Docket Number EPA-HQ-OPP-2015-0303 

www.regulations.gov 

Penoxsulam Preliminary Work Plan 

Registration Review: Initial Docket 

Case Number 7625 

Approved by: 

Date: 

September 2015 

Ghc-t~ r· ~qu..-~ ,')} 

Richard P. Keigwin, Jr. 

Director 

Pesticide Re-evaluation Division 
Penoxsulam Preliminary Work Plan - Table of Contents 

OVERVIEW .................................................................................................................................... 4 

ANTICIPATED OAT A NEEDS ....... ........ ...................................................................................... 5 

STATUTORY AND REGULATORY AUTHORITY ................................................................... 5 

CHEMICAL FACTS .. ...... ......................................... ........ ................. ...... ........ ............................... 6 

USE AND USAGE INFORMATION ............................................................................................. 6 

RECENT ACTIONS ....................................................................................................................... 7 

ANTICIPATED RISK ASSESSMENTS FOR REGISTRATION REVIEW ................................. ? 

TIMELINE .................................................................................................................................... ! 0 

NEXT STEPS .... .... ..... ........................... ........ ........................ ............................... ......................... I 0 

Appendix - Additional Areas Considered in the Penoxsulam Registration Review ................. I 1 

References: 

This Preliminary Work Plan summarizes the Environmental Protection Agency's cmTent position 

based on the following documents: 

1. Registration Review Ecological Risk Assessment for Penoxsufam. James Wolf, Ph.D. and 

Rosanna Louie-Juzwiak, RAPL. July 17, 2015. 

2. Penoxsulam Human Health Assessment Scoping Document in Support of Registration 

Review. Douglas Dotson, Ph.D.; Linnea Hansen, Ph.D.; Zaida Figueroa, M.S. April 16, 

2015. 

3. Penoxsulam: Tier I Review of Human Incidents. Shanna Recore, Industrial Hygienist; 

Elizabeth Evans, Environmental Protection Specialist. January 28, 2015. 

4. BEAD Chemical Profile (BCP) for Registration Review: Penoxsulam (1 19031). Sunil 

Ratnayake, Biologist; Sepehr Haddad, Environmental Protection Specialist; Stephen 

Smearman, Economist. December 4, 2014. 

2 
5. Penoxsulam Screening Level Usage Analysis. July 2 1, 2014 

6. Penoxsufam (1 19031) Label Use Report Package in Support of Registration Review,· 

September 11, 2014. EFED Table 1 Report 

7. Penoxsufam (119031) Label Use Report Package in Support of Registration Review; 

September 11, 2014. HED Master Table Report. 

These and other supporting documents for the penoxsulam registration review case may be found 

in the docket EPA-HQ-OPP- 2015-0303 at http://www.regulations.gov. 

3 
OVERVIEW 

The docket for penoxsulam is now open, initiating the first public comment period for this 

registration review (docket number EPA-HQ-OPP-2015-0303). Penoxsulam is an herbicide 

belonging to the triazolopyrimidine sulfonamide family. Members of this family, like those in 

the imidazolinone and sulfonylurea herbicide families, work by inhibiting the activity of the 

enzyme acetolactate synthase (ALS). Penoxsulam is a systemic herbicide applied as a postemergence treatment for selective control of annual grasses, sedges, and broad leaf weeds in 

agricultural and non-agricultural use sites. lt is also used for control of vegetation in lakes, 

ponds, canals and reservoirs. This Preliminary Work Plan (PWP) document explains what EPA's 

Office of Pesticide Programs knows about penoxsulam, highlighting anticipated data and 

assessment needs, identifying the types of information that would be especially useful to the 

Agency in conducting the review, and providing an anticipated timeline for completing the 

registration review for penoxsulam. 

The registration review process was designed to include a public participation component to 

solicit input from interested stakeholders. The Agency intends, by sharing this infotmation in the 

docket, to infonn the public of what it knows about penoxsulam and what types of new data or 

other information would be helpful for the Agency to receive as it moves toward a decision on 

penoxsulam. The Agency encourages all interested stakeholders to review the PWP and 

Appendix and to provide comments and additional information that will help the Agency's 

decision-making process for this chemical. In addition to general areas on which persons may 

wish to comment, there are some areas identified in the PWP and Appendix about which the 

Agency specifically seeks comments and information. Interested stakeholders could include: 

enviromnental non-profit or interest groups; pesticide manufacturers; agricultural labor or 

cormnodity groups; commercial, institutional, residential, and other users of pesticides; or the 

public at large. 

