Docket Number EPA-HQ-OPP-2015-0770 

www.regulations.gov 

Difethialone Preliminary Work Plan 

Registration Review: Initial Docket 

Case Number 7603 

March 2016 

Approved by: 

Director 

Pesticide Re-evaluation Division 

Date: 

Difethialone Preliminary Work Plan -Table of Contents 

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

ANTICIPATED DATA NEEDS ..................................................................................... ............... 5 

STATUTORY AND REGULATORY AUTHORITY .......... ........ ................................................. 6 

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

USE AND USAGE INFORMATION ... .... .... ......... .... ................ ........ ............................................ 7 

RECENT ACTIONS ....................................................................................................................... 8 

ANTICIPATED RISK ASSESSMENTS FOR REGISTRATION REVIEW ................................ 8 

TIMELINE ........................................... ..................... ........ .... ........................................................ 11 

NEXT STEPS ........................... .... ............ .... ................................. .... ....... ... ................................. 12 

Appendix - Additional Areas Considered in the Difethialone Registration Review ............... 13 

References: 

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

based on the following documents: 

1. Problem Formulation for Registration Review of Difethialone. Jose Melendez and Brian 

Montague. March 9, 2016. 

2. Difethialone. Human Health Scoping Document in Support of Registration Review. 

Margarita Collantes and Jaime D'Agostino. March 15, 2016. 

3. Rodenticide: Tier I (Scoping) Review of Human Incidents and Epidemiology Assessment. 

Shanna Recore. November 24, 2015. 

4. BEAD Chemical Profile for Registration Review of the Second Generation Anticoagulant 

Rodenlicides. Colwell Cook and Elizabeth Hill. February 23, 2016. 

5. Label Data Report. April 7, 2015. 

2 
6. HED Master Label Report. April 7. 2015 

7. EFED Table 1 Report. April 7, 2015 

8. Summary of Hazard and Science Pol icy Council (HASPOC) Meeting on October 1, 2015: 

Recommendations on Data Requirements for Rodenticides. Uma Habiba. December 15, 

2015. 

These and other supporting documents for the difethialone Registration Review case may be 

found in the docket EPA-HQ-OPP-2015-0770 at http://www.regulations.gov. 

3 
OVERVIEW 

The docket for difethialone (EPA-HQ-OPP-2015-0770) is now open, initiating the first public 

comment period for this Registration Review. Difethialone is a second generation anticoagulant 

rodenticide (SGAR) which inhibits coagulation, resulting in bleeding and eventual death in target 

pests, such as rats and mice. There are no registered food or agricultural uses, and difethialone 

products are intended for occupational/professional use only. 

This Preliminary Work Plan (PWP) document explains what EP A's Office of Pesticide Programs 

knows about difethialone, 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 difethialone. 

The Registration Review process was designed to include a public participation component to 

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

docket, to inform the public of what it knows about difethialone, and what types of new data or 

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

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

Appendix, and to provide comments and additional infonnation 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 info1mation. Interested stakeholders could include: 

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

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

public at large. 

The PWP begins by listing the anticipated data needs for difethialone. Next, it discusses the 

statutory and regulatory authority for Registration Review. Then the document provides 

chemical facts, use and usage information, recent actions, the anticipated risk assessments, and a 

projected Registration Review timeline for difethialone. 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 I below summarizes anticipated data needs for difethialone. For additional discussion of 

the anticipated data needs, see: Problem Formulation/or Registration Review of Difethialone, 

and Difethialone. Human Health Scoping Document in Support of Registration Review. 

Table 1: Anticipated Data Needs for the Difethialone Registration Review 

Estimated 

Guideline Timeframe 

Number1 Study Title 

Test Material (Months from 

receipt of DCI) 

850.2100 Avian acute oral toxicity (passerine species) 2 TGAI 24 

850.2300 A vi an reproduction (upland game species) TOAi 12 

850.2300 A vi an reproduction (waterfowl species) TOAi 12 

870.3200 21128-day dermal toxicity TOAI 24 

870.3465 90-day inhalation study3 TO Al 24 

TGAI = technical grade active ingredient 

1 On June 27, 2012, EPA announced certain revisions in harmonized guideline series 850 - Ecological Effects Tests 

- including renumbering and other designations or changes for some guideline studies. See "Final Test 

Guidelines; OCSPP 850 Series; Notice of Availability" 77 FR 38282, June 27, 20 12. 

http://www.regulations.gov/# ! documentDetail; D=EPA-HO-OPPT-2009-0154-0028 

2 The observation period should be extended beyond that ofa standard 850.2100 study (14 days) given that effects 

from difethialone poisoning are not immediate (i.e., it should be long enough to capture effects of difethialone 

poisoning and continue until evidence oftoxiciry has subsided) 3 Due to the expected short-term nature of occupational and commercial exposure, a short-term inhalation study 

(2 1/28-day inhalation study) wou ld be acceptable. 

