United States Environmental Office of Water EPA-822-R-05-006 Protection Agency Office of Science and December 2005 Technology 4304T Aquatic Life Ambient Water Quality Criteria Diazinon FINAL EPA-822-R-05-006 Aquatic Life Ambient Water Quality Criteria Diazinon (CAS Registry Number 333-41-5) FINAL December 2005 U.S. Environmental Protection Agency Office of Water Office of Science and Technology Washington, DC ii NOTICE This document has been reviewed in accordance with U.S. EPA policy and approved for publication. Mention of trade names or commercial products does not constitute endorsement or recommendation for use. This document can be downloaded from EPA’s website at: http://www.epa.gov/waterscience/criteria/aqlife.html iii FOREWORD Section 304(a)(1) of the Clean Water Act of 1977 (P.L. 95-217) requires the Administrator of the Environmental Protection Agency to publish water quality criteria that accurately reflect the latest scientific knowledge on the kind and extent of all identifiable effects on health and welfare which might be expected from the presence of pollutants in any body of water, including ground water. This document is a revision of proposed criteria based on consideration of comments received from independent peer reviewers and the public. Criteria contained in this document replace any previously published EPA aquatic life criteria for the same pollutant(s). The term “water quality criteria” is used in two sections of the Clean Water Act, section 304(a)(1) and section 303(c)(2). The term has a different program impact in each section. In section 304, the term represents a non-regulatory, scientific assessment of health or ecological effects. Criteria presented in this document are such scientific assessments. If water quality criteria associated with specific waterbody uses are adopted by a state or tribe as water quality standards under section 303, they become enforceable maximum acceptable pollutant concentrations in ambient waters within that state or tribe. Water quality criteria adopted in state or tribal water quality standards could have the same numerical values as criteria developed under section 304. However, in many situations states or tribes might want to adjust water quality criteria developed under section 304 to reflect local environmental conditions and exposure patterns. Alternatively, states or tribes may use different data and assumptions than EPA in deriving numeric criteria that are scientifically defensible and protective of designated uses. It is not until their adoption as part of state or tribal water quality standards that criteria become regulatory. Guidelines to assist the states and tribes in modifying the criteria presented in this document are contained in the Water Quality Standards Handbook (U.S. EPA 1994). The handbook and additional guidance on the development of water quality standards and other water-related programs of this agency have been developed by the Office of Water. This final document is guidance only. It does not establish or affect legal rights or obligations. It does not establish a binding norm and cannot be finally determinative of the issues addressed. Agency decisions in any particular situation will be made by applying the Clean Water Act and EPA regulations on the basis of specific facts presented and scientific information then available. Ephraim King, Director Office of Science and Technology iv ACKNOWLEDGMENTS Document Authors Larry T. Brooke University of Wisconsin-Superior Superior, WI Gregory J. Smith Great Lakes Environmental Center Columbus, OH U.S. EPA Document Coordinators Heidi Bell Office of Water Rick Stevens Office of Water U.S. EPA Technical Reviewers Tala Henry Office of Water Walter Berry Office of Research and Development Cindy Roberts Office of Research and Development Robert Spehar Office of Research and Development Thomas Steeger Office of Prevention, Pesticides and Toxic Substances Charles Stephan Office of Research and Development Glen Thursby Office of Research and Development v TABLE OF CONTENTS NOTICE........................................................................................................................................iii FOREWORD................................................................................................................................ iv ACKNOWLEDGMENTS ............................................................................................................ v FIGURES..................................................................................................................................... vii TABLES....................................................................................................................................... vii 1. INTRODUCTION.................................................................................................................1 1.1. Physical-Chemical Properties...................................................................................... 1 1.2. Diazinon in the Environment....................................................................................... 2 1.3. Toxicity of Diazinon...................................................................................................... 4 1.4. Derivation of Aquatic Life Ambient Water Quality Criteria ................................... 5 2. ACUTE TOXICITY TO AQUATIC ANIMALS............................................................... 6 2.1. Freshwater..................................................................................................................... 6 2.2. Saltwater ........................................................................................................................ 7 3. CHRONIC TOXICITY TO AQUATIC ANIMALS ......................................................... 9 3.1. Freshwater..................................................................................................................... 9 3.2. Saltwater ...................................................................................................................... 11 3.3. Acute-Chronic Ratios................................................................................................. 11 4. TOXICITY TO AQUATIC PLANTS............................................................................... 13 5. BIOACCUMULATION ..................................................................................................... 14 6. OTHER DATA.................................................................................................................... 15 6.1. Freshwater................................................................................................................... 15 6.2. Saltwater ...................................................................................................................... 20 6.3. Olfactory Effects of Diazinon in Aquatic Organisms .............................................. 21 7. UNUSED DATA.................................................................................................................. 23 8. SUMMARY ......................................................................................................................... 26 8.1. Freshwater Data.......................................................................................................... 26 8.2. Saltwater Data............................................................................................................. 26 8.3. Plant Data.................................................................................................................... 27 8.4. Bioaccumulation Data................................................................................................ 27 9. NATIONAL CRITERIA.................................................................................................... 28 9.1. Freshwater................................................................................................................... 28 9.2. Saltwater ...................................................................................................................... 28 10. IMPLEMENTATION .................................................................................................... 29 11. REFERENCES................................................................................................................ 60 vi FIGURES Page Figure 1. Summary of Ranked Diazinon GMAVs (Freshwater) ..................................................30 Figure 2. Summary of Ranked Diazinon GMAVs (Saltwater).....................................................31 Figure 3. Chronic Toxicity of Diazinon to Aquatic Animals .......................................................32 TABLES Table 1. Acute Toxicity of Diazinon to Aquatic Animals............................................................33 Table 2. Chronic Toxicity of Diazinon to Aquatic Animals.........................................................40 Table 3. Ranked Genus Mean Acute Values with Species Mean Acute-Chronic Ratios.............42 Table 4. Toxicity of Diazinon to Aquatic Plants ..........................................................................46 Table 5. Bioaccumulation of Diazinon by Aquatic Organisms ....................................................47 Table 6. Other Data on Effects of Diazinon on Aquatic Organisms ............................................48 vii 1. INTRODUCTION 1.1. Physical-Chemical Properties Diazinon [Chemical Abstract Service registry number 333-41-5; O,O-diethyl