The Agency is releasing a Preliminary Risk Assessment (PRA) for ecological risk concurrent 

with the PWP. Rather than providing a Problem Formulation for planning the ecological risk 

assessment for penoxsulam, as is usual for docket openings, the Agency has already completed a 

preliminary ecological risk assessment. This PRA is included in the penoxsulam registration 

review docket, and the Agency is requesting comments on the PRA as well as the PWP during 

the docket opening comment period. The Agency anticipates completing a pollinator risk 

assessment for penoxsulam after considering data from pollinator studies it anticipates requiring 

for the penoxsulam registration review. 

The Preliminary Work Plan begins by listing the anticipated data needs for penoxsulam. Next, it 

discusses the statutory and regulatory authority for registration review. Then the document 

provides chemical facts, use and usage information, recent actions, infonnation on the 

anticipated risk assessments, and a projected registration review timeline for penoxsulam. 

Finally, the Appendix to this document includes identification and discussion of some areas that 

are considered generally in registration review along with some additional chemical case-specific 

information. 

4 
ANTICIPATED DATA NEEDS 

Table 1 below summarizes anticipated data needs for penoxsulam. For additional discussion of 

the anticipated data needs, see the Registration Review Ecological Risk Assessment for 

Penoxsu/am and Penoxsu/am. Human Health Assessment Scoping Document in Support of 

Registration Review. 

Table 1: Anticipated Data Needs for the Penoxsulam Registration Review 

Estimated 

Guideline Timeframe 

Number Study Title 

Test Material (Months from 

receipt of DCI) 

Non-guideline Acute oral toxicity to larval honey bees 

TGAI 12 (OECD 237) 

Non-guideline Chronic oral toxicity to adult honey bees1 TGAI 12 

Non-guideline Chronic oral toxicity to larval honey bees 1 TGAI 12 

Non-guideline Field trial of residues in pollen and nectar1 TEP 24 

Non-guideline Semi-field testing for pollinator1 TEP 24 

850.3040 Field testing for pollinators TEP 24 

TGAJ = teclmical grade active mgred1ent; TEP = typtcal end-use product. 

STATUTORY AND REGULATORY AUTHORITY 

The Food Quality Protection Act (FQPA) of 1996 mandated a registration review program. All 

pesticides distributed or sold in the United States (U.S.) generally must be registered by the 

Environmental Protection Agency (EPA or the Agency), based on scientific data showing that 

they will not cause unreasonable risks to human health or the environment when used as directed 

on product labeling. The registration review program is intended to make sure that, as the ability 

to assess risk evolves and as policies and practices change, all registered pesticides continue to 

meet the statutory standard of no unreasonable adverse effects to human health or the 

environment. Changes in science, public policy, and pesticide use practices will occur over time. 

Through the registration review program, the Agency periodically reevaluates pesticides to make 

sure that as change occurs, products in the marketplace can be used safely. Information on this 

program is provided on EPA's website.2 

The Agency is implementing the registration review program pursuant to Section 3(g) of the 

Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), and will review each registered 

pesticide every 15 years to determine whether it continues to meet the FIFRA standard for 

registration. The regulations governing registration review begin at 40 CFR 155.40. The 

Agency will consider benefits information and data as required by FIFRA. The public phase of 

registration review begins when the initial docket is opened for each case. The docket is the 

1

Guidance for these studies can be found at: http://www2.epa.gov/pollinator-protection/pollinator-risk-asscssmentguidance. 2 http://www.epa.gov/oppsrrd !/registration review/ 

5 
Agency's opportunity to state what it knows about the pesticide and what additional risk analyses 

and data or information it believes are needed to make a registration review decision. After 

reviewing and responding to comments and data received in the docket during this initial 

comment period, the Agency will develop a Final Work Plan (FWP) and anticipated schedule for 

the registration review of penoxsulam. 

CHEMICAL FACTS 

Table 2 provides a summary of the chemical facts for penoxsulam. 

