2 Introduction

This is the Environmental Protection Agency’s (EPA or the Agency) Final Work Plan (FWP) for the registration review of flufenacet. The Final Work Plan includes the expected registration review timeline. The FWP also a ddresses public comments received concerning the Preliminary Work Plan (PWP) in the Summary Document which was posted in the flufenacet registration review docket (E PA-HQ-OPP-2010-0863) and any ot her comments concerning the initial docket postings. The Summary Document provided information on what EPA knows about the pesticide and what additional risk analyses and data or information the Agency

believes are needed to make a registration review decision.

The Agency is implementing the registra tion review program and will review each registered pesticide every 15 years to determin e whether it continues to meet the Federal Insecticide, Fungicide, and Rode nticide Act (FIFRA) standard for registration. Changes in science, public policy, and pestic ide use practices occur over time. The registration review program is intended to make sure that, as the ab ility to assess risk evolves and as policies and practices change, all registered pesticides contin ue to meet that statutory standard. The public phase of registration review begins when the ini tial docket is opened for e ach case. Information on this program is provided at http://www.epa.gov/oppsrrd1/registration_review/

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Flufenacet (case number 7245) is an oxyacetamid e herbicide registered for use on wheat (including triticale), perennial gra sses grown for seed, corn (field and sweet), soybeans, and fir trees (FIFRA 24(c) Special Local Need (SLN) in Washington and Oregon only). Flufenacet is not registered for homeowner use, and there are currently no uses e xpected to result in residential exposure. Flufenacet was first registered in 1993 and therefore was not subject to the reregistration process under FIFRA.

This document makes final the work plan for the flufenacet registrati on review processes.

Comments Received on Preliminary Work Plan

On March 30, 2011 EPA opened a 60-day pub lic comment period for the registration review of flufenacet. The comment period en ded on May 31, 2011. The Preliminary Work Plan

document can be located in the flufenacet re gistration review docke t (EPA-HQ-OPP-2010-0863)

at www.regulations.gov

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During the public comment period, the Agency received comments from Bayer CropScience (Bayer) and the FIFRA Endangered Species Task Force (FESTF). A detailed description of the Bayer comments as well as the Agency’s response to these comments is available in separate response memoranda from the Agency’s Environmental Fate and Effects Division (EFED) and Human Health Effects Divisi on (HED), which are locat ed in the flufenacet registration review docke t (EPA-HQ-OPP-2010-0863) at www.regulations.gov . The Agency’s response to FESTF’s comment is below. The co mments received do not change the anticipated

data and risk assessment needs that were de scribed in the PWP and the timeline remains unchanged. The anticipated data and risk assessment needs are detailed below.3 In the PWP, EPA solicited comments on three specific topics: environmental justice, water body impairment and trade irritants. No comments or information were received during the public comment period concerning these issues.

Comment from FESTF

In June of 2004, March of 2005, and Octobe r 19, 2007, the FIFRA Endangered Species Task Force (FESTF) submitted its Information Management System ( FESTF Information Management System (IMS): Documentati on of Structure and Function of IMS 1.1, MRID #46325901) and documentation of the beta-tes ted IMS, NatureServe data ( FESTF Task Force Information Management System (IMS): Beta-T ested IMS 2.0 and Access to NatureServe Data - Final Report , MRID #46486301) and NatureServe Data Evaluation and Review (MRID #47260101). These data fulfill the data requirements spelled out in Pesticide Registration Notice 2000-2 and provide the best availabl e data necessary for the proxim ity analysis of Flufenacet use and listed species locations. The leading registrant , as identified on the fact sheet included in the Registration Review Summary, is Bayer CropScience (Bayer), a FESTF member. Bayer is entitled to rely on FESTF data.

Agency Response

The Agency thanks FESTF for its comment, and will consider this information as it conducts the registration review and ma kes its registration review decision.

