United States Office of Water EPA 822-R-18-002 Environmental Protection 4304T April 2013 Agency AQUATIC LIFE AMBIENT WATER QUALITY CRITERIA FOR AMMONIA – FRESHWATER 2013 EPA-822-R-13-001 Aquatic Life Ambient Water Quality Criteria For Ammonia – Freshwater 2013 April 2013 U.S. Environmental Protection Agency Office of Water Office of Science and Technology Washington, DC ii TABLE OF CONTENTS TABLE OF CONTENTS ............................................................................................................... iii LIST OF TABLES ...........................................................................................................................v LIST OF FIGURES ....................................................................................................................... vi LIST OF APPENDICES ............................................................................................................... vii FOREWORD ............................................................................................................................... viii ACKNOWLEDGMENT................................................................................................................ ix EXECUTIVE SUMMARY .............................................................................................................x ACRONYMS ............................................................................................................................... xiii INTRODUCTION AND BACKGROUND ....................................................................................1 PROBLEM FORMULATION.........................................................................................................4 Overview of Stressor Sources and Occurrence ........................................................................... 5 Environmental Fate and Transport of Ammonia in the Aquatic Environment ........................... 6 Mode of Action and Toxicity ...................................................................................................... 8 Assessment Endpoints ................................................................................................................ 9 Measures of Effect .................................................................................................................... 10 Acute measures of effect ....................................................................................................... 11 Chronic measures of effect ................................................................................................... 12 Chronic averaging period of 30 days .................................................................................... 13 Ammonia toxicity data fulfilling minimum data requirements ............................................ 14 Conceptual Model ..................................................................................................................... 16 Conceptual diagram .............................................................................................................. 17 Analysis Plan ............................................................................................................................ 19 EFFECTS ANALYSES FOR FRESHWATER AQUATIC ORGANISMS .................................21 Acute Toxicity to Aquatic Animals .......................................................................................... 21 Summaries of studies used in acute criterion determination................................................. 24 Chronic Toxicity to Freshwater Aquatic Animals .................................................................... 31 Summaries of studies used in chronic criterion determination ............................................. 34 The National Criteria for Ammonia in Fresh Water ................................................................. 40 Acute criterion calculations .................................................................................................. 40 Chronic criterion calculations ............................................................................................... 46 Additional explanation and justification supporting the 2013 temperature and pH-dependent calculations and criteria magnitudes ..................................................................................... 50 Protection of downstream waters .......................................................................................... 51 Considerations for site-specific criteria derivation ............................................................... 52 EFFECTS CHARACTERIZATION .............................................................................................52 Freshwater Acute Toxicity Data ............................................................................................... 53 Acute toxicity data for freshwater mussels and non-pulmonate (gill-bearing) snails........... 53 Freshwater Chronic Toxicity Data ............................................................................................ 56 Use of 28-day juvenile unionid mussel data ......................................................................... 56 28-day toxicity data for freshwater snails ............................................................................. 56 iii 28-day toxicity data for Hyalella azteca: Minimum Data Requirement Number 5 .............. 57 Reconsideration of the chronic toxicity data available for aquatic insects: Minimum Data Requirement Number 6 ......................................................................................................... 59 New chronic toxicity data for salmonid species and derivation of a GMCV for Oncorhynchus: Minimum Data Requirement Number 1 ...................................................... 59 Another order of insect or a phylum not already represented: Minimum Data Requirement Number 8 .............................................................................................................................. 61 Protection of Endangered Species ............................................................................................ 62 Key acute toxicity data for listed species .............................................................................. 62 Key chronic toxicity data for listed species .......................................................................... 64 Comparison of 1999, 2009, and 2013 Criteria Values ............................................................. 65 Comparison of statistical approaches to develop the chronic criterion: EC20 vs. MATC ... 68 UNUSED DATA ...........................................................................................................................68 REFERENCES ..............................................................................................................................70 iv LIST OF TABLES Table 1. Summary of Assessment Endpoints and Measures of Effect Used in Criteria Derivation for Ammonia. ...................................................................................................13 Table 2. 1985 Guidelines Minimum Data Requirements Summary Table Reflecting the Number of Species and Genus Level Mean Values Represented in the Acute and Chronic Toxicity Datasets for Ammonia in Freshwater. ...................................................15 Table 3. Ranked Genus Mean Acute Values. ...............................................................................27 Table 4. Ranked Genus Mean Chronic Values. ............................................................................39 Table 5a. Temperature and pH-Dependent Values of the CMC (Acute Criterion Magnitude) – Oncorhynchus spp. Present. ............................................................................................44 Table 5b. Temperature and pH-Dependent Values of the CMC (Acute Criterion Magnitude) – Oncorhynchus spp. Absent. ............................................................................................45 Table 6. Temperature and pH-Dependent Values of the CCC (Chronic Criterion Magnitude). ........................................................................................................................49 Table 7. Comparison of the Four Taxa Used to Calculate the FAV and CMC in the 1999, 2009 Draft and 2013 AWQC. ............................................................................................55 Table 8. Comparison of the Four Taxa Used to Calculate the FCV and CCC in the 1999 Update, 2009 Draft and the 2013 AWQC. .........................................................................67 Table F.1. Species, Genus and Taxon-Specific ACRs for Freshwater Aquatic Animals Exposed to Ammonia .......................................................................................................145 Table M.1. Results of Regression Analysis of logLC50 (mg/L total ammonia nitrogen) Versus Temperature (°C) for Individual Data Sets on the Temperature Dependence of Acute Ammonia Toxicity. ...........................................................................................215 Table M.2. Results of Regression Analysis of log LC50 (mg/L total ammonia nitrogen) Versus Temperature (°C) for Pooled Data Sets on the Temperature Dependence of Acute Ammonia Toxicity to Fish. ...................................................................................216 Table N.1. Temperature and pH-Dependent Values of the CMC (Acute Criterion Magnitude) – Unionid Mussels