2 Fenbutatin-Oxide FINAL WORK PLAN

Introduction

This is the Environmental Protection Agency’s (EPA’s) Final Work Plan (FWP) for the registration review of fenbutatin-oxide. The FWP includes the expected registration

review timeline. The FWP also addresse s public comments received concerning the Preliminary Work Plan in the Summary Document , which was posted in the fenbutatinoxide registration review docket (EPA- HQ-OPP-2009-0841), and any other 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 new 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 R odenticide Act (FIFRA) standard for registration. Changes in science, public policy, and pesticide use practices will occur over time. The registration review program is intended to ma ke sure that, as the ability to assess risk evolves and as policies and pract ices change, all registered pe sticides continue to meet the statutory standard. The public phase of registration review begins when the initial docket is opened for each case. Inform ation on this program is provided at: http://www.epa.gov/oppsrr d1/registration_review/

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Fenbutatin-oxide is an organotin acaricide/insecticide currently registered for ornamental, recreational, agricultural and residential uses to control various insects such as thrips, whiteflies, mealy bugs, mites, and aphids. Fenb utatin-oxide is a rest ricted use pesticide due to ecological toxicity a nd, therefore, may only be appl ied by professional pesticide applicators. The mode of action for fenbut atin-oxide is the in hibition of oxidative phosphorylation (which affects energy production). There is one tech nical registration and two end-use product registrations containing fenbutatin-oxide.

Comments Received on Preliminary Work Plan

One comment was received on the fenbutatin-oxide Preliminary Work Plan (PWP) during the 60-day public comment period, which began on December 16, 2009 and closed on February 16, 2010. This comment di d not change the work plan or timeline

established in the PWP. In addition, through 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 comment period concerning these topics.3 Risk Assessment and Data Needs

Ecological Risk:

• The most recent ecological risk assessm ent was completed in August of 2007 in support of the fenbutatin-oxide Section 3 assessment for a new use on pistachios.

• The Agency has not conducted a risk assessment that supports a complete endangered species determination. The eco logical risk assessment planned during registration review will allow the Agen cy to determine whether the use of fenbutatin-oxide has “no effect” or “may affect” federally listed threatened or endangered species (listed species) or thei r 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.

• The Agency anticipates needing the fo llowing data in order to conduct an endangered species and non-target ecol ogical risk assessment for fenbutatinoxide.

o (GLN 835.4300) Aerobic Aquatic Metabolism

o (GLN 835.4400) Anaerobic Aquatic Metabolism

o (GLN 850.1730) Bioaccumulation in Fish

o (GLN 850.2100) Avian oral toxi city – Passerine species

o (GLN 850.1075) Freshwater fish – Acute toxicity

o (GLN 850.1010) Freshwater inve rtebrates – Acute toxicity

o (GLN 850.1350) Mysid chronic toxicity test

o (GLN 850.1400) Saltwater fish – Early life stage test

o (GLN 850.1735) Whole sediment toxici ty invertebrates, freshwater

o (GLN 850.1740) Whole sediment toxi city invertebrates, marine

o (GLN 850.4100) Terrestrial Plant toxi city Tier 1 seedling emergence

o (GLN 850.4150) Terrestrial Plant t oxicity Tier 1 vegetative vigor

o (GLN 850.5400) Aquatic Plant Growth: algae

o (GLN 850.4400) Aquatic Plant Growth: vascular plants

• For more information regarding the stat us and review of ecological fate and effects of fenbutatin-oxide, pl ease refer to the document: Registration Review: Problem Formulation for Ecological Risk, Environmental Fate, Endangered Species, and Drinking Water Assessmen ts for Fenbutatin-oxide (Vendex) in the fenbutatin-oxide registration re view docket (EPA-HQ-OPP-2009-0841)

.4 Human Health Risk:

• The most recent human health assessment for fenbutatin-oxide was completed in
2007 to establish a tolerance for fe nbutatin-oxide use on pistachios.

