2 INTRODUCTION

This is the Environmental Protection Agency’s (E PA or the Agency) Final Work Plan (FWP) for the registration review of dimethomorph. This work plan addresses public comments received concerning the Preliminary Work Plan (PWP), which was posted in the dimethomorph registration review docket (E PA-HQ-OPP-2013-0045). Dimethomor ph is a systemic morpholine fungicide developed to control dow ny mildews, late blights, and crown and root rots on grapes, potatoes, tomatoes, and other vegetables. Dime thomorph is also registered for use on various non-agricultural sites, such as fo rest trees and orname ntal plants, but there are no registered

residential uses.

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 scienc e, public policy, and pesticide us e practices occur over time. The registration review program is intended to make su re that, as the ability to assess risk evolves and as policies and practices change, al l registered pesticides continue to meet the statutory standard. The public phase of registration review begins wh en the initial docket is opened for each case. Information on this program is provided on the Agency’s website. 1

The FWP begins with any updates since the PWP wa s issued. Next is a summary of substantive comments received during the public comment peri od for the PWP concerning anticipated data needs, expected risk assessments, or the estimated timeline identified in the PWP, and a summary of the Agency’s responses to those comme nts. This section is followed by registration review planned data needs, risk assessments expected to be conducted, and the projected registration review timeline for dimethomorph. La stly, there is a discussion of next steps.

UPDATES SINCE TH E PWP WAS ISSUED

There are no additional updates on dimethomorph since the PWP.

SUMMARY OF COMMENTS AND AGENCY RESPONSES

During the 60-day public comment period on the Dimethomorph Preliminary Work Plan, which opened on March 27, 2013 and closed on May 2 8, 2013, the Agency received two public comments. Comments were submitted by BASF, the dimethomorph technical registrant, and by the FIFRA Endangered Species Task Force. The comments do not address the timeline described in the PWP, but they do address th e planned ecological and human health risk assessments and data requirements. In the PWP, EPA also solicited comments on the specific topics of environmental justice, water quality concerns , and trade irritants. No comments or information were received with regard to envi ronment justice or water quality concerns, but

BASF did comment on a tolerance issue which c ould result in a potential trade irritant.

This section does not capture every comment made about the PWP nor all of the Agency’s responses. Summarized below ar e public comments that resulted in changes to the anticipated

1 http://www.epa.gov/oppsrrd1/registration_review/3 registration review data needs, risk assessments, or timeline, or are of a broader regulatory nature. All public comments and the Agency’s response to comments documents can be found in the dimethomorph docket EPA-HQ-OPP-2013-0045.

Response to Public Comments by BASF C oncerning the Registration Review of Dimethomorph from EPA Docket ID No. EPA-HQ-OPP-2013-0045, DP Barcode #413157

. July 30, 2013. R. Prieto (Biological and Economic Anal ysis Division).

Response to Comments Received During the Dimethomorph Initial Registration Review Docket Opening 60-Day Public Comment Period . July 31, 2013. T. Gibson (Registration Division), S. Piper (Health Effects Divisi on), Monica Wait (Pesticide Re-evaluation Division).

Registration Review: EFED Response to Regi strant Comments on the Registration Review of Dimethomoph . July 30, 2013. S. Carey and I. Abde l-Saheb (Environmental Fate and Effects Division).

Comments submitted by BA SF in EPA-HQ-OPP-2013-0045-0010.

Comment: Based on previously submitted dimethomorph data and endpoints required for risk assessment, BASF proposes to conduct a freshwater fish acute toxicity study with the fathead minnow (GDLN 850.1075) in lieu of the fish early-life stage toxic ity study with the rainbow trout (GDLN 850.1400), which was listed as an anticipated data need in the PWP.

Response: The Agency agrees with BASF’s pr oposal that an acute study (GDLN 850.1075) with the fathead minnow, a freshwater fish, ra ther than an early lif e-stage study with the rainbow trout would be capable of producing the necessary endpoints to conduct an aquatic risk assessment. This endpoint from 850.1075 woul d then be compared with the available acceptable fathead minnow early-life study to deri ve an acute-to-chronic ratio (ACR) value in order to calculate toxicity endpoints for the aqua tic risk assessment. The Fish Early LifeStage study (GDLN 850.1400) with the rainbow trout that was requested in the dimethomorph PWP and preliminary problem form ulation is no longer re quired. A fish acute toxicity study with the fath ead minnow is now required.

