Docket Number EPA

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Human Health & Environmental Effects Michelle Centra Nathan Mottl William Erickson Najm Shamim Siroos Mostaghimi

Health Effects Division Julie Van Alstine

Risk Management Sandra O’Neill Terria Northern Rose Kyprianou

Office of General Counsel Philip RossDocket Number EPA

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### Table of Contents
Introduction

................................ ................................ ................................ ........................... 4 1.1 Statutory and Regulatory Authority

................................ ................................ ............... 4 1.2 Case Overview

................................ ................................ ................................ ............... 5 1.3 Chemical Identification and Properties

................................ ................................ .......... 6 1.4 Use/Usage Information

................................ ................................ ................................ .. 7 1.4.1 Registrations

................................ ................................ ................................ .................... 7 1.5 Regula tory History

................................ ................................ ................................ ......... 7 1.5.1 Recent/Pending Regulatory Actions

................................ ................................ .............. 7 1.5.2 Tolerance Information

................................ ................................ ................................ .... 7 1.6 Incidents

................................ ................................ ................................ ......................... 7 1.6.1 Human Health Incidents

................................ ................................ ................................ . 7 1.6.2 Ecological Incidents

................................ ................................ ................................ ....... 8 Anticipated Data Needs

................................ ................................ ................................ ........ 8 Human Health Assessment

................................ ................................ ................................ ... 8 3.1 Hazard Characterization and Risk

................................ ................................ .................. 8 3.2 Dietary Exposure Assessment

................................ ................................ ........................ 8 3.3 Occupational and Residential Exposure Assessment

................................ ..................... 8 3.4 Aggregate and Cumulative Exposure

................................ ................................ ............. 9 Environmental Risk Assessment

................................ ................................ ........................... 9 4.1 Environmental Fate and Exposure

................................ ................................ ............... 10 4.2 Ecological Risk Characterization

................................ ................................ ................. 10 4.3 Threatened and Endangered Species

................................ ................................ ............ 10 Endocrine Disruptor Screening Program (EDSP)

................................ ............................... 10 Interim Registration Review Decision

................................ ................................ ................ 11 Next Steps

................................ ................................ ................................ ........................... 11

Appendix A T oxicology Profile

................................ ................................ ............................. 13 Appendix B REFERENCES

................................ ................................ ................................ .. 21

List of Tables Table 1

– Summary of Anticipated Risk Assessments and Data Needs for Registration Review for TBTO

................................ ................................ ................................ ................................ ........ 5 Table 2

– Anticipated Registration Review Schedule for TBTO

................................ .................... 5 Table 3

– Chemical Facts for TBTO

................................ ................................ ................................ 6Docket Number EPA

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## Introduction

This document is the Environmental Protection Agency’s (EPA or “ the a gency ” ) Interim Registration Review Decision for t ributyltin oxide , herein referred to as TBTO

, and is being issued pursuant to 40 CFR Sections 155.50, 155.5 6 and 155.58. This document explains what EPA’s Office of Pesticide Programs know s about TBTO

, noti ng that no additional data or further assessments are required, and provides an anticipated timeline for completing TBTO ’s review.

A registration review decision is the a gency's determination whether a pesticide meets, or does not meet, the standard for registration in the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). The agency may issue, when it determines it to be appropriate, a n interim registration

rev iew decision before completing a registration review. Among other things, the interim registration review decision may require new risk mitigation measures, impose interim risk mitigation measures, identify data or information required to complete the rev iew, and include schedules for submitting the required data, conducting the new risk assessment and completing the registration review.

The Proposed Interim Registration Review Decision for TBTO was issued for public comment on August 10 , 2015 and closed on October 9, 2015. During the 60

- day public comment period, no comments were received concerning the registration review of TBTO . As a result, no changes were made to the document.

TBTO, formerly known as the Tributyltin (TBT)

- Containing Compounds, is registered for use as an antifouling coating. It is formulated as ready

- to

- use solutions. The first tributyltin (TBT)

- containing product s w ere registered in the 1960’s

. The Reregistration Eligibilit y Decision document (RED) for TBTO was issued in 200 8. There are four registered TBT O p roducts use d in anti fouling systems in the U.S with two uses

. These two use s are for (1) incorporation into rubber for the formation of sonar domes used in US Navy vessels and for (2) use in antifoul ing devices within oceanographic instruments deployed by government researchers to monitor global ocean conditions (i.e., conductivity sensors). All other uses have been cancelled. Documents associated with this registra tion review can be found in docket EPA

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at www.regulations.gov

. 

## 1.1 Statutory and Regulatory Authority

The Food Quality Protection Act (FQPA) of 1996 mandated a registration review program. All pesticid es distributed or sold in the United States generally must be registered by the USEPA based on scientific data showing that they will not cause unreasonable risks to human health or the environment when used as directed on product labeling. The registratio n 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 of no unreasonable adverse effects to human health or the environm ent. Changes in science, public policy, and pesticide use practices will occur over time. Through the registration review program, the agency periodically reevaluates pesticides to make sure that as change occurs, products in the marketplace can be used sa fely. Information on this program is provided at http://www2.epa.gov/pesticide

- reevaluation.Docket Number EPA

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5 The agency is implementing the registration review program pursuant to Section 3(g) of the FIFRA and will review each registered pesticide every 15 years to determ ine whether it continues to meet the FIFRA standard for registration. The regulations governing registration review begin at 40 CFR 155.40. The agency will consider benefits information and data as required by FIFRA. The public phase of registration review begins when the initial docket is opened for each case. The docket is the agency’s opportunity to state what it knows about the pesticide and what additional risk analyses and data or information it believes are needed to make a registration review decisi on.



## 1.2 Case Overview

The docket for TBTO (case 2620 ) has been established at http://www.regulations.gov in docket number EPA

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- 080 1 . Documents associated with this registration review can be viewed in this docket. Tables 1 and 2 below summarize the issues relevant to this registration review case and the anticipated registration review schedule.

