Russell Wasem Chemical Review Manager EPA Pesticide Re-Evaluation Division One PotomacYard 2777 S. Crystal Drive Arlington, VA 22202 TM/MBCTask Force c/o Nisso America Inc. 88 Pine Street, 14th Floor

New York, NY 10005

June 10, 2014

RE: Thiophanate-methyl and Carbendazim Registration Review (Case 2680) Commentsto Docket ID No. EPA-HQ-OPP-2014-0004

Dear Mr. Wasem:

The Thiophanate-Methyl and Carbendazim Task Force (TM/MBCTask Force) is hereby providing comments tothe public docket opened forthe Registration Review ofthiophanate-methyl and carbendazim. The TM/MBCTask Force is composed ofthe following registrant companies:

Adama USA, Gowan Company, Nippon Soda Co., Ltd

., Nufarm Americas, Inc., and Troy Corporation.

The TPM/MBCTask Force appreciates the opportunityto review and provide comments on EPA's preliminarywork plan and anticipated data requirements forthiophanate-methyl (TM) and carbendazim (MBC). These comments primarily focus on the Environmental Fate and Effects Division's (EFED) and the Health Effects Division's (HED) anticipated data requirements forTM and MBC, and are offered in the spirit ofmakingthe best use of both EPA's and the registrants resources forthe registration review ofTM and MBC.

The purpose ofthis letter is to provide additional informationtothe EPA with respect tothe anticipated data needs outlined in the PreliminaryWork Plan and its supportingdocuments from BEAD, EFED, and HED.

In EPA's preliminarywork plan and EFED's Preliminary Problem Formulation document, EFED has listed a number ofanticipated data requirements forTM and MBC. As ageneral comment, a numberofthe proposed environmental fate data requirements are for repeat studies forwhich acceptable studies have already been submitted (see Table 8 in the EFED Preliminary Problem Formulation document). Repeatingthese studies is unlikelyto result in any significant new data, or provide any substantial new information concerningthe environmental fate properties ofTM or MBC. Except for ageneral observation that a number ofthe environmental fate studies are old, for many ofthese repeat studies, EFED has not provided a rationale forwhy it believes new studies are necessary. The TM/MBCTask Force believes that in ordertofully appreciate the shortcomings ofthe existing data (and therebypreventthe same situation from occurring should a study be repeated), the Agency should release the Data Evaluation Records (DERs) forthe individual studies in question.
Regarding Anticipated Data Needs as Outlined in the Preliminary Work Plan forThiophanate-methyl
AnticipatedEnvironmental Fate Data Needsfor TM

EFED's proposed data requirements forTM include batch equilibrium testing, hydrolysis testing, aerobic soil metabolism, aerobic aquatic metabolism, anaerobic aquatic metabolism, and an environmental chemistry method and associated ILV forwater.

•Batch Equilibrium Adsorption/Desorption (835.1230) As mentioned in the EPA/EFED internal memorandum B. Montegue eta/to R. Wasem eta/ dated March 18, 2014 (DP Barcodes D413007 and D480778) on page 36, a previously submitted study (MRID 42351001; Shiotani, H. (1992) Thiophanate-methyl Batch Equilibrum (Adsorption/Desorption on Soild): Lab Project Number: NISSO EC-362. Unpublished study prepared by Nippon Soda Co., Ltd., Envir. Tox. Lab. 106 p.) may address this anticipated data need

. EPA indicated thatthis study is currently under review. The TM/MBCTask Force believes this study satisfies the batch equilibrium data requirement, and that no furthertesting is necessary.

• Hydrolysis (835.2120) In the EPA/EFED internal memorandum B. Montegue etalto R. Wasem etaldated March 18, 2014 (DP Barcodes D413007 and D480778), the Agency states on page 35 that "Existing [hydrolysis] studies will be re-reviewed." EPA indicated thatthis hydrolysis study is also currently under review. The TM/MBCTask Force believes thatthis study adequately satisfies the data requirement, and that no furthertesting is necessary.

