UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C. 20460 OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION

December 9, 2013 MEMORANDUM: Subject: Captan- Anticipated Antimicrobial Risk Assessments and Data Needs for Registration Review PC Code: 081301 DP Barcode: 414055 Decision No.: 478164 Registration No.: 400-583, 11678-01, 19713-258, 42750-230, 66330-31 PetitionNo.: NA Regulatory Action: Registration Review Risk Assess Type: Scoping Document Case No.: 0120 TXRNo.:NA CAS No.: 133-06-02 MRIDNo.:NA 40CFR: NA**~** From:

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# PJ-t{ Timothy C. Dole, Industrial Hygienist Donna Randall, Senior Scientist

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### Sup~ta".I**iSh RA**  S Antimicrobials Division (751OP) Steven Weiss, Branch Chief

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# }rt/13 Laura Parsons, Assistant Branch

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### ~ Risk Assessment and Science Suppo ch (RASSB) Antimicrobials Division (751OP) Christina Scheltema, Chemical Review Manager Risk Management Implementation Branch 3 (RMIB 3) Pesticide Re-evaluation Division (7508P)

Captan technical grade active ingredient is currently registered for formulation into end use products for use inthe preservation ofpaints, plastics and adhesives to prevent degradation from fungi and bacteria. However, there are currently no registered antimicrobial end-use products containing captan as an active ingredient. EPA evaluated current agency science policies and risk assessment methods, updated toxicity and exposure data bases to determine the scope of work necessary for registration review ofthesetechnical labeled uses. While there are currently no registered end-use products containing captan, EPA anticipates that additional data are needed to evaluate the antimicrobial uses ofcaptan during registration review. Furthermore, EPA anticipates that the registration review risk assessment will considerthe potential Page 1 of5antimicrobial uses ofcaptan. This memo describes the anticipated data requirements and risk assessments for the antimicrobial uses ofcaptan. Human Health Data Requirements EPA anticipates that the following studies will be needed to assess human health risks for the antimicrobial uses ofcaptan.

• Indoor dermal and inhalation exposure studies (OCSPP 875.1200 and 875.1400), are anticipated as needed to assess exposures from open pouring ofwettable powder (WP) formulations during material preservation treatment ofpaints, plastics and adhesives and during the brush and roller application ofcaptan treated paints. • Outdoor dermal and inhalation exposure studies (OCSPP 875.1100 and 875.1300), are anticipated as needed to assess exposures from the airless sprayer application ofcaptan treated paints. • An indoor surface residue study (OSCPP 875.2300) is anticipated as needed to assess incidental oral exposure from toddler object to mouth contact with household items and toys made from captan treated plastics.
In addition to the exposure monitoring studies listed above, a 90 day inhalation toxicity study is typically required to assess inhalation exposures for material preservatives that are applied using openpour methods. Such a study is available for captan; however, it was previously notused to assess inhalationrisks. EPA expects to evaluate the potential use ofthis study for inhalation risk assessment during registration review.

