United States Chemical Safety June 2012 Environmental Protection and Pollution Prevention Agency (7510P)



# Sodium Pyrithione ( Sodium Omadine ) Registration Review : Final Work Plan June 2012Docket Number: EPA

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3 of 13 Sodium Pyrithione Registration Review Team

Human Health & Environmental Effects Timothy Dole Srinivas Gowda James Breithaupt David Bays

Risk Management Wanda Henson Lance Wormell

Office of General Counsel Philip Ross

________________________________________ S upporting documents for the Sodium Pyrithione Case may be found in the registration review docket EPA

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4 of 13 Introduction

This is the Final Work Plan (FWP) of the Environmental Protection Agency (EPA or “the Agency”) for the registration review of Sodium Pyrithione (Case 0209 )

. The work plan includes the expected registration review timeline . The work plan also a ddresses public comments received concerning the Preliminary Work Plan (PWP) in the Summary Document which was posted in the Sodium Pyrithione registration review docket , and any other comments concerning the initial docket postings. The Summary Document p rovided 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 determine whether it continues to meet the FIFRA standard for registration. Changes in science, public policy and pesticide use practices will 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 that statutory standard. Th e 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 Sodium Omadine Preliminary Work Plan (PWP) (PC Code 088004 ) was published on December 21, 2011 and the 6 0

- day comment period ended on February 21, 2011. This case was originally titled “Sodium Omadine” and has since been renamed “Sodium Pyrithione” to replace the trade name “Omadine” with the generic active ingredient name, “ pyrithione. ” The Preliminary Work Plan document is available on www.regulations.gov docket number EPA

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. The first product containing s odium p yrithione (PC Code 088004 ) as an active ingredient was registered in the United States in 1968

. Currently, there are 12 products containing s odium pyrithione as an active ingredient registered with EPA. They are used in metalworking cutting fluids, cooling and lubricating fluids, adhesives, caulks, patching compounds, sealants, pastes and grouts, paints (in

- can), inks, sponges, janitorial products (in

- container), hides/leather /leather products (surfaces), aqueous analytical and diagnostic reagents used in chemical and clinical

ana lysis, aqueous synthetic fiber lubricating (spin finishes), carrageenan based gels used in solid air fresheners, dry wall and gypsum, pearlite, plaster

- like, mineral used in manufacture of tile, chrome or vegetable tanned leather, for the dry film preserva tion of natural, and synthetic adhesives, latexes, urethane foams, caulks, patching compounds, sealants, architectural paints, industrial paints and coatings (including wood coatings), glues, in

- can preservation of latex emulsions used in adhesives, laundr y rinse additives, laundry detergents, carpet cleaners, surface cleaners, floor cleaners, pigment slurries, building materials such as joint cements and concrete additives, materials in the textile, paper, polishes waxes, protein solutions, ceramic glazes, fire extinguishing materials, cleaning solutions and detergents as a materials preservative. There are no tolerances or exemptions from tolerances established by the EPA for sodium pyrithione

. Sodium pyrithione is approved by FDA as a preservative of adh esives in food contact packaging (21 CFR 175.105).Docket Number: EPA

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5 of 13 The Agency completed a Reregistration Eligibility Decision (RED) for Sodium Omadine in 1996

. Comments Received on the Preliminary Work Plan

The Agency received two comments during the public comment peri od on the initial docket, described below. In the PWP, the Agency solicited comments on specifi c topics: environmental justice, water body impairment

, trade irritants , and structure activity relationships

. No comment s or information were received during the public comment period concerning these issues

.
COMMENT #1 : The registration review case name should be changed to the common chemical name

- Sodium Pyrithione. OMADINE is a trade name of one of the registrants. In addition, all future registrati on review documents should reflect the common name rather than by tradenames, except when it is appropriate as in product brand names.

RESPONSE #1 : Case 0209 has bee n renamed to "Sodium Pyrithione " and future documents associated with this registration re view will refer to the generic active ingredient name, sodium pyrithione.

COMMENT # 2 : The footnotes related to the environmental fate testing schemes are confusing and could be further clarified. Some specific points are below. i. The footnotes speaks of a Modified ASRI study but the footnote mentions just ASRI (not modified). Are they the same test and GLN? ii. GLN 835.3280

– Simulation Tests to the Biodegradability of Chemicals Discharged to Wastewater is one of the EFATE studies in the list of studies, but is not mentioned at all in the footnotes, so it unclear when required and how this fits in. iii. The footnote mentions a Biodegradation in Activated Sludge study, but this study is not one of those mentioned in the EFATE list of studies needed, and the re is no Guideline number associated with that study. iv. One of the criteria for the second level of testing is whether the EC50 test result from the ASRI study is < or > 20 mg/L, but except for Ready Biodegradability study for > 20 mg/L the tests are all the same. v. It is mentioned that if a Ready Biodegradability study is conducted and the product passes then no further testing is required. For antimicrobial chemicals which have activity vs microbes it makes more sense to test directly in one of the oth er 3 EFATE test options. Is the ready biodegradability a required study or just one of the 4 options if test results for ASRI giving EC50 > 20 mg/L.

