Docket Number: EPA-HQ-OPP-2011-0613

www .regulations.gov



## Methylene Bis(Thiocyanate) Amended Final Work Plan Registration Review December 2012

Case Number: 2415

Approved By:

Acting Director, Antimicrobials Division

Date:Docket Number: EPA-HQ-OPP-2011-0613 www.regulati ons.gov

2 Methylene Bis(Thiocyanate) AMENDED FINAL WORK PLAN

Introduction

This document amends the Final Work Plan (FWP) for the registration review of methylene bis(thiocyanate) (MBT)

. Since the publicat i on of the June 2012 Final Work Plan, the Agency has determined that certain data requirements identified to support the registration r e view of MBT in the Product Chemistry, Environmental Fate, and Ecological Effects Scoping Document in Support of Registration Review of Methylene bis(thiocyanate) were inadvertently omitted in the FWP. This document amends the June 2012 FWP to include the following studies among the data identified as needed for registration review:

• Non-guideline study: Chronic sediment toxicity test (marine invertebrate)

• 835.1110: Activated Sludge Re spiration Inhibition
Also, please note that on June 27, 2012, EPA announced certain revisions in harmonized guideline series 850 - Ecological Effects Tests - including remova l of the Tier designation on 850.5400 (Algal Toxicity). For more information s ee "Final Test Guide lines; OCSPP 850 Series; Notice of Availability" 77 FR 38282, June 27, 2012. http://www.regulations.gov/#!docum entDetail;D=EPA-HQ-OPPT-2009-0154-0028 . Based on these changes, the Algal Toxic ity study (GLN 850.5400) anticipated as required in the PWP and FWP will be replaced by the following harmonized guidelines:

• 850.4500: Algal Toxicity

• 850.4550: Cyanobacteria (Anabean a flos-aquae) Toxicity

Unless otherwise stated by the Agency, all other elements of the Agency's June 2012 Methylene Bis(Thiocyanate) FWP remain unchanged.Docket Number: EPA-HQ-OPP-2011-0613 www.regulati ons.gov

3 Summary of Data Requirements
A summary table of the data required to s upport the registration review of methylene bis(thiocyanate) is presented below.
Data Requirements for the Registrati on Review of MBT (PC Code 068102)

Guideline Number Anticipated Data Requirement Test Material Estimated Timeframe (Measured in months from DCI receipt) 875.1700 Product use information (handler) TGAI 12 875.2700 Product use information (post-application) TGAI 12 875.2800 Description of human activity TGAI 12 875.1200 Dermal indoor exposure TGAI 24 875.1400 Inhalation indoor exposure TGAI 24

875.1600 Application exposure data reporting and calculations TGAI 24 875.2900 Data reporting and calculations TGAI 24 875.2500 Inhalation exposure TGAI 24 875.2300 1 Indoor surface residue dissipation TGAI 24 835.2240 Photodegradation in water (at pH 5) TGAI 12 835.1240 Adsorption/Desorption Study TGAI 12 835.4300 Aerobic Aquatic Metabolism Study TGAI 12 835.4400 Anaerobic Aquatic Metabolism Study TGAI 12 850.1400 Fish early-life stage toxic ity test (freshwater) TGAI 12

850.4400 Aquatic plant toxicology test using Lemna spp., Tier II TGAI 12

850.4500 2 Algal Toxicity TGAI 12 850.4550 2 Cyanobacteria (Anabeana flos-aquae) Toxicity TGAI 12 850.3020 Honey bee acute contact toxicity TGAI 12 850.3030 Honey bee toxicity of residues on foliage TGAI 12

