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Metofluthrin Final Work Plan

Registration Review

Case Number 7445

December,2013

Approved by: S1?& p

Richard P. Keigwin, Jr.

Director

Pesticide Re-evaluation Division

Date:
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INTRODUCTION

This is the Environmental Protection Agency's (EPA or the Agency) Final Work Plan (FWP) for 

the registration review of metofluthrin. This work plan addresses public comments received 

concerning the Preliminary Work Plan (PWP), which was posted in the metofluthrin registration 

review docket (EPA-HQ-OPP-2012-0105). Metofluthrin is a Type 1 synthetic pyrethroid insect 

repellent and insecticide with products registered for use in residential and commercial areas, 

including barns. stables. and kennels. There are a number of products containing metofluthrin 

as the sole active ingredient that are registered for use as repellents for adult mosquitoes. These 

products are an impregnated paper repellent strip. a battery-operated personal outdoor insect 

repellent fan, an impregnated fiberglass ring heated by a candle, and a recently registered

battery-operated automated mister. Metotluthrin also is co-formulated with piperonyl butoxide

and clothianidin, and registered for use to kill.bed bugs. There are no registered food/feed uses.

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. Changes in

science, public policy, and pesticide use practices occur over time. 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. The public phase

of registration review begins when the initial docket is opened for each case. Information on this 

program is provided on the Agency's website. 1

The FWP begins with any updates since the PWP was issued. Next is a summary of substantive 

comments received during the public comment period for the PWP concerning anticipated data 

needs, expected risk assessments, or the estimated timeline identified in the PWP, and a summary 

of the Agency's responses to those comments. This section is followed by registration review 

planned data needs, risk assessments expected to be conducted, and the projected registration 

review timeline for metofluthrin. Lastly, there is a discussion of next steps.

UPDATES SINCE THE PWP WAS ISSUED

There are no additional updates on metofluthrin since the PWP.

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http://www.epa.gov/opp.srrd 1/registration_review/
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SUMMARY OF COMMENTS AND AGENCY RESPONSES

During the 60-day public comment period on the Metofluthrin Preliminary Work Plan, this opened 

on June 6, 2013 and closed on August 26, 2013, the Agency received 4 public comments. 

Comments were submitted by the San Francisco Bay Regional Water Quality Control Board, the 

Central Valley Regional Water Quality Control Board, and the California Stormwater Quality 

Association.

The comments do not address the timeline described in the PWP, but they do address the planned 

ecological and human health risk assessments and data requirements. In the PWP, EPA also solicited

comments on the specific topics of environmental justice, water quality concerns, and trade irritants,

but no comments or information were received on those issues.

This section does not capture every comment made on the PWP nor all the Agency's responses. A 

full listing of all public comments and EPA responses in their entirety are located in the docket, 

EPA-HQ-OPP-2012-0105. Those public comments and Agency responses related to the 

anticipated ecological risk assessment or data needs can be found in the Summary of Public 

Comments Received on the Preliminary Ecological Risk Assessment and Endangered Species 

Effects Determination Conducted for the Registration Review of Metojluthrin.

Comments submitted by all three organizations; the San Francisco Bay Regional Water 

Quality Control Board, the Central Valley Regional Water Quality Control Board, and the 

California Stormwater Quality Association in EPA-HQ-OPP-2012-0105.

1 . Comment: The data and modeling required of other pyrethroids undergoing registration review 

should also be required for metofluthrin; metofluthrin's environmental risk assessment should 

include a quantitative assessment of the same level of rigor as the risk assessments for all other 

pyrethroids; and that all pyrethroids should be reviewed together as a group.

