SERA TR-052-27-03a Picloram Human Health and Ecological Risk Assessment Final Report Submitted to: Paul Mistretta, COR USDA/Forest Service, Southern Region 1720 Peachtree RD, NW Atlanta, Georgia 30309 USDA Forest Service Contract: AG-3187-C-06-0010 USDA Forest Order Number: AG-43ZP-D-10-0011 SERA Internal Task No. 52-27 Submitted by: Patrick R. Durkin Syracuse Environmental Research Associates, Inc. 8125 Solomon Seal Manlius, New York 13104 Fax: (315) 637-0445 E-Mail: [email protected] Home Page: www.sera-inc.com September 29, 2011 Table of Contents LIST OF TABLES ....................................................................................................................... viii LIST OF FIGURES ....................................................................................................................... ix LIST OF APPPENDICES ............................................................................................................. ix LIST OF ATTACHMENTS .......................................................................................................... ix ACRONYMS, ABBREVIATIONS, AND SYMBOLS ................................................................. x COMMON UNIT CONVERSIONS AND ABBREVIATIONS ................................................. xiii CONVERSION OF SCIENTIFIC NOTATION ......................................................................... xiv EXECUTIVE SUMMARY .......................................................................................................... xv 1. INTRODUCTION ...................................................................................................................... 1 1.1. Chemical Specific Information ............................................................................................ 1 1.2. General Information ............................................................................................................. 2 2. Program Description ................................................................................................................... 4 2.1 Overview ............................................................................................................................... 4 2.2. Chemical Description and Commercial Formulations ......................................................... 4 2.3. Application Methods ............................................................................................................ 6 2.4. Mixing and Application Rates ............................................................................................. 6 2.5. Use Statistics ........................................................................................................................ 7 3. HUMAN HEALTH .................................................................................................................... 9 3.1. HAZARD IDENTIFICATION .......................................................................................... 9 3.1.1. Overview ....................................................................................................................... 9 3.1.2. Mechanism of Action .................................................................................................. 10 3.1.3. Pharmacokinetics and Metabolism ............................................................................. 10 3.1.3.1. General Considerations ........................................................................................ 10 3.1.3.2. Dermal Absorption............................................................................................... 11 3.1.3.2.1. First-Order Dermal Absorption..................................................................... 12 3.1.3.2.2. Zero-Order Dermal Absorption .................................................................... 12 3.1.3.3. Excretion .............................................................................................................. 13 3.1.4. Acute Oral Toxicity .................................................................................................... 14 3.1.5. Subchronic or Chronic Systemic Toxic Effects .......................................................... 16 3.1.6. Effects on Nervous System ......................................................................................... 17 3.1.7. Effects on Immune System ......................................................................................... 18 3.1.8. Effects on Endocrine System ...................................................................................... 18 ii 3.1.9. Reproductive and Developmental Effects .................................................................. 19 3.1.9.1. Developmental Studies ........................................................................................ 19 3.1.9.2. Reproduction Studies ........................................................................................... 20 3.1.10. Carcinogenicity and Mutagenicity ............................................................................ 20 3.1.10.1. Picloram ............................................................................................................. 20 3.1.10.2. Hexachlorobenzene ............................................................................................ 21 3.1.11. Irritation and Sensitization (Effects on the Skin and Eyes) ...................................... 22 3.1.11.1. Skin Irritation ..................................................................................................... 22 3.1.11.2. Skin Sensitization............................................................................................... 22 3.1.11.3. Ocular Effects .................................................................................................... 22 3.1.12. Systemic Toxic Effects from Dermal Exposure ....................................................... 22 3.1.13. Inhalation Exposure .................................................................................................. 23 3.1.14. Adjuvants and Other Ingredients .............................................................................. 23 3.1.15. Impurities and Metabolites ....................................................................................... 24 3.1.15.1. Impurities ........................................................................................................... 24 3.1.15.2. Metabolites ......................................................................................................... 26 3.1.16. Toxicological Interactions ........................................................................................ 26 3.2. EXPOSURE ASSESSMENT .......................................................................................... 27 3.2.1. Overview ..................................................................................................................... 27 3.2.2. Workers ....................................................................................................................... 27 3.2.2.1. General Exposures ............................................................................................... 27 3.2.2.2. Accidental Exposures........................................................................................... 28 3.2.3. General Public ........................................................................................................... 30 3.2.3.1. General Considerations ........................................................................................ 30 3.2.3.1.1. Likelihood and Magnitude of Exposure ....................................................... 30 3.2.3.1.2. Summary of Assessments ............................................................................. 31 3.2.3.2. Direct Spray ......................................................................................................... 31 3.2.3.3. Dermal Exposure from Contaminated Vegetation ............................................... 32 3.2.3.4. Contaminated Water ............................................................................................ 32 3.2.3.4.1. Accidental Spill ............................................................................................. 32 3.2.3.4.2. Accidental Direct Spray/drift for a Pond or Stream ...................................... 33 3.2.3.4.3. GLEAMS Modeling...................................................................................... 34 3.2.3.4.3.1. Inputs to Gleams-Driver ........................................................................ 34 3.2.3.4.3.2. Output Gleams-Driver ........................................................................... 36 iii 3.2.3.4.3.2.1. Picloram .................................................................................................................................... 36 3.2.3.4.3.2.2. Hexachlorobenzene ................................................................................................................... 37 3.2.3.4.4. Other Modeling Efforts ................................................................................. 38 3.2.3.4.5. Monitoring Data ............................................................................................ 38 3.2.3.4.6. Concentrations in Water Used for Risk Assessment .................................... 39 3.2.3.5. Oral Exposure from Contaminated Fish .............................................................. 40 3.2.3.6. Dermal Exposure from Swimming