Environmental Fate and Effects Data Requirements An ecological risk assessment for material preservative uses in paints, plastics and adhesives has notbeen conducted previously. Previous practice considered these indoor uses, with no environmental releases. These uses have been determined to potentially result in environmental releases, and under current practice risks from these environmental releases are assessed. The following scope ofwork discussion uses the review ofthe existing fate data base for captan and its major degradates discussed in the Registration Review Problem Formulationfor Captan (DocketNumber EPA-HQ-OPP-2013-0296-0003) for the conventional agricultural uses. The exposure scenarios associated with antimicrobial uses ofcaptan are very different from conventional use, where captan is applied to crops or seed or seed pieces. In conventional uses, captan parent is present much longer, until it reaches water viarunoff. EPA expects the captan degradate THPI to be the predominant residue associated with environmental exposures associated with antimicrobial uses ofcaptan. Forthe plastic material preservative use, captan is expected to be released to water through industrial manufacturing processes and undergo wastewater treatment priorto discharge to surface waters. Forthis potential antimicrobial use of captan, AD expects captan to rapidly hydrolyze and metabolize in water to form THPI, prior to exposure ofnon-target organisms. Captan leaching during in-service use ofpaint (e.g., architectural paints) and adhesives is also expected to convert to THPI due to hydrolysis and metabolism priorto exposure ofnon-target organisms. Page 2 of5The Registration Review Problem Formulationfor Captan (DocketNumberEPA-HQ-OPP2013-0296-0003) outlined fate data needed to conduct risk assessments for conventional uses. It is anticipated that the assessment ofantimicrobial uses will use the captan hydrolysis, photolysis (water and soil), aerobic and anaerobic soil metabolism, aerobic and anaerobic aquatic metabolism data, soil leaching-adsorption/desorption data and fish bioaccumulation data, and the TPHI aerobic soil and aquatic metabolism data. Several key environmental fate data for TPHI (i.e., hydrolysis [OCSPP 835-2120], aquatic photolysis [OCSPP 835-2240], and anaerobic aquatic metabolism [OCSPP 835-4400]) are not available for the aquatic exposure assessment. Inthe absence ofthese data, conservative assumptions will be made about the fate properties for THPI, including the use ofpredictive models to generate appropriate data. Additional anticipated fate data needed to conduct a risk assessment for the material preservative uses, where residuals may discharge to waste watertreatment plants (WWTPs) includes: TPHI wastewater fate (biodegradationremoval [OCSPP 835.3110, 835.3220, 835.3240, or 835.3280]) and effects (Activated Sludge Respiration Inhibition data). Itis not anticipated that activated sludge sorption isotherm data is required because its log Kow is less than 3.0. To estimate concentrations in water from in-service uses ofpaints and plastics leaching data from these types ofmaterials is anticipated as needed. The anticipated fate data gaps unique to the antimicrobial use patterns are listed in Table 1. The Registration Review Problem Formulationfor Captan (Docket Number EPA-HQ-OPP2013-0296-0003) outlined ecological effects data needed to conduct risk assessments for conventional uses. Itis anticipated that all antimicrobial uses will use TPHI acute freshwater fish and invertebrate data, chronic freshwater fish and invertebrate data, estuarine/marine mollusk data (more sensitive ofthe captan estuarine/marine species), vascular and non-vascular aquatic plant data, and rice vegetative vigor and seedling emergence data (paints and plastics uses only). In addition to the diatom study (850.4500) with captan identified as a data gap in the conventional use document, the following are anticipated ecological effect TPHI data gaps for antimicrobial uses: acute estuarine/marine mollusk data (OCSPP 850.1025 or 835.1055); acute estuarine/marine fish (OCSPP 850.1075) with a Silverside sp.; fish early life stage (OCSPP 850.1400)-usingthe more acutely sensitive freshwater orestuarine/marine species; freshwater diatom (OCSPP 850.4500); and rice seedling emergence and vegetative vigor (OCSPP 850.4100 and 850.4150) as listed in Table 1. No chronic freshwater invertebrate or chronic shrimp data is anticipated to be required because these were the least sensitive aquatic species to captan, and it is therefore unlikelythey will be the risk drivers for TPHI. Data Requirement Summary The human health and environmental fate and effects data requirements associated with the antimicrobial uses ofcaptan are summarized in Table 1. \

Page 3 of5Table 1 -Anticipated Data Needs for AntimicrobialUses ofCaptan 1 Estimated Guideline Timeframe Numbe.-2 Study Title TestMaterial3 (Months from receipt ofDCI)4 Non-GDLN Special Leaching Study5• 6 Treated article 24 835.3110 Ready Biodegradability THPI 12 835.3220 Porous PotTest THPI 12 835.3240 Simulation Test

- Aerobic Sewage THPI 12 Treatment A. Activated Sludge Units Simulation Testto Assess the 835.3280 Biodegradability ofChemicals Discharged THPI 12 to Wastewater 850.1025 or Acute Toxicity Estuarine/Marine THPI 12

