Docket Number EPA-HQ-OPP-2014-0544 

www.regulations.gov 

4-chlorophenoxyacetic acid ( 4-CP A) 

Combined Work Plan, Summary Document, and Proposed Interim 

Registration Review Decision 

Case Number 2115 

August 15, 2014 

Approved by: B.~heryd P Mk'--< <j'UYt-<-.._ , ~ Richard P. Keigwin, Jr. 

Director 

Pesticide Re-evaluation Division 

Date: F; /lsj~o ;.c.f 

4-CP A- Table of Contents 

Introduction 3 

Statutory and Regulatory Authority 3 

4-CP A Chemical Facts 4 

Use and Usage Information 4 

Recent Actions 5 

Scientific Assessments 5 

Combined Work Plan, Summary Document, and Proposed Interim Registration 

Review Decision 7 

Next Steps and Timeline 8 

Appendix A- Additional Areas Considered in the 4-CP A Registration Review 8 

References: 

This document summarizes the Environmental Protection Agency's current position based on the 

following documents: 

1. EFED Preliminary Risk Assessment to Classify Registered 4-CP A Uses as De Minimus 

Risk to Listed/Non Listed Species and "No Effects" Determination. Edward Odenkirchen, 

Ph.D., Senior Science Advisor. June 5, 2014. 

2. 4-Chlorophenoxyacetic Acid. Human Health Risk Assessment in Support of Registration 

Review. Ideliz Negron-Encarnacion, Ana Rivera-Lupianez, Seyed Tadayon, Ronnie J Bever 

Jr., Ph.D. July 17, 2014. 

3. BEAD Chemical Profile for Registration Review: 4-CPA and Salts (010401). Sunil 

Ratnayake, Sepehr Haddad, and Derek Berwald. May 3, 2012. 

4. 4-Chlorophenoxyacetic Acid, and Salts: Tier I Review of Human Incidents. Shanna Recore, 

Elizabeth Evans. June 26, 2014. 

These and other supporting documents for the 4-CP A registration review case may be found in 

the docket EPA-HQ-OPP-201 4-0544 at http://www.regulations.gov. 

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INTRODUCTION 

The docket for 4-chlorophenoxyacetic acid (4-CPA) is now open (EPA-HQ-OPP-2014-

0544), initiating the first public comment period for this registration review. This document is 

the Environmental Protection Agency's (EPA or the Agency) combined Work Plan, Summary 

Document, and Proposed Interim Registration Review Decision for 4-CP A. 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 4-CP A, highlighting anticipated data and assessment 

needs and providing an anticipated timeline for completing 4-CP A review. It also includes the 

Agency's Proposed Interim Registration Review Decision for 4-CP A. In addition to general 

areas on which the public may wish to comment, the Appendix highlights topics of special 

interest to the Agency where additional information could be of particular use. 

A registration review decision is the Agency's determination whether a pesticide meets, 

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

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

proposed interim registration review decision before completing registration review. Among 

other things, the proposed interim registration review decision may require new risk mitigation 

measures, impose interim risk mitigation measures, identify data or information required to 

complete the review, and include schedules for submitting the required data, conducting the new 

risk assessment and completing registration review. 

The pesticide 4-CP A is a plant growth regulator registered for use exclusively as a soaking 

agent for mung bean sprouts in greenhouse operations to prevent root formation and, thereby, is 

intended to improve the sorting and handling of the mung bean sprouts for packaging. All of the use 

occurs indoors. 4-CP A is applied in a dilute solution of 2 to 3 mg/L of active ingredient to a water 

bath to soak batches of about 3 500 pounds of beans. Once the beans have soaked for several hours, 

they are washed to remove the surface residues, and are then germinated indoors for several days. 

After sprouting, the hulls and roots are discarded, and the remaining portion is packaged and sold for 

human consumption. 

The Reregistration Eligibility Decision document (RED) for 4-CP A was completed on March 

1, 1997. EPA reassessed 4-CP A tolerances in the 2003 TRED. For further information about 4-

CPA, additional documents can be found in EPA's public docket (EPA-HQ-OPP-2014-0544) at 

www.regulations. gov. 

STATUTORY AND REGULATORY AUTHORITY 

The Food Quality Protection Act (FQP A) 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 

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marketplace can be used safely. Information on this program is provided at 

www.epa.gov/oppsrrdl/registration review/. 

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. 

