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Alpha-chlorohydrin– Table of Contents

INTRODUCTION .......................................................................................................................... 4

ALPHA-CHLOROHYDRIN CHEMICAL FACTS ...................................................................... 6

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

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

SCIENTIFIC ASSESSMENTS ...................................................................................................... 7

A. Human Health Assessment............................................................................................... 7

Hazard Characterization ........................................................................................................ 7

Dietary Exposure and Risk Assessment .................................................................................. 7

Food Tolerances ..................................................................................................................... 7

Human Health Incidents......................................................................................................... 8

B. Environmental Assessment .............................................................................................. 8

Ecological Risk Characterization........................................................................................... 8

Threatened and Endangered Species...................................................................................... 8

Ecological Incidents................................................................................................................ 9

C. Endocrine Disruptor Screening Program ......................................................................... 9

COMBINED WORK PLAN, SUMMARY DOCUMENT, AND PROPOSED INTERIM 

REGISTRATION REVIEW DECISION ..................................................................................... 10

NEXT STEPS AND TIMELINE.................................................................................................. 11

References:

This Combined Work Plan, Summary Document, and Proposed Interim Registration Review 

Decision summarizes the Environmental Protection Agency's current position based on the 

following documents:

1. EFED Registration Review Problem Formulation for Alpha-Chlorohydrin. Federoff, N.E.; 

Lin, James. October 21, 2015.

2. Alpha-Chlorohydrin. Human Health Assessment Scoping Document and Draft Human 

Health Risk Assessment in Support of Registration Review. Bloem, Thomas; Godshall, 

Joshua; Perron, Monique M. September 29, 2015.

3. BEAD Chemical Profile (BCP) for Registration Review: Alpha-Chlorohydrin (PC

Code 117101). Cook, Colwell; Hill, Elizabeth. May 21, 2015.

4. Alpha-chlorohydrin: Tier I (Scoping) Review of Human Incidents and Epidemiology. 

Evans, Elizabeth; Recore, Shanna. August 13, 2015.
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These and other supporting documents for the alpha-chlorohydrin registration review case may 

be found in the docket EPA-HQ-OPP-2015-0726 at http://www.regulations.gov.
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INTRODUCTION

The docket for alpha-chlorohydrin is now open, initiating the first public comment period for this 

registration review (docket number EPA-HQ-OPP-2015-0726). This document is the 

Environmental Protection Agency’s (EPA or the Agency) Combined Work Plan, Summary 

Document, and Proposed Interim Registration Review Decision for alpha-chlorohydrin. It is 

being issued pursuant to 40 CFR Sections 155.50, 155.56, and 155.58. This document explains 

what EPA’s Office of Pesticide Programs knows about alpha-chlorohydrin, highlighting 

anticipated data and assessment needs and providing an anticipated timeline for completing 

alpha-chlorohydrin review. 

This document includes the Agency’s Proposed Interim Registration Review Decision for alphachlorohydrin. A registration review decision is the Agency's determination whether a pesticide 

meets, or does not meet, the standard for registration in the Federal Insecticide, Fungicide, and 

Rodenticide Act (FIFRA). The Agency may issue, when it determines it to be appropriate, 

Interim Registration Review Decision before completing a registration review. Among other 

things, the Interim Registration Review Decision may: 1) require new risk mitigation measures; 

2) impose interim risk mitigation measures; 3) identify additional data or other information 

required to complete the review; and 4) include schedules for submitting the required data, 

conducting the new risk assessment, and completing the registration review. For further 

information on alpha-chlorohydrin, additional documents can be found in EPA’s public docket 

(EPA-HQ-OPP-2015-0726) at www.regulations.gov.

