Page 1 of 3 UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON, D.C. 20460

MEMORANDUM

Date: 21-APR-2010

SUBJECT: Esfenvalerate. Response to Comments Received Regarding the HED Scoping Document Prepared in Support of Registration Review.

PC Code: 109303 DP Barcode: D375453

Decision No.: 409765 Registration No.: NA

Petition No.: NA Regulatory Action: Response to Comments Risk Assessment Type: NA Case No.: NA

TXR No.: NA CAS No.: 66230-04-4

MRID No.: NA 40 CFR: §180.533

Ver.Apr.08

FROM: William Donovan, Ph.D., Chemist Risk Assessment Branch V (RABV) Health Effects Division (7509P)

THRU: Jack Arthur, Branch Chief Risk Assessment Branch V (RABV) Health Effects Division (7509P)

TO: Molly Clayton/Michael Goodis, RM 53 Reregistration Branch 3 Pesticide Re-evaluation Division (7508P)

In response to the information contained in the esfenvalerate docket (EPA-HQ-OPP-2009-0301), MGK Company and DuPont Crop Protection ha ve submitted comments concerning the HED scoping document for esfenvalerate (D365049, W. Donovan et. al. , 01-DEC-2009). The present

memo addresses these comments.

MGK submitted the following comment in a letter dated 2/9/2010.

Comment #1: The human health risk assessment scoping document (pg. 10) summarizes the OFFICE OF PREVENTION, PESTICIDES, AND

TOXIC SUBSTANCESPage 2 of 3 indoor residential post-application exposure analysis. MGK would like to clarify that the assessment last conducted by EPA was a deterministic analysis of the indoor use scenarios little changed from the initial assessment conducted in 2004, and as such still contains little refinement of the exposure compared to real world use of esfenvalerate products. MGK highly encourages EPA to consider the deposition da ta provided (MRID 47547701) and the weight of the evidence arguments previously submitted regarding crack and crevice uses (MRID 47012901), a CARES model probabilistic risk assessment (MRID 47690501) as well as the cited Random Walk approach (MRID 47772701) in their next assessment for Registration Review. EPA accepted a number of probabilistic refinements to human health risk assessments for permethrin, allethrins, d-phenothrin and tetramet hrin, and we would like to encourage EPA to continue using the best available data and methods in future risk assessments.

HED Response: HED intends to update the residential exposure analysis for esfenvalerate making use of the best information available during the registration review process. A determination of the applicability of the studies cited by MGK Company will be made at that

time.

DuPont Crop Protection submitted the following comments in a letter dated 2/16/2010.

Comment #2: GLN 870.7800 – Immunotoxicity. An immunotoxicity study for esfenvalerate has

been initiated.

HED Response: Evaluation of the results of th e esfenvalerate immunotoxicity study will be part of the registration review process.

Comment #3: GLN 870.3465 – 90-day Inhalation Toxi city. A waiver request will be submitted for this study due to the physical chemical properties of the test substance. The waiver request should be submitted under separate cover on or about March 31, 2010.

HED Response: The waiver request for the 90-da y inhalation toxicity study will be considered during the registration review process for esfenvalerate.

Comment #4: GLN 870.6300 – Developmental Neurot oxicity (DNT). DuPont may choose to cite the six previously submitted DNT studies for pyrethroid pesticides to satisfy this data requirement.

HED Response: HED will proceed to evaluate the appropriate information once DuPont has determined how they would prefer to address this data requirement.

Comment #5: GLN 860.1500 – Crop Field Trials (c orn, soybean, and sorghum aspirated grain fractions, cotton gin byproducts, pea (field) vi nes and hay. The cotton gin byproduct and field pea trials have been completed and submitted to EPA under separate cover. Aspirated grain fraction data for sorghum demonstrates a con centration factor of 8.8x from treated sorghumPage 3 of 3 grain. Esfenvalerate residues in corn (0.02 ppm tolerance) and soybean grain (0.05 ppm tolerance) are much lower than those measured in sorghum grain (5 ppm tolerance). Accordingly, the sorghum results should be sufficient for setting tolerances for corn and soybean aspirated grain fractions.

HED Response: The cotton gin byproduct and field pea studies have been received and will be reviewed during the registration review proce ss for esfenvalerate. Although the higher residue levels in sorghum make it probable that this grain will form the basis of an aspirated grain tolerance for esfenvalerate, HED notes that large residue concentrations have been observed for soybean aspirated grain fractions with other active ingredients and this potential should not be discounted. Hence, DuPont should determine the residue concentration factor for esfenvalerate in aspirated grain fractions generated from treated soybean seed.

Comment #6: GLN 830.7050 – UV/Visible Light Absorption. This study (DuPont 16716) has been completed and was submitted to the Agency on 2/9/2010.

HED Response: Evaluation of the results of th e esfenvalerate UV/Vis study will be part of the registration review process.

Comment #7: Cabbage tolerance. The fenvalerate tolerances in 40 CFR 180.379 have been converted to esfenvalerate tolerances in 40 CFR 180.533 (74 FR Notice 46689-46699, September 11, 2009). During this process, the fenvalerate tolerance for cabbage (10.0 ppm) was converted to an esfenvalerate tolerance for “cabbage, except Chinese cabbage (3.0 ppm). The current Section 3 label for the esfenvalerate end use product, DuPont Asana XL Insecticide, has a registered use for “Chinese cabbage (tight headed varieties only, e.g. Napa cabbage)”. Therefore, DuPont requests that a correction be made to list an esfenvalerate tolerance of 3.0 ppm for “cabbage, Chinese, napa”.

HED Response: HED notes that according to 40 CFR 180.1(g), tolerances established for pesticides on cabbage also apply to Chinese cabbage (tight-headed varieties only). Because napa cabbage is considered a tight-headed variety, the cabbage tolerance should cover this commodity. Accordingly, HED recommends that the existing esfenvalerate tolerance for “cabbage, except Chinese cabbage” be changed to “cabbage” with the understanding that napa cabbage is part of the cabbage commodity definition. The current tolerance with regional registration listing under 180.533(c) for “cabbage, Chinese, bok choy” at 1.0 ppm is appropriate

and should be retained.