

(1) Greer, M.A., G. Goodman, R.C. Pleuss, and S.E. Greer. Health effect assessment for 

environmental perchlorate contamination: the dose response for inhibition of thyroidal radioiodide 

uptake in humans. Environ Health Perspect. 2002. Vol. 110. pp. 927-937 

(2) Blount, B.C., J.L. Pirkle, J.D. Osterloh, L. Valentin-Blasini, and K.L. Caldwell. Urinary 

perchlorate and thyroid hormone levels in adolescent and adult men and women living in the United 

States. Environmental Health Perspectives. 2006b. Vol. 114, No. 12. pp. 1865-1871. 

(3) EPA, Office of Water , Office of Science and Technology, Methodology for Deriving Ambient 

Water Quality Criteria for the Protection of Human Health (EPA-822-B-00-004), 2000. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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(4) Tonacchera M., Pinchera A., Dimida A., Ferrarini E., Agretti P., Vitti P., Santini F., Crump K., 

Gibbs J. Relative Potencies and additivity of perchlorate, thiocyanate, nitrate, and iodide on the 

inhibition of radioactive iodide uptake by the human sodium iodide symporter. Thyroid 14: 1012-

1019. 2004. 

De Groef B., Decallonne BR., Van der Geyten S., Darras VM., Bouillon R. Perchlorate versus other 

environmental sodium/iodide symporter inhibitors : potential thyroid-related health effects. 

European Journal of Endocrinology. 2006, 155: 17-25. 

(5) Cardoso A. P., Ernesto M., Nicala D., Mirione E., Chavane L., Nâ€TMzwalo H., Chikumba S., 

Cliff J., Mabota A. P. , Haque M. R., Bradbury J. H. Combination of cassava flour cyanide and 

urinary thiocyanate measurements of school children in Mozambique. International Journal of Food 

Sciences and Nutrition. May 2004. Volume 55, Number 3, 183-190 

(6)Smith R. G., Malcom R. M. Urinary sulphur and thiocyanate excretion in cyanide poisoning. 

American Society for Pharmacology and Experimental Therapeutics. Journal of Pharmacology And 

Experimental Therapeutics. 1930. Vol. 40, Issue 4, 457-471, 

http://jpet.aspetjournals.org/cgi/content/abstract/40/4/457 

(7) Florin T. H. J., Neale G., Cummings J. H. The effect of dietary nitrate on nitrate and nitrite 

excretion in man. MRC Dunn Clinical Nutrition Centre, 100 Tennis Court Road, Cambridge CB2 

IQL. Addenbrooke's Hospital, Hills Road, Cambridge CB2 2QQ. (Received 5 September 1989 - 

Accepted 11 May 1990. 

(8) Vermeer I. T. M., Pachen D. M. F. A., Dallinga J. W. , Kleinjans J. C. S, van Maanen J. M. S. 

Volatile N-Nitrosamine Formation after Intake of Nitrate at the ADI Level in Combination with an 

Amine-rich Diet. Department of Health Risk Analysis and Toxicology, Maastricht University, The 

Netherlands. Environmental Health Perspectives. August 1998. Volume 106, Number 8. 

(9) Manassaram D.M., Backer L. C., Moll D. M. A Review of Nitrates in Drinking Water: Maternal 

Exposure and Adverse Reproductive and Developmental Outcomes. Centers for Disease Control 

and Prevention, National Center for Environmental Helath, Health Sudies Branch, Atlanta, Georgia, 

USA. Environmental Health Perspectives. March 2006. Volume 114, number 3. 

(10) TAJTAKOVA M.; SEMANOVA Z., TOMKOVA Z., SZÃ–KEOVA E., MAJOROS J., 

RADIKOVA Z., SEBÃ–KOVA E., KLIMES I., LANGER P. Increased thyroid volume and 

frequency of thyroid disorders signs in schoolchildren from nitrate polluted area. Chemosphere, 

ISSN 0045-6535 CODEN CMSHAF. 2006, vol. 62, no4, pp. 559-564 [6 page(s) (article)] (18 ref.). 

RADIKOVA Z., TAJTAKOVA M., KOCAN A., TRNOVEC T., SEBÃ–KOVA E., KLIMES I., 

LANGER P. Possible Effects of Environmental Nitrates and Toxic Organochlorines on Human 

Thyroid in Highly Polluted Areas in Slovakia. Thyroid ISSN 1050-7256. 2008, vol. 18, no3, pp. 353-

362 [10 page(s) (article)]. 

Response: See response to comment ID 20958 under comment code 5220. 

Commenter Name: Jennifer Sass, PhD. 
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Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20985 

EPA Comment Code: 5220 

 

Comment: In simple terms, the HRL is the maximum contamination level of perchlorate that could 

be in drinking water, and still keep daily human consumption levels from exceeding the RfD of 0.7 

ug/kg/day. EPA reports that for pregnant women, exposure to perchlorate from food is 0.263 

ug/kg/day at the 90th percentile (based on data from a national food survey), representing nearly 

38% of the RfD, thus leaving an RSC (Relative Source Contribution) for water of 62% (FR at 

60276). This is equivalent to 0.437 ug/kg/day from water, assuming an average body weight of 70 

kg, and a daily water consumption of 2 L (90th percentile adult water consumption). That is, 0.437 

ug x 70 kg body wt. = 30.6 ug perchlorate in 2 L (the daily consumption amount). This is 15 ug/L, 

or 15 ppb, the HRL. 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 21007 

EPA Comment Code: 5220 

 

Comment: However, even if EPA proceeds with its determination not to regulate perchlorate and 

instead finalizes an HRL, that level must be adjusted to account for the actual data from the PBPK 

model showing that hundreds of thousands of infants would exceed the safe daily perchlorate intake 

levels at the proposed HRL. 

These comments are respectfully submitted for your consideration, 

Jennifer Sass, Ph.D. Mae Wu, JD 

COMMENTS SUPPORTED BY THE FOLLOWING: 

Center for Public Environmental Oversight a project of the Pacific Studies Center Lenny Siegel, 

Executive Director Mountain View, CA 

Citizens for Safe Water Around Badger Laura Olah, Executive Director Merrimac, WI 

Clean New York Bobbi Chase Wilding, Organizing Director Schenectady, NY 

Concerned Citizens of the Plainview-Old Bethpage Community Inc. Carol Meschkow, President 

Plainview, New York 

Environmental Health Fund Judith Robinson, Director of Programs Jamaica Plain, Boston 

Greenpeace Rick Hind Washington, DC 
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Institute for Agriculture and Trade Policy David Wallinga, MD Minneapolis, MN 

Natural Resources Council of Maine Matt Prindiville, Project Director Toxics and Sustainable 

Production Maine, USA 

Physicians for Social Responsibility Evan Krasner, MD, Executive Director SF Bay Area Chapter 

ScienceCorps Kathy Burns, Ph.D. Boston, MA 

Response: See response to comment code 5220. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21058 

EPA Comment Code: 5220 

 

Comment: The EPA has determined that setting a NPDWR will not present a meaningful 

opportunity for health risk reduction based on assessments done by multiple authoritative scientific 

bodies, numerous well conducted human and animal experiments using a range of doses of 

perchlorate, and the occurrence and concentration of perchlorate in drinking water systems in the 

U.S. One of the rationales for this decision was the calculation of the HRL which was based on the 

RfD. The RfD combined this previous knowledge to determine a dose which is well above the 

threshold in healthy adults that does not cause inhibition of iodide uptake and dividing that dose by 

10 to account for sensitive populations. 

Response: See response to comment ID 20279 under comment code 5220. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21078 

EPA Comment Code: 5220 

 

Comment: III. IODINE SUFFICIENCY IN THE UNITED STATES 

A significant degree of attention and concern related to perchlorate exposure has been focused upon 

the hypothetical iodine-deficient person. However, unless the doses of perchlorate are sufficient to 

significantly impair long term (not transient) iodide uptake, which would be considerably greater 

than 0.007 mg/kg-d (~240 ppb based on healthy adults; Greer et al. 2002), perchlorate exposure 

would not exacerbate iodine deficiency. As stated above, this dose was adjusted by an uncertainty 

("safety") factor of 10. Thus, the approach used by EPA in deriving their HRL based on the RfD of 

0.7 ug/kg-d, remains a conservative and health protective approach that accounts for substantial 

uncertainty. The NRC definitively states 

"...a dose that does not inhibit thyroid iodide uptake will not affect thyroid function, even in subjects 

with an abnormal thyroid gland or a very low iodide intake." 
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There is concern that there are low iodine levels in the U.S. population. The concern is that low 

iodine levels in a pregnant woman for prolonged periods of time can cause a change in thyroid 

hormones that may affect the neurodevelopment of the fetus. 

First and foremost, it is important to note that no study has demonstrated that exposure to 

environmentally-relevant levels of perchlorate causes or is associated with iodine deficiency. Taken 

at face value, Blount et al. (2006) show an association between thyroid disruptions and perchlorate; 

however, even if this association represented an actual biological effect at doses below the inhibition 

of iodine uptake, this hypothetical effect does not raise or lower the measured thyroid hormones 

outside of the normal ranges and do not show any adverse effect due to the exposure. An 

epidemiological study of chronically exposed populations in Chile, including children who were 

exposed throughout gestation via maternal exposure and in infancy through breastmilk and later 

dairy, show no adverse effects with exposure much higher than the RfD even with iodine intakes 

similar to that in the U.S. (Tellez et al., 2005). 

Second, the TDS and NHANES both show that population intake of iodide exceed the 

recommended adequate intake for iodine (Murray et al., 2008; Blount et al., 2006). Although there 

have been questions regarding iodine sufficiency in the U.S., Borak (2005) points out that there has 

not been consistency regarding the application of WHO definitions of iodine insufficiency and 

interpreting the great variability in daily iodine levels (Borak, 2005). For instance, for a population to 

be considered iodine deficient by the WHO definition, the median urinary iodine concentration 

must be below 100 ug/L and at least 20% of the population must be below 50 ug/L. Borak notes 

that much of the confusion in the interpretation of NHANES data comes from this seemingly high 

number of people that may be below 50 ug/L urinary iodine. He explains "...the reason for such 

seemingly inconsistent criteria is the need to anticipate potentially large variability when iodine levels 

are measured in spot urine samples" (Borak, 2005). 

Third, despite the presence of perchlorate in breast milk, studies have shown that this level of 

perchlorate does not cause adverse effects in children (Tellez et al., 2005; Amitai et al., 2007). 

Moreover, these studies have all shown doses of perchlorate that are below the NOEL from Greer 

et al. (2002), and are therefore insufficient to inhibit iodide uptake by the NIS. If a person, or a 

population, is iodine insufficient, reducing perchlorate, at environmental relevant concentrations, 

will not improve iodine insufficiency. Supplemental iodine will (e.g., iodized salt) reduce or negate 

iodine insufficiency. 

Fourth, the NRC perchlorate panel concluded that iodide deficiency if it even exists in the U.S., is 

mild and "...perchlorate exposure most likely would not exacerbate it" (NRC, 2005). Finally, the RfD 

is a conservative health protective value that is based on a NOEL with the addition of a safety factor 

to account for the most sensitive individuals. The HRL, which is even more conservative than the 

RfD, was calculated based on pregnant women and was verified using PBPK modeling to consider 

whether the HRL would be protective of other sensitive subpopulations, including infants, by 

factoring in body weight, water intake, and food intake. 

Response: The data underlying the definition of iodide uptake inhibition as a precursor effect and 

the relationship of iodide uptake inhibition to the continuum of adverse outcomes reflects an 

understanding of effects in adults; it may not reflect the relationship of the precursor event to 

adverse outcomes in neonates and infants, who may not have iodide stores sufficient to offset the 

effects of reduced iodide uptake. The less resilient neonatal and infant system makes the exposure 
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gap between a precursor event (iodide uptake inhibition due to perchlorate) and reduced T3/T4 

levels likely to be narrower than for adults, and in fact, the distinction between the two may be 

blurred for the very young (Greer et al., 2002; Savin et al., 2003; van den Hove et al., 1999). The 

NRC noted that, “[T]he minimal prolonged decrease in thyroid hormone production that would be 

associated with adverse health effects is not known; any decrease is potentially more likely to have 

adverse effects in sensitive populations (people with thyroid disorders, pregnant women, fetuses, 

and infants) but data are not available to determine the magnitude of the decrease needed to cause 

adverse effects in those populations.” 

With regards to conclusions of the NRC panel on the effects of perchlorate exposure EPA believes 

the NRC appropriately based the RfD on iodide uptake inhibition to the thyroid, for the reasons 

discussed in its report. 

See response to comment code 5220. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21098 

EPA Comment Code: 5220 

 

Comment: V. EPA's Methodology to Support the HRL Could be Explained More Completely 

In the preliminary determination, EPA puts forth a methodology to measure the contribution of 

food to total exposure by combining two nationally- representative data sets. The best available 

scientific understanding supports EPA's use of actual data as opposed to default parameters to 

derive the RSC. As EPA set out in its 2007 notice, EPA has multiple options to estimate the 

contribution of food to total exposure. At that time, the PSG presented analysis of the scientific 

merits of these options. The conclusions in those comments remain valid: no matter which 

scientifically-valid approach EPA takes, EPA can and should conclude that a national drinking water 

standard would not yield a meaningful reduction in human health risk. 

The approach outlined in the proposed determination and background document appears to have 

several limitations. These limitations may be omissions in the description and not in the 

methodology. While adequate to meet EPA's statutory obligation, we suggest that EPA's description 

could benefit from additional explanation. These suggestions are listed below. 

* Sample Description. Both UCMR and NHANES are nationally representative samples. The 

sample frame and the sample weights are published and have undergone peer review. EPA takes a 

subsample from these data sets and compares them for its analysis. EPA's analysis could benefit 

from a more complete description of the characteristics of these subsamples. Further description 

would assist the public especially since EPA is comparing absolute levels of perchlorate measured in 

drinking water and in total exposure. Many factors could influence absolute amounts of food and 

drinking water consumption in a person at a given time such as climate, weight, age, and income. It 

is unclear from the analysis how the sample populations in Bins I, II, and III compare on these 

characteristics. For example, if the Bin III (and more importantly, its subgroups) population has a 

larger Body Mass Index (BMI) than the average US population, the sample population may consume 

more food than average. In this scenario, Bin III's absolute amount of perchlorate may be larger 

than the typical person in the US. 
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* Sample Population Size. The importance of describing the sample in more detail is magnified by 

the small number of individuals in the sample results EPA uses. EPA uses the 90th percentile result 

from the 98 pregnant women in Bin III. EPA has not described the statistical relation of this sample 

to the US population. In addition, based on the shape of the distribution described in Blount (2006), 

the upper percentile results must be driven by relatively few observations. In other words, the 

analysis relies on the results from just a few women of unknown relationship to the whole US 

population or the subpopulation of pregnant women. 

Viewed in this way, EPA's analysis is a convenience, non-statistically representative sample that is 

comparable to other study populations in Greer et al. (2002), Pearce et al. (2007), Tellez et al. (2005), 

and Amati et al. (2007). These studies all show that for total doses in excess of the RfD, there are no 

measurable adverse health effects on the study populations, including sensitive populations. 

Therefore, while EPA constructs this study population to estimate an RSC, it primarily reinforces 

the PSG's position that no effects occur below the RfD even for sensitive subpopulations. Until 

EPA provides more description of its study population, its advantages over the other published, 

peerreviewed studies is unclear. 

* Temporal Comparison. In its background document, EPA describes how it linked the two study 

populations in the dimension of space - EPA assigned individuals to the bins based on whether a 

drinking water system in the county reported any single detection of perchlorate. EPA notes, but 

does not fully describe, how EPA handled temporal associations. The UCMR data was gathered 

from 2000 to 2005 according to EPA. The NHANES survey was conducted during 2001 and 2002. 

It is not clear whether EPA only used the UCMR counties that reported detections in 2001 and 2002 

or all years in the UCMR dataset. This consideration is important since many systems that detected 

perchlorate did not do so routinely. If EPA used the UCMR data from all years, EPA should 

describe how many individuals in the Bin III subgroups lived in counties with an actual detection 

during the 2001-2002 time period. 

Additionally, on the NHANES sample, it is unclear how EPA adjusted the food consumption data 

to reflect seasonality. People eat different foods at different times of the year. While NHANES 

adjusts for this fact in its study design, it is unclear how and if EPA did so in its subsample. For 

example, if 50 percent of the pregnant women in Bin III were surveyed by NHANES in the 

summer, the food consumption patterns (and the distribution of absolute levels of perchlorate) 

would be different than if only 25 percent were sampled during that time. 

* Concentrations below Detection Limits Assumed to be Zero. EPA notes that one limitation is that 

the analysis assumes that all detections below 4 ppb are assumed to zero. EPA states: 

It is uncertain how the 4 ug/l detection limit in the UCMR might affect the assignment of 

NHANES to Bin III. However, EPA believes that the classification is reasonable and that it is 

unlikely that any false negatives would significantly change the findings because there is a low 

frequency of occurrence above the method reporting limit (less than two percent of all samples had 

detects), it is reasonable to assume that there would be a corresponding low frequency of occurrence 

below it if at all. (EPA envisions a scenario with a high frequency of occurrence at very low 

concentrations unlikely). (pg 13) 

First, while the misclassification problem among bins is interesting, it is clear how the detection limit 

will bias the results within Bin III. Bin III is supposed to represent individuals that only receive 
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perchlorate through food. EPA uses the Bin III results to calculate the dose received from food. If 

some of this dose actually derives from drinking water, EPA is overestimating the dose from food, 

underestimating allowance available from drinking water, and underestimating the HRL. 

Consider this scenario. In the pregnant women subgroup of Bin III, the 98 pregnant women have an 

average estimated perchlorate intake of 0.123 ug/kg/day. In the analysis, EPA assumes the water 

contribution is zero. Suppose the true water concentration for the 98 women is 1/2 the detection 

limit (or 2 ug/l), a common EPA assumption in risk assessments and other 13 drinking water 

exposure scenarios. The women then receive a dose of 0.057 ug/kg/day from drinking water. This 

amount is 46 percent of their total dose. Their estimated food dose is correspondingly lower, the 

relative source contribution would be lower, and the HCL should be greater than 15 ppb. While the 

1/2 the detection limit is merely an assumption, it illustrates the main point - the censoring of the 

data due to the detection limit can have a large effect on the Bin III results. 

This effect will only be large if a significant proportion of the Bin III population has concentrations 

of perchlorate in drinking water below the levels of detection. EPA finds "high frequency of 

occurrence at very low concentrations unlikely." If "high" means 90 percent of the population, this 

scenario is unlikely. 

Table 2 in the proposed determination shows the estimated population served with at least one 

sample above the detection limit has an exponential shape to it (each time the concentration is cut in 

half, the estimated population exposed at that level doubles.) It is reasonable to assume that this 

relationship continues below the detection limit. By assuming all people in Bin III receive no 

perchlorate from drinking water, EPA overestimates the concentration from food and creates an 

overly conservative HRL. 

In summary, EPA's approach is scientifically appropriate in using actual observed data to estimate 

the RSC and the HCL. All approaches have limitations; however, any limitations in EPA's analysis 

have to be viewed in context of the extensive body of literature on perchlorate's mode of action and 

measured effects in humans. When EPA's analysis is viewed in the context of the NAS findings and 

other published studies, EPA's analysis is one more way to demonstrate that total exposure to 

perchlorate in the US is common and without adverse effect. EPA's analysis is more than adequate 

to demonstrate that perchlorate does not occur at a frequency and level of health concern to warrant 

an NPDWR. 

Response: See response to comment code 5220 for a discussion of the alternative Health Reference 

levels. Your observations regarding some limitations of the Huber et al. study are correct, and as you 

note changes in dietary habits or food sources over a year or the possibility of small water 

contribution to what is considered food-only source would change results in a minor way. Because 

NHANES collects samples at different times of the year the result we obtained will be applicable for 

the entire year, and small changes would not be significant from a health standpoint. The gap in the 

data of course is the lack of information on children less than 6 years old which has become a focus 

of concern. 

Commenter Name: Ellen Blaschinski, M.B.A., R.S. 

Commenter Organization: Regulatory Services Branch, Connecticut Department of Public Health 

EPA Document ID: EPA-HQ-OW-2008-0692-2091 

EPA Comment ID: 21115 
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EPA Comment Code: 5220 

 

Comment: However, in the October 10th Preliminary Regulatory Determination, EPA decided not 

to set a federal MCL for perchlorate. This was based upon the establishment of a drinking water 

Health Risk Limit (HRL) of 15 ug/L as the bright line for evaluating how many people would be 

exposed to concentrations of concern. The numerical target of 15 ug/L can be questioned on a 

number of fronts given that other recent derivations by states governments have yielded drinking 

water targets of 2 to 6 ug/L (New,Jersey, Massachusetts, California). The EPA assessment 

supporting the 15 ug/L HRL was reasonable in some regards (e.g., the mannner in which the 

relative source contribution was derived) but is not well justified when it comes to the level of 

exposure allowed for breast and bottle- fed infants. EPA's own assessment puts this early life 

exposure at 2 to 5 times greater than the Agency's RfD, with this justified by the use of an 

exploratory pharmacokinetic model which has no possibility of being validated for children. Given 

that this a key population to protect, it is essential that the HRL be set such that the RfD is not 

exceeded in this group. This is especially the case given that the health protectiveness of the RfD has 

been questioned by the CDC study, which shows quite clearly that effects on thyroid hormone 

status are possible at levels of perchloratc below the RfD in adult women (Blount et al. 2006). 

The establishment of a lower HRL, more in line with recent derivations within several states, would 

yield a considerably larger public health impact than what was put forth by EPA in its draft 

determination. Therefore, this needs to be carefully reassessed. Our recommendation for a 

reassessment is in line with EPA's own Science Advisory Board which called EPA's decision 

premature stating that; "Given perchlorate's wide occurrence and well-documented toxicity to 

humans, the Science Advisory Board strongly believes that there must be a compelling scientific 

basis to support a scientific determination not to regulate perchlorate as a national drinking water 

contaminant" (SAB letter, November 5, 2008). 

Response: See response to comment code 5220. 

Commenter Name: Mark S. Mayer 

Commenter Organization: South Dakota Department of Environment & Natural Resources 

(DENR) 

EPA Document ID: EPA-HQ-OW-2009-0297-0467 

EPA Comment ID: 28482 

EPA Comment Code: 5220 

 

Comment: - Comment on the Health Reference Level Issues - South Dakota DENR agrees the 

process presented appears to be reasonable. 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Richard Nieuwenhuis 

Commenter Organization: New Jersey Farm Bureau (NJFB) 

EPA Document ID: EPA-HQ-OW-2009-0297-0665 

EPA Comment ID: 28534 

EPA Comment Code: 5220 

 
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Comment: Moreover, the Environmental Protection Agency has not presented any sound scientific 

evidence that sufficiently explains why the previous health reference level (HRL) that supports a 

drinking water equivalent of 15 ug/L is inadequate. The 15 ug/L HRL was established from 

scientifically supported literature and based on the most sensitive sub-population, plus an added tenfold safety factor. 

We understand that the scientific evaluation of perchlorate has become complicated over the past 

few years but believe that there remains a significant need for more comprehensive scientific 

evaluation and debate. 

We appreciate your attention to our concerns. 

Sincerely, Richard Nieuwenhuis President 

Response: See response to comment ID 28799 under comment code 5220. 

Commenter Name: Anthony Russo 

Commenter Organization: Chemistry Council of New Jersey (CCNJ) 

EPA Document ID: EPA-HQ-OW-2009-0297-0673 

EPA Comment ID: 28688 

EPA Comment Code: 5220 

 

Comment: October 6, 2009 

Water Docket Environmental Protection Agency Mailcode 2822T 1200 Pennsylvania Avenue 

Washington, DC 20460 

RE: "Drinking Water: Perchlorate Supplemental Request for Comments" 74FR159:41883, August 

19, 2009 

Dear Sir/Madam: 

The Chemistry Council of New Jersey (CCNJ) represents the interests of over 100 manufacturers in 

the business of chemistry in the Garden State. Our mission is to advance members' interests, 

operational and environmental excellence, science education and community outreach. 

The CCNJ appreciates this opportunity to provide comments on the above referenced public notice 

regarding alternative approaches to the interpretation of scientific data relevant to a regulatory 

determination for perchlorate in drinking water. 

CCNJ has several concerns about this issue. We believe that good public policy must be developed 

and proposed using sound, proven scientific data and presented in a manner which the public can 

understand and make informed judgments to determine application and appropriate risk prevention 

practices. 

Repeated scientific investigation, including a landmark National Academy of Sciences (NAS) review, 

result in a clear and consistent conclusion: low levels of perchlorate are not dangerous to public 

health. We should not ignore this data. Without the presentation of supporting scientific literature 
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justifying alternative analysis, it becomes difficult for EPA to demonstrate why this alternative would 

support a science based regulatory determination under the Safe Drinking Water Act (SDWA). Not 

only has EPA not presented any justification for an analysis based on an alternative health reference 

level that uses water intake and body weight measurements at specific life stages, but EPA has also 

not presented any scientific evidence that indicates why the previous HRL that supports a drinking 

water equivalent of 15 ppb, based on the most sensitive subpopulation, with an added ten fold safety 

factor and derived from the scientifically supported literature is inadequate. 

Response: See response to comment ID 28799 under comment code 5220. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28799 

EPA Comment Code: 5220 

 

Comment: EPA tried to support its conclusions that a 15 ppb HRL is safe by avoiding reference to 

the RfD, and instead referring to the level of inhibition of radioactive iodide uptake (RAIU) on 

which the NRC report (NRC, 2005) based its recommended RfD.[FN32: 73 Fed. Reg. at 60277.] 

EPA cannot shift its evaluation of acceptable exposure estimates to a discrete biological endpoint 

that leads to exceedances of the RfD. 

Response: In the October 2008 preliminary regulatory determination, EPA had derived a single 

HRL of 15 μg/L based upon the RfD, an estimate of perchlorate exposure from food for pregnant 

women, and traditional adult body weight (70 kg) and drinking water consumption (2 L/day) values. 

This single HRL was derived to reflect exposure to a pregnant woman and her fetus, which the 

NRC identified as “the most sensitive population.” 

Since the NRC also identified infants and developing children as additional life stages, EPA derived 

potential alternative HRLs for 14 life stages (age groups) using the RfD and life stage-specific 

exposure information in the August 9, 2009, notice (74 FR 41883; USEPA 2009b). These levels 

range from 1 μg/L to 47 μg/L and are the concentrations of perchlorate in drinking water that may 

result in total perchlorate exposures (from food and water) greater than the RfD for individuals at 

each life stage. These HRLs are calculated based on individuals who consume an average amount of 

perchlorate from food (except for pregnant women where EPA used a 90th percentile dietary intake 

estimate), but who consume equal or more water on a per body weight basis than 90 percent of their 

cohorts. EPA has developed potential health reference levels (HRLs) for perchlorate for purposes of 

this regulatory determination. HRLs are not final determinations about the level of a contaminant in 

drinking water that is necessary to protect any particular population. Rather they are benchmarks 

against which EPA compares the concentration of a contaminant found in public water systems to 

determine if it is at levels of public health concern. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28802 

EPA Comment Code: 5220 

 

Comment: RESPONSE TO REQUEST FOR COMMENTS ON THE HRL 
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In simple terms, the HRL is the maximum tolerable amount of perchlorate that could be in drinking 

water, considering that perchlorate is also in food, and still keep daily consumption levels from 

exceeding the RfD. The 2008 proposed HRL of 15 ppb was calculated as follows: For all 

populations, including pregnant women, EPA determined that the RfD is 0.7 ug/kg/day. This value 

is posted on the IRIS database based on recommendations from a committee of the NRC. EPA 

reports that for pregnant women, exposure to perchlorate from food is 0.263 ug/kg/day at the 90th 

percentile (based on data from a national food survey), representing nearly 38% of the RfD, thus 

leaving an relative source contribution (RSC) for water of 62%.[FN43: 73 Fed. Reg. at 60276)] This 

is equivalent to 0.437 ug/kg/day from water, assuming an average body weight of 70 kg, and a daily 

water consumption of 2 L (90th percentile adult water consumption). That is, 0.437 ug x 70 kg body 

wt. = 30.6 ug perchlorate in 2 L (the daily consumption amount). This is 15 ug/L, or 15 ppb, the 

HRL proposed in the October 2008 FR notice. 

Response: No response necessary to this summary of EPA information. 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0527 

EPA Comment ID: 28916 

EPA Comment Code: 5220 

 

Comment: Based on the above comments, we urge USEPA to reconsider its proposed HRL of 15 

ug/L. 

Response: See response to comment ID 28799 under comment code 5220. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 29096 

EPA Comment Code: 5220 

 

Comment: Because the RfD was based exclusively on the dose-response calculations derived from 

the Greer et al study, then the HRL also relies on that data to derive a maximum allowable level of 

drinking water contamination. The derivation of a health-based standard for perchlorate should 

reflect the best available data, including published data collected and analyzed by the CDC and 

described by Blount (2006) and Blount (2007).[FN43: Blount BC, Valentin-Blasini L, Osterloh JD, 

Mauldin JP, Pirkle JL. Perchlorate exposure of the US Population, 2001-2002. J Expo Sci Environ 

Epidemiol. 2007 Jul;17(4):400-7. Epub 2006 Oct 18. Blount BC, Pirkle JL, Osterloh JD, ValentinBlasini L, Caldwell KL. Urinary perchlorate and thyroid hormone levels in adolescent and adult men 

and women living in the United States. Environ Health Perspect. 2006 Dec;114(12):1865-71.] As 

noted above, these data have the following advantages over the Greer et al data: 

1. Although the CDC data are from a cross-sectional analysis, because the survey includes a large 

number of individuals, the variability represents random error, not bias, and the data are likely to be 

representative of chronic perchlorate exposure; 
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2. The number of individuals included in the CDC study are sufficient for the specific analysis of a 

sensitive subpopulation defined as women with low iodine intake; 

3. A benchmark dose (BMD) analysis of perchlorate-related modulation of serum thyroid hormone 

concentrations is feasible; and 

4. Perchlorate exposures, as measured by urinary perchlorate concentration, corresponding to the 

benchmark dose low (BMDL) can be converted to an estimated dose in mg/kg-day, that can be used 

as the point of departure for the derivation of both the MCL and HRL. 

The mean for total serum T4 concentrations in women is 8.27 ug/dL and the 25th percentile of 

perchlorate exposure (equivalent to 1.6 ppb perchlorate in urine) is associated with a 10% drop in 

total serum T4 in women with low iodine intake.[FN44: Blount BC, Pirkle JL, Osterloh JD, 

Valentin-Blasini L, Caldwell KL. Urinary perchlorate and thyroid hormone levels in adolescent and 

adult men and women living in the United States. Environ Health Perspect. 2006 Dec;114(12):1865-

71.] 

Response: See response to comment ID 28863 under comment code 2110. 

 
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EPA Comment Code: 5225 Use of alternative HRLs specific to sensitive life 

stages, as described in Table 2 of the August 2009 FR notice. 

Individual Comments 

Commenter Name: W. Cucinotta 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0038 

EPA Comment ID: 28338 

EPA Comment Code: 5225 

 

Comment: Enclosed are my comments on your approaches for deriving HRLs on Perchlorates and 

other chemicals in our drinking water. 

4. 

a. No, I do not feel EPA appropriately took into account specific and appropriate exposure values 

for all potentially sensitive life stages, including infants, children and the fetuses of pregnant women. 

Any exposure to these type of chemicals should be eliminated and controlled to protect Americas' 

drinking waters. The 70 kg body weight and 2 liter per day consumption used for past regulatory 

determinations are grossly inappropriate levels to consider safe. 

b. I feel none of these these values are low enough to be appropriate levels to determine health 

concerns against which to compare the levels of perchlorates found in public water systems. I urge 

you to adopt the smallest exposer levels considered or preferably lower them to no (0) exposure at 

all. 

c. I feel the EPA did not use the best available and most appropriate data to estimate alternative 

HRLs in Table 2 because you cannot control how much water any one person consumes or the 

amount of perchlorate exposure from other sources. No, your drinking water ingestion rates in 

Table 2 do not take into account the life stages (birth to 6 months, and women ages 15-44) and does 

not provide an accurate representation of the exposure to the most vulnerable life stages because 

you cannot control how much water any one person consumes or the amount of perchlorate 

exposure from other sources.? 

Response: See response to comment code 5220 for a discussion of HRL derivation. Regarding 

health implications of exposures above the potential alternative HRLs, EPA notes that the data 

underlying the definition of iodide uptake inhibition as a precursor effect and the relationship of 

iodide uptake inhibition to the continuum of adverse outcomes reflects an understanding of effects 

in adults; it may not reflect the relationship of the precursor event to adverse outcomes in neonates 

and infants, who may not have iodide stores sufficient to offset the effects of reduced iodide uptake. 

The less resilient neonatal and infant system makes the exposure gap between a precursor event 

(iodide uptake inhibition due to perchlorate) and reduced T3/T4 levels likely to be narrower than 

for adults, and in fact, the distinction between the two may be blurred for the very young (Greer et 

al., 2002; Savin et al., 2003; van den Hove et al., 1999). The NRC noted that, “[T]he minimal 

prolonged decrease in thyroid hormone production that would be associated with adverse health 

effects is not known; any decrease is potentially more likely to have adverse effects in sensitive 

populations (people with thyroid disorders, pregnant women, fetuses, and infants) but data are not 
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available to determine the magnitude of the decrease needed to cause adverse effects in those 

populations.” 

Commenter Name: James D. Taft 

Commenter Organization: Association of State Drinking Water Administrators 

EPA Document ID: EPA-HQ-OW-2009-0297-0525 

EPA Comment ID: 28498 

EPA Comment Code: 5225 

 

Comment: Comments on the Health Reference Level (HRL) Issues - While we are generally 

comfortable with the development of the alternative HRLs in Table 2 (page 41888), the key question 

is: what HRL should be used as the basis of the regulatory determination? This is where we have 

some concern. Ideally, the regulation of a contaminant would be targeted at the most sensitive 

subpopulations, no matter how small the subpopulation. However, we must also be cognizant of 

resource limitations and practical constraints. It may not be feasible to protect very small 

subpopulations with a general regulation but rather, it may be more appropriate to use other risk 

reduction approaches to target small groups that may have special sensitivity. We cannot 

recommend a specific HRL without a full understanding of the implications on the burden for water 

systems and states, which these data do not provide. The HRL of 15 ug/l, derived using the 

traditional approach, is a good starting point and would cover a large percentage of the population. 

In addition, EPA should evaluate a range of HRLs between 15 and 4 ug/l in connection with more 

sensitive subpopulations. The Agency could then consider these values, in combination with 

occurrence data, in order to determine the populations that could be protected by regulation and 

whether regulation at these lower levels would present a "meaningful opportunity for health risk 

reduction", as required by the Safe Drinking Water Act. 

Response: See response to comment code 5220. 

Commenter Name: Shannon Cunniff 

Commenter Organization: Department of Defense (DOD) 

EPA Document ID: EPA-HQ-OW-2009-0297-0411 

EPA Comment ID: 28518 

EPA Comment Code: 5225 

 

Comment: Department of Defense Comments on the August 19, 2009 USEPA Federal Register 

Notice [EPA-HQ-OW-2009-0297; FRL-8943-9] Drinking Water: Perchlorate Supplemental Request 

for Comments Pages 41883-41893 

Comments submitted by: Chemical Material Risk Management Directorate Organization: 

Department of Defense Date Submitted: 18 September 2009 

*Comment categories: Science or methods (S); Editorial, grammar/spelling, clarifications needed 

(E); or Other (O). Also please indicate if Major (M), i.e. affects the outcome, conclusions or 

implementation of the assessment. 

Comment No. 1 

Section 
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Page & Paragraph Global 

Comment As noted in his 9 March 2009 memorandum on Scientific Integrity, President Obama 

recognizes that science and the scientific process must inform and guide Administration decisions 

on a wide range of issues, including improvement of public health, protection of the environment. 

The memo underscores the importance of scientific integrity by further noting that if the public is to 

trust the science and scientific process informing public policy decisions there should be 

transparency in the preparation, identification, and use of scientific and technological information in 

policymaking. In embracing the President's commitment to scientific integrity, Administrator 

Jackson notes in her 9 May 2009 memorandum to EPA employees that the Agency's regulatory 

decisions should include a full explanation of the science issues addressed by the Agency, the data 

relevant to those issues, and the interpretations and judgments underlying the Agency's scientific 

findings and conclusions. 

Suggested Action, Revision and References (if necessary) To ensure consistency with Administration 

and Agency commitments to scientific integrity, the following issues need to be considered in a 

transparent and scientifically defensible manner prior to the determination of any Health Reference 

Level (HRL), because they can impact the conclusions drawn by the EPA in the potential for health 

risk reduction for perchlorate in drinking water. While these issues do not address all requests for 

comments on alternative approaches, they focus on issues that will have the most significant impact 

on the determination and acceptance of an alternative HRL. The main issues associated with the 

alternative approaches presented by EPA (2009) include the following: 1. The lack of transparency 

and assurance of quality in the determination of alternative HRLs. 2. Inadequate characterization of 

exposure to sensitive subgroups, specifically infants and the fetuses of pregnant women. 3. A lack of 

justification for elimination of the PBPK models from consideration in the determination of an 

HRL. 4. Recommended applications for the PBPK models in the development of an HRL. 

Category* S, M 

Response: EPA believes that it has been consistent with Administration and Agency commitments 

to scientific integrity. The August 2009 notice clearly discusses the basis for alternative health 

reference approaches and that EPA was re-evaluating how best to incorporate PBPK modeling 

analysis into its evaluation of perchlorate, if at all. 

Commenter Name: Shannon Cunniff 

Commenter Organization: Department of Defense (DOD) 

EPA Document ID: EPA-HQ-OW-2009-0297-0411 

EPA Comment ID: 28519 

EPA Comment Code: 5225 

 

Comment: Comment No. 2 

Section 

Page & Paragraph Global 
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Comment The current documentation of the suggested alternative HRLs based on body weight and 

water consumption of other life stages is inadequate. The development of this alternative approach 

relies heavily on the FDA total dietary survey (Murray et al. 2008) and the first Unregulated 

Contaminant Monitoring Regulation (UCMR 1). While these studies are well conducted and provide 

a significant resource for information, the documentation provided is not sufficient to demonstrate 

their application, nor to insure their reproducibility by other parties. 

Suggested Action, Revision and References (if necessary) To insure clarity it is recommended that 

sufficient documentation be provided. Under the Data Quality Act (Section 515 of the Treasury and 

General Government Appropriations Act of 2001 (PL 106-544, H.R. 5658), Federal agencies are 

charged with ensuring the quality, integrity, and objectivity of information provided. See also 

comment #s 11 and 14. 

Category* E, M 

Response: EPA disagrees that the documentation of the suggested alternative HRLs is inadequate. 

In the October 2008 and August 2009 notices, EPA presents in detail the Unregulated Contaminant 

Monitoring Rule data as well as the Food and Drug Administration’s Total Diet Study in 73 FR 

60269–72. EPA has described how those studies have been used in deriving health references. EPA 

believes these are the best available peer reviewed data and that they have been applied in a 

reproducible manner. 

Commenter Name: Shannon Cunniff 

Commenter Organization: Department of Defense (DOD) 

EPA Document ID: EPA-HQ-OW-2009-0297-0411 

EPA Comment ID: 28520 

EPA Comment Code: 5225 

 

Comment: Comment No. 3 

Section 

Page & Paragraph Global 

Comment By removing the PBPK models from consideration, the agency has effectively removed 

consideration of the age-dependent variations in biology, and is apparently assuming that all 

differences may be accounted for by addressing the differences in exposure. There are many agedependent differences, including exposure, clearance, protein binding, and NIS capacity, as well as 

extrathyroidal sites of iodide inhibition (placenta, milk) that influence perchlorate toxicology. The 

models were developed using specific data to quantify these differences, and while uncertainty may 

exist in specific parameter values, it is certainly better to estimate parameter values from data rather 

than ignoring their existence. Factors such as clearance, maternal-fetal transfer, and extrathyroidal 

inhibition cannot be addressed in a standard analysis based on adjusting Points of Departure (PoDs) 

by exposure differences. Indeed, in the current proposal, the uncertainty associated with these 

parameters is added to other uncharacterized uncertainty, which does not improve estimates of risk. 
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The alternative HRL approach represents, in fact, a decision to become less informed about the 

processes governing potential increased risk to the sensitive populations, giving the impression that 

it is better to ignore the uncertainty related to real biology than to attempt to account for it. 

Suggested Action, Revision and References (if necessary) Instead of using the 90th percentile for 

exposure and an RSC, a more mathematical approach should be used to assess uncertainty in model 

predictions (i.e., Monte Carlo). This would help define expected ranges of inhibition after taking into 

account both variability in exposure and intraspecies variability in biological parameters. Not only 

would this be a more quantitative way of accounting for uncertainty in exposure, but it would also 

address commenter's concerns about the model parameter uncertainty and transparency. 

Category* S. M 

Response: EPA disagrees that by not using the PBPK model the Agency is deciding to become less 

informed. See response to comment ID 20432 under comment code 5220 for a discussion of EPAs 

decision not to utilize the PBPK model. 

Commenter Name: Shannon Cunniff 

Commenter Organization: Department of Defense (DOD) 

EPA Document ID: EPA-HQ-OW-2009-0297-0411 

EPA Comment ID: 28523 

EPA Comment Code: 5225 

 

Comment: Comment No. 11 

Section III. B. 3. Alternative Approaches for Calculating HRLs 

Page & Paragraph Page 41888 Column 1 Para 1 

Comment Example of comment # 2: The document relies on information to characterize ingestion 

to early life stages, which represent a sensitive subgroup, based on sample sizes that do not meet 

minimum data requirements. While EPA (2009) states that these are the best available data, there is 

no indication that a comprehensive literature search was conducted to determine if additional data 

could be used to supplement or validate the data provided. 

Suggested Action, Revision and References (if necessary) It is recommended that a comprehensive 

literature search be performed and documented. 

Category* E 

 Comment No. 12 

Section III. B. 3. Alternative Approaches for Calculating HRLs 

Page & Paragraph pg 41888 Column 1-3 

Comment Based on the EPA's analysis of percent radioactive iodide uptake (RAIU) inhibition 

estimated with the PBPK model (Table 8, EPA 2008), the NRC (2005) identified the 7-day old 
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breast-fed infant and the fetus of the pregnant woman at 40 weeks as the most sensitive subgroups. 

Yet, in their attempt to develop alternative HRLs based upon body weight and water consumption, 

which appears to be the only alternative presented, EPA (2009) has not adequately characterized 

exposure to perchlorate by these subgroups. The Relative Source Contribution for perchlorate from 

food for the birth to 12 month life stages (Table 2, EPA 2009) is based on information provided in 

the FDA Total Dietary Survey (Murray et al. 2008). The EPA (2009) states that because no 

information was available from the TDS for the life stages from birth to 6 months of age, estimates 

for the nearest age range (6-12 months) was used. The intake from food provided by Murray et al. 

(2008) largely results from the determination of perchlorate in baby food and commercial formula 

ingested by children aged 6-11 months. From birth to six months, however, baby food would not be 

a significant portion of the diet. If intake is assumed to be mainly from commercial formula, the 

RSC may be similar, but this is a major uncertainty. Furthermore, intake from breast milk is not 

addressed at all using the HRL approach. It is not reasonable to assume the same dietary ingestion in 

the newborn ingesting breast milk alone, and the child that is eating solid food. It is, in fact, 

impossible to define perchlorate exposure in the breast-fed infant or the fetus, using this revised 

approach for defining an HRL. 

Suggested Action, Revision and References (if necessary) It is recommended that the alternative 

HRLs not be used to estimate risk for this sensitive subgroup. 

Environmental Protection Agency (EPA). 2008. Drinking Water: Preliminary Regulatory 

Determination on Perchlorate. Federal Register 73(198):60262-60282. 

National Research Council (NRC). 2005. Health Implications of Perchlorate Ingestion. National 

Academies Press, Board on Environmental Studies and Toxicology. January, 2005. 

Category* S. M 

Response: Regarding the recommendation to conduct and document a comprehensive literature 

search on information to characterize ingestion to early life stages, EPA believes that it did just that 

in developing EPA’s “Child-Specific Exposure Factors Handbook.” The information in the 

Handbook represents the best available peer reviewed data on drinking water ingestion rates for 

various life stages. 

Regarding the recommendation that alternative HRLs not be used to estimate risks for sensitive 

groups, EPA strongly disagrees. The NRC (2005) identified fetuses of iodide deficient pregnant 

women are the most sensitive life stage and also identified infants and developing children as 

sensitive life stages. . EPA estimates that at least 5.1 to 16.6 million people are served by PWSs, for 

which we have data, that have perchlorate contamination. 

EPA has determined that a NPDWR for perchlorate may reduce perchlorate exposures for these 

infants, children, and pregnant women to levels below the RfD, and therefore believes that this 

perchlorate exposure reduction presents a meaningful opportunity for the reduction of health risks 

for persons served by PWSs. 

EPA has made this determination based on a consideration of the best available peer reviewed 

science and data collected in accordance with accepted methods related to perchlorate occurrence in 
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drinking water, the presence of perchlorate in foods, and the health effects of exposure to 

perchlorate. 

National Research Council (NRC). 2005. Health Implications of Perchlorate Ingestion. National 

Academies Press, Board on Environmental Studies and Toxicology, January, 2005, Washington, 

D.C. 276pp. 

Commenter Name: Shannon Cunniff 

Commenter Organization: Department of Defense (DOD) 

EPA Document ID: EPA-HQ-OW-2009-0297-0411 

EPA Comment ID: 28524 

EPA Comment Code: 5225 

 

Comment: Comment No. 13 

Section III. B. 3. Alternative Approaches for Calculating HRLs 

Page & Paragraph Page 41888 Column 1-3 

Comment The major problem with the current approach is the lack of characterization of exposure 

by those sensitive subgroups identified by NRC (2005): the 7-day old breast fed infant and the fetus 

of the pregnant woman at 40 weeks of gestation. The available dietary surveys and drinking water 

ingestion rates are incapable of providing a means to determine potential intake for these sensitive 

subgroups. 

Suggested Action, Revision and References (if necessary) Incorporation of a PBPK model at this 

step would provide a reasonable method for estimating maternal transfer of perchlorate. One of the 

major strengths of the PBPK models is that they provide a platform for estimating fetal and infant 

dose using biological data on transfer rates and pharmacokinetic data in both the animal and human. 

These models have been tested against human iodide data, and when available, perchlorate data. It is 

true that the data sets available for validation were extremely limited. However, even limited data are 

better than the complete lack of data available to support the new approach. Derivation of an HRL 

for the breast fed infant and fetus needs to consider such complex biological processes as placental 

transfer, active uptake in the mammary gland, and extrathyroidal inhibition. In 2008, the PBPK 

models were used to address these issues. The current approach does not utilize the PBPK models, 

and in the process does not consider what is known about the important biological determinants of 

perchlorate transfer to the fetus and infant, the identified sensitive subgroups. 

Category* S. M 

Response: See response to comment ID 20432 under comment code 5220. 

Commenter Name: Shannon Cunniff 

Commenter Organization: Department of Defense (DOD) 

EPA Document ID: EPA-HQ-OW-2009-0297-0411 

EPA Comment ID: 28526 

EPA Comment Code: 5225 

 

Comment: Comment No. 15 
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Section IV. Consideration of Studies Published Since EPA Adopted the NAS RfD for Perchlorate 

Page & Paragraph Pages 41889 41891 

Comment EPA requests comment on whether EPA used the best available and most appropriate 

data to estimate alternative HRLs in Table 2. 

The HRL it is too simplistic and does not take into account the full range of scientific knowledge 

regarding coexposure to chemicals known to also bind to the NIS receptor. For example, it does not 

allow taking into account other relevant issues concerning thiocyanate and nitrate co-exposures. It 

also does not consider factors such as potential differences in the perchlorate "half-life" compared 

to thiocyanate and nitrate, and comparison of thyroid hormone effects. 

Suggested Action, Revision and References (if necessary) Evaluate the above referenced (see 

Comment #10) human sensitive subpopulation data using direct measurement of biological fluids to 

derive the HRL for perchlorate considering the cumulative risk of other goitrogens (thyocianate and 

nitrate from dietary sources). These data should be considered for use in and/or validation of the 

EPA models. 

Since not just perchlorate but also thiocyanate and nitrate are present in commonly ingested foods, 

as well as mother's and bovine milk, they all impact iodide uptake inhibition, and thus should be 

evaluated 

Category* S 

Response: While EPA acknowledges that nitrate and thiocyanate have the same mode of action as 

perchlorate, and that the effects of combined exposure to perchlorate, nitrate, and thiocyanate are 

additive, EPA does not believe there are sufficient scientific data currently available to assess and 

characterize the combined risk of these contaminants. EPA has committed to a drinking water 

strategy that outlines four principles to expand public health protection for drinking water (USEPA, 

2010b). One of these principles is to address contaminants as groups. However, EPA does not 

believe that regulatory action to address perchlorate should be further delayed. Therefore, EPA 

intends to develop a proposed rule for perchlorate. At such time as a NPDWR is promulgated, EPA 

is required to review and revise, as appropriate, its drinking water standards at least every six years. 

Any revision must at least maintain or improve public health protection. When there are sufficient 

scientific data to assess the cumulative risks of perchlorate and other contaminants, EPA will review 

this information to evaluate whether any revisions of NPDWRs are appropriate. 

Commenter Name: Kathy Dolan 

Commenter Organization: Food and Water Watch (FWW) 

EPA Document ID: EPA-HQ-OW-2009-0297-0526 

EPA Comment ID: 28610 

EPA Comment Code: 5225 

 

Comment: As suggested by previous commenter's, I believe that the Agency's proposed HRL, of 15 

micrograms/Liter, is too high. The alternative HRLs presented in Table 2 of your request for 
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comment notice, dated August 5, 2009, do not use the most appropriate data. The data in Table 2 

uses mean ingestion rates from the CSFII. The CSFII is already several years out of date. 

Response: See response to comment code 5220. Regarding use of CSFII data, EPA believes that it 

is the best peer reviewed science that is available on the consumption of drinking water. 

Commenter Name: Apparent Mass Mailing #11 - Food and Water Watch 

EPA Document ID: EPA-HQ-OW-2009-0297-0526 

EPA Comment ID: 28616 

EPA Comment Code: 5225 

 

Comment: As suggested by previous commenter's, I believe that the Agency's proposed HRL, of 15 

micrograms/Liter, is too high. The alternative HRLs presented in Table 2 of your request for 

comment notice, dated August 5, 2009, do not use the most appropriate data. The data in Table 2 

uses mean ingestion rates from the CSFII. The CSFII is already several years out of date. 

Response: Regarding the Agency's proposed HRL of 15 ug/L being too high, see response to 

comment code 5220. Regarding use of CSFII data, EPA believes that it is the best peer reviewed 

science that is available. 

Commenter Name: Sonia Salas 

Commenter Organization: Western Growers Association on behalf of several California 

agriculture groups 

EPA Document ID: EPA-HQ-OW-2009-0297-0652 

EPA Comment ID: 28676 

EPA Comment Code: 5225 

 

Comment: The California agriculture groups submitting this letter appreciate the opportunity to 

comment on USEPA's August 19, 2009, Federal Register notice seeking comment on "additional 

approaches available for analyzing data related to EPA's perchlorate regulatory determination. The 

attached letter contains specific comments and information. Thank you for your consideration. 

October 8, 2009 

Mr. Eric Burneson Office of Ground Water and Drinking Water Standards and Risk Management 

Division Environmental Protection Agency 1200 Pennsylvania Avenue, NW Washington, DC 

20460 

Subject: California Agriculture Industry Comments on Docket Identification (ID) EPA-HQ-OW2008-0692-Perchlorate Supplemental Request for Comments 

Dear Mr. Burneson: 

The undersigned California agriculture groups appreciate the opportunity to comment on USEPA's 

August 19, 2009, Federal Register notice seeking comment on "additional approaches available for 

analyzing data related to EPA's perchlorate regulatory determination." Since a national primary 

drinking water standard for perchlorate would directly impact public perception of the safety of 

agricultural commodities known to contain trace amounts of perchlorate, it is critical that EPA 
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establish the appropriate science-based methodology before proceeding with a final regulatory 

determination. 

The California agriculture industry is a $37 billion industry that produces more than 350 different 

crop and livestock commodities and generates an estimated $100 billion in related economic activity. 

California agriculture accounts for approximately 7.5% of all employment and supports more than a 

million on-farm jobs. California agriculture is also the leading global exporter of agricultural 

commodities, sending almost 20% of our agricultural production to foreign markets. 

EPA's Proposed Alternative Health Reference Levels are Not Scientifically Justified and will 

Undermine Public Confidence in the Safety of Agricultural Commodities. 

EPA's August 19, 2009, Federal Register notice states that the "additional alternatives under 

consideration could result in health reference levels which are much lower than the level identified in 

the October 2008 notice." This statement causes great concern for the California agriculture industry 

because it implies that exposure to trace amounts of perchlorate may be harmful to human health, 

when in fact, the rich body of scientific literature on perchlorate does not support this conclusion. It 

is well established that many agricultural commodities contain trace amounts of perchlorate, but 

these levels are widely recognized as being orders of magnitude below any level that may pose a risk 

of adverse human health effects. EPA's promotion of the alternative health reference level concept 

will needlessly rekindle public concern about the safety of agricultural commodities and will drive 

some consumers away from these products to avoid perchlorate exposure. The negative impacts on 

public health associated with such a shift in dietary habits will vastly outweigh the risk of harm 

associated with exposure to trace amounts of perchlorate. 

Response: We appreciate your concern that food not be negatively impacted by evaluations of 

perchlorate in drinking water. The drinking water regulatory determinations health reference levels 

(HRLs) are calculated for public tap water and consider how much of the RfD is already taken by 

food exposure using a relative source contribution (see response to comment code 5220). Drinking 

water with perchlorate at levels less than the HRL may prevent the water-plus-food components of 

exposure from exceeding the RfD. 

Commenter Name: Anthony Russo 

Commenter Organization: Chemistry Council of New Jersey (CCNJ) 

EPA Document ID: EPA-HQ-OW-2009-0297-0673 

EPA Comment ID: 28690 

EPA Comment Code: 5225 

 

Comment: The Agency has sufficient data to show that perchlorate will not have an adverse effect 

on the health of persons at the levels expected in public drinking water systems, having based its 

RfD on a no observed effect level (NOEL) of a precursor to an adverse effect. Based on the 

available data, neither the first nor the second criteria of the SDWA are met. 

EPA along with other experts including the NRC committee, ATSDR and OEHHA have all 

identified the most sensitive life stage as the fetuses of hypothyroid or iodine deficient pregnant 

women. The NRC committee determined that all sensitive subpopulations, including infants, would 

be protected by the drinking water equivalent of EPA's reference dose, 15 parts per billion (ppb). By 

proposing to base its calculation of alternative health reference levels (HRL) on specific life stages as 
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opposed to the calculation based on the most sensitive sub- population (fetus), EPA would establish 

a scientifically unsupportable precedent that could then be applied to every other water contaminant 

for which and MCL has been established. EPA's calculation of alternative health reference levels 

(HRL) is not the best available science and thus runs contrary to EPA's duty under the Safe Water 

Drinking Act. 

Response: See response to comment ID 28338 under comment code 5225. 

Commenter Name: Kay Brothers 

Commenter Organization: Southern Nevada Water Authority 

EPA Document ID: EPA-HQ-OW-2009-0297-0667 

EPA Comment ID: 28697 

EPA Comment Code: 5225 

 

Comment: Alternative Health Reference Levels (HRLs) Based Upon Body Weight and Water 

Consumption of Other Life Stages 

Studies have clearly proven that perchlorate is a naturally occurring chemical which is absolutely 

ubiquitous in the environment (Sanchez, Krieger et al. 2005; Snyder, Vanderford et al. 2005; 

Valentin-Blasini, Mauldin et al. 2005; Baier- Anderson, Blount et al. 2006; Blount, Pirkle et al. 2006; 

Blount, Valentin- Blasini et al. 2006; Snyder, Pleus et al. 2006; Dyke, Ito et al. 2007). The evidence of 

perchlorate's ubiquity is indisputable based on the recent NHANES and FDA Diet Study, which 

clearly demonstrated that perchlorate is present in the human diet; thus, increasing the challenge of 

demonstrating "a meaningful opportunity for health risk reduction for persons served by public 

water systems" through federal regulation of perchlorate in drinking water. Moreover, a recent study 

led by the Authority (Snyder, Stanford et al. 2009) has demonstrated that the use of hypochlorite for 

the disinfection of water may contribute perchlorate at levels within the range of HRLs shown in the 

FR. Therefore, we urge the EPA to consider the consequences of suggesting HRLs that do not 

consider epidemiological data that include in utero perchlorate exposure. 

Response: EPA has carefully considered epidemiological data for perchlorate and determined that 

perchlorate meets SDWA’s criteria for regulating a contaminant. 

EPA agrees that perchlorate is naturally occurring. A 2006 study by a Texas Tech researcher 

(Dasgupta et al., 2006) identifies three principal sources of the perchlorate in the environment: its 

use as an oxidizer (rocket propellants, fireworks, flares and explosives), its presence in Chilean 

nitrate fertilizer, and formation via atmospheric processes. 

Perchlorate is soluble and is taken up by plants along with water and nutrients. Its presence in food 

specifically is related to: (1) past propellant leakage into irrigation source water (e.g., Colorado River) 

which is applied to fields of crops that are distributed nationally; (2) smaller application of Chilean 

fertilizer to certain crops, i.e., principally in organic farming; and finally (3) rainfall and localized 

irrigation with ground water containing natural perchlorates. 

Regarding the comment that the use of hypochlorite for the disinfection of water may contribute 

perchlorate at levels within the range of HRLs shown in the FR, EPA agrees that perchlorate has 

been found as an impurity in sodium hypochlorite which is commonly used by public water systems 

as a disinfectant to inactivate pathogenic micro-organisms. Reported concentrations of perchlorate 
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introduced as a result of disinfection using sodium hypochlorite range from 1 ppb to 8 ppb (Greiner 

et al., 2008). 

The extent to which perchlorate could be introduced into water from sodium hypochlorite depends 

on the operational practices of water utilities. In particular, the longer sodium hypochlorite is stored, 

the greater the concentration of perchlorate. These risk/risk tradeoffs can be addressed by 

implementing best management practices including storage in the dark at cool temperatures and use 

within 45 days of its manufacturing date. Perchlorate contamination resulting from sodium 

hypochlorite usage is more likely to occur in small drinking water systems than large. 

Commenter Name: Kate Sande 

Commenter Organization: Minnesota Department of Health, Health Risk Assessment Section 

EPA Document ID: EPA-HQ-OW-2009-0297-0663 

EPA Comment ID: 28701 

EPA Comment Code: 5225 

 

Comment: The Health Risk Assessment Unit with the Minnesota Department of Health 

appreciates the opportunity to submit comments in regards to EPA's Drinking Water: Perchlorate 

Supplemental Request for Comments (Docket ID No: EPA-HQ- OW-2009-0297). Please see our 

detailed comments found in the attached document. 

October 8, 2009 

Response to U.S. EPA, Drinking Water: Perchlorate Supplemental Request for Comments Docket 

ID No: EPA-HQ-OW-2009-0297 

The approach taken by the Minnesota Department of Health (MDH) to develop health-protective 

guidelines for groundwater is consistent with alternative approaches considered by the U.S. EPA in 

the development of a drinking water guideline for perchlorate. The approach used by MDH to 

develop health risk limits (HRLs) for drinking water are much more aligned with the process 

outlined by the EPA in the August 19, 2009 Federal Register announcement than the process 

described in the December 2008 Perchlorate Interim Drinking Water Health Advisory report. 

MDH supports EPA's August 2009 re-evaluation of the process used to develop drinking water 

guidelines for perchlorate. The previous approach used by the EPA in Interim Health Advisory 

Report was inconsistent with EPA risk assessment guidance. The use of the PBPK model appeared 

to be used to justify perchlorate exposure in infants and young children at levels above the RfD, an 

approach we would not endorse as health protective. Additionally, MDH was concerned by the lack 

of consideration of life stage sensitivities in the interim report, especially the absence of appropriate 

intake rates that were protective of sensitive subpopulations. 

Response: See response to comment code 5220 for a discussion of the HRLs. See response to 

comment ID 20432 under comment code 5220 for a discussion of the PBPK model. 

Commenter Name: Kate Sande 

Commenter Organization: Minnesota Department of Health, Health Risk Assessment Section 

EPA Document ID: EPA-HQ-OW-2009-0297-0663 

EPA Comment ID: 28702 
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EPA Comment Code: 5225 

 

Comment: Our comments include a discussion about how MDH accounts for life-stages 

sensitivities when developing HRLs and how our approach compares with the alternative 

approaches EPA is considering for developing a perchlorate drinking water guideline. We have also 

included an example of how MDH would calculate a HRL for perchlorate using EPA's RfD of 

0.0007 mg/kg-day and comments comparing the MDH drinking water guidelines and the alternative 

HRLs that EPA is considering (listed in Table 2, section III.B-3 of the Federal Register 

announcement). 

Note: If this were a chemical review conducted by MDH, we would independently review the 

toxicological literature to derive our own RfD, which may not result in the same RfD adopted by 

EPA for perchlorate. 

Section III, B-4.a - Request for comments about appropriate exposure values that consider sensitive 

life stages 

Intake Rates MDH strongly supports EPA's reconsideration to use life-stage specific, high end (95th 

percentile) drinking water intake rates in the development of alternative HRLs. This is consistent 

with the approach used by MDH and EPA's recommendation to evaluate exposures that are shorter 

than chronic durations to account for higher intake rates than can occur during shorter periods 

(EPA, 2002). Additionally, MDH agrees with EPA's approach to use appropriate and relevant body 

weights for sensitive individuals when calculating intake rates. 

To account for lower body weights and higher water intake rates by infants and young children 

during acute and short-term exposure durations, MDH uses an intake rate of 0.289 L/kg-day, based 

on the 95th percentile intake for an infant up to 3-months (EPA 2004 & EPA 2008a). The 

subchronic intake rate we use is 0.077 L/kg-day based on the time-weighted average of the 95th 

percentile intake from birth up to 8 years of age. The chronic intake rate used by MDH is 0.043 

L/kg-day and is based on the time-weighted-average of the 95th percentile intake over 

approximately 70 years. 

Response: See response to comment code 5220. 

Commenter Name: Kate Sande 

Commenter Organization: Minnesota Department of Health, Health Risk Assessment Section 

EPA Document ID: EPA-HQ-OW-2009-0297-0663 

EPA Comment ID: 28704 

EPA Comment Code: 5225 

 

Comment: Section III, B-4.b - Request for comments on the alternative HRLs in Table 2 and 

which would be an appropriate guideline 

The formula used by MDH to calculate a non-cancer health protective drinking water guideline is: 

Non-cancer Guidelineduration = (RfDduration x RSC x 1000) / Intake Rateduration 
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In the table below (Table 1) you will find the range of perchlorate concentrations in drinking water 

that MDH would derive based on our standard intake rates and relative source contributions 

described above for multiple exposure durations (acute, short-term, subchronic, and chronic). The 

drinking water concentrations derived below are for comparison purposes only and do no reflect 

current MDH guidance. 

Table 1. MDH drinking water guidelines compared to EPA HRLs for perchlorate. [see PDF docket 

ID EPA-HQ-OW-2009-0297-0663] 

*We adjusted the life stages used by MDH to conform to EPA's life stages listed in Table 2, section 

III.B-3 of the Federal Register announcement, however normally, MDH categorizes health 

guidelines by exposure durations as outlined in EPA's Reference Dose Process guidance (EPA, 

2002). 

**MDH does not calculate guidlines for each life stage listed in Table 2, section III.B-3 so we only 

included EPA HRLs that correspond to the life stages we consider at MDH. The EPA HRLs that 

were most appropriate for comparison were the ones calculated using the 95th percentile intake 

rates. 

*** We felt a chronic MDH guideline provided the most appropriate comparison to EPA's HRL for 

pregnant women. The EPA HRL is higher than the MDH guideline because MDH used our default 

RSC of 0.2 and EPA used an RSC of 0.62. 

Using the MDH HRL approach to calculate theoretical perchlorate drinking water guidelines 

resulted in a range of perchlorate concentrations of 1-3 ug/L which account for all life stages and 

sensitive subpopulations. Based on these concentrations, it is likely we would select 1 ug/L as the 

guideline to ensure the most sensitive individuals are protected. The EPA HRL of 2 ug/L for infants 

less than 3-months old is much more comparable to the MDH guideline than the interim HRL of 15 

ug/L. 

Section III, B-4.d Request for comments on the merits of the approach to derive HRLs for sensitive 

life stages based on the RfD combined the life stage specific exposure data 

MDH agrees with the approach of developing HRLs based on the RfD combined with life stage 

specific exposure data. When developing an HRL, MDH conducts an independent review of the 

toxicological literature to develop an RfD and calculates a drinking water guideline using intake rates 

and relative source contributions that are protective of life-stage sensitivities. 

MDH commends the alternative approaches described in the EPA Drinking Water: Perchlorate 

Supplemental Request for Comments announcement. They show that EPA is seriously weighing all 

life stages and highly exposed sensitive subpopulations in the development of a perchlorate HRL. 

Thank you for the opportunity to comment. Please contact Kate Sande (651-201-4902) 

kate.sande@state.mn.us) with the Health Risk Assessment Section in the Environmental Health 

Division if you have any questions concerning these comments. 

Attachment: References 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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References 

Greer MA; Goodman G; Pleus RC, Greer SE. 2002. Health Effects Assessment for Environmental 

Perchlorate Contamination: The Dose Response for Inhibition of Thyroidal Radioiodine Uptake in 

Humans, Environmental Health Perspectives110(9): 927 - 937. URL: 

http://www.ehponline.org/members/2002/110p927-937greer/greer-full.html 

Minnesota Department of Health (MDH). 2008. State of Need and Reasonableness, Technical 

Support Document for the Health Risk Limit Rules for Groundwater. State of Minnesota, 

Minnesota Department of Health. URL: 

http://www.health.state.mn.us/divs/eh/risk/rules/hrlsonar08.pdf 

National Research Council (NRC). 2005. Health implications of perchlorate ingestion. The National 

Academy Press. URL: http://www.nap.edu/catalog.php?record_id=11202#toc 

U.S. EPA. 2002. A Review of the Reference Dose and Reference Concentration Process. Risk 

Assessment Forum, December 2002. URL: 

http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=55365 

U.S. EPA. 2004. Estimated Per Capita Water Ingestion and Body Weight in the United States - An 

Update Based on Data Collected by the United States Department of Agriculture's 1994-1996 and 

1998 Continuing Survey of Food Intakes by Individuals. Office of Water, and Office of Science and 

Technology, October 2004. URL: 

http://www.epa.gov/waterscience/criteria/drinking/percapita/2004.pdf 

U.S. EPA. 2005. Reference Dose for Chronic Oral Exposure (RfD) for Perchlorate and Perchlorate 

Salts. Integrated Risk Information System, February 2005. URL: 

http://www.epa.gov/iris/subst/1007.htm 

U.S. EPA. 2008a. Child-Specific Exposure Factors Handbook. National Center for Environmental 

Assessment, September 2008. URL: 

http://cfpub.epa.gov/ncea/CFM/recordisplay.cfm?deid=199243 

U.S. EPA. 2008b. Interim Drinking Water Health Advisory for Perchlorate. Health and Ecological 

Criteria Division, Office of Science and Technology, and Office of Water, December 2008. URL: 

http://www.epa.gov/ogwdw000/contaminants/unregulated/pdfs/healthadvisory_perchlo 

rate_interim.pdf 

Response: See response to comment code 5220. 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 28752 

EPA Comment Code: 5225 

 

Comment: B. Alternative HRLs Based Upon Body Weight and Water Consumption of Other Life 

Stages 4. Request for Comments a. EPA requests comment on whether the alternative HRLs 
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described in this notice appropriately take into account specific and appropriate exposure values for 

all potential sensitive life stages, including infants, children and the fetuses of pregnant women 

(rather than the 70 kg body weight and 2 liter per day consumption used for past regulatory 

determinations). 

Comment B.4.a.1: The available data do not indicate a differential effect on potentially sensitive 

subpopulations (fetuses and neonates). Consequently, alternative HRLs should not be developed for 

a postulated sensitive sub- population (fetuses and neonates). Development of alternative HRLs for 

a postulated sensitive sub-population should be predicated on reasonably rigorous scientific 

evidence demonstrating the need for such specificity. The current reference dose approach is 

generally believed to be sufficiently conservative to prevent health impacts with a margin of safety. 

We understand that the EPA does not find a need to reevaluate the current EPA-adopted RfD of 

0.7 ug/kg-day, which is a conservative and health-protective reference dose that has a 10-fold 

uncertainty factor applied to the point of departure to account for differences between healthy 

adults and the most sensitive population: fetuses of pregnant women who might have 

hypothyroidism or iodine deficiency. Therefore, the development of alternate HRLs appears 

unnecessary because the health of the most sensitive sub-population (fetuses and neonates) has 

already been considered in setting and adopting the RfD. The need for application of a second tier 

uncertainty factor has not been demonstrated by the available studies. Application of an 

appropriately calculated relative source contribution (RSC) term, as was conducted during 

development of the January 2009 Health Advisory (HA), appears adequate and appropriate. 

It is recommended that EPA support the design and collection of additional clinical data to 

determine if additional refinement of the RfD is needed to further address health protection of these 

sub-populations. 

b. EPA requests comment on the alternative HRLs in Table 2 and which of these values would be 

appropriate levels of health concern against which to compare the levels of perchlorate found in 

public water systems. 

Comment B.4.b.1: The available evidence in human populations indicates that all of the values 

identified in Table 2 are likely to be protective against adverse health effects. The NDEP notes that 

the reference dose calculation includes a 10-fold uncertainty, which was applied to the point of 

departure during development of the RfD to account for differences between healthy adults and the 

most sensitive population. NDEP believes that, based upon the currently available data, there is not 

adequate scientific basis at this time to depart from the health-protective Health Advisory level of 15 

ug/L. This health- protective value already incorporates a 10-fold uncertainty factor to account for 

differences between healthy adults and the most sensitive population: fetuses of pregnant women 

who might have hypothyroidism or iodide deficiency. 

c. EPA requests comment on whether EPA used the best available and most appropriate data to 

estimate alternative HRLs in Table 2. EPA specifically requests comment on the drinking water 

ingestion rates in Table 2 (denoted by footnote c) where the sample size does not meet the 

minimum data requirements as described in the "Third Report on Nutrition Monitoring in the 

United States" (LSRO, 1995). Does aggregate life stages (birth to 6 months, and women ages 15 - 

44) address sample size limitation and still provide an accurate representation of the exposure to the 

most vulnerable life stages? 
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Comment B.4.c.1: The fact that some of the data sets relied upon do not meet the minimum data 

requirements is one of the inherent problems in trying to regulate to a specific subpopulation rather 

than for the general population. If there was reasonably rigorous scientific evidence supporting the 

need for such special treatment to be protective against perchlorate health effects, an exception to 

minimum data requirements might be reasonable. However, the absence of such evidence, including 

considerable human data not supporting specialized sensitive receptor concerns, makes it 

inappropriate to incorporate these data for perchlorate regulation. The EPA-adopted reference dose 

of 0.7 ug/kg-day is a conservative and health-protective reference dose that has a 10-fold uncertainty 

factor applied to the point of departure to account for differences between healthy adults and the 

most sensitive population: fetuses of pregnant women who might have hypothyroidism or iodide 

deficiency. Consequently, additional adjustments to the RSC assumptions represent a second source 

of multiplicative conservatism that appear unnecessary to protect the sensitive sub-population. 

Comment B.4.c.2: Separating the data into aggregate life stages (birth to 6 months, and women ages 

15 - 44) is not necessary as it provides no discernable value in the calculation of an HRL, HA, or 

MCL. Steps such as these (separating life stages and grouping some life stages as aggregate life 

stages) might be justified if there were data demonstrating a valid concern for adverse health effects 

of perchlorate at or near the adopted Health Advisory. 

d. EPA requests comment on the merits of the approach described here of deriving HRLs for 

sensitive life stages based on the RfD combined with the life stage specific exposure data and 

whether there are other approaches that may be useful for deriving HRLs. 

Comment B.4.d.1: The merits of deriving HRLs as described in the August 19, 2009 Federal 

Register Notice include greater specificity of the risk-based calculations to the receptor population 

presumed to be of greatest concern, and perhaps reduced uncertainty in the degree of public health 

protection. However; the need for such an approach for deriving alternate HRLs for perchlorate 

that is more refined and conservative is not clearly supported by the available scientific evidence. 

Response: EPA does not believe that an HRL of 15 ug/L adequately accounts for the greater 

exposure to perchlorate on a per body weight basis that infants and developing children have in 

comparison to adults. This greater exposure is not accounted for within the RfD as the 10-fold 

uncertainty factor accounts for greater sensitivity to the same exposure, not the fact that a child is 

likely to be exposed to a greater dose on a per body weight basis. See response to comment code 

5220. Regarding the use of exposure data that meet minimum data requirements, EPA has relied on 

aggregated infant life stage data (i.e., birth to six months) that meet minimum data requirements for 

calculating the 90th percentile. EPA believes that the 90th percentile values within sensitive life 

stages appropriately account for variation in consumption on a per body weight basis and are 

protective of highly exposed individuals in these life stages. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28803 

EPA Comment Code: 5225 

 

Comment: a. Whether alternative HRLs take into account specific and appropriate exposure values 

for all potentially sensitive life stages 
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NRDC response: It is appropriate for the HRL to account for an infant's body weight, an infant's 

dietary intake and relative source contribution from water, and other contaminants that share a 

common mode of toxicity to perchlorate. 

A bodyweight assumption appropriate for an adult female does not protect fetuses, infants or 

children. For example, infants consume almost six times more water (and therefore contaminants) 

than adults, on average, in proportion to their body weight. Therefore, it would not be appropriate 

to use an adult body weight when converting a reference dose into a drinking water standard that is 

protective of infants and children. 

Many infants are breastfed for at least part of their first year of life, and perchlorate from both water 

and food does enter breast milk. Therefore, the appropriate choice for the breastfeeding scenario is 

to use an RSC value that reflects perchlorate the mother is taking in through food and drinking 

water since she is the source for the infant's breast milk. 

Response: See responses to comment codes 5210 and 5220. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28805 

EPA Comment Code: 5225 

 

Comment: b. On which of the alternative HRLs in Table 2 would be appropriate against which to 

compare levels of perchlorate in public water systems 

NRDC response: A level of perchlorate below 1 ppb is required to adequately protect vulnerable 

newborn babies and their recommended sole source of nutrition, breast milk. 

In June 2006, the State of Massachusetts Department of Environmental Protection (MA DEP) and 

its scientific advisors (MA DEP/DPH Advisory Committee) "unanimously concluded that [the 

RfD] did not fully account for the uncertainties surrounding science's understanding of perchlorate 

toxicity and exposures."[FN46: MA DEP, "Update To 'Perchlorate Toxicological Profile And 

Health Assessment'" March 2006, page xii.] Following recommendations from their scientific 

experts, MA DEP finalized an enforceable perchlorate Maximum Contaminant Level for drinking 

water and a perchlorate Cleanup Standard of 2 ppb based on a review and assessment of all data 

available at the time. Likely because the Blount (2006) data were not yet available, the MA DEP 

drinking water and cleanup standards failed to consider the special exposure patterns of infants born 

to low-iodide women, whom we now know are among the most at-risk population based on both 

high exposure and vulnerability to permanent and severe neurological impacts. Therefore, an MCL 

must be below 1 ppb to be truly health protective. 

Response: See response to comment code 5220. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0494 
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Page 466 of 1099

EPA Comment ID: 28827 

EPA Comment Code: 5225 

 

Comment: PART I 

EPA's Alternative HRL analysis. It is not clear whether EPA's new analysis resulting in new health 

reference levels (HRLs) is a one-time approach unique to perchlorate, due to a particular concern 

about certain subpopulations as noted in the 2005 National Academies of Science, National 

Research Council (NAS) report, or a new approach for determining contaminant levels that are of a 

concern for public health at various life stages based on EPA's 2005 Guidance on Selecting Age 

Groups for Monitoring and Assessing Childhood Exposures to Environmental Contaminants (2005 

Guidance) that will be applied to future regulations. 

If it is EPA's intent to apply the 2005 Guidance in this way for future regulations then EPA should 

clearly state this. AMWA also believes that the analysis should be sent to NAS for review since this 

is the first time that the 2005 Guidance has been applied in an analysis with implications for rule 

development, which would have major implications for future rulemakings. 

The analysis could be specific to perchlorate as the contaminant is unique with respect to its health 

endpoints. As suggested in the peer review document of the drinking water health advisory for 

perchlorate, "...the biological impacts of perchlorate are very different from those for chemical 

compounds which have direct target organ toxicity and/or do not directly affect the availability of 

an essential element for which homeostasis occurs." 

AMWA requests that EPA clearly explain the applicability of the alternative HRL analysis when 

issuing a final regulatory determination on perchlorate. 

In addition, if the most sensitive subpopulation is the fetus of iodide deficient pregnant women, is 

the analysis showing new HRLs for children focused on those children who are iodine deficient? 

AMWA requests that EPA make this clear in its final determination. AMWA also recommends that 

EPA should make clear in its final regulatory determination whether it still considers the fetuses of 

pregnant women who are iodine deficient to be the most sensitive subpopulation. 

Finally, AMWA asks that EPA discuss the significance of the lack of bioaccumulation of perchlorate 

in the body as noted in Greer et al., 2002 and NAS, 2005 after exposure and how this is accounted 

for in its exposure estimates in the HRL analysis. 

Response: EPA believes that alternative HRLs described in the August 2009 notice appropriately 

take into account specific and appropriate exposure values for infants, children and the fetuses of 

pregnant women (rather than the 70 kg body weight and 2 liter per day consumption used for past 

regulatory determinations). This analysis is applicable to perchlorate because individuals at these life 

stages are particularly sensitive to the effects of perchlorate. 

EPA will consider using life stage specific exposure factors where the best available science indicates 

life stages are particulary sensitive. 

EPA's analysis of HRLs does not assume bioaccumulation of perchlorate. 
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Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28830 

EPA Comment Code: 5225 

 

Comment: NOEL vs. NOAEL 

The 2005 National Research Council report recommended an RfD of 0.0007 mg/kg by employing 

two margins of safety. The first was to use the point of departure as a conservative NOEL vs. a 

NOAEL. In addition, the report recommended applying an additional factor of 10 to protect all 

sensitive groups, including the fetuses of pregnant women with iodine deficiency and children and 

infants. 

AMWA asks that EPA clearly explain the significance of the NOEL vs. NOAEL in the alternative 

analysis of HRLs, as it appears that the agency is compounding safety factors that already account 

for the sensitivity and variability between population groups. 

Response: EPA has clearly and consistently explained the basis of departure for the perchlorate 

RfD using the NRC report language. 

EPA does not believe that accounting for specific and appropriate exposure values for all potentially 

sensitive life stages, including infants, children and the fetuses of pregnant women "compounds," or 

"double-counts," the uncertainty factor that has already been applied. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28836 

EPA Comment Code: 5225 

 

Comment: 74 FR 41889: "EPA specifically requests comment on the drinking water ingestion rates 

in Table 2 where the sample size does not meet the minimum data requirements as described in the 

"Third Report on Nutrition Monitoring in the United States (LRSO, 1995)." 

Response: AMWA believes that if the sample sizes for estimates of ingestion rates in Table 2 do not 

meet minimum data requirements set forth in CDC's LRSO, then they should not be used for HRL 

development that could be used as a basis for national policy. 

Response: As EPA states in the August 2009 notice, for six life stages in Table 2 (birth to < 1 

month, 1 to < 3 months, 3 to < 6 months, 16 to 18 years and 18 to 21 years and for pregnant 

women), the sample size used to estimate some of the drinking water ingestion rates (denoted in 

Table 2 by foot note "c") do not meet the minimum data requirements as described in the "Third 

Report on Nutrition Monitoring in the United States." However, these are the best available data to 

characterize drinking water ingestion for these specific life stages. EPA also notes that these data 

clearly show the trend that drinking water mean ingestion rate on a per body weight basis increases 

as the life stage age decreases. Although the approach may have shortcomings, EPA 
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interpolations/extrapolations are reasonable and in accordance sound and objective scientific 

practices. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28840 

EPA Comment Code: 5225 

 

Comment: In closing, AMWA again urges EPA to have the alternative HRL and PBPK analysis 

reviewed as it is a new analysis that was developed by applying for the first time the 2005 Guidance. 

The potential precedent that will be set if these analyses are used in rulemaking will have significant 

ramifications for how future drinking water policy is developed. In addition, AMWA recommends 

that EPA consider all available science as well as the most recent occurrence data as it prepares its 

final regulatory decision. 

If you have any questions about these comments, please contact me or Erica Brown, Director of 

Regulatory Affairs and Scientific Program Development at 202-331-2820 or via email: 

brown@amwa.net. 

Sincerely, 

 Diane VanDe Hei Executive Director Cc: Peter Silva, OW Cynthia Doughtery, OGWDW Eric 

Burneson, OGWDW Attachment [see PDF docket ID EPA-HQ-OW-2009-0297-0494] 

Response: EPA has evaluated the available science to inform the regulatory determination. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0415 

EPA Comment ID: 28843 

EPA Comment Code: 5225 

 

Comment: Interpretation of the Physiologically-Based Pharmacokinetic (PBPK) Modeling 

AWWA recognizes the value of using models for risk assessment purposes. The Agency, in response 

to concerns raised in October 2008, elected to reassess exposure to life stages and broaden the scope 

of "the most sensitive population" which previously had been defined by the National Research 

Council (2005) as "the fetuses of pregnant women who might have hypothyroidism or iodine 

deficiency." The assessment appropriately follows EPA's Guidance on Selecting Age Groups for 

Monitoring and Assessing Childhood Exposures to Environmental Contaminants (USEPA, 2005) 

which recommends the following 10 age groups be considered in exposure assessments for children. 

- Less than 12 Months old: birth to < 1 month, 1 to < 3 months, 3 to < 6 months and 6 to < 12 

months. - Greater than 12 months old: 1 to < 2 years, 2 to < 3 years, 3 to < 6 years, 6 to < 11 years, 

11 to < 16 years, and 16 to < 21 years. 

AWWA recognizes these important subpopulations, yet is troubled by the lack of recognition in the 

modeling efforts to incorporate the findings from the most recent and well designed epidemiological 
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studies. These studies provide direct dose-response assessments that should be included into the 

Agency's modeling effort rather than making presumptive calculations for purposes of estimating a 

Health Reference Level (HRL) for each life stage examined. The majority of these studies have 

shown no adverse health effects to women of child bearing age, newborns, and school age children 

who were exposed to significant amounts of perchlorate via drinking water at levels below and 

above the EPA accepted Reference Dose (RfD) of 0.0007 mg/Kg-day), as well as to other 

goitrogens. These studies also address the request for comment regarding the use of the PBPK 

model to "explore the relative sensitivity of various life stages". 

Response: See response to comment ID 28338 under comment code 5225. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0415 

EPA Comment ID: 28845 

EPA Comment Code: 5225 

 

Comment: Alternative HRLs Based Upon Body Weight and Water Consumption of Other Life 

Stages 

AWWA believes that it is unnecessary for the Agency to adjust for Relative Source Contribution 

(RSC) when calculating a HRL, since the RfD is based on a No Observed Effects Level (NOEL) 

and the Greer [FN7: Greer, M., Goodman, G., Pleus, R., and Greer, S. 2002. Health effects 

assessment for environmental perchlorate contamination: the dose-response for inhibition of 

thyroidal radioiodine uptake in humans. Environmental Health Perspectives, 110:927.] study only 

measured the incremental exposure to drinking water. The body of data on which the National 

Research Council (NRC) based their conclusions produced a No Observed Effects Level (NOEL) 

(not considered a No Observed Adverse Effects Level [NOAEL]because the biochemical changes 

measured were not considered adverse in and of themselves) of 0.007 mg/Kg-day. The NRC further 

recommended a total uncertainty factor of 10 for intraspecies extrapolation (the data were from 

humans), resulting in a recommended RfD of: 

RfD = 0.007 / 10 = 0.0007 mg/Kg-day 

The Agency [FN8: USEPA. 2005. EPA Sets Reference Dose for Perchlorate. New release dated 

02/18/2005. 

http://yosemite.epa.gov/opa/admpress.nsf/b1ab9f485b098972852562e7004dc686/c1a57d 

2077c4bfda85256fac0 05b8b32!OpenDocument] accepted the NRC's RfD. Typically the RfD would 

be multiplied by the RSC for ingestion of drinking water to obtain a limit on exposure. However, 

this practice arose from the common use of clinical, epidemiological, or experimental animal studies 

in which individuals were exposed solely through the route of interest (e.g. ingestion of water). 

Given a sole route of exposure it is necessary to correct for the fact that individuals in the general 

population would likely be exposed to a compound through multiple routes. As a result, the 

application of an RSC in the regulatory process is based on the (often unstated, but nonetheless 

implicit) assumption that the study population was NOT exposed through routes other than the one 

of interest, while the general population was exposed through ALL routes. 
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This assumption is not fully warranted in the case of perchlorate because the individuals in the 

Greer study maintained a normal diet during the period of the study.[FN9: Crawford-Brown, D., 

Raucher, B., and M. Herrod 2006. Inter-Subject variability of risk from perchlorate in community 

water supplies. Environmental Health Perspectives, 114:7:975.] Therefore, they should have been 

exposed to perchlorate from non-drinking-water routes at an Average Daily Rate of Intake (ADRI) 

value roughly equivalent to that of the general population that is the target of regulatory 

determinations. This is supported by the FDA's Total Diet Study [FN10: Murray, C.W III, S.K. 

Egan, H. Kim, N. Beru, P.M. Bolger. 2008. US Food and Drug Administration's Total Diet Study: 

Dietary Intake of Perchlorate and Iodine. Journal of Exposure Science and Environmental 

Epidemiology 18:571.] and the NHANES assessments [FN11: Blount, B.C., J.L. Pirkle, J.D. 

Osterloh, L. Valentín-Blasini, and K.L. Caldwell. 2006. Urinary perchlorate and thyroid hormone 

levels in adolescent and adult men and women living in the United States. Environmental Health 

Perspectives. 114:12:1865.],[FN12: Blount, B.C., L. Valentin-Blasini, J.D. Osterloh, J.P. Mauldin, and 

J.L. Pirkle. 2007. Perchlorate Exposure of the US Population, 2001-2002. Journal of Exposure 

Science and Environmental Epidemiology 17:400.], which suggests a ubiquitous exposure to 

perchlorate from various food sources. If this is the case, application of an RSC would in effect 

"double count" the influence of the non- drinking-water exposures, because the NOEL from the 

Greer study already reflected these background exposures (absent these background exposures, the 

NOEL of 0.007 mg/Kg-day would be expected to be higher). 

Since the RfD is based on a NOEL versus the traditional NOAEL, EPA is already building in extra 

levels of protection. The current request for comments recognizes that this is a departure from the 

traditional approach and that the NOEL which is based on "using a nonadverse effect that is 

upstream of the adverse effect is a more conservative and health protective approach". The NRC's 

use of a precursor to an adverse effect is represented in Figure 1. The RfD represents a point of 

departure (POD) that precedes the inhibition of iodine uptake by the thyroid. 

Figure 2 provides a generic representation of the difference between the NOEL and NOAEL. 

Given the very conservative and precautionary nature of the RfD, further adjustment of the RfD as 

suggested by the Agency for purposes of recommending HRLs is unwarranted. This is further 

supported by the epidemiological studies that cover multiple life stages at perchlorate levels above 

and below the suggested HRLs and observed no adverse effects. 

Figure 1. Depiction of Point of Departure (POD) used to derive NOEL [see PDF docket ID EPAHQ-OW-2009-0297-0415] 

Figure 2. Perchlorate RfD represents a conservative point of departure (POD) for hazard 

assessment [see PDF docket ID EPA-HQ-OW-2009-0297-0415] 

Response: See response to comment code 5210. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection (MassDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0495 

EPA Comment ID: 28862 

EPA Comment Code: 5225 

 
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Comment: 4) MassDEP supports setting the HRL on the basis of the life stage(s) with highest 

exposure and risk with a 90% percentile ingestion rate, which is standard practice. Based on Table 2, 

this would support an HRL of 2 ppb (or perhaps somewhat lower depending on the exposure 

estimate for the 7-day old). It is worthwhile to note that the alternative HRLs calculated using the 

95th percentile exposure values for early life stages are not very different than the HRL values 

estimated using the 90th percentile ingestion rates, especially considering the rounding involved in 

the final calculation of the HRLs. Although EPA's concern about sample size and aggregation of life 

stages is legitimate, the aggregation of life stages in the current document (birth to < 6 months) yield 

closely similar HRL values derived for life stages birth to < 1 month, 1 to < 3 months, and 3 < 6 

months and birth < 6 months and therefore appear to be reasonably stable estimates (Table 2). 

Response: See response to comment code 5220. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection (MassDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0495 

EPA Comment ID: 28864 

EPA Comment Code: 5225 

 

Comment: 6) We believe that EPA has used the best available exposure data for deriving the HRLs. 

Use of the 90% percentile ingestion rate addresses uncertainties regarding the issue of minimum 

data set deficiencies for ingestion rates. 

Response: EPA has selected HRLs based on the 90th percentile ingestion rates as a basis for the 

final regulatory determination. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28869 

EPA Comment Code: 5225 

 

Comment: 2. Derivation of alternative Health Reference Levels (HRLs) based upon body weight 

and water consumption rates for sensitive life stages: The alternative HRL calculation which relies 

on life-stage specific body weight and water consumption rates is not scientifically justified. 

Authoritative bodies (e.g., NRC, EPA, the Agency for Toxic Substances and Disease Registry, the 

California Environmental Protection Agency Office of Environmental Health Hazard Assessment 

(OEHHA)) have conducted rigorous scientific assessments and have determined that the fetus of 

the hypothyroid pregnant woman is the most sensitive to perchlorate's potential health effects, not 

the infant as suggested by the alternative HRL calculation. The Notice provides no scientific 

evidence that shows otherwise and offers no justification for basing a HRL on an alternative 

population that is not the most sensitive. Further, the values given in the Notice for specific 

exposure assumptions do not meet the Agency's own guidelines for data quality. 

Response: See response to comment ID 28752 under comment code 5225 for a discussion of 

considering life stage specific exposure data in calculating HRLs. 
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Regarding the comment that the values given in the notice for specific exposure assumptions do not 

meet the Agency's own guidelines for data quality, see response to comment ID 28836 under 

comment code 5225. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28879 

EPA Comment Code: 5225 

 

Comment: II. RESPONSES TO REQUEST FOR COMMENTS ON ALTERNATIVE 

APPROACHES TO ANALYZING SCIENTIFIC DATA RELATED TO PERCHLORATE IN 

DRINKING WATER 

Compared to the EPA PBPK model, the alternative HRLs listed in the Notice are not scientifically 

rigorous. 

The Agency's process is not transparent in how it might use any of the three alternative approaches 

described in the Notice to revise its regulatory determination for perchlorate. For example, the 

Notice does not remark if it intends to use both the PBPK model and the HRL "model." Further, 

the Notice is not clear about how the Agency intends to integrate the results of these alternative 

approaches with existing knowledge about the threshold for IUI in average adults. 

The comments in this document assume EPA does not intend to apply both the PBPK model and 

alternative HRLs based on body weight and water consumption. Further, this document assumes 

that EPA seeks input on whether one approach is scientifically more accurate than the other for 

extrapolating from a no effect dose measured in adults to sensitive subpopulations. Overall, the 

scientific community supports the use of PBPK modeling when all parameters are based on 

scientific experiments (Mager et al., 2003). When scientifically validated, PBPK models can be useful 

to reduce uncertainty about sensitive life stages. In contrast and as will be discussed below, the 

HRLs based on body weights and water consumption rates do not reflect a similar scientific basis. 

It is important to note the difference between the results in Table 1 of the Notice (which presents 

the PBPK model-predicted RAIU inhibition for each life stage) and Table 2 (which presents the 

alternative HRLs based on body weight and water consumption). The RAIU inhibition estimates in 

Table 1 were computed using a dose of 0.007 mg/kg-d, the Greer et al. (2002) POD. This dose is 

equivalent to 245 ppb of perchlorate in drinking water if one uses standard EPA default values for 

body weight and drinking water consumption.[FN7: 0.007 mg/kg-d x (70 kg adult / drinking 2 L of 

water per day = 0.245 mg/L or 0.245 ppm or 245 ppb.] The HRLs in Table 2 are based on the 

perchlorate RfD which is ten times lower, i.e., 0.0007 mg/kg-d or 24.5 ppb. Therefore, anyone 

comparing Tables 1 and 2 should recognize a 10-fold difference in the underlying dose assumptions. 

For example, the highest RAIU inhibition reported in Table 1 is 12.5% for the lactating woman and 

breast-fed infant exposed to a dose of 0.007 mg/kg-d. At the 10-fold lower RfD in Table 2, the 

RAIU inhibition for the lactating woman and breast-fed infant would be approximately 2%, a value 

that would not be significantly different from normal fluctuations because of differences in diet and 

feeding styles. There is no credible scientific evidence that this effect has any biological significance. 
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Based on the EPA PBPK model, at the RfD, the RAIU inhibition for the exclusively breast-fed 

infant would be approximately 2%, a value that would not be significantly different from normal 

fluctuations due to diet. 

Response: EPA was transparent in our August 2009 discussion of how we might consider the 

alternative HRLs in lieu of the single HRL of 15 ug/L used for the October 2008 notice. The agency 

was also clear that we were reconsidering our application of the PBPK model in light of how the 

comments we had received from both our peer reviewers and the commentors on the notice. See 

response to comment ID 28923 under comment code 2400 for a discussion of our decision not to 

use the PBPK modeling to inform the final regulatory determination. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28886 

EPA Comment Code: 5225 

 

Comment: B. Derivation of Alternative HRLs Based on Body Weight and Water Consumption 

Rates for Sensitive Life Stases 

The NRC panel and subsequent studies consistently identify the fetus as the most sensitive 

population for perchlorate health effects evaluation. 

In October 2008, EPA calculated an HRL for perchlorate in drinking water based on the RfD and a 

RSC of 62%, and EPA's default body weight and water consumption rates for an adult (U.S. EPA, 

2008a). Based on a comment regarding the adequacy of EPA's proposed HRL to be protective of 

sensitive life stages, EPA presented an alternative calculation of an HRL in the Notice based on 

weight-normalized water intakes for specific life stages.[FN13: For example, EPA says, "One 

commenter cites a March 8, 2006, letter from the Children's Health Protection Advisory Committee 

to the EPA Administrator. The commenter states, "[T]he committee emphasized the higher 

exposure of infants to perchlorate and greater susceptibility to serious negative effects associated 

with perchlorate exposure. Neither of these issues, however, was given adequate consideration in the 

Preliminary Determination."] EPA has not presented any scientific evidence for why its proposed 

HRL in October 2008 was inadequate to protect other life stages or why it would be necessary to 

add additional safety factors to the RfD in the form of life stage-specific intake rates. In contrast to 

the PBPK model, the alternative HRL approach: 

* is based primarily on one variable (the water intake rate); 

* uses data that are not derived from scientific experiments but from a summary obtained in a 

survey that relies on subject recall rather than direct measurement; 

* relies on methods that are incapable of measuring, estimating, or predicting the effects of a 

chemical on the body; and 

* produces results that are qualitative at best. 
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In summary, determining the most sensitive life stages based on water consumption rates implicitly 

makes general assumptions about numerous body functions in lieu of actual scientific data about 

physiological differences between these population groups. This "model" does not account for 

absorption, distribution, or excretion, regardless of the individual's state of development. It 

implicitly assumes that the potential for exposure is directly proportional to body weight, without 

scientific supporting data. 

PBPK modeling provides a more scientifically defensible approach to characterize the relative 

sensitivity of different life stages to perchlorate exposure. The Notice's alternative HRL calculations 

are insensitive, duplicative, and not scientifically warranted. 

The Notice should be transparent that the alternative HRL calculation it presents is an arithmetic 

calculation based on only three variables: the RfD, an RSC, and life stage specific water intake rates. 

Of these, the only scientifically defensible value is that upon which the RfD is based- the POD 

derived from Greer et al. (2002). The RSC is based on the mean intake of perchlorate from the Food 

and Drug Administration (FDA) Total Diet Study for the nearest age range, and the 90th percentile 

intake from a NHANES-UCMR analysis for pregnant women and women ages 15-44 that was 

conducted for preliminary regulatory determination. Using the 90th percentile is a not a sciencedriven decision. The water intake by body weight is arbitrarily categorized by age (i.e., what is 

physiologically unique about 6 months of age versus 5 months of age?). Further, the consumption 

values for the infant are based on a study in which the study participant had to recall their own (or 

their infant's) consumption over two non-consecutive days; no direct measurements were taken. 

Recall studies are subject to error (called recall bias) from lapses in memory on estimations of 

amounts consumed (i.e., what, when, and how much did I eat or drink?). In addition, the population 

size in this study does not meet EPA's data quality standards. 

The EPA has asked for comment on four general questions regarding the Notice's alternative HRL 

calculations. Responses to these questions, based on the best available scientific information, follow. 

1. EPA requests comment on whether the alternative HRLs described in this notice appropriately 

take into account specific and appropriate exposure values for all potentially sensitive life stages, 

including infants, children and the fetuses of pregnant women (rather than the 70 kg body weight 

and 2 liter per day consumption used for past regulatory determinations). 

The HRL methodology that the Notice describes does not appropriately account for sensitive life 

stages for several reasons: (1) the most sensitive population has already been considered in the 

perchlorate RfD; (2) EPA provides no scientific justification for why this alternative HRL is 

necessary; and (3) there are no scientific data that meet EPA data quality requirements to 

substantiate the calculations used to develop these HRLs. 

Response: The NRC (2005) identified "the fetuses of pregnant women who might have 

hypothyroidism or iodide deficiency" as "the most sensitive population," but also identified infants 

and developing children as additional "sensitive populations." Infants and young children have 

greater exposure to contaminants in food and water because of greater consumption of food and 

water on a per unit body weight basis. Therefore, these life stages may be the most vulnerable 

populations when their relative exposure is considered. Therefore, EPA used this approach to derive 

HRLs by evaluating exposures at different life stages. See response to comment ID 28752 under 

comment code 5225 for more discussion. 
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EPA believes that data to evaluate drinking water consumption on a per body weight basis are 

critical for comparison to the RfD for perchlorate. EPA further believes that the exposure data used 

by the Agency are the best available peer reviewed data. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28888 

EPA Comment Code: 5225 

 

Comment: The historic standard procedure for converting the RfD into drinking water equivalent 

levels (DWELs) assumes 2 liters (67.6 oz) per day of water consumption and a body weight of 70 kg 

(154 lbs). One important purpose of converting the RfD (in units of mg/kg-day) to a DWEL (in 

units of ug/L or ppb) is to make it easy to compare water concentrations of contaminants to 

government guidelines. In doing so, EPA conservatively opts for higher than average intake and 

lower than average body weight. Thus, these default values are not symmetrically representative of 

the population. The water consumption (2 liters) default is approximately equal to the 88th 

percentile water intake for adults aged 20 through 64 (U.S. EPA, 1997). The default body weight of 

70 kg is approximately equal to the 27th percentile of the distribution for adult males aged 18-74 and 

the 70th percentile of the distribution for adult females (U.S. EPA, 1997). Because the conversion 

uses the ratio of body weight to water intake, the use of lower percentiles in the numerator than are 

used in the denominator leads to a biased overestimate of the dose. 

The DWEL is based on the RfD. The RfD is defined as (NRC, 2005): 

...an estimate (with uncertainty spanning perhaps an order of magnitude) of a daily oral exposure to 

the human population (including sensitive subgroups) that is likely to be without risk of deleterious 

effects during a lifetime. It can be derived from a NOAEL, LOAEL, or BMD, with UFs generally 

applied to reflect limitations of the data used. 

Therefore, by definition, the RfD already accounts for the most sensitive population and lifetime 

exposures. In the most recent review of the RfD process, the EPA technical committee 

recommended (U.S. EPA, 2002): 

The intraspecies UF is applied to account for variations in susceptibility within the human 

population (interhuman variability) and the possibility (given a lack of relevant data) that the 

database available is not representative of the dose/exposure-response relationship in the subgroups 

of the human population that are most sensitive to the health hazards of the chemical being 

assessed. As the reference concentration/dose is defined to be applicable to "susceptible 

subgroups," this UF was established to account for uncertainty in that regard. 

EPA remarks that additional factors should not be applied to determine a MCLG. For example, in 

the Disinfectant and Disinfection Byproduct rule (enacted during the Clinton Administration), EPA 

rejected additional safety factors for children or adjusting the default adult bodyweight/consumption parameters: 
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EPA disagrees that an additional safety factor should be applied to provide additional protection for 

children or that drinking water consumption relative to body weight of children should be used in 

developing the MCLG (maximum contaminant limit goal). The MCLG presented for chlorite and 

chlorine dioxide are considered to be protective of susceptible groups, including children, given that 

the RfD is based on a NOAEL derived from developmental testing. Additionally, current methods 

for developing RfDs are designed to be protective for sensitive populations. The 2 liter per day 

water consumption and the 70 kg body weight assumptions are viewed as adequately protective of 

all groups (U.S. EPA, 1998b). 

Lifetime exposure includes exposure during infancy. An RfD that failed to account for exposure 

during infancy would fail to satisfy the standard definition. Applying life stage specific drinking 

water values would, in effect, "double count" the UF that has already been applied. 

EPA requests comment on the alternative HRLs in Table 2 and which of these values would be 

appropriate levels of health concern against which to compare the levels of perchlorate found in 

public water systems. 

The calculated values presented in Table 2 are not scientifically justified. Although this table presents 

levels that have been found in public water systems, there is no health effect associated with the 

values presented. In fact, every life stage calculation in Table 2 corresponds to a no effect level, 

based on IUI which is a fully reversible, nonadverse effect that occurs on a routine and daily basis. 

The NRC noted that the dose at which perchlorate might cause hypothyroidism is greater than 0.4 

mg/kg-d (14,000 ppb using default drinking water and body weight conversions). It states (NRC, 

2005): 

On the basis of the studies of long-term treatment of hyperthyroidism in which patients continued 

to be given perchlorate after their hyperthyroidism resolved and the clinical studies of healthy adults, 

the perchlorate dose required to cause hypothyroidism in adults would probably be more than 0.40 

mg/kg per day, assuming a 70-kg body weight. 

Importantly, the NRC (2005) also emphasizes: 

The committee emphasizes that inhibition of iodide uptake by the thyroid has been the only 

consistently documented effect of perchlorate exposure in humans. The continuum of possible 

effects of iodide-uptake inhibition caused by perchlorate exposure is only proposed and has not 

been demonstrated in humans exposed to perchlorate (with the exception that in patients with 

hyperthyroidism doses of 200 mg daily or higher may reduce thyroid secretion). 

The PBPK results, as presented in Table 1 of the Notice, show the 1 week old breastfeeding infant 

to have the greatest RAIU inhibition when its mother is given a dose 10 times greater than the RfD 

(e.g., exposure at water concentration of 245 ppb). This assumes that the infant would be exclusively 

breastfed. In calculating the HRL, the age groups that had the greatest intake per body weight, 

however, were the youngest infants who are exclusively formula fed. Based on the PBPK model, the 

bottle fed infant had a 1.5% change in RAIU inhibition, which is well within the normal variation of 

RAIU inhibition. 
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2. EPA requests comment on whether EPA used the best available and most appropriate data to 

estimate alternative HRLs in Table 2 (denoted by footnote c) where the sample size does not meet 

the minimum data requirements as described in the "Third Report on Nutrition Monitoring in the 

United States" (LSRO, 1995). Does aggregating life stages (birth to 6 months, and women ages 15-

44) address sample size limitation and still provide an accurate representation of the exposure to the 

most vulnerable life stages? 

The drinking water intake rates in the age groups are based on USDA Continuing Study of Food 

Intakes by Individuals from 1994-1996 and 1998. This was a large study of dietary recall and was 

reported by Kahn and Stralka (2008). Although this may be the best study that the Agency could 

find, it is neither sufficient nor does it meet the scientific standards the EPA's own guidelines 

demand for a regulatory process. 

First, compared to the science-based data used in a PBPK model, water intake is an insensitive 

variable. It cannot be used for measuring, estimating, or predicting the effects of a chemical on the 

body. In fact, it does not and cannot estimate or predict any effects in the body. This study is not 

based on a specific experiment, but a summary of data obtained in a survey based on recall rather 

than direct measurements. The best and most scientific process would be to measure and record the 

exact amount of fluid or food intake at the time of ingestion. 

Second, as noted by EPA in the Notice, for some life stages, the data do not meet EPA guidelines 

on data quality.[FN14: The Notice states "The sample sizes for the estimates of ingestion rates for 

these life stages do not meet the minimum data requirements as described in the "Third Report on 

Nutrition Monitoring in the United States" (LSRO, 1995)."] Water intake as the sole variable makes 

general assumptions about numerous body functions in lieu of actual data. For example, in effect, 

this calculation does not account for absorption, distribution, or excretion, regardless of 

developmental state. This calculation implicitly assumes that the body's disposition of perchlorate is 

directly proportional to body weight. There are no scientific data to support these assumptions. 

Third, the study population in Kahn and Stralka (2008) may not be representative of the U.S. 

population. The body weights presented by Kahn and Stralka (2008) are lower than that found in 

1996-2000 NHANES data, as presented by EPA in the Child Specific Exposure Factors Handbook 

(U.S. EPA, 2008d) and may not be representative of the general population. For one month olds, 

the Kahn and Stralka (2008) mean, 90th and 95th percentile body weights are 20, 45, and 24% lower 

than the NHANES 1996-2000 data. A greater body weight will result in a lower total dose, if intake 

is the same. The comparison body weights for the three youngest age groups are presented in Table 

1 in Appendix A. 

Fourth, Kahn and Stralka (2008) is a recall study. As noted above, this is a study in which the study 

participant had to recall their own (or their infant's) consumption over two non-consecutive days. 

No direct measurements were taken. Recall studies are subject to bias from errors in memory when 

recalling the amounts consumed (i.e., what, when, and how much did I eat or drink?). For example, 

it is possible and not unusual that the person reporting the infant intake estimated a high value for 

intake. If this occurred for one or two individuals in the study, the data would be skewed (as 

observed by inspection), overestimating the statistical estimation of the 90th and 95th percentile 

water consumption values. 
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Applying life stage specific drinking water values is, in effect, "double counting" the uncertainty 

factor that has already been applied. 

Furthermore, a dietary recall study should represent the entire population, not just tap water 

consumers. The water intake from Kahn and Stralka (2008) were calculated based on individual 

parameters. EPA chose to use the data for consumers of water only, yet individuals commonly use 

water from other sources (e.g., bottled, in juice or soda). Since the EPA is interested in developing a 

MCL, sources of water that would be regulated are municipal water systems. One effect of choosing 

not to use the analysis of all individuals is that the results are higher than what would be reflected if 

all data were used. That is to say, this would not be a science-based decision. The results of using 

ingestion rates from consumer versus all individuals on the alternative HRLs are presented in Table 

2 in Appendix A. To illustrate the effect noted above of limiting the population, in infants less than 

one month of age, the proposed alternative HAL based on consumers only was 3 ug/L; if the value 

for all individuals is used, the water concentration would be 8 ug/L. 

EPA reports intake rates and alternative HRLs based on the mean, 90th, and 95th percentiles. Kahn 

and Stralka (2008) lack sufficient study size and methodology to reliably inform the science related 

to the general population, as the Notice acknowledges. 

One way to gauge whether the 90th and 95th percentile values suggested in the Notice are 

statistically unreliable is a simple comparison to blood volume. The average adult has a blood 

volume of approximately 5 L and drinks approximately 1.4 L/d, or 27% of their blood volume (U.S. 

EPA, 1997). It is well understood that infants and children consume more than adults when 

normalized for body weight, but using the intake rates suggested by EPA, the 95th percentile one 

month old infant would consume 2.6 L/d or 280% of their blood volume. This is the equivalent of 

the average adult consuming just under 4 gallons, every day. Comparisons of water intake to blood 

volume are presented in Appendix A, Table 3. 

The RfD is based on the study by Greer et al. (2002) and the researchers in this study did not 

control dietary intake of perchlorate or other natural agents such as nitrate, thiocyanate, or iodine. 

Perchlorate has been detected in many foods, including but not limited to milk, lettuce, and 

cantaloupe (Murray et al., 2008). No perchlorate was reported detected in Portland's city water 

supply (the location of the study) according to UCMR1. Thus, assuming that Murray et al, (2008), is 

correct, subjects would have received perchlorate from food (See Figure 1). Therefore, the dose of 

perchlorate that resulted in a NOEL was in addition to the background level of perchlorate ingested 

through food. If the background dose of perchlorate from all sources was 0.02 to 0.234 ug/kg-d (the 

5th and 95th percentile estimated doses from Blount et al. (2007)), then all doses in Greer et al. 

(2002) underestimate the true dose by this amount and the RSC has already been considered. 

Figure 1. Visual representation of UF, the RfD, and unaccounted for contribution of perchlorate in 

food are components of the POD dose. [see PDF docket ID EPA- HQ-OW-2009-0297-0662] 

3. EPA requests comment on the merits of the approach described here of deriving HRLs for 

sensitive life stages based on the RfD combined with the life stage specific exposure data and 

whether there are other approaches that may be useful for deriving HRLs. 

Given the strength of the underlying science in the EPA PBPK model, the proposed HRLs in the 

Notice do not address sensitive life stages in a scientifically justified manner. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Some have suggested that perchlorate should be regulated differently because its acute effects may 

be detrimental during sensitive life stages. This assumes that the UF applied to the RfD is not large 

enough to account for the most sensitive life stage. Such a claim would be not supported by 

scientific evidence. First, toxicologically speaking, an acute effect is an effect seen after one high 

dose or an exposure of less than 24 hours. No published study has demonstrated an effect after one 

exposure to perchlorate at environmental levels. Even if acute is meant to refer to effects over 

several weeks to months (more commonly termed "subchronic") of exposure, no study 

demonstrates adverse effects at environmental levels, nor would an effect be expected based on the 

current scientific literature. As the Greer et al. (2002) study demonstrated, any IUI at the POD dose 

is within normal variation and there is no evidence that any effects, much less any adverse effects, 

would be expected at doses near the RfD, on a short-term or chronic (lifetime) basis. 

Response: See response to comment ID 28752 under comment code 5225 for a discussion of the 

use of life stage specific exposure values for determining HRLs. See response to comment code 

5210 for a discussion of the relative source contribution. See response to comment ID 28338 under 

comment code 5225 for a discussion of the health implications of exposure above the RfD. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28903 

EPA Comment Code: 5225 

 

Comment: 2. The proposed use of alternative HRLs based upon body weight and water 

consumption of other life stages is not a scientifically-based process. If there were a lack of data for 

a particular chemical, then perhaps this approach would be defensible. For perchlorate, however, 

where the effort of scientists to reduce uncertainty has been long standing and focused, the use of 

body weight and water consumption would increase uncertainty. The PBPK modeling provides 

greater and more biologically significant information. 

Response: See response to comment ID 20432 under comment code 5220 for a discussion of 

EPA's decision regarding the use of the PBPK model in the regulatory determination. 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0527 

EPA Comment ID: 28911 

EPA Comment Code: 5225 

 

Comment: Alternative HRLs Based Upon Body Weight and Water Consumption of Other Life 

Stages 

In the October 10, 2008 notice, the proposed Health Reference Level (HRL) for perchlorate of 15 

ug/L was derived using exposure assumptions for a pregnant woman/fetus exposed to the RfD of 

0.7 ug/kg/day with a Relative Source Contribution (RSC) factor of 0.6. In developing this HRL, 

USEPA assumed that the fetus is the most sensitive subpopulation, more sensitive than the infant, 

so that the infant could be safely exposed to much higher doses than the fetus. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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We strongly disagree with the assumption that exposure of infants to perchlorate above the 

Reference Dose is acceptable. We urge USEPA to use exposure assumptions for all potentially 

sensitive life stages, especially infants and children, to derive alternative HRLs that are protective of 

all sensitive subgroups. A similar approach that considers exposure assumptions for infants was used 

by the NJDWQI (2005) in developing its recommendation for a perchlorate MCL, and by NJDEP 

(2009) in developing its MCL proposal. We strongly support USEPA's approach based on 

combining the RfD, which is intended to protect sensitive subpopulations, with exposure data 

specific for sensitive life stages such as infants. We do not advocate other approaches for deriving 

HRLs. 

Response: See response to comment code 5220. 

Commenter Name: Danielle Blacet 

Commenter Organization: Association of California Water Agencies 

EPA Document ID: EPA-HQ-OW-2009-0297-0208 

EPA Comment ID: 28924 

EPA Comment Code: 5225 

 

Comment: 2) Alternative Health Reference Levels (page 41889) 

ACWA has reviewed the table referenced in the request for comments and we believe that an 

educated answer is not feasible as the various levels are not based on science connecting exposure to 

any actual observed adverse health effect. We encourage USEPA to seek out or initiate studies that 

may better inform such a significant dataset. 

Response: See response to comment code 5220. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group (EWG) 

EPA Document ID: EPA-HQ-OW-2009-0297-0499 

EPA Comment ID: 28929 

EPA Comment Code: 5225 

 

Comment: On August 19, the agency published a notice in the Federal Register seeking comments 

on its additional approaches to analyzing data related to its perchlorate regulatory determination. 

These new approaches differ from EPA's prior assessment primarily because they focus on the risks 

of perchlorate exposure to infants and children, as opposed to the prior assessment that focused on 

risks to the fetus of the hypothyroid or iodide-deficient woman. EWG fully supports these 

approaches. Although fetal development is a highly vulnerable life stage for perchlorate exposure, 

research from the last several years has confirmed that infants and children are an equally high-risk 

population group due to their small size relative to adults and their high level of perchlorate 

exposure via water and food. 

Response: See response to comment code 5220. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group (EWG) 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Document ID: EPA-HQ-OW-2009-0297-0499 

EPA Comment ID: 28931 

EPA Comment Code: 5225 

 

Comment: Appropriateness of alternative HRLs: EWG supports the alternative HRLs if they are 

modified to reflect risks to infants from widespread perchlorate contamination of powdered infant 

formula and if infants under six months of age are not aggregated in the agency's exposure 

assessment. 

Further in its assessment, the agency also lists a number of new Health Reference Levels (HRLs) as 

an alternative to its proposed HRL of 15 ppb from December, 2008. The agency derived these new 

HRLs by evaluating exposure to perchlorate at different life stages. In Table 2 of the notice, the 

Agency lists HRLs for 14 different life stages at three different drinking water ingestion rates 

(average, 90th, and 95th percentile). 

Ten of the life stages are for children 16 years old or younger, indicating the Agency's recognition 

that perchlorate exposures vary during each stage of childhood. 

For drinking water ingestion rates at the 90th and 95th percentile rates for infants in the three 

youngest life stages, the Agency notes that the sample sizes for the estimates of ingestion rates do 

not meet established minimum data requirements. The actual sample sizes for these three groups are 

37 (birth to <1 month), 108 (1 to < 3 months), and 269 (3 to <6 months). While they may not meet 

minimum data requirements, EWG strongly supports their use because these are the best data 

available (EPA 2008), and because aggregating these age groups masks significant exposure 

disparities in these critical life stages. 

Infants in the youngest two life stages (birth to <1month and 1 to <3 months) have especially high 

drinking water ingestion rates. HRLs derived from the aggregated life stage of birth to <6 months 

would place some of the very young infants at high risk of exceeding the current RfD. For example, 

the HRL for the aggregated life stage at the mean ingestion rate is 4 ug/L. This would leave infants 

under three months of age at high risk of exceeding the RfD because they require an HRL of 3 or 

less to limit cumulative exposure below the RfD. 

The HRLs are lowest for children ages two and under, consistent with the published data showing 

that infants and children have high baseline perchlorate exposures from food and relatively high 

water ingestion rates; therefore, infants and young children can easily exceed the current RfD by 

drinking tap water contaminated with even very small concentrations of perchlorate (Murray et al 

2008, EWG 2008). For infants six months of age and under, the agency estimates HRLs from 1 to 5 

parts per billion, depending on the exact age and mean drinking water ingestion rate. 

Response: See response to comment code 5220. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection (MassDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0495 

EPA Comment ID: 29098 

EPA Comment Code: 5225 

 
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Comment: 3) Other sensitive populations should not be forgotten when EPA is addressing levels 

of health concern and potential numbers of people exposed to perchlorate in drinking water. Other 

sensitive subgroups not explicitly addressed include individuals with low iodine intake, untreated 

thyroid conditions, those suffering from cardiovascular and renal diseases (Miller et al. 2009; Iglesias 

and Diez 2009), individuals exposed to mixtures of other thyroid stressors, the elderly who are often 

prone to thyroid problems, and people with thyroid cancer. The results of Blount et al 2006 also 

indicate that women should be considered a sensitive group, certainly at the current RfD. 

Response: EPA has calculated HRLs for women ages 15-44 as part of the final regulatory 

determination. 

EPA agrees that these are sensitive groups and will consider them during the rulemaking process. 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 5230 Calculation of frequency of exposure above the 

HRL among pregnant women 

Individual Comments 

Commenter Name: Gregg Grunenfelder 

Commenter Organization: Washington State Department of Health; and Oregon Department of 

Human Services 

EPA Document ID: EPA-HQ-OW-2008-0692-1529 

EPA Comment ID: 20457 

EPA Comment Code: 5230 

 

Comment: Table 2 presents a subset of EPA developed estimates of the population served by water 

systems for which the highest reported perchlorate concentration was greater than various threshold 

concentrations ranging from 4 ug/L to 25 ug/L. If lower threshold values derived from California, 

New Jersey, or Massachusetts were applied, the estimated number of potential exposed population 

would greatly increase. No value was estimated for a threshold corresponding to Massachusetts 

MCL of 2 ug/L, but is likely to be doubled that projected for a threshold value of 4 ug/L with 

greater than 30 million people within the United States potentially served by Public Water Systems 

with at least one detection greater than the threshold. The population estimates for entry or sample 

points having at least one detection greater than the threshold would likely be over 10 million, half 

of whom are female and greater than 210,000 may be pregnant at anyone time. 

[Table 2. Occurrence and Population Estimates for Perchlorate Above Various thresholds - see PDF 

Docket ID EPA-HQ-OW-2008-0692-1529] 

Response: Please see response to comment code 5220. 

Commenter Name: Robert Howd 

Commenter Organization: California Environmental Protection Agency, Water Toxicology 

Section 

EPA Document ID: EPA-HQ-OW-2008-0692-1671 

EPA Comment ID: 20649 

EPA Comment Code: 5230 

 

Comment: IV (B)(4), p 60277. The calculation of frequency of exposure makes the argument that a 

small proportion of women is pregnant at any one time, and therefore the percentage of the 

population at risk is quite limited, and there is no meaningful opportunity for a health risk reduction. 

This calculation ignores the fact that every individual is born of a pregnant female, and therefore the 

entire population of exposed individuals can be at risk at a critical formative period. The logical flaw 

in the EPA argument was to count pregnant females as at risk, rather than their fetuses, which 

assumes the effect is transient (in the pregnant females) rather than potentially permanent (in their 

offspring). 

Response: Please see response to comment code 5220. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20916 

EPA Comment Code: 5230 

 

Comment: However, even with the many errors, flaws, and omissions in EPA’s assessment, EPA 

still estimates that up to 2 million people throughout the U.S. could potentially be consuming water 

with levels of perchlorate that exceed this HRL. Here is EPA’s exact statement: 

"EPA’s best estimate is that 0.9 million people (with an upper bound estimate of 2 million people) 

may be consuming water containing perchlorate at levels that could exceed the HRL for perchlorate 

and the Agency estimates that fewer than 30,000 of them are pregnant women at any given time" 

(EPA 2008). 

It is astounding that EPA does not think it is necessary to set a stringent drinking water standard for 

perchlorate in order to protect 30,000 pregnancies annually. In addition, the 2 million people at risk 

include infants and children, so the subpopulations within this number that would benefit from a 

stringent drinking water standard would far exceed 30,000. 

Response: Please see response to comment code 5220. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21101 

EPA Comment Code: 5230 

 

Comment: VIII. EPA Should Publish a More Accurate Estimate of the Population Exposed above 

the HRL in the Final Determination 

In the proposed determination, EPA estimates that 16,000 pregnant women may consume drinking 

water with concentrations above the HRL of 15 ppb. It was appropriate to estimate pregnant 

women, because although we all begin life as a fetus, the fetal exposure period is finite and an 

individual becomes less susceptible to the effects of possible reduced thyroid function as he ages. 

The actual number is likely to be much lower than the estimate in the proposed determination. 

Response: Please see response to comment code 5220. 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 5240 Consideration of other sensitive subpopulations 

(e.g., infants, children, and persons with iodine deficiency or thyroid disorders) 

when establishing the HRL 

Individual Comments 

Commenter Name: Melanie A. Marty, Ph.D. 

Commenter Organization: Children's Health Protection Advisory Committee 

EPA Document ID: EPA-HQ-OW-2008-0692-0962 

EPA Comment ID: 20419 

EPA Comment Code: 5240 

 

Comment: A number of states have recently established perchlorate drinking water standards or 

goals that are more appropriate than USEPA's HRL published in the Oct 10th FR notice. The New 

Jersey MCL is 5 ug/L, the California Public Health Goal is 6 ug/L and the Massachusetts MCL is 2 

ug/L. These drinking water values were intended to keep perchlorate exposures below the RfD for 

all groups including young children. Approximately 4% of public water supplies serving 17 million 

Americans would be in exci.edance of an HRL between 2 and 6 ug/L. This is 15 million more at risk 

individuals than currently estimated by the Agency. Thus, the proposed HRL of 15 ug/L has the 

potential to leave large numbers of infants inadequately protected against perchlorate. 

Response: EPA has determined that perchlorate meets the criteria for regulating a contaminant in 

Section 1412(b)(1)(A) of SDWA. When EPA proposes the NPDWR for perchlorate, the Agency 

will also propose a Maximum Contaminant Level Goal (MCLG) for perchlorate. See response to 

comment code 5220. 

Commenter Name: Carol Bigelow 

Commenter Organization: University of Massachusetts 

EPA Document ID: EPA-HQ-OW-2008-0692-1427 

EPA Comment ID: 20627 

EPA Comment Code: 5240 

 

Comment: Perchlorate interferes with thyroid function in both animals and humans. A 

consideration of known differences in thyroid physiology between adults and neonates/infants 

supports the conclusion that the neonate and infant are the most "at risk" population. 

Three important differences in thyroid physiology between adults and neonates/infants supports the 

conclusion that this population is the most vulnerable to perchlorate exposure (reviewed by 

(Ginsberg et al., 2007)): 

1) Serum half-life of the thyroid hormone T4 is substantially longer in the adult relative to the 

neonate (7-10 days (Chopra and Sabatino, 2000)) versus 3 days (Lewander et al., 1989; van den Hove 

et al., 1999). This means that for adults, serum thyroid hormone levels are stable in the face of the 

daily fluctuations in perchlorate exposure and iodine uptake that might arise from drinking water 

contaminated with perchlorate. In contrast, the shorter serum half-life of T4 in the neonate means 

that there will be a much more rapid response to the inhibition of iodine uptake by perchlorate. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 486 of 1099

2) The adult thyroid gland stores a considerable amount of hormone, possibly enough for several 

months of normal secretion (Greer et al., 2002). Consequently, adults can presumably function 

normally without new hormone synthesis for extended periods. In contrast, the neonatal thyroid 

gland contains essentially no extra hormone and the amount of thyroid hormone in the neonatal 

gland represents a single day’s worth of hormone (van den Hove et al., 1999). Therefore, the 

neonate must generate new hormone on a daily basis and perturbations in iodine uptake can have 

significant consequences. 

3) The adult thyroid system can compensate for low thyroid hormone levels and the consequences 

of low thyroid hormone are likely to be reversible. This is in contrast to the neonatal thyroid gland 

which does not readily compensate for low thyroid hormone (reviewed by (Ginsberg et al., 2007)), 

and the consequences of low thyroid hormone at this time are not reversible (reviewed by (Rovet, 

2002; Zoeller and Rovet, 2004). 

Thus, neonates and infants represent unique "at risk" populations in the matter of perchlorate 

exposure and its effects on public health. 

Response: See response to comment code 5220. 

Commenter Name: Carol Bigelow 

Commenter Organization: University of Massachusetts 

EPA Document ID: EPA-HQ-OW-2008-0692-1427 

EPA Comment ID: 20632 

EPA Comment Code: 5240 

 

Comment: Considering that the Blount study (Blount et al., 2006a) is the only study available to the 

EPA that had the ability to identify a relationship between life-time, low-dose perchlorate exposure 

and thyroid function, this study should supercede the Greer 2002 study for the derivation of the 

RfD. This study demonstrates that, in women with low urinary iodide, perchlorate exposure at the 

50th percentile is associated with a 1.06 ug/dL reduction in serum total T4. While this may be of 

uncertain clinical significance to adult women, it is clinically significant to an infant during highly 

sensitive periods of postnatal brain development. In addition, the EPA would then be in a stronger 

position because it would be regulating on hormone reduction, rather than iodide uptake inhibition. 

Moreover, it is now conclusively shown that perchlorate is transported by the sodium/iodide 

symporter (NIS) (Dohan et al., 2007) and is found at high levels in human milk (Kirk et al., 2007; 

Pearce et al., 2007). Thus, the US EPA should recalculate the RfD and HRL based on the CDC 

study as the point of departure. 

Response: See response to comment ID 29096 under comment code 5220. 

Commenter Name: Lenny Siegel 

Commenter Organization: Center for Public Environmental Oversight 

EPA Document ID: EPA-HQ-OW-2008-0692-2019 

EPA Comment ID: 20853 

EPA Comment Code: 5240 

 

Comment: November 24, 2008 
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US Environmental Protection Agency Office of Water Docket (Mail Code: 2822T) 1200 

Pennsylvania Avenue, NW Washington, DC 20460 

Ref: Docket EPA-HQ-OW-2008-068 

Dear Sirs/Mmes: 

In the October 10, 2008 Federal Register EPA made a preliminary determination that not enough 

people in the United States are exposed to significant levels of perchlorate in public drinking water 

systems to merit the issuance a national primary drinking water regulation. This is one of the most 

disappointing and convoluted EPA documents that I have ever reviewed. 

To reach that conclusion, it proposes to specify a health reference level of 15 parts per billion (ppb) 

based on its current reference dose of .7 micrograms per kilogram per day and a calculation of 

dietary sources of perchlorate other than drinking water. As other commenters have explained, EPA 

has failed to recognize that this health reference level exposes young children to levels of perchlorate 

above the reference dose. 

Response: See response to comment code 5220. 

Commenter Name: Apparent Mass Mailing #6 - Earth Justice 

EPA Document ID: EPA-HQ-OW-2008-0692-0972 

EPA Comment ID: 20885 

EPA Comment Code: 5240 

 

Comment: Many experts disagree with your assessment that drinking water with 15 parts per billion 

of perchlorate is safe and acceptable. Scientists from the California Environmental Protection 

Agency and the Massachusetts Department of Environmental Protection have set stricter standards 

to will ensure that the most vulnerable populations -- pregnant women, infants, and small children -- 

are protected from the adverse impacts of perchlorate. 

Response: See response to comment code 5220. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20905 

EPA Comment Code: 5240 

 

Comment: * EPA continues to consider pregnant women to be the population most at risk and 

ignores recent evidence that breast-fed infants and young children are the most highly exposed 

populations; 

Response: See response to comment code 5220. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment ID: 20913 

EPA Comment Code: 5240 

 

Comment: EPA focuses on risks to pregnant women while ignoring evidence of risks to breastfed 

infants and young children: There have been at least four published studies that highlight widespread 

perchlorate contamination of human breast milk. The most recent of these also postulated that 

perchlorate is preferentially excreted into breast milk when compared with iodine. Just as troubling, 

the average levels of perchlorate in breast milk in these studies would expose a significant number of 

breast fed infants to perchlorate levels above EPA RfD of 0.7 ug/kg/day. Breast fed infants do not 

get thyroid hormones through breast milk and must produce these hormones themselves; they are 

completely dependent on maternal iodine for thyroid hormone production and perchlorate exposure 

through breast milk could significantly inhibit this process. Adequate levels of thyroid hormones 

during infancy are integral to normal growth and brain development. 

Yet, despite growing evidence that breast fed infants are one of the most highly exposed populations 

and are uniquely vulnerable to perchlorate, EPA chooses to ignore this data. EPA does not even 

acknowledge this population as being at risk. In fact, EPA notes that "The subpopulation that is the 

most sensitive to perchlorate exposure is the fetus of the iodine-deficient pregnant women" while 

ignoring the evidence of risks to infants (EPA 2008). 

Similarly, young children are also highly exposed to perchlorate; FDA found that perchlorate 

contaminates 74% of 300 commonly consumed foods and beverages (Murray et al. 2008). It is well 

established that children eat and drink more, pound for pound, than adults. For this reason, 

perchlorate contamination of food is especially concerning for young children. FDA finds that 

among 2 year olds, perchlorate exposures from contaminated food and beverages alone fall between 

50 and 56% of EPA RfD of 0.7 ug/kg/day (Murray et al. 2008). EWG analysis of FDA data finds 

that additional exposures to perchlorate from contaminated drinking water could easily result in 

combined exposures that exceed the EPA RfD. The average two year old will exceed EPA’s RfD for 

perchlorate by drinking water that is contaminated with as little as 4 ppb of perchlorate (EWG 

2008). 

EPA does not explore risks to young children in any detail in their assessment, despite clear 

evidence from FDA research that perchlorate exposures from food are higher for young children 

than any other demographic group. As mentioned earlier, EPA focuses on the developing fetus of 

iodine-deficient pregnant women as the subpopulation that is at highest risk from perchlorate 

exposure while explicitly ignoring evidence that breast-fed infants and young children are also at risk. 

Response: EPA believes the NRC appropriately based the RfD on iodide uptake inhibition to the 

thyroid, for the reasons discussed in its report. See response to comment ID 28927 under comment 

code 2110. 

Commenter Name: Lucy Allen 

Commenter Organization: Pacific Institute 

EPA Document ID: EPA-HQ-OW-2008-0692-1770 

EPA Comment ID: 20926 

EPA Comment Code: 5240 

 
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Comment: Concern raised by the Children’s Health Advisory Committee regarding the unique 

levels of exposure and developmental impacts of perchlorate on breast-fed infants were not 

addressed, and the reference dose[FN1: 0.7 ug/kg/day, or 49 ug/day for an adult weighing 70kg] 

upon which the EPA based the preliminary decision may not adequately protect the health of breastfed infants. While the health risk posed by perchlorate to fetuses of pregnant women with 

hypothyroidism was considered in the preliminary regulatory determination, we are concerned that 

the health risk to breast-fed infants was not adequately addressed. Recommendations provided by 

the Children's Health Protection Advisory Committee (CHPAC) in its March 8, 2006 letter have not 

been appropriately adopted,[FN2: Children’s Health Protection Advisory Committee. (2006, March 

8). Letter to Stephen L. Johnson, EPA Administrator. Accessed Oct. 28, 2008 from 

http://www.ewg.org/files/chpac-epa_ltr.pdf.] which is especially disconcerting in light of the U.S. 

Government Accountability Office’s (GAO) recent finding that the EPA has routinely failed to 

respond to this committee’s findings.[FN3: U.S. Government Accountability Office (GAO). (2008). 

Environmental Health: EPA Efforts to Address Children's Health Issues Need Greater Focus, 

Direction, and Top-level Commitment. Accessed November 4, 2008 from 

http://www.gao.gov/new.items/d081155t.pdf.] Despite the EPA’s recognition that children may be 

more vulnerable to environmental hazards, the GAO found that the EPA has failed to proactively 

seek advice from the CHPAC and "largely disregarded key recommendations" from the 

committee.[FN4: GAO. (2008). Environmental Health: EPA Efforts to Address Children’s Health 

Issues Need Greater Focus, Direction, and Top Level Commitment. Retrieved Oct 27, 2008 from 

http://www.gao.gov/new.items/d081155t.pdf.] In the case of perchlorate, the committee 

emphasized the higher exposure of infants to perchlorate and greater susceptibility to serious 

negative effects associated with perchlorate exposure. Neither of these issues, however, was given 

adequate consideration in the Preliminary Determination. 

* Perchlorate is actively transported into human breast milk where it concentrates, resulting in 

exposure levels above the reference dose for infants feeding on this milk. In the Preliminary 

Determination for perchlorate, the EPA used a reference dose designed to "estimate the daily oral 

dose that is likely to have no appreciable risk of deleterious effects during a lifetime"[FN5: National 

Research Council (NRC). (2005). Health Implications of Perchlorate Ingestion. Washington, D.C.: 

The National Academies Press, 208.] of 0.7 ug/kg/day. However, the CHPAC calculated that 

infants would be exposed to perchlorate levels approximately 5-10 times higher than this reference 

dose with a maternal exposure of 24.5 ug/L of perchlorate in water, plus a dietary intake of 8.4 

ug/day. Because maternal exposure in this calculation is above the EPA’s reference dose, we 

recalculated infant exposure with a total maternal perchlorate exposure equal to the reference dose 

(0.7 ug/kg/day). The results showed that a breast-fed infant would be exposed to approximately 5-8 

times the reference dose.[FN6: Calculation of infant exposure to perchlorate: Nursing Infant Dose 

(ug/kg/d) = (ug/L in human milk/ug perchlorate ingestion-day) *[(24.5 ug perchlorate/L water)* (L 

water ingested/day)+ (baseline US dietary ingestion rate, ug/d)]*(L human milk ingested/day/infant 

body weight) Modified formula used by us to estimate infant exposure, with total maternal exposure 

equal to EPA’s reference dose of 0.7 ug/kg/day (assuming adult body weight of 70 kilograms, as 

was used by EPA in the Preliminary Regulatory Determination): Maternal exposure: ( 0.7 

ug/kg/day)*(70kg)= 49 ug/day Nursing Infant Dose (ug/kg/d) = (ug/L in human milk/ug 

perchlorate ingestion-day)*(49 ug/day)*(L human milk ingested/day/infant body weight) Aside 

from the maternal daily perchlorate exposure, we used the same parameter values as were used by 

the CHPAC. Please see the letter from CHPAC of March 8, 2006 for an explanation of these 

parameter values. Our infant exposure calculations: (0.458 day/L)*(49 ug/day)* (0.634 L 

milk/day/3.69 L) = 3.85 ug/kg/day (0.737 day/L )*(49 ug/day)* (0.634 L milk/day/3.69 L) = 6.20 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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ug/kg/day Calculation comparing infant exposure (calculated above) to the reference dose: 3.85 

ug/kg/day / (0.7 ug/kg/day)= 5.5 6.20 ug/kg/day / (0.7 ug/kg/day)= 8.86] 

* Infants are more susceptible to the serious neurological development effects of perchlorate, which 

can result in irreversible impacts. Due to their life stage, infants can suffer serious 

neurodevelopmental impacts because their central nervous system is still developing and is 

susceptible to small deficits of thyroid hormone level; they lack hormone reserves that adults have 

accumulated to buffer hormone deficits; and they may experience a slower clearance of perchlorate 

from their bodies. 

Response: Since the NRC also identified infants and developing children as additional life stages, 

EPA derived potential alternative HRLs for 14 life stages (age groups) using the RfD and life stagespecific exposure information in the August 9, 2009, notice (74 FR 41883; USEPA 2009b). These 

levels range from 1 μg/L to 47 μg/L and are the concentrations of perchlorate in drinking water 

that may result in total perchlorate exposures (from food and water) greater than the RfD for 

individuals at each life stage. These HRLs are calculated based on individuals who consume an 

average amount of perchlorate from food (except for pregnant women where EPA used a 90th

percentile dietary intake estimate), but who consume equal or more water on a per body weight basis 

than 90 percent of their cohorts. EPA is evaluating these potential alternative HRLs and considers 

them to be levels of public health concern for purposes of this determination. 

Commenter Name: Caroline Baier-Anderson, PhD 

Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20947 

EPA Comment Code: 5240 

 

Comment: Perchlorate and Iodine in infants 

The CDC study does not capture either perchlorate exposure or thyroid hormone response in 

infants, which is an important sensitive subpopulation. A recent study measuring iodine intake in 

breastfeeding infants found that only 1 in 13 infants was receiving adequate levels iodine, based on 

Institute of Medicine Guidelines (Dasgupta et al. 2008). In fact, six infants in the lower half of the 

group were receiving only between 12 and 29% of the suggested intake values for iodine (Dasgupta 

et al 2008). In this same study, the ingestion of perchlorate in human milk exceeded the reference 

dose for perchlorate in 9 out of 13 infants. The concentrations of perchlorate and iodine reported in 

this study were generally similar to earlier studies, including Kirk et al. 2005 and 2007 and Blount et 

al. 2007. 

Response: No response necessary to the information provided by the commenter. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20980 

EPA Comment Code: 5240 

 
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Comment: In addition to its preliminary determination not to regulate perchlorate in drinking 

water, EPA has proposed an HRL of 15 micrograms/L (ug/L, equal to parts per billion, ppb) of 

perchlorate in drinking water, assuming 62% of the daily perchlorate dose comes from water, and 

the rest comes from food.[FN4: 73 Fed. Reg. at 60275.][FN5: Calculation of the HRL: For all 

populations, including pregnant women, the RfD is 0.7 ug/kg/day. EPA reports that for pregnant 

women, exposure to perchlorate from food is 0.263 ug/kg/day at the 90th percentile, representing 

nearly 38% of the RfD, and thus leaving an RSC (relative source contribution) for water of 62% (FR 

at 60276). This is equavelent to 0.437 ug/kg/day from water, assuming an average body weight of 

70 kg, and a daily water consumption of 2 L. That is, 0.437 ug x 70 kg body wt. = 30.6 ug 

perchlorate in 2 L (the daily consumption amount). This is 15 ug/L, or 15 ppb, the HRL.] The HRL 

"will be the basis for the health advisory value in the health advisory document the Agency expects 

to issue at that time. Thereafter, it may be appropriate to use the health advisory value as a "to be 

considered" (TBC) value in developing potential cleanup levels for perchlorate at Superfund 

sites."[FN6: Id. at 60265.] The HRL is not protective of sensitive sub- populations and EPA's own 

scientists have produced strong evidence using PBPK modeling that this level of water 

contamination would mean bottle-fed infants would exceed the EPA reference dose or ‘safe’ level of 

0.7 ug/kg/day by five- fold, and young children would exceed the reference dose by 2.8-fold (based 

on average food contamination rates, average body weights, and 90th percentile water consumption 

rates for each age group). Furthermore, EPA's HRL determination did not include consideration of 

a subpopulation that is likely to be highly exposed to perchlorate and uniquely sensitive: the breastfeeding neonate. 

Response: See response to comment code 5210 for a discussion of the RSC and response to 

comment code 5220 for a discussion of HRLs. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20991 

EPA Comment Code: 5240 

 

Comment: B. EPA's analysis fails to consider the health risks perchlorate poses to key sensitive 

sub-populations. 

EPA has stated in its preliminary determination that the most sensitive subpopulations are women 

of reproductive age and the fetus. This determination improperly excludes consideration of other 

sensitive subpopulations including pre-term infants, neonates and breast-feeding infants. Recent 

studies demonstrate that infants born to low-iodide women are the most at-risk population, because 

of both high dietary exposures and because infancy is a highly sensitive developmental stage. 

Disruptions to normal hormone activity during this time is likely to result in permanent 

abnormalities. EPA has not adequately accounted for this sub-population in its analysis or its PBPK 

modelling. 

Infants are routinely being exposed to unsafe levels of perchlorate and a major route of exposure is 

through contaminated breast milk. A collaborative study from the CDC and Boston University 

examined breast milk samples from 49 Boston area women and found the median breast milk 

perchlorate level was 9.1 ppb (range 1.3 to 411 ppb).[FN25: EN Pearce, AM. Leung, BC Blount, HR 
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Bazrafshan, X He, S Pino, L Valentin-Blasini, and LE Braverman, 2007. Breast milk iodine and 

perchlorate concentrations in lactating Boston-area women. J Clin Endocrinol Metab. 92(5):1673-7.] 

To make matters worse, the Boston study found that 47 percent of the babies tested were not 

getting adequate levels of iodine from breast milk. Since the effects of perchlorate are compounded 

by insufficient iodide consumption, these babies are at even greater risk for thyroid hormone 

disruption. Notably, the Boston study also found that even moms who ingested extra iodine by 

using iodized salt or taking multivitamins containing iodine did not always have sufficient iodine in 

their breast milk. This finding underscores the need for the government to take effective actions to 

significantly reduce perchlorate contamination of food and drinking water. 

The Boston study also measured perchlorate concentrations in the mother's urine, finding a median 

level of 3.0 ppb. More important than the actual values, however, is the fact that these 

concentrations are remarkably similar to levels of perchlorate found in the much larger Centers for 

Disease Control and Prevention (CDC) study of perchlorate exposure that tested the urine of more 

than 2,800 individuals.[FN26: Blount BC, L Valentin-Blasini, JD Osterloh, JP Mauldin, and JL 

Pirkle. 2007. Perchlorate exposure of the US population, 2001-2002. J Expo Sci Environ Epidemiol. 

17(4):400-7.] In that study, the median urinary perchlorate concentration was 3.6 ppb. Since the 

perchlorate exposures in the two studies are so closely aligned, one can assume that the high levels 

found in the Boston women's breast milk are, unfortunately, likely to be typical of the general U.S. 

population. 

Response: See response to comment code 5220. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20993 

EPA Comment Code: 5240 

 

Comment: C. EPA ignores data showing that pre-birth and newborn infants are a highly vulnerable 

sub-population based on health impacts. 

EPA's preliminary regulatory determination focuses on the number of pregnant women who are 

affected by perchlorate contamination; but this analysis ignores the fact that prebirth and newborns 

are also a highly vulnerable subpopulation. 

An earlier analysis by scientists with the CDC of a nationally representative sample of 2,299 U.S. 

residents greater than 12 years of age has documented that exposure to perchlorate poses potential 

health risks to women of child-bearing age and especially to their babies (hereinafter referred to as 

"Blount (2006)").[FN29: Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell KL. 

Urinary perchlorate and thyroid hormone levels in adolescent and adult men and women living in 

the United States. Environ Health Perspect. 2006 Dec;114(12):1865-71.] These data were not 

available at the time of the NRC review, but have since been published. This study tested the 

association of chronic perchlorate exposure, as measured by urinary perchlorate excretion, with total 

serum thyroxine (T4) concentration, and thyroid stimulating hormone (TSH) concentration. 
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For women with low iodine intake (defined by the World Health Organization as urinary iodine < 

100 ug/L),[FN30: World Health Organization (WHO). 1994. Indicators for assessing iodine 

deficiency disorders and their control through salt iodization. WHO/NUT/94.7. Geneva: 

WHO/International Council for the Control of Iodine Deficiency Disorders.] very low levels of 

perchlorate exposure were associated with decreased serum T4 and increased serum TSH; the CDC 

estimates that 36% of U.S. women have iodine intakes in this range. For iodine-sufficient women 

(defined as urinary iodine >= 100 ug/L), perchlorate exposure was associated with increased TSH. 

Increased TSH is an indicator that the body is attempting to compensate for a decrease in thyroid 

hormone production, and is clinically considered to be a more sensitive marker of subtle thyroid 

alteration than depressed levels of serum T4. When predicting changes in serum TSH with 

increasing perchlorate exposures, women with low iodine intake and TSH levels on the high end of 

the normal range (> 3.11 IU/L) appeared to be the most sensitive group. In this group, any increase 

in urinary perchlorate predicted an increase in TSH that was consistently more than twice the 

predicted increase in TSH for women with low iodine levels and median TSH levels. For unknown 

reasons, perchlorate was not associated with T4 or TSH levels in men. The observed changes in 

serum T4 and TSH in women are consistent with our understanding of how thyroid hormones are 

regulated in the body, and with the mechanism of toxicity of perchlorate. 

Importantly, the extremely low levels of perchlorate were associated with thyroid hormone 

disruptions - and the magnitude of these disruptions. The CDC researchers found that if a low 

iodine woman started with perchlorate exposure corresponding to 0.19 ppb in urine (the minimum 

level found), and then ingested enough perchlorate through food and/or drinking water to raise her 

urinary perchlorate level to 2.9 ppb (the median level found), her T4 levels would drop by 

13%.[FN31: The drop in T4 predicted to be 1.06 ug/dL; the percentage decrease is calculated as 

compared to the average T4 level found in the CDC study (8.27 ug/dL).] Similarly, if her urinary 

perchlorate level increased to 5.2 ppb (the 75th percentile exposure), her T4 levels would drop by 

16%. The maximum level of perchlorate exposure found was 100 ppb, which translated into a 29% 

decline in T4. 