Table 1

– Summary of Anticipated Risk Assessments and Data Needs for Registration Review for TBTO

Risk Assessment Ass essment Necessary to

Support Registration Review Date of Most Recent Assessment Type of Assessment

Required (New/Updated) Data Anticipated as Needed

Dietary (food/ drinking water ) No N/A None None

Occupational & Residential Handler/Post Application No N/A None None

Aggregate No N/A None None

Cumulative No N/A None None

Tolerance Review No N/A None None Ecological No N/A None None N/A = Not applicable

Table 2

– Anticipated Registration Review Schedule for TBTO
Anticipated Activity Target Date Completion Date Combined Preliminary Work Plan and Interim Registration Review Decision and Implementation Open 60

- Day Public Comment Period for Combined Preliminary Work Plan and Proposed Interim Decision 06

- 201 5 08

- 10

- 2015

Close Public Comment Period 0 8

- 2015 10

- 09

- 2015
Issue Interim Decision 12

- 2015 Begin Post Decision Follow up * 201 6 Total (years) 1

* A final decision on the TBTO registration review case, in accordance with 40 CFR Section 155.58, will occur after an EDSP FFDCA section 408(p) determination has been made.Docket Number EPA

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## 1.3 Chemical Identification and Properties
Table 3 presents the active ingredient to be assessed in case 2620: TBTO (PC Code 083001). At the time of the 2008 RED , the case consisted of three compounds: bis

- tributyltin oxide (PC code 083001, TBTO), tributyltin benzoate (PC Code 083106, TBTB), and tributyltin maleate (PC Code 083118, TBTM). There are no inert uses of TBT in pesticides. The agency also notes that stannane, tributyl(2

- methyl

- 1

- oxo

- 2

- propenyl)o xy

- (PC Code 083120) is a TBT

- containing compound with no EPA registrations

, and therefore it will not be included in this registration review or undergo further evaluation

. As such, this registration review case will assess registrations only for TBTO (P C Code 083001).

Table 3

– Chemical Facts for TBTO

Chemical Name TBTO Pesticide type Antifouling Coatings (Nonfood Use) Case 2620 Chemical Classification Organometallic
PC Code 083001
CAS Number 26

- 35

- 9 Molecular Formula C 24 H 54 OSn 2 Molecular Weight (grams/mole) 596.12

Molecular Structure

Year first registered 1960 Reregistration Eligibility Decision (RED) 2008

Dual use Antimicrobial use only

40 CFR Citation There are no registered food/feed uses and no established tolerances for TBTO Antimicrobials Division, Chemical Review Manager Sandra O’Neill, oneill.sandra@epa.gov, (703) 347

- 0141
Antimicrobials Division, Product Manager Terria Northern

, northern. terria @epa. gov, PM reviewerDocket Number EPA

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## 1.4 Use/Usage Information

1.4.1 Registrations

There are four EPA

- registered products that contain TBTO as an active ingredient (a.i.) at concentrations of 2.7, 5.78

, and 53 percent a.i. TBTO . The end

- use product s are formulated as ready

- to

- use solutions.



## 1.5 Regulatory History

The first pesticides containing TBT compounds were registered in the 1960s, for use in antifouling paints. Adverse ecological effects associated with TBT antifouling paints captured global attention in the 1980s. In 2005, the agency processed the voluntary cancellat ion of the last TBT (now TBTO, PC code 083001) registration for ship hull antifouling use

. In 2008, EPA completed the Reregistration Eligibility Decision (RED) for TBT

- containing compounds

, and Data Call Ins ( DCIs ) requiring confirmatory data were issued in September 2011

. An international treaty prohibiting the use of TBT O hull coatings became effective in September 2008. It remains legal to distribute, sell , and use TBT O antifouling systems in the U.S. for two applications for (1) incorpora tion into rubber for the formation of sonar domes used in US Navy vessels and for (2) use in antifoul ing devices within oceanographic instruments deployed by government researchers to monitor global ocean conditions (i.e., conductivity sensors). The rubber application is considered to be critical for naval operations and releases a much smaller amount of TBTO into the aquatic environment than did the antifouling hull coatings. For the antifoul ing devices use, the total amount of TBTO present in the oceanogr aphic instruments is small, and the use is considered to be critical by government research organizations such as the National Oceanographic and Atmospheric Administration (NOAA)

. 

## 1.5. 1 Recent/ Pending Regulatory Actions

There are no recent or pending regulatory actions for TBTO.



## 1.5.2 Tolerance Information

There are no U

. S

. tolerances or exemptions from tolerances for TBTO because there are no currently registered uses under FIFRA for this active ingredient that are associated with food or feed.



## 1.6 Incid ents

1.6.1 Human Health Incidents
As of April, 2015, t here are no TBTO

- specific human incidents reported in OPP’s Incident Data System (IDS) that are associated with current registered uses of this antifouling agent when it is impregnated into rubber shee ts for the formation of sonar domes in U.S. Navy vessels and incorporated into instruments for monitoring global oceanographic conditions.Docket Number EPA

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## 1.6. 2 Ecological Incidents
There are no fish or wildlife poisoning incidents in OPP’s Incident Data System (IDS) involving TBTO as of March 2015. However, the agency is aware that numerous incidents occurred in aquatic ecosystems when the TBTs were widely used as antifoulant coatin gs on ship hulls (EPA 2008a,b).


## A nticipated D ata N eeds

Although there was a DCI for confirmatory studies from the RED, the uses triggering the need for confirmatory data were voluntarily cancelled

, and therefore, confirma tory data were not generated. Bas ed on the limited use pattern and low potential exposure, no new risk assessments are planned for TBTO and no additional data are anticipated to be required during registration review.


## Human Health Assessment

The agency’s human health risk assessment for TBTO which w as conducted for th e 200 8 RED can be found in the public docket EPA

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- 0171 at www.regulations.gov

. The agency does not anticipate updating the risk assessment for this re gistration review case.



## 3.1 Hazard Characterization and Risk
The toxicological database (Appendix A) i s considered adequate for character izing hazard and assessing risk fro m this use of TBTO (EPA 2008d) . No additional studies are anticipated to be needed for registrati on review.



## 3.2 Dietary Exposure Assessment

The four FIFRA

- registered uses of TBTO are not expected to result in direct or indirect dietary (food) or drinking water exposure. There are no FDA food use clearances for TBTO. Therefore, a dietary assessment is not required.



## 3.3 Occupational and Residential Exposure Assessment

There are four registered TBTO products (EPA Reg. N umbers 74487

- 1 , 1225

- 7, 1225

- 8, and 1225

- 11). These products are not labeled for residential uses and no residential exposure is expected

.