RESPONSE #2 : i). EPA has updated the anticipated data requirements to correctly reflect the need for the ASRI study rather than the t he Modified ASRI study.” ASRI (OECD 209) and Modified ASRI for Sparingly Soluble Chemicals (OCSPP 850.6800) are similar tests. OCSPP 850.6800 is a modification of OECD 209 that can be used for test substances that are not solu ble enough to make concentrated stock solutions in water. In that case, the test substance can be added directly to individual test vessels or alternatively, as a concentrated stock solution in an organic solvent.

ii) Guideline 835.3280 has five parts. Only one part is required: “314B: Biodegradation in Activated Sludge”. In referring to “(ii) Biodegradation in Activated Sludge” in the footnote, the Agency is referring to the part of 835.3280 that is required (i.e., 314B:Docket Number: EPA

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6 of 13 Biodegradation in Activated Sl udge). Guideline numbers associated with choices in the footnote are as follows:

a. T he result of the ASRI EC50 is less than or equal to 20 mg/L, then one of three biodegradation simulation tests (835.3220, 835.3280, or 835.3240) will be required.

b. T he result of the ASRI EC50 is above 20 mg/L, then either a Ready Biodegradability test (835.3110) or one of the above three biodegradation simulation tests (835.3220, 835.3280, or 835.3240) will be required. If the Ready Biodegradability test (835.31 10) is run and the result is negative, then one of the three biodegradation simulation tests (835.3220, 835.3280, or 835.3240) is also required.

iii) See response to ii above.

iv) The commenter is correct that, with the exception of the Ready biodegradab ility test, the choice of biodegradation studies is the same whether the results for the ASRI test is less than or equal to 20 mg/L or is greater than 20 mg/L. The same biodegradation information is needed for both cases. However, to provide flexibility for those test substances known to be relatively nontoxic to activated sludge microbes and suspected to be readily biodegradable an option to by

- pass the biodegradation simulation testing is provided in the form of the Ready Biodegradability test. If tox icity of the test substance to activated sludge microbes is such that the EC50 is >20 mg/L, there is an option to first conduct a Ready Biodegradability test rather than one of the three biodegradation simulation tests. If the Ready Biodegradability test passes, there is no need to conduct a biodegradation simulation test. Only if the test substance fails the Ready Biodegradability test is a biodegradation simulation test required. Alternatively, under this option the registrant can choose to by

- pass the Ready Biodegradability option and conduct one of the three full biodegradation simulation tests.

v) See response to iii above.

COMMENT # 3 : The formulation types are not consistently categorized amongst all the products. 43813

- 48 and 87772

- 2 are also read y

- to

- use solutions like 1258

- 843. Products 43813

- 49 and 87772

- 1 are manufacturing concentrates, not a technical chemical or formulation intermediate, respectively.

RESPONSE #3 : The information presented in Table 1, Registered Products

- Sodium Pyrithione, is based on information from EPA files. If you believe EPA's information is incorrect or outdated, please submit a written request for updates to the EPA Product Manager or C hemical Review Manager along with any supporting documentation needed to verify the request.

COMMENT # 4 : The TGAI is listed as the test material on page 18, Table 2. The product chemistry section mentions testing on a 97% technical material, however there is no registered technical grade product (see comment 3 above) as most/all products areDocket Number: EPA

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7 of 13 likely formulated by an integrated process. The most appropriate test material is the 40

- 42% products.

RESPONSE #4 : In the case of sodium pyrithione, the Agency would prefer testing be conducted with the highest purity technical grade material. This obviates the need for duplicate data development for each technical grade active ingredient product unless there are unique TGAI impurities that also need to be considered in the effects testing.

COMMENT #5 : The Agency is aware of the existence of the Antimicrobial Exposure Assessment Task Force II (AEATF II) and the conduct of a liquid pour study by the AEATF II and planning of the paint and metal working fluid (MWF) expos ure studies. Does the Agency plan to accept the liquid pour study for the treated materials mentioned (paints, MWF, household cleaners)? AEATF has not envisioned incorporating a separate “pour” study into either the MWF or paint studies

RESPONSE #5 : T he s tudy was designed for liquid pour scenarios and EPAanticipates that the results of the study will satisfy the da t a requirement. O nce the AEATF study is submitted it will be reviewed by the EPA and H uman S tudies R eview B oard (HSRB) to determine whether or n ot the study is acceptable for use in EPA risk assessment.