5 
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.4 

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 

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 difethialone. 

CHEMICAL FACTS 

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

Table 2: Chemical Facts for Difethialone 

PC code 128967 

Case Number 7603 

CAS Number 104653-34-1 

Year first registered 1995 

Pesticide Type Rodenticide 

Chemical class SGAR 

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

Decision (RED) not subject to reregistration. However it was included in the Risk 

Mitigation Decision for Ten Rodenticides (May 2008). 

Tolerance Reassessment Not applicable 

Eligibility Decision 

(TRED) 

Cumulative group Not applicable 

4 http://www2.epa.gov/pesticide-reevaluation 

6 
Table 2: Chemical Facts for Difethialone 

40 CFR Citation There are no established tolerances for difethialone. 

Dual-use Difethialone 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 difethialone. 

Pesticide Re-evaluation Nicole Zinn, zinn.nicole@epa.gov, (703) 308-7076 

Division, Chemical 

Review Manager 

Registration Division, Marianne Lewis, lewis.marianne@epa.gov, 703-308-8043 

Product Manager 

USE AND USAGE INFORMATION 

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

Chemical Profile for Registration Review of the Second Generation Anticoagulant Rodenticides 

in the Registration Review docket for more details. 

Table 3: Difethialone Use and Usage Information 

Summary of Use Difethialone is a SGAR, developed as a result of rodents 

developing resistance to warfarin and other first-generation 

anticoagulants. It is registered for the control of commensal 

rodents and works by interfering with the blood clotting 

mechanism. The primary use site for difethialone is in and near 

human habitats. Products must be in locations out of reach of 

children, pets, domestic animals, and non-target wildlife or in 

tamper-resistant bait stations. Bait stations are mandatory in 

outdoor above-ground use. 

Use Sites Difethialone is registered for use in and around 

agricultural/industrial/commercial/residential buildings, transport 

vehicles (ships, trains, and aircraft), food processing handling and 

storage areas, around refuse/solid waste containers, and in sewers. 

Difethialone products require bait stations for all outdoor and 

above-ground placements and for indoor placements where 

children, wildlife or domestic animals may be exposed, and 

restrict application to within 50 to 100 feet of man-made 

structures. Burrow baiting is prohibited. 

Summary of Usage Specific data on difethialone usage are not available. 

Formulation Type(s) Difethialone is formulated as pellets, ready-to-use (RTU) place 

packs, blocks, mini-blocks, meal, and paste. 

Application Method(s) Consumer-use products containing difethialone are prohibited. 

Professional/commercial uses of SGARs require bait stations for 

all outdoor and above-ground placements and for indoor 

placements where children, wildlife or domestic animals may be 

exposed. Furthermore, labels prohibit broadcast application. 

Technical Registrant(s) Liphatech Inc. 

7 
Table 3: Difethialone Use and Usage Information 

No. of Registrations I 14 Section 3 products5 and 1 Section 24c products 

Restricted Use I No 

Guidance for Commenters: Additional areas of use and usage related information 

requested for this Registration Review, and of particular interest to EPA, are described 

below. 

• Information about preferences of applicators and what drives the selection of one SGAR 

over another, along with more details on when and why these SGARs are used would be 

helpful for future assessments. 

• Use distribution (e.g. , acreage and geographical distribution ofrelevant use sites). 

• Median and 901

h percentile reported use rates (pounds active ingredient per acre) from 

usage data - national, state, and county. 

• Typical application timing (date of first application and application intervals) - national, 

state, and county. 

• Usage/use information. 

• State or local use restrictions. 

• Foreign technical registrants not listed above who supply technical difethialone to the 

U.S. market. 

RECENT ACTIONS 

In May 2008, the Agency issued the Risk Mitigation Decision for Ten Rodenticides, which 

included difethialone. This final risk mitigation decision included components to minimize 

children's exposure to rodenticide products used in homes, and to reduce wildlife exposures and 

ecological risks. More information on the 2008 decision case may be found in the docket EPAHQ-OPP- 2006-0955 at http://www.regulations.gov. 

