2

Rotenone Preliminary Work Plan – Table of Contents

Overview 3

Anticipated Data Needs 4

Statutory and Regulatory Authority 5

Chemical Facts 5

Use and Usage Information 5

Anticipated Risk Assessments for Registration Review 6

Timeline 9

Next Steps 9

Appendix – Additional Areas Considered in Rotenone’s

Registration Review 10

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 Ecological Risk and 

Environmental Fate, Endangered Species, and Drinking Water Assessments for Rotenone. 

Thomas Steeger, Cheryl Sutton. September 8, 2015.

2. Rotenone. Human Health Assessment Scoping Document in Support of Registration 

Review. Bridgett Bobowiec, Sumitra Bose Biswas, Nancy McCarroll. August 22, 2015.

3. BEAD Chemical Profile for Registration Review: Rotenone (071003). Colwell Cook, 

Cynthia Doucoure, Elizabeth Hill. March 11, 2015.

4. Rotenone: Tier I Review of Human Incidents. Elizabeth Evans, Shanna Recore. June 4, 

2015.

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

the docket EPA-HQ-OPP-2015-0572 at http://www.regulations.gov.
3

OVERVIEW

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

registration review (docket number EPA-HQ-OPP-2015-0572). Rotenone is a naturally 

occurring compound present in, and derived from the root of several plants. Rotenone is 

formulated as a restricted use piscicide used to manage fish populations in lakes, ponds, 

reservoirs, rivers, and streams. There are no agricultural or residential uses for rotenone. This 

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

knows about rotenone, identifies anticipated data and assessment needs, identifies the types of 

information that would be especially useful to the Agency in conducting the review, and

provides an anticipated timeline for completing the rotenone 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 rotenone and what types of new data or other 

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

rotenone. The Agency encourages all interested stakeholders to review the PWP, its Appendix, 

and support documents 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 PWP begins by listing the anticipated data needs for rotenone. Next, it discusses the 

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

rotenone’s chemical facts, use and usage information, recent actions, the anticipated risk 

assessments, and a projected registration review timeline. Finally, the Appendix to this 

document includes identification and discussion of some topics that are considered generally in 

Registration Review along with some additional chemical case-specific information.
4

ANTICIPATED DATA NEEDS

The table below summarizes anticipated data needs for rotenone. For additional discussion of 

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

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

for Rotenone (9/8/15) and Rotenone. Human Health Assessment Scoping Document in Support of 

Registration Review (8/22/15).

Anticipated Data Needs for Rotenone Registration Review

Guideline 

Number Study Title Test Material

Estimated 

Timeframe

(Months from 

receipt of DCI)

835.1230 Adsorption/Desorption TGAI 24

835.2120 Hydrolysis TGAI 24

835.2370 Aqueous Photolysis TGAI 24

835.4300 Aerobic Aquatic Metabolism TGAI 24

835.4400 Anaerobic Aquatic Metabolism TGAI 24

850.1010 Freshwater Invertebrate Acute Toxicity TEP 12

850.1025 Estuarine/Marine Mollusc Acute Toxicity TGAI 12

850.1075 Freshwater Fish Acute Toxicity – Rainbow trout TEP 12

850.2300 Avian Reproduction – waterfowl and upland 

game bird species TGAI 24

850.1735 Whole Sediment 10-Day Freshwater Invertebrate TGAI 12

NonGuidelineWhole Sediment Chronic Freshwater and/or 

Marine Invertebrate TGAI 24

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 the 

registration review program is provided on EPA’s website1

.

 1 http://www.epa.gov/oppsrrd1/registration_review/
5

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 opening 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 rotenone.

ROTENONE CHEMICAL FACTS

PC code 071003

Case Number 0255

CAS Number 83-79-4

Year first registered 1947

Pesticide Type Piscicide

Chemical class Isoflavone

Reregistration Eligibility 

Decision (RED)

Completed in 2007

Cumulative group NA

40 CFR Citation An exemption from tolerances was granted for rotenone, and the 

exemptions is currently listed under 40 CFR §180.905.

Non-pesticidal uses NA

Pesticide Re-evaluation 

Division, Chemical 

Review Manager

Kelly Ballard, ballard.kelly@epa.gov, (703) 305-8126

Registration Division, 

Product Manager

Mark Suarez, suarez.mark@epa.gov, (703) 306-0415

USE AND USAGE INFORMATION FOR ROTENONE

Please see the BEAD Chemical Profile for Registration Review: Rotenone (071003) in the 

registration review docket for more details.

Type of Pesticide Rotenone is a restricted use piscicide.

Use Sites There are no agricultural use sites for rotenone.

Non-agricultural use sites for rotenone are aquatic areas, 

including lakes, ponds, reservoirs, rivers, streams, and in 

aquaculture.

Summary of Usage EPA has limited data from other federal and state government 

agencies indicating small amounts of usage of rotenone.

Formulation Types Dust, liquid, emulsifiable concentrate, and wettable powder.
6

Application Methods Rotenone is applied with aircraft, backpack sprayer, drip can, or 

handheld or hand-directed nozzle to the water surface.

Technical Registrants There are no technical registrants*. However, there are three 

registrants with manufacturing formulation products: Central 

Garden & Pet Company, Foreign Domestic Chemical Corp, and 

TIFA International LLC.

Number of Registrations Twelve Section 3 products and two Section 24(c) products2. 

There is also an Experimental Use Permit.

Restricted Use Yes

*Please note: There are no technical registrants, only formulating registrants, due to the compound not being

synthesized but rather extracted and then formulated into the product.

