FINAL REPORT Approach for Assessing PFAS Risk to Threatened and Endangered Species SERDP Project ER18-1653 MARCH 2020 Craig Divine, Ph.D. Jean Zodrow, Ph.D. Meredith Frenchmeyer Katie Dally Erin Osborn, Ph.D. Paul Anderson, Ph.D. Arcadis US Inc. Distribution Statement A Page Intentionally Left Blank This report was prepared under contract to the Department of Defense Strategic Environmental Research and Development Program (SERDP). The publication of this report does not indicate endorsement by the Department of Defense, nor should the contents be construed as reflecting the official policy or position of the Department of Defense. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the Department of Defense. 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PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 2. REPORT TYPE 3. DATES COVERED (From - To) 03/31/2020 SERDP Final Report 6/15/2018 - 12/15/2019 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Approach for Assessing PFAS Risk to Threatened and Endangered Species 18-P-0048 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER Craig Divine, Ph.D. ER18-1653 Meredith Frenchmeyer 5e. TASK NUMBER Katie Dally Erin Osborn, Ph.D. Paul Anderson, Ph.D. 5f. WORK UNIT NUMBER Jean Zodrow, Ph.D. 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION Arcadis US Inc. REPORT NUMBER 630 Plaza Dr. Suite 100 ER18-1653 Highlands Ranch, CO 80129 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSOR/MONITOR'S ACRONYM(S) Strategic Environmental Research and Development Program SERDP 4800 Mark Center Drive, Suite 17D03 Alexandria, VA 22350-3605 11. SPONSOR/MONITOR'S REPORT NUMBER(S) ER18-1653 12. DISTRIBUTION/AVAILABILITY STATEMENT DISTRIBUTION STATEMENT A. Approved for public release: distribution unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT Per- and polyfluoroalkyl substances (PFAS) are a class of compounds with wide-ranging uses in industrial and commercial products and and processes. Use of aqueous film-forming foams represents a known and/or potential source of PFAS contamination at many DoD sites due to frequent use of these foams during maintenance activities and firetraining drills. The PFAS-containing aqueous film-forming foams were subsequently released directly to the ground or unlined pits. Additional sources of PFAS may also be present, as PFAS are used in a variety of applications (e.g., in certain paints, during chrome-plating, in photoprocessing) employed at DoD sites. The primary purpose of this evaluation is to develop risk-based screening levels (RBSL) protective of threatened and endangered species that are potentially present at DoD sites. Calculating RBSLs for aquatic life, terrestrial plants, soil invertebrates, and benthic invertebrates, requires acute and chronic toxicity data for individual PFAS. Calculating RBSLs for wildlife requires bioaccumulation factors and toxicity values for individual PFAS. Therefore, intermediate objectives of this evaluation include compiling appropriate toxicity and uptake data for individual PFAS and developing media and PFAS-specific bioaccumulation factors and toxicity values for wildlife. 15. SUBJECT TERMS PFAS, threatened, endangered, ecological, RBSL, screening level 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF 18. NUMBER 19a. NAME OF RESPONSIBLE PERSON ABSTRACT OF a. REPORT b. ABSTRACT c. THIS PAGE PAGES Craig Divine 19b. TELEPHONE NUMBER (Include area code) UNCLASS UNCLASS UNCLASS UNCLASS 341 714-508-2606 Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. Z39.18 Page Intentionally Left Blank TABLE OF CONTENTS Executive Summary ........................................................................................................................ 1 Abstract ........................................................................................................................................... 1 1 Objective ............................................................................................................................. 1 2 Background ......................................................................................................................... 1 3 Methods............................................................................................................................... 2 3.1 Aquatic Screening Levels ....................................................................................... 3 3.1.1 Aquatic Literature Review .......................................................................................3 3.1.2 Aquatic Screening Level Calculations .....................................................................5 3.2 Terrestrial Plant and Invertebrate Screening Levels ............................................... 9 3.2.1 Toxicity Value Literature Review ...........................................................................9 3.2.2 Soil Screening Level Development .......................................................................11 3.2.3 Sediment Screening Level Development ...............................................................11 3.3 Wildlife Risk-Based Screening Levels ................................................................. 11 3.3.1 Threatened and Endangered Species and Representative Surrogate Selection .....12 3.3.2 Development of Toxicity Reference Values ..........................................................13 3.3.3 Wildlife Risk-Based Screening Level Development .............................................18 4 Results ............................................................................................................................... 25 4.1 Aquatic Screening Levels ..................................................................................... 25 4.2 Screening Levels for Ecological Communities..................................................... 25 4.2.1 Plant and Soil Invertebrate Screening Levels ........................................................25 4.2.2 Benthic Invertebrate Screening Levels ..................................................................26 4.3 Wildlife Risk-Based Screening Levels ................................................................. 26 4.3.1 PFAS Risk-Based Screening Levels ......................................................................26 4.3.2 Considerations for Use of RBSLs ..........................................................................27 5 Uncertainties Evaluation ................................................................................................... 28 5.1 Uncertainties in the AQSLs (Tier II Methodology) .............................................. 29 5.1.1 Data Selection Uncertainties ..................................................................................29 5.1.2 Aquatic Screening Level Uncertainties .................................................................30 5.2 Terrestrial Plant and Invertebrate Screening Levels ............................................. 31 SERDP Per- and Polyfluoroalkyl Substances Ecological Risk-Based Screening Levels i March 2020 5.2.1 Data Selection Uncertainties ..................................................................................31 5.2.2 Plant and Invertebrate Soil Screening Levels Uncertainties ..................................32 5.3 Wildlife Risk-Based Screening Level Uncertainties ............................................ 32 5.3.1 Data Selection Uncertainties ..................................................................................32 5.3.2 Bioaccumulation Uncertainties ..............................................................................33 5.3.3 Toxicity Reference Value Uncertainties ................................................................35 5.3.4 Wildlife Risk-Based Screening Levels Uncertainties ............................................37 6 Discussion ......................................................................................................................... 38 7 Conclusions and Implications for Future Research .......................................................... 39 7.1 Conclusions ........................................................................................................... 39 7.2 Implications for Future Implementation ............................................................... 39 7.2.1 Applying SLs to Site Ecological Risk Assessments ..............................................40 7.3