The unique physiology of pregnancy and interactions between the mother and fetus makes both 

especially susceptible to the harmful effects of perchlorate. Maternal T4 is the only source of thyroid 

hormone for the fetus in the first trimester. Recent studies have shown that the cognitive 

development of the fetus is impaired in mothers with even mild disruptions in thyroid hormone 

levels, prompting the medical community to recommend thyroid hormone replacement therapy for 

pregnant women who are found to have sub-clinical hypothyroidism (mildly elevated TSH but 

normal T4).[FN32: Cooper, D. 2004. Sub-clinical thyroid disease: consensus or conundrum. Clinical 

Endocrinology 60 (410-412); Haddow JE, Palomake GE, Allan, WC, Williams JR, Knight GJ, and 

Gagnon J, et al. Maternal thyroid deficiency during pregnancy and subsequent neuropsychological 

development of the child. New England Journal of Medicine 1999: 341: 549-555; Pop VJ, Kuijpens 

J., van Baar, AL, Verkert, G. et al. 1999. Low maternal free thyroxine concentrations during early 

pregnancy are associated with impaired psychomotor development in infancy. Clinical 

Endocrinology 50 (149); Surks M., Ortiz E., Daniels G., Sawin C., Col N., Cobin R., Franklyn J. 

Hershman J., Burman K., Denke M., Gorman C., Cooper R., Weissman N. 2004. Subclinical 

Thyroid Disease. Subclinical Thyroid Disease. Journal of the American Medical Association 2004: 

228-238.] 

An analysis by Environmental Working Group reported that if the CDC's results for low iodine 

women with high-normal TSH levels are extrapolated to the general population, one would expect 
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more than 2 million women in the U.S. to become subclincally hypothyroidic as a result of drinking 

water contaminated with just 5 ppb of perchlorate.[FN33: Environmental Working Group. 2006. 

Thyroid Threat: Under Proposed Rocket Fuel Standards, Many Women Would Need Treatment To 

Protect Baby. Available at: http://www.ewg.org/node/20968] If these women became pregnant, 

they would require medical treatment to restore their thyroid hormones to normal levels and protect 

their babies from IQ deficits and abnormal development. 

Response: See response to comment code 5220. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20995 

EPA Comment Code: 5240 

 

Comment: An MCL below 1 ppb is required to adequately protect vulnerable newborn babies and 

their recommended sole source of nutrition, breast milk 

In June 2006, the State of Massachusetts (MA DEP) and its scientific advisors (MA DEP/DPH 

Advisory Committee) "unanimously concluded that [the RfD] did not fully account for the 

uncertainties surrounding science’s understanding of perchlorate toxicity and exposures."[FN45: MA 

DEP, "Update To 'Perchlorate Toxicological Profile And Health Assessment'" March 2006, page 

xii.] Following recommendations from their scientific experts, MA DEP finalized a Perchlorate 

Maximum Contaminant Level for drinking water and a Perchlorate Cleanup Standard of 2 ppb 

based on a review and assessment of all data available at the time. Likely because the Blount (2006) 

data were not yet available, the MA DEP drinking water and cleanup standards failed to consider the 

special exposure patterns of infants born to low-iodide women, whom we now know are the most 

at- risk population based on both high exposure and vulnerability to permanent and severe 

neurological impacts. Therefore, an MCL must be below 1 ppb to be truly health protective. 

Response: See response to comment code 6120. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 21006 

EPA Comment Code: 5240 

 

Comment: Furthermore, a maximum contaminant level below 1 ppb would afford reasonable 

protections to the health of the susceptible populations of pregnant women and breast-fed infants. 

Response: See response to comment code 6120. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-2082 

EPA Comment ID: 21018 

EPA Comment Code: 5240 
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Comment: Having reviewed your letter in detail, I’ll now address the specific issues raised. 

1. You express concern with in utero and postnatal development, particularly neonates with greater 

exposure than adults and who lack stores of thyroid hormone. 

Specifically, your letter states that EPA’s HRL of 15 μg/L is a flawed benchmark and would allow 

daily exposures to infants that are 2-5 times higher than the Reference Dose (RfD) and that this 

lifestage must be adequately protected. 

Based upon the conservative and health-protective NAS-based RfD and even more conservative 

Health Reference Level (HRL) benchmark, this lifestage will receive significant protection. The HRL 

relies on the NAS-recommended RfD that has several levels of caution built into calculation of the 

dose. The NAS report recommended an RfD of 0.7 μg/kg-d based on a level that causes no 

inhibition of iodine update or a No Observed Effect Level (NOEL)--the dose at which no effects 

occur, adverse or otherwise (NAS, 2005). The NAS panel stated that using a NOEL as the point of 

departure is a more conservative and health-protective approach than EPA’s customary approach of 

using the adverse effect (i.e., using a dose at which there is no observable adverse effect level or the 

Lowest Observable Adverse Effect Level; (NAS, 2005). The NAS panel also took care to distinguish 

between a No Observable Adverse Effect Level (NOAEL) and a NOEL. The experts observed that 

there was confusion between the two and clarified that the NOAEL is based upon an adverse effect, 

whereas the NOEL is based upon a dose at which no effect occurs, adverse or otherwise. (NAS, 

2005). EPA adopted the RfD recommended by the NAS and confirmed that it was conservatively 

based on the NOEL, not the NOAEL. 

In using a NOEL, the NAS committee adopted a notably cautious, health-protective approach. In 

addition, the NOEL has an additional safety factor of 10 added this factor to ensure protection for 

the most sensitive individuals in a population, in this case, hypothyroid or iodine-deficient pregnant 

women and their developing fetuses. Importantly, the NAS panel did consider other sensitive 

populations in addition to pregnant women and their fetuses. They also considered the potential 

effect on infants, developing children, people who have compromised thyroid function, and people 

who are iodidedeficient. While it has been argued that the infant or child is the more sensitive 

individual in the population; experts from the NAS perchlorate panel, US EPA, CA OEHHA, and 

others agree that pregnant women and their fetuses are the most sensitive, thus these other sensitive 

groups would be protected if the most sensitive group is protected. 

Response: The comment is addressed to the Children’s Health Protection Advisory Committee, not 

to EPA, therefore, a response is not appropriate. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-2082 

EPA Comment ID: 21023 

EPA Comment Code: 5240 

 

Comment: 6. Your letter states EPA’s HRL is too high for infants and would allow daily exposures 

to infants that are 2-5 times higher than the RfD. 
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Perchlorate is not known or likely to occur in public water systems with high enough frequency nor 

does it occur at levels or public health concern. The NHANES studies and breast milk 

biomonitoring studies, notwithstanding their limitations, reveal that the US population is not 

exposed to levels of perchlorate that could cause an adverse effect, even when all exposure sources - 

in food and water - are considered. EPA’s UCMR monitoring found a mean concentration of less 

than 10 ppb in systems with perchlorate - more than 100 times lower than the NAS’ estimated effect 

level. Only a few systems have found any samples with concentrations greater than 100 ppb. Even 

the maximum level detected in the US is approximately 50 times lower than the dose at which the 

NAS panel estimated adverse effects could begin. 

Response: The comment is addressed to the Children’s Health Protection Advisory Committee, not 

to EPA, therefore, a response is not appropriate. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21099 

EPA Comment Code: 5240 

 

Comment: VI. Sensitive Subpopulations Could Be Exposed to Drinking Water with Greater than 

15 ppb Perchlorate without Adverse Health Effects 

As stated in these comments, in the Intertox summary, and in our comments to EPA's May 1st, 

2007 notice, EPA should use an HRL equal to the RfD to reflect the conservative approach of the 

RfD and the ample evidence that exposure at the RfD have no effect on individuals, including 

sensitive subpopulations. 

However, even if EPA uses its methodology in the final determination, EPA should use a larger Bin 

III subgroup to mitigate the potential limitations discussed previously. Using the sample group of 

females of childbearing age increases the sample size significantly. Switching the subpopulation of 

concern to women of childbearing age increases the sample size by five-fold, lowering the reliance 

on just a few observations. More importantly, it captures the subpopulation the NAS panel 

identified as the most sensitive - fetuses of women with low iodine consumption. The most critical 

period for the fetus in a woman with sustained iodine deficiency may even occur before she knows 

she is pregnant. As EPA notes, assigning one value for consumption, body weight, and other 

parameters to represent all of pregnancy is difficult. For these reasons, if EPA continues its 

approach, we recommend EPA use the HRL derived from the Bin III estimate of food 

consumption for all women of childbearing age. 

Response: EPA agrees that would increase the population of interest from 97 to 503 but took a 

conservative approach in looking at women who knew they were pregnant during the NHANES 

survey. We also performed a curve fitting and an analysis to eliminate outliers. The calculated water 

dose of 0.559 vs 0.502 for pregnant women would have resulted in an HRL of 19 to 20 vs 15 using 

the pregnant population. 

Commenter Name: Andria Ventura 

Commenter Organization: Clean Water Action et al. 

EPA Document ID: EPA-HQ-OW-2009-0297-0528 
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EPA Comment ID: 28513 

EPA Comment Code: 5240 

 

Comment: In responding to this threat, EPA must set a drinking water standard for perchlorate 

that protects the most vulnerable subpopulations, particularly pregnant women, fetuses, infants, and 

small children. By interfering with the thyroid's ability to take up iodide, perchlorate can suppress 

the development of thyroid hormones critical to growth, development, and metabolism. This puts 

fetuses and children at particular risk for learning and behavioral disabilities; impaired gait, vision, 

and hearing; and even mental retardation. Exposure calculations must therefore consider the 

ingestion rates for these populations, and the reference dose should consider the particular 

vulnerabilities of these age groups. EPA should also include in its calculations low birth weight 

babies and underweight infants, as these populations may be extremely vulnerable. 

Response: See response to comment code 5220. 

Commenter Name: Kathy Curtis 

Commenter Organization: Alliance of Nurses for Healthy Environments (ANHE) 

EPA Document ID: EPA-HQ-OW-2009-0297-0651 

EPA Comment ID: 28544 

EPA Comment Code: 5240 

 

Comment: In responding to this threat, EPA must set a drinking water standard for perchlorate 

that protects the most vulnerable subpopulations, particularly pregnant women, fetuses, infants, and 

small children. By interfering with the thyroid's ability to take up iodide, perchlorate can suppress 

the development of thyroid hormones critical to growth, development, and metabolism. This puts 

children at particular risk for learning and behavioral disabilities; impaired gait, vision, and hearing; 

and even mental retardation. Exposure calculations must therefore consider the ingestion rates for 

these populations, and the reference dose should consider the particular vulnerabilities of these age 

groups. EPA should also include in its calculations low birth weight babies, and underweight infants 

as these populations may be extremely vulnerable. 

Response: See response to comment code 5220. 

Commenter Name: Diane Henshel 

Commenter Organization: The School of Public and Environmental Affairs, Indiana University 

EPA Document ID: EPA-HQ-OW-2009-0297-0492 

EPA Comment ID: 28600 

EPA Comment Code: 5240 

 

Comment: We disagree with the currently recommended HRL of 15 ug/L in drinking water. We 

have done a landscape scale analysis of newborn Low Birth weight in California counties in which 

perchlorate was detected in drinking water in at least 2 samples. Total number of counties included 

in the analysis was 13. Interestingly, at least one of the counties which we considered to have 

relatively high levels of perchlorate in the drinking water was included as a reference county in 

another study using the same health data, but using different methods to determine effect. 

We used regression analysis correlating the incidence of very low birth weight (LBW), as determined 

by the California Department of health services, with the mean concentration of perchlorate in the 
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drinking water samples in which perchlorate was at or above the detection limit. We found a 

statistically significant positive correlation between the presence of perchlorate- contaminated 

drinking water and LBW percentage at the population level, even when taking a measure of poverty 

(%uninsured) into account. Notably, there seems to be no threshold for LBW effects (although the 

lowest mean concentration evaluated was 3 parts per billion [ppb] perchlorate) and the relationship 

saturated by 10 ppb perchlorate in drinking water. Note that the effect of perchlorate on low birth 

weight appears to saturate below the EPA recommended HRL, and had no detectable threshold for 

the data used. (The detection limit was between 2 - 4 ug/L) Not only is the recommended HRL 

above a level at which there appears to be a positive correlation with increased incidence of LBW in 

newborns, but it is well above the saturating dose. Thus using 15 ug/L as an inflection point to 

analyze the differences in effects for populations exposed to perchlorate in DW above and below 15 

ug/L would be biasing the results of the study towards artificially finding no effect of perchlorate on 

LBW (a false negative). 

Diane Henshel dhenshel@indiana.edu 

Attachment [See PDF Docket ID EPA-HQ-OW-2009-0297-0492; note this is copyrighted material] 

Response: See response to comment code 5220. 

Commenter Name: Nsedu O. Witherspoon 

Commenter Organization: Children's Environmental Health Network 

EPA Document ID: EPA-HQ-OW-2009-0297-0674 

EPA Comment ID: 28736 

EPA Comment Code: 5240 

 

Comment: September 18, 2009 

Water Docket Environmental Protection Agency Mailcode 2822T 1200 Pennsylvania Avenue, NW 

Washington, D.C. 20460 

Re: Docket ID No. EPA-HQ-OW-2009-0297 

Submitted via www.regulations.gov 

The Children's Environmental Health Network (the Network) appreciates the opportunity to 

comment on the importance of regulating perchlorate in drinking water. We wish to associate 

ourselves with the comments submitted by Clean Water Action, the Center for Public 

Environmental Oversight et al on this topic. 

The Network is a national organization whose mission is to promote a healthy environment and to 

protect the fetus and the child from environmental health hazards. The Network's Board and 

committee members include internationally- recognized experts in children’s environmental health 

science and policy who serve on key Federal advisory panels and scientific boards. We recognize that 

children, in our society, have unique moral standing. The Children's Environmental Health Network 

was created to promote the incorporation of basic pediatric facts such as these in policy and 

practice: 
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* Children;s bodies and behaviors differ from adults. In general, they are more vulnerable than 

adults to toxic chemicals. * Children are growing. Pound for pound, children eat more food, drink 

more water and breathe more air than adults. Thus, they are likely to be more exposed to substances 

in their environment than are adults. Children have higher metabolic rates than adults and are 

different from adults in how their bodies absorb, detoxify and excrete toxicants. * Children's 

systems, including their nervous, reproductive, digestive, respiratory and immune systems, are 

developing. This process of development creates periods of vulnerability when toxic exposures may 

result in irreversible damage when the same exposure to a mature system may result in little or no 

damage. * Children behave differently than adults, leading to a different pattern of exposures to the 

world around them. For example, they exhibit hand-to-mouth behavior, ingesting whatever 

substances may be on their hands, toys, household items, and floors. Children play and live in a 

different space than do adults. For example, very young children spend hours close to the ground 

where there may be more exposure to toxicants in dust, soil, and carpets as well as low-lying vapors 

such as radon, mercury vapor or pesticides. * Children have a longer life expectancy than adults; 

thus they have more time to develop diseases with long latency periods that may be triggered by 

early environmental exposures, such as cancer or Parkinson's disease. 

Clear, sound science underlies these principles. A solid consensus in the scientific community 

supports these concepts. 

The world in which today's children live has changed tremendously from that of previous 

generations. There has been a phenomenal increase in the substances to which children are exposed. 

According to the EPA, more than 83,000 industrial chemicals are currently produced or imported 

into the United States. Thousands of chemicals are ubiquitous in our environment worldwide. 

Traces of hundreds of chemicals are found in all humans and animals. Every day, children are 

exposed to a mix of chemicals, most of them untested for their effects on developing systems. Many 

of these chemicals are readily passed across the placenta to the fetus, to the infant via breast milk, or 

via toys and other children's products. Many of these chemicals are also ingested in food and water. 

Many also are absorbed by children through the lungs by respiration of contaminated air. 

Response: No response necessary to the information provided by the commenter. 

Commenter Name: Nsedu O. Witherspoon 

Commenter Organization: Children's Environmental Health Network 

EPA Document ID: EPA-HQ-OW-2009-0297-0674 

EPA Comment ID: 28738 

EPA Comment Code: 5240 

 

Comment: In responding to this threat, EPA must set a drinking water standard for perchlorate 

that protects the most vulnerable subpopulations, particularly pregnant women, fetuses, infants, and 

small children. By interfering with the thyroid's ability to take up iodide, perchlorate can suppress 

the development of thyroid hormones critical to growth, development, and metabolism. This puts 

fetuses and children at particular risk for learning and behavioral disabilities; impaired gait, vision, 

and hearing; and even mental retardation. Exposure calculations must therefore consider the 

ingestion rates for these populations, and the reference dose should consider the particular 

vulnerabilities of these age groups. EPA should also include in its calculations low birth weight 

babies, and underweight infants as these populations may be extremely vulnerable. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 500 of 1099

Response: See response to comment code 5220. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28815 

EPA Comment Code: 5240 

 

Comment: However, even if EPA proceeds with its determination not to regulate perchlorate and 

instead finalizes an HRL, that level must be adjusted to account for the actual data from the PBPK 

model showing that hundreds of thousands of infants would exceed the safe daily perchlorate intake 

levels at the proposed HRL. 

These comments are respectfully submitted for your consideration, 

Jennifer Sass, Ph.D. Mae Wu, JD 

Response: See response to comment code 5220. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection (MassDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0495 

EPA Comment ID: 28861 

EPA Comment Code: 5240 

 

Comment: Section III(B): Comments on Alternative Approaches for Calculating Health Reference 

Levels (HRLs) 

1) MassDEP recommends that EPA use the approach to setting HRLs as shown in Section III, 

Subsection B-3. 

2) We support EPA's reassessment of exposure assumptions for life stages, including fetuses of 

gestation week 40, infants and developing children. Application of EPA's Guidance on Selecting 

Age Groups for Monitoring and Assessing Childhood Exposures to Environmental Contaminants is 

appropriate along with application of EPA's Guidance for Risk Characterization to convey the 

variability in risk levels experienced by different individuals in the population. In doing so, EPA has 

appropriately taken into account specific and appropriate exposure values for many but not all 

potentially sensitive life stages. Because of the potential sensitivity of the early neonatal period from 

birth to several days thereafter, we believe that exposures to the bottle-fed 7- day old should also be 

considered. In EPA's Interim Drinking Water Health Advisory for Perchlorate, the 7-day old bottlefed infant was estimated to have the highest perchlorate exposure per body weight. 

Response: See response to comment code 5220. Since the NRC also identified infants and 

developing children as additional life stages, EPA derived potential alternative HRLs for 14 life 

stages (age groups) using the RfD and life stage-specific exposure information in the August 9, 2009, 

notice (74 FR 41883; USEPA 2009b). These levels range from 1 μg/L to 47 μg/L and are the 

concentrations of perchlorate in drinking water that may result in total perchlorate exposures (from 

food and water) greater than the RfD for individuals at each life stage. These HRLs are calculated 
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based on individuals who consume an average amount of perchlorate from food (except for 

pregnant women where EPA used a 90th percentile dietary intake estimate), but who consume equal 

or more water on a per body weight basis than 90 percent of their cohorts. EPA is evaluating these 

potential alternative HRLs and considers them to be levels of public health concern for purposes of 

this determination. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28876 

EPA Comment Code: 5240 

 

Comment: Vulnerable populations have been considered since the first risk assessment in 1998. All 

of EPA's interim guidance and the current RfD (which is the basis for the 2008 HRL) are based on 

the most sensitive subpopulation, the developing fetus. 

A small percent of those who commented on EPA's preliminary regulatory determination opined 

that the infant or child is the most sensitive population to perchlorate health effects; however, 

experts, including authoritative bodies such as the National Academy of Sciences (NAS) National 

Research Council (NRC) perchlorate committee as well as federal and state agencies such as the 

EPA, the Agency for Toxic Substances and Disease Registry (ATSDR), the California 

Environmental Protection Agency Office of Environmental Health Hazard Assessment (OEHHA), 

and others, conclude that the fetus is the most sensitive population to protect (all others being less 

sensitive than the fetus are therefore protected). Furthermore, questions about alternative life stages 

being more sensitive to perchlorate exposure have been addressed in the past; EPA began focusing 

on the most sensitive life stage as the foundation of health protection as early as 1998 in its first risk 

assessment (U.S. EPA, 1998a). 

Response: Since the NRC also identified infants and developing children as additional life stages, 

EPA derived potential alternative HRLs for 14 life stages (age groups) using the RfD and life stagespecific exposure information in the August 9, 2009, notice (74 FR 41883; USEPA 2009b). These 

levels range from 1 μg/L to 47 μg/L and are the concentrations of perchlorate in drinking water 

that may result in total perchlorate exposures (from food and water) greater than the RfD for 

individuals at each life stage. These HRLs are calculated based on individuals who consume an 

average amount of perchlorate from food (except for pregnant women where EPA used a 90th

percentile dietary intake estimate), but who consume equal or more water on a per body weight basis 

than 90 percent of their cohorts. EPA is evaluating these potential alternative HRLs and considers 

them to be levels of public health concern for purposes of this determination. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28887 

EPA Comment Code: 5240 

 

Comment: Some have opined that the infant is the most sensitive individual in the population, but 

no scientific basis for this has been presented. The weight of evidence shows that the fetal brain is 

more sensitive to hypothyroidism than the neonate or infant brain (Boelaert and Franklyn, 2005). 
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There is no scientific evidence presented in the Notice that demonstrates that other life stages are 

more sensitive with regard to the development of health protective toxicity guidelines values than 

the fetus. 

The NRC considered all possible sensitive populations in addition to pregnant women and their 

fetuses; this included infants, developing children, people who have compromised thyroid function, 

and people who are iodide-deficient, as sensitive to perchlorate exposure. Based on its assessment, 

the NRC committee states that "...fetuses and preterm newborns constitute the most sensitive 

populations although infants and developing children are also considered sensitive populations" 

(NRC, 2005). The purpose of defining an RfD based on "the most sensitive population" is that all 

other populations, including those that are more sensitive than average (but less sensitive than the 

most sensitive), would not be expected to have adverse effects, including at doses that exceed the 

RfD. To date-and with substantial scientific justification-the EPA, ATSDR, the states of California, 

Massachusetts, and New Jersey all regard fetuses to be the most sensitive population for health 

effects evaluations. 

The RfD is an estimate or a representation of the acceptable level of risk for a lifetime of exposure. 

It is not a threshold above which adverse effects occur. 

Reliable scientific studies published since NRC (2005) continue to demonstrate that no observable 

effect occurs at doses below the RfD. On a weight-of-evidence basis, the scientific literature 

demonstrates no significant health risk to the most sensitive individuals who consume water on a 

daily basis over a lifetime at environmentally relevant doses. Overall, these studies demonstrate that 

perchlorate is a ubiquitous chemical. It is naturally formed and is ubiquitous in the environment 

(Dasgupta et al., 2005), food (Murray et al., 2008), and the human body (Blount et al., 2006; Pearce 

et al., 2007b). 

The RfD is an estimate of the acceptable level of risk for a lifetime of exposure. It is not a threshold 

above which adverse effects occur. This is particularly true for the perchlorate risk assessment which 

is based on a NOEL, a more conservative POD than a NOAEL or LOAEL. EPA is correct in 

setting acceptable exposure levels with margins of safety. This allows, for example, an individual to 

consume a dose above the RfD on one day and ingest a lower dose on a subsequent day. When 

considering perchlorate, the issue relative to other chemicals is less of a concern: perchlorate is not 

metabolized, does not bioaccumualate, and the half-life is approximately 8 hours. Thus, in the rare 

instance of an exceedence of the RfD over the short term, perchlorate leaves the body quickly. 

Currently, EPA's use of a ten-fold intraspecies factor in the RfD effectively covers the potential for 

differences in sensitivity and exposure. 

The RfD is based on a NOEL for IUI. IUI is not adverse. It is not scientifically justified to use 

drinking water rates for specific life stages to lower the HRL when the current RfD already has an 

OF applied to account for the most sensitive individuals. EPA offers no justification for why other 

life stages might be currently at risk or why additional protection is needed. EPA remarks "The 

NRC (2005) identified 'the fetuses of pregnant women who might have hypothyroidism or iodide 

deficiency' as 'the most sensitive population,' but also identified infants and developing children as 

additional 'sensitive populations.'" The purpose of defining an RfD based on "the most sensitive 

population" is that all other populations, including those that are more sensitive than average, would 

not be expected to have adverse effects, including at doses that exceed the RfD. In addition, 
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reporting that the HRL could be lower in a group that is not the most sensitive without scientific 

support is not in compliance with the scientific method. 

Bereft of scientific evidence, the Notice fails to present justification to alter the HRL based on 

specific life stages, particularly when the current RfD already has an uncertainty factor applied to 

account for the most sensitive individuals. 

The purpose of defining an RfD based on "the most sensitive population" is that all other 

populations, even if they are more sensitive than average, would still be unlikely to suffer adverse 

effects, even at doses that exceed the RfD. 

Response: EPA disagrees, the life stages at which individuals are most sensitive and therefore at 

greatest risk of adverse effect (the fetus, infant, and developing child) are inherently less than a 

lifetime. See response to comment ID 28338 under comment code 5225. Since the NRC also 

identified infants and developing children as additional life stages, EPA derived potential alternative 

HRLs for 14 life stages (age groups) using the RfD and life stage-specific exposure information in 

the August 9, 2009, notice (74 FR 41883; USEPA 2009b). These levels range from 1 μg/L to 47 

μg/L and are the concentrations of perchlorate in drinking water that may result in total perchlorate 

exposures (from food and water) greater than the RfD for individuals at each life stage. These HRLs 

are calculated based on individuals who consume an average amount of perchlorate from food 

(except for pregnant women where EPA used a 90th percentile dietary intake estimate), but who 

consume equal or more water on a per body weight basis than 90 percent of their cohorts. EPA is 

evaluating these potential alternative HRLs and considers them to be levels of public health concern 

for purposes of this determination. See response to comment 5220. 

 
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EPA Comment Code: 5300 SDWA Criterion #3 – EPA’s determination that 

regulating perchlorate with a NPDWR would not represent a meaningful 

opportunity to reduce health risks for persons served by public water systems 

Response to Code 5300: Using the criteria mandated by the 1996 SDWA Amendments EPA has 

determined that regulation of perchlorate in drinking water systems presents a meaningful 

opportunity to reduce health risk for persons served by public water systems and has decided to 

begin development of a national primary drinking water regulation for perchlorate. See response to 

comment code 6120. 

Individual Comments 

Commenter Name: Apparent Mass Mailing #1 - Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0081 

EPA Comment ID: 19688 

EPA Comment Code: 5300 

 

Comment: Setting a standard for perchlorate will absolutely present ‘a meaningful opportunity for 

health risk reduction.’ I urge you to do so in accordance with the Safe Drinking Water Act and 

protect Americans’ health. 

Response: See response to comment code 5300. 

Commenter Name: Apparent Mass Mailing #1 - Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0081 

EPA Comment ID: 19688 

EPA Comment Code: 5300 

 

Comment: Setting a standard for perchlorate will absolutely present ‘a meaningful opportunity for 

health risk reduction.’ I urge you to do so in accordance with the Safe Drinking Water Act and 

protect Americans’ health. 

Response: See response to comment code 5300. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0117 

EPA Comment ID: 19698 

EPA Comment Code: 5300 

 

Comment: Setting a standard for perchlorate will absolutely present ‘a meaningful opportunity for 

health risk reduction.’ I urge you to do so in accordance with the Safe Drinking Water Act and 

protect Americans’ health. 

Response: See response to comment code 5300. 

Commenter Name: J Mason 

Commenter Organization: 
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EPA Document ID: EPA-HQ-OW-2008-0692-0145 

EPA Comment ID: 19727 

EPA Comment Code: 5300 

 

Comment: Setting a standard for perchlorate will absolutely present ‘a meaningful opportunity for 

health risk reduction.’ I urge you to do so in accordance with the Safe Drinking Water Act and 

protect Americans’ health. 

Response: See response to comment code 5300. 

Commenter Name: A. Lane 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0276 

EPA Comment ID: 19782 

EPA Comment Code: 5300 

 

Comment: Setting a standard for perchlorate will absolutely present ‘a meaningful opportunity for 

health risk reduction.’ I urge you to do so in accordance with the Safe Drinking Water Act and 

protect Americans’ health. 

Response: See response to comment code 5300. 

Commenter Name: S. G. Gompf 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0490 

EPA Comment ID: 19912 

EPA Comment Code: 5300 

 

Comment: By EPA's own data collection, perchlorate is present in drinking water in 35 states; by 

independent studies, the EPA has permitted up to 40 million Americans to be exposed to this 

harmful chemical. 

Setting a standard for perchlorate is absolutely â€ ̃a meaningful opportunity for health risk 

reduction.â€TM I urge the EPA to do so in accordance with the Safe Drinking Water Act and protect 

the health of America's mothers and children. 

Response: See response to comment code 5300. 

Commenter Name: Rebecca Fletcher 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0530 

EPA Comment ID: 19943 

EPA Comment Code: 5300 

 

Comment: We need to create standards for regulating the presence of this chemical in our water. 

Setting a standard for perchlorate will absolutely present â€ ̃a meaningful opportunity for health risk 

reduction.â€TM I urge you to do so in accordance with the Safe Drinking Water Act and protect 

Americansâ€TM health. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Thank you! 

Wishing you good health, Rebecca Fletcher 

Florence, MA 413-863-9038 

Response: See response to comment code 5300. 

Commenter Name: Margaret Baco 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0624 

EPA Comment ID: 19997 

EPA Comment Code: 5300 

 

Comment: Setting a standard for perchlorate will absolutely present â€ ̃a meaningful opportunity 

for health risk reduction.â€TM I urge you to do so in accordance with the Safe Drinking Water Act 

and protect Americansâ€TM health. The absolute lowest level should be established immediately, 

with the commitment to essentially eliminate further contamination. Clean water is our greatest 

national resource. 

Response: See response to comment code 5300. 

Commenter Name: Apparent Mass Mailing #4 - Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-0687 

EPA Comment ID: 20017 

EPA Comment Code: 5300 

 

Comment: All Americans deserve healthy and clean drinking water. The EPA should not finalize 

this decision until the scientific review is complete and should make decisions that are consistent 

with the agency's own scientists. Contrary to your claims, protecting the health of young children is 

indeed a "meaningful opportunity for health risk reduction." 

Response: See response to comment code 5300. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0776 

EPA Comment ID: 20186 

EPA Comment Code: 5300 

 

Comment: * a national primary drinking water regulation would provide a meaningful opportunity 

to protect public health. 

Response: See response to comment code 5300. 

Commenter Name: Anonymous 

Commenter Organization: 
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EPA Document ID: EPA-HQ-OW-2008-0692-0671 

EPA Comment ID: 20245 

EPA Comment Code: 5300 

 

Comment: Perchlorate is found in drinking water in 35 states, and according to the EPAâ€TMs own 

data, 16 million Americans are at risk of being exposed to this dangerous chemical. Setting a 

standard for perchlorate will absolutely present â€ ̃a meaningful opportunity for health risk 

reduction.â€TM 

Response: See response to comment code 5300. 

Commenter Name: Ed Thomas 

Commenter Organization: National Rural Water Association (NRWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0163 

EPA Comment ID: 20272 

EPA Comment Code: 5300 

 

Comment: Second, Rubin, etal (see reference 2 electronic attachment - "Rubin trade off health risk 

final.pdf") [see PDF of docket ID EPA-HQ- OW-2007-0068-0163] have documented quantitative 

evidence that when regulatory costs increase in the order of $25 per month, significant numbers of 

customers are forced into spending choices that have health outcomes that may outweigh the 

projected benefits of the regulation. NRWA strongly feels that when evaluating whether a regulation 

will result in a meaningful health benefit, EPA must take these effects into consideration. This is 

essentially an affordability issue and NRWA recommends that EPA include appropriate affordability 

criteria in its CCL evaluation and its future determinations when regulating or not regulating 

perchlorate. 

Response: EPA has determined that the following three SDWA criteria for regulatory 

determination have been met for perchlorate: (1) It has an adverse effect on the health of persons; 

(2) It is known to occur in public water systems with a frequency and at levels of public health 

concern; and (3) In the sole judgment of the Administrator, regulation of perchlorate presents a 

meaningful opportunity for health risk reduction for persons served by public water systems. . This 

action notifies interested parties of EPA’s determination to regulate perchlorate, and thus imposes 

no requirements on public water systems. This action also initiates the process to develop a national 

primary drinking water regulation (NPDWR) for perchlorate. EPA will now begin developing a 

proposed NPDWR and Maximum Contaminant Level Goal (MCLG). EPA plans to publish the 

proposed NPDWR for public comment along with health risk reduction benefits, and cost analyses, 

feasibility analyses and other analyses required for regulatory development under the SDWA. In 

proposing an NPDWR the Administrator will also describe variance technology for perchlorate that 

the Administrator finds are available and affordable for public water systems of varying size, 

considering the quality of the source water to be treated. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group (PSG) 

EPA Document ID: EPA-HQ-OW-2007-0068-0168 

EPA Comment ID: 20282 

EPA Comment Code: 5300 

 
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Comment: EVALUATION OF POTENTIAL HEALTH EFFECTS ALONG WITH 

OCCURRENCE AND EXPOSURE RESULTS REVEALS THAT REGULATION OF 

PERCHLORATE WOULD NOT PRESENT A MEANINGFUL OPPORTUNITY FOR RISK 

REDUCTION 

EPA establishes the HRL based on the RfD and the RSC and then compares the occurrence data to 

the health benchmark. Assuming an RSC of one (which yields an HRL of 24.5 ppb drinking water 

equivalent), the population exposed to perchlorate in drinking water above EPA’s evaluative criteria 

- 1⁄2 and 1 times the health benchmark - are small fractions of the total population served by public 

drinking water systems. The populations exposed to perchlorate above these benchmarks is lower 

than the populations for other chemicals for which EPA has determined a drinking water standard 

would not reduce risk in a meaningful manner. 

A comparison of occurrence data for perchlorate and relevant compounds from EPA’s CCL 1 

regulatory determinations and CCL2 proposed determinations reveals that perchlorate ranks as a 

lower opportunity for risk reduction than sodium, manganese, sulfate, and boron, all four of which 

EPA has made or proposed determinations not to regulate. 

Further explanation of our evaluation of the third statutory criteria for meaningful opportunity for 

risk reduction is contained in Attachment 4 [See PDF of docket ID EPA-HQ-OW-2007-0068-

0168]. 

Response: See response to comment ID 21028 under comment code 5200. 

Commenter Name: Melanie A. Marty, Ph.D. 

Commenter Organization: Children's Health Protection Advisory Committee 

EPA Document ID: EPA-HQ-OW-2008-0692-0962 

EPA Comment ID: 20423 

EPA Comment Code: 5300 

 

Comment: The third condition of the SDWA, that the Agency has a meaningful opportunity for 

health risk reduction, is also met for perchlorate. The setting of an MCL will trigger requirements for 

testing to determine whether there are exceedances, and fortunately, sensitive test methods and 

effective treatment systems are readily available. Therefore, the Administrator has the opportunity to 

intervene to protect the health of millions of pregnant women and their fetuses, and lactating 

women and infants across the country who would otherwise be exposed to unsafe levels of 

perchlorate. 

Response: See response to comment code 5300. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection 

EPA Document ID: EPA-HQ-OW-2008-0692-1422 

EPA Comment ID: 20434 

EPA Comment Code: 5300 

 

Comment: 9. MassDEP Believes That a National Perchlorate Drinking Water Standard 

Provides a Significant Risk Reduction Opportunity. Table 2 of the Federal Register publication 
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provides information on the occurrence and population estimates for perchlorate above various 

thresholds. The table shows that up to 2.0 million people would be provided drinking water above 

15 ppb, a value that, based on EPA’s own estimates, is not protective of the breast or bottle fed 

infant, yet which is EPA’s proposed HRL. EPA does not explain in the Federal Register how it 

reached its conclusion that protecting up to 2.0 million people is not a meaningful opportunity for 

risk reduction for persons, in particular infants, served by public water systems. 

Response: EPA has determined that perchlorate meets the criteria for regulating a 

contaminant in Section 1412(b)(1)(A) of SDWA. As previously discussed in the Federal Register 

Notice, perchlorate may have an adverse effect on the health of persons and perchlorate is known to 

occur or there is a substantial likelihood that perchlorate will occur in public water systems with a 

frequency and at levels of public health concern. Moreover, in light of the discussion in this notice 

and the information available at this time, the Administrator finds that regulation of perchlorate in 

drinking water systems presents a meaningful opportunity for health risk reduction for persons 

served by public water systems. Therefore, EPA will initiate the process of proposing a NPDWR for 

perchlorate. See response to comment code 6120 and 5220. 

See response to comment code 5220. 

Commenter Name: J. Green 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0148 

EPA Comment ID: 20462 

EPA Comment Code: 5300 

 

Comment: Setting a standard for perchlorate will absolutely present ‘a meaningful opportunity for 

health risk reduction.’ I urge you to do so in accordance with the Safe Drinking Water Act and 

protect Americans’ health. 

Response: See response to comment code 5300. 

Commenter Name: Raimonde 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1513 

EPA Comment ID: 20502 

EPA Comment Code: 5300 

 

Comment: With respect to EPA-HQ-OW-2008-0068: 

It is recognized that this issue has been a difficult one and much work on behalf of EPA with it's 

extensive resources and interest groups, the dominant ones also possessing significant resources. 

However, EPA's proposal to avoid regulation fails to meet the Agency's overarching mandate to 

protect human health and the environment. We know of specific cases where in fact perchlorate 

exposure has affected public health and in those cases, there is little choice but for the public to 

consume a basic resource made available by their communities or their other limited means of water 

supply. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Although considering the argument regarding significance of the percentage of water supplies 

affected accounting for a small percentage, EPA has inproperly weighted its importance. What it has 

thus done, is use a predjudiced method to arrive at a conclusion that by regulating perchlorate, it 

would have no material effect on improving human health. This is clearly incorrect as the data 

reviewed by the wider scientific community has concluded that there are negative health effects 

resulting from exposure, some of them quite serious. We further know through no small body of 

evidence that regulating contaminants has demonstrated, without question, the improvement on 

public health. By arbitrarily setting the criteria at some percentage affected is contrary to sound 

public health protection and contrary to the public's expectation for EPA. 

For EPA to conclude based on the guidance criteria interpreted narrowly to mean that some 

percentage of affected are not significant is plainly contrary to the principles of the mandate to 

protect human health and the environment. 

I encourage the Agency to reconsider this matter and set a national standard. 

Response: See response to comment code 5300. 

Commenter Name: Thomas L. Schoaf 

Commenter Organization: Cities of Litchfield Park and Goodyear, AZ 

EPA Document ID: EPA-HQ-OW-2008-0692-1552 

EPA Comment ID: 20520 

EPA Comment Code: 5300 

 

Comment: Given that the first two SDWA criteria have been met, and that there are available 

technologies to treat perchlorate, we believe that the third and final criterion has also been met and 

that a national standard set by the EPA presents a meaningful and appropriate risk reduction 

opportunity. 

Further, a national standard is necessary to avoid a patchwork of potentially conflicting regulations 

amongst the various states . This is even more critical given that many states share water resources 

(such as the Colorado River water shared by Arizona and six other western states). 

Therefore, we, the undersigned, request that the EPA reconsider its determination and establish a 

national maximum contaminant level for perchlorate 

Respectfully, 

Thomas L. Schoaf, Mayor City of Litchfield Park 

James Cavanaugh, Mayor City of Goodyear 

cc: Senator John McCain Senator Jon Kyl Congressman Trent Franks Senator Robert Blendu 

Representative John Nelson Representative Jerry Weiers Councilmembers, City of Goodyear 

Councilmembers, City of Litchfield Park 

Water Docket, Docket ID No. EPA-HQ-OW-2008-0068 Environmental Protection Agency 

Mailcode : 2822T, 1200 Pennsylvania Ave., NW, Washington, DC 20460 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Mary Aycock U.S. Environmental Protection Agency Region IX 75 Hawthorne Street SFD-8-2 San 

Francisco, CA 94105-3901 

Cathy O'Connell Arizona Department of Environmental Quality 1110 W. Washington Street 

Phoenix, AZ 85007 

Response: See response to comment code 5300. 

Commenter Name: Jimmy Spearow 

Commenter Organization: Sacramento Chapter, Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-1672 

EPA Comment ID: 20590 

EPA Comment Code: 5300 

 

Comment: The data show that not regulating this harmful chemical in our drinking water is 

unacceptable. We disagree with the EPA statment that a national standard for perchlorate "would 

not present 'a meaningful opportunity for health risk reduction.'" Setting a standard for perchlorate 

will absolutely present 'a meaningful opportunity for health risk reduction.' 

Response: See response to comment code 5300. 

Commenter Name: Ed Thomas 

Commenter Organization: National Rural Water Association 

EPA Document ID: EPA-HQ-OW-2008-0692-1669 

EPA Comment ID: 20620 

EPA Comment Code: 5300 

 

Comment: Rubin, etal (see reference 1 electronic attachment - "Rubin trade off health risk 

final.pdf") [See PDF Docket ID EPA-HQ-OW-2008-0692-1669] have documented quantitative 

evidence that when regulatory costs increase in the order of $25 per month, significant numbers of 

customers are forced into spending choices that have health outcomes that may outweigh the 

projected benefits of the regulation. NRWA strongly feels that when evaluating whether a regulation 

will result in a meaningful health benefit, EPA must take these effects into consideration. This is 

essentially an affordability issue and NRWA recommends that EPA include appropriate affordability 

criteria in its final determination to not regulate perchlorate. 

Response: See response to comment code 5300, comment ID 20272. 

Commenter Name: Robert Howd 

Commenter Organization: California Environmental Protection Agency, Water Toxicology 

Section 

EPA Document ID: EPA-HQ-OW-2008-0692-1671 

EPA Comment ID: 20651 

EPA Comment Code: 5300 

 

Comment: IV (C), p 60280. A meaningful opportunity for health risk reduction. When drinking 

water consumption estimates that are protective of the exposed population are included in the 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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population exposure estimates, the number of people exposed to estimated excessive levels of 

perchlorate is markedly increased. When it is considered that the population at risk is not pregnant 

women, but their fetuses - and we all are fetuses once in our life - the population at risk balloons. 

Therefore it seems to us that the opportunity for a meaningful health risk reduction has been greatly 

understated. 

Response: See response to comment code 5300. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1748 

EPA Comment ID: 20655 

EPA Comment Code: 5300 

 

Comment: Fourth, since the scientific literature on perchlorate is extensive, EPA can rely on 

multiple approaches to determine that there would not be a meaningful opportunity for risk 

reduction through a national drinking water standard. As the PSG has stated in its public comments 

to EPA’s May 1, 2007 notice (see attached)[No attachement provided], EPA reached its conclusions 

through several approaches, all with ample scientific justification. The literature on human health 

effects from perchlorate consists mainly of clinical, occupational, or ecological studies. There are 

also some well designed animal studies that have contributed to the health effects database. As EPA 

has stated repeatedly, PBPK modeling allows the agency to give policy officials more scientific 

support for interspecies and intraspecies uncertainty factors. Following EPA’s first draft risk 

assessment for perchlorate in 1998, Dr. Curtis Klaassen, the Chair of the external peer review panel 

stated, "...a predictive risk assessment for perchlorate is possible and should be pursued in the next 

iteration of this assessment."[FN7: Curtis Klaassen, US EPA Perchlorate Peer Review Workshop, 

1999.] EPA’s consideration of its findings in its preliminary determination is exactly the use of 

compelling scientific information to support its policy decisions your November 5th letter [See PDF 

Docket ID EPA-HQ-OW-2008-0692-1749] endorses. 

Response: No response necessary to the information provided by the commenter. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1748 

EPA Comment ID: 20657 

EPA Comment Code: 5300 

 

Comment: While determining a "meaningful opportunity for risk reduction" is appropriately a 

policy decision it must be based on the best available scientific data. The best available data on 

perchlorate exposure suggest that very few individuals will be exposed to a dose of perchlorate 

greater than the RfD by drinking water with a perchlorate concentration above the HRL. Further, 

since the HRL is based on the NAS-recommended reference dose which is set at the no observed 

effect level (NOEL), which the NAS panel noted is a more conservative and health protective 

approach than using EPA’s traditional approach of relying on the no observed adverse effect level 

(NOAEL)[FN9: NAS at 169, (pdf version).], along with an additional safety factor applied to it, the 

quantifiable incremental risk would appear to be very small. 
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Response: See response to comment code 5200. Regarding the comment about exposures above 

the RfD, the data underlying the definition of iodide uptake inhibition as a precursor effect and 

its relationship to the continuum of adverse thyroid outcomes reflects an understanding of effects 

in adults. The relationship of the precursor event to the adverse outcome in children has not been 

studied. EPA notes that the data underlying the definition of iodide uptake inhibition as a 

precursor effect and the relationship of iodide uptake inhibition to the continuum of adverse 

outcomes reflects an understanding of effects in adults; it may not reflect the relationship of the 

precursor event to adverse outcomes in neonates and infants, who may not have iodide stores 

sufficient to offset the effects of reduced iodide uptake. The less resilient neonatal and infant 

system makes the exposure gap between a precursor event (iodide uptake inhibition due to 

perchlorate) and reduced T3/T4 levels likely to be narrower than for adults, and in fact, the 

distinction between the two may be blurred for the very young (Greer et al., 2002; Savin et al., 

2003; van den Hove et al., 1999). The NRC noted that, “[T]he minimal prolonged decrease in 

thyroid hormone production that would be associated with adverse health effects is not known; 

any decrease is potentially more likely to have adverse effects in sensitive populations (people 

with thyroid disorders, pregnant women, fetuses, and infants) but data are not available to 

determine the magnitude of the decrease needed to cause adverse effects in those populations.” 

Commenter Name: Lyndsey Crum 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1732 

EPA Comment ID: 20678 

EPA Comment Code: 5300 

 

Comment: November 10, 2008 

Eric Burneson Office of Ground Water and Drinking Water Standards and Risk Management 

Division Environmental Protection Agency 

RE: [EPA-HQ-OW-2008-0068; FRL-8727-6] Drinking Water: Preliminary Regulation 

Determination on Perchlorate 

The agency should adopt its determination not to enact a NPDWR for perchlorate on the basis of 

the authority to promulgate NPDWR under the Safe Drinking Water Act. 

The agency’s notice indicates that SDWA requires EPA to promulgate an NPDWR for a 

contaminate if three conditioned are identified: (a) The contaminate may have an adverse effect on 

the health of persons; (b) the contaminate is known to occur or there is a substantial likelihood that 

the containment will occur in public water systems with frequency and at levels of public health 

concern; and (c) in the sole judgment of the Administrator, regulation of such contaminate presents 

a meaningful opportunity for health risk reduction for persons served by public health water 

systems. 

The research presented and previous comments do not clearly establish condition two, and by 

construction, condition three. Therefore EPA is not required to regulate perchlorate in public water 

systems. 
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Response: See response to comment code 5300. 

Commenter Name: Heather Hesse-Stromberg 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1763 

EPA Comment ID: 20697 

EPA Comment Code: 5300 

 

Comment: Perchlorate contamination is a nationwide problem and has health impacts at lower 

levels than previously thought. A national primary drinking water regulation would provide a 

meaningful opportunity to protect public health. 

Response: See response to comment code 5300. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1983 

EPA Comment ID: 20820 

EPA Comment Code: 5300 

 

Comment: The EPA is not accurate in determining that NPDWR for perchlorate would "not 

present a meaningful opportunity for health risk reduction for persons served by public water 

systems." 

Response: See response to comment code 5300. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20897 

EPA Comment Code: 5300 

 

Comment: November 11, 2008 

U.S. Environmental Protection Agency Water Docket EPA Docket Center 1200 Pennsylvania 

Avenue, NW Washington, DC 20460 

Letter to EPA re: Preliminary Regulatory Determination on Perchlorate (Docket ID No. EPA-HQOW-2008-0692) 

Dear Administrator Johnson: 

Environmental Working Group (EWG) strongly disagrees with EPA’s recent finding that setting a 

national drinking water standard for perchlorate would not present "a meaningful opportunity for 

health risk reduction for persons served by public water systems" (EPA 2008). The science provides 

overwhelming evidence that the tens of millions of people drinking perchlorate in tap water face real 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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health risks that only EPA can protect them from. But the agency has chosen not to act and by 

failing to act, EPA has sacrificed its scientific integrity. 

Response: See response to comment code 5300. 

Commenter Name: Ron Curry 

Commenter Organization: New Mexico Environment Department 

EPA Document ID: EPA-HQ-OW-2008-0692-1796 

EPA Comment ID: 20938 

EPA Comment Code: 5300 

 

Comment: As to the third criterion, EPA concludes that a national primary drinking water 

regulation for perchlorate would not present a meaningful opportunity to reduce health risks for 

persons served by public water systems.[FN25: 73 Fed. Reg. at 60280.] EPA bases this conclusion 

on the flawed analysis, described above, in which the agency determined that perchlorate occurs 

only infrequently at levels of public health concern. EPA reiterated that of the 900,000 to two 

million people who may be ingesting public drinking water at levels above the HRL of 15 ug/L, 

"fewer than 30,000 of them are pregnant women at any given time."[FN26: Id.] EPA's conclusion 

fails to account for the reduced health risks to pregnant women in the future, and to their fetuses; to 

infants; and to persons with thyroid disorders. 

Response: EPA believes that regulating perchlorate in drinking water presents a meaningful 

opportunity for health risk reduction and has decided to regulate perchlorate in drinking water. See 

response to comment code 6120. 

EPA has made this determination based on a consideration of the best available peer reviewed 

science and data collected in accordance with accepted methods related to perchlorate occurrence in 

drinking water, the presence of perchlorate in foods, and the potential health effects of exposure to 

perchlorate. 

EPA has determined that perchlorate meets the criteria for regulating a contaminant in Section 

1412(b)(1)(A) of SDWA. As previously discussed in the Federal Register Notice, perchlorate may 

have an adverse effect on the health of persons and perchlorate is known to occur or there is a 

substantial likelihood that perchlorate will occur in public water systems with a frequency and at 

levels of public health concern. EPA believes that the UCMR 1 is the best available data on the 

frequency and level of perchlorate occurrence in public water systems nationally. UCMR 1 indicated 

that 5.1 to 16.6 million people are served by PWSs, for which we have data, that have detected 

perchlorate above the minimum reporting level. In light of the discussion in this notice and the 

information available at this time, the Administrator finds that regulation of perchlorate in drinking 

water systems presents a meaningful opportunity for health risk reduction for persons served by 

public water systems. Therefore, EPA will initiate the process of proposing a NPDWR for 

perchlorate. See response to comment code 6120 and 5220. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20981 
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EPA Comment Code: 5300 

 

Comment: The U.S. population is about 300 million people with about 6.8%, or 20 million, under 5 

years old. On average, therefore, there are about 4 million kids in each year of life (from zero to 

five). With 4 million kids under 1 year old, including infants, there are 400,000 in the 90th percentile 

of water consumers, meaning that at the proposed HRL, these 400,000 would have a perchlorate 

intake, each day for their whole first year of life, that exceeds the reference dose. EPA's proposed 

model shows that there are 400,000 children under the age of 1 who would exceed the daily 

reference dose and this is likely underestimate of the highly exposed. Thus, the evidentiary record 

does not support EPA's proposed determination. Rather, the evidentiary record makes clear that 

regulating these exposures does represent "a meaningful opportunity for health risk reduction for 

persons served by public water systems." 

Response: See response to comment codes 5200 and 5300. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 21000 

EPA Comment Code: 5300 

 

Comment: The U.S. population is about 300 million people.[FN55: U.S. Census Bureau quick facts. 

2006. http://quickfacts.census.gov/qfd/states/00000.html] Of the total, about 6.8%, or 20 million, 

are under 5 years old, an average of about 4 million kids of each year of life. This is a reasonable 

estimate supported by the fact that there were about 4,329,000 live births in the U.S. in 2007.[FN56: 

National Vital Statistics Reports, Vol 57, No 5. 

http://www.cdc.gov/nchs/data/nvsr/nvsr57/nvsr57_05.htm] If there are 4 million children less 

than 1 year old, including infants, then 400,000 of them would be in the 90th percentile of water 

consumers. This means that at the proposed HRL, 400,000 children and infants will exceed the 

reference dose for perchlorate every day for their entire first year of life. 

As part of its basis for the preliminary determination not to regulate perchlorate because it does not 

feel there is a meaningful opportunity to reduce health risks, EPA acknowledged that perchlorate 

could have an adverse effect on human health.[FN57: 73 Fed. Ref. at 60275.] 

 Furthermore, EPA's own staff experts have provided data to show that at the HRL, 400,000 infants 

and children would consume perchlorate on a daily basis that exceeded the reference dose. Rather, 

EPA states that 30,000 pregnant women would be exposed to these levels of perchlorate, and that 

number does not provide a meaningful opportunity to reduce health risks. While we take issue with 

EPA's determination that reducing the exposure of 30,000 pregnant women to perchlorate is not 

meaningful, EPA must explain why reducing the exposure of 400,000 children and infants to 

perchlorate is not a meaningful opportunity to reduce health risks. 

Response: See response to comment codes 5200 and 5300. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 
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EPA Comment ID: 21005 

EPA Comment Code: 5300 

 

Comment: Second, even without those peer review comments, existing data on perchlorate 

exposure and effects, especially on vulnerable subpopulations, demonstrates that setting a national 

primary drinking water standard for perchlorate would provide a meaningful opportunity for health 

risk reduction. EPA is therefore required to set such a standard under the Safe Drinking Water Act. 

Response: See response to comment code 5300. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-2082 

EPA Comment ID: 21029 

EPA Comment Code: 5300 

 

Comment: 12. Finally, your letter argues that the "meaningful opportunity for risk reduction" 

criterion is met because an MCL will trigger testing for exceedances. 

While determining a meaningful opportunity for risk reduction is appropriately a policy decision it 

must be based on the best available scientific data. The best available data on perchlorate exposure 

suggest that very few individuals will be exposed to a dose of perchlorate continuously for years 

greater than the RfD by drinking water with a perchlorate concentration above the HRL. Further, 

since the HRL is based on the NAS-recommended RfD which is set at the NOEL, which the NAS 

panel noted is a more conservative and health protective approach than using EPA’s traditional 

approach of relying on the no observed adverse effect level (NOAEL) [FN10: NAS at 169, (pdf 

version).], along with an additional safety factor applied to it, the quantifiable incremental risk would 

appear to be small. 

I hope you find these comments helpful; we would be happy to talk further with you about this 

important issue. Further, if the CHPAC opts to convene a public meeting on perchlorate, the PSG 

would welcome an opportunity to present the scientific literature and our public comments. For 

your convenience, we have included those comments for your review. Our comments review the 

science of perchlorate beginning with the comprehensive NAS review followed by subsequent 

studies and then apply them in the statutory and policy framework in which EPA has made its 

preliminary determination. Thank you for your time and attention. 

Sincerely, Michael Girard Chairman, Perchlorate Study Group cc: Marcus Peacock, Deputy 

Administrator Benjamin Grumbles, Assistant Administrator, Office of Water Cynthia Dougherty, 

Director, Office of Ground Water and Drinking Water Eric Burneson, Chief, Targeting and 

Analysis Branch 

Response: See response to comment ID 20657 under comment code 5300. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21090 
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EPA Comment Code: 5300 

 

Comment: Public water systems do not offer a meaningful risk reduction opportunity since EPA's 

data show that only a few percent of systems have had detectable levels of perchlorate and virtually 

all of them are routinely below EPA's unusually protective reference dose (RfD). EPA also has 

extensive data that show the US population's total exposure to perchlorate - from food and water - 

is below the RfD for 99.996 percent of the population. EPA should spend its limited resources on 

significant potential threats to human health in order to most effectively protect the public health. 

The comments below present a detailed analysis of the issues relating to EPA's determination. The 

attachment from Intertox describes in more detail the state of the scientific literature. The 

overwhelming weight of scientific evidence indicates that EPA is acting correctly in its 

determination not to establish a Federal drinking water standard. 

Response: See response to comment code 5200. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21097 

EPA Comment Code: 5300 

 

Comment: IV. The Scientific Literature Supports EPA's Findings that There is Not a Meaningful 

Opportunity for Risk Reduction from a National Drinking Water Standard 

The evaluation of data on the health effects of perchlorate, national occurrence, and exposure using 

the SDWA "meaningful risk reduction" criteria support EPA's determination that an NPDWR for 

perchlorate is unnecessary. 

Following the release of the NAS report, EPA set an RfD for perchlorate at 0.7 ug/kg-d. The RfD 

is defined as "...an estimate (with uncertainty spanning perhaps an order of magnitude) of a daily 

exposure to the human population (including sensitive subgroups) that is likely to be without an 

appreciable risk of deleterious effects during a lifetime (EPA, 2005). The RfD does not distinguish 

between perchlorate in drinking water and in food. In establishing the amount of perchlorate that 

would be expected to pose no risk to health in drinking water alone, the RSC is factored in resulting 

in the HRL or "the benchmark against which EPA compared the concentration of a contaminant 

found in public water systems to determine if it is at a level of public health concern (73 FR 60275)." 

EPA has established that it would not be meaningful to set an NPDWR, but is now considering 

issuing a Health Advisory (HA), in the form of an MCLG. 

If EPA decides a Health Advisory is necessary, the RfD is sufficiently conservative to serve as the 

HA. As presented in the PSG's comments on the May 1, 2007 notice, the best available scientific 

analysis demonstrates that all of EPA's approaches lead to an RSC of essentially one. Drinking water 

is not a meaningful contributor to total perchlorate exposure - and not even a minor source of total 

inhibition of iodine uptake, the non-adverse effect that is the basis of the RfD. 

Alternatively, the HRL identified in its preliminary determination could also serve as an even more 

conservative, but no more protective, HA. What is striking is that either approach would be highly 
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conservative. In fact, the high level of conservatism, and health protection, is far greater than EPA 

indicated by the agency's longstanding policies, themselves properly weighted toward greater 

protection. 

The HRL relies on the NAS-recommended RfD that has several levels of conservatism (that is, 

exceptional health protection) built into calculation of dose. As EPA has noted, its RfD was based 

upon the recommendations of the NAS which, as noted, used a much more conservative and 

health-protective approach to derive its recommended safe dose than EPA has previously 

used.[FN3: NAS, at 170-71.] EPA embeds an additional level of conservatism in calculating the final 

HRL by verifying their calculations using PBPK modeling of pregnant women as opposed to relying 

on the standard of assuming an adult as the focus of its calculations. 

To determine the RSC, the EPA uses the NHANES-UCMR data to estimate doses to people who 

were exposed through food only (73 FR 60273). The UCMR 1 shows the median concentration of 

perchlorate in drinking water to be 6.4 ug/L (73 FR 60269). The 90th percentile estimated dose to 

the women exposed only through food was 0.263 ug/kg/d which corresponds to 38% of the RfD. 

This leaves 62% of the RfD left for exposure through water. Using this data, a HRL was calculated 

as such: 

HRL = (RfD x BW / DWI) x RSC Where, RfD = 0.7 mg/kg-d BW = 70 kg DWI = drinking water 

intake = 2 L/d RSC = 62% 

This results in a HRL of 15 ppb. The derivation of the HRL was based on the body weight and 

water intake of an adult[FN4: The standard EPA default procedure for converting dose into 

drinking water equivalent levels assumes 2 liters (67.6 oz) of water consumed per day and a body 

weight of 70 kg (154 lbs). These default values are not symmetrically representative of the 

population. This water consumption (WC) default is approximately equal to the 88th percentile 

water intake for adults aged 20 through 64 (calculated from Table 3-11 of U.S. EPA's Exposure 

Factors Handbook; EPA, 1999). However, the default body weight of 70 kg is approximately equal 

to the 27th percentile of the distribution for adult males aged 18-74 and the 70th percentile of the 

distribution for adult females (from EPA, 1999; Tables 7-3 and 7-4).], not the pregnant woman and 

her fetus. The EPA modeled the amount of IUI in a pregnant woman and her fetus using PBPK 

modeling and found that the amount of IUI expected was equivalent to the NOEL from Greer et al. 

(2002). EPA then compares this HRL to perchlorate occurrence data in drinking water to evaluate 

the percent of the population exposed to perchlorate above the HRL. 

For the perchlorate determination, EPA may also use the evaluation criteria under the CCL 1 

regulatory determinations to determine whether a meaningful opportunity to regulate health risk 

exists. EPA's regulatory evaluation process follows the recommendations on a protocol from EPA's 

stakeholder advisory panel, the National Drinking Water Advisory Council (NDWAC). To assist 

EPA in evaluating the third statutory criteria, the NDWAC protocol recommended "that EPA 

consider estimating the national population exposed above half the health reference level (or 

benchmark) and the national population exposed above the health reference level (or benchmark)." 

EPA used this approach for evaluating substances in its CCL 1 regulatory determinations. This 

approach allows EPA's decision-making process to be replicated and therefore provides greater 

transparency and objectivity into the agency's final decisions rendered on the third statutory 

criterion. It also has the support of major stakeholders and has been subject to public comment. The 
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PSG points out that EPA could, in addition to its valid reasoning in the preliminary determination, 

relay a similar evaluation process for its perchlorate determination. 

A comparison of occurrence data for perchlorate and relevant compounds from EPA's CCL 1 

regulatory determinations and the CCL 2 determinations reveals that perchlorate ranks as a lower 

opportunity for risk reduction than the sodium, manganese, sulfate, and boron, all of four of which 

EPA has made determinations not to regulate. 

If the HRL is 15 ppb, EPA estimates that between 0.29 percent and 0.8 percent of PWSs have at 

least one detection greater than 15 ug/L, affecting 0.9 million to 2 million people served. Between 

1.14 percent and 2.12 percent of PWSs had at least one detect with concentrations at 1/2 of the 

HRL (7 ug/L), affecting between 0.8 percent and 2.5 percent of the population served or between 

2.2 million and 7.2 million people served, respectively. 

[Table 1: Comparison of Risk Opportunity between Perchlorate and Other Compounds - See PDF 

Docket ID EPA-HQ-OW-2008-0692-1855] 

The percentage of PWSs with perchlorate detections was very low (3.6 percent) compared to the 

next lowest unregulated compound, manganese at 68 percent. Sodium, for example, was detected in 

all PWSs. Perchlorate also has one of the lowest populations served by PWSs with detections above 

half the HRL with 2.2 million people. Perchlorate is well within the range of values for the 

evaluation criterion EPA uses. Like these other constituents, perchlorate is widely found in the diet 

and has minimal adverse health effects at the RfD. Although EPA's approach of using actual food 

data has more scientific justification, even if EPA adopts its customary approach for the proposed 

regulatory determination, it should find that perchlorate does not pose a meaningful opportunity to 

reduce risk. 

Response: See response to comment codes 5300 and 5200. EPA considered national occurrence 

and the severity of health effects from perchlorate and concluded that regulation was warranted, so 

EPA has determined that perchlorate should be subject to an NPDWR. The Agency plans to 

prepare and make available a regulatory health effects support document as part of its regulatory 

promulgation process. If an NPDWR is promulgated a health advisory will be unnecessary. EPA 

agrees with the commenter that the RfD is conservative and protective of health. 

Regarding the PBPK model, after further consideration of the peer review and public comments, 

EPA concludes that the PBPK modeling analysis, in the context of the perchlorate regulatory 

determination, is useful in examining which life stages are most susceptible to the effects of 

perchlorate. For example, the model indicates that a fetus may be seven times more sensitive to the 

effects of perchlorate than a pregnant woman. The model also allows for the estimation of the 

concentration of perchlorate in breast milk (thus breast-fed infant exposure) at various maternal 

perchlorate exposure levels. However, because of the stated limitations, EPA has decided the model 

does not directly bear on the current decision regarding the need for a NPDWR for perchlorate. 

EPA is continuing to evaluate whether the model could be used in setting a NPDWR for 

perchlorate. Regarding the suggestion to compare the risk opportunity from detects in public water 

systems between perchlorate and other compounds that EPA has decided not to regulate, EPA does 

not believe it's appropriate to factor these comparisons into the decision whether to regulate a 

contaminant. The Administrator will make these determinations on a case-by-case, contaminant 

specific basis. In making a regulatory determination, the Administrator considers the adverse health 

effect of the particular contaminant at issue as well as the occurrence or likelihood of occurrence of 
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the contaminant in public water systems with a frequency and at levels of public health concern. In 

addition, even if such comparisons were appropriate, the occurrence level of perchlorate at the levels 

of public concern identified by EPA are higher than most of the contaminants for which EPA has 

made a negative determination. Finally, it is the sole judgment of EPA’s Administrator to determine 

whether there is a meaningful opportunity to reduce health risk for persons served by public water 

systems. 

Commenter Name: Tigris Powers 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2244 

EPA Comment ID: 22427 

EPA Comment Code: 5300 

 

Comment: All Americans deserve healthy and clean drinking water. The EPA should not finalize 

this decision until the scientific review is complete and should make decisions that are consistent 

with the agency's own scientists. Contrary to your claims, protecting the health of young children is 

indeed a "meaningful opportunity for health risk reduction." 

Sincerely, Tigris Powers 2421 Topanga Skyline Drive Topanga, CA 90290 

Response: See response to comment code 5300. 

Commenter Name: Kraig Erickson 

Commenter Organization: RMC Water and Environment (RMC) 

EPA Document ID: EPA-HQ-OW-2008-0692-2299 

EPA Comment ID: 24979 

EPA Comment Code: 5300 

 

Comment: All Americans deserve healthy and clean drinking water. The EPA should not finalize 

this decision until the scientific review is complete and should make decisions that are consistent 

with the agency's own scientists. Contrary to your claims, protecting the health of young children is 

indeed a "meaningful opportunity for health risk reduction." 

Again, I urge you to reverse your decision and to set a national drinking water standard for 

perchlorate. 

Response: See response to comment code 5300. 

Commenter Name: Ed Thomas 

Commenter Organization: National Rural Water Association (NRWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0521 

EPA Comment ID: 28476 

EPA Comment Code: 5300 

 

Comment: In this time of severe economic stress in our society, it is particularly important that the 

benefits of a regulation be carefully weighed against the costs and only those with an overriding 

benefit/cost advantage be promulgated. For perchlorate it is clear that this advantage does not exist 

uniformly and in fact, for some communities the aforementioned reference provides evidence that 
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the adverse health effects caused by the cost of the regulation may equal or outweigh the projected 

benefits. 

Rubin, etal (see reference 1 electronic attachment - "Rubin trade off health risk final.pdf") have 

documented quantitative evidence that when regulatory costs increase in the order of $25 per 

month, significant numbers of customers are forced into spending choices that have health 

outcomes that may outweigh the projected benefits of the regulation. NRWA strongly feels that 

when evaluating whether a regulation will result in a meaningful health benefit, EPA must take these 

effects into consideration. This is essentially an affordability issue and NRWA recommends that 

EPA include appropriate affordability criteria in its final determination to not regulate perchlorate. 

Response: See response to comment ID 20272 under comment code 5300. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28874 

EPA Comment Code: 5300 

 

Comment: c) The SDWA requires that the regulation of such contaminants must present a 

meaningful opportunity for health risk reduction for persons served by public water systems. For 

perchlorate, no possible health benefit can occur when estimated exposure levels are below the 

NOEL for a nonadverse effect. Further, EPA adjusted the NOEL ten-fold lower to derive the RfD 

to account for sensitive subpopulations. 

Response: See reponse to comment code 5200, comment ID 21028. 

Commenter Name: Danielle Blacet 

Commenter Organization: Association of California Water Agencies 

EPA Document ID: EPA-HQ-OW-2009-0297-0208 

EPA Comment ID: 28922 

EPA Comment Code: 5300 

 

Comment: 4) ACWA believes that the maximum contaminant levels (MCLs) established in 

Massachusetts and California have significantly reduced the current public exposure to perchlorate 

in drinking water. ACWA feels this has had an impact on the meaningful opportunity for health risk 

reduction that is available through a national drinking water standard for perchlorate. 

Response: EPA acknowledges that there may be sources that had detected perchlorate from 

UCMR1 monitoring are either no longer being used or are being treated per the requirements of 

maximum contaminant levels established in California and Massachusetts; however, the 1996 

amendments to the Safe Drinking Water Act require the Agency to consider the best available, peer 

reviewed science when developing drinking water standards. In applying these principles, "best 

available" usually refers to the availability at the time an assessment is made. See response to 

comment code 5300. 

Commenter Name: Lucy Allen 

Commenter Organization: Pacific Institute 
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EPA Document ID: EPA-HQ-OW-2008-0692-1770 

EPA Comment ID: 29099 

EPA Comment Code: 5300 

 

Comment: We understand the need to balance costs and benefits in drinking water regulations, 

however, costs associated with the regulation of perchlorate will ostensibly be low, except in those 

cases where high levels of perchlorate exist and drinking water must be treated. For other systems, 

costs can be limited to periodic monitoring (e.g., once in every 4 years, as is done with 

radionuclides). The cost of regulating perchlorate in our country’s public drinking water, when 

compared with the myriad potential health-related costs, including added pressure on public health 

care systems, missed work and school days due to sickness, etc., may very likely prove the most costeffective option. 

In light of these concerns we sincerely hope that the EPA reevaluates its Preliminary Decision, 

taking into account the impact of this regulation on all vulnerable populations, the potential for 

remediation efforts, and the potential future contamination of drinking water. In addition, we hope 

that the agency fulfills its duty to protect the public health of the thousands of individuals who are 

affected by unsafe perchlorate exposure through public drinking water. 

Sincerely, Lucy Allen Research Analyst Pacific Institute 

Courtney Smith Research Analyst Pacific Institute 

Response: Regarding the costs associated with regulating perchlorate, see response to comment ID 

20272 under comment code 5300. Regarding EPA reevaluating its preliminary decision, see response 

to comment code 5300. 

 
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EPA Comment Code: 6000 EPA Actions 

Individual Comments 

Commenter Name: Stephen Haterius 

Commenter Organization: The National Association of State Departments of Agriculture 

(NASDA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0500 

EPA Comment ID: 28485 

EPA Comment Code: 6000 

 

Comment: The significance of this issue goes far beyond setting unwise regulatory precedent. An 

overly conservative perchlorate standard that is not based on sound, peer-reviewed science and an 

appropriate risk-based assessment could unintentionally lead to unjustified food scares on a wide 

variety of fresh fruits, vegetables, and dairy products. Food scares of this nature could where 

particular commodities are "black listed" without regard to science would have devastating economic 

impacts on agriculture producers and processors. Finally, the economic impacts associated with 

unfounded concerns over traces of perchlorate in food could lead to the relocation of agricultural 

production to countries that have food safety standards that are significantly lower than in the 

United States. 

We appreciate your attention to our concerns and once again encourage you to extend the comment 

period for an additional 30 days. 

Sincerely, Stephen Haterius Executive Director 

Response: EPA believes that perchlorate meets the specific criteria for regulating a contaminant in 

Section 1412(b)(1)(A) of the Safe Drinking Water Act and therefore has determined that EPA 

should regulate perchlorate in drinking water. EPA discusses this conclusion in more detail in 

today’s perchlorate Federal Register notice. EPA agrees that perchlorate is more widespread in foods 

than in public water systems, but EPA does not believe that the widespread presence of perchlorate 

in food overrides the opportunity for public health risk reduction for persons served by public water 

systems with perchlorate contamination. EPA’s action considers the presence of perchlorate in food 

but would not impose regulatory requirements on perchlorate in food. Regulation of perchlorate in 

foods is outside the scope of this determination which is made under the authority found in the Safe 

Drinking Water Act, as amended in 1996. 

 
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EPA Comment Code: 6100 EPA’s preliminary determination not to regulate 

perchlorate 

Individual Comments 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 28743 

EPA Comment Code: 6100 

 

Comment: September 16, 2009 

U.S. Environmental Protection Agency Mailcode 2822T 1200 Pennsylvania Ave., NW. Washington, 

DC 20460 

Subject: Docket ID No. EPA-HQ-OW-0297 

Reference: Drinking Water: Perchlorate Supplemental Request for Comments (Federal Register / 

Vol. 74, No. 1591 Wednesday, August 19, 2009 / Notices 

Attached, please find comments provided by the Nevada Division of Environmental Protection 

(NDEP) in response to the referenced "Supplemental Request for Comments" noticed by the U.S. 

Environmental Protection Agency (EPA) in the August 19, 2009 Federal Register; Docket ID No. 

EPA-HQ-OW-2009-0297. These comments are provided to assist the EPA in their efforts in 

evaluating whether there is a meaningful opportunity for human health risk reduction of perchlorate 

through a national primary drinking water rule. 

The NDEP understands that in order to regulate a contaminant in drinking water [i.e., develop a 

maximum contaminant level (MCL)], EPA must determine that the contaminant meets the 

following three criteria: 

1) The contaminant may have an adverse effect on human health; 

2) The contaminant is known to occur (or there is a substantial likelihood that the contaminant will 

occur) in public water systems, with a frequency and at levels of public health concern; and 

3) Regulation of such a contaminant presents a meaningful opportunity for health risk reduction for 

persons served by public water systems 

The NDEP believes that the EPA cannot reliably demonstrate that all three criteria can be met (with 

respect to perchlorate) when all of the studies and available literature are used and new occurrence 

data are collected to inform the decision. Many studies have been conducted and the results peer 

reviewed and published since the National Academy of Science (NAS), National Research Center 

(NRC) provided their review in 2005. A number of these studies were conducted explicitly to fill 

data gaps present at that time. A thoughtful review of the entirety of the studies and literature, 

coupled with collection and analysis of up-to-date occurrence data, is recommended to allow EPA 

to meet its charge on this important decision. 
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Response: EPA has continued to review all the available data published concerning perchlorate in 

drinking water as it is made available. The regulatory determination made in today's Federal Register 

notice was based upon a consideration of the best available peer reviewed science and data, both 

recent as well as the information available and discussed in earlier Federal Register notices. 

 
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EPA Comment Code: 6110 Comments urging EPA not to regulate perchlorate 

Response to Code 6110: After review of the available science, data and public comments, EPA has 

determined that perchlorate may have an adverse effect on the health of persons and that 

perchlorate is known to occur or there is a substantial likelihood it occurs in public water supply 

systems with frequency and at levels of public health concern. EPA has also determined that 

regulation of perchlorate presents a meaningful opportunity to reduce health risk for persons served 

by public water systems. The basis for EPA’s determination is described in the Federal Register 

Notice for the final regulatory determination. 

Individual Comments 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group (PSG) 

EPA Document ID: EPA-HQ-OW-2007-0068-0168 

EPA Comment ID: 20278 

EPA Comment Code: 6110 

 

Comment: July 2, 2007 

US Environmental Protection Agency Office of Water Docket (Mailcode 2822T) 1200 Pennsylvania 

Avenue, NW Washington, DC 20460 

RE: Comments on Regulatory Determinations Regarding Contaminants on the Second Drinking 

Water Contaminant Candidate List Rule Docket EPA-HQ-OW-2007-0068 

The Perchlorate Study Group (PSG) is pleased to submit comments to EPA on Docket ID No. 

EPA-HQ-OW-2007-0068, entitled Drinking Water: Regulatory Determinations Regarding 

Contaminants on the Second Drinking Water Contaminant Candidate List- Preliminary 

Determinations; Proposed Rule.[FN1: 72 Fed. Reg. 24015 (2007) (proposed May 1, 2007).] 

The PSG is committed to ensuring that the best available science is made available in public debate 

and in the subsequent setting of regulatory standards.[FN2: In section 1412(b)(3)(A) of the 1996 

Amendments to the Safe Drinking Water Act, Congress required EPA to use the best available 

science and data: "The Administrator shall use: (i) the best available, peer-reviewed science and 

supporting studies conducted in accordance with sound and objective scientific practices; and (ii) 

data collected by accepted methods or best available methods (if the reliability of the method and 

the nature of the decision justifies use of the data).] The member companies of the PSG include 

Aerojet, AMPAC, ATK, and Tronox. 

The PSG has worked cooperatively and effectively with the US Environmental Protection Agency 

(EPA) and other federal agencies, state governments, water purveyors, and other business 

organizations to: 

* increase scientific and medical understanding of perchlorate’s possible effects on human health; 

and, 

* assess the level of perchlorate in drinking water that will pose no cognitive risk. 
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In seeking public comment on its Second Contaminant Candidate List (CCL 2) Preliminary 

Determinations, EPA has expressed particular interest in receiving information regarding the 

adequacy of available occurrence and exposure data with respect to making a regulatory 

determination for perchlorate. In addition, EPA has asked for public input on scientific analysis 

options that would assist the Agency in reaching a regulatory determination for perchlorate. 

The PSG members are manufacturers and users of perchlorate who are actively remediating areas of 

past releases, and are citizens concerned with the protection of the public’s health. As such, the PSG 

member companies have a strong and unique commitment to ensuring that the best available 

science is applied in regulatory decision making. 

Based on its thorough evaluation of the best available science, as well as consideration of the 

Agency’s statutory authorities, the PSG respectfully submits: 

* in light of the National Academy of Sciences comprehensive review, as well as numerous, peerreviewed studies, the Agency has more than sufficient data on perchlorate’s human health effects to 

make a regulatory determination for perchlorate on an expedited basis; and 

* the extensive scientific record indicates that establishing a drinking water standard for perchlorate 

would not yield a meaningful opportunity to reduce risk to human health, as required under the Safe 

Drinking Water Act. 

ANALYSIS AND OBSERVATIONS 

EVALUATING THE 3 STATUTORY CRITERIA FOR THE REGULATORY 

DETERMINATION PROCESS 

To determine whether to regulate a contaminant with a Federal drinking water standard, EPA 

evaluates three Safe Drinking Water Act criteria.[FN3: In section 1412(b)(1)(A) of the Safe Drinking 

Water Reauthorization Act of 1996, Congress established three criteria for use by EPA in making 

drinking water regulatory determinations: (i) the contaminant may have an adverse effect on the 

health of persons; (ii) the contaminant is known to occur or there is a substantial likelihood that the 

contaminant will occur in public water systems with a frequency and at levels of public health 

concern; and, (iii) in the sole judgment of the Administrator, regulation of such contaminant 

presents a meaningful opportunity for health risk reduction for persons served by public water 

systems. (See, 110 Stat. 1613, 1619; 42 USC. §300g-1(b)(1)(B)(ii)(II)).] EPA has determined that it 

must make an affirmative determination on all three criteria to move forward with regulation. If the 

Agency determines that a regulation is appropriate, EPA can make its regulatory determination for 

perchlorate in two ways: 

1. through its longstanding approach used in the CCL 1 rulemaking and proposed for the CCL 2 

determinations; or, 

2. applying supplemental or alternative approaches reflecting new scientific information, using the 

uniquely conservative derivation of the perchlorate reference dose (RfD) for perchlorate, as well as 

the exceptionally deep and authoritative scientific literature on toxicity and population exposure. 
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No matter which approach EPA takes, the best available science runs inevitably to the conclusion 

that a perchlorate standard will not yield a meaningful opportunity to reduce risk to human health as 

required by the Safe Drinking Water Act. 

EPA has more than sufficient data on perchlorate’s human health effects as well as on occurrence 

and exposure to make a determination on perchlorate without delay. EPA is to be commended for 

its efforts to obtain public comment relating to the prospective use of supplemental or alternative 

approaches. These approaches are scientifically rigorous and upto- date, based on the peer- reviewed 

literature. Our collective goal of applying the best available science would point toward their use. 

Nonetheless, should the agency elect to apply an approach based strictly on toxicology and modeled 

exposures, we anticipate it will yield the same conclusions, albeit, after a period of unnecessary delay. 

Response: Please see the response to comment code 6110. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group (PSG) 

EPA Document ID: EPA-HQ-OW-2007-0068-0168 

EPA Comment ID: 20283 

EPA Comment Code: 6110 

 

Comment: CONCLUSION 

In summary, EPA has an extraordinary wealth of comprehensive, authoritative scientific information 

relating to perchlorate’s health effects, supplemented by extensive occurrence and exposure data. 

The Agency is therefore exceptionally well-positioned to issue a wellconsidered regulatory 

determination. 

In this case, the Agency can rely on the scientific review by the NAS and its own subsequent analysis 

in setting a reference dose pursuant to the NAS Report. Subsequent, peer-reviewed studies provide 

additional information that corroborates the conclusions of the NAS and EPA. 

The Agency can use its RfD as the HRL. EPA should take into account that the RfD is based on an 

unusually conservative point of departure, a NOEL (as opposed to the Agency’s customary No 

Observed Adverse Effect Level), with an added safety factor of 10. 

Ultimately, regardless of which approach EPA takes, the best available scientific data supports a 

determination that there is not a meaningful opportunity for risk reduction as required by the Safe 

Drinking Water Act. 

The Perchlorate Study Group appreciates the opportunity to submit comments on this issue. If you 

have any questions regarding these comments, please do not hesitate to contact Michael Girard at 

(916) 355-2945. 

Sincerely, Michael Girard The Perchlorate Study Group Attach: 

[Attachment 1 - see PDF] [Attachment 2 - see PDF] [Attachment 3 - see PDF] [Attachment 4 - see 

PDF] [Attachment 5 - see PDF] 
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Response: Please see the response to comment code 6110. In light of the discussion presented in 

the final regulatory determination notice and the information available at this time, EPA expects to 

select an MCLG from among the range of potential alternative HRLs in the August 9, 2009 notice 

(74 FR 41883). These levels range from 1 μg/L to 47 μg/L and are the concentrations of perchlorate 

in drinking water that may result in total perchlorate exposures (from food and water) greater than 

the RfD for individuals in each life stage. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association 

EPA Document ID: EPA-HQ-OW-2008-0692-1424 

EPA Comment ID: 20437 

EPA Comment Code: 6110 

 

Comment: November 10, 2008 U.S. Environmental Protection Agency Office of Water Docket 

(Mailcode 2822T) 1200 Pennsylvania Ave. NW Washington, DC 20460 

RE: Drinking Water: Preliminary Regulatory Determination on Perchlorate Docket EPA-HQ-OW2008-0692 

The American Water Works Association appreciates the opportunity to comment on the preliminary 

regulatory determination for perchlorate as detailed in the October 10, 2008 Federal Register notice 

(73 FR 60262). AWWA is an international, nonprofit, scientific and educational society dedicated to 

the improvement of drinking water quality and supply. Founded in 1881, the Association is the 

largest organization of water supply professionals in the world. Our 60,000 plus members represent 

the full spectrum of the drinking water community: treatment plant operators and managers, 

environmental advocates, engineers, scientists, academicians, and others who hold a genuine interest 

in water supply and public health. Our membership includes more than 4,700 utilities that supply 

roughly 80 percent of the nation's drinking water. Based on this broad membership base, these 

comments should be considered as representative of the drinking water community in general. 

AWWA has always been a strong' advocate of the process established under Section 1412(b) of the 

1996 SDWA Amendments to ensure that appropriate and scientifically based standards are 

developed and enforced by the Agency. The SDWA defined three (3) key criteria for identification 

of contaminants for potential regulation: 

i.the contaminant may have an adverse effect on the health of persons; 

ii.the contaminant is known to occur or there is a substantial likelihood that the contaminant will 

occur in public water systems with a frequency and at levels of public health concern; and 

iii.in the sole judgment of the Administrator, regulation of such contaminant presents a meaningful 

opportunity for health risk reduction for persons served by public water systems. 

Based on these SDWA criteria and currently available, AWWA supports EPA's proposed regulatory 

determination for perchlorate: Additionally, AWWA supports the EPA decision to issue a Health 

Advisory for perchlorate at the time of the final determination which provides important technical 

guidance to Federal agencies, State governments, and other public health officials. 
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The above conclusion is supported by independently developed assessments of both occurrence and 

exposure commissioned by AWWA. This research supports the finding that a national standard for 

perchlorate would not present a meaningful opportunity for health risk reduction for persons served 

by public water systems. The following provides a summary of our findings which are in the process 

of being submitted for peer-review. 

Response: Please see the response to comment code 6110. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association 

EPA Document ID: EPA-HQ-OW-2008-0692-1424 

EPA Comment ID: 20442 

EPA Comment Code: 6110 

 

Comment: Conclusion 

Based on our own analysis and related data presented in the proposed decision, AWWA believes 

that EPA's decision is supported by the criteria established in the SDWA. AWWA appreciates the 

opportunity to comment on these important drinking water issues. If you have any questions about 

these comments, please feel to call Kevin Morley or me in our Washington Office at 202-628-8303. 

Yours Sincerely, Thomas W. Curtis Deputy Executive Director 

cc: Benjamin Grumbles - USEPA OW Cynthia Dougherty - USEPA OGWDW Eric Burneson - 

USEPA OGWDW Brian Mannix - USEPA OPEI Alan Roberson Kevin Morley 

References 

Blount BC, Valentin-Blasini L, Osterloh JD, Mauldin JP, Pirkle JL. (2006) Perchlorate exposure of 

the U.S. population, 2001-2002. Journal of Exposure Science and Environmental Epidemiology 

17(4):400-7. 

Brandbuber, Phillip, Clark, Sarah and Morley, Kevin M. (pending publication in Journal AWWA ). 

The Occurrence of Perchlorate in Public Drinking Water Systems. 

Crawford-Brown, Doug, Raucher, Bob and Harrod, Megan. 2006. Inter- Subject Variability of Risk 

From Perchlorate in Community Water Supplies. Environmental Health Perspectives 114:7:975. 

Mendez, William and Dederick, Elizabeth (2008). Estimating the Contribution of Drinking Water to 

Aggregate Perchlorate Intake of Reproductive Age Women in the U.S. Report prepared for the 

American Water Works Association, see enclosed Appendix A. 

Appendix A: Estimating the Contribution of Drinking Water to Aggregate Perchlorate Intake of 

Reproductive Age Women in the U.S. 

Response: Please see the response to comment code 6110. 
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Commenter Name: Colby Goodliffe 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1515 

EPA Comment ID: 20504 

EPA Comment Code: 6110 

 

Comment: I recommend that EPA should not change its determination regarding the regulation of 

perchlorate. There is no need for every public water system in the US to test for a contaminant that 

only a few water sources contain. Let the states handle this on a case-by-case basis. I manage a 

public water system and we already spend thousands of dollars each year to test for contaminants 

that are not in our water and never have been in our water. I agree that we need to do as much as 

possible to ensure that our drinking water is safe, but the blanket regulations that govern drinking 

water are ineffective and facilitate wasteful spending of tax dollars. 

Colby Goodliffe 

Response: Please see the response to comment code 6110. The Agency analyzed occurrence data 

from the Unregulated Contaminant Monitoring Rule (UCMR), which is nationally representative, 

and found that perchlorate occurred in 26 states and 2 territories. Today’s determination merely 

initiates the process of establishing a national primary drinking water regulation. It does not impose 

any requirements on public water systems. EPA will provide an opportunity to comment on the 

proposed regulation, along with health risk reduction and cost analysis, feasibility analysis, and other 

relevant analyses. 

Commenter Name: Ed Thomas 

Commenter Organization: National Rural Water Association 

EPA Document ID: EPA-HQ-OW-2008-0692-1669 

EPA Comment ID: 20617 

EPA Comment Code: 6110 

 

Comment: November 10, 2008 

U.S. Environmental Protection Agency Office of Water Docket (Mailcode 2822T) 1200 

Pennsylvania Ave. NW Washington, DC 20460 

RE: Drinking Water: Preliminary Regulatory Determination on Perchlorate (Docket Number: EPAHQ-OW-2008-0068) 

To Whom It May Concern: 

NRWA commends EPA for their proposed regulatory determination for perchlorate. We believe the 

Agency has relied on sound science and that a national standard for perchlorate would not result in a 

meaningful opportunity for health risk reduction. 

Response: EPA believes that regulating perchlorate in drinking water presents a meaningful 

opportunity for health risk reduction. This determination is based on the best available peer 

reviewed science and data collected in accordance with accepted methods related to perchlorate’s 

occurrence in drinking water, the presence of perchlorate in foods and the potential health effects of 
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exposure to perchlorate, and EPA’s population exposure evaluation as described in more detail in 

the final regulatory determination. 

Commenter Name: Ed Thomas 

Commenter Organization: National Rural Water Association 

EPA Document ID: EPA-HQ-OW-2008-0692-1669 

EPA Comment ID: 20619 

EPA Comment Code: 6110 

 

Comment: In this time of severe economic stress in our society, it is particularly important that the 

benefits of a regulation be carefully weighed against the costs and only those with an overriding 

benefit/cost advantage be promulgated. For perchlorate it is clear that this advantage does not exist 

uniformly and in fact, for some communities the aforementioned reference provides evidence that 

the adverse health effects caused by the cost of the regulation may equal or outweigh the projected 

benefits. 

Response: EPA believes that regulating perchlorate in drinking water presents a meaningful 

opportunity for health risk reduction. EPA believes that regulating perchlorate in drinking water 

presents a meaningful opportunity for health risk reduction. This determination is based on the best 

available peer reviewed science and data collected in accordance with accepted methods related to 

perchlorate’s occurrence in drinking water , the presence of perchlorate in foods and the potential 

health effects of exposure to perchlorate, and EPA’s population exposure evaluation as described in 

more detail in the final regulatory determination. EPA has not performed a cost/benefit analysis for 

this final determination. EPA will perform such an analysis, as required by SDWA § 1412(3)(C), for 

the proposed regulation. The Agency has analyzed occurrence data from the Unregulated 

Contaminant Monitoring Rule (UCMR), which is nationally representative, and found that 

perchlorate occurred in 26 states and 2 territories affecting millions of people 

Commenter Name: Michael Dourson 

Commenter Organization: Toxicology Excellence for Risk Assessment 

EPA Document ID: EPA-HQ-OW-2008-0692-1562 

EPA Comment ID: 20640 

EPA Comment Code: 6110 

 

Comment: Acknowledgements 

The authors have collectively studied the toxicity of perchlorate since 1991 on behalf of US EPA 

and the nonprofit corporation Toxicology Excellence for Risk Assessment (TERA) at the request of 

the Perchlorate Study Group. Opinions expressed in this commentary, however, reflect solely those 

of the authors and not of any organization or other individual. Resources to support this technical 

commentary were provided by the Perchlorate Study Group, based in part on work supported by 

the developmental reserve fund of TERA. 

Summary 

We agree with EPA’s decision to not regulate perchlorate on a national level at this time. Although 

the data do provide support for the conclusion that at sufficiently high doses, perchlorate may have 

adverse effects on sensitive groups within the US population, we agree with EPA’s analysis that 
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perchlorate is not occurring in the public water supply at levels that cause concern for health risks. 

In particular, EPA’s analysis of relative source contribution based on the FDA Total Diet Study and 

estimates of exposure based on the NHANES/UCR data give an excellent understanding of the 

potential for exposure for pregnant women, the sensitive population for perchlorate exposure. 

Response: Please see the response to comment code 6110. As the federal register notice explains in 

greater detail, EPA has determined that, pursuant to the NRC’s findings, infants and developing 

children are additional sensitive populations. 

Commenter Name: Michael Dourson 

Commenter Organization: Toxicology Excellence for Risk Assessment 

EPA Document ID: EPA-HQ-OW-2008-0692-1562 

EPA Comment ID: 20643 

EPA Comment Code: 6110 

 

Comment: Conclusion 

In this Federal Register notice, EPA is making a preliminary regulatory determination that a national 

primary drinking water rule is not necessary for perchlorate because a national primary drinking 

water regulation would not provide a meaningful opportunity to reduce health risk. In addition, 

EPA is announcing its plans to publish a Health Advisory, which will provide Federal, Regional, 

State, and Local public health officials with information regarding health risks posed from 

perchlorate-contaminated drinking water. Based on EPA’s analysis of exposure data and relative 

source contribution, we agree that perchlorate is not occurring in the public water supply at levels 

that cause concern for health risks. However, we also recommend that EPA update its RfD prior to 

publishing a Health Advisory for the following reasons: 

* Additional important data on pregnant women and their offspring have become available since the 

time of the development of the EPA’s RfD in 2005, which necessitate a reconsideration of the 

existing value. This reconsideration is consistent with recommendations of the NAS (2005) in its 

report. 

* The excellent relative source contribution evaluation of EPA, based on well supported and clearly 

described work of the FDA, necessitates a rethinking of the any RfD, since the underlying studies 

may not have measured perchlorate in the food of the human subjects. 

* The 2005 "RfD" of the NAS does not follow the existing EPA method. 

References 

Barnes DG, Dourson ML. 1988. Reference dose (RfD): Description and use in health risk 

assessments. Regul Toxicol Pharmacol 8: 471-486. 

Environmental Protection Agency. 2002. A review of the Reference Dose (RfD) and Reference 

Concentration (RfC) processes. Risk Assessment Forum. EPA/630/P- 02/002F, December. 

Environmental Protection Agency. 2008. Integrated Risk Information System (IRIS). Online at 

www.epa.government/iris. 
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Faustman EM, Omenn GS. 2001. Risk Assessment. In: Casarett and Doull’s Toxicology: The Basic 

Science of Poisons (Klaassen CD, ed.). 6th Edition. McGraw-Hill, 92. 

Lehman, A.J. and O.G. Fitzhugh. 1954. 100-fold margin of safety. Assoc. Food Drug Off. U.S.Q. 

Bull. 18:51-58. 

National Research Council/National Academy of Sciences (NRC/NAS). 2005. Health Implications 

of Perchlorate Ingestion. NAS Press, Washington D.C. 

Strawson J, Zhao Q, Dourson M. 2004. Reference Dose for Perchlorate Based on Thyroid 

Hormone Change in Pregnant Women as the Critical Effect. Regulatory Toxicology and 

Pharmacology 39: 44-65. 

Tellez RT, Chacon PM, Gibbs J, Crump C, Abarca CR. 2005. Chronic Environmental Exposure To 

Perchlorate And Thyroid Function During Pregnancy And The Neonatal Period. THYROID: 15(9): 

963-975. 

Response: Please see the response to comment code 6110. In a NRC 2005 review of the state of 

the sciences regarding potential perchlorate adverse health effects and mode-of-action (“Health 

Implications of Perchlorate Ingestion”, NRC (2005)), the NRC recommended that data from the 

Greer et al. (2002) human clinical study be used as the basis for deriving a perchlorate reference dose 

(RfD) (NRC 2005). From this Greer et al. (2002) human clinical study, the statistical no observed 

effect level (NOEL) for the perchlorate-induced inhibition of thyroid iodide uptake was determined 

to be 7.0 ug/kg, which corresponded to an iodide uptake inhibition of 1.8%. NRC concluded that 

the most health protective and scientifically valid approach to deriving a reference dose for 

perchlorate, was to base the perchlorate RfD on the inhibition of iodide uptake by the thyroid, and 

that iodide uptake inhibition, though not an adverse effect per se, is the most appropriate precursor 

event, and would precede any more severe adverse health effects of perchlorate exposure in humans. 

The NRC recommended basing the RfD on a precursor to an adverse effect rather than an adverse 

effect, per se. In this case, NRC used prevention of iodide uptake inhibition, a precursor to adverse 

thyroid effects, to establish a level at which no adverse effects would be anticipated in exposed 

populations. This approach is consistent with the Agency’s policy on the use of precursor events 

when appropriate in establishing the critical effect upon which an RfD is based (U.S. EPA, 2002). 

The NRC recommended that EPA apply an uncertainty factor of 10 to this NOEL of 7.0 ug/kg for 

the perchlorate-induced inhibition of thyroid iodide uptake, to account for differences in sensitivity 

between healthy adults and the most sensitive sub-population, consisting of fetuses of pregnant 

women who might have hypothyroidism or iodide deficiency. EPA has also considered data derived 

from the Tellez et al. (2005) study. Blood serum perchlorate concentrations predicted through 

PBPK modeling from data from a study of school children in Chile (Tellez et al. 2005) were within 

the range of the measured concentrations, and the concentrations of perchlorate in breast milk 

predicted from the model were within two standard deviations of the measured concentrations. 

Therefore, PBPK modeling predictions of blood serum perchlorate concentrations were consistent 

with empirical results, and the predicted extent of iodide inhibition in the most sensitive population 

(the fetus), based in part on data from Tellez et al. (2005), was not found to be significant at EPA’s 

RfD of 0.7 ug/kg/day. 
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EPA agrees that additional important data have become available since the RfD was derived in 2005. 

However, EPA has evaluated the new data and has decided to make the regulatory determination 

based upon the current RfD. EPA will continue to evaluate any new perchlorate data to determine 

its relevance to the regulatory determination in accordance with the SDWA. 

Greer MA, Goodman G, Pleus RC, Greer SE. Health effects assessment for environmental 

perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake in 

humans. Environ Health Perspect. 2002 Sep;110(9):927-37. Erratum in: Environ Health Perspect. 

2005 Nov;113(11):A732. National Research Council (NRC). 2005. Health Implications of 

Perchlorate Ingestion. National Academies Press, Board on Environmental Studies and Toxicology, 

January, 2005, Washington, D.C. 276pp. Téllez RT, Chacón PM, Abarca CR, Blount BC, Van 

Landingham CB, Crump KS, Gibbs JP. Long-Term Environmental Exposure to Perchlorate 

Through Drinking Water and Thyroid Function During Pregnancy and the Neonatal Period. 

Thyroid. 2005 Sep;15(9): 963-75.USEPA. 2002. A review of the reference dose and reference 

concentration processes. Risk Assessment Forum, Washington, DC; EPA/630/P–02/0002F. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1748 

EPA Comment ID: 20653 

EPA Comment Code: 6110 

 

Comment: P.O. Box 13222 Sacramento, CA 95813 November 18, 2008 

Dr. Deborah L. Swackhamer, Chair Science Advisory Board Environmental Protection Agency 

Dr. Joan Rose Chair SAB Drinking Water Committee Environmental Protection Agency 

Dear Dr. Swackhamer and Dr. Rose: 

We read with great interest your November 5, 2008 letter to Administrator Johnson concerning 

EPA’s preliminary determination on a national drinking water standard for perchlorate. This letter 

states that "the SAB strongly believes that there must be a compelling scientific basis to support a 

determination not to regulate perchlorate..." We completely agree. Through the efforts of EPA’s 

Office of Water, Office of Solid Waste and Emergency Response, and Office of Research and 

Development over the last decade, the Agency has developed this compelling scientific basis. 

First, the overall scientific literature concerning perchlorate’s potential effects on human health is 

extensive. There are very few compounds subject to EPA regulation that can rest on multiple pillars 

of scientific evidence, including animal studies in multiple species, occupational studies, 

environmental epidemiology studies, and human clinical trials. There are also very few compounds 

in which the mechanism of action is clear and occurs with welldefined, non-adverse precursors. 

And, there are very few compounds that have been subject to a rigorous and comprehensive 

National Academy of Sciences (NAS) review of the health effects. 

As the NAS panel stated, unless these precursor effects occur, the subsequent adverse effects will 

not occur. To cite the NAS report, 
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The committee emphasizes that inhibition of iodide uptake by the thyroid has been the only 

consistently documented effect of perchlorate exposure in humans. The continuum of possible 

effects of iodide-uptake inhibition caused by perchlorate exposure is only proposed and has not 

been demonstrated in humans exposed to perchlorate (with the exception that in patients with 

hyperthyroidism doses of 200 mg daily or higher may reduce thyroid secretion). More important, the 

outcomes at the end of the continuum are not inevitable consequences of perchlorate 

exposure.[FN1: National Academy of Sciences, Health Implications of Perchlorate Ingestion, 2005, 

at 165 (pdf version). The noted dose of 200 mg/d is a conservative therapeutic value. When use of 

perchlorate to treat hyperthyroidism was common, doses of 400 mg/d were commonly prescribed, 

but were found to be slow to control thyrotoxicity and doses needed to be repeated 4 to 5 times/d, 

due to the rapid excretion of the drug. Although it still took an average of 9.4 weeks, doses of up to 

2000 mg/d were given to reduce hyperthyroidism to a remission state (Wolff, 1998).] 

Although no longer the drug of choice in the clinic for treating thyrotoxicosis, perchorate is still 

used medically. For example, perchlorate is used to treat amiodarone (an antiarrhythmetic agent) 

induced thyrotoxicosis.[FN2: 2 J. Wolff, Perchlorate and the Thyroid Gland, Pharmacol Rev. 1998; 

50(1):89-105.] In other words, except for its deliberate medical use, exposure to perchlorate has not 

been shown to have caused reduced thyroid function in humans. In addition to the NAS 

conclusions, newer studies indicate that exposures to perchlorate at environmentally relevant levels 

have not been demonstrated to cause any effect on the health of persons.[FN3: See, Benjamin C. 

Blount, et al., Perchlorate Exposure of the US Population, 2001-2002, J Expos. Sci Envtl Epidem. 

2006c; Benjamin C. Blount et al., Urinary Perchlorate and Thyroid Hormone Levels in Adolescent 

and Adult Men and Women Living in the United States, Envtl Health Perspect., 2006b, 1865-71; 

Rafael Tellez Tellez et al., Chronic Environmental Exposure to Perchlorate Through Drinking 

Water and Thyroid Function During Pregnancy and the Neonatal Period, Thyroid, 2005, 963-975; 

Yona Amitai et al., Gestational Exposure to High Perchlorate Concentrations in Drinking Water and 

Neonatal Thyroxine Levels, Thyroid, 2007, 843-850; Craig Steinmaus et al., Impact of Smoking and 

Thiocyanate on Perchlorate and Thyroid Hormone Associationsin the 2001-2002 National Health 

and Nutrition Examination Survey, Envtl Health Perspect, 2007, 1333-38.] The weight-of-evidence 

suggests that adverse effects do not occur following chronic exposures to perchlorate at doses much 

greater than the RfD.[FN4: See, Tellez et al., 2005; Amitai et al., 2007; Lewis E. Braverman et al., 

The Effect of Perchlorate, Thiocyanate, and Nitrate on Thyroid Function in Workers Exposed to 

Perchlorate Long-Term, J. Clin. Endocrinol. Metab., 2005, at 700.] 

Second, this extensive scientific literature has undergone several major peer reviews. EPA convened 

peer review panels of its draft risk assessments in 1999 and 2002. The University of Nebraska 

Medical Center convened a State-of-the- Science Symposium and peer review in 2003. From 

October 2004 to January 2005, the NRC panel of 15 national experts held several meetings and 

solicited extensive public comment. While the SAB can contribute to the findings of these panels, 

EPA already has extensive, independent scientific analysis of perchlorate to underpin its final 

determination. 

Response: Administrator Stephen Johnson replied to the SAB on January 9, 2009. The letter is 

available in EPA’s docket ID No. EPA-HQ-OW-2009-0297 for this notice. 

Commenter Name: John C. Vest 

Commenter Organization: Public Service Department, Town of Mooresville, NC 

EPA Document ID: EPA-HQ-OW-2008-0692-1567 
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EPA Comment ID: 20667 

EPA Comment Code: 6110 

 

Comment: John C. Vest, P.E. Public Services Director PO Box 878 Mooresville, NC 28115 (704) 

790-4290 

 November 7, 2008 

 Water Docket Environmental Protection Agency 1200 Pennsylvania Avenue, NW Washington, DC 

RE: Docket ID No. EPA-HQ-OW-2008-0068 Drinking Water: Preliminary Regulatory 

Determination on Perchlorate 

The Public Services Department of the Town of Mooresville, North Carolina agrees with the 

Environmental Protection Agency's determination that a national primary drinking water regulation 

(NPDWR) for perchlorate would not present a meaningful opportunity for health risk reduction for 

persons served by public water systems. 

Our determination is based on several factors including research studies submitted by the EPA, 

NAS/NRC and FDA as well as articles released by accredited organizations. Authorities concur 

exposure to perchlorate is not limited to public water sources but is also found in food products. 

Public water sources found with maximum levels of perchlorate affect a small population of the 

country and would be better managed at a local level. The results of testing by a third party 

laboratory in 2002 showed no significant level of perchlorate in the Town of Mooresville's drinking 

water supply. All test results were below the detection limit of 4u/l. 

Should you have any questions, please do not hesitate to contact us. 

Sincerely, 

John C. Vest, P.E. Public Services Director 

Response: EPA believes that regulating perchlorate in drinking water presents a meaningful 

opportunity for health risk reduction. EPA believes that regulating perchlorate in drinking water 

presents a meaningful opportunity for health risk reduction. This determination is based on the best 

available peer reviewed science and data collected in accordance with accepted methods related to 

perchlorate’s occurrence in drinking water , the presence of perchlorate in foods and the potential 

health effects of exposure to perchlorate, and EPA’s population exposure evaluation as described in 

more detail in the final regulatory determination. 

Specifically, The Agency analyzed occurrence data from the Unregulated Contaminant Monitoring 

Rule (UCMR), which is nationally representative, and found that perchlorate occurred in 26 states 

and 2 territories affecting millions of people. EPA agrees that perchlorate contamination is 

widespread in foods; however, EPA does not believe that the widespread presence of perchlorate in 

food overrides the opportunity for public health risk reduction for persons served by PWSs with 

perchlorate contamination. 

Commenter Name: Anonymous 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Document ID: EPA-HQ-OW-2008-0692-1851 

EPA Comment ID: 20740 

EPA Comment Code: 6110 

 

Comment: We are over-regulating ourselves to death! The drinking water is safe enough - there's no 

need to keep upping the bar. This hits people in the pocket book for no good reason. 

Response: Please see the response to comment code 6110. 

Commenter Name: 

Commenter Organization: Ag Council et al 

EPA Document ID: EPA-HQ-OW-2008-0692-1987 

EPA Comment ID: 20974 

EPA Comment Code: 6110 

 

Comment: November 26, 2008 

US Environmental Protection Agency Office of Water Docket (Mailcode 2822T) 1200 Pennsylvania 

Avenue, NW Washington, DC 20460 

RE: Docket ID No. EPA-HQ-OW-2008-0692. Comments on US EPA Preliminary Regulatory 

Determination on Perchlorate. 

The undersigned representatives of the California agricultural industry are pleased to submit the 

following comments regarding US EPA's preliminary regulatory determination on perchlorate. 

California agriculture is a diverse and important sector of our economy. It is a $37 billion industry 

that produces over 350 different crop and livestock commodities and generates an estimated $100 

billion in related economic activity. California agriculture accounts for approximately 7.5% of all 

employment and supports over a million on farm jobs. California agriculture is also the leading 

exporter of agricultural commodities, sending almost 20% of our agricultural production to foreign 

markets. 

Based upon the available scientific studies as well as the available exposure and occurrence data, the 

undersigned support EPA's decision not to establish a national primary drinking water regulation for 

perchlorate. Both the US Food and Drug Administration's (FDA) food sampling data and total 

dietary survey, along with EPA's calculated relative source contribution reveal that total perchlorate 

exposure in the US population is well below established levels of human health concern, even for 

sensitive subpopulations. 

Response: Please see response to comment code 6110. The Agency presented an extensive 

evaluation of dietary exposure to perchlorate in the October 2008 and August 2009 Federal Register 

notices. EPA has used this dietary exposure data to account for the relative source contribution 

(RSC) of perchlorate from food and derived potential alternative HRLs for 14 life stages using the 

RfD and life stage-specific exposure information in the August 9, 2009 Federal Register notice. 

These levels range from 1 ug/L to 47 ug/L. EPA also evaluated the populations exposed to 

perchlorate from both food and drinking water in the August 2009 Federal Register notice and the 

final regulatory determination. EPA recognizes that a drinking water regulation would not eliminate 

perchlorate exposure in drinking water but believes that the reduction in perchlorate exposure 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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presents a meaningful opportunity for health risk reduction for persons served by PWSs 

contaminated by perchlorate. 

. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21052 

EPA Comment Code: 6110 

 

Comment: November 26, 2008 

Docket ID No. EPA-HQ-OW-2008-0692 Water Docket U.S. Environmental Protection Agency 

Mailcode: 2822T 1200 Pennsylvania Ave., NW Washington, DC 20460 

RE: Comments in Response to the EPA Notice, Drinking Water: Preliminary Regulatory 

Determination on Perchlorate [EPA-HQ-OW-2008-0068; FRL-8727-6] RIN 2040-ZA02 

Dear Sir or Madam: 

The Perchlorate Study Group (PSG) is pleased to submit comments in response to the abovecaptioned EPA regulatory proceeding. 

Please note that there are two sets of comments. 

1. Perchlorate and Human Health in 2008: The Implications of New Science for the EPA 

Preliminary Determination. The most important issues for consideration by the Agency relate to the 

state of the science. The unswerving focus of the PSG has been to analyze and make available the 

best available scientific information. The scientific comments were prepared by Intertox, a highlyrespected firm with extensive experience in the scientific considerations relating to perchlorate. 

The Intertox report concludes that the scientific evidence supports the Agency's decision not to 

establish a national primary drinking water standard for perchlorate, because "there is no meaningful 

opportunity for health risk reduction." 

The most important source of scientific information on the human health issues relating to 

perchlorate is an extensive report undertaken by the National Academies of Science, released in 

2005. The NAS report has been relied upon by the EPA in subsequent regulatory actions. 

The Intertox scientific comments bring the scientific information up to date, examining studies 

published after the NAS report. The Intertox study, like the NAS study, does not recommend a level 

for EPA's possible adoption. The Intertox report finds that even with highly conservative 

assumptions, there would be "no significant health risk to the most sensitive individuals" at a level of 

at or below 15 parts per billion. 

Response: Please see the response to comment code 6110. 

Commenter Name: Michael Girard 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 541 of 1099

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21054 

EPA Comment Code: 6110 

 

Comment: PERCHLORATE AND HUMAN HEALTH IN 2008: THE IMPLICATIONS OF 

NEW SCIENCE FOR THE EPA PRELIMINARY DETERMINATION COMMENTS IN 

RESPONSE TO THE EPA NOTICE DRINKING WATER: PRELIMINARY REGULATORY 

DETERMINATION ON PERCHLORATE [EPA-HQ-OW-2008-0068; FRL-8727-6] RIN 2040-

ZA02 

FINAL 

Prepared for: PERCHLORATE STUDY GROUP 

November 25, 2008 

Intertox, Inc. 600 Stewart St. Suite 1101 Seattle, WA 98101 

206.443.2115 phone 206.443.2117 facsimile 

TABLE OF CONTENTS I. INTRODUCTION...............................................................1 II. KEY 

SCIENTIFIC STUDIES PUBLISHED SINCE 2005...............................6 A. ENVIRONMENTAL 

STUDIES......................................................6 B. OCCUPATIONAL OR CLINICAL 

STUDIES..........................................12 C. BREAST MILK 

STUDIES.......................................................13 III. IODINE SUFFICIENCY IN THE UNITED 

STATES.................................18 IV. CONCLUSIONS..............................................................20 IV. 

REFERENCES...............................................................21 

LIST OF APPENDICES 

APPENDIX A. REVIEW OF BLOUNT ET AL., 2006 

LIST OF FIGURES FIGURE 1. URINARY REANALYSIS RESULTS OF THE NHANES 

DATA......................10 FIGURE 2. PLOTTING OF DATA REPORTED BY DASGUPTA ET 

AL., 2008 TO ILLUSTRATE THE ASSOCIATION BETWEEN CONCENTRATIONS OF 

IODINE AND PERCHLORATE IN URINE AND MILK IN LACTATING 

WOMEN...........................................................15 

I. INTRODUCTION 

The Environmental Protection Agency (EPA) has released its preliminary regulatory determination 

on perchlorate for public comment. The EPA is required by the Safe Drinking Water Act (SDWA) 

to publish Maximum Contaminant Level Goals (MCLG) and national primary drinking water 

regulations (NPDWR) IF (emphasis added), 

(a) the contaminant may have an adverse effect on the health of persons; (b) the contaminant is 

known to occur in public water systems with a frequency and at levels of public health concern; and 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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(c) in the sole judgment of the Administrator, regulation of such contaminant presents a meaningful 

opportunity for health risk reduction for persons served by public water systems (73 FR 60264). 

Based on these criteria, the EPA has presented their rationale in the determination not to set an 

NPDWR for perchlorate as it would not present "a meaningful opportunity for health risk reduction 

for persons served by public water systems." This decision was made based on the derivation of a 

Health Reference Level (HRL) for perchlorate and was calculated to be 15 ppb based on a relative 

source contribution (RSC) of 62% (73 FR 60276).. 

Even a cursory review of the 50 years of perchlorate research shows that the weight of scientific 

evidence clearly supports EPA's decision. 

The purpose of this document is to review the key scientific studies and how these studies support 

the EPA's findings in the proposed determination. We present a brief review of the National 

Research Council of the National Academy of Sciences (NRC) assessment and update key studies 

that have been added to the scientific literature. 

Between 1997 and 2002, at least 13 toxicological studies of perchlorate, all using EPA protocols, 

were conducted in animals; these include pharmacokinetic studies, subchronic studies, 

developmental studies, immunotoxicology studies, and a multigenerational reproductive study. All 

studies were conducted over a range of doses and evaluated independently by EPA. Of the many 

results obtained from this work, the most sensitive target organ was the thyroid gland and its 

influence on the body. Studies of potential mutagenic effects were conducted but no such effects 

were found (U.S. EPA, 2002). During the same time period, there were several clinical exposure 

studies in humans and a number of epidemiologic and ecological studies, some in occupational 

settings and some in populations exposed to perchlorate via the community drinking-water supply. 

[Text Box: The body of science supports the Agency's decision not to establish a national primary 

drinking water standard as there is no meaningful opportunity for health risk reduction.] 

Response: Please see the response to comment code 6110. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21079 

EPA Comment Code: 6110 

 

Comment: IV. CONCLUSIONS 

The results of this assessment demonstrate that the RfD continues to be a conservative and healthprotective toxicity guideline value. As such, perchlorate concentrations in drinking water at or below 

the HRL proposed by EPA pose no significant health risk to the most sensitive individuals 

consuming water on a daily basis over a lifetime. Since the release of the RfD, additional studies 

have been conducted and continue to add to the scientific weight of evidence supporting the RfD 

(and HRL) as conservative estimates. The RfD and HRL include uncertainty spanning perhaps an 

order of magnitude, and estimate a daily oral exposure to the human population (including sensitive 

subgroups) that is likely to be without an appreciable risk of deleterious effects during a lifetime. The 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA has further determined that perchlorate is not found in public water supplies at a frequency 

and a level that would cause public health concern. Based on this, the EPA has determined that 

there is not "a meaningful opportunity for health risk reduction for persons served by public water 

systems" by determining a NPDWR. 

IV. REFERENCES 

Amitai Y, Winston G, Sack J, Wasser J, Lewis M, Blount BC, Valentin-Blasini L, Fisher N, Israeli A, 

Leventhal A. 2007. Gestational exposure to high perchlorate concentrations in drinking waer and 

neonatal thyroxine levels. Thyroid 17:843-850. 

Agency for Toxic Substances and Disease Registry (ATSDR). 2008. Toxicological Profiles for 

Perchlorate. American Thyroid Association (ATA). 2006. Update on the Question of Perchlorate 

Exposure and Potential Effects on the Thyroid: Response to CDC Report of Environmental 

Perchlorate Exposure. Accessed at 

http://www.thyroid.org/professionals/publications/statements/06_12_13_perchlorat e.html. 

American Water Works Association, 2008). National Cost Implications of a Potential Perchlorate 

Regulation, Jul. 2008, at 31). 

Barr DB, Wilder LC, Caudill SP, Gonzalez AJ, Needham LL, and Pirkle JL. 2005. Urinary creatinine 

concentrations in the U.S. population: implications for urinary biologic monitoring measurements. 

Environ. Health Perspect. 113 (2):192-200. 

Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell KL. 2006. Urinary perchlorate and 

thyroid hormone levels in adolescent and adult men and women living in the United States. Environ 

Health Perspect. 114(12):1865-71. 

Blount BC, Valentin-Blasini L, Osterloh JD, Mauldin JP, Pirkle JL. 2007. Perchlorate exposure of 

the US population, 2001-2002. J Expo Sci Environ Epidemiol. 17(4):400-7. 

Braverman LE, He X, Pino S, Cross M, Magnani B, Lamm SH, Kruse MB, Engel A, Crump KS, 

Gibbs JP. 2005. The effect of perchlorate, thiocyanate, and nitrate on thyroid function in workers 

exposed to perchlorate long-term. J Clin Endocrinol Metab 90:700-706. 

Braverman LE, Pearce EN, He X, Pino S, Seeley M, Beck B, Magnani B, Blount BC, Firek A. 2006. 

Effects of six months of daily low-dose perchlorate exposure on thyroid function in healthy 

volunteers. J Clin Endocrinol Metab. 91(7):2721-4. Epub 2006 Apr 24. 

Borak J. 2005. Adequacy of iodine nutrition in the United States. Conn Med 69:73-77. 

CDC 2006. National Health and Nutrition Examination Survey (NHANES). Centers for Disease 

Control and Prevention. Accessed October 20, 2006. 

Clewell RA, Merrill EA, Gearhart JM, Robinson PJ, Sterner TR, Mattie DR, Clewell HJ 3rd. 2007. 

Perchlorate and radioiodide kinetics across life stages in the human: using PBPK models to predict 

dosimetry and thyroid inhibition and sensitive subpopulations based on developmental stage. J 

Toxicol Environ Health A 70:408-28. 
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Crawford-Brown D, Raucher B, Harrod M. 2006. Intersubject variability of risk from perchlorate in 

community water supplies. Environ Health Perspect 114:975-979. 

Dasgupta PK, Martinelangd PK, Jackson WA, Anderson TA, Kang T, TDCK RW, Rajagopalan S. 

2005. The Role of Naturally Occurring Perchlorate: The Role of Atmospheric Processes. Environ 

Sci Technol 39:1569-1575. 

Dasgupta PK, Dyke JV, Kirk AB, Jackson WA. 2006. Perchlorate in the United States. Analysis of 

Relative Source Contributions to the Food Chain Environ Sci Technol 40:6608-6614. 

Das Gupta PK, Kirk AB, Dyke JV, Ohira S. 2008. Intake of iodine and perchlorate and excretion in 

human milk. Environ. Sci, Technol. 

Dohan O, Portulano C, Basquin C, Reyna-Neyra A, Amzel LM, Carrasco N. 2007. The Na+/I 

symporter (NIS) mediates electroneutral active transport of the environmental pollutant perchlorate. 

PNAS 104(51):20250-5. 

Furnee CA, van der Haar F, West CE, and Hautvast JG. 1994. A critical appraisal of goiter 

assessment and the ratio of urinary iodine to creatinine for evaluating iodine status. Am J Clin 

Nutr.59 (6):1415-7. 

Gibbs JP, Van Landingham C. 2008. Urinary perchlorate excretion does not predict thyroid function 

among pregnant women. Thyroid 18:807-808. 

Ginsberg G, Rice D. 2005. The NAS Perchlorate Review: Ginsberg et al. Respond. Environ Health 

Perspect. 113:A730-A732. 

Greer MA, Goodman G, Pleus RC, Greer SE. 2002. Health effects assessment for environmental 

perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake in 

humans. Environ Health Perspect. 110(9):927-37. Erratum in: Environ Health Perspect. 2005 

Nov;113(11):A732. 

Kirk AB, Martinelango PK, Tian K, Dutta A, Smith EE, Dasgupta PK. 2005. Perchlorate and iodide 

in dairy and breast milk. Environ Sci Technol. 39(7):2011-7. 

Lamm SH, Hollowell JG, Engel A, Chen R 2008 Perchlorate, thiocyanate, and low iodine 

association not seen with low creatinine-adjusted urine iodine among women of childbearing age 

[abstract]. Thyroid. 17 Suppl (S51). 

Merrill EA, Clewell RA, Robinson PJ, Jarabek AM, Gearhart JM, Sterner TR, Fisher JW. 2005. 

PBPK Model for Radioactive Iodide and Perchlorate Kinetics and Perchlorate-Induced Inhibition of 

Iodide Uptake in Humans, Toxicological Sciences 83:25-43. 

Murray CW, Egan SK, Kim H, Beru N, Bolger PM. 2008. US Food and Drug Administration's 

Total Diet Study: Dietary intake of perchlorate and iodine. J Expo Sci Environ Epidemiol. Jan 2, 

2008. [Epub ahead of print] 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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National Research Council of the National Academies (NRC). 2005. Health Implications of 

Perchlorate Ingestion. Committee to Assess the Health Implications of Perchlorate Ingestion, Board 

on Environmental Studies and Toxicology, Division on Earth and Life Studies. Washington, D.C.: 

The National Academies Press. 

Pearce EN, Lazarus JH, Smythe PP, et al. 2007a. Thyroid function is not affected by environmental 

perchlorate exposure in first trimester pregnant women. Thyroid. 17 Suppl:S133-134. 

Pearce EN, Leung AM, Blount BC, Bazrafshan HR, He X, Pino S, Valentin-Blasini L, Steinmaus C, 

Miller MD, Howd R. 2007. Impact of smoking and thiocyanate on perchlorate and thyroid hormone 

associations in the 2001-2002 national health and nutrition examination survey. Environ Health 

Perspect. 115(9):1333-8. 

Rajagopalan S, Anderson TA, Fahlquist L, Rainwater KA, Ridley M, Jackson WA. 2006. Widespread 

Presence of Naturally Occurring Perchlorate in High Plains of Texas and New Mexico. Environ Sci 

Technol 40:3156-3162. 

Strategic Environmental Research and Development Program (SERDP). 2005. Alternative Causes 

of Widespread, Low-Level Perchlorate Impacts to Groundwater. 

Tellez RT, Chacon PM, Abarca CR, Blount BC, Van Landingham CB, Crump KS, Gibbs JP. 2005. 

Longterm environmental exposure to perchlorate through drinking water and thyroid function 

during pregnancy and the neonatal period. Thyroid. 15(9):963-975. 

Tonacchera M, Pinchera A, Dimida A, Ferrarini E, Agretti P, Vitti P, Santini F, Crump K, and 

Gibbs J. 2004. Relative potencies and additivity of perchlorate, thiocyanate, nitrate, and iodide on 

the inhibition of radioactive iodide uptake by the human sodium iodide symporter. Thyroid. 14 

(12):1012-9. 

U.S. Environmental Protection Agency (EPA). 1989. Risk Assessment Guidance for Superfund, 

Volume 1, Human Health Evaluation Manual (PartA) (EPA/540/1-89/002). Interim Final. 

Washington, D.C. Office of Emergency and Remedial Response. 

U.S. Environmental Protection Agency (EPA). 1999. Exposures Factor Handbook (EPA/600/C99/001). Washington, D.C.: Office of Research & Development. 

U.S. Environmental Protection Agency (EPA). 1998a. Perchlorate Environmental Contamination: 

Toxicological Review and Risk Characterization Based on Emerging Information, Review Draft 

(NCEA-1-0503). Washington, D.C.: Office of Research and Development. December 31. 

U.S. Environmental Protection Agency (EPA). 2002. Perchlorate Environmental Contamination: 

Toxicological Review and Risk Characterization (NCEA-1-05-3), External Review Draft. 

Washington, D.C.: Office of Research and Development. January 16. 

U.S. Environmental Protection Agency (EPA) Integrated Risk Information System (IRIS). 2005. 

Perchlorate and Perchlorate Salts. Wartenberg D, buckler G. 2001. Invited commentary: Assessing 

latex sensitization using data from NHANES III. Am J Epidem 153. 
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Response: Please see the response to comment code 6110. EPA estimates that at least 5.1 to 16.6 

million people are served by PWSs, for which we have data, that have perchlorate contamination. 

EPA has determined that an NPDWR for perchlorate could reduce exposures for these populations 

to levels below the potential alternative HRLs that EPA has identified as levels of public health 

concern for perchlorate. 

EPA believes that this perchlorate exposure reduction presents a meaningful opportunity for the 

reduction of health risks for persons served by PWSs. 

 This determination is based on the best available peer reviewed science and data collected in 

accordance with accepted methods related to perchlorate’s occurrence in drinking water, the 

presence of perchlorate in foods and the potential health effects of exposure to perchlorate, and 

EPA’s population exposure evaluation as described in more detail in the final regulatory 

determination. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21089 

EPA Comment Code: 6110 

 

Comment: US Environmental Protection Agency Office of Water Docket (Mailcode 2822T) 1200 

Pennsylvania Avenue, NW Washington, DC 20460 

November 10, 2008 

Re: Comments in Response to EPA Notice Drinking Water: Preliminary Regulatory Determination 

on Perchlorate [EPA-HQ-OW-2008-0692; FRL-8727-6]. 

The Perchlorate Study Group (PSG) is pleased to submit comments to the Environmental 

Protection Agency (EPA) on Docket ID No. EPA-HQ-OW-2008-0692, entitled Drinking Water: 

Preliminary Regulatory Determination on Perchlorate. As manufacturers and users of perchlorate, 

the PSG is committed to ensuring that the best available science is provided in public debate and 

applied in the subsequent setting of regulatory standards. The member companies of the PSG 

include Aerojet, American Pacific Corporation (AMPAC), Alliant Techsystems (ATK), and Tronox. 

For over ten years, the PSG has worked cooperatively and effectively with the US Environmental 

Protection Agency (EPA) and other federal agencies, state governments, and water purveyors to: 

* increase scientific and medical understanding of perchlorate's possible effects on human health; 

and, 

* assess the level of perchlorate in drinking water that is expected to pose no adverse effects to 

human health. 

We therefore appreciate this opportunity to submit these comments relating to EPA's preliminary 

determination. 

I. The EPA's Proposed Determination is Backed by the Best Science and the Statute 
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The PSG agrees with EPA's preliminary determination that a Federal drinking water regulation 

would not meet the SDWA criteria and that EPA has ample justification for this determination. 

EPA has an extraordinary wealth of comprehensive, authoritative scientific information relating to 

perchlorate's health effects, supplemented by extensive occurrence and exposure data. The Agency is 

therefore exceptionally well-positioned to issue a well-considered regulatory determination. The best 

available scientific data supports a determination under the Safe Drinking Water Act (SDWA) that 

public water systems do not present a meaningful opportunity for risk reduction. 

Response: Please see the response to comment code 6110. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21092 

EPA Comment Code: 6110 

 

Comment: Second, EPA has ample scientific and technical data to make a final determination on or 

before the planned date of December 2008. As noted in the attached scientific summary, perchlorate 

is one of the most well-studied chemicals with detailed information on the mechanism of action, 

dose-response, and health effects. This issue also is not new. EPA released its first draft risk 

assessment on perchlorate in 1998, followed by a second in 2002. The 2005 NAS report was a 

comprehensive review of the science. The animal and human studies that have been published since 

the NAS report reduce the uncertainty and reinforce the NAS panel's finding that there will not be 

any adverse health effects from perchlorate at environmentally-relevant concentrations. 

New studies published since the NAS report increase the weight of evidence that the current RfD 

protects human health including the most sensitive members of our population. In addition, 

testimony by Congressional members and witnesses alike have discussed the lengthy amount of time 

that EPA has spent studying the health effects, urging the agency to issue a determination as soon as 

practicable. We join them in urging EPA to issue the final determination promptly. 

Response: Please see the response to comment code 6110. 

Commenter Name: Ed Thomas 

Commenter Organization: National Rural Water Association (NRWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0521 

EPA Comment ID: 28474 

EPA Comment Code: 6110 

 

Comment: Please accept the attached comments. Thank-you ED THOMAS 

Attachment 

 September 18, 2009 

U.S. Environmental Protection Agency Office of Water Docket (Mailcode 2822T) 1200 

Pennsylvania Ave. NW Washington, DC 20460 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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RE: Drinking Water: Perchlorate Supplemental Request for Comments (Docket Number: EPA-HQOW-2009-0297) 

To Whom It May Concern: 

NRWA commends EPA for their proposed regulatory determination for perchlorate. We believe the 

Agency has relied on sound science and that a national standard for perchlorate would not result in a 

meaningful opportunity for health risk reduction. 

Response: Please see the response to comment code 6110. 

Commenter Name: Mark S. Mayer 

Commenter Organization: South Dakota Department of Environment & Natural Resources 

(DENR) 

EPA Document ID: EPA-HQ-OW-2009-0297-0467 

EPA Comment ID: 28478 

EPA Comment Code: 6110 

 

Comment: September 18, 2009 

Comment Clerk Docket EPA-HQ-OW-2009-0297 U.S. Environmental Protection Agency Mail 

Code: 2822T 1200 Pennsylvania Avenue, NW Washington, DC 20460 

To Whom It May Concern: 

Thank you for the opportunity to provide comment on the Perchlorate Supplemental Request as 

published in the August 19, 2009 (Volume 74, Number 159) Federal Register. We have reviewed the 

request and offer the comments found in the attachment. 

We hope EPA will favorably consider our comments. Thank you again. 

Sincerely, Mark S. Mayer, P.E. Natural Resources Administrator SD Drinking Water Program 

cc: Jim Taft, Executive Director, Association of Safe Drinking Water Administrators Carol Rushin, 

Acting EPA Region 8 Administrator Jason Glodt, Senior Policy Advisor, Governor's Office James, 

Stone, Chair South Dakota Section of the American Water Works Association 

 Attachment 

Perchlorate Supplemental Request Comments by South Dakota Department of Environment and 

Natural Resources (DENR) 

General Comments: 

- The South Dakota Department of Environment and Natural Resources (DENR) supports EPA's 

preliminary decision to not regulate Perchlorate, and finds no reason now to alter that decision. 

Based on the information obtained from the contaminant candidate list and Unregulated 
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Contaminant Monitoring processes used by EPA to obtain occurrence data on unregulated 

contaminates, Perchlorate is not a drinking water issue in South Dakota. Consequently, South 

Dakota does not support EPA establishing a new national regulation for Perchlorate. Such a new 

rule will become another regulatory burden for our drinking water systems, but it would have no 

positive health effects or benefits for their customers. 

Response: Please see the response to comment code 6110. 

Commenter Name: Julie L. Heckman 

Commenter Organization: American Pyrotechnics Association (APA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0522 

EPA Comment ID: 28490 

EPA Comment Code: 6110 

 

Comment: The premature or excessive regulation of perchlorate absent full consideration of all the 

facts and all the science, particularly for so new a concern, would threaten the fireworks industry's 

ability to continue to serve the country. It would threaten the nation's ability to continue to respect 

the most patriotic of its traditions. 

Response: Please see the response to comment code 6110. Today’s determination is based upon an 

assessment of the best available science and information. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0653 

EPA Comment ID: 28556 

EPA Comment Code: 6110 

 

Comment: The PBPK modeling is useful in demonstrating that all identified lifestages are protected 

at the RfD level, and especially under the current HAL of 15 ppb perchlorate in drinking water as 

they are within the 10x intraspecies factor. The alternative methods of exposure assessment are 

informative but do not show that any deviation from EPA's typical risk assessment based on a 70 kg 

adult consuming two liters of water is warranted. As the occurrence of perchlorate in water supplies 

is sporadic and geographically discreet, the Agency has not provided sufficient information or 

explanation to justify using Bayesian analyses of water occurrence data. EPA has sufficient 

information to determine that perchlorate should not be regulated as a drinking water contaminant 

under the Safe Drinking Water Act and should maintain a recommended health advisory limit of 15 

ppb. 

Response: Please see the response to comment code 6110. After further consideration of the peer 

review and public comments, EPA concludes that the PBPK modeling analysis, in the context of the 

perchlorate regulatory determination, is useful in examining which life stages are most susceptible to 

the effects of perchlorate. For example, the model indicates that a fetus may be seven times more 

sensitive to the effects of perchlorate than a pregnant woman. The model also allows for the 

estimation of the concentration of perchlorate in breast milk (thus breast-fed infant exposure) at 

various maternal perchlorate exposure levels. However, because of the stated limitations, EPA has 

decided the model does not directly bear on the current decision regarding the need for a NPDWR 
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for perchlorate. EPA is continuing to evaluate whether the model could be used in setting a 

NPDWR for perchlorate. 

EPA believes that perchlorate contamination in drinking water does not occur sporadically. The 

Agency analyzed occurrence data from the Unregulated Contaminant Monitoring Rule (UCMR), 

which is nationally representative, and found that perchlorate occurred in 26 states and 2 territories. 

EPA continues to evaluate the utility of the Bayesian model(s) in the development of a NPDWR for 

perchlorate. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0653 

EPA Comment ID: 28557 

EPA Comment Code: 6110 

 

Comment: Attachment 

The Environmental Protection Agency (EPA) has sufficient information to make a regulatory 

determination concerning perchlorate under the Safe Drinking Water Act (SDWA) - perchlorate 

does not meet the three criteria necessary for regulation - therefore, the Administrator can determine 

that the EPA should maintain its guidance for a Health Advisory Limit (HAL) at 15 parts per billion 

(ppb) in drinking water and can decide not to regulate perchlorate under the SDWA. The Agency 

continues to waste public resources and time based on ill- informed critiques of the National 

Research Council (NRC) 2005 findings on perchlorate. 

Response: Please see response to comment code 6110. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0653 

EPA Comment ID: 28562 

EPA Comment Code: 6110 

 

Comment: In summary, the PBPK modeling is useful in demonstrating that all identified lifestages 

are protected at the RfD level, and especially under the current HAL of 15 ppb perchlorate in 

drinking water as they are within the 10x intraspecies factor in terms of potential risk. The 

alternative methods of exposure assessment are informative but do not show that any deviation 

from EPA’s typical risk assessment based on a 70 kg adult consuming two liters of water is 

warranted. As the occurrence of perchlorate in water supplies is sporadic and geographically 

discreet, the Agency has not provided sufficient information or explanation to justify using Bayesian 

analyses of water occurrence data. EPA has sufficient information to determine that perchlorate 

should not be regulated as a drinking water contaminant under the Safe Drinking Water Act and 

should maintain a recommended health advisory limit of 15 ppb. 

Response: Please see response to comment ID 28556 under comment code 6110. 

Commenter Name: Sonia Salas 
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Commenter Organization: Western Growers Association on behalf of several California 

agriculture groups 

EPA Document ID: EPA-HQ-OW-2009-0297-0652 

EPA Comment ID: 28683 

EPA Comment Code: 6110 

 

Comment: Conclusion 

Based upon the best available scientific evidence, including exposure and occurrence data developed 

since the National Academy of Sciences issued its findings in January, 2005, the undersigned 

conclude that the regulatory thresholds contemplated in EPA's above referenced notice are not 

scientifically justified and are substantially more stringent than necessary to ensure protection of 

public health. Moreover, the US Food and Drug Administration's (FDA) food sampling data and 

total dietary survey, and the relative source contribution calculated by USEPA for its 2008 

preliminary regulatory determination demonstrate conclusively that total perchlorate exposure in the 

US population is well below established levels of human health concern for both the general public 

and sensitive subpopulations. 

For the reasons articulated above, the California agricultural industry encourages USEPA to act on 

its October 10, 2008 preliminary regulatory determination for perchlorate, which the weight of 

scientific evidence demonstrates to be highly health protective. We appreciate USEPA's 

consideration of our comments and we remain committed to working with USEPA, USDA and 

FDA to preserve the safety and integrity of our products and their contribution to balanced, healthy 

diets. 

Sincerely, Agricultural Council of California California Citrus Mutual California Cotton Ginners and 

Growers Association California Farm Bureau Federation California Floral Council California Grape 

and Tree Fruit League Grower-Shipper Association of Central California Imperial Valley Vegetable 

Grower Association Ventura County Agricultural Association Nisei Farmers League Ventura 

County Agricultural Association Western Growers Association Western Plant Health Association 

Western United Dairymen 

Response: Please see the response to comment code 6110. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0647 

EPA Comment ID: 28716 

EPA Comment Code: 6110 

 

Comment: Introduction 

These comments are provided in further support of EPA's preliminary determination that 

establishment of a perchlorate drinking water standard is not merited, and in reference to comments 

already posted by Jonathan Borak on September 21st under reference EPA-HQ-OW-2009-0297-

0209.1. Mr. Borak's comments refer primarily to the Blount, et al., 2006 study regarding the 

association of low background levels of perchlorate with thyroid hormone levels. Notwithstanding 

the many inconsistencies and contradictions in this study as noted by Mr. Borak and others, it is 
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clear in reviewing other comments submitted under Docket EPA-HQ-OW-2009-0297, that the 

Blount study is still being heavily relied upon by supporters of perchlorate regulation, who point to 

this study as proof of the effect of low background levels of perchlorate on thyroid function. 

Response: Please see the response to comment code 6110. EPA did consider the data presented in 

the Blount et al., 2006 study as well as other information on perchlorate exposure. EPA will consider 

the best available science and information as EPA develops the perchlorate regulation. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0415 

EPA Comment ID: 28841 

EPA Comment Code: 6110 

 

Comment: Please accept the attached comments on behalf of the American Water Works 

Association. 

Attachment 

 September 18, 2009 

U.S. Environmental Protection Agency Office of Water Docket (Mailcode 2822T) 1200 

Pennsylvania Ave. NW Washington, DC 20460 

 RE: Drinking Water: Perchlorate Supplemental Request for Comments Docket EPA-HQ- OW2009-0297 

The American Water Works Association appreciates the opportunity to comment on the 

supplemental request for comments regarding perchlorate as detailed in the August 3, 2009 Federal 

Register notice (74 FR 41883). AWWA is an international, nonprofit, scientific and educational 

society dedicated to the improvement of drinking water quality and supply. Founded in 1881, the 

Association is the largest organization of water supply professionals in the world. Our 57,000 

members represent the full spectrum of the drinking water community: treatment plant operators 

and managers, environmental advocates, engineers, scientists, academicians, and others who hold a 

genuine interest in water supply and public health. Our membership includes more than 4,700 

utilities that supply roughly 80 percent of the nation's drinking water. Based on this broad 

membership base, these comments should be considered as representative of the drinking water 

community in general. 

These comments represent a restatement of the position submitted to the Agency in response to 

preliminary regulatory determination for perchlorate as detailed in the October 10, 2008 Federal 

Register notice (73 FR 60262). Given the weight of evidence available at that time and AWWA's 

independent assessment of occurrence and exposure we concurred with Agency's preliminary 

determination that regulation of perchlorate would not present "a meaningful opportunity for health 

risk reduction for persons served by public water systems." We continue to support that preliminary 

determination. Response: Please see the response to comment code 6110. 

Commenter Name: Tom Curtis 
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Page 553 of 1099

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0415 

EPA Comment ID: 28857 

EPA Comment Code: 6110 

 

Comment: Conclusion 

AWWA believes that the Agency's originally proposed decision not to regulate perchlorate is 

supported by the criteria established in the SDWA. The primary public health issue - as stated by the 

NRC and others including the Agency's Inspector General [FN22: Wilson, M. 2008. Scientific 

Analysis of Perchlorate. US Environmental Protection Agency, Office of Inspector 

General:Washington DC. Available at http://www.epa.gov/oigearth/reports/2009/20081230-2008-

0010.pdf] - is iodine deficiency. The SDWA is not an effective means or "tool" to manage a public 

health issue dominated by dietary issues. The public's exposure to all sources of goitrogens due to 

extensive contributions from other sources as demonstrated by the FDA food market assessment 

support the findings that regulation of drinking water would not have a meaningful impact on 

changing the nation's level of iodine deficiency. A precautionary approach is not justified by the 

available public health data that provides no indication of epidemic cretinism, goiter, or 

hypothyroidism, even given the loading of other goitrogens that far exceed potential contribution 

from perchlorate from all sources. A risk management approach that seeks to extract 100 percent of 

the risk reduction value from the smallest possible source is not only ineffective, but is a disservice 

to the mission of seeking the greatest protection of public health. The Agency should use the 

findings of this assessment to support a collaborative effort with the Department of Health and 

Human Services and Department of Agriculture to develop outreach materials that communicate 

the importance of proper dietary levels of iodine, specifically targeting sensitive subpopulations. 

Attempts have been made in the past to ensure the public received appropriate iodine levels.[FN23: 

Medicine: Pass the iodized salt, in Time 1949, 19 September. Available at 

http://www.time.com/time/magazine/article/0,9171,800702,00.html] AWWA believes that 

remains a better approach for addressing the problem of iodine deficiency, instead of using the Safe 

Drinking Water Act to address this issue 

AWWA appreciates the opportunity to comment on these important drinking water issues. If you 

have any questions about these comments, please feel to call Kevin Morley or me in our Washington 

Office at 202-628-8303. 

 Sincerely, Tom Curtis Deputy Executive Director-Government Affairs 

cc: Peter Silva, OW Cynthia Doughtery, OGWDW Eric Burneson, OGWDW 

Response: Please see the response to comment code 6110. EPA agrees that promoting iodide 

nutrition is good public health policy that has a role in reducing the adverse effects associated with 

exposure to perchlorate. However, the Agency is required to undertake the development of a 

national primary drinking water regulation if the provisions under section 1412(b)(1) of SDWA are 

satisfied. That is, if the three legislative criteria are met, EPA must undertake the development of a 

NPDWR. EPA has determined that the three criteria are met for perchlorate for the reasons 

outlined in today’s federal register notice. 

Commenter Name: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 554 of 1099

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28875 

EPA Comment Code: 6110 

 

Comment: EPA, based on a scientific assessment of the literature in 2008, concluded that federal 

regulation of perchlorate in drinking water is unwarranted. More than 50 years of scientific research 

and guidelines support the Agency's position. 

I. INTRODUCTION 

On August 19, 2009, the Environmental Protection Agency (EPA) issued a Federal Register (FR) 

notice requesting comments on additional approaches to analyzing data related to EPA's perchlorate 

regulatory determination (the Notice; U.S. EPA, 2009b). The Notice states that "these additional 

comments are sought in an effort to ensure consideration of all the potential options for evaluating 

whether there is a meaningful opportunity for human health risk reduction of perchlorate through a 

national primary drinking water rule." This document responds to EPA's request for comments on 

behalf of the Perchlorate Study Group (PSG).[FN1: The PSG member companies include Aerojet 

General Corporation, American Pacific Corporation, ATK, and Lockheed Martin Corporation.] 

EPA is required by the Safe Drinking Water Act (SDWA) to publish Maximum Contaminant Level 

Goals (MCLGs) and National Primary Drinking Water Regulations (NPDWR) if all the following 

statutory requirements are met: 

(a) the contaminant may have an adverse effect on the health of persons; 

(b) the contaminant is known to occur in public water systems with a frequency and at levels of 

public health concern; and 

(c) in the sole judgment of the Administrator, regulation of such contaminant presents a meaningful 

opportunity for health risk reduction for persons served by public water systems (U.S. EPA, 1996). 

EPA's statutory criteria for setting a standard are unmet in this case. At exposure levels anticipated 

under the drinking water program, the toxicological literature for perchlorate has demonstrated no 

adverse effect on human health. Second, data from EPA's first cycle of the Unregulated 

Contaminant Monitoring Rule (UCMR1) demonstrates that perchlorate does not consistently occur 

in public water systems at levels that may cause adverse effects in humans. Lastly, because the first 

two requirements are not met, there is no meaningful opportunity for health risk reduction, the third 

requirement. 

In 2008, EPA concluded that perchlorate did not meet the SDWA requirements and released its 

preliminary regulatory determination on perchlorate for public comment (U.S. EPA, 2008a). EPA 

decided not to set an NPDWR for perchlorate as it would not present "a meaningful opportunity for 

health risk reduction for persons served by public water systems." This decision was based on a 

Health Reference Level (HRL) for perchlorate in drinking water of 15 ppb, calculated based on an 

assumed relative source contribution (RSC) for drinking water of 62% of the reference dose (RfD) 

(U.S. EPA, 2008a). 
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Data on perchlorate exposure in humans support EPA's preliminary regulatory determination. Any 

chemical at a sufficient dose will cause an adverse effect. Since the inception of EPA's evaluation of 

perchlorate and its interim guidance, no evidence of adverse effects from exposure to perchlorate at 

environmental levels in the U.S. has been presented.[FN2: In 1992, EPA began to address 

"...concerns about the potential human health effects of perchlorate discovered in drinking water..." 

and the EPA Superfund Technical Support Center proposed a "provisional" RfD for perchlorate of 

0.0001 mg/kg-d which translates to a drinking water equivalent level (DWEL) of 4 ppb (Dollarhide, 

1992). In 1995 the provisional RfD was revised by EPA and the National Center for Environmental 

Assessment (NCEA) to a range that translates from a DWEL of 4 to 18 ppb (Dollarhide, 1995). 

EPA released a document detailing the derivation of a revised provisional RfD for perchlorate (U.S. 

EPA, 1998a). In this analysis, EPA focused on potential secondary effects of perchlorate exposure 

in the developing organism. In 1999, EPA issued was what is referred to as the "1999 Interim 

Guidance" (Noonan, 1999). EPA states, "...the Office of Research and Development (ORD) 

recommends that the Agency's risk assessors and risk managers continue to use the standing 

provisional RfD range of 0.0001 to 0.0005 mg/kg-d [4 to 18 ppb equivalent] for perchlorate-related 

assessment activities." At the same time, the EPA's Office of Water added perchlorate to the 

Contaminant Candidate List (CCL) and perchlorate was added to the UCMR (U.S. EPA, 1999). In 

2003, EPA's Assistant Administrator issued a Memorandum stating, "...we are re-affirming this 

guidance with an added suggestion to carefully consider the low end of the provisional 4-18 ppb 

range."] 

50 years of perchlorate toxicological research shows that the scientific weight- of-evidence decidedly 

supports EPA's preliminary regulatory determination on perchlorate. 

A review of the 50 years of perchlorate toxicological research shows that the weight of scientific 

evidence decidedly supports EPA's preliminary regulatory determination on perchlorate. 