E PA Reg. No. 74487

- 1 is an anti

- fouling device impregnated with TBTO. T he antifouling device is used underwater within oceanographic instruments deployed by government researchers to monitor global ocean conditions. The amount of TBTO used in this antifouli ng device is minimal (< 0.1 ounces a.i. ) and t he label specifies that handlers must wear protective gloves when working with this device.

EPA Reg. Numbers 1225

- 7, 1225

- 8, and 1225

- 11 are for impregnated TBTO rubber sheet s that

are used on U.S. Navy ships and submarines for the sonar domes located on the hull . AccordingDocket Number EPA

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9 to the label s , the impregnated TBTO marine anti

- fouling rubber is designed with special acoustic properties to work well with sonar. Sonar domes are typically submerged under water on the hu ll of large ships and submarines. The product is a thin (<1/4 inch thick) TBTO impregnated neoprene rubber (NEOPRENE®) sheet that is used as an antifouling wrap for much of the exterior of the sonar dome. The rubber matrix minimizes the potential for hand ler and post application exposure to TBTO aerosols and the migration of TBTO residues for dermal contact during installation or cleaning when the ships or submarines are out of water. Additionally, dermal and inhalation handler exposures are also mitigated by the personal protective equipment (PPE) requirements on the product label which require that handlers use NIOSH/MSHA approved respirators, chemical resistant rubber gloves, safety glasses, face

- shields and disposable protective clothing.

O ccupational handler and post application exposure to TBTO while wearing the required PPE is minimal

. 

## 3.4 Aggregate and Cumulative Exposure

3.4.1 Aggregate Exposures

A ggregate exposure s are not anticipated since there are no dietary or residential concerns.

3.4.2 C umulative Exposures

With respect to cumulative exposure, unlike other pesticides for which EPA has followed a cumulative risk approach based on a common mechanism of toxicity, EPA has not made a common mechanism of toxicity finding as to TBTO and any othe r substances and TBTO does not appear to produce a toxic metabolite produced by other substances. For the purposes of this registration review, therefore, EPA has not assumed that TBTO has a common mechanism of toxicity with other substances. For informati on regarding EPA’s efforts to determine which chemicals have a common mechanism of toxicity and to evaluate the cumulative effects of such chemicals, see http://www2.epa.gov/pesticide

- science

- and

- assessing

- pesticide

- risks/cumulative

assessment

- risk

- pesticides

. 

## Environmental Risk Assessment

The agency has not previously conducted a risk assessment that supports a complete endangered
spec ies determination . No risk assessment has previously been conducted for the use of TBTO on naval sonar domes and oceanographic instruments deployed by government researchers. For the RED (EPA 2008a,b), the agency only assessed the potential environmental risks associated with use of the TBTO as an outdoor wood preservative, which was the major use of the TBTOs at that time. That assessment concluded that endangered aquatic invertebrates could be at acute risk from exposure to TBTO leached from wood and in to the aquatic environment.

The available acute toxicity data for a variety of freshwater and estuarine/marine species characterize TBTO as being very highly toxic to aquatic organisms (EPA 2008a,b). The open literature also contains considerable informa tion on the toxicity of TBTO to aquaticDocket Number EPA

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10 invertebrates, including reports of shell deformation in oysters and reproductive aberrations (imposex) in certain marine snails (EPA 200 3 ).



## 4.1 Environmental Fate and Exposure
TBTO is persistent in water (MRID # 41557801) and binds strongly to soils and sediments

. F ate data show that TBTO is highly bioaccumulative, and is not readily biodegradable. A fate assessment for TBTO was completed for the RED and can be found at www.regulations.gov in docket # EPA

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## 4.2 Ecological Risk Characterization
TBTO is highly toxic to aquatic organisms (EPA, 2008a,b)

. However, because TBTO is currently used only on sonar domes ( TBTO is incorporated into the rubber dome) and ma rine instrume nts, exposure would occur only fr o m the small amount of TBTO potentially leaching from the se surfaces. Additionally, because these applications use only a small quantity of TBTO, risks from leachate from the rubber domes and instruments are l ikely to be minimal

. Nevertheless, a potential for some risk exists if aquatic organisms are exposed to any TBTO that leaches out

. 

## 4.3 Threatened and Endangered Species
Although EPA has not previously conducted a risk assessment for TBTO to support a complete endangered species determination , the use of TBTO as an antifoulant on s onar d omes on vessels of the Armed Forces will be covered during the Department of Defense’s ( DoD's ) and EPA's Uniform National Discharge Standards (UNDS) consultation process . The UNDS rulemaking process was divided into two batches. Sonar Dome discharge is included in the "Batch 2" discharges. The Endangered Species Act ( ESA ) consultation for "Batch 2" is projected to begin in 2016.

Because potential risk to endangered spec ies will be evaluated by the UNDS consultation
process, EPA anticipates conducting no further analysis of potential risks to endangered or threatened species under registration review

. After the UNDS consultation is complete, any recommendations will be i mplemented on TBTO pesticide labels. 

## Endocrine Disruptor Screening Program (EDSP)

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 e ndocrine target organ histopathology, organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and chronic studies that ass ess growth, developmental and reproductive effects in different taxonomic groups. As part of its 200 8 RED for TBTO , EPA reviewed these data and selected the most sensitive endpoints for relevant risk assessment scenarios from the existing hazardDocket Number EPA

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11 database . However, as required by FFDCA section 408(p), TBTO 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 r equired determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a chemical substance to 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 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 id entify 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.

U nder FFDCA section 408(p), the a gency 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 nine inert ingredients. A second list of chemicals identified for EDSP screening was published on June 14, 201 3

1 2 and includes some pesticides scheduled for registration review and chemicals found in water

. Neither of these lists should be construed as a list of known or likely endocrine disruptors.

For further information on the status of the EDSP, the policies and procedures, the lists of chemicals, future lists, the test guidelines and the Tier 1 screening battery, please visit our website. 3

2 

## Interim Registration Review Decision

In accordance with 40 CFR Sections 155.50, 155.5 6 and 155.58, the a gency is issuing this Interim Registration Review Decision document. Except for the EDSP component of the TBTO registration review case, t he a gency has made the following proposed decision that n o additional data and no further risk assessments are require d

. In addition, EPA will rely on the ESA consultation for the DoD ’s and EPA’s UNDS to make a determination under the E SA for all listed species and designated cri tical habitat for such species. 

