I NTRODUCTION

This is the Environm ental Protection Agency’s (EPA or the Agency ) Final Work Plan (FWP) for the registration review of cyhalofop

- butyl . This work plan addr esses public comments received concerning the Preliminary Work Plan (PWP) , which was posted in the cyhalofop

- butyl registration review docket (EPA

- HQ

- OPP

- 2014

- 0115 ). Cyhalofop

- butyl is an herbicide that is registered for use for grass weed control in rice only.

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 F IFRA 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. Informatio n on this program is provided on the Agency’s website

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The FWP begins with any update s 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 response s to th o se comments

. This section is followed by registration review planned data needs, risk assessments expected to be conducted , and the projected registration review timeline for cyhalofop

- butyl

. Lastly, there is a discussion of next steps.

UPDATES SINCE THE PWP WAS ISSUED

There are no additional updates on cyhalofop

- butyl since the PWP.

SUMMARY OF COMMENTS AND AGENCY RESPONSES

During the 60

- day public comment period on the cyhalofop

- butyl Preliminary Work Plan , which
open ed on September 24, 2014 and closed on November 24, 2014 the Agency received three (3) of public comments. Comments were submitted by Dow AgroSciences LLC, the Center for Biological Diversity (CBD), and the FIFRA Endangered Species Task Force ( FESTF ) . 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 about the PWP nor all of the Agency’s
responses. Summarized below are public comments that resulte d in changes to the anticipated registration review data needs, risk assessments, or timeline, or correct statements in the support documents for the PWP, or are of a broader regulatory nature. Public comments and EPA
responses in their entirety are locat ed in the docket, EPA

- HQ

- OPP

- 2014

- 0115 . Summarized public comments and Agency responses related to the ecological risk assessment are in the

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

2Cyhalofop

- butyl : Response to Public Comments on the Preliminary Ecological Risk Assessment for Registration Review of Cyhalofop

- butyl while those relevant to the growth of rice are in the BEAD Response to the Dow AgroSciences Comments on BEAD Memo on Use of Cyhalofop

butyl in Rice Production

. Comments submitted by Dow AgroSciences LLC in EPA

- HQ

- OPP

- 2 014

- 011 5

- 0022

. Comment: Dow AgroSciences (DAS) provided comments intended to address requests, errors, and inconsistencies found in the following EPA documents: 1) Cyhalofop

- butyl FOCUS Meeting Notes Recorded by M. Ranville; 2) Cyhalofop

- butyl FOCUS Meeting Notes Recorde d by J. Bloom; 3) Cyhalofop

- butyl Preliminary Work Plan; 4) Preliminary Ecological Risk Assessment for Registration Review of Cyhalofop

- butyl; 5) Cyhalofop

- butyl: Human Health Assessment Scoping Document in Support of Registration Review; 6) BEAD Chemical Profile for Registration Review: Cyhalofop

butyl; and 7) Rice Production Practices in the United States and Use of Cyhalofop

- butyl for Weed Control in Rice Production

Response: The comments presented by DAS provide clarifications and consistency to the do cuments listed above. The response to comments documents from the Environmental Fate and Effects Division (EFED) and Biological and Economical Analysis Division (BEAD) acknowledge general agreement with the comments of DAS on rice production practices and address /agree with DAS’ comments on the toxicity of cyhalofop

- butyl to aquatic invertebrates and terrestrial plants.

Comment: In the notes by M. Ranville from the FOCUS meeting, DAS disagrees with the following statements : “After the first crop is harvested, the field is drained and plowed. Then flooded again and ratoon crop might provide small second harvest. It would not be worth much to spray with herbicide and it would have to be planned well to meet the 60

- day PHI” It should be: After the first crop of rice is harvested, the field is dry. The field is re

- flooded to get the rice to start growing again. The field is not plowed between the first rice crop and the ratoon rice.

