1 Docket Number EPA

- HQ

- OPP

- 2010

- 1006 www.regulations.gov



## Dioctyl Sodium Sulfosuccinate Final Work Plan

Registration Review

April 20113 DIOCTYL SODIUM SULFOSUCCINATE FINAL WORK PLAN

Introduction

This is the Environmental Protection Agency’s (EPA’s) Final Work Plan for the registration review

of Dioc tyl sodium sulfosuccinate (DSS) . This work plan includes the expected registration review timeline. The work plan also addresses public comments received concerning the Preliminary Work

Plan in the Summary Document , which was posted in the DSS registration review docket ( EPA

HQ

- OPP

- 2010

- 1006 ), and any other comments concerning the initial docket postings. The Summary Document provided information on what E PA 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 Federa l 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 w ill 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 registr ation 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/

.

Dioctyl sodium sulfosucc inate (DSS) is the active ingredient in pet shampoos and spray products, which are registered in combination with undecylenic acid. As a pesticidal active ingredient, there

are no food uses and there are no tolerances established for DSS. DSS is also us ed as an inert ingredient in multiple end

- use pesticide products for agricultural and non

- agricultural areas; in disinfectants and sanitizers used in residential and commercial settings; and as a wetting agent in industrial, drug, cosmetic, and food produc ts. Some of the drug products contain DSS for use as a stool softener and laxative. As an inert ingredient there are exemptions from the requirement of a

tolerance established for the sodium salt of DSS under 40 CFR 180.910 and 40 CFR 180.930. These

exe mptions allow DSS as an inert ingredient to be used in pesticide formulations for pre

- and post

harvest application to crops and direct application to livestock

.

DSS was first registered as an active ingredient in 1995. Therefore, a Reregistration Elig ibility Decision (RED) document was not completed for DSS. For registration review only the use of DSS as an active ingredient (in pet shampoos) will be considered. Its use as an inert ingredient will be

considered in the risk assessments for those activ e ingredients with which it is formulated. In any case, the non

- pesticidal uses of DSS are expected to dominate both human and wildlife exposure to

this chemical.4 Comments Received on Preliminary Work Plan :

No comments were received during the 60

- day p ublic comment period on the planned ecological assessment and human health scoping document discussed in the Preliminary Work Plan . In the Preliminary Work Plan , EPA also solicited comments on three specific topics: environmental justice, water body impa irment, and trade irritants. No comments or information were received during the comment period concerning these three topics.

Anticipated Risk Assessment and Data Needs

The Agency does not intend to require additional data on dioctyl sodium sulfosuc cinate. The Agency plans to conduct a comprehensive ecological risk assessment, including an endangered species risk assessment, for the pesticidal uses of dioctyl sodium sulfosuccinate

. Below is a summary of the issues relevant to the registration revi ew of dioctyl sodium sulfosuccinate.

Ecological Risk:

**•** No ecological risk assessment has been c omplet ed for DSS as pesticidal active ingredient.

DSS was evaluated as an inert ingredient in June, 2006. The review of DSS as an inert ingredient did not i dentify any ecological risks of concern to fish

.

**•** The Agency has not conducted an ecological risk assessment that supports a complete endangered species determination for dioctyl sodium sulfosuccinate. The ecological risk assessment planned during registr ation review will allow the Agency to determine whether dioctyl sodium sulfosuccinate ’s use has “no effect” or “may affect” federally listed threatened or endangered species (listed species) or their designated critical habitats. When

an assessment conclu des 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 ( FWS )

and/or National Marine Fisheries Service (NMFS) (the Services), as appropriate.

**•** D ue to the n ature of DSS as a shampoo use on pets, mammals, and reptiles, no data are needed. In addition, because DSS as an active ingredient is registered for indoor uses and according to the updated data requirements in 40 CFR part 158, it is anticipated that no

a dditional ecological data are required for the indoor uses.