## Next Steps

A Federal Register N otice will announce the availability of this Interim R egistration R eview D ecision for TBTO

. The final decision on the r egistration r eview for TBTO will occur after the

2 See http://www.regulations.gov/#!documentDetail;D=EPA

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- OPPT

- 2009

- 0477

- 0074 for the final second list of chemical s. 3 http://www2.epa.gov/endocrine

- disruptionDocket Number EPA

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12 ESA consultation an d EDSP FFDCA section 408(p) determination have been made

. See the
est imated timeline for the completion of TBTO registration review in Table 2

.Docket Number EPA

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# Appendix A T oxicology Profile

Acute Toxicity for Product Labeling

TGAI tributyltin oxide has a high order of acute toxicity via the oral route of exposure (Toxicity Category II) ; it is not a skin sensitizer.

Table A1

– Acute Toxicity Studies for TGAI Tributyltin Oxide
Guideline No./ Study Type MRID Number(s) Results Toxicity Category

870.1100/ Acute oral toxicity 00085004, 92172013 LD 50 = 180 mg/kg (males) LD 50 = 150 mg/kg (females) LD 50 = 170 mg/kg (combined) I I

870.1100/ Acute oral toxicity 00085003, 92172004 LD 50 = 123 mg/kg (females) LD 50 = 160 mg/kg (combined) II

870.2600/ Skin sensitization 00104789, 92172014 Buehler: Not a skin sensitizer Not applicable 

## Subchronic/Chronic Toxicity Studies

Table A2

- Subchronic, Chronic and Other Toxicity Profile for TGAI Tributyltin Oxide

Guideline No. and Study Type MRID No. and Citation Dosing and Animal Information Results

Range

- finding Toxicity
Non

- guideline Range

- finding Study in Mice MRID 41127001 Daly, I. (1989) A three month oral range

- finding toxicity study in mice with bis (tri

- n

- butyltin ) oxide (TBTO). Bio/dynamics, Inc. (East Millstone, New Jersey). Unpublished. CD

- 1 ® mice (male and female)

Purity 97.1 % a.i.

0 , 4, 20, 80, or 200 ppm (equivalent to 0.7, 3.8, 15.1, or 36.9 mg/kg bw/day in males; 1.0, 4.9, 17.9, or 46.9 mg/kg bw/day in females) for 13 weeks (diet). NOAEL = 4 ppm (equivalent to 0.7 mg/kg bw/day in males; 1.0 mg/kg bw/day in females). LOAEL = 20 ppm (equivalent to 3.8 mg/kg bw/day in males; 4.9 mg/kg bw /day in females) based on mild hepatotoxicity and dermal irritation in the ear observed in male mice. Un acceptable /Non

- g uideline

Non

- guideline Range

- finding S tudy in Dogs MRID 41131001 Schweinfurth, H. (1987) Tributyltin oxide: Systemic toxicity study in Beagle dogs with daily oral (intragastric) administration over a total of 18

- 19 weeks. Schering AG, Berlin, Germany. Laboratory Project ID: TX 87.054, August 5, 1987. Unpublished. Beagle dogs

Purity >96.1% a.i.

0, 0.1, 0.5, or 2.5 mg/kg during Weeks 1

- 5; 0, 0.2, 1.0, or 5.0 mg/kg during Weeks 6

- 10; and 0, 10, 1.0, or 5.0 mg/kg during Weeks 11

- 19. Exposure to Tributyltin oxide caused elevated alkaline phosphatase and slight changes in serum protein composition at 1.0 mg/kg/day after 13

- 14 weeks of exposure. While further biochemical changes and suspected effects on red and white blood cells were observed at 2.5 mg/kg/day after 5 weeks of exposure and at 5.0 mg/kg/day after 13

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weeks of exposure, there was no evidence of organ toxicity. At 10 mg/kg/day, general toxic effects leading to weight loss and lymphotoxic effects, vacuolization of the liver cells and inhibition of follicle maturation in the ovaries (secondary effect) were observed. A dose of 10 mg/kg/day was considered to be too toxic of a dose for the 1

- year oral dog study; therefore, dose levels of 0.2, 1.0, and 5.0 mg/kg/day were recommended for the 1

- year study. Unacceptable/ Non

- guideline Prenatal Developmental Toxicity
870.3700 Prenatal Developmental Toxicity Study MRID 00137158 Schroeder, R.; Hogan, G. (1981) A Teratology Study in Rats with Tributyltin Oxide: Project No. 80

- 2497A. Final rept. (Unpublished study received Jan 16, 1984 under 5204

- 1; prepared by Bio/dynamics, Inc., submitted by M & T Chemicals Inc., Rahway, NJ; CDL:252178

- A).

MRID 92172016 Schroeder, R. (1992) M&T Chemicals, Inc. Phase 3 Reformat of MRID 00137158. A Teratology Study in Rats with Tributyltin Oxide: Project No. 80

- 2497A. Prepared by Bio/dynamics, Inc. 83 p. Female pregnant CD ® (Sprague

- Dawley derived) rats

Purity not reported

0, 5, 9, 18 mg/kg/day (via gastric intubation (gavage) Maternal Toxicity NOAEL = 5 mg/kg/day LOAEL = could not be identified due to the lack of data.

Developmental Toxicity NOAEL is less than 5 mg/kg/day LOAEL is equal to or less than 5 mg/kg/day based on increased incidences of ossification variations. A cceptable / Guideline

870.3700 Prenatal Developmental Toxicity Study MRID 40141901 Nemec, M. (1987) (Tributyltin Oxide)

- A Teratology Study in Rabbits with TBTO: Laboratory Project ID: WIL

- B0002. Unpublished study prepared by Wil Research Laboratories, Inc. 210 p. New Zealand White female rabbits

Purity >95%

0, 0.2, 1.0, 2.5 mg/kg/day ( oral gavage) Maternal Toxicity NOAEL = 1.0 mg/kg/day LOAEL = 2.5 mg/kg/day, based on increased incidence of abortion and decreased mean maternal body weight gain.