ANTICIPATED RISK ASSESSMENTS FOR REGISTRATION REVIEW 

The most recent human health assessment for difethialone was completed in 2008 for a proposed 

use on commensal rodents. In this 2008 assessment, occupational exposures were not quantified 

because the new product's formulation and use pattern were the same as a currently registered 

product. The most recent ecological and environmental fate risk assessment conducted for 

difethialone is the endangered species assessment for the risks of difethialone to the federally 

threatened Alameda whipsnake, and the federally endangered salt marsh harvest mouse and San 

Joaquin kit fox, which was issued in March 2012. Findings and conclusions from these risk 

assessments are summarized in the Difethialone: Preliminary Problem Formulation/or 

Environmental Fate, Ecological Risk, Endangered Species, and Drinking Water Exposure 

Assessments in Support o/Registration Review, and Difethialone. Human Health Scoping 

Document in Support of Registration Review. 

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

(http://oaspub.epa.gov/pestlabl/ppls.home). 

8 
During Registration Review, the Agency anticipates the need to conduct a comprehensive 

ecological risk assessment, including an endangered species assessment, for all registered uses of 

difethialone. For human health, EPA anticipates the need to conduct an occupational handler 

risk assessment during Registration Review. If toxicological endpoints or points of departure are 

revised based on the data that are anticipated to be required for Registration Review, they will be 

considered in the new assessments, as well as any changes to the standard operating procedures 

or default exposure assumptions. 

Table 4 summarizes the anticipated Registration Review risk assessments based on Problem 

Formulation for Registration Review of Difethialone, and Difethialone. Human Health Scoping 

Document in Support of Registration Review. 

9 
Table 4: Anticipated Risk Assessments for the Difethialone Registration Review 

Type of Risk Assessment Conduct? Notes 

Ecoloe:ical and Environmental Fate 

Comprehensive ecological, y The potential for aquatic exposure is assumed to be 

including endangered species negligible based on the use pattern; therefore, EPA 

does not anticipate conducting an aquatic risk 

assessment. 

Exposures of honey bees to difethialone residues are 

not expected since they are unlikely to feed on bait 

blocks and residues are not expected to be present in 

pollen and nectar. Therefore, EPA is not requesting 

the full suite of pollinator protection studies as 

outlined in recent guidance6, at this time. 

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

updates difethialone, see page 15 of the Problem Formulation. 

Human Health 

Dietary 

Food N The registered use patterns for difethialone are not 

expected to result in dietary exposures from surface or 

ground drinking water, as all end-use products prohibit 

broadcasting difethialone or applying products directly to 

food or feed crops. 

Drinking water N See above 

Occupational 

Handlers (mixers, loaders, y Short-term dermal and inhalation occupational 

applicators) handler exposure assessments are expected during 

Registration Review based on the potential exposure 

to handlers during the application of difethialone. 

Post-application N All post-application activities for difethialone include 

the requirement for personal protective equipment 

that limits post-application exposure. 

Residential 

Handlers N Consumer-based products for difethialone are 

prohibited. Therefore, residential exposures are not 

expected. 

Post-application N See (residential handlers) above 

Other 

Aggregate N An aggregate risk assessment evaluates the combined 

risk from dietary and residential exposures. However, 

based on the difethialone use pattern, no dietary (food 

or drinking water) or residential exposures are 

expected. 

Cumulative N EPA has not made a common mechanism of toxicity 

finding as to difethialone and any other substances. 

10 
Tolerances N All uses of difethialone are classified as non-food 

uses; therefore, no tolerances are established. 

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

updates difethialone, see the Rodenticide: Tier I (Scoping) 

Review of Human Incidents and Epidemiology 

Assessment. 

Guidance for Commenters: Additional ecological information requested for this 

Registration Review, and of particular interest to EPA, is described below. 

• Information on the amount of product or active ingredient that may be applied per unit 

area, the number of applications that can be made per unit time, and the minimum 

interval between applications. 

• Non-guideline data on toxicity to terrestrial invertebrates other than the honeybee may be 

useful for reducing uncertainty in the risk assessment. 

• Ecological incidents (avian, reptilian, amphibian and mammalian mortalities) not already 

reported to the Agency. 

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

Guidance for Commenters: Additional human health information requested for this 

Registration Review, and of particular interest to EPA, is described below. 

• For bulk pelleted and meal baits, labels lack sufficient information on the appropriate 

methods and containers that may be used to measure the label specified amount of bait 

per refillable station. Information on the specific methods and amounts is requested. 