•Aerobic Soil Metabolism (835.4100) The TM/MBCTask Force would like to point out an inconsistency associated withthis anticipated data need. The PreliminaryWork Plan identifiesthe anticipated data need for an aerobic soil metabolism study; however, in Table 8 on page 37 ofthe EPA/EFED internal memorandum B. Montegue etalto R. Wasem etaldated March 18, 2014 (DP Barcodes D413007 and D480778), the Agency states than an existing study (MRID 00106085) is "acceptable" and that "Due tothe rapid transformation [ofTM] to MBC (half-life< 1 day in all 3 soils) study may meet requirements for MBC as well." EFED proposed requesting additional studies on three soils with specific pH values (<6.0, <6.3, and>7.5). Acceptable aerobic soil metabolism data are already available forTM on three soils, and EFED has notexplained why it is requesting additional aerobic soil metabolism data as the results of these three studies are consistent.

While EFED has hypothesized thatTM is more stable in acidic soils, this does notexplain EFED's request fortesting in a soil with a pH <6.0, and in another soil with a pH <6.3; or EFED's request for testing in asoil with a pH >7.5, particularly forTM, forwhich all the available data indicate degrades very rapidly (DT50 <=1 day). This rationale concerning TM being more stable under acidic conditions than basic conditions is more applicable to abioticdegradation than microbially

-mediated degradation, and therefore it is notclear howthis hypothesis concerningthe effectofsoil pH is relevant tothe microbially-mediated degradationthat occurs in aerobic soil metabolism testing.•AerobicAquatic Metabolism (835.4200) Similarlywiththe aerobic soil metabolism, the Preliminary Work Plan mentions an anticipated data need forthis study but the March 18, 2014 EFED internal memorandum'sTable 8 on page 37 doesn't reflectthis as the existing study (MRID 45621401) is considered "supplemental" but no additional data were deemed necessary.

EPA is proposing aerobic aquatic metabolism testing in three systems; however, the guidelines only require aerobic aquatic metabolism testing in two systems. EFED has not provided a rationale as to why it is proposingto request aerobic aquatic metabolism testing in three separate systems.

EFED has not provided aclear rationale as towhy it is anticipatinga need for aerobic aquatic metabolism testing in three separate systems. EFED is suggesting testing with soils/sediments ofpHs <6.0, <6.3, and >7.5). EFED has not provided a rationale forthese selected pHs, particularlythe request fortesting soils/sedimentswith pHs ofsuch a narrow range (i.e., <6.0 and <6.3). These are the same pH values that EFED listed for its proposed aerobic soil metabolism testing, and it is notclear whether or howthis request concerning pH values is applicable tothe proposed request for aerobic aquatic metabolism testing. EFED's hypothesis thatTM is more stable underacidic conditionsthan basic conditions is more applicable to abiotic degradation than the microbially-mediated degradation that is the focus ofaerobic metabolism testing. Even ifthis hypothesis is accurate, itdoes notexplain EFED's request fortestingtwo acidic pH values.

An acceptable study (classified as "supplemental") fortwo systems (a river water system and a pond water system) is available forTM, so the anticipated need for additional testing is indistinct. The TM/MBCTask Force would benefit from receipt ofthe DER forthe existing studyto clarify why itwas classified as supplemental and why EFED believes thistesting on two aerobic aquatic systems needs to be repeated

.
•Anaerobic Aquatic Metabolism (835.4300) Table 8 on Page 37 ofthe EFED's March 18, 2014 internal memorandum states thatthe existing anaerobic aquatic metabolism study withTM (MRID 40061501) is "acceptable." This is inconsistent with the PreliminaryWork Plan's listofanticipated data needs. The data referenced in the Preliminary Problem Formulation document indicate thatTM degrades very rapidly (half-life of 1 day) under anaerobic aquatic conditions. Since an acceptable study is available, EPA-EFED's rationale for requiring additional anaerobic aquatic metabolism testing in three systems is unclear.