Table 2: Chemical Facts for Penoxsulam 

PC code 11903 1 

Case Number 7625 

CAS Number 219714-96-2 

Year first registered 2004 

Pesticide Type Herbicide 

Chemical class Triazolopyrimidine sulfonamide 

Reregistration Eligibility Because it was registered after November 1984, penoxsulam was 

Decision (RED) not subject to reregistration. 

Tolerance Reassessment Not applicable. Because it was registered after November 1984, 

Eligibility Decision penoxsulam has not undergone tolerance reassessment. 

(TRED) 

Cumulative group Not applicable. Penoxsulam has not been identified as a member 

of a cumulative group that shares a common mechanism of 

toxicity to humans. 

40 CFR Citation Tolerances for penoxsulam are established in 40 CFR § 180.605. 

Dual-use Penoxsulam is registered for conventional pesticidal uses only 

and has no registered antimicrobial or biopesticidal uses. 

Non-pesticidal uses There are no identified non-pesticidal uses of penoxsulam. 

Pesticide Re-evaluation Bonnie Adler, adler.bonnie@epa.gov, 703-308-8523 

Division, Chemical 

Review Manager 

Registration Division, Heather Garvie, garvie.heather@epa.gov, 703-308-0034 

Product Manager 

USE AND USAGE INFORMATION 

Table 3 summarizes the use and usage information for penoxsulam. Please see the BEAD 

Chemical Profile (BCP) for Registration Review: Penoxsulam (11903 1) in the registration 

review docket for more details. 

Table 3: Penoxsulam Use and Usage Information 

Summary of Use Penoxsulam belongs to the triazolopyrimidine sulfonamide 

family. It is registered for use as a post-emergence treatment to 

control annual grasses, sedges, and broadleaf weeds in 

6 
Table 3: Penoxsulam Use and Usage Information 

agricultural and non-agricultural use sites. It is also registered for 

use on residential sites. 

Use Sites Uses include dry- and wet-seeded rice, turf, tree nuts, grapes, nonbearing fruit trees, and aquatic use sites. 

Summary of Usage From 2005-2012, average annual usage was approximately 6,500 

pounds active ingredient (a.i.) on approximately 207,000 acres 

treated. Usage increased during that time, most noticeably from 2010 

to 2011. Rice accounts for the majority of agricultural usage. 

Formulation Type(s) Soluble/emulsifiable concentrate and granular fonnulations. May 

be co-formulated with other herbicides and with fertilizer. 

Application Method(s) Ground spreaders, aerial sprayers. 

Technical Registrant(s) Dow Agrosciences 

No. of Registrations 51 Section 3 products3 

Restricted Use No 

Guidance for Commenters: 

Data are needed for usage on turf, lawns, lakes, ponds, canals, non-bearing trees, conifers, 

eucalyptus, and non-cropland, in terms of pounds a.i. used annually (ideally for the last several 

years). Data also are needed for each of these sites on individual and maximum annual 

application rates, number of applications/year, minimum retreatment intervals, and application 

timing. 

RECENT AND PENDING ACTIONS 

There are several new uses pending for penoxsulam. These include uses on pome fruit group 11-

10; stone fruit group 12-12; small fruit vine climbing subgroup l3-07F; olive; pomegranate; and 

tree nut group 14-12. 

ANTICIPATED RISK ASSESSMENTS FOR REGISTRATION REVIEW 

The most recent comprehensive human health risk assessment for penoxsulam was completed on 

April 9, 2009 to evaluate proposed new uses on grapes and tree nuts. The most recent ecological 

risk assessment was completed July 17, 2015 for registration review. Findings and conclusions 

from these risk assessments are summarized in the Registration Review Ecological Risk 

Assessment for Penoxsulam and the Penoxsulam Human Health Assessment Scoping Document 

in Support of Registration Review. 

At this time, the Agency is issuing a preliminary ecological risk assessment based on the 

currently available data and prior assessments. The assessment does not include comprehensive 

data for potential risk to honey bees. During registration review, the Agency anticipates the need 

to conduct a comprehensive revised ecological risk assessment, including an endangered species 

3 Section 3 product labels can be obtained from the Pesticide Product Label System (PPLS) website 

(http://oaspub.epa.gov/pestlabVppls.home). 

