Dock e t Number EPA-HQ-OPP-2014-0175 www .re gu lati o n s . gov



# Thiabendazole Final Work Plan Registration Review

Case Number 2670 September 2014

· Approved by:

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Date: Richard P. Keigwin, Jr. Director Pesticide Re-evaluation Division 

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# -~./J Susan Lewis Director Antimicrobial s Divi s ion2INTRODUCTION This is the Env ironme ntal Protection Agency ' s (E PA or the Agency) Final Work Plan (FWP) for the registration review of t hiabend azole. This work plan addresses public comments rec eived concernin g the Preliminary Work Plan (PW P), w hi ch was posted in the thiabendazole registration review docket (EPA -HQ-OPP- 2014-0175). Thiabendazole is a systemic fungicide registered fo r u se as a seed treatment on com, soybean , dry peas , chickpeas , lent ils, and wheat; a treatm e nt of seed pieces on potatoes and sweet potatoes ; to contro l fungal diseases in mushroom c ulture; a postharvest app lication to a variety of t errestrial food and non - foo d crops; and a fungicide and preservative used in the manufacture of adhesives (no n- food), carpets, ceil ing tiles , paper products (non-food), paints and sta ins (used indoor and o utd oo r), plastics and rubber, textiles, and wallboard
. The Agency is implementing the registration review pro gram pur s uan t to Section 3(g) of the Federal Insecticide, Fungicide, and Rodenticide Act (F IFRA) , and will rev ie w each registered p estic ide every 15 years to determine whether it con tinu es to meet the FIFRA standard for registration. C hanges in science, public polic y, and pesticide u se practices occur over time . T he registration review program i s intended to make s ure t hat , as the ab ility to assess ri s k evolves and as po li c i es and practices change, all registered pesticides continu e to meet the statutory standard. The public phase of registration review begins when the initial docket is open e d for each case. Information on t h is program is prov ided on the Agenc y' s webs ite
. 1 The FWP begins with any updates since the PWP w a s i ssued. Next is a summary of substantive comment s received during the publ ic comment period fo r the PWP concerning anticipated data needs , expected ri s k assessments, or the estimated timeline identi fie d in the PWP , and a summ ary of the Agency ' s responses to those comments. This section is followe d by regis tration review planned data needs, risk assessments expected to be conduc ted, and the projected registration review tim eline for thiabendazo l e. Lastly , there is a di scuss ion of next steps. UPDATES SINCE THE PWP WAS ISSUED T he anticipated Special Study, Non-guideline for Leaching f ro m T reated Textiles has been reclassified as guideline 875.2300 Indoor Surface Re s idue Dissipation (see Table 1)
. The es tim ated t imefr ame for completion of th e Residential hand ler inhalation exposure - indoor (GLN 875.1400) and Indoor surface residue dissipati on (GLN 875.2300) were incorrectl y listed as 1 2 months in the PWP. The correct timefrarne of24 months has been updated in the list of data requirements (see Ta ble 1) in the FWP
. The Projected Registration Review Timeline in the PWP is correct and matches the 24 month tirneframe fo r data submission in this FWP (see Table 3). SUMMARY OF COMMENTS AND AGENCY RESPONSES During the 60-day public comment period on the thiabendazole PWP , which ope ned on March 28 , 20 14 and closed on May 27, 2014, the Agency rece ived six p ublic comments. Comments

