Docket Number; EPA–HQ–OPP–2009–0618 www.regulations.gov

United States Prevention, Pesticides March 2010

Environmental Protection and Toxic Substances Agency (7510P)



# 10,10'-Oxybisphenoxarsine (OBPA)

Final Work Plan Registration Review March 2010Docket Number; EPA-HQ-OPP-2009-0618 www.regulations.gov

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### TABLE OF CONTENTS

OBPA Registration Review Team Members.............................................. 4

I. Introduction.................................................................................... 5 II. Comments on Preliminary Work Plan................................................. 5

III. Risk Assessment and Data Needs...................................................... 6

IV. Timeline...................................................................................... 9 V. Glossary of Terms a nd Abbreviations.................................................. 10Docket Number; EPA-HQ-OPP-2009-0618 www.regulations.gov

4 10,10'-Oxybisphenoxarsine (OBPA 

## ) Registration Review Team

Human Health & Environmental Effects

Tim McMahon Najm Shamim

Risk Management
Monisha Harris
Lance Wormell

Office of General Counsel Philip RossDocket Number; EPA-HQ-OPP-2009-0618 www.regulations.gov

5 I. Introduction

This is EPA’s Final Work Plan (FWP) fo r the registration review of OBPA. The work plan includes the expect ed registration review timelin e. The work plan also addresses public comments received concerni ng the Preliminary Work Plan (PWP) in the Summary Document which was posted in the OBPA registration review docket, and any other comments concerning the initial doc ket 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 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 de termine whether it continues to meet the FIFRA standard for registration. The Agency will consider benefits information and data as required by FIFRA. Changes in science, public policy and pesticide use practices will occur over time. The registration review progr am is intended to make sure that, as the ability to assess risk evolves and as policies a nd practices change, all registered pesticides

continue to meet that statutor y standard. The public phase of registration review begins when the initial docket is opened for each case. Information on this program is provided

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

.

The OBPA Preliminary Work Plan wa s published September 23, 2009. The 90-day comment period ended on December 22, 2009. Th e Preliminary Work Plan document is

available on www.regulations.gov , docket number EPA-HQ-OPP-2009-0618.

II. Comments Received on Preliminary Work Plan:

EPA received one comment during the public comment period on the initial docket, described below.

In the PWP, EPA also solicited comments on three specific topics: environmental justice; water body impairment; and trade irr itants. No comments or information were received during the public comment period concerning these issues.

During the public comment period, the EP A received one comment as described and discussed below. The comment received during the initial public comment period did not affect the data needs, work plan and timeline described in the PWP and they remain as they were presented initially in the PWP. Further, this document makes final the work plan for the OBPA registration review process.

Comment: The FIFRA Endangered Species Task Force (FESTF) submitted a comment requesting that any technical registrant fo r OBPA who is not a member of the FESTF (or a company having met its data compensation ob ligations) be asked to provide a formal offer-to-pay to FESTF for reliance on their data. In their comment, FESTF also noted that Akcros Chemicals, Inc., Rohm and Ha ss Company and Troy Chemical Company are the leading registrant for OBPA, and that the above mentioned are not FESTF members.Docket Number; EPA-HQ-OPP-2009-0618 www.regulations.gov

6 Therefore, the technical registrant must offer to pay FESTF to rely on FESTF submitted data or develop substantial similar data on their own.

Response: The Agency thanks FESTF for its comment and will consider this information as it conducts the registra tion review and makes its registration

review decisions.

III. Risk Assessment and Data Needs

A Reregistration Eligibilit y Decision was completed for OBPA in June 1993. However, to complete registration review, additional data are needed to conduct the human health and ecological risk assessments.

Human Health Risk

The Agency reviewed the hazard and exposur e databases for OBPA as part of this registration review case. As a result of this review, EP A anticipates that additional toxicity and exposure data will be needed to complete registration review. Toxicology data are needed to address subchronic, deve lopmental, and reproductive toxicity as well as mutagenic potential. In addition, metabo lism data are needed to characterize the disposition and biotransformation of OBPA in vivo

.

EPA believes risk assessments are needed to ensure that the OBPA registration review case meets the safety standards establis hed by FFDCA, as amended by FQPA. The Agency intends to complete the human heal th risk assessments presented below. Further information and detailed justifications for the required studies are available in the document titled “10,10’ Oxybisphenoxarsi ne (OBPA): Human Health Assessment Scoping Document in Support of Registra tion Review” (dated August 20, 2009).

• Residential risk assessment (adults and children) following us e/application of products made from preserved material s (e.g., pool liners, vinyl flooring, and mattress covers).

• Occupational handler inhalation risk assessment to estimate potential risks associated with mixing/loading and handling OBPA during manufacture of plastics or technical and formul ated products containing OBPA.

• An aggregate exposure and risk asse ssment may be needed for OBPA depending on the submission and review of any toxicology studies required

for OBPA and the formal evaluation of routes and magnitude of anticipated human exposures.