7 
assessment and an assessment of risks to pollinators, for all uses of penoxsulam. For human 

health, EPA anticipates the need to conduct revised aggregate, residential, and occupational risk 

assessments during registration review. Human health risk assessments will be conducted to 

assess the proposed new uses. 

Table 4 below summarizes the anti cipated registration review risk assessments based on the 

EFED PRA and HED Scoping Document. 

Table 4: Anticipated Risk Assessments for the Penoxsulam Registration Review 

Type of Risk Assessment Conduct? Notes 

Ecological and, Environmental Fate 

Ecological (species to be y The PRA for ecological risk is being posted to the 

assessed include terrestrial docket along with this PWP. When data that are 

and aquatic organisms), anticipated to be required for registration review are 

including endangered species received, the Agency expects to be able to conduct an 

assessment for honey bees. 

Incidents Will check for For a discussion of reported ecological incidents for 

updates penoxsulam, seepage 19 of the EFED PRA. 

Human Health1 

Dietary 

Food N The most recent dietary risk assessment is adequate to 

support registration review. 

Drinking water y New uses will warrant a new drinking water 

assessment, and findings will be addressed in the 

registration review decision-making as appropriate. 

Occupational 

Handlers (mixers, loaders, y Updated occupational handler assessments will be 

applicators) conducted to reflect all the registered uses and current 

occupational exposure policies. 

Post-application y No dermal endpoint has been identified, so no dermal 

occupational post-application assessment is planned. 

If the Agency's volatilization screening tool or data 

from the Agricultural Reentry Task Force indicate 

that analyses of occupational post-application 

inhalation exposures are needed, they will be included 

in the registration review risk assessment for 

penoxsulam. 

8 
Type of Risk Assessment Conduct? Notes 

Residential 

Handlers y No short-term dermal endpoint has been identified, so 

a quantitative dern1al residential handler exposure 

assessment is not planned. Residential inhalation 

handler exposures were previously assessed, and are 

not of concern. The Agency will conduct a residential 

handler assessment for the aquatic use; however, no 

risks of concern are anticipated. 

Post-application y The Agency previously conducted residential postapplication assessments for the turf and aquatic uses. 

The risk estimates were not of concern. However, 

during registration review, these assessments will be 

updated as needed based on revised inputs, 

assumptions, and SOPs. The Agency also will 

consider the potential for residential post-application 

exposure through spray drift and volatilization. 

Other 

Aggregate y HED will conduct a new aggregate risk assessment 

that will be based on any policy changes and potential 

updates to points of departure. 

Cumulative N Penoxsulam is not a member of a cumulative group 

with a common mechanism of toxicity to humans. 

Therefore no cumulative risk assessment is planned. 

Tolerances N Per the Scoping Document, the Agency expects to 

revise the tolerance expression for penoxsulam at 40 

CFR § 180.605. 

Incidents Will check for For a discussion of reported human incidents for 

updates penoxsulam, see page 11 of the Scoping Document 

and Penoxsulam: Tier I Review of Human Incidents. 

Based on the low frequency and low severity of 

incident cases reported for penoxsulam, there does not 

appear to be a concern at this time that would warrant 

further investigation. The Agency will continue to 

monitor incident information. 

Guidance for Commenters: Additional ecological information requested for this 

registration review, and of particular interest to EPA, is described below. 

• Ecological incidents (non-target plant damage and avian, fish, reptilian, amphibian and 

mammalian mortalities) not already reported to the Agency. 

• Water quality monitoring data (see Appendix for further details). 

9 
TIMELINE 

EPA has created the following estimated timeline for the completion of the penoxsulam 

registration review in Table 5 below. 

Table 5: Projected Penoxsulam Registration Review Timeline 

Activities Estimated Date 

Opening the Docket 

Open Docket and 60-day Public Comment Period 20 IS-September 

Close Public Comment 2015-November 

Case Development 

Final Work Plan 20 16-February 

Issue DCI 2016 April-June 

Data Submission 2018 April-June 

60-day Public Comment Period for Draft Risk Assessments

4 201 9 October-December 

Registration Review Decision 

60-day Public Comment Period for Proposed Registration Review 2020 July-September 

Decision 

Registration Review Decision and Begin Post-Decision Follow-up 2021 January-March 

Total (years) 6 

NEXT STEPS 

After the 60-day public comment period on the PWP, the Seeping Document, and the 

preliminary ecological risk assessment closes, the Agency will review and respond to any 

comments received in a timely manner and then issue a Final Work Plan for the registration 

review of penoxsulam. 