Furthermore, EPA requested manufacturers and users to fund specific scientific studies on the 

health effects of perchlorate. As a result, at least 12 animal studies that cover reproductive and 

developmental toxicity, carcinogenicity, endocrine effects, and other specific toxicological endpoints 

were funded and conducted.[FN3: For example, the following animal studies were required by EPA 

to fill data gaps: Argus Research Laboratories, Inc., 1998; Argus Research Laboratories, Inc., 1999; 

Kiel et al., 1998, 1999; Argus Research Laboratories, Inc., 2001; Primedica, 2001; Bekkedahl et al., 

2000; BRT, 2000a, 2000b; Siglin et al., 2000; York et al., 2001a, 2001b.] The results of the studies 

were transmitted directly to EPA for analysis and without review from industry. 

Response: Please see the response to comment code 6110. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28905 

EPA Comment Code: 6110 

 

Comment: In summary, EPA's existing, scientifically based RfD remains a conservative, 

healthprotective toxicity guideline value. Perchlorate concentrations in drinking water at or below 

the 15 ppb HRL set by EPA, along with its existing, preliminary determination, pose no significant 

health risk, even to the most sensitive individuals consuming water on a daily basis over a lifetime. 
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Finally, the best available science establishes that none of the three requirements of the SDWA are 

met; therefore, there is no scientific justification to regulate perchlorate under this statute. 

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Greer MA, Stott AK, Milne KA. 1966. Effects of thiocyanate, perchlorate and other anions on 

thyroidal iodine metabolism. Endocrinology 79:237-247. 

Greer MA, Goodman G, Pleus RC, Greer SE. 2002. Health effects assessment for environmental 

perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake in 

humans. Environ Health Perspect 110(9):927-37. Erratum in: Environ Health Perspect 

113(11):A732. 

Intertox. 2008. Perchlorate and human health in 2008: the implications of new science for the EPA 

preliminary determination, comments in response to the EPA notice drinking water: preliminary 

regulatory determination on perchlorate [EPA- HQ-OW-2008-0068; FRL-8727-6] RIN 2040-ZA02, 

November 25, 2008, Prepared for the Perchlorate Study Group. 

Intertox. 2009. Response to the Environmental Protection Agency Office of Inspector General 

Scientific Analysis of Perchlorate. Accessed at 

http://www.epa.gov/oig/reports/2009/PSG%20Perchlorate%20Comments.pdf. 

Johnston, RB, Corley, R, Cowan, L, Utiger, RD. 2005. The NAS Perchlorate Review: Adverse 

Effects? Environ Health Perspect 113(11): A728-A729. 

Kahn HD, Stralka K. 2008. Estimated daily average per capita water ingestion by child and adult age 

categories based on USDA's 1994-1996 and 1998 continuing survey of food intakes by individuals. 

Journal of Exposure Science & Environmental Epidemiology 19(4):396-404. 

Keil D, Warren A, Jenny M, EuDaly J and Dillard R. 1998. Effects of Ammonium Perchlorate on 

Immunotoxicological, Hematological, and Thyroid Parameters in B6C3F1 Female Mice. Charleston, 

SC. Medical University of South Carolina, Department of Medical Laboratory Sciences. Report no. 

DSWA01-97-0008. September 30. 

Keil D, Warren A, Jenny M, EuDaly J, Dillard R. 1999. Effects of Ammonium Perchlorate on 

Immunotoxicological, Hematological, and Thyroid Parameters in B6C3F1 Female Mice. Charleston, 

SC. Medical University of South Carolina, Department of Medical Laboratory Sciences. Report no. 

DSWA01-97-0008. June 19. 

Kirk AB, Martinelango PK, Tian K, Dutta A, Smith EE, Dasgupta PK. 2005. Perchlorate and iodide 

in dairy and breast milk. Environ Sci Technol 39(7):2011-7. 

Kirk AB, Dyke JV, Martin CF, Dasgupta PK. 2007. Temporal patterns in perchlorate, thiocyanate, 

and iodide excretion in human milk. Environ Health Perspect 115:182-6. 

Klaassen CD. 2001. Casarett & Doull's Toxicology: The basic science of poisons. 6th Edition. 

McGraw-Hill Publishing: New York. 

Lamm SH, Hollowell JG, Engel A, Chen R. 2008. Perchlorate, thiocyanate, and low iodine 

association not seen with low creatinine-adjusted urine iodine among women of childbearing age 

[abstract]. Thyroid 17 Suppl (S51). 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Lawrence JE, Lamm SH, Pino S, Richman K, Braverman LE. 2000. The effect of short-term lowdose perchlorate on various aspects of thyroid function. Thyroid 10:659-63. 

Lawrence J, Lamm S, Braverman LE. 2001. Low dose perchlorate (3 mg daily) and thyroid function. 

Thyroid 11:295. 

Life Sciences Research Office (LSRO), Federation of American Societies for Experimental Biology 

Prepared for the Interagency Board for Nutrition Monitoring and Related Research . 1995. Third 

Report on Nutrition Monitoring in the United States: Volume 1. U.S. Government Printing Office, 

Washington DC. 

Mager, DE, Wyska, E, Jusko WJ. 2003. Minireview: Diversity of mechanism based 

pharmacodynamic models. Drug Metab Dep 31:510-519. 

McLanahan ED, Andersen ME, Campbell Jr. JL, Fisher JW. 2009. Competitive Inhibition of 

Thyroidal Uptake of Dietary Iodide by Perchlorate Does Not Describe Perturbations in Rat Serum 

Total T4 and TSH. Environ Health Perspect 117:731-738. 

Mendez W, Dederick E, Cohen J. 2009. Drinking water contribution to aggregae perchlorate intake 

of reproductive-age women in the United States estimated by dietary intake simulation and analysis 

of urinary excretion data. Journal of Exposure Science and Environmental Epidemiology [Epub 

ahead of print]. 

Merrill EA, Clewell RA, Robinson PJ, Jarabek AM, Gearhart JM, Sterner TR, Fisher JW. 2005. 

PBPK Model for Radioactive Iodide and Perchlorate Kinetics and Perchlorate-Induced Inhibition of 

Iodide Uptake in Humans. Toxicological Sciences 83:25-43. 

Murray CW, Egan SK, Kim H, Beru N, Bolger PM. 2008. US Food and Drug Administration's 

Total Diet Study: Dietary intake of perchlorate and iodine. J Expo Sci Environ Epidemiol 18(6):571-

80. 

National Research Council of the National Academies (NRC). 2005. Health Implications of 

Perchlorate Ingestion. Committee to Assess the Health Implications of Perchlorate Ingestion, Board 

on Environmental Studies and Toxicology, Division on Earth and Life Studies. Washington, D.C.: 

The National Academies Press. 

Noonan NE. 1999. Interim Assessment Guidance for Perchlorate. Memorandum. United States 

Environmental Protection Agency, Office of Research and Development. Washington, DC June 18. 

Accessed at http://www.epa.gov/swerrims/docs/perchlorate/interim_guid_perchlorate_6-99.pdf. 

Norden MM, Larsson F, Tedelind S, Carlsson T, Lundh C, Forssell-Aronsson E, Nilsson M. 2007. 

Down-regulation of the sodium/iodide symporter explains 131I- induced thyroid stunning. Cancer 

Res 67(15):7512-7. 

Pearce EN, Lazarus JH, Smythe PP, et al. 2007a. Thyroid function is not affected by environmental 

perchlorate exposure in first trimester pregnant women. Thyroid 17 Suppl:S133-134. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Pearce EN, Leung AM, Blount BC, Bazrafshan HR, He X, Pino S, Valentin-Blasini L, Braverman 

LE. 2007b. Breast milk iodine and perchlorate concentrations in lactating Boston-area women. J 

Clin Endocr Metab 92(5):1673-7. 

Pedraza PE, Obregon MJ, Escobar-Morreale HF, del Rey FE, de Escobar GM. 2006. Mechanisms 

of adaptation to iodine deficiency in rats: thyroid status is tissue specific. Its relevance for man. 

Endocrinology 147(5):2098-108. 

Primedica. 2001. Hormone, Thyroid and Neurohistological Effects of Oral (Drinking Water) 

Exposure to Ammonium Perchlorate in Pregnant and Lactating Rats and in Fetuses and Nursing 

Pups Exposed to Ammonium Perchlorate during Gestation or via Maternal Milk. (Argus 1416-003). 

Argus Research Laboratories. Horsham, PA. 

Schier JG, Wolkin AF, Valentin-Blasini L, Belson MG, Kieszak SM, Rubin CS, Blount BC. 2009. 

Perchlorate exposure from infant formula and comparisons with the perchlorate reference dose. J 

Expo Sci Environ Epidemiol [Epub ahead of print]. 

Siglin JC, Mattie DR, Dodd DE, Hildebrandt PK and Baker WH. 2000. A 90-day drinking water 

toxicity study in rats of the environmental contaminant ammonium perchlorate. Toxicol Sci 57: 61-

74. 

Smyth PP, Hetherton AM, Smith DF, Radcliff M, O'Herlihy C. 1997. Maternal iodine status and 

thyroid volume during pregnancy: correlation with neonatal iodine intake. JClin Endocrinol Metab 

82(9):2840-3. 

Steinmaus C, Miller MD, Howd R. 2007. Impact of smoking and thiocyanate on perchlorate and 

thyroid hormone associations in the 2001-2002 national health and nutrition examination survey. 

Environ Health Perspect 115(9):1333-8. 

Tellez RT, Chacon PM, Abarca CR, Blount BC, Van Landingham CB, Crump KS, Gibbs JP. 2005. 

Longterm environmental exposure to perchlorate through drinking water and thyroid function 

during pregnancy and the neonatal period. Thyroid 15(9):963-975. 

Tonacchera M, Pinchera A, Dimida A, Ferrarini E, Agretti P, Vitti P, Santini F, Crump K, and 

Gibbs J. 2004. Relative potencies and additivity of perchlorate, thiocyanate, nitrate, and iodide on 

the inhibition of radioactive iodide uptake by the human sodium iodide symporter. Thyroid 14 

(12):1012-9. 

U.S. EPA. 1996. Amendments to the Safe Drinking Water Act, 73 Federal Register 60264. 

U.S. EPA. 1997. Exposures Factor Handbook (EPA/600/C-99/001). Washington, D.C.: Office of 

Research & Development. 

U.S. EPA. 1998a. Perchlorate Environmental Contamination: Toxicological Review and Risk 

Characterization Based on Emerging Information, Review Draft (NCEA-1-0503). Washington, 

D.C.: Office of Research and Development. December 31. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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U.S. EPA. 1998b. National Primary Drinking Water Regulations: Disinfectants and Disinfection 

Byproducts. 63 Federal Register 69404-05. 

U.S. EPA. 1999. Characterization of Perchlorate Contamination - Update August 1999. Page 

ID:1253346. 

U.S. EPA. 2000. Methodology for Deriving Ambient Water Quality Criteria for the Protection of 

Human Health. Office of Water. EPA-822-B-00-004. 

U.S. EPA. 2002. A Review of the reference dose and reference concentration process. Final Report. 

EPA/630/P-02/002F. 

U.S. EPA. 2006. Office of Water: The Analysis of Occurrence Data from the First Unregulated 

Contaminant Monitoring Regulation (UCMR1) in support of Regulatory Determinations for the 

Second Drinking Water Contaminant Candidate List (EPA 815-D-06-008). Accessed at 

http://www.epa.gov/safewater/ccl/pdfs/reg_determine2/report_ccl2- 

reg2_ucmrl_occurrencereport.pdf. 

U.S. EPA. 2008a. Drinking Water: Preliminary Regulatory Determination on Perchlorate, 74 Federal 

Register 8727-6. 

U.S. EPA. 2008b. Office of Inspector General, Scientific Analysis of Perchlorate (External Review 

Draft). United States Environmental Protection Agency, Office of Inspector General. Washington 

D.C. December 30. 

U.S. EPA. 2008d. Child-Specific Exposure Factors Handbook (Final Report). U.S. Environmental 

Protection Agency, Washington, D.C., EPA/600/R-06/096F. 

U.S. EPA. 2009a. Inhibition of the Sodium-Iodide Symporter By Perchlorate: An Evaluation of 

Lifestage Sensitivity Using Physiologically Based Pharmacokinetic (PBPK) Modeling. United States 

Environmental Protection Agency, Office of Research and Development. EPA/600/R-08/106A. 

U.S. EPA. 2009b. Drinking Water: Perchlorate Supplemental Request for Comments, 74 Federal 

Register 41883. 

Wagner S, Aust G, Schott M, Scherbaum WA, Feldkamp J, Seissler J. 2002. Regulation of sodiumiodide-symporter gene expression in human thyrocytes measured by real-time polymerase chain 

reaction. Exp Clin Endocrinol Diabetes 110(8):398-402. 

Wartenberg D, Buckler G. 2001. Invited commentary: Assessing latex sensitization using data from 

NHANES III. Am J Epidem 153. 

WHO. 2004. Vitamin and Mineral Requirements in Human Nutrition. 2nd ed. Geneva: World 

Health Organization and Food and Agriculture Organization (FAO) of the United Nations. 

Wyngaarden JB, Wright BM, Ways P. 1952. The effect of certain anions upon the accumulation and 

retention of iodide by the thyroid gland. Endocrinology 50:537-549. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Wyngaarden JB, Stanbury JB, Rapp B. 1953. The effects of iodide, perchlorate, thiocyanate and 

nitrate administration upon the iodide concentrating mechanism of the rat thyroid. Endocrinology 

52:568-574. 

York RG, Brown WR, Girard MF and Dollarhide JS. 2001a. Oral (drinking water) developmental 

toxicity study of ammonium perchlorate in New Zealand White rabbits. Int J Toxicol 20:199-205. 

York RG, Brown WR, Girard MF and Dollarhide JS. 2001b. Two-generation reproduction study of 

ammonium perchlorate in drinking water in rats evaluates thyroid toxicity. Int J Toxicol 20:183-197. 

Yu KO, Narayanan L, Mattie DR, Godfrey RJ, Todd PN, Sterner TR, Mahle DA, Lumpkin MH, 

Fisher JW. 2002. The pharmacokinetics of perchlorate and its effect on the hypothalamus-pituitarythyroid axis in the male rat. Toxicol Appl Pharmacol 182(2):148-59. 

 APPENDIX A 

SUPPLEMENTAL TABLES 

Table 1. Comparison of body weights from Kahn and Stralka (2008) and NHANES 1996-2000 in 

lbs. [see PDF docket ID EPA-HQ-OW-2009-0297-0662] 

Table 2. Alternative HRLs based on corrected water intake rates. [see PDF docket ID EPA-HQOW-2009-0297-0662] 

Table 3. Comparison of daily water ingestion to blood volume. [see PDF docket ID EPA-HQ-OW2009-0297-0662] 

Response: Please see the response to comment code 6110. EPA continues to support the RfD. 

EPA has determined that perchlorate meets the criteria for regulating a contaminant in Section 

1412(b)(1)(A) of SDWA. As previously discussed in this notice, perchlorate may have an adverse 

effect on the health of persons and perchlorate is known to occur or there is a substantial likelihood 

that perchlorate will occur in public water systems with a frequency and at levels of public health 

concern. Moreover, in light of the discussion in this notice and the information available at this time, 

the Administrator finds that regulation of perchlorate in drinking water systems presents a 

meaningful opportunity for health risk reduction for persons served by public water systems. 

Therefore, EPA will initiate the process of proposing a NPDWR for perchlorate. 

 
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EPA Comment Code: 6120 Comments urging EPA to regulate perchlorate 

Response to Code 6120: EPA has determined that the following three SDWA criteria for 

regulatory determination have been met for perchlorate: (1) It may have an adverse effect on the 

health of persons; (2) It is known to occur or there is a substantial likelihood that perchlorate will 

occur with a frequency and at levels of public health concern in public water systems; and (3) In the 

sole judgment of the Administrator, regulation of perchlorate presents a meaningful opportunity for 

health risk reduction for persons served by public water systems. EPA is initiating the development 

of a proposed NPDWR for perchlorate. EPA intends to publish a proposed regulation and analyses 

required by SDWA for public review and comment within 24 months of this notice. EPA will 

consider the public comments and expects to promulgate a final regulation within 18 months of the 

proposal 

Individual Comments 

Commenter Name: B. Halper 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0080 

EPA Comment ID: 19675 

EPA Comment Code: 6120 

 

Comment: Please regulate the contaminate perchlorate in out drinking water here in AZ to at least 

the same standards as CA has of 6ppb. The truth of the matter is that the standard should be set as 

2 or 3 ppb, but I know this will never happen as long as the DEPT of Defense interferes with this 

matter and scientific data is tampered with. This current deregulation costs our country millions with 

medical problems associated with perchlorate and what this does to our children. 

Response: See response to comment code 6120. 

Commenter Name: Beatrice Williams-Rude 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0083 

EPA Comment ID: 19676 

EPA Comment Code: 6120 

 

Comment: No downgrading drinking water! No! Not from any source or for any claimed reason. 

Beatrice Williams-Rude 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0085 

EPA Comment ID: 19677 

EPA Comment Code: 6120 

 
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Comment: I believe the proposed decision is harmful to public health. Limits on perchlorate should 

not be increased. 

Response: See response to comment code 6120. 

Commenter Name: 

Commenter Organization: Amherst Family Health Center 

EPA Document ID: EPA-HQ-OW-2008-0692-0087 

EPA Comment ID: 19678 

EPA Comment Code: 6120 

 

Comment: this is bad for my patients health. 

Response: This is not a comment, no response needed. 

Commenter Name: D.R. Miller 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0089 

EPA Comment ID: 19679 

EPA Comment Code: 6120 

 

Comment: I strongly oppose perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0090 

EPA Comment ID: 19680 

EPA Comment Code: 6120 

 

Comment: I would like to see the EPA, an organization which my taxes support, regulate any 

chemicals deemed harmful to humans in our drinking water. 

Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0091 

EPA Comment ID: 19681 

EPA Comment Code: 6120 

 

Comment: If you don't protect our drinking water, you don't care about America. Bottom Line. 

Response: This is not a comment, no response necessary. 
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Commenter Name: Nancy Zorn 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0095 

EPA Comment ID: 19682 

EPA Comment Code: 6120 

 

Comment: I am a private citizen protesting the high amount of perchlorate now allowed n drinking 

water. I believe this level is unsafe for pregnant women and young children and should not be 

allowed. I don't belong to any government organization and thought this was a puoblic forum. I am 

a retired public high school teacher. My name is Nancy Zorn and I live at 7121 N. Comanche Ave., 

Warr Acres, OK 73132-6629. 

Response: See response to comment code 6120. 

Commenter Name: Burton Jaffe, MD 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0096 

EPA Comment ID: 19683 

EPA Comment Code: 6120 

 

Comment: As a physician I am very upset that the EPA does not fully protect me, my family, and 

all citizens from perchlorate in tap water. You are the environmental protection agency, and I 

strongly urge you to protect us. Burton Jaffe, MD 

Response: See response to comment code 6120. 

Commenter Name: S Kornbluth 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0099 

EPA Comment ID: 19684 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPA’s refusal to regulate Perchlorate under the 

Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

Please don't wait to regulate Perchlorate. We already know that it has been linked to thyroid 

problems in pregnant women, newborns and young children. Not regulating this harmful chemical 

in our drinking water is unacceptable. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0101 

EPA Comment ID: 19685 

EPA Comment Code: 6120 

 
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Comment: We ordinary citizens rely on our government to keep us safe. Please regulate perchlorate 

in our water. 

Response: See response to comment code 6120. 

Commenter Name: H Moseson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0103 

EPA Comment ID: 19686 

EPA Comment Code: 6120 

 

Comment: Get rid of perchlorate in our water! Current levels are not safe for public health. 

Response: See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #1 - Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0081 

EPA Comment ID: 19687 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPA’s refusal to regulate Perchlorate under the 

Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

Perchlorate is a chemical in rocket fuel that has been linked to thyroid problems in pregnant women, 

newborns and young children. Not regulating this harmful chemical in our drinking water is 

unacceptable. 

Perchlorate is found in drinking water in 35 states, and according to the EPA’s own data, 16 million 

Americans are at risk of being exposed to this dangerous chemical. 

Response: See response to comment code 6120. 

Commenter Name: Mass Mailing #1 - Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0081 

EPA Comment ID: 19687 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPA’s refusal to regulate Perchlorate under the 

Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

Perchlorate is a chemical in rocket fuel that has been linked to thyroid problems in pregnant women, 

newborns and young children. Not regulating this harmful chemical in our drinking water is 

unacceptable. 

Perchlorate is found in drinking water in 35 states, and according to the EPA’s own data, 16 million 

Americans are at risk of being exposed to this dangerous chemical. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Commenter Name: Apparent Mass Mailing #2 - Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0100 

EPA Comment ID: 19689 

EPA Comment Code: 6120 

 

Comment: The Environmental Protection Agency (EPA), supposedly protecting us against harmful 

chemicals in our air, water and food, has formally refused to set a drinking- water standard for 

perchlorate, a chemical in rocket fuel that has been linked to thyroid problems in pregnant women, 

newborns and young children. 

Response: See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #2 - Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0100 

EPA Comment ID: 19689 

EPA Comment Code: 6120 

 

Comment: The Environmental Protection Agency (EPA), supposedly protecting us against harmful 

chemicals in our air, water and food, has formally refused to set a drinking- water standard for 

perchlorate, a chemical in rocket fuel that has been linked to thyroid problems in pregnant women, 

newborns and young children. 

Response: See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #2 - Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0100 

EPA Comment ID: 19691 

EPA Comment Code: 6120 

 

Comment: The Senate Environment and Public Works Committee has endorsed legislation 

requiring the EPA to set a federal standard for perchlorate and to monitor levels of the chemical in 

tap water. 

Please regulate perchlorate in our drinking water: Your current decision is harmful to public health. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0105 

EPA Comment ID: 19692 

EPA Comment Code: 6120 

 

Comment: I would like for the EPA to regulate perchlorate to safe levels for all humans including 

fetuses, babies and children. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Response: See response to comment code 6120. 

Commenter Name: Larry Francis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0107 

EPA Comment ID: 19693 

EPA Comment Code: 6120 

 

Comment: Please take another look at your decision to ignore the chemical perchlorate in our 

drinking water. It seems to me that the patriotic thing to do is protect Americans from dangerous 

chemicals in the environment. Plus, it's your job. Please get to work and set a safe standard for 

perchlorate, certainly not less than the standard set in 2002. 

Hopefully, Larry Francis Applegate, Oregon 

Response: See response to comment code 6120. 

Commenter Name: Ann Watters 

Commenter Organization: Polarity Center of Salem 

EPA Document ID: EPA-HQ-OW-2008-0692-0108 

EPA Comment ID: 19694 

EPA Comment Code: 6120 

 

Comment: This level of Rocket fuel is not suitable for human health... Rocket Fuel should be 

filtered out of the water supply at its source. You are supposed to be protecting the people in this 

country from health hazards.. Do your job please. 

Response: See response to comment code 6120. 

Commenter Name: Alison Dalton 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0111 

EPA Comment ID: 19695 

EPA Comment Code: 6120 

 

Comment: I believe this decision is harmful to public safety. No perchlorate in our drinking water! 

Alison Dalton 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0114 

EPA Comment ID: 19696 

EPA Comment Code: 6120 

 
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Comment: Perchlorate is a chemical in rocket fuel that has been linked to thyroid problems in 

pregnant women, newborns and young children. Not regulating this harmful chemical in our 

drinking water is unacceptable. 

Response: See response to comment code 6120. 

Commenter Name: J.H. Gailey 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0115 

EPA Comment ID: 19697 

EPA Comment Code: 6120 

 

Comment: As a layman with a little background in chemistry the word "perchlorate" scares me, 

especially since we are advising people to restrict their use of such cleaners as Chlorox for home use. 

Perchlorate presents an excess of chlorine to rocket fuel as an oxidizer, but we do not need or want 

that in our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0118 

EPA Comment ID: 19699 

EPA Comment Code: 6120 

 

Comment: Please strongly consider the serious health implications of perchlorate and the risks of 

unregulated perchlorate levels in our drinking water. This issue affects millions of people and should 

not be taken lightly. 

Response: See response to comment code 6120. 

Commenter Name: N Wittenberg 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0120 

EPA Comment ID: 19700 

EPA Comment Code: 6120 

 

Comment: I think this change shows how grossly negligent the EPA has become. Corporations 

have poisoned the EPA and I am personally sick and tired of sitting back and watching it happen!!! 

Response: This is not a comment, no response necessary. 

Commenter Name: Lila Williams 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0121 

EPA Comment ID: 19701 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Comment: I think this decision to allow perchlorate in water is harmful to public health. Please do 

not do it. 

Thank you! 

Lila 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0124 

EPA Comment ID: 19702 

EPA Comment Code: 6120 

 

Comment: If my generation had enough Perchlorate, I don't think my children and grandchildren 

should get more than we had. NO MORE PERCHLORATE! 

Response: See response to comment code 6120. 

Commenter Name: Melissa Mandel 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0125 

EPA Comment ID: 19703 

EPA Comment Code: 6120 

 

Comment: When I recently moved from California to Phoenix Arizona I learned that the local 

water supply is contaminated with Perchlorate. The EPA had the responsibility to prevent such 

contamination at the time it was occurring. Since that did not happen it must protect the public 

health by controlling the legal limit. Raising the limit does not make any sense given the onslaught of 

contaminants assaulting the public from all angles. If anything, it should be lowered (since cleanup is 

not possible). 

Please at least do not raise the legal limit. 

Melissa Mandel 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0127 

EPA Comment ID: 19704 

EPA Comment Code: 6120 

 

Comment: Percholate is not a safe chemical. It is known to cause thyroid problems. Drinking water 

standards for this chemical should be set by the EPA. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 572 of 1099

Response: See response to comment code 6120. 

Commenter Name: B Gagnon 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0128 

EPA Comment ID: 19705 

EPA Comment Code: 6120 

 

Comment: Perchlorate is a dangerous chemical and harmful to women and children. It should 

actually be banned as it is now showing up in milk and lettuce across the nation. 

Not strictly regulating this harmful chemical in our drinking water is totally unacceptable. 

It is clear the the EPA has come under the control of industry. This outrageous decision to allow 

more and more perchlorate contaminants to be considered acceptable in our water is just too much. 

EPA must remember why the taxpayers pay the salaries of those who work there. The American 

people and the future generations must be protected from these kinds of exposures. 

The Safe Water Drinking Act must be honored and EPA must act in good faith on behalf of the 

public. 

You are killing the people. 

Response: See response to comment code 6120. 

Commenter Name: N Mayers 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0129 

EPA Comment ID: 19706 

EPA Comment Code: 6120 

 

Comment: EPA needs to regulate and protect our drinking water from perchlorate, a hazard 

especially to pregnant women. 

Response: See response to comment code 6120. 

Commenter Name: D Burnham 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0182 

EPA Comment ID: 19707 

EPA Comment Code: 6120 

 

Comment: I'm against ANY perchlorate in my water. It NEEDS to be filtered out. It should be 

BELOW the EPA recommendations. 

Response: See response to comment code 6120. 
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Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0185 

EPA Comment ID: 19708 

EPA Comment Code: 6120 

 

Comment: The EPA must set a federal standard for perchlorate and to monitor levels of the 

chemical in tap water. Refusing to do so is harmful to public health. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: T.O. Mellem 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0186 

EPA Comment ID: 19709 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPA's refusal to regulate Perchlorate under the 

Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

Perchlorate has been linked to thyroid problems in pregnant women, newborns and young children. 

Regulation of this chemical in our dringking water is required or it will make the current credit 

crunch look like child's play. Please set a standard for perchlorate that will prevent a health risk for 

million of Americans. I urge you to do so in accordance with the Safe Drinking Water Act. 

Response: See response to comment code 6120. 

Commenter Name: W Fraser 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0187 

EPA Comment ID: 19710 

EPA Comment Code: 6120 

 

Comment: Please make sure to set the acceptable perchlorate limit based on the health of children. 

Response: See response to comment code 6120. 

Commenter Name: S McMillan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0188 

EPA Comment ID: 19711 

EPA Comment Code: 6120 

 

Comment: I am a mother of three who breastfed each of my children. I had my breastmilk tested 

for perchlorate, and sure enough, it was present. Can you imagine what it is like to be a mother 

knowing that you are feeding your precious baby rocket fuel? Think about it... My middle son is 

autisitc. I beat myself up wondering why. What did I do wrong? I tried to be so healthy. Could it be 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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because I fed him perchlorate? This is so wrong. Please do not allow this public health threat to 

continue. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0190 

EPA Comment ID: 19712 

EPA Comment Code: 6120 

 

Comment: PLEASE!!! We have ENOUGH pollutants attacking us from every where, I have a 

GREAT idea, how about setting the limit to ZERO? Do we really NEED the extra chemicals in our 

drinking water, Sometimes I need a little pep, but not JET FUEL!!!! 

Response: See response to comment code 6120. 

Commenter Name: J Garner 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0195 

EPA Comment ID: 19713 

EPA Comment Code: 6120 

 

Comment: when you lower the standard of anything you go further into killing self. this is not an 

advisable thing to do. but since no one in government listens to the people i doubt you will lsiten or 

care one iota to what i a citizen of America thinks. 

Response: See response to comment code 6120. 

Commenter Name: Sally Swithers 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0196 

EPA Comment ID: 19714 

EPA Comment Code: 6120 

 

Comment: You're supposed to PROTECT US! How can you not regulate Perchlorate in our 

water?????????????!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Shame on you. 

Sally Swithers Sarasota, Florida 

Response: See response to comment code 6120. 

Commenter Name: W White 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0132 

EPA Comment ID: 19715 

EPA Comment Code: 6120 

 
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Comment: Please keep perchlorate OUT of our drinking water. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Jon Olsen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0134 

EPA Comment ID: 19716 

EPA Comment Code: 6120 

 

Comment: Regarding the allowance of 15 times the previously allowed (safe amount???) quantity of 

percholate in drinking water sounds to me like a policy of criminal insanity. Both people an our nonhuman life forms need water as close to pure as we can get. Rocket fuel in our drinking water is an 

obscenity. Please think: would you want your baby or grandchild being unwittingly fed such stuff? 

Jon Olsen, Maine 

Response: See response to comment code 6120. 

Commenter Name: David Sparling, M.D., F.A.A.P. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0135 

EPA Comment ID: 19721 

EPA Comment Code: 6120 

 

Comment: In view of the clear evidence that perchlorate ingestion is associated with sjuppression 

of thyroid function, the increased susceptibility of the fetus, infant and young child to that 

suppression, the well known effects of bhypothyroidism on brain development and subsequent adult 

brain function, and the lack of data identifying any threshold level of perchlorate ingestion below 

which thyroid safety in the fetus, infant and young child can be assured, I make two 

recommendations: 

1) Until such data are available, published in peer-reviewed journals and confirmed by subsequent 

studies, there should be no increase in the allowable levels of perchlorate in public drinking water 

supplies, and 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0140 

EPA Comment ID: 19723 

EPA Comment Code: 6120 

 

Comment: I'am a pulmonary and critical care physician in Florida. I want to express my deep 

concern about the EPA's decision on addressing perchlorate in water. This chemical is known to be 

harmful and exposure through water could pose a serious danger to public health. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Response: See response to comment code 6120. 

Commenter Name: Dr Roberta Richardson, MD 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0147 

EPA Comment ID: 19724 

EPA Comment Code: 6120 

 

Comment: This is a comment regarding the EPA's decision not to set a standard for perchlorate in 

drinking water. 

Perchlorate, a component of rocket fuel, has been associated with thyroid disease in pregnant 

women, young children, and newborns. It has been found in the drinking water of over half the 

states. I believe it is necessary for the EPA to set a standard for this compound, for public health 

and safety. I urge you to reconsider your decision. 

Dr. Roberta Richardson, MD 

Response: See response to comment code 6120. 

Commenter Name: Stephen Couche 

Commenter Organization: Community for Earth, First Unitarian Church 

EPA Document ID: EPA-HQ-OW-2008-0692-0149 

EPA Comment ID: 19725 

EPA Comment Code: 6120 

 

Comment: Our Church is in Portland, OR, and although I do not know if Perchlorate is a problem 

anywhere in this state, if it is water systems anywhere it is a problem and health risk. Based on the 

knowledge we have of what the effects of Perchlorate exposure can have on people we feel that 

levels should be kept at the lower level and should not be raised - the health of the people of this 

country is to precious. 

Sincerely, Stephen Couche Community for Earth First Unitarian Church Portland, OR 

Response: See response to comment code 6120. 

Commenter Name: J Mason 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0145 

EPA Comment ID: 19726 

EPA Comment Code: 6120 

 

Comment: Perchlorate is a chemical in rocket fuel that has been linked to thyroid problems in 

pregnant women, newborns and young children. Not regulating this harmful chemical in our 

drinking water is unacceptable. 

Perchlorate is found in drinking water in 35 states, and according to the EPA’s own data, 16 million 

Americans are at risk of being exposed to this dangerous chemical. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Response: See response to comment code 6120. 

Commenter Name: J Mason 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0145 

EPA Comment ID: 19728 

EPA Comment Code: 6120 

 

Comment: My mother and myself are sufferring from thryoid disease.She also has a monoclonal 

gammopathy which doctors say is probably due to environmental exposure: 40+ years of water 

quality deterioration & contamination. My own city says our exposure to carcinogens in our 

"treated" water would affect ONLY those with prolonged exposure of 25 years or more- we 

lived,and drunk this water for 29 years! I am gravely concerned for my children who also have been 

exposed to these contaminents for nearly 20 years. Meanwhile,our pure,natural wells are being 

drained,and exploited by companies who profit; while we, meanwhile, are being poisoned! WHO is 

advocating for us? WHO will STOP this abuse? It is within your power and was mandated BY the 

PEOPLE,FOR the PEOPLE that your agency SERVE OUR INTERESTS AND HEALTHPLEASE DO SO! TIME IS OF THE ESSENCE. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0152 

EPA Comment ID: 19729 

EPA Comment Code: 6120 

 

Comment: Perchlorate standards should not be allowed to risk unsafe levels in human water 

supplies. the weakened standards do pose real risks. The link to thyroid problems is documented 

and EPA failures to protect public health are just not acceptable 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0153 

EPA Comment ID: 19730 

EPA Comment Code: 6120 

 

Comment: This decision is harmful to public health! 

Response: See response to comment code 6120. 

Commenter Name: G McDonald-Tune 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0155 

EPA Comment ID: 19731 
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EPA Comment Code: 6120 

 

Comment: This chemical is dangerous--public health is at stake--it should be carefully monitored 

and regulated 

Response: See response to comment code 6120. 

Commenter Name: William W. Winship 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0157 

EPA Comment ID: 19732 

EPA Comment Code: 6120 

 

Comment: I believe that the refusal to set a drinking-water standard for perchlorate reflects a 

wholesale abandonment of responsibility on the part of the Bush Administration EPA...and is 

blatantly harmful to public health. The Senate Environment and Public Works Committee has 

endorsed legislation requiring the EPA to set a federal standard for perchlorate and to monitor 

levels of the chemical in tap water. Please do so! 

Respectfully, William W. Winship 

Response: See response to comment code 6120. 

Commenter Name: A Roth 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0160 

EPA Comment ID: 19734 

EPA Comment Code: 6120 

 

Comment: I consider the amount of perchlorate in drinking water a danger to public health 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0161 

EPA Comment ID: 19735 

EPA Comment Code: 6120 

 

Comment: I find it irresponsible to remove the regulation of perchlorate in sources or potential 

sources of the drinking water of U.S. residents. Can you demonstrate with data that there is no harm 

to individuals, including children, infants, and pregnant mothers and the fetuses they carry, from 

drinking water containing perchlorate at the levels that you have announced you intend to allow 

(about 15 times higher than the level of perchlorate that the EPA permitted in drinking water in 

2002 )? 

Response: See response to comment code 6120. 
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Commenter Name: Linda Gurley 

Commenter Organization: Gurley Painting 

EPA Document ID: EPA-HQ-OW-2008-0692-0162 

EPA Comment ID: 19736 

EPA Comment Code: 6120 

 

Comment: Docket ID No. EPA-HQ-OW- 2008-0068 

I was a resident of Falmouth, Massachusetts. We had to pay for bottled water as the ground water 

was polluted with fuel from the local Navy airbase. The area around the base is a cancer pocket for 

breast cancer, the cause being directly linked to the ground polution from the jet fuel. Answer the 

questions of the women (if living) and their families, how dangerous ground water pollution from jet 

fuel can effect a population. 

Response: This is not a comment, no response necessary. 

Commenter Name: Wes Sanders 

Commenter Organization: Vermont Interfaith Power & Light 

EPA Document ID: EPA-HQ-OW-2008-0692-0163 

EPA Comment ID: 19737 

EPA Comment Code: 6120 

 

Comment: Raising the "safe" level of perchlorate in drinking water is a palpable danger to the 

public health. 

Response: See response to comment code 6120. 

Commenter Name: J Porter 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0164 

EPA Comment ID: 19738 

EPA Comment Code: 6120 

 

Comment: this decision is harmful to public health! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0166 

EPA Comment ID: 19739 

EPA Comment Code: 6120 

 

Comment: It is past time to make scientific decisions based on science rather than on expediency or 

political pressure. The people of this country do not want perchlorate in their water - your mission 

should be to protect us from this, not to make standards easier for industry or the military. 

Response: This is not a comment, no response necessary. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Commenter Name: Ann Marie Nehme, M.P.H., M.D. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0168 

EPA Comment ID: 19740 

EPA Comment Code: 6120 

 

Comment: I think this is harmful to public health. Ann Marie Nehme, M.P.H., M.D. 

Response: This is not a comment, no response necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0169 

EPA Comment ID: 19741 

EPA Comment Code: 6120 

 

Comment: I think that it is unsafe and a bad decision for the gov not to set a drinking water 

standard for the chemical perchlorate in our tap water. This is outrageous in this day and age, 

especially with all of the technology available in this country to make sure that our water is safe. To 

allow chemicals in our water which have known/unknown bad consequences to our health is a 

travesty and cannot be tolerated. I ask you to reconsider this and make sure our water is free of any 

chemicals which don't belong. There is a reason for the epa..lets not forget what that is. Thank you. 

No, thank me..I pay the taxes that pay you to do your job for me and my neighbors...keeping our 

water safe and chemical free! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0172 

EPA Comment ID: 19742 

EPA Comment Code: 6120 

 

Comment: Thanks, but if its all the same to you, I don't want any perchlorates in my drinking 

water. In fact, I believe it's your responsibility to ensure this; so please, do your job. 

Response: See response to comment code 6120. 

Commenter Name: Cheryl Hall 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0174 

EPA Comment ID: 19743 

EPA Comment Code: 6120 

 

Comment: The current standards for perchlorate in drinking water (with a maximum that is 15 

times higher than what was declared safe in 2002) are unacceptable! This decision does not protect 

our health. 
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Cheryl Hall, citizen 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0280 

EPA Comment ID: 19744 

EPA Comment Code: 6120 

 

Comment: Please keep drinking water safe for my son and our family by not allowing harmful 

chemicals in excess. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0281 

EPA Comment ID: 19745 

EPA Comment Code: 6120 

 

Comment: This was a poor decision, and will prove to be harmful to public health. I hope that this 

is reconsidered. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0282 

EPA Comment ID: 19746 

EPA Comment Code: 6120 

 

Comment: NO Perchlorate!!!! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0289 

EPA Comment ID: 19747 

EPA Comment Code: 6120 

 

Comment: This is a public comment on Docket ID EPA-HQ-OW-2008-0692, Drinking Water: 

Preliminary Regulatory Determination on Perchlorate. 

As a physician experienced in environmental epidemiology, I urge you to regulate perchlorate under 

the Clean Water Act. Perchlorate has been adequately documented as a hazardous chemical with 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 582 of 1099

adverse thyroid effects in pregnant mothers and their offspring. Already an estimated 16 million 

people are exposed to hazardous levels. You must do your job and regulate exposure to this 

chemical. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0290 

EPA Comment ID: 19748 

EPA Comment Code: 6120 

 

Comment: Percholate should be regulated more stringently. It is known to cause thyroid problems 

and it is unconscionable for the EPA to weaken this regulation. Why do you think there is so much 

more cancer than there used to be. Start doing your job and protect the American people not the 

corporations. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0291 

EPA Comment ID: 19749 

EPA Comment Code: 6120 

 

Comment: Please regulate the perchlorate content of our water supply -- It is already 15 times that 

which was the supposedly safe limit several years ago. Not regulating it according to the effect on 

the health of our citizens puts all of us at risk. People are more important than business profits. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0292 

EPA Comment ID: 19750 

EPA Comment Code: 6120 

 

Comment: Please monitor perchlorate! I believe the job of the Environmental Protection Agency is 

PROTECTION, which means monitoring and preventing contaminated drinking water. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Greg Gerritt 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0295 

EPA Comment ID: 19751 

EPA Comment Code: 6120 

 
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Comment: Increasing the amount of perchlorate in water is not a good idea. Do not do this. greg 

gerritt 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0296 

EPA Comment ID: 19752 

EPA Comment Code: 6120 

 

Comment: I believe that allowing more rocket fuel in my drinking water will be harmful to my 

health and the health of my family. 

Perchlorate is a chemical in rocket fuel that has been linked to thyroid problems in pregnant women, 

newborns and young children. 

Response: See response to comment code 6120. 

Commenter Name: Douglas, J. Feldman, PE 

Commenter Organization: Office of Water Resources, Suffolk County Department of Health 

Services (SCDHS) 

EPA Document ID: EPA-HQ-OW-2008-0692-0297 

EPA Comment ID: 19754 

EPA Comment Code: 6120 

 

Comment: This department suggests that perchlorate is sufficiently prevalent on Long Island and in 

other jurisdictions to warrant regulation by establishing a maximum contaminant level. This would 

greatly assist in enforcing remedial action when necessary, as well as to require and encourage 

impacted properties to connect to a public water supply system when feasible. Thank you for the 

opportunity to comment on this subject. 

Douglas J. Feldman, P.E. Principal Public Health Engineer Office of Water Resources SCDHS 360 

Yaphank Ave. Yaphank, NY 11980 Tel (631) 852-5810 Fax (631) 852-5787 

Response: See response to comment code 6120. 

Commenter Name: Barbara Seiple 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0300 

EPA Comment ID: 19755 

EPA Comment Code: 6120 

 

Comment: Please hear us, we the people we need regulation for Perchlorate found in our drinking 

water. We know it can lead to thyroid problems. what is the hold-up 9n getting this regulated? 

Barbara Seiple Philadelphia, PA. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 584 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0302 

EPA Comment ID: 19756 

EPA Comment Code: 6120 

 

Comment: Public drinking water that is safe for human consumption is essential. Given that 

perchlorate has been noted as a causative agent for thyroid disease, especially in pregnant women 

and young children, the EPA must set more stringent standards that will foster risk reduction and 

protect the public health. 

Response: See response to comment code 6120. 

Commenter Name: B Boxer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0233 

EPA Comment ID: 19757 

EPA Comment Code: 6120 

 

Comment: Go back to the stricter standard. Absence of adequate regulation in this area can lead to 

the same type of disaster we are experiencing in the economy. Damage to the health of our people 

and increased costs for health care in future years are likely to be the cost of lax standards. 

Response: See response to comment code 6120. 

Commenter Name: Craig Leman, M.D. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0234 

EPA Comment ID: 19758 

EPA Comment Code: 6120 

 

Comment: Perchlorate is a harmful contaminant, and it is definitely in the national interest to find 

ways to detect and to limit its presence in the environment. Craig Leman. M. D. 

Response: See response to comment code 6120. 

Commenter Name: Trudi Ferguson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0235 

EPA Comment ID: 19759 

EPA Comment Code: 6120 

 

Comment: My thoughts on the need to regulate perchlorate in our drinking water is this. Never 

before in my life have I met more people with Thyroid problems. Including people in my own 

family. Perchlorate was once used by the medical practices to regulate a person's thyroid. Then it 

must be very important to keep this away healthy bodies. Children are the most vulnerable and we 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 585 of 1099

don't need to add more chemicals into their systems. If we can prevent it, we should. An ounce of 

prevention is worth a pound of cure! 

Sincerely, Trudi Ferguson 

Response: See response to comment code 6120. 

Commenter Name: Judith Gardiner 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0238 

EPA Comment ID: 19760 

EPA Comment Code: 6120 

 

Comment: Protect the general public before industry interests. Please do not allow perchlorate in 

drinking water at concentrations so much higher than previously thought safe. 

Judith K. Gardiner 

Response: See response to comment code 6120. 

Commenter Name: R. DeLauro 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0239 

EPA Comment ID: 19761 

EPA Comment Code: 6120 

 

Comment: Allowing Perchlorate in drinking water isn't acceptable. So many people have 

compromised immune systems, and aren't yet aware of it. Allowing toxins in the water could be 

considered tantamount to slow, premeditated murder in auto immune cases. How can you allow 

this? 

No amount of poisons are safe in the body. None. 

EPA, Environmental PROTECTION Agency. Are you protecting the public or the corporations? 

Response: See response to comment code 6120. 

Commenter Name: D.E. Wedge 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0244 

EPA Comment ID: 19762 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPA’s refusal to regulate Perchlorate under the 

Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

Perchlorate is a highly reactive oxidation agent and has been shown to have significant biological 

activity damaging to both animals and humans. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 586 of 1099

I understand it has been detected in large numbers of drinking water sources in the United States, 

potentially affecting millions of Americans. 

The Safe Drinking Water Act mandates that the EPA must set a standard for such substances, in 

order to protect the health of our citizens. 

Thank you, D. E. Wedge 6591 Maplegrove St. Oak Park, CA 91377 

Response: See response to comment code 6120. 

Commenter Name: C. Curtin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0245 

EPA Comment ID: 19763 

EPA Comment Code: 6120 

 

Comment: I believe like MDs for social respnsibility that this would be injurious to health. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0248 

EPA Comment ID: 19764 

EPA Comment Code: 6120 

 

Comment: This decision is harmful topublic health! 

Response: See response to comment code 6120. 

Commenter Name: T. Davis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0249 

EPA Comment ID: 19765 

EPA Comment Code: 6120 

 

Comment: Your decision not to set a percholorate standard is harmful to the health of the citizens 

of the USA. By failing to set a standard, you have not lived up to your mission to product Americans 

from pollutants. This is shameful. 

Response: See response to comment code 6120. 

Commenter Name: M. Mandel 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0250 

EPA Comment ID: 19766 

EPA Comment Code: 6120 
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Comment: Docket ID No. EPA-HQ-OW- 2008-0068 Drinking Water: Preliminary Regulatory 

Determination on Perchlorate I recently moved to Phoenix Arizona and learned upon arrival that 

Perchlorate is a risk factor in the local water supply due to contamination of the ground water. Since 

the EPA did not protect this vital resource for our health and safety at the time the damage was 

done, it should at least protect us now and into the future. Raising the legal limit protects the 

interests of polluters, not the public health. Please do not approve such a change in the regulation of 

this contaminant. M. Mandel 

Response: See response to comment code 6120. 

Commenter Name: J.B. Goss 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0251 

EPA Comment ID: 19767 

EPA Comment Code: 6120 

 

Comment: Against ANY increase in perchlorate. How can you even consider such a thing? 

JB Goss 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0254 

EPA Comment ID: 19768 

EPA Comment Code: 6120 

 

Comment: This seems outrageous to me. We know perchlorate at current levels is harmful to 

human health -- why on earth do you refuse to regulate it? Thyroid disorders are serious and can 

compromise the health of this and future generations. Please take better action. 

Response: See response to comment code 6120. 

Commenter Name: P. Medeiros 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0256 

EPA Comment ID: 19769 

EPA Comment Code: 6120 

 

Comment: Return regulations to safe levels of perchlorate in water supply and throughout the food 

chain. 

I have high levels I am now experiencing thyroid problems, I face removal of part of my thyroid as 

the only means to mitigate the signs and symptoms of my thyroid condition. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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I see a direct correlation to excess ive levels of perchlorate being allowing into our water supply and 

food chain. 

It is your vested responsibility to oversee environmental conditions to prevent the American people 

from diseases and conditions detrimental to their health and well being and this issue must be 

seriously addressed in good faith or you are failing in your responsibilities to citizens. Thank you 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0257 

EPA Comment ID: 19770 

EPA Comment Code: 6120 

 

Comment: Please regulate perchlorate in drinkng water. Your decision to not regulate perchlorate is 

harmful to public health. It is 15 times higher than in 2002 and millions of Americans are exposed to 

unsafe levels. Please do not put people's health at risk. 

Response: See response to comment code 6120. 

Commenter Name: D. Sawyer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0258 

EPA Comment ID: 19771 

EPA Comment Code: 6120 

 

Comment: This is harmful to public health !!!!! 

Response: This is not a comment, no response is necessary. 

Commenter Name: D. Sawyer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0259 

EPA Comment ID: 19772 

EPA Comment Code: 6120 

 

Comment: This decision is harmful to public health ! 

Response: This is not a comment, no response is necessary. 

Commenter Name: Noel Smith 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0260 

EPA Comment ID: 19773 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Comment: Get Serious. The EPA is supposed to protect the health of the environment and US 

citizens, not aid business. I find this proposal to be appalling. Is there no shame in this 

administration? Noel Smith, Auburn, Maine 

Response: This is not a comment, no response is necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0261 

EPA Comment ID: 19774 

EPA Comment Code: 6120 

 

Comment: Please regulate our water! 

Response: See response to comment code 6120. 

Commenter Name: Rick Sandlin 

Commenter Organization: Global Wellness and Nutrition 

EPA Document ID: EPA-HQ-OW-2008-0692-0264 

EPA Comment ID: 19775 

EPA Comment Code: 6120 

 

Comment: We are VERY CONCERNED ABOUT THE QUALITY OF OUR TAP WATER 

TODAY! EPA: Please, No Perchlorate in Our Tap Water! This decision is harmful to public health! 

Response: See response to comment code 6120. 

Commenter Name: 

Commenter Organization: Alliance for Democracy 

EPA Document ID: EPA-HQ-OW-2008-0692-0265 

EPA Comment ID: 19776 

EPA Comment Code: 6120 

 

Comment: I keep hearing that tap water is safer than bottled. Then I get a notice that the EPA does 

not regulate perchlorate in the Nation's drinking water. In my opinion, it is your major job to see 

that what people in the United States are eating or drinking are not negatively affected by substances 

being put into the environment by anyone - persons or corporations. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Renee Watkins 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0266 

EPA Comment ID: 19777 

EPA Comment Code: 6120 

 

Comment: It's wrong to create major health problems for innocent people in order to protect the 

waste disposal practices of certain entities, public or private, who wish to avoid regulation. You may 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 590 of 1099

think you are protecting economic welfare, but you are actually contributing to the decline of this 

country, in health and in safety. Renee Watkins 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0268 

EPA Comment ID: 19778 

EPA Comment Code: 6120 

 

Comment: I feel this decision is harmful to public health! 

Response: See response to comment code 6120. 

Commenter Name: B. Cramer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0269 

EPA Comment ID: 19779 

EPA Comment Code: 6120 

 

Comment: The EPA should reverse its decision and set a more stringent standard regulating the 

amount of perchlorate in drinking water. This dangerous chemical is linked to thyroid problems in 

pregnant women, newborns and young children. Perchlorate has been found in the drinking water in 

35 states in the U.S. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0272 

EPA Comment ID: 19780 

EPA Comment Code: 6120 

 

Comment: I disagree with the relaxation of perchlorate level standards in our drinking water 

supplies. 

Response: See response to comment code 6120. 

Commenter Name: Gerson T Lesser, MD 

Commenter Organization: Department of Geriatrics, Mt Sinai School of Medicine 

EPA Document ID: EPA-HQ-OW-2008-0692-0277 

EPA Comment ID: 19783 

EPA Comment Code: 6120 

 

Comment: Gentlemen, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 591 of 1099

Perchlorate in the water supply is a potential hazard, especially for thyroid disease, and especially in 

the very young and pregnancy. It would be unwise to loosen restrictions on content of this in 

drinking water. 

G.T. Lesser, MD, Asst Professer 

P.S. These comments are mine and not necessarily those of the Medical School. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0206 

EPA Comment ID: 19784 

EPA Comment Code: 6120 

 

Comment: No perchlorate in my water!!! 

Response: See response to comment code 6120. 

Commenter Name: J Monson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0209 

EPA Comment ID: 19785 

EPA Comment Code: 6120 

 

Comment: We need to tighten drinking water restrictions, not loosen them. The general public is 

already exposed to far too many toxins in America's water supply, from perchlorate to prescription 

drugs. Loosening the regulations is a bad idea. Please don't change the perchlorate level that is 

acceptable in our water. 

Response: See response to comment code 6120. 

Commenter Name: Lisa Bromfield 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0211 

EPA Comment ID: 19786 

EPA Comment Code: 6120 

 

Comment: Science gives us more and more examples of how the chemicals we are adding to the 

water and soil of our planet are being found in human bodies. We need LESS chemicals in the water 

- not more!! Please consider the health of not only humans but the plants and animals with whom 

we share the planet and on whom we depend. 

Sincerely, Lisa Bromfield Stephens City, VA 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0212 

EPA Comment ID: 19787 

EPA Comment Code: 6120 

 

Comment: No perchlorate in my drinking water! 

Response: See response to comment code 6120. 

Commenter Name: Alexander N. Gunn II, M.D., FACS 

Commenter Organization: Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0213 

EPA Comment ID: 19788 

EPA Comment Code: 6120 

 

Comment: I am deeply offended that you would consider allowing near-toxic levels of perchlprate 

in drinking water. This is a marked derogation of responsibility which is intolerable to the average 

American citizen. We demand that you reduce this ruling at once. 

Sincerely, Alexander N. Gunn II, MD, FACS 

Response: See response to comment code 6120. 

Commenter Name: Don Thompson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0214 

EPA Comment ID: 19789 

EPA Comment Code: 6120 

 

Comment: I cannot believe that the proposed level of Perchlorate to be allowed in drinking water is 

safe. Our town was has just finished a very expensive water treatment facility to reduce the arsenic 

levels in our drinking water. It was an expenditure which I felt was justified and I believe that the 

expenditures necessary to lower potentially harmful levels of Perchlorate should also be required. 

Sincerely, Don Thompson 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0215 

EPA Comment ID: 19790 

EPA Comment Code: 6120 

 

Comment: Perchlorate levels in drinking water supplies should be reduced not increased. 

Perchlorate levels in water are currently unacceptable and should most definitely not have standards 

that would increase allowable levels. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 593 of 1099

Response: See response to comment code 6120. 

Commenter Name: S.T. Joyce 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0216 

EPA Comment ID: 19791 

EPA Comment Code: 6120 

 

Comment: This standard is inadequate and unacceptable. When did the EPA become an 

organization that is not dedicated to protecting citizens? 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0218 

EPA Comment ID: 19792 

EPA Comment Code: 6120 

 

Comment: I am an individual, living in Palo Alto, CA Perchlorate is KNOWN to be unhealthy. 

Therefore I consider it IMPERATIVE that regulations be made to limit it. Actually, if we were to 

use the Precautionary Principle, we would not allow ANY AMOUNT in our water, until it could be 

proven that some amount was NOT unhealthy/damaging. However since we don't operate that 

way, and since without regulations, those who produce/ use perchlorate won't bother to be careful, 

we need a specified limit. 

Response: See response to comment code 6120. 

Commenter Name: Diana Smith 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0219 

EPA Comment ID: 19793 

EPA Comment Code: 6120 

 

Comment: EPA-HQ-OW-2008-0692 

I think it is important to keep Perchlorate levels very low - at least to 2002 levels thank you. 

Diana Smith 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0220 

EPA Comment ID: 19794 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 594 of 1099

 

Comment: We need to keep our water as pure as possible. There should be NO perchlorate in tap 

water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0222 

EPA Comment ID: 19795 

EPA Comment Code: 6120 

 

Comment: A public comment concerning levels of Perchlorate in drinking water. Refusing to 

regulate this harmful chemical in our drinking water is unacceptable. I urge you to consider the 

health of the American public, most especially those of highest risk, pregnant women, children and 

newborns. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0224 

EPA Comment ID: 19796 

EPA Comment Code: 6120 

 

Comment: Please do not allow perchlorate to contaminate our drinking water. It is a safety hazard 

that is not necessary and harmful especially to children and pregnant women. Aren't we causing 

enough harm to our planet and our health without adding a new harmful elememnt that we will 

need to clean up? 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0226 

EPA Comment ID: 19797 

EPA Comment Code: 6120 

 

Comment: Please regulate perchulate in drinking water. Our health depends on it. We are exposed 

to UNSAFE levels of it in OUR drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Glenn Shean, Ph.D. 

Commenter Organization: Hamptom Roads Counseling 

EPA Document ID: EPA-HQ-OW-2008-0692-0307 

EPA Comment ID: 19798 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 595 of 1099

 

Comment: Allowing increased levels of perchorate in our drinking water is a crime. who does the 

EPA work for industry or the citizens? For the recent past the rhetorical question must be answered 

as INDUSTRY! 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0308 

EPA Comment ID: 19799 

EPA Comment Code: 6120 

 

Comment: Perchlorate does not belong in our drinking water - period! 

Response: See response to comment code 6120. 

Commenter Name: Bonnie Mandell-Rice 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0310 

EPA Comment ID: 19800 

EPA Comment Code: 6120 

 

Comment: Please do not allow perchlorate in our drinking water. There already are too many 

chemicals and pharmaceuticals in the water supply. Even if in isolation one such thing would be 

"safe," we have no idea about how they all interact. We already know perchlorate is dangerous. Do 

not allow it to be added to the mix. 

Bonnie Mandell-Rice Broomfield,CO 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0311 

EPA Comment ID: 19801 

EPA Comment Code: 6120 

 

Comment: No rocket fuel in my drinking water, please! 

You morons shouldn't have to be TOLD something like this! 

Nov. 4 couldn't come soon enough!!! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 596 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-0313 

EPA Comment ID: 19802 

EPA Comment Code: 6120 

 

Comment: There should be no perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0314 

EPA Comment ID: 19803 

EPA Comment Code: 6120 

 

Comment: Unless you're also going to approve insertion of rocket engines into the large intestine, 

any level of Perchlorate in the water supply in unacceptable. 

http://www.youtube.com/watch?v=1rAsoLm1Ges 

Thanks for listening. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0317 

EPA Comment ID: 19804 

EPA Comment Code: 6120 

 

Comment: Perchlorate levels need to be monitored as they can be harmful to the health of many 

Americans. 

Response: See response to comment code 6120. 

Commenter Name: Dr. Thomas Clark 

Commenter Organization: Southern Appalachian Forestry Task Force (SAFTF) 

EPA Document ID: EPA-HQ-OW-2008-0692-0318 

EPA Comment ID: 19805 

EPA Comment Code: 6120 

 

Comment: The U.S. desperately needs clean water for the health of our children. Please help 

strengthen the regulations which affect our water supplies. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0319 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 597 of 1099

EPA Comment ID: 19806 

EPA Comment Code: 6120 

 

Comment: Why are we putting ourselves at risk when we don't have to??? As a thyroid cancer 

survivor, I want to know that this chemical, which has been proven to affect the thyroid, is regulated 

at a safe level. It has been found in the drinking water of 35 states, so we need to do something. 

Right now we're behind where we were before, not ahead!!! The maximum safe level for perchlorate 

in drinking water is now 15 times higher than what the EPA declared safe in 2002. According to 

Physicians for Social Responsibility, under this new standard, more than 16 million Americans are 

exposed to unsafe levels of perchlorate in their drinking water, and independent analysis shows 

anywhere from 20 to 40 million Americans at risk. It's time to start making us safer! 

Response: See response to comment code 6120. 

Commenter Name: Erik Lokensgard 

Commenter Organization: Division of the Biological Sciences, University of Chicago 

EPA Document ID: EPA-HQ-OW-2008-0692-0320 

EPA Comment ID: 19807 

EPA Comment Code: 6120 

 

Comment: Concerning: EPA-HQ-OW-2008-0692 Docket Title Drinking Water: Preliminary 

Regulatory Determination on Perchlorate Docket Type Nonrulemaking Document ID EPA-HQOW-2008-0692-0001 

October 15, 2008 

Dear Reader, 

I am a fourth year biology major at the University of Chicago and am deeply concerned about the 

current dangerously high perchlorate allowance. I recommend that regulations be made immediately 

limiting the industrial output of perchlorate and perchlorate related compounds. Perchlorate 

interferes with iodide uptake in the thyroid, and the news of significant levels being found in breast 

milk and elsewhere is disturbing. If a woman cannot safely breastfeed her child, we are in dire 

straights indeed. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0321 

EPA Comment ID: 19809 

EPA Comment Code: 6120 

 

Comment: Are you guys nuts! We don't want 15 times more Perchlorate that we had in 2002. A jet 

fuel! Shame on you! Do all you people drink bottled water and just think that what people don't 

know won't hurt them? I drink tap water because I thought I could trust the federal government! 

Please clean up our water. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 598 of 1099

Response: See response to comment code 6120. 

Commenter Name: Jennifer Sass, PhD 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2008-0692-0322 

EPA Comment ID: 19811 

EPA Comment Code: 6120 

 

Comment: 

October 17, 2008 

Docket identification (ID): EPA-HQ-OW-2008-00692 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0323 

EPA Comment ID: 19814 

EPA Comment Code: 6120 

 

Comment: EPA-HQ-OW- 2008-0068 

Why would anyone want to drink anything that's in rocket fuel??? 

Would you? 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Sarah Woodwide Gallagher 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0324 

EPA Comment ID: 19815 

EPA Comment Code: 6120 

 

Comment: Ladies/Gentlemen: 

How in good conscience can you countenance endangering the health of Americans with this flawed 

regulation? 

Most sincerely, 

Sarah Woodwide Gallagher 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Clif Steinberg 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 599 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0326 

EPA Comment ID: 19816 

EPA Comment Code: 6120 

 

Comment: It is time to stop the madness. Perchlorate is among the many toxic contaminants that 

we have poisoned our environment with, and now rather than protect ourselves and clean up our 

mess we will just drink our own poison. Insanity! Maybe criminal. 

-Clif Steinberg 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0331 

EPA Comment ID: 19817 

EPA Comment Code: 6120 

 

Comment: I want my water regulated and I think that this decision is harmful to our health and 

needs to be changed. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0333 

EPA Comment ID: 19819 

EPA Comment Code: 6120 

 

Comment: No... I don't need any more Perchlorate in my water or my atmosphere. I live next to 

3M. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0335 

EPA Comment ID: 19820 

EPA Comment Code: 6120 

 

Comment: I think this decision is harmful to public health! 

Response: See response to comment code 6120. 

Commenter Name: Stephen F. Lynch 

Commenter Organization: Granite Medical Group 

EPA Document ID: EPA-HQ-OW-2008-0692-0336 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 600 of 1099

EPA Comment ID: 19824 

EPA Comment Code: 6120 

 

Comment: I am a practicing physician of Internal Medicine and Pediatrics. I have researched the 

issue of acceptable perchlorate levels in drinking water, and have concluded that the current levels 

are TOO HIGH, not too low. Allowing higher levels will adversely affect the health of US citizens, 

including yours! Do NOT raise the current levels. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0337 

EPA Comment ID: 19825 

EPA Comment Code: 6120 

 

Comment: This is a public comment regarding perchlorate levels in drinking water. I urge you to 

set reasonable levels for acceptable perchlorate concentrations in drinking water. These levels should 

be at or below those deemed "safe" by the EPA itself in 2002. The American public has the right to 

safe drinking water. 

Response: See response to comment code 6120. 

Commenter Name: D Timmerman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0340 

EPA Comment ID: 19826 

EPA Comment Code: 6120 

 

Comment: We ask that perchlorate not be added to water. It is a chemical that is very toxic and 

could lead to ailments to the population. 

Response: Perchlorate is not added to water. EPA has determined to regulate perchlorate in 

drinking water. See response to comment code 6120. 

Commenter Name: Edith A. Martin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0341 

EPA Comment ID: 19828 

EPA Comment Code: 6120 

 

Comment: I am an educated consumer and an American citizen. I am against the current allowable 

level of perchlorate in our drinking water. This is just one more ruling that the EPA has not 

enforced properly to ensure that the public is protected from known toxins in our environment, 

whether it is in our air or water. Please ensure the safety of our water in this case by adjusting the 

level of perchlorate. 

Thank you, Edith A. Martin 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 601 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0343 

EPA Comment ID: 19829 

EPA Comment Code: 6120 

 

Comment: Do not allow unsafe chemicals in our water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0344 

EPA Comment ID: 19830 

EPA Comment Code: 6120 

 

Comment: You're not helping! Perchlorate levels in drinking water as approved by the Bush EPA is 

unacceptable! 

Response: See response to comment code 6120. 

Commenter Name: Thomas Armstrong 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0348 

EPA Comment ID: 19831 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

I do not want perchlorate in my drinking water. 

Thomas Armstrong 

Response: See response to comment code 6120. 

Commenter Name: Lynn and Harrison Houston 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0349 

EPA Comment ID: 19832 

EPA Comment Code: 6120 

 

Comment: Dear Sirs, 

We need a drinking water standard. this is harmful to public health as these chemicals are toxic. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 602 of 1099

Sincerely, Lynn and Harrison Houston Satellite Beach, Florida 32937-3000 

Response: See response to comment code 6120. 

Commenter Name: C. Fletcher 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0351 

EPA Comment ID: 19833 

EPA Comment Code: 6120 

 

Comment: As a registered nurse, I am concerned that no standard regarding the currently allowable 

amounts of perchlorate in drinking water exists. Perchlorate affects the function of the thyroid 

gland, a gland that is essential to human health. Perchlorate is found in the water drunk by humans 

in at least 35 states. It is essential that the EPA set standards for levels of perchlorate in drinking 

water in order to address the problem and promote public health. 

Response: See response to comment code 6120. 

Commenter Name: S. McCarthy 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0355 

EPA Comment ID: 19836 

EPA Comment Code: 6120 

 

Comment: This is an unsafe decision! Perchlorate in drinking water must be limited or E- liminated. 

Reconsider this decision with its increased danger for our tap water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0359 

EPA Comment ID: 19837 

EPA Comment Code: 6120 

 

Comment: As a concerned citizen, I urge you to set a cautious standard for regulating perchlorate 

in drinking water. 

I worked at Rocketdyne in Canoga Park in the late 1960's, where I began having thyroid problems 

for the first time and have subsequently developed autoimmune issues and chemical sensitivities. 

Please consider that the human immune system can tolerate only a finite amount of toxicity from all 

sources before it begins to break down. Perchlorate may be only one of many hazards in our water 

system but that does not make it insignificant enough to overlook. 

The role of the Environmental Protection Agency is to protect us from harmful substances. Please 

exercise diligence in carrying out your role. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 603 of 1099

Commenter Name: Elizabeth Sheehan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0362 

EPA Comment ID: 19838 

EPA Comment Code: 6120 

 

Comment: I am extremely concerned about the increased risk of exposure to harmful toxins such 

as perchlorate in tap water. This is a significant public health issue, putting young children, pregnant 

women, unborn children at risk. I urge you to re-examine your standards of acceptance regarding 

perchlorate. I thank you for considering my comment and rethinking policies. 

Sincerely, Elizabeth Sheehan 

Response: See response to comment code 6120. 

Commenter Name: M.E. Harte 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0363 

EPA Comment ID: 19839 

EPA Comment Code: 6120 

 

Comment: please regulate perchlorate in drinking water! That is a known carcinogen and should be 

regulated. Would you like one of your kids drinking water contaminated with that stuff? Please 

regulate it. Thanks! 

Response: See response to comment code 6120. 

Commenter Name: Terrence L. Horan, D.D.S. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0365 

EPA Comment ID: 19840 

EPA Comment Code: 6120 

 

Comment: EPA representatives, Perchlorate has been show to be detrimental to human health. 

That is reason enough to restrict its presence in drinking water. Whatever industry has to do to keep 

it out of our environment, they must be forced to do. Anything less is irresponsible. 

Terrence L. Horan, D.D.S. 

Response: See response to comment code 6120. 

Commenter Name: Robert N. Milling 

Commenter Organization: Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0366 

EPA Comment ID: 19841 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 604 of 1099

Comment: Regulate Pechlorate in drinking water 

Response: See response to comment code 6120. 

Commenter Name: H.N Hanna 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0367 

EPA Comment ID: 19842 

EPA Comment Code: 6120 

 

Comment: I am dismayed that the EPA has refused to set an appropriate drinking water standard 

for perchlorate. This rocket fuel chemical has been linked to thyroid problems in pregnant women, 

newborns and young children. The maximum safe level is now 15 times higher than what the EPA 

declared safe in 2002. The new standard puts 20 to 40 million of us at risk. I think the EPA should 

be doing a better job of protecting us; that is what it was set up to do, and that is what we taxpayers 

are paying for the EPA to do. 

Response: See response to comment code 6120. 

Commenter Name: Mary Beth Sullivan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0370 

EPA Comment ID: 19843 

EPA Comment Code: 6120 

 

Comment: To Whom This May Concern: 

I write to insist that the EPA do the job it was created to do, and REGULATE the lowest amount 

possible of perchlorate in water. 

Response: See response to comment code 6120. 

Commenter Name: Mary Beth Sullivan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0370 

EPA Comment ID: 19845 

EPA Comment Code: 6120 

 

Comment: The EPA exists to PROTECT Americans from the predators that manipulate science; 

PROTECT our children from the chemicals that do them harm (indeed permanent damage). Career 

scientists at the EPA know the right thing to do on this issue. I beg you to have the courage to do 

the right thing. Leave politicians and well-funded lobbyists out of this decision. 

Please, provide tight regulation on perchlorate. 

While you're at it, demand that the polluters pay to clean up the mess they've made -- we all know 

they've taken an obscene amount of our tax dollars as profit! 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 605 of 1099

Sincerely, Mary Beth Sullivan 212 Centre Street Bath, Maine 04530 207 443 9502 

mbsull@mindspring.com 

Response: See response to comment code 6120. Requiring polluter payment is outside the scope of 

this rule; no response is necessary. 

Commenter Name: K. Hannigan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0371 

EPA Comment ID: 19846 

EPA Comment Code: 6120 

 

Comment: Please do not put Perchlorate in our water. 

Response: Perchlorate is not added to water. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0372 

EPA Comment ID: 19847 

EPA Comment Code: 6120 

 

Comment: So it's safe to drink rocket fuel? Really? And we're supposed to believe there are no 

politics in government science and that the EPA cares about the health of Americans? Really??? 

Perchlorate is unsafe. If you doubt that, please feel free to administer it to members of your own 

families but DON'T force citizens counting on clean water to drink it. 

Don't become the Environmental Pollution Agency. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Judith Weiss 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0374 

EPA Comment ID: 19848 

EPA Comment Code: 6120 

 

Comment: I understand that the EPA is considering raising the bar on "safe" levels of byproducts 

of rocket fuel in our drinking water. This is the kind of politically driven lack of concern for citizen 

health that we've come to expect from our government. 

I object to this agency playing cancer roulette with my health and the health of the nation. 

Until and unless each water contaminant is tested for safety by the Ames test or another reputable 

test you should NOT deem any levels of rocket fuel or its byproducts as safe in food water or drink. 

Let's see some concern for the public good in your policies. Judith Weiss 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 606 of 1099

Response: See response to comment code 6120. 

Commenter Name: Sherrie Riggio 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0375 

EPA Comment ID: 19849 

EPA Comment Code: 6120 

 

Comment: Please keep the levels of perchlorate in the drinking water at the levels suggested by 

safety standards declared by the EPA in 2002. It seems like we are going backwards with safety 

issues instead of forward. The public's health must take priority over politics. Please. Sherrie Riggio. 

Response: See response to comment code 6120. 

Commenter Name: Peter Roloff 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0376 

EPA Comment ID: 19850 

EPA Comment Code: 6120 

 

Comment: As a concerned citizen I can think of no permissible levels of Perchlorate that should be 

allowed in our fresh water sources, period, end of discussion. sincerly, Peter Roloff 

Response: See response to comment code 6120. 

Commenter Name: J. Koss, MD 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0377 

EPA Comment ID: 19851 

EPA Comment Code: 6120 

 

Comment: PERCHLORATE, LIKE ALL MAN MADE CHEMICALS POSE UNCERTAIN 

AND UNTESTED RISKS TO MY PATIENTS. EUROPE demands proof of safety to add 

chemicals to the environment, let alone drinking water.Adults, especially children, run risks 

potentially discoverable AFTER 10-20 years of exposure. WHAT WILL THE GOVERNMENT 

DO THEN? It will be too late for many victims by then. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0379 

EPA Comment ID: 19852 

EPA Comment Code: 6120 

 

Comment: I would want to know drinking water was safe for my children and grandchildren. 

Wouldn't you? 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 607 of 1099

Response: This is not a comment, a response is not necessary. 

Commenter Name: M. Soule 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0381 

EPA Comment ID: 19853 

EPA Comment Code: 6120 

 

Comment: No perchlorate in our drinking water!!! TOXIC AND HARMFUL!!! 

Response: See response to comment code 6120. 

Commenter Name: Edwards Mills 

Commenter Organization: Kidem Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-0383 

EPA Comment ID: 19854 

EPA Comment Code: 6120 

 

Comment: Please implement a meaningful standard for perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0385 

EPA Comment ID: 19855 

EPA Comment Code: 6120 

 

Comment: Set a Federal standard for perchlorate! Protect the public health! 

Response: See response to comment code 6120. 

Commenter Name: Brian Dewhirst, MD 

Commenter Organization: Palmetto Primary Care Physicians 

EPA Document ID: EPA-HQ-OW-2008-0692-0387 

EPA Comment ID: 19856 

EPA Comment Code: 6120 

 

Comment: I am a family physician in South Carolina and take care of both adults and children. I 

want to express my deep concern about the EP's decision on addressing perchlorate in water. This 

chemical is known to be harmful and exposure through water could pose a serious danger to public 

health. Sincerely, Dr. Brian Dewhirst, MD Palmetto Primary Care Physicians Charleston, SC 

Response: See response to comment code 6120. 

Commenter Name: B. Meyer 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 608 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-0388 

EPA Comment ID: 19857 

EPA Comment Code: 6120 

 

Comment: I am writing to support adding Perchlorate regulations under the Safe Water Drinking 

Act (Docket ID EPA-HQ-2008-0692) This chmeical, used in rocket fuel, is linked to thyroid 

problems in pregnant women, children and newborns. The EPA must regualte the chemical in 

drinking water.Millions are threatened, 16 million in 35 states. Protect our health. 

Response: See response to comment code 6120. 

Commenter Name: R. Sharp 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0391 

EPA Comment ID: 19858 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPA's refusal to regulate Perchlorate under the 

Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

This is a bad decision. Keep Perchlorate out of drinking water. 

Response: See response to comment code 6120. 

Commenter Name: D Camp 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0392 

EPA Comment ID: 19859 

EPA Comment Code: 6120 

 

Comment: Water is more precious than gold, and highly needed healthy water for all living things. 

All the things found in surface water ends up in our bodies, so stop harmful chemicals in water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0393 

EPA Comment ID: 19860 

EPA Comment Code: 6120 

 

Comment: Hypothyroidism is insidious and not diagnosed in time to avoid developmental 

deficiencies in children and dementia in old people.Perchlorate intake by children must be prevented 

at any cost. The standard for perchlorate in drinking water must be tightened. 

Response: See response to comment code 6120. 

Commenter Name: S. King 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 609 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0394 

EPA Comment ID: 19861 

EPA Comment Code: 6120 

 

Comment: It is dangerous for the EPA to raise the amount of perchlorate allowed in public driking 

water. Keep the old standard and protect the health of U.S. citizens. 

Response: See response to comment code 6120. 

Commenter Name: M.M. Foxton 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0399 

EPA Comment ID: 19862 

EPA Comment Code: 6120 

 

Comment: Please keep American drinking water safe. 

Response: See response to comment code 6120. 

Commenter Name: E. Heilman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0401 

EPA Comment ID: 19863 

EPA Comment Code: 6120 

 

Comment: The EPA has a responsibility to protect the health of US citizens and is obligated to 

regulate and minimize the amount of perchlorate found in drinking water -- it is known to be 

harmful to pregnant women and children. Take responsibility now, do your job of protecting 

PEOPLE not companies, and regulate (minimize) the amount of perchlorate in American drinking 

water. Do the right thing. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0407 

EPA Comment ID: 19864 

EPA Comment Code: 6120 

 

Comment: This is outrageous, I want to know that my drinking water is safe and free of anything 

harmful to my health. It's not acceptable to have unsafe levels of perchlorate in our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Tim Mathews 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0408 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 610 of 1099

EPA Comment ID: 19865 

EPA Comment Code: 6120 

 

Comment: I strongly believe that the percholate levels in drinking water should be restricted much 

more conservatively. 

Thank You, 

Tim Mathews 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0409 

EPA Comment ID: 19866 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPA's refusal to regulate Perchlorate under the 

Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

At least six of my friends and family members have serious thyroid conditions, probably due to 

environmental exposures. This is epidemic, and it's no time to allow MORE perchlorate in drinking 

water, as it is something already known to help cause thyroid problems in pregnant women, 

newborns and young children. 

You know how widespread perchlorate exposure is now in America. Setting a standard for it is a real 

step toward health risk reduction. Choosing not to regulate is choosing more disease, particularly for 

children. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0411 

EPA Comment ID: 19867 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPA's refusal to regulate Perchlorate under the 

Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

Perchlorate is a dangerous chemical that is currently found in the drinking water of 35 states. I urge 

you to set a standard for perchlorate in accordance with the Safe Drinking Water Act. Please protect 

American's health. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 611 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0412 

EPA Comment ID: 19868 

EPA Comment Code: 6120 

 

Comment: Fresh, healthy and pure drinking water is a human right, whether or not a government 

agency wants to accept that fact. A human right! No single source should be able to alienate the 

people from that right. Therefor it is the obligation of those of power--whom the people have 

elected to represent them--to protect the rights of their constituents. Please do whatever you can to 

keep perchlorate as well as other toxic substances from the People's drinking water. 

Response: See response to comment code 6120. 

Commenter Name: K. Dalby 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0417 

EPA Comment ID: 19869 

EPA Comment Code: 6120 

 

Comment: perchlorate is unsafe for consumption -- please keep out of drinking water! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0418 

EPA Comment ID: 19870 

EPA Comment Code: 6120 

 

Comment: I am outraged to learn that while perchlorate has been detected in the water supplies of 

two-thirds of the states, there is no plan to create a minimum 

acceptable level of this chemical. 

Response: See response to comment code 6120. 

Commenter Name: P. Incao 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0419 

EPA Comment ID: 19871 

EPA Comment Code: 6120 

 

Comment: Perchlorate is a chemical in rocket fuel that has been linked to thyroid problems in 

pregnant women, newborns and young children. Not regulating this harmful chemical in our 

drinking water is unacceptable. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 612 of 1099

Commenter Name: Masha Etkin MD, PhD 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0420 

EPA Comment ID: 19872 

EPA Comment Code: 6120 

 

Comment: To EPA: Please regulate perchlorate in drinking water in accordance with the Save 

Drinking Water Act. 

Thank you, Masha Etkin MD, PhD 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0425 

EPA Comment ID: 19874 

EPA Comment Code: 6120 

 

Comment: I find it criminally obscene that there is no regulation of perchlorate in the water supply. 

I find it convenient that the EPA has been repopulated with corporate advocates instead of those 

truly wishing to serve the public. 

Response: See response to comment code 6120. 

Commenter Name: E. Manire-Gatti 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0426 

EPA Comment ID: 19875 

EPA Comment Code: 6120 

 

Comment: EPA must regulate the amount of perchlorate in drinking water so that it does not cause 

harm. Perchlorate is known to cause throid problems in pregnant women, newborns, and small 

children. This chemical can lead to delayed and altered development in children. It can lead to the 

development of tumors. 

I understand that perchlorate is needed by the defense industry and its control will make its products 

more expensive. However, the health of the citizens of the United States is more important than 

spending more for weapons. Please remember our present and future generations when you 

consider the regulation of perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: C. DiBenedetto 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0430 

EPA Comment ID: 19876 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 613 of 1099

EPA Comment Code: 6120 

 

Comment: Please do not poison the people of America and our children. The EPA should regulate 

perchlorate in our drinking water, and the standards should not be lower than they are today -- they 

should be higher, if anything. 

Response: See response to comment code 6120. 

Commenter Name: Dorothea Leicher 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0431 

EPA Comment ID: 19877 

EPA Comment Code: 6120 

 

Comment: This is written by Dorothea Leicher, at 2303 Delancey Pl, Philadelphia, PA, 19103, as a 

Public Comment regarding EPA's refusal to regulate Perchlorate under the Safe Water Drinking Act 

(Docker ID EPA-HQ-OW-2008-0692) 

Perchlorate has been linked to thyroid problems in pregnant women, newborns and young children. 

As mother, this kind of risk to my daughter and her children is of great concern. 

Perchlorate is found in the drinking water of 35 states, so that regulating it would provide a 

significant protection for the public. 

Safe drinking water is an extremely important asset, and one that we will have to rely on increasingly 

as water becomes scarcer. the trust in tap water has already been assaulted by the bottled water 

industry and it is especially important now do everything to protect this public resource in the spirit 

of the Safe Water Drinking Act. Thank you for your time and attention. 

Response: See response to comment code 6120. 

Commenter Name: S. Carr 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0435 

EPA Comment ID: 19880 

EPA Comment Code: 6120 

 

Comment: Perchlorate toxicity is proven beyond doubt. Why is there a question about its' 

regulation? It is ridiculous to poison people on purpose although the U.S. chemical industry has 

been doing so for half a century. Most of the cancers, thyroid problems, and birth defects seem 

related to the chemical industry and the lack of proper regulation from the EPA. If the EPA cannot 

do better, they should start over with a new agency that can protect us and close this one down. 

Response: See response to comment code 6120. 

Commenter Name: B. Welsh 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0438 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 614 of 1099

EPA Comment ID: 19881 

EPA Comment Code: 6120 

 

Comment: Do not allow more Perchlorate in our drinking water! Our water continues to degrade in 

quality - in part by various pollutants which are virtually impossible to study in the combinations 

they'll actually appear in. These combinations are virtually impossible to study due to their large 

numbers, but evidence so far indicates that the total effect of these pollutants is worse than the sum 

of effects of the separate pollutants. 

Clean water is critical for life - and it's far cheaper and more sensible to keep the water clean rather 

than to clean it up after it's polluted. 

Response: See response to comment code 6120. 

Commenter Name: G. Miller 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0442 

EPA Comment ID: 19882 

EPA Comment Code: 6120 

 

Comment: I don't think any substance should be in our drinking water, except what our Creator 

put there. As far as any perchlorate is concerned, they don't belong in our water supply. If there is 

no way to eradicate it, then it should be the smallest amount possible. This seems like something the 

EPA should know without our input. There our so many diseases now that I feel are caused by the 

chemicals in our atmosphere; consequently, we don't want to allow this chemical in our water 

supply, which would endanger the health of our citizens. 

I strongly urge the EPA to set a high standard for our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: J. Rinker 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0444 

EPA Comment ID: 19883 

EPA Comment Code: 6120 

 

Comment: Perchlorate has a long history of use in rocket fuel and its has been shown to disrupt 

iodine uptake, which can lead to endocrine abnormalities in our most susceptible populations 

including pregnant women, newborns and small children. 

Given that it has been found in the drinking water of 35 states in the US, it is imperative that the 

EPA not only regularly review but regulate this chemical to protect our families and future heritage. 

As an occupational and environmental medicine physician I strongly urge that the EPA set a 

standard for perchlorate in our drinking water in order to protect American's health. Don't lose this 

opportunity to set regulations for reducing our health risks from chemically contaminated drinking 

water in accordance with the Safe Drinking Water Act. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 615 of 1099

Response: See response to comment code 6120. 

Commenter Name: A. R. Ehrlich, MD 

Commenter Organization: Group Health Cooperative Health Care 

EPA Document ID: EPA-HQ-OW-2008-0692-0445 

EPA Comment ID: 19886 

EPA Comment Code: 6120 

 

Comment: Perchlorate in drinking water should be limited. I understand that thus far the EPA has 

refused to do this, which puts millions of small children and pregnant women at risk from the 

harmful effects on the thyroid. 

A R Ehrlich, MD 

Response: See response to comment code 6120. 

Commenter Name: Jeoffry B. Gordon, MD, MPH 

Commenter Organization: Ocean Beach Medical Group 

EPA Document ID: EPA-HQ-OW-2008-0692-0448 

EPA Comment ID: 19887 

EPA Comment Code: 6120 

 

Comment: As apractici8ng physician with a devotion to environmental health diseases, it is my 

opinion that the preponderance of the available evidence would indicate that it is important to have 

a margin of safety by reducing the proposed level of perchlorate in drinking water by a factor of 20. 

Response: See response to comment code 6120. 

Commenter Name: Ellen M. Imbody 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0450 

EPA Comment ID: 19888 

EPA Comment Code: 6120 

 

Comment: As a retired public health comissioner, I urge you to regulate the Perchlorate which is 

now found in the drinking water in 35 states. Percholate is a dangerous chemical. Without regulation 

too many Americans risk being exposed to this 

chemical. With control of this chemical, you will be protecting our citizens health. 

Sincerely, 

Ellen M. Imbody Pinetop, AZ 

Response: See response to comment code 6120. 

Commenter Name: B. Regulinski 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 616 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0451 

EPA Comment ID: 19889 

EPA Comment Code: 6120 

 

Comment: The EPA needs to set a maximum level of pechlorate in drinking water. AS FAR AS I 

AM CONCERNED THERE IS NO SAFE LEVEL FOR FOREIGN CHEMICALS IN 

DRINKING WATER. There is already a shortage of clean drinking water in the world. Water is 

essential to life, and I resent the contamination of the little that the world has. Many wells in my area 

of Arizona have had to be closed because of chemicals from cleaning air plane engines and 

manufacture of computer chips. 

There is no excuse for allowing manufacturers to dump their waste water into the supply of clean 

drinking water. 

Response: See response to comment code 6120. 

Commenter Name: R. Sheridan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0452 

EPA Comment ID: 19890 

EPA Comment Code: 6120 

 

Comment: I would like to comment regarding EPA's refusal to regulate Perchlorate under the Safe 

Drinking Act (Docket ID EPA-HQ-OW-2008-0692. 

I think perchlorate should be regulated because it is a chemical in rocket fuel that has been linked to 

thyroid problems in pregnant women, newborns and young children. This harmful chemical should 

be regulated. It has been found in Alaska, as well as in 34 other states. According to the EPA's data 

it has been shown that we are at risk of being exposed to this chemical. 

I urge you to set a standard for perchlorate in accordance with the Safe Drinking Water Act. 

Ruth Sheridan, Anchorage, AK 

Response: See response to comment code 6120. 

Commenter Name: Catherine Moore 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0453 

EPA Comment ID: 19891 

EPA Comment Code: 6120 

 

Comment: Perchlorate is not something I can drink safely. I already have a huge problem with my 

thyroid which can cause heart failure and a number of other serious problems. Please find a way to 

monitor and clean up this toxic material which is finding its way into our drinking water. 

Many thanks, Catherine Moore, Oregon 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 617 of 1099

Response: See response to comment code 6120. 

Commenter Name: Grace Goldberg, DO 

Commenter Organization: MidCoast Maine Cares (MCMC) 

EPA Document ID: EPA-HQ-OW-2008-0692-0457 

EPA Comment ID: 19892 

EPA Comment Code: 6120 

 

Comment: Please remember that you are the Environmental Protection Agency. Please do not raise 

the acceptable level of perchlorates in drinking water. Thankyou 

Response: See response to comment code 6120. 

Commenter Name: David P. Kuter, M.D. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0458 

EPA Comment ID: 19893 

EPA Comment Code: 6120 

 

Comment: As a physician, I have reviewed the evidence and believe that more stringent guidelines 

are wise for the presence of perchlorate in water supplies. 

David P. Kuter, MD 3917 Regent Street, Madison, WI 53705 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0467 

EPA Comment ID: 19896 

EPA Comment Code: 6120 

 

Comment: Protect our nation's drinking water for rocket fuel, protect the health interests of 

pregnant women and children. 

Response: See response to comment code 6120. 

Commenter Name: N. O'Byrne 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0468 

EPA Comment ID: 19897 

EPA Comment Code: 6120 

 

Comment: We must regulate perchlorate in our drinking water to an acceptable standard that does 

not endanger public health. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 618 of 1099

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0471 

EPA Comment ID: 19900 

EPA Comment Code: 6120 

 

Comment: regulate perchlorate to the old standands. 

Response: See response to comment code 6120. 

Commenter Name: James R. and Mary Duplisea Palmer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0472 

EPA Comment ID: 19901 

EPA Comment Code: 6120 

 

Comment: My wife (Mary Duplisea-Palmer) and I (James R. Palmer) live at 66 Albert Pt. in Stetson, 

ME. This is our public comment regarding EPA's refusal to regulate Perchlorate under the Safe 

Drinking Water Act: Please continue to regulate this chemical according to the standard that was in 

place before this proposed change. Clean drinking water is so important to life, and, unfortunately, 

humankind has pollutted it too much already. Even using EPA's data, this chemical is wide-spread 

already. Continue to do the job your agency was created to do. 

Response: Perchlorate is not regulated in drinking water. See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0475 

EPA Comment ID: 19902 

EPA Comment Code: 6120 

 

Comment: The Environmental Protection Agency has formally refused to set a drinking-water 

standard for perchlorate, a chemical in rocket fuel that has been linked to thyroid problems in 

pregnant women, newborns and young children. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0475 

EPA Comment ID: 19904 

EPA Comment Code: 6120 

 

Comment: Is there something wrong with this picture? Why not help as an agency to be part of the 

Green Revolution by advocating for an entire network of workers whose sole goal would be to 

screen out (phase out) every iota of perchlorate from our drinking supply? And let's get more honest 

about flouride, too. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 619 of 1099

Response: See response to comment code 6120. The comment about flouride is outside the scope 

of this notice; no response is necessary. 

Commenter Name: Melvyn C. Thorne 

Commenter Organization: Johns Hopkins University 

EPA Document ID: EPA-HQ-OW-2008-0692-0482 

EPA Comment ID: 19905 

EPA Comment Code: 6120 

 

Comment: The regulatory limits on perchlorate in drinking water have been set irresponsibly too 

high. This is yet another of the reckless endangerments of public health produced by the Bush 

administration to pander to an unbalanced ideology of deregulation of industry. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0483 

EPA Comment ID: 19906 

EPA Comment Code: 6120 

 

Comment: Please, please, please put our health and welfare first. No perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: O. Yourke 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0485 

EPA Comment ID: 19907 

EPA Comment Code: 6120 

 

Comment: I think this decision is harmful to public health. No perchlorate should b allowed in 

drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0486 

EPA Comment ID: 19908 

EPA Comment Code: 6120 

 

Comment: Regulate percholate in all of our nations water supply. Do your job and protect the 

environment. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 620 of 1099

Commenter Name: Dave Weller, MPH 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0487 

EPA Comment ID: 19909 

EPA Comment Code: 6120 

 

Comment: EPA staffers, 

Please demand that all industrial chemicals be removed from our drinking water supply. Your 

current work in regulating perchlorate is especially important. Remove them from our water. 

Thank you, Dave Weller (MPH) 

Response: See response to comment code 6120. The comment about other industrial chemicals is 

outside the scope of this notice; no response necessary. 

Commenter Name: S. G. Gompf 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0490 

EPA Comment ID: 19910 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPAâ€TMs refusal to regulate Perchlorate under 

the Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

Perchlorate is component of rocket fuel. It has been linked to thyroid disease in pregnant women, in 

newborns and young children. It is incomprehensible, and indefensible, that the EPA has refused to 

regulate a dangerous chemical in the drinking water of American mothers and children. 

Response: See response to comment code 6120. 

Commenter Name: C. Gabriel 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0492 

EPA Comment ID: 19913 

EPA Comment Code: 6120 

 

Comment: Perchlorate is a known health hazard. The EPA's refusal to set standards for it is 

unconscionable, and an abrogation of it's charter. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0493 

EPA Comment ID: 19914 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 621 of 1099

Comment: Public Comment Regarding Immediate need to regulate Perchlorate under the Safe 

Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

As an physician and a mother I am quite concerned about the lack of regulation of Perchlorate, a 

chemical in rocket fuel, linked to thyroid problems in pregnant women, newborns and young 

children let alone other as of yet undetermined consequences. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0493 

EPA Comment ID: 19916 

EPA Comment Code: 6120 

 

Comment: Please use foresight and help to protect our drinking water by setting a standard for 

perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: Jan L. Crean, M.D. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0494 

EPA Comment ID: 19917 

EPA Comment Code: 6120 

 

Comment: I am writing to urge the EPA to control the contamination of our drinking water and, 

by extension, our food supply with regard to perchlorate. The following is medical information 

regarding this toxic chemical, per the EPA itself: 

PERCHLORATE 

The EPA has established an official reference dose (RfD) of 0.0007 mg/kg/day of perchlorate. This 

level is consistent with the recommended reference dose included in the National Academy of 

Science's January 2005 report. A reference dose is a scientific estimate of a daily exposure level that 

is not expected to cause adverse health effects in humans. Risk information about perchlorate and 

perchlorate salt. 

Perchlorate is a man-made anion commonly associated with the solid salts of ammonium, 

potassium, and sodium. Ammonium perchlorate is the mostly widely used perchlorate compound. It 

has also been found to occur naturally in certain highly arid environments. These salts are highly 

soluble in water, and because perchlorate adheres poorly to mineral surfaces and organic material, it 

can be very mobile in surface and subsurface aqueous systems. Also, since it is relatively inert in 

typical groundwater and surface water conditions, perchlorate contamination may persist for 

extended periods of time. 

Perchlorate interferes with iodide uptake into the thyroid gland. Because iodide is an essential 

component of thyroid hormones, perchlorate disrupts how the thyroid functions. In adults, the 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 622 of 1099

thyroid helps to regulate the metabolism. In children, the thyroid plays a major role in proper 

development, in addition to metabolism. Impairment of thyroid function in pregnant mothers may 

impact the fetus and result in such effects as changes in behavior, delayed development and 

decreased learning capability. Drinking water contaminated with perchlorate is the most likely way 

that perchlorate can be ingested. 

Recent studies conducted by the U.S. Department of Agriculture (Nov. 2004) and the 

Environmental Working Group (Apr. 2003) have detected perchlorate in samples of lettuce in 

California. Several other studies also detected perchlorate in milk samples taken from California and 

Texas. Additional studies of perchlorate uptake in food crops are currently being conducted by the 

U.S. Food and Drug Administration. 

Production of ammonium perchlorate first began in the United States in the mid- 1940s, primarily 

for use by the U.S. military. The most common uses for ammonium perchlorate are in explosives 

and rocket propellants, which have been widely used in military munitions items, such as mortars, 

grenades and flares and solid fuel rocket. Based on production data from two perchlorate 

manufacturers, it is estimated that 90 percent of perchlorate compounds are manufactured for use in 

defense activities and the aerospace industry. While occurring most frequently at domestic Air Force 

installations, ammonium perchlorate has been detected at Army and Navy sites too. The National 

Aeronautics and Space Administration (NASA) and Department of Energy (DOE) also have a small 

number of facilities with perchlorate (specific information on known perchlorate releases in the U.S. 

(XLS) (PDF, 7 pages, 515KB), as of September 23, 2004). In addition, ammonium perchlorate and 

the other perchlorate salts have been or are used in a wide range of applications, including 

pyrotechnics and fireworks, blasting agents, solid rocket fuel, matches, lubricating oils, nuclear 

reactors, air bags and certain types of fertilizers. Improper storage and/or disposal related to the 

uses mentioned above are the most typical route for perchlorate to enter into the environment. 

The EPA has been working with states, federal agencies, tribes, water suppliers and the private 

sector for several years to address perchlorate. In 1998, EPA released an Interim Assessment 

Guidance for Perchlorate (PDF, 4 pages, 224KB), which was then subject to peer review in 1999. 

The external review draft of the revised document "Perchlorate Environmental Contamination: 

Toxicological Review and Risk Characterization," (November, 2002) responds to those 

recommendations emanating from the peer review. 

The National Research Council of the National Academies published its technical review of the 

Health Implications of Perchlorate Ingestion in January 2005. From this review, EPA has 

established an official reference dose of 0.0007 mg/kg/day of perchlorate. This level is consistent 

with the recommended reference dose included in the National Academy of Science's report. A 

reference dose is a scientific estimate of a daily exposure level that is not expected to cause adverse 

health effects in humans. 

Thank you for your attention to this matter. As a practicing OB/Gyn, I am intimately concerned 

with your actions, on behalf of my patients and their children, both born and unborn. 

Response: See response to comment code 6120. 

Commenter Name: Richard F. Koch 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 623 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-0495 

EPA Comment ID: 19918 

EPA Comment Code: 6120 

 

Comment: This is a public comment on the matter of perchlorate content of drinking water. 

I urge that the standard be returned at least to the level permitted by today's standard. Better yet, a 

lower level should be mandated. 

Richard F. Koch dickkoch88@gmail.com 

Response: EPA does not regulate perchlorate in drinking water. See response to comment code 

6120. 

Commenter Name: Alison M. Russell 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0498 

EPA Comment ID: 19919 

EPA Comment Code: 6120 

 

Comment: As a private citizen who also works in the water field, I urge you to adopt a strict health 

standard for the regulation of perchlorate in drinking water. No water consumer should have to bear 

the furden of any of this chemical in their water. 

Thank you. 

Alison M. Russell 548 Sumner St. Santa Cruz, CA 95062 

Response: See response to comment code 6120. 

Commenter Name: Sister Mary Schmuck 

Commenter Organization: Sisters of Mercy 

EPA Document ID: EPA-HQ-OW-2008-0692-0499 

EPA Comment ID: 19920 

EPA Comment Code: 6120 

 

Comment: Letting perchlorate into water is very harmful to human health. 

Please prohibit it! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0501 

EPA Comment ID: 19921 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 624 of 1099

Comment: PERCHLORATES DAMAGE HEALTH IN ALL SENTIENT BEINGS!!! (THAT 

INCLUDES 'YOU' WAY PAST TIME TO INSTITUTE 'SAFE' LIMITS (I.E. NONE!) AS IT IS 

IN OUR WATER SUPPLY AND AFFECTS EVERYTHING, GRAZING GRASSES, FOODS, 

AND EVEN SHOWS UP IN OUR MILK PRODUCTS!!! 

MY UNDERSTANDING IS THAT THE EPA IS 'SUPPOSED' TO KEEP TRACK OF SAFE 

LIMITS OF BAD CHEMICALS AND MANDATE THAT THESE LIMITS ARE ACTUALLY 

ENFORCED. 

TIME TO DO YOUR JOB................ YOUR BAD, LACK OF CONTROL, IS KILLING ALL 

THINGS. 

Response: See response to comment code 6120. 

Commenter Name: Dr. L. Paull 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0502 

EPA Comment ID: 19922 

EPA Comment Code: 6120 

 

Comment: The current levels of perchlorate idrinking water are alarmingly dangerous. The EPA 

must regulateee the practices that are creating this level. 

Response: See response to comment code 6120. 

Commenter Name: L. Peles, M.D. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0503 

EPA Comment ID: 19923 

EPA Comment Code: 6120 

 

Comment: I think this is dangerous to our health. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Rhea Irvine 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0504 

EPA Comment ID: 19924 

EPA Comment Code: 6120 

 

Comment: It's more than a shame that citizens of many European countries are protected from 

substances that *may* endanger health than citizens of our own country. Among the many things 

that have declined under the current Republican administration, health and environmental 

protections --and the ethics of protecting or not protecting---rank high. Clean air and clean water 

should not be things that need to be debated or lobbied for. I urge you to set standards for 

perchlorate in water that are supported by the best scientific research. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 625 of 1099

Thank you, Rhea Irvine 

Response: See response to comment code 6120. 

Commenter Name: Kristen E. Cain 

Commenter Organization: FACOG 

EPA Document ID: EPA-HQ-OW-2008-0692-0505 

EPA Comment ID: 19925 

EPA Comment Code: 6120 

 

Comment: As a physician specializing in hormonal disorders, I cannot understand how this benefits 

any Americans. This compound may be linked to breast, ovarian, uterine, testicular and prostate 

cancers as well as infertility, birth defects, and is a documented offender in thyroid disease. Allowing 

an increase in levels of perchlorate in our tap water will increase disease, health care costs, usage of 

bottled water, energy costs for transport of bottled water and petroleum byproduct usage for the 

bottling of the water in a public attempt to avoid exposure to these pollutants. We need to be 

making our water safer! Kristen E. Cain, MD, FACOG 

Response: See response to comment code 6120. 

Commenter Name: J. Angelina 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0507

EPA Comment ID: 19927 

EPA Comment Code: 6120 

 

Comment: I believe this is dangerous to the public safety! 

Response: See response to comment code 6120. 

Commenter Name: Noel Rasor 

Commenter Organization: MUP 

EPA Document ID: EPA-HQ-OW-2008-0692-0508 

EPA Comment ID: 19928 

EPA Comment Code: 6120 

 

Comment: I urge the EPA to return to limit perchlorate levels in drinking water to its own 2002 

recommendations on what can be considered safe. This chemical is known to be harmful and 

exposure through water could pose a serious danger to public health. Sincerely, Noel Rasor, MUP 

Response: See response to comment code 6120. 

Commenter Name: J. McPeek 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0510 

EPA Comment ID: 19929 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 626 of 1099

Comment: Rocket fuel or anything like it in my tap water does nothing to enhance my health, and 

could damage it. Safe level my rear end! There is no such thing. 

Response: See response to comment code 6120. 

Commenter Name: Christine Lomaka 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0512 

EPA Comment ID: 19930 

EPA Comment Code: 6120 

 

Comment: Hi. I am a citizen of Portland, Maine. I have learned of your determination to not 

regulate perchlorate in our drinking water, though the amount of perchlorate in our water has been 

on the rise. It has been found to cause thyroid problems in pregnant women and in the youth of our 

country. These are among the very people this department has been created to protect. You should 

not support businesses at the expense of the people's and the environment's health. Do your job for 

the effects are lasting. 

Sincerely, Christine Lomaka CLonthroad@aol.com 76 Monument St. Portland, ME 04101 

Response: See response to comment code 6120. 

Commenter Name: C. Steinberg 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0513 

EPA Comment ID: 19931 

EPA Comment Code: 6120 

 

Comment: This is to support the positon of Physicians for Social Responsibility on the matter of 

minimum perchlorate residue in drinking water. I can't understand why EPA is backtracking on its 

minimum set years ago, proposing to more than double that minimum. In that major industrialized 

nations have perchlorate minima in drinking water even lower than the former EPA minimum, are 

we in this country reverting to the safety gauges more consistent with those in some nonindustrialized lands? The proposed elevation of the perchlorate minima for our drinking water is 

disgraceful. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0515 

EPA Comment ID: 19932 

EPA Comment Code: 6120 

 

Comment: The function of the EPA is to promote health for the citizens of the United States as 

well as the natural environment within the national borders. I am informed that the EPA's current 

acceptable minimum for perchlorate is 15 times the level that had been set in 2002. This is 

unacceptable, as scientific research has indicated the dangerous effects of perchlorate on pregnant 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 627 of 1099

women, new born and young children. I urge you to set a lower, mandatory safe minimum for 

perchlorate, because it should not be a part of our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: T. Udall 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0516 

EPA Comment ID: 19933 

EPA Comment Code: 6120 

 

Comment: Allowing perchlorate in drinking water is akin to murder, slow and torturous death, with 

or without healthcare. Corporations who think they are superior to life or that they have the right to 

destroy life without legal consequences must be regulated or there will come a time when there is no 

life left. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: H. Meyer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0517 

EPA Comment ID: 19934 

EPA Comment Code: 6120 

 

Comment: Perchlorate in our drinking water is harmful. Our limit should be none allowed. This 

chemical has been shown to be dangerous to infants and children causing thyroid disease, which 

may be a lifelong problem costing the individuals to suffer increased insurance fees, medication 

costs and problems with schooling. As a pediatrician I am appalled that the EPA has allowed an 

increase in the water levels of perchlorate a most dangerous substance. 

Response: See response to comment code 6120. 

Commenter Name: T. Johnson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0518 

EPA Comment ID: 19935 

EPA Comment Code: 6120 

 

Comment: This is found in Rocket Fuel people, ROCKET FUEL! Hello-this should be stopped 

NOW. Your actions affect the lives of people, their health and well being. 

This should not be allowed and the EPA has the power to stop this nonsense. 

So STOP allowing this in our drinking water! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 628 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0521 

EPA Comment ID: 19936 

EPA Comment Code: 6120 

 

Comment: No individual anywhere has been given the right to poison our drinking water and food. 

Any individual or agent who willfully poisons our water is a criminal. Do no poison our water with 

poisons, inorganic or viral. You are not protecting our health or the environment by poisoning our 

water with deadly toxins. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Joyce Paape 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0524 

EPA Comment ID: 19937 

EPA Comment Code: 6120 

 

Comment: Do not raise the amount of percolate in our drinking water- it would endanger more 

people than the present levels- especially pregnant wome & children!! Dr. Joyce Paape 

Response: Perchlorate is not regulated in drinking water. See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0527 

EPA Comment ID: 19939 

EPA Comment Code: 6120 

 

Comment: I believe that in this country we should be able to depend on our drinking water being 

safe, the air we breathe, the food we eat. What is the problem that you people cannot insure that 

that happens in this country? 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Jana Koth 

Commenter Organization: UNMC 

EPA Document ID: EPA-HQ-OW-2008-0692-0528 

EPA Comment ID: 19940 

EPA Comment Code: 6120 

 

Comment: Perchlorate is hazardous and needs to be eliminated. This is a dangerous public health 

concern. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: M. Huber 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 629 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-0529 

EPA Comment ID: 19941 

EPA Comment Code: 6120 

 

Comment: Drinking water is valuable and increasingly scarce. Please keep our free of chemicals. 

Response: See response to comment code 6120. 

Commenter Name: Rebecca Fletcher 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0530 

EPA Comment ID: 19942 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPAâ€TMs refusal to regulate Perchlorate under 

the Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

I'm very concerned about this. Please regulate the quantities of this dangerous chemical that are 

allowed to be present in drinking water. I know that perchlorate is a chemical in rocket fuel that has 

been linked to thyroid problems in pregnant women, newborns and young children. Not regulating 

this harmful chemical in our drinking water is totally unacceptable. Perchlorate is found in drinking 

water in 35 states, and according to the EPAâ€TMs own data, 16 million Americans are at risk of 

being exposed to this dangerous chemical. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0533 

EPA Comment ID: 19944 

EPA Comment Code: 6120 

 

Comment: Set a drinking water standard for Perchlorate. 

It's absurd for the EPA to refuse to set standards for this harmful pollutant in drinking water. 

It's the same as not regulating the amount of lead or mercury allowed in public drinking water. 

Do your job EPA. Protect the environment, protect the people. Set a rigorous standard for 

Perchlorate in drinking water! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0534 

EPA Comment ID: 19945 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 630 of 1099

 

Comment: I believe perchlorate is harmful to the public health. It causes thyroid problems in 

pregnant woman, newborns, and young children. Moreover, the safe limit for perchlorate is 15 times 

greater than what EPA declared in 2002. Too many people are potentialy exposed to this dangerous 

toxin. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0536 

EPA Comment ID: 19946 

EPA Comment Code: 6120 

 

Comment: why on earth would you add harmful chemicals to our drinking water!?!!! 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0540 

EPA Comment ID: 19947 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPA's refusal to regulate Perchlorate under the 

Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

The high level of perchlorate allowed in our current drinking water supply is shameful and unethical. 

Our government is the ONLY party that has the authority to regulate toxic industrial emissions in 

our environment, and yet our government continues to protect industry rather than people. 

Please keep the health of ordinary americans safe. Please pass legislation that requires cities and 

industries to clean up contaminated water to stricter standards. The technology exists today to do 

this! Why is this not happening? 

I urge you to create the strictest possible standards of perchlorate in our drinking water to keep 

future generations safe and healthy, in accordance with the Safe Drinking Water Act. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0541 

EPA Comment ID: 19948 

EPA Comment Code: 6120 

 

Comment: Allowing perchlorate in drinking water is a health risk! This decision is hazardous to the 

American population. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 631 of 1099

Response: See response to comment code 6120. 

Commenter Name: L. Abbott 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0542 

EPA Comment ID: 19949 

EPA Comment Code: 6120 

 

Comment: As perchlorate is detected in municipal water systems we need a strict standard to 

safeguard the public. We must always ere on the side of safety. 

Response: See response to comment code 6120. 

Commenter Name: Karen Ulring 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0543 

EPA Comment ID: 19950 

EPA Comment Code: 6120 

 

Comment: The EPA must set a standard that regulates the amount of perchlorate in our drinking 

water. It s well documented that this chemical in our water is dangerous, especially to pregnant 

women, and to peoples health in general. Please act to ensure the health of US citizens. 

Thank you, Karen Ulring 

Response: See response to comment code 6120. 

Commenter Name: C.M. Adams 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0545 

EPA Comment ID: 19951 

EPA Comment Code: 6120 

 

Comment: I am VERY sure that the United States needs very specific regulations on the amount of 

perchlorate allowed in public drinking water. Strict Regulations. 

The American public expect to be protected by the EPA and their government, not subject to 

policies that make it easy for pollution to remain in their 

water and polluters to go unpunished. We need to change jet fuel if it pollutes water sources. 

Do not let Americans down by allowing pollution that may cause Thyriod problems to remain in our 

water. There are at least 5 people i can name who have thryriod issues, many living in our tiny little 

town that is too small to have a post office. 

my husband was diagnosed 2 months ago. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 632 of 1099

This is a VERY serious issue. Do not allow corporations to continue as they are, just because it's 

easy to avoid rocking the boat. 

Thank you for your time and attention to this matter. 

Response: See response to comment code 6120. 

Commenter Name: Kenneth A. Popio 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0547 

EPA Comment ID: 19952 

EPA Comment Code: 6120 

 

Comment: I think making levels of allowable perchlorate in drinking water is hazardous to public 

health. 

Kenneth A. Popio 

Response: See response to comment code 6120. 

Commenter Name: M. O'Brien 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0548 

EPA Comment ID: 19953 

EPA Comment Code: 6120 

 

Comment: Perchlorate in their drinking water exposes 20 to 40 million Americans to the 

unnecessary risk of thyroid problems, according to independent analysis. Please see to it that the 

levels considered allowable are reduced significantly and monitored. Refusing to regulate the 

chemical ignores a significant harm to public health. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0549 

EPA Comment ID: 19954 

EPA Comment Code: 6120 

 

Comment: As a Registered Nurse, I am sickened by the lack of protection of our water supply 

when it comes to contaminants such as perchlorate. We know, beyond doubt, that there is no safe 

limit of this chemical in water. We must demand that our government do what is right and protect 

unsuspecting citizens from chemicals that are pervasive in our environment. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: T. C. Washburn 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 633 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-0550 

EPA Comment ID: 19955 

EPA Comment Code: 6120 

 

Comment: As a public health physician and a Pediatrician, I am very concerned about potential 

hazards of perchlorate in drinking water. There appears to be ample evidence of potential thyroid 

disease in newborns and young children. 

Please strongly consider setting a standard for maximal allowable perchlorate levels in drinking 

water. 

Thank you for your consideration. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0554 

EPA Comment ID: 19956 

EPA Comment Code: 6120 

 

Comment: please eliminate/ limit perchlorate from our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: D. Burton 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0555 

EPA Comment ID: 19957 

EPA Comment Code: 6120 

 

Comment: Please reevaluate your decision on perchlorate residue in drinking water. Our children 

need protection from a lifetime of such chemicals when possible. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0559 

EPA Comment ID: 19958 

EPA Comment Code: 6120 

 

Comment: Even if the perchlorate itself posed no apparent harm, which I believe it does, there 

have been no adequate studies of how iut interacts with othere chemicals or how sensitive 

individuals react to it. Additionally, how can the EPA or any group force American citizens to 

expose themselves to chemicals they believe they should not have in their systems? 

Response: This is not a comment, a response is not necessary. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 634 of 1099

Commenter Name: L. Garvey 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0571 

EPA Comment ID: 19959 

EPA Comment Code: 6120 

 

Comment: Nix Perchlorate! Do your job-Protect our water & health! You work for citizens, not 

industry! Discusted! 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0574 

EPA Comment ID: 19960 

EPA Comment Code: 6120 

 

Comment: Given a pattern in recent years of the FDA caving in to pressures from an 

administration that is militantly anitscience (and pro-corporate profits), I do not trust that a relaxing 

of regulation of perchlorate is in the public's best interest. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0575 

EPA Comment ID: 19961 

EPA Comment Code: 6120 

 

Comment: It is the mandate of the Environmental Protection Agency to protect U.S. residents 

from agents in our environment that are, or are potentially, harmful to our health. I thoroughly 

disagree with the proposal to stop regulating perchlorate in our water supply. 

Response: See response to comment code 6120. 

Commenter Name: David Myers 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0577 

EPA Comment ID: 19962 

EPA Comment Code: 6120 

 

Comment: Do not compromise the acceptable level of perchorate in drinking water. Drinking 

water standards should not exceed levels determined safe in your own study of 2002. Keep our 

water safe. 

Thank you. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 635 of 1099

David Myers 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0579 

EPA Comment ID: 19963 

EPA Comment Code: 6120 

 

Comment: It is not safe that perchlorate in the drinking water is fit to drink. 

Response: See response to comment code 6120. 

Commenter Name: Karl J. Volk 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0582 

EPA Comment ID: 19965 

EPA Comment Code: 6120 

 

Comment: I Karl J.Volk of 43 whittier blvd declare the EPA as not doing its job of protecing me 

against environmental issues in general and specifically against Perchlorate and "allowable " Levels . 

You are gettingmy Tax dollars andI want you to set limits on the prnicious fuel in the water 

aquivers. Shame on you God dam it 

Karl J.Volk 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0583 

EPA Comment ID: 19966 

EPA Comment Code: 6120 

 

Comment: Perchlorate is detrimental to human health. In particular, it disturbs thyroid functioning 

which in turn compromises immune functioning. It has been discovered to be present in the 

drinking water in at least 35 states. For these reasons, it must be declared hazardous and regulated. 

Response: See response to comment code 6120. 

Commenter Name: E.L. Blair 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0584 

EPA Comment ID: 19967 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 636 of 1099

Comment: I am writing to express my anger over the plan for the EPA not to regulate perchlorate 

in drinking water even though it has been found in water in 35 states. What part of Environmental 

PROTECTION do you not understand? 

I would like to see the EPA do what it is mandated to do by regulating perchlorate. This is nothing 

but a give-away to the weapons-making industries. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0586 

EPA Comment ID: 19969 

EPA Comment Code: 6120 

 

Comment: Is it not enough that the Senate Environment and Public Works Committee has 

endorsed legislation requiring the EPA to set a federal standard for perchlorate and to monitor 

levels of Perchlorate in tap water? The American public deserves to be able to drink their water with 

confidence that it's safe. If it isn't we may as well move to some third world country where the first 

question is, "Can I drink the water?" For shame, EPA! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0592 

EPA Comment ID: 19970 

EPA Comment Code: 6120 

 

Comment: Please stop poisoning the earth and all its inhabitants with your thirst for war profits. 

Stop building rockets and start saving lives. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Mary Sue Penn 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0601 

EPA Comment ID: 19972 

EPA Comment Code: 6120 

 

Comment: Please do not loosen standards for perchlorate. Our tap water is polluted enough! Go 

back at least to 2002 standards! We want pure, clean water. 

Thank you, Mary Sue Penn 

Response: See response to comment code 6120. 

Commenter Name: G. Grant 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 637 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0609 

EPA Comment ID: 19973 

EPA Comment Code: 6120 

 

Comment: I am writing to express my concern regarding the EPA's failure to regulate perchorate, 

as well as the proposed reference level. The citizens of the USA neeed their health protected from 

this toxin in our water. The health of our children need this protection. Thyroid disease has become 

too common and this autoimmune disease affects ones entire health. It is not a simple disease. It is 

not diaganosed and controlled easily as some seem to think. I request that the EPA take time for a 

complete and through evaluation, review the ever-changing scientific findings permitting the 

community time to evaluate and comment on the findings. Please do not rush a decision, one that 

could adversily affect the women and children of this great nation. 

Response: See response to comment code 6120. 

Commenter Name: L. Skipper 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0611 

EPA Comment ID: 19974 

EPA Comment Code: 6120 

 

Comment: I would like to comment regarding the EPA's failure to regulate perchlorate in the 

drinking water. It can cause thyroid problems. Five years ago, I was diagnosed as hypothyroid and 

my life has been ruined since then. The thought of this happening to millions of other people 

because the government has decided to look the other way in safeguarding our drinking water is 

outrageous! We depend on the EPA to protect the public and require the strongest standards for our 

drinking water. The public is looking for high standards for their drinking water without perchlorate 

in it. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0623 

EPA Comment ID: 19975 

EPA Comment Code: 6120 

 

Comment: Given the nature of the epidemic of thyroid dysfunction, and the increased health cost 

of treatment of such dysfunction, it is essential to set new, regulatory levels of Perchlorate in 

Drinking water to absolute lowest levels, with intention to eliminate sources of additional 

contamination in an urgent and immediate timely approach to safeguard further risk to public 

exposure. 

Further, all public schools must be equipped with appropriate filters on drinking water taps 

immediately. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 638 of 1099

Further, all public facilities = hospitals, restaurants, should be strongly advised to obtain, through 

tax relief measures, safe and reliable filters for all tap water sources. 

The public has the right to be protected. The cost of prevention far out weighs the cost of 

treatment. 

Response: See response to comment code 6120. 

Commenter Name: Margaret Baco 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0624 

EPA Comment ID: 19976 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPAâ€TMs refusal to regulate Perchlorate under 

the Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

Perchlorate is a chemical in rocket fuel that has been linked to thyroid problems in pregnant women, 

newborns and young children. Not regulating this harmful chemical in our drinking water is 

unacceptable. 

Perchlorate is found in drinking water in 35 states, and according to the EPAâ€TMs own data, 16 

million Americans are at risk of being exposed to this dangerous chemical. The cost of treating this 

epidemic of thyroid dysfunction is beyond estimate. 

Response: See response to comment code 6120. 

Commenter Name: Judith DiBiase Bennis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0631 

EPA Comment ID: 19981 

EPA Comment Code: 6120 

 

Comment: PLEASE ban perchlorate from our environment, especially water resources. The EPA 

must set very high regulation standards for this chemical that is poisoning our children, and in my 

case, grandchildren. 

Thank you. 

Juidth DiBiase Bennis 32 Summit Pass Medford, NJ 08055 

Response: See response to comment code 6120. 

Commenter Name: Carole 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0632 

EPA Comment ID: 19982 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 639 of 1099

 

Comment: Do not allow approve or in any way havepercholate in any waters that we ultimately will 

drink 

Response: See response to comment code 6120. 

Commenter Name: L.A. Coons 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0644 

EPA Comment ID: 19986 

EPA Comment Code: 6120 

 

Comment: Perchlorate in our drinking water is not safe! Do your job and protect the public. -Lisa 

A. Coons 

Response: See response to comment code 6120. 

Commenter Name: L. Segnitz 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0645 

EPA Comment ID: 19987 

EPA Comment Code: 6120 

 

Comment: as a physician, i ask you to please strongly consider regulating and monitoring 

perchlorate in tap water. there are significant health consequences of ingestion of this chemical. 

thank you. 

Response: See response to comment code 6120. 

Commenter Name: K. Peterson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0646 

EPA Comment ID: 19988 

EPA Comment Code: 6120 

 

Comment: I am appalled that the Environmental Protection Agency (EPA) has formally refused to 

set a drinking-water standard for perchlorate, a chemical in rocket fuel that has been linked to 

thyroid problems in pregnant women, newborns and young children. 

Response: See response to comment code 6120. 

Commenter Name: K. Peterson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0646 

EPA Comment ID: 19990 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 640 of 1099

Comment: Under this new standard, more than 16 million Americans are exposed to unsafe levels 

of perchlorate in their drinking water, and independent analysis shows anywhere from 20 to 40 

million Americans at risk. Perchlorate has been found in the drinking water in 35 states in the U.S. 

We should be working to protect our water and our environment; the fact that you are even 

considering raising these levels is unbelievable. 

We cannot continue to pollute our tap water. Besides the fact that this is bad for the environment, 

(the entity that your agency is supposed to protect), this is becoming social justice issue as well. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Luis Olmedo Vélez 

Commenter Organization: omité Cívico del Valle, Inc. 

EPA Document ID: EPA-HQ-OW-2008-0692-0652 

EPA Comment ID: 19993 

EPA Comment Code: 6120 

 

Comment: Luis Olmedo Vélez Executive Director Comité Cívico del Valle, Inc. 699 E Street 

Brawley, CA 92227 October 24, 2008 

Eric Burneson Office of Ground Water and Drinking Water Standards and Risk Management U.S. 

Environmental Protection Agency 

 Dear Sir: 

We are concerned that the EPA’s failure to regulate perchlorate, as well as its unprotective proposed 

health reference level, will adversely affect the health and development of hundreds of thousands, 

perhaps millions of American children. In addition, expecting mothers will run the risk of 

permanently damaging the development of their unborn children. Not only will unborn children be 

affected, but the elderly population as well. Elderly people with a history of medical conditions will 

have a difficult time fighting off the effects that perchlorate may have. 

Response: See response to comment code 6120. 

Commenter Name: Luis Olmedo Vélez 

Commenter Organization: omité Cívico del Valle, Inc. 

EPA Document ID: EPA-HQ-OW-2008-0692-0652 

EPA Comment ID: 19994 

EPA Comment Code: 6120 

 

Comment: Imperial Valley undergoes several environmental risks: The air is unclean. Pesticides are 

used regularly where people may come in contact with it. EPA’s inability to contain perchlorate will 

only add to the already unstable environment in the Imperial Valley. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 641 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-0159 

EPA Comment ID: 20015 

EPA Comment Code: 6120 

 

Comment: Please don't let more perchlorate into the drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #4 - Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-0687 

EPA Comment ID: 20016 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

I urge you to set a drinking water standard for perchlorate that will protect pregnant women and 

babies nationwide. Perchlorate poses a risk for pregnant women, newborns and young children by 

interfering with thyroid hormone, which is critical for optimal development of the brain and nervous 

system. Perchlorate is found in drinking water in at least 26 states, and 20-40 million people could be 

exposed to this chemical. 

Several states have set drinking water standards or guidelines for this chemical, but these standards 

vary widely, so it is critical for the EPA to set a national standard that is based on the best available 

science and that will protect public health. The EPA's own staff scientists have determined that your 

decision not to regulate perchlorate places some infants and young children above safe levels of 

exposure. The EPA's current draft scientific analysis should undergo independent scientific peer 

review and should be used as the basis for the regulation. 

Response: The Agency believes that further review by the National Research Council would 

unnecessarily delay regulatory decision making for perchlorate. Therefore, EPA is not, at present, 

planning to request additional NRC review of issues related to perchlorate. Instead, EPA is issued a 

notice in August of 2009 seeking comments on a broad range of alternative approaches to the 

interpretation of the scientific data relevant to a regulatory determination for perchlorate in drinking 

water. 

EPA has determined to regulate perchlorate in drinking water. See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #4 - Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-0687 

EPA Comment ID: 20018 

EPA Comment Code: 6120 

 

Comment: Again, I urge you to reverse your decision and to set a national drinking water standard 

for perchlorate. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 642 of 1099

Response: See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #5 - Clean Water Fund/Clean Water Action 

EPA Document ID: EPA-HQ-OW-2008-0692-0689 

EPA Comment ID: 20019 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

* perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; 

* a national primary drinking water regulation would provide a meaningful opportunity to protect 

public health. 

Additional Facts 

* Perchlorate is a harmful chemical used in rocket fuel, flares, and explosives. 

* Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development and metabolism. 

* Developing fetuses, infants and children with thyroid impairment may suffer mental retardation, 

loss of hearing and speech or deficits in motor skills. 

* EPA agrees that perchlorate has been found in 395 sites in 37 states, including 153 public water 

systems serving over 20 million people. Some estimates are even higher. 

Response: See response to comment code 6120. 

Commenter Name: Pete McHugh 

Commenter Organization: Santa Clara County Board of Supervisors 

EPA Document ID: EPA-HQ-OW-2008-0692-0681 

EPA Comment ID: 20020 

EPA Comment Code: 6120 

 

Comment: October 15, 2008 

Stephen L. Johnson, Administrator Environmental Protection Agency - Mail Code 2822T 1200 

Pennsylvania Avenue, N .W. Washington, D.C. 20460 

Re: Docket ID No. EPA-HQ-OW-2008-0692 

Dear Mr. Johnson: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 643 of 1099

The Santa Clara County Board of Supervisors does not agree with the preliminary determination of 

the Environmental Protection Agency (EPA) to not regulate perchlorate in drinking water at a 

national level. 

Response: See response to comment code 6120. 

Commenter Name: Pete McHugh 

Commenter Organization: Santa Clara County Board of Supervisors 

EPA Document ID: EPA-HQ-OW-2008-0692-0681 

EPA Comment ID: 20022 

EPA Comment Code: 6120 

 

Comment: In September 2007, the State of California adopted a regulation to establish a maximum 

contaminant level (MCL) of 6 micrograms per liter for perchlorate in drinking water. However, a 

national standard is critical to safeguard water supplies throughout the nation and provide a baseline 

for enforcement by the EPA. 

Community health is one of our Board's highest priorities. The protection of our residents through 

an enforceable drinking water standard for perchlorate is of paramount concern. It is for these 

reasons, the Santa Clara County Board of Supervisors urges your reconsideration of the need for a 

national perchlorate standard, and requests the EPA to protect public health by setting a Federal 

drinking water standard at or below the 6 micrograms per liter established in California. 

Sincerely, 

Pete McHugh Chair, Board of Supervisors 

c: Santa Clara County Board of Supervisors Peter Kutras, Jr., County Executive Jerry Klepner, 

BKSH and Associate s Santa Clara County Congressional Delegation 

COUNTY GOVERNMENT CENTER 70 WEST HEDDING STREET SAN JOSE, 

CALIFORNIA 95110 

TEL: (4O8) 299-5030 FAX: (4O8) 298-6637 

Response: See response to comment code 6120. 

Commenter Name: P. Grieman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0683 

EPA Comment ID: 20024 

EPA Comment Code: 6120 

 

Comment: I'm responding as an individual, not an organization, to say that I am appalled that the 

EPA is refusing to regulate Perchlorate under the Safe Water Drinking Act (Docket ID EPA-HQOW-2008-0692). 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 644 of 1099

As is recognized in many countries outside the United States, perchlorate is a harmful chemical in 

rocket fuel that has been linked to thyroid problems in pregnant women, newborns and young 

children. Perchlorate is found in drinking water in 35 states, and according to the EPA's own data, 

16 million Americans are at risk of being exposed to this dangerous chemical. 

Not regulating this harmful chemical in our drinking water is unacceptable. I urge you to set a 

standard to protect Americans' health in accordance with the Safe Drinking Water Act. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0688 

EPA Comment ID: 20025 

EPA Comment Code: 6120 

 

Comment: Please regulate Perchlorate 

Response: See response to comment code 6120. 

Commenter Name: Brittni 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0690 

EPA Comment ID: 20026 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; a national primary drinking water regulation would provide a meaningful 

opportunity to protect public health. 

Please still regulate this. Thank you! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0691 

EPA Comment ID: 20027 

EPA Comment Code: 6120 

 

Comment: reverse this decision. 

Response: See response to comment code 6120. 

Commenter Name: Karen Parmett 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 645 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0693 

EPA Comment ID: 20028 

EPA Comment Code: 6120 

 

Comment: We must keep rocket fuel and related waste streams out of our public drinking water. 

Please keep perchlorate out of our drinking water! 

yours sincerely, 

Karen Parmett 86 Clark St. Belmont MA 02478 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0694 

EPA Comment ID: 20029 

EPA Comment Code: 6120 

 

Comment: I request that the U.S. Environmental Protection Agency set a regulation for perchlorate 

in drinking water. 

I have been concerned for some time about contamination in our water supply and have researched 

and now use water purification for my personal home drinking, cooking and bathing 

water.Perchlorate is one of the contaminants I am concerned about and try to control in our water 

supply. 

I believe that perchlorate contamination is a nationwide problem and poses a general health risk if 

not regulated and monitored. 

A national primary water regulation should include strict levels of perchlorate contamination that 

would protect the public health. 

Please reconsider any decisions that reduce the control of perchlorate in our water supply. 

Response: See response to comment code 6120. 

Commenter Name: J. Brundage 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0696 

EPA Comment ID: 20030 

EPA Comment Code: 6120 

 

Comment: Please regulate perchlorate in water. People drink that stuff! 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 646 of 1099

Commenter Name: Tricia Telesco 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0697 

EPA Comment ID: 20031 

EPA Comment Code: 6120 

 

Comment: Perchlorate is a very harmful chemical and once ingested, even in minute amounts, will 

adversely effect the public's health and safety. I strongly urge the EPA reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Tricia Telesco 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0699 

EPA Comment ID: 20032 

EPA Comment Code: 6120 

 

Comment: Keep perchlorate out of our drinking water 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0700 

EPA Comment ID: 20033 

EPA Comment Code: 6120 

 

Comment: Please keep our drinking safe beyond any common sense doubt and regulate 

perchlorates. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0701 

EPA Comment ID: 20034 

EPA Comment Code: 6120 

 

Comment: How can the EPA not want to regulate perchlorate? That's a rhetorical question - it's 

pretty blatantly clear someone is being paid off, again. 

Whoever is making these decisions needs to go, so that the EPA can do its job. I for one will 

support any effort by the EPA employees to oust the corrupt political appointees killing us for 

money. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 647 of 1099

Response: See response to comment code 6120. 

Commenter Name: L.S. Johnson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0705 

EPA Comment ID: 20035 

EPA Comment Code: 6120 

 

Comment: Please reverse your preliminary determination on setting a regulation for perchlorate in 

drinking water. Perchlorate should be regulated. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0708 

EPA Comment ID: 20036 

EPA Comment Code: 6120 

 

Comment: Please regulate perchlorate. It can damage a person's thyroid gland. We have enough 

medical expenses in this country. 

Response: See response to comment code 6120. 

Commenter Name: Carol Klingsmith 

Commenter Organization: Workout for Wellness 

EPA Document ID: EPA-HQ-OW-2008-0692-0709 

EPA Comment ID: 20037 

EPA Comment Code: 6120 

 

Comment: I feel it is imperative to keep our drinking water clean and safe. Please no Perchlorate in 

the water. 

Response: See response to comment code 6120. 

Commenter Name: S. Strohmeyer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0710 

EPA Comment ID: 20038 

EPA Comment Code: 6120 

 

Comment: Why are you even considering this? Our government should be here to defend us from 

outside danger, but this is just one more way to hurt our people and our beautiful country. The EPA 

is supposed to protect us from harm not kill us from the inside. 

Response: See response to comment code 6120. 

Commenter Name: M. Fiorini 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 648 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0712 

EPA Comment ID: 20039 

EPA Comment Code: 6120 

 

Comment: Perchlorate, at any level, should not be allowed into our drinking water. It is a shame 

that you have to hold a public response to determine that we should not be drinking perchlorate. 

There are many scientific reports that determine perchlorate is unsafe to drink and one does not 

have to be a rocket scientist to know that rocket fuel is bad for humans and is also bad for all other 

living creatures. It should not be allowed in our drinking water, regardless of the cost of removal. I 

know the government has spent more money on less worthwhile causes. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0715 

EPA Comment ID: 20040 

EPA Comment Code: 6120 

 

Comment: I urge the Environmental Protection agency to do whatever it can to protect the 

drinking water supply in this country. It remains a highly vulnerable resource, critical to the health 

and well being of our entire population. Please work to regulate the effects of perchlorate in the 

water supply. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0717 

EPA Comment ID: 20041 

EPA Comment Code: 6120 

 

Comment: It is imperative that the EPA regulate perchlorate (an ingredient of rocket fuel) and 

insist that it be kept out of our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0721 

EPA Comment ID: 20042 

EPA Comment Code: 6120 

 

Comment: Perchlorate is Poison. Vote NO on Docket ID: EPA-HQ-OW-2008-0692 Drinking 

Water: Preliminary Regulatory Determination on Perchlorate Would you want to drink or bathe in 

this? 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 649 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0722 

EPA Comment ID: 20043 

EPA Comment Code: 6120 

 

Comment: please do not allow perchlorate in the drinking water. If I wanted that in my water I 

would go out and get it. Try to keep our drinking water as pure as possible. Thank you from 

someone who drinks a lot of water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0725 

EPA Comment ID: 20044 

EPA Comment Code: 6120 

 

Comment: Please reconsider your position on percholate, and set standards for it exclusion from 

drinking water. 

Response: See response to comment code 6120. 

Commenter Name: J. Rosalia 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0726 

EPA Comment ID: 20045 

EPA Comment Code: 6120 

 

Comment: Keep PERCHLORATE OUT of the water. It is INSANE to even consider allowing it 

in. 

Response: See response to comment code 6120. 

Commenter Name: Molly Lindner 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0732 

EPA Comment ID: 20046 

EPA Comment Code: 6120 

 

Comment: The drinking water in my locale, North Canton, Ohio, is still not drinkable, in my 

opinion, without filtering because it has chlorine in it and smells, tastes awful. Please regulate 

Perchlorate and order local water control officers to purge this chemical from our drinking water. 

Thank you. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 650 of 1099

Dr. Molly Lindner 

Response: See response to comment code 6120. 

Commenter Name: Luis Olmedo VÃ©lez 

Commenter Organization: ComitÃ© CÃvico del Valle, Inc., Center for Health Education, 

Prevention and Advocacy 

EPA Document ID: EPA-HQ-OW-2008-0692-0736 

EPA Comment ID: 20047 

EPA Comment Code: 6120 

 

Comment: Mr. Burneson, Tell EPA to extend the time comment period to 90 days. Thank you. 

Luis Olmedo VÃ©lez Executive Director ComitÃ© CÃvico del Valle, Inc. 699 E Street Brawley, 

CA 92227 October 24, 2008 

Eric Burneson Office of Ground Water and Drinking Water Standards and Risk Management U.S. 

Environmental Protection Agency 

 Dear Sir: 

We are concerned that the EPAâ€TMs failure to regulate perchlorate, as well as its unprotective 

proposed health reference level, will adversely affect the health and development of hundreds of 

thousands, perhaps millions of American children. In addition, expecting mothers will run the risk 

of permanently damaging the development of their unborn children. Not only will unborn children 

be affected, but the elderly population as well. Elderly people with a history of medical conditions 

will have a difficult time fighting off the effects that perchlorate may have. 

Imperial Valley undergoes several environmental risks: The air is unclean. Pesticides are used 

regularly where people may come in contact with it. EPAâ€TMs inability to contain perchlorate will 

only add to the already unstable environment in the Imperial Valley. 

Response: EPA announced on October 10, 2008, its preliminary regulatory determination that a 

national primary drinking water regulation for perchlorate would not present "a meaningful 

opportunity for health risk reduction for persons served by public water systems." In response to 

requests from several stakeholders, EPA reopened the public comment period for an additional 15 

days. Regarding EPA's determination to regulate perchlorate in drinking water, See response to 

comment code 6120. 

Commenter Name: D. Kaufer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0738 

EPA Comment ID: 20049 

EPA Comment Code: 6120 

 

Comment: Please do not allow percholate in our drinking water 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 651 of 1099

Response: See response to comment code 6120. 

Commenter Name: G. Hansen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0741 

EPA Comment ID: 20050 

EPA Comment Code: 6120 

 

Comment: The U.S. Environmental Protection Agency should reverse its preliminary determination 

on setting a regulation for perchlorate in drinking water. 

There is no reason this country should allow these types of chemicals in our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0744 

EPA Comment ID: 20051 

EPA Comment Code: 6120 

 

Comment: Hello, It has come to my attention that the EPA has made a preliminary decision NOT 

to regulate perchlorate, a rocket fuel, with respect to contamination of drinking water. Considering 

both the divergent and grave effects to humans upon exposure to this chemical as well as recent 

studies showing that the chemical is dangerous at lower levels than previous thought, it is outrageous 

that the EPA would make such a poor decision. Please reconsider in favor of regulating perchlorate 

for the sake of our health and especially the health of our babies and developing fetuses. 

Response: See response to comment code 6120. 

Commenter Name: K. Minissale 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0746 

EPA Comment ID: 20052 

EPA Comment Code: 6120 

 

Comment: Even though percholate is only found to affect a very small percentage of the 

population (by geographical location), a national health standard should be set in light of the fact 

that all people, even minority groups, deserve protection of their basic health condidtions and that 

having a national standard in place can only benefit others in the future should greater affected areas 

be discovered. 

Response: See response to comment code 6120. 

Commenter Name: R. Cubberly 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0747 

EPA Comment ID: 20053 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 652 of 1099

EPA Comment Code: 6120 

 

Comment: Keep Perchlorate out of our drinking water!! Please reverse your decision! 

Response: See response to comment code 6120. 

Commenter Name: V. Hollen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0748 

EPA Comment ID: 20054 

EPA Comment Code: 6120 

 

Comment: I urge the EPA to reverse its preliminary determination on setting a regulation for 

perchlorate in drinking water. It has several potential health consequences: impaired thyroid gland, 

child developmental impairment including mental retardation, deficits in motor skills... Please be the 

clarion to declare the the US government is going to protect its citizens from contaminated water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0749 

EPA Comment ID: 20055 

EPA Comment Code: 6120 

 

Comment: Water is our most precious resource. I think the EPA needs to rethink its decision and 

start better protecting our water supply by regulating the amount of percholate in our drinking 

water. We should all be comfortable drinking from the tap in our homes, not constantly worrying 

about what contaminate has now found its way into our wells and water supplies. No one trusts the 

water as can be seen by the rise in purchasing of bottled water. It's your job to keep our water safe. 

Perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought. A national primary drinking water regulation would provide a meaningful 

opportunity to protect public health. 

Response: See response to comment code 6120. 

Commenter Name: J. Traweek 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0752 

EPA Comment ID: 20057 

EPA Comment Code: 6120 

 

Comment: We are very concerned that the EPA will not be exercising its regulatory authority and 

the statutory purpose for its existence if the EPA does not take the needed steps to safeguard 

America's water quality by regulating the contamination of our water with perchlorate. Thank you 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 653 of 1099

Commenter Name: K. McDonald 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0754 

EPA Comment ID: 20058 

EPA Comment Code: 6120 

 

Comment: I strongly urge this agency to reconsider it's decision to allow unlimited polution of our 

drinking water supplies with Perchlorate. Remember you and your family is drinking this water too. 

Response: See response to comment code 6120. 

Commenter Name: Raymon A. Baldoni 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0755 

EPA Comment ID: 20059 

EPA Comment Code: 6120 

 

Comment: I have survery several dozen people in my neighberhood and 100% are against the 

EPA's tentative decision not to regulate perchlorate in drinking water. This decision is not in the 

best interests of the public and appears to be complete fiscally motivated. Our health and the health 

of our children is not negotiable and should not be relaxed to "reasonable care" standards. The EPA 

needs to be aggressive in setting all air and water standards to a best practice standard and deamnd 

funding to enable the agressive enforcement of these standards. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0757 

EPA Comment ID: 20060 

EPA Comment Code: 6120 

 

Comment: I URGE YOU TO RECONSIDER YOUR DECISION NOT TO REGULATE 

PERCHLORATE IN DRINKING WATER. I AM CONCERNED ABOUT THE HEALTH 

IMPACTS, PARTICULARLY ON INFANTS AND CHILDREN. PLEASE TAKE ACTION TO 

PROTECT OUR WATERS AND THE PUBLIC HEALTH. THANK YOU. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0761 

EPA Comment ID: 20061 

EPA Comment Code: 6120 

 

Comment: ALL chemicals that can get into our drinking water should be monitored and regulated. 

I am curious as to why you would NOT monitor and regulate such things. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 654 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0762 

EPA Comment ID: 20062 

EPA Comment Code: 6120 

 

Comment: Please continue to regulate Perchlorate and all the chemicals which may be harmful in 

our drinking water. I urge you to reverse your preliminary decision on this. 

Response: Perchlorate is not regulated in drinking water. See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0767 

EPA Comment ID: 20063 

EPA Comment Code: 6120 

 

Comment: You must work to regulate rocket fuel in our drinking water. This is not optional, we 

need all the safeguards in place to make sure our safe drinking water, which is becoming ever more 

precious and scarce, remains so. It could be improved in so many ways, but certainly this is an easy 

one to regulate. Thank you! 

Response: See response to comment code 6120. 

Commenter Name: G. E. Andrews 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0769 

EPA Comment ID: 20064 

EPA Comment Code: 6120 

 

Comment: Perchlorate in our drinking water is unacceptable. We need your leadership to make the 

right decision immediately to protect human health. 

Response: See response to comment code 6120. 

Commenter Name: Roger N. Carlsten 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0770 

EPA Comment ID: 20065 

EPA Comment Code: 6120 

 

Comment: I strongly urged the EPA to take any action necessary to eliminate percholates from our 

national drinking water. Not just because I already suffer from hypothyroidism, but how it adversely 

affects all citizens, especially developing fetuses and young children. 

Sincerely, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 655 of 1099

Roger N. Carlsten, D.D.S. 

Response: See response to comment code 6120. 

Commenter Name: Anita Burns 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0771 

EPA Comment ID: 20066 

EPA Comment Code: 6120 

 

Comment: What is it that makes you think I want to have water with this chemical in it! There 

should be criminal action taken to those that disposed this chemical into the water system & they 

should have to pay to clean up this mess!. Our health is more important than letting this chemical 

stay in the water. I am strongly opposed to having this chemical in the water!!!!! Perchlorate is a 

harmful chemical used in rocket fuel, flares, and explosives. Perchlorate, even in small amounts, can 

impair the thyroid gland, which controls growth, development and metabolism. Developing fetuses, 

infants and children with thyroid impairment may suffer mental retardation, loss of hearing and 

speech or deficits in motor skills. Anita Burns ...bosburns@wowway.com 

Response: See response to comment code 6120. 

Commenter Name: H. Passas 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0772 

EPA Comment ID: 20067 

EPA Comment Code: 6120 

 

Comment: I wish to urge the EPA to reconsider the preliminary decision not to regulate 

perchlorate in drinking water. This is a harmful substance that can damage the thyroid, thus 

affecting growth, development and metabolism at minute exposure levels, especially in babies in 

small children. Perchlorate has already been found in the drinking water consumed by millions of 

US citizens. I think it is unconscionable for the government agency that has the obligation to protect 

the environment which sustains us all to fail in its task of regulating dangerous substances! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0774 

EPA Comment ID: 20068 

EPA Comment Code: 6120 

 

Comment: Please protect our health and well-being through the regulation of perchlorate in 

drinking water. It is a lethal contaminant not for consumption. Your responsibility is to protect the 

environment, not damage it and its inhabitants. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 656 of 1099

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0776 

EPA Comment ID: 20069 

EPA Comment Code: 6120 

 

Comment: It is the responsibility of the EPA to regulate perchlorate in drinking water. I urge you, 

the U.S. Environmental Protection Agency, to reverse your preliminary determination on setting a 

regulation for perchlorate in drinking water. Here are a few facts on perchlorate: 

* perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0776 

EPA Comment ID: 20071 

EPA Comment Code: 6120 

 

Comment: I know perchlorate is found in drinking water and drinking water source areas because I 

worked on the assessment and remediation of contaminated and potentially contaminated properties 

in New England that had perchlorate. The people of the US depend on you to protect their drinking 

water. You must take the lead in establishing and enforcing a drinking water perchlorate regulation. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0778 

EPA Comment ID: 20076 

EPA Comment Code: 6120 

 

Comment: Keep perchlorate out of our drinking water supply. 

Response: See response to comment code 6120. 

Commenter Name: Richard 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0780 

EPA Comment ID: 20077 

EPA Comment Code: 6120 

 

Comment: The regulation or perchlorates in drinking water should be established as soon as 

possible. this harmful chemical poses a threat to humans and should be dealt with accordingly.. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 657 of 1099

thank you. Richard 

Response: See response to comment code 6120. 

Commenter Name: Linda D. Hrushanyk 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0782 

EPA Comment ID: 20078 

EPA Comment Code: 6120 

 

Comment: After reading some of the facts on perchlorate and the potential health problems the 

chemical can cause, don't you think regulating the amount of perchlorate would prevent some health 

problems? 

linda d. hrushanyk 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0783 

EPA Comment ID: 20079 

EPA Comment Code: 6120 

 

Comment: Keep ariplane fuel out of our water, perchlorate does not belong in our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0784 

EPA Comment ID: 20080 

EPA Comment Code: 6120 

 

Comment: Please do not lower the standards for clean water. As a member of the public I would 

prefer my drinking water to be free of rocket fuel. Thank you 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0785 

EPA Comment ID: 20081 

EPA Comment Code: 6120 

 

Comment: Please regulate perchlorate in drinking water. I am sure the science exists to filter it so 

we should use it. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 658 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0787 

EPA Comment ID: 20082 

EPA Comment Code: 6120 

 

Comment: Regulate Perchlorate in our drinking water! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0788 

EPA Comment ID: 20083 

EPA Comment Code: 6120 

 

Comment: Perchlorate has leaked into our water supplies everywhere, though particularly in the 

western and southwestern United States. It has turned up in our lettuce! 

Ingredients of rocket fuel do not belong in our water. And if our tap water isn't clean, we're paving 

the way for the privatization of water, which means only the rich people will have water and the rest 

of us will have to fight each other for it. 

