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Bioaccumulation Testing and Interpretation for the Purpose of Sediment Quality Assessment United States Office of Water (4305) EPA-823-R-00-001 Environmental Protection Office of Solid Waste (5307W) February 2000 Agency Bioaccumulation Testing And Interpretation For The Purpose Of Sediment Quality Assessment Status and Needs BIOACCUMULATION TESTING AND INTERPRETATION FOR THE PURPOSE OF SEDIMENT QUALITY ASSESSMENT STATUS AND NEEDS February 2000 U.S. Environmental Protection Agency Bioaccumulation Analysis Workgroup Washington, DC 20460 This document has been approved for publication by the U.S. Environmental Protection Agency. Mention of trade names or commercial products does not constitute endorsement or recommendation for use. This document describes existing knowledge on the use of bioaccumulation data as part of sediment quality assessments. It is not intended to serve as guidance or regulation. This document cannot impose legally binding requirements on EPA, States, Indian tribes, or the regulated community. i ii CONTENTS Acknowledgments ......................................................... vii Executive Summary ........................................................ ix Glossary ............................................................... xvii 1. Introduction ..............................................................1 1.1 Problem Statement .....................................................1 1.2 Purpose .............................................................1 1.3 Scope of the Document .................................................2 1.4 Regulatory Uses .......................................................2 1.5 Definitions ...........................................................5 1.6 References ...........................................................7 2. Factors Affecting Bioavailability ................................................9 2.1 Overview ............................................................9 2.2 Routes of Exposure ....................................................9 2.3 Physical Factors .......................................................9 2.4 Chemical Factors .....................................................10 2.5 Biological Factors ....................................................13 2.6 References ..........................................................14 3. Methods for Assessing Bioaccumulation .........................................19 3.1 Introduction .........................................................19 3.2 Laboratory and Field Methods for Assessing Bioaccumulation ....................21 3.2.1 Laboratory Determination of Bioaccumulation ..........................21 3.2.2 Field Determination of Bioaccumulation ...............................24 3.2.3 Statistical Design Considerations ....................................27 3.3 Approaches for Modeling Bioaccumulation ..................................28 3.3.1 Introduction ...................................................28 3.3.2 Empirical Models ...............................................29 3.3.3 Mechanistic Models .............................................35 3.4 Use of Critical Body Residue Approach ....................................39 3.5 Application of Approaches in Deriving Tissue Residue-linked Sediment Chemical Levels ...................................40 3.6 References ..........................................................43 4. Important Bioaccumulative Chemicals ...........................................51 4.1 Overview ...........................................................51 4.2 Rationale for Choice of Chemicals ........................................52 4.3 Summary Data in Tables ................................................56 4.4 Insights from Chemical Summary Tables ....................................58 4.5 References ..........................................................61 5. Summary of Agency Information on Bioaccumulation Data Collection and Interpretation ......65 5.1 EPA Headquarters Programs ............................................65 5.1.1 Office of Prevention, Pesticides and Toxic Substances (OPPTS) ............68 5.1.2 Office of Air and Radiation (OAR) ..................................72 iii CONTENTS (continued) 5.1.3 Office of Research and Development (ORD) ...........................73 5.1.4 Office of Solid Waste and Emergency Response (OSWER) ...............77 5.1.5 Office of Water (OW) ...........................................82 5.2 EPA Regions ........................................................91 Region 1 ...........................................................91 Region 2 ...........................................................92 Region 3 ...........................................................94 Region 5 ...........................................................95 Great Lakes National Program Office ......................................96 Region 6 ...........................................................97 Region 7 ...........................................................97 Region 9 ...........................................................97 Region 10 ..........................................................98 5.3 International Efforts ...................................................99 5.4 Summaries of Regional and Headquarters Activities ........................... 