• Labels lack directions to specify a maximum number of refillable mouse and/or rat bait 

stations to be used for perimeter treatments of agricultural or commercial buildings. 

Information on maximum amounts applied or information on the amount of product that 

may be handled on a given day by each occupational user is requested. 

TIMELINE 

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

Registration Review in Table 5 below. 

Table 5: Projected Difetbialone Registration Review Timeline 

Activities Estimated Date 

Opening the Docket 

Open Docket and 60-day Public Comment Period 2016 - March - completed 

Close Public Comment 2016 - May 

Case Development 

Final Work Plan (FWP) 2016 - September 

Issue DCI 2016 October - December 

Data Submission 2018 October - December 

6 https://www.epa.gov/pollinator-protection/pollinator-risk-assessment-guidance 

11 
Table 5: Projected Difethialone Registration Review Timeline 

Activities Estimated Date 

60-day Public Comment Period for Draft Risk 2020 April - June 

Assessments 7 

Registration Review Decision 

60-day Public Comment Period for Proposed Interim 2021 January - March 

Registration Review Decision 

Interim Registration Review Decision and Begin Post- 2021 

Decision Follow-up 

Total (years) 6 

NEXT STEPS 

After the 60-day public comment period closes, the Agency will review and respond to any 

comments received in a timely manner and then issue a FWP for the Registration Review of 

difethialone. 

7 The regulations governing 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 l 55.53(c). For conventional pesticides, the 

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

12 
Appendix - Additional Areas Considered in the Difethialone 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 harmonize 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. Because difethialone is not registered for food/feed uses in the U.S., it 

has no U.S. tolerances; therefore, the Agency does not anticipate any trade irritant issues for it. 

Water Quality: 

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

under section 303(d) of the Clean Water Act.8 In addition, no Total Maximum Daily Loads 

(TMDL) have been developed for difethialone.9 More information on impaired water bodies and 

TMDLs can be found at the Agency's website. 10 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 

Process11 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 difethialone compared to the general population. Please 

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

9http://iaspub.epa.gov/tmdl waters IO/attains nation.tmdl pollutant detail?p pollutant group id=885&p pollutant 

group name=PESTICIDES 1

0 http://www.epa.gov/owow/tmdl/ 11 http://www2.epa.gov/pesticide-reevaluation/opp-guidance-submission-state-and-tribal-water-quality-monitoringdata 

13 
comment if you are aware of any sub-populations that may have atypical, unusually high 

exposure compared to the general population. 

ENDANGERED SPECIES: 

A risk assessment that supports a complete endangered species determination has not been 

conducted for difethialone. The ecological risk assessment planned during Registration Review 

will allow the Agency to determine whether use of difethialone has "no effect" or "may affect" 

federally listed threatened or endangered species (listed species) or their designated critical 

habitats. When an assessment concludes that a pesticide's use "may affect" a listed species or its 

designated critical habitat, the Agency will consult with the U.S. Fish and Wildlife Service 

(FWS) and/or National Marine Fisheries Service (NMFS) (together, the Services), as 

appropriate. 

A previous endangered species assessment was conducted for difethialone in 2012, for the risks 

of difethialone to the federally threatened Alameda whipsnake, and the federally endangered salt 

marsh harvest mouse and San Joaquin kit fox. The assessment resulted in a determination that 

the use of difethialone "may affect" and is "likely to adversely affect" the subject species. As a 

result, the Agency requested initiation of formal consultation with the FWS. 

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 

taxonomic groups. As part of its reregistration decision for difethialone, 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 ), difethialone 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 hormonal 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 available 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 the E, A, or T effect. 

14 
Under FFDCA section 408(p), the Agency must screen all pesticide chemicals. Between 

October 2009 and February 2010, 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 12 and includes some 

pesticides scheduled for Registration Review and chemicals found in water. Difethialone is not 

on either list. Neither of these lists should be construed as a list of known or likely endocrine 

disruptors. 

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.'3 

HUMAN STUDIES: 

Occupational and Residential 

The risk assessments EPA anticipates conducting during Registration Review will 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), the Agricultural Reentry Task Force (ARTF) Database, 

and the Outdoor Residential Exposure Task Force (ORETF) 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 of Human Subjects of 

Research ( 40 CFR Part 26) have been satisfied, and there is no regulatory barrier to continued 

reliance on these studies. 

12 See http://www.regulations.gov/#!documentDetail;D=EPA-HO-OPPT-2009-0477-0074 for the final second list of 

chemicals. 13 http://www2.epa.gov/endocrine-disruption 

15