EPA is issuing a Proposed Interim Registration Review Decision for alpha-chlorohydrin so that 

it can (1) move forward with aspects of the registration review decision that are complete and (2) 

implement interim risk mitigation. The Agency is currently working with the U.S. Fish and 

Wildlife Service and the National Marine Fisheries Service to develop methodologies for 

conducting national endangered species assessments for pesticides. Therefore, although EPA 

has not yet fully evaluated risks to threatened and endangered species, the Agency will complete 

its endangered species assessment and any necessary consultation with the Services for alphachlorohydrin prior to completing the alpha-chlorohydrin registration review. Likewise, the 

Agency will complete endocrine screening for alpha-chlorohydrin, pursuant to the Federal Food, 

Drug, and Cosmetic Act (FFDCA) section 408(p), before completing this registration review. 

Last, EPA will determine whether additional pollinator exposure and effects data are necessary 

to make a final registration review decision for alpha-chlorohydrin and issue a data call-in (DCI) 

to obtain any such data prior to completing the alpha-chlorohydrin registration review.

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 alpha-chlorohydrin and what types of new 

data or other information would be helpful for the Agency to receive as it moves toward a 

decision on alpha-chlorohydrin. The Agency encourages all interested stakeholders to review 

the Combined Work Plan, Summary Document, and Proposed Interim Registration Review 

Decision to provide comments and additional information that will help the Agency’s decisionmaking process for this chemical. In addition to general areas on which persons may wish to 

comment, there are some areas identified in the Combined Work Plan, Summary Document, and 

Proposed Interim Registration Review Decision and Appendix about which the Agency 
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specifically seeks comments and information. 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 only registered use for alpha-chlorohydrin is as a tamper-proof bait station/bait application 

delivery system for elimination of Norway rats. One product (Epibloc® Rodenticide, produced 

by Gametrics, Ltd.) is currently registered containing alpha-chlorohydrin, which is classified as a 

restricted use pesticide (RUP), for retail sale to and use only by certified applicators or persons 

under their direct supervision. Alpha-chlorohydrin is approved for use in and around the indoors 

of commercial/industrial facilities and sanitary sewers, the label states not to use the product in 

any facility where children may be present, and there are no outdoor uses permitted. 

STATUTORY AND REGULATORY AUTHORITY

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

pesticides distributed or sold in the U.S. generally must be registered by EPA, 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 at www.epa.gov/pesticide-reevaluation/registrationreview-process.

The Agency is implementing the registration review program pursuant to Section 3(g) of 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.
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ALPHA-CHLOROHYDRIN CHEMICAL FACTS

Table 1 provides a summary of the chemical facts for alpha-chlorohydrin.

Table 1: Chemical Facts for alpha-chlorohydrin

PC code 117101

Case Number 4120

CAS Number 96-24-2

Year first registered Alpha-chlorohydrin was originally registered in 1983 and 

cancelled in 1991 due to maintenance fee non-payment. It was 

newly registered in 2006. 

Pesticide Type Rodenticide 

Chemical class Not Applicable 

Reregistration Eligibility 

Decision (RED)

The current alpha-chlorohydrin registration was registered after 

November 1984, therefore it was not subject to reregistration.

Tolerance Reassessment 

Eligibility Decision 

(TRED)

Not applicable. There are no food uses for alpha-chlorohydrin

Cumulative group Unlike other pesticides for which EPA has followed a cumulative 

risk approach based on a common mechanism of toxicity, EPA 

has not made a common mechanism of toxicity finding with 

alpha-chlorohydrin. Alpha-chlorohydrin does not appear to 

produce a toxic metabolite produced by other substances.

40 CFR Citation There are no established tolerances for alpha-chlorohydrin.

Dual-use Alpha-chlorohydrin 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 alpha-chlorohydrin.

Pesticide Re-evaluation 

Division, Chemical 

Review Manager

Matthew Manupella, manupella.matthew@epa.gov, (703) 347-

0411

Registration Division, 

Product Manager

Mark Suarez, suarez.mark@epa.gov, (703) 305-0120

USE AND USAGE INFORMATION

Table 2 summarizes the use and usage information for alpha-chlorohydrin. Please see the BEAD 

Chemical Profile (BCP) for Registration Review: Alpha-Chlorohydrin in the registration review 

docket for more details.