COMMENT #6 : For surface residue dissipation and leaching studies, does the Agency view one of the scenarios for each as worst case (dissipation from dishes, floors, carpets, or leaching from leather or textiles) to run a single study?

RESPONSE #6 : Residue data ar e needed for dishes, floors, carpets, and textiles. If the registrant believes the results of a single study can represent all of these uses, a written justification must be submitted to the Agency for review prior to initating the study. The justificatio n should include an explanation of why one study could represent the uses intended to be assessed and details of the proposed study (e.g., which use has the high concentration, which application technique (e.g., surface application versus impregnated) will result in the most residue transfer, which surface will transfer the most residue).

COMMENT #7 : October 12, 2011 Memorandum

– The executive summary mentions the need for textile and leather leaching studies but table 5, page 13 mentions surface residue dissipation studies for textiles and leaching. This should be clarified as these are different study types.

RESPONSE #7 : The leaching studies in the executive summary and the surface residue dissipation studies in the body of the document refer to the sa me studies.

COMMENT # 8 : If p hotodegradation data show that s odium p yrithione dissociates at low levels, existing environmental fate data using other Omadine salts should be bridgeable to fulfill the environmental fate data requirements for 850.6800, 835 .3220, 835.3280, 835.3240, 835.3110.

RESPONSE #8 : Photodegradation testing results have no bearing on the Agency’s decision to require wastewater treatment plant tests (i.e., Activated Sludge Respiration Inhibition (ASRI; 850.6800 or OECD 209); Activated Sludge Sorption Isotherm (ASSI;Docket Number: EPA

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8 of 13 835.1110); and wastewater treatment plant biodegradation (835.3110 or 835.3220 or 835.3280 or 835.3240)) nor do they inform the Agency’s decision on whether or not to bridge data from one pyrithione and/or its degradates to another pyrithione and/or its degradates.

The comments 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 d ocument makes final the work plan for the Sodium Pyrithione registration review process.

Risk Assessments and Anticipated Data Needs

The Agency will conduct a comprehensive ecological risk assessment, including an endangered species risk assessment, for all uses of s odium p yrithione. The Agency will conduct a human health risk assessment for sodium pyrithione

. The Agency expects to require additional d ata for use in conducting the registration review for s odium p yrithione.

Ecological Risk Assessment Status and Anticipated Data Needs

No recent ecological risk assessment has been performed for Sodium Pyrithione

. The Agency anticipates the need to require the following additional ecological data for use in conducting the registration review of Sodium Pyrithione.

850.5400

-- Algal Toxicity ( Tier II ) using freshwater green alga, Selenastrum capricornutum.

The Agency anticipates the need to require th e following additional environmental fate data for use in conducting the registration review of Sodium Pyrithione.

835.2240

-- Photodegradation in water 850.6800

-- A ctivated sludge, respiration inhibition test 835.3110

-- Ready Biodegradability 1
835.3220

– Porous Pot Test 1
835.3280

-- Simulation Tests to Assess the Biodegradability of Chemicals Discharged to Wastewater 1
835.3240

– Simulation Tests

– Aerobic Sewage Treatment: A. Activated Sludge Units 1

1 The results of the Activated Sludge Respiration Inhibition Test (ASRI) will determine which of these four biod egradation tests will be required. If the ASRI test EC50 is less than or equal to 20 mg/L, then either the (i) Biodegradation in Activated Sludge Study or (ii) Simulation Test

– Aerobic Sewage Treatment: A. Activated Sludge Units or (iii) the Porous Pot T est would be required. If the ASRI test EC50 is greater than 20 mg/L, then the registrant can choose to conduct either: (i) Ready Biodegradability or (ii) a) Biodegradation in Activated Sludge or b) Simulation Test

– Aerobic Sewage Treatment: A. Activated Sludge Units or c) the Porous Pot Test. If the Ready Biodegradability study is conducted and passes, then no further testing is required. If, however, the antimicrobial fails the Ready Biodegradability study, then the a) Biodegradation in Activated Slud ge or b) Simulation Test

– Aerobic Sewage Treatment: A. Activated Sludge Units, or c) the Porous Pot study is required.Docket Number: EPA

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9 of 13 F or more information