Response: The Environmental Fate and Effects Division plans to review and respond to these 

comments at the same time that the Health Effects Division responds to comments received on 

the human health risk assessment during the next phase of registration review, currently 

scheduled for June 2014

PLANNED DATA NEEDS

The Agency does not anticipate requiring any additional data at this time, although the Agency 

intends to revisit the human incident data base for incidents associated with the use of metofluthrin 

prior to releasing its preliminary human health risk assessment.
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DE MINIMIS DETERMINATION

The Science Policy C<mncil/Risk Management Forum De Minimis Subgroup determined which 

metofluthrin met the criteria for the EPA's de minimis policy for registration review. As part of the 

registration review process, the Agency selected metofluthrin as a de minimis candidate due to its 

low potential for ecological risk and exposure and effects to non-target organisms. The most recent 

ecological and environmental fate risk assessment was completed April 16, 2013. These risk 

assessments are contained in Registration Review: Preliminary Ecological Risk Assessment and 

Endangered Species Effects Determinationfor Metofluthrin. Also see De Minimis Subgroup 

Opinion on Meto.fluthrin located in the metofluthrin docket. The Agency has not made a 

determination that the human health risks associated with the use of metofluthrin meet appropriate 

de minimis criteria.

RISK ASSESSMENTS FOR REGISTRATION REVIEW

Table 1 below summarizes the planned registration review risk assessments based on the EFED 

Problem Formulation and HED Scoping Document and the planned assessments have not changed 

from what was included in the PWP.

Table 2: Planned Risk Assessments for the MetofluthrinRegistration Review

Type of Risk Assessment Conduct? Notes

Ecolosrlcal and Environmental Fate

Comprehensive ecological

(species to be assessed

include terrestrial and aquatic 

organisms), including 

endangered species

N The Agency has concluded that there are no risks

of concern to listed and non-listed species assoc iated 

with the current uses of metofluthrin, so a new 

assessment will not be needed for registration review.

Incidents Will check for

updates

There are no ecological incidents reported for 

metotluthrin. Any new incident information becoming 

available during registration review wi II be

considered.

Human Health

Dietary

Food N There are no proposed or currently registered food

uses for metofluthrin. so a food-only dietary

assessment is not needed.

Drinking water N Drinking water exposure is not expected based on

the indoor and limited outdoor uses of metotluthrin, so 

a revised drinking water assessment is not expected to

be needed.

Occupational

Handlers (mixers, loaders,

applicators)

N Based on the findings from the current assessment,

an updated assessment is not expected to be needed.

Post-application N A quanti tative occupational post-application

expos ure assess ment has not been conducted and is

not expected to be needed for registration review.

Residential
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Handlers N Based on the fi ndings from the current assessment, 

new residential handler assessments are not expected 

to be needed.

Post-application N Based on the findings from the cunent assessment, 

the Agency does not expect that new residential po:-.tapplication risk assessments wil l be needed.

Other

Aggregate N Because there are no dietary risk concern t<.H

rnerofl uthri n. an aggregate assessment is not expected

to be needed.

Cumulative N A·new cumulative risk assessment that includes 

metofluthrin is not eXQected to be needed.

Tolerances N There are no food uses for metotluthrin, so tolerances 

are not needed.

Incidents Will check for A limited number of human health incidents have 

updates been reported for metotluthrin. Because metotluthrin

is a relatively new pesticide, the incident data will be 

re-assessed as the Agency approaches its registration

review decision.

TIMELINE

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

metofluthrin registration review in Table 2 below.

Table 2: Registration Review for Metofluthrin Registration Review Timeline

Activities Estimated Date

Opening the Docket

Open Docket and 60-day Public Comment Period 2013-June-Completed

Close Public Comment 2013-August- Completed

Case Development

Final Work Plan 2013-December-Completed

60-day Public Comment Period for Draft Risk Assessments

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2014-April-June

Registration Review Decision

60-day Public Comment Period for Proposed Registration Review

Decision

2014-0ctober-December

Registration Review Decision and Begin Post-Decision Follow-u_Q_ 2015

Total (years) 2 years

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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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NEXT STEPS

As noted previously. the Agency will review the human health incident data and develop its Human 

Health Risk Assessment for metofluthrin. The Agency will review and respond to comments during 

the next phase of registration review, currently scheduled for June 2014. The Agency then will 

develop its proposed decision for the registration review of metofluthrin.