2

Propanil Preliminary Work Plan – Table of Contents

OVERVIEW ................................................................................................................................... 3

ANTICIPATED DATA NEEDS .................................................................................................... 4

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

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

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

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

ANTICIPATED RISK ASSESSMENTS FOR REGISTRATION REVIEW................................ 7

TIMELINE.................................................................................................................................... 10

NEXT STEPS ............................................................................................................................... 11

Appendix – Additional Areas Considered in the Propanil Registration Review...................... 12

References:

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

based on the following documents:

1. Registration Review: Preliminary Problem Formulation for Environmental Fate, 

Ecological Risk, Endangered Species, and Drinking Water Exposure Assessments for 

Propanil. Ryan Mroz, He Zhong, and Edom Seifu. April 28, 2015.

2. Propanil: Registration Review Human Health Scoping Document. Mohsen Sahafeyan, 

Evisabel Craig, and Shalu Shelat. April 23, 2015.

3. Propanil: Tier I Review of Human Incidents. Shanna Recore and Elizabeth Evans. January 

8, 2015.

4. BEAD Chemical Profile (BCP) for Registration Review: Propanil (028201). Sunil 

Ratnayake, Sepehr Haddad, and Stephen Smearman. December 2, 2014.

5. Propanil (028201) Screening Level Usage Analysis (SLUA). July 18, 2014.

6. EFED Table 1 Report, Propanil (028201). November 24, 2014.

7. HED Master Label Report, Propanil (028201). November 24, 2014.

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

the docket EPA-HQ-OPP-2015-0052 at http://www.regulations.gov.
3

OVERVIEW

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

registration review (docket number EPA-HQ-OPP-2015-0052). This Preliminary Work Plan 

(PWP) document explains what EPA's Office of Pesticide Programs knows about propanil, 

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 propanil.

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 propanil and what types of new data or other 

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

propanil. 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 decisionmaking 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: 

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 Preliminary Work Plan begins by listing the anticipated data needs for propanil. 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 propanil. 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 propanil. For additional discussion of the 

anticipated data needs, see the Registration Review: Preliminary Problem Formulation for 

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

Assessments for Propanil and Propanil: Registration Review Human Health Scoping Document.

Table 1: Anticipated Data Needs for the Propanil Registration Review

Guideline 

Number1 Study Title1

Test Material

Estimated 

Timeframe

(Months from 

receipt of DCI)

Anticipated Data Needs for the Parent Propanil

835.4100 Aerobic soil metabolism TGAI 24

850.6100

Environmental chemistry methods and 

associated independent laboratory validation for 

water

TGAI 24

850.2100 Avian acute oral toxicity with a passerine species TGAI 12

850.3040 Full-Field testing for pollinators TEP 24

870.6200 Acute neurotoxicity TGAI 12

875.2100 Dislodgeable foliar residue in rice TGAI 12

875.1100 Dermal exposure-outdoor2 TEP 8

NonGuideline

(OECD 213)

Acute oral toxicity to adult honey bees

TGAI 12

NonGuidelineChronic oral toxicity to adult honey bees TGAI 12

NonGuidelineChronic oral toxicity to larval honey bees 

including acute endpoints TGAI 12

NonGuideline Residues in pollen and nectar TEP 24

NonGuideline 

(OECD 75)

Semi-Field Testing for Honeybees TEP 24

Anticipated Data Needs for the 3,4-DCA Degradate

835.4100 Aerobic soil metabolism DEGR 24

835.4300 Aerobic aquatic metabolism DEGR 24

 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, 2012. 

http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPPT-2009-0154-0028 2 This study was requested as part of the RED DCI and while information was submitted, there are still uncertainties 

associated with dermal exposure, so additional study data is still being requested. For those systems determined to 

be closed systems or closed system equivalent, the registrant should submit a waiver request to EPA at the time of 

the DCI.
5

Table 1: Anticipated Data Needs for the Propanil Registration Review

Guideline 

Number1 Study Title1

Test Material

Estimated 

Timeframe

(Months from 

receipt of DCI)

835.4400 Anaerobic aquatic metabolism DEGR 24

850.6100

Environmental chemistry methods and 

associated independent laboratory validation for 

water

DEGR 24

Outstanding Data Requirements from GDCI-028201-178933

850.2200 Avian subacute dietary toxicity - bobwhite 

quail DEGR Overdue

850.4100 Terrestrial plant toxicity, seedling emergence

(Tier 1) DEGR Overdue

850.4150 Terrestrial plant toxicity, vegetative vigor (Tier 

1) DEGR Overdue

870.3465 90-day inhalation toxicity TGAI Overdue

TGAI = technical grade active ingredient; TEP = typical end-use product; DEGR = degradate

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 

 3 The studies listed in this section were previously required through a generic data call-in issued in April 2006 and 

are still outstanding. These studies will not be included in the anticipated Registration Review DCI because they 

are already required through the earlier DCI. 4 http://www.epa.gov/oppsrrd1/registration_review/
6

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 propanil.