Table 2: Alpha-chlorohydrin Use and Usage Information

Summary of Use Alpha-chlorohydrin is a rodenticide that causes male infertility in 

male mammals at low doses. At high doses testicular lesions and 

/or death can occur. 
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Table 2: Alpha-chlorohydrin Use and Usage Information

Use Sites The alpha-chlorohydrin product is used in sanitary sewers and

inside industrial and commercial facilities.

Summary of Usage This product has not been manufactured nor sold in the United 

States; consequently, there are no usage data for alphachlorohydrin available.

Formulation Type(s) Pelleted/Tableted

Application Method(s) The alpha-chlorohydrin product is a rodenticide bait that can be 

applied in a sachet ("place pack") in sanitary sewers and inside 

industrial and commercial facilities for control of Norway rats.

Technical Registrant(s) Gametrics, Ltd

No. of Registrations 1 Section 3 product1

Restricted Use Yes

RECENT ACTIONS

There have been no recent actions for alpha-chlorohydrin. 

SCIENTIFIC ASSESSMENTS

A summary of the Agency’s human health risk assessment and the problem formulation for the 

environmental fate, ecological risk, endangered species, and drinking water exposure 

assessments, Alpha-Chlorohydrin. Human Health Assessment Scoping Document and Draft 

Human Health Risk Assessment in Support of Registration Review (September 29, 2015) and

EFED Registration Review Problem Formulation for Alpha-Chlorohydrin (October 21, 2015), 

are presented below. For the detailed risk assessments, see the public docket (EPA-HQ-OPP2015-0726) accessed at www.regulations.gov.

A. Human Health Assessment

Hazard Characterization 

The toxicological database is considered adequate for characterizing hazard and assessing risk 

from alpha-chlorohydrin. No additional studies are anticipated to be needed for registration 

review.

Dietary Exposure and Risk Assessment

There are no registered food/feed uses and existing use patterns are not expected to contaminate 

surface or ground water; thus, a dietary exposure assessment was not conducted and there are no 

dietary risks of concern.

Food Tolerances

There are no U.S. tolerances established for alpha-chlorohydrin because alpha-chlorohydrin is 

not registered for any food/feed uses.

 

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

(http://oaspub.epa.gov/pestlabl/ppls.home).
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Residential and Occupational Exposure and Risk Assessment 

Residential handler and post-application exposures from alpha-chlorohydrin are expected to be 

negligible as the registered product is a RUP and not approved for use in residential settings. 

When used in above-ground bait stations, the bait formulation is confined inside tamper-resistant 

plastic bait housing. Based on the negligible exposure potential of the currently registered uses of 

alpha-chlorohydrin, no toxicological points of departure (PODs) have been established. 

Occupational handler and post-application exposures are not anticipated since the products are 

packaged in an enclosed system. Alpha-chlorohydrin is approved for use in indoor areas of 

commercial/industrial facilities and sanitary sewers, the label states not to use the product in any 

facility where children may be present, and there are no outdoor uses permitted.

EPA believes that residential and occupational exposures to the currently registered uses of 

alpha-chlorohydrin do not pose a significant human health risk. 

Human Health Incidents

A summary report listing incidents for alpha-chlorohydrin reported to the OPP Incident Data 

System (IDS) has been previously conducted on August 13, 2015. The report covers the time 

period in the U.S. from 1998 to 2015. The evaluation of incident data for alpha-chlorohydrin 

indicates no reported incidents. Therefore, at this time, there are no remarkable case reports that 

suggest a plausible association between a moderate or severe health outcome and exposure to 

alpha-chlorohydrin. The 2015 review of the incident data does not warrant further investigations 

at this time.