Keep the water clean and get perchlorate out of our water. This one's a no- brainer. 

Response: See response to comment code 6120. 

Commenter Name: Mary Green 

Commenter Organization: Eleventh Street Family Health Service Center 

EPA Document ID: EPA-HQ-OW-2008-0692-0789 

EPA Comment ID: 20084 

EPA Comment Code: 6120 

 

Comment: q-OW-2008-0068To: Councilman Curtis J. Jones 4th District Room 404 Phila. PA 

19107 

In regard to contamination of our water and the water regulations please support identified as Water 

regulations Docket ID No. EPA-HQ-OW-2008-0068. The EPA will make final determinations on 

this health advisory for percholorate of contamination into our water supply and the regulation of it. 

Please consider looking inot this. thank you. Mary Green MSN, RN . Eleventh Street Family Health 

Service Center 850 11th Street Phila. PA 19123 Attachments [see PDF of Docket ID EPA-HQOW-2008-0692-0789] 

EPA-HQ-OW-2008-0692-0789.1 Comment attachment submitted by Curtis J. Jones, Philadelphia 

City Council 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 659 of 1099

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0790 

EPA Comment ID: 20085 

EPA Comment Code: 6120 

 

Comment: We don't need rocket fuel in our drinking water. If you are planning to join Bush and 

company on a remote island after looting the treasury, you might think that you're safe from it, but 

you're not. And if you're an alcoholic that denies being in a water-based environment, clear your 

thinking for a moment and figure out that everything that you eat has water in it. Tap water, for the 

most part. No, even living on bottled water won't get you away from perchlorate, as most plastic 

bottles have perchlorate in them. It won't do anyone good to relax rules that are there to protect all 

of us. Just don't change the rules! 

Response: See response to comment code 6120. 

Commenter Name: L. Thorp 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0791 

EPA Comment ID: 20086 

EPA Comment Code: 6120 

 

Comment: Please regulate Perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0792 

EPA Comment ID: 20087 

EPA Comment Code: 6120 

 

Comment: Please make sure that the standard for drinking water in the USA is one that does not 

allow for perchlorate. Thank you 

Response: See response to comment code 6120. 

Commenter Name: C. Smith 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0798 

EPA Comment ID: 20088 

EPA Comment Code: 6120 

 

Comment: There is no reason or excuse not to regulate Perchlorate that affects our drinking water. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 660 of 1099

Commenter Name: Pamela Love Koepf 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0801 

EPA Comment ID: 20089 

EPA Comment Code: 6120 

 

Comment: Please do not allow our water to be unregulated for Perchlorate. We need any and all 

help to monitor all innappropriate invasives in our drinking and open water supply. If you guys don't 

do it, who will? Please reverse this important decision for the sake of all of us! 

Pamela Love Koepf Bellevue, WA 

Response: See response to comment code 6120. 

Commenter Name: C. P. Gabelman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0804 

EPA Comment ID: 20090 

EPA Comment Code: 6120 

 

Comment: I believe the mandate of the EPA is to protect our nation's citizens - not our nation's 

corporations. So please, get out of political mode and get back into protection mode and start 

carrying out your mandate to provide a safe environment for me, my children, my grandchildren and 

beyond. Perchlorate has no business being in our drinking water supply. Please quit waiting for a 

crisis to develop before you have the backbone to do your job. 

Response: See response to comment code 6120. 

Commenter Name: C. Springer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0805 

EPA Comment ID: 20091 

EPA Comment Code: 6120 

 

Comment: We don't know how to do it. We trust that drinking water and water that is home to 

aquatic animals will be protected from rocket fuel. thank you for your work. 

Response: See response to comment code 6120. 

Commenter Name: Tana Moore 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0807 

EPA Comment ID: 20092 

EPA Comment Code: 6120 

 

Comment: To the U.S. Environmental Protection Agency - please reverse your preliminary 

determination on regulating perchlorate in drinking water. This is a substance known to cause 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 661 of 1099

thyroid damage. The public and wildlife need protection from such substances in our water. Thank 

you. 

Tana Moore 21472 Wallace Drive Southfield MI 48075 

Response: Please See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0811 

EPA Comment ID: 20093 

EPA Comment Code: 6120 

 

Comment: No Perchlorate in the drinking water, please! 

Response: See response to comment code 6120. 

Commenter Name: R. Stevenson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0812 

EPA Comment ID: 20094 

EPA Comment Code: 6120 

 

Comment: Please don't let our drinking water be contaminated by Perchlorate. Clean water is 

becoming more and more rare and you are risking the future by allowing this chemical to enter our 

lakes and streams. Please ask yourself if you would be okay with letting your children or grand 

children consume water or fish in a stream with Perchlorate in it. Thank you for your consideration 

in this matter. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0813 

EPA Comment ID: 20095 

EPA Comment Code: 6120 

 

Comment: Please regulate perchlorate. It's meant for rockets not people. 

Response: See response to comment code 6120. 

Commenter Name: D. and A. M. Wahl Edwards 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0816 

EPA Comment ID: 20096 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 662 of 1099

Comment: Keep perchlorate out of our water supply via regulation. Please protect our future by 

protecting the fetuses carried in our mothers' wombs. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0819 

EPA Comment ID: 20097 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. We need to maintain good 

quality drinking water and regulate poisons such as this. Please continue to regulate this poison for 

the welfare of US citizens. 

Response: Perchlorate is not regulated in drinking water. See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0822 

EPA Comment ID: 20098 

EPA Comment Code: 6120 

 

Comment: Please regulate amounts of perchlorate in America's drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0823 

EPA Comment ID: 20099 

EPA Comment Code: 6120 

 

Comment: There is no reason to believe perchlorate is harmless.Since there is more evidence it is 

harmful to our health does it not make sense for the EPA to be proactive in regulating it rather than 

risking our health? Scientific studies that are without influence of any industry need to become the 

standard so that your agency can function with some degree of integrity.The US was once a leader in 

environmental issues and we need to get back to that level. 

Response: See response to comment code 6120. 

Commenter Name: Adam Nation 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0825 

EPA Comment ID: 20100 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 663 of 1099

Comment: Dear Sir/Madam: 

It has come to my attention that the EPA, under the leadership of President Bush, has refused to 

regulate the presence of perchlorate in American drinking water. I urge the Agency to reconsider 

this decision. Perchlorate is a chemical that has been linked to numerous deleterious health effects in 

humans (and other animals)-- including serious changes in the thyroid gland, and a potential impact 

on cognition and normal fetal development. 

For these reasons, I urge the EPA to regulate perchlorate very strictly. 

Cordially, 

Adam Nation Pittsburgh, PA 

Response: See response to comment code 6120. 

Commenter Name: Dina C. Greenway 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0827 

EPA Comment ID: 20101 

EPA Comment Code: 6120 

 

Comment: As we look hopefully toward a new attitude about our environment, we look to the 

EPA to set sound policy. Father Bush is waving goodbye. And the American people look forward to 

greater ease as you work to protect our health and give a second chance to an environment now on 

life support. 

Let your first act be to reverse to research and regulate for PERCHLORATE in our drinking water. 

I thank you, and do a landslide majority of your constituents. 

:) :) :) :) dina 

Response: See response to comment code 6120. 

Commenter Name: D. Toolanen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0828 

EPA Comment ID: 20102 

EPA Comment Code: 6120 

 

Comment: Please forbid any perchlorates to enter any water systems. The costs and suffering of it 

are carried by the innocent victims, people, animals, insects, birds, whose physiology will be 

negatively impacted by these unnatural and toxic chemicals. 

Response: See response to comment code 6120. 

Commenter Name: Nikki Black 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 664 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0829 

EPA Comment ID: 20103 

EPA Comment Code: 6120 

 

Comment: Every day I seem to hear about friends and loved ones dealing with often fatal illnesses 

or struggling with conditions that come from our polluted environment. It is extremely disturbing to 

read that perchlorate, found in studies to impair the thyroid gland as well as the development of 

infants, has been found in our drinking water and the epa is not requiring that it be eliminated. How 

can we not protect something so essential as drinking water and make it as pure as possible? I firmly 

believe the epa should do whatever is possible to eliminate the existence of perchlorate in our 

drinking water. 

Nikki black michigan 

Response: See response to comment code 6120. 

Commenter Name: L.W. DeLap 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0830 

EPA Comment ID: 20104 

EPA Comment Code: 6120 

 

Comment: The evidence is clear that perchlorate is toxic. Contamination is widespread. Federal 

regulation of the level of perchlorate in public drinking water is needed to protect the US 

population. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0831 

EPA Comment ID: 20105 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to rise above the political 

machinations surrounding this issue and reverse its preliminary determination on setting a regulation 

for perchlorate in drinking water. It is important that the American public can rely on the EPA 

making decisions based solely on scientifically determined health risks rather than on potential risks 

to special interest groups. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0833 

EPA Comment ID: 20106 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 665 of 1099

 

Comment: We want clean safe drinking water shouldn't that be obvious, don't you? 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0838 

EPA Comment ID: 20107 

EPA Comment Code: 6120 

 

Comment: Please control percholorate in drinking water- humans are part of the environment and 

we too need protection. We already have had thyroid cancer in our household, and since this 

chemical attacks the thyroid, we do not want to again deal with this issue. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0841 

EPA Comment ID: 20109 

EPA Comment Code: 6120 

 

Comment: Any and all contaniments must be regulated in our public drinking water, no matter how 

small the threat. 

Response: See response to comment code 6120. 

Commenter Name: Anne Hall 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0847 

EPA Comment ID: 20110 

EPA Comment Code: 6120 

 

Comment: Keep perchlorate out of our drinking water! Its a dangerous chemical and all Americans 

deserve to at least trust that the major substance that we all need to stay alive is safe to drink! It is 

ridiculous to even call yourselves the "Environmental Protection" Agency if this is the kind of 

contamination you would consider allowing. 

I urge the U.S. Environmental Protection Agency to reverse its preliminary determination on setting 

a regulation for perchlorate in drinking water. Sincerely, Anne Hall Austin, TX 

Response: See response to comment code 6120. 

Commenter Name: Marjorie Curtiss 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0850 

EPA Comment ID: 20111 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 666 of 1099

EPA Comment Code: 6120 

 

Comment: To Whom This May Concern; 

In my opinion this is "everyones" concern! 

Please do not relax any regulations on drinking water safety, ever. Do we really have to keep 

bringing topics like this to the attention of the Federal Government? This is a "no brainer" 

fella's...YOU are the EPA! Sincerely, Marjorie Curtiss 

Response: EPA is not "relaxing any regulations on drinking water safety," rather EPA has 

determined to regulate perchlorate in drinking water. See response to comment code 6120. 

Commenter Name: S. Spencer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0852 

EPA Comment ID: 20112 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. We must be able to provide 

clean, safe water to Americans and perchlorate contamination is a serious issue. Please take the 

responsible action and reverse this decision. 

Response: See response to comment code 6120. 

Commenter Name: Susan Luberto 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0853 

EPA Comment ID: 20113 

EPA Comment Code: 6120 

 

Comment: I feel we have to protect our drinking water from any problems that could harm us now 

and later in life, please follow up and check on the Perchorate that is in the water to make sure it 

does not stay there. 

Thank you.Susan Luberto 

Response: See response to comment code 6120. 

Commenter Name: L. Thorp 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0858 

EPA Comment ID: 20114 

EPA Comment Code: 6120 

 

Comment: Please no perchlorate in the water. What will be allowed next? 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 667 of 1099

Response: See response to comment code 6120. 

Commenter Name: Kathleen Abke 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0861 

EPA Comment ID: 20115 

EPA Comment Code: 6120 

 

Comment: I believe it is a mistake to not regulate perchlorate in our drinking water. Please reverse 

your decision. 

Kathleen Abke Grosse Pointe Woods, MI 

Response: See response to comment code 6120. 

Commenter Name: T. Harris 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0862 

EPA Comment ID: 20116 

EPA Comment Code: 6120 

 

Comment: I urge the EPA to reverse its decision not to regulate perchlorate in drinking water 

supplies. This is a nasty chemical that I certainly do not want in my water, regardless of the impacts 

such legislation might have on industry. People's health should always come before any economic 

implications. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0864 

EPA Comment ID: 20117 

EPA Comment Code: 6120 

 

Comment: Nobody wants rocket fuel in their drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0867 

EPA Comment ID: 20118 

EPA Comment Code: 6120 

 

Comment: This should be an easy decision; do you want your grandchildren drinking water tainted 

with perchlorate? Do you think anyone in this country wants that? I can only think that the makers 

of perchlorate would not object to such a contamination but in someone else's water, not their own. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 668 of 1099

Since you should be concerned with the public's health it is confusing that you would even consider 

such a thing. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0871 

EPA Comment ID: 20119 

EPA Comment Code: 6120 

 

Comment: please do not allow perchlorate in drinking water 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0873 

EPA Comment ID: 20120 

EPA Comment Code: 6120 

 

Comment: I urge the U. S. Environmental Protection Agency to reverse its peliminary detemintion 

on setting a regulation for perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: 

Commenter Organization: Bethlehem Area School District 

EPA Document ID: EPA-HQ-OW-2008-0692-0874 

EPA Comment ID: 20121 

EPA Comment Code: 6120 

 

Comment: Why is this even an issue? If perchlorate is used in jet fuel...it does NOT belong in our 

drinking water. Let's just clean up our act regarding water instead of adding more chemicals to it to 

kill whatever is in there already! Water should not be an issue as far as priority. Please get it cleaned 

up the correct way. (Floride is next...it was used to kill rats...and it's in many water systems, ugh!!!) 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0875 

EPA Comment ID: 20122 

EPA Comment Code: 6120 

 

Comment: To Whom it May Concern, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 669 of 1099

Please reverse your preliminary determination in regard to regulating perchlorate in drinking water. 

Even small amounts can affect our public health and that of our children. Please take your role as a 

protector of our environment seriously. 

LL Franklin, MA 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0876 

EPA Comment ID: 20123 

EPA Comment Code: 6120 

 

Comment: I am not from a government agency or an official representative. But what I do 

represent is my family and most importantly, my children. Our drinking water needs to be safe for 

the American people and considering to not regulate possible contaminants such as perchlorate is 

very detrimental to all of our health and well being. Please reconsider this docket and do not pass it. 

We need our drinking water regulated. 

Thank You. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0877 

EPA Comment ID: 20124 

EPA Comment Code: 6120 

 

Comment: No rocket fuel in our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0879 

EPA Comment ID: 20125 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: C. H. Lynt 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0880 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 670 of 1099

EPA Comment ID: 20126 

EPA Comment Code: 6120 

 

Comment: As an Engineer with an advanced degree, and an attorney, I am hereby urging the EPA 

(U.S. Environmental Protection Agency) to reverse its preliminary decision not to regulate 

perchlorate in drinking water. 

My reasons include the following: 

It is well established that perchlorate contamination is a nationwide problem. Perchlorate 

contamination has been shown (citations omitted) to have health effects at lower levels than 

previously understood. 

A nationwide standard for primary drinking water regulation would provide an important and 

meaningful opportunity to protect the public health. 

Perchlorate is a harmful chemical used, for example, in rocket fuel, flares, and explosives. 

In small amounts, perchlorate can impair the thyroid gland, which regulates growth, development 

and metabolism. 

It is well known that developing fetuses, infants and children with thyroid impairment may suffer 

mental retardation, loss of hearing and speech or deficits in motor skills. 

The EPA has evidence that perchlorate has been found in at least 395 sites in 37 states, including 

153 public water systems serving over 20 million people. Many reliable estimates suggest an even 

wider contamination. 

This is an important public health issue that needs to be addressed in a responsible manner. 

Response: Please see the response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0881 

EPA Comment ID: 20127 

EPA Comment Code: 6120 

 

Comment: No Perchlorate in our drinking water. If there aren't already enough worries about what 

is already allowed in our drinking water, why this too? 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0882 

EPA Comment ID: 20128 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 671 of 1099

 

Comment: Please reverse your decision. We do NOT want perchlorate in our drinking water! It 

needs to be regulated. 

Response: See response to comment code 6120. 

Commenter Name: Elizabeth A. Carapico 

Commenter Organization: Arrowroot Natural Foods, LLP 

EPA Document ID: EPA-HQ-OW-2008-0692-0888 

EPA Comment ID: 20129 

EPA Comment Code: 6120 

 

Comment: To the EPA Personnel: 

Your very name indicates your obligation to protect the environment and the vegetation and animal 

life (including people) dependent on that environment. 

Knowingly allowing a dangerous contaminant into the water supply is paramount to putting it there 

with your own hand; and thus the dangerous ramnifications are on your shoulders personally. 

Anything that has a negative effect should be regulated to the nth degree. 

Perchlorate falls into this catagory. 

I urge you to keep perchlorate out of our drinking water. 

Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Shanoah LaPatka 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0894 

EPA Comment ID: 20130 

EPA Comment Code: 6120 

 

Comment: Explain to me why perchlorate is not being regulated. It should be banned. Anything 

that is not naturally found in water should not be added to it. With all the facts how can you even be 

questioning it. Because of the added expense to remove it or not put it there at all? We can't live 

without clean water! This is a no brainer! 

Thank you, Shanoah LaPatka 

Response: See response to comment code 6120. 

Commenter Name: Elise Roman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0895 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 672 of 1099

EPA Comment ID: 20131 

EPA Comment Code: 6120 

 

Comment: It is important to do everything possible to provide to keep our drinking water clear of 

Perchlorate. It is outrageous to think that any levels would be acceptable for consumption by 

anyone, let alone the sick, elderly, young and those with compromised immune systems. 

This is a nationwide problem that needs to be addressed. It is more costly to deal with the adverse 

affects of Perchlorate in our drinking water than to deal with health effects on our general 

populations. 

Please regulate and ban this substance from our drinking water. 

Elise Roman 

Response: See response to comment code 6120. 

Commenter Name: P. Nardizzi 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0899 

EPA Comment ID: 20132 

EPA Comment Code: 6120 

 

Comment: Protection Agency to reverse its preliminary determination on setting a regulation for 

perchlorate in drinking water. Committee for people who don;t want to die. Bring back the 

American Indian 

Response: See response to comment code 6120. The American Indian is outside the scope of this 

notice. 

Commenter Name: James Gambucci 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0903 

EPA Comment ID: 20133 

EPA Comment Code: 6120 

 

Comment: Hello. 

Please keep Perchlorate out of our water!! 

Thank you. 

-James Gambucci 

Response: See response to comment code 6120. 

Commenter Name: John Porzondek 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 673 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-0904 

EPA Comment ID: 20134 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Nothing should be in water except WATER. 

Please stop it for our children's and future's sake. 

Thank you, John Porzondek 790 Lake Street Saugatuck, MI 49453-9435 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0910 

EPA Comment ID: 20135 

EPA Comment Code: 6120 

 

Comment: Please keep poison out of the water! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0913 

EPA Comment ID: 20136 

EPA Comment Code: 6120 

 

Comment: a national primary drinking water regulation would provide a meaningful opportunity to 

protect public health. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0914 

EPA Comment ID: 20137 

EPA Comment Code: 6120 

 

Comment: I support regulations and legislation that keeps perchlorate out of our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 674 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-0915 

EPA Comment ID: 20138 

EPA Comment Code: 6120 

 

Comment: No perchlorate in our water!!! None! 

Response: See response to comment code 6120. 

Commenter Name: Jeffrey Ramsey 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0920 

EPA Comment ID: 20139 

EPA Comment Code: 6120 

 

Comment: I urge the US EPA to reconsider its position on the regulation of perchchlorate in 

drinking water. This is a nationwide problem. Perchchlorate-contaminated drinking water has been 

found to to have negative health impacts at lower levels than previously recorded, particularly 

affecting the thyroid gland of developing fetuses, infants and children. Our children deserve 

protection through regulation of this hazardous contaminant. 

Please reverse your decision concerning perchchlorate regulation. 

Kind regards, Jeffrey Ramsey 3315 Heidelberg Drive Boulder, CO 80305 

Response: See response to comment code 6120. 

Commenter Name: G. MacCallum 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0923 

EPA Comment ID: 20140 

EPA Comment Code: 6120 

 

Comment: You are insane to consider this. Fresh, clean water, so deeply necessary to all life, must 

be protected. Consideration of "acceptable" levels of any one chemical cannot exclude conscious 

study of how the myriad of other toxins and pharmaceuticals flowing into our environment in 

combination impact human life. 

Response: See response to comment code 6120. 

Commenter Name: Alex Milbank 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0924 

EPA Comment ID: 20141 

EPA Comment Code: 6120 

 

Comment: Perchlorate is dangerous and should not be allowed in drinking water supplies. Please 

reverse your decision and protect humans and the environment. Thank you for your consideration. 

Alex Milbank 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 675 of 1099

Response: See response to comment code 6120. 

Commenter Name: Sarah Smith 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0925 

EPA Comment ID: 20142 

EPA Comment Code: 6120 

 

Comment: I don't want rocket fuel in my drinking water. Please reverse your decision and regulate 

water for perchlorate. It is very harmful to human health and should not be in our drinking water. 

Thank you, 

Sarah Smith citizen Belmont, MA 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0929 

EPA Comment ID: 20143 

EPA Comment Code: 6120 

 

Comment: If the government is aware of the presence of a potentially harmful contaminant in 

drinking water, it is their obligation to monitor it, study the health effects and fully understand the 

threat to the best of its ability. To do otherwise, such as ignoring it, is negligent. 

Please regulate perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: M. Doyle 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0932 

EPA Comment ID: 20144 

EPA Comment Code: 6120 

 

Comment: I do not understand why the EPA would allow anything in our drinking water that is 

not supposed to be there even if there is not â€ ̃â€ ̃a meaningful opportunity for health risk 

reduction for persons served by public water systems.â€TMâ€TM Please regulate the water so that we 

are not drinking Perchlorate! 

Response: See response to comment code 6120. 

Commenter Name: W. Petry 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0933 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 676 of 1099

EPA Comment ID: 20145 

EPA Comment Code: 6120 

 

Comment: Plaese continue to regulate perchlorates in our drinking water. 

Response: EPA does not currently regulate perchlorate in drinking water; however, EPA has 

determined to regulate perchlorate in drinking water. See response to comment code 6120. 

Commenter Name: E. Ralph 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0934 

EPA Comment ID: 20146 

EPA Comment Code: 6120 

 

Comment: We should not have perchlorate in our drinking water. Perchlorate contamination is a 

nationwide problem and has health impacts at lower levels than previously thought. The last months 

of a presidency is not the time to be rushing through controversial regulation. 

Response: See response to comment code 6120. 

Commenter Name: Roberta Masters-Cullen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0936 

EPA Comment ID: 20147 

EPA Comment Code: 6120 

 

Comment: Dear Sir/Madam, 

I strongly urge you to remember the environmental PROTECTION part of your agency's 

philosophy and ask you to please regulate perchlorate in our drinking water. Your department was 

founded to protect us - please don't let an ingredient that's used in rocket fuel go unregulated in our 

drinking water. 

Roberta Masters-Cullen Alexandria, Virginia 

Response: See response to comment code 6120. 

Commenter Name: D. Fahrmann 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0938 

EPA Comment ID: 20149 

EPA Comment Code: 6120 

 

Comment: As with all chemicals in the water...you know it will affect animals and humans in a 

negative way. You don't need to spend millions to figure it out -just attack the problem in any way 

you can to reduce the levels of the chemical. 

At a minimum, the EPA needs to regulate Perchlorate. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 677 of 1099

Response: See response to comment code 6120. 

Commenter Name: W. Calvert 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0941 

EPA Comment ID: 20150 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Please control the amount of perchlorate in our drinking water. This substance is harmful to human 

health. Not only is it your duty to do this, it is the morally correct thing to do. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0942 

EPA Comment ID: 20151 

EPA Comment Code: 6120 

 

Comment: Please keep drinking water clean for everyone 

Response: This is not a comment, no response is needed. 

Commenter Name: Elizabeth Saunders 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0943 

EPA Comment ID: 20152 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to regulate perchlorate in drinking 

water. The preliminary determination to refrain from setting such a regulation is irresponsible. 

Perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought. As someone with an impaired thyroid gland I do not like considering the 

possibility that my drinking water might at any time contain a chemical known to cause thyroid 

damage. I hate to think (not that I will ever know) that this might be the cause, or that drinking 

contaminated water would worsen my health. 

To ignore this problem and avoid setting a standard for perchlorate in drinking water is 

inappropriate. We citizens count on our government agencies to protect our water and our health 

and this is one example of where that is necessary. 

Please reverse the determination. 

Sincerely, Elizabeth Saunders Dorchester, MA 02122 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 678 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0945 

EPA Comment ID: 20153 

EPA Comment Code: 6120 

 

Comment: I am writing to urge the EPA to please regulate perchlorate in our drinking water. I type 

medical reports for an Oncology Center. Cancer rates are skyrocketing in this country. We don't 

need another contaminant to make the situation worse. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0948 

EPA Comment ID: 20154 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: G. Breese 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0949 

EPA Comment ID: 20155 

EPA Comment Code: 6120 

 

Comment: It is vitally important to the health and safety of all Americans, particularly children and 

developing fetuses, that the EPA reverse its finding and regulate perchlorate to keep it out of our 

drinking water! Such chemicals in our daily drinking water can do more long and short term damage 

than any terrorist could ever hope to do. Please reverse your decisions and keep Americans strong 

and healthy -- don't contribute to weakening our country just to save a few dollars. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: M. Roberts 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0951 

EPA Comment ID: 20156 

EPA Comment Code: 6120 

 

Comment: Please DO regulate the perchlorate in drinking water. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 679 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0952 

EPA Comment ID: 20157 

EPA Comment Code: 6120 

 

Comment: Perchlorate needs to be regulated. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0954 

EPA Comment ID: 20158 

EPA Comment Code: 6120 

 

Comment: We need to keep our water clean! I hope you will reverse this decision and regulate this 

chemical. 

Response: See response to comment code 6120. 

Commenter Name: Jerise Fogel 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0957 

EPA Comment ID: 20159 

EPA Comment Code: 6120 

 

Comment: What is the EPA for, if not to regulate items such as this? I have no idea why adding 

Perchlorate to the list of regulated chemicals that should not be added to drinking water would be a 

sticking point for my Environmental Protection Agency, unless some large producer(s) of 

Perchlorate who habitually let them leach into our drinking water is/are paying someone off. 

EPA, please do your job. Regulate Perchlorate! 

Sincerely, 

Jerise Fogel 

Response: See response to comment code 6120. 

Commenter Name: Angela Christman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0960 

EPA Comment ID: 20160 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 680 of 1099

Comment: Reverse this decision!! This is a bad decision which is bad for the environment and for 

our health! Reverse it now! 

Angela Christman Catonsville, MD 21228 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0964 

EPA Comment ID: 20161 

EPA Comment Code: 6120 

 

Comment: How can anyone imagine any amount of perchlorate is tolerable or safe in drinking 

water? It must also be banned in water for irrigation of crops and for animals. This chemical is toxic, 

toxic, toxic!! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0965 

EPA Comment ID: 20162 

EPA Comment Code: 6120 

 

Comment: Reverse your finding and regulate perchlorate in drinking water!!! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0967 

EPA Comment ID: 20163 

EPA Comment Code: 6120 

 

Comment: Please ban Perchlorate from drinking water!! Nobody wants to drink that, just so the 

companies who produced it have an easier way of getting rid of it! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0970 

EPA Comment ID: 20164 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 681 of 1099

Comment: I URGE THE U.S. ENVIRONMENTAL PROTECTION AGENCY TO REVERSE 

ITS PRELIMINARY DETERMINATION ON SETTING A REGULATION FOR 

PERCHLORATE IN DRINKING WATER. 

Response: See response to comment code 6120. 

Commenter Name: Philip Katz 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0971 

EPA Comment ID: 20165 

EPA Comment Code: 6120 

 

Comment: I am a strong supporter of regulations maintaining clean air and water. Therefore I ask 

that you regulate the amount of percholate in our water supply. I ask that you make the level as 

scientifically possible. 

Thank you, 

Philip Katz Citizen 37 Kensington Ave. West Newton, Ma 02465 philkatz@rcn.com 

Response: See response to comment code 6120. 

Commenter Name: Kristin Flora 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0973 

EPA Comment ID: 20166 

EPA Comment Code: 6120 

 

Comment: Please regulate Percholarate in our water. We know that certain levels of this chemical 

have been found to be harmful. Why would you want to intentionally ignore the levels of this 

harmful chemical in the water that we drink? Please reconsider your decision concerning the 

regulation of this harmful checmical. 

Kristin Flora South Riding, VA 

Response: See response to comment code 6120. 

Commenter Name: S. Picciuca 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0976 

EPA Comment ID: 20167 

EPA Comment Code: 6120 

 

Comment: Water uncontaminated is the right of all living beings on this planet.Our security begins 

with safe water and nothing supercedes it.Please do your duty. 

Response: This is not a comment, a response is not necessary. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 682 of 1099

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0977 

EPA Comment ID: 20168 

EPA Comment Code: 6120 

 

Comment: Why on earth would you allow Perchlorate in my drinking water? This is not acceptable. 

Please fix this! 

Response: See response to comment code 6120. 

Commenter Name: J. V. Blargan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0983 

EPA Comment ID: 20169 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. In California, perchlorate 

contamination in the groundwater has literally poisoned wells, and now it's okay, somehow? 

Studies are already showing health impacts at lower levels than previously imagined and threatens of 

water supply. We need a national primary drinking water regulation to protect public health. 

Bisphenol-A and Perchlorate are in a class of endocrine disrupters that impair the thyroid gland, 

which controls growth, metabolism, and development, especially in fetuses, infants and children. 

EPA agrees that perchlorate has been found in 395 sites in 37 states, including 153 public water 

systems serving over 20 million people. Some estimates are even higher. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0984 

EPA Comment ID: 20170 

EPA Comment Code: 6120 

 

Comment: I can't believe there would even be a question as to whether or not to regulate the 

amount of perchlorate in water. What could possibly be a plausible reason? For the sake of children 

alone, this should be a no-brainer. The fact that there is even a question is frankly disgusting to me. 

Our government at work looking out for our best interest, obviously. I hope no one at the EPA has 

a pregnant wife or children gulping down the contaminated water. Do what's right, no matter what 

the cost!! We are talking about people's health here! 

Response: See response to comment code 6120. 

Commenter Name: B. Steinmetz 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 683 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0991 

EPA Comment ID: 20171 

EPA Comment Code: 6120 

 

Comment: Please. I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. Nothing is more important 

than public heath. 

Response: See response to comment code 6120. 

Commenter Name: Richard Lee 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0994 

EPA Comment ID: 20172 

EPA Comment Code: 6120 

 

Comment: I can't believe that anyone actually has to write to express their concern against not 

regulation a poison in our drinking water. What is going on here? Please reverse this reckless and 

devastating decision before more people are poisoned. 

Thank you for your consideration. Richard Lee, Berkley, MI 

Response: See response to comment code 6120. 

Commenter Name: D. Edwards 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0995 

EPA Comment ID: 20173 

EPA Comment Code: 6120 

 

Comment: EPA must regulate Perchlorate in drinking water! It is too dangerous for public health. 

Response: See response to comment code 6120. 

Commenter Name: T. Coutinho 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0998 

EPA Comment ID: 20174 

EPA Comment Code: 6120 

 

Comment: Our water must be protected............................ 

Response: This is not a comment, a response is not necessary. 

Commenter Name: L. C. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1000 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 684 of 1099

EPA Comment ID: 20175 

EPA Comment Code: 6120 

 

Comment: I urge the EPA to reconsider their decision not to regulate perchlorates in the drinking 

water. 

Perchlorates can have a negative effect on the thyroid gland which impacts the development and 

growth of born and unborn children. We need to protect our drinking water and our health. 

Thank you. L.C. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1004 

EPA Comment ID: 20176 

EPA Comment Code: 6120 

 

Comment: Please, NO rocket fuel allowed in the water!!!!! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1005 

EPA Comment ID: 20177 

EPA Comment Code: 6120 

 

Comment: As a citizen and a volunteer leader for the Boy Scouts of America, this just doesn't 

sound right to me. I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. Water is the essence of life 

on Earth, let's keep it clean! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1011 

EPA Comment ID: 20178 

EPA Comment Code: 6120 

 

Comment: take the rocket fuel out of our fuckin drinking water 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 685 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-1013 

EPA Comment ID: 20179 

EPA Comment Code: 6120 

 

Comment: I urge the EPA to carefully examine the health effects of any level of Perchlorate in the 

nation's drinking water. 

Response: See response to comment code 6120. 

Commenter Name: P. & T. Lyon 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1014 

EPA Comment ID: 20180 

EPA Comment Code: 6120 

 

Comment: PLEASE regulate perchlorate contaimination in drinking water. We are deeply 

disappointed in this administration's conservation and environmental record AND WE VOTED 

FOR YOU. At the least, our government needs to address the qualiity of water and protect future 

generations. The damage in the last century in the Great Lakes is now damage forever and becoming 

acceptable. IT IS NOT ACCEPTABLE. 

I HATE MORE REGULATIONS BUT REGULALTE PERCHLORATE. The job of the federal 

government is to protect our nation, do it. 

Response: See response to comment code 6120. 

Commenter Name: Miguel A. Diaz 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1015 

EPA Comment ID: 20181 

EPA Comment Code: 6120 

 

Comment: This is a request to ask you, to please Keep perchlorate out of our drinking water. 

Thank you, 

Miguel A. Diaz 

Response: See response to comment code 6120. 

Commenter Name: Ed Olmstead 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1016 

EPA Comment ID: 20182 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 686 of 1099

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water perchlorate contamination is 

a nationwide problem. 

I do not, nor do I know if anyone can prvoe beyond a thin shadow of a doubt that perchlorate is 

harmful to life. However, when it comes to public good and the health of the country the fact that 

perchlorate is likely to be harmful in ways we know and don't know at this time is more than enough 

evidence to regulate this contaminant. 

The job of the EPA is to protect the environment. The job the EPA is not to protect the 

corporations and the obscene corporate profits and practices that have led this country into a 

disastorous position financially and politically. I strongly urge you to work for the public good and 

give up the policies of the last eight years of protecting military/industrial complex at the expense of 

the US citizenry. A effective military does not have to be maintained at the expense of poisoning our 

own people. Do the right thing and regulate this poison in the environment. 

Ed Olmstead 43 Stilson Ave Florence, MA 01062 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1018 

EPA Comment ID: 20183 

EPA Comment Code: 6120 

 

Comment: The EPA is becomming a spot on this nations system. Instead of protecting the 

eniroment, they're safeguarding ways to further pollute our waters. When is this madness going to 

stop? 

Response: This is not a comment, a response is not necessary. 

Commenter Name: L. M. Maloney 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1021 

EPA Comment ID: 20184 

EPA Comment Code: 6120 

 

Comment: I am not an organization. I am a mother and grandmother. I don't want my 

grandchildren drinking perchlorate. It is essential that the EPA maintain standards for drinking 

water that will protect our next generation from the kind of disasters we see happening in China. 

Can we preserve an environment fit for our children? Yes we can! 

Response: See response to comment code 6120. 

Commenter Name: Richard R. Quick 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1028 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 687 of 1099

EPA Comment ID: 20185 

EPA Comment Code: 6120 

 

Comment: I support the regulation of perchlorate in drinking water. It should have happened a 

long time ago and the agencies responsible for allowing it into the water supply should have been 

stopped and disciplined a long time ago. 

Why would anyone want the by products or components of rocket fuels in their water? 

Richard R. Quick 15150 Warwick Detroit, Mi 48223 

Response: See response to comment code 6120. 

Commenter Name: Beth Robelia 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1033 

EPA Comment ID: 20187 

EPA Comment Code: 6120 

 

Comment: To whom it may concern: 

Your decision not to regulate perchlorate is irresponsible and will have tragic consequences for 

pregnant women and young children. 

The 153 public water systems that are affected by this contamination will impact the lives of over 20 

million people. 

Please reconsider your decision. None of us would want to leave this sort of contamination for our 

children. I am sure none of the EPA personnel involved would want their children or grandchildren 

drinking water contaminated with perchlorate and you should not pretend that it would be OK for 

"other people." 

Thank you for reconsidering your decision, 

Beth Robelia, Ph.D. 

Response: See response to comment code 6120. 

Commenter Name: S. Randolph 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1034 

EPA Comment ID: 20188 

EPA Comment Code: 6120 

 

Comment: I understand that the U.S. EPA issued a preliminary determination not to regulate 

perchlorate in drinking water. I urge you to reverse this determination. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 688 of 1099

The health risks particularly to the thyroid gland of children of even small amounts of perchlorate 

are severe enough to demand regulation. 

Perchlorate contamination is not a rare event but has been found to be a nationwide problem. 

Given the adverse health impacts of even lower levels than previously found problematic, it is 

essential that this contaminate be regulated to protect the public's health. 

Response: See response to comment code 6120. 

Commenter Name: P. Turner 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1036 

EPA Comment ID: 20189 

EPA Comment Code: 6120 

 

Comment: NO PERCHLORATE in PUBLIC WATER ! ! ! 

How many ways can you spell poison? 

Response: See response to comment code 6120. 

Commenter Name: Anne Felosak 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1038 

EPA Comment ID: 20190 

EPA Comment Code: 6120 

 

Comment: To those responsible for keeping our drinking water as healthy and free from 

contaminants as possible: I strongly urge you to reconsider letting any chemicals be given a pass as 

safe in our drinking water and even in the environment. We have to be more careful than ever about 

upsetting the balances in nature. Please keep our water as pure as possible. Anne Felosak 

Response: See response to comment code 6120. 

Commenter Name: S. Denmark 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1039 

EPA Comment ID: 20191 

EPA Comment Code: 6120 

 

Comment: I am a private citizen and urge you to reverse the decision to not regulate perchlorate in 

drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Sara Dovre Wudali 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 689 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-1047 

EPA Comment ID: 20192 

EPA Comment Code: 6120 

 

Comment: Hi, 

I am concerned about perchlorate in drinking water. I would like to have faith that my tap water is 

as clean as we can make it. I'm worried about the potential health problems and growth problems 

linked to percholorate. Please consider regulating it. 

Thanks, Sara Dovre Wudali St. Paul, MN 

Response: See response to comment code 6120. 

Commenter Name: Katie Giddings 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1051 

EPA Comment ID: 20193 

EPA Comment Code: 6120 

 

Comment: My family and I drink tap water rather than bottled water because of the harmful 

environmental effects of plastic bottles and the wasted energy of shipping water in bottles. Please do 

not endanger our health by allowing poisons into our precious drinking water. I ask the EPA to 

regulate perchlorate in drinking water, along with any other substances that can cause harm and 

might be found in our water. The Environmental Protection Agency needs to begin living up to its 

name again rather than being the agency to eliminate needed protections. 

Thank you. 

Katie Giddings 27 Turner St #2, Salem MA 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1052 

EPA Comment ID: 20194 

EPA Comment Code: 6120 

 

Comment: no no no! what is the matter with you people? do your job please, which is to protect 

me, not put me at risk. 

thank you 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 690 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-1054 

EPA Comment ID: 20195 

EPA Comment Code: 6120 

 

Comment: Dear EPA: 

I've been working with communities over the past eight years to reduce pollutants in stormwater as 

required by Phase II of the Clean Water Act. Countless hours and dollars later, communities are 

making headway in cleaning up our surface waters. My region of the county gets its drinking water 

from the Detroit River, where I'm sure the industrial history of the area has deposited perchlorate 

into the Detroit River. Please join communities in protecting our water resources and regulate this 

dangerous chemical in our drinking water. You have required communities to minimize pollutants in 

our lakes and streams. Now please do your part in continuing our progress in protecting our 

drinking water. 

Thank you. 

Response: See response to comment code 6120. 

Commenter Name: D. Knutson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1055 

EPA Comment ID: 20196 

EPA Comment Code: 6120 

 

Comment: Keep perchlorate out of drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1057 

EPA Comment ID: 20197 

EPA Comment Code: 6120 

 

Comment: To the decision makers at the EPA: 

Perchlorate laced drinking water. Would YOU drink this? Would you let your KIDS drink this? 

PLEASE: DO YOUR JOB. If Bush prohibits you from doing it, please make HIM drink this. 

Thanks. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1061 

EPA Comment ID: 20198 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 691 of 1099

 

Comment: Please don't allow Perchlorate in our Drinking Water: Preliminary Regulatory 

Determination on Perchlorate 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1065 

EPA Comment ID: 20199 

EPA Comment Code: 6120 

 

Comment: I am writing to urge you to regulate the allowable limits of perchlorate in this nation's 

drinking water. With many safety questions still outstanding, this is a necessary step not only to 

protect the public health, but also to bolster public confidence in the ability of government 

regulators to take a stand against the interests of industry and act first in the best interest of the 

citizens of this country. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Fran Sugarman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1066 

EPA Comment ID: 20200 

EPA Comment Code: 6120 

 

Comment: We are very concerned by the recently announced decision of the EPA to not regulate 

perchlorate in our drinking water. Perchlorate is an extremely harmful chemical used in rocket flares 

and explosives. We do not want to see our children exposed to this contaminant. 

In the spirit of our new President- please listen to our concerns -and what parents want and reverse 

your decision. 

Sincerely Fran Sugarman 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1067 

EPA Comment ID: 20202 

EPA Comment Code: 6120 

 

Comment: May you suffer from the toxins which you permit in our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: B. McCollum 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 692 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1068 

EPA Comment ID: 20203 

EPA Comment Code: 6120 

 

Comment: The U.S. Environmental Protection Agency should reverse its preliminary determination 

on setting a regulation for perchlorate in drinking water. Isn't this what your mission is about-- To 

protect the public and the environment from harmful contamination and pollution? Perchlorate 

contamination is a national problem and has severe health impacts that affect us all, especially the 

most vulnerable among us. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1072 

EPA Comment ID: 20204 

EPA Comment Code: 6120 

 

Comment: What is the thinking here? Please act immediately and regulate Perchlorate in our 

drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Peggy Rinard 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1075 

EPA Comment ID: 20206 

EPA Comment Code: 6120 

 

Comment: Please reverse the EPA decision not to regulate perchlorate in drinking water. 

Peggy Rinard 4469 Evergreen Drive St. Paul, MN 55127 

Response: See response to comment code 6120. 

Commenter Name: Patrick L. Doss-Smith 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1076 

EPA Comment ID: 20207 

EPA Comment Code: 6120 

 

Comment: To whom it may concern, 

Please reconsider the EPA's preliminary determination concerning regulation of Perchlorate levels in 

our drinking water. I am particularly concerned about potential damage to the thyroid in a 

developing fetus. As you may know, damage during development can lead to serious problems such 

as retardation, loss of hearing, etc. These sorts of issues are devastating to the individuals affected 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 693 of 1099

and costly to our society. We must not let short term profits harm the long term health and well 

being of the ecosystem and subsequently, us. We need stronger regulation of Perchlorate. 

Respectfully, 

Patrick L. Doss-Smith 

Response: See response to comment code 6120. 

Commenter Name: B Seng 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1080 

EPA Comment ID: 20208 

EPA Comment Code: 6120 

 

Comment: Please take action to regulate perchlorate in drinking water. At the very least you must 

have programs in place to measure the amounts in public drinking water systems so that consumers 

can know whether or not they are protected. This action will also spur water filter manufacturers to 

come up with solutions for consumers. 

Response: See response to comment code 6120. 

Commenter Name: B Ferguson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1081 

EPA Comment ID: 20209 

EPA Comment Code: 6120 

 

Comment: Keep rocket fuel out of our drinking water. Reverse this decision. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1082 

EPA Comment ID: 20210 

EPA Comment Code: 6120 

 

Comment: When are you going to stop killing us? We need drinkable water. Why are you doing 

this? 

Response: This is not a comment, no response necessary. 

Commenter Name: James W. Smith 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1083 

EPA Comment ID: 20211 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 694 of 1099

 

Comment: We must not allow Perchlorate in our water. This chemical is harmful and must be 

regulated from all water used by our citizens. Thank you. 

Sincerely, James W. Smith 821 Heritage Point Chesapeake, VA 23322 

Response: See response to comment code 6120. 

Commenter Name: E Paulson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1087 

EPA Comment ID: 20212 

EPA Comment Code: 6120 

 

Comment: Please regulate the amount of perchlorate in our drinking water. It is harmful to the 

thyroid, the thyroid effects not only our metabolism, but our heart. My cousin a middle aged man of 

52 has a heart which is only functining at 25%, because of damaged sustained from a dysfunctioning 

thyroid. The thyroid damage and heart damage has affected his life and family. Perchlorate is a 

highly reactive compound and considering the other organic chemical componds in our water, what 

other products will they be forming which will be effecting our bodies? Please reconsider and 

regulate this compond in our water. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: E.E. Jumikis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1090 

EPA Comment ID: 20213 

EPA Comment Code: 6120 

 

Comment: The recent decision by the Environmental Protection Agency not to issue standards for 

perchlorate in drinking water is a profligate flight from its regulatory responsibility. As a victim of 

oral cancer which has fried my thryroid, I am very sensitive to the effects of perchlorate on thyroid 

function and development. I understand how a lack of prescience can lead to disastrous 

consequences. As our children proliferate mental afflictions like ADHD, autism and other mental 

impairments, EPA must not abandon its responsibility to regulate perchlorate and other proven 

harmful chemicals in our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: John Ganapes 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1093 

EPA Comment ID: 20214 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 695 of 1099

Comment: I am writing to urge you to limit levels of Perchlorate in our drinking water to extremely 

low numbers. As a parent I am concerned about the health of my children and will not tolerate any 

risk to them at all. 

John Ganapes Minneapolis MN 55407 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1095 

EPA Comment ID: 20215 

EPA Comment Code: 6120 

 

Comment: EPA agrees that perchlorate has been found in 395 sites in 37 states, including 153 

public water systems serving over 20 million people. Some estimates are even higher. Thus 

perchlorate contamination is a nationwide problem--and has health impacts at lower levels than 

previously thought. 

Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development, and metabolism. Developing fetuses, infants, and children with thyroid impairment 

may suffer mental retardation, loss of hearing and speech, or deficits in motor skills. 

As a mother and as an American, I urge the U.S. Environmental Protection Agency to reverse its 

preliminary determination on setting a regulation for perchlorate in drinking water. This is not the 

time to take an unwarranted, dangerous step away from the mission of the Environmental 

Protection Agency to safeguard our citizens, young and old, from harmful containments in one of 

our country's most critical resources. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1096 

EPA Comment ID: 20216 

EPA Comment Code: 6120 

 

Comment: SInce we say we care about our environment, lets do what we say and take action to deal 

with this toxin before it gets too late. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1097 

EPA Comment ID: 20217 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 696 of 1099

Comment: This is a request for the U.S. EPA to reverse its preliminary decision not to regulate 

perchlorate in drinking water. Perchlorate can impair the thyroid gland and cause significant health 

risks to fetuses, infants and children. Perchlorate has been found in numerous water sources in the 

U.S. and the EPA should do its job and protect the public from such contamination. 

Response: See response to comment code 6120. 

Commenter Name: M. Hoover 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1098 

EPA Comment ID: 20218 

EPA Comment Code: 6120 

 

Comment: Please reverse your preliminary determination regarding regulations for perchlorate in 

drinking water. 

Perchlorate contamination is a problem across the country. It negatively impacts our health at lower 

levels that thought previously - with possible impairment to the thyroid. Of special concern is the 

impact on healthy thyroid function in fetuses, infants and children. Possible negative outcomes 

include mental retardation, hearing, speech and motor deficits. 

Perchlorate contamination has been found in hundreds of sites, more than 35 states and over a 150 

public water systems. 

Regulation by the EPA provides a necessary mechanism to protect our health. 

Response: See response to comment code 6120. 

Commenter Name: Chris Jones 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1100 

EPA Comment ID: 20219 

EPA Comment Code: 6120 

 

Comment: We do not want Perchlorate in our drinking water. If ground water has potential to be 

contaminated with Perchlorates then we need it monitored and evaluated. 

Thank you Chris Jones 

Response: See response to comment code 6120. 

Commenter Name: H. Kitrosser 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1104 

EPA Comment ID: 20220 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

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Comment: I am against your preliminary decision not to regulate perchlorate in drinking water. 

Please reconsider and keep our drinking water safe. 

Response: See response to comment code 6120. 

Commenter Name: Solo Greene 

Commenter Organization: Nez Perce Tribe 

EPA Document ID: EPA-HQ-OW-2008-0692-1106 

EPA Comment ID: 20221 

EPA Comment Code: 6120 

 

Comment: Water is one of the most sacred things to Native Americans, and without clean, quality 

water, we as a people aren't going to be here very much longer. The animals, birds, fish, vegetation 

and natural resources are already suffering because of contaminated water, and we don't need any 

more of it entering our water ways, especially when we can avoid it. Please do not allow this to 

happen. 

Response: See response to comment code 6120. 

Commenter Name: J. Blakeley 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1110 

EPA Comment ID: 20222 

EPA Comment Code: 6120 

 

Comment: Let's keep this pollutent out of our water! 

Response: See response to comment code 6120. 

Commenter Name: L.A. and S. Warner 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1115 

EPA Comment ID: 20223 

EPA Comment Code: 6120 

 

Comment: Perchlorate does not belong in water, and it should be a right of every American to have 

drinking water free of chemical contamination. My family is suffering from autoimmune issues. We 

notice more and more people who are dealing with chronic health issues and strongly believe that 

our country's loose use of synthetic products could be to blame. Keeping perchlorate out of 

drinking water is a no brainer. Why don't we start here! 

Response: See response to comment code 6120. 

Commenter Name: M.A. Baier 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1116 

EPA Comment ID: 20224 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 698 of 1099

 

Comment: no perchlorate in the drinking water/ regulate rocket fuel 

Response: See response to comment code 6120. 

Commenter Name: George Hasapidis 

Commenter Organization: Cumberland Grange 

EPA Document ID: EPA-HQ-OW-2008-0692-1120 

EPA Comment ID: 20225 

EPA Comment Code: 6120 

 

Comment: Please protect humans and other animals from the harm that drinking perchlorate does. 

This is a known toxin, and it is the EPA's responsibility to protect us from it. 

Response: See response to comment code 6120. 

Commenter Name: J. Fredrick 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1121 

EPA Comment ID: 20226 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; a national primary drinking water regulation would provide a meaningful 

opportunity to protect public health. 

I live in Michigan and believe that perchlorate is in my drinking water. I have a thyroid problem that 

I suffer with for the last 2 1/2 years. I have no insurance and have to pay for specialist and 

perscriptions out of pocket. 

Is your purpose in Washington to help save our viable drinking resources and the citizen's with 

which you represent?! 

Response: See response to comment code 6120. 

Commenter Name: Laurie Dixon 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1123 

EPA Comment ID: 20227 

EPA Comment Code: 6120 

 

Comment: To whom it may concern, 

It is crucial to my family as well as everyone I know that every measure be taken to protect our 

groundwater. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 699 of 1099

Living in Michigan, we have watched for decades upon decades as our environment has been 

decimated with toxic pollutiion. Everyone in this area lives near a "superfund" site. 

This is a huge issue for citizens, probably more than any government agency realizes. Cancer has 

become a plague in southeast Michigan. 

Please do everything possible, setting up whatever measures are needed to stop the contamination 

our water supply. 

Sincerely, Laurie Dixon 

Response: See response to comment code 6120. 

Commenter Name: Renee Kaiser-Muelken 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1124 

EPA Comment ID: 20228 

EPA Comment Code: 6120 

 

Comment: I strongly encourage the U.S. Environmental Protection Agency to reverse its 

preliminary determination on setting a regulation for perchlorate in drinking water. 

The EPA knows that perchlorate contamination is a nationwide problem and has health impacts at 

lower levels than previously thought, and that a national primary drinking water regulation would 

provide a meaningful opportunity to protect public health. And we must be responsible to protect 

the most vulnerable in our society, the children - our future. 

Thank you, Renee Kaiser-Muelken 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1125 

EPA Comment ID: 20229 

EPA Comment Code: 6120 

 

Comment: The EPA must stop now the Bush administration's poisoning of our water, our 

environment, our lives. I am sure the appointed political leaders of the EPA can make a last gasp 

effort to enrich corporate leaders and others who benefit financially if the EPA allows percholate 

and other poisons in our water, but it will be a shortlived decision, and we will remember for a long 

time those who tried to slip one by us on their way out the door. For those of you who might allow 

this to happen, goodbye and good riddance. 

Response: See response to comment code 6120. 

Commenter Name: J. Dreifus 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 700 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1127 

EPA Comment ID: 20230 

EPA Comment Code: 6120 

 

Comment: I think the EPA needs to reverse its position on regulating perchlorate. How can it not 

regulate this chemical? 

Response: See response to comment code 6120. 

Commenter Name: S. Eckes 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1128 

EPA Comment ID: 20231 

EPA Comment Code: 6120 

 

Comment: Please, no perchlorate in drinking water. 

Thanks. 

Response: See response to comment code 6120. 

Commenter Name: Phillip Lamoureux 

Commenter Organization: Michigan State University 

EPA Document ID: EPA-HQ-OW-2008-0692-1129 

EPA Comment ID: 20232 

EPA Comment Code: 6120 

 

Comment: Please regulate perchlorate levels in drinking water, and work to prevent groundwater 

perchlorate contamination from industrial and government sources. We need very low, safe 

standards for this pollutant. 

Sincerely, Phillip Lamoureux Biochemist and Cell Biologist Michigan State University 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0655 

EPA Comment ID: 20233 

EPA Comment Code: 6120 

 

Comment: As a pediatrician, I think it is unwise to increase the allowed amount of perchlorate in 

the drinking water. The fetus and he growing child are more sensitive to toxins than adults and need 

protecting. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Commenter Name: T.J. Blair 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0656 

EPA Comment ID: 20234 

EPA Comment Code: 6120 

 

Comment: It defies logic and common sense to dump toxic rocket fuel into or near drinking water 

sources. This practice will be especially harmful to people living near military bases. I urge you to 

SUPPORT OUR TROUPS, our children and others by NOT approving this regulation. 

Thomas J. Blair 592 W. 2nd St. Winston-Salem, NC 27101 

Response: EPA is not dumping toxic rocket fuel into or near water sources. Rather, EPA has 

determined to regulate perchlorate in drinking water. See response to comment code 6120. 

Commenter Name: Lynn Nadeau 

Commenter Organization: HealthLink 

EPA Document ID: EPA-HQ-OW-2008-0692-0657 

EPA Comment ID: 20235 

EPA Comment Code: 6120 

 

Comment: Rocket fuel has no place in drinking water. Incidence of cancer rises as we allow our 

environment to be degraded. Please, EPA, protect us! Live up to your title! 

Here in Massachusetts, we are well aware of the high rates of breast cancer on Cape Cod as well as 

the elevated amount of perchlorate in the water near the military base. 

Response: See response to comment code 6120. 

Commenter Name: Robin Mark Freeman 

Commenter Organization: Merritt College 

EPA Document ID: EPA-HQ-OW-2008-0692-0662 

EPA Comment ID: 20236 

EPA Comment Code: 6120 

 

Comment: Eric Burneson Office of Ground Water and Drinking Water Standards and Risk 

Management U.S. Environmental Protection Agency 

Dear Sir: 

We the undersigned are concerned that EPA's failure to regulate perchlorate, as well as its 

unprotective proposed health reference level, will adversely affect the health and development of 

hundreds of thousands, perhaps millions of American children. It has taken EPA years, with its 

extensive resources, to come to its conclusions. Its findings are complex and controversial. We 

cannot afford to have this decision rushed out the door, in the waning days of the current 

administration, without giving impacted communities sufficient time to comment. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 702 of 1099

Commenter Name: L. L. Schumacher 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0664 

EPA Comment ID: 20238 

EPA Comment Code: 6120 

 

Comment: Oct. 8, 2008 

Leonard L. Schumacher 16516 Denise Dr. Austin, Texas 78717 

U .S. Environmental Protection Agency Attn: Steve Johnson, EPA Administrator Arei1 Rios 

Building 1200 Pennsylvania Ave. N .W. Washington, DC 20460 Dear Mr. Johnson, 

I have read recently about the toxic rocket fuel ingredient (perchlorate) that has been found in 

public water supplies at 395 sites in 35 states, and that the EPA does not intend to rid it from the 

water. 

The levels found are high enough to affect thyroid function and pose developmental health risks, 

particularly for babies and fetuses according to some scientists. Great!!! 

Combine this toxin with all the other pesticides, insecticides, and the other many dangerous toxins 

and chemicals in our food supply, no wonder people are getting cancer. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: B. Raimondo 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0666 

EPA Comment ID: 20240 

EPA Comment Code: 6120 

 

Comment: STop!!!! Perchlorate in the drinking water!!! 

Response: See response to comment code 6120. 

Commenter Name: Tatjana and Jeremy Thomas 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0669 

EPA Comment ID: 20241 

EPA Comment Code: 6120 

 

Comment: Can't believe this has been going on for years. Is rocket fuel more important than 

human life? Of course we will just take some drugs to cover up the symptoms and keep doing what 

we are doing best, COVER UP THE BAD STUFF! God Bless America. 

Response: This is not a comment, a response is not necessary. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 703 of 1099

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0671 

EPA Comment ID: 20244 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPAâ€TMs refusal to regulate Perchlorate under 

the Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

Perchlorate is a chemical in rocket fuel that has been linked to thyroid problems in pregnant women, 

newborns and young children. The adverse effects of Perchlorate have not been extensively 

investigated. We do not know the full range of damage that this toxic chemical is having on our 

environment or our people. Nor have scientist looked at the synergistic effects of this poison, in 

combination with the thousands of other toxic substances known to be contaminating our drinking 

water. Not regulating this harmful chemical in our drinking water is unacceptable. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0671 

EPA Comment ID: 20246 

EPA Comment Code: 6120 

 

Comment: How many more people must die or be severely impaired before EPA takes it's job of 

protecting the environment and the people of this country seriously. These harmful chemicals are 

poisons. Too many have already been harmed. It appears to those of us, who've been harmed by 

toxic chemicals that the EPA has sold our lives and health away to special interests and chemical 

companies. Too many people have already been harmed. It appears to those of us, who've been 

harmed by environmental and consumer by-product toxins that the EPA has sold our lives and 

health away to special interests and chemical companies. How is this any different than slave 

trafficking or child prostitution? Your failure to protect us indicates a wanton disregard for our lives! 

I urge you to protect the environment, these current generations and the future generations of our 

country, in accordance with the Safe Drinking Water Act and protect all our health. Stop selling us 

out! 

Response: See response to comment code 6120. 

Commenter Name: P. Morello 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0674 

EPA Comment ID: 20247 

EPA Comment Code: 6120 

 

Comment: You MUST regualte perchlorate under the Safe water Drinking Act...please. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 704 of 1099

This chemical is found in rocket fuel & is a big safety issue for the public & our environment. It is a 

very dangerous chemical. What is wrong with you that you are NOT outlawing this chemical to be 

found in America's drinking water? 

Response: See response to comment code 6120. 

Commenter Name: Judy F. Rosenblith 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0675 

EPA Comment ID: 20248 

EPA Comment Code: 6120 

 

Comment: As a retired Professor whose specialty was child development and whose research 

involved newborns, I am particularly shocked by any lowering of standards for perchlorate that 

should be tightened. The effects on pregnant women and newborns are particularly important in 

informing my views. Please reconsider the current proposal. 

Sincerely, Judy F. Rosenblith Prof. Emerita, Wheaton College (MA) judyrosenblith@earthlink.net 

Response: See response to comment code 6120. 

Commenter Name: D. Manzullo 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0676 

EPA Comment ID: 20249 

EPA Comment Code: 6120 

 

Comment: How amazing that the health concerns of US Citizens continues to be put on the back 

burner by the Agencies that are supposed to be protecting us. 

With tens of thousands of Thyroid Cancers diagnosed every year, how can we not be more proactive in protecting our youth from unnecessary expense and health risks? 

Response: This is not a comment, a response is not needed. 

Commenter Name: Lisa Hampton 

Commenter Organization: Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0677 

EPA Comment ID: 20251 

EPA Comment Code: 6120 

 

Comment: No perchlorate in my drinking water! This decision is harmful to public health, and the 

EPA's refusal to to set a drinking-water standard for perchlorate is deplorable. As you know, 

perchlorate has been linked to thyroid problems in pregnant women, newborns and young children. 

As someone who suffers from thyroid problems, exhaustion which stopped my life for the 13 years 

it took me to figure out what was going on, I can personally attest to how serious thyroid problems 

can be. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 705 of 1099

Response: See response to comment code 6120. 

Commenter Name: Lisa Hampton 

Commenter Organization: Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-0677 

EPA Comment ID: 20252 

EPA Comment Code: 6120 

 

Comment: The Senate Environment and Public Works Committee has endorsed legislation 

requiring the EPA to set a federal standard for perchlorate and to monitor levels of the chemical in 

tap water. This I heartily support. We need to reduce the maximum safe levels for perchlorate as 

opposed to allowing them to be 15 times higher than they were in 2002. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0678 

EPA Comment ID: 20253 

EPA Comment Code: 6120 

 

Comment: I feel the stricter the standard on perchlorate levels in drinking water, the better. There 

is no ambiguity in the science that tells us that perchlorate is extremely harmful to the health of 

humans, especially to children. 

Response: See response to comment code 6120. 

Commenter Name: S. Smolen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0679 

EPA Comment ID: 20254 

EPA Comment Code: 6120 

 

Comment: Dear Sir, 

I am writing to you in response to the EPA's preliminary descision not to set a national maximum 

contaminant level for perchlorate (Docket ID # EPA-HQ- OW-2008-0068). I am a former resident 

of the San Gabriel Valley, California, and US citizen whose family was exposed to contaminated 

groundwater containing perchlorate for a significant length of time. I was exposed to perchlorate at 

elevated levels through drinking water and also now suffer Hashimoto’s thyroid disease. Following 

discovery of the profound levels of contamination in the San Gabriel Valley, I have been very 

discouraged and disappointed in the apparent lack of concern for residents whose health has 

potentially been affected by long-term, historic, contamination. I appreciate the efforts that have 

since been made to clean up the toxins and to protect the drinking water of current residents, but 

that does nothing for residents that have already been exposed. In addition, I now reside in a state 

that does not have a MCL for perchlorate despite having known perchlorate releases. I am 

concerned for my children as well as the public's safety. It is for these reasons that I am very 

concerned about the EPA’s preliminary decision not to set a maximum contaminant level for 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 706 of 1099

perchlorate. I worry that we are facing another situation where we will be looking back wishing more 

appropriate safety measures had been implemented. 

Response: See response to comment code 6120. 

Commenter Name: Marcia Willhite 

Commenter Organization: Illinois Environmental Protection Agency 

EPA Document ID: EPA-HQ-OW-2007-0068-0155 

EPA Comment ID: 20257 

EPA Comment Code: 6120 

 

Comment: The Illinois Environmental Protection Agency ("EPA") recommends that the Agency 

reconsider its position of not regulating perchlorate, 2,4-dinitrotoluene, and 2,6-dinitrotoluene under 

the National Primary Drinking Water Regulation. 

Response: This comment is outside of the scope of this action, no response necessary. 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0162 

EPA Comment ID: 20267 

EPA Comment Code: 6120 

 

Comment: Perchlorate 

Perchlorate is a very important issue for the drinking water community, and the perchlorate options 

detailed in the May 1st Federal Register notice raise many complex issues. Perchlorate provides EPA 

with a critical opportunity to appropriately implement the standard setting provisions of the 1996 

SDWA amendments and the CCL/UCMR process. Additionally, there has been significant public 

interest generated by press coverage and subsequent interest by legislative bodies in certain states 

and at the federal level. 

Building upon our position previously communicated to EPA in letters on February 2, 2005 and 

May 27, 2005, we recommend that EPA now make the decision to regulate perchlorate. AWWA 

believes that EPA has enough information to make a positive regulatory determination, and then to 

move forward with a proposed perchlorate regulation consistent with the requirements of the Safe 

Drinking Water Act. 

We make this recommendation for the following reasons, absent any one of which we might make a 

different recommendation: 

1. The National Research Council (NRC) and the Centers for Disease Control and Prevention 

(CDC) have found that perchlorate may have an adverse impact on the health of persons. 

2. Perchlorate is known to occur in public water supplies in a number of states. 

3. While occurrence data does not suggest that perchlorate occurs at levels of public health concern 

in the vast majority of public drinking water supplies and the population at risk appears to be small, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 707 of 1099

that group does include a sensitive subpopulation (pregnant women and developing fetuses) of 

significant concern. 

4. The Greer data and the Reference Dose (RfD) recommended by the National Research Council 

(NRC) now make it possible for EPA to determine a protective level for perchlorate with a degree 

of confidence appropriate to a national primary drinking water regulation. 

5. There are appropriate and reliable analytical methods for utilities and others to measure 

perchlorate concentrations in public water supplies, as documented by UCMR sampling, and 

laboratory capacity is not an issue. 

6. A number of states are moving to regulate perchlorate and a patchwork of different regulations 

will confuse the public and the regulated community. And 

7. Strong anecdotal data suggests that the lack of a perchlorate MCL has impeded a number of 

cleanups at hazardous waste sites. Cleanup at these sites could benefit public water suppliers, among 

others. 

Response: See response to comment code 6120. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0166 

EPA Comment ID: 20275 

EPA Comment Code: 6120 

 

Comment: The notice also discusses perchlorate and does not provide a regulatory determination 

for this contaminant despite the availability of extensive data and high public concern. Because of 

the high public concern there is also high political interest. As local stewards of public health, we 

believe that if perchlorate presents a public health risk, then EPA should establish a maximum 

contaminant level for it. AMWA believes strongly in the regulatory process outlined in the 1996 

Amendments. In the case of perchlorate, AMWA believes that the information available to the 

agency clearly points to a determination to regulate. 

It appears that the agency has deferred the decision on perchlorate based solely on wanting a more 

accurate determination of the relative source contribution that might be attributable to drinking 

water. The notice states that, absent that information, a determination whether setting a national 

primary drinking water standard would provide a meaningful opportunity to reduce risk for people 

served by public water systems cannot be made. 

Response: See response to comment code 6120. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0166 

EPA Comment ID: 20277 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 708 of 1099

Comment: At least nine states have addressed perchlorate through standards, health advisories, 

health based guideline levels, public advisories or other means. Utilities in states where no action has 

been taken face public perception and confidence problems at a minimum. EPA faces these same 

problems through continued inaction. A federal standard is needed in place of inconsistent state 

requirements. 

AMWA urges EPA to keep in mind that a regulatory determination is the start of the regulatory 

process and not the end. Additional data is always gathered during the process. The final regulatory 

construct and requirements will be based on this data. All presently available data indicate that a 

positive determination is appropriate. Therefore AMWA believes that it is time for the regulatory 

process to begin. EPA can start this process outside the formal regulatory determinations and 

should do so. At minimum, a positive final determination should be made along with the 

determinations not to regulate 11 contaminants proposed in the present notice based on present 

data, and any additional information developed over the next several months while the agency’s 

regulatory determinations are finalized. 

If you have any questions about our comments, please do not hesitate to contact me or Erica Brown 

at 202-331-2820. 

Sincerely, Diane VanDe Hei Executive Director Cc: Cynthia Dougherty, OGWDW 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1130 

EPA Comment ID: 20290 

EPA Comment Code: 6120 

 

Comment: it is crucial to the health of our nation that we monitor perchlorate levels in our drinking 

water! 

Response: See response to comment code 6120. 

Commenter Name: Glen Shull 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1132 

EPA Comment ID: 20291 

EPA Comment Code: 6120 

 

Comment: I don't know how much percholate is in our water but if it is in it we should regulate it. 

We did not regulate sub-prime loans, allowed people to submit loans to people who could not 

afford them and look what happened. If people are in danger of being sick from percholate, let's 

disallow it to be even close to illness causing levels. I teach tennis in Florida and drink a gallon of 

water a day, plus juices. 

Glen shull 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 709 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1134 

EPA Comment ID: 20292 

EPA Comment Code: 6120 

 

Comment: Do not permit perchlorate in water. Not healthful for babies, children or adults. If we 

are not to buy bottled water because of the environmental impact of plastic bottles then we need 

clean safe tap water to drink. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1139 

EPA Comment ID: 20293 

EPA Comment Code: 6120 

 

Comment: On October 10, the EPA announced its preliminary decision not to regulate perchlorate 

in drinking water. EPA has requested comments from the public before making a final decision. Ask 

the Administration and the EPA to reverse this finding and regulate perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1141 

EPA Comment ID: 20294 

EPA Comment Code: 6120 

 

Comment: I am writing to urge the EPA to regulate perchorate in our drinking water supplies. This 

is a chemical that has been proven to cause health problems, particulary in young children, and it 

crucial that we regulate it. 

Thank you very much 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1144 

EPA Comment ID: 20295 

EPA Comment Code: 6120 

 

Comment: Do not allow perchlorate in our water!! 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 710 of 1099

Response: See response to comment code 6120. 

Commenter Name: C. McFall 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1147 

EPA Comment ID: 20296 

EPA Comment Code: 6120 

 

Comment: Perchlorate is only one of a cascade of foreign substances making its way into our 

drinking water. We are constantly learning of new, harmful substances whose interaction with our 

bodies and with other contaminates is unknown. The ONLY way we can preserve quality of our 

health as a nation is to ensure these foreign substances are not consumed by any of us. The EPA is 

supposed to PROTECT us from contamination, not facilitate it. This is our health, our future and 

our children we are talking about - not a group of hypothetical 'percentage of exposure' risks. Please 

wake up and start seeing our environment for the mess we have made it and help us clean it up, not 

add to the problem because someone talked you into it. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1152 

EPA Comment ID: 20297 

EPA Comment Code: 6120 

 

Comment: Please reverse decision to allow perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Amy Cobaugh 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1153 

EPA Comment ID: 20298 

EPA Comment Code: 6120 

 

Comment: Please regulate perchlorates in our drinking water. As a citizen, I am very concerned 

about the health affects on my children, who are especially vulnerable to pollutants. 

Thanks, 

Amy Cobaugh San Mateo County, CA 

Response: See response to comment code 6120. 

Commenter Name: Rebecca Teal 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1157 

EPA Comment ID: 20299 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 711 of 1099

EPA Comment Code: 6120 

 

Comment: Please keep rocket fuel in my drinking water. I like the way it makes my third eye glow. 

Regards, Rebecca Teal 

Response: This is not a comment; no response is necessary. 

Commenter Name: J. Vasconcellos 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1158 

EPA Comment ID: 20300 

EPA Comment Code: 6120 

 

Comment: Its time to be proactive, as well as foresighted. Whats easier and more desirable to treat: 

perchlorate in our drinking water or askewed thyroid disease in our children? Think the Future! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1162 

EPA Comment ID: 20301 

EPA Comment Code: 6120 

 

Comment: We Minnesota voters just announced loud and clear in yesterday's vote that we're willing 

to pay higher taxes in return for increased protection of our water, air, and other natural resources. 

Let's bring our regulatory protection up to speed. Monitor Perchlorates. 

Response: See response to comment code 6120. 

Commenter Name: G. A. Bagazinski 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1166 

EPA Comment ID: 20302 

EPA Comment Code: 6120 

 

Comment: No Percholate in Drinking Water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1167 

EPA Comment ID: 20303 

EPA Comment Code: 6120 

 

Comment: how about trying to keep perchlorate to a minimum level in our drinking water, like 

around none would be good, yes? 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 712 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1169 

EPA Comment ID: 20304 

EPA Comment Code: 6120 

 

Comment: Don't see any reason that we should have Perchlorate in our water. Please consider 

limiting it. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1171 

EPA Comment ID: 20305 

EPA Comment Code: 6120 

 

Comment: Reverse your ruling on perchlorate. No one wants to drink something that is tainted 

with fuel ingredients The environmental impact of increased bottled water consumption should be a 

factor in your consideration. Every effort should be made to increase the purity of our drinking 

water, so we can help reduce the environmentally damaging, excessive consumption of bottled 

water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1177 

EPA Comment ID: 20306 

EPA Comment Code: 6120 

 

Comment: I strongly believe the U.S. Environmental Protection Agency must reverse its 

preliminary determination on setting a regulation for perchlorate in drinking water. Perchlorate is a 

serious concern health-wise, and I do not want it in the water I am drinking. 

Response: See response to comment code 6120. 

Commenter Name: Louise McEvers 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1180 

EPA Comment ID: 20307 

EPA Comment Code: 6120 

 

Comment: As a citizen with low thyroid, I urge the U.S. Environmental Protection Agency to 

reverse its preliminary determination on setting a regulation for perchlorate in drinking water. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 713 of 1099

Perchlorate contamination is a national problem that could impact many Americans. 

Please reconsider your position. 

Louise McEvers Austin, TX 78729 

Response: See response to comment code 6120. 

Commenter Name: K. Moreland 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1183 

EPA Comment ID: 20308 

EPA Comment Code: 6120 

 

Comment: Percholate is a dangerous chemical and needs to be kept out of our drinking water. You 

must regulate this dangerous chemical 

Response: See response to comment code 6120. 

Commenter Name: Deb Arnason 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1184 

EPA Comment ID: 20309 

EPA Comment Code: 6120 

 

Comment: Please do not allow percolate in our drinking water. Sadly. the EPA has deteriorated 

over the past 8 years. With our new President, I hope we can look forward to your PROTECTION 

that has been lacking by regulating this hazardous chemical as well as many others in our air, water 

and food supplies. Thank you for returning to sanity. Please help by doing the job we used to trust 

you for. 

Deb Arnason 12 Dill St, Alva, FL 33920 386-288-4454 diamondteldeb@aol.com 

Response: See response to comment code 6120. 

Commenter Name: W. Mcclure 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1190 

EPA Comment ID: 20310 

EPA Comment Code: 6120 

 

Comment: Please reverse your decision and keep perchlorate out of the water supply. The public 

health takes precedence over business convenience and cost. 

Response: See response to comment code 6120. 

Commenter Name: C. Rongstad 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 714 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1191 

EPA Comment ID: 20311 

EPA Comment Code: 6120 

 

Comment: I ask the EPA to reverse its decision not to regulate perchlorate in drinking water. Why 

not regulate a chemical that has health impacts at low levels and is detectable in our drinking water? 

Please consider the lack of regulation as harmful to the public and include perchlorate in drinking 

water regulations. 

Response: See response to comment code 6120. 

Commenter Name: T. J. Sanders 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1192 

EPA Comment ID: 20312 

EPA Comment Code: 6120 

 

Comment: Let us do what it takes to save our environment and our planet. It is the only home we 

have. We are becoming over populated, and it is no longer acceptable to add toxins to our ater and 

air. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1195 

EPA Comment ID: 20313 

EPA Comment Code: 6120 

 

Comment: Do not put perchlorate in our drinking water. 

Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Frances Ann Leary 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1209 

EPA Comment ID: 20314 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

A national primary drinking water regulation would provide a meaningful opportunity to protect 

public health. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 715 of 1099

Take the precautionary approach, or we will all pay later. It's harder to remove contaminants and try 

to make ammends with families impacted both emotionally and financially by the ramifications of 

toxics in their water. Now is the time to be a leader on this and other critical environmental issues. 

Sincerely, Frances AnnLeary 

Response: See response to comment code 6120. 

Commenter Name: L. Thorpe 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1221 

EPA Comment ID: 20315 

EPA Comment Code: 6120 

 

Comment: Please keep chemicals out of our water. It is harming my families health and yours. 

Response: See response to comment code 6120. 

Commenter Name: Shawn Taylor 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1231 

EPA Comment ID: 20335 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. I believe this is urgent for 

public safety. 

Sincerely, 

Shawn Taylor 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1232 

EPA Comment ID: 20336 

EPA Comment Code: 6120 

 

Comment: As a concerned citizen with a family living by a major river and atop an already 

imperiled aquifer, I am distraught that EPA is even considering not regulating perchlorate levels in 

the water supply. How can my government be so unconcerned for its citizens' well-being? 

Perchlorate is a component in rocket fuel, and the science shows that even in low amounts it can be 

a threat to our health. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 716 of 1099

It is no favor to industry for the EPA not to set safety levels and monitor water for the presence of 

perchlorate. Should contamination at unsafe levels occur, the damage to the health of even a few 

citizens, much less to the large numbers who might be affected in any significantly populated area, 

would be a terrible blow to the industry as well. 

It should be very clear that wise regulation is good for everyone. This is EPA's obligation, the very 

reason for your existence. This is not a quasi-market situation in which if one party fails, someone 

else will step in. EPA is our last best defense against man-made environmental hazards. We the 

citizenry are counting on you. 

Response: See response to comment code 6120. 

Commenter Name: Patricia A. Gozemba 

Commenter Organization: Salem Alliance for the Environment (SAFE) 

EPA Document ID: EPA-HQ-OW-2008-0692-1234 

EPA Comment ID: 20337 

EPA Comment Code: 6120 

 

Comment: We have seen our water supply for the City of Salem, MA jeopardized at Wenham Lake. 

We believe that the EPA should hold the line on weakening standards. I urge the U.S. 

Environmental Protection Agency to reverse its preliminary determination on setting a regulation 

for perchlorate in drinking water. Perchlorate contamination is a nationwide problem and has health 

impacts at lower levels than previously thought; a national primary drinking water regulation would 

provide a meaningful opportunity to protect public health. The EPA should hold off on making 

determinations such as this until the new administration takes office. 

Dr. Patricia A. Gozemba 

Salem, Massachusetts 

Response: See response to comment code 6120. 

Commenter Name: Tony Dewalt 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1235 

EPA Comment ID: 20338 

EPA Comment Code: 6120 

 

Comment: please remove rocket fuel, flare chemical from our waters. lets keep usa,s waters ahead 

of most of the worlds in drinking quality thank you tony dewalt 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1237 

EPA Comment ID: 20339 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 717 of 1099

 

Comment: I have a chronic health condition and live not far from launch pads. The people of the 

community have long time wondered if the contaminants to which we are exposed are regulated or 

responsible for health issues. I am afraid as are those who read about perchlorates . We know they 

are not good for us! Please reverse the decision not to monitor this chemical and let us know you 

truly do care about the health of the public. It is critical to our childrens growth and the general 

health of our people. 

Response: See response to comment code 6120. 

Commenter Name: M. Musgrave 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1240 

EPA Comment ID: 20340 

EPA Comment Code: 6120 

 

Comment: "Researchers at the Centers for Disease Control and Prevention (CDC) have just 

released findings that show that American women -- and especially women with low iodine intake -- 

are at risk of hypothyroidism due to common exposure to the toxin perchlorate. " I'm not making 

this up. Check the facts. Perchlorate must be regulated to protect us--that's your job! If you want to 

keep it do it better and reverse this ruling. Our new administration will be sure to make you 

accountable for your responsibilities to The People! 

Response: See response to comment code 6120. 

Commenter Name: T. Lampert 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1241 

EPA Comment ID: 20341 

EPA Comment Code: 6120 

 

Comment: No relaxing of standards for water purity. No percholates inthe water!!!!!!! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1246 

EPA Comment ID: 20342 

EPA Comment Code: 6120 

 

Comment: I am concerned about rocket fuel being in our water supply and wouldn't like it to be in 

it, please. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 718 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-1249 

EPA Comment ID: 20343 

EPA Comment Code: 6120 

 

Comment: Please test for perchlorate in our drinking water! 

Response: This regulatory action does not affect testing requirements for perchlorate. Please See 

response to comment code 6120. 

Commenter Name: Cara Cordoni 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1250 

EPA Comment ID: 20344 

EPA Comment Code: 6120 

 

Comment: Please protect our drinking water. Test for and protect us from percholate! Jet fuel is 

not food, not nutrition, not health and does not belong in our water or bodies. Please protect our 

babies, our children, our elderly. Do not make the same kind of mistake the FDA made with the 

pesticide that is killing our bees - protect us from the beginning. 

Cara Cordoni 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1262 

EPA Comment ID: 20345 

EPA Comment Code: 6120 

 

Comment: 3M has been dumping this chemical and several others in our aquifer for years. At first 

they said there were no negative effects from it, but later I believe concerns about cancer, possibly, 

have been raised. 

At any rate, chemicals other than minerals supplied naturally are not a desirable item in potable 

water. 

Please take care of this. 

Thanks. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1264 

EPA Comment ID: 20346 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 719 of 1099

 

Comment: What? Is not the the EPA the Environmental PROTECTION Agency? What is more 

important than monitoring and regulating what poisonous chemicals might enter our water sources? 

And what better motivation is needed than to protect our children? Our seeds of the future! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1265 

EPA Comment ID: 20347 

EPA Comment Code: 6120 

 

Comment: Please do your job and keep our water safe. Keep Perchlorate out of the water 

Response: See response to comment code 6120. 

Commenter Name: N. Henderson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1266 

EPA Comment ID: 20349 

EPA Comment Code: 6120 

 

Comment: As the mother of an infant, I urge the EPA to reconsider its position on the regulation 

of perchlorate in drinking water. Each and every contaminant in our public water supply jeopardizes 

the health of the citizens of this country, particularly are most vulnerable population--infants and 

children. Ultimately, a decision not regulate a chemical that we ingest has high financial cost when 

one 1 in 4 Americans will develop cancer during their lifetime. Please consider this factor when 

assessing this decision. 

Response: See response to comment code 6120. 

Commenter Name: Robert L. Oldershaw 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1268 

EPA Comment ID: 20350 

EPA Comment Code: 6120 

 

Comment: Please get with the new program: emphasis on protecting the ENVIRONMENT rather 

than on protecting the excess profits of influencial corporations. 

Please ask yourselves whether you need to regain some integrity and self-esteem before you leave for 

new jobs. 

Thanks, 

Robert L. Oldershaw 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 720 of 1099

Response: See response to comment code 6120. 

Commenter Name: Nancy B. Kurtz 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1269 

EPA Comment ID: 20351 

EPA Comment Code: 6120 

 

Comment: Coming from a family that has a tendency toward environmentally triggered diseases I 

want to tell you to take responsibility and mandate the perchlorate out of our drinking water. We 

have only begun to realize how many diseases are triggered by contaminants and need to nip this 

track in the bud. This is a can of worms you don't want to be a part of opening. 

Nancy B.Kurtz 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1271 

EPA Comment ID: 20352 

EPA Comment Code: 6120 

 

Comment: I am speaking against the EPA's preliminary decision not to regulate perchlorate in 

drinking water. I'd like to believe the EPA is working primarily to protect the public's health and not 

catering to big industry's concerns that regulations hamper their ability to make money. The USA 

needs to be a world leader in protecting the environment with very stringent rules. 

Response: See response to comment code 6120. 

Commenter Name: Amy Rice-O'Rourke 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1274 

EPA Comment ID: 20353 

EPA Comment Code: 6120 

 

Comment: Dear Ones, 

As a working Mother who grew up swimming and fishing in Lake St. Clair, & one who I takes our 

own kids there all summer, I am very concerned about these new laxxed regulationsabout the 

amount of perchlorate in our drinking water. What is an exceptable amount of poisin? How long 

will it be until my children or their children show the effects of these pollutants? I urge the U.S. 

Environmental Protection Agency to reverse its preliminary determination on setting a regulation 

for perchlorate in drinking water. Perchlorate contamination is a nationwide problem and has health 

impacts at lower levels than previously thought; a national primary drinking water regulation would 

provide a meaningful opportunity to protect public health. As you make these determinations, please 

bear in mind my 7 & 9 year old boys, their potential children and the hundreds of thousands of 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 721 of 1099

other children who grow up all around the Great Lakes States & Canada and we deserve clean water 

to drink. We have to protect their legacy as well as their health. 

Sincerely, 

Amy Rice-O'Rourke 

Response: See response to comment code 6120. 

Commenter Name: J. M. Meyerson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1275 

EPA Comment ID: 20354 

EPA Comment Code: 6120 

 

Comment: Please work hard keep contaminants like Perchlorate out of our drinking water. As 

citizens, we depend on you to protect us all. 

Thank you, 

Response: See response to comment code 6120. 

Commenter Name: C. W. Doppler 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1280 

EPA Comment ID: 20355 

EPA Comment Code: 6120 

 

Comment: Clean water is a basic human right and a basic government responibility. As a citizen, I 

demand that you regulate perchlorate contamination in our drinking water. 

Christina W Doppler 

Crown Point IN 

Response: See response to comment code 6120. 

Commenter Name: Gary Kropilak 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1281 

EPA Comment ID: 20356 

EPA Comment Code: 6120 

 

Comment: Gary Kropilak 

16 Peek St 

Rochelle Park, NJ 07662 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 722 of 1099

To whom it may concern, 

Your decision to allow percholate to remain in our drinking water is unacceptable. Our limited 

supply of drinking water must be protected and free of all harmful contaminates. Even miniscule 

amounts of percholate can threaten the health of fetuses, infants, teens and adults. I implore you to 

REVERSE your decision not to regulate percholate. Please protect us. 

Thank You, 

Gary Kropilak 

Response: See response to comment code 6120. 

Commenter Name: S. Brown 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1284 

EPA Comment ID: 20357 

EPA Comment Code: 6120 

 

Comment: I'm writing to ask the agency to reconsider its decision on the need to regulate 

perchlorate levels in drinking water. Given its widespread contamination (37+ states) and thyroid 

effects at low concentrations, particularly in utero, it is vital that the agency moves to protect public 

health. 

Response: See response to comment code 6120. 

Commenter Name: G. Guthmiller 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1285 

EPA Comment ID: 20358 

EPA Comment Code: 6120 

 

Comment: Please regulate the perchlorate level in our drinking water. We do not need any 

chemicals dissolved in our water. We may find in the future that this chemical has many hazardous 

risks for humans. Please don't poison our future generations. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Susan D. Snyder 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1288 

EPA Comment ID: 20359 

EPA Comment Code: 6120 

 

Comment: Re: Drinking water standards & Perchlorate: I find it ironic that the agency responsible 

for the safety and protection of both the American public and the national environment would 

consider that any amount of perchlorate - which is not a naturally occurring chemical - has an 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 723 of 1099

acceptable level in the potable water of any mammal, whether human person or animal. To set any 

sort of standard/acceptable amount for percholorate presence is immoral, should never become 

legal and is, in the event, reprehensible. I understand that maintaining pure (perchlorate-free) water 

carries a cost: but it is nothing to the deep harm the chemical does to those who have no option but 

to drink it. Please, take the "high road" of consumer and environmental protection - in accordance 

with your mandate - and do not institutionalize the further poisoning of our water system. I would 

appreciate a written acknowledgment of my comment. 

Susan D. Snyder 8628 

Garfield Street 

Bethesda, MD 208187 

sue_snyder@verizon.net 

Response: See response to comment code 6120. EPA acknowledges your request for a reply to 

your comment; however, EPA is unable to reply directly to all comments submitted. 

Commenter Name: J. Kayle 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1291 

EPA Comment ID: 20360 

EPA Comment Code: 6120 

 

Comment: Of course you need to regulate whether or not perchlorate is getting into our water 

supply! Don't be ridiculous. Please. 

Response: See response to comment code 6120. 

Commenter Name: Greg Swanson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1293 

EPA Comment ID: 20361 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

On October 10, the EPA announced its preliminary decision not to regulate perchlorate in drinking 

water. I cannot understand why your agency would ever consider not regulating this contaminate. 

The purpose of your agency is to be the watchgard for the public in Protecting us from harmful 

substances. You need to side with the publics best interest in mind. If this causes manufacturers and 

industry to incur costs then they need to be responsible and include them in their cost of doing 

business just like all other repsonsible companies and manufactures. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 724 of 1099

Perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; A national primary drinking water regulation would provide a meaningful 

opportunity to protect public health. 

Perchlorate is a harmful chemical used in rocket fuel, flares, and explosives. Perchlorate, even in 

small amounts, can impair the thyroid gland, which controls growth, development and metabolism. 

Developing fetuses, infants and children with thyroid impairment may suffer mental retardation, loss 

of hearing and speech or deficits in motor skills. EPA agrees that perchlorate has been found in 395 

sites in 37 states, including 153 public water systems serving over 20 million people. Some estimates 

are even higher. 

Reverse your preliminary determination and responsibly regulate this potentially harmfull substance. 

Thank You 

Greg Swanson 

Response: See response to comment code 6120. 

Commenter Name: Kate Mendeloff 

Commenter Organization: University of Michigan, Ann Arbor 

EPA Document ID: EPA-HQ-OW-2008-0692-1294 

EPA Comment ID: 20362 

EPA Comment Code: 6120 

 

Comment: I am a private citizen who has great concern about the potential pollution of our 

drinking water by perchlorate. Please be responsible for the general welfare and make this illegal! 

Kate Mendeloff, University of Michigan, Ann Arbor 

Response: See response to comment code 6120. 

Commenter Name: Lisa Stewart 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1300 

EPA Comment ID: 20363 

EPA Comment Code: 6120 

 

Comment: Please reverse your decision and regulate perchlorate in drinking water. Isn't potable 

drinking water a priority? 

You need to shed your "too little too late" image of post 911 and show Americans that you are 

doing your job to protect us from contaminates either in the air or water. 

Your attention to the this is vital to the well being of countless Americans. 

Most sincerely, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 725 of 1099

Lisa Stewart 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1301 

EPA Comment ID: 20364 

EPA Comment Code: 6120 

 

Comment: I first read about perchlorate in the newspaper several years ago when it was discovered 

to be on organic lettuce grown in California! PLEASE reverse your preliminary determination on 

setting a regulation for perchlorate in drinking water. This is a national problem - clean it up! 

Response: See response to comment code 6120. 

Commenter Name: J. Seegmiller 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1302 

EPA Comment ID: 20365 

EPA Comment Code: 6120 

 

Comment: Keep perchlorate out of our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Lisa Quartararo 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1303 

EPA Comment ID: 20366 

EPA Comment Code: 6120 

 

Comment: Perchlorate should be federally regulated just like any other chemical that has the 

potential to harm people or the planet. I don't understand what you are thinking! 

Sincerely, 

Lisa Quartararo 

Colonia, NJ 07067 

Response: See response to comment code 6120. 

Commenter Name: Greta Mackenzie 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1307 

EPA Comment ID: 20367 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 726 of 1099

 

Comment: since my drinking water comes from a surficial aquifer within a watershed affected by 

miami international airport, and concievable by the old aerojet facility, I would appeciate knowing it 

is safe to drink. Unfortunately the EPA dosnt inspire the confidence it used to under the Clinton 

administration. As far as I'm concerned, the more regulation on MCL's for water (and while we are 

at it air and food) the better! 

greta Mackenzie PhD. 

Response: This is outside of the scope of this effort, no response is necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1309 

EPA Comment ID: 20368 

EPA Comment Code: 6120 

 

Comment: Please reverse your action to not regulate perchlorate in our drinking water. It's absurd 

that you would even consider allowing it in our drinking water----I mean you have to drink this 

water as well. Lets use some common sense. 

Response: See response to comment code 6120. 

Commenter Name: L. Doggett 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1310 

EPA Comment ID: 20369 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: M. Hough 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1312 

EPA Comment ID: 20370 

EPA Comment Code: 6120 

 

Comment: I am deeply concerned with regard to articles I have read regarding perchlorate in our 

drinking water. This is an issue I feel needs to be addressed by the EPA. It clearly is a harmful 

chemical which can impair the thyroid gland and affect fetuses, infants and children. This is 

dangerous even in the smallest amounts. The EPA has decided not to move forward to regulate 

perchlorate in drinking water which possibly will be a big mistake. You have your findings and you 

must act accordingly. This contamination in drinking water is nationwide and not to take the proper 

measures to ensure the safety of our drinking water would be harmful in the long run. Please 

reconsider and take the precautionary measures. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 727 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1313 

EPA Comment ID: 20371 

EPA Comment Code: 6120 

 

Comment: I've been drinking water for a long time. My family drinks water. My pregnant daughter 

is passing the contents of the water she drinks on to her unborn child. Moreover, I believe the 

agents of our government responsible for water quality oversight drink water. In short, we all have a 

stake in keeping our water sources pure. Please keep faith with the trust we have put in you. Keep 

perchlorate out of our water (yours and mine). Reverse this decision. 

Response: See response to comment code 6120. 

Commenter Name: A. Crane 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1317 

EPA Comment ID: 20372 

EPA Comment Code: 6120 

 

Comment: Attention EPA Officials: I don't want perchlorate in our water systems. What would 

Ralph Nader say if he heard you were stopping your testing of this dreadfully harmful chemical in 

our drinking water? I think he'd say "get back on it!" Please help keep our waters safe for all the 

plants, animals and people who can't live without it. 

Thank you, 

A. Crane 

Response: See response to comment code 6120. 

Commenter Name: Christy Anderson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1318 

EPA Comment ID: 20373 

EPA Comment Code: 6120 

 

Comment: To whom it may or may not concern, 

I strongly urge the U.S. Environmental Protection Agency to reverse its preliminary determination 

on setting a regulation for perchlorate in drinking water. Perchlorate contamination is a nationwide 

problem and has health impacts at lower levels than previously thought. It is unethical and 

inappropriate to allow toxic substances in our drinking water; however, a national primary drinking 

water regulation would provide a meaningful opportunity to protect public health. Please protect our 

health and the health of our children!! 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 728 of 1099

Christy Anderson 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1319 

EPA Comment ID: 20374 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. E.P.A. to reverse its preliminary determination on setting a regulation for 

perchlorate in drinking water as this can be very hazardous to large groups of our population and 

cannot be ignored. 

Response: See response to comment code 6120. 

Commenter Name: Heidi Washburn 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1322 

EPA Comment ID: 20375 

EPA Comment Code: 6120 

 

Comment: To the EPA, As a citizen, parent, grandparent, and teacher, I strongly urge the EPA to 

reverse its decision NOT to regulate perchlorate, rocket fuel, in our nations water and drinking 

water. Perchlorate is a harmful chemical whose devastating effects on humans and animals will last 

generations. As a government organization created to protect our environment, I believe it is your 

moral duty to act now to insure that perchlorate does not make its way into the water. PLEASE 

ACT NOW --- KEEP PERCHLORATE OUT OF AMERICA'S WATER. 

Respectfully submitted, 

Heidi Washburn 

4615 Daventry Place 

Valrico, FL 33596 

Response: See response to comment code 6120. 

Commenter Name: Frank Blaskowitz 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1323 

EPA Comment ID: 20376 

EPA Comment Code: 6120 

 

Comment: The EPA regulates a number potential health hazards. Perchlorate contamination is real 

and must be addressed. I urge the EPA to regulate this contaminant as quickly as possible. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 729 of 1099

Thank You, 

Frank Blaskowitz 

Response: See response to comment code 6120. 

Commenter Name: Robert Prato 

Commenter Organization: Bucks County HIRT 

EPA Document ID: EPA-HQ-OW-2008-0692-1327 

EPA Comment ID: 20377 

EPA Comment Code: 6120 

 

Comment: I would strongly urge the EPA to reconsider the perchlorate regulation for drinking 

water standards. I have experience with these chemicals first hand (I am a Captain on a regional 

Hazardous Material response team), and I have a great understanding of the short and long term 

effects of this type of chemical. Even minute amounts of this can cause harm to humans and 

animals alike. Please give due consideration to creating a standard for these chemicals. 

Thank you. 

Robert Prato Capt. 

89-1 Bucks County 

HIRT Bucks County, PA 

Response: See response to comment code 6120. 

Commenter Name: Maureen Roddy 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1328 

EPA Comment ID: 20378 

EPA Comment Code: 6120 

 

Comment: Keep rocket fuel out of our drinking water!!! Our children are suffering from an 

epidemic of frontal lobe disorders -- autism is just one of them. Clean up our water and keep 

neurotoxins out. thank you. 

Maureen Roddy 

978 Van Auken Circle 

Palo Alto, CA 94303 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 730 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1329 

EPA Comment ID: 20379 

EPA Comment Code: 6120 

 

Comment: Safe Drinking Water is one of the main indicators of a developed country. Allowing 

percholate do go untested or regulated in our country's municipal waters is a mistake - one that 

every citizen will unknowingly make when they reach for a glass of tap water. With so much effort 

being made to turn people away from the fallacy of bottled water, why would we give people any 

more reason to doubt their local water sources? 

Please consider testing water for percholate and making sure levels are well below the permissible 

amount! 

Response: This regulatory action does not affect testing requirements for perchlorate in local 

jurisdictions. Please see the response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1333 

EPA Comment ID: 20380 

EPA Comment Code: 6120 

 

Comment: I urge the EPA to reverse its decision on Perchlorate. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: John and Barb and family Harburg 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1334 

EPA Comment ID: 20381 

EPA Comment Code: 6120 

 

Comment: Please keep perchlorate out of the water. 

Thank you 

John and Barb Harburg and family 

Response: See response to comment code 6120. 

Commenter Name: Julie Seifert 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1336 

EPA Comment ID: 20382 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 731 of 1099

Comment: Please urge tj=he EPA to reverse it's preliminary determination on setting a regulation 

for permitting perchlorate in our drinking water. No levels are safe and we need to be 

protected!!!!!!!!!!!!! 

Julie Seifert 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1337 

EPA Comment ID: 20383 

EPA Comment Code: 6120 

 

Comment: Regulate Perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: D. Puyanic 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1339 

EPA Comment ID: 20384 

EPA Comment Code: 6120 

 

Comment: You must regulate perchlorate - an ingredient in rocket fuel. You must reverse this 

finding and regulate perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Julia Burch 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1340 

EPA Comment ID: 20385 

EPA Comment Code: 6120 

 

Comment: I do not want my drinking water standards loosened, especially when it comes to 

perchlorate. I understand that President Bush is trying to undo many important regulations that 

protect public health and our environment in his last few days in office. But EPA serves the 

American people, not just the President. EPA's job is to protect the public from harmful exposures 

whether acute or chronic. As well as to protect the environment for future generations. In the past 

eight years EPA has fallen down on this job. Regulations should be just as difficult to undo as they 

are to put in place to prevent politics and industry from having inappropriate influence on our 

nation's environmental health. Keep perchlorate out of our water. In addition, EPA needs to 

develop standards for atrizine as well. Pesticides should not be in our water either. And if the 

technology does not exist to remove these chemicals from drinking water then they should be 

banned from use or production. 

Private Citizen Julia Burch 846 32nd Street Sarasota, Florida 34234 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 732 of 1099

Response: Regarding regulation of perchlorate, See response to comment code 6120. Regarding 

regulation of atrazine, this is outside of the scope of this effort. 

Commenter Name: Chip Thomas 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1344 

EPA Comment ID: 20386 

EPA Comment Code: 6120 

 

Comment: Please reverse the decision to not regulate perchlorate. It needs to be regulated due to its 

potential harm. 

Chip Thomas Tampa, Fl 813-238-0437 

Response: See response to comment code 6120. 

Commenter Name: Aaron Smith 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1346 

EPA Comment ID: 20387 

EPA Comment Code: 6120 

 

Comment: To Whom It May Concern: 

The decision to put into place measures to regulate perchlorate in drinking water rest on the EPA's 

assessment of potential reduction of public health risk caused by the pollutant. It seems logical to 

me, and I hope to you, that if there exists ANY risk, or even the possibility of a risk to an population 

of American people, no matter how small, that regulation is necessary. If the EPA concludes that 

even a small sub-population is affected by perchlorate, then the EPA is saying, in their opinion, it is 

okay to have polluted drinking water as long as it only hurts a few. I believe this is bad policy and 

hope that you would agree. Second, Drinking water is an extremely valuable resource, and will 

become more valuable in the coming decades. Water tables all over the world are falling, climate 

change is causing drastic changes to our sources of drinking water, and skyrocketing world 

population is going to make drinking water more and more of a scare resource in the decades to 

come. It is imperative that we protect our drinking water against all possible contaminates. 

Thank you for you time and attention to this issue. 

Aaron smith aaronsmith@alumni.utexas.net 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1351 

EPA Comment ID: 20388 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 733 of 1099

 

Comment: Please do not let perchlorate into our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Marilyn Alvey 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1352 

EPA Comment ID: 20389 

EPA Comment Code: 6120 

 

Comment: To Whom it may concern, Please strengthen standards for our drinking water. Why 

would anyone in their right mind allow toxic substances to be in water that US citizens are relying 

on to be safe and pure. We are the only civilized country that even puts chlorine in our drinking 

water, which is suspected of causing health problems, and is being looked at as a major player in the 

increase of breast cancer. We are so behind other nations in taking a proactive stance against toxins 

in our food, water and consumer goods. When are we going to wake up? Canada has just banned 

bisphenol A,as have most civilized countries, yet our government is still telling us that it is safeNOT! It is in liners of all canned goods, so how does one avoid it? We all can't grow and can our 

own food, we rely on the government to set safety standards and my government is sadly behind the 

curve. Please do not allow perchlorate in our drinking water. Sincerely, Marilyn Alvey 

Response: See response to comment code 6120. 

Commenter Name: Marni Hall 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1353 

EPA Comment ID: 20390 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse it's preliminary 

determination on setting a regulation for perchlorate in drinking water. It is irresponsible to ignore 

the fact that perchlorate has health impacts and if it is in our drinking water we are all at risk and 

suffer the impacts to our health. Please embrace this opportunity to protect public health. Sincerely, 

Marni Hall 

Response: See response to comment code 6120. 

Commenter Name: S. M. Gagnon 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1354 

EPA Comment ID: 20391 

EPA Comment Code: 6120 

 

Comment: I am very unhappy with the EPA's preliminary decision not to regulate perchlorate in 

drinking water. The EPA must reverse this finding and regulate perchlorate in drinking water so as 

to protect the smallest, most vulnerable members of our society -- our babies and children. Clean, 

safe drinking water should be the right of every American. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 734 of 1099

Response: See response to comment code 6120. 

Commenter Name: Francoise LaMonica 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1356 

EPA Comment ID: 20392 

EPA Comment Code: 6120 

 

Comment: The health effects from ingesting low dosage perchlorate-contaminated water are not 

well known. But it's already known that it interferes with the body's iodine intake, causing an 

inhibition of human thyroid production. Regulation of this contaminent is clearly within the mission 

and mandate of your agency to protect humal health. 

Further, since ammonium perchlorate which is used in solid rocket engine fuels has a limited shelf 

life and must periodically be replaced, a safe method of disposing of the chemical has to be designed 

and implemented. We cannot allow the buildup of perchlorate, notably in the Colorado Bassin, to 

continue unabated. 

I urge you to reconsider your agency decision not to regulate this chemical. 

Sincerely, 

Francoise LaMonica 944 Centre Street Newton, MA 02459 

Response: Please see the response to comment code 6120. Regarding commenter’s statement 

“...since ammonium perchlorate which is used in solid rocket engine fuels has a limited shelf life 

and must periodically be replaced, a safe method of disposing of the chemical has to be designed 

and implemented”, proper disposal of ammonium perchlorate falls outside of the scope of this 

regulatory action, as the Safe Drinking Water Act’s authority is focused on whether or not the 

contaminant can be in public water systems. 

Commenter Name: T. Greenlee 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1357 

EPA Comment ID: 20393 

EPA Comment Code: 6120 

 

Comment: I am appalled at the idea of drinking a rocket fuel additive. I implore you regulate 

Perchlorate strictly. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1365 

EPA Comment ID: 20394 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 735 of 1099

 

Comment: Please protect our water from being contaminted by preventing perchlorate to be in our 

water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1368 

EPA Comment ID: 20395 

EPA Comment Code: 6120 

 

Comment: Are you retarded? 

Anything and everything that is man made should be monitored, even it if is not adherently bad for 

people or the environment. 

Please reconsider or the consequences will be dire. 

Sincerely, 

A concerned citizen 

Response: See response to comment code 6120. 

Commenter Name: Shannon No surname provided 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1371 

EPA Comment ID: 20396 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. I personally do not want 

myself or my children to drink water that has a known contaminant that can effect thyroid function. 

I am actually not even sure why we would need to urge your decision in this direction as any 

chemical in our water system is alarming and should be regulated. 

Thank you for your consideration. 

Sincerely, Shannon 

Response: See response to comment code 6120. 

Commenter Name: Maureen Crossey 

Commenter Organization: Packard Manse, Inc. 

EPA Document ID: EPA-HQ-OW-2008-0692-1372 

EPA Comment ID: 20397 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 736 of 1099

 

Comment: Regulate Perchlorate. We need to convince Americans to trust their water supply. Stop 

using bottled water and filling the land with plastic waste. Maureen 

Response: See response to comment code 6120. Regarding commenter’s statement about bottled 

water, the EPA does not have the authority to regulate bottled water and this statement is outside 

the scope of this regulatory action. 

Commenter Name: J. Hammond 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1374 

EPA Comment ID: 20398 

EPA Comment Code: 6120 

 

Comment: Please keep our drinking water safe -- the EPA needs to regulate perchlorate. 

Response: Please see the umbrella response under 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1388 

EPA Comment ID: 20399 

EPA Comment Code: 6120 

 

Comment: PLEASE NO ROCKET FUEL IN OUR DRINKING WATER. 

I'M AN AMERICAN CONSUMER AND VERY CONCERNED ABOUT OUR DRINKING 

WATER AND ITS CONTAMINANTS. IT'S NO WONDER ALL OF US ARE PUTTING IN 

WATER PURIFIERS. 

PLEASE PROTECT OUR WATER AND ELIMINATE ALL POISONS SO WE CAN DRINK 

PURE WATER. 

Response: Please see the umbrella response under 6120. 

Commenter Name: Julia Earl 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1389 

EPA Comment ID: 20400 

EPA Comment Code: 6120 

 

Comment: As a children's environmental health advocate, I urge the EPA to keep perchlorate out 

of US drinking water supplies. This harmful chemical has no place in drinking water supplies. 

Special populations including pregnant women, infants, children and those of child-bearing age are 

particularly vulnerable. Therefore, I urge the U.S. Environmental Protection Agency to reverse its 

preliminary determination on setting a regulation for perchlorate in drinking water. 

Thank You, Julia Earl, MS 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 737 of 1099

Response: See response to comment code 6120. 

Commenter Name: Alisa Novelli 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1392 

EPA Comment ID: 20401 

EPA Comment Code: 6120 

 

Comment: Please do not allow any amount of perchlorate in our drinking water It is a harmful 

chemical that can impair the thyroid gland which controls growth, development and metabolism. 

Thank you, Alisa Novelli 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1397 

EPA Comment ID: 20402 

EPA Comment Code: 6120 

 

Comment: NO Perchlorate in our drinking water!!! 

Response: See response to comment code 6120. 

Commenter Name: E. Granata 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1398 

EPA Comment ID: 20403 

EPA Comment Code: 6120 

 

Comment: I urge you to reconsider your preliminary decision not to regulate the presence of 

perchlorate in drinking water. This is a public health hazard that can be remedied easily with 

standards set by EPA. 

Response: See response to comment code 6120. 

Commenter Name: L. Haas 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1399 

EPA Comment ID: 20404 

EPA Comment Code: 6120 

 

Comment: Please reverse your decision regarding the regulation of perchlorate. It is the EPA's 

responsibility to regulate any and all substances in drinking water. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 738 of 1099

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1401 

EPA Comment ID: 20405 

EPA Comment Code: 6120 

 

Comment: please do not allow rocket fuels in our drinking water 

Response: See response to comment code 6120. 

Commenter Name: P. Leitzel 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1403 

EPA Comment ID: 20406 

EPA Comment Code: 6120 

 

Comment: I have been informed that perchlorate is in rocket fuel and may soon be in our drinking 

water. What is with the EPA? You're here to protect the public, not poison us. Please do not 

deregulate the use of this substance. Thank you 

Response: See response to comment code 6120. 

Commenter Name: J. and M. V. Shaw Kline 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1406 

EPA Comment ID: 20407 

EPA Comment Code: 6120 

 

Comment: Please reverse your decision not to regulate perchlorate in our drinking water. We are 

very short sighted when we do not protect our drinking water. 

My vote is to regulate perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Mary Mintz 

Commenter Organization: Northeast Organic Farming Association (NOFA) 

EPA Document ID: EPA-HQ-OW-2008-0692-1407 

EPA Comment ID: 20408 

EPA Comment Code: 6120 

 

Comment: It is obvious that we need to monitor as many pollutants as possible in our water supply 

for our health....need we say more? 

Response: See response to comment code 6120. 

Commenter Name: Mary Mintz 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 739 of 1099

Commenter Organization: Northeast Organic Farming Association (NOFA) 

EPA Document ID: EPA-HQ-OW-2008-0692-1408 

EPA Comment ID: 20409 

EPA Comment Code: 6120 

 

Comment: Please consider reversing your decision to regulate perchlorate.....isn't this very toxic? 

Think future. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1410 

EPA Comment ID: 20410 

EPA Comment Code: 6120 

 

Comment: Please reverse you decision on not regulating percholate in our water supply. There are 

so many destructive chemicals in our water now it is freightening. There is no reason to allow this 

harmful contaminate into the water supply. Allowing this chemical in our water supply will affect the 

health and safety of everyone. Please do the right thing for all of us. Regulate the admission of 

percholate now. 

Response: See response to comment code 6120. 

Commenter Name: Heather Morgan 

Commenter Organization: Morgan Holistic Health 

EPA Document ID: EPA-HQ-OW-2008-0692-1411 

EPA Comment ID: 20411 

EPA Comment Code: 6120 

 

Comment: We,as health professionals, believe that Perchlorate needs to be removed completely 

from drinking water and water should be constantly monitored to insure no levels of this toxic 

chemical are detected. There is a health crisis in America, and part of this is due to environmental 

toxic exposure and we need to take action NOW to reverse the levels of exposure that are compiling 

from all forms of exposure which cause diseases in our bodies. Clean water, free of chemicals, is the 

most important thing we can do for our health. 

Response: See response to comment code 6120. 

Commenter Name: L. Huggins 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1416 

EPA Comment ID: 20412 

EPA Comment Code: 6120 

 

Comment: Please, reconsider your decision, you MUST regulate perchlorate in drinking water as 

safety of population is extremely important for the future of the country and its resources. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 740 of 1099

Response: See response to comment code 6120. 

Commenter Name: S. Kagen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1417 

EPA Comment ID: 20414 

EPA Comment Code: 6120 

 

Comment: I protest this lackadaisical response to poison in our drinking water. 

Here's an idea. Put a few drops of perchlorate into everything you drink, and everything you boil, 

like potatoes or broccoli. Wait two years and then get back to me on how your health is doing. 

This will be overtuned in a heartbeat in a couple of months. 

Do the right thing. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1420 

EPA Comment ID: 20415 

EPA Comment Code: 6120 

 

Comment: Please regulate perchlorate so it cannot be added to our drinking water. 

Response: Perchlorate is not added to drinking water. EPA has determined to regulate perchlorate, 

See response to comment code 6120. 

Commenter Name: Melanie A. Marty, Ph.D. 

Commenter Organization: Children's Health Protection Advisory Committee 

EPA Document ID: EPA-HQ-OW-2008-0692-0962 

EPA Comment ID: 20416 

EPA Comment Code: 6120 

 

Comment: November 3,2008 Stephen L. Johnson, Administrator United States Environmental 

Protection Agency 1200 Pennsylvania Avenue, N.W. Washington, D.C.. 20460 RE: Preliminary 

Regulatory Determination on Perchlorate; Docket ID No. EPA-HQ- OW-2008-0068 

Dear Administrator Johnson: 

The Children's Health Protection Advisory Committee (CHPAC) has been closely monitoring the 

Agency's approach towards perchlorate as a drinking water contaminant. Our March 2006 letter to 

you recommended that the Agency develop a federal Maximum Contaminant Level (MCL) for 

perchlorate. This recommendation was based upon the ability of perchlorate to disrupt thyroid 

hormone synthesis, lowering circulating levels of thyroid hormone, and the critical importance of 

thyroid hormone to brain development. Our concern over perchlorate has focused on in utero and 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 741 of 1099

postnatal development, particularly for neonates whose exposures can be considerably greater than 

adults, and who lack stores of thyroid hormone. The life-long consequences of impaired brain 

development are sufficient to merit setting a protective MCL for perchlorate. Further, setting an 

MCL would mandate testing of public water supplies, and allow discovery of hot spots of 

contamination. 

We are writing to you again on perchlorate because in the Preliminary Regulatory Determination on 

Perchlorate dated Oct 10, 2008, EPA decided against setting an MCL. This decision was based upon 

the establishment of a flawed benchmark, a Health Risk Limit (HRL) of 15 ug/L. This benchmark is 

clearly too high for infants as the Agency's own calculations show that an HRL of 15 ug/L would 

allow daily exposures to infants that are 2-5 times higher than the Reference Dose (RfD) (Federal 

Register, Vol 73, No.198, October 10, 2008, 60262-60282). The RfD is meant to be applied to 

everyone, yet in the case of perchlorate it is applied to adults but not infants. This decision does not 

recognize the science which supports the exquisite sensitivity of the developing brain to even small 

drops in thyroid hormone levels and the fact that neonates have much diminished stores of thyroid 

hormone relative to adults. The Agency must ensure that this life stage is adequately protected. 

Response: See response to comment code 6120. 

Commenter Name: Melanie A. Marty, Ph.D. 

Commenter Organization: Children's Health Protection Advisory Committee 

EPA Document ID: EPA-HQ-OW-2008-0692-0962 

EPA Comment ID: 20424 

EPA Comment Code: 6120 

 

Comment: In summary, the CHPAC believes that all three conditions for setting an MCL are met 

and that the Agency must set an MCL for perchlorate. We request further communication with you 

and your staff regarding the Preliminary Regulatory Determination on Perchlorate. This is a critical 

and timely issue given the concerns over endocrine disruption by thyroid-active agents of various 

types and their potential to interact with other neurotoxicants to impair early life brain development. 

While many of these other neurotoxicants (heavy metals, pesticides, PCBs) have been aggressively 

targeted by USEPA, the lack of regulation of perchlorate is an obvious oversight that can readily be 

addressed. Thank you for your attention to this matter. 

Sincerely, Melanie A. Marty, Ph.D., Chair Children's Health Protection Advisory Committee 

Cc: Benjamin Grumbles, Assistant Administartor, OW Cynthia Dougherty, Director, OGWDW 

Eric Burneson, Chief, Targeting and Analysis Branch, OGWDW 

References: 

Blount BC, Pirkle IL, Osterlob JD, Valentin-Blasini L, Caldwell K.L. 2006. Urinary perchlorate and 

thyroid hormone levels in adolescent and adult men and women living in the United States. Environ 

Health Perspect 114:1865-1871. 

Greer MA, Goodman G, Piens RC, Greer SE (2002) Health effects assessment for environmental 

perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake in 

humans. Environ Health Perspect 110:927-937. 
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MADEP, 2006 Perchlorate Monitoring Results - Confirmed Above 1.0 ppb (Available at 

http://www.mass.govidep/water/drinlcing/percinfo.htm) 

Response: See response to comment code 6120. 

Commenter Name: Wenonah Hauter 

Commenter Organization: Food & Water Watch 

EPA Document ID: EPA-HQ-OW-2008-0692-1259 

EPA Comment ID: 20425 

EPA Comment Code: 6120 

 

Comment: November 7, 2008 

Water Docket Environmental Protection Agency 1200 Pennsylvania Ave., NW Washington, DC 

20460 

RE: Docket ID No. EPA-HQ-OW-2008-0692 

Food & Water Watch, a Washington DC-based consumer advocacy organization, opposes the 

Environmental Protection Agency’s Preliminary Regulatory Determination on Perchlorate. 

Food & Water Watch hopes that the EPA will reconsider this preliminary determination and will 

issue a national primary drinking water regulation for perchlorate in accordance with the Safe 

Drinking Water Act. 

Perchlorate has been found in the drinking water supply of 35 states and the District of Columbia. 

Widespread human exposure to perchlorate was confirmed by the Centers for Disease Control’s 

NHANES study, which found that 100 percent of the 2,820 randomly selected study participants 

had detectable levels or perchlorate in their urine.[FNi: Blount, Benjamin C et al. "Perchlorate 

Exposure of the US Population, 2001-2002." Journal of Exposure Science and Environmental 

Epidemiology. 17: 400-407, 2007.] 

The widespread exposure of the population to some level of perchlorate raises serious health 

concerns. Perchlorate can inhibit the thyroid gland’s iodine uptake, potentially leading to 

hypothyroidism. Severe hypothyroidism during pregnancy can lead to abnormal fetal cognitive 

development, and even mild hypothyroidism during pregnancy is associated with subtle cognitive 

defects in children. Thus, perchlorate could alter fetal brain development, having lifelong cognitive 

effects for those affected. 

The EPA’s failure to regulate perchlorate in drinking water act places consumers - especially 

pregnant woman and children - at risk. 

In response to this misguided determination, the EPA’s own Children’s Health Protection Advisory 

Committee has drafted a letter expressing its concern with the EPA’s decision not to regulate 

perchlorate. Members of the committee claim that EPA rushed a decision on perchlorate without 

taking time to review all the latest peer-reviewed studies. 
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Given the vital importance of fetal central nervous development not only for long-term health and 

development of children, but also for the viability of fetuses, why would the EPA rush to a decision? 

Unfortunately the only conclusion we can draw is that the EPA has issued this determination to 

avoid strapping the Department of Defense with costs to clean-up near military bases, missile testing 

sites and chemical plants. While millions of consumers’ health is jeopardized, it seems the budget 

concerns of the Pentagon or White House are driving EPA’s decision. 

This determination is clearly another instance of a regulatory agency shrinking from its responsibility 

to protect the American public. Instead of fulfilling your obligations under the SDWA, the EPA has 

once again folded to pressure. 

Sincerely, 

Wenonah Hauter Executive Director 

Response: Please see response to comment code 6120. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection 

EPA Document ID: EPA-HQ-OW-2008-0692-1422 

EPA Comment ID: 20430 

EPA Comment Code: 6120 

 

Comment: November 6, 2008 

Water Docket U.S. Environmental Protection Agency Mailcode 2822T 1200 Pennsylvania Avenue, 

NW Washington, D.C. 20460 

Docket ID No. EPA-HQ-OW-2008-0692. Drinking Water: Preliminary Regulatory Determination 

on Perchlorate 

The Massachusetts Department of Environmental Protection (MassDEP) is submitting the 

following comments in response to the United States Environmental Protection Agency’s (EPA’s) 

request for comment on its preliminary determination not to regulate perchlorate in drinking water 

at a national level, Docket ID No. EPA- HQ-OW-2008-0692 entitled "Drinking Water: Preliminary 

Regulatory Determination on Perchlorate". These comments were prepared by scientists in the 

MassDEP Office of Research and Standards (ORS) including Carol Rowan West, MPH, Director, 

ORS; Tsedash Zewdie Ph.D., Senior Toxicologist, ORS; and C. Mark Smith Ph.D., S.M., Deputy 

Director, ORS. 

1. A Health Protective National Standard is Needed. MassDEP disagrees with EPA’s draft decision 

not to regulate perchlorate at the national level and believes that a health protective national drinking 

water standard for perchlorate is both warranted and necessary to protect the health of our nation’s 

children. Overall, EPA’s assessment does not adequately support its determination to not regulate 

perchlorate for a sizeable number of United State’ citizens, by disregarding elevated exposures and 

potential developmental effects in the neonate. This decision is inconsistent with basic precepts of 

public health protection. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Response: See response to comment code 6120. 

Commenter Name: Carol Rowan West 

Commenter Organization: Massachusetts Department of Environmental Protection 

EPA Document ID: EPA-HQ-OW-2008-0692-1422 

EPA Comment ID: 20436 

EPA Comment Code: 6120 

 

Comment: In conclusion, EPA’s determination that a national drinking water is not warranted is 

based on an incomplete assessment of the data and will place many of the nation’s most vulnerable 

citizens, our newborn children and fetuses at an early stage of development, at risk. MassDEP 

believes that there is compelling evidence to support a national drinking water standard for 

perchlorate at a value well below EPA’s HRL of 15 ppb. 

For further information please contact Carol Rowan West at 617-292-5510 

(Carol.RowanWest@state.ma.us) or C. Mark Smith at 617-292-5509 (C.Mark.Smith@state.ma.us). 

References 

Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell KL (2006). Urinary perchlorate and 

thyroid hormone levels in adolescent and adult men and women living in the United States. Environ 

Health Perspect 114:1865-1871. 

Burgi H, Benguerel M, Knopp J, Kholer H, and Studer H (1974). Influence of perchlorate on 

secretion of non-thyroxin iodine by the normal human thyroid gland . Europ J Clin Invest 4:65-69. 

CA EPA (2004). Public Health Goal for Perchlorate in Drinking Water. Pesticide and 

Environmental Health Hazard Assessment. California Environmental Protection Agency. 

Dasgupta PK, Kirk AB, Dyke JV, and Ohira S-I (2008). Intake of iodine and perchlorate and 

excretion in human milk. Environ Sci Technol 14:815-8121. 

Ginsberg GL, Hattis DB, Zoeller RT, Rice DC (2007). Evaluation of the U.S. EPA/OSWER 

preliminary remediation goal for perchlorate in groundwater: focus on exposure to nursing infants. 

Environ Health Perspect 115:361-369. 

Ginsberg GL, Rice DC (2005). The NAS perchlorate review: questions about the perchlorate RfD. 

Environ Health Perspect 113:1117-1119. 

Greer MA, Grim Y, Inoue K (1969). Fate of iodide derived from intrathyroidal hydrolysis hydrolysis 

f thyroglobulin. Endocrinology 85:837-845. 

Isaacs GH, Athans, JC, Rosenberg IN (1966). Effects of thyrotropin upon thyroidal iodide. Studies 

using thyroid venous cannulation and two radioiodine isotops. J Clin Invest 45:758 

NRC (2005). Health Implications of Perchlorate Ingestion. In. Washington D.C.: National 

Academies Press. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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MassDEP (2006). Update to Perchlorate Toxicological Profile and Health Assessment. 

Massachusetts Department of Environmental Protection, Office of Research and Standards. 

Pearce EN, Leung AM, Blount BC, Bazrafshan HR, He X, Pino S, Valentin-Blasini L, Braverman 

LE (2007). Breast milk iodine and perchlorate concentrations in lactating Boston-area women. J Clin 

Endocrinol Metab 92:1673-1677. 

Rosenberg IN, Athans JC, Behar A (1961). Thyrotropin induced release of iodide from the thyroid. 

Endcrinology 69:438-455. 

Sinha RA, Pathak A, Mohan V, Bandyopadhyay S, Rastogi L, Godbole MM (2008). Maternal thyroid 

ormone: a strong repressor of neuronal nitric oxide synthase in rat embryonic neocortex. 

Endocrinology 149:4396-4401. 

Steinmaus C, Miller MD, Howd R (2007). Impact of smoking and thiocyanate on perchlorate and 

thyroid hormone associations in the 2001-2002 national health and nutrition examination survey. 

Environ Health Perspect 115:1333-1338. 

Tellez R, Michaud Chacon P, Reyes Abarca C, Blount BC, Van Landingham CB, Crump KS, Gibbs 

JP (2005). Long-term environmental exposure to perchlorate through drinking water and thyroid 

function during pregnancy and the neonatal period. Thyroid 15:963-975. 

US EPA (2002). Perchlorate Environmental Contamination: Toxicological Review and Risk 

Characterization. United States Environmental Protection Agency, Office of Research and 

Development, NCEA-1-0503, External Review Draft. 

Wolff, J. (1988). Perchlorate and thyroid gland. Pharmacol Rev 50: 89-106. 

Zoeller RT (2006). Collision of basic and applied approaches to risk assessment of thyroid toxicants. 

Ann N Y Acad Sci 1076:168-190. 

Zoeller RT, Rice DC (2004). Critical effect of perchlorate on neonates is iodide l Pharmacol 40:376-

377; author reply 378-379. 

Response: See response to comment code 6120. 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Dept. of Environmental Protection 

EPA Document ID: EPA-HQ-OW-2008-0692-1526 

EPA Comment ID: 20447 

EPA Comment Code: 6120 

 

Comment: November 10, 2008 

Water Docket Environmental Protection Agency Mail Code: 2822T 1200 Pennsylvania Ave, NW 

Washington, DC 20460 RE: Docket ID No. EPA-HQ-OW-2008-0068 

To Whom It May Concern: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Thank you for the opportunity to provide comments on the Preliminary Regulatory Determination 

on Perchlorate in Drinking Water proposed by USEPA, which was published in the Federal Register 

of October 10, 2008 (73 Fed. Reg. 60262-82 (October 10, 2008)). On October 7, 2005 the New 

Jersey Department of Environmental Protection ( NJDEP) received from the New Jersey Drinking 

Water Quality Institute (NJDWQI), a legislatively created public advisory body, a recommendation 

to establish an MCL for perchlorate of 5 ug/L. The Department plans to propose such an MCL 

including monitoring and compliance determination requirements before the end of 2008 with 

adoption later in 2009. The NJDEP believes that having an MCL for perchlorate is good public 

health policy for both New Jersey and for the country as a whole. 

There are two aspects of the proposal on which we would like to 

Comment: 1) the proposal of a health reference level (hrl) for perchlorate of 15 ug/l. It is our 

understanding that an hrl is a drinking water concentration intended to protect individuals, including 

sensitive subgroups, from adverse effects resulting from a lifetime of exposure, similar to a lifetime 

health advisory or a maximum contaminant level goal. 2) The decision not to develop a regulatory 

standard (mcl) for perchlorate, and to develop guidance (a health advisory) instead, based on 

population exposed above the hrl. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Dept. of Environmental Protection 

EPA Document ID: EPA-HQ-OW-2008-0692-1526 

EPA Comment ID: 20452 

EPA Comment Code: 6120 

 

Comment: Based on the above comments, we strongly urge USEPA to reconsider its conclusion 

that 15 ug/L is a health protective concentration for perchlorate in drinking water. We also strongly 

urge USEPA to reconsider its determination to not regulate perchlorate. The New Jersey Drinking 

Water Quality Institute recommendations regarding perchlorate can be found at 

http://www.nj.gov/dep/watersupply/perchlorate_mcl_10_7_05.pdf. For further information or 

clarification about our position, contact Dr. Eileen Murphy at 609-984-6070, or 

Eileen.murphy@dep.state.nj.us . 

Sincerely, 

Jeanne Herb, Director, Office of Policy and Planning 

C: Michele Putnam, NJDEP Eileen Murphy, NJDEP Barker Hamill, NJDEP Sandra Krietzman, 

NJDEP Betty Boros-Russo, NJDEP Gloria Post, NJDEP Perry Cohn, NJDHHS Mark Robson, 

Chair, New Jersey Drinking Water Quality Institute 

Citations 

Brown, R.S., Huang, S.A. and Fisher, D.S. (2004). The maturation of thyroid function in the 

perinatal period and during childhood. In: The Thyroid. A Fundamental and Clinical Text. 9th 

Edition. Braverman, L.E. and Utiger, R.D., eds., Lippincott Williams & Wilkins, Philadelphia. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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NRC (2005). Health Implications of Perchlorate Ingestion. National Research Council Board on 

Environmental Studies and Toxicology. The National Academies Press, Washington, D. C. 

www.nap.edu 

Van den Hove, M.F., et al. (1999). Hormone synthesis and storage in the thyroid of human preterm 

and term newborns: effect of thyroxine treatment. Biochimie 81:563-570. 

Zoeller, R.T. and Rice, D.C. (2004). Critical effect of perchlorate on neonates is iodide uptake 

inhibition (Letter to the editor). Regulatory Toxicology and Pharmacology, 40(3): 376-377. 

Response: EPA has determined to regulate, See response to comment code 6120. Once the 

National Primary Drinking Water Regulation is final, EPA will consider revisions to the health 

advisory. 

Commenter Name: Gregg Grunenfelder 

Commenter Organization: Washington State Department of Health; and Oregon Department of 

Human Services 

EPA Document ID: EPA-HQ-OW-2008-0692-1529 

EPA Comment ID: 20453 

EPA Comment Code: 6120 

 

Comment: November 10, 2008 

Docket ID No. EPA-HQ-OW-2008-0692 

Water Docket Environmental Protection Agency Mailcode: 2822T 1200 Pennsylvania Avenue, 

Northwest Washington, DC 20460 

To Whom It May Concern: 

Recently, the US Environmental Protection Agency (EPA) solicited comments for an action notice 

placed on the Federal Register relating to a preliminary regulatory determination for perchlorate in 

drinking water. The agency stated that levels of perchlorate found in drinking water systems were 

not at levels of concern and that there was no meaningful opportunity for health risk reduction 

through a national drinking water regulation. The Washington State Department of Health and the 

Oregon Department of Human Services disagree with EPA’s conclusion and recommend that EPA 

reconsider the need for a national drinking water standard for perchlorate. 

Extensive use and improper disposal of this highly water-soluble compound has led to groundwater 

contamination throughout the United States. To date, the extent of groundwater contamination has 

not been well characterized. It is known, however, that here in the northwest low levels of 

perchlorate have been found in groundwater in some tested areas of eastern Washington and 

Oregon. 

Response: See response to comment code 6120. Regarding commenter’s statement “...Extensive 

use and improper disposal of this highly water-soluble compound has led to groundwater 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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contamination throughout the United States”, proper disposal of perchlorate is required by EPA’s 

RCRA regulations and this subject matter falls outside of the scope of this regulatory action. 

Commenter Name: James Barton 

Commenter Organization: Underwater Ordnance Recovery 

EPA Document ID: EPA-HQ-OW-2008-0692-1531 

EPA Comment ID: 20460 

EPA Comment Code: 6120 

 

Comment: Opposition to EPA's Decision to Not Regulate Perchlorate - A Threat to the Great 

Lakes 

James Barton, President - Underwater Ordnance Recovery jamesbarton@uwuxo.com Steve Pollack 

ESQ, - Director Blue Eco Legal Council steve@ecoesq.com 

Removal of an estimated one million tons of unexploded ordnance and bulk containers abandoned 

on the floor of the Great Lakes is unlikely if the US EPA decision to deregulate perchlorates stands. 

Perchlorates are the most persistent munitions constituent leaching from decaying military 

explosives abandoned in a marine environment. Already beginning to show up at certain lakefront 

municipal water treatment facilities on both the US and Canadian sides, deregulation of perchlorates 

threatens the essential rational for removal of these "point source" emitters of perchlorates, and sets 

the stage for irreversible and unnecessary perchlorate contamination of the Great Lakes. 

Rocket fuel is commonly provided as the most likely source for perchlorate contaminated drinking 

water. While perchlorates are used for that purpose, they are also a major component of 

conventional military explosives. Prior to WWII, Germany manufactured an entire class of civilian 

explosives based solely on perchlorates, and throughout WWII Russia manufactured numerous 

types of explosive filled projectiles containing up to 89% perchlorates by volume. The percent by 

volume of perchlorates used in period manufacture of US military explosives vary but 25% is a 

conservative number overall. 

Unaware of the impending threat to the United States and Canadaâ€TMs shared strategic asset 

known as the Great Lakes, the US Environmental Protection Agency is said to have bowed to 

pressure from the Pentagon, according to US Senate Environmental Committee Chair, Senator 

Barbara Boxer (D-CA), adding; "To see the Bush EPA just walk away is shocking". Paul Yaroschak, 

Pentagon Deputy Director for Emerging Contaminants denies this, saying; "We have not intervened 

in any way", adding "The EPA decision was based on the Safe Drinking Water Act". 

The EPA has identified over 400 land based active or formerly used defense sites across 35 states 

where perchlorates have already been detected at dangerous levels in local aquifers, affecting an 

untold number of adjacent communities. Most of these sites have had little exposure to rocket fuel, 

but do have a documented history of military high explosive use or manufacture. Soils contaminated 

with decadeâ€TMs worth of perchlorate laden high explosive residues have become "non- point" 

sources of pollution, and are as difficult and costly to remediate as the aquifers they continue to 

pollute every time it rains. By contrast, unexploded munitions and other defense wastes intentionally 

dumped and abandoned on the floor of the Great Lakes remain largely intact due to cold fresh 

waters, and fit the classic description of "point source" emitters of pollutants that can and must be 

eliminated. 
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The most common critical pathway for perchlorate to enter the human body is through 

contaminated drinking water. It primarily attacks the thyroid gland where it slows metabolic rate, 

which is why it was once used to fatten livestock and poultry before being linked to breast and 

testicular cancer. The thyroid glands of children are most susceptible to perchlorates, which can also 

be transferred to the fetus maternally. Women are said to be ten times more susceptible to 

perchlorate uptake than men. 

The incredible persistence of perchlorate gives it the ability to migrate far from its point of origin, 

including into crops. Because of this persistence, the technical and economic challenges involved in 

attempting to eliminate perchlorate once it has entered an ecosystem illustrate that removal of point 

sources is the most economical course of action. Much of southern California for instance, is already 

forced to use perchlorate laced waters from the Colorado River, contaminated from a single DoD 

managed perchlorate manufacturing facility that used unlined retention ponds and operated in the 

middle of the Nevada desert; miles away from the Colorado River. 

Some might be surprised to learn the scope of the problem in the Great Lakes, and canâ€TMt 

imagine how or why it happened. The question is what we are going to do about it. Ask a Great 

Lakes resident and the answer is a foregone conclusion; pull the munitions and related defense 

wastes out of the Lakes before itâ€TMs too late. While few are aware that high explosive filled 

munitions provide a substantial source of perchlorates, large numbers of munitions found elsewhere 

in a more advanced state of decay have been linked to a decline in fisheries. Where others were 

helpless to address such problems due to a lack of removal technology, we are not; but in fact are on 

the verge of choosing a similar fate. 

The prime directive of the US Department of Defense is defending this nation against international 

strategic threats, and the projection of US influence and power; not long term domestic 

environmental threats, especially the ones they had a hand in creating. Allowing any waste originator 

into the decision making process regarding toxic waste clean up is a foolâ€TMs game; and the 

DoDâ€TMs dismal track record pertaining to underwater unexploded ordnance clean up bears this 

out. Where considerable resources are being devoted to protect the health and economic viability of 

individual communities from land based defense wastes that you can see; the health and economic 

viability of a nation is being neglected for what you canâ€TMt. 

Ask a US defense official what we are going to do about the defense wastes in the Great Lakes, and 

if you can get past the debate on whether the threat justifies remedial action, he will ask you who is 

going to pay for the clean up. At the upper levels in the Pentagon itâ€TMs all about the money, and 

how long you can delay spending a dime on anything other than your prime directive. While that 

approach has worked well for them in the past, time is running out for the rest of us. 

Deregulating perchlorate will not make it go away nor mitigate its harmful effects; using the Safe 

Drinking Water Act to justify it is an affront to our national identity; and its impact on the Great 

Lakes is a threat to our national security. 

This action is clearly not the will of the men and women who proudly serve the US EPA, and does a 

disservice to the citizens whose interests they represent. Therefore, the decision to deregulate 

perchlorates must be delayed until after responsible leadership returns to the White House. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 750 of 1099

James Barton is an international expert on underwater ordnance, and regarded by some as the 

worlds leading expert on the subject. 

Steve Pollack is the Director of Blue Eco Legal Council, specializing in environmental pollution at 

federal facilities. 

Response: See response to comment code 6120. EPA acknowledges commenter’s concern about 

the clean up of perchlorates in areas that serve as point source contamination to water, including 

The Great Lakes. The clean up of perchlorate contamination in the United States is related to EPA’s 

CERCLA regulations and this subject matter falls outside of the scope of this regulatory action. 

Commenter Name: J. Green 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0148 

EPA Comment ID: 20461 

EPA Comment Code: 6120 

 

Comment: This is a Public Comment Regarding EPA’s refusal to regulate Perchlorate under the 

Safe Water Drinking Act (Docket ID EPA-HQ-OW-2008-0692): 

Perchlorate is a chemical in rocket fuel that has been linked to thyroid problems in pregnant women, 

newborns and young children. Not regulating this harmful chemical in our drinking water is 

unacceptable. 

Perchlorate is found in drinking water in 35 states, and according to the EPA’s own data, 16 million 

Americans are at risk of being exposed to this dangerous chemical. 

Response: See response to comment code 6120. 

Commenter Name: J. Green 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0148 

EPA Comment ID: 20463 

EPA Comment Code: 6120 

 

Comment: Native Americans and Hispanics are especially vulnerable in New Mexico, as we have so 

many military weapons production facilities here. Perchlorates way beyond allowable parts per 

billion have been found in groundwater and streams. It is unacceptable to sacrifice the health of 

people and the environment for the sake of military-industrial profit. The EPA is our only recourse 

for protection from being poisoned to death by our own government. Please do your job EPA and 

enforce our clean water laws. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Vicky and Bll Clary 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0622 

EPA Comment ID: 20464 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 751 of 1099

EPA Comment Code: 6120 

 

Comment: Docket Identification (ID) Number: EPA-HQ-OW-2008-0692 Preliminary Regulatory 

Determination on Perchlorate Re: Request for extension of comment period 

I am writing to express my concern regarding the EPA's failure to regulate perchlorate, as well as the 

proposed reference level, which fails to protect - and will adversely affect -- the health and 

development of hundreds of thousands, perhaps millions of American children. 

If the dangers we even only restricted to 17 million people alone that would be enough to take a 

more serious look at regulating, but the numbers of people affected is more like 20 to 40 MILLION 

+ ! Already synthyroid is the number two prescribed medication in the country. This a drain on the 

insurance companies not to mention the devistation thyroid desease causes the patient. This 

chemical has been shown to cause thyroid problems. As a thyroid patient I can tell you every day is a 

struggle to keep control of my symptoms and I would not wish it on any one especially our children! 

Response: See response to comment code 6120. 

Commenter Name: Eric Keller 

Commenter Organization: Phi Alpha Delta, University of Detroit Mercy 

EPA Document ID: EPA-HQ-OW-2008-0692-1428 

EPA Comment ID: 20466 

EPA Comment Code: 6120 

 

Comment: The regulation of perchlorate in our nation's water ways is rationally needed. From our 

drinking water to storm drains; streams into lakes; swamps to our forests; our land to our produce; 

into our wildlife and livestock, even our families, friends, and children, this regulation is needed. Our 

constitution demands this of us, and we must not be divided in makiong this stand; for our states, 

for our nation. 

The People, their representives, the courts, the administration, they all have a ligitimate use of 

authority to provide for and protect ourselves. It would be an unjustice to the american people in 

allowing this pollutent to contaiminate our nation, in this way, and amount, any longer. Halfmeasures have to be stopped. We must take a firm stand, here and now, to show the american 

people, individuals and businesses, government and religion, neighbors and strangers, freinds and 

fowes, all over the world that the american government, its agencies, like the Environmental 

Protection Agency, are not going to stand idely by, and watch pollutants or contaiminates distroy 

our environment and severilly harm human beings and other inhabitants of this planet. We are 

reasonable,rationial, understanding, and forgiving, but we can not afford to be ignorant or blind, we 

can not afford to be walked over and abused any more, no matter in what situation, isuues, or relm. 

Please take a stand, and strictly,within reasoning and speed, regulate perchlorate, (and other 

contaiminates and/or pollutants like) it is our duty to our posterity. 

Thank you for your time, consideration, and civil service, 

Respectfully, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 752 of 1099

Eric Keller Vice President, Phi Alpha Delta University of Detroit Mercy 

kelleree@students.udmercy.edu 

Response: See response to comment code 6120. 

Commenter Name: P. Pasles 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1431 

EPA Comment ID: 20467 

EPA Comment Code: 6120 

 

Comment: I am writing to ask the EPA to reverse its preliminary decision that it will not regulate 

perchlorate in drinking water. I am the father of two small children, and I also have some 

professional training that allows me to understand the health issues (which have been established 

with the aid of statistical analysis-- I am a mathematician). Even a small amount of perchlorate can 

affect growth, and can cause other long-term health problems as well. It is prevalent in our water 

supply all over this country, and the EPA needs to show leadership on this issue so that standards 

are set at a national level. 

Response: See response to comment code 6120. 

Commenter Name: T. Novak 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1433 

EPA Comment ID: 20468 

EPA Comment Code: 6120 

 

Comment: Just DO THE RIGHT THING!!!!!! Why in the world would you ever allow ANY 

rocket fuel into our drinking supply? 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1435 

EPA Comment ID: 20469 

EPA Comment Code: 6120 

 

Comment: "I understand the dangers of perchlorate and ask you to keep the testing requirement 

intact for our public drinking water supplies. Removal of the testing requirement would eliminate 

detection of perchlorate in the case of accidental or intentional contamination of drinking water 

supplies, such as the Tewksbury Massachusetts contamination in 2004." . As a parent of 3 children, I 

feel it is vital to continue monitoring for this, and other contaminents. Thank you 

Response: This regulatory action does not affect testing requirements for perchlorate in local 

jurisdictions. See response to comment code 6120. 

Commenter Name: D. Waggoner 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 753 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1440 

EPA Comment ID: 20470 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: M. Sonnenblick 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1441 

EPA Comment ID: 20471 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Developing fetuses, infants and children with thyroid impairment may suffer mental retardation, loss 

of hearing and speech or deficits in motor skills. As a public school educator we are seeing more and 

more children with educational deficits, including learning disabilities, autism/Asperger's disorders, 

speech and language needs, and occupational therapy issues. These are expensive to remediate and 

often cause life-long struggles for the children and their families. We need to decrease the risk of 

babies developing these problems. Please regulate perchlorate and all other risky chemicals found in 

drinking water supplies. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1444 

EPA Comment ID: 20472 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

As a registered nurse and a mother, I am concerned about the effects of low levels of perchlorate 

contamination on human thyroid function, and the consequent harm to developing fetuses, infants 

and children. 

Response: See response to comment code 6120. 

Commenter Name: G. Bastien 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1446 

EPA Comment ID: 20473 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 754 of 1099

EPA Comment Code: 6120 

 

Comment: Perchlorate should not be used in drinking water because of the threat to endocrine 

system. thyroid disruption is not something to be trifled with because of it overall impact on mood, 

general health, etc.. Mammalian studies have sent out warnings to public health officials giving us a 

choice to use greater filtration in better water treatment plants while we clean up our ground and 

surface water. 

I urge the EPA director to reverse the decision to allow the use of perchlorate in our water 

treatment plants. 

Sincerely, 

Greg Bastien 2709 E. Minnehaha Parkway Minneapolis, MN 55417 

Response: See response to comment code 6120. 

Commenter Name: Tom 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1450 

EPA Comment ID: 20474 

EPA Comment Code: 6120 

 

Comment: Please regulate and limit Perchlorate emissions. 

Perchlorate has been shown to damage the thyroid at very low concentrations, which in turn can 

lead to developmental problems, particularly in children. 

Thank you. Tom 

Response: See response to comment code 6120. 

Commenter Name: M. J. Strawn 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1451 

EPA Comment ID: 20475 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. Perchlorate contamination is 

a nationwide problem which has health impacts at lower levels than previously thought. 

EPA agrees that perchlorate has been found in 395 sites in 37 states, including 153 public water 

systems serving over 20 million people -- and other estimates of human perchlorate exposure are 

higher. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 755 of 1099

Even in small amounts, perchlorate can impair the thyroid gland, which controls growth, 

development, and metabolism. Developing fetuses, infants, and children with thyroid impairment 

may suffer mental retardation, loss of hearing and/or speech, or deficits in motor skills. 

Exposure via drinking water occurs constantly, every day, for extremely long periods of time. EPA 

should not shirk its responsibilities to ensure the safety of twenty million people via this route. 

Please regulate the amount of perchlorate in drinking water. Twenty million Americans are counting 

on you. 

Response: See response to comment code 6120. 

Commenter Name: J. Hudson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1454 

EPA Comment ID: 20476 

EPA Comment Code: 6120 

 

Comment: I am concerned about the decision not to regulate perchlorate in our drinking water. 

Since this agent is so widespread in our country-found in 37 states-it seems even more critical to 

both regulate and monitor its effect on such a huge segment of the population. 

I hope the EPA will reconsider this decision for the health of all, but especially the very young and 

the unborn. 

Thank You 

Jim Hudson 

Response: See response to comment code 6120. 

Commenter Name: M. Nolasco 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1464 

EPA Comment ID: 20477 

EPA Comment Code: 6120 

 

Comment: I am writing to urge the US EPA to reverse its determination not to set a regulation for 

perchlorate in drinking water. 

The health impact of percholate contamination is a nationwide problem. 

Please keep this out of our drinking water. 

M. Nolasco 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 756 of 1099

Commenter Name: T. Bell 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1465 

EPA Comment ID: 20478 

EPA Comment Code: 6120 

 

Comment: I am very concerned that we, as a country, are not doing more to insure clean and safe 

water standards. More and more compounds in our water have been found to have adverse effects 

in extremely small amounts that are currently legal. To relax or expand allowable amounts of trace 

poisons that hurt our children and county is just not right. 

Response: See response to comment code 6120. 

Commenter Name: Leslie McCollom 

Commenter Organization: O'Hanlon, McCollom & Demerath 

EPA Document ID: EPA-HQ-OW-2008-0692-1467 

EPA Comment ID: 20479 

EPA Comment Code: 6120 

 

Comment: My name is Leslie McCollom, and I am a private individual who practises law in Austin, 

Texas, at 808 West Avenue, Austin, Texas 78701. I urge the U.S. Environmental Protection Agency 

to reverse its preliminary determination on setting a regulation for perchlorate in drinking water. The 

reasons for my objections to your agency's preliminary determination is because perchlorate 

contamination is a nationwide problem and has health impacts at lower levels than previously 

thought, according to research I have reviewed. I see no need to list all of the sources, since I am 

assuming that your agency has done its homework and reviewed all available data, research, and 

opinion on the effects of this chemical. A national primary drinking water regulation would provide 

a meaningful opportunity to protect public health. 