CHEMICAL FACTS

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

Table 2: Chemical Facts for Propanil

PC code 028201

Case Number 0226

CAS Number 709-98-8

Year first registered 1973

Pesticide Type Herbicide

Chemical class Amide

Reregistration Eligibility 

Decision (RED)

2003, amended in 2006

Tolerance Reassessment 

Eligibility Decision 

(TRED)

Not applicable, tolerance reassessment was included in the RED

Cumulative group Not applicable

40 CFR Citation Tolerances for propanil and its degradate are established in 40 

CFR §180.274.

Dual-use Propanil 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 propanil

Pesticide Re-evaluation 

Division, Chemical 

Review Manager

Joel Wolf, wolf.joel@epa.gov, 703-347-0228

Registration Division, 

Product Manager

Reuben Baris, baris.reuben@epa.gov, 703-305-7356

USE AND USAGE INFORMATION

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

Profile (BCP) for Registration Review: Propanil (028201) in the registration review docket for 

more details.

Table 3: Propanil Use and Usage Information

Summary of Use Post-emergence herbicide to control certain grasses and broadleaf 

weeds in rice production. This herbicide has no residual activity.

Use Sites Agricultural Use Sites

Rice is the only registered agricultural use site for propanil.

Non-Agricultural Use Sites
7

Table 3: Propanil Use and Usage Information

There are no registered non-agricultural use sites for propanil.

Summary of Usage Based on private market usage data from 1998-2012, usage 

averaged approximately 6 million pounds active ingredient (a.i.) 

applied annually on 1.8 million acres treated. The average a.i. rate

over this time period was 3.34 lbs a.i./acre. From 2004-2012 on 

average 45 percent of the rice crop was treated with propanil.

Formulation Type(s) Emulsifiable concentrate liquid, water dispersible granule (dry

flowable), soluble concentrate liquid, and flowable concentrate 

liquid

Application Method(s) Typically applied as a broadcast treatment with ground boom 

sprayers and aerial equipment.

Technical Registrant(s) RiceCo, LLC; Willowood Propanil, LLC; ProNil, LLC

No. of Registrations 41 Section 3 products5

Restricted Use 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.

• Certain propanil labels are unclear with respect to application parameters such as 

retreatment intervals. Without further information, EPA expects to use conservative 

assumptions to approximate this parameter in order to conduct a quantitative risk 

assessment. However, the Agency will work with registrants to clarify information on

propanil product labels.

• Confirmation of the following label information: frequency of application, application 

intervals, and maximum number of applications per season.

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

state, and county.

• Foreign technical registrants not listed above who supply technical propanil to the US 

market.

RECENT ACTIONS

Recently, EPA has required registrants to utilize a closed-system for their dry flowable 

formulations.

ANTICIPATED RISK ASSESSMENTS FOR REGISTRATION REVIEW

The most recent comprehensive human health risk assessment for propanil was completed in 

March 2003 in preparation for the Reregistration Eligibility Decision. An addendum to the risk 

assessment was completed in June 2011. The most recent ecological and environmental fate risk 

assessment was completed in March 2003 in preparation for the Reregistration Eligibility 

Decision. Additionally, a California red-legged frog endangered species assessment was 

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

(http://oaspub.epa.gov/pestlabl/ppls.home).
8

completed in 2009. Findings and conclusions from these risk assessments are summarized in the 

Registration Review: Preliminary Problem Formulation for Environmental Fate, Ecological 

Risk, Endangered Species, and Drinking Water Exposure Assessments for Propanil and 

Propanil: Registration Review Human Health Scoping Document.

During registration review, the Agency anticipates the need to conduct a comprehensive

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

For human health, EPA anticipates the need to conduct revised dietary and occupational risk 

assessments 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 below summarizes the anticipated registration review risk assessments based on the 

EFED Problem Formulation and HED Scoping Document.
9

Table 4: Anticipated Risk Assessments for the Propanil Registration Review

Type of Risk Assessment Conduct? Notes

Ecological and Environmental Fate

Comprehensive ecological 

(species to be assessed 

include terrestrial and aquatic 

organisms), including 

endangered species 

Y EPA anticipates conducting an updated 

comprehensive ecological risk assessment during 

registration review. The new assessment will 

incorporate the most up-to-date modeling 

methodologies, updated toxicological endpoints, and 

data submitted under the anticipated registration 

review Data Call-In Notice. 