EPA is requesting anaerobic aquatic metabolism testing in three systems; however, the guidelines only require aerobic aquatic metabolismtesting in two systems. EFED has not provided a rationale as to why it is proposingto request anaerobic aquatic metabolism testing in three separate systems.

As with its request for aerobic soil metabolism testing and aerobic aquatic metabolism testing, EFED is requesting testingwith soils/sediments of pHs <6.0, <6.3, and >7.5). EFED has not provided a rationale forthese selected pHs, particularlythe request fortestingsoils/sediments with pHs of<6.0 and <6.3. These are the same pH values that EFED listed for its proposed aerobic soil metabolism testing, and it is notclearwhetheror howthis request concerning pH values is applicabletothe proposed request for anaerobic aquatic metabolism testing. EFED's hypothesis thatTM is more stable under acidic conditionsthan basic conditions is more applicable to abiotic degradation than the microbially-

### mediated degradationthat is the focus ofanaerobic metabolism testing. Even ifthis hypothesis is accurate, it does not explain EFED's request fortesting atwo acidic pH values.

•Environmental Chemistry Methods and Associated ILVs forWater (835.6200) An LC-MS/MS analytical method and validation report for quantitation of thiophanate-methyl (and carbendazim) in drinkingwater, ground 

### water, and surface water is available for submission to the Agency. The Limit ofQuantitation (LOQ) ofthe method for both analytes is 0.05

**~g/liter.** 

### The Task Force intends to submitthis methodtofulfill theAgency's request for an updated environmental chemistry method forTM in water.


### AnticipatedEcological Effects DataNeedsfor TM

EFED's proposed data requirements forTM include seedling emergence and vegetative vigor studies as well as honey·bee acute oral and larval toxicity studies.

•Terrestrial Plant Toxicity, Seedling Emergence (850.4100) Existing studies conducted at up to 1.41b ai/Aare acceptable and reflect the maximum use rate
on agricultural crops. Available data indicate no adverse effects on non-targetterrestrial plants atthe maximum agricultural use rate of 1.41b a.i./A. However, application rates on golfcourse tees and greens are higher (up to 8.161b a.i./A) while rates on fairways range up to 5.45lb a.i./A. Therefore the TM/MBCTask Force will considerthe conduct ofthe study relative to rate adjustments (ifany) on turf.

•Terrestrial Plant Toxicity, Vegetative Vigor (850.4150) Existing studies conducted at up to 1.4 lb ai/ A are acceptable and reflectthe maximum use rate
on agricultural crops. Available data indicate no adverse effects on non-targetterrestrial plants atthe maximum agricultural use rate of 1.41b a.i./A. 

### However, application rates on golfcourse tees and greens are higher (up to 8.16 lb a.i./A) while rates on fairways range up to 5.45 lb a.i./A. Thereforethe TM/MBCTask Force will considerthe conduct ofthe study relative to rate adjustments (ifany) on turf.
•Honey Bee Acute Oral Toxicity (OECD 213) A honeybee acute oral toxicity study (Nippon Soda Co., 

### Ltd.; RD-1131) conducted under GLP and the applicable OECD guidelines in 2005 is available and shows the 48 houracute oral LD50 value is> 114

**~g** 

### a.i./bee. These results indicate thatTM is practically non-toxicto honeybees on an acute oral basis. The contacttoxicityto honey bees was also determined in the study and was found to be > 100

**~g** 

### a.i./bee. The TM/MBCTask Force intends to submitthis studyto address the acute oral toxicitytesting with honeybees anticipated data need.
•Honey Bee Larval Toxicity (OECD 237) Both the acute contact and acute oral toxicityofTM are >100

**~g/bee** 

### therefore the TM/MBC Task Force questions the need for a honeybee larval toxicity study. EPA has not provided a rationale for needing data on larval toxicity given thatTM is practically non-toxicto honeybees on both an acute contact and acute oral basis. These two studies are sufficientto evaluate the toxicity ofTM to both adult and larval honeybees. Therefore, the TM/MBCTask Force requests thatthis anticipated data need be held in reserve until EPA has reviewed the acute oral toxicitystudy on honeybees.Anticipated Toxicology Data Needsfor TM

HED's proposed data requirements forTM include asubchronic inhalation study and adevelopmental thyroid study.