1 The anticipated DCI will provide that a protocol must be submitted for review and approval by the Agency prior to initiating this study.
2 Results for studies conducted with MB T for (i) the freshwater green alga, Selenastrum capricornutum , (ii) the freshwater diatom, Navicula pelliculosa , (iii) the marine diatom, Skeletonema costatum , and (iv) the cyanobacteria species Anabaena flos-aquae , must be submitted to satisfy this requirement. Final 850 guidelines for the algal testing were posted in June 2012 after posting of the FWP. The Public Draft OP PTS 850.5400 Algal Toxicity guideline was split into two separate guidelines and renu mbered with the cyanobacteria species separated into OCSPP 850.4550 and the other three species under OCSPP 850.4500.Docket Number: EPA-HQ-OPP-2011-0613 www.regulati ons.gov

4

Guideline Number Anticipated Data Requirement Test Material Estimated Timeframe (Measured in months from DCI receipt)

850.1735 3,4,5 Whole sediment acute toxicity invertebrates (freshwater) TGAI 12

850.1740 3,6,6 Whole sediment acute toxicity invertebrates (marine) TGAI 12

TM 100.4 TM 100.5 1,4,6,7,8,9 Chronic sediment toxicity test (freshwater invertebrate) TGAI 12

EPA 600/R01/020 1,6,7

, 10 Chronic sediment toxicity test (marine invertebrate) TGAI 12

850.3300 11 Activated Sludge Respiration Inhibition TGAI 12 835.1110 12 Activated Sludge Sorption Isotherm TGAI 12 835.3110 13 Ready biodegradability TGAI 12

3 If the environmental fate data anticipated as being requi red for this registration review demonstrate that the MBT does not sorb to sediment ( i.e . all of the following conditions are met: K d <50, K oc <1000, and K ow <3) or if it does sorb to sediment but the half-life of MBT in the sediment is greater than 10 days or if less than 10 days but there is known reproduction concerns ( e.g ., pore water concentrations are expected to be greater than a chronic invertebrate NOAEC generated from a water column test or greater than 0.1 times an acute invertebrate EC 50 or LC 50 generated from a water column test), then the registrant may request that the Agency waive the acute sediment studies.
4 Results from studies using two species (an amphipod and a chironomid) must be submitted to satisfy this requirement.
5 The preferred sediment is formulated, guidance for the formulated sediment can be found in OECD 218 SedimentWater Chironomid Toxicity Test using Spiked Sediment. 6 Results from a study using an amphipod species must be submitted to satisfy this requirement.
7 If the environmental fate data anticipated as being requi red for this registration review demonstrate that the MBT does not sorb to sediment ( i.e . all of the following conditions are met: K d <50, K oc <1000, and K ow <3) or if it does sorb to sediment and all of the following conditions are me t (1) the half-life of MBT in the sediment is less than equal to 10 days and (2) the NOAEC of the acute sediment test is above environmental exposure concentrations and 0.1 times the acute sediment EC 50 or LC 50 is above environmental exposure con centrations, then the registrant may request that the Agency waive the chronic sediment studies. 8 EPA has published Agency-wide gu idance: Methods for Measuring the Toxicity and Bioaccumulation of Sediment-Associated Contaminants with Freshwater In vertebrates, EPA 600/R-99/064 available on-line at http://water.epa.gov/polwaste/sediments/cs/freshfact.cfm. 9 Based on test variability for the endpoints of concer n and the need to establish a NOAEC/LOAEC the following number of replicates and test animals are recommended: for the midge test with C. dilutus 16 replicates containing 12 test organisms each (12 replicates at test initiation; 4 added at 10 days fo r auxiliary males); for the freshwater amphipod H. azteca test of 12 replicates per treatment (4 for 28-d survival and growth and 8 for the remainder of the test) with 10 neonates per replicate. 10 EPA has published Agency-wide guidance: Method for As sessing the Chronic Toxicity of Marine and Estuarine Sediment-associated Contaminants with the Amphipod Leptocheirus plumulosus EPA 600/R-01/020 available online at http://water.epa.gov/polwaste/sediments/cs/leptofact.cfm

