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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 have 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 SUBSTANCES
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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 data 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 tetramethrin, 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 the esfenvalerate immunotoxicity study will be part 

of the registration review process. 

Comment #3: GLN 870.3465 – 90-day Inhalation Toxicity. 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-day inhalation toxicity study will be considered 

during the registration review process for esfenvalerate. 

Comment #4: GLN 870.6300 – Developmental Neurotoxicity (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 (corn, soybean, and sorghum aspirated grain 

fractions, cotton gin byproducts, pea (field) vines 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 concentration factor of 8.8x from treated sorghum 
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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 process 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 the 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.