850.1055 Organisms

- Mollusk 850.1075 Acute Toxicity Estuarine/Marine THPI 12 Organisms

- Fish (preferred Silverside sp.) 850.1400 Fish Early-Life Stage Toxicity Test THPI 12 (freshwater) 850.4100 Seedling Emergence

- TierII (rice)6 THPI 12 850.4150 Vegetative Vigor

- Tier II (rice)6 THPI 12 850.4500 Algal Toxicity

- Tier II (freshwater THPI 12 diatom) 850.3300 / Activated Sludge Respiration Inhibition TGAI, THPI 12 orOECD209 (ASRI/ 875.1100 Dermal OutdoorExposure8•10 TEP 36 875.1200 Dermal Indoor Exposure9•10 TEP 36 875.1300 Inhalation Outdoor Exposure·8•10 TEP 36 875.1400 Inhalation Indoor Exposure9•10 TEP 36 875.2300 Indoor Surface Residues 11 Treated article 24 l . . The ant1c1pated data requrrements hsted mth1s table are for only the ant1m1crob1al uses ofcaptan

. 2 On May 8, 2013. EPA promulgated the Final Rule establishing Data Requirements for Antimicrobial Pesticides on May 8, 2013; the regulation becomes effective on July 8, 2013. See http://www.gpo.gov/fdsys/pkg/FR-2013-05- 08/pdf /20 13-10 162.pdffor details. 3 TGAI

- technical grade active ingredient; TEP -typical end-use product; THPI

- degradate ofcaptan; treated article

- article containing captan as a material preservative. 4 Estimated timeframe allows time for review ofprotocols by EPA's Human Studies Review Board (HSRB) and /orthe Institutional Review Board (IRB). 5Anticipated to be required for paints and plastics containing captan. 6 The anticipated DCI will require the submission and EPA approval ofa protocol priorto study initiation. 7 EPA published draft guidance under guideline OPPTS 850.6800 and has since published fmal guidance for this under guideline OCSPP 850.3300: http://www.regulations.gov/#!documentDetaii;D=EPA-HO-OPPT-2009-0154- 0021

. OECD Test Guideline 209 can also be used as guidance for this study, available online at http://www.oecdilibrary.org/contentlbook/9789264070080-en

. EPA expects that the results ofthe anticipated Activated Sludge Respiration Inhibition Test (ASRI) will determine which ofthe four biodegradation tests is/are required. Ifthe 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 is required. If Page 4 of5the ASRI test EC50 is greater than 20 mg!L, then the registrant must conduct either: (i) Ready Biodegradability or (ii) a) Biodegradation in Activated Sludge orb) Simulation Test- Aerobic Sewage Treatment: A. Activated Sludge Units or c) the Porous PotTest. Ifthe 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 orb) Simulation Test- Aerobic Sewage Treatment: A. Activated Sludge Units, or c) the Porous Pot study is required. 8 Anticipated to be required to assess exposures from airless spray application ofcaptantreated paints. 9Anticipated to be required to assess exposures from open pouring ofwettable powder (WP) formulations during material preservation treatment ofpaints, plastics and adhesives and duringthe brush and roller application ofcaptan treated paints. 10 The anticipated DCI will require the submission and approval ofa protocol bythe HSRB priorto study initiation. 11 Anticipated to be required to assess incidental oral exposures from toddlers mouthing plastic toys and household objects treated with or containing captan.
Anticipated Risk Assessments EPA anticipates conducting occupational handler and post application assessments for the antimicrobial uses ofcaptan. EPA anticipates conducting newresidential risk assessments for use oftreated paints and household plastics. EPA anticipates conducting a new drinking water assessment that considers both captan parent and its THPI degradate. The previous drinking water assessment considered THPI only. EPA anticipates conducting a risk assessment for the plastic application facility site, and in-service uses ofplastics and paints (adhesives will be covered by these uses).

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