. 11 EPA has a published final guideline for this study. The Agency anticipates codifying this study in 40 CFR 158(W) in the near future. OECD Test Guideline 209 can also be used as guidance for this study, available online at http://www.oecd-ilibrary.org/content/book/9789264070080-en

. 12 EPA has a published final guideline for this study. The Agency anticipates codifying this study in 40 CFR 158(W) in the near future.Docket Number: EPA-HQ-OPP-2011-0613 www.regulati ons.gov

5

Guideline Number Anticipated Data Requirement Test Material Estimated Timeframe (Measured in months from DCI receipt)
835.3220 13 Porous Pot Test TGAI 12

835.3240 13 Simulation Test – Aerobic Sewage Treatment: A. Activated Sludge Units TGAI 12

835.3280 13 Simulation Tests to Assess the Biodegradability of Chemicals Discharged to Wastewater TGAI 12

13 EPA has published final guidelines for four biodegradation studies, the biodegradation study required for MBT is based on results of an Activated Sludge Respiration Inhi bition test. The Agency anticip ates codifying these studies in 40 CFR 158(W) in the near future.United States Chemical Safety June 2012 Environmental Protection and Pollution Prevention Agency (7510P)



# Methylene Bis(Thiocyanate) Registration Review: Final Work Plan June 2012Docket Number: EPA-HQ-OPP-20II-0613 www.regulations.gov



## Methylene Bis(Thiocyanate) Registration Review: Final Work Plan June 2012

Case # 

## 2415

Approved By :

oan Harrigan- arrelly Director, Antimicrobials Division

Date:

I 

# 7

2 of 

### 11Docket Number: EPA-HQ-OPP-2011-0613 www.regulations.gov

3 of 11 Methylene Bis(Thiocyanate) Registration Review Team

Human Health & Environmental Effects Nathan Mottl Steven Malish Jonathan Chen Srinivas Gowda Najm Shamim William Erickson

Risk Management Rebecca von dem Hagen Lance Wormell

Office of General Counsel Philip Ross

________________________________________ Supporting documents for the Methylene Bis(Thiocy anate) Case may be found in the registration review docket EPA-HQ-OPP-2011-0613 located on the internet at www.regulations.gov

.Docket Number: EPA-HQ-OPP-2011-0613 www.regulations.gov

4 of 11 Introduction
This is the Final Work Plan (FWP) of the Environmental Protection Agency (EPA or “the Agency”) for the registration review of methylene bis(thiocyanate) (Case 2415). The work plan includes the expected registration review time line. The work plan also addresses public comments received concerning the Preliminary Wo rk Plan (PWP) in the Summary Document which was posted in the methylene bis(thiocyanat e) registration review docket, and any other comments concerning the initial docket postings. The Summary Do cument provided information on what EPA knows about the pesticide and what additional risk analyses and data or information the Agency believes are needed to make a registration review decision.
The Agency is implementing the registration revi ew program pursuant to Section 3(g) of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and will review each registered pesticide every 15 years to determine whether it continues to meet th e FIFRA standard for registration. Changes in science, public policy an d pesticide use practices will occur over time. The registration review program is intended to ma ke sure that, as the ability to assess risk evolves and as policies and practi ces change, all registered pestic ides continue to meet that statutory standard. The public pha se of registration review begins when the initial docket is opened for each case. Information on this program is provided at: http://www.epa.gov/oppsrrd1/registration_review/.
The Methylene Bis(Thiocyanate) Case (Case Nu mber 2415) includes one active ingredient, PC Code 068102. The first product containing methyl ene bis(thiocyanate) (MBT) as an active ingredient was registered in the United Stat es in 1949. Currently, there are 40 MBT products registered with EPA. Products containing MBT are registered for use as material preservatives for incorporation into products such as adhesive s, coatings, fuels, metalworking cutting fluids, textiles, plastic products, resin emulsions, paints , paper products and various other products. Products containing MBT are also registered as microbiocides for use in pulp/paper mills, cooling water systems (recirculating), oil fiel d operations, air washer systems, brewery pateurizers, hydrotesting, leat her processing and industrial wa ter supply systems. MBTcontaining products are also register ed for use as wood preservatives.
No tolerances or exemptions from tolerances have been established for MBT. MBT is cleared as an indirect additive in food cont act substances for slimicides in paper and paperboards by FDA (29 CFR 176.300). Also, FDA has cleared the use of MBT in a dhesives under a threshold of regulation; MBT can only be used in packaging materials for dry f oods at a level not to exceed 0.01% active ingredie nt (21 CFR 170.39).
The Agency completed a Reregistration E ligibility Decision (RED) for methylene (bis)thiocyanate in 1997. At the time of the RED, the Agency was unable to make a reregistration decision on MBT’s use as a wood preservative, in leather processing liquid and products and in paint due to th e lack of data. The Agency has since received the 90-day inhalation study (MRID 45366301) and intends to incorporate it in th e anticipated risk assessments for the registration review of MBT.Docket Number: EPA-HQ-OPP-2011-0613 www.regulations.gov