•Subchronic Inhalation Study Based on discussion with EPA during a meeting held on May 7, 2014, a28-day inhalation study is acceptable in lieu ofa90-day inhalation studytofulfill this data requirement. In the meetingthe Agency mentionedthe need to include evaluation ofthyroid effects and therefore theTM/MBCTask Force plans
on submitting a protocol for EPA review priorto initiating any study ofthistype

. •DevelopmentalThyroid Assay The TM/MBCTask Force recommends thatthe requirementfordevelopmental thyroid assay data be placed on reserve until the results ofthe on-going 2-Generation Modified Rat Reproduction Studywith Carbendazim are submitted and reviewed by the Agency. The on-going study includes an assessment ofthyroid parameters and is scheduled for submission in September 2014.

The followingthyroid related parameters were assessed in the ongoing F1-extended two generation reproductive toxicity study ofcarbendazim {MBC): thyroid hormone assessment for multiple life stages: Padults (male and female, T4 and TSH); F1 PND 4 pups (pooled samples, T4 and TSH); F1 PND 23 pups (male and female T4 and TSH); F1 adults (male and female T3, T4 and TSH, includingfrom females atthe end ofgestation (Cohort 1A) and T4 and TSH atthe end of lactation (Cohort 1B)); and F2 PND 23 pups (male and female T4 and TSH). Thyroid weights were taken for all groups except PND 4 pups. Thyroid histopathology, including subjective semi-quantitative scoring forfollicular cell height and colloid area was performed for Padults, F1 cohort 3 PND 23 weanlings, F1 Cohort 1B adult males and adultfemales, F2 PND 23 weanlings and asubset of F2 female weanlings held to PND 45. As some developmental neurotoxicity parameters may be affected by changes in thyroid hormone levels, it is also relevant that Cohort 2 {F1) ofthe MBC F1-extended two generation reproductive toxicity study evaluated potential developmental neurotoxicity, including Functional Observational Battery, motor activity, and auditory startle in adults; and neuropathology of perfused pups and adults (including stainingfor myelin deposition) and brain morphometry. Given the rapid breakdown ofthiophanate methyl to MBC, and the extensive thyroid and DNT data recently developed for MBC, we considerthe Agency should hold the data requirement for acomparative thyroid evaluation ofthiophanate methyl in reserve, pending review and evaluation ofthe MBC F1-extended two generation reproductive toxicity study.
Regarding Anticipated Data Needs as Outlined in the Preliminary Work Plan for Carbendazim (MBC)
AnticipatedEnvironmental Fate Data NeedsforMBC

EFED's proposed data requirements for MBC include batch equilibrium testing, hydrolysis testing, aerobic soil metabolism, aerobic aquatic metabolism, anaerobic aquatic metabolism, an environmental chemistry method and associated ILVfor soil and water, and leaching studies with various treated matrices.

•Batch Equilibrium Adsorption/Desorption {835.1230) As withthiophanate-methyl mentioned earlier, a previously submitted study (MRID 42351001; Shiotani, H. {1992) Thiophanate-methyi--Batch Equilibrum (Adsorption/Desorption on Soild): Lab ProjectNumber: NISSO EC-362. Unpublished study prepared by Nippon Soda Co., Ltd., Envir. Tax. Lab. 106 p.) may address this anticipated data need. Table 8, page 38 in EFEO's March 18, 2014 internal memorandum also states that MRIO 42351001 is "acceptable" and no further data are needed. The TM/MBCTask Force believes the currently available study satisfies the batch equilibrium data requirement, and that no furthertesting is necessary.
•Hydrolysis (835.2120) On page 35 ofthe EFED internal memorandum dated March 18, 2014, the Agency states that existing hydrolysis data will be "re-reviewed." EPA indicated thatthe currently available hydrolysis study is under review. The TM/MBCTask Force believes thatthe currently available study adequately satisfies the data requirement, and that no furthertesting is necessary.