Incidents Will check for 

updates

For a discussion of reported ecological incidents for 

propanil, see page 17 of the Problem Formulation. A 

formal review is not planned, but the agency will 

continue to monitor incident data throughout 

registration review.

Human Health

Dietary

Food Y An updated dietary exposure and risk assessment, 

which incorporates changes to points of departures 

and uncertainty factors, includes updated drinking 

water estimates, as well as updated percent crop 

treated information may need to be completed to 

support registration review.

Drinking water Y

Occupational

Handlers (mixers, loaders, 

applicators)

Y The occupational exposure/risk assessments for 

propanil may need to be reassessed to address 

updates to exposure policies, including updates to 

exposure data used for handler scenarios, postapplication transfer coefficients, transferable residue 

assumptions, and assumptions for body weights. A 

reassessment may also need to be done if changes to 

the toxicity endpoints or uncertainty factors are made 

during registration review.

Post-application Y

Residential

Handlers N There are no residential uses for propanil; therefore, 

a residential exposure assessment will not be 

required. However, residential bystander exposures 

resulting from off-site transport (e.g., spray drift or 

volatilization) may occur as a result of applications 

of propanil. EPA is currently evaluating these types 

of exposures and will examine the need for spray 

drift and volatilization assessments for propanil

during registration review.

Post-application N

Other
10

Aggregate N There are currently no residential uses for propanil; 

therefore the propanil aggregate risk assessment 

includes only dietary exposure (food and water) 

which may need to be updated.

Cumulative N Propanil has not been identified as a member of a 

cumulative group that shares a common mechanism 

of toxicity. 

Tolerances N Tolerances are established under 40 CFR §180.274 

for the combined residues of the herbicide propanil 

(3′, 4′-dichloropropionanilide) and its metabolites 

convertible to 3, 4-dichloroaniline (3, 4-DCA). At 

this time, there are no pending requests to establish a 

new propanil tolerance.

Incidents Will check for 

updates

For a discussion of reported human incidents for 

propanil, see page 8 of the Scoping Document and 

the Propanil: Tier I Review of Human Incidents. A 

formal review is not planned, but the agency will 

continue to monitor incident data throughout 

registration review.

TIMELINE

EPA has created the following estimated timeline for the completion of the propanil registration

review in Table 5 below.

Table 5: Projected Propanil Registration Review Timeline

Activities Estimated Date

Opening the Docket

Open Docket and 60-day Public Comment Period 2015 - June

Close Public Comment 2015 - August

Case Development

Final Work Plan 2015 – November

Issue DCI 2016 Jan. - March

Data Submission 2018 Jan. - March

60-day Public Comment Period for Draft Risk 

Assessments6

2019 July – Sept.

Registration Review Decision

60-day Public Comment Period for Proposed 

Registration Review Decision

2020 Oct. – Dec.

Registration Review Decision and Begin Post-Decision 

Follow-up

2021

Total (years) 6

 6 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 155.53(c). For conventional pesticides, the 

Agency plans to provide a 60 calendar day public comment period generally for draft risk assessments.
11

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 Final Work Plan for the registration 

review of propanil.
12

Appendix – Additional Areas Considered in the Propanil 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 of MRLs 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:

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

section 303(d) of the Clean Water Act.

7

 In addition, no Total Maximum Daily Loads (TMDL) 

have been developed for propanil.

8

 More information on impaired water bodies and TMDLs can 

be found at the Agency’s website.

9 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 Process10

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 propanil 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.

ENDANGERED SPECIES:

 7 http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=885 8

http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_group_id=885&p_pollutant_

group_name=PESTICIDES 9 http://www.epa.gov/owow/tmdl/

10 http://www.epa.gov/oppsrrd1/registration_review/water_quality_sop.htm
13

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

conducted for propanil. The ecological risk assessment planned during registration review will 

allow the Agency to determine whether use of propanil 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 

and/or National Marine Fisheries Service (the Services), as appropriate.

On June 5, 2013, the Center for Biological Diversity and the Pesticide Action Network North 

America filed an amended complaint in its lawsuit in the United States District Court for the 

Northern District of California, against the EPA for allegedly failing to undergo consultation 

with the United States Fish and Wildlife Service and the National Marine Fisheries Service 

regarding the effects of over 50 pesticides, including propanil, on over 100 endangered and 

threatened species throughout the United States (Center for Biological Diversity, et al. v. EPA, et 

al., No. C 11-00293 (N.D.Cal.).

A previous endangered species assessment was conducted for propanil in October 2009. The 

assessment was conducted for California red-legged frog.

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 propanil, 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), propanil 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 
14

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, 201311 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 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.12

HUMAN STUDIES:

Occupational

Past propanil 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 of Human Subjects of Research (40 

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

these studies.

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

chemicals. 12 http://www.epa.gov/endo/