5 of 11 The methylene (bis)thiocyanate PWP was published on December 21, 2011 and the 60-day comment period ended on February 21, 2012. Th e PWP and supporting documents are available on www.regulations.gov docket number EPA-HQ-OPP-2011-0613.
Comments Received on the Preliminary Work Plan
The Agency received no comments during the pu blic comment period on the initial docket. In the PWP, the Agency solicited comments on speci fic topics: environmental justice, water body impairment, trade irritants, a nd structure activity relationships . No comments or information were received during the public comme nt period concerning these issues.
Therefore, the data needs, work plan, and time line described in the PWP remain as they were presented initially. Further, this document ma kes final the work plan for the methylene bis(thiocyanate) registration review process.
Risk Assessments and Anticipated Data Needs
The Agency anticipates the need to conduct a comprehensive ecological risk assessment, including an endangered species risk assessment, for all uses of methylene (bis)thiocyanate. The Agency also anticipates the need to conduct a human health risk assessment. The Agency anticipates needing additional data for use in conducting the registration review for MBT.
Ecological Risk:

 A quantitative ecological risk assessment was not performed for MBT at the time of the RED. For registration review, the Agen cy anticipates the need to conduct a comprehensive ecological risk assessment fo r MBT, including an endangered species assessment.

 The Agency anticipates the need to require the following additional ecological data for use in the registration review of methylene (bis)thiocyanate.
850.1400 -- Fish early-life stage to xicity test (freshwater) 850.4400 -- Aquatic plant toxicology test using Lemna spp., Tier I 850.5400 -- Algal Toxicity Tier I and Tier II 850.3020 -- Honey bee acute contact toxicity 850.3030 -- Honey bee toxicity of residues on foliage 850.1735 -- Whole sediment acute toxici ty invertebrates (freshwater) 1 850.1740 -- Whole sediment acute toxi city invertebrates (marine) 1 Special Study -- Chronic sediment toxi city test (freshwater invertebrate) 1

 The Agency anticipates the need to require the following additional environmental fate data for use in the registration revi ew of methylene (bis)thiocyanate.

1 If the environmental fate data anticipated as being requi red for this registration review demonstrate that the halflife of the MBT in the sediment is greater than 10 days and if any one of the following conditions are met (1) Kd <50, (2) Koc <1000, or (3) Kow <3, then the registrant may request that the Agency waive the sediment studies.Docket Number: EPA-HQ-OPP-2011-0613 www.regulations.gov

6 of 11 835.2240 -- Photodegradation in water (at pH 5) 835.1240 -- Adsorption/desorption 835.4300 -- Aerobic aquatic metabolism 835.4400 -- Anaerobic aquatic metabolism 850.6800 -- Modified activated sludge , respiration inhibition test 2 835.3110 -- Ready Biodegradability 2 835.3220 -- Porous Pot Test 2 835.3280 -- Simulation Tests to Assess the Biodeg radability of Chemicals Discharged to Wastewater 2 835.3240 -- Simulation Test – Aerobic Sewage Treatment: A. Activated Sludge Units 2 Special Study -- Leachability of wood pres ervatives used in contact with water

 For more information, please refer to Product Chemistry, Environmental Fate, and Ecological Effects Scoping Document in Suppor t of Registration Re view of Methylene bis(thiocyanate) , located in the docket.