, please refer to Product Chemistry, Environmental Fate, and Ecological Effects Scoping Document in Support of Registration Review of Sodium Pyrithione , located in the docket

.
Human Health Risk Assessment Status and Anticipated Data Needs

No recent human health risk assessment has been performed for s odium p yrithione

. Dietary Assessment

Most of the labels have the statement “Do not use for applications involving direct or indirect food/drinking water contact.” Three labels (#1258

- 990, #1258

- 1205 and #39967

- 26) do not have this statement; however, and label #39967

- 26 is approved for uses such as paper, cleaning solutions and detergents that might involve food contact. Sodium Pyrithione is also approved by FDA as a preservative of adhesives in food contact packa ging (21 CFR 175.105). Given these approvals, it will be necessary to assess indirect food contact exposures from these uses and residue data will be needed.

The registered uses of Sodium Pyrithione might result in contamination of surface and ground wate r as a result of discharges of treated water from industries using this antimicrobial as a material preservative. Therefore, drinking water exposure might occur. However, the need for a drinking water exposure assessment will be determined upon review of the environmental fate data that the Agency anticipates requiring. These data will be used to determine if Sodium Pyrithione can pass through wastewater treatment plants into drinking water. Therefore, the need for a drinking water assessment will be rev isited upon submission and review of the environmental fate data.

Tolerances and International Harmonization

There are no tolerances or exemptions from tolerances established by the EPA for s odium
p yrithione. Sodium p yrithione is approved by FDA as a pres ervative of adhesives in food contact packaging (21 CFR 175.105).

Occupational and Residential Assessment and Risk

Occupational post application exposures that occur during the use of treated materials were not assessed for the RED because it was believed at the time that these exposures would be minimal because of low application rates and because Sodium Pyrithione has low vapor pressure. Although it is true that vapor exposures to Sodium Pyrithione will be minimal as stated in the RED, there is the pote ntial for dermal and inhalation exposures to aerosols during the use of materials such as paints, metal working fluids, surface cleaners and floor cleaners treated with Sodium Pyrithione. In addition, it will be necessary to reassess the general preservat ive uses because some materials have application rates of up to 5000 ppm which is much greater than the rate of 46 ppm that was assessed in the RED.Docket Number: EPA

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10 of 13 Sodium p yrithione residential exposure may occur during the use of treated products such as paints and coat ings, surface cleaners, floor cleaners, carpet cleaners, textiles and leather. Residential exposures were not assessed in the RED because it was believed at the time that the exposures would be very low due to dilution. While it is true that the use rate s are fairly low, the toxicological endpoints are also fairly low and therefore it will be necessary to assess these exposures during registration review.

Aggregate and Cumulative Exposure and Risk

In examining aggregate exposure, EPA takes into account the available and reliable information concerning exposures to pesticide residues in food and drinking water, as well as

non

- occupational pesticide exposures. An aggregate risk assessment in the case of sodium pyrithione will likely be needed because of t he use pattern w h ich is likely to result in dietary, drinking water and residential exposures.

EPA does not have, at this time, available data to determine whether s odium p yrithione has a common mechanism of toxicity with other substances or how to includ e this pesticide in a cumulative risk assessment.

For the purposes of this Registration Review, EPA has assumed that s odium p yrithione does not have a common mechanism of toxicity with other substances when used as an antimicrobial as registered.

Human He alth Anticipated Data Needs

The Agency anticipates the need to require the following additional human health data for use in conducting the registration review of s odium p yrithione

.

875.1100

-- Dermal outdoor exposure 875.1300

-- Inhalation outdoor exposure (HRSB costs not included) 875.1600

-- Application exposure data reporting and calculations 875.2300

-- Indoor surface residue dissipation 875.1700

-- Product use information

For more information, please refer to Sodium Omadine : Human Health Risk Assessment Scoping Document in Support of Registration Review

, located in the docket

. Product Chemistry Anticipated Data Needs

The Agency does not anticipate the need to require additional product chemistry data for the registration review at this time.

F o r more information

, please refer to Product Chemistry, Environmental Fate, and Ecological Effects Scoping Document in Support of Registration Review of Sodium Omadine

, located in the docket

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11 of 13 Incidents:

Ecological:

No Sodium Pyrithione ecological incidents have been reported in the Agency’s Ecological Incident Information System (EIIS).

Human Health:

No Sodium Pyrithione human poisoning incidents have been reported in the Agency’s OPP incident database.