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MRID 92172006 Stevens, A. (1990) M&T Chemicals, Inc. Phase 3 Summary of MRID 40141901. A Teratology Study in Rabbits with TBTO: Project No. WIL

B0002. Prepared by Wil Research Laboratories, Inc. 7 p. LOAEL = is greater than 2.5 mg/kg/day (could not be established) Acceptable/ Guid eline

Reproduction and F ertility R ates 870.3800 Reproduction and

Fertility effects MRID 41693801 Schroeder, R.E. (1990) A two generation reproductions study in rats with bis (tri

- n

butyltin) oxide

. Bio/dynamics, Inc., East Millstone, NJ. Laboratory Project No.: 88

- 3261, October 22, 1990. Unpublished Sprague Dawley rats

Purity 97.1%

0, 0.5, 5, or 50 ppm for two successive generations (diet) Parental Toxicity NOAEL = 5 ppm (equivalent to 0.33/0.39 mg/kg/day in males/females). LOAEL = 50 ppm (equivalent to mg/kg/day 3.47/3.93 in males/females) based on anogenital staining in the P dams; decreased body weights in the F1 males and females during pre

- mating and continuing in the F1 males during the mating and post mating periods; and decreased ab solute and relative thymus weights in the F1 males.

Reproductive Toxicity NOAEL = 50 ppm (equivalent to 3.47/3.93 mg/kg/day in males/females) LOAEL = greater than 50 ppm (not established)

Offspring Toxicity NOAEL = 5 ppm (equivalent to 0.33/0.39 mg/kg/day in males/females). LOAEL = 50 ppm (equivalent to 3.47/3.93 mg/kg/day in males/females) based on decreased pup body weights in both generations Acceptable/ Guideline Chronic Toxicity
870.4100 Chronic Toxicity MRID 42549801 Schuh, W. (1992) Bis (tri

n

- butyltin) oxide (TBTO; ZK 21.955): 12

- month chronic oral toxicity study in beagle dogs. Schering AG, Berlin, Germany. Laboratory Project ID: Beagle dogs

Purity 95.9

- 97.1% a.i

.
0, 0.2 , 1.0 , or 5.0 mg/kg/day for 52 weeks (oral gavage) Multiple microscopic finding indicative of immunotoxicity (detailed above) were noted at 1.0 mg/kg/day, particularly in the males. At 5.0 mg/kg/day, increased severity of immunotoxicity and indications of systemic toxicity (including mortality, clinical signs of toxicity,Docket Number EPA

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Study Number TX 85.330, September 4, 1992. Unpublished. overall body weight losses, decreased body weights and food and water consumption, increased blood sedimentation rate, decreased nucleated bone marrow cellularity, increased hepatic enzym es, increased liver weight, decreased spleen and thymus weights, and gross pathological findings in the liver, spleen, and thymus) were observed. Unacceptable/ Guideline (not upgradeable) Carcinogenicity
870.4200 Carcinogenicity MRID 42265001 Daly, I. (1992) An eighteen month oncogenicity feeding study in mice with bis (tri

- n

- butyltin) oxide (TBTO). Bio/dynamic, Inc. Project No. 87

- 3131, March 27, 1992. Unpublished CD

- 1 mice

Purity 97.1% pure

0, 5, 25, or 50 ppm (equivalent to 0.7, 3.7, and 7.7 mg /kg/day for low

- , mid

- , and high

- dose males, respectively, and 0.9, 4.8, and 9.2 mg/kg/day for low

- , mid

- , and high

- dose females, respectively) for 18 months (diet) LOAEL = 0.7 mg/kg/day ( males ) LOAEL = 0.9 mg/kg/day ( females ), based on decreased survivor ship and increased body weight gain

. Acceptable/ Guideline

Combined Chronic Toxicity/Carcinogenicity
870.4300 Combined chronic toxicity/Carcinoge nicity MRID 40623201 Wester, P.W.; Krajnc, E.I.; et al. (1988) Bis (tributyltin) oxide

– Two year feeding study in rats with bis (tri

- n

- butyltin) oxide. RIVM, Bilthoven, The Netherlands. Laboratory Report No.: 658112 002, February 25, 1988. Unpublished. Wistar rats

Purity 95.3% a.i.

0, 0.5, 5, or 50 ppm (approximat ely equivalent to 0, 0.025, 0.25, and 2.5 mg/kg bw/day (diet) NOAEL = 5 ppm (approximately equivalent to 0. 25 mg/kg bw/day)

. LOAEL = 50 ppm (approximately equivalent to 2.5 mg/kg bw/day) based on increased mortality, systemic toxicity (ataxia, emaciation and decreased body weight/body weight gain in males and females) and organ toxicity (kidney, thyroid, adrenal glands, and pituitary. Acceptable/ Guideline
Mutagenicity
870.5100 Bacterial R everse

M utation T est MRID 42170001 Lang, R. (1986) Evaluation in the Ames Salmonella/Microsome Mutagenicity Test: ZK 21.955: Lab project Number: TX6106. Unpublished study prepared by Schering Ag. 29 p. Salmonella typhimurium TA 1535, TA 1 00, TA1537, TA 1538, and TA 98

Purity: 97.1 ± 3.4 % and 103 ± 5.6%

0.0001, 0.00025, 0.0005, 0.001, 0.0025, 0.005, 0.01, 0.02 and 0.03 μl/plate (without metabolic activation) Negative

No evidence of mutagenic activity in the presence or absence of metabolic activation (S9 from rat liver) in strains of S. typhimurium. Acceptable/ GuidelineDocket Number EPA

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0, 0.001, 0.0025, 0.005, 0.01, 0.02, 0.03, 0.04 and 0.05, 0.08 or 0.15 μl/plat e (with metabolic activation) 870.5375 In vitro C hromosome A berration T est (Rat) MRID 40253005 Brunneman, A. (1986) Evaluation of the Clastogenic Potential in the Human Lymphocyte Test: ZK 21.955: Lab. Proj. ID IC 4/86. Un

published study prepared by Schering AG. 23 p. human lymphocyte

Purity 97.1 ± 3.4% and 103.0 ± 5.6% 0.0025, 0.005, 0.01, 0.025, 0.05, 0.1, 0.25, 0.5 and 1.0 μg/ml (without activation)

0.01, 0.025, 0.05, 0.1, 0.25, 0.5, 1.0, 2.5 and 5.0 μg/ml with metabolic activation Negative

There was no evidence of chromosome aberration induced when compared with the negative
cont rol. However, at higher concentrations reduction in the mitotic index was observed. Acceptable/Guideline

870.5385 or 870.5395 Study not submitted

Metabolism and Pharmacokinetics
870.7485 Metabolism and Pharmacokinetics MRID 01246480 Evans, W., D. Smith, and N. Cardarelli (date of study not provided) Accumulation and excretion of [1