Anticipated Risk Assessment and Data Needs

The Agency anticipates conducting a comp rehensive ecological risk assessment, including an endangered species a ssessment, for all pesticide uses of flufenacet. The Agency also anticipates conducting a human health risk assessment. Belo w is a summary of the issues relevant to the registration review of flufenacet.

Ecological Risk

A summary of the anticipated risk assessm ent and data needs for the ecological and endangered species assessments follows:

 The Agency has not conducted a risk asse ssment that supports a complete endangered species determination for flufenacet. The ecological risk assessment planned during registration review will allow the Agency to determine whether flufenacet’s use has “no effect” or “may affect” federally liste d threatened or endangered species (listed species) or their designated crit ical habitants. 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 a nd Wildlife Service and/or National Marine Fisheries (the Services), as appropriate.

 The Agency anticipates requiring the followi ng data in order to conduct a complete ecological risk assessment for flufenacet.4 o GLN 835.6100 (footnote 7) Environmental Chemistry Methods (ECM) for Soil with Independent Laboratory Validation (ILV)

o GLN 835.6200 (footnote 7) Environmental Chemistry Methods (ECM) for Water and Sediment with Independent Laboratory Validation (ILV)

o GLN 850.1035 Estuarine/marine Inve rtebrate Acute Toxicity Test

o GLN 850.1350 Mysid Chronic Toxicity Test

o GLN 850.1400 Estuarine/Marine Fi sh Early Life Stage Test

o GLN 850.2100 Acute Oral Avian To xicity Test (Passerines)

o GLN 850.4100 Seedling Emergence, Tier II (Axiom DF end-use product)

o GLN 850.4150 Vegetative Vigor, Tier II (Axiom DF end-use product)

o GLN 850.4400 Aquatic vascular plant toxicity, Tier II (Thiadone, degradate of flufenacet)

 Please refer to the document, Revised: Registration Review – Preliminary Problem Formulation for Ecological Risk and Environmental Fate; Endangered Species, and Drinking Water Assessments for Flufenacet (February 3, 2011) , located in the docket, for a detailed discussion of the anticipated ecological risk assessment and data needs.

Human Health Risk:

A summary of the anticipated risk assessm ent and data needs for the human health

assessment follows:

 The Agency anticipates conducting a new dietary assessment for the purpose of registration review to inco rporate a revised drinking wa ter assessment, which will include the thiadone degradate.

 The Agency will consider the existing toxi city database as well as all additional toxicity studies received during registration review and will re-evaluate the sensitivity determination, as well as the points of depa rture and safety factors, used for risk

assessment purposes.

 Flufenacet is not currently registered for use in residential settings. Therefore, residential exposure to flufenacet is not e xpected. However, if exposure data and methodologies for estimating exposure have ch anged for issues such as volatilization, spray drift and track-in from fi eld applications to residential settings at the time of the draft registration review assessment, then the Agency would anticipate requiring a residential exposure assessment.

 The Agency anticipates conducting a re vised occupational assessment during registration review. The following scenario s have not been assessed under current occupational residential exposure (ORE) po licies and will be added to the revised occupational assessment:5 o New mixer/loader, applicator, and flagger assessments will be needed for the aerial application of flufenacet on fir trees.

o New mixer/loader occupational risk assessments will be needed to incorporate the liquid formulation of flufenacet for corn (field and sweet), soybeans, wheat (and triticale).

 The Agency is currently evaluating the March 2, 2010 Scientific Advisory Panel (SAP) final report on issues related to vol atilization of pesticides and may, as appropriate, develop policies and procedures to identify whether to incorporate postapplication inhalation exposur e into the Agency’s risk assessment, and methods to assess post-application inhala tion exposure. If new po licies or procedures are implemented, the Agency would anticipate revisiting the need for a quantitative occupational post-application inhalati on exposure assessment for flufenacet.

 The tolerance expression in 40 CFR § 180.527 will be reviewed during registration

review to ensure that it a ppropriately covers flufenacet and its metabolites containing

the 4-fluoro- N -methylethyl benzenamine moiety and that it specifies the residues to be measured for each commodity.