1 http: //www . epa . gov/opps rrd I/registration

_ review/ 

### 3were sub mitte d by the Washingto n State P est Managem ent Resource Service , Washington State 

### University Tri-Cities; the Northwest Horticultural Council (NHC); the FIFRA Endangered Species Task Force (FESTF); the Center for Biological Diversity (CBD); Syngenta Crop Protection LLC; and Lanxess Corporation. The comments do not address the timeline described in the PWP , but they do address the planned ecological and human health risk assessments and data requirements. I n the PWP, EPA also so licite d comments on the specific topics of environmental justice, water quality concerns , and trade irritants. While no comments were made on environmental justice or water quality concerns, Syngenta and NHC commented on the importance of avoiding trade irritant issues. This section does not capture every comment made about the PWP**~or** all of the Agency 's responses. Summarized below are public comments that resulted in changes to the anticipated registration rev i ew data needs , risk assessments, or tim elin e, or are of a broader regulatory nature. Public comments and EPA re sponses in their entirety are located in the docket, EPAHQ-OPP-2014-0175. Summarized public comments and Agency responses related to the anticipated ecological risk assessment or data needs are in the EFED Respon se to Comments on the Problem Formulation for Thiabendazole and Thiabendazole Hypochloride (dated August 11 , 20 14) while those relevant to the anticipated human health risk assessment or data needs are in the documents T hiab endazole and Salts: Health Effects Division's Response to Comments on the Thiabendazole Preliminary Work Plan (PWP)for Registration Review (dated June 24, 2014 and a second memo dated August 12 , 20 14) , and those relevant to the antimicrobial registrations are in the Antimicrobial Division ' s Response to Public Comments on the Regis tration Review Preliminary Work Plan for Thiabendazole (dated August 21, 2014). 

### 1. Comments submitted by the Washington State Pest Management Resource Service on behalf of the Western Integrated Pest Management (IPM) Center in EPA-HQ OPP-2014-0715-00 10. Comment: The submitted comments provided inf ormation on use of thiabendazole in the northwest U.S., inc luding its use in IPM and agricultural benefits
. Response: The Agency thanks the Washington State Pest Management Resource Service for its comments. EPA will consider this information during the thiabendazole registration revtew. 2 . Comm ents submitted by NHC in EPA-HQ - OPP-2014-0715-0011 . Comment: NHC submitted information about the use of thiabendazole and highlighted potential trade irritant issues. Response: The Agency thanks NHC for i ts comments. EPA will consider this information during the thiabendazole registration review. 3. Comments submitted by FESTF in EPA- HQ-OPP-2014-0715-0012. Comment: FESTF identified Aibaugh, lnc and Syngenta Corporation as FE STF members entitled to rely on FESTF data.
4Response: The Agency thanks FESTF for its co mment and will consi d er thi s information during the thiabe ndazo le reg istration review. 

### 4. Co mments submitted by CBD in 

### EPA-HQ-OPP-2014 -0 715-0013. Comment: C BD 's commen ts focus on EPA's duty t o consult with the U.S. Fish and W ildlife Serv i ce and the Natio nal Marine Fis heri es Serv ice (the Services) on the registration review of thi a bendazo le in accordance with the Endangered Spec ies Act (ESA). CBD 's comments m enti o n various aspects of the risk assessment process , including use of the b est available data to d evelop endan ge red species risk asses sment s, and eval ua t ion of effec ts on endangere d and threatened species and their designated critical habit at. CBD also expresses concern regardin g th e rigor of the Agency's determinations
. Response: E P A has reviewed t he comment s from CB D o n the registration review docket opening for thiabendazole and plans to address many of the co ncern s rai sed by CBD as part of the impl eme ntatio n plan for asses s ing th e risks of pesticides to li sted species based on the recommendations of the April 2013 National Academy of Scie nces (NAS) report. EPA will address concerns specific to thiabendazole in connection with the development of its final registration review decision for thi s pesticide. In November 2013 , the EPA, along with the Services and the USDA, release d a summary of their joint Interim Ap proaches for assess in g ri sks to endangere d and t hreatened (listed) species from pesticides. T he Interim Appro ac hes were developed joint ly by the agencies in response to the NAS recommen dations and reflect a common approach to risk assessment s hared by the agencies as a way of addressing scientific differences between the EPA and the Serv i ces. The NAS report outlines recommenda t i o ns on specific scientific and technical issues related to the d eve lopment of pes ticide risk assessments t hat EPA and the Services must co nduct in connection w ith their obligations und er the ESA and F IFRA
. The j o int Interim Approac hes we re released prior to a stake holder workshop held on November 15 , 2013. In addition, the EP A presented th e joint Interim A pproaches at the December 2013 Pesticide Program Dialogue Committee (PPDC) and S t ate -FIFRA Issues Research and Evalu atio n Group (SFIREG) meetings. The agenc ies also held a stakeholder wo rks hop in Apr il2014 , allowing additional opportunities for st akeho lders to comment on the Interim Appro aches
. Additional workshops are planned to enhance stake ho lder involvement; the next workshop is scheduled for October 20 14. As part of a phased, iterative process for developing the Interim Appro aches, the agencies w ill also consider public comments on th e Interim Approaches in connection with th e deve l opme nt of upcoming registration review decisions. The details of the joint In terim App roaches are contained 