In addition to conducting a hydrolysis study at astandard temperature of20 or 25°C, EPA also indicated that it has an anticipated data need for a non-guideline hydrolysis study conducted at 35°C. EPA has not provided a rationale for requesting this additional hydrolysis testing, nor, exceptfor avague reference tothe PRZM-GW model, has EPA indicated how it intendsto use these data. Model inputs for hydrolysis typically include hydrolysis rates atthree different pHs (4-5, 7, and 9), but do not include hydrolysis rates at differenttemperatures. Since 35°( is notan environmentally relevant temperature, particularlyfor groundwater, the TM/MBCTask Force sees little regulatory need for conducting an additional, high temperature hydrolysis study.

•Aerobic Soil Metabolism (835.4100) The Preliminary Problem Formulation indicatesthat an acceptable study conducted with benomyl is available and that no additional data are required. According tothe information provided in the Preliminary Problem Formulation, in this study, benomyl was rapidly converted to MBC, and the degradation of MBC was clear in this study. Therefore, it is notclear why EPA is requesting additional aerobic soil metabolism data.

The EPA internal memorandum B. Montegue 

### eta/to R. Wassem 

### eta/dated March 18, 2014 (OP Barcodes 0413007 and 0480778) on page 5 states that, "In the environment,TM [thiophanate-methyl] is expected to degrade rapidly to its primary degradate methyl2-benzimidazolylcarbamate (MBC)" and that "

...the half-life for conversion from TM to MBC may be from less than one day to several days by various environmental pathways

..." The document continues on page 10-11with, "Rapid degradation [of TM] to MBC is expected based on the short half-live observed in aerobic soil and anaerobic aquatic systems via biotic and abiotic processes" and that "No evidence has been presented to refute this assumption that rapid conversion to MBC will occurfrom TM applied to soils ortransportedtowater bodies." Also on page 37 ofthe March 18, 2014 EFED internal memorandum, Table 8 states that no further aerobic soil metabolism data are necessary for carbendazim since an MBC half-life in soil was calculated based on an acceptable benomyl study (MRIO 41255801). Based on this information, and consideringthe well-studied rapid degradation ofthiophanate methyl (and benomyl) to carbendazim the TM/MBCTask Force proposes the Agency can rely on TM and benomyl aerobic soil metabolism data to support carbendazim.

•AerobicAquatic Metabolism (835.4200) Table 8, page 37 in the EFEO internal memorandum dated March 18, 2014 states that an "acceptable" study exists (MRIO 41291501). Although the studywas conducted with benomyl, the compound rapidly degrades to carbendazim (as does thiophanate-methyl) and a MBC decline rate was calculated.EPA is requesting repeat aerobic aquatic metabolism testing in three systems. However, the guidelines only require aerobic aquatic metabolism testing in twowater-sediment systems. EFED has not provided a rationale as to why it is proposingto request repeat aerobic aquatic metabolism testing in three separate systems, particularly since an acceptable study on MBC is already available.

The Preliminary Problem Formulation in the docket indicates an acceptable aerobic aquatic study, conducted with benomyl, is already available for MBC. Based on information provided in the Preliminary Problem Formulation document, benomyl was rapidly converted to MBC (in less than one day), and the metabolism of MBC was followed in this study, with reported half-lives of23 and 61 days; EFED has already calculated an upper goth percentile confidence limiton the mean of 100 days using these data. Therefore, it is unclear why EPA is requesting additional data using three test systems. EPA has also specified that it is requesting testing in one system with a pH <6.0, one system with a pH <6.3, and one system with a pH >7.5. However, EPA has notexplained its rationale for requesting testing with water-sediment systems with these specific pH values (otherthan indicatingthat MBC expected to be
more stable at acidic pHs). However, this rationale relates more to abiotic degradation than microbiallymediated degradation. However, even ifMBC is more stable at acidic pH values, EPA has notexplained its rationale fortestingwith systems with pH values of<6.0 and <6.3.