Perchlorate is a harmful chemical used in rocket fuel, flares, and explosives. Perchlorate, even in 

small amounts, can impair the thyroid gland, which controls growth, development and metabolism. 

Developing fetuses, infants and children with thyroid impairment may suffer mental retardation, loss 

of hearing and speech or deficits in motor skills as a result of consuming this chemical It is my 

understanding that the EPA agrees that perchlorate has been found in 395 sites in 37 states, 

including 153 public water systems serving over 20 million people. Some estimates are even higher. 

Under these circumstances, I believe the EPA has a legal duty to set a standard for this harmful 

chemical in drinking water, as well as in any and all bodies of water that are subject to regulation 

under the Clean Water Act. 

Leslie McCollom O'Hanlon, McCollom & Demerath 808 West Avenue Austin, Texas 78701 (512) 

494-9949 

Response: See response to comment code 6120. 

Commenter Name: SueAnn Hurley 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1459 

EPA Comment ID: 20480 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 757 of 1099

EPA Comment Code: 6120 

 

Comment: To Whom it may concern: I urge the EPA to reverse your recent decision not to 

regulate perchlorate in public drinking water. It is too risky and dangerous. Thank you, SueAnn 

Hurley 

Response: See response to comment code 6120. 

Commenter Name: J. Egan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1455 

EPA Comment ID: 20481 

EPA Comment Code: 6120 

 

Comment: Maintaining current standards for perchlorate content is needed to clean up existing 

ground water contamination and prevent future spills. Although the cost is significant, the 

degradation of our environment is more costly; in increased health care costs, loss of productivity, 

and land value. 

Response: This is not a comment. No response necessary. 

Commenter Name: Richard, Alison, Henry Whittaker 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1473 

EPA Comment ID: 20482 

EPA Comment Code: 6120 

 

Comment: I am writing in support of maintaining high standards of water purity -- keeping 

perchlorate OUT of drinking water. Friends and family suffer from thyroid problems and 

perchlorate has been linked to thyroid problems. DO NOT RELAX any standards that would allow 

perchlorate in our drinking water. Richard, Alison & Henry Whittaker 103 Marin Street San Rafael 

CA 94901 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1474 

EPA Comment ID: 20483 

EPA Comment Code: 6120 

 

Comment: PLEASE reconsider your position on Perchlorate. While the pharmaceutical companies 

may like things just the way they are, we have to protect the public, especially children. With all the 

endocrine and other health problems plagueing this country, we need to reduce the amount of 

toxins that go into our bodies. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 758 of 1099

Commenter Name: Ann Galbraith Miller 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1477 

EPA Comment ID: 20484 

EPA Comment Code: 6120 

 

Comment: Good Day, I am writing to urge you to disallow perchlorate in drinking water sources 

because it can create more impacts on human health than previously recognized. Since it your 

mission to protect public health, it seems obvious that you would act now to pull back on the 

decision to allow "safe" levels of this dangerous threat. Thank you, Ann Galbraith Miller 

Response: See response to comment code 6120. 

Commenter Name: Susan Dunham 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1478 

EPA Comment ID: 20485 

EPA Comment Code: 6120 

 

Comment: Please reconsider the consequences of not regulating perchlorate. Is this water you will 

be drinking? Is this water your family will be drinking? If it were, would you be making this decision 

knowing the harmful effects perchlorate can have on the health of the people who are exposed to it. 

We have had enough with the past administration looking the other way in other situations. Let's not 

continue down the same road. You are the individuals that Americans hold responsible for our 

health and well being. If we can't count on you to do your jobs who can we count on? By choosing 

to support national regulations on public drinking water we know we can continue to trust you with 

health related issues. Please reverse your decision. 

Sincerely, Susan Dunham 

Response: See response to comment code 6120. 

Commenter Name: T. Bramwell 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1479 

EPA Comment ID: 20486 

EPA Comment Code: 6120 

 

Comment: we need percholate testing in our water, and we need to move toward the banning of 

percholate that is enhanced by man-made action, or lack of action. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1480 

EPA Comment ID: 20487 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 759 of 1099

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: T. O'Brien 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1484 

EPA Comment ID: 20488 

EPA Comment Code: 6120 

 

Comment: All possible steps need to be taken to eliminate or reduce to safe levels all contaminants 

in our drinking water. You need to protect our health. 

Response: See response to comment code 6120. 

Commenter Name: Molly P. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1486 

EPA Comment ID: 20489 

EPA Comment Code: 6120 

 

Comment: To the U.S. Environmental Protection Agency: I am a normal 30 year old professional 

woman from MN and was shocked and disgusted to learn about the EPA decided to not regulate 

perchlorate in drinking water. Please reverse your preliminary determination on setting a regulation 

for perchlorate in drinking water! It should be the goal of the EPA to protect the health and welfare 

of Americans, not to gamble with our future by allowing the contamination of our nation's water 

supply! In Minnesota we are now seeing the consequences of poor decisions like the one you are 

about to make. In many lakes and rivers it is no longer save to catch and eat fish, some waters are 

even unswimable. Consider the quality of limited resources you will be leaving for children and 

grandchildren. Do not take chances with something as critically important as keeping our nation's 

drinking water clean!! Thank you for your consideration, Molly P.,Minneapolis, MN 

Perchlorate FACTS: Perchlorate contamination is a nationwide problem and has health impacts at 

lower levels than previously thought; 

a national primary drinking water regulation would provide a meaningful opportunity to protect 

public health. 

Perchlorate is a harmful chemical used in rocket fuel, flares, and explosives. 

Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development and metabolism. 

Developing fetuses, infants and children with thyroid impairment may suffer mental retardation, loss 

of hearing and speech or deficits in motor skills. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 760 of 1099

EPA agrees that perchlorate has been found in 395 sites in 37 states, including 153 public water 

systems serving over 20 million people. Some estimates are even higher. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1490 

EPA Comment ID: 20490 

EPA Comment Code: 6120 

 

Comment: It is a generally acknowledged fact that our planet is suffering from the dangerous 

effects of human industrialization, most publicly understood as global warming. More and more 

people are working to become responsible stewards of the earth by consuming less, buying organic 

and recycling; all the while an insidious danger flows quietly beneath our feet. 

Perchlorate is an environmental danger widely known amongst scientific communities and 

government agencies, yet virtually unheard by the public. So much research has been done on the 

existence of perchlorate contamination in our water, food and milk supplies, and yet nothing is 

being done to regulate it. Much worse than a passive lack of action, is the very active suppression by 

certain U.S. agencies to protect their very specific interests, at the great expense to our country's 

environment and the health of those who inhabit it. 

The EPA's website is full of information on how to contribute to the health of the environment 

from our classrooms to our beaches, from "purchasing green" to reducing water waste. It's 

wonderful to see the EPA helping people to make a positive impact on an individual level. 

Isn't it time for the EPA to take a responsible stand and make the decision to regulate perchlorate in 

drinking water? Please, help protect the health of our people, ecosystems and future. Without water, 

we are nothing. 

Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1492 

EPA Comment ID: 20491 

EPA Comment Code: 6120 

 

Comment: As someone who now suffers from thyroid dysfunction after many years of normal 

thyroid function, I urge the EPA to reconsider their decision to allow perchlorate contamination in 

our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 761 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1494 

EPA Comment ID: 20492 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

1. As a consumer, I depend on the EPA to protect my health. 2. Perchlorate contamination is a 

nationwide problem and has health impacts at lower levels than previously thought; 3. Since even 

small amounts can impair development and metabolism, the EPA should err on the side of caution 

and keep perchlorate out of the water supply. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1495 

EPA Comment ID: 20493 

EPA Comment Code: 6120 

 

Comment: If we cannot be assured of CLEAN drinking water because of a lax EPA, this country is 

in serious trouble! 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1500 

EPA Comment ID: 20494 

EPA Comment Code: 6120 

 

Comment: All pollutants and contaminants to drinking water must be monitored and reported. 

Public interest demands this to protect the health of the public. Transparency is essential to good 

governance and to democracy itself. Perchlorate is in no way naturally found in water and is harmful 

to human health. The EPA must not lower standards. Its responsibility is to the public and not to 

particular industrial or corporate interests. 

Response: See response to comment code 6120. 

Commenter Name: R Cooper Jr. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1501 

EPA Comment ID: 20495 

EPA Comment Code: 6120 

 

Comment: Any foreign substance in our drinking water is serious and is not acceptable. 

"Perchlorate," a jet fuel additive, is pure negligence to be tolerated in public drinking water that is 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 762 of 1099

consumed and used for cooking and bathing purposes by innocent families and their children. We 

don't need deliberate health threats to our population to add to their already stressed state of health. 

Please consider the consequences and act on improving actions on this social issue. Every man, 

woman, and child is involved in this life threatening situation. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1502 

EPA Comment ID: 20496 

EPA Comment Code: 6120 

 

Comment: I am dismayed at the EPA's preliminary decision not to regulate perchlorate in drinking 

water. Perchlorate has been shown to inhibit proper function of the thyroid. As the father of a 

young son, and another child on the way, I am extremely concerned about dangerous chemicals 

present in our drinking water. Even a small reduction in thyroid function results in a loss of IQ, and 

increased behavioral problems. The EPA was on a sensible course to limit exposure to this 

dangerous chemical around 2002. I am appalled that the safety of our children is being ignored due 

to political considerations. I have been extremely upset at the course the EPA has taken over the last 

8 years, allowing the White House and politics to sway decisions that should be made based on 

science and for the health and safety of the American people. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1504 

EPA Comment ID: 20497 

EPA Comment Code: 6120 

 

Comment: We need regulation of perchlorate in our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: A.M. Guckin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1506 

EPA Comment ID: 20498 

EPA Comment Code: 6120 

 

Comment: I am very concerned about the safety of US public water drinking water supplies. Keep 

the perchlorate out of the water. Test for it. 

When contaminants are found, everyone in the region that uses that source for their household 

water needs to be informed and advised how to avoid consumption of the contaminants. We do not 

want to be forced to buy bottled drinking water - especially when we don't know what level of 

contaminants are permitted in the bottled water supply. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 763 of 1099

Thank you for your attention and please do all possible to insure that we have clean, safe drinking 

water. 

Response: This regulatory action does not affect testing requirements for perchlorate in local 

jurisdictions. Please See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1507 

EPA Comment ID: 20499 

EPA Comment Code: 6120 

 

Comment: I am asking the Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. We need to PROTECT 

OUR EARTH BECAUSE IT IS WHAT IS PROTECTING US. If we continue to violate and 

contaminate and pollute our earth, WE are the ones who suffer now and will suffer even more, until 

we make ourselves and other species totally extinct. 

Response: See response to comment code 6120. 

Commenter Name: D. Smythe 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1509 

EPA Comment ID: 20500 

EPA Comment Code: 6120 

 

Comment: The determination of whether to control the level of perchlorate contaminates in 

drinking water supplies by the EPA has taken at least six years. Drinking water, groundwater or soil 

in hundreds of locations in at least 43 states is polluted with perchlorates. In 2004, eight states had 

advisories for perchlorate in drinking water, ranging from 1 to 18 parts per billion. Given the 

geographical magnitude of the problem and the diversity of current regulation, it is imperative that 

we have a Federal standard to protect everyone in the United States equally. 

That standard should recognize the scientific study that has gone on to determine a safe level, and 

should not be politicized or modified to suit defense contractors. 

Please set a standard of no more than 2 parts per billion. 

Response: See response to comment code 6120. 

Commenter Name: L. Brooks 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1512 

EPA Comment ID: 20501 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 764 of 1099

Comment: Please make testing mandatory for Perchlorate in out drinking water. We need to be 

vigilent in maintaining our most valuable resources of fresh water vital to the good health of the 

general public. 

Response: This regulatory action does not affect testing requirements for perchlorate in local 

jurisdictions. Please see response to comment code 6120. 

Commenter Name: Nancy Stefanou 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1514 

EPA Comment ID: 20503 

EPA Comment Code: 6120 

 

Comment: As a citizen, I ask you to remember your responsibilities to 'protect' (as in the Agency 

name) public interests. The umbilical cords of newborns are already showing the presence of an 

alarming number of chemicals...preventing exposure is vastly preferable to damage control. Again, 

please remember who you serve. 

Thank you, Nancy Stefanou 2582 Black Pine Trail Troy, Mi 48098 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Lesley Cox 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1516 

EPA Comment ID: 20505 

EPA Comment Code: 6120 

 

Comment: Perchlorate exposure recommended by National Academy of Sciences and adopted by 

EPA is an RfD of 0.7 μg/kg bw/day, this is daily exposure level over a lifetime that is not expected 

to cause adverse health effects. We already know perchlorate is in some public drinking water 

systems and in some foods. It makes no obvious sense to ignore it. We have methods to test for 

detection, why not use them? EPA is our regulatory agency for protecting our country's drinking 

water. Do your job!!!! 

Lesley Cox Carrabelle, FL 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1517 

EPA Comment ID: 20506 

EPA Comment Code: 6120 

 

Comment: As a resident of Tewksbury, MA and a journalist, I urge that the EPA require 

perchlorate testing of drinking water. I know the potential dangers of perchlorate to women and 

infants due to an corporate dumping of perchlorate into the Merrimack River in Massachusetts in 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 765 of 1099

2004. That dumping went straight into Tewksbury's water supply, preventing residents from 

drinking the water for several weeks and costing the town a tremendous amount of money to locate 

the problem, stop the problem, and ensure the quality of the water. Testing public water supplies, 

particularly those drawn from rivers, ensures early detection of tainted water and early notification of 

at risk populations. Further, regular testing and early detection helps identify polluters early and stop 

the pollution. Not testing for perchlorate in the water supply is irresponsible from a public health 

and environmental perspective. 

Response: This regulatory action does not affect testing requirements for perchlorate in local 

jurisdictions. Please see the response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1519 

EPA Comment ID: 20507 

EPA Comment Code: 6120 

 

Comment: we do not want perchlorate in our drinking water. it is clear we need to punish those in 

the federal govt who are not taking steps to protect americans. i note that the dept of defense of our 

own govt is one of the worst polluters. those in charge at this agency should go to jail for their 

lifetimes for poisoning fellow americans. no perchlorate in our drinking water should be allowed. 

Response: See response to comment code 6120. 

Commenter Name: D.E. McKenney 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1524 

EPA Comment ID: 20508 

EPA Comment Code: 6120 

 

Comment: In 2004, Tewksbury Massachusetts had a perchlorate contamination that prohibited the 

use of our tap water. I understand the dangers of perchlorate and ask you to keep the testing 

requirement intact for our public drinking water supplies. Removal of the testing requirement would 

eliminate detection of perchlorate in the case of accidental or intentional contamination of drinking 

water supplies thereby endangering us all. 

Response: This regulatory action does not affect testing requirements for perchlorate in local 

jurisdictions. Please see the response to comment code 6120. 

Commenter Name: Chris Christensen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1535 

EPA Comment ID: 20509 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 766 of 1099

* perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; * a national primary drinking water regulation would provide a meaningful 

opportunity to protect public health. 

Perc is still used in a majority of clothes cleaners/laundries across the nation. I chose to switch 

cleaners as a result. It should not be part of our drinking water. 

Chris Christensen 1160 N. Beverly Lane Arlington HTs, IL 60004 

Response: See response to comment code 6120. 

Commenter Name: Beatriz Bofill 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1536 

EPA Comment ID: 20510 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought. A national primary drinking water regulation would provide a meaningful 

opportunity to protect public health. 

If we do not learn from our past mistakes, we are doomed to repeat our failures over and over. Not 

protecting Americans from this contaminant will only cause greater problems further down the road. 

Hopefully with the new administration, this will be a non issue and I won't have to waste my time 

writing about a no-brainer decision as to establish and enforce an MCL on perchlorate. 

Sincerely, Beatriz Bofill 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1540 

EPA Comment ID: 20511 

EPA Comment Code: 6120 

 

Comment: There are existing studies that prove exposures to perchlorate have adverse effects on a 

woman's thyroid. How can we allow this toxin into our drinking water when it is known to be 

harmful? 

According to a 2006 study by researchers at the centers for disease control and prevention (cdc), it 

was concluded that american women, particularly those with low iodine intake, may have reduced 

thyroid function due to perchlorate exposure. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 767 of 1099

Please do not allow this harmful toxin to be unregulated when it comes to our drinking water. 

Response: See the response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1541 

EPA Comment ID: 20512 

EPA Comment Code: 6120 

 

Comment: There is sufficient evidence to warrant the regulation of perchlorate in drinking water. 

Please do so. Regards. 

Response: See response to comment code 6120. 

Commenter Name: Virginia Schulman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1542 

EPA Comment ID: 20513 

EPA Comment Code: 6120 

 

Comment: I represent no organization, and no government agency at any level. I am a concerned 

citizen, parent, and grandparent, and what's more, I care about my own health as well. Perchlorate 

does not belong in our drinking water. It needs to be regulated. How many toxins have we allowed 

into our environment only to say, years later, "Oops! Now you have cancer. My bad!" We don't need 

to wait for years to say that perchlorate does not belong in our drinking water. We need to regulate it 

and keep it out of our water supplies. Doing nothing is not neutral; it's hostile to the people of the 

United States. In my book, that's treason. The EPA is supposed to protect us, not totally ignore our 

health on behalf of industry. 

Virginia Schulman Northampton, Massachusetts 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1543 

EPA Comment ID: 20514 

EPA Comment Code: 6120 

 

Comment: I agree that this substance should NOT be in our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1545 

EPA Comment ID: 20515 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 768 of 1099

EPA Comment Code: 6120 

 

Comment: Rocket fuel in our water supply is domestic terrorism! 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1546 

EPA Comment ID: 20516 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

The side effects of even a minor amount of this contaminate in our water supply can have serious 

effects on children and pregnant mothers. Please DO NOT let this opportunity pass to set up safe 

and effective regulations for our citizens 

Response: See response to comment code 6120. 

Commenter Name: Aaron J. Skoglund 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1547 

EPA Comment ID: 20517 

EPA Comment Code: 6120 

 

Comment: I am concerned about the allowance of dangerous chemicals like perchlorate in our 

drinking water. I think that everything possible should be done to keep our nation's drinking water 

pure and clean. I urge the EPA to reconsider its allowance of perchlorate in drinking water at any 

level. The citizens of this country need to know that our health and well being is the EPA's top 

priority. There should be next to no room for compromise on this principle. 

Sincerely, Aaron Skoglund Amherst, MA 

Response: See response to comment code 6120. 

Commenter Name: Thomas L. Schoaf 

Commenter Organization: Cities of Litchfield Park and Goodyear, AZ 

EPA Document ID: EPA-HQ-OW-2008-0692-1552 

EPA Comment ID: 20518 

EPA Comment Code: 6120 

 

Comment: November 5, 2008 Stephen L. Johnson, Administrator U.S. Environmental Protection 

Agency Ariel Rios Building 1200 Pennsylvania Avenue, N.W. Washington D.C . 20460 

Re:Preliminary Regulatory Determination on Perchlorate Docket ID No . EPA-HQ-OW-2008-0068 

Administrator Johnson: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 769 of 1099

We, the undersigned, represent the cities of Goodyear and Litchfield Park. Our communities are 

located in the West Salt River Valley area of metropolitan Phoenix in central Arizona and are 

impacted or threatened by the Phoenix- Goodyear Airport (PGA) North federal superfund site. The 

PGA North federal Superfund Site is an area of groundwater that has been impacted by TCE and 

perchlorate and it is this perchlorate contamination that prompts us to request that the EPA 

reconsider its determination and establish a national maximum contaminant level for perchlorate. 

By way of background, surface water supplies in Arizona are limited and are fully allocated. Thus, 

groundwater is a vital water resource in the arid southwest providing a reliable future municipal 

supply for our growing communities. It is of such importance that Arizona classifies all aquifers as 

drinking water aquifers. Arizona, as with many other states, adopts the federal maximum 

contaminant levels (MCLs) as its own drinking water standards. Arizona also establishes aquifer 

water quality standards for the protection of its aquifers. Since Arizona's aquifers are classified as 

drinking water aquifers, the established aquifer water quality standards are generally equivalent to the 

MCLs. 

Response: See response to comment code 6120. 

Commenter Name: Richard Mead 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1553 

EPA Comment ID: 20521 

EPA Comment Code: 6120 

 

Comment: The refusal of the EPA to regulate perchlorate in drinking water is an abrogation of the 

EPA's responsibilities. 

Perchlorate is known to cause health problems to infants and adults that can be fatal or lead to 

permanent life-long disabilities. 

Refusing to acknowledge this problem is tacit approval of those whose cause the pollution. The 

American tax payer is entitled to better protection than is currently provided, and should rightfully 

expect the EPA to manage this problem and hold the polluters accountable for cleaning up the 

problem and eliminating further contamination. 

Richard Mead 

Response: See response to comment code 6120. 

Commenter Name: Crystal D. Lay 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1557 

EPA Comment ID: 20522 

EPA Comment Code: 6120 

 

Comment: Comments submitted to Environmental Protection Agency regarding: Preliminary 

Regulatory Determination on Perchlorate in Drinking Water RIN 2040-ZA02 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 770 of 1099

I respectfully request EPAâ€TMs consideration of the following comment regarding RIN 2040-

ZA02: 

I would urge EPA to reconsider setting a maximum contaminant level for perchlorate in drinking 

water for several reasons: 

1. Perchlorate can interfere with the functioning of the thyroid gland causing serious health effects, 

especially in developing children. 

2. If not regulated, the daily perchlorate intake can easily exceed the RFD of 0.7 Âμg/kg. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1565 

EPA Comment ID: 20524 

EPA Comment Code: 6120 

 

Comment: Please regulate perchlorate in drinking water. This is a public health issue. This chemical 

can cause thyroid problems affecting growth and development. 

Response: See response to comment code 6120. 

Commenter Name: C. Kennedy 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1569 

EPA Comment ID: 20525 

EPA Comment Code: 6120 

 

Comment: I think that anything that is as harmfull as rocket fuel is to humans should be regulated 

in our drinking water no matter how many PPM are deemed acceptable. By not doing so there is a 

big loop hole where millions of americans are then subjected to something that they are unaware of 

and may cause serious health hazards. First - on a personal note my mother had Non Hodgekings 

Lymphoma. Our family is unsure of what may have caused this. We had a well and if our water was 

tested who knows what that test would find. Or for that matter when people are going through a 

healh crisis it is better to be sure nothing like this would be introduced or reintroduced in their 

system. Second- Is it not better to try and regulate now and not in the future when there may be 

reason to have a huge multi person lawsuits. Does anyone really want to drink any persent of rocket 

fuel, maybe you folks at the EPA do but I don't! Thank you for your attention to this matter. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1570 

EPA Comment ID: 20526 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 771 of 1099

EPA Comment Code: 6120 

 

Comment: I urge the EPA to reverse it's decision re: perchlorate regulation. We now know that it 

has health impacts at lower levels than was previously recognized; with regulation public health 

could be protected. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Karen Cornelius 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1576 

EPA Comment ID: 20527 

EPA Comment Code: 6120 

 

Comment: I am writing to urge the U.S. Environmental Protection Agency to reverse its 

preliminary determination on setting a regulation for perchlorate in drinking water. I think no doing 

so puts people's health at risk, even at low levels. It can impair the thyroid gland. This could be 

especially harmful to developing fetuses, infants and children with thyroid impairments. I heard it 

has been found in sites in 37 different states. This is way too many. (For me, anyone would be too 

many.) Please protect the health of vulnerable citizens. Thank you for your consideration. Karen 

Cornelius 

Response: See response to comment code 6120. 

Commenter Name: M. Maguire 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1577 

EPA Comment ID: 20528 

EPA Comment Code: 6120 

 

Comment: Please protect the American public and keep perchlorate out of our drinking water. 

Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1579 

EPA Comment ID: 20529 

EPA Comment Code: 6120 

 

Comment: There shouldn't be any perchlorate in our drinking water. Please reconsider the decision 

not to regulate this chemical. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 772 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-1582 

EPA Comment ID: 20530 

EPA Comment Code: 6120 

 

Comment: Please regulate Perchlorate levels in our drinking water...We don't need any more 

potentially hazardous chemicals in our life sustaining water. 

Response: See response to comment code 6120. 

Commenter Name: Josephine Primeau 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1583 

EPA Comment ID: 20531 

EPA Comment Code: 6120 

 

Comment: Please, no Perchlorate in our drinking water! The risks to the public health far outweigh 

any argument to allow it. Please keep the well-being of the citizenry of the United States your 

priority rather than acting out of convenience. 

Respectfully, Josephine Primeau 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1585 

EPA Comment ID: 20532 

EPA Comment Code: 6120 

 

Comment: I have heard that the EPA is considering the deregulation of perchlorate in our water 

systems. I do not know what to believe and cannot imagine that this is true. I know that many of us 

would like clarification. If this is true, I am against it. Thank you. 

Response: On October 10, 2008 EPA published in the Federal Register a preliminary determination 

that a national primary drinking water rule was not necessary for perchlorate. However, EPA has 

now decided to regulate perchlorate in drinking water. See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1587 

EPA Comment ID: 20533 

EPA Comment Code: 6120 

 

Comment: Please do not deregulate PERCHLORATE in drinking water. We must protect our 

water and our environment. Isn't that the function of the EPA protect our land and water? Isn't that 

why we the people created the EPA? Companies are not good at policing themselves.Just do the job 

you are suppose to do! Please do not go in the same direction as the Federal Reserve did with the 

banking!! 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 773 of 1099

Response: See response to comment code 6120. 

Commenter Name: Amanda Forys-French 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1591 

EPA Comment ID: 20534 

EPA Comment Code: 6120 

 

Comment: To Whom it Concerns: It is hard for me to believe that anyone in their right mind 

would allow a substance such as perchlorate to remain in our water. I urge you as a consumer of 

water to please regulate perchlorate for my sake, for the sake of my family and all of America. We 

have enough worries as to what may be in our food and water and this does not need to be another 

one. Please help! Thank you, Amanda Forys-French 

Response: See response to comment code 6120. 

Commenter Name: Robin M. Chambers 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1592 

EPA Comment ID: 20535 

EPA Comment Code: 6120 

 

Comment: I am hoping that the new administration will take more interest in providing me an 

healthy enviroment . The EPA has not done anything for the last eight years to further this cause . I 

am one of very many who does not want Perchlorate in my drinking and more importantly in my 

childrens and grand childrens who will have have a long exposure to it .Please do what the agency 

was set up to do that is provide us with a safe enviroment . Thank you Robin M Chambers 

Response: See response to comment code 6120. 

Commenter Name: A. White 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1596 

EPA Comment ID: 20536 

EPA Comment Code: 6120 

 

Comment: please keep us safe from harmful cemicals.. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Jan Bourdelle 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1597 

EPA Comment ID: 20537 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 774 of 1099

Comment: Hello, please do not allow perchlorate contamination in our water. I have thyroid issues 

as do many, many people. The medicine for it is a permanent life long commitment. As many of us 

cannot afford healthcare, it will cause that much more of a financial burden on our citizens to 

support their impaired thyroids due to this chemical's present in our drinking water. Thank you. 

Jan Bourdelle, 458 Gail Dr., Nazareth PA 18064 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1598 

EPA Comment ID: 20538 

EPA Comment Code: 6120 

 

Comment: no perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: B. A. Provost 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1603 

EPA Comment ID: 20539 

EPA Comment Code: 6120 

 

Comment: Too many environmental protections have been lost in the last 10 or so years and we 

certainly can not afford to be further concerned about the safety of our drinking water. To allow 

something as hazardous to health as perchlorate in our water should call for anyone involved in 

EPA or the Bush administration orchestrating these criminal acts to be prosecuted in court. It is 

indeed a criminal act to allow an agent of death to be harbored in the water we must all have to 

survive. Governments have pursued the removal of trans-fats and nicotine from the public scene 

and turn around and let this go on. Such a travesty! 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Van Landuyt 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1608 

EPA Comment ID: 20540 

EPA Comment Code: 6120 

 

Comment: No to perchlorate in tap water. Need a citizen ask? 

Response: See response to comment code 6120. 

Commenter Name: Anonymouos 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1610 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 775 of 1099

EPA Comment ID: 20541 

EPA Comment Code: 6120 

 

Comment: Every adult and child deserves to have clean drinking water. The health consequences of 

contaminants is not fully known so we need to be vigilant. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1612 

EPA Comment ID: 20542 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. Perchlorate causes too many 

harmful effects to humans in even small amounts. As a tax paying and contributing citizen of this 

country I have a right to safe drinking water. In the future, as I decide to have a family, I want my 

children to have access to safe drinking water, not water that could cause them to have birth defects 

or negative consequences to their health. Please don't allow perchlorate in our water. Thank you for 

your time. 

Response: See response to comment code 6120. 

Commenter Name: Elise Sullivan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1613 

EPA Comment ID: 20543 

EPA Comment Code: 6120 

 

Comment: Please limit the amount of percholate allowed in our water. As a family physician, I am 

concerned about medical effects, such as affecting thyroid function by this chemical. Thank you, 

Elise Sullivan, M.D. Santa Rosa, CA 

Response: See response to comment code 6120. 

Commenter Name: S. L. Jackson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1614 

EPA Comment ID: 20544 

EPA Comment Code: 6120 

 

Comment: I do NOT want perchlorate to be tolerated/ ignored in public drinking water supplies --

nor in water supplied to farms and animals. 

For that matter, I don't want rocket fuel to be polluting the air I have to breathe, either, but I guess 

this battle against killer chemicals must be waged one painful step at a time. S.L. Jackson Randolph, 

NJ 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 776 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1617 

EPA Comment ID: 20545 

EPA Comment Code: 6120 

 

Comment: To not monitor and regulate potentially toxic substances in drinking water endangers 

the well being of all organisms that ingest the substance. I urge the EPA to carry out its mandate 

protecting the health of the American People. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1618 

EPA Comment ID: 20546 

EPA Comment Code: 6120 

 

Comment: Please regulate perchlorate in our drinking water!!! I'm very concerned with the 

pollutants found increasingly in our drinking water. Drugs, MTBE, perchlorate, pesticides.....how are 

our children going to survive all this? Are these chemicals harming our children, do we even know? 

Isn't it true that even in small amounts perchlorate can cause thyroid impairment? Please do 

everything you can to provide this country with safe water to drink. 

Response: The statement regarding drugs, MTBE, and pesticides fall outside the scope of this 

regulatory action. Regarding the remainder of the comment, please see the response to comment 

code 6120. 

Commenter Name: Denise F. Sipple 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1621 

EPA Comment ID: 20547 

EPA Comment Code: 6120 

 

Comment: To: Stephen L. Johnson, Administrator, EPA From: Denise F. Sipple, Rumson, NJ Re: 

Enforceable limits for perchlorate in our drinking water 

I recently lost my only child to cancer. Please protect the health of millions of American families and 

set enforceable limits for perchlorate in our drinking water. Specifically, I am writing to urge you 

reverse EPA's preliminary regulatory determination and set a protective drinking water standard for 

perchlorate as required by the Safe Drinking Water Act. 

Perchlorate contamination in our food and water supplies is too widespread, and its toxic effects too 

well known, for continued inaction on this problem. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 777 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1623 

EPA Comment ID: 20549 

EPA Comment Code: 6120 

 

Comment: It is a failure in your role to protect the people of the US that you want to no longer 

regulate perchlorate. The point at which you will begin to regulate it again in the future will most 

likely be because of a tragic foreseen incident. We all know that awareness, prevention, and action 

now prevents future complications. Please do the right thing and act accordingly. 

Response: See response to comment code 6120. 

Commenter Name: D. Brown 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1624 

EPA Comment ID: 20550 

EPA Comment Code: 6120 

 

Comment: Please keep Perchlorate out of our drinking water. It is known to be harmful in very 

slight concentrations, and has been found in numerous water systems throughout the country. I urge 

the EPA to honor its responsibility to protect the public by regulating this substance. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1626 

EPA Comment ID: 20551 

EPA Comment Code: 6120 

 

Comment: Please regulate perchlorate in our water. Your mandate is to protect the environment 

and the citizens of this country, and this kind of substance entering the bodies of children can't be 

permitted. 

Response: See response to comment code 6120. 

Commenter Name: Janet Ryan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1627 

EPA Comment ID: 20552 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. Please consider the harm 

that this decision could have on the public's health. Thank you. Janet Ryan 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 778 of 1099

Response: See response to comment code 6120. 

Commenter Name: M. A. Mulligan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1628 

EPA Comment ID: 20553 

EPA Comment Code: 6120 

 

Comment: How can the EPA not regulate perchlorate in drinking water? It is known to impair the 

thyroid gland, affecting growth, development and metabolism, and it has been found in public water 

systems across the nation. I urge you to reverse this decision. 

Response: See response to comment code 6120. 

Commenter Name: J. Sprance 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1629 

EPA Comment ID: 20554 

EPA Comment Code: 6120 

 

Comment: Why would you NOT regulate against Rocket Fuel in drinking water? I would like to 

understand what possible rationale there could be FOR allowing Rocket Fuel in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1429 

EPA Comment ID: 20557 

EPA Comment Code: 6120 

 

Comment: Really - there are enough health problems that need addressing in this country - autisim 

is just one example (I had never even heard of it as a child, currently though it's statistically on the 

increase). So, when there are health issues that can be addressed, and whose numbers can be keep 

lower, deregulation makes no sense. I'd like to hear anyone of you explain it to your children if your 

grandchild had mental retardation, or any other birth deficit, from the neglect you had in casting 

your vote against deregulation. Our clean waters must always be protected. Make your vote count - 

for the future generations! It may be your child and your grandchild that will be thanking you. 

Response: See response to comment code 6120. 

Commenter Name: Kathryn Murray 

Commenter Organization: North Shore Unitarian Church 

EPA Document ID: EPA-HQ-OW-2008-0692-1447 

EPA Comment ID: 20558 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 779 of 1099

Comment: Keep our drinking water clean! 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Nancy Yoke 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0621 

EPA Comment ID: 20559 

EPA Comment Code: 6120 

 

Comment: Water Docket Environmental Protection Agency Mailcode: 2822T 1200 Pennsylvania 

Ave., NW Washington, DC 20460 

Docket Identification (ID) Number: EPA-HQ-OW-2008-0692 Preliminary Regulatory 

Determination on Perchlorate Re: Request for extension of comment period 

I have a friend whose son was just diagnosed with Hashimoto's Disease, a disease of the thyroid. 

This is a potentially serious condition brought on by what? -- He is only 16! He has nodules on his 

thyroid -- something is causing this problem and since he lived on a naval base for several years, he 

has been exposed to this awful chemical Perchlorate in larger doeses. THIS IS SERIOUS AND WE 

NEED OUR GOVERNMENT AGENCIES TO WAKE UP! Quit protecting those at fault and do 

the right thing -- PROTECT OUR CHILDREN!!!! 

Response: See response to comment code 6120. 

Commenter Name: Samuel A. L. Perry 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1604 

EPA Comment ID: 20562 

EPA Comment Code: 6120 

 

Comment: Dear EPA Staff, 

As a drinking water professional, I generally abhor new regulations, but a national MCL on 

perchlorate is one thing that makes sense to me. After all, it occurs in drinking water at levels of 

public health concern far more often than than nearly any other chemical regulated under the 

SDWA, the two notable exceptions are arsenic and nitrate. If the same logic applied to perchlorate 

were applied to TCE, TCE would never have been regulated. 

Response: See response to comment code 6120. 

Commenter Name: James Hartman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1631 

EPA Comment ID: 20575 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 780 of 1099

Comment: Industrial chemicals do not belong in our water supply. Obviously it is not possible to 

eliminate all traces of such from the public water supply, but electing to NOT regulate perchlorate is 

irresponsible and threatens public health. There is ample evidence that, unregulated, this chemical 

poses a significant risk to the public. Please reverse your preliminary decision on this matter. 

Thank you, 

James Hartman 

Response: See response to comment code 6120. 

Commenter Name: Marc H Lavietes 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1633 

EPA Comment ID: 20576 

EPA Comment Code: 6120 

 

Comment: Perchlorate is poison and should not be in drinking water. 

Marc H Lavietes MD 

Response: See response to comment code 6120. 

Commenter Name: Andrea Kintree 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1635 

EPA Comment ID: 20577 

EPA Comment Code: 6120 

 

Comment: To Whom It May Concern, 

Please monitor and regulate/strictly limit the amount of perchlorate in the water. Only the 

government has the authority to keep an eye on these things. I look at what happens in other 

countries where things aren't regulated, or the government people don't do their jobs, and the water 

situation is a mess. I don't want that to happen here. 

Respectfully submitted, Andrea Kintree 

Response: See response to comment code 6120. 

Commenter Name: Gladys Poorte 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1636 

EPA Comment ID: 20578 

EPA Comment Code: 6120 

 

Comment: I live in Austin, Texas and have learned that Texas is one of the states where perchlorate 

is found in the water. I have a 20 year old daughter that has recently developed thyroid problems. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 781 of 1099

There is no genetic history of thyroid problems in our family. Perchlorate, even in small amounts 

can impair the thyroid gland. 

I've also learned that developing fetuses, infants and children with thyroid impairment may suffer 

mental retardation, loss of hearing and speech or deficits in motor skills. 

EPA agrees that perchlorate has been found in 395 sites in 37 states, including 153 public water 

systems serving over 20 million people. Some estimates are even higher. 

I urge the U.S. Environmental Protection Agency to reverse its preliminary determination on setting 

a regulation for perchlorate in drinking water. 

Please, protect our children!!! 

Gladys Poorte 

Response: See response to comment code 6120. 

Commenter Name: Edward Klutz 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1638 

EPA Comment ID: 20579 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Edward Klutz 

Response: See response to comment code 6120. 

Commenter Name: Janet Draper 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1640 

EPA Comment ID: 20580 

EPA Comment Code: 6120 

 

Comment: Dear Sir: 

I hope you will reverse the preliminary decision of the EPA not to regulate perchlorate in drinking 

water. Such a decision does not protect me and millions of other Americans from a toxic substance. 

We rely upon you you to protect us. 

Thank you for your consideration of my plea. 

Sincerely, 

Janet Draper 1825 Dunedin Ave. Duluth, MN 55803 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 782 of 1099

Response: See response to comment code 6120. 

Commenter Name: Laura Reiley 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1641 

EPA Comment ID: 20581 

EPA Comment Code: 6120 

 

Comment: Please fight for the right to have regulations restricting what is allowed to be dumped 

into our water ways. 

Perchlorate contamination in the drinking water is unexceptable at any level. 

You are my voice and I am saying NO to perchlorate. 

Kind Regards, Laura Reiley 

Response: See response to comment code 6120. 

Commenter Name: Janine Ambrose 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1645 

EPA Comment ID: 20582 

EPA Comment Code: 6120 

 

Comment: My question? 

Why do I even need to write you about putting rocket fuel in our water. We have elected you 

because of your intelligence and support of the people. Please observe what is coming in front of 

you, and do what is best for the people! 

Thanks for your time, Janine Ambrose 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1646 

EPA Comment ID: 20583 

EPA Comment Code: 6120 

 

Comment: I urge the EPA to reconsider and reverse their decision about Perchlorate. It is harmful 

to our population's health and should not be allowed in our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Beth Adams 
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Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1648 

EPA Comment ID: 20584 

EPA Comment Code: 6120 

 

Comment: Percholoriate must be regulated out of our drinking water and soon! 

We all know the hazardous effects of this dangerous chemical. Let's ban its use and keep our water 

safe for all generations! 

Thank you! 

Beth Adams 

Greenfield, MA 

Response: See response to comment code 6120. 

Commenter Name: Susan R. Kepner 

Commenter Organization: New Hampshire House of Representatives 

EPA Document ID: EPA-HQ-OW-2008-0692-1653 

EPA Comment ID: 20585 

EPA Comment Code: 6120 

 

Comment: As a state representative serving on the Resources, Recreation, and Development 

commitee in the NH House, I am very concerned about the quality of our drinking water. I cannot 

understand your decision NOT to regulate the dangerous "perchlorate" in drinking water. Please rethink this and remember that YOU are supposed to be guarding the health and welfare of all 

Americans!! Rocket fuel is not healthy in any thing we drink!! Even low levels are a danger, especially 

to infants and fetuses! Who will benefit by this lack of regulation? What big business or agency is 

MORE IMPORTANT THEN THE HEALTH OF THE AMERICAN PUBLIC???? REGULATE 

PERCHLORATE!!!!!! 

Response: See response to comment code 6120. 

Commenter Name: S. Broder 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1656 

EPA Comment ID: 20586 

EPA Comment Code: 6120 

 

Comment: It's important to me that I can trust that our drinking water is clean and healthy, 

especially for my baby and small child, whose developing bodies are particularly vulnerable to 

chemicals. 

Response: See response to comment code 6120. 

Commenter Name: L. Thorp 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1660 

EPA Comment ID: 20587 

EPA Comment Code: 6120 

 

Comment: why can't we find a way for jet planes to remove excess fuel from their tanks without 

dumping the fuel on the ground? Sounds so simple, then we would not have dangerous levels of 

perchlorate in the ground water. I am apalled that this practice goes on. Your inept ability to see that 

this is a very real concern for people also amazes me. Pardon my forwardness, but my husband died 

from something related to this, and I am concerned that others may die needlessly because 

regulations are not either followed, or not created for the military which is the largest polluter in this 

country, and largest contributor to superfund sites throughout the country. My husband was an 

environmental engineer who worked on a superfund site, and I know first hand about groundwater 

contamination. His job was to clean up the sites! Please reconsider the measure that is being 

forwarded very seriously. 

Response: See response to comment code 6120. 

Commenter Name: Jimmy Spearow 

Commenter Organization: Sacramento Chapter, Physicians for Social Responsibility 

EPA Document ID: EPA-HQ-OW-2008-0692-1672 

EPA Comment ID: 20591 

EPA Comment Code: 6120 

 

Comment: We urge you to protect Americans' health by regulating perchlorate in drinking water in 

accordance with the Safe Drinking Water Act. Please set the MCL for perchlorate in drinking water 

at no greater than 1 ppb. 

Several states, including New Jersey, Massachusetts, and California have already addressed the issue 

of perchlorate in drinking water by either already setting or planning to set a MCL that is far lower 

than the current EPA recommendation. While none of these states have proposed a MCL as low as 

1 ppb, their standards would still be far more protective of public health than the current EPA 

recommendation. But beyond these state borders, millions of people drink perchlorate contaminated 

water and depend on the federal government to protect them. EPA must fulfill this responsibility. 

Please regulate perchlorate in drinking water at no greater than 1 ppb. 

Sincerely, 

Jimmy Spearow, Ph.D. Sacramento Chapter, Physicians for Social Responsibility 911 Pennsylvania 

Place, #3 Davis, CA 95616 jlspearow@sbcglobal.net 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1673 

EPA Comment ID: 20592 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 785 of 1099

 

Comment: This decision should be reversed. The public has the right to know what is in their 

drinking water. Think about our children and grandchildren. I want them to be healthy and to be 

aware of what they are putting in their bodies. Keep our water safe. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1674 

EPA Comment ID: 20593 

EPA Comment Code: 6120 

 

Comment: Hi, I am an ordinary citizen, but an educated one, and I am very dismayed at the idea 

that the EPA may not regulate perchlorate. I urge the EPA to continue to regulate this substance, 

which can be very detrimental to a human's thyroid gland and even more serious to children that are 

exposed. Keep our water clean! It's bad enough we have to deal with several exposures and 

pollutions. 

Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1676 

EPA Comment ID: 20594 

EPA Comment Code: 6120 

 

Comment: For heaven's sake, STOP THE MADNESS.......D you honestly think that this is 

okay.......Clean it up please and then keep it clean....No perchlorate in out water and keep out the 

other cooties. Thank you 

Response: See response to comment code 6120. 

Commenter Name: J. Mosman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1682 

EPA Comment ID: 20595 

EPA Comment Code: 6120 

 

Comment: Please re-consider your preliminary decision regarding perchlorate in drinking water. We 

need to protect our water resources; they are much more important than oil, gas, and coal! Without 

water of good quality, we will be faced with impossible problems, and it might be too late to correct 

them. Let's be pro- active, limit the amounts of perchlorate to an extremely tiny percentage, and not 

realize years from now there was a horrendous mistake made. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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We definitely need to protect future generations from problems associated with perchlorate, which 

links have been proven to exist. 

Please, do revise your position; water is essential, and it's been badly abused in the past. We 

definitely need to re-orient ourselves and protect our resources - our nation's well-being relies on it. 

Response: See response to comment code 6120. 

Commenter Name: N. Abercrombie 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1685 

EPA Comment ID: 20596 

EPA Comment Code: 6120 

 

Comment: Please enact legislation that will protect our freshwater system from contamination with 

pollutants. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: J. Miller 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1689 

EPA Comment ID: 20597 

EPA Comment Code: 6120 

 

Comment: Please reverse your decision to not regulate perchlorate in drinking water. Perchlorate 

contamination is a nationwide problem and has health impacts at lower levels than previously 

thought. I am concerned for my family and the environment. 

Response: See response to comment code 6120. 

Commenter Name: P. Paul 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1691 

EPA Comment ID: 20598 

EPA Comment Code: 6120 

 

Comment: This request is to ask you to seriously consider reversing your decision not to consider 

regulating perchlorate in drinking water. Since perchlorate is used for rocket fuel and studies have 

shown trace amounts can destroy the thyroid gland as well as thyroid inhibition in fetuses, the longrange costs for health care is phenomenal. From a logical perspective, it makes more sense to 

regulate perchlorate in drinking water before it becomes a national health and environmental diaster. 

Thank You 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 787 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-1692 

EPA Comment ID: 20599 

EPA Comment Code: 6120 

 

Comment: As a tax payer, I urge the government/EPA to continue the regulation of perchlorate in 

our drinking water. Our planet/bodies is already subjected to enough unregulated contaminates..... 

keep our drinking water as pure/safe as possible! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1695 

EPA Comment ID: 20600 

EPA Comment Code: 6120 

 

Comment: regulate perchlorate period. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1697 

EPA Comment ID: 20601 

EPA Comment Code: 6120 

 

Comment: Rocket fuel (perchlorates) wasn't an original ingredient of water and shouldn't be in it 

now! You can add it to your own water if you wish. However, I'd greatly appreciate your leaving it 

out of mine. Your job is to help protect the public, NOT big business. 

Response: See response to comment code 6120. 

Commenter Name: Lesley LeFevre 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1698 

EPA Comment ID: 20602 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. -Lesley LeFevre, PsyD 

Response: See response to comment code 6120. 

Commenter Name: Clark Sellars 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1699 

EPA Comment ID: 20603 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 788 of 1099

 

Comment: I urge the EPA to Regulate Perchlorate in our drinking water. If you don't do it NOW, 

it will have to be in the future costing ten times as much and many more water supplies degraded. 

Please think of the health of the public and the enviroment FIRST. Sincerly Clark Sellars 

Response: See response to comment code 6120. 

Commenter Name: L. Helfman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1700 

EPA Comment ID: 20604 

EPA Comment Code: 6120 

 

Comment: You should regulate perchlorate in our water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1701 

EPA Comment ID: 20605 

EPA Comment Code: 6120 

 

Comment: Gentlemen, 

Higher perchlorate levels in drinking water? You have got to be kidding. Rocket fuel does not 

belong in drinking water, at any level! 

Perchlorate is proven harmful to developing fetuses, infants and children and at lower levels than 

previously thought. Allowing perchlorate in drinking water is filfully negligent on your part. 

Please fulfill your responsibility to the people and environment. Performing your duty under the law 

if a very important job; please do not shirk it now. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1702 

EPA Comment ID: 20606 

EPA Comment Code: 6120 

 

Comment: I am very concerned about allowing any perchlorate into the water system. Please 

regulate this chemical and protect our water system. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 789 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1703 

EPA Comment ID: 20607 

EPA Comment Code: 6120 

 

Comment: I SUPPORT THIS COMMENT IN FULL. EPA HAS BEEN APPROVING FAR 

TOO MANY TOXIC POLLUTANTS FOR THE LAST 17YEARS, TURNING DOWN NONE 

FOR APPROVAL. THAT SHOWS NO DISCRIMINATINO ON THE PART OF THIS 

AGENCY AND NO PROTECTION FOR THE AMERICAN PUBLIC AND ITS CHILDREN. 

Response: This is not a comment, a response it not necessary. 

Commenter Name: Paul Einboden 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1704 

EPA Comment ID: 20608 

EPA Comment Code: 6120 

 

Comment: Please reconsider the preliminary determination on setting a regulation for perchlorate 

in drinking water. 

It is critical that harmful chemicals are not in the public drinking water. (That perchlorate not work 

its way into further drinking water systems). 

Thank you Paul Einboden St. Petersburg, FL 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1707 

EPA Comment ID: 20609 

EPA Comment Code: 6120 

 

Comment: I respectfully request that the EPA regulate perchlorate levels in water. There are certain 

chemicals that are permissible in the water supply; this is not one of them. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1708 

EPA Comment ID: 20610 

EPA Comment Code: 6120 

 

Comment: Please make the regulations stricter for the purity of our drinking water. There has been 

a substantial increase in childhood autism and other ailments in the last 20 years. Studies are 

continuing to try and find the causes of this, but why wait for the results to show that higher levels 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 790 of 1099

of toxins in the drinking water are to blame. Please, please be proactive in keeping the health and 

welfare of our children. 

Response: See response to comment code 6120. Commenter's statements are out of scope of this 

regulatory action. 

Commenter Name: MattHew C. Ford, Jr. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1710 

EPA Comment ID: 20611 

EPA Comment Code: 6120 

 

Comment: To Whom It May Concern, 

Keep Perchlorate out of our drinking water. 

Very truly yours, 

MattHew C. Ford, Jr., M.P.A. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1713 

EPA Comment ID: 20612 

EPA Comment Code: 6120 

 

Comment: No rocket fuel/Perchlorate in drinking water, please. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1716 

EPA Comment ID: 20613 

EPA Comment Code: 6120 

 

Comment: We do NOT want perchlorate in our drinking water!!!!!!! PLEASE don't be responsible 

for it happening. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1719 

EPA Comment ID: 20614 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 791 of 1099

 

Comment: Perchlorate is a chemical we know is harmful. Why would it be a lawful option to allow 

a chemical used in rocket fuel in drinking water? The chemical can impact human development and 

metabolism, even at low levels. Please consider our children and America's coming generations. 

Regulate Perchlorate in our drinking water and turn the decision to allow it around. 

Response: See response to comment code 6120. 

Commenter Name: S. Ultimo 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1722 

EPA Comment ID: 20615 

EPA Comment Code: 6120 

 

Comment: why is there any question on whether perchlorate should be regulated in drinking water 

? 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Carol Bigelow 

Commenter Organization: University of Massachusetts 

EPA Document ID: EPA-HQ-OW-2008-0692-1427 

EPA Comment ID: 20633 

EPA Comment Code: 6120 

 

Comment: Accordingly, docket ID No. EPA-HQ-OW-2008-0692 should not form the basis for 

national primary drinking water regulation. 

Considering these issues, we conclude that EPA has based its argument for not regulating 

perchlorate contamination in public water systems on a literature that is both limited and ill focused. 

We believe that EPA has not performed a sufficiently "thorough review" of the literature, that it has 

omitted important information, and that it has failed to perform its due diligence in the 

interpretation and analysis of the information that it did present. To correct this, EPA must employ 

the CDC study (Blount et al, 2006a) as the point of departure for RfD determination, and must 

focus on the neonate and infant as the most sensitive population. 

References 

Andersen S, Pedersen KM, Bruun NH, Laurberg P (2002) Narrow individual variations in serum 

T(4) and T(3) in normal subjects: a clue to the understanding of subclinical thyroid disease. J Clin 

Endocrinol Metab 87:1068-1072. 

Andersen S, Bruun NH, Pedersen KM, Laurberg P (2003) Biologic variation is important for 

interpretation of thyroid function tests. Thyroid 13:1069-1078. 

Auso E, Lavado-Autric R, Cuevas E, Escobar Del Rey F, Morreale De Escobar G, Berbel P (2004) 

A moderate and transient deficiency of maternal thyroid function at the beginning of fetal 

neocorticogenesis alters neuronal migration. Endocrinology 145:4037-4047. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell KL (2006a) Urinary perchlorate and 

thyroid hormone levels in adolescent and adult men and women living in the United States. Environ 

Health Perspect 114:1865-1871. 

Blount BC, Valentin-Blasini L, Osterloh JD, Mauldin JP, Pirkle JL (2006b) Perchlorate Exposure of 

the US Population, 2001-2002. J Expo Sci Environ Epidemiol. 

Chan S, Rovet J (2003) Thyroid Hormones in the fetal central nervous system development. Fetal 

and Maternal Medicine Review 14:177-208. 

Chopra IJ, Sabatino L (2000) Nature and sources of circulating thyroid hormones. In: The Thyroid: 

A Fundamental and Clinical Text, Seventh Edition (Braverman LE, Utiger RD, eds), pp 136-173. 

Philadelphia: Lippincott-Raven. 

Dohan O, Portulano C, Basquin C, Reyna-Neyra A, Amzel LM, Carrasco N (2007) The Na+/I 

symporter (NIS) mediates electroneutral active transport of the environmental pollutant perchlorate. 

Proc Natl Acad Sci U S A 104:20250-20255. 

Gilbert ME, Sui L (2006) Dose-dependent reductions in spatial learning and synaptic function in the 

dentate gyrus of adult rats following developmental thyroid hormone insufficiency. Brain Res 

1069:10-22. 

Gilbert ME, Sui L (2008) Developmental exposure to perchlorate alters synaptic transmission in 

hippocampus of the adult rat. Environ Health Perspect 116:752-760. 

Ginsberg G, Rice D (2005) The NAS Perchlorate Review: Questions Remain about the Perchlorate 

RfD. Environ Health Perspect 113:1117-1119. 

Ginsberg GL, Hattis DB, Zoeller RT, Rice DC (2007) Evaluation of the U.S. EPA/OSWER 

preliminary remediation goal for perchlorate in groundwater: focus on exposure to nursing infants. 

Environ Health Perspect 115:361-369. 

Goodman JH, Gilbert ME (2007) Modest Thyroid Hormone Insufficiency During Development 

Induces a Cellular Malformation in the Corpus Callosum: A Model of Cortical Dysplasia. 

Endocrinology. 

Greer MA, Goodman G, Pleus RC, Greer SE (2002) Health effects assessment for environmental 

perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake in 

humans. Environ Health Perspect 110:927-937. 

Herbstman J, Apelberg BJ, Witter FR, Panny S, Goldman LR (2008a) Maternal, infant, and delivery 

factors associated with neonatal thyroid hormone status. Thyroid 18:67-76. 

Herbstman JB, Sjodin A, Apelberg BJ, Witter FR, Halden RU, Patterson DG, Panny SR, Needham 

LL, Goldman LR (2008b) Birth delivery mode modifies the associations between prenatal 

polychlorinated biphenyl (PCB) and polybrominated diphenyl ether (PBDE) and neonatal thyroid 

hormone levels. Environ Health Perspect 116:1376-1382. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Heyerdahl S, Oerbeck B (2003) Congenital hypothyroidism: developmental outcome in relation to 

levothyroxine treatment variables. Thyroid 13:1029-1038. 

Kirk AB, Dyke JV, Martin CF, Dasgupta PK (2007) Temporal patterns in perchlorate, thiocyanate, 

and iodide excretion in human milk. Environ Health Perspect 115:182-186. 

Lavado-Autric R, Auso E, Garcia-Velasco JV, Arufe Mdel C, Escobar del Rey F, Berbel P, Morreale 

de Escobar G (2003) Early maternal hypothyroxinemia alters histogenesis and cerebral cortex 

cytoarchitecture of the progeny. J Clin Invest 111:1073-1082. 

Lewander WJ, Lacouture PG, Silva JE, Lovejoy FH (1989) Acute thyroxine ingestion in pediatric 

patients. Pediatrics 84:262-265. 

NRC (2005) Health Implications of Perchlorate Ingestion. In. Washington D.C.: National 

Academies Press. 

Oerbeck B, Sundet K, Kase BF, Heyerdahl S (2003) Congenital hypothyroidism: influence of disease 

severity and L-thyroxine treatment on intellectual, motor, and school-associated outcomes in young 

adults. Pediatrics 112:923-930. 

Pearce EN, Leung AM, Blount BC, Bazrafshan HR, He X, Pino S, Valentin-Blasini L, Braverman 

LE (2007) Breast milk iodine and perchlorate concentrations in lactating Boston-area women. J Clin 

Endocrinol Metab 92:1673-1677. 

Rovet JF (2002) Congenital hypothyroidism: an analysis of persisting deficits and associated factors. 

Child Neuropsychol 8:150-162. 

Scinicariello F, Murray HE, Smith L, Wilbur S, Fowler BA (2005) Genetic factors that might lead to 

different responses in individuals exposed to perchlorate. Environ Health Perspect 113:1479-1484. 

Selva KA, Harper A, Downs A, Blasco PA, Lafranchi SH (2005) Neurodevelopmental outcomes in 

congenital hypothyroidism: comparison of initial T4 dose and time to reach target T4 and TSH. J 

Pediatr 147:775-780. 

Selva KA, Mandel SH, Rien L, Sesser D, Miyahira R, Skeels M, Nelson JC, Lafranchi SH (2002) 

Initial treatment dose of L-thyroxine in congenital hypothyroidism. J Pediatr 141:786-792. 

Sharlin DS, Tighe D, Gilbert ME, Zoeller RT (2008) The Balance between Oligodendrocyte and 

Astrocyte Production in Major White Matter Tracts Is Linearly Related to Serum Total Thyroxine. 

Endocrinology 149:2527-2536. 

Steinmaus C, Miller MD, Howd R (2007) Impact of smoking and thiocyanate on perchlorate and 

thyroid hormone associations in the 2001-2002 national health and nutrition examination survey. 

Environ Health Perspect 115:1333-1338. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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van den Hove MF, Beckers C, Devlieger H, de Zegher F, De Nayer P (1999) Hormone synthesis 

and storage in the thyroid of human preterm and term newborns: effect of thyroxine treatment. 

Biochimie 81:563-570. 

Zoeller RT, Rovet J (2004) Timing of thyroid hormone action in the developing brain: clinical 

observations and experimental findings. J Neuroendocrinol 16:809-818. 

Response: EPA has determined to regulate perchlorate in drinking water (See response to comment 

code 6120). For further information about the RfD for perchlorate, please see the response to 

comment ID 28927 under comment code 2110. Regarding the comment for EPA to focus on the 

neonate and infant as the most "sensitive population," EPA published a Federal Register notice on 

August 19, 2009 seeking comments on additional approaches to analyzing data related to EPA's 

perchlorate regulatory determination. These comments were sought in an effort to ensure 

consideration of all the potential options for evaluating whether there is a meaningful opportunity 

for human health risk reduction of perchlorate through a national primary drinking water rule which 

included neonates and children. 

Commenter Name: Robert Howd 

Commenter Organization: California Environmental Protection Agency, Water Toxicology 

Section 

EPA Document ID: EPA-HQ-OW-2008-0692-1671 

EPA Comment ID: 20652 

EPA Comment Code: 6120 

 

Comment: We hereby petition EPA to rethink their alleged health-protective level for perchlorate, 

and their proposed decision not to regulate it in drinking water. Thank you for consideration of our 

comments. 

Sincerely yours, 

Robert A. Howd, Ph.D. Senior Toxicologist 

References 

Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell KL. (2006). Urinary perchlorate and 

thyroid hormone levels in adolescent and adult men and women living in the United States. Environ 

Health Perspect 114:1865-1871. 

Clewell RA, Merrill EA, Gearhart JM, Robinson PJ, Sterner TR, Mattie DR, Clewell HJ. (2007). 

Perchlorate and radioiodide kinetics across life stages in the human: using PBPK models to predict 

dosimetry and thyroid inhibition and sensitive subpopulations based on developmental stage. J 

Toxicol Environ Health Part A. 70:5 408-428. 

Greer MA, Goodman G, Pleus RC, Greer SE. (2002). Health effects assessment for environmental 

perchlorate contamination: The dose-response for inhibition of thyroidal radioiodine uptake in 

humans. Environ Health Perspect 110:927-937. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Kahn HD, Stralka K. (2008). Estimated daily average per capita water ingestion by child and adult 

age categories based on USDA's 1994-1996 and 1998 continuing survey of food intakes by 

individuals. J Expo Sci Environ Epidemiol May 14. [Epub ahead of print] 

NAS. (2005). Health implications of perchlorate ingestion. National Academy of Sciences, National 

Research Council. January 2005. 

OEHHA. (2004). Public Health Goal for perchlorate in drinking water. Office of Environmental 

Health Hazard Assessment, California Environmental Protection Agency, Oakland and Sacramento, 

CA. 

Steinmaus C, Miller MD, Howd R. (2007). Impact of smoking and thiocyanate on perchlorate and 

thyroid hormone associations in the 2001-2002 National Health and Nutrition Examination Survey. 

Environ Health Perspect 115(9):1333-1338. 

U.S. EPA. (2004). Estimated Per Capita Water Ingestion and Body Weight in the United States - An 

Update. U.S. Environmental Protection Agency, Washington, D.C. EPA-822-R-00-001. 

U.S. EPA. (2005). Guidance on Selecting Age Groups for Monitoring and Assessing Childhood 

Exposures to Environmental Contaminants. U.S. Environmental Protection Agency, Washington, 

D.C. EPA/630/P-03/003F. 

U.S. EPA. (2008). Inhibition of the Sodium-Iodide Symporter by Perchlorate: An Evaluation of 

Lifestage Sensitivity Using Physiologically-Based Pharmacokinetic (PBPK) Modeling. EPA/600/R08/106A. Docket No. EPA-HQ-OW-2008-0692-0076. 

Response: See response to comment code 6120. 

Commenter Name: Mic Stewart 

Commenter Organization: Metropolitan Water District of Southern California 

EPA Document ID: EPA-HQ-OW-2008-0692-1784 

EPA Comment ID: 20662 

EPA Comment Code: 6120 

 

Comment: In 2004, California's Office of Environmental Health Hazard and Assessment 

(OEHHA) adopted a public health goal (PHG) for perchlorate of 6 ppb. In October 2007, the 

California Department of Public Health (CDPH, formerly the Department of Health Services) 

adopted a primary drinking water standard (maximum contaminant level, MCL) of 6 ppb. 

Although California has its own MCL for perchlorate, a national drinking water standard would 

assist in the clean-up of hundreds of U.S. Department of Defense facilities in Southern California 

and around the country. Since the detection of perchlorate contamination throughout the southwest 

Region and in hundreds of local groundwater wells, Metropolitan, its member agencies, and the 

drinking water community have called on the EPA to make a regulatory determination on 

perchlorate consistent with the tenets of the Safe Drinking Water Act. 

Metropolitan wishes to offer the following comments: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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* Regulatory Determination - With EPA's determination not to regulate perchlorate and therefore 

not set a drinking water MCL, Metropolitan is concerned that without Federal regulation potential 

clean-up efforts of contaminated surface and groundwater sites throughout the region and other 

parts of the Country may be impaired. 

Response: See response to comment code 6120. 

Commenter Name: Stephen A. Owens 

Commenter Organization: Arizona Department of Environmental Quality 

EPA Document ID: EPA-HQ-OW-2008-0692-1785 

EPA Comment ID: 20666 

EPA Comment Code: 6120 

 

Comment: Numerous environmental, health and medical agencies, including the National Academy 

of Sciences, have documented and agreed that ingesting perchlorate through contaminated water, 

food and human breast milk may interfere with the production of thyroid hormones. This 

interference occurs because perchlorate "competes" with the uptake of iodide in the thyroid gland. 

Adding to this concern is EPA's own finding that the risk to infants is greater even when they have 

ingested low levels of perchlorate. Finally, the Centers for Disease Control found that ingesting 

perchlorate contaminated food and water may pose even a greater health threat for those women 

who have lower iodine intake levels to begin with. 

Based upon the known occurrences of perchlorate in Arizona's water supply coupled with known 

human health concerns at detected levels, ADEQ disagrees with EPA's preliminary decision not to 

regulate perchlorate and strongly encourages EPA to reconsider the determination. 

Thank you in advance for your consideration of these comments 

Sincerely, Stephen A. Owens Director 

Response: See response to comment code 6120. 

Commenter Name: Ann Ell 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1522 

EPA Comment ID: 20668 

EPA Comment Code: 6120 

 

Comment: To Whom it May Concern, As a Mother of two small children who had to deal with this 

problem recently, I urge you to take a good look at the regulations and make them as forceful as 

possible. sincerely, Ann M. Ell Tewksbury MA 

Response: See response to comment code 6120. 

Commenter Name: P. Impink 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1434 

EPA Comment ID: 20675 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 797 of 1099

EPA Comment Code: 6120 

 

Comment: Our whole town was not able to drink the water for 6 months when perchlorate was 

detected from discharge from another community. I was pregnant at the time. Please require 

municipal water suppliers to test for perchlorate. We just don't know the long term health effects of 

these contaminants. 

Response: See response to comment code 6120. 

Commenter Name: Sandra Clifford Teeple 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1730 

EPA Comment ID: 20677 

EPA Comment Code: 6120 

 

Comment: I am deeply concerned by the EPA's decision to allow perchlorate in public drinking 

water. While allowing this substance to remain may be an initial cost- saving issue for some 

businesses, in the long term, perchlorate COSTS America a great deal of money, time, effort, and 

resources. The damage to infants and small children is incalculable; the costs to medically care for 

and to remedially educate the children damaged by deliberate pollution, such as perchlorate, are also 

incalculable. 

Prevention is always CHEAPER than restoration and remediation! Please do not permit the 

pollution of our drinking water. Thank you for listening to my concerns. 

Sandra Clifford Teeple jsteep@aol.com 

Response: Please See response to comment code 6120. 

Commenter Name: Karen A. Vilandry 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1734 

EPA Comment ID: 20680 

EPA Comment Code: 6120 

 

Comment: Dear Mr. Johnson, 

With respect to the decision in Massachusetts to lower the perchlorate standard in drinking water, it 

only makes sense to do the same nationwide. 

http://www.boston.com/news/local/massachusetts/articles/2006/07/28/massachus 

etts_sets_state_standard_for_perchlorate/?p1=email_to_a_friend 

Drinking water needs to be in its purest form to protect public health. Please keep in mind, that 

already two thirds of the country is using hydrofluosilicic acid, (fluoride), a hazardous waste 

byproduct of the phosphate industry, in drinking water. By allowing another toxic chemical in the 

drinking water, it only exacerbates the problem even further creating quite a toxic cocktail of 

chemicals that humans don't need in their water source. Please act on behalf of all, protect the 

population and keep the water clean. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 798 of 1099

Thank you! Karen A. Vilandry "Wasted Away" 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1738 

EPA Comment ID: 20682 

EPA Comment Code: 6120 

 

Comment: Please reverse your decision on allowing the rocket fuel addative to be allowed in our 

drinking water. 

Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Denis Orpen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1739 

EPA Comment ID: 20683 

EPA Comment Code: 6120 

 

Comment: I have learned the dangers of perchlorate and ask you to help keep the requirement 

intact for our drinking water.Removal of the testing would eliminate detection in case of 

contamination. We in Tewksbury still recall the contamination of our water in 2004. 

Denis Orpen 51 Nina Dr Tewksbury 

Response: This regulatory action does not address any existing testing requirements for perchlorate 

in local jurisdictions. Please see response to comment code 6120. 

Commenter Name: L. Kuegler 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1740 

EPA Comment ID: 20684 

EPA Comment Code: 6120 

 

Comment: The testing of water for perchlorate is very important. As a resident of Tewksbury,MA I 

was subject to contaminated perchlorate drinking water and during that time I contracted 

hyperthyroidism. This has affected my life drastically. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1744 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 799 of 1099

EPA Comment ID: 20686 

EPA Comment Code: 6120 

 

Comment: testing for perchlorate is very important and should not be discontinued. I live in 

Tewksbury, Ma. We were unable to drink our water for months because of high levels of 

perchlorate. I have young children so my concern is for them. 

The side effects of perchlorate are scary so please do what is right and continue to test! 

Response: This regulatory action does not address testing requirements for perchlorate in local 

jurisdictions. Please see response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1745 

EPA Comment ID: 20687 

EPA Comment Code: 6120 

 

Comment: Although perchlorate levels have perhaps dropped to neglible levels in water supplies as 

a whole, in 2004 the tap water in Tewksbury, Massachusetts could not be consumed because of 

elevated perchlorate levels. In fact, this condition was ultimately isolated to dumping by a 

manufacturing facility upstream on the Concord River, which merges with the Merrimack River, 

from which Tewksbury's water is drawn. It has since been addressed, but consider the implications 

for residents of Tewksbury, and specifically for children, had the condition not been detected, I 

don't believe this is a reasonable risk to assume. I certainly would not want my three small children 

to be harmed by such a decision. 

Thank you. 

Resident of Tewksbury 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1746 

EPA Comment ID: 20688 

EPA Comment Code: 6120 

 

Comment: Please continue to test for Perchlorate and other chemicals in our drinking water. Right 

around the time the perchlorate was found, my neighbor was very sick with thyroid problems (in her 

40s) and I had to have chemotherapy at age 41 from a molar preganancy turned choriocarcinoma. 

People's health is nothing to mess around with. Health is wealth and we can't afford not to have 

clean air in water. Please be sure to test our water! 

MANY THANKS. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 800 of 1099

A concerned citizen of Tewksbury 

Response: This regulatory action does not address testing requirements for perchlorate in local 

jurisdictions. Please see response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1747 

EPA Comment ID: 20689 

EPA Comment Code: 6120 

 

Comment: umm how about we tighten water safety standards rather than making them more lax. 

Don't be [expletive] retarded. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: S. Franzeen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1753 

EPA Comment ID: 20690 

EPA Comment Code: 6120 

 

Comment: Perchlorate is a nasty little chemical. I'm not sure what the EPA's motivation is to not 

regulate the threat of perchlorate in our drinking water, but please add my voice in opposition to 

such a notion. Perchlorate must be regulated. 

Response: See response to comment code 6120. 

Commenter Name: E. Cruz 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1755 

EPA Comment ID: 20691 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. I live near a plant which 

releases perchlorate into the environment every day, and it is an ongoing concern for me and my 

family. 

Response: See response to comment code 6120. 

Commenter Name: Bruce P. Boxer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1756 

EPA Comment ID: 20692 

EPA Comment Code: 6120 

 

Comment: Please keep our water safe to drink. Regulate Percholates. Please Thanks, Bruce 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 801 of 1099

Response: See response to comment code 6120. 

Commenter Name: Ylana Stewart 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1757 

EPA Comment ID: 20693 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Perchlorate is used in rocket fuel, flares, and explosives. How can we possibly allow it to exist in our 

drinking water? The same water that our children drink. It is horrifying to think that the EPA does 

not consider regulation extremely important. Perchlorate, even in small amounts, can impair the 

thyroid gland, which controls growth, development and metabolism. Please protect us from this 

hazard. Sincerely, Ylana Stewart - Rockland, Massachusetts 

Response: See response to comment code 6120. 

Commenter Name: D.L. Humes 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1759 

EPA Comment ID: 20694 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on not regulating for perchlorate in drinking water. 

There is enough evidence showing a strong correlation between perchlorate and health problems. 

Please do the job your department was created for and protect the citizens of this country and the 

environment instead of large corporations and bowing to special interests that influence your 

department either directly or through congressmen who have been bribed through campaign funds. 

Pass regulations that will protect us today and tomorrow. 

Response: See response to comment code 6120. 

Commenter Name: Lynn Brown 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1760 

EPA Comment ID: 20695 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary decision on 

perchlorate levels in drinking water. This stuff has health impacts even at low levels. 

Young children would be especially be at risk. Please protect the public health. Let's move forward... 

not backward. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 802 of 1099

Lynn Brown 18 Foxcroft Rd. Niantic, CT 

Response: See response to comment code 6120. 

Commenter Name: Heather Hesse-Stromberg 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1763 

EPA Comment ID: 20696 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Heather Hesse-Stromberg 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1763 

EPA Comment ID: 20698 

EPA Comment Code: 6120 

 

Comment: As the mother of a 4 year-old, this kind of potential hazard frightens me to the core. 

There are enough threats to her good health and normal development without adding the one thing 

she is most encouraged to do (drink lots of water) to the list... 

Please reconsider your decision to not regulate perchlorate in the drinking water - the health of the 

next generation depends on it! 

Heather Hesse-Stromberg Rochester, NH 

Response: See response to comment code 6120. 

Commenter Name: D. Peters 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1764 

EPA Comment ID: 20699 

EPA Comment Code: 6120 

 

Comment: I am writing to urge the EPA to protect public health by increasing regulation of 

perchlorate in drinking water. Contamination can put may children and adults at risk for serous 

health problems. 

Response: See response to comment code 6120. 

Commenter Name: Agnes Merrick 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1771 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 803 of 1099

EPA Comment ID: 20700 

EPA Comment Code: 6120 

 

Comment: To the EPA, 

I am deeply concerned over your unethical attitude towards allowing perchlorate to contaminate our 

drinking water. If one of your own family members suffered a life-threatening disease or an 

incurable deformity from ingesting Rocket Fuel- tainted water, you would have to live with the fact 

that your moral laziness was the precipitating cause. 

Sincerely, Agnes Merrick 519 Yarmouth Rd. Baltimore, Md. 21286 

Response: This is not a comment, a response is not necessary. 

Commenter Name: N. Thakur 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1772 

EPA Comment ID: 20701 

EPA Comment Code: 6120 

 

Comment: ban perchlorate in drinking water 

Response: See response to comment code 6120. 

Commenter Name: S. Blackard 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1774 

EPA Comment ID: 20702 

EPA Comment Code: 6120 

 

Comment: As a citizen of the United states I count on the EPA to set regulations that keep our 

drinking water clean and healthy. Please set regulations to keep perchlorate and other potentially 

toxic chemicals out of our drinking water! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1777 

EPA Comment ID: 20703 

EPA Comment Code: 6120 

 

Comment: Clean drinking water is a limited natural resource - fought over in some regions - and is 

worthy of the full protection by the EPA. We must ensure that all business enterprises and 

municipalities are held to the highest siting and operating standards necessary to safeguard our water 

supplies. Of particular concern to me is the possibility of water contamination by perchlorate - an 

ingredient in rocket fuel. This must not be allowed to take place and the EPA must set strict 

contamination and testing guidelines. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 804 of 1099

Response: See response to comment code 6120. 

Commenter Name: Becky 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1778 

EPA Comment ID: 20704 

EPA Comment Code: 6120 

 

Comment: I am concerned about keeping our water safe and about allowing perchlorate intoour 

water supply. I believe that we should not have any perchlorate in our water. Becky 

Response: See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #7 – Group Unidentified 

EPA Document ID: EPA-HQ-OW-2008-0692-1518 

EPA Comment ID: 20705 

EPA Comment Code: 6120 

 

Comment: I understand the dangers of perchlorate and ask you to keep the testing requirement 

intact for our public drinking water supplies. Removal of the testing requirement would eliminate 

detection of perchlorate in the case of accidental or intentional contamination of drinking water 

supplies, such as the Tewksbury Massachusetts contamination in 2004. 

Response: See response to comment code 6120. 

Commenter Name: Daniel Green 

Commenter Organization: Green Machine Consulting, LLC 

EPA Document ID: EPA-HQ-OW-2008-0692-1783 

EPA Comment ID: 20706 

EPA Comment Code: 6120 

 

Comment: This is a dumb rule. Please reject it. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1790 

EPA Comment ID: 20707 

EPA Comment Code: 6120 

 

Comment: Test for and keep perchlorate out of our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: L. McPhedran 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 805 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-1791 

EPA Comment ID: 20708 

EPA Comment Code: 6120 

 

Comment: Please do not allow perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Karen Parelhoff 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1793 

EPA Comment ID: 20709 

EPA Comment Code: 6120 

 

Comment: I do not understand why you would not insist on regulating perchlorate in our water. I 

do not want rocket fuel in my drinking water in any amount, truthfully. At the very least I want it 

monitored and regulated. We know that there are health concerns associated with it especially for 

the unborn. Please put country first that means the health and well-being of our children and the 

rest of us should be your first concern. It irks me that I need to write this as it seems like such a nobrainer. Protect our water. Protect our health. 

Karen Parelhoff 6803 Glenmont St. Falls Church, Va. 22042 

Response: See response to comment code 6120. 

Commenter Name: L. Astur 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1803 

EPA Comment ID: 20711 

EPA Comment Code: 6120 

 

Comment: I urge the EPA to protect public health by regulating perchlorate in drinking water. 

This substance has been found in public drinking water supplies nationwide and is a serious threat 

the the health of fetuses, children, and adults. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1808 

EPA Comment ID: 20712 

EPA Comment Code: 6120 

 

Comment: I hope you do not deregulate the amount of perchlorate in drinking water. The drinking 

water should be clean to drink, not have trace amounts of rocket fuel in it. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 806 of 1099

Commenter Name: Ed O. Travis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1810 

EPA Comment ID: 20713 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. Perchlorate is a dangerous 

chemical, and the EPA owes citizens a decision base on the best available scientific data, with a 

margin of safety added to ensure protection of the public health in situations where there is not a 

consensus. 

Ed Travis Austin, TX 

Response: See response to comment code 6120. 

Commenter Name: Sierra Club 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1811 

EPA Comment ID: 20714 

EPA Comment Code: 6120 

 

Comment: Please re-visit. No perchlorate in water! 

Response: See response to comment code 6120. 

Commenter Name: Elanne Palcich 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1812 

EPA Comment ID: 20715 

EPA Comment Code: 6120 

 

Comment: As a citizen living within the U.S.A., I prefer not to have perchlorate in my water. I hope 

the EPA doesn't think it's ok to have perchlorate leaching into our water supplies. There must be 

some sort of EPA policy guidelines in place to protect citizens from toxic chemicals such as this. 

The issue seems to be following through with your mandate. 

Thanks. Elanne Palcich 29 SE 5th St. Chisholm, MN 55719 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1813 

EPA Comment ID: 20716 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 807 of 1099

Comment: Allowing such things as percolate, fluoride, drugs and other toxins in the water is 

rediculous. Do your job and protect the populous from these and other toxins. 

Response: Regarding regulating perchlorate in drinking water, see response to comment code 6120. 

Regarding regulation of "fluoride, drugs and other toxins in the water," no response is necessary as it 

is outside of the scope of this action. 

Commenter Name: Laurie Meisenheimer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1814 

EPA Comment ID: 20717 

EPA Comment Code: 6120 

 

Comment: Please, do as you need to and protect the environment for the people of the United 

States. That is your job. You need to reverse your decision not to regulate percholate. It would be 

negligent not to try to keep our waters free of this known dangerous chemical. As a teacher, I see 

many children who are not funtioning as they should. We need to do our best to keep them whole 

and healthy. Regulate percholate- keep us safe. That is what the EPA is for, and we all look to you to 

do what is right. 

Laurie Meisenheimer First Grade Teacher 

Response: See response to comment code 6120. 

Commenter Name: T. Morris 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1815 

EPA Comment ID: 20718 

EPA Comment Code: 6120 

 

Comment: On October 10, the EPA announced its preliminary decision not to regulate perchlorate 

in drinking water. Please reverse this decision and keep our water clean! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1817 

EPA Comment ID: 20719 

EPA Comment Code: 6120 

 

Comment: Even if at any point in time percolate isn't much of a threat it is possible that someone 

somewhere could have access to it and if it ends up in the water, not only would everyone want it 

detected but also somebody could be caught for illegal activity. 

Response: No response necessary, this is not a comment. 

Commenter Name: Regina Epp 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 808 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1820 

EPA Comment ID: 20720 

EPA Comment Code: 6120 

 

Comment: To whom it may concern: 

Regarding the allowance of perchlorate in drinking water--Please note that this substance affects 

metabolism at much lower levels that previously thought. I strongly urge you to protect our drinking 

water supply, which is quickly deteriorating in quality, from further contamination. My family and I 

are putting our faith in our government's assertion that the needs of ordinary people will not suffer 

when balanced with the desires of corporations. 

Sincerely, 

Regina Epp 

Response: See response to comment code 6120. 

Commenter Name: Noel Anderson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1822 

EPA Comment ID: 20721 

EPA Comment Code: 6120 

 

Comment: This is in regards to allowing percholate in our drinking water and not regulating it. As a 

person who has thyroid problems, I am highly concerned that the government would allow a 

chemical into our drinking water that would further compromise my health. For this reason I 

strongly urge you to ban percholate entirely from our water. 

Sincerely, 

Noel Anderson Quakertown, PA 

Response: See response to comment code 6120. 

Commenter Name: S. Elliott 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1823 

EPA Comment ID: 20722 

EPA Comment Code: 6120 

 

Comment: NO PERCHOLATE in our drinking water! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 809 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-1824 

EPA Comment ID: 20723 

EPA Comment Code: 6120 

 

Comment: Please reverse your preliminary determination concerning the amount of perchlorate in 

our drinking water. Our children have enough to face due to our poor choices. The wellness of our 

generation and those that follow will be directly affected by this decision and those similar. It is time 

we stop adding any chemicals that are not absolutely necessary to that which we ingest. There are 

other ways to solve these problems without exasperating our contribution to illness. 

Response: See response to comment code 6120. 

Commenter Name: Lois Fournier 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1825 

EPA Comment ID: 20724 

EPA Comment Code: 6120 

 

Comment: As a nurse for 40 years, I am concerned about public health. Clean water and clean air 

are basic rights that MUST be protected for the health of all peoples. To allow toxic chemicals like 

perchlorate in our drinking water at levels that cause problems, especially to those who are most 

vulnerable, is criminal. We can't expect to have productive citizens whose health is compromised. 

And we will burden society even more with costly, lifelong medical bills. Please toughen the laws on 

acceptable levels of perchlorate for everyone's sake. 

Lois Fournier Centerville, MA 

Response: See response to comment code 6120. 

Commenter Name: Robert A. Cloutier, Jr. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1832 

EPA Comment ID: 20725 

EPA Comment Code: 6120 

 

Comment: Please regulate perchlorate in drinking water. I do not want rocket fuel in my drinking 

water. 

Thank you, Robert A. Cloutier, Jr. 

Response: See response to comment code 6120. 

Commenter Name: M. Killian 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1834 

EPA Comment ID: 20726 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 810 of 1099

Comment: Please regulate our drinking water. Tell the EPA to keep perchloate out of the water. 

Do not allow jet fuel to seep into our supplies! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1837 

EPA Comment ID: 20727 

EPA Comment Code: 6120 

 

Comment: Please regulate and monitor drinking water for perchlorate contamination. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1839 

EPA Comment ID: 20728 

EPA Comment Code: 6120 

 

Comment: We should be tightening the standards for drinking water, not loosening them. 

Americans deserve safe, potable drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Michael Peterson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1841 

EPA Comment ID: 20730 

EPA Comment Code: 6120 

 

Comment: October 28, 2008 Water Docket Environmental Protection Agency Mailcode: 2822T 

1200 Pennsylvania Ave., NW. Washington, DC 20460. 

Dear Sir or Madam, 

I live in Los Angeles, CA and like many who live here, I am greatly concerned with the level of 

perchlorate in our water supply due to rocket fuel spillage. These worries have doubled recently as 

my wife and I are now planning to have our first child. 

While I understand there is conflicting evidence when it comes to the study of perchlorate, it is 

widely accepted that percholorate can negatively affect the thyroid in a mother which is essential for 

proper development of the fetal brain. 

No woman in the United States should be scared to drink tap water because she thinks it might 

cause damage to her unborn child. Rocket fuel has no place in our drinking supply IN ANY LEVEL 

- and certainly not at an increased level from what we used to believe was acceptable. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 811 of 1099

I trust you to do the right thing and require those who spill harmful chemicals in our water to pay 

for proper cleanup - and to keep "acceptable" levels of perchlorate as low as humanly possible. 

Sincerely yours, Michael Peterson 

Response: Regarding regulating perchlorate in drinking water, see response to comment code 6120. 

Regarding "requiring those who spill harmful chemicals in our water to pay for proper cleanup," see 

response to comment code 6300. 

Commenter Name: C. Rose 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1842 

EPA Comment ID: 20731 

EPA Comment Code: 6120 

 

Comment: Please do whats right 

Response: No response necessary, this is not a comment. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1843 

EPA Comment ID: 20732 

EPA Comment Code: 6120 

 

Comment: It is always astonishing how the people that pledged to defend the American people, 

plan to allow toxins and carcinogens flow through our drinking water. For what? A favor? My first 

child is due at the end of April. When you go to sleep tonight, think about my child and the 

regulations you are attempting to abandon. I wouldn't allow anyone to ever poison your child, why 

would you allow the poisoning mine? Why do you want to poison children? How can you live with 

yourself? My child, crying, because he has been poisoned thanks to your support of deregulation 

policies. 

Response: No response necessary, this is not a comment. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1844 

EPA Comment ID: 20733 

EPA Comment Code: 6120 

 

Comment: I grew up on Redstone Arsenal in Alabama(Aka Rocket City) and know first hand how 

damaging this chemical can be. My mother has had thyroid problems ever since my family moved 

there in 1984. Even though we only lived there for 5 years, and have zero history of thyroid 

problems in the family, she is now on medication for thyroid problems, and will be for the rest of 

her life. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 812 of 1099

To think that 20 years later, there is still zero regulation on Perchlorate is not only idiotic, but it is 

harming human health... The EPA has become a joke if you ask me under the Bush administration's 

last 8 years. It is their legal responsibility to protect American's from environmental harm, and yet 

here they are doing the exact opposite.. 

Why do i even pay taxes if this is what we get for our money? Should we honestly keep paying you 

to harm our loved one's health? 

This government needs to move back to being FOR the people, and NOT for the Corporations.... 

Response: No response necessary, this is not a comment. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1845 

EPA Comment ID: 20734 

EPA Comment Code: 6120 

 

Comment: I'm going to keep this as short and simple as possible. 

Americans as a whole are terribly overweight and have a tendency to put more than enough things 

into our bodies with a negative effect associated with them, 

Why would we not want to clean up our water as much as we can, especially if we can remove a 

cause of tyroid problems in children, unborn children and their mothers. 

It only makes sense to be willing to spend the time and money to better our water for the lives of 

our children. 

Response: No response necessary, this is not a comment. 

Commenter Name: Kenneth C. Moore 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1846 

EPA Comment ID: 20735 

EPA Comment Code: 6120 

 

Comment: Put the allowable limits of Perchlorate in drinking water back to what it was in 2002. I 

don't care what it costs to clean up; human beings, especially newborns, should not have to be 

exposed to the potential health reprocussions of this matter. It shall be the U.S. Government's #1 

priority to PROTECT and SERVE the citizens of the United States. Until the U.S. Government 

stops being persuaded by special interest groups, this country is NEVER going to see what it is truly 

capable of becoming; it will never see its TRUE potential. 

Kenneth C. Moore 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 813 of 1099

Commenter Name: Dennis W. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1849 

EPA Comment ID: 20738 

EPA Comment Code: 6120 

 

Comment: I think there should be stronger regulations on Perchlorate and a law that requires a 

clean up should be enacted. 

I lived next to a military base for 5 years and my wife went through three different pregnancies at 

that time. My research shows that Perchlorate can cause thyroid problems in pregnant women. 

During my wife's last pregnancy she developed a thyroid problem. My wife has to deal with a 

thyroid problem and we have to pay for thyroid medication for the rest of our lives possible because 

the EPA doesn't know how to do their job. There needs to be stronger legislation on this chemical. 

At least regulate it to the point of what was considered safe in 2002. 

Thank You Dennis W. 

Response: See response to comment code 6120. 

Commenter Name: M. Biro 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1850 

EPA Comment ID: 20739 

EPA Comment Code: 6120 

 

Comment: It is very important the the Agency is fully aware of the risks of allowing substances to 

be disposed in our water. It is expected that, while there is ANY doubt that harmful consequences 

may occur, the Agency void any additional permission. The Agency is supposed to always protect 

the interests of the population and never take any action for which the consequences are not fully 

understood, when authorizing the increase/release of chemicals on the environment. Therefore, 

based on your study, I do not believe the Agency has all the necessary elements to put this rule in 

effect, and it is the agency responsibility to void it. 

Response: See response to comment code 6120. 

Commenter Name: Charles Cronin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1852 

EPA Comment ID: 20741 

EPA Comment Code: 6120 

 

Comment: In regards to the changes on rules regarding perchlorate levels in drinking water, I 

believe the new changes should apply to only the area in and around Crawford, Texas, leaving the 

higher and safer standards for the bulk of the US citizenry! 

Thanks, Charles Cronin 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 814 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1853 

EPA Comment ID: 20742 

EPA Comment Code: 6120 

 

Comment: Please stop your midnight regulations that harm the environment and people. Citizens 

are more important than lobbyists (they just have more money.) Please represent the little guys and 

do what is best for us. 

Response: No response necessary, this is not a comment. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1854 

EPA Comment ID: 20743 

EPA Comment Code: 6120 

 

Comment: Perchlorate should be regulated at a level at or lower than the standard set in 2002, or at 

the set standard in California, which ever is lower. Raising this level is counter productive. 

Response: See response to comment code 6120. 

Commenter Name: Mi Sunyn 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1861 

EPA Comment ID: 20745 

EPA Comment Code: 6120 

 

Comment: 11/06/08 

Dear EPA, 

Please clean-up our water supply by restricting perchlorates 

Mi Sunyn 110 Roberts Ave #201 Alexandria, VA 22076 

Response: See response to comment code 6120. 

Commenter Name: J. Agee 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1862 

EPA Comment ID: 20746 

EPA Comment Code: 6120 

 

Comment: 11/06/08 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 815 of 1099

Dear EPA, 

Please do not put harmful chemicals in our water. 

J. Agee 850 N. Randolph St. Arlington, VA 22202 

Response: EPA does not intend to put harmful chemicals into our water, instead EPA has 

determined that perchlorate should be regulated in public water systems. See response to comment 

code 6120. 

Commenter Name: Tony Frangello 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1863 

EPA Comment ID: 20747 

EPA Comment Code: 6120 

 

Comment: 5 NOV 08 

TO WHOM IT MAY CONCERN 

I WOULD LIKE TO SUPPORT THE CLEAN WATER ACTION COMMITTEE EFFORTS 

TO RID OUR LOCAL WATER SUPPLY OF PERCHLORATE. 

TONY FRANGELLO 618 S. ROYAL ST. ALEXANDRIA, VA 22314 

Response: See response to comment code 6120. 

Commenter Name: D.O. Luttz 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1864 

EPA Comment ID: 20748 

EPA Comment Code: 6120 

 

Comment: 11/06/08 

Dear EPA, 

Please put a cap on perchlorates. Its polluting the and we don't need it. 

D.O. Luttz 8004 Candlewood Dr. Alexandria, VA 22306 

Response: See response to comment code 6120. 

Commenter Name: Peter S. Toney 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1865 

EPA Comment ID: 20749 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 816 of 1099

EPA Comment Code: 6120 

 

Comment: To the EPA 

To whom it may concern: 

I am a Virginia voter and am concerned about drinking water quality. Perchlorate is a dangerous 

chemical found in 37 states - we need to keep it out of our water supplies and it must be regulated. 

Sincerely, Peter S. Toney 

918 Green St. #1 Alexandria, VA 22314 

Response: See response to comment code 6120. 

Commenter Name: Jon 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1866 

EPA Comment ID: 20750 

EPA Comment Code: 6120 

 

Comment: 11/06/08 

Dear EPA, 

You guys need to keep perchlorate out of my drinking water. I water to live!!! 

Jon 6500 Hillview Ave. Alexandria, VA 22306 

Response: See response to comment code 6120. 

Commenter Name: Richard D. Weaver 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1867 

EPA Comment ID: 20751 

EPA Comment Code: 6120 

 

Comment: Water Docket, EPA, Mailcode 2822T 1200 Pennsylvania Ave Washington, D.C. 20460 

* ATTN: Docket ID No. EPA-HQ-OW-2008-0692 

To whom it may concern, 

I believe that the EPA should institute strict regulations on perchlorate in drinking water. I believe 

that there is strong evidence to suggest that it's presence in our drinking water is a significant risk to 

public health. There have not been sufficient routine tests on the effects of this chemical and it 

should be strongly regulated until such time as it is absolutely confirmed that it poses no significant 

health risk. Thank you. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 817 of 1099

Richard D. Weaver 

Response: See response to comment code 6120. 

Commenter Name: Robert S. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1869 

EPA Comment ID: 20753 

EPA Comment Code: 6120 

 

Comment: 11/05/08 

My drinking water 

To Whom it May Concern @ the EPA. Please keep perchlorate out of my water: a nationwide 

primary drinking water regulation is needed to protect our public health. I support the clean water 

action. 

Robert S. [Surname Illegible] 823 South Royal St Alexandria VA 22314 

Response: See response to comment code 6120. 

Commenter Name: Susan Willes 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1870 

EPA Comment ID: 20754 

EPA Comment Code: 6120 

 

Comment: 11/07/08 

Dear EPA, 

I do not want perchlorate or harmful chemcial in our water 

Susan Willes 110 Hume Ave Alex VA 22310 703-548-7762 

Response: See response to comment code 6120. 

Commenter Name: Janice Hollman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1871 

EPA Comment ID: 20755 

EPA Comment Code: 6120 

 

Comment: OW-2008-0692 

Attention EPA: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 818 of 1099

I, Janice Hollman, am concerned with the chemical, perchlorate, in our water system. Please use 

alternative chemcials in rocket fuel and explosives. It is very important. 

Sincerely, J Hollman 319 Hume Ave Alexandria, VA 22301 

Response: See response to comment code 6120. Regarding regulating use alternative rocket fuels, 

that is beyond the scope of this action. 

Commenter Name: Norman Howard 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1872 

EPA Comment ID: 20756 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

I Norman Howard am very much apposed to harmful chemical and deposit in our water system. 

Norman Howard 106 Hume Ave. Alex. VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Margaret S. Guryan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1873 

EPA Comment ID: 20757 

EPA Comment Code: 6120 

 

Comment: As a mother with an infant, I am very concerned about perchlorate in drinking water. 

Because of the harmful effects on children's development and fetuses, we need to limit this 

contamination in our drinking water. I urge the EPA to regulate this to keep our drinking water safe. 

Margaret S. Guryan 221 E. Oxford Ave Alexandria VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Meghan Hendy 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1874 

EPA Comment ID: 20758 

EPA Comment Code: 6120 

 

Comment: November 5, 2008 

Water Docket EPA Mailcode 2822T 1200 Pennsylvania Avenue Washington, DC 20460 

ATTN: Docket ID No. EPA-HQ-OW-2008-0692 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 819 of 1099

Dear Environmental Protection Agency: 

I am very disappointed in your announcement to not regulate perchlorate in drinking water and 

respectfully ask you to reconsider this decision. Perchlorate has been proven to be a harmful 

chemical and can impair the thyroid gland, especially impacting fetuses and children. I urge you to 

establish a federal exposure standard. 

Response: See response to comment code 6120. 

Commenter Name: Meghan Hendy 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1874 

EPA Comment ID: 20760 

EPA Comment Code: 6120 

 

Comment: As a mother of a toddler and a women in her childbearing years this is very concerning 

to me. We need a better federal tracking system for perchlorate and a higher exposure standard to 

protect our youngest citizens. Perchlorate contamination is a nationwide problem and has health 

impacts at lower levels than previously thought. It is imperative the the EPA implements a national 

primary drinking water regulation to protect public health. 

Thank you for your consideration. 

Sincerely, Meghan Hendy Alexandria, VA 

Response: See response to comment code 6120. 

Commenter Name: John Williams 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1875 

EPA Comment ID: 20762 

EPA Comment Code: 6120 

 

Comment: I don't want perchlorate in may drinking water 

John Williams 327 N. St. Asaph St. Alex., VA 

Response: See response to comment code 6120. 

Commenter Name: Sadea Ramsay 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1876 

EPA Comment ID: 20763 

EPA Comment Code: 6120 

 

Comment: 11/7/08 

To Whom it May Concern: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 820 of 1099

Perchlorate needs to be regulated by the EPA. Giving the federal government free reign to dump 

rocket fuel into our ground water is unacceptable. This is a huge threat to public health. This is a 

nationwide problem that needs to be addressed. Please put perchlorate contamination at the 

forefront of your drinking water regulations. 

Thank you, SADEA RAMSAY 2406 CLYDE AVE APT #4 ALEXANDRIA, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Will Arttey 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1877 

EPA Comment ID: 20764 

EPA Comment Code: 6120 

 

Comment: EPA water Docket, 

I work as a chef in VA, and I vote I believe that perchlorate is a dangerous chemical, since It has 

been found in 37 states, Presents a wide spread threat to our health, It get into water supply so It 

must be regulated. 

Sincerely Will Arttey 216 East Bellefonte Apt 1 Alexandria VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Andrew E. Stevenson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1878 

EPA Comment ID: 20765 

EPA Comment Code: 6120 

 

Comment: EPA Water Docket 

Dear Regulators: 

I am writing to express my support for increased federal regulation of perchlorate. It has serious 

health consequences - especially in young children; and shouldn't be given "a pass" as was recently 

done by the Bush Administration in its deal with the manufacturer. 

Response: See response to comment code 6120. 

Commenter Name: J. Sestak 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1879 

EPA Comment ID: 20767 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 821 of 1099

Comment: We need a national policy for regulating perchlorate in our drinking water. This 

chemical is dangerous to our youth in particular due to it's harmful effects on the thyroid gland. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1883 

EPA Comment ID: 20768 

EPA Comment Code: 6120 

 

Comment: I am outraged that EPA has not yet done its duty to protect the health of our families 

and communities from perchlorate pollution. This regulation must not be passed. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1886 

EPA Comment ID: 20769 

EPA Comment Code: 6120 

 

Comment: regulate perchlorate now 

Response: See response to comment code 6120. 

Commenter Name: Tina Donze 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1887 

EPA Comment ID: 20770 

EPA Comment Code: 6120 

 

Comment: Mr. Townsend, 

As a concerned citizen and mother of two children, I am appalled at the fact that the EPA would 

allow a chemical such as perchlorate to be in our drinking water. There are enough chemicals in our 

drinking water and air that we should spend more time and money cleaning it up rather than 

deciding if we should allow current levels to stay as they are. I don't care if I have to pay more taxes 

to have regulations tightened on the amount of pollution and contaminants a company is allowed to 

release into our environment. We only have one planet and we are not doing enough to take care of 

it and it's people. Please make sure that my children and there children can grow up in a safe 

environment free from all the unnecessary chemicals. Thank you. 

Sincerely, Tina Donze 

Response: See response to comment code 6120. 

Commenter Name: Rebecca Downey 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 822 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1888 

EPA Comment ID: 20771 

EPA Comment Code: 6120 

 

Comment: Rebecca Downey 1211 Hazel St Charlottesville, VA 22902-4908 

November 16, 2008 

Administrator Stephen L. Johnson 1200 Pennsylvania Ave ., N .W. Rm. 1101A Washington, DC 

20460 

Administrator Johnson: 

Dear Sir, 

As a physician I am very concerned as to the EPA is considering not setting a federal drinking-water 

standard for perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: M. Hoff 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1889 

EPA Comment ID: 20775 

EPA Comment Code: 6120 

 

Comment: As a resident of northern New Mexico, in a region where high amounts of perchlorates 

have been found in certain water tables, especially those ajacent to Los Alamos National Laboratory, 

I strongly object to the EPA proposal not to regulate this poisonous substance. I realize the EPA 

has been seriously in decline during this current administration and systematically shedding 

responsibility left and right from protecting the American public from the depredations of out-ofcontrol industries. But pretending a problem is not there will not make it go away. The EPA's 

shirking of responsibility makes it morally responsible for the health problems caused by its neglect. 

Please keep on regulating perchorates. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1890 

EPA Comment ID: 20776 

EPA Comment Code: 6120 

 

Comment: Increasing the amount of pollution allowed in our drinking water has no positive 

benefits to the public, however, it has a great benefit to industy and big business. Money, money, 

money they cry, in their smoked filled rooms, pollution is the name fo the game and big business are 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 823 of 1099

great at it. This rotten to the core president should be forced to drink the waters produced by big 

business manufacturing processes. 

Response: This is not a comment, no response necessary. 

Commenter Name: V. Foxx 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1892 

EPA Comment ID: 20777 

EPA Comment Code: 6120 

 

Comment: This type of action further illustrates how little the government cares about the people 

they allegedly serve. The midnight rules are illustrative of carelessness, recklessness and a total lack 

of compassion. If I ever see George W. Bush in person, he WILL take the time to hear me out. If he 

is lucky, he'll still have all his teeth when we are done. 

Response: No response necessary, this is not a comment. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1893 

EPA Comment ID: 20778 

EPA Comment Code: 6120 

 

Comment: I am not really sure why in the world this one would even pass, other than the fact that 

someone is getting paid a lot of money. If we as the public have any say so if this one passes, I want 

to make it very clear that I appose this proposal. It's not safe, it is putting innocent lives in danger, 

and it is uncalled for. If this is Bush's way of getting back at America, well then all I can say is, God 

help him. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1894 

EPA Comment ID: 20779 

EPA Comment Code: 6120 

 

Comment: I believe the safety of all people, especially children and pregnant women should be the 

first factor in deciding what contaminate levels are acceptable in drinking water. Bearing that in 

mind, I think all levels should be lowered never raised. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1895 

EPA Comment ID: 20780 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 824 of 1099

EPA Comment Code: 6120 

 

Comment: Our drinking water must be strictly regulated. Perchlorate is known to be harmful to 

one's health. How are you supposed to feel safe if you know your water could potentially contain 

harmful chemicals? Please regulate our water, and protect our parks and environment. You are doing 

a wonderful job as I can see, please keep it up. We are all counting on you. 

Response: See response to comment code 6120. 

Commenter Name: Tim Cranford 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1896 

EPA Comment ID: 20782 

EPA Comment Code: 6120 

 

Comment: The proposed relaxation of this standard is hazardous to the health and safety of 

millions of Americans. Rather than relaxing the standard, it would be much more advisable to 

decrease the "safe" levels of Perchlorate and bring them back down to the 2002 standard. Barring 

that, leave them as they are. None of us want to be drinking higher levels of this component of 

rocket fuel, nor do we want to be drinking higher levels of any other chemical. Drinking water in 

America should be clean. Anything less is unacceptable and puts the health of millions of Americans 

at risk. ~ Tim Cranford, US Citizen and Taxpayer 

Response: See response to comment code 6120. 

Commenter Name: Joe K. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1897 

EPA Comment ID: 20783 

EPA Comment Code: 6120 

 

Comment: One begins to question his/her faith in our government when money becomes more 

important than the well-being of those who reside within it's rule. I believe the correct choise is 

obvious and hope that any other level minded person would agree. 

~Joe K Redding, CA 

Response: No response necessary, this is not a comment. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1902 

EPA Comment ID: 20784 

EPA Comment Code: 6120 

 

Comment: I agree with Clean Water Action. I want my water clean! 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 825 of 1099

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1903 

EPA Comment ID: 20785 

EPA Comment Code: 6120 

 

Comment: Please keep perchlorate out of our drinking water! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1904 

EPA Comment ID: 20786 

EPA Comment Code: 6120 

 

Comment: Aren't there enough documented cases of health problems caused by contaminants in 

our water supply? Please do NOT allow perchlorate into our drinking water! Do your job and 

protect us! 

Response: See response to comment code 6120. 

Commenter Name: B. Pearlman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1907 

EPA Comment ID: 20787 

EPA Comment Code: 6120 

 

Comment: Please regulate to make perchlorate levels very low in the drinking water. These 

chemicals can have adverse effects on the thyroid gland depressing it's function and causing obesity. 

We don't need more causes of obesity in this country. 

Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Amelia Kroeger 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1909 

EPA Comment ID: 20788 

EPA Comment Code: 6120 

 

Comment: 6 November 2008 

The U.S. Environmental Protection Agency should reverse its preliminary determination on setting a 

regulation for perchlorate in drinking water. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 826 of 1099

Perchlorate contamination is a nationwide problem and clearly has health impacts at lower levels 

than previously thought; 

Give we citizens more serious consideration - a national primary drinking water regulation would 

help protect public health. 

Thank you. 

Amelia Kroeger 65 Stubbs Bay Road Maple Plain MN 55359 

Response: See response to comment code 6120. 

Commenter Name: Charlotte Morton 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1913 

EPA Comment ID: 20789 

EPA Comment Code: 6120 

 

Comment: To whom it may concern, 

I am writing to urge the regulation of Perchlorate in our drinking water. We should not have such 

chemicals in our water ignored. Please keep our water clean and safe. 

Sincerely, Charlotte Morton 

Response: See response to comment code 6120. 

Commenter Name: Lucy Margolis 

Commenter Organization: Educational Rights Advocates, Inc. 

EPA Document ID: EPA-HQ-OW-2008-0692-1914 

EPA Comment ID: 20790 

EPA Comment Code: 6120 

 

Comment: It is my understanding that the EPA has decided, as a preliminary decision, not to 

regulate perchlorate in drinking water. That being the case, I am writing to request that you reverse 

that decision. I REQUEST THAT YOU REGULATE PERCHLORATE IN DRINKING 

WATER. 

It is my understanding that perchlorate is harmful to people - e.g., that it can impair the thyroid 

gland. As a person who has taken Rx Synthroid daily for many years, I personally support regulation 

of perchlorate so that others won't have impaired thyroid function. 

It is my understanding that developing fetuses, infants and children with thyroid impairment may 

suffer mental retardation, loss of hearing and speech, or deficits in motor skills. As an educational 

advocate for families of children with disabilities, I support regulation of perchlorate in order to 

reduce the potential number of children with special needs in the future. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 827 of 1099

It is my understanding that perchlorate has been found in at least 395 sites in 37 states, including 153 

public water systems serving over 20 million people. That's a public health hazard that cannot be 

ignored. So, for these and other good and sufficient reasons, I REQUEST THAT YOU 

REGULATE PERCHLORATE IN DRINKING WATER. 

Thank you for your time and consideration. 

Regards, 

Lucy Margolis, President Educational Rights Advocates, Inc. 10430 SW 99 Street Miami, Florida 

33176 Phone (305) 279-8855 Fax (305) 279-4880 Cell (305) 588-3858 Lucyedu@aol.com 

Response: See response to comment code 6120. 

Commenter Name: Joshua Squire 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1917 

EPA Comment ID: 20791 

EPA Comment Code: 6120 

 

Comment: I am greatly concerned about our exposure to toxic chemicals, both for environmental 

and personal health issues. Limiting our exposure can greatly increase our life-long health. 

Everything from household cleaners to beauty products and now to our drinking water seem to be 

loaded with toxins. The American people sometimes rely on government agencies to help protect it's 

constituents. It seems to me that if the EPA did not regulate a known toxin in our drinking water, 

then they would not be doing the service that they were organized for in the first place. I urge the 

EPA to regulate Perchlorate in our drinking water. 

Thank you, Joshua Squire 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1918 

EPA Comment ID: 20792 

EPA Comment Code: 6120 

 

Comment: I am quite diturbed that the EPA is considering NOT regulating perchlorate in the 

environment. It is the EPAs duty and should be morally obligated to do what is right for the health 

of the environment and citizens. Do not be pressured by other governement agencies or 

corporations and do what you were founded to do. Please...Do not risk the health of the 

environment and it citizens. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 828 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-1922 

EPA Comment ID: 20794 

EPA Comment Code: 6120 

 

Comment: Please keep perchlorate out of my drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1923 

EPA Comment ID: 20795 

EPA Comment Code: 6120 

 

Comment: I am appalled by the EPA's decision to NOT regulate perchlorate in drinking water. 

This is an astounding position for the agency to take since perchlorate can cause significant human 

health problems, even at levels much lower than previously thought. We and our children have 

enough insults to our health and immune systems each day without the EPA making it worse by 

working for corporations instead of the public at large. The EPA violates its fiduciary responsibility 

to the citizens of this nation by refusing to regulate a known toxin. Please reverse this decision. 

Please make the people in the EPA do their jobs. Protecting the public from these kinds of 

contaminants is what the agency exists to do. If the EPA does not step in and do what they were 

created for, then possibly it is time to do away with the EPA and replace it with an agency that will 

do its job. 

Response: See response to comment code 6120. 

Commenter Name: Robert L. Darwin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1926 

EPA Comment ID: 20796 

EPA Comment Code: 6120 

 

Comment: The EPA should do whatever they can to keep Perchlorates out of our drinking water. 

 Robert L. Darwin Alexandria, VA 703-548-3595 

Response: See response to comment code 6120. 

Commenter Name: R. Perla 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1929 

EPA Comment ID: 20797 

EPA Comment Code: 6120 

 

Comment: Please keep harmful toxins like perchlorate out of our drinking water. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 829 of 1099

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1931 

EPA Comment ID: 20798 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1932 

EPA Comment ID: 20800 

EPA Comment Code: 6120 

 

Comment: Very simply, people shouldn't be forced to drink water that is toxic. Perchlorate in water 

can be measured. It's toxicity can be determined. Therefore limits on allowable amounts in drinking 

water can be drafted and enforced. Just do it! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1935 

EPA Comment ID: 20801 

EPA Comment Code: 6120 

 

Comment: Please reconsider regulating perchlorate in drinking water. The health risks warrant it. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1938 

EPA Comment ID: 20802 

EPA Comment Code: 6120 

 

Comment: You must develop an MCL for perchlorate, along with MTBE, TBA, and 1,4-dioxane, 

among others. It is totally irresponsible for EPA to cave to DOD, the petroleum industry and others 

and not protect the public. You work for US. 

Get a move on with doing your job! 

Response: Regarding regulating perchlorate in drinking water, see response to comment code 6120. 

Regarding regulating MTB, TBA and 1,4-dioxane, this is outside of the scope of this action. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 830 of 1099

Commenter Name: Yvonne Rost 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1946 

EPA Comment ID: 20803 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. I don't want my children 

exposed to the effects of this chemical, nor would I want any family or friends to be afflicted by it. 

Yvonne Rost Ferndale, MI 

Response: See response to comment code 6120. 

Commenter Name: J. Coleman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1948 

EPA Comment ID: 20804 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. It's difficult to believe that a 

"protection" agency would accept a chemical that has health impacts at lower levels than previously 

thought. We should have a national drinking water regulation to provide a meaningful opportunity 

to protect public health 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1954 

EPA Comment ID: 20805 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. When I learned that 

Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development and metabolism, I was baffled by the EPA's even considering not to regulate it. It's 

used in rocket fuel and explosives and is a very harmful chemical. It should not be in drinking water, 

but even the EPA has found it in 37 states, including 153 public water systems serving over 20 

million people. Some estimates are even higher. Not setting a regulation for percholate is not 

environmental protection. I urge you, once again, to reverse your preliminary determination. 

Response: See response to comment code 6120. 

Commenter Name: Jay Lees 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 831 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-1957 

EPA Comment ID: 20806 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water (Re: Document ID EPAHQ-OW-2008-0692-0001). Perchlorate contamination has health impacts at lower levels than 

previously thought by experts. Additionally, developing and instituting a national primary drinking 

water regulation would provide a meaningful opportunity to protect public health. Perchlorate, even 

in small amounts, can impair the thyroid gland, which controls growth, development and 

metabolism. Developing fetuses, infants and children with thyroid impairment may suffer mental 

retardation, loss of hearing and speech or deficits in motor skills. Our Governmental agencies 

should be in the business of passing regulations that help protect the health and livelihoods of all of 

the citizens of our great Country, and reversing the preliminary determination on Perchlorate 

contaminaltion levels in drinking water is one of many ways for a Government Agency to perform 

to its public charter. VR, Jay Lees, Lexington Park, Maryland. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1958 

EPA Comment ID: 20807 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

* Perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; * a national primary drinking water regulation would provide a meaningful 

opportunity to protect public health. 

This is COMPLETELY ridiculous! I cannot believe this is something that we have to be concerned 

about. In this country, in this time period, that I have to be worried about the water that I am 

drinking. You are the ENVIRONMENTAL PROTECTION AGENCY not the "let's make it easy 

for business to do whatever the hell they want" agency. PROTECT the environment and people! 

Honestly, what did you think you were supposed to be spending your time on when you applied at 

the EPA? 

I'm seriously disturbed and disappointed. 

Response: See response to comment code 6120. 

Commenter Name: 

Commenter Organization: The Night Move, LLC 

EPA Document ID: EPA-HQ-OW-2008-0692-1960 

EPA Comment ID: 20809 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 832 of 1099

 

Comment: Perchlorate contamination is a nationwide problem that can impact health at lower 

levels than previously thought. It is a dangerous chemical that affects the thyroid gland, potentially 

impairing the body's regulation of growth, development and metabolism. The EPA has found 

perchlorate in at least 153 public water systems. This chemical is used in rocket fuel and explosives. 

The companies creating these products with harmful side effects obviously aren't concerning 

themselves with the impact they are having on our environment. The government is allowing this. 

Ultimately, a regulation on the use of perchlorate would be the best answer to the health concerns of 

Americans. However, a national regulation of drinking water would also provide an opportunity to 

protect public health. Please, I urge the EPA to reverse its preliminary determination on setting a 

regulation for perchlorate in drinking water. 

 Thank you. 

The Night Move, LLC 

Response: See response to comment code 6120. 

Commenter Name: George Ferguson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1961 

EPA Comment ID: 20810 

EPA Comment Code: 6120 

 

Comment: We have enough problems with the water quality now, please do not allow more 

problems by not regulating percholate in our water. There has to be a way of controlling water 

pollution. 

Respectfully, George Ferguson 

Response: See response to comment code 6120. 

Commenter Name: Monica Juitt 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1963 

EPA Comment ID: 20811 

EPA Comment Code: 6120 

 

Comment: Dear Official, 

I am contacting you today to request the U.S. Environmental Protection Agency reconsider its 

preliminary determination to not set a regulation for perchlorate in drinking water. Perchlorate is a 

harmful chemical used in rocket fuel, flares, and explosives and even in small amounts can have very 

serious health impacts to our citizens. These include deficits in hearing, speech, motor skills and 

mental capacity. 

Please look at the facts and consider regulating perchlorate in our drinking water. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 833 of 1099

Thank you, 

Monica Juitt 

Response: See response to comment code 6120. 

Commenter Name: K. O'Sullivan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1965 

EPA Comment ID: 20812 

EPA Comment Code: 6120 

 

Comment: Please do everything necessary to keep perchlorate out of our nation's drinking water. 

Response: See response to comment code 6120. 

Commenter Name: J. Nash 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1966 

EPA Comment ID: 20813 

EPA Comment Code: 6120 

 

Comment: Your standards should be very tough regarding perchlorate and other contaminants in 

water. It is amazing to me that you would even consider removing perchlorate from your 

surveillance. This only reinforces what most already believe about Republicans, which is that you are 

in the service of one or another large business, not the public. Goodbye and good riddance in 

January! 

Response: See response to comment code 6120. 

Commenter Name: Ricarda G. Black 

Commenter Organization: Welcome to Wellness 

EPA Document ID: EPA-HQ-OW-2008-0692-1970 

EPA Comment ID: 20814 

EPA Comment Code: 6120 

 

Comment: Please reverse your decision not to regular perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: Barbara Sullivan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1976 

EPA Comment ID: 20815 

EPA Comment Code: 6120 

 

Comment: Dear Sirs, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 834 of 1099

I always ask government agencies what their charge is. So, I wish to ask you what is your charge? 

Perchlorate is dangerous to human health and should thus be regualated. Government is to do for 

people what they cannot do for themselves. It is a great responsibility and yet a privilege to protect 

the people of this great nation. Not to regulate dangerous pollutants in our drinkng water seems like 

you have forgotten why this agency exists. Please answer your conscience when making decisions 

that impact our children. 

Respectfull, Barbara Sullivan Citizen 2005 22nd Ave. NE Minneapolis, MN 55428 

Response: See response to comment code 6120. 

Commenter Name: Laurel 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1977 

EPA Comment ID: 20816 

EPA Comment Code: 6120 

 

Comment: please keep our drinling water safe, no perchlorate 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1978 

EPA Comment ID: 20817 

EPA Comment Code: 6120 

 

Comment: Please keep perchlorate out of drinking water, start regulating now. 

Response: See response to comment code 6120. 

Commenter Name: Dave Schaenzer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1979 

EPA Comment ID: 20818 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

I do not want to drink perchlorate contamination in my water. This is a nationwide problem and has 

health impacts. I suggest that having a national primary drinking water regulation would provide a 

uniform standard that would protect public health at a federal level. This would save the cost of 

State by State regulations. This would also prevent long litigative process thru the individual states. 

Thank You Dave Schaenzer 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 835 of 1099

Commenter Name: D. Nelson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1981 

EPA Comment ID: 20819 

EPA Comment Code: 6120 

 

Comment: Perchlorate must be regulated in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1983 

EPA Comment ID: 20822 

EPA Comment Code: 6120 

 

Comment: This chemical has been linked to thyroid problems in vulnerable populations of 

newborns, young children and pregnant women. The relaxation of this standard is harmful to public 

health. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1984 

EPA Comment ID: 20823 

EPA Comment Code: 6120 

 

Comment: I would like to know how this is in some way justified by President Bush?? This is 

drinking water for the very same infants that Mr. Bush and company supposedly try to "save" from 

abortion. I guess once they are out of the womb, these babies are no longer politically important and 

can be given poison. Where are all the right wing evangelicals that are so angry about abortion but 

never say a word in protest of infants being provided poisoned water by our government?? What a 

conscience you must have Mr. Bush!! It is no wonder why you have been selected as one of the 

worst president's of our life time - I would say the worst in our entire history as a country. 27% 

approval rating?? do you have any shame? and to make matters worse, at the last minute of the 

presidency when people think you can't go any lower; you push forward with these insane laws! 

Amazing how selfish you can be. The days till your last day in office cannot come soon enough! 

Hope all your buddies with deep pockets are able to talk to your creator when its time for final 

judgement! Because from where I'm standing; you definitely have a long list of sins to account for! 

Response: No response necessary, this is not a comment. 

Commenter Name: Jasmin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1985 

EPA Comment ID: 20824 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 836 of 1099

EPA Comment Code: 6120 

 

Comment: 11/06/08 

Dear EPA, 

I also do not want perchlorate in my drinking water. 

Jasmin 326 N. Royal St. Alex. VA 22134 

Response: See response to comment code 6120. 

Commenter Name: Ben Spriggs 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1986 

EPA Comment ID: 20825 

EPA Comment Code: 6120 

 

Comment: 11/06/08 

Dear EPA, 

Please cap perchlorate in my water resources. 

Ben Spriggs 312 N. Royal St. Alexandria, VA 22134 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1991 

EPA Comment ID: 20826 

EPA Comment Code: 6120 

 

Comment: Perchlorate needs to be reduced and or elimanted in the drinking water. This issue 

needs to be addressed and better regulated, not swept under the rug. This is a major health concern, 

and as a woman, mother and citizen of the USA, I am astounded that this issue with Perchlorate 

contaminating the water that I drink exist. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1992 

EPA Comment ID: 20827 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 837 of 1099

Comment: Pushing through this regulation is harmful to the general populous and should not be 

continued until an acceptable review period has been established. This kind of government 

regulatory process without adequate review and study is unacceptable and only panders to special 

interest. 

Response: EPA announced on October 10, 2008, its preliminary regulatory determination that a 

national primary drinking water regulation for perchlorate would not present "a meaningful 

opportunity for health risk reduction for persons served by public water systems." In response to 

requests from several stakeholders, EPA reopened the public comment period for an additional 15 

days. 

Commenter Name: T. Dginazio 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1993 

EPA Comment ID: 20828 

EPA Comment Code: 6120 

 

Comment: I am outraged by this last minute rule changing. Will phone White House Monday to 

protest under cutting the public trust. The maximum safe level for perchlorate in drinking water is 

now 15 times higher than what was declared safe in 2002. Under this new standard, more than 16 

million Americans are exposed to unsafe levels of perchlorate in their drinking water, and 

independent analysis shows anywhere from 20 to 40 million Americans at risk. Perchlorate has been 

found in the drinking water in 35 states in the U.S. This chemical has been linked to thyroid 

problems in vulnerable populations of newborns, young children and pregnant women. The 

relaxation of this standard is harmful to public health. outraged by this last minute rule changing. 

Response: See response to comment code 6120. 

Commenter Name: Aaron Peterson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1994 

EPA Comment ID: 20829 

EPA Comment Code: 6120 

 

Comment: It has been shown that perchlorate greatly impacts human health by interfering with 

iodide uptake into the thyroid gland. Its greatest impact is on newborns, young children, and 

pregnant women. While small amounts of perchlorate may not pose a serious threat, large amounts 

endanger human health and water resources. A lack of regulation for perchlorate leaves me 

concerned for the developmental health of those most vulnerable to the chemical's effects. 

-Aaron Peterson 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1995 

EPA Comment ID: 20830 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 838 of 1099

EPA Comment Code: 6120 

 

Comment: Enough chemicals in our drinking water. The evidence from reports on the EPA's page 

show that perchlorate is toxic and we should not be drinking water with it. It is even found in 

mother's milk. The government is the cause of the contamination and the study was done by 

industry. It is obvious that the EPA is not really protecting the citizens. Regulate perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1996 

EPA Comment ID: 20831 

EPA Comment Code: 6120 

 

Comment: Regulate perchlorate now! 

Response: See response to comment code 6120. 

Commenter Name: Mary Moore 

Commenter Organization: Lindon Park Neighborhood Association (LPNA) 

EPA Document ID: EPA-HQ-OW-2008-0692-2002 

EPA Comment ID: 20835 

EPA Comment Code: 6120 

 

Comment: EPA needs be moving toward the adoption of standards that protect the public from 

major health threats and not toward deregulation, especially when the primary exposure pathway for 

perchlorate is from contaminated drinking water. 

Perchlorate is extremely persistent. Lack of regulation will not diminish this health risk to the public. 

LPNA respectfully requests that EPA develop a legal standard for perchlorate in drinking water. 

Sincerely, 

Mary Moore Lindon Park Neighborhood Association Phoenix, AZ 

Response: See response to comment code 6120. 

Commenter Name: Andy 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2006 

EPA Comment ID: 20836 

EPA Comment Code: 6120 

 

Comment: Dear Sir or Madaam, 

I think clean water is a good idea. Please do all you can to make sure it is clean. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 839 of 1099

Thanks Andy 

Response: See response to comment code 6120. 

Commenter Name: Heather Mastroddi 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2008 

EPA Comment ID: 20838 

EPA Comment Code: 6120 

 

Comment: Water Docket ID # EPA-HQ-OW-2008-0692 

To Whom It May Concern, 

I would like to see more research on also regulating the harmful chemical perchlorate in our water. 

Thank you, 

Heather Mastroddi 601 Poplar St. Catasaqu, PA 18032 

Response: See response to comment code 6120. 

Commenter Name: Kimberly Scherman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2009 

EPA Comment ID: 20842 

EPA Comment Code: 6120 

 

Comment: Docket ID # EPA-HQ-OW-2008-0692 

To whom it may concern: 

Perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought. It can impair thyroid gland which controls growth, developmental health 

impairment. Please regulate this substance!!!! 

Sincerly, 

Kimberly Scherman 640 S. 14th St. Catasaqua, PA 18032 

Response: See response to comment code 6120. 

Commenter Name: Brenda Heininger 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2013 

EPA Comment ID: 20845 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 840 of 1099

Comment: I feel primary drinking water regulation is needed to protect public health. 

Perchlorate is a very harmful chemical which needs to be regulated. 

Brenda Heininger 2317 Silo Dr. Easton, PA 18040 

11/10/08 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2014 

EPA Comment ID: 20847 

EPA Comment Code: 6120 

 

Comment: What could the EPA possibly be thinking? PLEASE, PLEASE.....regulate this chemical 

in our drinking water!!!!! 

Response: See response to comment code 6120. 

Commenter Name: E. Cuffari 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2015 

EPA Comment ID: 20848 

EPA Comment Code: 6120 

 

Comment: Please reverse this decision on the regulation of Perchlorate in our drinking water. The 

last thing we need is Another chemical doing harm to US and our children. Since this chemical has 

been found in 37 states drinking water , I feel it's important to regulate. 

Response: See response to comment code 6120. 

Commenter Name: Lynn Thorp 

Commenter Organization: Clean Water Action 

EPA Document ID: EPA-HQ-OW-2008-0692-2017 

EPA Comment ID: 20850 

EPA Comment Code: 6120 

 

Comment: Clean Water Action has been concerned about perchlorate contamination for many 

years and has worked with communities facing perchlorate contamination of their water supplies 

and in several states where drinking water standards have been considered and/or set. Drinking 

water is a priority area for the organization and we work on many aspects of Safe Drinking Water 

Act implementation. 

Clean Water Action urges the Agency to reconsider its preliminary determination NOT to set a 

Maximum Contaminant Level (MCL) for perchlorate at this time. With tens of millions of drinking 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 841 of 1099

water consumers affected and given that perchlorate affects some of our most vulnerable people the 

most - infants and children - there is a meaningful opportunity for health risk reduction. 

Response: See response to comment code 6120. 

Commenter Name: Donna Wolsted 

Commenter Organization: Gleason Lake Improvement Association (GLIA) 

EPA Document ID: EPA-HQ-OW-2008-0692-2018 

EPA Comment ID: 20852 

EPA Comment Code: 6120 

 

Comment: We want to maintain the best drinking water we can. 

Please eliminate percholate from rocket fuels and explosives. 

We have to be aware that the cancer and other diseases in U.S. have some strong contributing 

factors that other countries do not have. 

I am not willing to risk my health on having more chemicals in our food or water. because the gov. 

"thinks" it is safe. Donna Wolsted, GLIA 

Response: See response to comment code 6120. 

Commenter Name: Lenny Siegel 

Commenter Organization: Center for Public Environmental Oversight 

EPA Document ID: EPA-HQ-OW-2008-0692-2019 

EPA Comment ID: 20856 

EPA Comment Code: 6120 

 

Comment: If EPA were serious about protecting the health of America’s children, it would move 

forward with plans to develop a legal standard for perchlorate in drinking water. In the course of 

that effort, it should consider how other contaminants might contribute to the problem. 

Finally, over the past decade, our understanding of the perchlorate threat has changed. Large sources 

of perchlorate pollution, associated with rocket-fuel production and other industrial activity, remain. 

However, it appears that perchlorate exposure is widespread at low levels also because of natural, 

agricultural, and incidental sources. To develop a public health strategy that addresses such 

exposures, we need a drinking water standard that requires the sampling of our water supplies at the 

low levels found to be a potential problem by the Centers for Disease Control. Even if it turns out 

that other factors-such as low iodine consumption-play a key role in the manifestation of thyroid 

dysfunction, such sampling is essential to protect the health of our children for decades to come. 

Sincerely, (submitted electronically) Lenny Siegel Executive Director 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 842 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-2022 

EPA Comment ID: 20857 

EPA Comment Code: 6120 

 

Comment: It doesn't take a rocket scientist to know that drinking rocket fuel is unhealthy. 

Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development and metabolism. Is there any question that Perchlorate in our water needs to be 

banned? 

Response: See response to comment code 6120. 

Commenter Name: Doug Bendele 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2025 

EPA Comment ID: 20858 

EPA Comment Code: 6120 

 

Comment: I urge the EPA to regulate perchlorate in drinking water. Perchlorate contamination has 

been found to be a nationwide problem with potentially devastating medical effects. Please exercise 

the authority given to you to protect my children and yours. 

Doug Bendele, human, father, husband, citizen, engineer 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2026 

EPA Comment ID: 20859 

EPA Comment Code: 6120 

 

Comment: NO perchlorate in my water please regulate, accountability good - clean water best. 

Response: See response to comment code 6120. 

Commenter Name: E.D. Levinson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2036 

EPA Comment ID: 20860 

EPA Comment Code: 6120 

 

Comment: It seems more than dangerous NOT to regulate perchlorate - please reconsider 

immediately. 

Thank you. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 843 of 1099

Commenter Name: Hannah Durocher 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2037 

EPA Comment ID: 20861 

EPA Comment Code: 6120 

 

Comment: As a member of the general public, I was horrified to hear that the EPA is considering 

NOT regulating perchlorate in drinking water. This chemical has been shown to be harmful to 

human and animal health. 

As someone with a thyroid problem who has seen the number of people with thyroid problems 

increase over the last few decades, I was appalled to learn that the EPA has made a preliminary 

decision to not regulate a substance that has been shown to damage the thyroid gland. 

In our time of bottled spring water for the wealthy, the failure to regulate perchlorate would 

disproportionately affect the health of the middle class and working poor. This is immoral and bad 

for health care costs. 

The purpose of the government is to serve the needs of the people--not the needs of industry 

without any consideration for the people. I urge the I urge the EPA to reverse its preliminary 

decision and make a stand for moral stewardship of our nation's drinking water. 

Hannah Durocher 1407 N. Kenilworth St. Apt. 3 Arlington, VA 22205 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2038 

EPA Comment ID: 20862 

EPA Comment Code: 6120 

 

Comment: Dear EPA: 

Please regulate the percholate in drinking water and protect public health. I understand the 

contaminant can have harmful affects at levels lower than thought previously. 

Thank you for your attention to this matter. 

Response: See response to comment code 6120. 

Commenter Name: M. King 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2041 

EPA Comment ID: 20863 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 844 of 1099

Comment: You must regulate Perchlerate in Drinking water, We do not know the possible effects 

that ingestion of this toxic chemical can cause. Start Regulating it Now! 

Response: See response to comment code 6120. 

Commenter Name: R. James 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2044 

EPA Comment ID: 20864 

EPA Comment Code: 6120 

 

Comment: Keep Perchlorate out of our Drinking Water. 

Response: See response to comment code 6120. 

Commenter Name: Gabriel Donovan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2046 

EPA Comment ID: 20865 

EPA Comment Code: 6120 

 

Comment: To the EPA, 

I write to petition for the regulation of Perchlorate in America's water resources. As with all 

chemical ingredients in use today, Perchlorate is a mystery. A mystery in that we do not know the 

long term ramifications of exposure in humans and to the environment. The preliminary findings 

point to ill effects in both regards. For this reason I strongly urge you to reconsider your position of 

non regulation. We the people of the United States depend on your vigilant watch to protect us 

from the danger of industrial pollutants. Regulate Perchlorate. 

Sincerely, 

Gabriel Donovan Texas 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2047 

EPA Comment ID: 20866 

EPA Comment Code: 6120 

 

Comment: Our healthcare system needs reform and Social Security is straining and will get worse. 

The health problems brought on by not regulating percolate can be prevented. It is irresponsible to 

ignore this element and deem it as harmful. 

Please reverse your decision. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 845 of 1099

Response: See response to comment code 6120. 

Commenter Name: Kathryn S Taylor 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2048 

EPA Comment ID: 20867 

EPA Comment Code: 6120 

 

Comment: Please, please, please reconsider this decision to allow perchlorate in our drinking water. 

We are facing enough cancer and other health issues because of chemicals in our water and soil. 

For health, Kathryn S Taylor 154 SE Lincoln Circle North St. Petersburg, FL 33703 

Response: See response to comment code 6120. 

Commenter Name: Della R. Post 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2053 

EPA Comment ID: 20868 

EPA Comment Code: 6120 

 

Comment: I am appealing to you in the interest of all citizens who drink water (everyone, including 

you) to reverse your decision not to regulate the amount of Perchlorate in our water supplies. Too 

many studies have found clear danger allowing this contaminent to remain in our water. To allow it 

to continue harming us is irresponsible behavior from an organization whose job is to protect the 

American people. 

Sincerely, Della R. Post 154 Village Circle Oakdale, PA 15071 

Response: See response to comment code 6120. 

Commenter Name: Justin White 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2058 

EPA Comment ID: 20869 

EPA Comment Code: 6120 

 

Comment: Can anyone come up with one good reason to put Perchlorate in the drinking water? 

Aside from the obvious one, which is that it is the cheapest, and sneakiest, way for a 

corporation/government to get rid of a dangerous byproduct. As was done with fluoride, a 

byproduct of aluminum smelting, and ammonium, which killed all of my fish and thus, can't be all 

that good for you. 

Adding Perchlorate to our drinking water is a ridiculous notion and everyone knows it. Wouldn't it 

be nice if people were truthful and responsible and took accountability for their actions? 

Concerned Citizen, Justin White 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 846 of 1099

Response: Perchlorate is not added to drinking water. There are three principal sources of the 

perchlorate in the environment: its use as an oxidizer (rocket propellants, fireworks, flares and 

explosives), its presence in Chilean nitrate fertilizer, and formation via atmospheric processes. 

Commenter Name: Margaret Tait 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2062 

EPA Comment ID: 20870 

EPA Comment Code: 6120 

 

Comment: I have lived with thyroid disease for 13 years. It makes every day harder and has effected 

every aspect of my health and life. Without regulation, sadly, industry does not often take the action 

needed to protect the public from contaminants. It makes no sense to accept any risk to our 

children's health. We must regulate perchlorate's presence in our water. 

Margaret Tait Brighton, Michigan 

Response: See response to comment code 6120. 

Commenter Name: Pamela Rogow 

Commenter Organization: Eco Impresario Services 

EPA Document ID: EPA-HQ-OW-2008-0692-2063 

EPA Comment ID: 20871 

EPA Comment Code: 6120 

 

Comment: News of the EPA's impending reversal of its initial determination to protect drinking 

water from perchlorate contamination is a great mistakes. Please protect the public from this danger. 

Response: See response to comment code 6120. 

Commenter Name: Susie Bryan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2065 

EPA Comment ID: 20872 

EPA Comment Code: 6120 

 

Comment: Please do not contaminate the water with one more chemical. We have a daughter 

affected with autism and is not able to detoxify herself very well due to low glutathione levels. This 

is common with children affected by autism. Whether or not the EPA finds that there is a safe 

amount that does not cause long-term affects on "people" doesn't speak to the large population of 

people that are having a hard time processing all the chemicals that are CURRENTLY out there. 

Please hear our voices and don't add any more chemicals to the water that do (in some part) have a 

toxicity level (even though they haven't shown to have a large effect). Any toxicity is a lot of toxicity 

for a child on the spectrum! 

Susie Bryan 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 847 of 1099

Response: Perchlorate is not added to drinking water. There are three principal sources of the 

perchlorate in the environment: its use as an oxidizer (rocket propellants, fireworks, flares and 

explosives), its presence in Chilean nitrate fertilizer, and formation via atmospheric processes. 

Commenter Name: J. and D. Dietz 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2066 

EPA Comment ID: 20873 

EPA Comment Code: 6120 

 

Comment: Pls. do not allow rocket fuel to remain in our water. You may say it is not harmful but 

what is causing our sicknesses and cancers? Water should be clean and have no man made or natural 

substances in it which could cause harm. Who knows what we will find out in the future concerning 

our digesting rocket fuel. This is preposterous!! Filter it out of our water! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2068 

EPA Comment ID: 20874 

EPA Comment Code: 6120 

 

Comment: We need cleaner water. Please protect us from chemicals like perchlorate! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2069 

EPA Comment ID: 20875 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Donna Levin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2070 

EPA Comment ID: 20876 

EPA Comment Code: 6120 

 

Comment: Please change your decision on percholate, and regulate its presence in drinking water. 

We depend on you. Thank you. 

Donna Levin Elkins Park, Pennsylvania 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 848 of 1099

Response: See response to comment code 6120. 

Commenter Name: Susan S. Merrill 

Commenter Organization: Clean Water Action 

EPA Document ID: EPA-HQ-OW-2008-0692-2073 

EPA Comment ID: 20877 

EPA Comment Code: 6120 

 

Comment: Greetings: 

Please reverse the deregulation of perchlorate, a chemical found in rocket fuel, from drinking water 

in the United States. Americans need clean drinking water and should be protected from 

contaminants in it such as perchlorate. 

Thank you for making this change in the law. 

Sincerely, 

Susan S. Merrill Member, Clean Water Action 

Response: See response to comment code 6120. 

Commenter Name: Caryn Mandelbaum 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2076 

EPA Comment ID: 20878 

EPA Comment Code: 6120 

 

Comment: Why bother having an EPA when it is unwilling to carry out its purpose-- to secure 

clean water (all water), air and land? Specifically, by denying its responsibility to regulate perchlorate 

in drinking water, the EPA is offending the leaders that chartered the institution and all people 

affected by its irresponsibility. 

Perchlorate contamination is a problem nationwide. A small amount of this pernicious chemical 

poses a massive threat to our freshwater resources-- groundwater. There are communities, like some 

near me in California, that are nearly entirely dependent on groundwater. They can only expect to 

suffer grave health impacts from drinking perchlorate-laden groundwater. All the EPA has done 

here is to declare a Superfund site. That is unacceptable. 

The EPA was created in order to be responsible for the government and government-sanctioned 

industrial pollution to our natural resources. Perchlorate found its way into our drinking water 

supply as a result of the Department of Defenses contracts with the aerospace industry. It sounds 

like paranoia, but I know the industry's and government's protective measures or accountability 

could not be further from the truth. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 849 of 1099

If you are not going to stand up to your responsibility, stop wasting my tax dollars and get out of a 

regulatory regime. If you are going to continue to pretend to be the department that secures clean 

water, air and land, then set perchlorate standards and clean-up superfund sites. 

By all means, I expect a response-- both national and personal. 

Sincerely, Caryn Mandelbaum, carynm5@gmail.com 

Response: Regarding regulating perchlorate, see response to comment code 6120. Regarding 

cleaning up Superfund sites, see response to comment code 6300. 

Commenter Name: Theresa Quigley-Uhl 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2077 

EPA Comment ID: 20879 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. Please keep our water free 

from harmful chemicals. Keep our children healthy. 

Thank you, Theresa Quigley-Uhl 1134 Snyder avenue philadelphia,PA 19148 

tajuhl7@aol.com 

Response: See response to comment code 6120. 

Commenter Name: Robin Porter 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2078 

EPA Comment ID: 20880 

EPA Comment Code: 6120 

 

Comment: I urge the EPA to reconsider its regulation of perchlorate in our drinking water. This 

chemical can cause serious health issues in developing fetuses and children, and it's long-term effects 

are not known. We shouldn't risk the lives of our children to find out! Please keep our drinking 

water clean, safe and free of harmful chemicals such as perchlorate. 

Thank you, Robin Porter Concerned citizen 

Response: See response to comment code 6120. 

Commenter Name: Michael Doxy 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2079 

EPA Comment ID: 20881 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 850 of 1099

Comment: 11/5 

To Whom it May Conern 

I would like to support the Clean Water Action Committees efforts to rid our local water supply of 

perchlorates. 

Michael Doxy 706 S. Royal St Alexandria, VA 22314 

Response: See response to comment code 6120. 

Commenter Name: Teresa Jordan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2080 

EPA Comment ID: 20882 

EPA Comment Code: 6120 

 

Comment: 3152 Shad Court Simi Valley, CA 93063 November 26, 2008 

Water Docket US EPA Mailcode: 2822T 1200 Pennsylvania Avenue, N.W. Washington, DC 20460 

 Re: DOCKET ID No. EPA-HQ-OW-2008-0692 (Preliminary Regulatory Determination on 

Perchlorate--Reopening of Public Comment Period (November 28, 2008 Deadline)). 

Dear Mr. Grumbles, and Mr. Burneson: 

I just read through the Santa Susana Field Laboratory's Perchlorate Work Plan, the State Water 

Resources Control Board's Proposed Recycled Water Policy Staff Report, and after mulling through 

my recent letters addressing the State Water Resources Control Board's proposed review of 

California's Anti-Degradation Policy (Resolution 68-16), I am convinced more than ever that it is of 

the utmost importance the USBPA initiates development of a national regulation for perchlorate in 

drinking water ASAP because if the types of decisions on water quality issues made by California's 

State and Regional Water Quality Control Boards are indicative of trends in the other 49 States such 

state of affairs significantly impact Americans nationwide. 

Sincerely, Mrs. Teresa Jordan 

Enclosures: 

November 19, 2008, Letter to the State Water Resources Control Board; Anti- degradation Policy. (3 

Pages) [See PDF Docket ID EPA-HQ-OW-2008-0692-2080] 

November 20, 2008, Letter to the State Water Resources Control Board; Anti- degradation Policy. (5 

Pages) [See PDF Docket ID EPA-HQ-OW-2008-0692-2080] 

Response: See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #8 - Food and Water Watch 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 851 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-1805 

EPA Comment ID: 20883 

EPA Comment Code: 6120 

 

Comment: Dear Administrator Johnson, 

I am writing to urge you to reconsider EPA's preliminary determination not to regulate perchlorate 

in drinking water. 

Perchlorate has been found in the drinking water supply of 35 states and the District of Columbia. 

Widespread human exposure to perchlorate was confirmed by the Center for Disease Control’s 

NHANES study, which found that 100 percent of the 2,820 randomly selected study participants 

had detectable levels of perchlorate in their urine. 

The widespread exposure of the population to some level of perchlorate raises serious health 

concerns. Perchlorate can inhibit the thyroid gland’s iodine uptake, potentially leading to 

hypothyroidism. Severe hypothyroidism during pregnancy can lead to abnormal fetal cognitive 

development, and even mild hypothyroidism during pregnancy is associated with subtle cognitive 

defects in children. Thus, perchlorate could alter fetal brain development, having lifelong cognitive 

effects for those affected. 

EPA’s failure to regulate perchlorate in drinking water places consumers - especially children and 

pregnant women - at risk. 

In response to this misguided determination, EPA’s own Children’s Health Protection Advisory 

Committee has drafted a letter expressing its concern with EPA’s decision not to regulate 

perchlorate. Members of the committee claim that EPA rushed a decision on perchlorate without 

taking time to consider all the latest peer-reviewed studies. 

Given the vital importance of fetal central nervous development not only for long-term health and 

development of children, but also for the viability of fetuses, why would EPA rush to a decision? 

Unfortunately, the only conclusion we can draw is that EPA has issued this determination to avoid 

strapping the Department of Defense with costs to clean up near military bases, missile testing sites 

and chemical plants. While millions of consumers’ health is jeopardized, it seems the budget 

concerns of the Pentagon or White House are driving EPA’s decision. 

This determination is clearly another instance of a regulatory agency shirking its responsibility to 

protect the American public. Instead of fulfilling its obligations under the SDWA, EPA has once 

again folded to pressure. 

Response: See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #6 - Earth Justice 

EPA Document ID: EPA-HQ-OW-2008-0692-0972 

EPA Comment ID: 20884 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 852 of 1099

Comment: Administrator Stephen L. Johnson 1101A EPA Headquarters 1200 Pennsylvania 

Avenue, NW, Ariel Rios Building Washington, DC 20460 

Subject: Protect Our Drinking Water From Perchlorate Contamination 

 Dear Administrator Johnson, 

I am writing to urge you reverse EPA's preliminary regulatory determination and set a protective 

drinking water standard for perchlorate as required by the Safe Drinking Water Act. 

Perchlorate contamination in our food and water supplies is too widespread, and its toxic effects too 

well known, for continued inaction on this problem. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1799 

EPA Comment ID: 20887 

EPA Comment Code: 6120 

 

Comment: I cannot believe that this is something that is even being debated. The idea of allowing 

an ingredient that is in rocket fuel to even be present in any percentage in our drinking water is 

utterly ridiculous. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1884 

EPA Comment ID: 20888 

EPA Comment Code: 6120 

 

Comment: This is crazy. Why would this administration go against the SCIENCE of this action? 

Are you trying to scheme your way into making the public FEAR tap water in order to boost the 

sales of bottled water by your best friends and corporate companies while putting the public health 

at risk? Wow, so there is actually movements being created around the support of tap water and 

against corporate giants. You're afraid of the people getting this right. Do the right thing in your last 

days in office. I really fear for the world you are leaving your children. Does that EVER cross your 

mind? Greed never solved any problems in our country. Grow up. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1891 

EPA Comment ID: 20889 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 853 of 1099

 

Comment: For Bush to pass something as absurd as this is pretty low of him. I would expect this 

out of a Republican, however. Most Republicans are only out for themselves or others who can 

provide top dollar. Perchlorate keep increasing in the drinking water. What will happen when they 

increas again? Will there be another determination of how safe the water is? Will the water still be 

declared 'safe'? I bet that if Bush and the rest of his administration had to drink the water, they 

would not pass such a thing. When will there be anyone in any sort of political office/setting who 

will care about the average American? Congress and the rest of capital know this, I am sure, but if 

the average American were to stand up and not take any of the [expletive] that was being fed to us, 

the people would actually be able to take charge of this country like it should be. The United States 

is becoming a [expletive] due to things (this docket) like this, and is alos why China is the next 'Land 

of Opportunity'. The U.S.A. is now the 'Land of Degregation and No Hope'. 

Thanks for the terrible job everyone on Capital Hill. I hope you enjoy destroying this once great 

country. 

Response: No response necessary, this is not a comment. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1921 

EPA Comment ID: 20890 

EPA Comment Code: 6120 

 

Comment: Someone better change the regulations on what is acceptable. 0% There is enough crap 

in the drinking water that EPA say is acceptable. Is it acceptable to POISON us? Let's regulate 

something that matters. I don't care if it's PPM or PPB the perchlorate levels are still unacceptable. 

Response: See response to comment code 6120. 

Commenter Name: D'Lanie Blaze 

Commenter Organization: TheAeroSpace 

EPA Document ID: EPA-HQ-OW-2008-0692-0641 

EPA Comment ID: 20891 

EPA Comment Code: 6120 

 

Comment: To Whom It May Concern: 

I am very concerned that the EPA is poised to walk away from monitoring perchlorate in our 

drinking water. Given the documented risk this contaminant poses to public health, this decision 

contradicts the purpose for which this agency was designed. 