### in the white paper , Interim Appr oaches for N ational-L evel Pesticide Endangered Species Act Assessments Based on the Recommendations of the National Academy a/Scie nces Apri/2013 Report, dated November 1, 2 01 3
. Given that the agencies are continuing to develop and work toward implementation of th e Inter im App r oac h es to assess the potential risk s of pesticides to li sted species and their des ignate d critical habitat, the ecological problem formulation suppor ting thi s Final Work
5Plan for thiabendazo l e does not de scribe t he specific ESA analys i s, including effects 

### determinations for specific listed species or des ignated critical**habitat ~**  

### to be conducted during registration review. In the ecological problem formulation document for thiabendazole , EPA described the screening-level risk assessment to determine the potential effects of thiabendazole on all taxa of non-target wildlife and plants, which w iU assume that listed spec ies and their designated critical habitats may be present in the vic inity of th e app li cation of thiabendazole. This screening- lev el assessment wi ll a ll ow EPA to focus i ts future evaluatio ns on the types of species whe re the potential for effects exists once the scientific methods being developed by the agencies have been fully vetted. While the agenc ies continue to develop a common method for ESA analysis, the planned screeningle vel risk assessment fo r the registration review of thiabendazole will describe the level of ESA analysis completed for this particular registration review case. Once the agencies have fully develope d and implemented th e scientific methods necessary to complete ri sk assessments for endangered and threatened (listed) species and their designated critical habitats, these methods will be applied to subsequent analyses for thiabendazole as part of completing this registration review. 5. Comments submitted by Syngenta Crop Protection, LLC in EPA - HQ-OPP-2 014- 0715-0014. Comment: Two studies have been submitted in response to the requirement for Environmental Chemistry Methods (ECM) and Independent Laboratory Validation (IL V); Water. Note: Additional comments made by Syngenta are addressed in the Thiabendazole and Salts: Health Effects Division 's Response to Comments on the Thiabendazole Preliminary Work Plan (PWP) for Registration revi ew and the EFED Response to Comments on the Problem Formulation for Thiabendazole and Thiabendazole Hypochloride. Response: The Agency is in receipt of the two r eports submitted by Syngenta Crop Protection, LLC on May 28, 2014. These studies are currently being evaluated. 6. Comments submitted by Lanxess Corp oration via email. The comments submitted by Lanxess along with the Agency's response can be found in the Antimicrobial Division ' s Response to Public Comments on the Registration Review Preliminary Work Plan for Thiabendazole. Description of Other Changes to the List of Data Requirements from the PWP 1. As s tated in the problem formulation, EFED p lans on estimating toxicity us ing the acute-tochronic ratio method. Thus the requirement to conduct the life

-cycle study with the saltwater mysid (GLN 850.135) will not be included in the Generic Data Call-in (GDCI) for registration review. 2. As noted in the PWP, the developmental thyroid toxjcity will not be included in the 

### anticipated GDCI because it 

### is already required as a condition of registration.

63. The anticipated Special Study, Non-guideline for L each ing from treated textil es has been reclassified as guide line 875.2300 Indoor Surface Residue Dissipation, with specific use 

### sites. PLANNED DATA NEEDS Table 1 below summarizes the planned data needs for thiabendazole based on the Problem Formulation for the Ecological Risk and Drinking Water Exposure Assessments to be Conducted in Support of the Registration Review of Thiabendazole and its Hypophosphite Salt, and Thiabendazole and Salts: Human Health Risk Scoping Document in Support of Registration Review. The table has been updated since the PWP to reflect the data requirements that will be issued under the 

### DCI for regist ration review
. Tab l e 1: Planned Data Needs for the Thiabendazole Registration Review 

# I Estimated Guideline Study Title 2 Timeframe Number Test Material (Months from receipt ofDCI) 850
. 2100 Avian oral toxicity (passerine) TGAl 12 850.4500 Algal Toxicity T ier II