 The Agency anticipates requiring the followi ng data in order to conduct a complete

human health risk assessment for flufenacet:

o GLN 870.7800 Immunotoxicity Study

o Special Study -- Comparative Thyroid Assa y (CTA) is anticipated to be required because available data support the possibili ty of decreases in thyroid hormones at dose levels similar to those used in the submitted developmental neurotoxicity (DNT) study, as well as increases in neurobehavioral and neuropathological findings in multiple species.

 Please refer to the document, Flufenacet. Human Health Assessment Scoping Document in Support of Registration Review (January 21, 2011) , located in the docket, for a detailed discussion of the anticipated ri sk assessment and needs for human health.

Changes to Data Needs:

The Agency has received a third bridgi ng study to support GLN 830.1500 Bridging Study Supporting Postemergence Application Uses of Soluble Concentrate (S C) Formulation. The study is currently in review.

Recently, the Agency decided to no l onger require GLN 830.7050, UV/Visible light absorption during registration revi ew. These data were helpful dur ing product reregistration, as they pertain to the structural analysis of the active ingredie nt. However, the data are not necessary for the registration review process because they do not conc ern human health or

environmental effects.6 Endocrine Disruptor Screening Program:

As required by FIFRA and FFDCA, EPA review s numerous studies to assess potential adverse outcomes from exposure to chemicals. Collectively, these studies include acute,

subchronic and chronic toxici ty, including assessments of carcinogenicity, neurotoxicity, developmental, reproductive, and general or syst emic toxicity. These studies include endpoints which may be susceptible to endocrine influenc e, including effects on endocrine target organ histopathology, organ weights, es trus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, and sex ratios in offspring. For ecological hazard asse ssments, EPA evaluates

acute tests and chronic studies that assess growth, developmen tal and reproductive effects in different taxonomic groups. As part of its most recent registration decision, EPA reviewed these data and selected the most sensitive endpoints fo r relevant risk assessment scenarios from the existing hazard database. However, as require d by FFDCA section 408(p), flufenacet is subject to the endocrine screening pa rt of the Endocrine Disruptor Screening Program (EDSP).

EPA has developed the EDSP to determine whether certain substances (including pesticide active and other ingredie nts) may have an effect in hu mans or wildlife similar to an effect produced by a “naturally occurring estr ogen, 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 w ith 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 th e next stage of the EDSP where EPA will determine which, if any, of the Ti er 2 tests are necessary based on the available data. Tier 2 testing is designe d to identify any adverse endocr ine-related effects caused by the substance, and establish a dose-response relations hip 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 pest icide active ingredients and 9 inert ingredients. Flufenacet is not among the group of 58 pesticide active ingredient s on the initial list to be screened under the EDSP. Accordingly, as part of registration review, EPA will issu e future EDSP orders/data callins, requiring the submission of EDSP screening assays for flufen acet. For further information on the status of the EDSP, the policies and procedur es, the list of 67 chemicals, future lists, the test guidelines and the Tier 1 screen ing battery, please visit our website: http://www.epa.gov/endo/

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Timeline:

EPA has created the following estimated time line for the completion of the flufenacet registration review.7 Registration Review for Flufenacet – Projected Registration Review Timeline

Activities Estimated Date Opening the docket Open Docket and Public Comment Period 2011 – March Close Public Comment 2011 – May Case Development Final Work Plan 2011 – August Issue DCI 2012 – April – June Data Submission 2014 – April – June Open Public Comment Period for Preliminary Risk Assessments 2015 – Oct. – Dec.

Close Public Comment Period 2016 – Jan. - March Registration Review Decision Open Public Comment Period for Proposed Regist ration Review Decision 2016 – April - June Close Public Comment Period 2016 – July – Sept. Registration Review Decision and Be gin Post-Decision Follow-up 2017 Total (years) 6

Next Steps

The Agency plans to issue a Data Call-In (D CI) for flufenacet in 2012. The new data will

be used to conduct the risk assessments out lined in this FWP for all flufenacet uses.