Southern California's main industries during the 1950's and 1960's were atomic energy and 

aerospace. Santa Susana Field Laboratory (SSFL) was home to over 30,000 rocket engine tests and 

the worst nuclear accident in US history. During the Cold War and Space Race, the Atomic Energy 

Commission (AEC) and Department of Energy (DOE) encouraged rampant environmental 

pollution in the name of production and experimentation, resulting in massive contamination to 

ground and surface water. Presently, SSFL languishes in a state of contamination. Perchlorate 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 854 of 1099

remains a concern within our community; it has repeatedly tested beyond "safe" levels in drinking 

water, and thyroid issues are staggering in the neighborhoods surrounding SSFL. This is a 

nationwide concern, especially in communities that border military bases with a history of missile 

development. 

The DOE continues to evade accountability for environmental crimes, which spanned decades. The 

EPA's cavalier approach to public safety regarding perchlorate sets a dangerous precedent. 

Predictably, the public has been inadequately informed and provided with little time to offer 

educated comment before the opportunity to take part in the decision-making process expires. The 

EPA's attempt to rush this decision before administrative change - and while meeting only the 

minimum requirements for public participation (which are inept at best) - is very telling. The 

decision to cease monitoring for perchlorate in drinking water likely augurs trouble on the horizon 

for our citizens, the majority of which blindly trust agencies like the EPA to fulfill their 

responsibilities in an ethical, if not logical, fashion. 

Sadly, the opportunity to access information and become involved in decisions like this one are 

difficult. Conversely, the public is bombarded with pharmaceutical ads which announce the 

availability of a wide variety of medication which is arguably necessary as a result of our routine 

exposure to a variety of toxins and pathways. Thyroid issues are steadily rising, and yet the 

government body tasked with this issue is willing to walk away from it. This does nothing but give 

rise to the possibility of collusion between EPA and pharmaceutical corporations. What is the payoff for walking away from perchlorate? This is certainly not a decision motivated by commitment to 

public safety. 

Response: See response to comment code 6120. 

Commenter Name: Brie Brigham 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1436 

EPA Comment ID: 20893 

EPA Comment Code: 6120 

 

Comment: Brie Brigham 118 South Gill Street State College, PA 16801 October 29, 2008 

Office of Ground Water and Drinking Water (4601) Ariel Rios Building 1200 Pennsylvania Avenue, 

NW Washington, DC 20460-0003 

To Whom It May Concern, 

I support the EPA's decision to regulate the concentration in drinking water, but believe the 

perchlorate contamination level considered safe should be lowered. Perchlorate occurs both 

naturally and through manufacturing, and is found in rocket fuel, fireworks, and airbags. Perchlorate 

enters United States drinking water from improper disposal by test sites, military bases, and chemical 

plants. A 2005 report by the EPA stated that the chemical compound polluted soil, groundwater, 

and drinking water in 35 states and has contaminated 153 public water systems in 26 states. The 

report also estimated that 16.6 million Americans are exposed to perchlorate at levels scientists 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 855 of 1099

consider unsafe. Perchlorate contamination in drinking water can have devastating effects, 

particularly on fetuses, newborns, and children. 

Response: See umbrella response under 6120. 

Commenter Name: Brie Brigham 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1436 

EPA Comment ID: 20896 

EPA Comment Code: 6120 

 

Comment: In conclusion, I applaud the EPA's decision to regulate perchlorate concentrations in 

drinking water. However, I believe the contamination level should be lowered so that fetuses, 

newborns, and children are not exposed to levels that are unsafe. 

Sincerely, Brie Brigham 

Response: Please see the response to comment code 6120. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20898 

EPA Comment Code: 6120 

 

Comment: EPA’s Preliminary Regulatory Determination on Perchlorate is an embarrassment to the 

agency. It marks the next step in a long journey away from sound science, impartiality, and public 

health protection towards biased decisions where the agency no longer even attempts to hide its 

partiality towards industry interests. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20902 

EPA Comment Code: 6120 

 

Comment: The combined effect of these multiple layers of corruption has been to make 

perchlorate look safe when it is not, and to make EPA appear as though it is simply servicing 

perchlorate polluters, which it is. The agency’s proposed action is nothing less than pandering to 

perchlorate polluters who would be made to clean up the tap water of 40 million people in 27 states 

if the agency were to conduct an honest assessment of the human health risks of perchlorate. 

This assessment makes a mockery of everything EPA stands for. It must not be adopted. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 856 of 1099

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20908 

EPA Comment Code: 6120 

 

Comment: The scientific evidence clearly points to the need for EPA to set a health protective 

drinking water standard for perchlorate - that is, a standard lower than the level shown to be 

associated with altered thyroid hormone levels in American women with low iodine intake. 

Unfortunately, EPA has relied on questionable science, an even more questionable computer model, 

and circular logic to justify its proposal to not regulate this harmful contaminant at all in our nation’s 

drinking water. This is inexcusable. 

EWG urges EPA to overhaul its poorly crafted assessment according to the points described in 

detail below and to live up to its mandate of protecting public health by setting a stringent drinking 

water standard for perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20917 

EPA Comment Code: 6120 

 

Comment: Conclusion 

As outlined above, EPA’s preliminary regulatory determination on perchlorate is rife with errors, 

omissions, and wrong assumptions. EPA relies on a computer model that was generated using the 

now discredited Greer study. In addition, EPA chooses to ignore the valuable data from human 

studies like the Blount study that show potential health risks to millions of U.S. residents from 

perchlorate exposures much lower that the proposed HRL of 15 ppb. EPA also disregards the 

vulnerability of breast fed infants and young children, in whom current perchlorate exposures could 

potentially result in decreases in thyroid hormone levels that have long-term adverse effects on brain 

development and growth. Perhaps most egregious is EPA’s finding that protecting 30,000 

pregnancies annually is not a sufficient reason to regulate this dangerous contaminant in drinking 

water. 

Response: See response to comment code 6120. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1432 

EPA Comment ID: 20919 

EPA Comment Code: 6120 

 

Comment: In the meantime, EWG calls on EPA to fix the numerous glaring errors in its 

assessment and to quickly move to set a health protective drinking water standard for perchlorate. 
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Sincerely, 

Dr. Anila Jacob, MD, MPH Senior Scientist Environmental Working Group 

References: 

Amitai Y, Winston G, Sack J, Wasser J, Lewis M, Blount BC, Valentin-Blasini L, Fisher N, Israeli A, 

Leventhal A. 2007. Gestational Exposure to High Perchlorate Concentrations in Drinking Water 

and Neonatal Thyroxine Levels. Thyriod 17(9): 843-50. 

Blount BC, Valentin-Blasini L, Osterloh JD, Mauldin JP, Pirkle JL. 2006a. Perchlorate Exposure of 

the US population, 2001-2002. Journal of Exposure Science and Environmental Epidemiology 

17(4): 400-07. 

Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell LK. 2006b. Urinary Perchlorate and 

Thyroid Hormone Levels in Adolescent and Adult Men and Women living in the United States. 

Environmental Health Perspectives 114(12): 1865-71. 

Dasgupta PK, Kirk AB, Dyke JB, Ochira S. 2008. Intake of Iodine and Perchlorate and Excretion in 

Human Milk. Environmental Science and Technology. 9/17/2008: epub ahead of print. 

EPA. 2008. Drinking water: Preliminary Regulatory Determination on Perchlorate. 

http://www.epa.gov/safewater/ccl/reg_determine2.html#perchlorate 

EWG. 2006. Thyroid Threat. http://www.ewg.org/reports/thyroidthreat 

EWG. 2008. FDA Food Testing Shows Widespread Rocket Fuel Contamination of Commonly 

Consumed Foods and Beverages. www.ewg.org/node/25875 

GAO. Testimony before the Subcommittee on Investigations and Oversight, Committee on Science 

and Technology, House of Representatives: Chemical assessments. 

www.gao.gov/new.items/d08810t.pdf 

Greer MA, Goodman G, Pleuss RC, Greer SE. 2002. Health Effect Assessment for Environmental 

Perchlorate Contamination: the Dose Response for Inhibition of Thyroidal Radioiodide Uptake in 

Humans. Environmental Health Perspectives (110): 927-37. 

Kirk AB, Martinelango PK, Tian K, Dutta A, Smith EE, Dasgupta PK. 2005. Perchlorate and iodide 

in dairy and breast milk. Environmental Science and Technology 39(7) 2011- 17. 

Kirk AB, Dyke JV, Martin CF, Dasgupta PK. 2007. Temporal patterns in Perchlorate, thiocyanate, 

and Iodide Excretion in Human Milk. Environmental Health Perspectives 115(2) 182-86. 

MassDEP. 2006. Update to "Perchlorate Toxicological Profile and Health Assessment". 

http://www.mass.gov/portal/gog_cache.jsp?q=cache:DvvnPHJtRYwJ:www.mass.gov/dep 

/toxics/perchlorate-toxicity-061206.pdf+Greer&access=p&output=xml_no_dtd&ie=UTF8&client=mgov&site=EOEAxDEPx&proxystylesheet=mgov&oe=UTF-8 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Murray WM, Egan SR, Kim H, Beru N, Bolger PM. 2008. US Food and Drug Administration's 

Total Diet Study: Dietary Intake of Perchlorate and Iodine. Journal of Exposure Science and 

Environmental Epidemiology 2008 (1-10)Epub ahead of print. 

Pearce EN, Leung AM, Blount BC, Bazrafshan HR, He X, Valentin-Blasini L, Braverman LE. 2007. 

Breast Milk Iodine and Perchlorate concentrations in Lactating Boston Area Women. Journal of 

Clinical Endocrinology and Metabolism 92(5):1673-7 

Response: See response to comment code 6120. 

Commenter Name: Lucy Allen 

Commenter Organization: Pacific Institute 

EPA Document ID: EPA-HQ-OW-2008-0692-1770 

EPA Comment ID: 20925 

EPA Comment Code: 6120 

 

Comment: November 5, 2008 

Administrator Stephen L. Johnson Water Docket, Environmental Protection Agency 2822T, 1200 

Pennsylvania Ave., NW Washington, D.C. 20460 

RE: Drinking Water: Preliminary Regulatory Determination on Perchlorate, Federal Register 

October 10, 2008, (73 FR 60262) (FRL-8727-6) Docket Number: EPA-HQ- OW-2008-0692 

Dear Mr. Stephen Johnson, 

The Pacific Institute would like to formally submit the following comments on the Environmental 

Protection Agency’s (EPA) Drinking Water Preliminary Regulatory Determination on Perchlorate. 

After reviewing the Preliminary Determination and relevant literature, we do not agree with the 

EPA’s determination that regulating perchlorate presents no "meaningful opportunity for health risk 

reduction for persons served by public water systems." While we recognize that the science upon 

which the determination is based has been contested, our comments address a number of further 

concerns, including the protection of vulnerable populations; the impacts that the determination will 

have on remediation efforts and future monitoring; and the criteria for what is considered to be a 

"meaningful opportunity" for protection of public health. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Lucy Allen 

Commenter Organization: Pacific Institute 

EPA Document ID: EPA-HQ-OW-2008-0692-1770 

EPA Comment ID: 20928 

EPA Comment Code: 6120 

 

Comment: Ongoing monitoring of drinking water is needed to safeguard public health. The EPA’s 

preliminary decision to not regulate perchlorate was contingent on the fact that a relatively small 

number of public water systems currently contain levels of perchlorate at unsafe levels. While this 
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may be true today, it may change, as perchlorate is widely used and easily leached. With uncertainties 

surrounding the extent of current contamination, and continued use of perchlorate,[FN11: Both 

Trumpolt et al. and Aziz et al. identify uncertainties in how current uses of perchlorate, e.g. in road 

flares and fireworks affect groundwater perchlorate levels. See footnotes 12,13.] the EPA should set 

a Primary Drinking Water Regulation to make ongoing monitoring mandatory. 

According to GAO 2007, federal and state agencies have found perchlorate in groundwater, surface 

water, soil, or public drinking water systems at almost 400 sites in 37 states, in concentrations 

ranging from 4 ppb to more than 3.7 million ppb. The GAO contends that "it is difficult to 

determine the extent of perchlorate in the United States or the status of any cleanup actions because 

EPA does not centrally track or monitor perchlorate detections, environmental releases, or cleanup 

activities." 

Many potential sources of perchlorate contamination in the U.S. exist, including munitions 

manufacture and disposal, use of explosives in rock blasting, manufacture and use of fireworks, 

manufacture and use of safety flares, and use of Chilean nitrate fertilizers.[FN12: Trumpolt, C., M. 

Crain, G. Cullison, S. Flanagan, L. Siegel, and S. Lathrop. (2005). Perchlorate: Sources, Uses, and 

Occurrences in the Environment. Retrieved Oct 27, 2008 from 

http://yosemite.epa.gov/r10/CLEANUP.NSF/PH/Arkema+Technical+Documents/$FILE/Perc 

hlorate-Sources-Occurance-In-The-Environment.pdf.],[FN13: Aziz, C., R. Borch, P. Nicholson, and 

E. Cox. (2006). Alternative Causes of Wide-Spread, Low Concentration Perchlorate Impacts to 

Groundwater. GeoSyntec Consultants, Guelph, ON, Canada. Retrieved Oct 27, 2008 from 

http://www.springerlink.com/content/p8m017624280752w/.] In addition to these ongoing uses of 

perchlorate, there may be environmental contamination from historic releases, for example from 

manufacture and disposal. This widespread use is likely to lead to further water contamination, as 

perchlorate is readily leached from soil into groundwater due to its high solubility and persistence in 

the environment. 

Response: See response to comment code 6120. 

Commenter Name: Lucy Allen 

Commenter Organization: Pacific Institute 

EPA Document ID: EPA-HQ-OW-2008-0692-1770 

EPA Comment ID: 20929 

EPA Comment Code: 6120 

 

Comment: The EPA determined that regulating perchlorate in drinking water does not pose a 

meaningful opportunity to protect public health-even as its report recognizes that 900,000 people 

will remain exposed to perchlorate at levels that could exceed the health reference level, up to 30,000 

of which are pregnant women at any given time. Protecting the health of these individuals, even if it 

is a small group, is significant, and the federal government has the capacity and responsibility to do 

so. 

Response: See response to comment code 6120. 

Commenter Name: Ron Curry 

Commenter Organization: New Mexico Environment Department 

EPA Document ID: EPA-HQ-OW-2008-0692-1796 
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EPA Comment ID: 20931 

EPA Comment Code: 6120 

 

Comment: In its preliminary determination, EPA has tentatively decided not to promulgate 

maximum contaminant levels (MCL's) for perchlorate under the federal Safe Drinking Water Act 

(SDWA), 42 U.S.C. [sections] 300f to 300j-26. The Environment Department strongly urges EPA to 

reconsider this preliminary determination and to promulgate an MCL for perchlorate at a level that 

will protect human health, including the health of subgroups at greater risk of adverse health effects. 

Response: See response to comment code 6120. 

Commenter Name: Caroline Baier-Anderson, PhD 

Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20941 

EPA Comment Code: 6120 

 

Comment: Comments from Environmental Defense Fund on the Preliminary Regulatory 

Determination on Perchlorate Docket EPA-HQ-OW-2008-0692 Federal Register / Vol. 73, No. 

198 / Friday, October 10, 2008 

Prepared by Caroline Baier-Anderson, Ph.D. Senior Health Scientist 

Submitted to Docket: November 28, 2008 

On behalf of Environmental Defense Fund, a non-profit, non-partisan, non- governmental 

environmental organization that combines law, policy, science and economics to find solutions to 

today's most pressing environmental problems, we offer the following comments on the Preliminary 

Regulatory Determination on Perchlorate. 

Environmental Defense Fund would like to express our strong disagreement with the 

Environmental Protection Agency's (EPA) Preliminary Regulatory Determination on Perchlorate, as 

presented in the Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008. EPA has 

determined that a national primary drinking water regulation for perchlorate would not present a 

meaningful opportunity for health risk reduction. We believe that this decision is predicated on a 

flawed reference dose, and the incorrect application of a physiologically based pharmacokinetic 

model, leading to the derivation of a faulty health reference level. Below we lay out the details of our 

criticism, and offer alternative views that justify promulgation of a stronger standard for perchlorate. 

Response: Regarding promulgating a perchlorate standard, see response to comment code 6120. 

Regarding the perchlorate reference dose, see response to comment 28863 under comment code 

2110; regarding application of the PBPK model, see responses to comment codes 2400 and 2410; 

and regarding derivation of the health reference level, EPA derived potential alternative HRLs for 14 

life stages (age groups) using the RfD and life stage-specific exposure information in the August 9, 

2009, notice (74 FR 41883; USEPA 2009b). These levels range from 1 μg/L to 47 μg/L and are the 

concentrations of perchlorate in drinking water that may result in total perchlorate exposures (from 

food and water) greater than the RfD for individuals at each life stage. These HRLs are calculated 

based on individuals who consume an average amount of perchlorate from food (except for 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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pregnant women where EPA used a 90th percentile dietary intake estimate), but who consume equal 

or more water on a per body weight basis than 90 percent of their cohorts. 

Commenter Name: Caroline Baier-Anderson, PhD 

Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20954 

EPA Comment Code: 6120 

 

Comment: EPA Can Reduce Health Risk by Promulgating a Perchlorate Standard 

In summary EPA has an opportunity to significantly reduce risks to human health by promulgating a 

perchlorate standard, providing that the reference dose is based on CDC data, taking into 

consideration sensitive subpopulations, including women of child-bearing age that are not receiving 

sufficient iodine, and the fact that hypothyroidism in the US is not only prevalent, but underdiagnosed and under-treated. All else follows from this initial calculation, as a reference dose based 

on the appropriate consideration of these factors will result in a more realistic estimate of the 

number of US citizens potentially impacted by perchlorate in drinking water. Such an analysis, based 

on more realistic assumptions, and newer, more accurate data, will provide concrete support for 

EPA action. 

References 

Andersen S, Pedersen KM, Bruun NH, Laurberg P. 2002. Narrow individual variations in serum T4 

and T3 in normal subjects: a clue to the understanding of subclinical thyroid disease. J Clin 

Endocrinol Metab 87:1068-1072. 

Aoki Y, Belin RM, Clickner R, Jeffries R, Phillips L, Mahaffey KR. 2007. Serum TSH and total T4 in 

the United States population and their association with participant characteristics: National Health 

and Nutrition Examination Survey (NHANES 1999-2002). Thyroid 17:1211-1223. 

Blount BK, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell KL. 2006. Urinary perchlorate and 

thyroid hormone levels in adolescent and adult men and women living in the United States. Environ 

Health Perspect 115:1865-1871. 

Blount BC, Valentin-Blasini L, Osterloh JD, Mauldin JP, Pirkle JL. 2007. Perchlorate exposure of 

the US Population, 2001-2002. J Expo Sci Environ Epidemiol 17(4):400-7. 

Caldwell KL, Jones R, Hollowell JG. 2005. Urinary iodine concentration: United States National 

Health And Nutrition Examination Survey 2001-2002. Thyroid 15:692-699. 

Crump KS, Gibbs JP. 2005. Benchmark calculations for perchlorate from three human cohorts. 

Environ Health Perspect 113(8):1001-8. 

Dasgupta PK, Kirk AB, Dyke JV, Ohira S-I. 2008. Intake of Iodine and Perchlorate and Excretion 

in Human Milk. Environ Sci Technol 42: 8115 - 8121. 
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Greer MA, Goodman G, Pleus RC, Greer SE. 2002. Health effects assessment for environmental 

perchlorate contamination: the dose response for inhibition of thyroidal radioiodine uptake in 

humans. Environ Health Perspect 110:927-937. 

Haddow JE, Palomaki GE, Allan WC, Williams JR, Knight GJ, Gagnon J, et al. 1999. Maternal 

thyroid deficiency during pregnancy and subsequent neuropsychological development of the child. 

N Engl J Med 341:549-555. 

Kirk AB, Martinelango PK, Tian K, Dutta A, Smith EE, Dasgupta PK. 2005. Perchlorate and iodide 

in dairy and breast milk. Environ Sci Technol 39:2011-2017. 

Kirk AB, Dyke JV, Martin CF, Dasgupta PK. 2007. Temporal patterns in perchlorate, thiocyanate 

and iodide excretion in human milk. Environ Health Perspect 115:182-186. 

Kohrle J. 2008. Environment and endocrinology: the case of thyroidology. Ann Endocrinol (Paris) 

69(2):116-22. 

Mage DT, Allen RH, Gondy G., Smith W., Barr D.B., and Needham L.L. 2004. Estimating pesticide 

dose from urinary pesticide concentration data by creatinine correction in the Third National Health 

and Nutrition Examination Survey (NHANES-III). J Expo Anal Environ Epidemiol 14:457-465. 

Morreale de Escobar G, Obregon MJ, Escobar del Rey F. 2000. Is neuropsychological development 

related to maternal hypothyroidism or to maternal hypothyroxinemia? J Clin Endocrinol Metab 

85:3975-3987. 

Pirkle J. 2007. CDC's Perchlorate Biomonitoring Activities and Study Results. Statement of James 

Pirkle, M.D., Ph.D. Deputy Director for Science National Center for Environment Health Centers 

for Disease Control and Prevention U.S. Department of Health and Human Services, Testimony, 

Committee on Energy and Commerce, Subcommittee on Environment and Hazardous Materials, 

United States House of Representatives Wednesday, April 25, 2007. 

Pop VJ, Brouwers EP, Vader HL, Vulsma T, van Baar AL, de Vijlder JJ. 2003. Maternal 

hypothyroxinaemia during early pregnancy and subsequent child development: A 3-year follow-up 

study. Clin Endocrinol (Oxf) 59:282-288. 

Stanbury JB, Wyngaarden JB. 1952. Effect of perchlorate on the human thyroid gland. Metab Clin 

Exp 1:533-539. 

Tellez RT, Chacon PM, Abarca CR, Blount BC, Landingham CB, Crump KS, et al. 2005. Long-term 

environmental exposure to perchlorate through drinking water and thyroid function during 

pregnancy and the neonatal period. Thyroid 15:963-975. 

Tonacchera M, Pinchera A, Dimida A, Ferrarini E, Agetti P, Vitti P, Ferruccio S, Crump K, Gibbs J. 

2004. Relative potencies and additivity of perchlorate, thiocyanate, nitrate and iodine on the 

inhibition of radioactive iodine uptake by the human sodium iodine symporter. Thyroid 14:1012-19. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Tran N, Valentin-Blasini L, Blount BC, McCuistion CG, Fenton MS, Gin E, Salem A, Hershman 

JM. 2008. Thyroid-stimulating hormone increases active transport of perchlorate into thyroid cells. 

Am J Physiol Endocrinol Metab 294(4):E802-6. 

Woodruff TJ, Zeiss L, Axelrad DA, Guyton KZ, Janssen S, Miller M, Miller GG< Schwartz JM, 

Alexeef G, Anderson H, Birnbaum L, Bois F, Cogliano VJ, Crofton K, Euling SY, Foster PMD, 

Germolec DR, Gray E, Hattis DB, Kyle AD, Luebke RW, Luster MI, Portier C, Rice DC, Solomon 

G, Vandenberg J, Zoeller RT. 2008. Meeting Report: Moving Upstream-Evaluating Adverse 

Upstream End Points for Improved Risk Assessment and Decision-Making. Environ Health 

Perspect 116:1568-1575. 

Wyngaarden JB, Wright BM, Ways P. 1952. The effect of certain anions upon the accumulation and 

retention of iodide by the thyroid gland. Endocrinol 50:537-549. 

Response: Regarding promulgating a perchlorate standard, see response to comment code 6120; 

regarding the basis for the RfD, see response to comment code 2110; regarding consideration of 

sensitive subpopulations, see responses to comment codes 5225, 5230, and 5240, 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20979 

EPA Comment Code: 6120 

 

Comment: November 28, 2008 

U.S. Environmental Protection Agency Office of Water Docket (Mailcode: 2822T) 1200 

Pennsylvania Avenue, NW Washington, DC 20460 

Comments from the NATURAL RESOURCES DEFENSE COUNCIL on the Drinking Water: 

Preliminary Regulatory Determination on Perchlorate 

Docket EPA-HQ-OW-2008-0692 Federal Register / Vol. 73, No. 198 / Friday, October 10, 2008 

SUMMARY 

On October 10, 2008, EPA announced a preliminary regulatory determination not to set a healthprotective standard perchlorate in drinking water.[FN1: 73 Fed. Reg. 0262 (Oct. 10, 2008).] The 

Federal Register notice states that: "The Agency has determined that a national primary drinking 

water regulation (NPDWR) for perchlorate would not present 'a meaningful opportunity for health 

risk reduction for persons served by public water systems.'" EPA sought comments on whether 

setting a national primary drinking water standard for perchlorate would provide a meaningful 

opportunity for health risk reduction for persons served by public water systems, on the scientific 

data and supporting analyses for this determination, and on its use of a revised physiologically-based 

pharmacokinetics (PBPK) model. With this FR Notice, EPA has proposed a health reference level 

(HRL) of 15 ppb as the maximum contamination level of perchlorate that could be in drinking 

water, and still keep daily human consumption levels from exceeding the reference dose (RfD) of 0.7 

ug/kg/day. 
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After careful review of these documents, NRDC concludes that EPA's determination is legally 

flawed. EPA must regulate a contaminant if it may have an adverse effect on human health, if it is 

known to occur (or there is a substantial likelihood that the contaminant will occur) in public water 

systems with a frequency and at levels of public health concern; and if its regulation would present a 

meaningful opportunity for health risk reduction for persons served by public water systems.[FN2: 

42 U.S.C. [section] 300g-1(b)(1)(A).] For perchlorate, each of these three requirements are met, and 

therefore, underscore that EPA must regulate its presence in drinking water. First, EPA's 

preliminary regulatory determination acknowledges that perchlorate may adversely affect human 

health.[FN3: 73 Fed. Reg. 60275 (Oct. 10, 2008).] Second, as explained in more detail below, despite 

EPA's contention, perchlorate is known to contaminate the drinking water systems serving millions 

of people at levels where adverse human health effects occur. And third, setting an appropriately 

stringent MCL will lead to lower levels of perchlorate ingested by hundreds of thousands of infants, 

thereby offering a concrete and meaningful reduction in human health risks. 

Procedurally and scientifically, EPA has made this preliminary determination in an arbitrary and 

capricious manner. Procedurally, the FR Notice announcing EPA's preliminary determination was 

issued for public comment even before EPA had received the peer review report on the PBPK 

model, which EPA used to justify the HRL. Moreover, it is our understanding that EPA is still 

awaiting peer review comments on the proposed HRL itself. The preliminary determination also 

fails to address the recommendations of the Science Advisory Board Drinking Water Committee 

(SAB DWC). Scientifically, the basis for EPA's determination fails to appropriately incorporate data 

demonstrating population level effects at environmentally relevant levels of exposure. In effect, this 

data severely undercuts EPA's conclusion that there would not be a sufficient benefit for protecting 

public health by setting a drinking water standard for perchlorate. The agency’s apparent decision to 

ignore relevant scientific information, in reaching a decision not to regulate this dangerous and 

widespread drinking water contaminant is not a proper exercise of EPA's decision-making process. 

Instead of rushing forward without the benefit of full consideration of the most recent scientific 

evidence (and scientific advice), EPA should carefully review and analyze the results of the peer 

review of the PBPK model and the HRL, allow the public an opportunity to review and analyze 

those results, and request an SAB DWC review prior to making a determination on how to address 

perchlorate contamination. EPA's failure to fully consider the existing data on the effects of 

perchlorate on vulnerable sub-populations, and short-circuit the process of peer review and public 

comment on the models upon which their determination is based, is arbitrary and capricious. 

Furthermore, EPA’s conclusion regarding the potential health benefits of setting a drinking water 

standard for perchlorate is in error, and its preliminary decision not to set a regulatory standard for 

perchlorate, if finalized, would violate the Safe Drinking Water Act. 

Response: 

EPA has reversed its October 2008 preliminary determination not to develop an NPDWR for 

perchlorate and now concludes, based on the analysis presented in the final regulatory 

determination, that there is a substantial likelihood that perchlorate will occur in public water 

systems with a frequency and at levels of public health concern. The Agency has determined that 

regulation of perchlorate presents a meaningful opportunity to reduce health risk for persons served 

by public water systems. 

Please see the response to comment code 6120. EPA disagrees with the commenter’s statement that 

procedurally and scientifically, the preliminary regulatory determination for perchlorate was made in 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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an arbitrary and capricious manner. EPA considers the best available science when developing 

drinking water standards, as required by the 1996 amendments to the Safe Drinking Water Act. In 

applying these principles, "best available" usually refers to the availability at the time an assessment is 

made. In the August 2009 notice, EPA stated that it was re-evaluating how best to incorporate the 

PBPK modeling analysis into its evaluation of perchlorate — if at all. The Agency sought comments 

on ways to use the PBPK modeling analysis to inform the regulatory determination. Regarding the 

commenter’s concern about the peer review of the PBPK model, please see the response to 

comment code 6400. Additionally, EPA discussed the key scientific issues raised by external peer 

reviewer commenters on the Interim Drinking Water Health Advisory for perchlorate in the August 

2009 notice and in today’s notice. A summary of peer review comments and EPA responses on the 

Interim Drinking Water Health Advisory are available in the docket for today’s notice (Docket ID 

No. EPA–HQ–OW–2009–0297) at http://www.regulations.gov. EPA has further considered peer 

reviewer and public comments regarding the use of the PBPK model to inform today’s regulatory 

determination for perchlorate, please see response to comment ID 20432 in comment code 5220 for 

a more detailed discussion. 

EPA disagrees that the PBPK model should have been reviewed by the SAB because the model and 

draft report underwent a formal external peer review by eight experts in accordance with EPA 

guidance (see response to comment code 6400). Additionally, per SDWA, EPA will consult with the 

SAB prior to proposal of the perchlorate maximum contaminant level goal and NPDWR. 

Please see the response to comment code 5220 for a further discussion of EPA’s determination that 

regulation of perchlorate in drinking water systems presents a meaningful opportunity for health risk 

reduction for persons served by public water systems. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20982 

EPA Comment Code: 6120 

 

Comment: Based upon the evidence in the record, as discussed in greater detail below, NRDC 

urges EPA to reverse course, and set a national primary drinking water standard for perchlorate that 

is protective of sensitive sub-populations. EPA should not set a HRL at 15 ppb; rather, given the 

most current data available, NRDC believes that that a truly health protective standard would fall 

below 1 ppb. 

Response: See response to comment code 6120. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20988 

EPA Comment Code: 6120 

 

Comment: NRDC strongly objects to EPA's preliminary determination on perchlorate because the 

conclusions are not based on a comprehensive review of the best available science (as explained in 

more detail below) and are not supported by the PBPK model findings, or by EPA's expert scientific 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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advisors on the Children's Health Protection Advisory Committee.[FN22: Letter from Melanie 

Marty to Administrator Johnson regarding Preliminary Regulatory Determination on Perchlorate 

(November 3, 2008, PDF) 

http://yosemite.epa.gov/ochp/ochpweb.nsf/content/perchlorateletter.htm/$file/Per 

chlorateLetter.pdf] In fact, drinking water that is contaminated with perchlorate at the HRL would 

leave infants and young children exposed to excessive and unsafe levels of this toxic chemical. 

Response: Please see the response to comment ID 20979 under comment code 6120. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 21003 

EPA Comment Code: 6120 

 

Comment: CONCLUSION 

EPA should not finalize its preliminary determination not to regulate perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: Rebecca Connolly 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1882 

EPA Comment ID: 21036 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Please stop allowing perchlorate to filter into our drinking water. 

Thank you. 

Sincerely, Rebecca Connolly 116 Hume Ave. Alexandria, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Michael Suttles 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1880 

EPA Comment ID: 21037 

EPA Comment Code: 6120 

 

Comment: EPA Water Docket 

To Whom it May Concern: 
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I'm a student and a voter in Virginia and I'm concerned about water quality. Perchlorate is a 

dangerous chemcial often found in water and has been discovered to be present in 37 states. 

Therefore, it must be regulated in order to protect our health. 

Sincerely, Michael Suttles 411A E Howell Ave. Alexandria, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Maggie Geist 

Commenter Organization: Association to Preserve Cape Cod (APCC) 

EPA Document ID: EPA-HQ-OW-2008-0692-2083 

EPA Comment ID: 21104 

EPA Comment Code: 6120 

 

Comment: November 26, 2008 

Water Docket Environmental Protection Agency Mail Code: 2822T 1200 Pennsylvania Ave., NW 

Washington, DC 20460 RE: Docket ID No. EPA-HQ-OW-2008-0692 

To Whom It May Concern: 

The Association to Preserve Cape Cod (APCC) is a non-profit environmental organization 

dedicated to the preservation of Cape Cod's natural resources and quality of life. Founded in 1965 

and currently representing over 5,500 members, APCC is the oldest and largest environmental 

organization on Cape Cod. 

On behalf of APCC, I am pleased to submit comments on the Preliminary Regulatory 

Determination on Perchlorate in Drinking Water proposed by USEPA. APCC urges USEPA to 

reconsider its determination to not regulate perchlorate. There are a significant number of water 

resources across-the country that contain perchlorate; 35 states have detected dangerous levels of 

perchlorate in drinking water. The full extent of the pervasiveness of perchlorate is still unknown. In 

addition to drinking water, it is also found in produce and dairy products, likely coming from water 

used to irrigate crops and water livestock. Perchlorate is also extremely persistent, meaning it has the 

potential to migrate far from the source of contamination, polluting entire watersheds. 

The health consequences of ingesting perchlorate are significant, largely impact infants, and can be 

transferred maternally to a fetus. Perchlorate causes a reduction of the thyroid hormone production. 

The thyroid hormone is critical for muscle and brain development. Where protecting the health and 

development of children is of paramount importance, such risks from perchlorate are unacceptable. 

Establishing a regulatory limit on perchlorate in drinking water is an important step in reducing this 

risk nationwide. 

Sincerely, 

Maggie Geist 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 868 of 1099

Commenter Name: Peggy Shiffrin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2084 

EPA Comment ID: 21105 

EPA Comment Code: 6120 

 

Comment: Peggy Kobacker Shiffrin 2811 Chesterfield Place, NW Washington, DC 20008 

November 20, 2008 

Water Docket, EPA, Mailcode 2822T 1200 Pennsylvania Avenue, NW Washington, DC 20460 

Docket ID No. EPA-HQ-OW-2008-0692 

To whom it may concern: 

I urge you to reverse your decision and set a federal limit n perchlorate in drinking water. 

Perchlorate is a nationwide problem and has health impacts at lower levels than previously thought. 

Please protect public health, especially infants and children, by regulating perchlorate. 

Thank you, 

Peggy Shiffrin 

Response: See response to comment code 6120. 

Commenter Name: Teresa Jordan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2086 

EPA Comment ID: 21107 

EPA Comment Code: 6120 

 

Comment: 3152 Shad Court Simi Valley, CA 93063 November 16, 2008 

Water Docket USEPA Mailcode: 2822T 1200 Pennsylvania Avenue, N.W. Washington, DC 20460 

Re: DOCKET ID No. EPA-HQ-OW-208-0692 (Preliminary Regulatory Determination on 

Perchlorate -- Reopening of Public Comment Period (Novemeber 28, 2008 Deadline)). 

Dear Mr. Grumbles, and Mr. Burneson: 

I am writing to ask that the Agency initiate development of a national regulation for perchlorate in 

drinking water. 

Mr. Grumbles and Mr. Burneson, as a concerned citizen who has followed the significant impacts to 

people's and animals' health from water, soil, and air contamination due to DOW, NASA, and 

Rockwell International/Boeing Company rocket engines and nuclear reactors testing, lasers and 

other activities on the Santa Susana Field Laboratory (the SSFL, located in Simi Hills, in Ventura 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 869 of 1099

County, California) for 19+ years, I was shocked when I read that the Agency would not be 

regulating perchlorate in drinking water systems around the Nation beacuse the determination 

significant ramifications for the County of Ventura, and, most especially, the City of Simi Valley!!! 

Mr. Grumbles and Mr. Burneson, if I ever thought there was hope to finally have the SSFL included 

in the USEPA's Superfund List because of the Agency's cumulative findings, such grave news -- this 

determination coming years after perchlorate was included on the first (March 2, 1998) and second 

(February 24, 2005) Contaminant Candidate Lists (CCLs) -- just snuffed out the small light at the 

end of this very long tunnel! What travesty for the public trust, and the environmental justice 

program!!! 

Mr. Grumbles and Mr. Burneson, this determination will allow the Ventura Countrywide MS4 

NPDES Permit, and the municipal NPDES permits for the Cities of Thousand Oaks and Simi 

Valley, and the Camarillo Sanitary District waste water treatment plants to breeze through the Los 

Angeles Regional Water Control Board (LARWQCB) public review and comment period, and 

public hearing next time around -- no wonder the two subjects dropped off the radar. 

Response: See response to comment code 6120. 

Commenter Name: Frederick Behnke Jr. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2087 

EPA Comment ID: 21110 

EPA Comment Code: 6120 

 

Comment: November 24, 2008 

Water Docket, EPA Mail Code 2822T 1200 Pennsylvania Ave Washington DC 20460 Attention: 

Docket No. EPA-HQ-OW-2008-0692 

To Whom It May Concern: 

Please keep our drinking water safe by regulating the amount of perchlorate allowed in our drinking 

water. There has been scientific proof that perchlorate can lead to thyroid problems in pregnant 

women, newborns, and infants. A primary drinking water regulation is needed to protect the public 

health. Sincerely, 

Frederick E Behnke, Jr. 1470 Mordor Lane Hanover MD 21076 

Response: See response to comment code 6120. 

Commenter Name: Anne Eberhardt 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2088 

EPA Comment ID: 21111 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 870 of 1099

Comment: Water Docket, EPA Mail Code 2822T 1200 Pennsylvania Ave Washington, DC 20460 

Attn: DOcket ID EPA-HQ-OW-2008-0692 

To Whom it May Concern 

It has come to my attention that the EPA has announced its intention to not regulate perchlorate in 

drinking water. 

Please reverse that decision immediately. Do not ruin our drinking water which has always been 

good. Please regulate it. 

Anne Eberhardt 1213 Tacoma St Allentown, PA 18109 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2089 

EPA Comment ID: 21112 

EPA Comment Code: 6120 

 

Comment: Perchlorate contamination is a nationwide problem which needs to be addressed. 

Perchlorate has health impacts at lower levels than previously thought. A National Primary drinking 

water regulation is needed to protect our drinking water from pollutants. 

The Food and Drug Administration found perchlorate in 74% of foods it tested. We don't need 

more perchlorate coming from our drinking water. 

For the health of everyone something need to be done, so please keep perchlorate out of our 

drinking water. 

Sincerely 

Response: See response to comment code 6120. 

Commenter Name: Tina, Mona, and Ahmed Saleh 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2090 

EPA Comment ID: 21113 

EPA Comment Code: 6120 

 

Comment: Water Docket, EPA Mail Code 2822T 1200 Pennsylvania Ave. Washington, DC 20460 

Attn: Docket ID No. EPA-HQ-OW-2008-0692 

To Whom it May Concern, 

We need good, clean, purified water to keep this nation healthy. My mother has been going to the 

Doctor's for a whole year now because the area of her kidney has been bothering her and the 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 871 of 1099

Doctor's say it's due to the unhealthy, unpurified water she has been drinking. Perchlorate 

contamination is a worldwide problem and has health impacts at lower levels than previously 

thought. Its already effecting 37 states. 37 states! That's more than half of the U.S. We need to stay 

healthy, we need cleaner water. 

Sincerely, Tina Saleh Mona Saleh Ahmed Saleh 1635 E. Greanleaf St. Allentown, PA 18109 

Response: See response to comment code 6120. 

Commenter Name: Ellen Blaschinski, M.B.A., R.S. 

Commenter Organization: Regulatory Services Branch, Connecticut Department of Public Health 

EPA Document ID: EPA-HQ-OW-2008-0692-2091 

EPA Comment ID: 21117 

EPA Comment Code: 6120 

 

Comment: EPA's opportunity to address perchlorate is substantial from a public health perspective 

given the risks this chemical can pose to early life development and its potential for occurrence in 

public water supplies. Sensitive test methods exist as do practical treatment options. Therefore, we 

urge EPA to reconsider its decision to not regulate perchlorate. In that reevaluation, EPA should 

utilize methodologies that ensure protection of all potentially sensitive receptors from the antithyroid effects of this chemical. 

Please let us know if you would like additional information regarding the Connecticut Department 

of Public Health's comments on this important matter. 

Sincerely, Ellen Blaschiriski, M.B.A., R.S., Chief, Regulatory Services Branch 

Response: See response to comment code 6120. 

Commenter Name: Bonnie Ludwick 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2092 

EPA Comment ID: 21118 

EPA Comment Code: 6120 

 

Comment: OW-2008-0692= 

To Whom It May Concern 

Please regulate Perchlorate out of our drinking water now! Thanks Bonnie S. Ludwick 30 W. High 

St Hellertown, PA 18055 

Water Docket, EPA, Mailcode 2822T 1200 Pennsylvania Ave. Washington, DC 20460 Attn: Docket 

ID No. EPA-HQ-OW-2008-0692 

Response: See response to comment code 6120. 

Commenter Name: (illegible) 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 872 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2093 

EPA Comment ID: 21119 

EPA Comment Code: 6120 

 

Comment: -OW-2008-0692 11/13 Dear EPA, 

Learning of the side effects of perchlorate contaminations (thyroid issues, birth deffects, loss of 

[illegible] etc) that come from military bases, fireworks, construction sites, and so on. If you could 

do a regular water check (weekly or daily)....Just to make sure the water that your fellow citizens 

consume daily even babies OR at least inform us ASAP that the levels are high so we could at least 

use bottled water (while you filter the water) it would prevent so many problems. 

Thank you, high school student nurses aid 

Response: See response to comment code 6120. 

Commenter Name: Juanita Velez 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2094 

EPA Comment ID: 21120 

EPA Comment Code: 6120 

 

Comment: 631 Oakcrest Wyoming MI 49508 

Stephan Johnson, 

Clean Water is important to every living thing and its important to keep the water safe + pure for 

the future generations. To help regulate green house gas emissions under the Clean air act. 

thank you Juanita Velez 

Response: This is not a comment, no response is needed. 

Commenter Name: Clair Edwards 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2095 

EPA Comment ID: 21121 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Please keep toxins out of our water these are harmful to our kids!!! 

Thank you Clair Edwards 2422 Taylor Ave Alex. VA 22302 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 873 of 1099

Commenter Name: John Hall 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2096 

EPA Comment ID: 21122 

EPA Comment Code: 6120 

 

Comment: To: EPA 

Perchlorate is unsafe -- hurts kids, toxic. 

Please stop. 

John Hall 213 Woodland Ter Alexandria VA 22303 

Response: See response to comment code 6120. 

Commenter Name: Andrew Freed 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2097 

EPA Comment ID: 21123 

EPA Comment Code: 6120 

 

Comment: U.S. Environmental Protection Agency, 

My name is Andrew Freed and I am writing you in regards to an issue that has been brought to my 

attention recently. A young lady I encountered informed me of the epidemic surrounding 

perchlorate in drinking water. She educated me on the concerns and factors if we do not regulate the 

amounts of perchlorate in our drinking water. 

One of the concerns she brought up is that perchlorate contamination is a nationwide problem. Not 

only does this effect my drinking water personally but this concerns me because, coming from a 

larger family, we are spread nationwide and their health is just as important to me as my own. 

Another concern is that the EPA is ignoring the fact that lower levels of perchlorate in our drinking 

water does have impacts on health, more than they previously thought. One of the risks is 

impairment to the thyroid gland. Many people aren't aware of the importance of that gland. It not 

only controls growth it also controls development and metabolism. When tampered with, these 

impacts are especially harmful to children and fetuses. 

And a factor that really stuck home is the lack of concern for our nation from the EPA. In our 

world today, we have to start somewhere in, order to make change. Our newly appointed president 

wants to make change and this might be a step in the right direction. A national primary drinking 

water regulation is needed to protect public health. Citizens of the United States are not aware of 

many of the risks they face everyday. We rely on government agencies to ensure our safety when it 

comes to everyday exposure to things we take for granted like the water:we drink and the air we 

breathe. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 874 of 1099

All I am asking for is that you take a look at the concerns and think to yourself would you or your 

loved ones want to drink water that is contaminated? 

Thank you for your time. Sincerely, Andrew Freed 

Response: See response to comment code 6120. 

Commenter Name: Edward and Colleen Flok 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2098 

EPA Comment ID: 21124 

EPA Comment Code: 6120 

 

Comment: Water Docket, EPA Mail Code 2822T 1200 Pennsylvania Ave Washington, DC 20460 

Attn: Water Docket ID No. EPA-HQ-OW-2008-0692 

To Whom It May Concern 

Perchlorate is a widespread contaminate. It is a nationwide problem, that has health impacts at lower 

levels than previously thought. Perchlorate contamination threatens public health. Traces of 

Perchlorate have been detected in people, the foods we eat, and groundwater. 

I am now aware the United States Environmental Protection Agency (EPA) has announced its 

intention not to regulate Perchlorate in drinking water. I am writing this letter to ask that the EPA 

reverse there decision. A national primary drinking water regulation is needed to protect public 

health. 

Thank you. Respectfully, Dr. Edward Flok 1335 Jefferson Street Hellertown, Pa. 18055 610-838-

4851 Email: eddieflok57@gmail.com 

Respectfully, Colleen M. Flok 1335 Jefferson Street Hellertown, Pa. 18055 Email: 

colleenf58@aol.com 

Response: See response to comment code 6120. 

Commenter Name: Ann Mowrey 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2099 

EPA Comment ID: 21125 

EPA Comment Code: 6120 

 

Comment: November 20, 2008 To Whom It May Concern: 

I am concerned with keeping Perchlorate out of our drinking water. Perchlorate contamination is a 

nationwide problem and has health impacts at lower levels than previously thought. A national 

primary drinking water regulation is needed to protect public heath. 

Thank you Ann Mowrey 136 Roth Ave. Hellertown, PA 18055 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 875 of 1099

Water Docket, EPA Mail Code 2822T 1200 Pennsylvania Ave Washington, DC 20460 Attn: Water 

Docket ID No. EPA-HQ-OW-2008-0692 

Response: See response to comment code 6120. 

Commenter Name: Kristin Verrastro 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2100 

EPA Comment ID: 21126 

EPA Comment Code: 6120 

 

Comment: U.S. Environmental Protection Agency, 

My name is Kristin Verrastro and I am writing you in regards to the recent concerns of regulating 

perchlorate in our nations drinking water. I am a resident of Pennsylvania and have been recently 

informed about this growing problem. 

I am not sure if you are aware of the dangers of the perchlorate being in our drinking water but it 

does not just affect a specific area. It is a nationwide problem and impacts health issues at lower 

levels than previously thought. One of the health problems that perchlorate can impair is the thyroid 

gland. As a person who deals with thyroid issues personally this has raised a red flag in my life. If 

you are not aware, the thyroid glad controls growth, development and metabolism, which can be 

extremely harmful if tampered with to children and fetuses. 

Also speaking as a human being needing water to survive everyday life, the excessive amounts of 

perchlorate in our drinking water needs to be regulated to protect public health. I am 26 years old 

woman and some day would like to have children and the risk that they may become sick because of 

something that we as a nation could have fixed is also something that raises a red flag in my life. 

All I am asking for is that you take a look at the concerns and think to your self, would you or your 

loved ones want to drink water that is contaminated? 

Thank you for your time. 

Kristin E. Verrastro 

Water Docket, EPA Mail Code 2822T 1200 Pennsylvania Ave Washington, DC 20460 Attn: Water 

Docket ID No. EPA-HQ-OW-2008-0692 

Response: See response to comment code 6120. 

Commenter Name: Kemmerer Family 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2101 

EPA Comment ID: 21127 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 876 of 1099

Comment: Water Docket, EPA Mail Code 2822T 1200 Pennsylvania Ave Washington, DC 20460 

Attn: Water Docket ID No. EPA-HQ-OW-2008-0692 

To the US Environmental Protection Agency, 

You need to reverse your decision and regulate perchlorate in drinking water. Perchlorate 

contamination is a nationwide problem and has health effects at lower levels than previously 

thought. A national primary drinking water regulation is needed to protect public health. Please 

reconsider your decision. This is a big health issue. 

The Kemmerer Family 

Response: See response to comment code 6120. 

Commenter Name: Katie and Frank Nemeth Hummer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2102 

EPA Comment ID: 21128 

EPA Comment Code: 6120 

 

Comment: November 13, 2008 

Water Docket, EPA Mail Code 2822T 1200 Pennsylvania Ave Washington, DC 20460 Attn: Water 

Docket ID No. EPA-HQ-OW-2008-0692 

Attention: U.S. Environmental Protection Agency (EPA): 

I am writing to inform you of some recent information I have obtained from an outside source. Did 

you know that perchlorate is a nationwide problem and has health impacts at lower levels than 

previously thought? Did you know that a national primary drinking water regulation is needed to 

protect public health? 

It is your duty to take close investigation on this matter that we, as the people, have support and 

protection in this issue. Please take this information and investigate solutions on this serious issue 

concerning something we all need for survival. 

Cordially, Katie Hummer Frank Nemeth 

Response: See response to comment code 6120. 

Commenter Name: Sandra Hoag 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2103 

EPA Comment ID: 21129 

EPA Comment Code: 6120 

 

Comment: 11/18/08 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 877 of 1099

Sandra L. Hoag 806 Crescent Drive Alexandria, VA 22302 

Water Docket, EPA, Mailcode 2822T 1200 Pennsylvania Ave. NW Washington, DC 20460 Docket 

ID No. EPA-HQ-0W 2008-0692 

To Whom it May Concern: 

I urge you to reverse your decision and set a federal limit for perchlorate in drinking water. 

Perchlorate is a nationwide problem and has greater health impacts at lower levels than previously 

thought. Please protect public health, especially infants and children, by regulating perchlorate. 

Sincerely, Sandra Hoag 

Response: See response to comment code 6120. 

Commenter Name: April Verlo 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2104 

EPA Comment ID: 21130 

EPA Comment Code: 6120 

 

Comment: 11/18/08 

To: EPA Water Docket 

I am an environmental scientist and concerned about perchlorate. It affects children and is 

widespread. Please see that it is regulated. 

April Verlo 401 Tennessee Alexandria, VA 22305 

Response: See response to comment code 6120. 

Commenter Name: Elizabeth Johnson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2105 

EPA Comment ID: 21131 

EPA Comment Code: 6120 

 

Comment: Elizabeth Johnson 2704 Davis Avenue Alexandria, VA 22302 November 19, 2008 

Water Docket, EPA, Mailcode 2822T 1200 Pennsylvania Avenue, NW Washington, DC 20460 Re: 

Docket ID No. EPA-HQ-OW-2008-0692 

To Whom It May Concern: 

I urge you to reverse your decision and set a federal limit for perchlorate in drinking water. 

Perchlorate is a nationwide problem and has health impacts at lower levels than previously thought. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 878 of 1099

Please protect public health, especially the health of infants and children, by regulating perchlorate. 

With five grandchildren I am particularly concerned about the impact of your decision on the 

standards set for the water they drink. 

Sincerely, Elizabeth Johnson 

Response: See response to comment code 6120. 

Commenter Name: Toni Soule 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2106 

EPA Comment ID: 21132 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Please regulate toxins in our drinking water, especially perchlorate, which is dreadful! 

Sincerely, Toni Soule 2400 Clemson Mills Rd Alex., VA 22302 

Response: See response to comment code 6120. 

Commenter Name: Lorraine Keir 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2107 

EPA Comment ID: 21133 

EPA Comment Code: 6120 

 

Comment: 3307 Elmore Drive Alexandria, VA 22302 

November 16, 2008 

Water Docket, EPA, Mailcode 2822T 1200 Pennsylvania Avenue, NW Washington, DC 20460 

Docket ID No. EPA-HQ-OW-2008-0692 

To Whom It May Concern: 

I urge you to reverse your decision and set a federal limit for perchlorate in drinking water. I have a 

small child and am concerned about the effects of perchlorate on her health and development. 

Please protect public health, especially those of infants and children like my daughter, by regulating 

perchlorate. 

We have a right to clean drinking water and the government should do all in it's power to ensure our 

water is safe. Thank you for your consideration. 

Sincerely, 

Lorraine P. Keir 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 879 of 1099

Response: See response to comment code 6120. 

Commenter Name: J.B. Poersch 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2108 

EPA Comment ID: 21134 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Regulate perchlorate. Its too big a risk for my family. 

Sincerely J.B. Poersch 608 Woodland Tr. Alexandria, VA 22302 

Response: See response to comment code 6120. 

Commenter Name: Laura Ahehan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2109 

EPA Comment ID: 21135 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Please regulate perchlorate and other harmful toxins. Our neighborhood knows it is dangerous for 

our children. 

Laura Ahehan 2414 Davis Ave. Alexandria, VA 22302 

Response: See response to comment code 6120. 

Commenter Name: Michael Aldanli 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2110 

EPA Comment ID: 21136 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

As a concerned citizen, I believe perchlorate should be eliminated from the environment to the 

maximum extent feasible. 

Michael Aldanli 3400 Alabama Ave. Alexandria, VA 22305 

Response: See response to comment code 6120. 

Commenter Name: George B. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 880 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2113 

EPA Comment ID: 21954 

EPA Comment Code: 6120 

 

Comment: Nov. 20, 2008 

E.P.A. 

Please work to regulate or better yet eliminate perchlorate from everyone's drinking water. 

Thanks, 

George B. [illegible] 1044 Springhill Way Gambrills, MD 21054 301-621-7881 

Response: See response to comment code 6120. 

Commenter Name: Ron W 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2114 

EPA Comment ID: 21956 

EPA Comment Code: 6120 

 

Comment: Nov. 17, 2008 

Dear EPA 

I urge you to regulate the amount of perchlorate in our drinking water supply. 

Sincerely, 

Ron W [illegible] 3324 [illegible] Lane Brookeville, Md 20833 

Response: See response to comment code 6120. 

Commenter Name: T Siegel 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2115 

EPA Comment ID: 21958 

EPA Comment Code: 6120 

 

Comment: EPA Water Docket: 

I am a Wash DC voter. Perchlorate is a dangerous chemcial found in 37 states - it gets into water 

and therefore must be regulated. 

T. Siegel 1383 28th St NW Wash DC 20007 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 881 of 1099

Response: See response to comment code 6120. 

Commenter Name: Matt Lewis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2116 

EPA Comment ID: 21965 

EPA Comment Code: 6120 

 

Comment: To All Readers, 

Perchlorate is a harmful chemical found in our drinking water. It is used in Rocket fuel and 

explosives. Every day, citizens ingest thousands of gallons nationally. If something is not done soon, 

This great country will be left a barren wasteland with no humans to care for it and all our efforts 

will have been wasted. Perchlorate can cause massive problems both physically and mentally to any 

human that ingests it. 

Response: See response to comment code 6120. 

Commenter Name: Matt Lewis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2116 

EPA Comment ID: 21967 

EPA Comment Code: 6120 

 

Comment: This country strives not on its technological booms, but the minds that drive them. If 

we do not act now, it'll soon be too late and what use will these technological advances be to us 

then. Without the bright minds of our citizens, what use is a government who wouldn't act when it 

had the chance. 

If the EPA does not do something to prevent further problems now, then there is no point in 

allowing them to stay as a federal agency anymore. The EPA has a responsibility to act now and as 

such should proceed with all haste. No Bureaucratic procedure or code should stop them. No effort 

should be made to stop them from proceeding to fulfill their duty to this great country. 

There are many sources of perchlorate contamination including many military bases, fireworks 

manufacturers, and blasting at construction sites. If there were more routine testing then perhaps the 

problem could be more properly identified. Currently perchlorate has been found in 37 states, and in 

public water systems serving over 20 million people. 

 Respectfully, Matt Lewis 

Response: See response to comment code 6120. 

Commenter Name: Christine Wojciechowski 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2118 

EPA Comment ID: 21987 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 882 of 1099

 

Comment: November 14, 2008 

To Whom It May Concern: 

Perchlorate is a harmful chemical that can cause health problems if ingested. This chemical should 

not be in our drinking water. We need regulation to protect public health. 

Thank you, Christine Wojciechowski 

Response: See response to comment code 6120. 

Commenter Name: John Sherry 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2120 

EPA Comment ID: 21990 

EPA Comment Code: 6120 

 

Comment: Water Docket, EPA Mailcode 2822T, 1200 Pennsylvania Ave., Washington, D.C. 20460 

We live very close to a military base and to dump site. We need routine testing and a drinking water 

regulation 

Thank you John Sherry 

Response: See response to comment code 6120. 

Commenter Name: Eugene A. Smell 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2122 

EPA Comment ID: 21998 

EPA Comment Code: 6120 

 

Comment: 20 November 2008 

To: EPA 

Please continue to regulate perchlorate in drinking water. 

Thank you 

Eugene A. Smell 

Response: See response to comment code 6120. 

Commenter Name: Barbara A. Smell 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2123 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 883 of 1099

EPA Comment ID: 21999 

EPA Comment Code: 6120 

 

Comment: November 20, 2008 

EPA 

To whom it may concern: 

Please continue to regulate perchlorate in drinking water. 

Barbara A. Smell 

Response: See response to comment code 6120. 

Commenter Name: Sarah Favrao 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2124 

EPA Comment ID: 22011 

EPA Comment Code: 6120 

 

Comment: November 11. 2008 

To whom it may concern: 

I am writing to urge the EPA to reverse their decision to not regulate perchlorate in our drinking 

water. Studies have shown that this it is a nationwide problem with ground water contamination, 

and has detrimental health effects for all, but especially fetuses and young children. From what I 

have read from Clean Water Action's literature, I believe perchlorate should be regulated, to protect 

my health and my family's health. 

Sarah Favrao 

Response: See response to comment code 6120. 

Commenter Name: Robert J 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2125 

EPA Comment ID: 22012 

EPA Comment Code: 6120 

 

Comment: 11-10-08 

To: Water Docket EPA, mailcode 2822T 1200 Penn. Ave Wash DC, 20460 ATTN: Docket ID No 

EPA-HQ-OW-2008-0692 

Dear Sirs, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 884 of 1099

I believe perchlorate contamination is a national problem and has health impacts at lower levels than 

previously thought. 

A national primary drinking water regulation is needed to protect the public health. 

Regards Robert J [illegible] 103[illegible] Askewton Road Severna Park, MD. 21146 

Response: See response to comment code 6120. 

Commenter Name: Elaine 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2127 

EPA Comment ID: 22013 

EPA Comment Code: 6120 

 

Comment: November 17, 2008 

EPA, 

I am a concerned Alexandria Virginia resident. 

I learned about your decision not to regulate perchlorate and am upset with this decision 

It is a threat to human health and I asking you to reconsider and regulate. 

Thank you Elaine [illegible] 

Response: See response to comment code 6120. 

Commenter Name: 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2128 

EPA Comment ID: 22014 

EPA Comment Code: 6120 

 

Comment: To whom it may concern: 

Perchlorate is not something I want in my water. For the sake of our nation's young people, please 

consider regulating this threat to our DC water supply! 

Sincerely, [illegible] 3609 N Street Washington, DC 20007 

Response: See response to comment code 6120. 

Commenter Name: Anna Sannes 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2129 

EPA Comment ID: 22015 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 885 of 1099

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

I'd just like to take this opportunity to remind you how important it is that we keep perchlorate out 

of our water systems. As a daycare worker, I spend most of my time with children, and the thought 

of them being hurt developmentally, by water, is frightening. Please help keep our children safe; 

keep perchlorate out of the water. 

Thanks, Anna Sannes LXR 217 Georgetown University Box 578853 Washington, DC 20057 

Response: See response to comment code 6120. 

Commenter Name: Katherine Rogers 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2130 

EPA Comment ID: 22016 

EPA Comment Code: 6120 

 

Comment: To EPA - 

Please don't put perchlorate in our water. 

3263 O St, NW Washington, DC 20007 

Katherine Rogers 

Response: EPA does not put perchlorate into water. EPA has determined that perchlorate in 

drinking water requires regulation. See response to comment code 6120. 

Commenter Name: Courtney Stonestreet 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2131 

EPA Comment ID: 22017 

EPA Comment Code: 6120 

 

Comment: 12 November 2008 

Courtney Stonestreet 3378 Martha Custis Drive Alexandria, Virginia 22302 

Dear EPA - 

We need clean, healthy water in Virginia! Perchlorate needs to be labeled as a harmful toxin and kept 

out of our drinking. Please do you part with the public's health in mind and keep this chemical out 

of the water. 

Sincerely, Courtney Stonestreet 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 886 of 1099

Response: See response to comment code 6120. 

Commenter Name: 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2132 

EPA Comment ID: 22018 

EPA Comment Code: 6120 

 

Comment: To: EPA Water Docket 

I am a Virginia voter and a grandmother concerned about the state of the planet our grandchildren 

will inherit. 

Perchlorate is a dangerous chemical found in 37 states. Therefore, since affects children when it gets 

into water, it should be regulated. 

Sincerely, 

[illegible] 1510 Dogawood Drive Alexandria, VA 22302 

Response: See response to comment code 6120. 

Commenter Name: Lani Weatherhead 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2133 

EPA Comment ID: 22019 

EPA Comment Code: 6120 

 

Comment: 11/12/08 

Dear EPA, 

Please don't put perchlorate in my water. It will hurt my baby. Please regulate what you are allowing 

to get into the water. 

Thank you, 

Lani Weatherhead 3755 Gunston Alexandria, VA 22302 

Response: EPA is not putting perchlorate into your water. EPA has determined to regulate 

perchlorate in drinking water. See response to comment code 6120. 

Commenter Name: Jackie Draghi 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2134 

EPA Comment ID: 22020 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 887 of 1099

Comment: 1/22/08 

Dear EPA, 

Please regulate perchlorate and do routine testing for it. 

Sincerely, Jackie Draghi 3775 Gunston Road Alexandria, VA 22302 

Response: See response to comment code 6120. 

Commenter Name: William Webner 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2135 

EPA Comment ID: 22021 

EPA Comment Code: 6120 

 

Comment: November 2008 

To: EPA Water Docket - 

I am a voter and DC resident. Perchlorate is a dangerous chemical found in 37 states. It msut be 

regulated because it gets into water. 

William Webner 1237 30th Street Wash, DC 2007 

Response: See response to comment code 6120. 

Commenter Name: Gladys Billups 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2136 

EPA Comment ID: 22022 

EPA Comment Code: 6120 

 

Comment: TO: EPA From: Gladys Billups 

To Whom It May Concern, 

As a citizen concerned about passing a stringent and decisive clean water act by congress, I request 

that you work with the organization Clean Water Action to ban the use of per chlorate. We as a 

nation should have access to clean and safe water without toxic chemicals. 

Respectfully, Gladys Billups 

Response: See response to comment code 6120. Banning the use of perchlorate is outside the 

scope of this regulatory determination. 

Commenter Name: Kimberly Feeney 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 888 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-2140 

EPA Comment ID: 22023 

EPA Comment Code: 6120 

 

Comment: November 10, 2008 

Environmental Protection Agency 1200 Pennsylvania Avenue Washington, D.C. 20460 

Re: Perchlorate Contamination of Drinking Water 

To Whom It May Concern: 

Perchlorate contamination of drinking water is a public health issue. Until each state, in the United 

States, addresses perchlorate contamination, I believe the EPA must regulate national primary 

drinking water. 

Perchlorate contamination of drinking water is unacceptable. 

Sincerely, Kimberly Feeney 

Response: See response to comment code 6120. 

Commenter Name: Deborah Honecker 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2141 

EPA Comment ID: 22024 

EPA Comment Code: 6120 

 

Comment: Nov. 6, 2008 

To Whom It May Concern, 

Please consider the risks involved with perchlorate contamination. Citizens expect the EPA to 

monitor water quality and locate sources of water contamination. The military, industry, and other 

interests have proven themselves unwilling or inept at self-monitoring, which makes your work that 

much more important. The health and safety of millions of citizens are dependent on actions taken 

by the EPA. 

Thank you, Deborah Honecker 521 Evergreen Rd. Severna Park, MD 21146 

Response: See response to comment code 6120. 

Commenter Name: Linda L Ferguson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2142 

EPA Comment ID: 22025 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 889 of 1099

Comment: Dear EPA, 

I urge you to regulate the amount of perchlorate in our drinking water supply. 

Sincerely, Linda L. Ferguson 602 Persimmon Ct Severna Park, MD 21146 

Response: See response to comment code 6120. 

Commenter Name: Ellie Milleker 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2143 

EPA Comment ID: 22026 

EPA Comment Code: 6120 

 

Comment: Ellie Milleker 112 A Askewton Rd Severna Park, MD 

Water Docket EPA Mailcode 2822T 1200 Pennsylvania Ave. Washington, D.C. 20460 

Re: Docket ID No. EPA-HQ-OW-2008-0692 

I am writing to voice my strong opposition to not put regulations on perchlorate in drinking water. 

Perchlorate contamination is a nationwide problem. A national primary drinking water regulation is 

needed to protect public health. 

Sincerely, Ellie Milleker 

Response: See response to comment code 6120. 

Commenter Name: Kimberly & Justin Vance Carter 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2144 

EPA Comment ID: 22027 

EPA Comment Code: 6120 

 

Comment: November 20, 2008 

Water Docket EPA Mailcode 2822T 1200 Pennsylvania Ave. Washington, DC 20460 ATTN: 

Docket ID No. EPA-HQ-0W-2008-0692 

Dear Sir/Madam: 

I understand that the EPA does not intend to regulate perchiorate in drinking water. I understand 

that perchlorate is a human health hazard causing damage to the thyroid gland. I also understand 

that perchlorate is currently detected in 37 states and in public drinking water thus affecting over 20 

million Americans. This is unacceptable. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 890 of 1099

I urge the EPA to rethink it's position on this issue. The U.S. is the wealthiest nation on the planet 

and there is no excuse for Americans to be exposed to this toxin by simply drinking a glass of water. 

Thank you in advance for your prompt attention to this matter. 

Sincerely, Kimberly Carter & Justin Vance 

Response: See response to comment code 6120. 

Commenter Name: Breona Keller 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2145 

EPA Comment ID: 22028 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

I think you should try to cleanse the water that we wash and drink in. If we want our world back to 

normal we have to sacrifice a lot of things. As I was reading the sheet, it said perchlorate is a harmful 

chemical used in rocket fuel and explosives. And it impacts are especially harmful to children and 

fetuses. Stop doing harm to our planet and to the human beings that live in it. Just take it out of our 

water. 

Thank You, Breona Keller 

Response: See response to comment code 6120. 

Commenter Name: Linda E. Lozier 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2146 

EPA Comment ID: 22029 

EPA Comment Code: 6120 

 

Comment: November 6, 2008 U.S. Environmental Protection Agency 

Sir / Ma'am, 

It is my understanding that the EPA intends not to regulate the levels of Per chlorate in our drinking 

water. I urge you to reconsider this position. A standard must be set. Per chlorate is a harmful 

chemical that is used in rocket fuel and explosives. It should not be present in our children, or 

ourselves. Per chlorate affects the thyroid gland and may severely impair growth and development of 

fetuses and children. With this said, regulation is a must. This should not be allowed to go 

unmonitored. Please reconsider your position, for yourself, and our future. Thank you for your time 

and consideration. 

Respectfully yours, Linda E. Lozier 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 891 of 1099

Commenter Name: E. Breem 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2147 

EPA Comment ID: 22030 

EPA Comment Code: 6120 

 

Comment: November 10, 2008 

To U.S. EPA, 

Please keep perchlorate out of drinking water! 

Help protect our children from the harmful chemical! 

Thank you, E. Breem 103 Askewton Rd. Severna Park, MD 21146 

Response: See response to comment code 6120. 

Commenter Name: John Vernon 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2148 

EPA Comment ID: 22031 

EPA Comment Code: 6120 

 

Comment: 11/9/08 

To the EPA - 

I strongly urge reconsideration of the decision not to regulate perchlorate in drinking water. This is 

an important public health issue, regardless of the simple minded tree huggers. Feel free to have the 

new Administrator give me a call or drop me a line, any time. Keep up your good work! 

Sincerely, John Vernon 107 Askewton Rd. Severna Park, MD 21146 

Response: See response to comment code 6120. 

Commenter Name: Katie Milleker 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2149 

EPA Comment ID: 22032 

EPA Comment Code: 6120 

 

Comment: Katie Milleker 112A Askewton Rd. Severna Park, MD 21146 

Water Docket EPA Mailcode 2822T 1200 Pennsylvania Ave. Washington, D.C> 20460 

Re: Docket ID No. EPA-HQ-OW-2008-0692 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 892 of 1099

I am writing to implore you to overturn your decision regarding not regulating perchlorate in 

drinking water! I am a lifelong resident of Maryland and I am a holistic healthcare practitioner. 

Health and nutrition is a priority in my family and while I can control what we eat, I have always 

assumed we have safe and clean drinking water. Since I believe that perchlorate is a harmful 

chemical, it is the responsibility of the EPA to regulate specific levels of this chemical in our 

drinking water. By being proactive in this regard we shall avoid future health problems and save not 

only countless dollars for health care but more importantly, citizens health and well-being. 

Sincerely, Katie Milleker 

Response: See response to comment code 6120. 

Commenter Name: Nancy 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2150 

EPA Comment ID: 22034 

EPA Comment Code: 6120 

 

Comment: 11/11/08 

To the powers that be, 

I write as a concerned citizen regarding perchlorate contamination. I understand that it may be 

present in our water supply, especially near military installations. I live in Anne Arundel Country, 

Md. - home to Ft. Meade, as well as mercury contamination sites. And for 35 years, I have worked in 

the field of early childhood disabilities. 

Whatever control we may have over harmful substances in our environment is worth achieving. 

Please consider the safety cautions related to perchlorate contamination. 

Thank you Nancy [illegible] 

Response: See response to comment code 6120. 

Commenter Name: Taylor M. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2151 

EPA Comment ID: 22041 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

I believe that it is important to keep our water safe and healthy. Having perchlorate is not healthy at 

all. I'd rather not have my body damaged just because I drank some water. Please fix this problem! 

Thank you Taylor. M. [no surname] 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 893 of 1099

Commenter Name: Lewis W. Billups 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2152 

EPA Comment ID: 22044 

EPA Comment Code: 6120 

 

Comment: TO: EPA From: Lewis W. Billups 

To Whom It May Concern, 

As a citizen concerned about passing a stringent and decisive clean water act by congress, I request 

that you work with the organization Clean Water Action to ban the use of per chlorate. We as a 

nation should have access to clean and safe water without toxic chemicals. 

Respectfully, Lewis W. Billups 

Response: See response to comment code 6120. 

Commenter Name: George Cooper 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2153 

EPA Comment ID: 22045 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

I support imposing a standard on the regulation of perchlorate in drinking water. 

Sincerely, George Cooper 3612 Oval Dr Alexandria, VA 22305 

Response: See response to comment code 6120. 

Commenter Name: Laura Ricard 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2154 

EPA Comment ID: 22057 

EPA Comment Code: 6120 

 

Comment: To Whom It May Concern 

As a concerned citizen who cares deeply about environmental issues I urge you to list perchlorate as 

a chemical sufficiently toxic to limit its presence in drinking water. Given our recent change in 

leadership I am hopeful that you will feel emboldened to take a stronger stance to protect our 

environment. 

Regards, Laura Richard, PA C 516 Tennessee Ave Alexandria, VA 22305 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 894 of 1099

Response: See response to comment code 6120. 

Commenter Name: Sheila C Joy 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2155 

EPA Comment ID: 22070 

EPA Comment Code: 6120 

 

Comment: 11/17/08 

To: EPA Water Docket 

I am a Virginia voter, perchlorate is a dangerous chemical which should be regulated. It occurs in 37 

states and adversely affects children. 

Sincerely, Sheila C Joy 3418 Old Dominion Blvd Alex VA 22305 

Response: See response to comment code 6120. 

Commenter Name: Kelsey Ogburn 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2156 

EPA Comment ID: 22072 

EPA Comment Code: 6120 

 

Comment: 11/13/08 

EPA 

You must continue to regulate perchlorate in our drinking water. 

Please help! 

Kelsey Ogburn 805 Redwood Trail Crownsville MD 21032 

Response: See response to comment code 6120. 

Commenter Name: William J. Shaw 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2157 

EPA Comment ID: 22087 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

I urge you to regulate the amount of perchlorate in our drinking water supply. This issue is vital to 

our future. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 895 of 1099

Sincerely, William J. Shaw 299 Aston Forest Ln Crownsville, MD 21032 

Response: See response to comment code 6120. 

Commenter Name: J Savage 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2158 

EPA Comment ID: 22088 

EPA Comment Code: 6120 

 

Comment: Jomi Savage 

We don't want harmful chemicals in our drinking water! They serve no usefull purpose and only 

impair our well being. So please for god sake, STOP PUTTING THAT [expletive] IN OUR 

WATER!! 

Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Gary Elson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2159 

EPA Comment ID: 22089 

EPA Comment Code: 6120 

 

Comment: November 13, 2008 

Water Docket, EPA Mailcode 2822T 1200 Pennsylvania Avenue Washington, DC 20460 

Attn: Docket ID# EPA-HQ-OW-2008-0692 

I support the regulation of perchlorate in drinking water and the strict enforcement of its 

prohibition. Perchlorate contaminations is a nationwide problem and the protection of the public 

health requires such regulation on a nationwide basis. 

Gary Elson 409 Kyle Rd. Crownsville, MD 21032 

Response: See response to comment code 6120. 

Commenter Name: Elaine & George Anderson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2160 

EPA Comment ID: 22090 

EPA Comment Code: 6120 

 

Comment: 11/17/08 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 896 of 1099

To: EPA Water Docket, 

I am a Virginia voter, and a kayaker and interested in preserving our waters. Perchlorate is a 

dangerous chemical found in 37 states. Since it can get into water and children's thyroids are 

vulnerable, it needs to be regulated. 

Elaine Anderson George Anderson 

Response: See response to comment code 6120. 

Commenter Name: Molly J. Hall 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2163 

EPA Comment ID: 22093 

EPA Comment Code: 6120 

 

Comment: November 11, 2008 

Dear EPA, 

It is time you take the health and safety of our drinking water seriously. We need a federal law that 

will keep the chemical, perchlorate out of our drinking water. 

Please move swiftly on this matter. The health and safety of your constituents depends on your 

quick action. 

Molly J. Hall Arnold, MD 

Response: See response to comment code 6120. 

Commenter Name: Cather Pauly 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2164 

EPA Comment ID: 22094 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

From a concerned Virginia resident, as a hopeful mom to be, I urge you to reconsider your decision 

not to regulate perchlorates, which could potentially harm not only me and my pets, but also my 

future children. This is a serious matter for all of our health & welfare. Please help keep us safe. 

Thank you Cather Pauly 3108 Wellington Rd Alexandria VA 22302 

Response: See response to comment code 6120. 

Commenter Name: Teresa Avery 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 897 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-2165 

EPA Comment ID: 22095 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

I urge you to regulate the amount of perchlorate in our drinking water supply. 

Sincerely, Teresa Avery 1246 Timber Turn Arnold, Md. 21012 

Response: See response to comment code 6120. 

Commenter Name: Jean Sengelaub 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2166 

EPA Comment ID: 22096 

EPA Comment Code: 6120 

 

Comment: To: EPA 

I urge you to regulate the amount of perchlorate in our drinking water to a maximum of 2 ppb. 

Sincerely, Jean Sengelaub 1289 Terrace Lane Arnold, MD 21012 11-10-08 

Response: See response to comment code 6120. 

Commenter Name: Jean Sengelaub 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2166 

EPA Comment ID: 22097 

EPA Comment Code: 6120 

 

Comment: To: EPA 

I urge you to regulate the amount of perchlorate in our drinking water to a maximum of 2 ppb. 

Sincerely, Jean Sengelaub 1289 Terrace Lane Arnold, MD 21012 11-10-08 

Response: See response to comment code 6120. 

Commenter Name: Claire 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2167 

EPA Comment ID: 22098 

EPA Comment Code: 6120 

 

Comment: EPA, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 898 of 1099

We all should have drinking water free of substances like perchlorate. Please take another look at 

regulation. Its impact could be more harmful than we know now - affecting the thyroid gland. 

Thank you, Claire [illegible] 

Response: See response to comment code 6120. 

Commenter Name: Mark Milleker 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2168 

EPA Comment ID: 22099 

EPA Comment Code: 6120 

 

Comment: Mark Milleker 112 Askewton Rd Severna Park MD 21146 

Water Docket EPA Mailcode 2822T 1200 Pennsylvania Ave Washington, D.C. 20460 

November 10, 2008 

Re: Docket # EPA-HQ-OW-2008-0692 

Not allowing the EPA to regulate perchlorate in drinking water makes no sense. Hopefully the 

Obama administration will overturn all executive orders that harm our environment and the people 

that drink water. 

A national primary drinking water regulation is needed right away. Think of the cost savings we will 

achieve with a healthier population. 

Make the right choice. 

Mark Milleker Drinking Water Advocate 410 647-7264 

Response: See response to comment code 6120. 

Commenter Name: Jennifer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2169 

EPA Comment ID: 22100 

EPA Comment Code: 6120 

 

Comment: November 12, 2008 

Dear EPA, 

I urge you to seriously consider regulating perchlorate in drinking water. 

Sincerely, Jennifer [illegible] 211 St Andrews Road Severna Park, Md 21146 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 899 of 1099

Response: See response to comment code 6120. 

Commenter Name: Georgette A Irwin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2170 

EPA Comment ID: 22221 

EPA Comment Code: 6120 

 

Comment: November 20, 2008 

EPA - 

Please work to regulate or eliminate PERCHLORATE from all drinking water. 

Yours truly, Georgette A. Irwin 1044 Springhill Way Gambrills MD 21054 301-621-7881 

Response: See response to comment code 6120. 

Commenter Name: Bonita K Patterson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2171 

EPA Comment ID: 22228 

EPA Comment Code: 6120 

 

Comment: Nov. 20, 2008 

ATTN: EPA Water Docket 

I am writing to ask you to please regulate perchlorate in drinking water. 

This is a very harmful chemical and our water is already filled with plenty of other harmful 

chemicals. 

I have lived in our house for 38 yrs. and had breast cancer 10 yrs. ago. We stopped using tap water 

@ that time. We now use reverse osmosis water filters. 

I truly believe are water is one of the main reasons we have so much [illegible] in our development. 

Listen to the people crying out for safe drinking water. 

Bonita K. Patterson 867 Frost Valley Cir Gambrills, MD 

Response: See response to comment code 6120. 

Commenter Name: 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2173 

EPA Comment ID: 22252 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 900 of 1099

EPA Comment Code: 6120 

 

Comment: 11-6-08 

To whom it may concern, 

Drinking water should be tested for perchlorate because children and adults could be harmed by 

these chemicals. 

Thank you, (illegible) 

Response: See response to comment code 6120. 

Commenter Name: Rachelle Stanley 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2174 

EPA Comment ID: 22323 

EPA Comment Code: 6120 

 

Comment: Water Docket EPA Mail code 2822T 1200 Pennsylvania Avenue Washington, DC 

20460 

ATTN: Docket ID No: EPA-HQ-OW-2008-0692 

As someone who trusts the Government to protect me from "The Axis of Evil", I also trust that 

same Government to ensure I have safe, clean drinking water available to myself and my children. I 

recently learned that the EPA is intending to not regulate the amount of perchlorate in drinking 

water, and I find that frightening. 

I strongly encourage you to reconsider this decision; as it will affect my two young children. 

Perchlorate has been linked to mental retardation, loss of hearing and speech or deficits in motor 

skills in children with thyroid problems. My children are genetically predisposed to thyroid disease, 

so this is very worrisome for me. 

We have enough to worry about in this country: terrorism, education, health care, the economy, 

using less oil and reducing our carbon footprints. I don't want to have to worry about the water that 

crosses my children's lips too. 

Sincerely, Rachelle Stanley 2607 April Dawn Way Gambrills, MD 21054 

Response: See response to comment code 6120. 

Commenter Name: Kaii Heward 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2175 

EPA Comment ID: 22329 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 901 of 1099

Comment: 11/19/08 

Dear Fellow American, 

I am writing you concerning our water supply. Among all of the other contaminates in our drinking 

water, there is the issue of perchlorate and I hear the EPA does not intend to regulate this chemical. 

It is inconceivable to me that it is not already being monitored considering how it affects thyroids, 

motor skills, development and other kinds of mental health. It impacts our children the most. I feel 

that perchlorate should be part of the mandatory testing done for our water supply. The health of all 

American citizens is crucial. Basically, failure to remove perchlorate's effects is consciously 

neglectful. We need to lock after our own welfare and be our own advocates. Monies used to protect 

ourselves from this chemical are just that: Monies. Our health is priceless. Please vote to make the 

regulation of perchlorate mandatory for all states. 

Thank you for your time, 

Kaii Heward 

Response: See response to comment code 6120. 

Commenter Name: Carrie Allen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2176 

EPA Comment ID: 22330 

EPA Comment Code: 6120 

 

Comment: My family and I would like the EPA to continue to regulate Perchlorate levels in our 

water supply. We have read that it can negatively affect our health in low levels. 

Thank you Carrie Allen 2516 Vivaldi Ln Gambrills MD 21054 

Response: See response to comment code 6120. 

Commenter Name: Anna Hyde 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2177 

EPA Comment ID: 22331 

EPA Comment Code: 6120 

 

Comment: To whom it may concern: 

As a mother to be and the wife of a doctor, I am consistently troubled by what contaminants are 

contained in our drinking water, especially after several recent studies that have raised alarm. I urge 

you to reverse your decision and set a federal limit for perchlorate in drinking water. It can have 

disasterous health impacts, especially for infants and children. 

Sincerely, Anna Hyde 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 902 of 1099

Response: See response to comment code 6120. 

Commenter Name: Andrea Leidolf 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2178 

EPA Comment ID: 22332 

EPA Comment Code: 6120 

 

Comment: Nov 17, 2008 

Dear epa, 

I would like to see a limit set on perchlorate in drinking water. 

Sincerely, Andrea Leidolf 909 N Overlook Dr Alexandria VA 22305 

Response: See response to comment code 6120. 

Commenter Name: Harrison B. Williams 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2179 

EPA Comment ID: 22333 

EPA Comment Code: 6120 

 

Comment: To: the US Environmental Protection Agency 

I strongly urge you to reverse your decision to NOT regulate perchlorate in drinking water. Because 

perchlorate does not readily dissipate and can contaminant drinking water for years after it is 

released into the environment, I believe it is imperative that it be regulated by the EPA. 

Harrison B. Williams 3617 Oval Drive Alexandria, Va 22305 

Response: See response to comment code 6120. 

Commenter Name: Karl 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2180 

EPA Comment ID: 22334 

EPA Comment Code: 6120 

 

Comment: 11/12/08 

To All Concerned at the EPA: 

Please keep perchlorate out of our drinking water. 

If there are other solutions for getting rid of this please explore. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 903 of 1099

Thank you, Sincerely Karl Hutchinson 3761 Gunston Road Alexandria, VA 22302 

Response: See response to comment code 6120. 

Commenter Name: Kevin & Lita Yates 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2181 

EPA Comment ID: 22335 

EPA Comment Code: 6120 

 

Comment: November 18, 2008 

18801 Breeze Way Circle Olney, MD 20832 

To Whom It May Concern: 

We are very concerned about the EPA announcing its intention NOT to regulate perchlorate in 

drinking water. Perchlorate has been found in 37 states, and in public water systems serving over 20 

million people. As parents of three growing children, we are especially concerned about the presence 

of perchlorate in our drinking water since it is a harmful chemical that can impair the thyroid gland, 

which controls growth, development and metabolism. 

We need our government agencies to regulate harmful chemicals. This is the purpose of the EPA, to 

protect citizens from harmful pollution. Please protect the citizens of the United States by regulating 

the harmful chemical perchlorate in drinking water. 

Thank you, Kevin and Lita Yates 

Response: See response to comment ID 19873 under comment code 5220. 

Commenter Name: Hillary Collyer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2182 

EPA Comment ID: 22372 

EPA Comment Code: 6120 

 

Comment: 11/12/08 

Dear EPA, 

Perchlorate occurs widely. There are many sources of perchlorate contamination. Because there has 

not been routine testing, we do not know the full extent of contamination. I ask that you act quickly 

to perform appropriate tests and implement adequate regulation. 

Thank you for your attention to this important matter. 

Regards, Hillary Collyer 3775 Gunston Rd. Alexandria, VA 22302 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 904 of 1099

Response: See response to comment code 6120. 

Commenter Name: 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2183 

EPA Comment ID: 22377 

EPA Comment Code: 6120 

 

Comment: EPA Washington, DC 20005 

To Whom It May Concern: 

Please address the issue of perchlorate in our DC drinking water, and protect us from the problems 

that can occur from over exposure. It is to that end that I fully endorse the efforts of the Clean 

Water Action organization and their efforts to rid our drinking water of this dangerous and harmful 

chemical. 

Thank you for your interest in this matter. 

Sincerely (illegible) 3507 Nst NW Was., DC 20005 

Response: See response to comment code 6120. 

Commenter Name: M. Jane Schumacher 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2185 

EPA Comment ID: 22379 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Please regulate perchlorate because it impacts the health of children; fetuses, as well as adults. 

The regulation of this substance in our drinking water is very important to me and to all others who 

are aware of this. 

Please reconsider and make this an important regulation. 

Thank you, M. Jane Schumacher 

Response: See response to comment code 6120. 

Commenter Name: Tina Carroll 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2189 

EPA Comment ID: 22380 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 905 of 1099

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

I am a concerned citizen of Maryland. I have recently learned of your decision to choose not to 

regulate perchlorate levels in our drinking water. In Maryland we have several known facilities that 

distribute perchlorate: 

Aberdeen Proving Ground Alliant Tech Systems Naval Surface Warfare Center New Jersey 

Fireworks Thiokol Corporation 

Response: This is not a comment, no response needed. 

Commenter Name: Diego Bank 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2190 

EPA Comment ID: 22383 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

I hope that our drinking water contaminants can be regulated, so that people aren't affected by the 

negative effects of perchlorate. 

Thanks. 

Sincerely, Diego Bank Kingston 

Response: See response to comment code 6120. 

Commenter Name: Brenda Lewis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2191 

EPA Comment ID: 22390 

EPA Comment Code: 6120 

 

Comment: To All Readers, 

Perchlorate is a harmful chemical found in our drinking water. It is used in Rocket fuel and 

explosives. Every day, citizens ingest thousands of gallons nationally. If something is not done soon, 

This great country will be left a barren wasteland with no humans to care for it and all our efforts 

will have been wasted. Perchlorate can cause massive problems both physically and mentally to any 

human that ingests it. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 906 of 1099

Response: This is not a comment, no response necessary. 

Commenter Name: Brenda Lewis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2191 

EPA Comment ID: 22392 

EPA Comment Code: 6120 

 

Comment: This country strives not on its technological booms, but the minds that drive them. If 

we do not act now, it'll soon be too late and what use will these technological advances be to us 

then. Without the bright minds of our citizens, what use is a government who wouldn't act when it 

had the chance. 

If the EPA does not do something to prevent further problems now, then there is no point in 

allowing them to stay as a federal agency anymore. The EPA has a responsibility to act now and as 

such should proceed with all haste. No Bureaucratic procedure or code should stop them. No effort 

should be made to stop them from proceeding to fulfill their duty to this great country. 

There are many sources of perchlorate contamination including many military bases, fireworks 

manufacturers, and blasting at construction sites. If there were more routine testing then perhaps the 

problem could be more properly identified. Currently perchlorate has been found in 37 states, and in 

public water systems serving over 20 million people. 

Respectfully, Brenda Lewis 

Response: See response to comment code 6120. 

Commenter Name: James Kirk 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2192 

EPA Comment ID: 22399 

EPA Comment Code: 6120 

 

Comment: To whom it may concern: 

My family and I are greatly concerned that the EPA is considering not to regulate perchlorate in our 

drinking water. 

We fully support a national primary drinking water regulation to protect future generations. 

Thanks James Kirk 2482 Red Fall Ct Gambrills, MD 21054 

Response: See response to comment code 6120. 

Commenter Name: Leigh E 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2193 

EPA Comment ID: 22408 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 907 of 1099

EPA Comment Code: 6120 

 

Comment: 11-20-08 

Dear EPA 

If you are truly an agency that protects the environment you will understand that perchlorate 

contamination is a nationwide problem and that it has health impacts at lower levels than previously 

thought. 

Many people can not afford either bottle water or to filter their water. I have a thyroid problem. 

Could it be from drinking perchlorate? We need a national primary drinking water regulation to 

protect all of us. 

Sincerely Leigh E [illegible] 

Response: See response to comment code 6120. 

Commenter Name: Georgia 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2194 

EPA Comment ID: 22409 

EPA Comment Code: 6120 

 

Comment: Dear EPA Folks, 

Perchlorate in the water is a terrible thing for our nation's children, and to think it's allowed in the 

DC water is awful. Please think about regulating this! 

Thank you, Georgia [illegible] 3519 Prospect St NE Was., DC 2007 

Response: See response to comment code 6120. 

Commenter Name: Ben Richeda 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2204 

EPA Comment ID: 22410 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

Seriously, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 908 of 1099

The US has the best drinking water in the world. I should know, I've been around. However, 

implicit in this assumption is the trust that the EPA is doing a good job. Don't mess this up for the 

rest of us who can't afford bottled water or filters. 

Sincerely, Ben 

Sincerely, Ben Richeda 1160 Camino Cruz Blanca Santa Fe, NM 87505 

Response: See response to comment code 6120. 

Commenter Name: Sarah Beth Cassel 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2205 

EPA Comment ID: 22411 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

I think it is obvious to protect our future generations. My boyfriend is a father of a young one and 

and hope one day to be a mommy. I already have to worry about mercury levels in my fish... and 

now i have this to be concerned about. We are poisoning our earth and rightfully we are the ones 

paying for it, but protect the innocents. let us become a nation that is ecologically intelligent and 

looking into the future and no be so selfish. please. 

Again, I urge you to reverse your decision and to set a national drinking water standard for 

perchlorate. 

it is that important. 

Sincerely, 

Sarah Beth Cassel 115 N. Beechwood Ave. Catonsville, MD 21228 

Response: See response to comment code 6120. 

Commenter Name: Dixie Walker 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2210 

EPA Comment ID: 22412 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 909 of 1099

I urge you to set a drinking water standard for perchlorate. Perchlorate is found in drinking water in 

at least 26 states, and 20-40 million people could be exposed to this chemical. Businesses and 

Individuals appreciate "Standards" and "Standards for safe drinking water" is something the average 

U.S. citizen believes the EPA provides. They have no idea that the upmost is not being done to 

protect the countries supply of clean water. Do the right thing for the multitude of taxpayers who 

are busy making a living and raising a family. THEY TRUST that the EPA is looking out for their 

health - Honor their confidence in you by insuring that perchlorate is regulated throughout the 

U.S.A. 

I urge you to reverse your decision and to set a national drinking water standard for perchlorate. 

Sincerely, Dixie Walker 214 Chase Dr Pelham, AL 35124 

Response: See response to comment code 6120. 

Commenter Name: Anita Brightman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2211 

EPA Comment ID: 22413 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

I urge you to set a drinking water standard for perchlorate. I live near Aberdeen Proving Ground 

and have countless friends who suffer with thyroid disease. While working on Post, I too was 

diagnosed with thyroid problems and took synthroid for 10 years. Once I stopped drinking that 

water and changed jobs, I could not get my thyroid regulated. They eventually took me off the 

medicine because my thyroid function was in normal ranges. 

This is an important issue and warrants attention and more study. 

Sincerely, anita brightman 210 archer street bel air, MD 21014 

Response: See response to comment code 6120. 

Commenter Name: Andrea Link 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2216 

EPA Comment ID: 22415 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 910 of 1099

Dear Administrator Johnson and EPA staff, 

I am writing to urge you to keep out water clean. It should be mandated that toxic chemicals be kept 

out of our water. There should be no question about this subject. Why on earth would you even 

consider not taking care of the health of our people? 

Please keep our water clean. 

Sincerely, Andrea Link 4028 S. Delaware Englewood, CO 80110 

Response: This is not a comment, no response necessary. 

Commenter Name: Andy Burgess 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2217 

EPA Comment ID: 22416 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

I cannot believe you have decided not to set a drinking water standard for perchlorate that will 

protect pregnant women and babies nationwide. 

There is no excuse for this decision - no financial, statistical, or political rationale can offset the 

moral obligation you have to protect the citizens of the USA from dangerous exposure to chemicals 

we recognize and understand how to abate. 

Response: See response to comment code 6120. 

Commenter Name: Andy Burgess 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2217 

EPA Comment ID: 22418 

EPA Comment Code: 6120 

 

Comment: Again, I urge you to reverse your decision and to set a national drinking water standard 

for perchlorate. 

Sincerely, Andrew Burgess 2615 6th Street Boulder, CO 80304 

Response: See response to comment code 6120. 

Commenter Name: Neil and Pam Ackerman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2219 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 911 of 1099

EPA Comment ID: 22419 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

Keep perchlorate OUT of our drinking water, PLEASE! 

Sincerely, Neil and Pam Ackerman 8500 Falmouth Ave #3313 Beachport Complex Playa Del Rey, 

CA 90293-8727 

Response: See response to comment code 6120. 

Commenter Name: Amy Geffre 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2223 

EPA Comment ID: 22420 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

Hello. 

As a student of toxicology and a mother, I urge you to set a drinking water standard for perchlorate 

that will protect pregnant women and babies nationwide. I know you must already understand the 

potential health problems perchlorate can cause, so I will not lecture, but please take note of what I 

say. 

My son is just older than newborn; tap water goes into his formula and that of many other small 

children that I know and do not. Their nervous systems are fragile yet as they develop; when there is 

even the most minute chance of harming or stunting so precious a part of them, I feel that it is cause 

for strict, non-discriminate regulations to be put in place concerning such potentially harmful agents. 

"Perchlorate is found in drinking water in at least 26 states, and 20-40 million people could be 

exposed to this chemical." This statement worries me. I see my son developing, making cause-andeffect relationships, beginning to comprehend color, beginning to respond to me with smiles. It 

makes me feel fulfilled beyond anything else I've felt. I can't imagine how horrible it would be for a 

mother to look at her child and know that her baby couldn't do such things because of exposure to a 

harmful chemical. 

I am aware that the problem of this compound's presence in drinking water is not necessarily so bad 

as to cause such heavy retardation in a child, but I worry about the potential for the situation to fast 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 912 of 1099

become as such, thus I write to you to consider making a blanket regulation preemptively to ensure 

drinking water will never have harmful levels of perchlorate. 

Problems are best avoided by ensuring that they can't happen to begin with. Please consider this. I 

urge you to. Please reverse your decision and set a national standard on perchlorate. Children are 

depending on us to keep them safe and healthy. Let's not make them lose their faith in us. 

Sincerely, Amy Geffre 131 N Clark St Apt. B Forest City, IA 50436 

Response: See response to comment code 6120. 

Commenter Name: Kim Leerdam 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2224 

EPA Comment ID: 22421 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

Are you serioussssssssssss????????????????? 

Be logical. 

Again, I urge you to reverse your decision and to set a national drinking water standard for 

perchlorate. 

I hope Robert Kennedy Jr takes over the EPA and you all get fired for being so insincere. 

Sincerely, Kim Leerdam 410 N. Rossmore Ave #405 Los Angeles, CA 90004 

Response: See response to comment code 6120. 

Commenter Name: 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2226 

EPA Comment ID: 22422 

EPA Comment Code: 6120 

 

Comment: EPA Water Docket 

I am a student and I'm studying Biology. Perchlorate is a dangerous chemical and in the water. We 

need to protect children so it must be regulated. 

Sincerely, [illegible] 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 913 of 1099

1721 Crestwood Dr. Alexandria, Va 22302 

Response: See response to comment code 6120. 

Commenter Name: Malcolm Herstand 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2227 

EPA Comment ID: 22423 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

Please! 

Set a limit for perchlorate levels in water. 

Your report talks about doses over months. But people live and drink from their water supply for 

decades. 

Maximum levels would be enforceable by encouraging reduction and containment of perchlorate use 

in fireworks and battery manufacturing. 

As a hydrologist for Montana State, I understand that groundwater contamination is receiving 

increased attention, and citizens are becoming more educated about it. 

Don't become known as the 

Sincerely, Malcolm Herstand 1625 W. Kagy Bozeman, MT 59715 

Response: See response to comment code 6120. 

Commenter Name: Mary Miller 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2229 

EPA Comment ID: 22424 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

I urge you to reverse your decision and to set a national drinking water standard for perchlorate. 

Protecting our drinking water is becoming a greater problem, and it needs to be addressed. I believe 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 914 of 1099

we have an obligation to protect people, especially pregnant mothers and children from dangerous 

chemicals in the water. 

Thank you. 

Sincerely, Mary Miller 417 Akers Drive Wilmore, KY 40390 

Response: See response to comment code 6120. 

Commenter Name: Marie Maccabee 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2240 

EPA Comment ID: 22425 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

I urge you to set a drinking water standard for perchlorate that will protect life here on earth. I think 

it is necessary for your agency to set a national standard that is based on the best available science 

and that will protect public health. It would be litterally insane and completely unhuman for this 

group of yours to ignore your own staff scientists' reasonings about the dangers of this chemical. 

Contrary to your claims, protecting the health of young children is indeed a "meaningful opportunity 

for health risk reduction." 

Again, I urge you to reverse your decision and to set a national drinking water standard for 

perchlorate. 

Sincerely, marie maccabee 103 woodside ave thurmont, MD 21788 

Response: See response to comment code 6120. 

Commenter Name: Tigris Powers 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2244 

EPA Comment ID: 22426 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

Perchlorate should NOT be anywhere near our nation's pregnant women, infants, children, or our 

drinking water supply. It's difficult to believe that this is an issue that has to be questioned, when it 

poses a health threat to to 20-40 million people nation wide. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 915 of 1099

When the health of young children is being put to the test, aren't we better off being SAFE than 

sorry? 

Perchlorate poses a risk for pregnant women, newborns and young children by interfering with 

thyroid hormone, which is critical for optimal development of the brain and nervous system. 

Today 1 in 159 children are diagnosed with autism, a disorder that is directly related to the brain and 

nervous system. Could there be a connection? Is it worth risking? I don't think so. 

Response: See response to comment code 6120. 

Commenter Name: Rose Lernberg 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2246 

EPA Comment ID: 22428 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

Please reverse your decision and set a national drinking water standard for perchlorate that will 

protect pregnant women and babies nationwide. 

Perchlorate interferes with the thyroid hormone, which is critical for optimal development of the 

brain and nervous system. it is present in drinking water in at least 26 states, and 20-40 million 

people could be exposed to this chemical. This especially poses a risk for pregnant women, 

newborns and young children. 

It is urgent that you set a national standard, based on the best available science, to protect public 

health. Several states have set standards or guidelines for perchlorate, but these vary widely. Your 

own staff scientists say that not regulating perchlorate means some infants and young children will 

receive unsafe levels of exposure. The current draft scientific analysis should undergo independent 

scientific peer review and be used as the basis for the regulation. 

All Americans deserve healthy and clean drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anna Kovach 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2247 

EPA Comment ID: 22476 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 916 of 1099

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

I currently am working for a State Assemblywoman in New York. I have recently been doing alot of 

research about what goes into public drinking water, namely pharmecuticals. Along with these, 

which affect everything from microbacterium to small fish and amphibians, there are also a whole 

slew of chemicals from everywhere else too. Please make sure you regulate what goes into the water. 

I don't want anything worse to happen to my planet!!! 

I urge you to set a drinking water standard for perchlorate that will protect pregnant women and 

babies nationwide. Perchlorate poses a risk for pregnant women, newborns and young children by 

interfering with thyroid hormone, which is critical for optimal development of the brain and nervous 

system. Perchlorate is found in drinking water in at least 26 states, and 20-40 million people could be 

exposed to this chemical. 

Again, I urge you to reverse your decision and to set a national drinking water standard for 

perchlorate. 

Sincerely, Anna Kovach 124 Prospect Ave Apt 5 Binghamton, NY 13901 

Response: See response to comment code 6120. 

Commenter Name: Roman Berka 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2249 

EPA Comment ID: 22477 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

Thanks for doing nothing about perchlorate - great job. 

Signed, The American People 

Sincerely, Roman Berka 1260 Hillside Vw Algonquin, IL 60102 

Response: This is not a comment, no response necessary. 

Commenter Name: Rhona Schwartz 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2251 

EPA Comment ID: 22478 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 917 of 1099

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

For heaven's sakes, don't we have enough trouble with our imported food supply! What the heck is 

perchlorate doing in our water! 

You're supposed to help keep Americans safe. Get perchlorate banned and banished before all hell 

breaks loose. 

Sincerely, Rhona Schwartz 315 First Ave. W., #210 Seattle, WA 98119 

Response: See response to comment code 6120. 

Commenter Name: William McGhee 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2266 

EPA Comment ID: 22479 

EPA Comment Code: 6120 

 

Comment: WILLIAM MCGHEE 5 ROSENEATH COURT OLNEY MD 20832 

U.S. ENVIROMENTAL PROTECTION AGENCY 

E.P.A. Please take time to reconsiders the announced intention not to regulate per chlorate into our 

water system. I personally think this could provide a problem not only to my self but also to my 

children and my neighbors children. I did grow up in a time when you could drink from a water 

hose, but it was from a well. I have had the problem with broken water lines pollute our water 

system enough, to make me want to pop a well in the city. Please look at all options to regulate my 

and my families drinking water, for the future of my children and yours. 

Thank You, William Mcghee 

Response: See response to comment code 6120. 

Commenter Name: T., Craig, Sophie & Ian Brouillette 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2268 

EPA Comment ID: 22480 

EPA Comment Code: 6120 

 

Comment: November 24, 2008 

To the EPA: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 918 of 1099

As a mother of two small children and a firm advocate of drinking plenty of water every day, my 

family and I are deeply disturbed to hear that the EPA has decided NOT to regulate perchlorate in 

our drinking water. 

Perchlorate contamination is a nationwide problem that must be addressed and remedied. The 

effects of unsafe levels of perchlorate on the thyroid gland currently known that can have adverse 

impacts on health are devastating. 

We want the EPA to regulate perchlorate levels in our drinking water, and a Nation primary 

drinking water regulation is needed. 

Sincerely, The Brouillette Family of Maryland [illegible] Craig Sophie Ian 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2269 

EPA Comment ID: 22481 

EPA Comment Code: 6120 

 

Comment: EPA, 

I don't think I have to highlight the importance of the environment and the effect it has on people 

and more important children and animals, so I write this letter to illustrate my passion for the 

welfare and health of all human when I say please lets learn from the past of ignorance and please 

test and regulate Perchlorate. 

Respectfully, Concerned Citizen 

Response: See response to comment code 6120. 

Commenter Name: Glenn M. Phillips 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2270 

EPA Comment ID: 22482 

EPA Comment Code: 6120 

 

Comment: November 24, 2008 

Glenn M. Phillips 7778 Kidwell Dr. Hanover, MD 21076 

Water Docket, EPA Mailcode 2822T 1200 Pennsylvania Ave. Washington, DC 20460 

ATTN: Docket ID No. EPA-HQ-OW-2008-0692 

To whom it may concern, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 919 of 1099

Perchlorate is harmful and needs to be regulated in our water supply. This is a nation-wide problem 

and carries health impacts to everyone. Please review your choice not to regulate perchlorate in 

drinking water and amend your decision, as is only proper. 

Sincerely, Glenn M. Phillips 

Response: See response to comment code 6120. 

Commenter Name: Debbie 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2274 

EPA Comment ID: 22483 

EPA Comment Code: 6120 

 

Comment: Dear EPA: 

Perchlorate is harmful and needs to be tested in our water. Please take action to resolve the matter. 

Debbie [illegible] 788 Sunny Chapel Rd Odento Md 21113 

Response: See response to comment code 6120. 

Commenter Name: Mary Ogburn 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2275 

EPA Comment ID: 22484 

EPA Comment Code: 6120 

 

Comment: 11/13/08 

EPA 

You must continue to regulate perchlorate in our drinking water. Please help. 

Mary Ogburn 805 Redwood Trail Crownsville MD 21032 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2276 

EPA Comment ID: 22485 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Please regulate our drinking water. Help us keep our water safe and clean. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 920 of 1099

Response: See response to comment code 6120. 

Commenter Name: Jessica Gillengerten 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2277 

EPA Comment ID: 22486 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

hello. 

i am curious about this disinterest in regulating national drinking water. 

why wouldn't we want to continue to maintain healthy standards for our primary necessity in life? 

i spent many years in quebec, and enjoyed the benefit of seeing the true sources of the water 

supplies to their entire city. 

it's remarkable to note the difference, between florida sulphur water... carolina mountain water... 

new york city tap water... chicgao re-filtered lake michigan water...hawaiian lava rock filtered water, 

and canadian melted snow. 

of course there are geographic differences that create natural filtration variances, but why should we 

be sacrificing anything when it comes to keeping our water clean? 

we are capable of doing great things. we have boundless technology, and plenty of educated people 

looking to work... 

why not set a noble task, and pursue excellent standards? 

Perchlorate does not sound like a natural part of H20. and since my tap water does not come with a 

list of ingredients, save for a once a year particulate analysis, i would really prefer to know the EPA 

was doing a fine job keeping an eye on what was coming into my glass. 

the japanese are doing incredible things with water filtration. and as i have said, i was also very 

impressed with the great effort the canadians have put into protecting the pristine sources of their 

drinking water. 

why shouldn't we take pride in a precious commodity? last i heard, it was a costly item in jordan, 

where people were standing in line to get a limited amount of clean bottled water issued to them. 

and we painfully pollute, and waste...when we have the ability to improve. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 921 of 1099

again, I urge you to reverse your decision and to set a national drinking water standard for 

perchlorate, and to raise our standards overall. 

clean water is a deciding factor for where i choose to live in this world. it's amazing to think that it is 

something the EPA could possibly be taking for granted. thank you. 

Sincerely, jessica gillengerten 3407 gerhardt st sarasota, FL 34237 

Response: See response to comment code 6120. 

Commenter Name: Linda Yow 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2293 

EPA Comment ID: 22488 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

Please set a protective drinking water standard for perchlorate as required by the Safe Drinking 

Water Act, reversing EPA's preliminary regulatory determination and doing what is right. Our food 

and water supplies are widely polluted with perchlorate and its toxic effects are well known, so 

action on this problem is urgent. 

Exposure to perchlorate in the U.S. population exceeds the reference dose set by EPA, so EPA 

needs to incorporate the protective methodology for the sake of the millions of U.S. families 

exposed to dangerous levels of perchlorate contamination. 

Thank you for your attention. 

Sincerely, Linda Yow Route 1 Box 1650 Glen Allen, MO 63751 

Response: See response to comment code 6120. 

Commenter Name: James Pierson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2296 

EPA Comment ID: 24977 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 922 of 1099

For the good of our country, it is critical for the EPA to set national standards, based on the best 

available science, to protect public health. The EPA's scientists have determined that your decision 

not to regulate perchlorate places some infants and young children above safe levels of exposure. 

The EPA's current draft scientific analysis should undergo independent scientific peer review and 

should be used as the basis for regulations relative to perchlorate. 

I urge you to reverse your decision and to set a national drinking water standard for perchlorate. 

Sincerely, James Pierson 1079 Yorktown Drive Charleston, SC 29412 

Response: The Agency believes that further review by the National Research Council would 

unnecessarily delay regulatory decision making for perchlorate. Therefore, EPA is not, at present, 

planning to request additional NRC review of issues related to perchlorate. Instead, EPA is issued a 

notice in August of 2009 seeking comments on a broad range of alternative approaches to the 

interpretation of the scientific data relevant to a regulatory determination for perchlorate in drinking 

water. 

EPA has determined to regulate perchlorate in drinking water. See response to comment code 6120. 

Commenter Name: Kraig Erickson 

Commenter Organization: RMC Water and Environment (RMC) 

EPA Document ID: EPA-HQ-OW-2008-0692-2299 

EPA Comment ID: 24978 

EPA Comment Code: 6120 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

I urge you to set a drinking water standard for perchlorate that will protect pregnant women and 

babies nationwide. Perchlorate poses a risk for pregnant women, newborns and young children by 

interfering with thyroid hormone, which is critical for optimal development of the brain and nervous 

system. Perchlorate is found in drinking water in at least 26 states, and 20-40 million people could be 

exposed to this chemical. 

Several states have set drinking water standards or guidelines for this chemical, but these standards 

vary widely, so it is critical for the EPA to set a national standard that is based on the best available 

science and that will protect public health. The EPA's own staff scientists have determined that your 

decision not to regulate perchlorate places some infants and young children above safe levels of 

exposure. The EPA's current draft scientific analysis should undergo independent scientific peer 

review and should be used as the basis for the regulation. 

Response: The Agency believes that further review by the National Research Council would 

unnecessarily delay regulatory decision making for perchlorate. Therefore, EPA is not, at present, 

planning to request additional NRC review of issues related to perchlorate. Instead, EPA is issued a 

notice in August of 2009 seeking comments on a broad range of alternative approaches to the 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 923 of 1099

interpretation of the scientific data relevant to a regulatory determination for perchlorate in drinking 

water. 

EPA has determined to regulate perchlorate in drinking water. See response to comment code 6120. 

Commenter Name: Roland 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2300 

EPA Comment ID: 24981 

EPA Comment Code: 6120 

 

Comment: Dear EPA 

Please regulate perchlorate. This is harmful to our drinking water. 

Roland [illegible] 16 W. [illegible] Ave Alexandria, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: J. Elizabeth Callis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2301 

EPA Comment ID: 24982 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Please regulate perchlorate 

Thank you for paying attention 

J Elizabeth Callis 19 W. Caton Ave. Alexandria, VA. 22301 

Response: See response to comment code 6120. 

Commenter Name: 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2302 

EPA Comment ID: 24983 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Please regulate perchlorate! 

[illegible] 437 E Luray Ave Alexandria, VA 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 924 of 1099

Commenter Name: Shannon O'Donnell 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2303 

EPA Comment ID: 24984 

EPA Comment Code: 6120 

 

Comment: DEAR EPA, 

PLEASE REGULATE PERCHLORATE & TOXINS. IT CAUSES BIRTH DEFECTS AND IT 

IS SOMETHING THAT CONCERNS ME. 

SINCERELY, SHANNON O'DONNELL 

Response: See response to comment code 6120. 

Commenter Name: 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2304 

EPA Comment ID: 24985 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Please regulate perchlorate in our water system. It is harmful to children and pregnant women. 

Sincerely, [illegible] 2406 Sanford St. Alexandria, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Daisy and G. Hickson Howell 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2305 

EPA Comment ID: 24986 

EPA Comment Code: 6120 

 

Comment: Dear Epa Water Docket 

- please regulate perchlorate that harmful to children. 

Daisy Howell G. Hickson 612 N [illegible] St Alexandria VA 

Response: See response to comment code 6120. 

Commenter Name: John 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2306 

EPA Comment ID: 24987 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 925 of 1099

EPA Comment Code: 6120 

 

Comment: Dear EPA Water Docket, 

Please regulate perchlorate. 

Thanks, 

John [illegible] 

Response: See response to comment code 6120. 

Commenter Name: Heidi Mayor 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2307 

EPA Comment ID: 24988 

EPA Comment Code: 6120 

 

Comment: 3614 Jenifer St., NW Washington, DC 20015 November 21, 2008 

Water Docket, EPA, Mailcode 2822T 1200 Pennsylvania Ave., NW Washington, DC 20460 

Re: Docket ID No. EPA-HQ-OW-2008-0692 

Dear Environmental Protection Agency: 

I am writing to urge, beg and even cajole you to set a federal limit for percholate in drinking water. 

Percholate is a nationwide probmem with significant health impacts. While I am fortunate enough to 

be able to afford to pay money to filter my drinking water, I believe that clean drinking water is a 

fundamental right of every American, including those who cannot afford to spend extra money to 

obtain it. Please regulate percholate. We will be a healthier, wealthier and wiser nation for your 

efforts. 

With kind regards, Heidi Mayor 

Response: See response to comment code 6120. 

Commenter Name: C. Foni Bissessar 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2308 

EPA Comment ID: 24989 

EPA Comment Code: 6120 

 

Comment: Please regulate perchlorate It's harmful to children and the environment 

C. Foni Bissessar 610 N. Ripley St. Alexandria, VA 22304 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 926 of 1099

Commenter Name: Cam Schaedel 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2309 

EPA Comment ID: 24990 

EPA Comment Code: 6120 

 

Comment: Dear EPA 

Please regulate perchlorate to keep our water safe for children. 

Sincerely, Cam Schaedel 5336 Thayer Ave. Alexandria, VA 22304 

Response: See response to comment code 6120. 

Commenter Name: Jeremiah Marsh 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2311 

EPA Comment ID: 24992 

EPA Comment Code: 6120 

 

Comment: EPA Water Docket 

Please regulate perchlorate, it harms kids in development. 

Jeremiah Marsh Medical School Student Howard University 

Response: See response to comment code 6120. 

Commenter Name: Caroline Schaffer 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2312 

EPA Comment ID: 24994 

EPA Comment Code: 6120 

 

Comment: November 24, 2008 

Dear EPA Water docket 

Please regulate perchlorate. It harms childrens development. 

Caroline Schaffer 5347 Holms Run Parkway Alexandria VA 22304 

Response: See response to comment code 6120. 

Commenter Name: Thomas Blackwood 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2313 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 927 of 1099

EPA Comment ID: 24995 

EPA Comment Code: 6120 

 

Comment: 11/21/08 

EPA Water Docket 

I am a virginia fisherman/voter and wish to declare perchlorate as a dangerous chemical with 

negative health effects, especially for children. Since it is widespread and gets into water it should be 

regulated. 

Thomas Blackwood 801 Ramsey St Alex VA 22301 

Response: See response to comment code 6120. 

Commenter Name: David 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2314 

EPA Comment ID: 24996 

EPA Comment Code: 6120 

 

Comment: 11/24/08 

To EPA water docket 

I'm a Virginia voter and supporter of Virginia environment. Perchlorate is a dangerous chemical 

found in thirty seven states and affects the health of children. Since it gets into water we must call 

for it to be regulated. 

Sincerely, David [illegible] 4909 Rutland Pl. Alexandria, VA 22304 

Response: See response to comment code 6120. 

Commenter Name: Melanie 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2315 

EPA Comment ID: 24997 

EPA Comment Code: 6120 

 

Comment: As a concerned member of our area & a voter I wish to see that perchlorate be 

regulated because it gets into water supplies & has negative health effects, especially for children. 

Sincerely, Melanie [illegible] 602 [illegible] St. Alexandria VA 22308 

Response: See response to comment code 6120. 

Commenter Name: Robert A. 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 928 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-2316 

EPA Comment ID: 24998 

EPA Comment Code: 6120 

 

Comment: 11/20/08 

EPA Water Docket 

I am a long term Virginia resident. Perchlorate is a dangerous chemical. Since it gets into water & 

harms children, it should be regulated. 

Robert A. [illegible] 406 Highland Pl Alexandria, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: David Uhl 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2317 

EPA Comment ID: 24999 

EPA Comment Code: 6120 

 

Comment: 11/20/2008 David Uhl 

Water Docket, EPA, Mailcode 2822T 1200 Penn. Ave NW Docket ID No. EPA-HQ-OW-2008-

0692 

To whom it may concern: 

Given our current problems with deregulation, I urge the EPA to reverse its decision and set a 

federal limit for perchlorate in drinking water. 

Sincerely David Uhl, MPA 

Response: See response to comment code 6120. 

Commenter Name: Under 13 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2318 

EPA Comment ID: 25000 

EPA Comment Code: 6120 

 

Comment: Dear EPA 

I would like it if you find a better way to clean the water and not harm it or other people. I wish you 

take this in consideration. We need at least one good thing to happen in the world right now. Start 

by removing perchlorate water. 

(p.s. why are you trying to clean the water this way?) (good luck) 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 929 of 1099

[comment from patron under the age of 13] 

Response: See response to comment code 6120. 

Commenter Name: Under 13 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2319 

EPA Comment ID: 25001 

EPA Comment Code: 6120 

 

Comment: To whom it may concern, 

I learned there is a horrible chemical in our world. This chemical is called Perchlorate. Perchlorate 

can affect the thyroid gland, which controls growth, development and metabolism. This is very 

harmful to children and babies. This chemical has been found in 37 states. Therefore, WE NEED 

TO KEEP PERCHLORATE OUT OF DRINKING WATER!!!!!! Please help us keep our water 

safe by keeping Perchlorate out of our drinking water! 

Sincerely, [comment from patron under the age of 13] 

Response: See response to comment code 6120. 

Commenter Name: Under 13 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2321 

EPA Comment ID: 25002 

EPA Comment Code: 6120 

 

Comment: To Whom it may concern: 

I learned that chemicals are in our water. I want to grow up healthy and strong so can you please 

make a law to keep perchlorate out of our water. 

from, [comment from patron under the age of 13] 

Hi there Girls Rule! 

Response: See response to comment code 6120. 

Commenter Name: Under 13 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2322 

EPA Comment ID: 25003 

EPA Comment Code: 6120 

 

Comment: Water Docket EPA Mail code 2822T 1200 Pennsylvania Avenue Washington, DC 

20460 ATTN: Docket ID No: EPA-HQ-OW-2008-0692 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 930 of 1099

My name is [comment from patron under the age of 13]. I am six. I want to drink clean water. My 

mom says I should write to you to tell you test for Perchlorate. She's usually right about that kind of 

stuff. Please reconsider your decision to not test for Perchlorate. My future depends on it. 

Thank you, [comment from patron under the age of 13] 

Response: See response to comment code 6120. 

Commenter Name: Under 13 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2323 

EPA Comment ID: 25004 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

I think it is inportant to have clean water. Perchlorate should be filterd because it can inpair the 

thyroid gland. The thyroid gland controls groth, develope ment and metabolism. These prodlems are 

most likely to occur in kids like me. Please help us Fix this prodlem. 

Thank you 

Sincerely, [comment from patron under the age of 13] 

Response: See response to comment code 6120. 

Commenter Name: Under 13 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2324 

EPA Comment ID: 25005 

EPA Comment Code: 6120 

 

Comment: Date 11/0/08 

Dear EPA, 

Please pass laws to keep perchlorate contamination out of our water. This is drinking water so we 

want to keep it clean. We don't want kids, parents, or babys to get sick. Also we don't want it to 

come to our water because we don't want our people to get sick too. So lets all try to keep our water 

CLEAN and save the people. 

from, [comment from patron under the age of 13] 

Response: See response to comment code 6120. 

Commenter Name: Under 13 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 931 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-2325 

EPA Comment ID: 25006 

EPA Comment Code: 6120 

 

Comment: November 21, 2008 [comment from patron under the age of 13] 

Water Docket, EPA, Mailcode 2822T 1200 Pennsylvania Ave. NW Washington Dc 20460 Docket 

ID No. EPA-HQ-OW-2008-0692 

To Whom It May Concern: 

Please reverse your decision and set a federal limit for perchlorate in our drinking water. I may just 

be an 11 year old but I have a lot of years of water in my future so please protect my health and that 

of my families. Remember you drink and use this water too! 

Kindly, [comment from patron under the age of 13] 

Response: See response to comment code 6120. 

Commenter Name: Under 13 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2326 

EPA Comment ID: 25007 

EPA Comment Code: 6120 

 

Comment: 11/24/2008 [comment from patron under the age of 13] 

 To Whom it May Concern: 

I urge you to reverse your decision and set a federal limit for perchlorate in drinking water. 

Perchlorate is a nationwide problem and has health impacts at lower levels than previously thought. 

Please protect public health, especially infants and children, by regulating perchlorate. 

Sincerely, [comment from patron under the age of 13] 

Response: See response to comment code 6120. 

Commenter Name: Donna 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2328 

EPA Comment ID: 25008 

EPA Comment Code: 6120 

 

Comment: 11/19/2008 

To: EPA Water Docket 

I am a Virginia voter and work supporting environmental organizations and issues. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 932 of 1099

Perchlorate is a dangerous chemical and is widespread in water supplies with especially negative 

effects in children. Therefore it is extremely important to see that it is regulated. 

Sincerely, Donna [illegible] [illegible] W [illegible] Avenue Alexandria, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: R. Travers 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2330 

EPA Comment ID: 25010 

EPA Comment Code: 6120 

 

Comment: To EPA Water Docket 

Please regulate perchlorate, it is harmful to most living things and doesn't belong in water. 

R. Travers 432 E Luray Ave Alex. Va 22301 

Response: See response to comment code 6120. 

Commenter Name: Carl Wall 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2331 

EPA Comment ID: 25011 

EPA Comment Code: 6120 

 

Comment: Attention EPA Water Docket, 

I am extremely unhappy with the fact that perchlorate is an unregulated substance which pops up in 

water. This stuff can hurt children and in today's world we need to raise healthy Americans. Action 

needs to be taken so our country has safe standards. 

Thanks, Carl Wall 513 E [illegible] Alex. VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Emerson Tom 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2332 

EPA Comment ID: 25012 

EPA Comment Code: 6120 

 

Comment: November 21, 2008 Emerso Tom 3615 Ingomar Place, NW Washington DC 20015 

Water Docket, EPA, Mailcode 2822T 1200 Pennsylvania Ave. NW Washington Dc 20460 Docket 

ID No. EPA-HQ-OW-2008-0692 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 933 of 1099

To Whom It May Concern: 

Please reverse your decision and set a federal limit for perchlorate in our drinking water. I may just 

be a 13 year old but water is important to me and everyone I know. Please protect my health and 

that of my family. Remember you drink and use this water too! 

Kindly, Emerson Tom 

Response: See response to comment code 6120. 

Commenter Name: Michelle 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2333 

EPA Comment ID: 25013 

EPA Comment Code: 6120 

 

Comment: Dear EPA Water Docket 

Please regulate perchlorate in our water systems. The DoD already has a substitute to keep rockets 

flying. 

Regards Michelle [illegible] 542 E [illegible] Ave Alexandria, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Tracie 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2334 

EPA Comment ID: 25014 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Please regulate toxins from rocket fuel. They are harmful to children. 

Thanks, Tracie [illegible] 

Response: See response to comment code 6120. 

Commenter Name: Dennis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2335 

EPA Comment ID: 25015 

EPA Comment Code: 6120 

 

Comment: Nov. 20, 2008 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 934 of 1099

Water Docket, EPA, Mailcode 2822T 1200 Pennsylvania Av, NW Washington, DC 20460 Docket 

ID No. EPA-HQ-OW-2008-0692 

To whom it may concern: 

Please reverse your recent decision on perchlorate in drinking water by setting a federal limit. 

Perchlorate is a national problem that requires a Federal solution. 

Sincerely, Dennis Stout 

Response: See response to comment code 6120. 

Commenter Name: M.L. Lang 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2336 

EPA Comment ID: 25016 

EPA Comment Code: 6120 

 

Comment: To EPA 

Regards perchlorate - absolutely not to be dumped in our waters. Please encourage known substitute 

for rocket fuel. 

M.L. Lang 14 W. Rosemont Ave. 

Response: Perchlorate is not being dumped into our waters. 

Commenter Name: Under 13 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2338 

EPA Comment ID: 25018 

EPA Comment Code: 6120 

 

Comment: 11/24/2008 [comment from patron under the age of 13] 

 To Whom it May Concern: 

I urge you to reverse your decision and set a federal limit for perchlorate in drinking water. 

Perchlorate is a nationwide problem and has health impacts at lower levels than previously thought. 

Please protect public health, especially infants and children, by regulating perchlorate. 

Sincerely, [comment from patron under the age of 13] 

Response: See response to comment code 6120. 

Commenter Name: Under 13 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 935 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-2339 

EPA Comment ID: 25019 

EPA Comment Code: 6120 

 

Comment: Dear E.P.A, 

I want clean drinking water. Please help all states provide their citizens with clean drinking water. I 

don't want people getting sick. 

Sincerely, [comment from patron under the age of 13] 

Response: See response to comment code 6120. 

Commenter Name: Under 13 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2340 

EPA Comment ID: 25020 

EPA Comment Code: 6120 

 

Comment: To Whom it may concern 

There are bad chemicals in our water. Please make a law that keeps perchlorate out of the water so 

we can grow up healthy and strong. 

From [comment from patron under the age of 13] 

Response: See response to comment code 6120. 

Commenter Name: Under 13 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2320 

EPA Comment ID: 25036 

EPA Comment Code: 6120 

 

Comment: Water Docket EPA Mail code 2822T 1200 Pennsylvania Avenue Washington, DC 

20460 ATTN: Docket ID No: EPA-HQ-OW-2008-0692 

My name is [comment from patron under the age of 13] and I am three. I want to drink clean water 

just like my brother. My mom says I should write to you to tell you test for Perchlorate. She's usually 

right about that kind of stuff. Please reconsider your decision to not test for Perchlorate. My future 

depends on it. 

[comment from patron under the age of 13] 

Response: See response to comment code 6120. 

Commenter Name: Olivia Butler 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 936 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-2329 

EPA Comment ID: 25037 

EPA Comment Code: 6120 

 

Comment: Dear EPA Water Docket 

Please regulate perchlorate it's harmful to children, and can be replaced with other chemicals for 

rocket fuel. 

Olivia Butler 423 E Juray Ave Alexandria, Va. 22301 

Response: See response to comment code 6120. 

Commenter Name: T.C. Nelson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2341 

EPA Comment ID: 25038 

EPA Comment Code: 6120 

 

Comment: Dear EPA 

Please regulate perchlorate - it is dangerous to our family and future 

Sincerely, T.C. Nelson 15 W. [illegible] Alexandria VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Julia Goldstein 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2342 

EPA Comment ID: 25039 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Perchlorate is bad for people to consume. Limits should be set on how much is in our drinking 

water source. 

Julia Goldstein 4201 Massachusetts Ave, NW 8008E Washington, DC 20016 

Response: See response to comment code 6120. 

Commenter Name: Diane Millard 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2343 

EPA Comment ID: 25040 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 937 of 1099

Comment: Diane Millard 3503 Valley Dr. Alexandria, VA 22302 

Dear EPA; 

Please ban/regulate perchlorates in the drinking water in the DC/Northern VA area. These 

chemicals have been proven to cause disabilities in children, specifically affecting the thyroid. 

Please take the action to rid this toxic pollutant from our water and environment. I and generations 

to follow will greatly appreciate that action be taken now. 

Sincerely, Diane Millard 

Response: See response to comment code 6120. 

Commenter Name: JoAnn Tom 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2344 

EPA Comment ID: 25041 

EPA Comment Code: 6120 

 

Comment: November 21, 2008 JoAnn Tom 3615 Ingomar Place, NW Washington DC 20015 

Water Docket, EPA, Mailcode 2822T 1200 Pennsylvania Ave. NW Washington Dc 20460 Docket 

ID No. EPA-HQ-OW-2008-0692 

To Whom It May Concern: 

Please reverse your decision and set a federal limit for perchlorate in our drinking water. Please 

protect our health and that of our families. Remember you drink and use this water too! 

Kindly, JoAnn Tom 

Response: See response to comment code 6120. 

Commenter Name: Joan Kennan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2345 

EPA Comment ID: 25042 

EPA Comment Code: 6120 

 

Comment: November 10, 2008 

Water Docket, EPA Mailcode 2822T 1200 Pennsylvania Ave. Washington, DC 20460 

ATTN: Docket ID No. EPA-HO-OW-2008-0692 

In reference to EPA's intention not to regulate perchlorate in drinking water, I urge you to 

reconsider this position: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 938 of 1099

Perchlorate can impair the thyroid gland which controls growth, development and metabolism. 

These impacts are especially harmful to children and fetuses. 

I do believe that a national primary drinking water regulation is needed to protect public health. 

Sincerely, Joan Kennan 3143 O Street, NW Washington, DC 20007 

Response: See response to comment code 6120. 

Commenter Name: Teresa Kelley 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2346 

EPA Comment ID: 25043 

EPA Comment Code: 6120 

 

Comment: To whom it may concern, 

I am writing to keep perchlorate out of my drinking water. 

This is a problem for everybody including elderly, children and pets, also it can cause problems for 

people taking medications, like my family. 

Please take this letter into consideration when you vote on this subject. 

Thank you, Teresa Kelley 3109 Holly St. Alexandria, VA 22305 

Response: See response to comment code 6120. 

Commenter Name: Deborah Classman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2347 

EPA Comment ID: 25044 

EPA Comment Code: 6120 

 

Comment: To: Water Docket, EPA, Mailcode 2822T 1200 Penn. Ave NW Washington DC 20460 

Docket ID No EPA-HQ-OW-2008-0692 

From: Deborah Classman 5240 Nebraska Ave NW Washington DC 20015 

Nov. 21, 2009 

Please reverse your decision to set a federal limite for perchlorate in drinking water. This chemical 

had deleterious effects on national health, even in very small amounts. Your job is to protect public 

health. Please do so and regulate perchlorate. 

Deborah Classman 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 939 of 1099

Response: See response to comment code 6120. 

Commenter Name: Joseph (illegible) 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2348 

EPA Comment ID: 25045 

EPA Comment Code: 6120 

 

Comment: Dear Department of Environmental Protection, 

As an uncle of 13 children and a father-to-be I find it at the minimum troubling, and at most a 

travesty of justice that your body has decided not to regulate perchlorate in drinking water. It has 

been brought to my attention that even low levels of this chemical can have adverse health effects. 

The lack of care and disregard for what is right, good, and just, I find personally appalling. I propose 

that you and your body seriously reexamine your policies and your morals. I thank you for your time 

and courtesy in hearing me voice my complaints. I trust that in the end you will make the right 

decision. 

Yours truly, Joseph [illegible] M.D. 

Response: See response to comment code 6120. 

Commenter Name: Wesley Thomas 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2349 

EPA Comment ID: 25046 

EPA Comment Code: 6120 

 

Comment: EPA Water Docket 

Perchlorate, a substance found in solid rocket fuels has no place in water. This substance needs to 

be kept out of the environment in order that it not stunt the growth of children like my daughter 

Victoria. 

Wesley Thomas 405 East Luray Avenue Unit A Alexandria, VA 22301-1603 (202) 412-2926 

Response: See response to comment code 6120. 

Commenter Name: Enn Ki Janz 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2350 

EPA Comment ID: 25047 

EPA Comment Code: 6120 

 

Comment: Dear EPA Water Docket 

Please regulate perchlorate. Harms children development 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 940 of 1099

Enn Ki Janz 5331 Holmes Run Pkwy Alexandria VA 22304 

Response: See response to comment code 6120. 

Commenter Name: Mary Cianningin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2351 

EPA Comment ID: 25048 

EPA Comment Code: 6120 

 

Comment: EPA Water 

Please regulate perchlorate its a harmful substance. 

Mary Cianningin 540 E. Luray Ave. Alexandria, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Mary Cianningin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2351 

EPA Comment ID: 25049 

EPA Comment Code: 6120 

 

Comment: EPA Water 

Please regulate perchlorate its a harmful substance. 

Mary Cianningin 540 E. Luray Ave. Alexandria, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2352 

EPA Comment ID: 25050 

EPA Comment Code: 6120 

 

Comment: EPA: 

PLEASE REGULATE PERCHLORATE - IT IS A HARMFUL SUBSTANCE. 

[illegible] 10 E. Rosemont Alex, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Selma Munden 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 941 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-2353 

EPA Comment ID: 25051 

EPA Comment Code: 6120 

 

Comment: EPA Water Docket 

Please regulate perchlorate its a harmful substance. 

Selma Munden 508E Luray Ave. Alexandria, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Christine Kulinski 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2354 

EPA Comment ID: 25052 

EPA Comment Code: 6120 

 

Comment: DEAR EPA REPRESENTATIVE - 

PLEASE ENSURE OUR CITIZENS ARE NOT EXPOSED TO PERCHLORATE IN OUR 

WATER. 

THANK YOU, CHRISTINE KULINSKI 

Response: See response to comment code 6120. 

Commenter Name: Leslie Durs 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2355 

EPA Comment ID: 25053 

EPA Comment Code: 6120 

 

Comment: Dear EPA representative, 

Please ensure our children are not exposed to perchlorate in our waters. 

Thank you, Leslie Durs 128 E Rosemont Ave Alexandria VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Jeannie Sharp 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2356 

EPA Comment ID: 25054 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 942 of 1099

Perchlorate is a dangerous chemical and I believe we should set a limit on it. 

Jeannie Sharp 906 N. Overlook Dr. Alexandria, VA 22305 

Response: See response to comment code 6120. 

Commenter Name: Avis Rana 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2357 

EPA Comment ID: 25055 

EPA Comment Code: 6120 

 

Comment: Portland, Oregon November 4, 2008 

Environmental Protection Avenue NW Washington DC 20460 

Re: Docket EPA-HQ-OW-2008-0692 Drinking Water Preliminary Regulatory Determination 

This letter is to request that your agency set a drinking water standard for perchlorate, consistent 

with the legislation endorsed by the Senate Environment and Public Works Committee, and that 

you monitor levels of the chemical in tap water. 

Perchlorate is a chemical in rocket fuel that has been linked to thyroid problems in pregnant women, 

newborns and young children. The maximum safe level now established in drinking water is 15 

times higher than what the EPA declared safe in 2002. Under this new standard, more than 16 

million Americans would be exposed to unsafe levels of perchlorate in their drinking water, placing 

more than 16 million Americans at risk. Perchlorate has been found in the drinking water in 35 

states in the U.S. 

I hope you will set a federal standard establishing safe levels for perchlorate in drinking water and 

will make provision for monitoring which will assure that Americans can be assured their drinking 

water is free from this dangerous chemical. 

Sincerely, Avis Rana 

Response: See response to comment code 6120. 

Commenter Name: Laura Milleker 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2358 

EPA Comment ID: 25056 

EPA Comment Code: 6120 

 

Comment: Laura Milleker 112 A Askewton Rd S.P., M.D. 21146 

Water Docket EPA Mailcode 2822T 1200 Pennsylvania Ave. Washington, D.C. 20460 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 943 of 1099

Re Docket ID No. EPA-HQ-OW-2008-0692 

I am writing to voice my strong opposition to not put regulations on perchlorate in drinking water. 

Perchlorate contamination is a nationwide problem. A national primary drinking water regulation is 

needed to protect public health. 

Sincerely, Laura Milleker 

Response: See response to comment code 6120. 

Commenter Name: Kathryn L. Jacobson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2359 

EPA Comment ID: 25057 

EPA Comment Code: 6120 

 

Comment: Kathryn L. Jacobson 3306 Holly Street Alexandria, VA 22305 

Water Docket Environmental Protection Agency Mailcode 2822T 1200 Pennsylvania Avenue 

Washington, D.C. 20460 

ATTN: Docket ID No. EPA-HQ-OW-2008-0692 

To Whom It May Concern: 

I am writing regarding percholate contamination, which is a nationwide problem and has health 

impacts at lower levels than previously thought. Please reverse your previous decision and provide a 

national primary drinking water regulation to prevent percholate contamination and protect the 

public health. 

Thank you for your attention. 

Sincerely, Kathryn Jacobson 

Response: See response to comment code 6120. 

Commenter Name: Leslie 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2360 

EPA Comment ID: 25058 

EPA Comment Code: 6120 

 

Comment: 11/24/08 

To EPA Water Docket, 

I am a Virginia voter. Perchlorate is a dangerous chemical found in 37 states. It gets into water and 

effects the health of children, so it should be regulated. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 944 of 1099

Sincerely, Leslie [illegible] 602 N. Pickett St Alexandria, Va 22304 

Response: See response to comment code 6120. 

Commenter Name: Lewis Tara 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2363 

EPA Comment ID: 25059 

EPA Comment Code: 6120 

 

Comment: EPA Water Docket, 

Please regulate perchlorate! I have two young girls and would love to know that our water is as safe 

as possible! 

Sincerely, Tara Lewis 522 E Luray Ave Alexandria, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2364 

EPA Comment ID: 25060 

EPA Comment Code: 6120 

 

Comment: Dear EPA 

Please regulate perchlorate. This is a harmful substance with known substitutes. 

[Illegible] 12 W. Rosemont Ave Alexandria, VA 22301 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0036 

EPA Comment ID: 28336 

EPA Comment Code: 6120 

 

Comment: I support EPA including Perchlorate on the National Primary Drinking Water List. I am 

especially concerned that it is not included to date as a pregnant woman. Small changes in maternal 

thyroid hormone levels during pregnancy have been associated with reduced IQs in children and 

high levels of perchlorate in the water could lead to mental retardation in children of mothers who 

consumed contaminated water. This is not just a health concern for fetuses and infants, but for 

anyone in our country suffering any kind of thyroid problems. Which considering how unhealthy 

Americans are, there are probably plenty of people who suffer from thyroid issues. Perchlorate 

allowed in the drinking water will only decrease the health of our population. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 945 of 1099

California has already taken steps to regulate this contaminant, EPA should too. EPA guideline of 1 

part per billion for its public drinking water standard should be enforceable, not just a 

recommendation. EPA should be protecting human health and the environment, not industry. I 

sincerely hope and pray that EPA will go back to its mission statement and ignore industry 

influences. Fight for us and the environment, regulate Perchlorate in the drinking water today! 

Response: See response to comment code 6120. 

Commenter Name: W. Cucinotta 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0038 

EPA Comment ID: 28339 

EPA Comment Code: 6120 

 

Comment: d. EPA should regulate all exposures from these types of chemicals as we know little 

about the harm they cause when exposed to or mixed with different medicines or the multiple other 

chemicals in our bodies or in individual water systems. Because there is not enough data about our 

exposures to these chemical "soups" to assure protection for the American people and until there is 

more data assuring our safety from mixing perchlorates with other drugs and chemicals, EPA should 

aim to control all exposure. 

Response: See response to comment code 6120. 

Commenter Name: Kathryn Taylor 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0041 

EPA Comment ID: 28340 

EPA Comment Code: 6120 

 

Comment: Please consider our lives and our health and set a reasonable limit to perchlorate in 

drinking water. Our lives and our future depend on you. Don't be swayed by those with money and 

power. You are in your position to protect others. 

Sincerely, Kathryn Taylor 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0043 

EPA Comment ID: 28341 

EPA Comment Code: 6120 

 

Comment: I live in NJ and already face a multitude of pollution issues, so I urge the U.S. 

Environmental Protection Agency to move forward with a drinking water standard of no higher 

than 1 part per billion for perchlorate. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 946 of 1099

Response: See response to comment code 6120. 

Commenter Name: Deborah Roney 

Commenter Organization: Clean Water Action 

EPA Document ID: EPA-HQ-OW-2009-0297-0045 

EPA Comment ID: 28342 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. Perchlorate contamination is a 

nationwide problem and has health impacts at lower levels than previously thought; 

To assist in keeping down health care costs to our country, protecting infants and children against 

this polutant is critical. A national primary drinking water regulation would provide a unique preemptive opportunity to protect public health. One that our government is responsible to do. 

Thank you for taking action to protect our health and our economy. 

Deborah Roney 

Response: See response to comment code 6120. 

Commenter Name: L. Obara 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0051 

EPA Comment ID: 28343 

EPA Comment Code: 6120 

 

Comment: PLEASE KEEP PERCHOLATE OUT OF OUR DRINKING WATER! WE RELY 

ON YOU TO SET HEALTHY STANDARDS FOR ALL OF US! Perchlorate, even in small 

amounts, can impair the thyroid gland, which controls growth, development and metabolism. 

Developing fetuses, infants and children with thyroid impairment may suffer mental retardation, loss 

of hearing and speech or deficits in motor skills. 

Response: See response to comment code 6120. 

Commenter Name: A.J. Melman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0058 

EPA Comment ID: 28344 

EPA Comment Code: 6120 

 

Comment: Please regulate Perechlorate in drinking water. It does not belong in our water and it is 

your mandate to protect citizens from contaminates in our public water supplies. 

Response: See response to comment code 6120. 

Commenter Name: C. Ernst 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 947 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0063 

EPA Comment ID: 28345 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. perchlorate contamination is a 

nationwide problem and has health impacts at lower levels than previously thought; protecting 

infants and children is critical. a national primary drinking water regulation would provide a 

meaningful opportunity to protect public health. Why limit perchlorate? 

Perchlorate is a harmful chemical that EPA claims has been found in 395 sites in 37 states, including 

153 public water systems serving over 20 million people. Some estimates are even higher. 

Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development and metabolism. Developing fetuses, infants and children with thyroid impairment 

may suffer mental retardation, loss of hearing and speech or deficits in motor skills 

Response: See response to comment code 6120. 

Commenter Name: Beth Appelbaum 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0064 

EPA Comment ID: 28346 

EPA Comment Code: 6120 

 

Comment: Please take perchlorate out of our drinkiing water! I already have thyroid issues and do 

not need any other problems nor want youing children to have issues. beth appelbaum 

Response: See response to comment code 6120. 

Commenter Name: Toula J. Halperin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0066 

EPA Comment ID: 28347 

EPA Comment Code: 6120 

 

Comment: I urge the EPA to limit Perchlorate to 1 part per billion in our drinking water. This is 

especially important for the health and well being of young children. Yours sincerely, Toula J. 

Halperin 18 Watchung Road Short Hills, NJ 07078 

Response: See response to comment code 6120. 

Commenter Name: Samuel Fuller 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0071 

EPA Comment ID: 28348 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 948 of 1099

Comment: Dear EPA 

Your job is to protect US citizens- and the environment. Given the article in today's Sunday NY 

Times your incompetence and inertia is inexcusable. Please wake up to the tragedy before you and 

ban rocket fuel from our drinking water. 

Fr Samuel Fuller 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0072 

EPA Comment ID: 28349 

EPA Comment Code: 6120 

 

Comment: Being a student of the medical field I can tell you that perchlorate must be limited and 

should NOT be in our drinking water in random amounts! Please take whatever actions necessary to 

limit this highly effective and in large amounts, toxic substance in our country's drinking water 

supply. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0074 

EPA Comment ID: 28351 

EPA Comment Code: 6120 

 

Comment: I believe we need to set a limit on the allocated amount of perchlorate in our country's 

drinking water. This chemical/ compound in known to be harmful to humans if ingested. We can 

not allow this problem to persist into the waters of our united states citizens any longer. 

Response: See response to comment code 6120. 

Commenter Name: J. Nadeau 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0086 

EPA Comment ID: 28352 

EPA Comment Code: 6120 

 

Comment: Keep perchlorate out of my drinking water! 

Response: See response to comment code 6120. 

Commenter Name: Robert J. O'Connell 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0092 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 949 of 1099

EPA Comment ID: 28354 

EPA Comment Code: 6120 

 

Comment: To Whom It May Concern: Please take action to STOP PERCHLORATE from 

entering our water systems. Recent studies seem to indicate that the threshhold levels at which 

serious harm to a fetus and onset of mental retardation, among other dangers, are lower than the 

originally predicted. Thank you for all you do to protect our health and our environment. Yours 

truly, Robert J.O'Connell 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0097 

EPA Comment ID: 28355 

EPA Comment Code: 6120 

 

Comment: No rocket fuel in our drinking water!! 

Response: See response to comment code 6120. 

Commenter Name: B. Beckel 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0112 

EPA Comment ID: 28356 

EPA Comment Code: 6120 

 

Comment: Please set a minuscule amount of Perchhlorate allowable in our drinking water. We 

believe reports that indicate many health problems and especially effects on the unborn from 

exposure to small amounts of Perchlorate. Now is the time for us to take charge of how our societal 

penchant for war and the profits of war affect our environment. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0113 

EPA Comment ID: 28357 

EPA Comment Code: 6120 

 

Comment: A national primary drinking water regulation would send a message to the rest of the 

world that the United States practices what it preaches, but more importantly woul dprotect this 

country's citizens. Therefore I urge the U.S. Environmental Protection Agency to move forward 

with a drinking water standard of no higher than 1 part per billion for perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: L. Touzeau 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 950 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0121 

EPA Comment ID: 28359 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. perchlorate contamination is a 

nationwide problem and has health impacts at lower levels than previously thought; protecting 

infants and children is critical.a national primary drinking water regulation would provide a 

meaningful opportunity to protect public health. 

Why limit perchlorate? Perchlorate is a harmful chemical that EPA claims has been found in 395 

sites in 37 states, including 153 public water systems serving over 20 million people. Some estimates 

are even higher.Perchlorate, even in small amounts, can impair the thyroid gland, which controls 

growth, development and metabolism.Developing fetuses, infants and children with thyroid 

impairment may suffer mental retardation, loss of hearing and speech or deficits in motor skills. 

Response: See response to comment code 6120. 

Commenter Name: L. Kier 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0123 

EPA Comment ID: 28360 

EPA Comment Code: 6120 

 

Comment: Please keep percholate out of our drinking water. It is afffecting my thyrois and my 

daughter's speech. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0127 

EPA Comment ID: 28362 

EPA Comment Code: 6120 

 

Comment: Please,I urge the U.S. Environmental Protection Agency to move forward with a 

drinking water standard of no higher than 1 part per billion for perchlorate. Do it for your children 

Response: See response to comment code 6120. 