4-CPA CHEMICAL FACTS 

PC code 019401 

Case Number 2115 

CAS Number 122-83-3 

Year first registered 1969 

Pesticide Type Conventional Chemical 

Chemical class Phenoxy 

Reregistration Eligibility March 1997 

Decision (RED) ! 

Tolerance Reassessment April 4, 2003 

Eligibility Decision 

(TRED) 

Cumulative Group EPA has not made a common mechanism of toxicity finding as to 

4-CP A and any other substances, and 4-CP A does not appear to 

produce a toxic metabolite produced by other substances. 

40 CFR Citation Tolerances are established in the 40 CFR § 180.202 for residues of 

4-CP A inion mung bean sprouts at 0.2 ppm. 

Dual-use Conventional pesticidal uses only 

Non-pesticidal uses No non-pesticidal uses of 4-CP A 

Pesticide Re-evaluation Miguel Zavala, zavala.miguel@epa.gov, 703-347-0504 

Division, Chemical 

Review Manager 

Registration Division, Tony Kish, kish.tony@epa.gov, 703-308-9443 

Product Manager 

USE AND USAGE INFORMATION 

4-CP A is registered for use in the food industry as a plant growth regulator to restrict root 

growth during seed germination of mung beans. Below is a summary of the use/usage of 4-CP A. 

For more details please see BEAD Chemical Profile for Registration Review: 4-CPA and Salts 

(010401), May 3, 2012. 

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Summary of Use 4-CP A is applied to a water bath to soak mung beans. The beans 

soak for several hours, are washed, and then germinated indoors 

for several days. After sprouting, the hulls and roots are 

discarded, and the remaining portion is packaged and sold for 

human consumption. 

Use Sites Indoor use. 

Summary of Usage 10-20 lbs active ingredient are used annually nationwide 

Formulation Type(s) Amorphous powder 

Technical Registrant(s) ConAgra Foods 

No. of Registrations 1 

Restricted Use No 

RECENT ACTIONS 

There are no recent actions for 4-CP A. 

SCIENTIFIC ASSESSMENTS 

A summary of the Agency's human health and environmental fate and ecological risk 

assessments, 4-Chlorophenoxyacetic Acid. Human Health Risk Assessment in Support of 

Registration Review (July 17, 2014) and EFED Preliminary Risk Assessment to Classify 

Registered 4-CP A Uses as De Minimus Risk to Listed/Non Listed Species and "No Effects" 

Determination. (June 5, 2014) is presented below. For the detailed risk assessments, see the 4-

CPA public docket (EPA-HQ-OPP-2014-0544) at www.regulations.gov. 

Human Health Assessment 

Hazard Characterization and Risk 

The toxicological database is considered adequate for characterizing hazard and assessing 

risk from 4-CP A. No additional shtdies are anticipated to be needed for registration review. 

Dietary Exposure Assessment 

A chronic dietary (food only) exposure and risk assessment was conducted using 

tolerance-level residue values for mung bean and assuming 100% of crop treated. Drinking water 

is not an anticipated exposure pathway, as application of 4-CP A occurs indoors and the use is 

limited. The chronic dietary risk for 4-CP A was below the Agency's level of concern for the 

general population and all population subgroups. 

Food Tolerances 

A tolerance of0.2 ppm is established in the 40 CFR §180.202 for residues of4-CPA 

in/on bean, mung, sprouts. The tolerance expression currently includes measurement of residues 

of parent 4-CP A and its metabolite 4-chlorophenol. The Agency has completed an evaluation of 

the established tolerance and determined that: (1) the tolerance expression needs to be modified 

in accordance with current Agency policy for writing tolerance expressions; and, (2) to exclude 

measurement of the metabolite 4-chlorophenol because it is no longer considered a metabolite of 

risk concern. 

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Canada has established a maximum residue limit (MRL) of 2 ppm for residues of 4-CPA 

inion mung beans. EPA's 0.2 ppm tolerance is based on updated residue data that has not been 

submitted to Canada. The Agency will pursue harmonizing tolerances with Canada where 

possible during registration review. For more information please refer to 4-Chlorophenoxyacetic 

Acid. Human Health Risk Assessment in Support of Registration Review (July 17, 20 14). 

Residential and Occupational Exposure 

A residential handler and post-application exposure assessment is not needed for 

registration review because there are no registered residential uses of 4-CPA. For occupational 

use, the Agency believes that the potential for exposure to 4-CP A during pesticide handling 

operations exists, but is very low. Based on a conservative quantitative assessment of 

occupational handler exposure and risk, no risks of concern were identified. Occupational postapplication exposure was not quantitatively assessed. However, based on 4-CPA's use pattern 

and low exposure potential, the occupational handler assessment is expected to be protective of 

potential worker post-application exposure. 

