SERA TR 02-43-13-03b Triclopyr - Revised Human Health and Ecological Risk Assessments Final Report Prepared for: USDA, Forest Service Forest Health Protection GSA Contract No. GS-10F-0082F USDA Forest Service BPA: WO-01-3187-0150 USDA Purchase Order No.: 43-1387-2-0245 Task No. 13 Submitted to: Dave Thomas, COTR Forest Health Protection Staff USDA Forest Service Rosslyn Plaza Building C, Room 7129C 1601 North Kent Street Arlington, VA 22209 Submitted by: Patrick R. Durkin Syracuse Environmental Research Associates, Inc. 5100 Highbridge St., 42C Fayetteville, New York 13066-0950 Telephone: (315) 637-9560 Fax: (315) 637-0445 E-Mail: [email protected] Home Page: www.sera-inc.com March 15, 2003 TABLE OF CONTENTS LIST OF APPENDICES ...................................................... iv LIST OF WORKSHEETS ...................................................... v LIST OF ATTACHMENTS .................................................... v LIST OF TABLES ............................................................ v LIST OF FIGURES ......................................................... viii ACRONYMS, ABBREVIATIONS, AND SYMBOLS .............................. ix COMMON UNIT CONVERSIONS AND ABBREVIATIONS ......................... xi CONVERSION OF SCIENTIFIC NOTATION .................................... xii EXECUTIVE SUMMARY ................................................... xiii 1. INTRODUCTION ........................................................ 1-1 2. PROGRAM DESCRIPTION ................................................ 2-1 2.1. OVERVIEW ........................................................ 2-1 2.2. CHEMICAL DESCRIPTION AND COMMERCIAL FORMULATIONS ........ 2-1 2.3. APPLICATION METHODS ............................................ 2-2 2.4. USES AND APPLICATION RATES ..................................... 2-3 2.5. USE STATISTICS .................................................... 2-4 3. HUMAN HEALTH RISK ASSESSMENT ..................................... 3-1 3.1. HAZARD IDENTIFICATION ........................................... 3-1 3.1.1. Overview ................................................... 3-1 3.1.2. Mechanisms of Action ......................................... 3-1 3.1.3. Kinetics and Metabolism ....................................... 3-1 3.1.4. Acute Systemic Toxicity ....................................... 3-3 3.1.5. Subchronic and Chronic Systemic Toxicity ........................ 3-3 3.1.6. Effects on Nervous System ..................................... 3-5 3.1.7. Effects on Immune System ..................................... 3-5 ii TABLE OF CONTENTS (continued) 3.1.8. Effects on Endocrine Function ................................... 3-6 3.1.9. Reproductive and Teratogenic Effects ............................. 3-6 3.1.10. Carcinogenicity and Mutagenicity ................................ 3-8 3.1.11. Irritation and Sensitization ..................................... 3-10 3.1.12. Systemic Toxic Effects from Dermal Exposure .................... 3-10 3.1.13. Inhalation Exposure .......................................... 3-11 3.1.14. Adjuvants .................................................. 3-11 3.1.15. Impurities and Metabolites ..................................... 3-13 3.2. EXPOSURE ASSESSMENT ........................................... 3-14 3.2.1. Overview ................................................... 3-14 3.2.2. Workers .................................................... 3-14 3.2.3. General Public ............................................... 3-17 3.3. DOSE-RESPONSE ASSESSMENT .................................... 3-24 3.3.1. Overview ................................................... 3-24 3.3.2. Triclopyr ................................................... 3-24 3.3.3 TCP ....................................................... 3-26 3.4. RISK CHARACTERIZATION ........................................ 3-26 3.4.1. Overview ................................................... 3-26 3.4.2. Workers .................................................... 3-26 3.4.3. General Public ............................................... 3-28 3.4.4. TCP ....................................................... 3-30 4. ECOLOGICAL RISK ASSESSMENT ........................................ 4-1 4.1. HAZARD IDENTIFICATION ......................................... 4-1 4.1.1. Overview .................................................... 4-1 4.1.2. Toxicity to Terrestrial Organisms ................................. 4-1 4.1.2.1. Mammals ............................................ 4-1 4.1.2.2. Birds ................................................ 4-1 4.1.2.3. Invertebrates .......................................... 4-2 4.1.2.4. Soil Microorganisms ................................... 4-2 4.1.2.5. Terrestrial Plants ....................................... 