Commenter Name: B. Harris 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0135 

EPA Comment ID: 28364 

EPA Comment Code: 6120 

 

Comment: Please keep perchlorate out of our drinking water. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 951 of 1099

Response: See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #10 - Group Unidentified 

EPA Document ID: EPA-HQ-OW-2009-0297-0039 

EPA Comment ID: 28365 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. 

perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; 

protecting infants and children is critical.a national primary drinking water regulation would provide 

a meaningful opportunity to protect public health. 

Response: See response to comment code 6120. 

Commenter Name: J. Capozzelli 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0088 

EPA Comment ID: 28366 

EPA Comment Code: 6120 

 

Comment: The U.S. Environmental Protection Agency (EPA) has still not decided whether to set a 

drinking water standard, a limit for perchlorate, an ingredient in rocket fuel that is contaminating 

water nationwide. Perchlorate is a harmful chemical that the EPA claims has been found in 395 sites 

in 37 states, including 153 public water systems serving over 20 million people. Some estimates are 

even higher. Perchlorate, even in small amounts, can impair the thyroid gland, which controls 

growth, development and metabolism. Developing fetuses, infants and children with thyroid 

impairment may suffer mental retardation, loss of hearing and speech or deficits in motor skills. I 

urge the U.S. Environmental Protection Agency to move forward with a drinking water standard of 

no higher than one part per billion for perchlorate because berchlorate contamination is a 

nationwide problem and has health impacts at lower levels than previously thought. A national 

primary drinking water regulation would provide a meaningful opportunity to protect public 

health.Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Noreen P. Cullen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0136 

EPA Comment ID: 28367 

EPA Comment Code: 6120 

 

Comment: Dear Sir/Madam; 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 952 of 1099

Perchlorate has been shown to be dangerous to human health and should not be ingested by 

anyone, especially by children. We need to do everything we can to remediate the waters that 

currently contain perchlorate and do even more to prevent further intrusion of perchlorate into the 

waters in our country. 

Noreen P. Cullen 30 Delmar Rd Glastonbury, CT 06033 noreen@faeryspirit.com 

Response: See response to comment code 6120. 

Commenter Name: D. Browder 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0140 

EPA Comment ID: 28368 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. - perchlorate contamination is a 

nationwide problem and has health impacts at lower levels than previously thought; protecting 

infants and children is critical. - a national primary drinking water regulation would provide a 

meaningful opportunity to protect public health. If perchlorate is affecting the thyroid as 

substantially as indicated, it could also be contributing to the obesity of our nation. It could be 

slowing down the metabolism for those who would otherwise burn calories much more easily but 

because of a chemical issue going on in their body, it is slowed down significantly. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0146 

EPA Comment ID: 28369 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of NO parts per billion for perchlorate. 

- perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; protecting infants and children is critical. - a national primary drinking water 

regulation would provide a meaningful opportunity to protect public health. 

I mean, think about it. This affects YOUR water too! 

Response: See response to comment code 6120. 

Commenter Name: Joe Parrish 

Commenter Organization: US Environmental Watch 

EPA Document ID: EPA-HQ-OW-2009-0297-0148 

EPA Comment ID: 28370 

EPA Comment Code: 6120 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 953 of 1099

 

Comment: I very urgently ask the U.S. Environmental Protection Agency to move forward with a 

drinking water standard of no higher than 1 part per billion for perchlorate. 

Perchlorate contamination is a nationwide problem and has health impacts at far lower levels than 

previously thought; without this protection, infants and children will be damaged. 

Perchlorate in concentrations above 1 PPB will impair the thyroid gland, which controls growth, 

development and metabolism. Developing fetuses, infants and children with thyroid impairment will 

suffer mental retardation, loss of hearing and speech and deficits in motor skills. 

A national primary drinking water regulation at 1 PPB for perchlorate is absolutely essential to 

protect public health. 

Do not delay adopting this essential limit for perchlorate. 

Sincerely, Dr. Joe Parrish US Environmental Watch 300 E. 56th Street Suite 2B New York, NY 

10022 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0152 

EPA Comment ID: 28371 

EPA Comment Code: 6120 

 

Comment: As one who individually and whose children have been severely negatively impacted by 

Agent Orange (Dioxin), I can not imagine how anyone could be persuaded to allow Perchlorate 

reach our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Susanne Emerick 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0155 

EPA Comment ID: 28372 

EPA Comment Code: 6120 

 

Comment: It is time to pass safer water regs. Keep perchlorate out of our drinking water. 

Susanne Emerick 

Response: See response to comment code 6120. 

Commenter Name: Albert A. Bartlett 

Commenter Organization: University of Colorado at Boulder 

EPA Document ID: EPA-HQ-OW-2009-0297-0161 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 954 of 1099

EPA Comment ID: 28374 

EPA Comment Code: 6120 

 

Comment: Dear Friends, 

Please do all you can to keep perchlorate out of the drinking water systems. 

With thanks and best wishes, I am, 

Sincerely yours, Albert A. Bartlett Professor Emeritus of Physics, University of Colorado at Boulder. 

Response: See response to comment code 6120. 

Commenter Name: Beth Robelia 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0162 

EPA Comment ID: 28375 

EPA Comment Code: 6120 

 

Comment: To whom it may concern: 

Please set a standard to limit perchlorate in water. Data indicates it is hazardous to human health 

and should not be consumed by children or pregnant women. Limiting consumption by setting 

limits seems the most prudent course of action. 

Regards, Beth Robelia 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0168 

EPA Comment ID: 28377 

EPA Comment Code: 6120 

 

Comment: No more than one part per billion of perchlorate in our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0171 

EPA Comment ID: 28378 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 955 of 1099

Response: See response to comment code 6120. 

Commenter Name: Patrick Iannone 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0172 

EPA Comment ID: 28379 

EPA Comment Code: 6120 

 

Comment: Dear Sirs/Madams, 

As an industrial research scientist, I urge the U.S. Environmental Protection Agency to adopt a 

drinking water standard of no higher than 1 part per billion for perchlorate. 

As we've seen over the past decade or more, the lack of strict government oversight in critical areas 

(such as the public health, banking, etc) leads to abuses by large corporations. Please continue your 

role in protecting infants and children from contaminated drinking water. 

Regards, Patrick Iannone, Ph.D 146 Davis Lane Red Bank NJ, 07701 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0173 

EPA Comment ID: 28380 

EPA Comment Code: 6120 

 

Comment: I urge the Environmental Protection Agency to set the drinking water standard for 

perchlorate to no more than 1 part /billion. 

Although there are a number of health concerns with this chemical, I am especially concerned about 

the mischief it causes in thyroid function. As a federal government, we can take on the expenses of 

life-long medical care or we can fulfill our preemptive responsibilities to protect American citizens 

from a lifetime of disability. Please be strong and say "no" to relaxed standards for Perc. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0174 

EPA Comment ID: 28381 

EPA Comment Code: 6120 

 

Comment: I am a concerned citizen and would like to facilitate change in my world. I don't like 

being killed with pollution by people and companies that are taking advantage of all of us. I have 

zero tolerance for pollution, greed and ignorance! Please get help get our world livable again. Stop 

perchlorate in water. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 956 of 1099

Response: See response to comment code 6120. 

Commenter Name: Linc Cole 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0175 

EPA Comment ID: 28382 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. 

Linc Cole 120 Cutlass Ln Cudjoe Key, FL 33042 

Response: See response to comment code 6120. 

Commenter Name: Bob Vaughan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0178 

EPA Comment ID: 28383 

EPA Comment Code: 6120 

 

Comment: please set a national limit on the amount of the harmful chemical perchlorate allowed in 

our nation's drinking water. 

thank you, Bob Vaughan Tampa,Florida 

Response: See response to comment code 6120. 

Commenter Name: R. Van Aken 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0180 

EPA Comment ID: 28385 

EPA Comment Code: 6120 

 

Comment: The continual revelations regarding chemicals in our drinking water suggest we err on 

the side of caution regarding permissible limits. As we know the effects this chemical has on human 

beings I urge you to set the limit as low as feasible to prevent serious the serious health problems 

possible from inadvertent consumption of this chemical. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0187 

EPA Comment ID: 28386 

EPA Comment Code: 6120 

 

Comment: Please set a high standard for limiting this chemical in our drinking water. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 957 of 1099

Response: See response to comment code 6120. 

Commenter Name: Maureen Lattimore 

Commenter Organization: Robert Bair Services 

EPA Document ID: EPA-HQ-OW-2009-0297-0195 

EPA Comment ID: 28388 

EPA Comment Code: 6120 

 

Comment: We need stronger legislation on keeping our water clean. There is only so much water 

and every day there is more data about that fact showing up and letting us know that the situation is 

getting worse. Please take strong action to keep our drinking water free of Perchlorate and other 

hazardous chemicals. 

Response: See response to comment code 6120. 

Commenter Name: Peggi Sturmfels 

Commenter Organization: New Jersey Environmental Federation (NJEF) 

EPA Document ID: EPA-HQ-OW-2009-0297-0204 

EPA Comment ID: 28389 

EPA Comment Code: 6120 

 

Comment: I am a program organizer for NJ Environmental Federation as well as a mom and 

grandmother. 

My deep concern about perchlorate in our waterways is growing. Particularly in regards to NJ which 

is now becoming a superfort by combining FT Dix, Mcquire Air Force Base and Lakehurst Navel 

Air Station. As a results, military air traffic has increased from 8000 to 80,000 over Centerl Jersey, 

which is home to the headwaters of the Metedeconk and Toms River and the Kirkwood Cohansey 

aquifer that supply most of the drinking water for central and South Jersey. Added to that, this area 

is less than 50 miles in any direction from a major commercial airport. 

Setting standards for perchlorate at one part per billion is the only reasonable action that can be 

taken protect the children and residents of this area. Sadly you may be too late. 

Response: See response to comment code 6120. 

Commenter Name: K. Cunningham 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0218 

EPA Comment ID: 28391 

EPA Comment Code: 6120 

 

Comment: Gentlemen; 

I have read for a number of years about the infiltration of perchlorate mostly from some federal (or 

Federal contractor) facilities through ground water or other discharges into surface waters. 

Perchlorate contamination is found (for example) in the Colorado River system and in irrigation and 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 958 of 1099

domestic water supplies drawing on it. Many of the California vegetables which millions of 

Americans enjoy have some perchlorate contamination. People with some knowledge of chemistry 

often assume that perchlorate is, like sulfate, fairly inert and innocuous at low concentrations. 

However, I understand that there is evidence that perchlorate has effects on thyroid health, even at 

sub-ppm concentrations, and it is known that its bromine analog, bromate, is to be avoided due to 

its toxic effects at low concentrations (one of the reasons that ozonation is not a viable drinking 

water treatment when bromide ion is present). For these reasons, and because the sources of 

perchlorate contamination are fairly limited, I would ask that EPA begin to regulate this chemical 

more stringently in discharges and in drinking water supplies, perhaps down to the 1 ppb level in the 

latter. Thank you for your consideration of this opinion. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0223 

EPA Comment ID: 28392 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. 

Perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; protecting infants and children is critical. 

a national primary drinking water regulation would provide a meaningful opportunity to protect 

public health. 

5 years ago, I developed hypothyroidism. There is no family history of this. I know many others. I 

can't help but wonder if perchlorate in the water used to grow vegetables in the western U.S. states 

is partly responsible. At age 51, the health concerns for me are nothing compared to those of 

children exposed to this. Please take action to help protect our health. Thank You. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0234 

EPA Comment ID: 28393 

EPA Comment Code: 6120 

 

Comment: Common sense dictates that we keep our water supplies clean of pollutants. Why is that 

so hard to commit to? Please keep perchlorate and other contaminants out of the water. 

I urge the U.S. Environmental Protection Agency to move forward with a drinking water standard 

of no higher than 1 part per billion for perchlorate. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 959 of 1099

Commenter Name: Nancy Kuecke 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0238 

EPA Comment ID: 28417 

EPA Comment Code: 6120 

 

Comment: I strongly recommend setting a limit NOW on the amount of perchlorate allowed in our 

drinking water! 

Thank you for your time and effort. 

Nancy Kuecke 

Response: See response to comment code 6120. 

Commenter Name: Merryl Gladstone 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0245 

EPA Comment ID: 28419 

EPA Comment Code: 6120 

 

Comment: As a mother and a concerned citizen, I am writing in support of regulations restricting 

perchlorate in America's drinking water. It is dangerous and not what we as American citizen 

deserve in our drinking water. Listen to the scientific evidence and do write by people NOT 

industry. You are our voice. 

Response: See response to comment code 6120. 

Commenter Name: Patricia McPeak-La Rocca 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0255 

EPA Comment ID: 28420 

EPA Comment Code: 6120 

 

Comment: I am a Certified Nurse- Midwife, and I write on behalf on pregnant women, their 

unborn fetuses, babies, children, families and individual citizens,who do NOTwant the inclusion of 

any amount of perchlorate in our drinking water. We rely on the EPA to protect our water sources 

and prevent public health problems. This is a substance known to be harmful in the scientific 

literature. We must be willing to protect our most vulnerable citizens who are not yet of age: babies 

and children. This is also a case of The Precuationary Principal; safety must be proven and not 

assumed. 

I urge the U.S. Environmental Protection Agency to move forward and limit the amount of 

perchlorate in water to no greater than 1 part per billion. 

Sincerely, Patricia McPeak- La Rocca, CNM Amherst, MA 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 960 of 1099

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0256 

EPA Comment ID: 28421 

EPA Comment Code: 6120 

 

Comment: I urge you to set regulations banning perchlorate of concentrations higher than 1 part 

per billion in drinking water. Perchlorate (even in small amounts) is linked to thyroid damage, which, 

in fetuses and children, can lead to intelligence disability (mental retardation), loss of hearing and 

speech, or motor impairment. It is unconscionable to allow the levels or perchlorate in drinking 

water to go unpunished and untreated. 

Response: See response to comment code 6120. 

Commenter Name: Walter McClure 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0265 

EPA Comment ID: 28422 

EPA Comment Code: 6120 

 

Comment: On August 19, the U.S. Environmental Protection Agency (EPA) requested public 

comments related to setting a limit for perchlorate in drinking water. Last year EPA appeared poised 

to announce that it would not set a limit but is now reviewing scientific and other information to 

make a decision about moving forward with a regulation now. 

Why limit perchlorate. It is a harmful chemical that EPA claims has been found in 395 sites in 37 

states, including 153 public water systems serving over 20 million people. Some estimates are even 

higher. 

Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development and metabolism. 

Developing fetuses, infants and children with thyroid impairment may suffer mental retardation, loss 

of hearing and speech or deficits in motor skills. 

I urge the U.S. Environmental Protection Agency to move forward with a drinking water standard 

of no higher than 1 part per billion for perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: Nancy T. Miller 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0266 

EPA Comment ID: 28423 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 961 of 1099

Comment: I urge the EPA to set a standard on perchlorate of one part per billion to ensure safe 

drinking water for everyone. -- Nancy T. Miller, Winona MN 

Response: See response to comment code 6120. 

Commenter Name: Thomas Clark 

Commenter Organization: Clark Chiropractic Health Center, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0267 

EPA Comment ID: 28424 

EPA Comment Code: 6120 

 

Comment: We must keep this and so many other chemicals out of our drinking water. We must 

move ahead towards more pure water, not "tolerable" levels. 

Thomas Clark, D.C. St. Petersburg, FL 

Response: See response to comment code 6120. 

Commenter Name: Kathryn C. Westman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0268 

EPA Comment ID: 28425 

EPA Comment Code: 6120 

 

Comment: As a concerned citizen and registered nurse, I feel it is important for the US EPA to set 

a limit on Perchlorate in public drinking water, limiiting it to a standard of no higher than 1 

part/billion. 

We must protect the population - especailly children and infants- from the impairment on the 

thyroid gland that higher limits might cause. Please take this step to protect our public health. 

Sincerely, Kathryn C. Westman 104 S. Harleston Dr. Pittsburgh, PA 15237 

Response: See response to comment code 6120. 

Commenter Name: Susan van Asch van Wyck 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0275 

EPA Comment ID: 28427 

EPA Comment Code: 6120 

 

Comment: We cannot understand why you would want to allow ANY perchlorate in our drinking 

water!! It is no wonder so many millions of Americans die of cancer. We are all at risk every day 

because of lax governmental control, as we had during the Bush years. Please do not extend these 

dangers during the Obama administration. Thank you. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 962 of 1099

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0281 

EPA Comment ID: 28428 

EPA Comment Code: 6120 

 

Comment: please keep perchlorate out of our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0282 

EPA Comment ID: 28429 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. 

Health impacts of perchlorate are well documented and present serious problems, especially in 

children and infants. 

Another reason why I RO filter all my water. But not everyone does or can afford to do so. 

Response: See response to comment code 6120. 

Commenter Name: Karen Parelhoff 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0291 

EPA Comment ID: 28431 

EPA Comment Code: 6120 

 

Comment: We need perchlorate-free drinking water. Please regulate this harmful chemical to no 

more than one parts to a billion for our drinking water. We look to you to take care of us and 

protect our health from harmful chemicals in our soil, water, and air. 

Karen Parelhoff 

Response: See response to comment code 6120. 

Commenter Name: Elaine Kampmann 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0295 

EPA Comment ID: 28432 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 963 of 1099

Comment: I can't really imagine why there is much to debate here. I don't know if the agency has 

gotten stuck in some bureacreatic muddle, but our drinking water is becoming more and more 

contaminated and is already non-potable in areas of my city because of tri-chlor, per-chlor, etc. 

Keep it out of the water!!!! 

Thank you, Elaine Kampmann 2531 Wilkinson Rd. Sarasota FL 34231 

Response: See response to comment code 6120. 

Commenter Name: Pamela Hosler 

Commenter Organization: Hawthorn Children's Psychiatric Hospital, Missouri Department of 

Mental Health 

EPA Document ID: EPA-HQ-OW-2009-0297-0307 

EPA Comment ID: 28435 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. EPA to set a national limit on perchorlate in drinking water. It has been 

found in the public water systems that serve 20 million people. Small amounts affect the thyroid 

gland, which, in turn, can cause health problems. 

A national standard allowing no more than 1 ppb perchorlate in drinking water would prevent many 

many health problems. 

Response: See response to comment code 6120. 

Commenter Name: Mark Knight 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0309 

EPA Comment ID: 28437 

EPA Comment Code: 6120 

 

Comment: I urge EPA to move forward with an appropriate drinking water standard for 

perchlorate. The reason is simple: Perchlorate contamination is a nationwide problem and has health 

impacts at lower levels than previously thought; protecting infants and children is critical. 

Mark Knight Arlington, VA 

Response: See response to comment code 6120. 

Commenter Name: Linda Jeub 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0316 

EPA Comment ID: 28438 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 964 of 1099

Comment: The U.S. Environmental Protection Agency must move forward to protect our drinking 

water with a standard of no higher than 1 part per billion for perchlorate. How rocket fuel gets into 

our drinking water is beyond me. 

From what I have heard, perchlorate contamination is showing up nationally, and has health impacts 

at lower levels than previously thought putting infants and children at risk. 

We are at a point in our environmental history that requires paying attention to the basics and 

drinking water is about as basic as it gets. A national primary drinking water regulation would be a 

meaningful step in protecting public health. 

Thank you, Linda Jeub 

Response: See response to comment code 6120. 

Commenter Name: Robert H. Michels 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0317 

EPA Comment ID: 28439 

EPA Comment Code: 6120 

 

Comment: Please do not allow perchlorate into the drinking water in this country!! 

Sincerely, Robert H. Michels 917-991-1367 rmichels57@yahoo.com 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0318 

EPA Comment ID: 28440 

EPA Comment Code: 6120 

 

Comment: Please ensure that perchlorate is kept put of our drinking water. This is critical. 

Response: See response to comment code 6120. 

Commenter Name: Greg Black 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0320 

EPA Comment ID: 28442 

EPA Comment Code: 6120 

 

Comment: About proposed regulations on Perchlorate in our water: 

I am adamantly oppsed to allowing this chemical to continue to be dumped into my water. The U.S. 

Environmental Protection Agency should enforce a drinking water standard of no higher than 1 part 

per billion for perchlorate (I would prefer a more strick standard.). 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 965 of 1099

Also, whant are we going to see some movement on Mercury Standards for coal powered plants? 

We voted for change, and I want to see it now in EPS enforecement. 

Most Sincerely, 

Greg Black 

Response: The issue of mercury standards for coal powered plants is outside the scope of this 

action. For your comment on perchlorate, see response to comment code 6120. 

Commenter Name: Pauline DiBella 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0321 

EPA Comment ID: 28443 

EPA Comment Code: 6120 

 

Comment: Nobody wants rocket fuel in their drinking water. 

Why limit perchlorate???? 

- Perchlorate is a harmful chemical that EPA claims has been found in 395 sites in 37 states, 

including 153 public water systems serving over 20 million people. Some estimates are even higher. - 

Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development and metabolism. - Developing fetuses, infants and children with thyroid impairment 

may suffer mental retardation, loss of hearing and speech or deficits in motor skills. 

Sample Letter 

I urge the U.S. Environmental Protection Agency to move forward with a drinking water standard 

of no higher than 1 part per billion for perchlorate. 

- perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; protecting infants and children is critical. - a national primary drinking water 

regulation would provide a meaningful opportunity to protect public health. Please act now to 

regulate perchlorate and protect our water supply. 

thank you. 

Pauline DiBella Devon, Pennsylvania 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0330 

EPA Comment ID: 28444 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 966 of 1099

EPA Comment Code: 6120 

 

Comment: Please keep perchlorate out of drinking water. The safety of the public is vital! 

Response: See response to comment code 6120. 

Commenter Name: A. Crane 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0331 

EPA Comment ID: 28445 

EPA Comment Code: 6120 

 

Comment: Let's keep our water safe! Please! I recently attended an Herbalists Festival and the 

attendance was double what the organizers had expected and many of the attendees were there to 

learn about caring for the lymphatic system. If it is proven and known that the perchlorate found in 

rocket fuel is bad for the thyroid and causes birth defects and has been found in 37 states then I 

hope and pray you get busy on regulating the presence of this chemical in our water ways, all of 

them - rivers, lakes, streams, wetlands and our city water systems. Who wants the rain to bring us 

cancer? I don't. Please work to stop the polluting, dumping and excess production of this hazardous 

substance. Thank you. Sincerely, A. Crane 

Response: See response to comment code 6120. 

Commenter Name: M. Dougherty 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0334 

EPA Comment ID: 28446 

EPA Comment Code: 6120 

 

Comment: I am very concerned about Perchlorate contaminating our drinking water. Please set 

standards to eliminiated this threat to our health and the health of future generations. 

Response: See response to comment code 6120. 

Commenter Name: Damon J. Brinson 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0340 

EPA Comment ID: 28448 

EPA Comment Code: 6120 

 

Comment: I am writing to urge the U.S. Environmental Protection Agency to move forward with a 

drinking water standard of no higher than 1 part per billion for perchlorate. 

Perchlorate contamination of drinking water is a serious problem across our nation. The chemical 

impacts people's health at lower levels than previously thought. It is critical to protect infants and 

children from this toxic chemical. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 967 of 1099

I firmly believe that a federal drinking water regulation, with a standard of <= 1 PPB of perchlorate, 

would protect public health. Please support this standard. 

Thank you, Damon J. Brinson 4860 Dona Lane Golden Valley, MN 55422 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0346 

EPA Comment ID: 28450 

EPA Comment Code: 6120 

 

Comment: Nobody wants rocket fuel in their drinking water. 

Response: See response to comment code 6120. 

Commenter Name: R. Oliver 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0347 

EPA Comment ID: 28451 

EPA Comment Code: 6120 

 

Comment: Nobody wants rocket fuel in their drinking water. 

Perchlorate is a harmful chemical that EPA claims has been found in 395 sites in 37 states, including 

153 public water systems serving over 20 million people. Some estimates are even higher. 

Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development and metabolism. Developing fetuses, infants and children with thyroid impairment 

may suffer mental retardation, loss of hearing and speech or deficits in motor skills. 

I urge the U.S. Environmental Protection Agency to move forward with a drinking water standard 

of no higher than 1 part per billion for perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: R. Oliver 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0356 

EPA Comment ID: 28453 

EPA Comment Code: 6120 

 

Comment: Nobody wants rocket fuel in their drinking water. 

Perchlorate is a harmful chemical that EPA claims has been found in 395 sites in 37 states, including 

153 public water systems serving over 20 million people. Some estimates are even higher. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 968 of 1099

Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development and metabolism. Developing fetuses, infants and children with thyroid impairment 

may suffer mental retardation, loss of hearing and speech or deficits in motor skills. 

I urge the U.S. Environmental Protection Agency to move forward with a drinking water standard 

of no higher than 1 part per billion for perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: G. Spring 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0361 

EPA Comment ID: 28455 

EPA Comment Code: 6120 

 

Comment: Please. No perchlorate in our water. Water is life. 

Response: See response to comment code 6120. 

Commenter Name: K. Stote 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0366 

EPA Comment ID: 28457 

EPA Comment Code: 6120 

 

Comment: Please don't allow perchlorate to be present in our drinking water without any limits, we 

need to set a maximum allowance amount. Do it for our future generations, cause once it's done, 

there's not a hell more we do to change it. 

Thank you. 

Response: See response to comment code 6120. 

Commenter Name: W. Brunkhorst 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0375 

EPA Comment ID: 28460 

EPA Comment Code: 6120 

 

Comment: The EPA has yet to set standards for perchorate,a component of aircraft fuel. It is 

critical to take action now,before perchlorate is detected in drinking water. Prevention is much 

cheaper than spending millions correcting a problem that is bound to occur. 

Response: See response to comment code 6120. 

Commenter Name: Susan Marie Frontczak 

Commenter Organization: Storysmith 

EPA Document ID: EPA-HQ-OW-2009-0297-0377 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 969 of 1099

EPA Comment ID: 28461 

EPA Comment Code: 6120 

 

Comment: Thyroid impairment, mental retardation, loss of hearing and speech, and motor skill 

deficits are all problems that can result from perchlorate contamination of drinking water. While the 

health care reform debate rages, let's make some common sense choices so that fewer people need 

health care or disability income. I urge the U.S. Environmental Protection Agency to move forward 

with a drinking water standard of no higher than 1 part per billion for perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: Janice Church 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0378 

EPA Comment ID: 28462 

EPA Comment Code: 6120 

 

Comment: Please make a scientific, not a political, decision regarding the allowable levels of 

percholate in our drinking water. 

Your decision will impact your children, my children, and our grandchildren. Please make your 

decision based on the best scientific evidence available. Please leave politics out of your equation as 

best you can. 

Thank you. Janice Church New Tennessee resident 

Response: See response to comment code 6120. 

Commenter Name: Michael Rice 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0386 

EPA Comment ID: 28463 

EPA Comment Code: 6120 

 

Comment: * Perchlorate is a harmful chemical that EPA claims has been found in 395 sites in 37 

states, including 153 public water systems serving over 20 million people. Some estimates are even 

higher. * Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development and metabolism. * Developing fetuses, infants and children with thyroid impairment 

may suffer mental retardation, loss of hearing and speech or deficits in motor skills. 

I urge the U.S. Environmental Protection Agency to move forward with a drinking water standard 

of no higher than 1 part per billion for perchlorate. 

* perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; protecting infants and children is critical. * a national primary drinking water 

regulation would provide a meaningful opportunity to protect public health. 

Thank you for hearing my concerns Sincerely, Michael Rice 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 970 of 1099

Response: See response to comment code 6120. 

Commenter Name: Jeff Franklin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0388 

EPA Comment ID: 28464 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

Please make our water safe from Perchlorate. NO amount is truly safe. Please think about your 

children and grandchildren drinking the water you approve. 

Be well, Jeff Franklin 720-570-2923 

Response: See response to comment code 6120. 

Commenter Name: L. Thorp 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0391 

EPA Comment ID: 28465 

EPA Comment Code: 6120 

 

Comment: PLEASE KEEP ROCKET FUEL OUT OF OUR DRINKING WATER,I DON'T 

WANT TO IMBIBE A GLASS OF IT AND "TAKE OFF" THANK YOU FOR YOUR 

ATTENTION TO THIS MATTER 

Response: See response to comment code 6120. 

Commenter Name: R. Downing 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0396 

EPA Comment ID: 28466 

EPA Comment Code: 6120 

 

Comment: The EPA should set a drinking water standard of no higher than 1 part per billion for 

perchlortae. This chemical does pose health risks and must be kept to a minimum. 

Response: See response to comment code 6120. 

Commenter Name: Sharon Biondi 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0401 

EPA Comment ID: 28467 

EPA Comment Code: 6120 

 

Comment: Dear Sirs, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 971 of 1099

Please limit the chemical perchclorate in our water supplies to a safe level. The cumulative effect on 

our young and future generations is dangerous at the present level. 

Thank you, Sharon Biondi 

Response: See response to comment code 6120. 

Commenter Name: Vorcelia Oliphant 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0410 

EPA Comment ID: 28470 

EPA Comment Code: 6120 

 

Comment: Please do not permit these substances in our drinking water. 

Thank you Vorcelia Oliphant 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0420 

EPA Comment ID: 28472 

EPA Comment Code: 6120 

 

Comment: Please keep our water safe by eliminating use of perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0435 

EPA Comment ID: 28473 

EPA Comment Code: 6120 

 

Comment: Please no Perchlorate in our water supply. None. 

Response: See response to comment code 6120. 

Commenter Name: Andria Ventura 

Commenter Organization: Clean Water Action et al. 

EPA Document ID: EPA-HQ-OW-2009-0297-0528 

EPA Comment ID: 28511 

EPA Comment Code: 6120 

 

Comment: From: Lenny Siegel To: Eric Burneson/DC/USEPA/US@EPA Cc: Andria Ventura 

Date: 09/18/2009 01:29 AM Subject: Re: Docket ID No. EPA-HQ-OW-2009-0297 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 972 of 1099

Eric, 

Please find attached a letter from community activists across the country calling upon EPA to 

regulate perchlorate and set a standard protective of ALL Americans. 

Lenny Siegel 

-- 

Lenny Siegel Executive Director, Center for Public Environmental Oversight a project of the Pacific 

Studies Center 278-A Hope St., Mountain View, CA 94041 Voice: 650/961-8918 or 650/969-1545 

Fax: 650/961-8918 

http://www.cpeo.org 

Attachment 

 September 4, 2009 

Mr. Eric Burneson Office of Ground Water and Drinking Water Standards and Risks Management 

Division Environmental Protection Agency 1200 Pennsylvania Avenue, NW, Mailcode 2822T 

Washington, D.C. 20460 

Re: Docket ID No. EPA-HQ-OW-2009-0297 

Dear Mr. Burneson, 

On behalf of our various organizations and our tens of thousands of members throughout the 

United States, we are writing to express our belief that the potential health impacts from exposure to 

perchlorate through drinking water are significant and that they warrant prompt regulation to 

protect public health and safety. Setting a drinking water standard will provide the U.S. 

Environmental Protection Agency (EPA) with a "meaningful opportunity for health risk reduction 

for persons served by public water systems." Consequently, EPA should move as quickly as possible 

to establish a more protective reference dose for perchlorate and then to promulgate a maximum 

contaminant level (MCL) for perchlorate that is no higher than one part per billion (ppb). We base 

this view on the scope of the contamination in drinking water supplies, exposure of the American 

population through other pathways, including food, and the most recent scientific studies that 

demonstrate serious health threats, even at low levels, to a larger portion of the population than 

previously recognized. These studies are based upon a much larger exposure data set than the 

studies upon which the current reference dose, and thus the entire regulatory regime, is based. 

Response: Regarding "establishing a more protective reference dose for perchlorate," see response 

to comment code 2110. Regarding EPA's decision to regulate perchlorate, see response to comment 

code 6120. 

Commenter Name: Andria Ventura 

Commenter Organization: Clean Water Action et al. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 973 of 1099

EPA Document ID: EPA-HQ-OW-2009-0297-0528 

EPA Comment ID: 28517 

EPA Comment Code: 6120 

 

Comment: A perchlorate drinking water standard of no higher than 1 ppb would protect a large 

share of the American population currently at risk. Given the scope of the perchlorate 

contamination nationally, the multiple exposure pathways and other environmental contaminants 

impacting thyroid function and development, and the data demonstrating a serious health threat to a 

significant part of the country's population, EPA is obligated to establish such a drinking water 

standard. We applaud the agency's consideration of how to move forward to regulate this 

contaminant and urge you to take steps to establish a protective MCL as soon as possible. 

 Sincerely, 

Andria Ventura Program Manager Clean Water Action San Francisco, CA 

Lenny Siegel Executive Director Center for Public Environmental Oversight Mountain View, CA 

Jeanne Rizzo, R.N. President Breast Cancer Fund San Francisco, CA 

 Debra Hall Founder Hopewell Junction Citizens for Clean Water Hopewell Junction, NY 

Peter Strauss President PM Strauss & Associates San Francisco, CA 

Pamela King Palitz Environmental Health Advocate and Staff Attorney Environment California San 

Francisco, CA 

Ansje Miller Policy Director Center for Environmental Health Oakland, CA 

Jerry Bowling III Behr VOC Area Leaders Dayton, Ohio 

Brian Moench, MD President Utah Physicians for a Healthy Environment 

David W. Campbell Secretary-Treasurer USW Local 675 Carson, CA 

Steven B. Pollack, Attorney Executive Director Blue Eco Legal Council Northbrook, IL 

Stephen M. Brittle Don't Waste Arizona Phoenix, AZ 

Dvija Michael Bertish Rosemere Neighborhood Association Vancouver, WA 

Luis Olmedo Velez Executive Director Comite Civico del Valle, Inc. Brawley, CA 

Kent Slowinski Environmental Health Group Washington, D.C. 

Laura Olah, Executive Director Citizens for Safe Water Around Badger Merrimac, WI 

Miriam Torres Environmental Justice Coalition for Water Santa Monica, CA 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 974 of 1099

Chris Nidel, M.S., J.D. Nidel Law, PLLC 

Jane Horton Mountain View, CA 

Dave Ness, Jr Bayport, MN 

John Yelenick SSAB - Rocky Mountain Arsenal Denver, CO 

Stephanie Smolen Former resident San Gabriel Valley, CA 

Barry Kissin, Esq. Member Fort Detrick Restoration Advisory Board Frederick, MD 

Gail Shephard Norwalk, CA 

Bruce Oldfield Professor, Geology Broome Community College Binghamton NY 

Bob Spiegel Executive Director Edison Wetlands Association Edison, NJ 

Robert Stewart Rural Community Assistance Project Washington DC 

Response: See response to comment code 6120. 

Commenter Name: Kathy Curtis 

Commenter Organization: Alliance of Nurses for Healthy Environments (ANHE) 

EPA Document ID: EPA-HQ-OW-2009-0297-0651 

EPA Comment ID: 28541 

EPA Comment Code: 6120 

 

Comment: October 7, 2009 

Mr. Eric Burneson Office of Ground Water and Drinking Water Standards and Risks Management 

Division Environmental Protection Agency 1200 Pennsylvania Avenue, NW, Mailcode 2822T 

Washington, D.C. 20460 Re: Docket ID No. EPA-HQ-OW-2009-0297 

Dear Mr. Burneson, 

On behalf of The Alliance of Nurses for Healthy Environments, we are writing to express our belief 

that the potential health impacts from exposure to perchlorate through drinking water are significant 

and that they call for prompt regulation to protect the public's health and safety. Setting a drinking 

water standard will provide the U.S. Environmental Protection Agency (EPA) with a "meaningful 

opportunity for health risk reduction for persons served by public water systems". EPA should 

move as quickly as possible to establish a more protective reference dose for perchlorate and then to 

promulgate a maximum contaminant level (MCL) for perchlorate that is no higher than one part per 

billion (ppb). 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 975 of 1099

Commenter Name: Kathy Curtis 

Commenter Organization: Alliance of Nurses for Healthy Environments (ANHE) 

EPA Document ID: EPA-HQ-OW-2009-0297-0651 

EPA Comment ID: 28546 

EPA Comment Code: 6120 

 

Comment: A perchlorate drinking water standard of no higher than 1 ppb would protect a large 

share of the American population currently at risk. Given the scope of the perchlorate 

contamination nationally, the multiple exposure pathways and other environmental contaminants 

impacting thyroid function and development, and the data demonstrating a serious health threat to a 

significant part of the country's population, we believe EPA is obligated to establish such a drinking 

water standard. We applaud the agency's consideration of how to move forward to regulate this 

contaminant and urge you to take steps to establish a protective MCL as soon as possible. 

We look forward to following the EPA response on this critical health issue. 

Sincerely, Kathy Curtis and MaryJane Williams, RN, PhD Co-chairs, Policy Workgroup For the 

Alliance of Nurses for Healthy Environments 

Response: See response to comment code 6120. 

Commenter Name: Rebecca O'Donnell 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0436 

EPA Comment ID: 28581 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion perchlorate, if that! 

Sincerely, Rebecca O'Donnell Boyertown, PA 

Response: See response to comment code 6120. 

Commenter Name: Raymond Sowiak 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0440 

EPA Comment ID: 28582 

EPA Comment Code: 6120 

 

Comment: I urge the EPA to adopt a limit of 1 PPBW perchlorate in U.S. drinking water. I 

understand recent studies show perchlorate to be more harmful than previously thought, especially 

to infants and young children. It may cause mental retardation, loss of hearing and speech, and poor 

development of motor skills. 

EPA's own data show perchlorate to be present in drinking water in 37 states, including public water 

systems serving more than 20 million people. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 976 of 1099

I understand that perchlorate, like any harmful chemical, probably affects different people to 

different degrees, but I also believe the EPA should err on the conservative side until more data can 

be amassed regarding the effects of these chemicals on a decent statistical basis. Big business will 

always have powerful advocates and lobbyists presenting gloomy scenarios of high costs and 

dubious benefits, but who advocates for the average guy here in the U.S.? 

Response: See response to comment code 6120. 

Commenter Name: Ron Harden 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0441 

EPA Comment ID: 28583 

EPA Comment Code: 6120 

 

Comment: It is imperative that our drinking water be protected in every possible way. It us 

unconsciensionable that perchlorate would be allowed to enter it, and unconsciensionable of an 

industry to seek to be able to place the compound in ground water. Please issue the appropriate 

regulation to disallow perchlorate from being placed into our water supplies. 

Response: Perchlorate is not being placed into water systems. EPA has decided to regulate 

perchlorate. See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0445 

EPA Comment ID: 28584 

EPA Comment Code: 6120 

 

Comment: Let's go! Complete this drinking water standard. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0446 

EPA Comment ID: 28585 

EPA Comment Code: 6120 

 

Comment: Please set limits for perchlorate in drinking water. It surprises me that it would even be 

considered not to have regulated and enforced standards to protect our citizens. 

Thank you! 

Response: See response to comment code 6120. 

Commenter Name: Eva 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0453 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 977 of 1099

EPA Comment ID: 28586 

EPA Comment Code: 6120 

 

Comment: Dear Trusted employees at Environmental Protection Agency of the USA, 

The citizens of this country trust you to analyze every single substance that comes at all in contact 

with our living environment, and to determine what amounts we can tolerate and still be healthy. 

We, including industry, needs to know that, so we can act accordingly.In your spare time you need 

to do that. But since you don't have any spare time ... then prioritize! and do the ones that are 

obvious first! 

Perchlorate is one of the very obvious ones that need to be done now! And please remember, that if 

you wait till a chemical is at the top of the priority list, then your analysis is more likely to be tainted 

by politics or industry pressures. It's better to get it done early, while no one is paying attention, so 

you can make a true impact analysis .... and please, always err on the side of human safety .... better 

to be safe than sorry. Thanks kindly ... we're counting on you to protect us. Eva in Denver, CO 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0466 

EPA Comment ID: 28589 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a primary 

drinking water standard for perchlorate that prioritizes potential and proven risks to public health 

and ecosystems over risks to industries that use perchlorate. 

Perchlorate is a harmful chemical that EPA claims has been found in 395 sites in 37 states, including 

153 public water systems serving over 20 million people. Some estimates are even higher. 

Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development and metabolism. Developing fetuses, infants and children with thyroid impairment 

may suffer mental retardation, loss of hearing and speech or deficits in motor skills. 

Response: See response to comment code 6120. 

Commenter Name: Daniel Sullivan 

Commenter Organization: Foil The Three Productions 

EPA Document ID: EPA-HQ-OW-2009-0297-0474 

EPA Comment ID: 28590 

EPA Comment Code: 6120 

 

Comment: Keep this perchlorate, this ingredient of rocket fuel, out of people's drinking water. 

Everyone has a right to be uncontaminated, especially children, who need to develop well. This stuff 

can retard their ability to build a good life in this changing world. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 978 of 1099

Commenter Name: Donna Cirillo 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0475 

EPA Comment ID: 28591 

EPA Comment Code: 6120 

 

Comment: To Whom It May Concern, 

I don't understand what the debate is about. We know that Perchlorate affects the thyroid, so limit 

it's usage. How many people need to be harmed before you take action? 

Very concerned citizen. Donna Cirillo 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0476 

EPA Comment ID: 28592 

EPA Comment Code: 6120 

 

Comment: Please take action to limit perchlorate in drinking water. 

Nobody wants rocket fuel in their drinking water. However, the U.S. Environmental Protection 

Agency (EPA) has still not decided whether to set a drinking water standard - a limit - for 

perchlorate, an ingredient in rocket fuel that is contaminating water nationwide. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0479 

EPA Comment ID: 28593 

EPA Comment Code: 6120 

 

Comment: Please Regulate our water more effectively and efficiently. 

Response: See response to comment code 6120. 

Commenter Name: Cici Hallberg 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0481 

EPA Comment ID: 28594 

EPA Comment Code: 6120 

 

Comment: Please keep perchlorate out of our drinking water. It has been determined to be 

carcinogenic. We don't need any more contaminates in our drinking water. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 979 of 1099

Response: See response to comment code 6120. 

Commenter Name: Belina Reisman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0483 

EPA Comment ID: 28595 

EPA Comment Code: 6120 

 

Comment: Please protect us from another pollutant. Please set limits on percholate in our water. 

Just today, I've come across two items that highlight our need to keep water safe and available, 

which requires regulatiion. 

The first, a news article, addressed peoples' need for dental work due to the damaging pollutants in 

the water. 

The second was a documentary shown on TV - Flow: For the Love of Water. I came away from the 

show recognizing we need to work now for protection of our water resources. 

Then, Clean Water Action sent me an email on the percholate issue. 

Response: See response to comment code 6120. 

Commenter Name: Lynn surname not provided 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0487 

EPA Comment ID: 28596 

EPA Comment Code: 6120 

 

Comment: Please make sure that percholate does not get into our water.It affects everyone. Keep 

us safe. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0488 

EPA Comment ID: 28597 

EPA Comment Code: 6120 

 

Comment: Please remain true to your name: the Environmental Protection Agency. That means 

something. This is not a conditional protection you offer, as in when you get special interest money 

to loosen controls, etc. You are charged with protecting the environment UNCONDITIONALLY. 

Please do your job. Keep our drinking water clean. Keep perchlorate out. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 980 of 1099

Commenter Name: Keitha Kinne 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0489 

EPA Comment ID: 28598 

EPA Comment Code: 6120 

 

Comment: I strongly urge the U.S. Environmental Protection Agency to move forward with a 

drinking water standard of no higher than 1 part per billion for perchlorate. For too long we have 

put the interest of unbridled growth ahead of the health of our people and our environment. We 

must recognize that we cannot continue down this path and the EPA must become a strong voice 

for preserving our environment. 

It is evident that perchlorate contamination is a nationwide problem and has health impacts at lower 

levels than previously thought; protecting infants and children is critical. A national primary drinking 

water regulation would provide a meaningful opportunity to protect public health. 

Please take this important step to limit perchlorate contamination. Respectfully yours. Keitha Kinne, 

129 Picketts Ridge Road, Redding CT 06896 

Response: See response to comment code 6120. 

Commenter Name: William Connor 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0490 

EPA Comment ID: 28599 

EPA Comment Code: 6120 

 

Comment: Please prohibit perchlorate out of potable water. Thank you 

Response: See response to comment code 6120. 

Commenter Name: Sasha Rickard 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0503 

EPA Comment ID: 28601 

EPA Comment Code: 6120 

 

Comment: Dear EPA, 

I am strongly in favor of puting a standard of no more than 1 part per billion for perchlorate as it is 

a risk to public health. 

Sincerely, Sasha Rickard 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 981 of 1099

EPA Document ID: EPA-HQ-OW-2009-0297-0508 

EPA Comment ID: 28602 

EPA Comment Code: 6120 

 

Comment: I ask you, please, U.S. Environmental Protection Agency, to put a limit on the amount 

of perchlorate in our drinking water to no higher than 1 part per billion. 

The public, of all ages, deserves to have their health protected by drinking water that does not cause 

health problems. If we as citizens do not have our health, we do not have much at all. 

Response: See response to comment code 6120. 

Commenter Name: Barbara Mc Ellen 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0512 

EPA Comment ID: 28603 

EPA Comment Code: 6120 

 

Comment: iam a single voter in bergen county new jersey who is recovering from cancer. please get 

the pollutants out of our water..including rocket fuel!!!! 

Response: See response to comment code 6120. 

Commenter Name: Ryan Tomazin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0520 

EPA Comment ID: 28605 

EPA Comment Code: 6120 

 

Comment: I am an environmental protection science/chemistry graduate, and I constantly argued 

with professors, guests from ALCOSAN in Pittsburgh and everyone else that would listen about 

chemical levels in water and what was acceptable in drinking water. Water is essential to all life, and 

there should not be an acceptable level of rocket fuel in water. There should be NO rocket fuel, or 

PCBs or heavy metals, etc., in our water. The water authorities should not have to super- chlorinate 

our water, like it is in Pittsburgh, to give us something that is essential to our life. Stand up and be 

the Environmental Protection Agency, and not the Chemical Subsidiaries Protection Agency. You 

were supposed to be on our side. How many cancer deaths do we have in the US, compared to 30 

or 50 years ago? Clean air and water is necessary, not optional. We are paying you, and this is what 

we want. 

Thank you for your time, 

Ryan Tomazin Bridgeville, PA 

Response: See response to comment code 6120. 

Commenter Name: Alexandra Grabbe 

Commenter Organization: Chez Sven Bed & Breakfast 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 982 of 1099

EPA Document ID: EPA-HQ-OW-2009-0297-0524 

EPA Comment ID: 28606 

EPA Comment Code: 6120 

 

Comment: I run a green bed & breakfast in Wellfleet on Cape Cod and often comment about the 

state of water on our fragile sandbar. I am very worried about percholorate in water supplies, since I 

have traveled on airplanes that dumped rocket fuel into the ocean, and sincerely hope you will do 

something to control percholorate. Please set a standard and improve regulations regarding drinking 

water in general. Thank you for your attention. 

Response: See response to comment code 6120. 

Commenter Name: Kathy Dolan 

Commenter Organization: Food and Water Watch (FWW) 

EPA Document ID: EPA-HQ-OW-2009-0297-0526 

EPA Comment ID: 28607 

EPA Comment Code: 6120 

 

Comment: Dear Administrator Jackson, 

Attached you will find an official statement from Food and Water Watch regarding EPA-HQ-OW2009-0297. Additionally, we have included over 6,000 activist letters supporting our statement. 

We urge you to make a national primary drinking water rule for perchlorate. EPA's failure to 

regulate perchlorate in drinking water places consumers, especially children and pregnant women, at 

risk. We recommend that EPA use the regulation of perchlorate as an opportunity to protect our 

waterways and make our drinking water safe for all. 

Thank you for your consideration, 

Kathy Dolan Triclosan Campaign Advocate Food and Water Watch 

 Attachment 

Administrator Jackson USEPA Headquarters Ariel Rios Building 1200 Pennsylvania Avenue, N. W. 

Washington, DC 20460 

September 18, 2009 

 Dear Administrator Jackson, 

I am writing, on behalf of Food and Water Watch, to urge you to make a national primary drinking 

water rule for perchlorate. 

Response: See response to comment code 6120. 

Commenter Name: Kathy Dolan 

Commenter Organization: Food and Water Watch (FWW) 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 983 of 1099

EPA Document ID: EPA-HQ-OW-2009-0297-0526 

EPA Comment ID: 28612 

EPA Comment Code: 6120 

 

Comment: The widespread exposure of the population to some level of perchlorate raises serious 

health concerns. Perchlorate can inhibit the thyroid glands iodine uptake, potentially leading to 

hypothyroidism. Severe hypothyroidism during pregnancy can lead to abnormal fetal cognitive 

development, and even mild hypothyroidism during pregnancy is associated with subtle cognitive 

defects in children. Thus, perchlorate could alter fetal brain development, having lifelong cognitive 

effects for those affected. 

EPA's failure to regulate perchlorate in drinking water places consumers, especially children and 

pregnant women, at risk. We urge the EPA to consider the regulation of perchlorate as an 

opportunity to protect our waterways and make our drinking water safe for all. 

Sincerely, 

Kathleen Dolan Triclosan Campaign Advocate 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0535 

EPA Comment ID: 28613 

EPA Comment Code: 6120 

 

Comment: I have lived on the "space coast" for over 40 years. I have an immune illness and 

wonder how much all those launches and resulting rocket fuel in my air and water may have 

contributed to my chronic illness. I will never have good health again. I don't want others to go 

through this miserable life. We must clean our air and water and this includes getting perchlorate out 

of our environment. 

Response: See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #11 - Food and Water Watch 

EPA Document ID: EPA-HQ-OW-2009-0297-0526 

EPA Comment ID: 28614 

EPA Comment Code: 6120 

 

Comment: Administrator Jackson USEPA Headquarters Ariel Rios Building 1200 Pennsylvania 

Avenue, N. W. Washington, DC 20460 

September 18, 2009 

 Dear Administrator Jackson, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 984 of 1099

I am writing, on behalf of Food and Water Watch, to urge you to make a national primary drinking 

water rule for perchlorate. 

Perchlorate has been found in the drinking water supply of 35 states and the District of Columbia. 

Widespread human exposure to perchlorate was confirmed by the Center for Disease Control's 

NHANES study, which found that 100 percent of the 2,820 randomly selected study participants 

had detectable levels of perchlorate in their urine. And according to your request for comment 

notice, dated August 5, 2009, the number of people served by water contaminated with high levels 

of perchlorate ranges between 53.4 and 16.8 million people. 

Response: See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #11 - Food and Water Watch 

EPA Document ID: EPA-HQ-OW-2009-0297-0526 

EPA Comment ID: 28618 

EPA Comment Code: 6120 

 

Comment: The widespread exposure of the population to some level of perchlorate raises serious 

health concerns. Perchlorate can inhibit the thyroid glands iodine uptake, potentially leading to 

hypothyroidism. Severe hypothyroidism during pregnancy can lead to abnormal fetal cognitive 

development, and even mild hypothyroidism during pregnancy is associated with subtle cognitive 

defects in children. Thus, perchlorate could alter fetal brain development, having lifelong cognitive 

effects for those affected. 

EPA's failure to regulate perchlorate in drinking water places consumers, especially children and 

pregnant women, at risk. We urge the EPA to consider the regulation of perchlorate as an 

opportunity to protect our waterways and make our drinking water safe for all. 

Response: See response to comment code 6120. 

Commenter Name: Mic Stewart 

Commenter Organization: Water Quality Section, Metropolitan Water District of Southern 

California 

EPA Document ID: EPA-HQ-OW-2009-0297-0496 

EPA Comment ID: 28710 

EPA Comment Code: 6120 

 

Comment: Metropolitan's Concerns 

Perchlorate contamination entering the Colorado River from the Las Vegas Wash area represents 

the largest extent of perchlorate contamination in the country. Water from the Colorado River 

downstream of the Las Vegas Wash supplies drinking water for over 23 million people throughout 

Nevada, California, and Arizona. Any effort to regulate perchlorate would ensure some degree of 

public health protection for this source of water supply. Metropolitan believes that federal regulation 

of perchlorate would provide a meaningful opportunity for health risk reduction for the public water 

systems as described in the Safe Drinking Water Act. 

Response: See response to comment code 6120. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 985 of 1099

Commenter Name: Mic Stewart 

Commenter Organization: Water Quality Section, Metropolitan Water District of Southern 

California 

EPA Document ID: EPA-HQ-OW-2009-0297-0496 

EPA Comment ID: 28714 

EPA Comment Code: 6120 

 

Comment: Since the 1996 amendments to the Safe Drinking Water Act, no new contaminant has 

met EPA's three criteria for national primary drinking water regulation. Metropolitan believes that a 

determination by EPA not to regulate perchlorate in drinking water could adversely influence 

cleanup efforts along the Colorado River and other contaminated sites. 

Metropolitan appreciates this opportunity to provide comments on scientific approaches to 

analyzing scientific data related to perchlorate in drinking water and requests that EPA carefully 

consider these comments. Please contact me at (213) 217-5696 if you have any questions, or if I can 

provide additional information. 

Very truly yours, Mic Stewart, Ph. D. Manager, Water Quality Section 

Response: See response to comment code 6120. 

Commenter Name: Nsedu O. Witherspoon 

Commenter Organization: Children's Environmental Health Network 

EPA Document ID: EPA-HQ-OW-2009-0297-0674 

EPA Comment ID: 28737 

EPA Comment Code: 6120 

 

Comment: The Network believes that the potential health impacts from exposure to perchlorate 

through drinking water are significant and that they warrant prompt regulation to protect public 

health and safety. Setting a drinking water standard will provide the U.S. Environmental Protection 

Agency (EPA) with a "meaningful opportunity for health risk reduction for persons served by public 

water systems". 

Consequently, EPA should move as quickly as possible to establish a more protective reference dose 

for perchlorate and then to promulgate a maximum contaminant level (MCL) for perchlorate that is 

no higher than one part per billion (ppb). We base this view on the scope of the contamination in 

drinking water supplies, exposure of the American population through other pathways, including 

food, and the most recent scientific studies that demonstrate serious health threats, even at low 

levels, to a larger portion of the population than previously recognized. These studies are based 

upon a much larger exposure data set than the studies upon which the current reference dose, and 

thus the entire regulatory regime, is based. 

Perchlorate has been found in more than 400 drinking water sources in 26 states, potentially 

affecting tens of millions of people. EPA’s own data say that nearly 17 million people receive their 

water from public water systems where perchlorate has been found at levels exceeding 4 ppb. Were 

sampling routinely conducted with a detection limit of 1 ppb, that number would be much higher-
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 986 of 1099

particularly considering the estimated 20 million people in the Southwest who receive drinking water 

from the Colorado River. 

Response: See response to comment code 6120. 

Commenter Name: Nsedu O. Witherspoon 

Commenter Organization: Children's Environmental Health Network 

EPA Document ID: EPA-HQ-OW-2009-0297-0674 

EPA Comment ID: 28742 

EPA Comment Code: 6120 

 

Comment: A perchlorate drinking water standard of no higher than 1 ppb would protect a large 

share of the American population currently at risk. Given the scope of the perchlorate 

contamination nationally, the multiple exposure pathways and other environmental contaminants 

impacting thyroid function and development, and the data demonstrating a serious health threat to a 

significant part of the country's population, EPA is obligated to establish such a drinking water 

standard. We applaud the agency’s consideration of how to move forward to regulate this 

contaminant and urge you to take steps to establish a protective MCL as soon as possible. 

Sincerely, 

Nsedu O. Witherspoon, MPH Executive Director 

Response: See response to comment code 6120. 

Commenter Name: Dan Delventhal 

Commenter Organization: MowGreen.US 

EPA Document ID: EPA-HQ-OW-2009-0297-0270 

EPA Comment ID: 28758 

EPA Comment Code: 6120 

 

Comment: Folks, we have to be proactive and precautionary and stand up as stewards to protect 

the masses from poisons in the air and water we survive on. You know the links to disease and 

reproductive related compromises. It would retarded to fail to prevent retardation in future 

generations. Limit Perchlorate! 

Response: See response to comment code 6120. 

Commenter Name: Karen Ceci 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0287 

EPA Comment ID: 28759 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. Please give our children and their 

children a chance at a healthy life. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 987 of 1099

Karen Ceci 11 Chalfont Rd Chalfont, PA 18914 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0536 

EPA Comment ID: 28760 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. Perchlorate contamination is a 

nationwide problem and has health impacts. 

The US needs national primary drinking water regulations to protect public health not only from 

perchlorate but from chemicals used in hydraulic fracturing and other industrial practices currently 

unregulated as a result of the Bush administration. The EPA MUST take action NOW--what in the 

world are you waiting for? Surely in this administration the PEOPLE have rights to health? 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. Regarding the need for drinking water regulations for contaminants used in hydraulic 

fracturing and other industrial practices, a response is not necessary because it is outside of the 

scope of this action. 

Commenter Name: Rita Valent 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0547 

EPA Comment ID: 28761 

EPA Comment Code: 6120 

 

Comment: I can't think of any reason why perchlorate shouldn't be limited. Of course it should be 

limited...it's dangerous, it hurts people. What other reason do we need? 

Response: See response to comment code 6120. 

Commenter Name: John M. Huff 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0549 

EPA Comment ID: 28763 

EPA Comment Code: 6120 

 

Comment: I strongly request that the U.S. Environmental Protection Agency proceed with setting 

the drinking water standard for perchlorate at no higher than 1 part per billion, for the best interests 

of public health, particularly on behalf of infants and children. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Myrna Poticha 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 988 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0552 

EPA Comment ID: 28764 

EPA Comment Code: 6120 

 

Comment: Please act vigorously to curtail the level of perchlorate in drinking water. Our drinking 

water supplies should be maintained at the highest level of purity, and exotic substances such as 

perchlorate have no place there, unless and until they are absolutely proven to be safe.Myrna Poticha 

Colorado 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0559 

EPA Comment ID: 28766 

EPA Comment Code: 6120 

 

Comment: Rocket fuel: KEEP IT OUT OF OUR WATER SUPPLIES!!! 

Response: See response to comment code 6120. 

Commenter Name: Kevin Hammond 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0560 

EPA Comment ID: 28767 

EPA Comment Code: 6120 

 

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. 

perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; protecting infants and children is critical.a national primary drinking water 

regulation would provide a meaningful opportunity to protect public health. 

Although I am not sure if 1 ppb (part per billion) is a realistic level, the current level of air travel is 

only increasing warranting serious review of safe levels. We owe it to our children (and their's) to, at 

the very least, set a realistic regulatory level that is 1.) not cost-prohibitive, 2.) safe and 3.) 

maintainable. 

Thank you for attention to this matter. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0563 

EPA Comment ID: 28769 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 989 of 1099

EPA Comment Code: 6120 

 

Comment: Perchlorate, like all other man-made substances, should be filtered from all public water 

systems. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0567 

EPA Comment ID: 28770 

EPA Comment Code: 6120 

 

Comment: eriously limit perchlorate in water, please. Thank you. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0574 

EPA Comment ID: 28772 

EPA Comment Code: 6120 

 

Comment: please remove perchlorate from our drinking water keep our children safe from harm 

Response: See response to comment code 6120. 

Commenter Name: Carol Leventhal 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0583 

EPA Comment ID: 28773 

EPA Comment Code: 6120 

 

Comment: It is inconceivable that the United States water supply is contaminated by perchlorate, to 

a degree that threatens health and well being. Please reduce perchlorate in the water to no more than 

1 part per billion. 

Carol Leventhal 9219 Manchester Road Silver Spring, MD. 20901 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0584 

EPA Comment ID: 28774 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 990 of 1099

Comment: I urge the U.S. Environmental Protection Agency to move forward with a drinking 

water standard of no higher than 1 part per billion for perchlorate. * perchlorate contamination is a 

nationwide problem and has health impacts at lower levels than previously thought; protecting 

infants and children is critical. * a national primary drinking water regulation would provide a 

meaningful opportunity to protect public health. 

Recently, a defense analysis postulates that the world will be competing for water resources. in the 

light of this we cannot afford to further pollute our sources of fresh water with any more chemicals. 

Further we must hold the polluters responsible for any cleanup of known harmful chemicals in our 

water supplies. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0585 

EPA Comment ID: 28775 

EPA Comment Code: 6120 

 

Comment: Perchlorate in drinking water is a public health problem.Even in small amounts, it can 

impair the thyroid gland, which controls growth, development and metabolism. Developing fetuses, 

infants and children with thyroid impairment may suffer mental retardation, loss of hearing and 

speech or deficits in motor skills. 

I urge the U.S. Environmental Protection Agency to establish and enforce a drinking water standard 

for perchlorate of no higher than 1 part per billion. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0591 

EPA Comment ID: 28776 

EPA Comment Code: 6120 

 

Comment: Bearing in mind the mission the EPA should strive to fulfill: protecting our air, soil, and 

water......I implore you to determine how the perchlorate is contaminating our water and to stop it.If 

stopping it is too lofty a goal for now, please limit the amount we are unknowingly exposed to every 

day. That's why we have your department - to protect citizens. 

Response: See response to comment code 6120. 

Commenter Name: Cathy Ellis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0597 

EPA Comment ID: 28777 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 991 of 1099

Comment: I urge the Federal government to set a percolate standard of no more than 1 part per 

billion. Clean drinking water should be a right of every American. Contaminants hurt the smallest 

and weakest the most and can be very harmful to fetuses and infants. These helpless citizens need 

the government to protect them over before it protects the rights of corporate America. Cathy Ellis 

West Chazy, NY 

Response: See response to comment code 6120. 

Commenter Name: Jim Tate 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0607 

EPA Comment ID: 28779 

EPA Comment Code: 6120 

 

Comment: EPA: Please establish a standard for the volume of perchlorate permitted in our 

drinking water. And it should be extrememly low! Enough scientific data exist to convince EPA that 

perchlorate is hazardous to the health of anyone living in the US. 

Response: See response to comment code 6120. 

Commenter Name: Neeka Stanley 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0611 

EPA Comment ID: 28781 

EPA Comment Code: 6120 

 

Comment: I drink tap water and I don't want a dose of perchlorate with it! It's a ridiculous waste to 

buy bottled water- I need my tap water to be safe and clean. I urge the U.S. Environmental 

Protection Agency to move forward with a drinking water standard of no higher than 1 part per 

billion for perchlorate. I work with kids with special needs and see the constant strain it puts on the 

kids, their families, and our community as we care for these kids. We need to do everything we can 

to limit exposure to toxic chemicals that could lead to even more kids with special needs. Thank 

you. 

Response: See response to comment code 6120. 

Commenter Name: Joanne R. Hand 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0613 

EPA Comment ID: 28782 

EPA Comment Code: 6120 

 

Comment: As a concerned citizen and supporter of Clean Water action I want to express my 

concern that the EPA limit the levels of perchlorate in drinking water to a standard of no higher 

than 1 part per billion for perchlorate 

Joanne R. Hand 41 Gregory Terrace Bloomfield New Jersey 07003 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 992 of 1099

Response: See response to comment code 6120. 

Commenter Name: James Griffin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0618 

EPA Comment ID: 28783 

EPA Comment Code: 6120 

 

Comment: I am writing to condemn the idea of allowing perchlorate in drinking water. In 

considering standards for water purity I urge you disallow this carcinogen in our water. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0619 

EPA Comment ID: 28784 

EPA Comment Code: 6120 

 

Comment: However, the U.S. Environmental Protection Agency (EPA) has still not decided 

whether to set a drinking water standard - a limit - for perchlorate, an ingredient in rocket fuel that is 

contaminating water nationwide. 

Clean Water Action members can help make sure the EPA takes action to limit perchlorate in 

drinking water. 

On August 19, the U.S. Environmental Protection Agency (EPA) requested public comments 

related to setting a limit for perchlorate in drinking water. Last year EPA appeared poised to 

announce that it would not set a limit but is now reviewing scientific and other information to make 

a decision about moving forward with a regulation now. 

Why limit perchlorate? 

Perchlorate is a harmful chemical that EPA claims has been found in 395 sites in 37 states, including 

153 public water systems serving over 20 million people. Some estimates are even higher. 

Perchlorate, even in small amounts, can impair the thyroid gland, which controls growth, 

development and metabolism. 

Developing fetuses, infants and children with thyroid impairment may suffer mental retardation, loss 

of hearing and speech or deficits in motor skills. 

Sample Letter 

I urge the U.S. Environmental Protection Agency to move forward with a drinking water standard 

of no higher than 1 part per billion for perchlorate. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 993 of 1099

perchlorate contamination is a nationwide problem and has health impacts at lower levels than 

previously thought; protecting infants and children is critical.a national primary drinking water 

regulation would provide a meaningful opportunity to protect public health. 

Response: This is not a comment, a response is not needed. 

Commenter Name: Lucy Rogers 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0621 

EPA Comment ID: 28785 

EPA Comment Code: 6120 

 

Comment: Keep perchlorate out of our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Barbara B. Tacy 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0623 

EPA Comment ID: 28786 

EPA Comment Code: 6120 

 

Comment: To Whom It May Concern; As an individual living in a highly populated area I am very 

aware of the critical need to protect what clean water we have left. Please act now to restrict the 

introduction of perchlorate into all of our water systems. Thank you, Dr. Barbara B. Tacy 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0624 

EPA Comment ID: 28787 

EPA Comment Code: 6120 

 

Comment: make this happen, we should not have to drink this 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0629 

EPA Comment ID: 28788 

EPA Comment Code: 6120 

 

Comment: I don't understand how it is acceptable for any perchlorate to be in any water in 

America. I do not feel that the government has the people's best interest in mind when they allow 

these chemicals into homes. During the presidential campaign, I noticed there was a lot of talk about 

preventative care for health. I feel this goes in with that. If we were to take care of the roots of 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 994 of 1099

sickness and disease, then the tree would die off as well. The government has a responsibility to the 

people of America, and I feel that it is about time that the government steps up and fulfills those 

responsibilities. 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0630 

EPA Comment ID: 28789 

EPA Comment Code: 6120 

 

Comment: I don't understand how it is acceptable for any amount of perchlorate to be in any water 

in America. During the presidential campaign, there was a lot of talk about preventative care. If we 

prevented the public from consuming harmful chemical, we would also be preventing the public 

from becoming ill. The government has a responsibility to the American people. I think it is about 

time the government steps up and fulfills those responsibilities. 

Response: See response to comment code 6120. 

Commenter Name: Brad Heinz 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0631 

EPA Comment ID: 28790 

EPA Comment Code: 6120 

 

Comment: From 1962-1977, I was raised in West Covina, California, a city whose drinking water 

supply was later determined to be contaiminiated by perchlorate. In late 1977, after I left for college, 

I was diagnosed with thyroid disease. The disease made it very difficult to pursue my studies, forcing 

me to drop classes. It also significantly intefered with my social integration during my freshman year. 

When later I learned about the contamination of the water supply in West Covina, I was angry to 

think how that might have contributed to the disease. It wrecked my life for the period leading up to 

diagnosis and treatment. I'm still concerned about the longterm health effects. Please strictly regulate 

this chemical in our drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28792 

EPA Comment Code: 6120 

 

Comment: September 19, 2009 

U.S. Environmental Protection Agency Office of Water Docket (Mailcode: 2822T) 1200 

Pennsylvania Avenue, NW Washington, DC 20460 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 995 of 1099

Submitted via www.regulations.gov 

 Comments from the NATURAL RESOURCES DEFENSE COUNCIL 

on the Drinking Water: Perchlorate Supplemental Request for Comments 

Docket EPA-HQ-OW-2009-0297 Federal Register / Vol. 74, No. 159/ Wednesday, August 19, 

2009 

SUMMARY 

On August 19, 2009, the U.S. Environmental Protection Agency (EPA) issued a Federal Register 

(FR) notice[FN1: 74 Fed. Reg. 41883 (August 19, 2009).] requesting comments on additional 

approaches to analyzing data related to its perchlorate preliminary determination as detailed in its 

October 10, 2008 FR Notice.[FN2: 73 Fed. Reg. 60262 (October 10, 2008).] In that previous notice, 

EPA made a preliminary regulatory determination not to set a health-protective standard for 

perchlorate in drinking water.[FN3: Id.] It stated, "The Agency has determined that a national 

primary drinking water regulation (NPDWR) for perchlorate would not present 'a meaningful 

opportunity for health risk reduction for persons served by public water systems.'" EPA also 

proposed a health reference level (HRL) of 15 parts per billion (ppb) as the maximum 

contamination level of perchlorate that could be in drinking water and still keep daily human 

consumption levels from exceeding the reference dose (RfD) of 0.7 ug/kg/day. 

In response to the October 10, 2008 FR notice, NRDC provided comments to EPA concluding that 

EPA's determination was legally flawed. EPA must regulate a contaminant if it may have an adverse 

effect on human health, if it is known to occur (or there is a substantial likelihood that the 

contaminant will occur) in public water systems with a frequency and at levels of public health 

concern; and if its regulation would present a meaningful opportunity for health risk reduction for 

persons served by public water systems.[FN4: 42 U.S.C. [Sec] 300g-1(b)(1)(A).] For perchlorate, each 

of these three requirements are met, and therefore, underscore the need for EPA to regulate its 

presence in drinking water. First, EPA's preliminary regulatory determination acknowledges that 

perchlorate may adversely affect human health.[FN5: 73 Fed. Reg. 60275 (Oct. 10, 2008).] Second, 

as explained in more detail below, despite EPA's contention, perchlorate is known to contaminate 

the drinking water systems serving millions of people at levels where adverse human health effects 

occur. And third, setting an appropriately stringent MCL will lead to lower levels of perchlorate 

ingested by hundreds of thousands of infants, children, and pregnant women, thereby offering a 

concrete and meaningful reduction in human health risks. 

The U.S. population is about 300 million people with about 6.8%, or 20 million, under 5 years old. 

Therefore, based on EPA estimates that 16.6 million people are served by public water system with 

at least one detection of perchlorate over 4 ppb, there are, therefore, likely more than one million 

children in each year of life (from zero to five) who may be exposed to perchlorate levels that may 

adversely affect their health.[FN6: This value is derived by multiplying 16.6 million by 0.068. Please 

see below for further explanation about the appropriate perchlorate level to set for the health 

reference level.] Thus, the evidentiary record does not support EPA's proposed determination. 

Rather, the evidentiary record makes clear that regulating these exposures do represent "a 

meaningful opportunity for health risk reduction for persons served by public water systems." 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Based upon the evidence in the record, as discussed in greater detail below, NRDC urges EPA to 

reverse course, and set a national primary drinking water standard for perchlorate that is protective 

of sensitive sub-populations. EPA should not set a HRL at 15 ppb; rather, given the most current 

data available, NRDC believes that to truly protect the public health, EPA should set an enforceable 

maximum contaminant level (MCL) as authorized by the Safe Drinking Water Act below 1 ppb. 

Response: See response to comment code 6120. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28796 

EPA Comment Code: 6120 

 

Comment: NRDC strongly objected to EPA's preliminary determination not to regulate perchlorate 

because the conclusions are not based on a comprehensive review of the best available science (as 

explained in more detail below) and are not supported by the PBPK model findings, or by EPA's 

expert scientific advisors on the Children's Health Protection Advisory Committee.[FN23: Letter 

from Melanie Marty to Administrator Johnson regarding Preliminary Regulatory Determination on 

Perchlorate (November 3, 2008, PDF) 

http://yosemite.epa.gov/ochp/ochpweb.nsf/content/perchlorateletter.htm/$file/Per 

chlorateLetter.pdf] In fact, drinking water that is contaminated with perchlorate at the proposed 

HRL of 15 ppb would leave infants and young children exposed to excessive and unsafe levels of 

this toxic chemical. 

Response: See response to comment ID 20988 under comment code 6120. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28812 

EPA Comment Code: 6120 

 

Comment: ADDITIONAL COMMENTS 

Regulating Perchlorate Represents a Meaningful Opportunity for Health Risk Reduction 

NRDC notes that there is enough information for the Agency to make a final regulatory 

determination to promulgate a national primary drinking water standard for perchlorate. The 

evidence about the impact of perchlorate contaminated drinking water shows that it satisfies the 

requirements for promulgating a drinking water standard under the Safe Drinking Water Act: (1) 

perchlorate is know to have an adverse effect on the health of persons; (2) perchlorate is known to 

occur in public water systems with a frequency and at levels of public health concern, and (3) 

regulating perchlorate presents a meaningful opportunity for health risk reduction for persons 

served by public water systems. Therefore, EPA should set an MCL for perchlorate, rather than 

focus on setting an HRL. 
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In its October 10, 2008 preliminary determination not to regulate perchlorate, EPA acknowledged 

that perchlorate could have an adverse effect on human health.[FN65: 73 Fed. Ref. at 60275.] 

Second, based on just quarterly or semi- annual sampling along, EPA showed that 4 percent of 

drinking water systems have detections of perchlorate over 4 ppb. As explained in further detail 

below, this occurrence exposes hundreds of thousands of pregnant women, children, and infants to 

dangerous levels of perchlorate, giving rise to a public health concern. 

In October, 2008, EPA determined that up to 28,000 pregnant women would be exposed to more 

than 15 ppb of perchlorate. However, at that time, EPA stated that reducing the risk that 28,000 

pregnant women would be exposed to perchlorate would not provide a meaningful opportunity to 

reduce health risks. 

What that October 2008 announcement failed to explain is that EPA's own staff experts have 

provided data to show that at the proposed HRL of 15 ppb, infants and children would consume 

perchlorate on a daily basis that exceeded the reference dose. 

As explained above, EPA's proposed model shows that there are over one million children under 5 

years old who would exceed the daily reference dose; this is likely an underestimate of the highly 

exposed. 

As noted above, NRDC believes that any amount of perchlorate in drinking water over 1 ppb may 

have adverse health impacts on vulnerable populations, meaning EPA's estimate of the number of 

pregnant women who would be exposed to excessive perchlorate would be much higher than 

28,000. In fact, based on EPA's estimate, over 200,000 pregnant women could be exposed to 

perchlorate contamination over 4 ppb (the maximum detection limit identified in EPA's estimates). 

As such, by any measure, a regulation that could protect up to over 200,000 pregnant women and a 

million children and infants would give rise to a meaningful opportunity to protect public health. 

Response: See response to comment code 6120. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28816 

EPA Comment Code: 6120 

 

Comment: CONCLUSION 

EPA should amend its preliminary determination on perchlorate. EPA should determine to 

promulgate a national primary drinking water standard for perchlorate, to protect public health. 

Existing data on perchlorate exposure and effects, especially on vulnerable subpopulations, 

demonstrates that setting a national primary drinking water standard for perchlorate would provide a 

meaningful opportunity for health risk reduction. EPA is therefore required to set such a standard 

under the Safe Drinking Water Act. 

Furthermore, a maximum contaminant level below 1 ppb would afford reasonable protections to the 

health of the susceptible populations of pregnant women and breast-fed infants. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Response: See response to comment code 6120. 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0527 

EPA Comment ID: 28908 

EPA Comment Code: 6120 

 

Comment: NJ Environmental Protection's comment. 

If problem looking, please call 609-292-5550, Heather Hansberry 

Attachment 

 September 18, 2009 

Water Docket Environmental Protection Agency Mail Code: 2822T 1200 Pennsylvania Ave, NW 

Washington, DC 20460 RE: Docket ID No. EPA-HQ-OW-2009-0297 

To Whom It May Concern: 

Thank you for the opportunity to provide comments on USEPA's notice, "Drinking Water: 

Perchlorate Supplemental Request for Comments," which was published in the Federal Register of 

August 18, 2009 (74 Fed. Reg. 41883-41893). On March 16, 2009, the New Jersey Department of 

Environmental Protection (NJDEP) proposed a drinking water Maximum Contaminant Level 

(MCL) of 5 ug/L, including monitoring and compliance determination requirements, in accordance 

with the 2005 recommendation of the New Jersey Drinking Water Quality Institute (NJDWQI), a 

legislatively created advisory body. The NJDEP believes that having an MCL for perchlorate will be 

beneficial to public health both in New Jersey and in the country as a whole. 

In comments submitted on November 10, 2008, we urged USEPA to reconsider its October 10, 

2008 proposed determination to not regulate perchlorate in drinking water. Our comments stressed 

that USEPA's proposed Health Reference Level (HRL) of 15 ug/L is not protective of infants, who 

are a sensitive population for perchlorate's effects on thyroid function. We also commented that the 

occurrence analysis presented was flawed because its use of an inappropriately high concentration, 

15 ug/L, greatly reduced the size of the population predicted to be exposed at levels of public health 

concern. We commend USEPA for its current decision to reconsider its proposal not to regulate 

perchlorate, based on the comments submitted by us and by many others. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0527 

EPA Comment ID: 28917 

EPA Comment Code: 6120 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 999 of 1099

Comment: We also strongly urge USEPA to reconsider its determination to not regulate 

perchlorate. The NJDEP (2009) proposed rule regarding the regulation of perchlorate in drinking 

water can be found at http://www.nj.gov/dep/rules/proposals/031609a.pdf. The New Jersey 

Drinking Water Quality Institute (2005) recommendations regarding perchlorate can be found at 

http://www.nj.gov/dep/watersupply/perchlorate_mcl_10_7_05.pdf. For further information or 

clarification about this issue, please contact Dr. Gloria Post at (609) 292-8497 or 

gloria.post@dep.state.nj.us. 

Sincerely, Jeanne Herb Director Policy, Planning and Science 

Scott Brubaker Acting Assistant Commissioner Land Use Management 

C : Gary Buchanan, NJDEP Judy Louis, NJDEP Sandra Krietzman, NJDEP Betty Boros-Russo, 

NJDEP Gloria Post, NJDEP Perry Cohn, NJDHHS Mark Robson, Chair, New Jersey Drinking 

Water Quality Institute 

Response: See response to comment code 6120. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group (EWG) 

EPA Document ID: EPA-HQ-OW-2009-0297-0499 

EPA Comment ID: 28926 

EPA Comment Code: 6120 

 

Comment: Attached are EWG's comments on Docket ID no. EPA-HQ-OW-2009-0297 (Drinking 

Water: Perchlorate Supplemental Request for Comments). Thank you. 

 September 18, 2009 

Mr. Eric Burneson Office of Ground Water and Drinking Water Standards and Risk Management 

Division Environmental Protection Agency 1200 Pennsylvania Avenue, NW Washington, DC 

20460 

Re: Docket ID no. EPA-HQ-OW-2009-0297 

Dear Mr. Burneson: 

The Environmental Working Group (EWG) strongly supports the Environmental Protection 

Agency (EPA) establishing a drinking water standard for the rocket fuel ingredient perchlorate. This 

compound contaminates drinking water supplies nationwide at levels of concern for human health, 

providing the agency with a meaningful opportunity for human health risk reduction through a 

national primary drinking water rule: 

- The EPA has reported finding perchlorate, a potent thyroid toxin, in public water systems in 28 

states and territories and estimated that nearly 17 million people may be served by public water 

systems with at least one perchlorate detection > 4 ppb - The Centers for Disease Control and 

Prevention (CDC) have found perchlorate in the urine of nearly 3,000 Americans who were tested 

as part of a national biomonitoring study, indicating widespread exposure among the U.S. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1000 of 1099

population (Blount et al 2006a) - In infants and children, drinking perchlorate contaminated tap 

water can result in cumulative exposures that exceed the EPA's reference dose (RfD), even at tap 

water concentrations as low as 1 part per billion (ppb). 

Recommendations 

- EPA's own analyses show that infants under six months of age are exposed to enough perchlorate 

via food that additional exposure to perchlorate via tap water concentrations as low as 1 ppb can 

result in combined exposures that exceed the RfD. To protect these highly vulnerable individuals, 

EPA must set an MCL of less than 1 ppb for perchlorate in drinking water. 

Response: See response to comment code 6120. 

Commenter Name: Anila Jacob 

Commenter Organization: Environmental Working Group (EWG) 

EPA Document ID: EPA-HQ-OW-2009-0297-0499 

EPA Comment ID: 28937 

EPA Comment Code: 6120 

 

Comment: Summary: There is a wealth of evidence from government and academic scientists that 

strongly suggests that infants and children not only have disproportionately high perchlorate 

exposure compared with adults, they are also more vulnerable to its toxic effects. Baseline 

perchlorate contamination of breast milk, powdered infant formula, and commonly consumed foods 

and beverages ensures that almost every infant and child in the U.S. will have multiple, daily sources 

of perchlorate exposure during critical periods of growth and brain development. However, for 

those children who live in states with perchlorate contamination of tap water, the additional 

exposure from the tap water can easily lead to cumulative exposures that exceed the agency's RfD. A 

decision by the agency to set an enforceable maximum contaminant level (MCL) of less than 1 ppb 

could benefit the health of millions of infants and children by decreasing cumulative perchlorate 

exposures. 

Sincerely, Anila Jacob, M.D., M.P.H. Senior Scientist 

Enc. Attachment 1 

References: 

Blount BC, Valentin-Blasini L, Osterloh JD, Mauldin JP, Pirkle JL. 2006a. Perchlorate exposure of 

the US population, 2001-2002. Journal of Exposure Science and Environmental Epidemiology 

17(4): 400-07. 

Blount BC, Pirkle JL, Osterloh JD, Valentin-Blasini L, Caldwell LK. 2006b. Urinary perchlorate and 

thyroid hormone levels in adolescent and adult men and women living in the United States. 

Environmental Health Perspectives 114(12): 1865-71. 

CHPAC (Children's Health Protection Advisory Committee). 2008. Letter from Melanie Marty to 

Administrator Johnson regarding Preliminary Regulatory Determination on Perchlorate. Available 

online at: http://74.125.155.132/search?q= 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1001 of 1099

cache:fgJhPl_tIOIJ:yosemite.epa.gov/ochp/ochpweb.nsf/content/perchlorateletter.h 

tm/%24File/PerchlorateLetter.pdf+CHPAC+and+perchlorate&cd=3&hl=en&ct=clnk&gl= 

us&client=firefox-a 

EPA (Environmental Protection Agency) 2008. Child-specific exposure factors handbook. Available 

online at: http://cfpub.epa.gov/ncea/CFM/recordisplay.cfm?deid=199243 

EWG. 2005. National tap water quality database. Available online at: 

http://www.ewg.org/tapwater/findings.php 

EWG. 2008. FDA food testing shows widespread rocket fuel contamination of commonly 

consumed foods and beverages. Available online at: http://www.ewg.org/reports/FDAFindsRocket-Fuel-(Perchlorate)-in-Food-and- Beverages 

GAO (U.S. Government Accountability Office). 2005. Perchlorate. A system to tract sampling and 

cleanup results is needed. GAO-05-462. 20 Available online at: 

www.gao.gov/new.items/d07797t.pdf 

GAO (U.S. Government Accountability Office). 2006. Breastfeeding. Some strategies used to 

market infant formula may discourage breastfeeding: state contracts should better protect against 

misuse of WIC name. GAO-06-282. Available online at: www.gao.gov/new.items/d06282.pdf 

Ginsberg G, Rice D. 2005. The NAS perchlorate review: questions remain about the perchlorate 

RfD. Environmental Health Perspectives 113(9): 1117-9. 

Ginsberg G, Hattis DB, Zoeller RT, Rice DC. 2007. Evaluation of the U.S. EPA/OSWER 

preliminary remediation goal for perchlorate in groundwater; focus on exposure to nursing infants. 

Environmental Health Perspectives 115(3): 361-69. 

Greer MA, Goodman G, Pleuss RC, Greer SE. 2002. Health Effect Assessment for Environmental 

Perchlorate Contamination: the Dose Response for Inhibition of Thyroidal Radioiodide Uptake in 

Humans. Environmental Health Perspectives (110): 927-37. 

Haddow JE, Palomaki GE, Allan WC, Williams JR, Knight GJ, Gagnon J, O'Heir CE, Mitchell ML, 

Hermos RJ, Waisbren SE, Fair JD, Klein RZ. 1999. Maternal thyroid deficiency during pregnancy 

and subsequent neuropsychological development of the child. New England Journal of Medicine 

341: 549-555. 

Kirk AB, Martinelango PK, Tian K, Dutta A, Smith EE, Dasgupta PK. 2005. Perchlorate and iodide 

in dairy and breast milk. Environmental Science and Technology 39: 2011- 2017. 

Kirk AB, Dyke JV, Martin CF, Dasgupta K. 2007. Temporal patterns in perchlorate, thiocyanate, 

and iodide excretion in human milk. Environmental Health Perspectives 115: 182-186. 

MassDEP. 2006. Update to "Perchlorate Toxicological Profile and Health Assessment". 

http://www.mass.gov/portal/gog_cache.jsp?q=cache:DvvnPHJtRYwJ:www.mass.gov/dep 

/toxics/perchlorate-toxicity-061206.pdf+Greer&access=p&output=xml_no_dtd&ie=UTF8&client=mgov&site=EOEAxDEPx&proxystylesheet=mgov&oe=UTF-8 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1002 of 1099

Meikle A. Endocrine Replacement Therapy in Clinical Practice. New York: Springer-Valley, 2007. 

Murray WM, Egan SR, Kim H, Beru N, Bolger PM. 2008. US Food and Drug Administration's 

Total Diet Study: Dietary intake of perchlorate and iodine. Journal of Exposure Science and 

Environmental Epidemiology 2008 (1-10)Epub ahead of print. 

NAS (National Academy of Sciences). 2005. Health Implication of Perchlorate Ingestion. National 

Academies Press. Available online at: http://www.nap.edu/catalog.php?record_id=11202 

Pearce EN, Leung AM, Blount BC, Bazrafshan HR, He X, Pino S, Valentin-Blasini L, Braverman 

LE. 2007. Breast milk iodine and perchlorate concentrations in lactating Boston area women. 

Journal of Clinical Endocrinology and Metabolism epub Feb 2007. 

Pop VJ, Kuijpens JL, van Baar AL, Verkerk G, van Son MM, de Vijider JJ, Vulsma T, Wiersinga 

WM, Drexhage HA, Vader HL. 1999. Low maternal free thyroxine concentrations during early 

pregnancy are associated with impaired psychomotor development in early infancy. Clinical 

Endocrinology 50: 149-55. 

Schier JG, Wolkin AF, Valentin-Blasini L, Belson MG, Kieszak SM, Rubin CS, Blount BC. 2009. 

Perchlorate exposure from infant formula and comparisons with the perchlorate reference dose. 

Journal of Exposure Science and Environmental Epidemiology, March 18 (Epub ahead of print). 

Steinmaus C, Miller MD, Howd R. 2007. Impact of smoking and thiocyanate on perchlorate and 

thyroid hormone associations in the 2001-2002 national health and nutrition examination survey. 

Environmental Health Perspectives 115(9): 1333-8. 

WHO (World Health Organization and Food and Agriculture Organization). 1998. Vitamin and 

mineral requirements in human nutrition. Second edition. Available online at: 

http://whqlibdoc.who.int/publications/2004/9241546123.pdf 

Attachment 1: 

Centers for Disease Control and Prevention's Responses to Questions for the Record From House 

Committee on Energy and Commerce 

Response: See response to comment code 6120. 

Commenter Name: Apparent Mass Mailing #9 - Group Unidentified) 

EPA Document ID: EPA-HQ-OW-2008-0692-2366 

EPA Comment ID: 29116 

EPA Comment Code: 6120 

 

Comment: Water Docket, EPA, Mailcode 2822T 1200 Pennsylvania Ave., NW Washington, DC 

20460 

To Whom It May Concern: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1003 of 1099

I urge you to reverse your decision and set a federal limit for perchlorate in drinking water. 

Perchlorate is a nationwide problem and has health impacts at lower levels than previously thought. 

Please protect public health, especially infants and children, by regulating perchlorate. 

Response: Please see the response to comment code 6120. 

Revisions: Page 3 (Comment ID 20759) 

 
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EPA Comment Code: 6125 Comments critical of preliminary determination (in 

the October 2008 FR Notice) specific to Washington Post article 

Individual Comments 

Commenter Name: J Richards 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0223 

EPA Comment ID: 19835 

EPA Comment Code: 6125 

 

Comment: from Washington Post article 

Last month, The Washington Post reported that White House officials had extensively edited the 

EPA's perchlorate rule-making documentation to remove scientific data highlighting some of the 

risks associated with the chemical, which has been found in water in 35 states. The Defense 

Department and Pentagon contractors who face legal liability stemming from rocket fuel 

contamination have lobbied for six years to avoid a federal drinking-water standard for perchlorate. 

http://www.washingtonpost.com/wp- dyn/content/article/2008/10/03/AR2008100303280.html? 

nav=rss_business/government 

This appears to be not only a medical but a political-moral issue. 

Response: Please see the response to comment code 6110. EPA has reversed its October 2008 

preliminary determination not to regulate perchlorate based upon a more direct evaluation of 

exposure to infants and developing children. In making today’s final regulatory determination, EPA 

uses the criteria mandated by the 1996 SDWA Amendments. EPA has made its determination based 

upon a consideration of the best available peer reviewed science and data collected in accordance 

with accepted methods. 

Commenter Name: Mary Beth Sullivan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0370 

EPA Comment ID: 19844 

EPA Comment Code: 6125 

 

Comment: The Washington Post reported that "The GAO, which produced a 2005 report calling 

for a better federal tracking system for perchlorate, found that limited EPA data show the chemical 

compound has polluted the soil, groundwater and drinking water in 35 states and the District and 

has contaminated 153 public water systems in 26 states." The fact that there are some infants and 

toddlers in this country who drink formula using water contaminated by perchlorate is sinful. I have 

thyroid disease. I know how sluggish and foggy my mind becomes. I know how hard this disease is 

to diagnose. 

We spend so many dollars on the military and "homeland security" to keep Americans "safe" from 

enemies. This perchlorate story is an example of the enemy within. The Washington Post also 

reports that, "A National Academy of Sciences panel prepared a risk analysis in 2005 that...came 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1005 of 1099

under attack because two of the committee's members had financial ties to defense contractors that 

face legal liability because of perchlorate disposal." It seems to me that military contractors run this 

country. We know they hand out big bucks to decision makers to prevent creating regulation 

requiring them to clean up the mess they make. 

Response: Please see the response to comment code 6110. EPA has reversed its October 2008 

preliminary determination not to regulate perchlorate based upon a more direct evaluation of 

exposure to infants and developing children. In making today’s final regulatory determination, EPA 

uses the criteria mandated by the 1996 SDWA Amendments. EPA has made its determination based 

upon a consideration of the best available peer reviewed science and data collected in accordance 

with accepted methods. 

Commenter Name: Meghan Hendy 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1874 

EPA Comment ID: 20759 

EPA Comment Code: 6125 

 

Comment: As reported in the Washington Post on September 22, 2008: 

In the EPA's proposed rule, the administration assumes that perchlorate contamination of 15 ppb is 

safe. But its regulatory document states that "between 16,000 and 28,000 pregnant women" and 

900,000 to 2 million Americans could be exposed to higher levels. The EPA document also finds 

that bottle-fed infants would be exposed to more than five times the level the National Academy of 

Sciences deemed safe -- 700 nanograms per kilogram of body weight per day -- if parents mix 

formula with drinking water containing perchlorate levels of 15 ppb. 

Response: Please see the response to comment code 6110. EPA has reversed its October 2008 

preliminary determination not to develop an NPDWR for perchlorate and now concludes, based on 

the analysis presented in this notice, that there is a substantial likelihood that perchlorate will occur 

in public water systems with a frequency and at levels of public health concern. Finally, EPA has 

determined that regulation of perchlorate presents a meaningful opportunity to reduce health risk 

for persons served by public water systems. EPA is initiating the development of a proposed 

NPDWR for perchlorate. 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 6130 Miscellaneous comments on the preliminary 

determination not to regulate (in the October 2008 FR Notice) 

Individual Comments 

Commenter Name: David Sparling, M.D., F.A.A.P. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0135 

EPA Comment ID: 19722 

EPA Comment Code: 6130 

 

Comment: 2) The sources of perchlorate contamination of those public drinking water supplies 

should be identified and plans developed for decontamination of these sources or the development 

of alternative water supply sources not contaminated with perchlorate. 

David Sparling, M.D., F.A.A.P. P.O. Box 88637 Steilacoom, WA 98388 

dsparling@igc.org 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. EPA will seek comment on any specific regulatory requirements as part of a proposed 

national primary drinking water regulation. 

Commenter Name: Ed Thomas 

Commenter Organization: National Rural Water Association (NRWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0163 

EPA Comment ID: 20273 

EPA Comment Code: 6130 

 

Comment: Finally, NRWA feels that the issues raised by the aforementioned papers are of 

sufficient importance that it would be premature for the Agency to proceed with any of the possible 

scenarios for arriving at a perchlorate determination until these issues are resolved. For example, it is 

pointed out in the discussion of the evaluation of occurrence data and populations exposed (Table 5, 

page 24047) that this evaluation is very sensitive to the choice of an RSC and presumably to the 

occurrence data also. If the existing levels of contaminants are not known to any better accuracy 

than plus or minus a factor of 2 or more as is suggested by reference 1 above, it would not be good 

science to proceed with an analysis that is known to be sensitive to the value of such numbers. 

Further we would encourage the agency to continue using and collecting data to support a 

"meaningful opportunity for public health protection" when determining if there is a clear benefit of 

regulating perchlorate. It is NRWA's belief that there is a need for more data to support this 

determination. There remain many uncertainties about the relative source contribution and the levels 

of perchlorate in urinary excretions. We believe that these issues along with the issues of 

affordability and compliance data variability must be appropriately addressed prior to the EPA 

Administrator making a determination regarding perchlorate, in accordance with Section 

1412(b)(1)(A) of the 1996 SDWA Amendments, that "in the sole judgment of the Administrator, 

regulation of such contaminant presents a meaningful opportunity for health risk reduction for 

persons served by public water systems." 
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We thank you for the opportunity to provide comments regarding this important matter. 

Sincerely, Ed Thomas Ed Thomas 

 Electronic Attachments: 1. Phillips compliance data variability final.pdf 2. Rubin trade off health 

risk final.pdf 

Response: EPA has made its determination based upon a consideration of the best available peer 

reviewed science and data collected in accordance with accepted methods related to perchlorate 

occurrence in drinking water, the presence of perchlorate in foods, and the health effects of 

exposure to perchlorate. Regarding the comment encouraging EPA to collect additional data to 

support the determination and to consider the papers the commenter provided, EPA believes there 

are sufficient data on which to evaluate the best available data to make the determination. EPA does 

not believe that affordability analysis is needed to make a regulatory determination. SDWA requires 

that EPA evaluate affordability for small systems and request comment at the time of proposing a 

national primary drinking water standard. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: AMWA 

EPA Document ID: EPA-HQ-OW-2008-0692-1525 

EPA Comment ID: 20444 

EPA Comment Code: 6130 

 

Comment: National Academy of Sciences Review 

In 2003, EPA asked the National Research Council (NRC) of the NAS to: * Assess the current state 

of the science regarding potential adverse effects of disruption of thyroid function by perchlorate 

and * Determine whether EPA's findings in its 2002 draft risk assessment were appropriate. 

AMWA believes that regardless of the outcome of the final determination on perchlorate, the 

agency should commit to placing a similar question before the NAS for an answer by 2011. 

If EPA’s final decision is to regulate perchlorate, then the review of the science available since the 

2005 NAS report should provide a good foundation on which to build a regulation. If the decision is 

not to regulate perchlorate for the present, then the review will either confirm the decision with 

respect to changes in the state of scientific knowledge or possibly point to the need to reassess the 

HRL and the regulatory determination. 

Retention on the CCL 

AMWA recommends that perchlorate be retained on the CCL or that some similar but less formal 

administrative action be taken so that changes in the science speaking to potential health effects and 

changes in occurrence continue to be captured and evaluated. AMWA recommends that in the final 

determination, EPA elaborate on how systems such as IRIS are used to keep risk and other 

pertinent contaminant information current and how it might be used to advantage in tracking any 

changes in perchlorate status. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1008 of 1099

Response: The Agency believes that a second review by the NAS would unnecessarily delay 

regulatory decision making for perchlorate. Therefore, EPA did not request additional NRC review 

of issues related to perchlorate. EPA has assessed recent best available data and has determined that 

regulation of perchlorate in drinking water systems presents a meaningful opportunity to reduce 

health risk for persons served by public water systems and has decided to regulate perchlorate in 

drinking water. See response to comment code 6120. 

Regarding your recommendation that EPA ensure that changes in science related to potential health 

effects and changes in occurrence continue to be captured and evaluated, and elaborate on how 

systems such as IRIS are used to keep risk and other pertinent contaminant information current in 

tracking any changes in perchlorate status, because EPA has decided to regulate perchlorate in 

drinking water. EPA has found that perchlorate may have an adverse effect on human health. EPA 

has reversed its October 2008 preliminary determination not to develop an NPDWR for perchlorate 

and now concludes, based on the analysis presented in the final regulatory determination notice, that 

there is a substantial likelihood that perchlorate will occur in public water systems with a frequency 

and at levels of public health concern. Finally, EPA has determined that regulation of perchlorate 

presents a meaningful opportunity to reduce health risk for persons served by public water systems. 

The Safe Drinking Water Act requires EPA to review each National Primary Drinking Water 

Regulation (NPDWR) at least once every six years and revise them, if appropriate. The purpose of 

the review, called the Six-Year Review, is to identify those NPDWRs for which current health 

effects assessments, changes in technology, and/or other factors provide a health or technical basis 

to support a regulatory revision that will maintain or strengthen public health protection. EPA will 

address changes in the science and occurrence at that time. 

Commenter Name: Laurence Scudder 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1581 

EPA Comment ID: 20561 

EPA Comment Code: 6130 

 

Comment: I urge the U.S. Environmental Protection Agency to reverse its preliminary 

determination on setting a regulation for perchlorate in drinking water. It is my understanding that 

the effects of levels of perchlorate in our drinking water have not been fully researched. Until said 

testing has been performed, I believe it is inconclusive to set a standardized acceptable level of 

perchlorate in our drinking water. Most of all because perchlorate affects the thyroid gland almost 

exclusively. This fact targets our children and unborn children as their thyroids are responsible for 

their growth and development not just metabolism as in adults. Thank you for your time and 

strongly consider my plea. Sincerely, Laurence Scudder 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. 

Commenter Name: Samuel A. L. Perry 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1604 

EPA Comment ID: 20563 

EPA Comment Code: 6130 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1009 of 1099

Comment: While I think perchlorate should be regulated, I would support a reduced monitoring 

framework for those water systems that have samples less than half any MCL that eventually gets 

developed. I also understand that monitoring costs may drop significantly as new analytical 

platforms are developed. 

Sincerely, Samuel A. L. Perry, P.E. 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. Specific regulatory requirements for public water systems (including monitoring) will be 

presented for public comment with the proposed NPDWR. 

Commenter Name: James Taft 

Commenter Organization: Association of State Drinking Water Agencies 

EPA Document ID: EPA-HQ-OW-2008-0692-1527 

EPA Comment ID: 20634 

EPA Comment Code: 6130 

 

Comment: November 10, 2008 

Comment Clerk Docket EPA-HQ-OW-2008-0692 Water Docket Environmental Protection Agency 

Mail Code: 2822T 1200 Pennsylvania Ave., NW. Washington, DC 20460 

Dear Sir: 

In response to the notice in the Federal Register of October 10, 2008 (Volume 73, Number 198) the 

Association of State Drinking Water Administrators (ASDWA) is offering comments to the U.S. 

Environmental Protection Agency (EPA) on the Preliminary Regulatory Determination on 

Perchlorate. ASDWA is the professional Association that represents the collective interests of the 

nation's state drinking water programs responsible for implementation of the Federal Safe Drinking 

Water Act. 

EPA’s regulatory development activities are very important to states. Although some states have the 

expertise and resources to conduct their own evaluations of contaminant risks and may set their 

own, more stringent regulatory controls, most states rely on the EPA to determine which 

contaminants should be regulated in drinking water and at what levels. It is critical that these 

determinations are based on sound science and accomplished through a transparent process with 

appropriate input from all interested parties, especially states. This is especially true in the case of 

perchlorate, since this contaminant has garnered extensive public and political interest in the last few 

years. 

ASDWA appreciates the opportunity to provide the perspective of states on the Agency’s 

preliminary determination for perchlorate. States are generally in favor of EPA’s decision not to 

regulate, but there are some states that do favor national regulation of perchlorate, especially those 

who have already set their own standard. The Agency should expect direct comments from some of 

these states. We do have a few recommendations to offer related to the perchlorate decision about 

tools and information that we believe would benefit to all states. These recommendations do not 

include a recommendation to regulate, but they do go beyond the norm. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1010 of 1099

Regardless of EPA’s regulatory decision, states will need to act - Even if EPA does not adopt a 

national regulation of perchlorate, the public will likely demand a response to detections of elevated 

levels of perchlorate - particularly, in light of the notoriety associated with this contaminant. The 

occurrence data may not support regulation of perchlorate, but the data do show that there are a 

significant number of water sources where perchlorate was detected, and at least a few where the 

levels are a public health concern. Because the decision not to regulate was based on a low national 

number of detects at levels of concern and not a lack of health effects, there is still a need for action 

in some cases, even if a national standard is not justified. In states where there are detections of 

perchlorate at levels of concern, drinking water programs need to be able to respond appropriately 

so that public health can be protected. At a minimum, states will need to assist individual water 

systems with the specific actions needed to control perchlorate. Information is needed from EPA on 

risk characterization and risk management as well as treatment options and alternative control 

measures to support state efforts. In some cases, a state may decide that perchlorate is common 

enough in their source waters that they are interested in developing statewide control measures, 

whether it is a formal monitoring program or a state specific MCL. We believe the Agency has data 

and expertise that can help support these actions. 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. EPA will provide further risk characterization and risk management information as part 

of the national primary drinking water standard. 

Commenter Name: Lewis Zediana 

Commenter Organization: Tewksbury Water Department 

EPA Document ID: EPA-HQ-OW-2008-0692-1670 

EPA Comment ID: 20669 

EPA Comment Code: 6130 

 

Comment: Please find attached my comments on this subject. 

Perchlorate should not be dropped from the list. Montioring can be adjusted by allowing waivers 

while taking into consideration the surrounding area and chances of contamination. However more 

protection can be afforded to the populace by expanding the monitoring program to the effluent of 

wastewater plants. Which as by our experience can release Perchlorate passed inot the system.. 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. EPA intends to present specific regulatory requirements for public water systems 

(including monitoring) for public comment with the proposed NPDWR. This action does not 

address waste water discharges. 

Commenter Name: Lyndsey Crum 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1732 

EPA Comment ID: 20679 

EPA Comment Code: 6130 

 

Comment: While I support the EPA’s desire to not promulgate NPDWR for perchlorate for the 

reason above, I am concerned about the health implications this will have for the sensitive 

subpopulations of infants, pregnant women and those likely to become pregnant. Although the 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1011 of 1099

connection between perchlorate and thyroid related health and cognitive defects is not conclusion, 

the EPA presents evidence that suggest such a link could exists. The possibility should be sufficient 

to warrant clearer, quantitative research targeting these populations, particularly in industrial 

communities where perchlorate could enter the public water supply. 

In addition to a targeted study, the agency should consider the costs of not regulated perchlorate 

versus the possible treatment costs associated with thyroid conditions. Regulatory cost saving should 

not outweigh the cost of prevention. 

Although the EPA is not required to promulgate NPDWR for perchlorate, should it conduct 

additional research, in which that research produces a strong health risk concern; EPA should create 

a NPDWR to address regulation needs. The regulation could be enforcing only when the state 

health agency has not already passed a sufficient state public drinking water regulation. 

Lyndsey Crum lcrum10@law.du.edu 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. To do so, EPA used the best available peer-reviewed science and does not think that an 

additional targeted study is necessary at this point. EPA intends to develop a proposed NPDWR, at 

which time EPA will analyze, among other things, quantifiable and nonquantifiable health risk 

reduction benefits as well as costs of a rule, the effects of perchlorate on the general population and 

specific life stages, and other relevant factors with respect to the degree and nature of the risk. See 

42 USC 1412(b)(3)(C). 

Because EPA has decided to regulate perchlorate in drinking water the Safe Drinking Water Act 

requires EPA to review each National Primary Drinking Water Regulation (NPDWR) at least once 

every six years and revise them, if appropriate. The purpose of the review, called the Six-Year 

Review, is to identify those NPDWRs for which current health effects assessments, changes in 

technology, and/or other factors provide a health or technical basis to support a regulatory revision 

that will maintain or strengthen public health protection. EPA will evaluate changes in the science 

and occurrence at that time. 

Commenter Name: Richard Weaver 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1868 

EPA Comment ID: 20752 

EPA Comment Code: 6130 

 

Comment: Management, 

Clean Water Action: 

Please consider offering surveyed citizens more comprehensive information on the perchlorate in 

drinking water. Please also offer them either a pre-written form or guideliness on writing to the EPA 

on this issue. Thank you 

Richard Weaver 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1012 of 1099

Response: EPA has provided comprehensive information through three Federal Register notices 

and has provided instructions on how to provide comments. Furthermore, pursuant to 42 USC 

300(b)(3)(B), EPA intends to publish a document in support of its NPDWR that specifies, to the 

extent practicable-- (i) each population addressed by any estimate of public health effects; (ii) the 

expected risk or central estimate of risk for the specific populations; (iii) each appropriate upperbound or lower-bound estimate of risk; (iv) each significant uncertainty identified in the process of 

the assessment of public health effects and studies that would assist in resolving the uncertainty; and 

(v) peer-reviewed studies known to the Administrator that support, are directly relevant to, or fail to 

support any estimate of public health effects and the methodology used to reconcile inconsistencies 

in the scientific data. 

Commenter Name: Rebecca Downey 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1888 

EPA Comment ID: 20774 

EPA Comment Code: 6130 

 

Comment: I urge you to reconsider any decisions on this important matter until proper analysis of 

all studies, including those that contradict industry studies, have been properly assessed and 

considered. 

Sincerely, 

Rebecca Downey 

Rebecca Downey sent this message via Congress.org, which uses the Capwiz.XC system. 

Congress.org is a free public service of Capitol Advantage and Knowlegis, LLC. You may access 

Congress.org here: http://congress.org 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. This determination was based on analysis of the best available science. 

Commenter Name: Lucy Allen 

Commenter Organization: Pacific Institute 

EPA Document ID: EPA-HQ-OW-2008-0692-1770 

EPA Comment ID: 20927 

EPA Comment Code: 6130 

 

Comment: Without an enforceable federal standard, the Department of Defense, which is a 

primary user of perchlorate in the U.S., will perform remediation efforts according to a patchwork 

of state and agency guidelines. According to the EPA, approximately 90 percent of perchlorate 

produced in the United States is for defense activities and NASA.[FN7: EPA (2007). Perchlorate. 

Environmental Protection Agency, Federal Facilities Restoration and Reuse. Retrieved Oct. 24, 2008 

from http://www.epa.gov/fedfac/documents/perchlorate.htm.] Recognizing perchlorate 

contamination is a defense-related hazardous waste issue with significant potential impact on human 

health, the Department of Defense (DOD) designated perchlorate as an emerging contaminant and 

has taken some action to clean up contamination, mostly in the form of responding to requests 

made by the EPA and states-requests that relied on piecing together statutes, regulations, and the 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1013 of 1099

power of oversight agencies.[FN8: GAO (2007). Department of Defense Activities Related to 

Trichloroethylene, Perchlorate, and Other Emerging Contaminants. Government Accountability 

Office. July, 2007. Retrieved October 24, 2008 from http://www.gao.gov/new.items/d071042t.pdf.] 

While the DOD is responsible by law for remediation of contaminants regulated by the EPA or the 

state, its responsibility for what it classifies as "emerging contaminants" is not clearly defined. 

In 2006, the DOD adopted its own management policy in which they are to comply with state or 

federal standards, whichever is most stringent. According to this policy, in the absence of state or 

federal standards, the DOD will manage its control action using 24 parts per billion (ppb) as the 

level of concern. Because a federal standard has not yet been established, the DOD must use state 

regulations to guide its remediation efforts. But while a handful of states have nonregulatory 

perchlorate-level guidelines, only two states-Massachusetts and California-have set enforceable 

perchlorate drinking- water standards (1 ppb and 6 ppb respectively). Perchlorate contamination and 

its potential adverse health impacts, however, is obviously a multistate issue.[FN9: GAO 2007 finds 

federal and state agencies have found perchlorate in groundwater, surface water, soil, or public 

drinking water systems at almost 400 sites representing over 37 states, in concentrations that ranged 

from 4 parts per billion (ppb) to more than 3.7 million ppb. 

http://www.gao.gov/new.items/d07797t.pdf] Without a federal standard, not only will the DOD 

have to overcome the difficult challenge of performing remediation efforts according to varied 

guidelines, but states that currently lack their own enforceable standards and have known sources of 

perchlorate may be left with remediation efforts based on the DOD’s 24 ppb management standard. 

In the absence of a federal standard, remediation efforts by EPA and state officials of public 

drinking water systems contaminated by perchlorate have been shown to be nonexistent. DOD 

remediation efforts are not alone in their need for guidance from a federal perchlorate standardcleanup of perchlorate in public drinking water systems has been shown to be nonexistent without a 

federal standard. According to research done by the GAO, "EPA and state officials told us they had 

not cleaned up contaminated public drinking water systems, principally because there was no federal 

drinking water standard or specific federal requirement to clean up perchlorate."[FN10: GAO. 

(2007). Perchlorate: EPA Does Not Systematically Track Incidents of Contamination. Retrieved Oct 

27, 2008 from http://www.gao.gov/new.items/d07797t.pdf.] 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20989 

EPA Comment Code: 6130 

 

Comment: DETAILED COMMENTS 

1. EPA has made a preliminary determination not to set a health standard for perchlorate without 

reviewing or considering peer review and public comments on key pieces of evidence which it relies 

upon for its determination. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1014 of 1099

As EPA announced in its preliminary determination on perchlorate, the Agency is planning to issue 

a final determination by December 2008. However, NRDC has learned that the PBPK peer review 

reports of the staff report have only recently been submitted to EPA and were not incorporated into 

EPA's analysis in making its regulatory determination. Furthermore, NRDC has learned that EPA 

has solicited peer review comments on the HRL itself, and to date, is still awaiting those comments. 

EPA should not proceed with any decision on perchlorate until all the peer review reports have been 

submitted to EPA, reviewed by EPA scientific staff and managers, and made available for public 

scrutiny. 

If EPA finalizes its preliminary determination, in the absence of strong state drinking water 

standards for perchlorate, the HRL will provide the only guidance for Superfund cleanup levels and 

health advisories for perchlorate. The importance of the HRL if EPA chooses not to regulate 

perchlorate underscores the importance that it be fully peer reviewed and those comments be made 

available to the public before EPA finalizes its determination. There is no justification for EPA's 

apparent intent to race ahead with a decision not to set a health- standard for perchlorate, and to rely 

upon an inadequate health reference level, prior to receiving, considering, and responding to both 

peer review and public comment. Failing to give these comments sufficient consideration in making 

its final determination would render EPA's final action arbitrary and capricious. 

Response: All the peer review reports have been submitted to EPA, reviewed by EPA, and made 

available for public scrutiny. EPA has considered the results of the peer review reports in reaching 

the determination it announces today to regulate perchlorate in drinking water. See response to 

comment code 6120. 

Commenter Name: Dawn M. Lee 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2117 

EPA Comment ID: 21968 

EPA Comment Code: 6130 

 

Comment: Dawn M. Lee 1219 Severnview Dr. Crownsville, MD 21032 

Water Docket, EPA Mailcode 2822T 1200 Pennsylvania Ave. Washington, DC 20460 

Re: EPA-HQ-OW-2008-0692 

I am writing to express my concerns regarding the issue of perchlorate levels in our drinking water 

in the United States. I feel this chemical should be further studied and monitored in our drinking 

water and water tables, and eliminated as much as possible. For the future of our children and their 

children, please continue to study the effects of perchlorate do not allow this chemical to remain 

uncontrolled in our drinking water. 

Thank you, Dawn M. Lee 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. To do so, EPA used the best available peer-reviewed science. EPA intends to present 

specific regulatory requirements for public water systems (including monitoring) for public comment 

with the proposed NPDWR. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1015 of 1099

Commenter Name: Carrie Manion 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2121 

EPA Comment ID: 21997 

EPA Comment Code: 6130 

 

Comment: 2194 Dairy Farm Road Gambrills, MD 21054 

November 20, 2008 

Environmental Protection Agency Water Docket 1200 Pennsylvania Ave. Washington, DC 

RE: EPA-HQ-OW-2008-0692 

Dear Sirs/Madam: 

A recent online review of information about perchlorate proved very interesting. It seems that 

several states are imposing limitations on the presence of perchlorate in water; however the 

recommended "safe" levels are inconsistent. 

I feel that in order for the public to be protected by the potential risks associated with ingesting 

perchlorate, the EPA should conduct further, in depth studies into the actual ramifications of this 

chemical. 

Instituting a drinking water regulation cannot be done until accurate, authoritative research into the 

health impacts is conducted. 

I look forward to seeing the results of such tests in a timely manner. 

Carrie Manion Resident of Anne Arundel County, Maryland 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. To do so, EPA used the best available peer-reviewed science. EPA intends to conduct 

further analyses, pursuant to the requirements of 42 USC 300g-1(3)(C)(i), in promulgating the 

NPDWR with a maximum contaminant level. 

Commenter Name: Andy Burgess 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2217 

EPA Comment ID: 22417 

EPA Comment Code: 6130 

 

Comment: All Americans deserve healthy and clean drinking water. The EPA should not finalize 

this decision until the scientific review is complete and should make decisions that are consistent 

with the agency's own scientists. Contrary to your claims, protecting the health of young children is 

indeed a "meaningful opportunity for health risk reduction." 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1016 of 1099

Response: All the peer review reports have been submitted to EPA, reviewed by EPA, and made 

available for public scrutiny. EPA has considered the results of the peer review reports in reaching 

the determination it announces today to regulate perchlorate in drinking water. See response to 

comment code 6120. 

Commenter Name: Rose Lernberg 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2246 

EPA Comment ID: 22429 

EPA Comment Code: 6130 

 

Comment: Please do not finalize this decision until the scientific review is complete. Please make 

decisions that are consistent with the agency's own scientists. 

Sincerely, Rose Lernberg 831 Balra Drive E1 Cerrito, CA 94530 

Response: All the peer review reports have been submitted to EPA, reviewed by EPA, and made 

available for public scrutiny. EPA has considered the results of the peer review reports in reaching 

the determination it announces today to regulate perchlorate in drinking water. See response to 

comment code 6120. 

Commenter Name: Susanna Sayre 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2310 

EPA Comment ID: 24991 

EPA Comment Code: 6130 

 

Comment: Water Docket Environmental Protection Agency Mailcode 2822T,1200 Pennsylvania 

Avenue Washington, DC 20460 

ATTN: Docket ID No. EPA-HQ-OW-2008-0692 

To whom it may concern: 

Perchlorate contamination in drinking water is a nationwide problem. As noted recently by the 

EPA's own Scientific Advisory Board, perchlorate's widespread occurrence in drinking water and its 

well-documented toxicity to humans make it vital to have the best scientific evidence available in 

making a determination as to whether or not perchlorate levels should be regulated. Given its 

potential for posing significant risks to human health, I urge the EPA to delay final action on its 

decision not to set a federal drinking-water standard for perchlorate. I support a national primary 

drinking water regulation governing perchlorate levels to protect public health. 

Yours sincerely, Susanna Sayre 19005 Bloomfield Rd. Olney, MD 20832 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. 

Commenter Name: Michael Sayre 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1017 of 1099

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2327 

EPA Comment ID: 25009 

EPA Comment Code: 6130 

 

Comment: November 10, 2008 Water Docket Environmental Protection Agency Mailcode 2822T, 

1200 Pennsylvania Avenue Washington, DC 20460 

ATTN: Docket ID No. EPA-HQ-OW-2008-0692 

To whom it may concern: 

Perchlorate contamination in drinking water is a nationwide problem. As noted recently by the 

EPA's own Scientific Advisory Board, perchlorate's widespread occurrence in drinking water and its 

well-documented toxicity to humans make it vital to have the best scientific evidence available in 

making a determination as to whether or not perchlorate levels should be regulated. Given its 

potential for posing significant risks to human health, I urge the EPA to delay final action on its 

decision not to set a federal drinking-water standard for perchlorate. I support a national primary 

drinking water regulation governing perchlorate levels to protect public health. 

Yours sincerely, Michael Sayre 19005 Bloomfield Rd. Olney, MD 20832 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. 

Commenter Name: James D. Taft 

Commenter Organization: Association of State Drinking Water Administrators 

EPA Document ID: EPA-HQ-OW-2009-0297-0525 

EPA Comment ID: 28496 

EPA Comment Code: 6130 

 

Comment: Atttached are the comments of the Association of State Drinking Water Administrators 

on the request for additional comments on the regulation of perchlorate (FR Vol. 74, No. 159). 

Additional comments are being submitted directly by states. 

Attachment 

 September 24, 2009 Comment Clerk Docket EPA-HQ-OW-2009-0297 Water Docket 

Environmental Protection Agency Mail Code: 2822T 1200 Pennsylvania Ave., NW. Washington, 

DC 20460 

Dear Sir: 

In response to the notice in the Federal Register of August 19, 2009 (Volume 74, Number 159) the 

Association of State Drinking Water Administrators (ASDWA) is offering comments to the U.S. 

Environmental Protection Agency (EPA) on the Perchlorate Supplemental Request for Comments. 

ASDWA is the professional Association that represents the collective interests of the nation's state 

drinking water programs responsible for implementation of the Federal Safe Drinking Water Act. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1018 of 1099

EPA's regulatory development activities are very important to states. Although some states have the 

expertise and resources to conduct their own evaluations of contaminant risks and may set their 

own, more stringent regulatory controls, most states rely on the EPA to determine which 

contaminants should be regulated in drinking water and at what levels. It is critical that these 

determinations be based on sound science and accomplished through a transparent process with 

appropriate input from all interested parties, especially states. This is particularly true in the case of 

perchlorate, since this contaminant has garnered extensive public and political interest in the past 

few years. We appreciate that EPA is sharing its assessment of health risk and occurrence data and 

requesting additional comment as important regulatory decisions are considered. 

As we noted in our comments on EPA's preliminary decision on perchlorate regulation in October 

2008, states were generally in favor of EPA's preliminary decision not to regulate, but there are some 

states that do favor national regulation of perchlorate, especially those who have already set their 

own standard. In that response, we did recommend some tools and information that we believed 

would benefit all states. Our comments today will address some of the questions in the Agency's 

August 19th request for comments, but also reiterate some of the recommendations in our previous 

letter, where appropriate. 

Response: Please see the response to comment code 6110. 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 28748 

EPA Comment Code: 6130 

 

Comment: In summary, the NDEP believes the EPA should develop a national primary drinking 

water standard for perchlorate using updated, appropriate, and complete data sets; defensible 

analysis; and scientific approaches. The States and general public place a tremendous amount of 

trust in the EPA to make credible decisions. Consequently, we trust the EPA will thoughtfully 

consider our comments and those submitted by other entities during its current evaluation. Much 

more significant public health benefit is achievable and at a much lower cost by targeting iodinedeficient individuals through existing public health programs and correcting the iodine deficiencies 

through adjusted diets, use of supplements, and implementation of educational programs. These 

concepts are not new, yet they have not been addressed in a meaningful way. Congress is capable of 

funding such programs and should be requested to do so in the near term. 

Sincerely, Tom Porta, Deputy Administrator Nevada Division of Environmental Protection 

Tp/tjc cc Jennifer Carr, P.E., CEM, Chief, Bureau of Safe Drinking Water, Nevada Division of 

Environmental Protection, 901 S. Stewart Street, Suite 4001, Carson City, NV 89701-5249 Darrel 

Osterhoudt, Regulatory Affairs Manager, Association of State Drinking Water Administrators, 1401 

Wilson Blvd., Suite 1225, Arlington, VA 22209 Kay Brothers, Deputy General Manager, SNWA 

Engineering/Ops, Southern Nevada Water Authority, 100 City Parkway, Suite 700, Las Vegas, NV 

89106 Dr. Mic Stewart, Manager, Water Quality Section, Metropolitan Water District of Southern 

California, 700 North Alameda Street, Los Angeles, CA 90012 Marie Pearthree, Assistant General 

Manager, Central Arizona Water Conservation District, PO Box 43020, Phoenix, AZ 85080-3020 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1019 of 1099

Brenda Pohlmann, Environmental Programs Manager, City of Henderson, PO Box 95050, 

Henderson, NV 89009 Susan Crowley, Tronox, LLC, PO Box 55, Henderson, NV 89009 Jeff 

Gibson, AMPAC, 3883Howard Hughes Parkway, Suite 70, Las Vegas, Nevada 89109 

Response: Please see the response to comment ID 28857 under comment code 6110. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28795 

EPA Comment Code: 6130 

 

Comment: However, even when basing its decision upon this unacceptably high RfD, EPA's 

preliminary determination not to regulate perchlorate would still expose hundreds of thousands of 

children and infants to unsafe levels of perchlorate. 

Response: EPA has determined to regulate perchlorate in drinking water. See response to comment 

code 6120. For further information about the RfD for perchlorate, please see the response to 

comment ID 28927 under comment code 2110. 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1020 of 1099

EPA Comment Code: 6140 Additional new literature and information for EPA 

to consider when making a regulatory determination 

Individual Comments 

Commenter Name: Bill Connick 

Commenter Organization: University of Cincinnati 

EPA Document ID: EPA-HQ-OW-2009-0297-0190 

EPA Comment ID: 28387 

EPA Comment Code: 6140 

 

Comment: Dear Sir, 

We have developed a new method for detection of perchlorate in aqueous solution with remarkably 

high selectivity. The method is likely to be low- cost relative to exisiting approaches (e.g., those 

described at http://www.cluin.org/contaminantfocus/default.focus/sec/perchlorate/cat/Overview/) and suitable for field 

work. We are preparing a manuscript for submission to the Journal of the American Chemical 

Society describing the discovery. I expect the document will be submitted within 10 days. 

The science described in that account is covered by a provisional patent. We have recently made 

some significant improvements which will greatly increase the sensitivity. If this sounds relevant, 

please feel free to contact me. 

Professor Bill Connick University of Cincinnati (513)-556-0148 bill.connick@uc.edu 

Regards, Bill 

Response: EPA cannot evaluate methods that have not been peer reviewed. However, EPA will 

evaluate the best available, peer reviewed literature as the NPDWR is developed. 

Commenter Name: Richard Nieuwenhuis 

Commenter Organization: New Jersey Farm Bureau (NJFB) 

EPA Document ID: EPA-HQ-OW-2009-0297-0665 

EPA Comment ID: 28533 

EPA Comment Code: 6140 

 

Comment: October 8, 2009 

Water Docket Environmental Protection Agency Mailcode: 2822T 1200 Pennsylvania Avenue 

Washington, DC 20460 

RE: Perchlorate Supplemental Request for Comments (Docket ID No. EPA-HQ- OW-2009-0297) 

Dear Sir/Madam: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1021 of 1099

The New Jersey Farm Bureau (NJFB) is a 13,000 member organization which represents New Jersey 

agricultural producers and enterprises at all levels of government. We thank the Environmental 

Protection Agency (EPA) for the opportunity to provide comments on the above referenced docket 

regarding alternative approaches to the interpretation of scientific data relevant to establishment of a 

national primary drinking water regulation for perchlorate. 

We believe that the approaches EPA described in the August 19, 2009 Federal Register deviate from 

long-established methods by which EPA has analyzed scientific and technical data. We are 

concerned that development of an overly conservative standard for perchlorate, that is not based on 

comprehensive, peer- reviewed science and an appropriate risk-based assessment could 

unintentionally lead to unjustified food scares associated with a wide variety of agricultural 

commodities. Food scares of this nature could deter people away from consuming foods which the 

Food and Drug Administration (FDA) encourages people to eat more of due to their nutritional 

benefits and which the FDA has deemed critical to the health and development of children. 

Furthermore, we are concerned about the economic impacts associated with such food scares. 

Response: SDWA requires the consideration of sensitive subpopulations in developing NPDWRs. 

EPA exposure assessment policy has evolved to provide tools and policies consistent with the 

concern for all life stages. See responses to comments IDs 28813 and 28677 under comment code 

6140. 

Commenter Name: Stephen Haterius 

Commenter Organization: National Association of State Departments of Agriculture (NASDA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0664 

EPA Comment ID: 28548 

EPA Comment Code: 6140 

 

Comment: We remain very concerned that the approaches EPA outlined in the August 19 Federal 

Register will significantly-and unnecessarily-impact American agricultural production and foreign 

trade. Because perchlorate is naturally occurring at low levels in a number of agricultural products, it 

is imperative that EPA's regulatory determination be based upon a sound scientific approach that 

protects public health without unnecessarily creating concerns about the safety of agricultural 

products that are vital to a healthy diet. This is particularly important in light of the fact that the risks 

associated with perchlorate can be easily avoided by the consumption of sufficient iodine-rich foods 

or iodine supplements by a specific subset of the population. 

As we detailed in previous comments, an overly conservative perchlorate standard that is not based 

on sound, peer-reviewed science and an appropriate risk-based assessment could unintentionally 

lead to unjustified food scares on a wide variety of fresh fruits, vegetables, and dairy products. Even 

though EPA's current action is intended only to explore alternative approaches to analyzing data, the 

additional alternatives under consideration could result in health reference levels which are much 

lower than the level identified in the October 2008 notice. NASDA is concerned that this kind of 

standard would likely lead to inaccurate consumer perceptions and confusion about perchlorate in 

agricultural products. The ramifications of this kind of food scare would have devastating impacts 

on agricultural producers and rural communities. For example, a study by Arizona State University 

indicates that a prolonged food scare involving winter lettuce could result in a negative economic 

impact of over $5 billion. 
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Moreover, EPA's actions could have significant impacts on American producers' access to foreign 

markets. The agricultural products impacted by this issue represent nearly $70 billion in export 

opportunities. Because other countries frequently cite food safety concerns as justifications to 

erecting trade barriers to American agricultural products, an overly conservative perchlorate standard 

that is not based on sound, peer-reviewed science and an appropriate riskbased assessment would 

likely lead to the imposition of unfair and economically devastating trade restrictions by America's 

trading partners. 

Response: See responses to comments IDs 28813 and 28677 under comment code 6140. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0653 

EPA Comment ID: 28559 

EPA Comment Code: 6140 

 

Comment: Further conservatism (i.e. more stringent assumptions) concerning hazard or exposure 

beyond central tendencies in the existing data sets is not justified. To follow a precautionary 

principal in setting further restrictions in this case is both arbitrary and capricious. Further, without a 

clear basis for protecting public health, the Agency will cause public and private water providers to 

expend energy to remove perchlorate from water supplies that already protect their consumers. The 

Agency has failed to estimate the carbon emissions and cost that this unnecessary removal, probably 

through dedicated reverse osmosis systems, will cost the American public in higher water rates and 

carbon emissions. The Agency has provided no data on the feasibility of removing perchlorate 

below the preliminary guidance level. In doing so, costs must be estimated for both the construction 

capital costs and based on energy expenditures which are an ongoing annual cost rather than a onetime capital cost. Such ongoing costs must be considered for the life of the project. 

Response: See response to comment ID 28813 under comment code 6140. 

Commenter Name: Sonia Salas 

Commenter Organization: Western Growers Association on behalf of several California 

agriculture groups 

EPA Document ID: EPA-HQ-OW-2009-0297-0652 

EPA Comment ID: 28677 

EPA Comment Code: 6140 

 

Comment: We are further concerned that the food scares which will follow from setting a 

regulatory threshold below the existing natural background level of perchlorate in the environment 

will significantly disadvantage agricultural exports. Agricultural commodities make up a significant 

portion of all U.S. food exports. Given the long history of our Asian trading partners taking 

retaliatory actions for what they deem to be U.S. protectionism -- we are particularly concerned in 

light of the Obama Administration's recent announcement to impose tariffs on Chinese tire 

manufacturers -- a regulatory determination which does not take into consideration the presence of 

naturally occurring perchlorate will provide an unfortunate opportunity for the Chinese government 

to make good on their threats to punish U.S. agricultural exports. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Response: EPA is aware of the need to communicate clearly the implications of the NPDWR that 

is developed. The NPDWR as currently envisioned assumes that no change will be required to the 

food supply. Adjustment to perchlorate exposure will be made in the drinking water supply, 

assuming that the food supply remains in its current state with regard to perchlorate. 

Commenter Name: Robert Callahan 

Commenter Organization: California Chamber of Commerce (CalChamber) 

EPA Document ID: EPA-HQ-OW-2009-0297-0666 

EPA Comment ID: 28693 

EPA Comment Code: 6140 

 

Comment: Please see the attached comment letter regarding the perchlorate supplemental request 

for comments. Thank you. 

Robert Callahan California Chamber of Commerce 

 October 8, 2009 

Ms. Lisa P. Jackson Administrator Environmental Protection Agency 1200 Pennsylvania Avenue, 

NW Washington, DC 20460 

SUBJECT: EPA-HQ-OW-2009-0297, "Drinking Water: Perchlorate - Supplemental Request for 

Comments" 

Dear Ms. Jackson: 

The California Chamber of Commerce (CalChamber) wishes to express our concern with the federal 

Environmental Protection Agency's (EPA) interpretation of the scientific data relevant to a 

regulatory determination for perchlorate in drinking water. While it is imperative to set public health 

standards, especially where a specific threat exists, there is no rationale for establishing lower 

standards or for rushing to a regulatory decision unsupported by scientific information. 

Perchlorate is found naturally throughout the water environment in the 0.5 to 15 parts per billion 

range. The United States Geological Survey and other researchers have also measured perchlorate in 

rain, geologic formations, and rivers and aquifers throughout the United States. Five decades of 

scientific investigation, including a landmark National Academy of Sciences review, result in a clear 

and consistent conclusion: low levels of perchlorate are not dangerous to public health. 

We strongly believe that an unnecessarily lower standard would limit the flexibility of the water 

supply system. Curbs on water supplies, especially during a water emergency, would impact local 

economies and job markets, as plans for new housing areas and business centers are postponed or 

cancelled due to lack of available water. Current residential areas and businesses could also be forced 

to endure unnecessary water shortages, water rationing, rate hikes and other consequences. 

In light of this, it seems clear that the alternatives proposed by EPA are not justifiable considering 

the significant economic costs that would be incurred without corresponding benefits to public 

health. Please keep these considerations in mind as the EPA determines additional approaches to 

interpreting perchlorate level data. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1024 of 1099

Sincerely, Robert Callahan Policy Advocate RC:fg 

Response: See response to comment ID 28813 under comment code 6140. As explained elsewhere 

in this response to comments document (comment ID 28863 under comment code 2110), EPA 

believes that the RfD derived by the NRC is the best health assessment available for assessing risk to 

perchlorate. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2009-0297-0647 

EPA Comment ID: 28719 

EPA Comment Code: 6140 

 

Comment: Appendix 1 

A first step towards a possible link perchlorate-organohalogens-TH 

It has been shown that chlorine-based disinfectants such as those found in drinking water oxidize to 

perchlorate as a disinfection by-product (DBP). This is, for example, why Massachusetts doubled its 

MCL from 1 to 2 ppb, because otherwise health-protecting chlorination of drinking water and 

swimming pools with bleach would have to be curtailed. Is this oxidation of perchlorate from bleach 

(hypochlorite and hypochlorous acid) and other chlorine derivates significant in comparison with 

daily intake of perchlorate? 

According to the Blount study (based on the NHANES survey data) the average urinary perchlorate 

level in the population is 2.84ug/l which is roughly equivalent to an oral dose of 0.04 ug/kg-day. 

This corresponds with drinking water of 1.4 ppb. Massachusetts' MCL was based on data that 

showed that about 0.5 ppb perchlorate originated from bleach alone[FN16: -Massachusetts 

Department of Environmental Protection. Perchlorate: Draft Toxicological Profile and Health 

Assessment. 2004. - Occurrence of Perchlorate in Sodium Hypochlorite, Journal American Water 

Works Association (AWWA), Nov. 2008.]. Therefore about 1/3 of the average daily intake of 

perchlorate would be due to bleach oxidation alone, which is substantial and which shows that 

chlorine could be a significant source of low level perchlorate. 

Bleach is used ubiquitously, as for example in water purification stations, paper mills, drinking water 

and for many other applications. Other potential sources of perchlorate as a DBP are other chlorine 

derivates such as chlorine gas and chloramine. On the other hand other DBPs originate from the 

reaction of chlorine based disinfectants with organic matter (waste) to form organochlorides[FN17: 

Gary A. Boorman, Vicki Dellarco, June K. Dunnick, Robert E. Chapin, Sid Hunter, Fred 

Hauchman, Hank Gardner, Mike Cox, and Robert C. Sills. Drinking Water Disinfection Byproducts: 

Review and Approach to Toxicity Evaluation. Environmental Health Perspectives Supplements, 

February 199, Volume 107, Number S1.]. What could be one of the possible pathways that link 

perchlorate to organochlorides such as PCBs via chlorine? 

According to EPA the building block for organochlorides is chlorophenol, and chlorophenols are 

produced from the organic matter found in used water when it reacts with chlorinated 

disinfectants[FN18: Environmental Protection Agency, EPA/600/P-03/002F).An Inventory of 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Sources and Environmental Releases of Dioxin- Like Compounds in the United States for the Years 

1987, 1995 and 2000. Federal Register: December 1, 2006 (Volume 71, Number 231)] Page 69564-

69565] Occurrence of Perchlorate in Sodium Hypochlorite, Journal American Water Works 

Association(AWWA), Nov. 2008] (phenol is benzene with a hydroxyl group and PCBs are basically 

2 chlorinated benzene rings). Those DBPs are found back in the drinking water leaving the water 

purification plants. 

Therefore, this is one example of the possible link between very low levels of perchlorate and TH 

affecting substances: chlorine based disinfectants such as bleach, Cl2 and chloramines evolve to 

perchlorate in one way and to phenols, PCBS and other organochlorides including dioxin-like 

compounds in another way. [Chloramines, besides being an added disinfectant, can also be formed 

as a reaction product of bleach with ammonia, itself amply present in used water (see ref. 15 )]. 

Response: EPA is aware of the link between perchlorate and hypochlorite/hypochlorous acid. This 

issue, and those related to other possible transformation products, will be considered in the context 

of NPDWR development. 

Commenter Name: Jennifer Sass 

Commenter Organization: Natural Resources Defense Council (NRDC) 

EPA Document ID: EPA-HQ-OW-2009-0297-0412 

EPA Comment ID: 28813 

EPA Comment Code: 6140 

 

Comment: A Final MCL Below 1 ppb is Both Technologically and Economically Feasible 

U.S. EPA's Method 314 approved ion chromatography detection protocol, for example, routinely 

detects perchlorate pollution at levels of 0.2ppb and the State of Massachusetts has established a 

'reportable concentrations level for perchlorate of 2 ppb.[FN66: Thorne, Philip G. Field Screening 

Method for Perchlorate in Water and Soil, ERDC/CRREL Technical Report 04-8, 36 pp, Apr 

2004.],[FN67: "Final Changes to the Massachusetts Contingency Plan -310 CMR 40.0000," 

downloaded from http://www.mass.gov/dep/cleanup/laws/perchlorate-310CMR40-07282006.pdf, 

November 2 2006.] Ion exchange technology is able to treat perchlorate contamination to levels 

considerably below 1 ppb. Treatment systems operating on perchlorate- impacted wells owned by 

Aquarion Water Company in Massachusetts, for example, treat wells to below 1 ppb.[FN68: "US 

Filter Recovery Services," downloaded from www.usfilter.com, November 2 2006.] 

Economically, the cost of complying with a perchlorate MCL less than 1 ppb for the City of Rialto - 

one of the most impacted water systems in California - for example will be zero after cleanup costs 

are recovered from identified responsible parties. A complete economic feasibility study should also 

include an analysis of the costs associated with healthcare and lost work resulting from illnesses 

associated with perchlorate contaminated water. 

Response: EPA agrees that analytical methods and treatment techniques are available to address 

increasingly smaller concentrations of perchlorate. As the NPDWR is developed, economic 

feasibility will be evaluated in support of identifying an MCL. 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 
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EPA Document ID: EPA-HQ-OW-2009-0297-0650 

EPA Comment ID: 28824 

EPA Comment Code: 6140 

 

Comment: Document ID No. EPA-HQ-OW-2009-0297 

Additional NDEP Comments to "Drinking Water: Perchlorate Supplemental Request for 

Comments" noticed by the USEPA in the August 19, 2009 Federal Register. 

These additional comments focus on: (1) the lack of a demonstrative environmental or public health 

benefit being realized when an MCL is applied to existing well-managed remediation sysytems in the 

Las Vegas Valley if a low standard is developed that does not consider all of the recent 

epidemiological literature; and (2) analytical challanges associated with accurately measuring 

perchlorate in water with elevated EC. 

 October 8, 2009 

U.S. Environmental Protection Agency Mailcode 2822T 1200 Pennsylvania Ave., NW. Washington, 

DC 20460 

Subject: Docket ID No. EPA-HQ-OW-0297 

Reference: Drinking Water: Perchlorate Supplemental Request for Comments (Federal Register / 

Vol. 74, No. 159 / Wednesday, August 19, 2009 / Notices 

The Nevada Division of Environmental Protection (NDEP) submits these additional comments in 

response to the referenced "Supplemental Request for Comments" noticed by the U.S. 

Environmental Protection Agency (EPA) in the August 19, 2009 Federal Register; Docket ID No. 

EPA-HQ-OW-2009-0297. These comments are submitted in addition to comments previously 

provided by the NDEP dated September 16, 2009. The comments are provided within the extended 

comment period and are designed to assist the EPA in their efforts in evaluating whether there is a 

meaningful opportunity for human health risk reduction of perchlorate to persons served by public 

water systems through promulgating a national primary drinking water rule for perchlorate. 

The NDEP understands that in order to regulate a contaminant in drinking water [i.e., develop a 

maximum contaminant level (MCL)], EPA must determine that the contaminant meets the 

following three criteria: 

1) The contaminant may have an adverse effect on human health; 

2) The contaminant is known to occur (or there is a substantial likelihood that the contaminant will 

occur) in public water systems, with a frequency and at levels of public health concern; and 

3) Regulation of such a contaminant presents a meaningful opportunity for health risk reduction for 

persons served by public water systems. 

These additional comments focus on two primary elements: 
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* The lack of a demonstrative environmental or public health benefit being realized when a drinking 

water standard (maximum contaminant level [MCL)) is applied to permitted waste water discharges 

from existing well-managed remediation systems in the Las Vegas Valley if a low standard is 

developed that does not consider all of the recent epidemiological literature; and 

* analytical challenges associated with accurately measuring perchlorate in water with elevated 

electrical conductivity (EC). 

Lack of Benefit Realized and Difficulties Applying a Very low MCL: 

MCLs are used by States, Territory's, and the Federal government to determine when an action may 

be required (action level) as well as when remediation may cease (remediation standard). 

Additionally, many regulatory agencies (including the NDEP) use MCLs, when they are available, for 

water quality criteria applicable to water quality permits. Two principal permit programs overseen by 

the NDEP in the State of Nevada are the National Primary Discharge Elimination System (NPDES) 

program and the Underground Injection Control (UIC) program. Permits issued by these programs 

not only are used to regulate the water quality of waste water discharges from various industries and 

governmental entities; these permits are also used to regulate the water quality of discharges from 

environmental remediation systems. Use of MCLs to set discharge limitations in these permitting 

programs where drinking water is the designated beneficial use of the receiving water is typical 

throughout the US. 

Two significant environmental remediation projects are actively remediating perchlorate-impacted 

groundwater within the Las Vegas Valley (NDEP 2009). Tronox (formerly Kerr-McGee) operates a 

Fluidized Bed Reactor (FBR) that treats approximately 1,000 gallons per minute (gpm) with a typical 

influent concentration of approximately 500 milligrams per liter (mg/L) perchlorate. AMPAC 

operates an In-situ Bioremediation (ISB) system that treats approximately 200 to 300 gallons per 

minute with a typical influent concentration of 20 to 30 mg/L perchlorate. Both treatment systems 

additionally treat (destroy) large amounts of chlorate and nitrate due to the advantageous use of 

bioremediation. Bioremediation of perchlorate is nonselective; hence significant environmental and 

human health benefits are realized through use of these technologies (FBR and ISB) to treat large 

volumes of water impacted with elevated concentrations of perchlorate. 

Both the Tronox and AMPAC bioremediation systems are designed to operate with more electron 

donor provided than is necessary to destroy all of the nitrate, chlorate, and perchlorate present 

within the influent water. These treatment systems are designed this way because it would be 

incredibly difficult to precisely meter an amount only necessary for the required mass destruction 

given that small changes in influent concentrations (of perchlorate, chlorate, and nitrate) occur. As 

such, the treatment systems are designed and the actual operations are managed in ways that the 

treated water typically exhibits no detectable concentration of perchlorate. Stated another way, there 

is no advantage to operate these remediation systems in a manner that conserves electron donor but 

puts the permittee (Tronox and AMPAC) at risk of a NPDES or UIC permit violation. 

The practical challenge is not one of treatment system design and operation, but rather of 

monitoring. Significant challenges exist in identifying and quantifying perchlorate in the Tronox 

NPDES permitted discharge and AMPAC UIC permitted discharge at values typically less than 

approximately 10 ug/L and 6 ug/L, respectively. Additionally, the actual environmental benefit that 

could be perceived to be present if the permit discharge values were lowered significantly is in the 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

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range of less than 1/2 pound per day mass loading to the receiving waters. The down side associated 

with placing a significantly lower standard on the referenced permits is that the two treatment 

systems would be precariously positioned for permit exceedance. It makes little sense to the NDEP 

to effectively establish discharge permit conditions that increase potential for noncompliance with 

two very important and very successful perchlorate treatment systems and at the same time provide 

no measureable environmental benefit or public health risk reduction. 

Analytical Challenges: 

Most perchlorate remediation that occurs throughout the United States involves significantly lower 

concentrations of perchlorate particularly when higher amounts of water are treated. Additionally, 

the baseline water quality applicable to those remediation projects is much different on those 

projects than for projects within the and Mojave Desert region of the southwestern United States 

including projects within the Las Vegas Valley. Total dissolved solids (TDS) concentrations of 

shallow groundwater within the Las Vegas Valley typically exceed 1,000 mg/L and often can be 

measured between 3,000 and 10,000 mg/L. Electrical conductivity (EC) measurements (specific 

conductance) often are used in lieu of TDS measurements to permit rapid, cost-effective analysis of 

water quality when monitoring ground water, surface water, and NPDES and UIC permitted 

discharges. Although EC and TDS measurements are not identical, the two are well correlated. 

It is important to note that the treated water discharged from the Tronox FBR remediation system 

typically measures in the range of 10,000 mg/L. Similarly, it is helpful to know that the donoramended water injected via a UIC permit by AMPAC to allow for ISB of perchlorate typically 

measures in the range of 3,000 to 4,500 mg/L TDS. The analytical method routinely used to 

quantify perchlorate in water is EPA Method 314.0 or 314.1. Both of these Ion Chromatography 

(IC) based methods do not provide reliable results when the water samples being tested are in the 

range (or exceed) approximately 7,000 us/cm (reference Table 1 and the related analytical summaries 

in Attachment A). Additionally, these methods are presumptive methods in that they do not provide 

a definitive determination that the detected analyte is perchlorate as can be seen in Table 1. The 

influent water to the above referenced treatment systems additionally contain a number of other 

analytes that can co-elute or otherwise compromise the detection and quantification of perchlorate. 

It is for these reasons that: 

* Other methods have been developed for use particularly with saline samples; 

* Mass spectrometry (MS) is used as the detector in more robust analytical methods that are 

preferred by many knowledgeable chemists and other professionals working with perchlorate 

identification, quantification, and remediation as these advanced methods provide superior results; 

and 

* It is very difficult to identify and quantitate perchlorate to very low concentrations (generally less 

than between 6 and 10 ug/L) in water that exhibits elevated TDS and/or other confounding 

analytes. 

In summary, the NDEP recommends EPA conduct a thoughtful review of all of the data and 

literature at this time. EPA should consider the side-effects and unnecessary costs external to the 

Safe Drinking Water Program (SDWA) that are involved with using the proposed methodologies to 

set an MCL at a level that is not readily attainable nationally using available analytical methods and 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1029 of 1099

readily available equipment. Alternatively, EPA should demonstrate additional measureable 

environmental or public health benefit that would justify these additional external costs. The 

selection of appropriate analytical methods for use in different applications (drinking water, waste 

water, treated water from remediation systems) is crucial to enable the collection of useable data. 

Additionally, the application, of a scientifically based defensible regulatory standard (Health 

Advisory, MCL, or other standard) throughout the perchlorate remediation and monitoring process 

is a critical component to successful remediation and monitoring of perchlorate in environmental 

media. 

We trust the EPA will thoughtfully consider our comments and those submitted by other entities 

during its current evaluation. 