- 14 C] bis (tri

- n

- butyltin) oxide in mice. Environmental Management Laboratory, The University of Akron (Akron, Ohio). Unpublished. F emale COBS albino mice

Purity not reported

0, 0.51, 3.75, or 18.5 ppm Concentrations of 14 C

- TBTO were greatest in the kidneys, fat, liver, and spleen. Concentrations were found to be proportional to administered dose except in the kidney. Tissue accumulations were concentration dependent. The quantities absorbed were rapidly cleared when ingestion ceased. Acceptable/ Non

- guideline 870.7485 Metabolism and Pharmacokinetics MRID 40253002 Humpel, M. (1986) Toxicokinetics of 113 Sn

labelled tributyltin oxide after intravenous (1 mg/kg) and intragastric (25 mg/kg) administration to rats: bioavailability, excretion, and biotransformation. Schering AG, Berlin, Germany. Laboratory report numbers IC

- Kl 3, KI 84 061, and KI 84 062. January 23, 1986. Unpublished

. F emale Wistar

- Han (SPF) rats

Purity (>99%a.i)

1 mg/kg or 25 mg/kg Absorption was very delayed after gavage administration, with a half

life of 9.5 hours. The intravenously administered 113 Sn

- labeled TBTO is rapidly di stributed, with only 3% of the dose remaining in plasma volume after 5 minutes post administration. Based on the high volume of distribution and the binding to the cellular constituents of the blood, authors conclude that TBTO has a pronounced aff inity for tissues. Acceptable / Non

- guideline

Dermal Penetration
870.7600

Dermal Penetration MRID 40050003 Hümel, M. (1985) Series 85

- 2: Percutaneous absorption of tributyltin Male baboon

Purity not reported The total recovery of radioactively labeled 113 Sn

- Tributyltin oxide was less than 50%, perhaps due to the incomplete removal of unabsorbedDocket Number EPA

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oxide (TBTO) through intact skin of baboon. Scherling AG, Berlin 65, Germany. Laboratory Project ID IC

- KI 2, June 12, 1985. Unpublished Dose volume 0.5 mL/25 cm 2 skin TBTO on the skin surface as a result of extensive spreading from the site of application. However, reviewer generated data indicates that the total
recovery was app roximately 75%. Unacceptable/ Non

- guideline Published Literature Non Guideline Literature Study Vos et al., (1990) Immunotoxicity of bis (tri

- n

- butyltin) oxide in the rat: Effects on thymus

- dependent immunity and on nonspecific resistance following long

- term exposure in young vs aged rats. Toxicol. Appl. Pharmacol. 105:144

- 155. Wistar Rats

Purity: 95.3% active ingredient

E xposure to TBTO for up to 18

mo nths

D ietary concentration s: 0.025, 0.25 and 2.5 mg/kg

- day. NOAEL = 0.025 mg/kg/day LOAEL = 0.25 mg/kg/day based on immunotoxicity (depression of IgE titers and increase in T. spiralis larvae in muscle) following 4 months and 16.5 months of exposure to Tributyl Tin Oxide. (Review by EPA/IRIS, 1997).

Under the Reregistration Eligibility Decision for the Tributyltin Compounds: Bis(tributyltin) oxide, Tributyltin benzoate, and Tributyltin maleate (Case 2620) (EPA 739

- R

- 08

- 005, June, 2008)

, toxicological endpoints were selected from the TBTO toxicity database for conducting risk assessments in occupational and non

- occupation settings (Table A3). These existing toxicological endpoints remain adequate for regulatory purposes and therefore, can be used to as sess potential TBTO risk(s) to humans during incorporation of this active ingredient into rubber for the formation of sonar domes used in U.S. Navy vessels and when used in antifoulant devices within oceanographic instruments deployed by government researc hers to monitor global ocean conditions (i.e., conductivity sensors). No additional toxicological data for TBTO are anticipated to be required. However, if new product registrations are submitted to the agency that are not support ed by these existing TBTO data, additional toxicological data may be required.

Table A3

- Summary of Toxicolog ical Endpoint Selection for TGAI Tributyltin Oxide

Exposure Scenario Dose Used in Risk Assessment (mg/kg/day) Special Sensitivity*, UF, Target M OE, for Risk Assessment Study and Toxicological Effects

Dietary Risk Assessments

Acute Dietary (females 13

- 49 and general population) No appropriate endpoints were identified in the oral toxicity studies that represent a single dose effect for the general population and females 13

- 49. In addition, the current use patterns for the tributyltin

- containing chemicals do not indicate the pote ntial for direct or indirect dietary exposures. Therefore, an acute dietary risk assessment is not required.Docket Number EPA

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Chronic Dietary (all populations) BMD 10 = 0.03 mg/kg/day based on immunosupression (established by EPA/IRIS and used to estimate the oral RfD). Special Sensitivity = 10 UF = 100 (10x inter

- species extrapolation, 10x intra

species variation)

Chronic RfD (cRfD) = 0.00003 mg/kg/day

Although the current use patterns for the tributyltin

containing chemicals do not indicate the potential for chron ic dietary exposures, this endpoint is selected for future reference. A chronic dietary risk assessment is not required. Open Literature Study

Vos et al. , (1990) Immunotoxicity of bis (tri

- n

- butyltin ) oxide in the rat: Effects on thymus

- dependent immunity and on nonspecific resistance following long

term exposure in young vs aged rats. Toxicol. Appl. Pharmacol. 105:144

- 155.

NOAEL = 0.025 mg/kg/day LOAEL = 0.25 mg/kg/day based on immunotoxicity (de pression of IgE titers and increase in T. spiralis larvae in muscle) following 4 months and 16.5 months of exposure to Tributyl Tin Oxide. (Review by EPA/IRIS, 1997).

Non

- Dietary Risk Assessments Incidental Oral Short

Term (1

- 30 days) and Intermediate

- Term (1

- 6 months) BMD 10 = 0.03 mg/kg/day based on immunosupression (established by EPA/IRIS and used to estimate the oral RfD). Special Sensitivity = 10 UF = 100 (10x inter

- species extrapolation, 10x intra

species variat ion) Target MOE res. = 1000 Open Literature Study

Vos et al. , (1990) Immunotoxicity of bis (tri

- n

- butyltin) oxide in the rat: Effects on thymus

- dependent immunity and on nonspecific resistance following long

term exposure in young vs aged rats. Toxicol. Appl. Pharmacol. 105:144

- 155.