• Based upon the anticipated data requiremen ts, the toxicological endpoints may be revised during the registration re view of fenbutatin-oxide.

• The Agency anticipates conducting occupati onal handler and post-application risk assessments during the registration review of fenbutatin-oxide, which will incorporate any new hazard information.

• The Agency anticipates conducting a new aggregate assessment, which will only include food plus water, since residen tial exposures are not expected based on currently registered uses.

• The Agency’s residue chemistry database for fenbutatin-oxide is complete. However, the Agency anticipates re-calcu lating the dietary burden from animal feeding studies to reflect cu rrent methodology and policy.

• A new drinking water assessment will be conducted during registration review, which will include any updated hazard in formation, and will incorporate drinking water exposure values di rectly into the dietar y exposure assessment.

• Fenbutatin-oxide can only be applied at re sidential sites (to ornamental plants) by commercial applicators. The Agency does not anticipate conducting either a residential handler or post-application risk assessment during the registration

review of fenbutatin-oxide.

• The Agency anticipates requiring the fo llowing studies, in accordance with the revised 40CFR Part 158, to conduct a comprehensive human health risk assessment for the registration review of fenbutatin-oxide.

o (GLN 870.7800) Immunotoxicity

o (GLN 870.3465) 90-Day Inhalation Toxicity

o (GLN 870.7600) Dermal Absorption

o (GLN 870.6300) Developm ental Neurotoxicity Study

• The tolerance expression in 40CFR § 180.362(a), (b), and (c) will be reviewed during registration review to ensure that it appropriately covers the metabolites and degrades of fenbutatin oxide, and that it specifies the residues to be measured for each commodity. Any proposed revisions would be to the chemical description rather than the individual tolerance level(s).5 • For more information on the status and re view of the human health effects of fenbutatin-oxide, please refer to the document: Fenbutatin-Oxide: Registration Review Scoping Document for Human Health Assessments in the fenbutatin-oxide registration review docket (EPA-O PPTS-OPP-2009-00841) for a detailed discussion of previous human health assessments.

Timeline

EPA has created the following estimated ti meline for the completion of the fenbutatinoxide registration review.

Registration Review for Fenbutatin-Oxide

Projected Registration Review Timeline

Milestone Date Opening the Docket Open Docket & Public Comment Period for Fenbutatin-Oxide December 2009 Close Public Comment Period February 2010 Case Development Final Work Plan May 2010

Issue DCI Jan. – Mar. 2011

Data Submission Jan. – Mar. 2013 Open Public Comment for Preliminary RA Jul. – Sept. 2014

Close Public Comment Period Oct. – Dec. 2014 Registration Review Decision Open Public Comment for Proposed Regi stration Review Decision Jan. – Mar. 2015 Close Public Comment Period Apr. – June 2015 Final Reg. Review Decision and begin post-decision follow-up 2015

Total 6 years

Summary of Comments Receive d During Docket Opening

The fenbutatin-oxide registration review doc ket was open for a 60-day public comment period which began on December 16, 2009. Du ring that time, the FIFRA Endangered Species Task Force (FESTF) submitted a comment which is summarized below. The comment did not change the work plan or time line set out in the preliminary work plan. Consequently, this document makes final the work plan for the fenbutatin-oxide registration review process.

Comment from FESTF The FESTF submitted a comment requesting that any technical registrant for

fenbutatin-oxide who is not a member of the FESTF (or a company having met its data compensation obligati ons) be asked to provide a formal offer-to-pay to

FESTF for reliance on their data.6 EPA Response The Agency thanks FESTF for its comment and will consider this information as

it conducts the fenbutatin-oxide registration review process.

Next Steps

The Agency will develop a data call-in (DC I) notice for the data gaps listed under the

“Risk Assessment and Data Needs” section above.

Both an ecological risk assessment, wh ich will include an endangered species assessment, and a human health risk assessm ent will be conducted as detailed in the

“Risk Assessment and Data Needs” section above.