Comment: BASF sought clarification as to whether the Agency is reques ting an environmental chemistry method (ECM) and independent laborat ory validation (ILV) for water only, or ECMs and ILVs for both water (GDLN 850.6100 ) and soil (GDLN 850.6100). Furthermore, BASF believes that the requireme nt for a soil ECM and ILV have been satisfied by a previous submission. Additionally, BASF noted that an ECM for the determination of dimethomorph in water is present and has been validated but that no ILV is cu rrently available.

Response: The Agency’s preliminary problem fo rmulation requested an ECM and ILV for both water and soil. In the Preliminary Wo rk Plan, only the ECM and ILV for water was listed individually in Table 1: Anticipated Data Needs . The ECM and ILV for soil was not listed in Table 1 because it is required as pa rt of GDLN 835.6100, terrestr ial field dissipation, under footnote 7 of the guideline. Since the fu ll terrestrial field diss ipation study was listed in Table 1, inclusive of the ECM and ILV for so il, there was no need to list it separately.4 Based on BASF’s comment and the submitted information in MRID 44996201, the request

for an ECM and ILV for the determination of dimethomorph in soil has been satisfied.

Regarding the data requirement for an ECM and ILV in water (GDLN 850.6100), BASF

stated that the ECM for water is available. As such, BASF should submit water ECM to the Agency. EPA confirms that the ILV for water continues to be required.

Comment : Regarding the data requirement for a te rrestrial field dissipation study (GDLN 835.6100), BASF states that they su bmitted four terrestrial fiel d dissipation studies to EPA on October 24, 2012 as a condition of registration as stated in an April 3, 2009 letter from the Office of Pesticide Program’s Registrati on Division. BASF suggests that these studies satisfy the condition of regi stration and therefore meet the 835.6100 guideline requirements.

Response: Previously submitted dimethomorph terr estrial field dissipation studies (MRIDs 48980101 thru 48980104) and the recently subm itted stability study (MRID 49126901) are currently in review. The data gap will remain until the reviews are completed and the studies are found to be acceptable.

Comment: A dimethomorph aerobic aquatic me tabolism study (MRID 43917233) found no major metabolites greater than 10% of the total applied radi oactivity, and based on that, BASF believes that the aquatic and drinking wa ter assessments should be based on parent dimethomorph only rather than parent dimet homorph plus a previously unidentified degradate.

Response: EPA concurs. The aquatic exposure and drinking water assessments will both be conducted for parent only.5 PLANNED DATA NEEDS

Table 1 below summarizes the planned data needs for dimethomorph based on the following

documents: Registration Review: Preliminary Problem Formulation for Environmental Fate and Ecological Risk, Endangered Species, and Drin king Water Assessments for Dimethomorph; Dimethomorph: Human Health Assessment Sc oping Document in Support of Registration

Review ; and the three response to comments documents cited in the previous section.

The table has been updated since the PWP to refl ect public comments which resulted in changes

to the data needs.

Table 1: Planned Data Needs for the Dimethomorph Registration Review

Guideline

Number 2 Study Title 2 Test Material Estimated

Timeframe

(Months from receipt of DCI)

835.6100 3 Terrestrial field dissipation study (full study) TEP 24

850.1075 Fish acute toxicity study (freshwater fish, fathead minnow) TGAI 12

850.2100 Avian oral toxicity (passerine species) TGAI 12

850.6100 Environmental chemistry methods and associated independent laboratory validation for water TGAI 12

TGAI = technical grade active ingredie nt; TEP = typical end-use product;

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 Av ailability” 77 FR 38282 , June 27, 2012. http://www.regulations.gov/#!documen tDetail;D=EPA-HQ-OPPT-2009-0154-0028

3 Previously submitted terrestrial field dissipation studies are currently in review. However, this data need will

remain until the reviews are completed and the studies are found to be acceptable.6 RISK ASSESSMENTS FOR REGISTRATION REVIEW

During registration review, the Agency will conduct a comprehensive ecological risk assessment, including an endangered species assessment, for all uses of di methomorph. For human health, EPA will conduct revised dietary and occupational risk assessments during registration review. If toxicological endpoints or points of departur e are revised based on the data that are required for registration review, they will be considered in the new assessments, as well as any changes to the standard operating procedures or default exposure assumptions.