4 The regulations goveming Registration Review generally require the Agency to provide a public comment period 

of at least 30 calendar days for draft risk assessments; see 40 CFR Part 155.53(c). For conventional pesticides, the 

Agency plans to provide a 60 calendar day public comment period generally for draft risk assessments. 

10 
Appendix - Additional Areas Considered in the Penoxsulam Registration 

Review 

PUBLIC COMMENTS AND FEEDBACK: 

Guidance for Commenters: The areas below highlight topics of special interest to the Agency 

where your comments, data submissions, or reference to sources of additional information could 

be of particular use. 

Trade Irritants: 

Through the registration review process, the Agency intends to solicit information on trade 

irritants and, to the extent feasible, take steps toward facilitating irritant resolution. The Agency 

will work to hannonize tolerances and international maximum residue limits (MRLs) and may 

modify tolerance levels to do so, when possible. Growers and other stakeholders are asked to 

comment on any trade irritant issues resulting from lack ofMRLs or disparities between U.S. 

tolerances and MRLs in key export markets, providing as much specificity as possible regarding 

the nature of the concern. 

Water Quality: 

Penoxsulam is not identified as a cause of impairment for any water bodies listed as impaired 

under section 303(d) of the Clean Water Act. 5 In addition, no Total Maximum Daily Loads 

(TMDL) have been developed for penoxsulam.6 More information on impaired water bodies and 

TMDLs can be found at the Agency's website. 7 The Agency invites submission of water 

quality data for this pesticide. To the extent possible, data should conform to the quality 

standards in Appendix A of the OPP Standard Operating Procedure: Inclusion of Impaired 

Water Body and Other Water Quality Data in OPP's Registration Review Risk Assessment and 

Management Process8 in order to ensure they can be used quantitatively or qualitatively in 

pesticide risk assessments. 

Environmental Justice: 

EPA seeks to achieve environmental justice, the fair treatment and meaningful involvement of all 

people, regardless of race, color, national origin, or income, in the development, implementation, 

and enforcement of environmental laws, regulations, and policies. To help address potential 

environmental justice issues, the Agency seeks information on any groups or segments of the 

population who, as a result of their location, cultural practices, or other factors, may have 

atypical, unusually high exposure to penoxsulam compared to the general population. Please 

comment if you are aware of any sub-populations that may have atypical, unusually high 

exposure compared to the general population. 

5 http://iaspub.epa.gov/tmdl waters I 0/attains nation cy.cause detail 303d?p cause group id=885 

6http://iaspub.epa.gov/tmdl waters I 0/attains nation.tmdl pollutant detail?p pollutant group id=885&p pollutant 

group name=PESTICIDES 7 http://www.epa.gov/owow/tmdll 

8 http://www.epa.gov/oppsrrd !/registration review/water quality sop.htm 

11 
ENDANGERED SPECIES: 

Consistent with EPA's responsibility under the Endangered Species Act (ESA), the Agency will 

evaluate risks to federally listed threatened and endangered (listed) species from registered uses 

of pesticides in accordance with the Joint Interim Approaches developed to implement the 

recommendations of the April 2013 National Academy of Sciences (NAS) report, Assessing 

Risks to Endangered and Threatened Species from Pesticides. The NAS report outlines 

recommendations on specific scientific and technical issues related to the development of 

pesticide risk assessments that EPA and the Services must conduct in connection with their 

obligations under the ESA and FIFRA. EPA will address concerns specific to penoxsulam in 

connection with the development of its final registration review decision for penoxsulam. 

In November 2013, EPA, the U.S. Fish and Wildlife Service, National Marine Fisheries (the 

Services), and USDA released a white paper containing a summary of their joint Interim 

Approaches for assessing risks to listed species from pesticides. These Interim Approaches were 

developed jointly by the agencies in response to the NAS recommendations, and reflect a 

common approach to risk assessment shared by the agencies as a way of addressing scientific 

differences between the EPA and the Services. Details of the joint Interim Approaches are 

contained in the November 1, 2013 white paper, Interim Approaches for National-Level 

Pesticide Endangered Species Act Assessments Based on the Recommendations of the National 

Academy of Sciences April 2013 Report. 