102 5.5 References ......................................................... 104 6. Issues and Research Needs for Interpreting Bioaccumulation Data for the Purpose of Sediment Quality Assessment ........................................................ 109 Appendix: Chemical-Specific Summary Tables (separate volume) iv TABLES 1. Summary of Uses of Bioaccumulation Data by Various EPA Programs for the Interpretation of Sediment Quality .......................................................... xiv 2-1. Summary of Factors Influencing Bioavailability of Sediment-associated Chemicals ..........10 4-1. Sources of Information for Selection of Important Bioaccumulative Compounds ............52 4-2. Important Bioaccumulative Compounds ..........................................53 5-1. Summary of EPA Uses of Bioaccumulation Data for the Interpretation of Sediment Quality ....66 FIGURE 3-1. Expected Proportion of Steady-state Concentration (Css) of Neutral Organic Compounds Reached in 28-Day Laboratory Exposures. .......................................25 v vi ACKNOWLEDGMENTS Valuable input or assistance was provided by the following EPA individuals: James Keating, Patti Tyler, Mindy Pensak, Tom Steeger, Jeneva Craig, Richard Healy, Robert Wood, Erik Winchester, Heidi Bell, Marjorie Wellman, William Tate, Kelly Eisenman, Kathy Davey, Jane Farris, Leanne Stahl, Rick Hoffmann, Bob Morcock, Keith Sappington, and Ted Dewitt. Technical support for completion of this document was provided under EPA contract #68-C98-111 by Tetra Tech, Inc. and their subcontractors EVS Environment Consultants, and SAIC. The Bioaccumulation Analysis Workgroup, co-chaired by OW/OST and OSWER/OSW, consists of 40 people from EPA headquarters, regional offices, and research laboratories with scientific and/or programmatic experience related to bioaccumulation testing and interpretation and sediment quality. Co-Chairs: Mike Kravitz OW/OST Stephen Kroner OSWER/OSW Members: Robert Boethling OPPTS/OPPT Robert Jones OPPTS/OPPT Ossi Meyn OPPTS/OPPT Jerry Smrchek OPPTS/OPPT Tom Bailey OPPTS/OPP Bryan Wood-Thomas OIA Brian Muehling OIA Steve Ells OSWER/OERR Mark Ralston OSWER/OSW Thomas Armitage OW/OST Jeffrey Bigler OW/OST William Morrow OW/OST Mary Reiley OW/OST David Redford OW/OWOW Sharon Lin OW/OWOW Clay Miller OW/OWOW Deborah Lebow OW/OWOW Laura Phillips OW/OWM Catherine Fox OECA (presently Region 4) Philip Cook ORD/NHEERL (Duluth) Michael Lewis ORD/NHEERL (Gulf Breeze) Richard Pruell ORD/NHEERL (Narragansett) Cynthia Nolt ORD/Headquarters Bruce Boese ORD/NHEERL (Corvallis) Marc Tuchman GLNPO David Tomey Region 1 Alex Lechich Region 2 Douglas Pabst Region 2 Charles Lobue Region 2 William Muir Region 3 Doug Johnson Region 4 Bonnie Eleder Region 5 vii John Dorkin Region 5 Amy Mucha Region 5 Philip Crocker Region 6 Monica Young Region 6 Gary Welker Region 7 Brian Ross Region 9 Erika Hoffman Region 10 Justine Barton Region 10 John Malek Region 10 viii EXECUTIVE SUMMARY Persistent bioaccumulative chemicals are distributed in sediments throughout the United States, with sediments serving as both a sink and a reservoir for these chemicals. As part of their sediment management decisions, the U.S. Environmental Protection Agency (EPA) and other regulatory agencies are frequently required to interpret the environmental significance from laboratory and field studies. Decisions that require the interpretation of bioaccumulation data are complicated by numerous factors, including variability in chemical bioavailability due to seasonal and physicochemical conditions. It is no longer sufficient to know only whether chemicals accumulate because bioaccumulation itself is not an effect but a process. Regulatory managers must know whether the accumulation of chemicals is associated with or responsible for adverse effects on the aquatic ecosystem and human health. Another complicating factor is that EPA programs have different mandates, often requiring different applications and uses of bioaccumulation data. EPA prepared this document to serve as a status and needs summary of the use of bioaccumulation data. The document is the result of a collaborative effort among the members of the EPA Bioaccumulation Analysis Workgroup. This document was also prepared to respond to increased interest in the fate
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