Table 2 below summarizes the planned registrati on review risk assessments based on the EFED Problem Formulation and HED Scoping Document. The planned assessments have not changed

from what was included in the PWP.

Table 2: Planned Risk Asse ssments for the Dimethomorph Registration Review

Type of Risk Assessment Conduct? Notes

Ecological and Environmental Fate Comprehensive ecological (species to be assessed include terrestrial and aquatic organisms), including endangered species Y For terrestrial and aquatic exposures, risk calculations will be for the parent dimethomorph alone.

Incidents Will check for updates Currently, there are no repor ted ecological incidents for dimethomorph. For further information, see page

12 of the EFED Problem Formulation.

Human Health Dietary Food Y Only a chronic dietary exposure assessment is anticipated because no acute endpoint has been identified for dimethomorph. Drinking water Y The previous dr inking water assessment used a conservative Tier I approach and was conducted for the parent dimethomorph only. Occupational Handlers (mixers, loaders, applicators) Y The anticipated occupational assessment will be for inhalation exposures only because no dermal endpoint

was identified in available studies. Post-application Y

Residential Handlers N There are no registered residential uses. Post-application N

Other Aggregate N Because there are no residential exposures, an aggregate assessment, which evaluates the combined risk from dietary and residential exposures, is not

needed. Cumulative N Dimethomorph is not part of a cumulative group.7 Table 2: Planned Risk Asse ssments for the Dimethomorph Registration Review

Type of Risk Assessment Conduct? Notes

Tolerances Y Current tolerances , established in 40 CFR Part 180.493, will be evaluated during registration review.

Incidents Will check for updates At this time, there does no t appear to be a concern

that would warrant furt her investigation of dimethomorph human incidents. For a more detailed discussion, see Dimethomorph: Review of Human

Incidents in the docket or page 6 of the HED Scoping

Document.

TIMELINE

EPA has created the following estimated time line for the completion of the dimethomorph registration review in Table 3 be low. The projected timeline has been updated since the PWP to reflect impacts of recent Agency actions s hortening the timeframe between FWP and DCI issuance and adding a quarter in between posti ng of the preliminary risk assessments and proposed decisions.

Table 3: Projected Registration Review Timeline for Dimethomorph

Activities Estimated Date Opening the Docket Open Docket and 60-day Public Comment Period March 2013 – Completed

Close Public Comment May 2013 – Completed Case Development

Final Work Plan Sept. 2013 – Completed

Issue DCI 2014 – Jan. - March

Data Submission 2016 – Jan. - March 4
60-day Public Comment Period for Draft Risk Assessments 5 2017 – July - Sept. 4
Registration Review Decision 60-day Public Comment Period fo r Proposed Registration Review

Decision 2018 – Jan. - March 4

Registration Review Decision and Begin Post-Decision Follow-up 2019 4
Total (years) 6 4

4 If the terrestrial fi eld dissipation studies (GDLN 835.6 100) currently in review are found to be acceptable, the

timeline for data submission would be shortened from 24 months to 12 months. As such, the projected dates for data submission, draft risk assessments, proposed registration review decision, and post-decision follow-up would be moved up by one year. In that case, the total length of the registration review process for dimethomorph would be five years instead of six.

5 The regulations governing 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 155.53(c). For conventional pesticides, the Agency plans to provide a 60 calendar day public comment period generally for draft risk assessments.8 NEXT STEPS

As noted previously, the Agency plans to requ ire several environmenta l fate and ecological effects studies for dimethomorph through a Data Call- In Notice, expected to be issued in early2014.