ANTICIPATED RISK ASSESSMENTS FOR REGISTRATION REVIEW

The most recent comprehensive ecological risk assessment for rotenone was completed in 2006 

in support of the RED. The most recent comprehensive human health risk assessment was also 

completed in 2006 in support of the RED. Findings and conclusions from these risk assessments 

are summarized in the Registration Review: Preliminary Problem Formulation for Ecological 

Risk and Environmental Fate, Endangered Species, and Drinking Water Assessments for 

Rotenone (9/8/15) and Rotenone. Human Health Assessment Scoping Document in Support of 

Registration Review (8/22/15).

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

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

For human health, EPA anticipates the need to conduct revised dietary (drinking water only), 

residential post-application, and occupational risk assessments during registration review.

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

Problem Formulation and Scoping Document.

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

(http://oaspub.epa.gov/pestlabl/ppls.home).
7

Anticipated Risk Assessments for Rotenone Registration Review

Type of Risk Assessment Conduct? Notes

Ecological and Environmental Fate

Comprehensive ecological 

risk assessment, including 

endangered species 

Y 

Ecological Incidents Will check 

for updates

For a discussion of reported ecological incidents for 

rotenone, see page 12 of the Problem Formulation.

Human Health

Dietary

Food N There are no food uses registered for rotenone; 

therefore a dietary exposure assessment for food in not 

required.

Drinking water Y The Agency anticipates updating the drinking water 

analysis for rotenone, and so an updated dietary 

assessment for water only is anticipated for registration 

review.

Occupational

Handlers (mixers, loaders, 

applicators)

Y An updated quantitative occupational handler exposure 

assessment for all formulations and application 

scenarios is needed for registration review.

Post-application N It is unlikely that workers will come in contact with 

previously rotenone-treated water and any postapplication exposure is likely less than exposure to 

handlers and applicators. Therefore a quantitative 

occupational post-application exposure assessment is 

not anticipated for registration review.

Residential

Handlers N There are no proposed or current residential uses for 

rotenone; therefore a quantitative residential handler 

exposure assessment is not anticipated for registration 

review.

Post-application Y The Agency anticipates updating its residential postapplication swimming analysis (for possible exposure 

to those who may swim in rotenone-treated waters).

The need for a spray drift and volatilization assessment 

may be considered for registration review.

Other

Aggregate Y An updated aggregate assessment may incorporate 

updated dietary (drinking water only) and updated 

residential post-application exposures.

Cumulative N The Agency has not determined whether rotenone

shares a common mechanism of toxicity with other 

chemical substances.
8

Tolerances N As per 40 CFR §180.905, rotenone is exempt from the 

requirement of a tolerance on all food commodities.

Human Health Incidents Will check 

for updates

For a discussion of reported human health incidents for 

rotenone, see pages 8-9 of the Scoping Document and 

the Rotenone: Tier I Review of Human Incidents

document.

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

ecological information requested for this registration review, and of particular interest to 

EPA, is described below.

• 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 geographic limitations on use.

• Use distribution (e.g., 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 information – national, state, and county.

• Usage/use information.

• Typical application interval (days).

• State or local use restrictions.

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

US market (if applicable).

• 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).

TIMELINE

EPA has created the following estimated timeline for the completion of rotenone’s registration

review.

Registration Review for Rotenone – Projected Registration Review Timeline

Activities Estimated Date

Opening the Docket

Open Docket and Public Comment Period 2015 – September

Close Public Comment 2015 – November

Case Development

Final Work Plan 2016 – February

Issue DCI 2016 – April – June

Data Submission 2018 – April – June
9

Registration Review for Rotenone – Projected Registration Review Timeline

Activities Estimated Date

60-Day Public Comment Period for Draft Risk Assessments3 2019 – October –

December

Registration Review Decision

60-Day Public Comment Period for Proposed Registration Review 

Decision 

2020 – July –

August

Registration Review Decision and Begin Post-Decision Follow-up 2021

Total (years) 6

NEXT STEPS

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

comments received in a timely manner and then issue a Final Work Plan for the registration 

review of rotenone.

 3 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.
10

Appendix – Additional Topics Considered in the Rotenone 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.

Water Quality:

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

section 303(d) of the Clean Water Act4

. In addition, no Total Maximum Daily Loads (TMDL) 

has been developed for rotenone5. More information on impaired water bodies and TMDLs can 

be found at the Agency’s website6. The Agency invites submission of water quality data for 

this pesticide. To the extent possible, submissions should include the key data elements noted in 

the OPP Guidance for Submission of State and Tribal Water Quality Monitoring Data7 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 rotenone 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:

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

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

allow the Agency to determine whether rotenone’s use 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.

 4 http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_cause_group_id=885 5

http://iaspub.epa.gov/tmdl_waters10/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/oppsrrd1/registration_review/water_quality_sop.htm
11

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 re-registration decision for rotenone, 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), rotenone 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, 20138 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.9

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

chemicals. 9 http://www.epa.gov/endo/
12

HUMAN STUDIES:

Occupational and Residential

Past rotenone 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), the Agricultural 

Reentry Task Force (ARTF) Database, and the Outdoor Residential Exposure Task Force 

(ORETF) Database. EPA has reviewed all the studies supporting these multi-pesticide generic 

exposure databases, and has found no clear and convincing evidence that the conduct of any of 

them was either fundamentally unethical or significantly deficient relative to the ethical 

standards prevailing at the time the research was conducted. All applicable requirements of 

EPA’s Rule for the Protection of Human Subjects of Research (40 CFR Part 26) have been 

satisfied, and there is no regulatory barrier to continued reliance on these studies.