Sincerely, Tom Porta, Deputy Administrator Nevada Division of Environmental Protection 

Tp/tjc cc Jennifer Carr, P.E., CEM, Chief, Bureau of Safe Drinking Water, Nevada Division of 

Environmental Protection, 901 S. Stewart Street, Suite 4001, Carson City, NV 89701-5249 Darrel 

Osterhoudt, Regulatory Affairs Manager, Association of State Drinking Water Administrators, 1401 

Wilson Blvd., Suite 1225, Arlington, VA 22209 Kay Brothers, Deputy General Manager, SNWA 

Engineering/Ops, Southern Nevada Water Authority, 100 City Parkway, Suite 700, Las Vegas, NV 

89106 Dr. Mic Stewart, Manager, Water Quality Section, Metropolitan Water District of Southern 

California, 700 North Alameda Street, Los Angeles, CA 90012 Marie Pearthree, Assistant General 

Manager, Central Arizona Water Conservation District, PO Box 43020, Phoenix, AZ 85080-3020 

Brenda Pohlmann, Environmental Programs Manager, City of Henderson, PO Box 95050, 

Henderson, NV 89009 Susan Crowley, Tronox, LLC, PO Box 55, Henderson, NV 89009 Jeff 

Gibson, AMPAC, 3883Howard Hughes Parkway, Suite 70, Las Vegas, Nevada 89109 

 Table 1: Comparison of Analytical Methods used for Measuring Perchlorate in Aqueous Samples 

[see PDF docket ID EPA-HQ-OW-2009-0297-0650] 

Attachment A [see PDF Docket ID EPA-HQ-OW-2009-0297-0650] 

References: 

Federal Register, 2008, Final Update IV, SW-846, Volume 73, Number 2; (wais.access.gpo.gov ) 

[DOC ID:fr03ja08-36] 

Interstate Technical Regulatory Council, 2005, Perchlorate: Overview of Issues, Status, and 

Remedial Actions, ITRC Document, September 2005 

Magnuson, Matthew L., Urbansky, Edward T., and Kelty, Catherine A., 2000, Determination of 

Perchlorate at Trace Levels in Drinking Water by Jon-Pair Extraction with Electrospray Ionization 

Mass Spectrometry, Analytical Chemistry, Vol. 72 No. 1, January 1, 2000 

Nevada Division of Environmental Protection (NDEP), 2009, Response to Supplemental Request 

for Comments, noticed by the US Environmental Protection Agency in the August 19, 2009 Federal 

Register; Docket ID No. EPA-HQ- OW-2009-0297 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1030 of 1099

Sellers, Kathleen, Aslop, William, Clough, Stephen, Hoyt, Marilyn, Pugh, Barbara, Robb, Joseph and 

Weeks, Katherine, 2007, Perchlorate: Environmental Problems and Solutions; CRC Press, Boca 

Raton, FL. Chapter 3, pgs. 43 to 63 

Shen-yi Yang, 2007, SW 846 Methods for The Analysis of Perchlorate in Various Environmental 

Media, Power Point Presentation, USEPA Office of Solid Waste. 

USEPA, 1999, Method 314.0, Determination of Perchlorate in Drinking Water Using Ion 

Chromatography, Rev. 1.0. Available at www.epa.gov/safewater/methods/source.html 

USEPA, 2005a: Method 314.1, Determination of Perchlorate in Drinking Water Using Nine 

Column Concentration/Matrix Elimination Ion Chromatography with Suppressed Conductivity 

Detection, Rev. 1.0, Available at www.epa.gov/safewater/methods/source.html. EPA Document 

No. EPA 815-R-05-009. 

USEPA, 2005b, Method 331.0, Determination of Perchlorate in Drinking Water by Liquid 

chromatography Electrospray Ionization Mass Spectrometry, Rec. 1.0. Available at 

www.epa.gov/safewater/methods/source.html. EPA Document No. 815- R-05-007. 

USEPA, 2005c, Method 332.0, Determination of Perchlorate in Drinking Water by Ion 

Chromatography with Suppressed Conductivity and Electrospray Ionization Mass Spectrometry. 

Available at www.epa.gov/safewater/methods/souree.html. EPA Document No. EPA/600/R05/049. 

USEPA, 2007, Method 6850, Perchlorate in Water, Soil and Solid Wastes Using High Performance 

Liquid Chromatography/Electrospray Ionization/Mass Spectrometry (HPLC/ESI/MS or 

HPLC/ESI/MS/MS). Available at http://www.epa.gov/SW-846 

USEPA, 2008, Method 314.2, Determination of Perchlorate in Drinking Water Using TowDimensional Ion Chromatography with Suppressed Conductivity Detection, Ver. 1.0. Available at 

www.epa.gov/safewater/methods/source.html. EPA Document No. 815-B-08-001 

Response: EPA will continue to evaluate the available science related to perchlorate, the feasibility 

of analytical methods, and the costs and benefits of regulation, as part of its decision making process 

to set an MCL for perchlorate. Please note, however, that SDWA excludes from EPA’s cost/benefit 

analysis the consideration of costs and benefits resulting from compliance with other regulatory 

programs. SDWA Section 1412(b)(3)(C). Please also see response to comment ID 28813 under 

comment code 6140. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0415 

EPA Comment ID: 28855 

EPA Comment Code: 6140 

 

Comment: Consideration of Studies Published since EPA adopted the NAS RfD for perchlorate 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1031 of 1099

In addition to the noted epidemiological, exposure assessment, and occurrence studies, AWWA 

would like to direct the Agency's attention to other references that should bear on the decision 

making process following this comment period. 

- AWWA and Water Research Foundation. 2009. Hypochlorite - An Assessment of Factors That 

Influence the Formation of Perchlorate and Other Contaminants. 

Considering that perchlorate has been under review for Federal regulation and is currently regulated 

in California and Massachusetts (proposed in New Jersey), this study was commissioned to quantify 

potential perchlorate contributions from hypochlorite sources. Sodium hypochlorite is a commonly 

used form of chlorine in drinking water and water reuse applications for its ability to disinfect and 

maintain a residual level of disinfectant throughout the distribution system. Approximately 1/3 of all 

drinking water treatment plants (DWTPs) in the United States use bulk hypochlorite for 

disinfection. [FN21: AWWA Disinfection Committee. 2008. Committee Report: Disinfection Survey 

Part 2 - Alternatives, experience and future plans. Journal AWWA. 100:11.] Though the majority of 

liquid hypochlorite use is in the form of bulk hypochlorite delivered from regional manufacturers 

and/or distributors, and some use on-site hypochlorite generators (OSG). 

The data set for this study was limited to 12 OSG sites, 6 bulk hypochlorite sites, and 1 calcium 

hypochlorite site. This sample set suggested no difference between bulk sodium hypochlorite 

solutions, OSG solutions, and calcium hypochlorite solutions with respect to chlorate and 

perchlorate ion concentration, with the exception being bromate formation. The analysis did 

demonstrate the potential to exceed some existing state standards and HRLs proposed by the 

Agency. Therefore, as more pressure is placed on utilities using gaseous chlorine to move towards 

alternative disinfection practices for security related reasons, the sector requires more detailed 

information to fully characterize potential differences (in terms of contaminant formation/dosing) 

between the available options to avoid unintended future water quality consequences and proper 

consideration of the risk- risk tradeoffs. 

- Russell, C., Roberson, A., Chowdhury, Z., and M. McGuire. 2009. National Cost Implications of a 

Perchlorate Regulation. Journal AWWA. 101:3:54. 

Recognizing a lack of available information on projected national costs associated with perchlorate 

treatment, a study was conducted to estimate the national cost implications of setting a federal 

maximum contaminant level (MCL) for perchlorate at different levels between 4 and 24 ug/L. At 

the most stringent potential MCL evaluated (4 ug/L), the national compliance cost was estimated to 

be between $76 and $140 million per year at a 3% discount rate. The relatively low national 

compliance cost for perchlorate reflects the small number of public water systems (PWSs) expected 

to be affected (3.4% at a perchlorate MCL of 4 ug/L based on 90th percentile perchlorate 

concentrations). However, the cost impacts to an individual system installing perchlorate treatment 

would likely be significant. With operations and maintenance (O&M) costs for perchlorate treatment 

over a 20-year period comparable to the capital costs for construction and with these O&M costs 

continuing in perpetuity, ratepayers could face a significant increase. 

Response: As the NPDWR is developed, economic feasibility will be evaluated in support of 

identifying an MCL. EPA will consider the best available, peer reviewed literature on the full range 

of issues embodied in an NPDWR, including risk-risk tradeoffs. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Commenter Name: Danielle Blacet 

Commenter Organization: Association of California Water Agencies 

EPA Document ID: EPA-HQ-OW-2009-0297-0208 

EPA Comment ID: 28920 

EPA Comment Code: 6140 

 

Comment: Since approximately 1/3 of all drinking water treatment plants (DWTPs) in the United 

States use bulk hypochlorite for disinfection, hypochlorite should be considered as a source of 

perchlorate contamination in finished drinking water.[FN2: AWWA and Water Research 

Foundation. 2009. Hypochlorite - An Assessment of Factors That Influence the Formation of 

Perchlorate and Other Contaminants.] Sodium hypochlorite is a commonly used form of chlorine in 

drinking water. Because the AWWA-WRF analysis demonstrated the potential to exceed some 

existing state standards and HRLs proposed by USEPA, the results of this study should be reviewed 

when finalizing the regulatory determination, and also included in the discussion regarding existing 

and future drinking water disinfection practices. 

Response: EPA is aware of this study and agrees that it should be considered in developing the 

NPDWR. 

Commenter Name: 

Commenter Organization: Intertox, Inc. 

EPA Document ID: EPA-HQ-OW-2009-0297-0662 

EPA Comment ID: 28938 

EPA Comment Code: 6140 

 

Comment: APPENDIX B 

INITIAL REVIEW OF HOPONICK ET AL., 2009 

Initial Review of: Hoponick JR, Melillo PR, Visser NT and Henshel DS. 2009. "Examining the 

Correlation between Perchlorate Concentrations in California Drinking Water and Low Birth 

Weight Percentage Using Population-Scale Regression Analysis," obtained from C. Matthews, 

Contractor, US EPA, Office of Environmental Information, EPA Docket Center, EPA Docket 

OW-2009-0297-0492, received via email on September 30, 2009.[FN1: 

http://www.regulations.govisearch/Regs/contentStreamer?objectld= 

0900006480a27182&disposition=attachment&contentType=xml] 

This document (Hoponick et al., 2009) appears to be a manuscript that has been submitted for 

publication. The study is an ecological epidemiological study, and is short in length. The authors 

evaluate the association between the mean perchlorate concentration measured in groundwater wells 

in 13 counties in California (measured between 1997 and 2004), and the percent of neonatal births 

with low birth weight (LBW), coded by zip code from 1993 to 2002. Zip code data sets for percent 

of births with LBW for each year were "averaged to the county level by averaging all data within 

each county." Based on this evaluation, the authors conclude that "log perchlorate data are 

significantly correlated with LBW for all years" and that "the increase is relatively linear from the 

lowest detectable perchlorate levels (3.3 ppb) to about 10 ppb, where the response appears to 

saturate." They further conclude, "Log perchlorate data also significantly positively correlates with 

TSH level for 1998, the only year for which TSH data was available." 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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An initial analysis of the manuscript was conducted using information derived from the manuscript. 

The source of data and an analysis of the methods and conclusions is provided below. Comments 

are divided into the following categories: data related to perchlorate concentrations in drinking 

water, data related to LBW, data related to neonatal TSH, and discussion of confounding factors. 

EPA should review the scientific basis of this manuscript to assure itself that the data are reliable. 

Upon request, additional information can be provided. What might be useful is to review a recently 

published paper which reports no effect on birth weight, head circumference, and body length 

associated with perchlorate exposure (Blount et al., 2009). Briefly, the following is noted regarding 

the manuscript. 

Perchlorate Concentrations in Drinking Water 

Hoponick et al. (2009) conducted statistical analyses using the mean concentrations of perchlorate in 

drinking water,[FN2: The paper alternatively calls the water source either "groundwater wells" or 

"drinking water wells."] collected between 1997 and September 9, 2004, and averaged across each of 

13 counties. The authors present mean concentrations for any California county that "contained two 

or more perchlorate detections from at least one drinking water source since 1997." Data were 

obtained from the California Department of Health Services website: 

http://www.cdph.ca.govicertlic/drinkingwater/Pages/Perchloratehistory.aspx. A downloadable MS 

Excel file of the data is here: 

http://www.cdph.ca.gov/certlic/drinkingwater/Documents/Perchlorate/Perchloratefo 

rwebearlyfindings.XLS. 

Some observations about these data are as follows: 

* The CDHS website only provides downloadable data for detects of perchlorate in water only. It is 

not clear from the manuscript whether the analysis considered nondetects in the calculation of mean 

perchlorate concentrations. 

* Neither the CDHS website nor the manuscript indicate the analytical method that was used to 

measure perchlorate during this time. For example, a change in analytical method could impact the 

concentration data. 

* The manuscript does not indicate the range of concentrations detected in the wells, the number 

and percentage of wells or water systems in which perchlorate was detected in each county, or how 

frequently perchlorate was detected in specific wells. 

* The data obtained from CDHS shows that many wells were sampled repeatedly. However, the 

manuscript does not indicate how multiple detections at the same location were considered in the 

calculation of the county average. 

* The manuscript does not indicate the extent to which sampled wells contribute to drinking water 

for the public in a given county, or whether water from wells was treated prior to distribution (but 

after sampling). 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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* Some of sample dates in the CDHS database cannot be discerned because they appear to be 

miscoded. 

* The manuscript does not indicate how the timing of sample collection was assumed to relate to the 

association with LBW data. 

* It appears that some average concentrations reported in the manuscript include data from wells 

designated in the CDHS database as "inactive" or "destroyed," and therefore would not contribute 

to drinking water that is distributed to the public. It is not clear how inclusion of these data is 

assumed to provide reliable measures of exposure. 

Percent of Neonatal Births with Low Birth Weight (LBW) 

Hoponick et al. (2009) report that data on neonatal birth weights were obtained from the California 

Department of Public Health (CDPH) for the years 1993 to 2002. The authors define "low birth 

weight" as a birth weight less than 2,500 grams (5.5 lbs.). The link provided in the paper redirects to 

here: http://ww2.cdph.ca.gov/programs/deodc/Pages/default.aspx. Annual data by zip code for 

the years 1993 to 2002 are available.[FN3: 1993: 

http://ww2.cdph.ca.gov/data/statistics/Documents/birthzip1993.xls 1994: 

http://ww2.cdph.ca.gov/data/statistics/Documents/birthzip1994.xls 1995: 

http://ww2.cdph.ca.gov/data/statistics/Documents/birthzip1995.xls 1996: 

http://ww2.cdph.ca.gov/data/statistics/Documents/birthzip1996.xls 1997: 

http://ww2.cdph.ca.gov/data/statistics/Documents/birthzip1997.xls 1998: 

http://ww2.cdph.ca.gov/data/statistics/Documents/birthzip1998.xls 1999: 

http://ww2.cdph.ca.gov/data/statistics/Documents/birthzip1999.xls 2000: 

http://ww2.cdph.ca.gov/data/statistics/Documents/birthzip2000.xls 2001: 

http://wv2.cdph.ca.gov/data/statistics/Documents/birthzip2001.xls 2002: 

http://ww2.cdph.ca.gov/data/statistics/Documents/birthzip2002.xls] 

Some initial observations of these data are as follows: 

* %LBW is lowest in 1996 for six of 13 counties and highest in 2002 for eight of 13 counties. The 

manuscript does not discuss these differences, or how they might relate to perchlorate exposure. For 

example, might there have been a change in the measurement or reporting method for birth weight? 

* Sacramento County has 135 zip codes, but in 2002 (for example) the CDPH data only includes 

birth weight data for 49 zip codes. Further, the CDHS data includes only 34 water samples for 

perchlorate (from a total of 14 locations in five systems), after exclusion of data from inactive or 

destroyed wells. It is not clear how from the manuscript how data from these wells was extrapolated 

to assumed exposure across the county, or to specific zip codes, and how birth weight data for 

missing zip codes was considered. It appears that all individuals in the county were assumed to be 

exposed to the average perchlorate concentration computed from the available samples, and that the 

county average %LBW was based on the 49 zip codes for which data were available. 

Neonatal TSH Data 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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The manuscript remarks "TSH data was obtained by contacting the CDHS directly, and 1998 was 

the only year CDHS provided." We were not able to find the data in the manuscript to support this 

statement. 

Confounding Factors 

The manuscript states, "The confounding factors data from 2003 was obtained from the California 

Interview Survey (CHIS) Database, which is operated by the University of California Los Angeles 

Center for Health Policy Research, in cooperation with CDHS and the Public Health Institute." The 

CHIS database is available (http://www.chis.ucla.edu/getdata.html). The only confounding variables 

reportedly considered by the authors were race and percentage of uninsured individuals. However, 

the literature on low birth weight is extensive and many other factors are known to influence birth 

weight including maternal health status, maternal age, smoking, alcohol/ drug use, prenatal care, 

maternal education level, and other socio-economic factors (Bailey and Byrom, 2007; Nobile et al., 

2007). It appears that these factors were not evaluated. 

References 

Bailey BA, Byrom AR. 2007. Factors predicting birth weight in a low-risk sample: the role of 

modifiable pregnancy health behaviors. Matern Child Health J11(2):173-9. 

Blount BC, Rich DQ, Valentin-Blasini L, Lashley S, Ananth CV, Murphy E, Smulian JC, Spain BJ, 

Barr DB, Ledoux T, Hore P, Robson M. 2009. Perinatal Exposure to Perchlorate, Thiocyanate, and 

Nitrate in New Jersey Mothers and Newborns. Environ Sci Technol [Epub ahead of print]. 

Nobile CG, Raffaele G, Altomare C, Pavia M. 2007. Influence of maternal and social factors as 

predictors of low birth weight in Italy. MC Public Health 7:192. 

Response: EPA will use the best available, peer reviewed science in preparing the NPDWR for 

perchlorate. 

Commenter Name: Tom Porta 

Commenter Organization: Nevada Division of Environmental Protection (NDEP) 

EPA Document ID: EPA-HQ-OW-2009-0297-0638 

EPA Comment ID: 29100 

EPA Comment Code: 6140 

 

Comment: The August 19, 2009 Federal Register Notice indicates that EPA is considering using 

monitoring data from the State of Massachusetts to help characterize the distribution of very low 

perchlorate concentrations occurrences. Evidence needs to be provided to support the use of 

Massachusetts (or other discrete) monitoring data for the purpose indicated. EPA has not 

demonstrated how these data sets are representative of the nation as a whole. Model calibration 

should be conducted with robust data that are representative of the nation's water supply systems to 

make informed decisions regarding a national primary drinking water standard. Consequently, the 

NDEP recommends collection of new data for perchlorate in public water systems, coupled with 

the use of more sensitive analytical methods with greater specificity (EPA Method 331 or EPA 

Method 332). Newer, more sensitive analytical methods will provide more reliable and robust data, 

rather than trying to estimate values (< 4 ug/L) that are not part of the existing, outdated occurrence 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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data generated using a less sensitive analytical method (EPA Method 314). The referenced more 

sensitive methods have several method refinements (different column packing material, longer 

columns, mass spectrometry detectors) that lead to fewer false positives or false negatives and 

permit perchlorate analysis with reporting limits (detection limits) at or below 1 ug/L. These newer 

data are more robust and capable of multiple uses without limitations inherent in estimated data. 

Response: EPA agrees that newer analytical methods are more sensitive. Information from a variety 

of sources will be used in developing the NPDWR. EPA is required to use the best available, peer 

reviewed science in its deliberations. The strengths and limitations will be considered as those 

deliberations proceed. 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 6200 Comments related to EPA’s health advisory 

Individual Comments 

Commenter Name: Kathy M. Kinsey 

Commenter Organization: Maryland Department of the Environment 

EPA Document ID: EPA-HQ-OW-2008-0692-1421 

EPA Comment ID: 20428 

EPA Comment Code: 6200 

 

Comment: A Health Advisory for Perchlorate Will Undermine Cleanup Efforts 

The establishment of a uniform federal standard is especially important to eliminate potentially 

conflicting state standards, particularly in cases of cross-boundary contamination. Merely publishing 

a health advisory for perchlorate, as EPA has proposed, will undermine expeditious cleanup of 

contaminated sites and regulation of discharges to interstate surface waters used to supply drinking 

water. A health advisory is not binding or enforceable, and does not ensure a uniform nationwide 

standard. Rather, it leads to a patchwork of different state standards and in the absence of a state 

standard, cleanup standards for individual sites that must be established through negotiation on a 

case-by-case basis. 

Response: See response to comment ID 28479 under comment code 6200. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association 

EPA Document ID: EPA-HQ-OW-2008-0692-1424 

EPA Comment ID: 20441 

EPA Comment Code: 6200 

 

Comment: Health Advisory 

AWWA supports the EPA decision to issue a Health Advisory for perchlorate at the timeof the final 

determination. Health advisories provide important technical guidance to Federal agencies, State 

governments, and other public health officials on health effects, analytical methodologies, and 

treatment technologies. EPA should, in parallel, issue are vision of the "Assessment Guidance for 

Perchlorate" released by the Office of Solid Waste and Emergency Response (OSWER) on January 

26, 2006, which defines the remediation goal for perchlorate in accordance with National Oil and 

Hazardous Substances Contingency Plan (National Contingency Plan, NCP), 40 CFR Part 300. In 

addition, any potential remediation action should consider all applicable or relevantand appropriate 

(ARAR) requirements under federal environmental or state environmental or facility siting laws. 

Response: See response to comment ID 28479 under comment code 6200. A Health Advisory will 

no longer be needed. 

Commenter Name: Ed Thomas 

Commenter Organization: National Rural Water Association 

EPA Document ID: EPA-HQ-OW-2008-0692-1669 
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EPA Comment ID: 20618 

EPA Comment Code: 6200 

 

Comment: Based on the occurrence, health risk, and related findings presented in the Agency’s 

analysis we also believe that a health advisory is appropriate. It is evident that perchlorate is a 

problem in specific targeted areas. A health advisory will provide the acceptable levels that are safe 

for local communities with contaminated source water. 

Response: See response to comment ID 28479 under comment code 6200. A Health Advisory will 

not be needed. 

Commenter Name: Paul J., P.E. Ponturo 

Commenter Organization: Long Island Water Conference 

EPA Document ID: EPA-HQ-OW-2008-0692-1260 

EPA Comment ID: 20624 

EPA Comment Code: 6200 

 

Comment: In the preliminary determination, EPA has indicated that States that are known to have 

perchlorate concentrations at or above the HRL should develop their own regulations, and has 

stated its intent to provide the States with a Health Advisory Level at the same time it finalizes this 

determination. We wish to state for the record that we will ask the State of New York for an 

enforceable MCL to be adopted. The Long Island Water Conference's member suppliers are fully 

supportive of science-driven regulations that are most protective of public health, and to that end 

have in some cases voluntarily installed treatment or modified operational practices to reduce the 

use of wells containing perchlorate. 

Response: See response to comment ID 28479 under comment code 6200. 

Commenter Name: James Taft 

Commenter Organization: Association of State Drinking Water Agencies 

EPA Document ID: EPA-HQ-OW-2008-0692-1527 

EPA Comment ID: 20635 

EPA Comment Code: 6200 

 

Comment: A Health Advisory is step one - If the Agency is not going to develop a full national 

regulation, it needs to provide adequate support for those entities (water systems and states) that are 

going to respond at the local level. In the Federal Register notice, EPA committed to publishing a 

health advisory for perchlorate at the time of the final determination in order to provide information 

regarding potential health risks from perchlorate-contaminated drinking water. States fully support 

this action and recommend that the Agency provide the health advisory as soon as possible. While 

this may be enough to help states and water systems determine when perchlorate is approaching 

levels of health concern, it will not provide the level of technical support necessary for states and 

water systems to address perchlorate contamination problems. 

Response: See response to comment ID 28479 under comment code 6200. 

Commenter Name: Mic Stewart 

Commenter Organization: Metropolitan Water District of Southern California 
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EPA Document ID: EPA-HQ-OW-2008-0692-1784 

EPA Comment ID: 20663 

EPA Comment Code: 6200 

 

Comment: * Public Health Advisory for Perchlorate - Metropolitan recommends that any public 

health advisory for perchlorate in drinking water issued by the EPA include language that provides 

the greatest possible public health protection, particularly for pregnant women and other sensitive 

sub-populations (e.g., infants and children). 

Response: See response to comment ID 28479 under comment code 6200. A Health Advisory will 

not be needed. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1855 

EPA Comment ID: 21102 

EPA Comment Code: 6200 

 

Comment: IX. EPA Should Make Conforming Changes to its Regulation and Policies Consistent 

with this Determination 

At the same time of its final determination, EPA should maintain its March 2006 guidance for use 

by EPA regions and states, but update it with the new Health Advisory, if the decision is made to set 

one. The RfD is a conservative safe dose as has been noted throughout our comments. The current 

guidance allows state and local officials to factor in site-specific considerations and populations as 

opposed to making local decisions guidance data based upon nationally representative exposure data. 

Issuing a health advisory and revised guidance at the same time as the agency issues a final 

determination provides a strong clear message from EPA headquarters to EPA regions as well as 

state and local public health officials on the final federal policy related to perchlorate. It brings to 

close any uncertainty at the federal level on the issue, thereby providing state and local officials with 

regulatory certainty and allowing them to move forward in addressing site-specific contamination. 

Response: See response to comment ID 28479 under comment code 6200. A Health Advisory will 

not be needed. 

Commenter Name: Ed Thomas 

Commenter Organization: National Rural Water Association (NRWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0521 

EPA Comment ID: 28475 

EPA Comment Code: 6200 

 

Comment: Based on the occurrence, health risk, and related findings presented in the Agency’s 

analysis we also believe that a health advisory is appropriate. It is evident that perchlorate is a 

problem in specific targeted areas. A health advisory will provide the acceptable levels that are safe 

for local communities with contaminated source water. 

Response: See response to comment ID 28479 under comment code 6200. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Commenter Name: Mark S. Mayer 

Commenter Organization: South Dakota Department of Environment & Natural Resources 

(DENR) 

EPA Document ID: EPA-HQ-OW-2009-0297-0467 

EPA Comment ID: 28479 

EPA Comment Code: 6200 

 

Comment: - Where Perchlorate is a problem, it is important that EPA provide resources to those 

states to appropriately and consistently respond. The first step should be for EPA to establish a 

health advisory that can be used to identify potential problems at the local level. 

Response: EPA has determined the need to regulate perchlorate and will develop a NPDWR. As a 

result, a health advisory will not be necessary. 

Commenter Name: James D. Taft 

Commenter Organization: Association of State Drinking Water Administrators 

EPA Document ID: EPA-HQ-OW-2009-0297-0525 

EPA Comment ID: 28505 

EPA Comment Code: 6200 

 

Comment: A Health Advisory is step one - If the Agency is not going to develop a full national 

regulation, it needs to provide adequate support for those entities (water systems and states) that are 

going to respond at the local level. In the October 2008 Federal Register notice, EPA committed to 

publishing a Health Advisory for perchlorate at the time of the final determination in order to 

provide information regarding potential health risks from perchlorate- contaminated drinking water. 

States fully support this action and recommend that the Agency finalize the interim January 2009 

health advisory as soon as possible. ASDWA also recommends that EPA prepare educational 

materials to help states and water systems use the Health Advisory to educate the public about 

perchlorate in the systems where it is detected. 

Thank you for your consideration of these comments. Please contact me at 703-812-9507 or 

jtaft@asdwa.org if we can provide additional information or if any clarification of these comments is 

needed. 

Sincerely, James D. Taft Executive Director 

Response: See response to comment ID 28479 under comment code 6200. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0494 

EPA Comment ID: 28832 

EPA Comment Code: 6200 

 

Comment: In addition, if EPA chooses to update its health advisory, AMWA recommends that the 

agency take care to explain the difference between perchlorate and other chemical compounds. 

Perchlorate is an endocrine disruptor and in the words of one peer reviewer, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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"However, as noted above, what is still needed at the beginning of the document is a brief overview 

of the toxicokinetics of perchlorate, iodine as an essential element for the synthesis of thyroid 

hormones, why thyroid hormone sufficiency is important, what homeostasis is - perchlorate affects a 

self-regulating system which has evolved numerous feedback mechanisms to compensate for 

deficiency induced by inadequate intake, iodine uptake inhibition, illness and that within the 

homeostatic range, which is robust in humans, this system is successful. [The same would be true for 

excess.] In other words, the biological impacts of perchlorate are very different from those for 

chemical compounds which have direct target organ toxicity and/or do not directly affect the 

availability of an essential element for which homeostasis occurs." (EPA, 2008. Comment- Response 

Summary Report. Peer Review of Drinking Water Health Advisory for Perchlorate, page 7). 

Response: EPA agrees that this suggested information should be incorporated into support 

documentation for the impending NPDWR. 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 6210 Need for EPA to provide additional support to 

States and water systems 

Individual Comments 

Commenter Name: Paul J., P.E. Ponturo 

Commenter Organization: Long Island Water Conference 

EPA Document ID: EPA-HQ-OW-2008-0692-1260 

EPA Comment ID: 20625 

EPA Comment Code: 6210 

 

Comment: However we wish to point out that those States that need to develop their own 

standards, potentially as many as 26 according to the preliminary determination, will need to make 

other complex decisions beyond establishing an MCL. EPA knows the importance of a fully-formed 

regulation that is legally defendable. To that end decisions will need to be made as to acceptable 

analytical methodologies, best available treatment technology and treatment residuals disposal, 

minimum analytical frequencies, and perchlorate occurrence processes. It should also be recognized 

that companion regulations will need to be developed to identify and restrict industrial applications 

and storage of chemicals containing perchlorate. Unmeasured perchlorate may exist in products in 

common use, yet the users may be unaware of a potential concern. As previously stated, many 

perchlorate detections do not trace to known sources. 

Therefore we do wish to state our concern that states may lack the resources to develop a robust 

regulatory response to their individual perchlorate issues. We would respectfully request that EPA's 

guidance to the states should also incorporate a Federal resource commitment to the other aspects 

of the regulatory problem that the states will have to face. EPA should also continue to be a clearing 

house of information on perchlorate and commit research dollars to encourage the development of 

economically viable treatment alternatives, and to better understand perchlorate occurrence. 

The Conference appreciates your consideration of these comments and looks forward to seeing the 

continued development of this important regulation. 

Very truly yours, Kenneth S. Claus Chairman, Long Island Water Conference 

Response: See the response to comment code 6120. EPA acknowledges commenter’s concern 

about decisions that will need to be made as to acceptable analytical methodologies, best available 

treatment technology and treatment residuals disposal, minimum analytical frequencies, and 

perchlorate occurrence processes. These issues are factors that EPA will consider when developing a 

NPDWR for perchlorate. Upon promulgating a NPDWR, EPA will provide States and public water 

systems with information in regards to perchlorate treatment techniques. EPA acknowledges 

commenter’s statement “...It should also be recognized that companion regulations will need to be 

developed to identify and restrict industrial applications and storage of chemicals containing 

perchlorate.” However this subject matter pertains to EPA’s RCRA regulations and falls outside of 

the scope of this regulatory action. 

Pursuant to SDWA section 1412(b)(4)(E), 42 USC 300g-1(b)(4)(E), when EPA publishes a NPDWR 

establishing an MCL, the Administrator must list technologies, treatment techniques, and other 

means that the Administrator finds feasible for meeting the MCL, and: 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1043 of 1099

The Administrator shall include in the list any technology, treatment technique, or other means that 

is affordable, as determined by the Administrator in consultation with the States, for small public 

water systems serving-- 

(I) a population of 10,000 or fewer but more than 3,300; 

(II) a population of 3,300 or fewer but more than 500; and 

(III) a population of 500 or fewer but more than 25; 

and that achieves compliance with the maximum contaminant level or treatment technique, 

including packaged or modular systems and point-of-entry or point-of-use treatment units. 

Commenter Name: James Taft 

Commenter Organization: Association of State Drinking Water Agencies 

EPA Document ID: EPA-HQ-OW-2008-0692-1527 

EPA Comment ID: 20636 

EPA Comment Code: 6210 

 

Comment: Provide additional guidance to support states and water systems - In addition to the 

health effects, systems will need to know what treatments are effective for various types of source 

water and levels of perchlorate. Systems will also need information to help them evaluate nontreatment alternatives to perchlorate control (if available). ASDWA would be willing to work with 

EPA and other partners to determine what supporting materials should be developed. 

Thank you for your consideration of these comments. We feel that perchlorate is somewhat of a 

special case due to its high profile and potential for causing adverse health effects and therefore 

deserves something beyond just a health advisory to support state drinking water programs. We 

hope the Agency will be willing to take these additional steps and we are ready to help develop a 

reasonable plan. Please contact me at 703-812-9507 or jtaft@asdwa.org if we can provide additional 

information or if any clarification of these comments is needed. 

Sincerely, James D. Taft Executive Director 

Response: EPA agrees and has decided to regulate perchlorate in drinking water. See response to 

comment code 6120. Pursuant to statutory requirements, EPA intends to publish and seek public 

comment on technology, treatment techniques, and other means which the Administrator finds to 

be feasible for purposes of meeting the proposed maximum contaminant level. The proposed 

regulation will also include an assessment of alternative treatment techniques that EPA is 

considering. 

Commenter Name: Tina Carroll 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2189 

EPA Comment ID: 22382 

EPA Comment Code: 6210 

 
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Comment: I am deeply concerned that there known sources of perchlorate contamination in our 

area and the EPA has chosen to do nothing about it. All Americans deserve healthy and clean 

drinking water and I urge you to reverse your decision and to set a national drinking water standard 

for perchlorate. 

Sincerely, Tina Carroll 3253 Chestnut Avenue Baltimore, MD 21211 

Response: EPA has decided to regulate perchlorate in drinking water. See response to comment 

code 6120. 

Commenter Name: Mark S. Mayer 

Commenter Organization: South Dakota Department of Environment & Natural Resources 

(DENR) 

EPA Document ID: EPA-HQ-OW-2009-0297-0467 

EPA Comment ID: 28480 

EPA Comment Code: 6210 

 

Comment: - Where Perchlorate is a problem, it is also important that EPA provide technical 

information on effective treatment options for various source waters and levels of Perchlorate. 

Response: EPA has determined that regulation of perchlorate in drinking water systems presents a 

meaningful opportunity to reduce health risk for persons served by public water systems. This action 

initiates the process to establish a national primary drinking water regulation (NPDWR) for 

perchlorate. EPA will provide an evaluation of feasible treatment technologies and small system 

compliance techniques as part of the proposed NPDWR. 

Commenter Name: James D. Taft 

Commenter Organization: Association of State Drinking Water Administrators 

EPA Document ID: EPA-HQ-OW-2009-0297-0525 

EPA Comment ID: 28504 

EPA Comment Code: 6210 

 

Comment: Additional issues - In closing, we would like to recap some of our previous comments 

related to the regulation of perchlorate. These are still valid points and need to be considered, 

regardless of what final determination is made. 

Regardless of EPA's regulatory decision, states will need to act - Even if EPA does not adopt a 

national regulation of perchlorate, the public will likely demand a response to detections of elevated 

levels of perchlorate - particularly, in light of the notoriety associated with this contaminant. In states 

where there are detections of perchlorate at levels of concern, drinking water programs need to be 

able to respond appropriately so that public health can be protected. At a minimum, states will need 

to assist individual water systems with the specific actions needed to control perchlorate. 

Information is needed from EPA on risk characterization and risk management as well as treatment 

options and alternative control measures to support state efforts. In some cases, a state may decide 

that perchlorate is common enough in their source waters that they are interested in developing 

statewide measures, whether it is a formal monitoring program or a state specific MCL. We believe 

the Agency has data and expertise that can help support these actions. 
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Response: EPA agrees and has decided to regulate perchlorate in drinking water. See response to 

comment code 6120 and response to comment ID 20634 under comment code 6130. 

Commenter Name: Danielle Blacet 

Commenter Organization: Association of California Water Agencies 

EPA Document ID: EPA-HQ-OW-2009-0297-0208 

EPA Comment ID: 28921 

EPA Comment Code: 6210 

 

Comment: 3) Colorado River implications 

As USEPA is aware, much of Southern California depends on a reliable water supply from the 

Colorado River, and our members actively participate with other Colorado River basin states to help 

ensure the delivery of a quantity and quality of water that will meet our environmental, urban and 

agricultural needs. This situation has become even more critical with the recent droughts in the 

Colorado River basin and California. 

ACWA strongly recommends that during its science-based review and ultimate regulatory 

determination for perchlorate, USEPA remains cognizant of the sources and impacts from interstate 

perchlorate contamination to all California utilities, particularly those that rely on the Colorado 

River. This especially is relevant to agricultural use of Colorado River water and concentration of 

perchlorate in produce shipped nationwide. We would like to work with USEPA on ways to address 

this very important issue. 

Response: EPA has determined that regulation of perchlorate in drinking water systems presents a 

meaningful opportunity to reduce health risk for persons served by public water systems. See 

response to comment code 6120. This action initiates the process to establish a national primary 

drinking water regulation (NPDWR) for perchlorate. In developing the proposed national primary 

drinking water standard, EPA will consider the degree to which perchlorate is present in public 

water supplies in all systems throughout the U.S. EPA intends to publish the proposed NPDWR for 

public comment along with health risk reduction and cost analysis, feasibility analysis and other 

analyses required for regulatory development under the SDWA. EPA will consider comments on the 

proposed NPDWR and then promulgate the final regulation. 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 6300 EPA's intention to revise guidance on clean-up 

levels (preliminary remediation goals) 

Response to Code 6300: While EPA recognizes that perchlorate has been a contaminant of 

concern at a number of sites that have (or may in the future) require cleanup, it is not appropriate 

for the Agency to establish national primary drinking water regulations for the purpose of 

establishing cleanup levels at contaminated sites. Rather, the Safe Drinking Water Act specifies the 

criteria which compels regulation of a contaminant. EPA must determine that the contaminant 

meets three criteria: 1) the contaminant may have an adverse effect on human health, 2) the 

contaminant is known to occur or there is a substantial likelihood that the contaminant will occur in 

public water systems with a frequency and at levels of public health concern, and 3) in the sole 

judgment of the Administrator, regulation of such contaminant presents a meaningful opportunity 

for the reduction of health risks from perchlorate for persons served by public water systems. We 

would note, however, that on January 8, 2009, EPA issued guidance that revised the preliminary 

remediation goal (PRG)[Footnote] for perchlorate in soil from 24.5 ug/L to 15/ug/L, which states 

that where no federal or state applicable or relevant and appropriate (ARAR) requirements exist 

under federal or state laws, 15 ug/L is recommended as the PRG for perchlorate when making 

CERCLA site-specific cleanup decisions where there is an actual or potential drinking water 

exposure pathway (http://www.epa.gov/fedfac/documents/perchlorate_memo_01-08-09.pdf). 

Depending on EPA's final decision regarding a national primary drinking water standard for 

perchlorate, the Agency may modify this guidance. 

Footnote: PRGs are not cleanup levels, but are specific statements of desired endpoint 

concentrations or risk levels (55 FR 8713 (March 8, 1990)) that are conservative, default endpoint 

concentrations used in screening and initial development of remedial alternatives before 

consideration of information from the site-specific risk assessment. 

Individual Comments 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0166 

EPA Comment ID: 20276 

EPA Comment Code: 6300 

 

Comment: AMWA believes that factors other than those discussed in the notice need to be 

considered. The contamination of water supplies by perchlorate is on-going, since perchlorate is still 

in use at various DoD sites, airfields and rocket manufacturing facilities. In addition, because there is 

no cleanup standard, perchlorate that has entered the soil and contaminated aquifers will likely 

spread, leading to additional impacted sites. 

When a contaminant is polluting drinking water supplies and the lack of a standard is impeding 

pollution prevention and cleanup, then an appropriate course of action is needed. Several of the 

contaminants in the notice deemed appropriate for a determination not to regulate are pesticides 

that have not been produced or used for decades and have low and decreasing occurrence levels. 

Perchlorate, on the other hand, is still in use and is expected to have increasing occurrence levels as 

contamination migrates from soils to ground water aquifers, potentially resulting in impacts on 

increasing numbers of water systems - clearly a call for action. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Response: See response to comment code 6300. The Agency has determined that the three SDWA 

criteria for regulatory determination have been met for perchlorate. See response to commend code 

6120. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: AMWA 

EPA Document ID: EPA-HQ-OW-2008-0692-1525 

EPA Comment ID: 20445 

EPA Comment Code: 6300 

 

Comment: Cleanup Standards 

AMWA agrees with the agency that guidance regarding perchlorate and cleanup levels under the 

National Oil and Hazardous Substances Contingency Plan (National Contingency Plan, NCP) 

should be revised downward from the present preliminary remediation goal (PRG) of 24.5 ppb. 

AMWA believes, however, that an appropriate PRG to protect drinking water and it users should 

assume that contaminated water sources would be used as drinking water. Perchlorate contaminated 

sites should be cleaned up to some fraction of the HRL (such as two-thirds or 10 ppb) so that any 

levels consumed are reliably and consistently below the HRL. 

Since the recommended PRG generally is the starting point for determining appropriate site-specific 

cleanup levels, AMWA believes it is appropriate to start at levels that allow a margin of safety with 

respect to the HRL to account for the variable nature of continuing contamination and occurrence 

fluctuations. The level could then be adjusted up or down depending upon the site specifics. The 

PRG based on the HRL should not supplant more stringent state standards. 

Response: See response to comment code 6300. 

Commenter Name: Thomas L. Schoaf 

Commenter Organization: Cities of Litchfield Park and Goodyear, AZ 

EPA Document ID: EPA-HQ-OW-2008-0692-1552 

EPA Comment ID: 20555 

EPA Comment Code: 6300 

 

Comment: Historical industrial operations have impacted the aquifer in the PGA North Superfund 

Site with TCE and perchlorate. The EPA Region 9 is currently overseeing a private party financed 

cleanup of the TCE impacted groundwater at the site. The remedy consists of several independent 

groundwater pump-and-treat systems. The treated water is either used as an irrigation supply or 

reinjected into the aquifer. Future remedies being considered to address the currently expanding 

TCE plume may entail providing the treated water for drinking water purposes. Where groundwater 

is being reinjected to the aquifer, EPA Region 9 is requiring the private party to treat for perchlorate 

as well as TCE in order to avoid aquifer degradation in areas not impacted by the plume. However, 

no treatment is required for water used as an irrigation supply. Since perchlorate, unlike TCE, has no 

established standard, EPA 9 is relying on guidance and "To Be Considered" criteria to require 

treatment of reinjected water at the PGA-North Superfund Site. Without the strength of a 

promulgated standard, we are concerned that EPA Region 9 will not be able to ensure that future 

remedies require perchlorate treatment. Further, guidance levels and To Be Considered criteria may 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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not provide EPA Region 9 the necessary authority to require that the responsible party implements 

an effective remedy to address the historical perchlorate contamination in the aquifer-our future 

water supply. 

Response: See response to comment code 6300. 

Commenter Name: Mic Stewart 

Commenter Organization: Metropolitan Water District of Southern California 

EPA Document ID: EPA-HQ-OW-2008-0692-1784 

EPA Comment ID: 20664 

EPA Comment Code: 6300 

 

Comment: * Applicable or Relevant and Appropriate Requirements (ARARs) - While California has 

a drinking water MCL of 6 ppb for perchlorate, Metropolitan suggests that given any decision by the 

EPA not to regulate perchlorate, the ARARs called for in regulatory cleanup be set at the drinking 

water standard in states with an MCL for perchlorate. This would provide cleanup guidance for 

contaminated sites. 

* Site specific cleanup levels - EPA states that the Health Advisory value can be used as a "to be 

considered value" for developing cleanup levels for perchlorate contaminated sites (i.e., Superfund). 

The Health Advisory value that should be stipulated in the final health advisory document will be set 

at a level to provide protection to the population. Sites that are potential sources of drinking water, 

or impact sources of drinking water, should be required to treat to a level that protects the 

population. A "to be considered" criteria for clean-up levels is not adequate to provide protection to 

the public. 

Metropolitan appreciates this opportunity to provide input on the proposed regulatory 

determination for perchlorate and asks that EPA carefully consider these comments before 

publishing the final rule. Please contact me at (213) 217-5696 if you have any questions, or if I can 

provide additional information. 

Very truly yours, Mic Stewart, PhD Manager, Water Quality Section 

Response: See response to comment code 6300. The Agency has determined that the three SDWA 

criteria for regulatory determination have been met for perchlorate. See response to commend code 

6120. 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 6310 Clean up as a solution 

Individual Comments 

Commenter Name: Kay Brothers 

Commenter Organization: Southern Nevada Water Authority 

EPA Document ID: EPA-HQ-OW-2009-0297-0648 

EPA Comment ID: 28495 

EPA Comment Code: 6310 

 

Comment: October 8, 2009 

Water Docket Environmental Protection Agency Mailcode: 2822T 1200 Pennsylvania Avenue, NW 

Washington, DC 20460 

SUBJECT: Comments on the Drinking Water: Percholorate Supplemental request for Comments 

Docket ID No. EPA-HQ-OW-2009-0297 

The Southern Nevada Water Authority (Authority) submitted detailed comments, dated September 

17, 2009, on the preliminary regulatory determination for perchlorate as listed in the August 19, 

2009 Federal Register (74FR41883). We would like to submit the following additional comments 

regarding the Authority's commitment to ensure that perchlorate clean-up efforts continue along the 

Las Vegas Wash (Wash) upstream from Lake Mead. 

As outlined in our comments previously submitted, perchlorate clean-up efforts in the Wash have 

significantly decreased the levels of perchlorate in Lake Mead and the lower Colorado River system. 

Tronox, Inc., (Tronox) owns the facility in Henderson, Nevada that produced perchlorate from 

1952-2002. The site is the source of perchlorate contamination of groundwater that enters the Wash 

(which empties into the Colorado River). Currently, the contaminated water is intercepted at the 

Wash, treated in a remediation system financed by Tronox, and discharged into the Wash. The 

system is operated at the direction of the Nevada Division of Environmental Protection (NDEP), 

which estimates the current annual cost of operation at $6,000,000 with a potential remediation span 

of 100 years. On January 12, 2009, Tronox filed a petition for reorganization in United States 

Bankruptcy Court for the Southern District of New York. 

The Authority, in order to actively participate in the litigation and to protect its strong interest in 

continued groundwater remediation and eventual elimination of the source of perchlorate 

contamination, hired the New York City bankruptcy firm of Kramer Levin Naftalis & Frankel. The 

Authority has filed a proof of claim, is examining the terms of a proposed sale of the Henderson 

site, and is working in concert with the Metropolitan Water District of Southern California (MET) 

and the Central Arizona Water Conservation District (CAP) to ensure that remediation efforts 

receive an adequate accounting and future funding. 

To summarize, the Authority in concert with the NDEP and our partners, CAP and MET, are 

committed to ensuring the clean-up of perchlorate continues along the Wash. If you have any 

questions regarding our comments, please contact me directly at (702) 862-3707. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Sincerely, Kay Brothers Deputy General Manager Engineering and Operations 

KB/df 

cc: Jeffrey Kightlinger, General Manager - Metropolitan Water District of Southern California David 

Modeer, General Manager - Central Arizona Project 

Response: No response necessary for this comment. 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 6400 EPA's decision to subject updated PBPK model to 

peer review during comment period (in the October 2008 FR Notice) 

Response to Code 6400: EPA reviewed, modified, and applied the perchlorate PBPK models, 

which were originally developed by Merrill et al. (2005) for adults and Clewell et al. (2007) for other 

life stages, to estimate the iodide uptake inhibition in the thyroid for each life-stage (73 FR 60262). 

Estimated ingestion rates were then used to estimate the internal dose and resulting iodide uptake 

inhibition for several life stages, including susceptible populations (e.g., pregnant women and their 

fetuses, as well as breast-fed and bottle-fed infants). 

The draft report, “Inhibition of the Sodium-Iodide Symporter by Perchlorate: An Evaluation of 

Lifestage Sensitivity Using Physiologically-based Pharmacokinetic (PBPK) Modeling,” underwent a 

formal external peer review by eight experts in accordance with EPA guidance concurrently with the 

public comment period. Based on the external peer review comments, the models and report were 

revised. The final report, peer review report, and a summary of peer review comments and EPA 

responses are available at http://cfpub.epa.gov/ncea/cfm/recordisplay.cfm?deid=199347. 

In the August 2009 notice, EPA stated that it was re-evaluating how best to incorporate the PBPK 

modeling analysis into its evaluation of perchlorate — if at all. The Agency sought comments on 

ways to use the PBPK modeling analysis to inform the regulatory determination. 

After further consideration of the peer review and public comments, EPA concludes that the PBPK 

modeling analysis, in the context of the perchlorate regulatory determination, is useful in examining 

which life stages are most susceptible to the effects of perchlorate. However, because of the stated 

limitations, EPA has decided the model does not directly bear on the current decision regarding the 

need for a NPDWR for perchlorate. EPA is continuing to evaluate whether the model could be used 

in setting a NPDWR for perchlorate. 

Individual Comments 

Commenter Name: Diane VanDe Hei 

Commenter Organization: AMWA 

EPA Document ID: EPA-HQ-OW-2008-0692-1525 

EPA Comment ID: 20443 

EPA Comment Code: 6400 

 

Comment: November 10, 2008 

Water Docket U.S. Environmental Protection Agency Office of Water Docket (Mailcode 2822T) 

1200 Pennsylvania Ave. NW Washington, DC 20460 

RE: Drinking Water: Preliminary Regulatory Determination on Perchlorate; Docket EPA-HQ-OW2008-0068 

Dear Water Docket: 

AMWA appreciates the opportunity to comment on the preliminary regulatory determination for 

perchlorate as listed in the October 10, 2008 Federal Register (73 FR 60262). AMWA strongly 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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supports the process required by the 1996 Amendments of the Safe Drinking Water Act that places 

a strong emphasis on science and focuses on contaminants which: may have an adverse effect on 

humans, occur or are likely to occur at levels of public health concern and provide a meaningful 

opportunity for health risk reduction. 

Members of Congress, the Administrator and the public have all weighed in on the need to regulate 

perchlorate. Concern over the lack of a regulatory path forward coupled with differing 

interpretations of the available scientific information has led to significant controversy. In such an 

environment, decisions need to be supported by peer reviewedscience to garner general acceptance. 

Accordingly, AMWA has several recommendations for the agency concerning peer review, review 

by the National Academy of Sciences (NAS), retention on the Contaminant Candidate List (CCL), 

the need for a strong cleanup standard, and other considerations. The remainder of these comments 

will address each in turn. 

Peer-Review 

In the Federal Register Notice, EPA expresses its intention to subject several key scientific points 

used in the decision process to peer-review before finalizing the determination. The agency notes 

that adjustments have been made to a previously peer-reviewed physiologically based 

pharmacokinetic (PBPK) model for predicting iodide uptake for several sensitive subpopulations. 

Additionally, the agency feels that it is pertinent to have a peer-review panel consider the 

appropriateness of the model for addressing non-adult populations. AMWA agrees that such 

reviews are appropriate and necessary. However, the agency should assure that peer review panel 

questions are posed so that the usefulness of the model is explored with specific regard to the most 

sensitive subpopulations. Specifically, detailed comment should be solicited on whether the lack of 

data on early fetal radioactive iodide uptake inhibition would be expected to affect the agency’s 

determination that a Health Reference Level (HRL) of 15 ppb is protective of pregnant women and 

fetuses. 

Response: See response to comment code 6400. 

Commenter Name: Robert Howd 

Commenter Organization: California Environmental Protection Agency, Water Toxicology 

Section 

EPA Document ID: EPA-HQ-OW-2008-0692-1671 

EPA Comment ID: 20645 

EPA Comment Code: 6400 

 

Comment: FROM: Robert A. Howd California Environmental Protection Agency, Office of 

Environmental Health Hazard Assessment 

November 7, 2008 

Water Docket Environmental Protection Agency Mailcode: 2822T 1200 Pennsylvania Ave., NW 

Washington, DC 20460 

Subject: Comments to Docket ID No. EPA-HQ-OW-2008-0068 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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To Whom It May Concern: 

Thank you for providing the opportunity to comment on the Federal Register announcement of 

Friday, October 10, 2008, titled "Drinking Water: Preliminary Regulatory Determination on 

Perchlorate" (FR 73, no. 198, pp. 60262- 82). These comments were prepared by the Water 

Toxicology Section of the California Office of Environmental Health Hazard Assessment. 

II(D), p 60265. EPA states that its regulatory determination on perchlorate has been based in part 

on a PBPK model with adjustments made by EPA that have not been peer reviewed (U.S. EPA, 

2008). Some of the adjustments, including perchlorate inhibition of fetal iodide uptake, are critical to 

the interpretation. We recommend that such a peer review, plus opportunity for public comment on 

the model, be carried out before EPA publishes its final determination on perchlorate. 

Response: See response to comment code 6400. 

Commenter Name: Deborah Swackhamer 

Commenter Organization: Science Advisory Board 

EPA Document ID: EPA-HQ-OW-2008-0692-1749 

EPA Comment ID: 20659 

EPA Comment Code: 6400 

 

Comment: November 5, 2008 

The Honorable Stephen L. Johnson Administrator U.S. Environmental Protection Agency 1200 

Pennsylvania Avenue, N.W. Washington, D.C. 20460 

Dear Administrator Johnson: 

Thank you for your memorandum of October 20, 2008, requesting that the Science Advisory Board 

(SAB) undertake a study to provide advice on how EPA can strengthen scientific assessments, better 

communicate the results of assessments, and integrate natural science assessment with economic and 

social assessments to support EPA decision making. I had the opportunity to discuss the request 

with my colleagues this week at a public advisory meeting of the chartered SAB. We will undertake 

this effort with the goal of providing advice to the new EPA Administrator within a year. 

At our public meeting on October 28, 2008, the chartered SAB also discussed a draft report from 

the SAB's Drinking Water Committee on EPA's Draft Third Drinking Water Contaminant 

Candidate List (CCL3). The Committee’s draft report highlighted its recommendation that 

perchlorate is one of four chemicals that "should be a high priority for consideration by the Agency, 

because there is a higher degree of certainty about their toxicity, occurrence, and treatability." 

The SAB is also aware that EPA published a Drinking Water: Preliminary Regulatory Determination 

on Perchlorate in the Federal Register on October 10, 2008 (73 FR 60262-60282). That notice 

provides a preliminary determination that "a national primary drinking water regulation (NPDWR) 

for perchlorate would not present 'a meaningful opportunity for health risk reduction for persons 

served by public water systems'" and provides a thirty-day public comment period. The notice also 

states that EPA plans to issue a final regulatory determination by December 2008. It should be 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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noted that this preliminary determination relies on the use of a dosimetric model which is now 

undergoing letter peer review, and thus, its soundness will not be publicly vetted. 

Given perchlorate's wide occurrence and well-documented toxicity to humans, the SAB strongly 

believes that there must be a compelling scientific basis to support a determination not to regulate 

perchlorate as a national drinking water contaminant. The quality of the scientific foundation for 

EPA's decisions depends on peer review, which brings a variety of scientific perspectives to bear on 

critical components of EPA's decisions. Where science assessments have been conducted with the 

benefit of external scrutiny, the end products have been better able to support the policy making 

process. This view is very much aligned with the perspectives expressed in your memorandum to the 

SAB. 

Response: Administrator Stephen Johnson replied to the SAB on January 9, 2009. The letter is 

available in EPA’s docket ID No. EPA-HQ-OW-2009-0297 for this notice. which is located in 

docket EPA-HQ-OW-2008-0692. 

Commenter Name: Lynn Thorp 

Commenter Organization: Clean Water Action 

EPA Document ID: EPA-HQ-OW-2008-0692-2017 

EPA Comment ID: 20851 

EPA Comment Code: 6400 

 

Comment: We are particularly concerned that the preliminary determination was issued before peer 

reviews of the physiologically-based pharmacokinetics (PBPK) model used to derive the health 

reference level AND the health reference level itself were available. Given widely varying analysis of 

existing data, these peer reviews could shed important light on the Agency’s deliberations. We urge 

the Agency to reconsider its determination and to take the time necessary to fully consider setting a 

federal standard for perchlorate in drinking water. 

I appreciate the opportunity to weigh in on this important decision and am happy to provide more 

information if required. 

Sincerely, Lynn Thorp, National Campaigns Coordinator CC: Eric Burneson, OGWDW 

Response: See response to comment code 6400. 

Commenter Name: Caroline Baier-Anderson, PhD 

Commenter Organization: Environmental Defense Fund 

EPA Document ID: EPA-HQ-OW-2008-0692-1797 

EPA Comment ID: 20949 

EPA Comment Code: 6400 

 

Comment: The Post hoc Application of PD Modeling Inappropriately Allows the Exceedence of 

the RfD 

EPA has chosen to use a novel approach in setting a risk-based health risk level for perchlorate by 

using physiologically based pharmacokinetic modeling to justify the exceedence of the reference 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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dose at a level ranging from 2 - over 5%. In doing so, EPA would allow perchlorate exposures to 

attain unacceptably high levels. 

The model that EPA is using has not yet completed peer review, so that stakeholders have no 

assurance that the model design is appropriate for the task at hand. EPA should wait until the peer 

review process is complete before applying this model for official purposes as the peer review 

process could uncover important limitations of the model. For instance, while the model reports 

that predicted perchlorate blood levels would be higher in the fetus, lactating women and neonates, 

it is not clear if the model includes new information regarding the impact of TSH on NIS uptake of 

perchlorate (e.g., Tran et al. 2008 is not cited in the EPA document describing the model, 

EPA/600/R-08/106A), nor is it known how this new information might affect the modeling results. 

A peer review panel would be in the best position to weigh in on questions such as this one. 

It is also not clear if the model has been validated using responses of sensitive populations that 

include sub-optimal iodine intake. Given the documented impact on response to perchlorate 

exposure, this is would be an important step in the validation process. The model extrapolations 

were reportedly compared to data from the Chilean population, which as noted above, was fully 

iodine sufficient. Considering the demographics of iodine insufficiency in the US, it is imperative 

that the model extrapolations also be compared with data from a population that is not iodine 

sufficient. 

Response: See response to comment code 6400. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20998 

EPA Comment Code: 6400 

 

Comment: Despite these conclusions, only one week later and without waiting for the report to be 

peer-reviewed and available for public comment, EPA announced that it would not regulate 

perchlorate in drinking water. Although the Federal Register notice does report the staff 

conclusions, it contradicts them concluding that "EPA believes drinking water with perchlorate 

concentrations at or below the HRL of 15 ug/L is protective of all subpopulations."[FN52: Id. at 

60280] 

Response: EPA has decided to regulate perchlorate in drinking water. See response to comment 

code 6120 and response to comment code 6400. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 21004 

EPA Comment Code: 6400 

 

Comment: First, such a determination is premature, since the Agency is still awaiting peer review 

comments on the HRL and has only just received peer review comments on the PBPK model. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Response: See response to comment code 6400. 

 
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EPA Comment Code: 6500 Comments on alternative risk reduction approaches 

Individual Comments 

Commenter Name: Richard T. Kloos 

Commenter Organization: American Thyroid Association (ATA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0635 

EPA Comment ID: 28530 

EPA Comment Code: 6500 

 

Comment: We are writing on behalf of the American Thyroid Association (ATA) in response to 

your request for comments (Fed Reg 74:41883, 08/19/09) regarding EPA's perchlorate regulatory 

determination. The ATA represents the largest and most established group of physicians dedicated 

to the study of the thyroid gland and its disorders. 

Decreases in maternal thyroid hormone associated with even mild iodine deficiency may have 

adverse effects on the cognitive function of offspring.1,2,3 It has recently been suggested that mild 

iodine deficiency may also be associated with thyroid deficiency resulting in attention deficit and 

hyperactivity disorders in offspring.4 Iodine deficiency affects over 2.2 billion individuals worldwide 

(38% of the world’s population), and iodine deficiency is the leading cause of thyroid failure causing 

preventable mental retardation worldwide.5 

Over the last few decades, iodine intake in the United States has declined.6 Although iodine intake 

remains sufficient for the general U.S. population, there have been concerns in recent years that 

some pregnant women and women in their childbearing years may have inadequate iodine intake.7,8 

For this reason, in 2006 the ATA published recommendations for iodine supplementation of all U.S. 

pregnant and lactating women.9 These guidelines have not been widely adopted, and the availability 

and frequency of use of iodine-containing prenatal multivitamin supplements among pregnant U.S. 

women remains suboptimal.10,11 

Response: See response to comment ID 28842 under comment code 6500. 

As discussed in detail in the final regulatory determination, EPA has found that perchlorate may 

have an adverse effect on human health. 

 

Commenter Name: Richard T. Kloos 

Commenter Organization: American Thyroid Association (ATA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0635 

EPA Comment ID: 28532 

EPA Comment Code: 6500 

 

Comment: We would strongly urge that, whatever the EPA determines about the need for 

regulation of perchlorate in drinking water, attention should be paid to ensuring adequate iodine 

nutrition in the U.S., particularly among women who are pregnant or lactating. 

Thank you for this opportunity to comment upon and contribute to your regulatory determination 

for perchlorate. Clearly, there is more need for studies in this area in order to obtain greater clarity. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Sincerely, Richard T. Kloos, M.D. Secretary/Chief Operating Officer, American Thyroid 

Association Co-Director, The Ohio State University Thyroid Cancer Unit Divisions of 

Endocrinology and Nuclear Medicine Columbus, OH. 43210-1296 Richard.Kloos@OSUMC.edu 

Terry F. Davies, MB.BS, MD, FRCP, FACE President, American Thyroid Association Florence and 

Theodore Baumritter Professor of Medicine Mount Sinai School of Medicine One Gustave Levy 

Place, Box 1055 New York, NY 10029-6574 

References 

1 World Health Organization, United Nations Children’s Fund, and International Council for the 

Control of Iodine Deficiency Disorders. Assessment of iodine deficiency disorders and monitoring 

their elimination. A guide for programme managers, 3rd Edition. Geneva, Switzerland: World 

Health Organization, 2007. 2 Vermiglio F, Lo Presti VP, Castagna MG, Violi MA, Moleti M, 

Finocchiaro MD, Mattina F, Artemisia A, Trimarchi F. Increased risk of maternal thyroid failure 

with pregnancy progression in an iodine deficient area with major iodine deficiency disorders. 

Thyroid 1999;9:19-24. 3 Morreale de Escobar G, Obregon MJ, Escobar del Rey F. Iodine deficiency 

and brain development in the first half of pregnancy. Publ Health Nutr 2007;10:1554-70. 4 

Vermiglio ZF, Lo Presti VP, Moleti M, Sidoti M, Tortorella G, Scaffidi G, Castagna MG, Mattina F, 

Violi MA, Crisa A, Artemisia A, Trimarchi F. Attention deficit and hyperactivity disorders in the 

offspring of mothers exposed to mild- moderate iodine deficiency: A possible novel iodine 

deficiency disorder in developed countries. J Clin Endocrinol Metab 2004;89:60454-60. 5 

International Council for Control of Iodine Deficiency Disorders, www.iccidd.org 6 Hollowell JG, 

Staehling NW, Hannon WH, Flanders DW, Gunter EW, Maberly GF, Braverman LE, Pino S, Miller 

DT, Garbe PL, DeLozier DM, Jackson RJ. Iodine nutrition in the United States. Trends and public 

health implications: iodine excretion data from National Health and Nutrition Examination Surveys 

I and III (1971-1974 and 1988-1991). J Clin Endocrinol Metab 1998;83:3401-8. 7 Holowell JG, 

Haddow JE. The prevalence of iodine deficiency in women of reproductive age in the United States 

of America. Publ Health Nutr 2007;10:1532-9. 8 Pearce EN. U.S. iodine nutrition: where do we 

stand? Thyroid. 2008 Nov;18(11):1143-5. 9 Becker DV, Braverman LE, Delange F, Dunn JT, 

Franklyn JA, Hollowell JG, Lamm SH, Mitchell ML, Pearce E, Robbins J, Rovet J. Iodine 

Supplementation for Pregnancy and Lactation-United States and Canada: Recommendations of the 

American Thyroid Association. Thyroid 2006;16:949-51. 10 Leung AM, Pearce EN, Braverman LE. 

Iodine content of prenatal multivitamins in the United States. N Engl J Med 2009;360(9):939-40. 11 

Gregory CO, Serdula MK, Sullivan KM. Use of supplements with and without iodine in women of 

childbearing age in the United States. Thyroid. 2009;19(9):1019-20. 12 Blount BC, Pirkle JL, 

Osterloh JD, Valentin-Blasini L, Caldwell KL. Urinary perchlorate and thyroid hormone levels in 

adolescent and adult men and women living in the United States. Environmental Health 

Perspectives 2006;114:1865-71. 

Invited Editorial [see PDF docket ID EPA-HQ-OW-2009-0297-0635] 

Response: See response to comment ID 28530 under comment code 6500. 

Commenter Name: Stephen Haterius 

Commenter Organization: National Association of State Departments of Agriculture (NASDA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0664 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

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EPA Comment ID: 28549 

EPA Comment Code: 6500 

 

Comment: It is key to this discussion that exposure to perchlorate is only potentially problematic 

for individuals with iodine deficiency. There is no evidence[FN1: United States Food and Drug 

Administration. Perchlorate Questions and Answers. 

http://www.fda.gov/Food/FoodSafety/FoodContaminantsAdulteration/ 

ChemicalContaminants/Perchlorate/ucm077572.htm] that iodine deficiency is a widespread 

problem in the United States, and that only individuals who are on restrictive diets or purposely 

avoid iodine consumption are at risk for such a deficiency. While there is no evidence that iodine 

deficiency is a widespread problem in the US, women of child-bearing age and pregnant women are 

theoretically more at risk for effects of perchlorate consumption. Because inadequate iodine 

consumption during pregnancy can lead to negative birth outcomes, any further reduction uptake by 

the thyroid from exposure to perchlorate could pose a risk. While there is no evidence of widespread 

iodine deficiency in women of child-bearing age or pregnant women, this subpopulation could be 

targeted with education about diet during pregnancy and appropriate prenatal care that stresses the 

importance of adequate iodine consumption during pregnancy. 

In conclusion, we point to the EPA Office of Inspector General's (OIG) draft review[FN2: United 

States Environmental Protection Agency. Office Inspector General Scientific Analysis of 

Perchlorate. http://www.epa.gov/oig/reports/2009/20081230-2008-0010.pdf] of EPA's 

perchlorate assessment which emphasizes a number of important points that are relevant to this 

discussion. Specifically, the review points to the fact that other naturally occurring compounds 

found in food behave in a way that is similar to perchlorate. According to this review, regulating 

perchlorate in drinking water is unlikely to have any material impact on public health. We agree with 

the conclusion in OIG's draft that promoting adequate iodine intake is a superior approach than 

regulating perchlorate as a drinking water contaminant. 

Because the public health concerns associated with potential perchlorate consumption can be 

addressed through education and dietary modifications in a small subset of the population, NASDA 

is very concerned that EPA not adopt an approach that would lead to consumer confusion, food 

scares, and potential financial devastation for American agricultural producers. 

Sincerely, Stephen Haterius Executive Director 

Response: See response to comment ID 28530 under comment code 6500. Perchlorate 

contamination is more widespread in foods than in drinking water; however, EPA does not believe 

that the widespread presence of perchlorate in food overrides the need for public health risk 

reduction for persons served by PWSs with perchlorate contamination. The Agency presented an 

extensive evaluation of dietary exposure to perchlorate in the October 2008 and August 2009 

notices (73 FR 60262; USEPA 2008a and 74 FR 41883; USEPA 2009b). EPA has used this dietary 

exposure data to account for the relative source contribution (RSC) of perchlorate from food to 

estimate the range of levels of public health concern. EPA recognizes that a drinking water 

regulation would not eliminate total perchlorate exposure, but believes that the reduction in 

perchlorate exposure in drinking water presents a meaningful opportunity for health risk reduction 

for persons served by PWSs contaminated by perchlorate. EPA agrees that promoting iodide 

nutrition is good public health policy and may have a positive influence in reducing the iodide 

uptake inhibition effects associated with exposure to perchlorate. However, the Agency does not 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

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think it is appropriate to rely on the promotion of iodide nutrition in this case, especially since these 

activities are outside of EPA’s SDWA authority. As a result, while the health concerns associated 

with perchlorate may be addressed through other means, it is the Administrator’s judgment that a 

standard limiting perchlorate in drinking water can reduce health risk, particularly to fetuses, infants 

and children. 

Regarding the OIG report, while EPA acknowledges that nitrate and thiocyanate have the same 

mode of action as perchlorate, and that the effects of combined exposure to perchlorate, nitrate, and 

thiocyanate are additive, EPA does not believe there are sufficient scientific data currently available 

to assess and characterize the combined risk of these contaminants. EPA has committed to a 

drinking water strategy that outlines four principles to expand public health protection for drinking 

water (USEPA, 2010b). One of these principles is to address contaminants as groups. However, 

EPA does not believe that regulatory action to address perchlorate should be further delayed. 

Therefore, EPA intends to develop a proposed rule for perchlorate. At such time as a NPDWR is 

promulgated, EPA is required to review and revise, as appropriate, its drinking water standards at 

least every six years. Any revision must at least maintain or improve public health protection. When 

there are sufficient scientific data to assess the cumulative risks of perchlorate and other 

contaminants, EPA will review this information to evaluate whether any revisions of NPDWRs are 

appropriate. 

EPA has determined the need to regulate perchlorate in drinking water. Care will be taken to 

communicate the implications of that regulation. 

Commenter Name: John P Gibbs 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0636 

EPA Comment ID: 28555 

EPA Comment Code: 6500 

 

Comment: Efforts to assure adequate iodine in prenatal vitamins and infant formulas as suggested 

by the draft OIG report offer the most reasonable and immediate protection from the presence of 

NIS inhibitors among the recognized sensitive subpopulations. 

REFERENCES 

Pearce EN, Spencer CA, Mestman J, Lee R, Bergoglio LM, Mereshian P, He X, Leung AM, 

Braverman LE, 2008. Thyroid Function is Not Affected by Environmental Perchlorate Exposure in 

First Trimester Pregnant Women from California and Argentina. Presentation at Annual Meeting of 

the Endocrine Society, San Francisco, CA, June 15-18, 2008. 

Pearce EN, Lazarus JH, Smyth PPA, He X, Dall'Amico D, Parkes AB, Burns R, Smith DF, Maina 

A, Leung AM, Braverman LE, 2007. Thyroid function is not affected by environmental perchlorate 

exposure in first trimester pregnant women. Thyroid 17 (s1), S-133 

Lamm, S.H., Hollowell, J.G., Engel, A., Chen, R., 2007. Perchlorate, thyroxine, and low urine iodine 

association not seen with low creatinine-adjusted urine iodine among women of childbearing age. 

Thyroid 17 (s1), S-51. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Tonacchera M, Pinchera A, Dimida A, Ferrarini E, Agretti P, Vitti P, Santini F, Crump K, Gibbs 

J.Relative potencies and additivity of perchlorate, thiocyanate, nitrate, and iodide on the inhibition of 

radioactive iodide uptake by the human sodium iodide symporter. Thyroid. 2004 Dec;14(12):1012-9. 

Braverman LE, He X, Pino S, Cross M, Magnani B, Lamm SH, Kruse MB, Engel A, Crump KS, 

Gibbs JP. The effect of perchlorate, thiocyanate, and nitrate on thyroid function in workers exposed 

to perchlorate long-term. J Clin Endocrinol Metab. 2005 Feb;90(2):700-6.. 

Crump KS, Gibbs JP. Benchmark calculations for perchlorate from three human cohorts. Environ 

Health Perspect. 2005 Aug;113(8):1001-8. 

Tellez Tellez R, Michaud Chacon P, Reyes Abarca C, Blount BC, Van Landingham CB, Crump KS, 

Gibbs JP. Long-term environmental exposure to perchlorate through drinking water and thyroid 

function during pregnancy and the neonatal period. Thyroid. 2005 Sep;15 

Gibbs JP. A Comparative Toxicological Assessment of Perchlorate and Thiocyanate Based on 

Competitive Inhibition of Iodide Uptake as the Common Mode of Action. Human & Ecological 

Risk Assess. 2006 Feb 12:157-173 

Gibbs JP, Van Landingham CB. Urinary perchlorate excretion does not predict thyroid function 

among pregnant women. Thyroid 2008 Jul;18(7):807-8. 

Lamm SH, Braverman LE, Li FX, Richman K, Pino S, Howearth G. Thyroid health status of 

ammonium perchlorate workers: a cross-sectional occupational health study.J Occup Environ Med. 

1999 Apr;41(4):248-60. 

Amitai Y, Winston G, Sack J, Wasser J, Lewis M, Blount BC, Valentin-Blasini L, Fisher N, Israeli A, 

Leventhal A. Gestational exposure to high perchlorate concentrations in drinking water and 

neonatal thyroxine levels. Thyroid. 2007 Sep;17(9):843-50 

Response: See response to comment ID 28530 under comment code 6500. 

Commenter Name: Sonia Salas 

Commenter Organization: Western Growers Association on behalf of several California 

agriculture groups 

EPA Document ID: EPA-HQ-OW-2009-0297-0652 

EPA Comment ID: 28681 

EPA Comment Code: 6500 

 

Comment: For iodine, FDA found that each of the 14 age/sex groups, including infants, children, 

and women of childbearing age exceeded the average intake levels estimated by the NAS to meet 

requirements for healthy individuals. 

In light of these findings, FDA continues to stand by its prior recommendation that consumers 

should not alter their infants' and children's diets or eating habits. Indeed, many of the foods at issue 

are major dietary sources of iodine and other nutritionally essential substances. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA's Calculation of the Relative Source Contribution for its 2008 Preliminary Regulatory 

Determination also Reveals that Perchlorate Exposure from Food is Below any Meaningful Level of 

Concern. 

Response: EPA calculated potential alternative HRLs that were included in the August 2009 notice. 

These values incorporate and estimate perchlorate from food, deriving the potential alternative HRL 

such that only the water contribution of perchlorate would require adjustment to attain a tolerable 

perchlorate exposure from all sources. The Agency presented an extensive evaluation of dietary 

exposure to perchlorate in the October 2008 and August 2009 notices (73 FR 60262; USEPA 2008a 

and 74 FR 41883; USEPA 2009b). EPA has used this dietary exposure data to account for the 

relative source contribution (RSC) of perchlorate from food to estimate the range of levels of public 

health concern. EPA recognizes that a drinking water regulation would not eliminate total 

perchlorate exposure, but believes that the reduction in perchlorate exposure in drinking water 

presents a meaningful opportunity for health risk reduction for persons served by PWSs 

contaminated by perchlorate. 

Commenter Name: Tom Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0415 

EPA Comment ID: 28842 

EPA Comment Code: 6500 

 

Comment: AWWA also concurs with the Agency's Inspector General [FN1: Wilson, M. 2008. 

Scientific Analysis of Perchlorate. US Environmental Protection Agency, Office of Inspector 

General. Available at http://www.epa.gov/oigearth/reports/2009/20081230-2008-0010.pdf] in 

stating that regulatory action under the Safe Drinking Water Act (SDWA) is not the appropriate or 

effective way to address the overarching public health issue - iodide deficiency. The National 

Research Council (NRC) assessment [FN2: National Research Council (NRC). 2005. Health 

Implications of Perchlorate Ingestion. National Academy Press, Washington, DC.] of perchlorate 

also recognized iodide deficiency as the larger public health issue. 

Response: EPA based its final regulatory determination on a number of different factors including 

the careful consideration of public comments. Regarding correcting iodine deficiencies, the Food 

and Drug Administration and Centers for Disease Control generally conclude that there is sufficient 

iodine in the diet. Below are findings from FDA’s Total Diet Study (2003-2004) that estimates the 

dietary intake of iodide for 14 age-sex groups (Murray et al., 2008) and CDC’s National Health and 

Nutrition Examination Survey that measured perchlorate in the urine of study participants in (2003-

2004, no data on < age 6). FDA’s Total Diet Study findings: - Infants, 6-11 months, exceeded their 

Adequate Intake - Children and adult age/sex groups exceed their relevant Estimated Average 

Requirement CDC’s National Health and Nutrition Examination Survey: - "This finding confirms 

the stability of the U.S. iodine intake and continued adequate iodine nutrition for the country in 

general." - "On the basis of median urinary iodine concentrations, iodine intake of women of 

childbearing age appears adequate." 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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EPA Comment Code: 7000 Miscellaneous Comments 

Response to Code 7000: See response to comment code 6120 for a discussion of EPA’s decision 

to regulate perchlorate in drinking water and initiate the development of a proposed national 

primary drinking water regulation. EPA received a number of comments in response to its 

preliminary regulatory determination for perchlorate(73 FR 60262, October 10, 2008) and the 

supplemental request for comment on the perchlorate regulatory determination (74 FR 41883, 

August 19, 2009) that were not directly related to the Agency’s decision to regulate perchlorate in 

drinking water. These comments are compiled in response to comment code 7000 in this response 

to comment document. EPA is not directly addressing comments that do not relate to the Agency’s 

decision on whether or not the Agency should promulgate a national primary drinking water 

regulation (NPDWR) for perchlorate under the Safe Drinking Water Act (SDWA). SDWA provides 

EPA with the authority to regulate public water systems through national primary drinking water 

regulations. Under this authority EPA plans to propose and promulgate a regulation that public 

water systems will have to comply with through monitoring and potentially using treatment 

techniques to reduce the levels of perchlorate in the drinking water they supply to their customers. 

The authority under SDWA does not apply to discharges, improper disposal or other releases of 

perchlorate or other contaminants. EPA therefore is not addressing comments related to these 

concerns under this action. EPA is also not addressing comments related to contaminants other 

than perchlorate or drinking water policies unrelated to the perchlorate regulatory determination. 

Individual Comments 

Commenter Name: W Zielke 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0332 

EPA Comment ID: 19818 

EPA Comment Code: 7000 

 

Comment: We should be finding out how Perchlorates are getting into our water and take steps to 

prevent that from happening. 

Response: See response to comment code 7000. 

Commenter Name: Margaret Baco 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0624 

EPA Comment ID: 19978 

EPA Comment Code: 7000 

 

Comment: Further, there is an urgent requirement to safeguard public health through effective legal 

action requiring the provision of reliable tap water filters in all public establishments, inclusive of tax 

relief measures. All public schools, hospitals and restaurants should be equipped with this safeguard 

immediately to reduce the risk of further exposure. 

Further, new programs must be established to ensure that private homes are able to afford 

installation of effective water filters. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1064 of 1099

Further, legal actions must be established to regulate and control the collection of appropriate 

disposal of such filters. 

Sincerely, 

Margaret Baco 

Response: See response to comment code 7000. NSF International, the Water Quality Association 

and other independent certification organizations have certified household treatment systems for 

perchlorate removal. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0839 

EPA Comment ID: 20108 

EPA Comment Code: 7000 

 

Comment: PEACELOVE EARTHHEART 

Response: This is not a comment, a response is not necessary. 

Commenter Name: L. L. Schumacher 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-0664 

EPA Comment ID: 20239 

EPA Comment Code: 7000 

 

Comment: And what about the highly toxic fumigant you approved for use on strawberries exactly 

1 year ago, for one year. Are you going to make that permanent? I would venture to say yes because 

the "money grubbers" want it and you always rule in their favor. 

You should change your name from the Environmental Protection Agency, to the Environmental 

Destruction Agency. 

Yours truly, Leonard L. Schumacher 

Response: See response to comment code 7000. 

Commenter Name: Ed Thomas 

Commenter Organization: National Rural Water Association 

EPA Document ID: EPA-HQ-OW-2008-0692-1669 

EPA Comment ID: 20621 

EPA Comment Code: 7000 

 

Comment: In closing we find it inexplicable that the Agency was able to interpret the statutory 

standard of what determines the "meaningful opportunity for health risk reduction" and make a 

determination in a relative short period of time. But, on the other hand, the Agency has not been 

able to interpret nor make a determination on similar statuary standards of "unreasonable risk to 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1065 of 1099

health" (URTH) [42USC300g-5(a)(3)] or "protective of public" [42USC300g-1(b)(15)(B)]. What we 

find inexplicable is that the determination EPA has failed to make heretofore is more pressing to 

community water supplies than the determination EPA recently made for perchlorate. We believe 

that EPA should identify the URTH levels and what constitutes "protective of public health". 

We thank you for the opportunity to provide comments regarding this important matter. 

Sincerely, 

Ed Thomas 

Electronic Attachments: 1. Rubin trade off health risk final.pdf 

Response: See response to comment code 7000. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-1748 

EPA Comment ID: 20658 

EPA Comment Code: 7000 

 

Comment: Finally, if the SAB convenes any public meeting on perchlorate, the PSG would 

welcome an opportunity to present the scientific literature and our public comments. For over 10 

years, the PSG has worked cooperatively with EPA, states, and other Federal agencies to provide the 

best available scientific information on perchlorate to assist public agencies. We look forward to any 

such opportunity with the SAB. 

Sincerely, 

Mr. Michael Girard Chairman Perchlorate Study Group 

Cc: Marcus Peacock, Deputy Administrator Benjamin Grumbles, Assistant Administrator, Office of 

Water Cynthia Dougherty, Director Office of Ground Water and Drinking Water Eric Burneson, 

Chief, Targeting and Analysis Branch Suhair Shallal, SAB Designated Federal Officer 

Response: There will be future opportunities to provide input/submit comments during 

development of a proposed NPDWR for perchlorate. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1743 

EPA Comment ID: 20685 

EPA Comment Code: 7000 

 

Comment: The perchlorate contamination in Tewksbury, MA a few years ago resulted in 75% of 

my household not being able to consume our municipally provided tap water. My two children 

(both under age 2) and my pregnant wife were in the 'high risk' group that were advised not to 

consume or brush their teeth with the contaminated water. Standard commercially available water 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1066 of 1099

filtration systems were either a) incapable of addressing the contaminant or b) unable to remove 

perchlorate contaminants to any particular standardized safe level. The filtration systems reviewed 

included systems that used reverse osmosis filtration as their buy-in into the organization. 

Response: See response to comment code 6120. NSF International, the Water Quality Association 

and other independent certification organizations have certified household treatment systems for 

perchlorate removal. 

Commenter Name: Y. Carbajal 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1847 

EPA Comment ID: 20736 

EPA Comment Code: 7000 

 

Comment: It is in everyone's best interest that drink water be tested for containments. Failure to do 

so can lead to a catastrophic epidemic. 

Response: See comment code 7000. 

Commenter Name: R. Howard 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1848 

EPA Comment ID: 20737 

EPA Comment Code: 7000 

 

Comment: UR KILLING US THANK FOR THE WONDERFUL 8YRS MR.PRES IHOPE UR 

LIFE ISNT AS LONG AS THESE 8YRS HAVE BEEN 

Response: This is not a comment, a response is not necessary. 

Commenter Name: J Bennet 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-1860 

EPA Comment ID: 20744 

EPA Comment Code: 7000 

 

Comment: 11/06/08 

Dear EPA, 

Please get toxins out of our water. 

J. Bennet 211 Royal St. Alexandria, VA 22314 

Response: See response to comment code 7000. 

Commenter Name: 

Commenter Organization: The Night Move, LLC 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1067 of 1099

EPA Document ID: EPA-HQ-OW-2008-0692-1960 

EPA Comment ID: 20808 

EPA Comment Code: 7000 

 

Comment: As a new business in Michigan, we have taken the initiative to show concern for the 

environment in every way we can. We collectively look for ways to reduce our negative impact on 

the environment and search for ways to improve it. The Night Move started on the premise to get 

people out of their cars and into public transportation, reducing the air pollution from car exhaust. 

Also, we run our bus on biodiesel to reduce our emissions. For the emissions we do put out, we 

have partnered with CarbonFund.org to neutralize our carbon footprint. We don't stop there. Our 

flyers and advertisements are printed on recycled paper, passenger trash is recycled, and we reuse 

water to clean the bus. Of course, there are always ways to improve and we are always looking for 

them. We do this because we know what we do has an impact on the environment around us. This 

means we are impacting the people around us whether they use our services or not. We like to do 

our part to keep our environment clean and safe to live in, and we expect others to be just as 

courteous, especially our government. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2007 

EPA Comment ID: 20837 

EPA Comment Code: 7000 

 

Comment: DIRTY LAKES!! Don't do this!!! 

CLEAN LAKES!! 

Keep our Lakes Clean!!! 

[See illustration in PDF EPA-HQ-OW-2008-0692-2007] 

Response: See response to comment code 7000. 

Commenter Name: Brien Beebe 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2011 

EPA Comment ID: 20843 

EPA Comment Code: 7000 

 

Comment: 11/6/08 

I WOULD LIKE TO BELIEVE THAT THE EPA WOULD FIGHT TO PROTECT FOR 

CLEAN WATER AND "PROTECT OUR ENVIRONMENT." 

BRIEN BEEBE 311 DUKE ST. ALEXANDRIA VA. 22314 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1068 of 1099

Response: See response to comment code 7000. 

Commenter Name: B.K. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2012 

EPA Comment ID: 20844 

EPA Comment Code: 7000 

 

Comment: 11/06/08 

Dear EPA, 

Toxins out of water. 

BK 207 S. Royal Alexandria, VA 22134 

Response: See response to comment code 7000. 

Commenter Name: Lynn Thorp 

Commenter Organization: Clean Water Action 

EPA Document ID: EPA-HQ-OW-2008-0692-2017 

EPA Comment ID: 20849 

EPA Comment Code: 7000 

 

Comment: December 1, 2008 

Stephen L. Johnson Administrator U.S. Environmental Protection Agency Washington DC 20460 

Dear Administrator Johnson, 

I am writing on behalf of Clean Water Action and it's 1.2 million members. Due to clerical errors, 

our organization's signature was not affixed to comments on the Agency's preliminary determination 

on perchlorate which were prepared and submitted by the Natural Resources Defense Council for 

the relevant docket. I want to draw your attention to our organization's support for these comments 

despite our signature not being on the official docket copy. 

Response: The commenter's support for comments prepared by the Natural Resources Defense 

Council (comment letter ID EPA-HQ-OW-2008-0692-1988) is noted. 

Commenter Name: Lenny Siegel 

Commenter Organization: Center for Public Environmental Oversight 

EPA Document ID: EPA-HQ-OW-2008-0692-2019 

EPA Comment ID: 20855 

EPA Comment Code: 7000 

 

Comment: This reminds me of O.J. Simpson’s criminal defense. He insisted that some third party 

or parties killed his wife and Ronald Goldman, but he showed little interest in finding the unknown 

perpetrators. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1069 of 1099

Response: No response necessary to the information provided by the commenter. 

Commenter Name: Ron Curry 

Commenter Organization: New Mexico Environment Department 

EPA Document ID: EPA-HQ-OW-2008-0692-1796 

EPA Comment ID: 20934 

EPA Comment Code: 7000 

 

Comment: In considering these comments, particularly this groundwater monitoring data, it is 

important for EPA to understand that New Mexico is very dependent on its groundwater resources 

for drinking water. New Mexico is an arid state, with relatively little surface water. New Mexicans 

obtain approximately 90 percent of their drinking water from groundwater aquifers.[FN11: Affidavit 

of William Olsen, Chief, Ground Water Quality Bureau, N.M. Environment Dep't, at 3, In re 

Appeal of Supplemental Discharge Permit for Closure (DP-1341) for Phelps Dodge Tyrone, Inc. 

(N.M. Water Quality Control Comm'n July 9, 2007) (Nos. WQCC 03-12(A) and WQCC 03-13(A)).] 

And New Mexico is growing and developing rapidly, placing greater demands on its aquifers. 

According to the New Mexico State Demographer at the University of New Mexico Bureau of 

Business and Economic Research, the population of New Mexico is expected to increase by 30 

percent between 2005 and 2020, and by more than 50 percent between 2005 and 2035.[FN12: 

University of New Mexico, Bureau of Business and Economic Research, Population Projections for 

New Mexico and Counties, available at www.unm.edu/~bber. The information was confirmed in a 

telephone conversation with Adelamar N. Alcantera, Ph.D., New Mexico State Demographer, on 

November 24, 2008.] We therefore assume that much of the State's groundwater will be used for 

drinking water in the future. Consequently, there is a substantial likelihood that this perchlorate 

contamination will occur in public water systems in the foreseeable future. 

Response: See response to comment code 7000. 

Commenter Name: Herwig Opdebeeck 

Commenter Organization: Opdebeeck Consulting 

EPA Document ID: EPA-HQ-OW-2008-0692-1798 

EPA Comment ID: 20955 

EPA Comment Code: 7000 

 

Comment: RE: Docket ID No. EPA-HQ-OW-2008-0068 

Comments on the US Environmental Protection Agencyâ€TMs Preliminary Regulatory 

Determination on Perchlorate November 28th, 2008 

Comment on the USEPA Office of Waterâ€TMs Preliminary Regulatory Determination on 

Perchlorate. 

Comment subjects 

1. Relative Source Contribution (RSC) EPAâ€TMs past RSC based on a "default" assumption versus 

EPAâ€TMs RSC used in this Preliminary Regulatory Determination 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1070 of 1099

2. The very particular case of perchlorate: Total effective equivalent perchlorate NOEL and RfD 

3. Checking of some outcomes of this EPA preliminary determination with those obtained trough 

another road. 

Response: This is not a comment, a response is not necessary. 

Commenter Name: Jennifer Sass, PhD. 

Commenter Organization: Natural Resources Defense Council 

EPA Document ID: EPA-HQ-OW-2008-0692-1988 

EPA Comment ID: 20996 

EPA Comment Code: 7000 

 

Comment: E. A final MCL below 1 ppb is both technologically and economically feasible. 

Technical Feasibility 

U.S. EPA's Method 314 approved ion chromatography detection protocol, for example, routinely 

detects perchlorate pollution at levels of 0.2ppb and the State of Massachusetts has established a 

‘reportable concentrations level for perchlorate of 2 ppb.[FN46: Thorne, Philip G. Field Screening 

Method for Perchlorate in Water and Soil, ERDC/CRREL Technical Report 04-8, 36 pp, Apr 

2004.],[FN47: "Final Changes to the Massachusetts Contingency Plan -310 CMR 40.0000," 

downloaded from http://www.mass.gov/dep/cleanup/laws/perchlorate-310CMR40-07282006.pdf, 

November 2 2006.] Ion exchange technology is able to treat perchlorate contamination to levels 

considerably below 1 ppb. Treatment systems operating on perchlorate- impacted wells owned by 

Aquarion Water Company in Massachusetts, for example, treat wells to below 1 ppb.[FN48: "US 

Filter Recovery Services," downloaded from www.usfilter.com, November 2 2006.] 

Economic Feasibility 

The cost of complying with a perchlorate Maximum Contaminant Level of less than 1 ppb for the 

City of Rialto - one of the most impacted water systems in California - for example will be zero after 

cleanup costs are recovered from identified responsible parties. A complete economic feasibility 

study should also include an analysis of the costs associated with healthcare and lost work resulting 

from illnesses associated with perchlorate contaminated water. 

Response: See response to comment code 6120. Feasibility and health risk reduction and cost 

analyses will be performed in support of a proposed National Primary Drinking Water standard. 

Commenter Name: Michael Girard 

Commenter Organization: Perchlorate Study Group 

EPA Document ID: EPA-HQ-OW-2008-0692-2082 

EPA Comment ID: 21025 

EPA Comment Code: 7000 

 

Comment: Your letter also highlights states which have issued MCLs, including California, 

Massachusetts, and New Jersey (which has proposed, but not finalized a standard.) 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1071 of 1099

As your letter points out, several states have issued standards or taken other regulatory steps relating 

to perchlorate in drinking water.. That is a separate issue from whether a national standard is 

advisable. 

The Association of State Drinking Water Administrators noted in their recently filed comments that 

"States are generally in favor of EPA’s decision not to regulate, but there are some states that do 

favor a national regulation on perchlorate, especially those who have already set their own 

standard."[FN7: Association of State Drinking Water Administrators, Letter to EPA Docket, 

Docket EPA-HQ-OW-2008-0692, Nov. 10, 2008.] The American Water Works Association, the 

largest organization of water supply professionals in the world, announced its agreement with EPA’s 

preliminary determination, based upon the results of two independently commissioned assessments 

which support EPA decision. [FN8: American Water Works Association, Drinking Water: 

Preliminary Regulatory Determination on Perchlorate Docket EPA-HQ-OW-2008-0692; Nov. 10, 

2008.] 

Response: See response to comment code 7000. 

Commenter Name: Teresa Jordan 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2086 

EPA Comment ID: 21108 

EPA Comment Code: 7000 

 

Comment: Mr. Grumbles and Mr. Burneson, it is imperative that the USEPA, in Federal Register 

notices and in the Agency's Website, provide a facsimile number for the interested persons to 

submit written comments. I do not E-mail. I do not always have transportation to get to the post 

office. Foot problems keep me from walking long distances. Since I have a fax machine, I am able to 

submit comments not only to members of Congress, but State and Federal government elected 

officials, and agenices. All public comment submittal tools must be made available. The USEPA by 

doing otherwise limits the public's right to comment on issues. 

Mr. Grumbles and Mr. Burneson, I notice that the USEPA provides an avenue to help the hearing 

impaired population participate. How does the USEPA help the visually impaired population 

participate in the public comment process? 

Response: EPA acknowledges the commenter's request. In the future, written comments may be 

submitted to EPA's Docket Center Public Reading Room at the following fax number: 202-566-

9744. Please include the appropriate Docket ID No. with your submission. 

Commenter Name: Philip Hoos 

Commenter Organization: Earthjustice 

EPA Document ID: EPA-HQ-OW-2008-0692-2111 

EPA Comment ID: 21137 

EPA Comment Code: 7000 

 

Comment: To whom it may concern, 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1072 of 1099

I would like the attached document to be posted in docket number EPA-HQ- OW-2008-0692. 

Please disregard my previous email where I provide the incorrect docket number. If you have any 

questions please feel free to email me. 

Thank you for your time, Phil 

 Phillip Hoos Research Associate Earthjustice 426 17TH St., 5th Floor Oakland, CA 94612 T: 510-

550-6700 F: 510-550-6740 www.earthjustice.org 

Because the earth needs a good lawyer 

[please see attachment PDF Docket ID EPA-HQ-OW-2008-0692-2111] 

Response: The attachment has been posted to docket number EPA-HQ- OW-2008-0692. 

Commenter Name: Charlotte L. Sherry 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2119 

EPA Comment ID: 21989 

EPA Comment Code: 7000 

 

Comment: Water Docket, EPA Mailcode 2822T 1200 Pennsylvania Ave., Washington, D.C. 20460 

We have lived in Gambrills area since 1969. Lately when I make coffee, hot tea, ice tea or something 

similar it has an odor and taste of chorine in it. 

The water line has broken twice in the same place in the last few years. All these pipes have to be old 

and need to be checked for cracks that let contamination into our water. 

Thank you, Charlotte L. Sherry 

Response: See response to comment code 7000. 

Commenter Name: David L. Louden 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2161 

EPA Comment ID: 22091 

EPA Comment Code: 7000 

 

Comment: 21 November 2008 

STATEMENT FOR THE RECORD 

Subj: CLEAN WATER ACTION I CO DOCKET ID NO. EPA-HQ-OW-2008-0692 

Dear Sir/Madame; 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1073 of 1099

I wish it to be known that I support the testing, both routine and sustained, of water delivered by 

public, state or county for purposes of drinking, cooking, cleaning, bathing or their kind. 

The Environmental Protection Agency operates as a public trust on behalf of the citizens of the 

United States. It is therefore both a custodial responsibility as well as a matter of good stewardship 

to perform all due diligence in the execution of the duties and responsibilities assigned to the EPA 

by the laws and directives of the United States. I wish you continued success as you carry out this 

mandate on behalf of your fellow citizens. 

Kind regards, David L. Louden 7894 Bastille Pl Severn, MD 21144 410 551 7866 

davidlouden@hotmail.com 

Response: See response to comment code 6120. 

Commenter Name: John A. Forbes 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2162 

EPA Comment ID: 22092 

EPA Comment Code: 7000 

 

Comment: November 18, 2008 

Dear EPA Administrator Stephen Johnson 

I write to your with an urgent request to regulate greenhouse gas emissions under the Clean Air Act. 

Greenhouse gases are a serious threat to public health and people's welfare especially small children. 

The US must again take the lead on the issue at the Federal level. 

The Supreme Court affirmed to EPA authority. I urge you to regulate by setting specific emission 

reduction standards for power plants, big factories, vehicles and fuels. 

Please act John A Forbes III 

Response: See response to comment code 7000. 

Commenter Name: Thomas S Soell 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2184 

EPA Comment ID: 22378 

EPA Comment Code: 7000 

 

Comment: 13 Nov 2008 

To whom it may concern, 

I fortunately live next to the Herald Harbor water tower in Crownsville, Maryland. Every year we get 

a report on the level of contaminants found in the drinking water supplied by this source. It would 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1074 of 1099

be interesting to at least know the level of perchlorates in the water. I have no idea how to test for 

perchlorates or what level is safe or not. If they are harmful, it would be nice to know what levels 

they are in our water. 

Thanks for your attention to this matter! 

Thomas S. Soell 485 Mountain Rd Crownsville, MD 21032 

Response: See response to comment code 6120. You may want to call your drinking water utility or 

state drinking water program to learn the results of past monitoring or to find out if monitoring is 

required in your state. If there is no requirement for monitoring in your state, you can have your 

water analyzed by a laboratory that is certified for the analysis of perchlorate or similar compounds. 

An EPA website provides a list of state certification officers or links to certified laboratories in your 

state. 

Commenter Name: Sean Auth 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2212 

EPA Comment ID: 22414 

EPA Comment Code: 7000 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

As an idealistic youth, I like to believe that those who are in charge hold the interests of those it is 

their duty to protect above those of big business, in the face of the apathetic and corrupt. We 

already have to worry about enough epidemics affecting the women and children of this nation, 

please do your part to shorten the list, if not for my family then for yours. 

Sincerely, Sean Auth 619 Bates College Lewiston, ME 04240 

Response: See response to comment code 6120. 

Commenter Name: Hal Hyman 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2280 

EPA Comment ID: 22487 

EPA Comment Code: 7000 

 

Comment: Docket # EPA-HQ-OW-2008-0692 Environmental Protection Agency Mailcode: 

2822T, 1200 Pennsylvania Ave., NW Washington, 20460 

Dear Administrator Johnson and EPA staff, 

The NRDC is a radical group who are for the destruction of the United States disguised as 

environmentalism. It is Marxism. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1075 of 1099

BE AWARE AND DESTROY THEIR AGENDA 

Sincerely, Hal Hyman 49 Price Avenue Erlanger, KY 41018 

Response: This comment is not relevant to this action. 

Commenter Name: Under 13 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2085 

EPA Comment ID: 24975 

EPA Comment Code: 7000 

 

Comment: Dear Water people, 

I like clean water because we drink it. I would not like to drink dirty water. People in Africa have 

dirty water and are dying and they are not very happy. 

Love, [comment from patron under the age of 13] 

Response: See response to comment code 7000. 

Commenter Name: Kraig Erickson 

Commenter Organization: RMC Water and Environment (RMC) 

EPA Document ID: EPA-HQ-OW-2008-0692-2299 

EPA Comment ID: 24980 

EPA Comment Code: 7000 

 

Comment: Currently my company, RMC, is working with Pasadena Department of Water and 

Power to address high percholate levels in the Monk Hill area. Windsor Reservoir is a potable water 

storage reservoir constructed in the early 1900s with a capacity of 4.75 million gallons. It went out of 

service due to high percholate levels in the groundwater from wells feeding the Reservoir. PWP is 

currently constructing a percholate treatment facility at Reservoir site. Please feel free to contact me 

if you would like more information regarding PWP's actions to address percholate plumes. 

Kind regards, - Kraig Erickson Project Engineer RMC Water and Environment 2400 Broadway, 

Suite 300 Santa Monica, CA 90404 Phone: 310-566-6460 Fax: 310-566-6461 

KErickson@rmcwater.com http://ww.rmcwater.com Innovative Solutions for Water and the 

Environment 

Sincerely, Kraig Erickson 2400 Broadway Suite 300 Santa Monica, CA 90404 

Response: See response to comment code 7000. 

Commenter Name: Under 13 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2008-0692-2337 

EPA Comment ID: 25017 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1076 of 1099

EPA Comment Code: 7000 

 

Comment: Dear E.P.A, 

I want clean drinking water! 

From, [comment from patron under the age of 13] 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0073 

EPA Comment ID: 28350 

EPA Comment Code: 7000 

 

Comment: ARE YOU KIDDING????????THIS IS A NO BRAINER! DON'T WE HAVE 

ENOUGH AUTO IMMUNE DISEASES AND CANCER CAUSING SUBSTANCES IN OUR 

LIVES? ISN'T THE WORD 'PROTECTION' IN THE ENVIRONMENTAL PROTECTION 

AGENCY THE CLUE THAT YOUR AGENCY IS SUPPOSED TO PROTECT US FROM 

ANY CONTAMINANTS??? PLEASE WAKE UP NOW!!!!! 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0090 

EPA Comment ID: 28353 

EPA Comment Code: 7000 

 

Comment: PLEASE CONSIDER YOUR CHILDREN,GRANDCHILDREN, AND GREATGRAND CHILDREN WHEN TALKING ABOUT THIS CONTAMINATION OF 

OUR/THEIR DRINKING WATER. IT SHOULD BE SO ELEMENTARY OF A DECISION 

NOT TO ALLOW THE CONTAMINATION OF DRINKING WATER REGARDLESS OF 

MONETARY OR POLITICAL INFLUENCES. DO WHAT IS MORALLY JUST. PROTECT 

THE NATURAL RESOURCE WE WERE ENTRUSTED WITH;DON'T CONTAMINATE IT 

AND HOPE IT WILL BE SATISFACTORY. 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0118 

EPA Comment ID: 28358 

EPA Comment Code: 7000 

 

Comment: This has got to be a joke right? Plain and simple...would the EPA be drinking 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1077 of 1099

Response: See response to comment code 7000. 

Commenter Name: J. Clarke 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0125 

EPA Comment ID: 28361 

EPA Comment Code: 7000 

 

Comment: this really seems like a no brainer. we need to start acting on simple things like this in 

order to protect our future. with the onset of droughts throughout the US, we need to begin 

protecting what we do have before it's too late. 

thanks,j. clarke 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0134 

EPA Comment ID: 28363 

EPA Comment Code: 7000 

 

Comment: Please keep our waters safe! 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0157 

EPA Comment ID: 28373 

EPA Comment Code: 7000 

 

Comment: This is really angering me, I may not be 18 yet and a legal adult, but i have as much right 

as any to drink UNCONTAMINATED water! this isnt the only problem too with drinking water! It 

has recently been recognized as of sept. 12th (today actually) in the new york times how all across 

the nation people can't even drink their tap water because there are contaminants from coal 

companies in them. The water has been found to contain barium, arsenic, lead, magenese, and other 

harmful chemicals. People get ugly and painful rashes just by letting it touch their skin and have to 

apply a special lotion after showing because it makes their skin BURN. A 6 year old boy was 

brought to the dentist and had to get metal caps on his teeth because the water had eaten away the 

enamel from his molars! 

Government needs to address this because it is a fundamental living need- water. if we could ensure 

safely in our tap water, we could stop spending 10 billion dollars a year BOTTLING the stuff and 

just have people use a reusable safe stainless steel or hard safe-plastic bottle and save our ocean lots 

of pollution. Hey government! have uy heard there is a GIANT dump in the middle of the pacific 

ocean, circulating at a growing size that is already twice the size of Texas?! 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1078 of 1099

Start addressing the things that really matter 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0165 

EPA Comment ID: 28376 

EPA Comment Code: 7000 

 

Comment: AIRPLANES DUMP FUEL EACH TIME THEY LAND & USUALLY OVER 

WATER ,INCLUDING DRINKING WATER . WE NEED TO PURIFY OUR DRINKING 

WATER BETTER TO REMOVE CONTAMIN ATES LIKE "PERCHLORATE" . 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0179 

EPA Comment ID: 28384 

EPA Comment Code: 7000 

 

Comment: Our water is more important than most of us know. Keeping polutants such as jet fuel 

out of the water is crucial. We have so many more cancers, birth defects, and illnesses than ever 

before, it's not a difficult stretch to believe our water quality is part of the problem. Please tighten 

water quality regulations today. 

Response: See response to comment code 7000. 

Commenter Name: Charyl Curry Gargel 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0216 

EPA Comment ID: 28390 

EPA Comment Code: 7000 

 

Comment: I am a very concerned business owner and citizen that is very concerned about our 

drinking water.Documents are showing an extremely dangerous amounts of the agent 

PERCHLORATE going into our aquafiers.Please investigate and take remediation action to correct 

this for the sake of our citizens. 

Thank You Charyl Curry Gargel 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0240 

EPA Comment ID: 28418 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1079 of 1099

EPA Comment Code: 7000 

 

Comment: Hey, let's PROTECT the water supply and not bow to corporate interests that want to 

make money at the expense of public health. 

Response: See response to comment code 7000. 

Commenter Name: Terrence O'Brien 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0302 

EPA Comment ID: 28433 

EPA Comment Code: 7000 

 

Comment: I have been involved in Pharmaceutical manufacturing for over 25 years. I, more than 

most people, appreciate the potential impact that even minute quantities of chemical compounds 

can have on peoples health. Please pursue polluters and protect innocent consumers of this country. 

That is why your organization was created. I shouldn't have to worry about Perchlorate, MTBE or 

other industrial compounds in my drinking water. 

Sincerely, Terrence O'Brien Louisville, CO 

Response: See response to comment code 7000. 

Commenter Name: Sandra Chamberlin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0306 

EPA Comment ID: 28434 

EPA Comment Code: 7000 

 

Comment: What is more basic and necessary than to have safe, clean drinking water. We must do 

everything for ourselves and our children, to protect rather than pollute our water. No one should 

have the right to harm others! Drinking is not a choice, it is life itself. Please help reverse the damage 

we've done and do not continue to contaminate. 

Thank you , Sandra Chamberlin Montclair, NJ 07042 21 Edgewood Rd. 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0308 

EPA Comment ID: 28436 

EPA Comment Code: 7000 

 

Comment: Keep our waters clean, for our children and families! 

Response: See response to comment code 7000. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1080 of 1099

Commenter Name: D. Reynaud 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0319 

EPA Comment ID: 28441 

EPA Comment Code: 7000 

 

Comment: Please give us more strongly enforced protections for our nation's water supplies! 

Response: See response to comment code 7000. 

Commenter Name: John Bachalis 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0344 

EPA Comment ID: 28449 

EPA Comment Code: 7000 

 

Comment: I don't understand why there should be any question of whether we should keep any 

kind of poisons out of our drinking water. Don't we all need water to live? I see no reason for 

harmful chemicals or any kind, governmental or commercial to be allowed in our waters. 

Do your job, and keep our water, air and land free of poisons. 

John Bachalis, Yardley, PA 19067-1617 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0351 

EPA Comment ID: 28452 

EPA Comment Code: 7000 

 

Comment: It defys logic that this discussion is happening. Because it is poison it is driving medical 

costs. With 17% of GDP going to medical, and that has gone up 1% since I have been following the 

number over the last five years, where have you been? You need to be looking at Periodic Table 

metals to really solve societal issues, What are my taxes paying for, a debate on how poison is 

poison? Commen sense people, not hogwash is needed from people that I pay. 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0358 

EPA Comment ID: 28454 

EPA Comment Code: 7000 

 

Comment: It is absolutely ludicrous to allow toxic poison in our drinking water. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1081 of 1099

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0362 

EPA Comment ID: 28456 

EPA Comment Code: 7000 

 

Comment: How does a harmful chemical that comes from rocket fuel get in so many public 

waterways? Where is this rocket fuel made? Why are we eventually bathing and drinking it? 

Response: See response to comment code 7000. 

Commenter Name: Larry Ladd 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0372 

EPA Comment ID: 28458 

EPA Comment Code: 7000 

 

Comment: I have already submitted comment 80a1871f, and I would like that comment to be 

attributed to myself, Larry Ladd, rather than "anonymous." I also would like to make a correction to 

the above 

Comment: "with the parvovirus outbreaks in Dharan after Patriot missile deployment, Badr 2002 

pmed 11938419," should read "with the parvovirus outbreaks in Dharan after Patriot missile 

deployment, Mallouh & Qudah 1995 pmed 7715986." 

Larry Ladd 11064 Santiam River Court Rancho Cordova CA 95670 http://www.perchlorate.org 

Response: EPA has made these corrections. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0374 

EPA Comment ID: 28459 

EPA Comment Code: 7000 

 

Comment: Please, we let so much garbage into our food supply; excrement in meat, pesticides, 

growth hormones, at least keep the water as pure as possible! Spare no expense to ensure it stays 

that way 

Response: See response to comment code 7000. 

Commenter Name: Ruth Neifeld 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0402 

EPA Comment ID: 28468 

EPA Comment Code: 7000 

 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1082 of 1099

Comment: I do not know if this note is addressed to the correct agency. I am writing to ask that 

you help all Americans by ensuring that our drinking water is safe. I have been reading of many 

instances where this is not the case. We need someone in government to take on this task. 

Thank you for your interest. Ruth Neifeld 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0406 

EPA Comment ID: 28469 

EPA Comment Code: 7000 

 

Comment: I support limiting chemicals in our drinking water. 

Response: See response to comment code 7000. 

Commenter Name: Ed Thomas 

Commenter Organization: National Rural Water Association (NRWA) 

EPA Document ID: EPA-HQ-OW-2009-0297-0521 

EPA Comment ID: 28477 

EPA Comment Code: 7000 

 

Comment: In closing we find it inexplicable that the Agency was able to interpret the statutory 

standard of what determines the "meaningful opportunity for health risk reduction" and make a 

determination in a relative short period of time. But, on the other hand, the Agency has not been 

able to interpret nor make a determination on similar statuary standards of "unreasonable risk to 

health" (URTH) [42USC300g-5(a)(3)] or "protective of public" [42USC300g-1(b)(15)(B)]. What we 

find inexplicable is that the determination EPA has failed to make heretofore is more pressing to 

community water supplies than the determination EPA recently made for perchlorate. We believe 

that EPA should identify the URTH levels and what constitutes "protective of public health". 

We thank you for the opportunity to provide comments regarding this important matter. 

Sincerely, 

Ed Thomas 

Electronic Attachments: 1. Rubin trade off health risk final.pdf 

Response: See response to comment code 7000. 

Commenter Name: James Talbot 

Commenter Organization: Neverland Designs 

EPA Document ID: EPA-HQ-OW-2009-0297-0456 

EPA Comment ID: 28587 

EPA Comment Code: 7000 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1083 of 1099

 

Comment: Please put people above industry and keep our water pure 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0457 

EPA Comment ID: 28588 

EPA Comment Code: 7000 

 

Comment: Keep our water clean, when it's gone, it's gone! It's very simple, no water = no life. Stop 

playing to big business. 

Response: See response to comment code 7000. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0513 

EPA Comment ID: 28604 

EPA Comment Code: 7000 

 

Comment: Keep water clean! 

Response: See response to comment code 7000. 

Commenter Name: James Evangelos 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0548 

EPA Comment ID: 28762 

EPA Comment Code: 7000 

 

Comment: To those in the EPA, 

Why wouldn't you prevent this chemical from entering our waterways? How you could you think, 

that to some degree, this couldn't be harmful? Where are your standards? Frankly,would you want 

your own children exposed? Consider adopting a life of higher expectation; a life driven by the 

desire to do what is more difficult because IT IS THE RIGHT THING TO DO. The right thing to 

do hear is require perchlorate users responsible for the introduction into our water system to find a 

different way of disposing the chemical. Yes, that means money spent on research and development 

in order to create a manageable discarding mechanism. But is the alternative even thinkable: to 

expose our race to a chemical that could limit thyroid gland activity, ultimately leading to infant 

retardation, among a host of other unforeseen effects. I ask you to talk to your soul, deep down and 

see if it FEELS right to do what you are doing. 

Kinldly , James Evangelos 

Response: See response to comment code 7000. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1084 of 1099

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0557 

EPA Comment ID: 28765 

EPA Comment Code: 7000 

 

Comment: I am concerned about perchlorate in my drinking water. Please help keep it clean! 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0561 

EPA Comment ID: 28768 

EPA Comment Code: 7000 

 

Comment: It doesn't suprise me that you think perchlorate is ok in drinking water when you think 

HsiF is ok despite your 7,000 EPA Uniion workers asking for a moratorium on it. Despite the fact 

that you have no safety documentation on this product. Despite the 3 plus year review of recent 

science on fluoride with it's conslusion saying fluoridation should cease. When will you do the job 

you are being paid to do? Does the word INTEGRITY mean anything to you? Does SCIENCE 

mean anything to you? You have proven that these words don't enter into the decisions you make. 

Response: See response to comment code 7000. 

Commenter Name: Robert Scrima Sr. 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0569 

EPA Comment ID: 28771 

EPA Comment Code: 7000 

 

Comment: It is essential that our drinking water is healthy.Perchlorate is known to be very 

damaging especially to fetuses and young children. It has been shown to be very destructive to all 

humans. 

In the past America maintained safe drinking water.The long term health costs to not doing so are 

enormous.The tragedy of illness caused by contaminates should be avoided at all costs. 

Sincerely, Robert Scrima Sr. 727 Cassandra Lane Lakeland, FL 33809 

Response: See response to comment code 6120. 

Commenter Name: Peter Galvin 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0600 

EPA Comment ID: 28778 

EPA Comment Code: 7000 
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Comment: As a former federal regulator, I would like to urge you to keep the requirements and 

purpose of the law in mind in making your decision on this matter. Too frequently in recent years 

we have delayed or watered down necessary health actions because of fear of junk science submitted 

by impacted industries. Our counsel fall victim to fear of the lawsuit, and our leaderships fall victim 

to fear of individual congressional members responding to pressure from business organizations. 

The public has given you a mandate to protect water quality, and you should not hesitate to fulfill 

that expectation. 

Peter Galvin 

Response: See response to comment code 6120. 

Commenter Name: Anonymous 

Commenter Organization: 

EPA Document ID: EPA-HQ-OW-2009-0297-0609 

EPA Comment ID: 28780 

EPA Comment Code: 7000 

 

Comment: Mercury, perchlorate and raw sewage....what else? Why worry we will be under the 

Obama health plan!? 

Response: See response to comment code 7000. 

Commenter Name: 

Commenter Organization: Seeds of Hope 

EPA Document ID: EPA-HQ-OW-2009-0297-0632 

EPA Comment ID: 28791 

EPA Comment Code: 7000 

 

Comment: Clean up the water-that's why we're using the healthcare system too much. We're sick 

because of contaminated water. 

Response: See response to comment code 7000 

 
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EPA Comment Code: 7100 N/A May 2007 Comments 

Response to Code 7100: Prior to publishing its preliminary regulatory determination for 

perchlorate (73 FR 60262, October 10, 2008) and its supplemental request for comment on the 

perchlorate regulatory determination (74 FR 41883, August 19, 2009), the Agency published a 

summary of the available information relevant to the perchlorate regulatory determination as part of 

its preliminary determination for 11 other contaminants on the second contaminant candidate list 

(72 FR 24016, May 1, 2007). EPA did not make a determination for perchlorate in the May, 2007 

notice but rather described the available information relevant to the perchlorate regulatory 

determination and the steps the Agency planned to take to gather the information needed to make a 

regulatory determination. EPA received a number of comments related to perchlorate in response to 

this request. These comments are compiled in this section. See response to comment code 6120 for 

a discussion of EPA’s decision to regulate perchlorate in drinking water. EPA’s response to 

comments on the regulatory determinations for other contaminants under CCL 2 can be found at 73 

FR 44251, July 30, 2008. 

Individual Comments 

Commenter Name: Marcia Willhite 

Commenter Organization: Illinois Environmental Protection Agency 

EPA Document ID: EPA-HQ-OW-2007-0068-0155 

EPA Comment ID: 20256 

EPA Comment Code: 7100 

 

Comment: 217/785-478 May 23, 2007 Walter Docket Environmental Protection Agency Mailcode: 

2822T 1200 Pennsylvania Ave, NW., Washington DC, 20460 Docket ID No: EPA--HQ--W--2007--

0068 

To Whom It May Concern: 

Thank you for the opportunity to comment on the United States Environmental Protection 

Agency's ("Agency") Regulatory Determinations Regarding Contaminants on the Second Drinking 

Water Contaminant Candidate List - Preliminary Determinations notice. In the notice it indicates 

that the Agency is seeking comment on 11 preliminary determinations. In addition, the notice stated: 

While the Agency has not made a preliminary determination for perchlorate, this action provides an 

update on the Agency's evaluation of perchlorate. The Agency requests public comment on the 

information and the options that the Agency is considering in the evaluating Perchlorate and 

welcomes the submission of relevant, new information and/or data that may assist the Agency in its 

regulatory determination. (Emphasis added) 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Marcia Willhite 

Commenter Organization: Illinois Environmental Protection Agency 

EPA Document ID: EPA-HQ-OW-2007-0068-0155 

EPA Comment ID: 20259 

EPA Comment Code: 7100 
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Comment: Further, the two carcinogens, 2,4-dinitrotoluene, and 2,6-dinitrotoluene have been 

found in groundwater in numerous locations in Illinois, including Joliet Army Ammunition Plant at 

10,000 μg/l, and Savanna Army Depot at 58.8 μg/l, respectively. These chemicals have caused, 

threatened, and allowed contamination of Class I: Potable Resource Groundwater in Illinois. 

Thank you again for the opportunity to comment on this important matter. If you have any 

questions please contact Richard P. Cobb of my staff at the number referenced above. 

Sincerely, Marcia Willhite,Chief Bureau of Water 

Response: This comment is outside of the scope of this action, no response necessary. EPA’s 

response to comments on the regulatory determinations for other contaminants under CCL 2 can be 

found at 73 FR 44251, July 30, 2008. 

Commenter Name: Peter King 

Commenter Organization: American Public Works Association (APWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0156 

EPA Comment ID: 20260 

EPA Comment Code: 7100 

 

Comment: May 29, 2007 Water Docket US Environmental Protection Agency Mail Code 2822T 

1200 Pennsylvania Avenue, NW Washington, DC 20460 DOCKET ID. NO: EPA-HQ-OW-2007-

0068 

 Dear Assistant Administrator Grumbles: 

The American Public Works Association (APWA) appreciates this opportunity to file comments on 

the proposed Regulatory Determinations Regarding Contaminants on the Seeond Drinking Water 

Contaminant Candidate List - Preliminary Determinations (72 FR 24016 (May 1, 2007)) and we 

agree with the decision announced in this notice. These comments were developed through input 

from APWA's Water Resources Management Committee. 

APWA supports the Environmental Protection Agency's (EPA) efforts in making sound 

determinations as to whether or not a National Primary Drinking Water Regulation (NPDWR) 

should be developed for certain unregulated chemical contaminants under the Safe Drinking Water 

Act. The members of APWA's Resources Management Committee agree with the Agency's 

preliminary determination that a NPDWR is not appropriate for the eleven contaminants considered 

by EPA in this notice. 

Response: No response is necessary to the information provided by the commenter. EPA’s 

response to comments on the regulatory determinations for other contaminants under CCL 2 can be 

found at 73 FR 44251, July 30, 2008. 

Commenter Name: Peter King 

Commenter Organization: American Public Works Association (APWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0156 

EPA Comment ID: 20262 
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EPA Comment Code: 7100 

 

Comment: APWA represents 29,000 members who design, build, operate and maintain 

transportation, water supply, sewage and refuse disposal systems, public buildings, and other 

structures and facilities essential to the economy and way of life. Public works professionals serve a 

diverse range of local communities, municipalities, counties, townships, villages and districts, 

whether large or small, urban or rural. As stewards of public infrastructure, APWA members are 

dedicated to managing and operating water systems that provide safe and reliable service to their 

communities. 

Please do not hesitate to contact APWA's Washington Office if we can be of help to you in the 

future. 

Sincerely, Peter King Executive Director 

Response: No response is necessary to the information provided by the commenter. 

Commenter Name: Krista Clark 

Commenter Organization: Association of California Water Agencies 

EPA Document ID: EPA-HQ-OW-2007-0068-0157 

EPA Comment ID: 20263 

EPA Comment Code: 7100 

 

Comment: June 11, 2007 Ms. Cynthia Dougherty Office of Groundwater and Drinking Water U.S. 

Environmental Protection Agency 1200 Pennsylvania Ave. NW Washington, DC 20460 

 Re: May 1st Federal Register Notice for Preliminary Regulatory Determinations Regarding 

Contaminants on the Second Drinking Water Contaminant Candidate List (EPA-HQ-OW-2007-

0068) 

Dear Ms. Dougherty: 

The Association of California Water Agencies (ACWA) would like to request an extension of the 60-

day comment period on the May 1st Federal Register notice for the Preliminary Regulatory 

Determinations Regarding Contaminants on the Second Drinking Water Contaminant Candidate 

List. 

Response: See response to comment ID 20264 under comment code 7100. 

Commenter Name: Krista Clark 

Commenter Organization: Association of California Water Agencies 

EPA Document ID: EPA-HQ-OW-2007-0068-0157 

EPA Comment ID: 20264 

EPA Comment Code: 7100 

 

Comment: Our request for an extension to 120 days is driven by the complexity of the issues, 

including perchlorate, and the large volume of supplementary information not included in the 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Federal Register notice that must be considered before any comments, if necessary, are submitted to 

the Agency. 

Response: After careful review and consideration of the comments EPA received on the May 2007 

notice, the Agency made a final determination in July of 2008 that no regulatory action was 

appropriate for any of the 11 CCL 2 contaminants. However, EPA has provided 2 opportunities for 

further comment on the perchlorate regulatory determination (please refer to the following Federal 

Register Notices: 73 FR 60262, October 10, 2008 and 74 FR 41883, August 19, 2009). 

Commenter Name: Krista Clark 

Commenter Organization: Association of California Water Agencies 

EPA Document ID: EPA-HQ-OW-2007-0068-0157 

EPA Comment ID: 20265 

EPA Comment Code: 7100 

 

Comment: ACWA believes the Contaminate Candidate List (CCL) is a critical element in 

developing drinking water standards. There are extensive policy and science issues involved in 

crafting and implementing this list, and as such, any related regulatory determinations should be 

thoroughly and carefully reviewed. 

If you have any questions, do not hesitate to call me at 916-441-4545. 

Sincerely, Krista Clark Director of Regulatory Affairs 

Response: See response to comment ID 20264 under comment code 7100. 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0162 

EPA Comment ID: 20266 

EPA Comment Code: 7100 

 

Comment: July 2, 2007 U.S. Environmental Protection Agency Office of Water Docket (Mailcode 

2822T) 1200 Pennsylvania Ave. NW Washington, DC 20460 

 RE: Regulatory Determinations Regarding Contaminants on the Second Drinking Water 

Contaminant Candidate List-Preliminary Determinations Docket EPA-HQ- OW-2007-0068 

Dear Docket: 

The American Water Works Association appreciates the opportunity to comment on the preliminary 

regulatory determinations from the second Contaminant Candidate List (CCL2) as detailed in the 

May 1st Federal Register notice (72 FR 24016). AWWA is an international, nonprofit, scientific and 

educational society dedicated to the improvement of drinking water quality and supply. Founded in 

1881, the Association is the largest organization of water supply professionals in the world. Our 

60,000 plus members represent the full spectrum of the drinking water community: treatment plant 

operators and managers, environmental advocates, engineers, scientists, academicians, and others 

who hold a genuine interest in water supply and public health. Our membership includes more than 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1090 of 1099

4,700 utilities that supply roughly 80 percent of the nation's drinking water. Based on this broad 

membership base, these comments should be considered as representative of the drinking water 

community in general. These comments are divided into two major sections, starting with general 

comments, and then followed by comments on specific contaminants discussed in the May 1st 

Federal Register notice. 

General Comments 

As previously mentioned, AWWA appreciates the opportunity to comment on the above referenced 

preliminary regulatory determinations. The Contaminant Candidate List (CCL) and subsequent 

regulatory determinations are the foundation for the standardsetting process resulting from the 1996 

Safe Drinking Water Act (SDWA) Amendments. These two components are among the most 

important changes in EPA’s approach for developing national drinking water regulations since the 

SDWA was initially passed in 1974. Ensuring that the appropriate contaminant is selected for 

regulation is the critical first step in the development of national drinking water regulation that 

should subsequently be followed by setting the standard at the appropriate level for that 

contaminant. 

The May 1st Federal Register address the preliminary regulatory determinations from CCL2 and the 

CCL process and the subsequent regulatory determinations are intertwined. AWWA has significant 

concerns with the parallel ongoing process for the third Contaminant Candidate List (CCL3) and 

those concerns will be sent in a separate letter to Cynthia Dougherty upon submission of these 

comments. 

Section 1412(b)(1)(A) of the 1996 SDWA Amendments details the criteria for identification of 

contaminants for potential regulation: 

i. the contaminant may have an adverse effect on the health of persons; ii. the contaminant is known 

to occur or there is a substantial likelihood that the contaminant will occur in public water systems 

with a frequency and at levels of public health concern; and iii. in the sole judgment of the 

Administrator, regulation of such contaminant presents a meaningful opportunity for health risk 

reduction for persons served by public water systems. 

Another reform that is particularly applicable to this notice is found in Section 1412(b)(3)(A): 

In carrying out this section, and, to the degree that an Agency action is based on science, the 

Administrator shall use - 

(i) the best available, peer-reviewed science and supporting studies conducted in accordance with 

sound and objective scientific practices; and (ii) data collected by accepted methods or best available 

methods (if the reliability of the method and the nature of the decision justifies use of the data). 

EPA's preliminary regulatory determinations for eleven contaminants on the second Contaminant 

Candidate List (CCL2) as published in the May 1st Federal Register complies with these two sections 

of the SDWA. AWWA commends EPA for not regulating contaminants purely for the sake of 

regulation, as was the case for some of the 83 contaminants listed in the 1986 SDWA Amendments. 

AWWA also commends EPA for using the best-available, peer-reviewed science in these preliminary 

determinations. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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AWWA agrees with EPA's decision not to regulate these eleven contaminants. The occurrence 

levels are generally low based on national surveys such as the Unregulated Contaminant Monitoring 

Rule (UCMR), and regulation does not present an opportunity for significant risk reduction as 

mandated by the 1996 SDWA Amendments. These preliminary determinations follow the logic 

previously used in July 2003 for the first round of regulatory determinations and for the first six-year 

review (Roberson, 2005). AWWA believes that use of consistent logic in these two parallel 

regulatory efforts is important, contributing to a more transparent process, and commends EPA for 

proceeding in this manner. Based on the first round of regulatory determinations, a range of 0.02%-

3.2% for national occurrence could be considered as the minimum threshold for development of a 

new regulation. National occurrence estimates for these eleven contaminants are well below this 

threshold, with boron having the highest prevalence of occurrence, at 1.7% of systems sampled in 

the National Inorganics and Radionuclides Survey (NIRS). Based on the first six-year review, a range 

of 0.53%-9.28% for national occurrence could be considered as the minimum threshold for revising 

an existing regulation. 

Some might consider the lack of new contaminant regulations since the 1996 SDWA Amendments 

as an indication that this new regulatory development process is not working. AWWA disagrees with 

that viewpoint and believes, rather, that not regulating trivial contaminants is a positive development 

for EPA. Thirteen previously regulated contaminants had zero violations according to SDWIS data. 

Despite the lack of contaminant occurrence at levels of health concern, as inferred from the absence 

of violations for these contaminants, their regulation was nevertheless mandated by 1986 SDWA 

listing (Roberson, 2003). 

A further indication that the new regulatory development process is working properly is the 

successful collection of occurrence data, through the Unregulated Contaminant Monitoring Rule 

(UCMR), to support regulatory determinations. Four of the contaminants (2,6-Dinitrotoluene, 

EPTC, Fonofos, Terbacil) in the current notice have zero occurrence based on the monitoring 

results from the first UCMR (UCRM1). These four contaminants were considered to be of potential 

concern based on the best information at the time back in 1998 when the first Contaminant 

Candidate List (CCL1) was published. UCMR1 monitoring results showed that these four 

contaminants were never detected in any of the more than 3,800 monitored systems. 

AWWA recommends that EPA expand its discussion of the logic underlying the determinations for 

these eleven contaminants. The logic provided in the May 1st notice is not entirely clear. Generally, 

EPA needs to raise the level of transparency in its decision logic so that stakeholders can understand 

how data and information translate to determinations and to ensure consistency across the two 

parallel regulatory efforts (regulatory determinations and six-year review). For example, in the 

current notice there is no discussion about the remaining 40 CCL2 contaminants, what data are 

needed to make regulatory determinations, and what is being done to collect those data. 

Stakeholders have no way of knowing if more information on health effects or occurrence is 

required, or whether analytical methods research is needed before health effects and/or occurrence 

data can be reliably obtained. 

The integration of EPA's overall drinking water research agenda with the overall regulatory 

development process is not sufficiently explained in this notice. The research being done on the 

balance of the contaminants from the second Contaminant Candidate List (CCL2) is not discussed. 

The process for conducting the appropriate research and then making the appropriate regulatory 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1092 of 1099

decision for the 40 remaining contaminants needs to be clearly communicated to the drinking water 

community. For example, although national occurrence data from over 3,800 systems exists for 

acetochlor, molinate, and nitrobenzene, which were included in UCRM1 List 1, these three 

contaminants are not discussed at all in the May 1st Federal Register. It is unclear how the regulatory 

development process is driving EPA's research agenda. 

AWWA recommends that, in the final notice, EPA develop a table on the information gaps for 

chemical contaminants similar to the table of pg. 24052 of the May 1st Federal Register for 

microbial contaminants. The limited research information in the current notice gives the appearance 

that little progress has been made since our 2002 comments on the first round of regulatory 

determinations. There is a strong need for appropriately communicating the body of research on 

CCL contaminants to the water sector. 

AWWA wants to reiterate its concern that the 60-day comment period is not sufficient for 

adequately analyzing the complex issues surrounding perchlorate and for review, in general, of the 

associated background documentation. On May 22nd, AWWA requested an extension of the public 

comment period to 120 days and this extension was not granted. Not granting the requested 

extension is unfortunate, as the short comment period does not allow for adequate review by the 

drinking water community of the background documentation and for adequate debate on the 

complex policy issues. Perchlorate has been on EPA’s regulatory agenda since its inclusion on the 

draft of the first CCL in 1997. While EPA has had over a decade to work through the complex 

policy issues surrounding perchlorate, the drinking water community had only 60 days to sift 

through these issues and make the appropriate policy decision. 

Response: No response is necessary to the specific recommendations regarding transparency and 

information gaps as these comments were addressed in the July 2008 notice (73 FR 44255, July 30, 

2008). Regarding the comment about perchlorate, please see response to comment ID 20264 under 

comment code 7100. 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0162 

EPA Comment ID: 20269 

EPA Comment Code: 7100 

 

Comment: Metolachlor 

AWWA does not have any additional occurrence data on metolachlor or its degradates, but believes 

that more research is needed on the occurrence and health effects of many herbicides and pesticides 

and their degradates. The results of this research then need to be appropriately included in 

regulatory decisions by the Office of Pesticide Programs (OPP) and the Office of Groundwater and 

Drinking Water (OGWDW). 

For example, metolachlor was not included in OPP's Cumulative Risk Assessment (CRA) for the 

chloroacetanilides because it was not apparent from currently available data that it shares the same 

target site in the nasal tissue as acetochlor, alachlor and butachlor, even though it does distribute to 

the nasal turbinates and "might" metabolize to quinoneimine, the active agent (as do acetochlor, 

alachlor and butachlor). Propachlor was also excluded from the Cumulative Risk Assessment for 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

Page 1093 of 1099

similar reasons. EPA should promote further research to definitively determine whether or not 

metolachlor , a very widely used pesticide, is carcinogenic, as acetochlor, alachlor and metolachlor 

have very similar chemical structures. 

The triazine herbicides are another example of the need to obtain the appropriate occurrence and 

health effects data of herbicides and pesticides and their degradates. AWWA has commented 

extensively in the past to OPP on the atrazine reregistration process. AWWA, through the Water 

Industry Technical Action Fund (WITAF) and a partnership with the Awwa Research Foundation 

(AwwaRF), has conducted extensive research on atrazine and its chlorinated metabolites. A listing of 

the published papers resulting from this research is enclosed as Appendix B. 

The need for more occurrence and health effects data increases with the growing concern about 

potential reproductive and developmental effects from many herbicides and pesticides and their 

degradates. These new health endpoints will create monitoring and compliance challenges for water 

utilities, as the typical quarterly compliance monitoring is likely not appropriate for these new health 

endpoints. Both metolachlor and atrazine are on EPA's recently released draft list of 73 pesticides 

for Initial Tier 1 Screening as a potential endocrine disruptor under the Federal Food, Drug, and 

Cosmetic Act. 

Methyl tertiary-butyl ether (MTBE) 

AWWA supports EPA's decision not to make a regulatory determination for methyl tertiary-butyl 

ether (MTBE) at this time as the risk assessment is currently being revised. AWWA does not have 

any additional MTBE data to add to the topics listed in the May 1st Federal Register notice. 

Microbial Contaminants 

An information summary describing the state of the knowledge on the prevention, treatment, and 

health effects of cyanobacteria and its toxins would be useful for utilities and for state primacy 

agencies. The information should be concise and practical to ensure the document will be useful to 

water utility personnel. The summary should also include information on occurrence and conditions 

that might favor growth of algae and production of toxins. A strategy for communicating this 

information to utility customers should also be addressed. In addition to resources generated by 

EPA, the summary should include information of research funded by other organizations, 

particularly Awwa Research Foundation (AwwaRF). 

Again, AWWA appreciates the opportunity to comment on these important drinking water issues. If 

you have any questions about these comments, please feel to call Alan Roberson or me in our 

Washington Office at 202-628-8303. 

Yours Sincerely, Thomas W. Curtis Deputy Executive Director 

cc: Ben Grumbles - USEPA OW Cynthia Dougherty - USEPA OGWDW Audrey Levine - USEPA 

ORD Brian Mannix - USEPA OPEI Alan Roberson Steve Via 

P:\Regulatory\Comments\2007\ RegDet2 Comments JAR 7207.doc 

 [APPENDIX A - see PDF] [APPENDIX B - see PDF] 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Response: See response to comment ID 20264 under comment code 7100. 

Commenter Name: Ed Thomas 

Commenter Organization: National Rural Water Association (NRWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0163 

EPA Comment ID: 20270 

EPA Comment Code: 7100 

 

Comment: July 2, 2007 U.S. Environmental Protection Agency Office of Water Docket (Mailcode 

2822T) 1200 Pennsylvania Ave. NW Washington, DC 20460 

RE: Regulatory Determinations Regarding Contaminants on the Second Drinking Water 

Contaminant Candidate List-Preliminary Determinations (Docket Number: EPA- HQ-OW-2007-

0068) 

To Whom It May Concern: 

NRWA commends EPA for it's caution in withholding regulatory action on the 11 contaminants 

reviewed to date under the second contaminant candidate listing process (CCL2) and concurs with 

EPA recommendations in this regard. NRWA's position concerning these 11 contaminants, as well 

as the remaining candidates on the list, is influenced primarily by two recent papers that bear directly 

on the occurrence data and the risk evaluations that are an integral part of the CCL review. 

Response: See response to comment ID 20264 under comment code 7100. 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0166 

EPA Comment ID: 20274 

EPA Comment Code: 7100 

 

Comment: July 2, 2007 U.S. Environmental Protection Agency Office of Water Docket (Mailcode 

2822T) 1200 Pennsylvania Ave. NW Washington, DC 20460 

RE: Regulatory Determinations Regarding Contaminants on the Second Drinking Water 

Contaminant Candidate List-Preliminary Determinations; Docket EPA-HQ-OW- 2007-0068 

The Association of Metropolitan Water Agencies (AMWA) appreciates the opportunity to comment 

on the preliminary regulatory determinations for 11 contaminants as listed in the May 1, 2007 

Federal Register (72 FR 24016). AMWA strongly supports the process required by the 1996 

Amendments to the Safe Drinking Water Act (SDWA) that identifies potential contaminants, 

gathers needed information to determine if a national regulation is needed, and presents a formal 

evaluation and determination on whether or not to regulate a given contaminant. 

Prior to the 1996 Amendments, Congress required regulation of specific contaminants based solely 

on the first step of the current process - the listing of potential contaminants. This lead to regulation 

of numerous contaminants that did not appear in drinking water at levels of public health concern 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1095 of 1099

and wasted limited EPA and public resources. AMWA believes that this notice demonstrates that 

the 1996 process can work well in that the highest priority contaminants are selected for evaluation 

and that evaluation leads to informed decisions. 

AMWA supports each of the 11 regulatory determinations made. 

Response: See response to comment ID 20264 under comment code 7100. 

Commenter Name: James Taft 

Commenter Organization: Association of State Drinking Water Administrators (ASDWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0169 

EPA Comment ID: 20284 

EPA Comment Code: 7100 

 

Comment: July 2, 2007 Comment Clerk Docket EPA-HQ-OW-2007-0068 Water Docket 

Environmental Protection Agency Mail Code: 2822T 1200 Pennsylvania Ave., NW. Washington, 

DC 2046 0 

Dear Sir: 

In response to the notice in the Federal Register of May 1, 2007 (Volume 72, Number 83) the 

Association of State Drinking Water Administrators (ASDWA) would is offering comments to the 

U.S. Environmental Protection Agency (EPA) on the Regulatory Determinations Regarding 

Contaminants on the Second Drinking Water Contaminant List -- Preliminary Determinations; 

Proposed Rule. ASDWA is the professional Association that represents the collective interests of 

the nation's state drinking water programs responsible for implementation of the Federal Safe 

Drinking Water Act. 

 Although some states have the expertise and resources to conduct their own evaluations of 

contaminant risk and may set their own, more stringent regulatory controls, most states rely on the 

EPA to determine which contaminants should be regulated in drinking water. It is critical that these 

determinations are based on sound science and accomplished through a transparent process with 

adequate input from all interested parties, especially the states. States expect EPA to follow the 

process prescribed in the Safe Drinking Water Act and we support the three statutory criteria for 

regulatory determinations: 

(1) the contaminant may have an adverse effect on the health of persons; 

(2) the contaminant is known to occur or there is substantial likelihood that the contaminant will 

occur in public water systems with a frequency and at levels of public health concern; and 

(3) in the sole judgment of the Administrator, regulation of such contaminant presents a meaningful 

opportunity for health risk reduction for persons served by public water systems. 

ASDWA appreciates the opportunity to provide the perspective of states on EPA's preliminary 

determination of which contaminants from the second Contaminant Candidate List (CCL2) should 

be regulated. States are generally in favor of the regulatory decisions that EPA is proposing in this 

notice but we do have a few comments to offer. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1096 of 1099

States generally agree there is no significant occurrence nor any "meaningful opportunity for health 

risk reduction" in regulating the 11 contaminants EPA has preliminarily decided not to regulate. One 

state indicated that dacthal and its degradates did appear in some drinking water system monitoring 

in their state but that it could be effectively managed in the absence of a federal regulation. 

Therefore, ASDWA supports EPA's decision not to regulate the 11 contaminants on the list in the 

May 1, 2007 proposal. 

Response: See response to comment ID 20264 under comment code 7100. 

Commenter Name: James Taft 

Commenter Organization: Association of State Drinking Water Administrators (ASDWA) 

EPA Document ID: EPA-HQ-OW-2007-0068-0169 

EPA Comment ID: 20288 

EPA Comment Code: 7100 

 

Comment: Metolachlor and Methyl tertiary-butyl-ether (MTBE): 

As stated in the Federal Register notice, EPA's primary need here is for additional contaminant 

occurrence data to support its regulatory decisions. Monitoring conducted by water systems under 

UCMRI and coming under UCMR2 will provide a solid base of occurrence data for future 

determinations. Many states have assisted EPA in implementing the UCMR monitoring to help 

assure that systems monitor and report as required. We believe these new data will add significantly 

to EPA's knowledge of the occurrence of contaminants on the Contaminant Candidate Lists and 

others considered for regulation. 

Thank you for your consideration of these comments. Please contact me at 703-812-9507 or 

jtaft@asdwa.org if we can provide additional information or if any clarification of these comments is 

needed. 

Sincerely, James D. Taft Executive Director 

Response: See response to comment ID 20264 under comment code 7100. 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1097 of 1099

Appendix 1 – Complete List of EPA Comment Codes 

Comment 

Code Comment Topics 

Comment Code 

Used? 

1000 General Comments Y 

1100 SDWA requirements and the CCL and Regulatory Determinations 

process 

Y 

1200 

EPA’s handling in the October 2008 FR Notice of perchlorate-related 

comments that were submitted following the May 2007 RegDet2 FR 

Notice 

N 

1300 Length of the comment period following the October 2008 FR Notice Y 

1400 Supplemental Request for Comments 

1500 EPA's handling of comments on the October 2008 FR Notice Y 

1600 Length of the comment period following August 2009 FR Notice Y 

2000 Perchlorate Health Effects Y 

2100 NAS (NRC) review of perchlorate health effects and reference dose Y 

2110 Regulatory determination based upon the already-established RfD Y 

2150 EPA's decision not to seek further input from the NRC on issues 

related to perchlorate Y 

2200 Use of NHANES biomonitoring data for health effects evaluation Y 

2300 Use of PBPK models from Clewell et al (2007) and Merrill et al (2005) 

to evaluate health effects Y 

2400 Use of EPA’s PBPK model to evaluate health effects Y 

2410 Use of PBPK model to select life-stage-specific HRLs Y 

2420 Suggestions for alternative ways to use the PBPK model to inform the 

regulatory determination Y 

2500 

Other health effects studies, models, and data for EPA to consider 

(besides NAS/NRC report, NHANES biomonitoring data, and PBPK 

models already evaluated) 

Y 

2600 Comments on expanding scope of risk assessment to include other 

goitrogens and/or dietary iodide deficiency Y 

3000 Perchlorate Occurrence in Drinking Water Y 

3100 UCMR 1 occurrence analysis Y 

3110 UCMR 1 analytical methods and minimum reporting limits (MRL) N 

3120 UCMR 1 statistical methodology and nationally representative sample 

of small systems Y 

3130 UCMR 1 schedule and sampling plan N 

3140 UCMR 1 entry-point-level estimation of perchlorate exposure Y 

3150 Potential use of a Bayesian model to estimate number of PWSs and 

population served at a range of thresholds Y 

3160 Use of Census data to estimate populations that are in the sensitive life 

stage 

Y 

3170 Accounting for variation of perchlorate levels in public water systems 

over time Y 

3200 Supplemental drinking water occurrence data from California and 

Massachusetts Y 

3300 Other drinking water occurrence studies, models, and data for EPA to 

consider (besides UCMR 1 and California and Massachusetts data Y 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

 Comment Response Document January 2011 

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Comment 

Code Comment Topics 

Comment Code 

Used? 

already evaluated) 

4000 Evaluation of Perchlorate Exposure from Sources Other than 

Drinking Water Y 

4100 Dietary studies N 

4110 Dietary studies -- FDA’s 2005-2006 total dietary study (TDS) Y 

4120 Dietary studies -- FDA’s 2003-2005 exploratory survey data on 

perchlorate in food N 

4130 Dietary studies -- other studies, models, and data (besides FDA’s 2005-

2006 TDS, and 2003-2005 exploratory data) Y 

4200 Biomonitoring N 

4210 Biomonitoring -- urinary data from the 2001-2002 NHANES study, 

and EPA/CDC’s NHANES-UCMR analysis Y 

4220 Biomonitoring -- breast milk studies discussed in the notice Y 

4230 

Biomonitoring -- other biomonitoring studies, models, and data for 

EPA to consider (other than NHANES and breast milk studies 

discussed in the notice) 

Y 

4300 Other perchlorate exposure studies, models, and data for EPA to 

consider (other than drinking water, diet, and biomonitoring) Y 

5000 SDWA Criteria Y 

5100 SDWA Criterion #1 -- EPA’s determination that perchlorate may have 

adverse effects on the health of persons Y 

5200 SDWA Criterion #2 -- EPA’s determination that perchlorate occurs 

infrequently at levels of health concern in public water systems Y 

5210 Derivation of the RSC Y 

5220 Derivation of the HRL Y 

5225 Use of alternative HRLs specific to sensitive life stages, as described in 

Table 2 of the August 2009 FR notice. Y 

5230 Calculation of frequency of exposure above the HRL among pregnant 

women 

Y 

5240 

Consideration of other sensitive subpopulations (e.g., infants, children, 

and persons with iodine deficiency or thyroid disorders) when 

establishing the HRL 

Y 

5300 

SDWA Criterion #3 -- EPA’s determination that regulating perchlorate 

with a NPDWR would not represent a meaningful opportunity to 

reduce health risks for persons served by public water systems 

Y 

6000 EPA Actions Y 

6100 EPA’s preliminary determination not to regulate perchlorate Y 

6110 Comments urging EPA not to regulate perchlorate Y 

6120 Comments urging EPA to regulate perchlorate Y 

6125 Comments critical of preliminary determination (in the October 2008 

FR Notice) specific to Washington Post article Y 

6130 Miscellaneous comments on the preliminary determination not to 

regulate (in the October 2008 FR Notice) Y 

6140 Additional new literature and information for EPA to consider when 

making a regulatory determination Y 

6200 Comments related to EPA’s health advisory Y 

6210 Need for EPA to provide additional support to States and water 

systems 

Y 
EPA-OGWDW Final Perchlorate EPA 815-R-10-005 

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Page 1099 of 1099

Comment 

Code Comment Topics 

Comment Code 

Used? 

6300 EPA’s intention to revise guidance on clean-up levels (preliminary 

remediation goals) Y 

6310 Clean-up as a solution Y 

6400 EPA’s decision to subject updated PBPK model to peer review during 

comment period (in the October 2008 FR Notice) Y 

6500 Comments on alternative risk reduction approaches Y 

7000 Miscellaneous Comments Y 

7100 N/A May 2007 Comments Y