Given that the agencies are continuing to develop and work toward implementation of the 

Interim Approaches to assess the potential risks of pesticides to listed species and their 

designated critical habitat, this ecological problem formulation supporting the Preliminary Work 

Plan for penoxsulam does not describe the specific ESA analysis, including effects 

determinations for specific listed species or designated critical habitat, to be conducted during 

registration review. While the agencies continue to develop a common method for ESA analysis, 

the planned risk assessment for the registration review of penoxsulam will describe the level of 

ESA analysis completed for this particular registration review case. This assessment will allow 

EPA to focus its future evaluations on the types of species where the potential for effects exists, 

once the scientific methods being developed by the agencies have been fully vetted. Once the 

agencies have fully developed and implemented the scientific methods necessary to complete 

risk assessments for listed species and their designated critical habitats, these methods will be 

applied to subsequent analyses of penoxsulam as part of completing this registration review. 

ENDOCRINE DISRUPTOR SCREENING PROGRAM: 

As required by FIFRA and FFDCA, EPA reviews numerous studies to assess potential adverse 

outcomes from exposure to chemicals. Collectively, these studies include acute, subchronic and 

chronic toxicity, including assessments of carcinogenicity, neurotoxicity, developmental, 

reproductive, and general or systemic toxicity. These studies include endpoints which may be 

susceptible to endocrine influence, including effects on endocrine target organ histopathology, 

organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, 

and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and 

chronic studies that assess growth, developmental and reproductive effects in different 

12 
taxonomic groups. As part of its reregistration decision for penoxsulam, EPA reviewed these 

data and selected the most sensitive endpoints for relevant risk assessment scenarios from the 

existing hazard database. However, as required by FFDCA section 408(p), penoxsulam is 

subject to the endocrine screening part of the Endocrine Disruptor Screening Program (EDSP). 

EPA has developed the EDSP to determine whether certain substances (including pesticide 

active and other ingredients) may have an effect in humans or wildlife similar to an effect 

produced by a "naturally occurring estrogen, or other such endocrine effects as the Administrator 

may designate." The EDSP employs a two-tiered approach to making the statutorily required 

determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a 

chemical substance to interact with the estrogen, androgen, or thyroid (E, A, or T) hormonal 

systems. Chemicals that go through Tier 1 screening and are found to have the potential to 

interact with E, A, or T ho1monal systems will proceed to the next stage of the EDSP where EPA 

will determine which, if any, of the Tier 2 tests are necessary based on the avail able data. Tier 2 

testing is designed to identify any adverse endocrine-related effects caused by the substance, and 

establish a dose-response relationship between the dose and theE, A, or T effect. 

Under FFDCA section 408(p), the Agency must screen all pesticide chemicals. Between 

October 2009 and February 20 I 0, EPA issued test orders/data call-ins for the first group of 67 

chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. A second list 

of chemicals identified for EDSP screening was published on June 14, 2013 and includes some 

pesticides scheduled for registration review and chemicals found in water. Neither of these lists 

should be construed as a list of known or likely endocrine disrupters. Penoxsulam is not included 

either list. 

For further information on the status of the EDSP, the policies and procedures, the lists of 

chemicals, future lists, the test guidelines and the Tier 1 screening battery, please visit our 

website.9 

HUMAN STUDIES: 

Occupational 

Past penoxsulam risk assessments rely in part on data from studies in which adult human 

subjects were intentionally exposed to a pesticide to determine their dermal and inhalation 

exposure. Many such studies, involving exposure to many different pesticides, comprise generic 

pesticide exposure databases such as the Pesticide Handlers Exposure Database (PHED) and the 

Agricultural Reentry Task Force (ARTF) Database. EPA has reviewed all the studies supporting 

these multi-pesticide generic exposure databases, and has found no clear and convincing 

evidence that the conduct of any of them was either fundamentally unethical or significantly 

deficient relative to the ethical standards prevailing at the time the research was conducted. All 

applicable requirements of EPA's Rule for the Protection ofHuman Subjects ofResearch (40 

CFR Part 26) have been satisfied, and there is no regulatory barrier to continued reliance on 

these studies. 

9 http://www.epa.gov/endo/ 

13