Response : The Agency agrees that after the har vesting of first crop, the rice field is dry. Soon after the harvest, pre

- flood nitrogen rate is applied and field is re

- flooded to stimulate the growth. Field is not plowed between rice crop and the ratoon rice. M ore information is found in 2012 Texas Ri ce Production Guidelines (see especially page 54 ), at http://varietytesting.tamu.edu/rice/varietyfiles/2012_Rice_Production_Guidelines.pdf

Comments submitted by CBD in EPA

- HQ

- OPP

- 2014

- 011 5

- 0017

. Comment : CBD ’s comments focus on the EPA’s independent duty under the Endangered Species Act (ESA) to consult with the U.S. Fish and Wildlife Service and the National Marine Fisheries Service (the Se rvices) on the registration review of cyhalofop

- butyl

. Response : EPA plans to address the concerns raised by CBD as part of the implementation plan for assessing the risks of pesticides to listed species, which will be based on the recommendations of t he April 2013 National Academy of Sciences (NAS) report. EPA will address concerns specific to cyhalofop

- butyl ’s effects on listed species in connection with the development of its registration review decision.

3At this time, EPA has not fully developed i ts risk assessment process for listed species. In November 2013, the EPA, along with the Services and the U.S. Department of Agriculture, released a summary of their joint Interim Approaches for assessing risks to listed species from pesticides. The Inte rim Approaches were developed jointly by the Agencies in response to the NAS recommendations and reflect a common approach to risk assessment shared by the Agencies as a way of addressing scientific differences between the EPA and the Services.

The NAS report, available at http://www.nap.edu/catalog.php?record_id=18344 , outlines recommendations on specific scientific and technical issues related to the development of pesticide risk assessment s that EPA and the Services must conduct in connection with their obligations under the ESA and FIFRA. The joint Interim Approaches were released prior to a stakeholder workshop held on November 15, 2013. In addition, the EPA presented the joint Interim A pproaches at the December 2013 Pesticide Program Dialogue Committee (PPDC) and State

- FIFRA Issues Research and Evaluation Group (SFIREG) meetings, allowing additional opportunities for stakeholders to comment on the Interim Approaches. As part of a phase d, iterative process for developing the Interim Approaches, the Agencies will also consider public comments on the Interim Approaches in connection with the development of upcoming Registration Review decisions. The details of the joint Interim Approache s are contained in the white paper “Interim Approaches for National

- Level Pesticide Endangered Species Act Assessments Based on the Recommendations of the National Academy of Sciences April 2013 Report,” dated November 1, 2013, available at http://www.epa.gov/espp/2013/nas.html

Comments submitted by FESTF in EPA

- HQ

- OPP

- 2014

- 0115

- 0016

. Comment: FESTF no ted that DAS is member of the task force and is entitled to make use of the FESTF database on species proximity to use s ites

. Response: The Agency is aware of the data developed by FESTF and will use th ose data to evaluate risks to listed species, as appropriate.

PLANNED DATA NEEDS

Table 1 below summarizes the planned data needs for cyhalofop

- butyl based on the Cyhalofop

- butyl. Human Health Assessment Scoping Document in Support of Registration Review

. The planned data needs have not changed from what was included in the PWP

.

Table 1: Planned D ata Needs for the cyhalofop

- butyl Registration Review

Guideline Number Study Title 2 Test Material Estimated Timeframe (Months from receipt of DCI)
870.3465 90

- day Inhalation Rat 2 T GAI 24 TGAI = technical grade active ingredient

2 Although the guideline is for a 90

- day study, a 28

- day study is considered adequate to satisfy the anticipated data requirement. The HASPOC concluded , based on weight

- of

- evidence considerations, that a sub chronic inhalation toxicity study is needed ; however, if the registrant can provide particle size distribution data for the granular product such that the Agency can determine what fraction of the product is both respirable and inhalable, the Agency could

re

- consider the need for the inhalation study.

4RISK ASSESSMENTS FOR REGISTRATION REVIEW

During registration review, the Agency anticipates the need to conduct a revised occupational handler risk assessment and will consider the potential for bystander volatilization assessments. If toxicological endpoints or points of departure are revised b ased on the data that are required for registration review, they will be considered in the new assessments, along with any changes to the standard operating p rocedures or default exposure assumptions

.