- marine diatom, freshwater TGAI 12 diatom, green algae 850.3300 Activated Sludge Respiration Inhib i tion (ASR1) 3 TGA I 12 835.3110 Ready Biodegradability or one of three 835.3220 835.3240 biodegradat i on in ac tivated sludge simulation TGAI 12 835.3280 tests 4 850.4550 Cyanobacteria toxicity TGAI 12

2 On June 27 , 2012, EPA announced certain revisions in harmonized guideline series 850

- Ecological Effects Tests

- including renumbering and other designations or changes for some guideline studies. See "Final Test Guidelines; OCSPP 850 Series; Notice of Availability " 77 FR 38282, June 27,2012. http: //www .regulations.gov /# !documentDetai I;D = E PA

- HQ

- OPPT

-2009-0 154

-0028 3 EPA has a published final guidance for this study: http :// www .regulations
. gov/# ! documentDetail ; D= EPA-HO

OPPT

- 2009

- 0 154-0021
. OECD Test Guide l ine 209 can also be used as guidance for th is study, availab l e online at htto: // www . oecd

- ilibrary
. org/content/book/9789264070080

- en . 4 The results of the Activated S ludge, Respiration Inhibition Test (ASRl), GLN 850.3300, will determine which of the four biodegredation tests is/are required. If the ASRI test resu lts in an ECsoofless than or equal to 20 mg/L, then the registrant is required to conduct either the (i) Simulation tests to assess the biodegradabi lity of chemicals discharged in wastewater 1
, GLN 835.3280 , (ii) the Simulation Test- Aerobic Sewage Treatment

- A
. Activated Sludge Units, GLN 835.3240, or (iii) the Porous Pot Test, GLN 835.3220. If.the ASRl test results in an ECso greater than 20 mg/L, then the registrant would be required to conduct either the (i) Ready Biodegradability, GLN 3110, (ii) Simulation tests to assess the biodegradability of chemicals discharged in wastewater , (iii) the Simulation TestAerobic Sewage Treatment

- A
. Activated Sludge Units, or (iv) the Porous Pot Test. Ifthe Ready Biodegradab i lity Study is conducted and passes, then no further testing is required. If, however, the pesticide fails the Ready Biodegradability study, then the registrant is required to conduct either the (i) Simulation tests to assess the biodegradability of chemicals discharged in wastewater , (ii) the Simulation Test

- Aerobic Sewage Treatment

- A
. Activated Sludge Units, or (iii) the Porous Pot Test. 7850.6100 E nv iro nm en tal c h e mis try methods and associated TGAJ 12 independent labo ratory validations for water 875
. 1 200 R es identi a l handler dermal exposure - indoor TEP 12 (ai rl ess spra ye r and brush/roll er) 875.1400 R es idential handler inhalati on exposure- TEP 24 indoor (air less spr a yer and brush/roller) 875.1 7 00 Product u se i n

formation T EP 12 875.2300 Ind oor surface residue dissipation (plush carpet TEP 24 and c lot hi ng) 5 875.2700 Product use data TEP 12 875.2800 Descriptions of human acti vity TEP 12 TGA I = techmcal grade act t ve mgredte nt; TEP = typtcal end-use product; RISK ASSESSMENTS FOR REGISTRATION REVIEW During regi stration review, the Agency wi ll conduct a co mpreh ensive eco logical risk assessment , including an endangered species assessment , for all uses of thiabendazole. Fo r hum an health , E PA anticipates th e need to conduct revised di etary , residential, and occup ational risk assessments during registration revi ew. If toxicological end points or points of departure are revised based o n the dat a that are anticipated to be required for regi st ration r ev iew, they will be co nsidered in th e new ass e ss me nts , as well as any c hanges to the s tandard operating proc e dur es or defaul t exposure a s sumptions
. Table 2 summarizes the planned registration review risk assessments based on t he EFED Pro blem Formul atio n and HED Scoping Document. The planned assessments have n ot c hanged fro m what was included in the PWP
.

5 Residue dissipation s tudie s are requ ir ed fortex'tiles ( clothi ng) and the plush of carp et s. If s pecified on the l abel that only carpet backing is treated, then a resi du e study wi ll not be needed for carpets. 