Dietary and Drinking Water Assessment

The Agency does not expect any direct or indirect dietary expos ure to occur from the current use patterns for OBPA produc ts; therefore, EPA does not anticipate conducting a dietary and drinki ng water risk assessment.Docket Number; EPA-HQ-OPP-2009-0618 www.regulations.gov

7 Occupational and Resi dential Assessment

Because currently registered uses of OB PA may result in both residential and occupational exposure, the Agency will conduct a residential risk assessment and an occupational risk assessment. Plastics containing OBPA (e .g., polyvinylchloride, polyurethane, and ethylene-vinylacetate copoly mer plastics) are fabricated into numerous items – including shower curtains, floor coveri ngs, carpets, ditch liners, coated fabrics (including mattress covers), marine upholstery, tarpaulins, gaskets, weather stripping, shoe soles, and swimming pool liners – that may result in residentia l and/or occupational

exposure.

Anticipated Human Health Data Needs

The review of the existing toxicological database for OBPA showed that many of the studies have significant deficiencies th at do not allow adequate characterization of hazard, and that other studies are not availa ble that would be required to adequately

characterize risk for OBPA based on current us e patterns. Therefore, for the purposes of registration review, anticipa ted toxicology data needs for OBPA are as follows:

Anticipated OBPA Human Health Toxicity Data Needs:

• (GLN 870.1300) Acute Inhalation Toxicity-rodent

• (GLN 870.3100) 90-Day Or al Toxicity-rodent

• (GLN 870.3250) 21-Day Dermal Toxicity-rodent

• (GLN 870.3700) Developmental Toxicity- rodent

• (GLN 870.3800) Reproductive Toxicity- rodent

• (GLN 870.7485) General Metabolism-rodent*

• (GLN 870.5265) Salmonella typhimurium reverse mutation assay

• (GLN 870. 5300) Mammalian cells in culture

• (GLN None) In vivo cytogenetics

*With respect to the metabolism data requirements, a dual radiolabeled test substance would need to be tested. Specifically, the arsenic portio n of the molecule would need to be labeled as well as the aromatic portion of the molecule to adequately determine metabolites and tissue distribution.

Anticipated OBPA Occupational/Resid ential Exposure Data Needs

• (GLN 875.1200) Dermal indoor exposure

• (GLN 875.1400) Inhala tion indoor exposure

• (GLN 875.1600) Data repor ting and calculations

• (GLN 875.1700) Product use information

• (GLN None) Leaching studies for pool lin ers, vinyl flooring, and mattress covers*

*To properly assess exposure from pool liners, vinyl flooring, and mattress covers (which are representative of the highest exposu res), the Agency expects to requir e leaching studies for each matrix. Since a guideline and associated protocol are not currently available, registrants likely will be required to submit a protocol to EPA for review prior to initiating the study.Docket Number; EPA-HQ-OPP-2009-0618 www.regulations.gov

8 Ecological Risk

The Agency reviewed the environmental fate and ecological hazard databases for OBPA. Based on its review, EPA believes risk assessments are needed to ensure that the OBPA registration review case meets the FI FRA standards. For OBPA, the Agency anticipates needing some of the environm ental fate and ecological effects data requirements listed for OBPA in order to c onduct the environmenta l fate and ecological risk assessments, including an endangered species assessment. Further information and detailed justifications for the studies that ar e expected to be required are available in the document titled “Summary of Product Chemis try, Environmental Fate, and Ecotoxicity Data for the 10,10'-Oxybisphenoxarsine Regist ration Review Decisi on Document” (dated August 10, 2008).

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 Agency to determine whether OBPA’s use has “no effect” or “may affect” federally listed threat ened or endangered sp ecies (listed species) or their designated critical ha bitats. When an assessment c oncludes that a pesticide’s use “may affect” a listed species or its designate d critical habitat, the Agency will consult

with the U.S. Fish and Wildlife Service and/ or National Marine Fisheries Services (the Services), as appropriate.

Anticipated Environmental Fate and Ecological Data Needs

The Agency anticipates conducting envi ronmental fate and ecological risk assessments for material preservatives that potentially pass through waste water treatment plants (WWTPs) and may be discharged into terrestrial and aqua tic environments. Therefore, the Agency anticipates requiring th e environmental fate and ecotoxicity data identified below for OBPA and/or any of its major degradation products that are of potential concern for all registered uses of OBPA. The following environmental fate and ecotoxicity data are needed to conduct an environmental fate and ecological risk

assessment:

Anticipated OBPA Environmental Fate Data Needs

• (GLN 835.2120) Hydrolysis

• (GLN 835.2240) Photodegradation in water

• (GLN 850.6800) Modified activated sludge respiration inhibition

• (GLN 835.1110) Activated sl udge sorption isotherm

• (GLN 835.3110) Ready biodegradability

• (GLN None) Leachability of OBPA fro m polyvinyl chloride (PVC) swimming pool liner and a film of vinyl baby pants*

* Since a guideline and associated protocol are not curr ently available, registrants likely will be required to submit a protocol to EPA for review prior to initiating the study.Docket Number; EPA-HQ-OPP-2009-0618 www.regulations.gov

9 Anticipated OBPA Ecological Data Needs

• (GLNs 850.4400 & 850.5400) algal toxicity (Tie r II) using freshwater green alga, Selenastrum capricornutum

Product Chemistry Status and Anticipated Data Needs

All product chemistry data requirements have been satisfied for the active ingredient OBPA. Therefore, the Agency does not anticipate the need to require additional product chemistry data for OBPA at this time.