Table 2 below summarizes the planned registration review risk assessments based on the HED Scoping Document

, and the planned assessments have not changed from what was included in the PWP

. As noted in Table 2, EFED has already developed its preliminary risk assessment for cyhalofop

- butyl.

5Tab le 2: Planned Risk Assessments for the C yhalofop

- butyl Registration Review
Type of Risk Assessment Conduct ? Notes
Eco logical and Environmental Fate Comprehensive ecological (species to be assessed include terrestrial and aquatic organisms), including an assessment of risks to threatened and endangered species H as been conducted The Agency has already developed and released its Preliminary Ecological Risk Assessment for Registration Review of Cyhalofop

- butyl. The Agency was able to develop the risk ass essment because the existing database is sufficient to support an
assessment without the receipt and consideration of new data

. Based on currently registered uses and labeled rates, the preliminary assessment identifies potential risks to some non

- target organisms. An endangered species assessment has not been conducted at this time. Incidents Will check for updates Four ecological incidents have been reported for cyhalofop

- butyl ; see page 29 of the risk assessment. The Agency will continue to monitor i ts incident databases. Human Health Dietary Food No Unless needed due to any updates to points of departure or exposure estimates from the diet

. The dietary exposure database is adequate to support the existing registrations. Dietary risks estimate d for the 2012 assessment were not of concern. Drinking water No Unless needed due to any updates to points of departure or exposure estimates from drinking water. D rinking water risks estimated for the 2012
assessment were not of concern. Occupational Handlers (mixers, loaders, applicators) Yes A handler inhalation assessment will be needed to account for inhalation toxicity or particle size distribution data. Post

- application No A dermal endpoint has not been identified for cyhalofop

- butyl, so an occupational post

- application risk assessment is not needed

. Residential Handlers No There are no residential handler scenarios for cyhalofop

- butyl. Post

- application Yes During registration review, the Agency will consider the potential for inhalation exposure to bystanders through volatilization. Other Aggregate No Because there are no residential uses of cyhalofop

butyl, an aggregate assessment is not needed

.

6Table 2: Planned Risk Assessments for the Cyhalofop

- butyl Registration Review Cumulative No EPA has not made a common mechanism of toxicity finding as to cyhalofop

- butyl and any other substances

, and cyhalofop

- butyl does not appear to produce a toxic met abolite produced by other substances. Tolerances No The re are no Codex Alimentarius Commission (Codex) or Canadian maximum residue limits (MRLs) for cyhalofop

- butyl. As a result, there are no harmonization issues at the present time. Incidents Will check for updates For a discussion of reported human incidents for cyhalofop

- butyl, see page 10 of the Scoping Document and the Cyhalofop

- butyl : Tier I Review of Human Incidents

. Based on the low frequency and severity of reported incident s , there does not appear to be a concern at this time that would warrant further investigation.

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

- butyl registration review in Table 3 below

. The projected time line has not changed since the PWP.

Table 3: Registration Review for Cyhalofop

- butyl

– Projected Registration Review Timeline Activities Estimated Date Opening the Docket Open Docket and 60

- day Public Comment Period Sept. 2014

– Completed Close Public Comment Nov. 2014

– Completed Case Development Final Work Plan Mar. 2015

- Completed Issue DCI April

- June 2015 Data Submission April

- June 2017 60

- day Public Comment Period for Draft Risk Assessments 3 1] Oct.

– Dec. 2018 Registration Review Decision 60

- day Public Comment Period for Proposed Registration Review Decision July

– Sept. 2019

Registration Review Decision and Begin Post

- Decision Follow

- up 2020 Total (years) 6

NEXT STEPS As noted previously, the Agency plans to require data to support a human health risk assessment for cyhalofop

- butyl through a D ata C all

- I n Notice , expected to be issued in April

- June of 2015

.

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 conventi onal pesticides, the Agency plans to provide a 60 calendar day public comment period generally for draft risk assessments.

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