NOAEL = 0.025 mg/kg/day LOAEL = 0.25 mg/kg/day based on immunotoxicity (depression of IgE titers and increase in T. spiralis larvae in muscle) following 4 months and 16.5 months of exposure to Tributyl Tin Oxide. (Review b y EPA/IRIS, 1997).

Dermal (all durations) BMD 10 = 0.03 mg/kg/day based on immunosupression (established by EPA/IRIS and used to estimate the oral RfD). Special Sensitivity = 10 UF = 100 (10x inter

- species extrapolation, 10x intra

species variation) Target MOE occ. = 100 Target MOE res. = 1000 Open Literature Study

Vos et al. , (1990) Immunotoxicity of bis (tri

- n

- butyltin) oxide in the rat: Effects on thymus

- dependent immunity and on nonspecific resistance following long

term exposure in young vs aged rats. Toxicol. Appl. Pharmacol. 105:144

- 155.

NOAEL = 0.025 mg/kg/day LOAEL = 0.25 mg/kg/day based on immunotoxicity (depression of IgE titers and increase in T. spiralis larvae in muscle) following 4 months and 16.5 months of exposure to Tributyl Tin Oxide. (Review by EPA/IRIS, 1997).Docket Number EPA

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Inhalation (all durations) BMD 10 = 0.03 mg/kg/day based on immunosupression (established by EPA/IRIS and used to estimate the oral RfD). Special Sensitivity = 10 UF = 100 (10x inter

- species extrapolation, 10x intra

species variation) Target MOE occ. = 100 Target MOE res. = 1000 Open Literature Study

Vos et al. , (1990) Immunotoxicity of bis (tri

- n

- butyltin) oxide in the rat: Effects on thymus

- dependent immunity and o n nonspecific resistance following long

term exposure in young vs aged rats. Toxicol. Appl. Pharmacol. 105:144

- 155.

NOAEL = 0.025 mg/kg/day LOAEL = 0.25 mg/kg/day based on immunotoxicity (depression of IgE titers and increase in T. spiralis larvae in

m uscle) following 4 months and 16.5 months of exposure to Tributyl Tin Oxide. (Review by EPA/IRIS, 1997).
Dermal Absorption Although there is no guideline dermal toxicity study (range

- finding study only) and no acceptable dermal absorption study (75% recovery of 113 Sn

- tributyltin oxide), a 15% dermal absorption factor for tributyltin oxide has been used (EPA/ 2005 ) for route

- to

- route extrapolation.
Carcinogenicity EPA has assigned tributyltin oxide to category D (U.S., 1987) or to the “cannot be determined” category for carcinogenicity (U.S. EPA, 1996) based on high spontaneous incidences of tumors in Wistar rats, incidence v ariability in the treated groups and absence of a dose

- effect relationship. UF = uncertainty factor, NOAEL = no observed adverse effect level, LOAEL = lowest observed adverse effect level, RfD = reference dose, MOE = margin of exposure, NA = Not Applicable

* The S pecial Sensitivity factor is applied to a selected dose if there is evidence of increased susceptibility to children from non

- dietary exposures to pesticides. Several published literat ure studies show that tributyltin oxide causes depression of immune functions dependent on the thymus, particularly in young animals. This is a critical effect that occurs at doses lower than those causing other toxicities. Th erefore, application of this factor provides adequate protection to the most sensitive population, children.Docket Number EPA

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21 

# Appendix B REFERENCES

MRID CITATION

00085003 Auletta, C.S., Hodge, P.S., Minczeski, N. et al. (1981)

. Acute Oral Toxicity Study in Rats: Project No. 6656

- 81. (Unpublished study received Oct 15, 1981 under 5204

- 1; prepared by Bio/ dynamics, Inc., submitted by M & T Chemicals, Inc., Rahway, N.J.; CDL:246070

- A).

00085004 Auletta, C.S., Hodge, P.S., Minczes ki, N. et al. (1981)

. Acute Oral Toxicity Study in Rats: Project No. 6657

- 81. (Unpublished study received Oct 15, 1981 under 5204

- 1; prepared by Bio/ dynamics, Inc., submitted by M & T Chemicals, Inc., Rahway, N.J.; CDL:246070

- B).

00104789 Bruan, W., Rin ehart, W. (1979)

. A Dermal Sensitization Study in Guinea Pigs: Compound TBTO: Project No. 5056

- 78. (Unpublished study received Mar 14, 1979 under 5204

- 1; prepared by Bio/dynam ics, Inc., submitted by M & T Chemicals, Inc., Rahway, NJ; CDL: 237804

- A).

01246480 Evans, W., D. Smith, and N. Cardarelli (date of study not provided) Accumulation and excretion of [1

- 14 C] bis(tri

- n

- butyltin) oxide in mice. Environmental Management Laboratory, The University of Akron (Akron, Ohio). Unpublished.

00137158 Schro eder, R., Hogan, G. (1981)

. A Teratology Study in Rats with Tributyltin Oxide: Project No. 80

- 2497A. Final rept. (Unpublished study received Jan 16, 1984 under 5204

- 1; prepared by Bio/dynamics, Inc., submitted by M & T Chemicals Inc., Rahway, NJ; CDL:25217 8

- A).

40050003 Hümel, M. (1985)

. Series 85

- 2: Percutaneous absorption of tributyltin oxide (TBTO) through intact skin of baboon. Scherling AG, Berlin 65, Germany. Laboratory Project ID IC

- KI 2, June 12, 1985. Unpublished.

40141901 Nemec, M. (1987)

. (Tr ibutyltin Oxide)

- A Teratology Study in Rabbits with TBTO: Laboratory Project ID: WIL

- B0002. Unpublished study prepared by Wil Research Laboratories, Inc. 210 p.

40253002 Humpel, M. (1986)

. Toxicokinetics of 113 Sn

- labelled tributyltin oxide after intrav enous (1 mg/kg) and intragastric (25 mg/kg) administration to rats: bioavailability, excretion, and biotransformation. Schering AG, Berlin, Germany. Laboratory report numbers IC

- Kl 3, KI 84 061, and KI 84 062. January 23, 1986. Unpublished.

