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

PC Code: 071503 DP Barcode: D421066, 422286 Date: September 17, 2014

MEMORANDUM

SUBJECT : Tier I Drinking Water Exposure Assessment in Support of the Proposed IR-4 New Use of Fludioxonil on Carrots and the Crop Group Conversion for Stone Fruit Group 12-12 and the Proposed Section 3 New Seed Treatment Use of Fludioxonil on Rapeseed Subgroup

20A

TO: Bill Wassell, Residue Chemist Billy Smith, Branch Chief

Risk Assessment Branch I Health Effects Division (7509P)

and AWillis Ertman, Risk Manager Reviewer Barbara Madden, Minor Use Team Leader Risk Integration, Minor Use, and Emergency Response Branch Registration Division (7505P)

and Erin Malone, Risk Manager Reviewer Shaja Joyner, Product Manager Fungicide Branch Registration Division (7505P)

FROM: Cheryl Sutton, Ph.D., Environmental Scientist

Environmental Risk Branch IV Environmental Fate and Effects Division (7507P)

REVIEWED Elyssa Arnold, Acting Risk Assessment Process Leader

BY: Environmental Risk Branch IV Environmental Fate and Effects Division (7507P)

APPROVED Sarah Winfield, Acting Branch Chief

BY: Environmental Risk Branch IV Environmental Fate and Effects Division (7507P)

The Environmental Fate and Effects Division (EFE D) has completed the Drinking Water Assessment (DWA) for the Interregional Research Project No. 4 (IR-4) Center for Minor Crop Pest Management’s minor use request for the post-harvest use of fl udioxonil (CAS No. 131341-86-1) on carrots, and for the crop group conversion for Stone Fr uit Group 12-12. This DWA also covers the proposed new seed

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 treatment use for Rapeseed Subgroup 20A. Product labels associated w ith this review are Maxim® 4FS (EPA Reg. No. 100-758) and Scholar SC (EPA Reg. No. 100-1242).

Fludioxonil post-harvest (dip/drench) use on carrots is proposed for the 

### control of white mold/sclerotinia rot. A DWA has previously been conducted for the IR-4 in-field use of fludioxonil on carrots (DP Barcodes: 285197, 285514, 286372, 286717; 1/2/2003) 1 

### . In that assessment, the registered application rate for carrots of four applications of 0.219 lb a.i./A at 7- to 10-day intervals for a maximum annual application of 0.88 lb a.i./A/yr is addressed. Estimated Drinking Water Concentrations (EDWCs) are not calculated for the carrot use in that assessment because the use rate is lower than previously assessed rates. The pro posed post-harvest use rate on carrots is as a dip containing 0.24 lb a.i./100 gallons.

Fludioxonil post-harvest use on stone fruits is proposed for the Stone Fruit Group 12-12 based on prior registration on multiple stone fruits for the control of various rots. The proposed post-harvestuse rate on stone fruits is as a dip containing 0.24 lb a.i./100 gallons or as an in-line aqueous or fruitcoating spray with a solution containing 0.24-0.48 lb a.i. (solution concentration not stated) per 200,000 pounds fruit.

Fludioxonil seed treatment is proposed for Rapeseed Subgroup 20A, expanding on the current seed treatment use on rapeseed and canola varieties, for protection against seed-borne and soil-borne fungi that cause decay, damping-off, and seedling blight. The proposed rate is 0.08-0.16 fl oz of product per 100 lb of seed (or 0.0025- 0.005 lb a.i./100 lb seed). At the maximum seeding rate of 8.2 lb rapeseed/A, the proposed maximum rate is 0.00041 lb a.i./A.

A new DWA was not conducted for the proposed ne w post-harvest uses stated above. Because EDWCs are based on the crop use with the maximum appli cation rate, the previously reported EDWCs for fludioxonil use on field grown ornamentals remain the recommended values for the human dietary assessment. These values are reported in Table 1 . Complete details on the determination of these values may be found in “ Tier I Drinking Water Assessment for the Fludioxonil Proposed Use on Ornamentals ” (DP Barcode: 364264; 6/22/2009) 2 and in a subsequent DWA for additional IR-4 uses (DP Barcodes 395364, 389616; 10/27/2011) 3 . It is noted that while EFED now has an additional model (PRZM-GW) available for the determination of EDWCs for groundwat er sources of drinking water, the contribution of groundwater relative to surface water EDWCs is neg ligible, and additional mo deling was not conducted.

1 USEPA, 2003. EFED Water Memorandum for the IR-4 Requests for the use of Fludioxonil (Switch 62.5 WG ® ) on Brassica, Carrot, Herb Subgroup 19A, and Lychee. Memorandum from John Ravenscroft, Jr., Environmental Fate and Effects Division, to Hoyt Jamerson and Shaja Brothers, Registration Division, dated January 2, 2003. DP Barcodes 285197, 285514, 286372, 286717. Office of Pes ticide Programs, U.S. Environmental Protection Agency.

2 USEPA, 2009. Tier I Drinking Water Assessment for the Fludioxonil Proposed Use on Ornamentals. Memorandum from Chuck Peck, Environmental Fate and Effects Division, to Mary Waller and Lisa Jones, Registration Division, dated June 22, 2009. DP Barcode 364264. Office of Pesticide Programs, U.S. Environmental Protection Agency.

3 Tier I Drinking Water Assessment in Support of Proposed or Amended Tolerances for the Fludioxonil IR-4 Uses on Ginseng; Onion Subgroup 3-07 A and B; Berry and Small Fruit Subgroups 13-07 A, B, F and G; Fruiting Vegetable Group 8-10, Except Tomato; Tomato; Leafy Vege table Except Brassica Subgroup 4A; Pome Fruit Group 11-10; Citrus Group 10-10; Potato; Pineapple; Dragon Fruit; Avocado; Mango; Other Various Tropical Fruits. Memorandum from Cheryl Sutton, Environmental Fate and Effects Division, to George Kramer and Dana Vogel, Health Effects Division, dated October 27, 2011. DP Barcodes 395364, 389616. Office of Pesticide Programs, U.S. Environmental Protection Agency.

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 Table 1. Maximum Tier I Estimated Drinking Wa ter Concentrations in surface water based on fludioxonil use on field grown ornamentals at 2 lb ai/A/yr.

DRINKING WATER SOURCE (MODEL USED) USE (rate modeled) MAXIMUM ESTIMATED DRINKING WATER CONCENTRATION (EDWC) ( μ g/L)

Groundwater (SCIGROW) Field grown ornamental (2 lbs. a.i./A/applic. x 1 applic.; total rate of 2 lb ai/A/yr ) Acute and Chronic 0.20

Surface Water (FIRST) Field grown ornamental (2 lbs. a.i./A/applic. x 1 applic.; total rate of 2 lb ai/A/yr ) Acute 83.8

Field grown ornamental (2 lbs. a.i./A/applic. x 1 applic.; total rate of 2 lb ai/A/yr ) Chronic 38.5