IV. Timeline

EPA has created the following estimated timeline for the completion of the OBPA registration review case.

Anticipated Schedule

Activities Estimated Month/Year Phase 1: Opening the docket
Open Public Comment Period for OBPA Docket Completed September 2009
Close Public Comment Period Completed December 2009
Phase 2: Case Development

Develop Final Work Plan (FWP) March 2010

Issue DCI March 2011

Data Submission March 2013
Open Public Comment Period for Preliminary Risk Assessments September 2014

Close Public Comment Period December 2014

Phase 3: Registration Review Decision
Open Public Comment Period for Pro posed Reg. Review Decision March 2015

Close Public Comment Period June 2015 Final Decision and Begin Post-Decision Follow-up 2015 Total (years) 6

Next Steps

The Agency plans to develop a Data Call-In fo r this pesticide and expects to issue it in

December 2011.Docket Number; EPA-HQ-OPP-2009-0618 www.regulations.gov

10 III. GLOSSARY of TERMS & ABBREVIATIONS

ai Active Ingredient AR Anticipated Residue ASTM American Society for Testing and Materials

AWPA American Wood Preserver’s Association

CBI Confidential Business Information CFR Code of Federal Regulations cPAD Chronic Population Adjusted Dose

CSF Confidential Statement of Formula CSFII USDA Continuing Surveys for Food Intake by Individuals

DCI Data Call-In DEEM Dietary Exposure Evaluation Model DFR Dislodgeable Foliar Residue DNT Developmental Neurotoxicity DWLOC Drinking Water Level of Comparison

EC Emulsifiable Concentrate Formulation EDWC Estimated Drinking Water Concentration

EEC Estimated Environmental Concentration

EP End use Product EPA Environmental Protection Agency

EUP End-Use Product FDA Food and Drug Administration FIFRA Federal Insecticide, Fungicide, and Rodenticide Act FFDCA Federal Food, Drug, and Cosmetic Act FQPA Food Quality Protection Act FOB Functional Observation Battery GENEEC Tier I Surface Water Computer Model

IR Index Reservoir

LC 50 Median Lethal Concentration. A statistically derived concentration of a substance that can be expected to cause death in 50% of test animals. It is usually expressed as the weight of substance per weight or volume of water, air or feed, e.g., mg/l, mg/kg or ppm.

LD 50 Median Lethal Dose. A statistically deri ved single dose that can be expected to

cause death in 50% of the test animals when administered by the route indicated (oral, dermal, inhalation). It is expressed as a weight of substance per unit weight of animal, e.g., mg/kg.

LOC Level of Concern

LOAEL Lowest Observed Adverse Effect Level μg/g Micrograms Per Gram μg/L Micrograms Per Liter mg/kg/day Milligram Per Kilogram Per Day mg/L Milligrams Per Liter MOE Margin of Exposure

MRID Master Record Identifi cation (number). EPA's system of recording and tracking

submitted studies. MUP Manufacturing-Use Product NA Not Applicable NAWQA USGS National Ambient Water Quality Assessment NPDES National Pollutant Discharge Elimination System NR Not Required

NOAEL No Observed Adverse Effect Level OPP EPA Office of Pesticide Programs OPPTS EPA Office of Prevention, Pesticides and Toxic Substances PAD Population Adjusted DoseDocket Number; EPA-HQ-OPP-2009-0618 www.regulations.gov

11 PAIRA Pure Active Ingredient Radiolabelled PCA Percent Crop Area PDP USDA Pesticide Data Program PHED Pesticide Handler's Exposure Data

PHI Preharvest Interval phr Pounds Per Hundred ppb Parts Per Billion PPE Personal Protective Equipment ppm Parts Per Million PRZM/EXAMS Tier II Surface Water Computer Model Q 1 * The Carcinogenic Potential of a Compound, Quantified by the EPA's Cancer

Risk Model RAC Raw Agriculture Commodity RED Reregistration Eligibility Decision REI Restricted Entry Interval

RfD Reference Dose RQ Risk Quotient RTU Ready to Use SCI-GROW Tier I Ground Water Computer Model SAP Science Advisory Panel SF Safety Factor SLN Special Local Need (Registrati ons Under Section 24©) of FIFRA) TGAI Technical Grade Active Ingredient TEP Typical End-Use Product USDA United States Department of Agriculture UF Uncertainty Factor

WPS Worker Protection Standard