40253005 Brunneman, A. (1986)

. Evaluation of the Clastogenic Potential in the Human Lymphocyte Test: ZK 21.955: Lab. Proj. ID IC 4/86. Un

- published study prepared by Schering AG. 23 p.Docket Number EPA

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22 40623201 Wester, P.W., Krajnc, E.I. et al. (1988)

. Bis(tributyltin) oxide

– Two year feeding study in rats with bis(tri

- n

- butyltin) oxide. RIVM, Bilthoven, The Netherlands. Laboratory Report No.: 658112 002, February 25, 1988. Unpublished.

41127001 Daly, I. (1989)

. A three month oral range

- finding toxicity study in mice with b is (tri

- n

- butyltin) oxide (TBTO). Bio/dynamics, Inc. (East Millstone, New Jersey). Unpublished.

41131001 Schweinfurth, H. (1987)

. Tributyltin oxide: Systemic toxicity study in Beagle dogs with daily oral (intragastric ) administration over a total of 18

- 19 weeks. Schering AG, Berlin, Germany. Laboratory Project ID: TX 87.054, August 5, 1987. Unpublished.

41557801 Pisigin, Rodolfo, PhD, Liu.Larry, PhD, Zavala, Pedro, PhD (1990). Hydrolysis of Bis (TBTO) in Water. S tudy Conducted at Laboratory of Environmental Science & Engineering, PO Box #1703, Gainsville, FL 32602

- 1703. Unpublished



### .

41693801 Schroeder, R.E. (1990)

. A two generation reproductions study in rats with bis (tri

n

- butyltin) oxide . Bio/dynamics, Inc., East Millstone, NJ. Laboratory Project No .: 88

- 3261, October 22, 1990. Unpublished.

42170001 Lang, R. (1986)

. Evaluation in the Ames Salmonella/Microsome Mutagenicity Test: ZK 21.955: Lab project Number: TX6106. Unpublished study prepared by Schering Ag. 29 p.

42265001 Daly, I. (1992)

. An eighteen month oncogenicity feeding study in mice with bis(tri

- n

- butyltin) oxide (TBTO). Bio/dynamic, Inc. Project No. 87

- 3131, March 27, 1992. Unpublished.

42549801 Schuh, W. (1992)

. Bis (tri

- n

- butyltin ) oxide (TBTO; ZK 21.955): 12

- month chronic oral toxicity study in beagle dogs. Schering AG, Berlin, Germany. Laboratory Project ID: Study Number TX 85.330, September 4, 1992. Unpublished.

92172004 Stevens, A. (1990) . M&T Chemicals, Inc. Phase 3 Summ ary of MRID 00085003. Acute Oral Toxicity Report: Grignard Sourced TBTO: Project No. 6656

- 81. Prepared by Bio/dynamics. 7 p. (Supplemental copy to MRID 00085003).

92172006 Stevens, A. (1990)

. M&T Chemicals, Inc. Phase 3 Summary of MRID 40141901. A Terato logy Study in Rabbits with TBTO: Project No. WIL

- B0002. Prepared by Wil Research Laboratories, Inc. 7 p.

92172013 Stevens, A. (1990) . M&T Chemicals, Inc. Phase 3 Summary of MRID 00085004. Acute Oral Toxicity Study: Alkyl Aluminum Sourced TBTO: Project No . 6657

- 81. Prepared by Bio/dynamics, Inc. 7 p. (Supplemental copy to MRID 00085004).Docket Number EPA

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23 92172014 Stevens, A. (1990) . M&T Chemicals, Inc. Phase 3 Summary of MRID 00104789. A Dermal Sensitization Study in Guinea Pigs: Compound TBTO: Project No. 5056

- 78. Prepared by Bio/dynamics. 6 p. (Supplemental copy to MRID 00104789).

92172016 Schroeder, R. (1992)

. M&T Chemicals, Inc. Ph ase 3 Reformat of MRID 00137158. A Teratology Study in Rats with Tributyltin Oxide: Project No. 80

- 2497A. Prepared by Bio/dynamics, Inc. 83 p.

PUBLISHED LITERATURE

Vos

, J

. S

. , De Klerk

, A

. , Kranjc

, E

. I . et al. (1990). Immunotoxicity of bis (tri

- n

- butyltin ) oxide in the rat. Effects on thymus dependent immunity and on nonspecific resistance following long

- term exposure in young versus aged rats. Toxicology and Applied Pharmacology, 105:144

- 155.

SUPPORTING AGENCY DOCUMENTATION

IRIS (1997) Toxicological Rev iew: Tributyltin oxide (CAS No. 56

- 35

- 9): In support of summary information on the Integrated Risk Information System (IRIS). U.S. Environmental Protection Agency, July 1997.


### Tributyltin Compounds

- Report of the Antimicrobials Division Toxicity Endpoint Selection Committee (ADTC) for Tributyltin Oxide, Tributyltin Maleate and Tributyltin Benzoate. PC Code (s) : PC Code (s) : 083001, 083106, 083118. CAS Registry Number(s): 56

- 35

- 9, 4342

- 36

- 3, 14275

- 57

- 1 (Memorandum: M. Centra to T. Lindheimer and J. Bloom , February 4, 2008).


### Tributyltin Compounds

– Toxicology Chapter in Support of Issuance of the Reregistration Eligibility Decision (RED) for Tributyltin Oxide, Tributyltin Maleate and Tributyltin Benzoate. PC Code(s): PC Code(s): 083001, 083106, 083118. CAS Registry Number(s): 56

- 35

- 9, 4342

- 36

- 3, 14275

- 57

- 1 (Memorandum: M. Centra to T. Lindheimer, J. Bloom and D. Isbell, February 4, 2008).

EPA

. 2008a. Reregistration Eligibility Decision for the Tributyltin Compounds: Bis(trib utyltin) oxide, Tributyltin benzoate, and Tributyltin maleate (Case 2620). EPA 739

- R

08

- 005, June, 2008.

EPA

. 2008b. Ecological Hazards and Risk Assessment for Tributlytin Compounds . Prepared by W. Erickson, Risk Assessment and Science Support Branch, Antimicrobials Division, January 18, 2008

.
EPA. 2003. Ambient Aquatic Life Water Quality Criteria for Tributyltin (TBT)

– Final

. Office of Water

, Office of Science and Technology, Health and E cological C riteria D ivision, Washington D.C. EPA 822

- R

- 03

- 03 1 . 138 pp.

EPA

. 1997. Reregistration Eligibility Decision (RED) for the Tributyltin Compounds

.