Human Health Risk:

 The most recent human health risk assessmen ts for methylene (bis)thiocyanate were completed in 1997, in support of the RED.

 The Agency anticipates the need to require the following additional human health data for use in conducting occupational, residential, dietary and aggregate risk assessments for the registration review of methylene (bis)thiocyanate.
875.1200 -- Dermal indoor exposure 875.1400 -- Inhalation indoor exposure 875.1600 -- Application exposure data reporting and calculations 875.2300 -- Indoor surface residue dissipation 875.2500 -- Inhalation exposure 875.2800 -- Description of human activity 875.2900 -- Data reporti ng and calculations 875.1700 -- Product use information (handler) 875.2700 -- Product use information (postapplication)

 The Agency anticipates the need to conduct an aggregate risk assessment based on the potential for residential, diet ary and drinking water exposure.

2 The results of the Activated Sludge Respiration Inhibitio n Test (ASRI) that is expected to be required would determine which of these three biodegradation tests would be anticipated to be required. If the ASRI test EC 50 is less than or equal to 20 mg/L, then either the Biodegradation in Activated Sludge Study or Simulation Test – Aerobic Sewage Treatment: A. Activated Sludge Units or the Porous Pot Test would be anticipated to be required. If the ASRI test EC 50 is greater than 20 mg/L, then the applicant would choose to conduct either: (i) Ready Biodegradability or (ii) Biodegradation in Activated Slu dge or Simulation Test – Aerobic Sewage Treatment: A. Activated Sludge Units or the Porous Pot Test. If the antimicrobial passes the ready biodegradability study, then no further testing would be expected to be required. If , however, the antimicrobial fails the ready biodegradability study, then the Biodegradation in Activated Sludge or Simulation Test – Aerobic Sewage Treatment: A. Activated Sludge Units, or the Porous Pot study would be expected to be required.Docket Number: EPA-HQ-OPP-2011-0613 www.regulations.gov

7 of 11  For more information, please refer to Methylene Bis Thiocyanate (MBT): Human Health Risk Assessment Scoping Document in Support of Registration Review , located in the docket.
Product Chemistry:

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

 For more information, please refer to Product Chemistry, Environmental Fate, and Ecological Effects Scoping Document in Suppor t of Registration Re view of Methylene bis(thiocyanate) , located in the docket.

Incidents:
Ecological:

 No methylene (bis)thiocyanate ecological incidents have b een reported in the Agency’s Ecological Incident Information System (EIIS).

Human Health:

 There are nine MBT-specific incidents that have been reported in the Office of Pesticide Program Incident Data System (IDS). Most of the incidents were as a result of acute/short term inhalation exposure. Workers reported ir ritation and burning of the lung tissue as well as airway and vocal cord dysfunction. Long-term respirator y irritation has been reported in workers working with MBT containing products. There have also been skin irritation incidents reported.
Endangered Species
The Agency has not conducted a risk assessmen t that supports a complete endangered species determination for methylene (bis)thiocyanate. The ecological risk assessment planned during registration review will allow th e Agency to determine whether methylene (bis)thiocyanate’s use has 'no effect' or 'may affect' federally listed thre atened or endangered species (listed species) or their designated critical habita ts. When an assessment concludes that a pesticide’s use 'may affect' a listed species or its designated critical habitat, the Agency will consult with the U.S. Fish and Wildlife Service and/or National Mari ne Fisheries Services (the Services), as appropriate.
Endocrine Disruptor Screening Program
As required by FIFRA and FFDCA, EPA reviews num erous studies to asse ss potential adverse outcomes from exposure to chemicals. Collectiv ely, these studies includ e acute, subchronic and chronic toxicity, including asse ssments of carcinogenicity, ne urotoxicity, developmental, reproductive, and general or systemic toxicity. These studies include endpoints which may be susceptible to endocrine influe nce, including effects on endocri ne target organ histopathology, organ weights, estrus cyclicity, sexual maturatio n, fertility, pregnancy rates, reproductive loss,Docket Number: EPA-HQ-OPP-2011-0613 www.regulations.gov

