Page **1** of **2** UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, D.C. 20460 **OFFICE OF CHEMICAL SAFETY AND**  **POLLUTION PREVENTION MEMORANDUM**  **Date: February**  **23 , 2012**  **SUBJECT:** Quizalofop - P - ethyl: Amendment to the Human Health Risk Assessment and Summary of Analy tical Chemistry

and Residue Data for New Uses on Sorghum, Rapeseed Crop Group 20 A, and Field Corn **PC Code:** 128709 **DP Barcode:** D398731 **Decision No.:** 441518 and 443799 **Registration No. :**  352 - 541 and 352 - 542 **Petition No.:** 0E7802 and 1F7822 **Regulatory Action:** Tolerance Petition **Risk Assessment Type:** NA **Case No.:** NA **T XR No.:**  NA **CAS No.:** 100646 - 51 - 3 **MRID No.:** NA **40 CFR:** § 180.441 **FROM:** Ideliz Negrón - Encarnación, Ph.D., Risk Assessor

Risk Assessment Branch V Health Effects Division (7509P) Office of Pesticide Programs **THROUGH:** William Donovan, Ph.D., Chemist

Michael Metzger, Branch Chief Risk Assessment Branch V Health Effects Division (7509P) Office of Pesticide Programs **TO:** Laura Nollen, Risk Manager

Risk Management Division (RM 5; 7508 P) and Mindy Ondish, Risk Manager Risk Management Division (RM 25; 7508P)Page **2** of **2**

An amendment to the Human Health Risk Assessment (D384660 and D386678) and the S ummary of Analy tical and Residue D ata (D395630) for new uses of quizalofop - P - ethylwas required to address changes in the commodity definition of feedstuff commodities, grazing restrictions and adjuvant specifications. In addition, clarification on the decision for the storage stability studies of field corn was needed. The registrant is undergoing a storage stability study with field corn which will be further evaluated; however, storage stability was proven for wheat which is tentatively

used to cover that of the field corn samples. Based on this , HED understands that a conditional registration is not necessary for this case. 1. Tolerances for meal commodities RAB V recommended the creation of the rapeseed, subgroup 20A, meal, except flax, meal to propose tolerances for the meal commodities under the rapeseed, subgroup 20A, seed, except flaxseed. OPP further evaluated the proposal and considered that the registrant proposal was adequate for this case. In addition, the preferred commodity term for canola is rapeseed . Therefore, recommended commodity definitions and tolerances for the me al commodities are : gold of pleasure, meal 2.0 ppm

crambe, meal 2.0 ppm rapeseed, meal 2.0 ppm 2. Grazing restrictions The Section (3) label of Assure II (EPA Reg. No. 352 - 541) indicates that grazing of livestock is prohibited in treated areas. This restriction is not considered practical and should be removed . However, the grazing interval establish ed in the supplemental labels for use in field corn containing DAS - 40278 - 9 and sorghum containing the IN ZEN AII herbicide tolerant trait are considered appropriate because they match the PHIs established in the label . Therefore, the following directions s hould be kept in the supplemental labels.
 F ield corn containing DAS - 40278 - 9 : “Do not allow grazing on treated corn within 30 day s of application.”  S orghum containing the INZEN AII herbicide tolerant trait : “Do not graze livestock in treated areas or feed treated grain, forage, fodder, straw, or hay to livestock within 45 day s of Assure II application .” 3. Adjuvant specifications It was noted that the use of adjuvants established in the supplemental label for sorghum need to be modified to reflect the co nditions of the field trials. The adjuvant concentration was 1% (v/v) of the COC in all trials except one in which they used 0.25 % (v/v) of the NIS. The residue data onl y supports 1% of the COC or 0.25% of the NIS. Therefore, the label should be modifi ed accordingl y since in the draft label up to 2% COC and 0.5% NIS is recommended .