Water-Quality Benchmarks for Pesticides

by Lisa Nowell

This guidance provides sources of current (September 2008) standards and guidelines for pesticides in water, bed sediment, and fish tissues. Standards and guidelines can be used as benchmarks for comparison with measured pesticide concentrations in applicable media to help assess the potential effects of pesticides on water quality in the hydrologic systems being studied. This guidance emphasizes national standards and guidelines established for freshwater systems in the United States or Canada. Selected regional and State guidelines also are included for sampling media and beneficial uses for which national guidelines are limited (for example, whole-fish guidelines for protection of wildlife).

The following terms are used in this guidance:

Standard: threshold values that are legally enforceable by agencies of the U.S. Government
Guideline: threshold values that have no regulatory status but are issued in an advisory capacity
Benchmark: generic term for a threshold value against which measured concentrations can be compared; it encompasses both standards and guidelines

Each type of benchmark applies to a specific sampling medium (drinking water, ambient surface water, bed sediment, whole fish, or edible fish tissue) and is designed to protect a specific beneficial use of the hydrologic system (human health, aquatic life, or wildlife). In selecting the appropriate benchmarks to use in comparison with water-quality data, consider both sampling medium and the beneficial uses of the hydrologic system being studied. More than one type of benchmark may be appropriate for some hydrologic systems (such as surface water that is used for drinking water and that also supports aquatic life).

The USGS National Water-Quality Assessment (NAWQA) Program used several of the benchmarks listed below in its national-scale analysis of pesticide concentrations measured in U.S. streams and ground water during the first ten years of the Program (1992 to 2001), as described in USGS Circular 1291. The actual benchmark values (which were current as of December 2005) used in that analysis are available in the online Appendix 3 of Circular 1291. However, the values available for a given type of benchmark may change over time. Therefore, for up-to-date benchmark values, users are directed to the original sources for each benchmark type (see links in the list below). The types of benchmarks used by the NAWQA Program to assess potential effects of measured pesticide concentrations on human health, aquatic life, or fish-eating wildlife are indicated with a double asterisk (**) in the list below.

The effective use of benchmarks in water-quality assessment requires an understanding of how individual benchmarks were derived, as well as information about the specific hydrologic system being studied. Therefore, users are encouraged to consult these sources, not just for benchmark values, but also for information on the technical bases and underlying assumptions of these benchmarks.

Benchmark sources below are listed by sampling medium, as follows:

I. WATER COLUMN


II. BED SEDIMENT

III. FISH AND SHELLFISH TISSUE

BENCHMARK SOURCES

I. WATER COLUMN

A. DRINKING WATER

1. EPA Drinking Water Standards and Health Advisories **

   Sampling medium:	Drinking water
   Resource protected:	Human health
   Internet sources:	Drinking Water Regulations and Health Advisories Print Version (2006)

2. USGS Health-Based Screening Levels **

   Sampling medium:	Drinking water
   Resource protected:	Human health
   Internet source:	Health-Based Screening Levels: A Tool for Evaluating What Water-Quality Data May Mean to Human Health (2008)

3. Canadian Guidelines for Drinking Water Quality

   Sampling medium:	Drinking water
   Resource protected:	Human health
   Internet source:	Guidelines for Canadian Drinking Water Quality, Summary Table (May 2008)

4. NAS Drinking Water and Health Recommendations

   Sampling medium:	Drinking water
   Resource protected:	Human health
   Source:	References (1977 - 1989)
   Internet source:	Available from National Academy Press

B. AMBIENT SURFACE WATER

1. EPA Ambient Water-Quality Criteria for the Protection of Human Health

   Sampling medium:	Ambient surface water
   Resource protected:	Human health
   Internet sources:	Current National Recommended Water Quality Criteria Print version (2006)

2. EPA Ambient Water-quality Criteria for the Protection of Aquatic Organisms **
   

   Sampling medium:	Ambient surface water
   Resource protected:	Aquatic life
   Internet sources:	Current National Recommended Water Quality Criteria Print version (2006)

3. Aquatic Life Benchmarks Developed Cooperatively by the USGS and EPA **

   Sampling medium:	Ambient surface water
   Resource protected:	Aquatic life
   Internet source:	Technical Overview of Ecological Risk Assessment Aquatic Life, Benchmark Table (March 2008)

4. Canadian Water Quality Guidelines for Aquatic Life

   Sampling medium:	Ambient surface water
   Resource protected:	Aquatic life
   Internet sources:	Canadian Water Quality Guidelines Summary Tables of Canadian Environmental Quality Guidelines Canadian Water Quality Guidelines for the Protection of Aquatic Life - Summary Table (Chapter 4) (Update 7.1, December 2007)

5. Great Lakes Water Quality Objectives

   Sampling medium:	Ambient surface water
   Resource protected:	Aquatic life
   Internet sources:	Specific Objectives Great Lakes Water Quality Agreement of 1978, as amended by Protocol signed November 18, 1987