Endangered Species

The Agency has not conducted a risk assessment that supports a complete endangered species determination for Sodium Pyrithione

. The ecological risk assessment planned during registration review will allow the Agency to determine whether Sodium Pyrithione ’s use has 'no effect' or 'may affect' federally listed threatened or endangered species (listed species) or their designated critical habitats. When an assessment concludes that a pesticide’s use 'may affect' a listed species or its designated critical habi tat, the Agency will consult with the U.S. Fish and Wildlife Service and/or National Marine Fisheries Services (the Services), as appropriate.

Endocrine Disruptor Screening Program

As required 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, developmental, 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, fertility, pregnancy rates, reproductive loss, and sex ratios in off

spring. 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), s odium p yrithione is subject to the endocrine screening 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 identify the potential of a chemical substance to interact with t he 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 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, o r T effect.Docket Number: EPA

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12 of 13 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 pesticide active ingredients and 9 i nert ingredients. Sodium Pyrithione is not among the group of 58 pesticide active ingredients on the initial list to be screened under the EDSP. Accordingly, as part of registration review, EPA will issue future EDSP orders/data call

ins, requiring the sub mission of EDSP screening assays for Sodium Pyrithione

. 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

EPA has created the following estimated timeline for the completion of the Sodium Pyrithione registration review:

Anticipated Schedule Activities Estimated Month/Year Phase 1: Opening the docket Open Public Comment Period for Docket Completed December 2011 Close Public Comment Period for Docket Completed

Phase 2: Case Development Develop Final Work Plan (FWP) Completed June 2012 Issue DCI June 2013 Data Submission June 2015 Open Public Comment Period for Preliminary Risk Assessments December 2016 Close Public Comment Period for Preliminary Risk Assessments January 2017 Phase 3: Registration Review Decision Open Public Comment Period for Proposed Reg. Review Decision June 2017 Close Public Comment Period for Proposed Reg. Review Decision August 2017 Final Decision and Begin Post

- Decision Follow

- up December 2017 Total (years) 6

Next Steps

A DCI will be developed regarding the data needs listed under the “Risk Assessments and Anticipated Data Needs” section of this document. The Agency expects to issue the DCI in June 2013 . Human health and environmental fate and ecological hazard assessment s will be conducted for all uses.Docket Number: EPA

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13 of 13 Summary of Anticipated Data Requirements

– Sodium Pyrithione

The table below summarizes anticipated data needs for the Sodium Pyrithione Case in this document (Final Work Plan), Product Chemistry, Environmental Fate, and Ecological Effects Scoping Document in Support of Registration Review of Sodium Pyrithione

, and Sodium Pyrithione : Human Health Risk Assessment Scoping Document in Support of Registration Review

. Table 1. Summary of Anticipated Data Requirements

– Sodium Pyrithione

Guideline Number Anticipated Data Requirement Test Material Estimated Timeframe

(Measured in months from DCI Receipt)

875.110 Indoor Exposure, Dermal TGAI 24

875.1300 Indoor Exposure, Inhalation TGAI 24

875.1600 Data Reporting/Calculations TGAI 24

875.2300 Surface Residue Dissipation TGAI 24

875.1700 Product Use Information TGAI 24

835.2240 Photodegradation in water TGAI 12

850.6800 Activated Sludge Respiration Inhibition TGAI 12

835.3110 Ready Biodegradability 2 TGAI 12

835.3220 Porous Pot Test 2 TGAI 12

835.3280 Simulation Tests to Assess the

Biodegradability of Chemicals Discharged to Wastewater 2 TGAI 12

835.3240 Simulation Test

– Aerobic Sewage Treatment:

A. Activated Sludge Units 2 TGAI 12

850.5400 Algal toxicity (Tier II) using freshwater green

alga, Selenastrum capricornutum TGAI 12

_______________________________

2 The results of the Activated Sludge Respiration Inhibition Test (ASRI) will determine which of these four biodegradation tests will be required. If the ASRI test EC50 is less than or equal to 20 mg/L, then either the (i ) Biodegradation in Activated Sludge Study or (ii) Simulation Test

– Aerobic Sewage Treatment: A. Activated Sludge Units or (iii) the Porous Pot Test would be required. If the ASRI test EC50 is greater than 20 mg/L, then the registrant can choose to condu ct either: (i) Ready Biodegradability or (ii) a) Biodegradation in Activated Sludge or b) Simulation Test

– Aerobic Sewage Treatment: A. Activated Sludge Units or c) the Porous Pot Test. If the Ready Biodegradability study is conducted and passes, then no further testing is required. If, however, the antimicrobial fails the Ready Biodegradability study, then the a) Biodegradation in Activated Sludge or b) Simulation Test

– Aerobic Sewage Treatment: A. Activated Sludge Units, or c) the Porous Pot study is required.