2

Fenamidone Preliminary Work Plan – Table of Contents

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

ANTICIPATED DATA NEEDS .................................................................................................... 3

STATUTORY AND REGULATORY AUTHORITY................................................................... 4

CHEMICAL FACTS ...................................................................................................................... 4

USE AND USAGE INFORMATION............................................................................................ 5

RECENT ACTIONS....................................................................................................................... 6

ANTICIPATED RISK ASSESSMENTS FOR REGISTRATION REVIEW................................ 6

TIMELINE...................................................................................................................................... 8

NEXT STEPS ................................................................................................................................. 8

Appendix – Additional Areas Considered in the Fenamidone Registration Review.................. 9

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 the Ecological Risk 

Assessment and Drinking Water Exposure Assessment to be Conducted for Fenamidone. 

Wolf and Stebbins. February 6, 2014.

2. Fenamidone: Human Health Risk Assessment Scoping Document in Support of 

Registration Review. Britton et al. February 28, 2014.

3. Fenamidone: Tier I Review of Human Incidents. E. Evans and S. Recore. November 20, 

2013. 

4. BEAD Chemical Profile (BCP) for Registration Review: Fenamidone. Yourman et al. 

September 18, 2013. 

5. Fenamidone Screening Level Use Analysis (SLUA). March 23, 2013.

6. EFED Table 1 Report. September 6, 2013.

7. HED Master Label Report. September 6, 2013.

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

in the docket EPA-HQ-OPP-2014-0048 at http://www.regulations.gov.
3

OVERVIEW

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

registration review (docket number EPA-HQ-OPP-2014-0048). Fenamidone is an imidazoline 

fungicide registered for use to control downy mildew and Pythium species and to manage 

Alternaria species, rust, early and late blight, and several other pathogens. It is currently

registered for use on leafy vegetables (both Brassica and non Brassica); turnip greens; carrots; 

cotton; cucurbits; grapes; potatoes, various bulb/root/tuberous/corm vegetables; tomatoes, 

peppers and other fruiting vegetables; sunflower; tobacco; and commercial greenhouse 

ornamentals. Fenamidone is also registered for use as a seed treatment of sunflower and cotton. 

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

knows about fenamidone, 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 fenamidone.

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 fenamidone and what types of new data or 

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

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

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

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

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

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

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 fenamidone. 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 fenamidone. 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.

ANTICIPATED DATA NEEDS

Table 1 summarizes anticipated data needs for fenamidone. For additional discussion of the 

anticipated data needs, see the documents, Registration Review – Preliminary Problem 

Formulation for the Ecological Risk Assessment & Drinking Water Exposure Assessment to be 

Conducted for Fenamidone and Fenamidone: Human Health Risk Assessment Scoping 

Document in Support of Registration Review. 
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Table 1: Anticipated Data Needs for the Fenamidone Registration Review

Guideline 

Number Study Title

Test Material

Estimated 

Timeframe

(Months from 

receipt of DCI)

850.6100 Environmental chemistry methods & associated 

independent laboratory validations for water TGAI 12

850.1075 Freshwater fish toxicity (fathead minnow) TGAI 12

850.4150 Vegetative vigor TEP 12

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

STATUTORY AND REGULATORY AUTHORITY

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

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

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

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

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

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

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

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

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

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

program is provided on EPA’s website.

1

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 fenamidone.

CHEMICAL FACTS

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

Table 2: Chemical Facts for Fenamidone

PC code 046679

Case Number 7033

 

1

http://www.epa.gov/oppsrrd1/registration_review/
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Table 2: Chemical Facts for Fenamidone

CAS Number 161326-34-7

Year first registered 2002

Pesticide Type Fungicide 

Chemical class Imidazolinone (quinone outside inhibitors)

Reregistration Eligibility 

Decision (RED)

Not applicable. Because fenamidone was first registered in 2002, it was 

not subject to reregistration. 