6. NAS/NAE Recommended Maximum Concentrations in Water

   Sampling medium:	Ambient surface water
   Resource protected:	Aquatic life
   Source:	Reference (1973)
   Internet source:	Available from National Technical Information Service (NTIS No. PB-236 199)

II. BED SEDIMENT

1. EPA Equilibrium Partitioning Sediment Benchmarks

   Sampling medium:	Bed sediment
   Resource protected:	Aquatic life
   Internet sources:	2004 Contaminated Sediment Report to Congress: The Incidence and Severity of Sediment Contamination in Surface Waters of the United States: National Sediment Quality Survey, Second Edition (see especially Appendix C, Values Used for Chemicals Evaluated) The complete report (PDF) Procedures for the Derivation of Equilibrium Partitioning Sediment Benchmarks (ESBs) for the Protection of Benthic Organisms: Dieldrin Endrin Sediment Quality Guidelines EPA listing of EPA publications and related links fom other agencies and organizations

2. Canadian Interim Sediment Quality Guidelines

   Sampling medium:	Bed Sediment
   Resource protected:	Aquatic Life
   Internet sources:	Summary Tables of Canadian Environmental Quality Guidelines Canadian Sediment Quality Guidelines Summary Tables--Canadian Sediment Quality Guidelines for the Protection of Aquatic Life (Update 2002)

3. Consensus-Based Sediment Quality Guidelines **

   Sampling medium:	Drinking water
   Resource protected:	Human health
   Source:	Reference (2000)
   Internet source:	Prediction of Sediment Toxicity Using Consensus-based Freshwater Sediment Guidelines

III. FISH AND SHELLFISH TISSUE

A. EDIBLE FISH AND SHELLFISH TISSUE

1. EPA Tolerances

   Sampling medium:	Edible fish and shellfish
   Resource protected:	Human health
   Internet sources:	What the Pesticide Residue Limits are on Food Code of Federal Regulations, 40 CFR Part 180

2. FDA Action Levels

   Sampling medium:	Edible fish and shellfish
   Resource protected:	Human health
   Internet source:	Compliance Policy Guide, Sec. 575.100 Pesticide Residues in Food and Feed - Enforcement Criteria (CPG 7141.01)

3. EPA Recommended Screening Values

   Sampling medium:	Edible fish and shellfish
   Resource protected:	Human health
   Internet sources:	Guidance for Assessing Chemical Contaminant Data for Use in Fish Advisories, Vol. 1, 3rd ed., Fish Sampling and Analysis (November 2000) See especially Ch. 5 which includes Table 5-3 (Dose-response variables and recommended screening values for target analytes - Recreational fishers) and Table 5-4 (Dose-response variables and recommended screening values for target analytes - Subsistence fishers)

4. Great Lakes Water Quality Objectives

   Sampling medium:	Edible fish
   Resource protected:	Human health
   Internet sources:	Specific Objectives Great Lakes Water Quality Agreement of 1978, as amended by Protocol signed November 18, 1987

B. WHOLE FISH

1. Canadian Tissue Residue Guidelines for the Protection of Wildlife Consumers of Aquatic Biota

   Sampling medium:	Whole fish
   Resource protected:	Fish-eating wildlife
   Internet sources:	Summary Tables of Canadian Environmental Quality Guidelines Canadian Tissue Residue Guidelines Summary Table--Canadian Tissue Residue Guidelines for the Protection of Wildlife Consumers of Aquatic Biota (Update 2001)

2. New York Fish Flesh Criteria for Piscivorous Wildlife
   

   Sampling medium:	Whole fish
   Resource protected:	Fish-eating wildlife
   Internet source:	New York State Department of Environmental Conservation (1987; reprinted February 2000)

3. NAS/NAE Recommended Maximum Tissue Concentrations

   Sampling medium:	Whole fish
   Resource protected:	Fish-eating wildlife
   Source:	Reference

4. Great Lakes Water Quality Objectives

   Sampling medium:	Whole fish
   Resource protected:	Fish-eating wildlife
   Internet sources:	Specific Objectives Great Lakes Water Quality Agreement of 1978, as amended by Protocol signed November 18, 1987

5. Whole-Fish Benchmark Ranges for Protection of Fish-Eating Wildlife, Compiled by the USGS National Water-Quality Assessment Program **

   Sampling medium:	Whole fish
   Resource protected:	Fish-eating wildlife
   Internet sources:	Whole-Fish Benchmark Ranges for Protection of Fish-Eating Wildlife Derivation (see page 109)

**, This type of benchmarks is used by the NAWQA Program to assess potential effects of measured pesticide concentrations on human health, aquatic life, or fish-eating wildlife.

Contact: Lisa Nowell
lhnowell@usgs.gov, (916) 278-3096