•AnaerobicAquatic Metabolism (835.4300) As above, Table 8 page 37 in the EFED internal memorandum dated March 18, 2014, states that existing anaerobic aquatic metabolism data (MRID 41137701) is acceptable and that although the study
was conducted with benomyl, the compound rapidly degrades to carbendazim (as does thiophanatemethyl) and a MBC decline rate was calculated.

EPA is requesting repeat anaerobic aquatic metabolism testing in three systems. However, the guidelines only require anaerobic aquatic metabolism testing in two water-sediment systems. EFED has not provided a rationale as to why it is proposingto request repeat anaerobic aquatic metabolism testing in three separate systems, particularly since an acceptable study on MBC is already available.

The Preliminary Problem Formulation indicates an acceptable anaerobic aquatic metabolism study, conducted with benomyl, is already available for MBC. Based on information provided in the document, benomyl was rapidly converted to MBC, and the metabolism of MBC was followed in this study. The results ofthis study indicate that MBC is essentially stable under anaerobic aquatic conditions. Therefore, it is unclearwhy EPA is requesting additional data using three test systems, particularly since the updated environmental fate testing guidelines only require testing in two watersediment systems. Since MBC was stable in the available study underanaerobic aquatic conditions, there is little point in conducting additional anaerobic aquatic metabolism testing. EPA has also specified that it is requesting testing in one system with a pH <6.0, one system with a pH <6.3, and one system with a pH >7.5. However, EPA has notexplained its rationale for requesting anaerobic aquatic metabolism testingwith water-sediment systems with these specific pH values (otherthan MBC expected to be more stable at acidic pHs). In particular, EPA has notexplained the rationale fortesting with systems with pH values of<6.0 and <6.3. Even if EFED's hypothesis about MBC being more stable under acidic pH values is correct, this hypothesis is more applicable to abiotic degradation thatthe microbially-mediated degradation that is the focus ofanaerobic metabolism testing.•Environmental Chemistry Methods and Associated ILVs for Soil and Water (83S.6200) EPA indicated that it plans on requesting environmental chemistry methods and ILVs for soil and waterfor MBC. An LC-MS/MS analytical method and validation reportfor quantitation of carbendazim (and thiophanate-methyl) in drinking water, ground water, and surface water is available for submission tothe Agency. The Limit ofQuantitation (LOQ) ofthe method for both analytes is O.OS 1-lg/liter. This method satisfies the data requirement for an environmental chemistry method in water. The TM/MBC Task Force intends to submit this method and validation to fulfill the Agency's request foran updated environmental chemistry method forwater.

Avalidated QuEChERS method for carbendazim (and thiophanate-methyl) in soil is also available. The LOQ ofthe LC-MS/MS method is 0.01 mg/kg. This method satisfies the data requirement for an environmental chemistry method in soil. The Task Force intends to submitthis method and validation tofulfill the Agency's request for an updated environmental chemistry method for MBC in soil.

• Leaching Studies forthe Following Use Scenarios: Exterior Painted Surfaces/Wood Protective Stains/RoofCoatings; Treated Textiles (Non-Guideline) The sole registrant ofanti-microbial uses indicates data are available to address the anticipated data need for exterior painted surfaces/wood protective stains/roofcoatings. The registrant is currently evaluatingthe marketfor MBC in the textile industryand the anticipated data need for leaching studies in treated textiles should be placed on reserve while the use pattern is clearly defined.
AnticipatedEcological Effects Data NeedsforMBC