4-2 4.1.2.6. Field Studies ......................................... 4-3 4.1.3. Aquatic Organisms ............................................ 4-4 4.1.3.1. Fish ................................................. 4-4 4.1.3.2. Amphibians .......................................... 4-5 4.1.3.3. Aquatic Invertebrates ................................... 4-6 4.1.3.5. Aquatic Plants ......................................... 4-6 4.1.3.6. TCP ................................................. 4-7 iii TABLE OF CONTENTS (continued) 4.2. EXPOSURE ASSESSMENT .......................................... 4-7 4.2.1. Overview .................................................... 4-7 4.2.2. Terrestrial Animals ............................................ 4-7 4.2.3. Terrestrial Plants ............................................. 4-12 4.2.4. Aquatic Organisms ........................................... 4-15 4.3. DOSE-RESPONSE ASSESSMENT .................................... 4-16 4.3.1. Overview ................................................... 4-16 4.3.2. Toxicity to Terrestrial Organisms ................................ 4-16 4.3.3. Aquatic Organisms ........................................... 4-19 4.4. RISK CHARACTERIZATION ........................................ 4-22 4.4.1. Overview ................................................... 4-22 4.4.2. Terrestrial Organisms ......................................... 4-22 4.4.3. Aquatic Organism ............................................ 4-24 5. REFERENCES .......................................................... 5-1 APPENDICES Appendix 1: Triclopyr Formulations with Forestry Applications (C&P Press 2002) Appendix 2: Forest Service Use of Triclopyr in 2001 (sorted by region) Appendix 3: Forest Service Use of Triclopyr in 2001 (sorted by use) Appendix 4: Acute toxicity of triclopyr and triclopyr formulations to experimental mammals Appendix 5: Systemic toxicity of triclopyr after repeated oral administrations Appendix 6: Developmental and Reproductive Effects Appendix 7: Mutagenicity studies on triclopyr Appendix 8: Repeated dermal dosing studies with triclopyr Appendix 9: Toxicity of triclopyr to birds Appendix 10: Toxicity of triclopyr to terrestrial plants Appendix 11: Field or field simulation studies Appendix 12: Toxicity of triclopyr to fish Appendix 13: Toxicity of triclopyr to aquatic invertebrates Appendix 14: Toxicity of triclopyr to aquatic plants Appendix 15: Toxicity of TCP to freshwater fish iv WORKSHEETS Supplement 1: Triclopyr Acid (Garlon 3A) - Worksheets for Human Health and Ecological Risk Assessments, SERA WPWS 01-43-15-01c (WordPerfect) and SERA EXWS 01-43-15-01c (EXCEL) dated February 18, 2003 Supplement 2: Triclopyr BEE (Garlon 4) -Worksheets for Human Health and Ecological Risk Assessments, SERA WPWS 01-43-15-02c (WordPerfect) and SERA EXWS 01-43-15-02c (EXCEL) dated February 18, 2003. ATTACHMENTS Attachment 1: Bibliography of Citations Encountered. Attachment 2: Documentation for Worksheets Version 2.04 - Human Health and Ecological Risk Assessments, SERA WSD 01-2.04 dated February 25, 2003. Attachment 3: Documentation for the Use of GLEAMS and Auxiliary Programs, SERA AT 2000-01d, dated October 12, 2001. LIST OF TABLES Table 2-1: Selected physical and chemical properties of triclopyr ..................... 2-9 Table 2-2: Selected physical and chemical properties of triclopyr BEE ................ 2-10 Table2-3: Use of triclopyr by USDA Forest Service in 2001 by Type of Use ........... 2-11 Table 2-4: Use of triclopyr by USDA Forest Service in 2001 by Region ............... 2-12 Table 3-1: Summary of studies on the reproductive effects of triclopyr acid, triclopyr TEA, and triclopyr BEE ................................................ 3-34 Table 3-2: Summary of worker exposure assessments .............................. 3-35 Table 3-3: Occupational exposure rates used in risk assessments ...................... 3-36 Table 3-4: Estimated absorption rates for workers involved in backpack applications of triclopyr BEE as Garlon 4 from the study by Middendorf (1992) ..... 3-37 Table 3-5: Estimated absorption rates for workers involved in backpack applications of triclopyr BEE as Garlon 4 from the study by Spencer et al. (2000) .... 3-38 Table 3-6: Summary of exposure assessments for the general public ................... 3-39 Table 3-7: Chemical specific parameters used in GLEAMS modeling and estimation of concentrations in ambient water ...................... 3-40 v LIST OF TABLES (continued) Table 3-8: Estimated concentrations of triclopyr in a small stream (4,420 m3/day) adjacent to a 10 acre plot based on GLEAMS modeling with different soil types and annual rainfall rates and using a normalized application rate of 1 lb/acre ....................................................