Environmental Assessment 

EPA conducted a qualitative environmental fate and effects assessment for 4-CP A and 

has determined that effects to non-target species are unlikely. EPA considered potential 4-CPA 

exposure to non-target organisms, available information on the toxicity of 4-CP A from 

ecological structure activity relationships, and annual usage information. Spent mung bean 

soaking solution can be disposed of down municipal wastewater drains and represents a 

complete exposure pathway to downstream receiving waters. However, there is a low likelihood 

for significant toxicity to aquatic organisms, the taxa most likely to be exposed via a wastewater 

discharge scenario, based on predictions from ecological structure activity relationships. In 

addition, the 20 pounds of 4-CP A used annually is expected to be geographically disperse and 

greatly diluted before reaching receiving waters. 

Threatened and Endangered Species 

Based on the type and extent of use, the low expected toxicity predicted by quantitative 

structure activity relationships, and the highly diffuse nature of the use site coupled with extremely 

low annual usage, the Agency concludes that effects on the environment are not reasonably expected 

to occur from the registered use of 4-CP A. Therefore, the EPA anticipates making a "no effects" 

determination under the Endangered Species Act (ESA) for all listed species and no adverse 

modification of designated critical habitat for such species is expected from the registered use of 4-

CPA. 

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 most recent registration decision for 4-CP A, EPA 

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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 ), 4-

CP A 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, 2013 1 and includes some 

pesticides scheduled for Registration Review and chemicals found in water. 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.

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In this Proposed Interim Registration Review Decision, EPA is making no human health 

or environmental safety findings associated with the EDSP screening of 4-CP A. 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 EDSP component of the 4-CPA registration review case, the Agency 

has made the following proposed interim decisions: (1) no additional data are 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. Currently registered uses of 4-CP A 

are not expected to result in adverse effects to listed or non-listed species, or critical habitat. As 

such, EPA anticipates making a "no effect" determination under the ESA for all listed species 

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

chemicals. 2 http://www.epa.gov/endo/ 

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and no adverse modification of designated critical habitat for such species is expected for all 

currently registered uses of 4-CP A. 

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 4-CP A 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 decision, 

EPA may issue an Interim Registration Review Decision for 4-CP A (case 2115), in accordance 

with 40 CFR Sections 155.56 and 155.58. A final decision on the 4-CPA registration review case 

will also occur after an EDSP FFDCA section 408(p) determination has been made. 

EPA has created the following estimated timeline for the completion of 4-CP A . . registratiOn revtew: 

Registration Review for 4-CPA- Projected Registration Review Timeline 

Activities Estimated Date 

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

Review Decision 

Open Public Docket and Public Comment Period for Combined Work 2014- Sept 

Plan, Summary Document, and Proposed Interim Registration Review 

Decision 

Close Public Comment Period 2014- Nov 

Interim Registration Review Decision and Begin Post-Decision 

Follow-up3 

2015- January 

I Total (years) 0.5 

I 

3 A final decision on the 4-CPA registration review case, in accordance with 40 CFR Section155. 158, will occur 

after an EDSP FFDCA section 408(p) determination has been made. 

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Appendix- Additional Areas Considered in the 4-CP A 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. As described above, the U.S. and Canada have different 

tolerance/MRL levels for 4-CP A on mung bean sprouts based on residue data submitted to the 

respective pesticide regulatory agencies. EPA is interested to learn of any trade irritant issues 

arising from this disparity in levels. 

Water Quality: 

4-CP A is not identified as a cause of impairment for any water bodies listed as impaired under 

section 303(d) of the Clean Water Act.4 In addition, no Total Maximum Daily Loads (TMDL) 

have been developed for 4-CPA. 5 More information on impaired water bodies and TMDLs can 

be found at the Agency's website.6 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 OP P 's Registration Review Risk Assessment and Afanagement Process7 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 4-CPA 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. 

4 http://iaspub.epa.gov/tmdl waters 1 0/attains nation cy.cause detai l 303d?p cause group id=885 

5

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

group name=PESTICIDES 6 http://www .epa.gov/owow/tmdl/ 7 http://www.epa.gov/oppsrrd !/registration review/water quality sop.htm 

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