Please refer to the “ Registration Review

– Preliminary Problem Formulation for the Ecological Risk and Drinking Water Exposure Assessments for Dioctyl Sodium Sulfosuccinate ,” dated December
20, 2 010, for a more detailed discussion of the anticip ated ecological risk assessment

.5 Human Health Risk:

**•** No human health risk assessment has been completed for DSS as a conventional pesticide active ingredient.

**•** Because of the extensi ve literature data ava ilable on DSS, its low toxicity, FDA’s approval of the chemical as a drug for use at much higher doses than would be experienced as a result of pesticide

- related uses, and the chemical’s classification by FDA as Generally Recognized as Safe (GRAS) (21 CFR 178.3400), the Agency concludes that additional toxicity data are not required

.

**•** A quantitative human health risk assessment is not required under registration review for the existing uses of DSS. There are no risks of concern associated with DSS. No die tary or residential exposure assessment or aggregate risk assessment is required.

**•** DSS is exempted from the requirement s of tolerance s under 40 CFR 180.910 and 180.930. No residue chemistry data is required for DSS.

Please refer to the “ Dioctyl Sodium Su lfosuccinate. Human Health Assessment Scoping Document

in Support of Registration Review,” dated December 16, 2010 located in the docket for a detailed

discussion of the human health risk assessment status.

Endocrine Disruptor Screening Program

As requir ed by FIFRA and FFDCA, EPA reviews numerous studies to assess potential adverse outcomes from exposure to chemicals. Collectively, these studies include acute, subchronic and chronic toxicity, including assessments of carcinogenicity, neurotoxicity, devel opmental, reproductive, and general or systemic toxicity. These studies include endpoints which may be susceptible to endocrine influence, including effects on endocrine target organ histopathology, organ weights, estrus cyclicity, sexual maturation, ferti lity, pregnancy rates, reproductive loss, and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and chronic studies that assess growth, developmental and reproductive effects in different taxonomic groups. As part of its reregistration decision , EPA reviewed these data and selected the most sensitive endpoints for relevant risk assessment scenarios from the existing hazard database. However, as required by FFDCA section 408(p), methomyl is subject to the endocrine scr eening part of the Endocrine Disruptor Screening Program (EDSP).

EPA has developed the EDSP to determine whether certain substances (including pesticide active and other ingredients) may have an effect in humans or wildlife similar to an effect produced by a “naturally occurring estrogen, 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 ident ify the potential of a chemical substance to6 interact with 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 p roceed to the next stage of the EDSP where EPA will determine which, if any, of the Tier 2 tests are necessary based on the available data. Tier 2 testing is designed to identify any

adverse endocrine

- related effects caused by the substance, and establish a dose

- response relationship 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 ch emicals, which contains 58 pesticide active ingredients and 9 inert ingredients. Dioctyl sodium

sulfosuccinate was not included on that list. For further information on the status of the EDSP, the policies and procedures, the list of 67 chemicals, future lists, the test guidelines and the Tier 1 screening battery, please visit our website: http://www.epa.gov/endo/

.

Timeline

The Agency has created the following estimated timeline for the completion of the diocty l sodium

sulfosuccinate registration review.

Registration Review for Dioctyl Sodium Sulfosuccinate

– Projected Registration Review

Timeline

Activities Estimated Date Opening the docket Open Docket and Public Comment Period 2010

– December

Close Public Comment 2011

– February Case Development

Final Work Plan 2011

– May Open Public Comment Period for Draft Risk Assessments 2012

– July

- Sept.

Close Public Comment Period 2012

– Oct.

– Dec. Registration Review Decision Open Public Comment Period f or Proposed Registration Review

D ecision 2013

– Jan.

- March

Close Public C omment P eriod 2013

- April

- June Registration Review D ecision and Begin P ost

- D ecision F ollow

- up 2013 Total ( years ) 3

Next Steps

The Agency plans to conduct a comprehe nsive ecological risk assessment, including an endangered species risk assessment, for the pesticidal uses of dioctyl sodium sulfosuccinate

. The draft of that

risk assessment will be available for public comment in 2012

.