Tolerance Reassessment 

Eligibility Decision (TRED)

Not applicable. Because fenamidone was first registered in 2002, it was 

not subject to tolerance reassessment. 

Cumulative group Fenamidone has not been identified as a member of a cumulative group 

that shares a common mechanism of toxicity. 

40 CFR Citation Tolerances for fenamidone are established in 40 CFR § 180.579.

Dual-use Fenamidone is registered for conventional pesticidal uses only.

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

Pesticide Re-evaluation 

Division, Chemical Review 

Manager

Christina Scheltema, Scheltema.christina@epa.gov, (703)308-2201

Registration Division, Product 

Manager

Tony Kish, kish.tony@epa.gov, (703)308-9443

USE AND USAGE INFORMATION

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

Chemical Profile (BCP) for Registration Review: Fenamidone in the registration review docket 

for more details.

Table 3: Fenamidone Use and Usage Information

Summary of Use Fungicide registered for use to control and manage a variety of pathogens, 

including mildew, Pythium, Alternaria, rust, and early and late blight.

Use Sites Leafy vegetables; turnip greens; carrots; cotton; cucurbits; grapes; 

potatoes; various bulb, root, and tuberous vegetables; tomatoes; peppers; 

sunflower; tobacco; and commercial greenhouse ornamentals. Also

registered for use as seed treatment for sunflower and cotton. 

Summary of Usage Between 2005 and 2011, approximately 23,000 lbs of fenamidone were 

applied annually to 106,000 acres, at an average application rate of 0.2 lbs 

ai/A.

Formulation Type(s) Emulsifiable concentrate.

Application Method(s) Foliar spray, in-furrow treatment, chemigation, and aerial application. 

Technical Registrant(s) Bayer CropScience

No. of Registrations One technical and two end-use products.

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 fenamidone labels are unclear with respect to application parameters such as 

minimum retreatment intervals and maximum seasonal or annual application rates (e.g., 

the number of applications of fenamidone that can be applied per calendar year on a 
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given field is not explicitly stated on current labels). Without further information, EPA 

expects to use conservative assumptions to approximate these parameters in order to 

conduct a quantitative risk assessment. However, the Agency will work with registrants 

to clarify information on fenamidone product labels. 

 Confirmation of the following label information: sites of application; formulations;

application methods and equipment; maximum application rates; frequency of 

application, application intervals, and maximum number of applications per season and 

per year; and geographic limitations on use.

 Use distribution (e.g., acreage and geographical distribution of relevant use sites).

 Median and 90th percentile reported use rates (lbs ai/A) from usage data – national, state, 

and county.

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

state, and county.

 Efficacy data for crops where fenamidone may be particularly effective and used 

preferentially rather than other registered fungicides. 

 Usage/use information seed treatment and any use on non-agricultural uses.

 Typical application interval (days).

 State or local use restrictions.

 Foreign technical registrants not listed above who supply technical fenamidone to the US 

market.

RECENT ACTIONS

EPA established new tolerances for residues of fenamidone in/on ginseng, onions, and other 

crops in March 2014. The Agency anticipates amending fenamidone registrations to allow these 

uses in the near future. The Agency has recently completed risk assessments as part of its review 

of the tolerance petition and application to amend the fenamidone registration; these assessments 

may be found in the regulatory docket (EPA-HQ-OPP-2013-0161). 

ANTICIPATED RISK ASSESSMENTS FOR REGISTRATION REVIEW

Other than the assessments mentioned above, the most recent comprehensive human health risk 

assessment for fenamidone was completed in July 2011 and the most recent ecological and 

environmental fate risk assessment was completed in 2009. Findings and conclusions from these 

risk assessments are summarized in the Registration Review – Preliminary Problem Formulation 

for the Ecological Risk Assessment and Drinking Water Exposure Assessment to be Conducted 

for Fenamidone and Fenamidone: Human Health Risk Assessment Scoping Document in 

Support of Registration Review.