### 8Table 2: Planned Risk Assessments for th e Th iabendazole Registration Review 

### Type of Risk Assessment Conduct? Notes Ecolof.,-ical and Environmental Fate Co mpreh ensive ecolog ical y (species to be assessed in clude terrestrial and aquatic organis m s), including end angered specie s Incidents Will check for Base d on the low frequency and severity of incident updates cases reported for thiabendazo le and salts, there does not appear to be a concern at this time that would warrant further investigation. The Agency will continue to monitor the i ncid e nt in formation and if a concern is triggered , additiona l analysis will be included in the risk assessment. Human Health Di etary Food y A new dietary (food and water) risk assessment may need to be conducted i f there are changes to the thi abe ndazol e tox i co l ogical points of departure, safety factors or s i gnificant changes to t he estimated drinking water concentrations. Drinking water y The Agency will assess the need for a down-thedrai n assessment for the use of thiabendazole as a material preservative during the manufacturing process. O c cupational Handlers (mixe r s, loade r s, y Only the antimicrobial occupational handler appl icators) assessme n t will need to be revised. For conventional uses the occupational**exposur~** assessme nt s may need to be updated to refl ec t th e most recent occupa tional handler sur r ogate expos ure data as well as any s ignificant change in ex p osure assessment approaches. Post-application y For conventional uses t h e occupation al postapp lication exposure assessments may need to be updated to reflect the any significant change in expos ure assessm ent approaches. R esidential Hand lers y On l y the antimic robial residential handler assessment wi ll need to be conducted based on new handler exposure data for appl i cation of paints required for registration review.



### 9Post-application y Only th e a ntimicrobial post-appli cati on assessment \\ ill need t o be comp leted. This 

### "'ill incl ude treated clothing and carpet for dermal and**i~cidental** oral exposure. Other Cumulative N Thiabendazole has not been identified as a member of a cumulative group that shares a common mechanism of toxicity. Tolerances N Tolerances are estab li she d under 40 CFR § 180.242 for residues of thiabendazole , however a number of U.S. tolerances are not compatib l e with Canadian or CODEX MRL s. The tolerance residue defin i tion and leve l s will need to be exam ined during Registration Review to determine if compatibility can be achieved. Incidents Will check for Based on the low frequency and severity of incident updates cases reported for thiabendazole and salts, there does not appear to be a concern at this time that would warrant further investigation. The Agency will continue to monitor the incident information and if a concern is triggered , additional analysis will be included in the risk assessment. TIMELINE EPA has c reated the following estimated timeline for the comple tion of the thiabendazole registration review in Table 

### 3 below
. The projected tim e line has been updated to reflect minor delays in the publication of recent actions.

Table 3: Registration Review fo r Thiabendazole- Pro,jected Registration Review Timeline Activities Estimated Date Opening the Docket Open Docket and 60-day Public Comment Period March 2014

- Completed Close Public Comment Period May 2014

- Completed Case Develo pment Final Work Plan Sep. 2014

- Completed I ssue DCI 2014 Oct.- Dec
. Data Submiss ion 2016 Oct.- Dec. 60-day Public Comment Period for Draft Risk Assessments 6 2018 April

- June Registration Re view Deci sio n

6 The regu lat i ons govern ing Registration Review generally require the Agency to provide a public comment period of at"least 30 calendar days for draft risk assessments ; see 40 CFR Part l 55.53(c). For conventional pesticides , the Agency plans to provide a 60 calendar day public comment period ge nerally for dralt risk assessments. 10

### Table 3: Registration Review for Thia bendazole- Projected Registration Review Timeline Activities Estim ated Date 60 -d ay Public Comm ent Period for Prop osed Reg istrat ion R eview 2019 Jan- March D ecision Re gis tration Review Decisio n and Begi n Post-Decision Follo w-up 2019 Tota l (years) 5 

### NEXT STEPS A s no ted prev ious ly, the Agency plans to require several environmental fate , ecological effects, and human health studies for thiabendazole throug h a D a ta Ca ll-In Notice, expected to be issued in 20 14. ·

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