United States Prevention, Pesticides EPA 738-R-04-012 Environmental Protection and Toxic Substances July 2004 Agency (7508C) Reregistration Eligibility Decision for Benfluralin CERTIFIED MAIL Dear Registrant: This is to inform you that the Environmental Protection Agency (hereafter referred to as EPA or the Agency) has completed its review of the available data and public comments received related to the risk assessment for the dinitroaniline pesticide, benfluralin (Balan®). Based on its review, EPA has identified risk mitigation measures that the Agency believes are necessary to address the human health and environmental risks associated with the current use of benfluralin. The EPA is now publishing its reregistration eligibility and risk management decisions for the current uses of benfluralin, and its associated human health and environmental risks. The enclosed “Reregistration Eligibility Decision for Benfluralin,” which was approved on July 30, 2004, contains the Agency’s decision on the individual chemical benfluralin. A Notice of Availability for this Reregistration Eligibility Decision (RED) for benfluralin is published in the Federal Register. To obtain a copy of the RED document, please contact the OPP Public Regulatory Docket (7502C), US EPA, Ariel Rios Building, 1200 Pennsylvania Avenue NW, Washington, DC 20460, telephone (703) 305-5805. Electronic copies of the RED and all supporting documents are available on the Internet. See http://www.epa.gov/pesticides/reregistration/status.htm. This document and the process used to develop it are the result of EPA’s program to facilitate greater public involvement and participation in the Agency’s pesticide reregistration and tolerance reassessment decision making. Since the enactment of the Food Quality Protection Act of 1996 (FQPA), EPA has undertaken special efforts to increase transparency, consult with stakeholders, and engage the public in developing pesticide reregistration and tolerance reassessment decisions. The human health and environmental risk assessments for benfluralin were placed in the public docket and issued for public comment through a Federal Register notice on February 25, 2004. At this time, the Agency does not have sufficient data concerning common mechanism issues to determine whether or not benfluralin shares a common mechanism of toxicity with other substances, including other dinitroaniline or other pesticides. Therefore, for the purposes of this action, the Agency has assumed that benfluralin does not share a common mechanism of toxicity with any other chemicals. End-use product labels should be revised by the manufacturer to adopt the changes set forth in Section V of this document. Instructions for registrants on submitting revised labeling and the time frame established to do so can be found in Section V of this document. If you have questions on this document or the proposed label changes, please contact the Special Review and Reregistration Division representative, Katie Hall, at (703) 308-0166. For questions about product reregistration and/or the Product data call-in (DCI) that accompanies this document, please contact Moana Appleyard at (703) 308-8175. Debra Edwards, Ph.D. Director, Special Review and Reregistration Division Attachment Reregistration Eligibility Decision for Benfluralin List B Case 2030 Approved By: ______________________ Debra Edwards, Ph.D. Director, Special Review and Reregistration Division ______________________ Date Table of Contents Glossary of Terms and Abbreviations............................................... i Benfluralin Reregistration Eligibility Decision Team ................................... iii Executive Summary ............................................................ 1 I. Introduction ............................................................. 6 II. Chemical Overview....................................................... 8 A. Regulatory History ................................................. 8 B. Chemical Identification.............................................. 8 C. Use Profile ....................................................... 9 D. Estimated Usage of Pesticide......................................... 10 III. Summary of Benfluralin Risk Assessments .................................... 11 A. Human Health Risk Assessment...................................... 11 1. Dietary Risk from Food....................................... 11 a. Toxicity of Benfluralin ................................. 11 b. FQPA Safety Factor ................................... 15 c. Population Adjusted Dose ............................... 15 1) Acute PAD.................................... 16 2) Chronic PAD .................................. 16 d. Exposure Assumptions ................................. 16 e. Dietary (Food) Risk Assessment .......................... 16 1) Acute Dietary Risk.............................. 16 2) Chronic (Noncancer) Dietary Risk .................. 16 2. Dietary Risk from Drinking Water .............................. 17 a. Surface Water ........................................ 17 b. Ground Water ........................................ 18 3. Residential and Other Nonoccupational Exposure ................... 18 a. Residential Applicator (Handler).......................... 19 1) Exposure, Scenarios, Data, and Assumptions .......... 19 2) Benfluralin Residential Handler Risk Estimates......... 19 b. Residential Postapplication Risk.......................... 21 1) Exposure, Scenarios, Data, and Assumptions .......... 21 2) Benfluralin Postapplication Risk Estimates............ 22 4. Aggregate Risk............................................. 23 a. Short-term Aggregate Risk.............................. 23 b. Chronic Aggregate Risk ................................ 24 5. Cumulative Assessment ...................................... 24 6. Occupational Risk........................................... 25 a. Occupational Toxicity.................................. 25 b. Occupational Handler Exposure .......................... 26 c. Occupational Handler Risk Summary...................... 26 d. Occupational Postapplication Risk Summary for Benfluralin.....31 e. Human Incident Data .................................. 31 B. Environmental Risk Assessment...................................... 32 1. Environmental Fate and Transport............................... 32 2. Ecological Risk............................................. 33 a. Risk to Birds......................................... 34 1) Toxicity (Hazard) Assessment ...................... 34 2) Exposure and Risk .............................. 35 b. Risk to Mammals ..................................... 37 1) Toxicity (Hazard) Assessment ...................... 37 2) Exposure and Risk .............................. 37 c. Risk to Fish and Aquatic Invertebrates .....................38 1) Toxicity (Hazard) Assessment for Freshwater Species ....38 2) Toxicity (Hazard) Assessment for Estuarine/Marine Species ............................................. 40 3) Exposure and Risk .............................. 40 d. Risk to Nontarget Insects................................ 45 e. Risk to Nontarget Terrestrial Plants........................ 45 f. Risk to Nontarget Aquatic Plants.......................... 48 g. Food-Chain Effects .................................... 48 h. Risk to Endangered Species ............................. 49 i. Ecological Incident Reports.............................. 50 IV. Risk Management, Reregistration, and Tolerance Reassessment Decision.............51 A. Determination of Reregistration Eligibility .............................. 51 B. Public Comments and Responses ..................................... 51 C. Regulatory Position ................................................ 51 1. Food Quality Protection Act Findings ............................ 52 a. “Risk Cup” Determination .............................. 52 b. Determination of Safety to U.S. Population ..................52 c. Determination of Safety to Infants and Children ..............52 d. Endocrine Disruptor Effects ............................. 53 e. Cumulative Risks ..................................... 53 2. Tolerance Summary ......................................... 54 a. Tolerances Currently Listed Under 40 CFR §180.208 ..........54 b. Codex Harmonization.................................. 55 c. Residue Analytical Methods - Plants and Livestock ............55 D. Regulatory Rationale............................................... 55 1. Human Health Risk Management............................... 56 a. Dietary (Food) Risk Mitigation ........................... 56 b. Drinking Water Risk Mitigation .......................... 56 c. Residential Risk Mitigation .............................. 56 d. Aggregate Risk Mitigation .............................. 57 1) Acute Aggregate Risk............................ 57 2) Short-term Aggregate Risk........................ 57 3) Chronic (Non-Cancer) Aggregate Risk............... 57 e. Occupational Risk Mitigation ............................ 57 1) Handler Exposure ............................... 57 2) Post-application Risk Mitigation .................... 57 2. Environmental Risk Mitigation ................................. 57 3. Other Labeling Requirements.................................. 64 4. Endangered Species Considerations ............................. 65 5. Spray Drift Management...................................... 65 A. Manufacturing Use Products ......................................... 67 1. Additional Generic Data Requirements..........................