EFED's proposed data requirements for MBC include aquatic planttoxicity, honey bee acute oral and larval toxicity, and chronic whole sedimenttesting with aquatic invertebrates.
•Aquatic PlantToxicity (8S0.4400, 4SOO, 4SSO) Afull battery ofaquatic planttesting is available forTM. Results ofthese studies indicate that ECSO values and NOECs for algae and a representative aquaticvascular plant (Lemna) are well above (by
more than an order ofmagnitude) the aquatic EECs for bothTM and MBC. Therefore, the Task Force
sees little regulatoryvalue in conducting afull battery of non-targetaquatic planttestingfor MBC. The TM/MBCTask Force proposes to conducttesting with a representative aquaticvascular plant (Lemna gibba) and the most sensitive algal species tested with TM (Navicula pellicosa). The TM/MBCTask Force requests thattestingwith additional algal species be placed on reserve pending the results ofthese initial tests. Ifthe results ofthe initial tests with MBC are consistent with the available results for testing with TM, the TM/MBCTask Force sees little point in conducting additional non-target aquatic planttestingwith MBC.

• Honey Bee Acute Oral Toxicity (OECD 213) An acute contact toxicity ofcarbendazim to honey bee (MRID 001S469S) resulted in a "practically non-toxic" classification (i.e., > SO 1-lg ai/bee). Based on these data, along with considering thatthiophanate-methyl has an acute contacttoxicityto honey bee of>100 1-lg ai/bee ("practically nontoxic") (MRID 400S3209) and an acute oral toxicityto bees of>114 1-lg ai/bee (practically non-toxic, see TM section on honey bee studies above), itcan be inferredthatthe acute oral toxicity ofMBC to honey bees would be in the area of**~SO** j..lg ai/bee and therefore classified as practically non-toxic. Considering the available data on MBC and TM overall, there is little regulatoryvalue in conducting an acute oral toxicity studywith MBC on bees. The TM/MBCTask Force has notseen data that support EPA'scontention that acute contacttoxicity is not always a reliable indicatorofacute oral toxicity; however, in the case ofTM, the acute contact and acute oral toxicity data are consistent, and indicate very low toxicityto bees, and there is no reason to suspect thatthe lowtoxicity exhibited to bees by MBC in the acute contact study would notalso be exhibited in an acute oral toxicity study.

• Honey Bee Larval Toxicity (OECD 237) As withTM, ifa compound is considered practically non-toxicto honey bees exposed via contact and oral routes, the information is sufficientto predict similarly lowtoxicityto bee larvae. It is not clear why EPA believes that it needs both a honeybee larval toxicitystudy and an acute oral toxicity study with MBC when all the available data indicate that both TM and MBC display lowtoxicityto bees. At this time, it seems appropriate to place this study on reserve untilthe available data on MBC and TM are reviewed. In particular, ifan acute oral honey bee toxicity study is conducted with MBC and is consistent with available data indicating lowtoxicity of MBC and TM to bees, as expected, then the TM/MBCTask Force sees little regulatoryvalue in generating data on the toxicity of MBC to larval bees.

• Whole Sediment Chronic ToxicityTest forAquatic Invertebrates (Non-Guideline) The EFED Preliminary Problem Formulation document indicates that EPA anticipates the need for sedimenttoxicitytesting on both freshwater and marine species (guidelines 850.1735 and 850.1740). EPA has not provided a rationale orjustification for requesting sedimenttoxicitytesting on both freshwater and marine organism, so it is notclear whythe Agency anticipates this data need. The available data on freshwater and estuarine-marine invertebrates indicatesthat representative freshwater invertebrate species are more sensitive to MBC than representative estuarine-marine invertebrates. Therefore, should the Agency require sediment studies, theTM/MBCTask Force proposes to initially conduct sedimenttoxicitytestingwith a representative freshwater species and placingthe requirementfortestingwith estuarine-marine species on reserve pending the results of testing with afreshwater species. Ifthe results ofsedimenttoxicitytesting with a representative freshwater species indicates thatthe toxicity of MBC to sediment-dwelling organisms is less than the toxicity of MBC to representative freshwater pelagic invertebratesthat have already been tested (e.g., daphnids), then the TM/MBCTask Force sees little point in conducting sedimenttoxicitytestingwith an estuarine-marine species given that MBC has already been shown to be less toxicto representative estuarine-marine invertebrates than to representative freshwater invertebrates.
Anticipated ToxicologyandExposure Data NeedsforMBC