B. Environmental Assessment

Ecological Risk Characterization

Risk characterization is the integration of exposure and ecological effects characterization to 

determine the potential ecological risk and the likelihood of direct and indirect effects to nontarget organisms in aquatic and terrestrial habitats. In the case of alpha-chlorohydrin, risk was 

not quantitatively calculated. However, risks were qualitatively determined to not be of concern 

for non-target organisms for the following reasons: 

(1) Direct consumption of bait is unlikely to be a concern due to location of use sites (indoor 

only) and label directions and restricted use designation when used in sanitary sewers; 

(2) Secondary poisoning due to consumption of contaminated carcasses is unlikely due to rapid 

clearance of the chemical in target animals; and 

(3) Aquatic contamination is unlikely to reach levels of concern due to the bait location in the 

case of indoor uses and the low exposure potential for sanitary sewer uses based on the high 

number of sachets that would need to wash into receiving waters to be a concern; and

(4) Exposure to pollinators is unlikely due to the restricted uses of alpha-chlorohydrin. Therefore 

pollinator data will not be required. 

Threatened and 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 
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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 alpha-chlorohydrin 

in connection with the development of its final registration review decision. 

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, the ecological problem formulation supporting Combined Work Plan, 

Summary Document, and Proposed Interim Registration Review Decision for alpha-chlorohydrin 

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 alpha-chlorohydrin 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 alpha-chlorohydrin as part of completing this registration review. 

Ecological Incidents

A search was made on June 2, 2015 of the Ecological Incident Information System (EIIS, 

version 2.1) and the Incident Data System (IDS), which are maintained by the Agency’s Office 

of Pesticide Programs, and the Avian Incident Monitoring System (AIMS), which is maintained 

by the American Bird Conservancy. There were no incidents for alpha-chlorohydrin reported to 

the Agency. 

C. 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, 
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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 most recent registration decision for alpha-chlorohydrin, EPA

reviewed these data and determined that a qualitative toxicity assessment is appropriate for 

alpha-chlorohydrin. However, as required by FFDCA section 408(p), alpha-chlorohydrin 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.

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, 20132and includes some pesticides 

scheduled for Registration Review and chemicals found in water. Alpha-chlorohydrin was not 

included on 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.3

In the interim, EPA is making no human health or environmental safety findings associated with 

the EDSP screening of alpha-chlorohydrin. Before completing this Registration Review, the 

Agency will make an EDSP FFDCA section 408(p) determination.

COMBINED WORK PLAN, SUMMARY DOCUMENT, AND PROPOSED INTERIM 

REGISTRATION REVIEW DECISION

In accordance with 40 CFR Sections 155.50, 155.56, and 155.58, the Agency is issuing this 

combined Work Plan, Summary Document, and Proposed Interim Registration Review Decision. 

Except for the endangered species and EDSP components of the alpha-chlorohydrin registration 

review case, the Agency has made the following proposed interim decision: (1) no additional 

data are anticipated to be required at this time; and (2) no changes to the affected 

registrations or their labeling are needed at this time. EPA has not identified any risks of 

concern to human health. 

 

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

chemicals.

3 http://www.epa.gov/endo/
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NEXT STEPS AND TIMELINE

A Federal Register Notice will announce the availability of this combined Work Plan and 

Summary Document and Proposed Interim Registration Review Decision for alpha-chlorohydrin 

and allow a 60-day comment period. If there are no significant comments or additional 

information submitted to the docket during the comment period that leads the Agency to change 

its proposed decision, EPA may issue an Interim Registration Review Decision for alphachlorohydrin (case 4120). However, a final decision for alpha-chlorohydrin may be issued 

without having previously issued an interim decision. A final decision on the alpha-chlorohydrin 

registration review case will occur after an ESA and EDSP FFDCA section 408(p) determination 

has been made.

EPA has created the following estimated timeline for the completion of alpha-chlorohydrin 

registration review.

Table 3: Projected Alpha-chlorohydrin Registration Review Timeline

Activities Estimated Date

Opening the Docket and Combined Work Plan, Summary Document, and Proposed Interim 

Registration Review Decision

Open Public Docket and Public Comment Period for 

Combined Work Plan, Summary Document, and 

Proposed Interim Registration Review Decision 

2015 – December

Close Public Comment Period 2016 – February

Interim Registration Review Decision and Begin PostDecision Follow-up2016- June

Total (years) 0.5