8 of 11 and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and chronic studies that assess gr owth, developmental and reprod uctive effects in different taxonomic groups. As part of its 1997 Rere gistration Eligibility Decision for MBT decision, EPA reviewed these data and select ed the most sensitive endpoints for relevant risk assessment scenarios from the existing hazard database. However, as required by FFDCA section 408(p), methylene (bis)thiocyanate is subject to the endo crine screening part of the Endocrine Disruptor Screening Program (EDSP).
EPA has developed the EDSP to determine whet her 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 ot her such endocrine effect s as the Administrator may designate.” The EDSP employs a two-tiered approach to making th e statutorily required determinations. Tier 1 consists of a battery of 11 screening assays to identify the potential of a chemical substance to interact with the estrog en, androgen, or thyroid (E, A, or T) hormonal systems. Chemicals that go th rough Tier 1 screening and are found to have the potential to interact with E, A, or T hormonal systems will proceed to the next stag e of the EDSP where EPA will determine which, if any, of th e Tier 2 tests are necessary base d on the available data. Tier 2 testing is designed to identify a ny adverse endocrine-related eff ects caused by the substance, and establish a dose-response relationship between the dose and the E, A, or T effect.
Under FFDCA section 408(p), the Agency must scre en all pesticide chemicals. Between October 2009 and February 2010, EPA issued test orders/dat a call-ins for the firs t group of 67 chemicals, which contains 58 pesticide active ingredients and 9 inert ingredients. Methylene (bis)thiocyanate is not among the group of 58 pestic ide active ingredients on th e initial list to be screened under the EDSP. Accordingly, as part of registration review, EPA will issue future EDSP orders/data call-ins, requiring the submi ssion of EDSP screening assays for methylene (bis)thiocyanate. For further information on the st atus of the EDSP, the policies and procedures, the list of 67 chemicals, future lists, the test guidelines and the Tier 1 screening battery, please visit our website: http://www.epa.gov/endo/.

Timeline
EPA has created the following estimated timeline for the completion of the methylene bis(thiocyanate) registration review.

Anticipated Schedule Activities Estimated Month/Year Phase 1: Opening the docket Open Public Comment Period for Docket December 2011 - Completed Close Public Comment Period for Docket February 2012 - Completed Phase 2: Case Development Develop Final Work Plan (FWP) June 2012 - Completed Issue DCI June 2013 Data Submission June 2015Docket Number: EPA-HQ-OPP-2011-0613 www.regulations.gov

9 of 11 Open Public Comment Period for Prelim inary Risk Assessments December 2016 Close Public Comment Period for Prelim inary Risk Assessments January 2017 Phase 3: Registration Review Decision Open Public Comment Period for Pro posed Reg. Review Decision June 2017 Close Public Comment Period for Pro posed Reg. Review Decision August 2017 Final Decision and Begin Post-Decision Follow-up 2017 Total (years) 6

Next Steps

A DCI will be developed regarding the data needs listed under the “Risk Assessments and Anticipated Data Needs” section of this document. The Agency expects to issue the DCI in June 2013. The Agency anticipates the need to conduct human health and ecological risk assessments for all uses of MBT.Docket Number: EPA-HQ-OPP-2011-0613 www.regulations.gov

10 of 11 Summary of Anticipated Data Requirem ents – Methylene (Bis)Thiocyanate

The table below summarizes anticipated data needs for the Methylene Bis(Thiocyanate) Case in this document (Final Work Plan), Product Chemistry, Environmental Fate, and Ecological Effects Scoping Document in Support of Regist ration Review of Methylene bis(thiocyanate), and Methylene Bis Thiocyanate (MBT): Human Hea lth Risk Assessment Scoping Document in Support of Registration Review.