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

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

fenamidone. For human health, EPA does not anticipate the need to conduct revised dietary, 

residential, and occupational risk assessments during registration review with the possible 

exception of a residential bystander assessment. However, if toxicological endpoints or points of 

departure are revised, or if there are changes to the standard operating procedures or default
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exposure assumptions, then EPA anticipates evaluating the need to conduct revised human health 

risk assessments.

Table 4 summarizes the anticipated registration review risk assessments based on the EFED 

Problem Formulation and HED Scoping Document.

Table 4: Anticipated Risk Assessments for the Fenamidone Registration Review

Type of Risk Assessment Conduct? Notes

Ecological and Environmental Fate

Comprehensive ecological 

assessment (species to be assessed 

include terrestrial and aquatic 

organisms), including endangered 

species 

Yes The anticipated ecological risk assessment will support a 

complete endangered species determination for fenamidone. 

The anticipated risk assessment will be conducted on the 

parent compound. 

Incidents Will check for 

updates

For a discussion of reported ecological incidents for 

fenamidone, see pages 19 and 20 of the Problem 

Formulation.

Human Health

Dietary

Food No EPA does not anticipate conducting a dietary risk assessment 

unless the toxicology points of departure, uncertainty factors, 

or estimated drinking water concentrations change. 

Drinking water No

Occupational

Handlers (mixers, loaders, 

applicators)

No EPA does not anticipate conducting an occupational risk 

assessment unless the toxicology points of departure or 

uncertainty factors for dermal and/or inhalation exposure 

change. 

Post-application No

Residential

Handlers No Fenamidone is not registered for residential use. However, 

Post-application Yes EPA may need to conduct a residential bystander assessment.

Other

Aggregate No Evaluates the combined risk from dietary and residential 

exposures. 

Cumulative No Fenamidone is not a member of a cumulative group. 

Tolerances Yes EPA anticipates updating fenamidone tolerances, established 

in 40 CFR §180.579, to align with new crop groups and, 

where possible, to harmonize with international MRLs. 

Incidents Will check for 

updates

At present, EPA is aware of only one reported human 

incident for fenamidone. For details, see Fenamidone: Tier I 

Review of Human Incidents.

Guidance for Commenters: Additional ecological information requested for this 

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

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

mammalian mortalities) not already reported to the Agency.

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

 Number of crop cycles per year for crops that may have multiple growing seasons. 
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TIMELINE

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

registration review in Table 5.

Table 5: Projected Fenamidone Registration Review Timeline

Activities Estimated Date

Opening the Docket

Open Docket and 60-day Public Comment Period 2014 – March

Close Public Comment 2014 – May

Case Development

Final Work Plan 2014 – August

Issue DCI 2014 Oct. – Dec.

Data Submission 2015 Oct. – Dec.

60-day Public Comment Period for Draft Risk Assessments22017 April – June

Registration Review Decision

60-day Public Comment Period for Proposed Registration 

Review Decision

2018 Jan. – March

Registration Review Decision and Begin Post-Decision 

Follow-up

2019

Total (years) 5

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 fenamidone.

 

2 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.
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Appendix – Additional Areas Considered in the Fenamidone 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:

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

under section 303(d) of the Clean Water Act.

3

 In addition, no Total Maximum Daily Loads 

(TMDL) have been developed for fenamidone.

4

 More information on impaired water bodies and 

TMDLs can be found at the Agency’s website.

5 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 Process6in 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 fenamidone 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.

 

3

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

4

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

group_name=PESTICIDES

5

http://www.epa.gov/owow/tmdl/

6

http://www.epa.gov/oppsrrd1/registration_review/water_quality_sop.htm
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ENDANGERED SPECIES:

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

conducted for fenamidone. The ecological risk assessment planned during registration review 

will allow the Agency to determine whether use of fenamidone 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.

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 fenamidone, 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), 

fenamidone 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, 20137and includes some 

 

7

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

chemicals.
11

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.8

HUMAN STUDIES:

Occupational

Past fenamidone 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.

 

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