HED's proposed data requirements for MBC include an immuntoxicitystudy and various exposure studies depending upon the use pattern.
•lmmunotoxicity (870.7800) An extended one generation rat reproduction study with MBC is currently underway. The following immunotoxicity parameters are measured in the study: white blood cell counts and spleen and thymusweights and histopathology. The anticipated data need for an immunotoxicity study with MBC should be placed on hold pendingthe review and evaluation ofthe rat reproduction study.
•Occupational Handler Dermal and Inhalation Exposure Applying Paint/Stain (Airless Sprayer, Low Pressure Handwand and Brush/Roller) (875.1200/875.1400) The registrant intends to supply this information via its membership in the American Chemistry Council's (ACC) Antimicrobial Exposure Assessment Task Force II (AEATF II).• Occupational Dermal and Inhalation for Pouring Liquid and/orSolid Material Preservatives Formulations (Paint/Stains, Slurries) (875.1200/875.1400) The registrant intendsto supply this information via its membership in the American Chemistry Council's (ACC) Antimicrobial Exposure Assessment Task Force II (AEATF II).

• Residential Handler Dermal and Inhalation Exposure Applying Paint/Stain (Airless Sprayer and Brush/Roller) (875.1200/875.1400) The registrant intends to supplythis information via its membership in the American Chemistry Council's (ACC) Antimicrobial Exposure Assessment Task Force II (AEATF II).

• Product Use forApplying Paints/Stains (875.1700) The registrant intends to supply this information via its membership in the American Chemistry Council's (ACC) Antimicrobial Exposure Assessment Task Force II (AEATF II).

• Product Use Informationfor Pouring Liquid/Solid Material Preservative Formulation (875.1700) The registrant intends to supply this information via its membership in the American Chemistry Council's (ACC) Antimicrobial Exposure Assessment Task Force II (AEATF II).

• IndoorSurface Residue Dissipation for Plastic Toys and Textiles (875.2300) The registrant is reassessing the role of MBC in the textile market and intends to limitthe use of MBC products in plastic articles which are notfortoys. This anticipated data need should be placed on
reserve while the use pattern is clearly defined.
Regarding Benefits ofThiophanate-methyl and Carbendazim
Thiophanate-methyl belongs tothe benzimidazole class ofchemistry (FRAC Code 1) and is the only fungicide in the class currently registered for use in the United States. As such, it is avaluable tool in Integrated Pest Management programs where fungicides with different modes ofaction are recommended to reduce the potential for disease resistance. There is acontinued need forthe compound in crop production, particularly minor use crops, as noted by various projects undertaken by IR-4.

Carbendazim is one ofthefew broad spectrum fungicides available for use in the paints and coatings industry. Atthis point in time, water-based dispersion concentrates with carbendazim are the leading products used by paint and coating manufacturers. This is also the case for adhesives and concrete/stucco mixtures. Formulations based on dispersion technology are easily incorporated into various manufacturing processes; and, because they are water-based, avoid additional loading of volatile organic compounds (VOC's) into the air. Carbendazim is rarely used as the sole active ingredient and typically acts with otherfungicides to provide awide spectrum ofactivityagainst fungal attack in various matrices. Where currently approved fungicides have specific "gaps" in microbial control, the addition ofcarbendazim reduces overall product use rates and provides all encompassing fungal control..
Lastly, theTM/MBCTask Force is particularly interested in receiving the Data Evaluation Records (DERs) for the existing reviewed studies that are now included in the list ofanticipated data needs and would like the opportunityto meetwith the EPA tofully describe the use patterns associated with thiophanate-methyl and carbendazim and address any questionsthe Agency may have in this area.Thank you forthis opportunityto provide comments on the Preliminary Work Plan. Please feel free to contact me should you have any questions or comments on our proposals.

cc: TM/MBCTask Force 

# il **~** On the behalfof:

John J. Wrubel Chairman TM/MBCTask Force