Guideline Number Anticipated Data Requirement Test Material Estimated Timeframe (Measured in months from DCI Receipt)
875.1700 Product use information (handler) TGAI 12
875.2700 Product use information (postapplication) TGAI 12
875.2800 Description of human activity TGAI 12
875.1200 Dermal indoor exposure TGAI 24
875.1400 Inhalation indoor exposure TGAI 24
875.1600 Application exposure data reporting and calculations TGAI 24
875.2900 Data reporting and calculations TGAI 24
875.2500 Inhalation Exposure TGAI 24
875.2300 Indoor Surface Residue Dissipation 3 TGAI 24

835.2240 Photodegradation in water (at pH 5) TGAI 12
835.1240 Adsorption/Desorption Study TGAI 12
835.4300 Aerobic Aquatic Metabolism Study TGAI 12
835.4400 Anaerobic Aquatic Metabolism Study TGAI 12
850.6800 Modified activated sludge, respiration inhibition test 4 TGAI 12

3 The anticipated DCI will provide that a protocol must be submitted for review and approval by the Agency prior to initiating this study.
4 The results of the Activated Sludge Respiration Inhibition Test (ASRI) that is expected to be required would determine which of these three biodegradation tests would be anticipated to be required. If the ASRI test EC 50 is less than or equal to 20 mg/L, then either the Biodegradation in Activated Sludge Study or Simulation Test – Aerobic Sewage Treatment: A. Activated Sludge Units or the Porous Pot Test would be anticipated to be required. If the ASRI test EC 50 is greater than 20 mg/L, then the applicant would choose to conduct either: (i) Ready Biodegradability or (ii) Biodegradation in Activated Slu dge or Simulation Test – Aerobic Sewage Treatment: A. Activated Sludge Units or the Porous Pot Test. If the antimicrobial passes the ready biodegradability study, then no further testing would be expected to be required. If , however, the antimicrobial fails the ready biodegradabilityDocket Number: EPA-HQ-OPP-2011-0613 www.regulations.gov

11 of 11 835.3110 Ready Biodegradability 4 TGAI 12

835.3220 Porous Pot Test 4 TGAI 12

835.3240 Simulation Test – Aerobic Sewa ge Treatment: A. Activated Sludge Units 4 TGAI 12

835.3280 Simulation Tests to Assess the Biodegradability of Chemicals Discharged to Wastewater 4 TGAI 12

850.1400 Fish early-life stage toxic ity test (freshwater) TGAI 12
850.4400 Aquatic plant toxicology test using Lemna spp., Tier I TGAI 12
850.5400 Algal Toxicity Tier I and Tier II TGAI 12
850.3020 Honey bee acute contact toxicity TGAI 12
850.3030 Honey bee toxicity of residues on foliage TGAI 12
850.1735 Whole sediment acute toxicity invertebrates (freshwater) 5 TGAI 12
850.1740 Whole sediment acute toxicity invertebrates (marine) 5 TGAI 12
Special Study Chronic sediment toxicity test (freshwater invertebrate) 5 TGAI 12

study, then the Biodegradation in Activated Sludge or Simulation Test – Aerobic Sewage Treatment: A. Activated Sludge Units, or the Porous Pot study would be expected to be required. 5 If the environmental fate data anticipated as being requi red for this registration review demonstrate that the halflife of the MBT in the sediment is greater than 10 days and if any one of the following conditions are met (1) Kd <50, (2) Koc <1000, or (3) Kow <3, then the registrant may request that the Agency waive the sediment studies.