Pesticides and Water Quality Active
Pesticides are chemicals designed to kill pests, including insects (insecticides), weeds (herbicides), and fungi (fungicides). The USGS assesses the occurrence and behavior of pesticides in streams, lakes, and groundwater and the potential for pesticides to contaminate our drinking-water supplies or harm aquatic ecosystems.
NOTICE: The USGS agricultural pesticide-use estimates are supported by funding from the USGS National Water Quality Program for the purpose of better understanding pesticides in freshwater and their impact on water availability nationwide. The USGS recently updated its plan to publish pesticide-use estimates. Final annual pesticide-use estimates, for approximately 400 compounds, from 2018-22 will be published in 2025. After that, preliminary estimates will be published annually and later updated with final estimates once the USDA Census of Agriculture is released (every five years). The total number of pesticides included in the analysis will fluctuate annually, based on data availability from our pesticide use survey contract provider. (Updated February 27, 2024)
Pesticides are used in agriculture, in homes and businesses, on lawns and gardens, along roads, in recreational areas, and on pets and livestock. There are hundreds of different pesticide chemicals in use in the United States. In 2007, about 390 million kilograms (430,000 tons) of pesticides, including herbicides, insecticides, and fungicides, were used in the United States. Pesticides released into the environment for agricultural and nonagricultural purposes can contaminate surface water and groundwater, which are critical sources of drinking water.
The USGS, through its National Water Quality Program, researches numerous aspects of pesticides and water quality, and has developed maps, graphics, and tools to aid in understanding where pesticides occur, at what concentrations, and potential consequences.
- Pesticide Use: The tables, maps, and graphs provided on this web site provide estimates of agricultural pesticide use in the conterminous United States for hundreds of pesticides.
- Trends in Pesticide Occurrence in Streams: Use the online tool to view a national maps of trends in pesticide concentrations in streams.
- Concentrations of Pesticides in Water of Potential Human-Health Concern: This searchable online database provides Health-Based Screening Levels (HBSLs) for hundreds of chemicals, including pesticides and degradates.
- Pesticide Toxicity to Aquatic Organisms: The Pesticide Toxicity Index (PTI) can be used to assess the potential toxicity of pesticide mixtures in water to freshwater aquatic organisms. Benchmarks also are available for pesticides in sediment.
- Pesticides and Stream Ecology: The Regional Stream Quality Assessment (RSQA) is assessing how chemical stressors, such as pesticides and nutrients, and physical stressors, such as disturbed streambanks and sedimentation, are affecting the aquatic organisms that live in small streams across the United States.
- Pesticides and Lake Sediment: Many pesticides dissolve in water, but some pesticides, like DDT and chlordane, adhere to sediment and persist for years in the bed sediments of stream and lakes, recording the history of contaminant use in watershed.
Learn more about USGS research on pesticides and related water-quality topics at the web pages below.
Below, you'll find links to data sets developed for investigation of pesticides.
Below, you’ll find the latest in peer-reviewed journal articles and USGS reports on pesticides and water quality. For more publications on this topic, search the USGS Publications Warehouse.
Major herbicides in ground water: Results from the National Water-Quality Assessment
National-scale, field-based evaluation of the biota - Sediment accumulation factor model
The behaviour of 39 pesticides in surface waters as a function of scale
Effect of scale on the behavior of atrazine in surface waters
Pesticides in ground water of the United States, 1992-1996
Method for estimating pesticide use for county areas of the conterminous United States
Organochlorine pesticides and PCBs in stream sediment and aquatic biota—initial results from the National Water-Quality Assessment Program, 1992–1995
Pesticides in stream sediment and aquatic biota— Current understanding of distribution and major influences
Summary and evaluation of pesticides in field blanks collected for the National Water-Quality Assessment Program, 1992-95
The quality of our nation's waters: Nutrients and pesticides
Pesticides in streams of the United States : initial results from the National Water-Quality Assessment Program
Agrichemicals in ground water of the midwestern USA: Relations to soil characteristics
Pesticide science in the news! Read recent highlights.
- Overview
Pesticides are chemicals designed to kill pests, including insects (insecticides), weeds (herbicides), and fungi (fungicides). The USGS assesses the occurrence and behavior of pesticides in streams, lakes, and groundwater and the potential for pesticides to contaminate our drinking-water supplies or harm aquatic ecosystems.
NOTICE: The USGS agricultural pesticide-use estimates are supported by funding from the USGS National Water Quality Program for the purpose of better understanding pesticides in freshwater and their impact on water availability nationwide. The USGS recently updated its plan to publish pesticide-use estimates. Final annual pesticide-use estimates, for approximately 400 compounds, from 2018-22 will be published in 2025. After that, preliminary estimates will be published annually and later updated with final estimates once the USDA Census of Agriculture is released (every five years). The total number of pesticides included in the analysis will fluctuate annually, based on data availability from our pesticide use survey contract provider. (Updated February 27, 2024)
Pesticides are used in agriculture, in homes and businesses, on lawns and gardens, along roads, in recreational areas, and on pets and livestock. There are hundreds of different pesticide chemicals in use in the United States. In 2007, about 390 million kilograms (430,000 tons) of pesticides, including herbicides, insecticides, and fungicides, were used in the United States. Pesticides released into the environment for agricultural and nonagricultural purposes can contaminate surface water and groundwater, which are critical sources of drinking water.
The USGS, through its National Water Quality Program, researches numerous aspects of pesticides and water quality, and has developed maps, graphics, and tools to aid in understanding where pesticides occur, at what concentrations, and potential consequences.
- Pesticide Use: The tables, maps, and graphs provided on this web site provide estimates of agricultural pesticide use in the conterminous United States for hundreds of pesticides.
- Trends in Pesticide Occurrence in Streams: Use the online tool to view a national maps of trends in pesticide concentrations in streams.
- Concentrations of Pesticides in Water of Potential Human-Health Concern: This searchable online database provides Health-Based Screening Levels (HBSLs) for hundreds of chemicals, including pesticides and degradates.
- Pesticide Toxicity to Aquatic Organisms: The Pesticide Toxicity Index (PTI) can be used to assess the potential toxicity of pesticide mixtures in water to freshwater aquatic organisms. Benchmarks also are available for pesticides in sediment.
- Pesticides and Stream Ecology: The Regional Stream Quality Assessment (RSQA) is assessing how chemical stressors, such as pesticides and nutrients, and physical stressors, such as disturbed streambanks and sedimentation, are affecting the aquatic organisms that live in small streams across the United States.
- Pesticides and Lake Sediment: Many pesticides dissolve in water, but some pesticides, like DDT and chlordane, adhere to sediment and persist for years in the bed sediments of stream and lakes, recording the history of contaminant use in watershed.
- Science
Learn more about USGS research on pesticides and related water-quality topics at the web pages below.
- Data
Below, you'll find links to data sets developed for investigation of pesticides.
- Publications
Below, you’ll find the latest in peer-reviewed journal articles and USGS reports on pesticides and water quality. For more publications on this topic, search the USGS Publications Warehouse.
Filter Total Items: 116Major herbicides in ground water: Results from the National Water-Quality Assessment
To improve understanding of the factors affecting pesticide occurrence in ground water, patterns of detection were examined for selected herbicides, based primarily on results from the National Water-Quality Assessment (NAWQA) program. The NAWQA data were derived from 2227 sites (wells and springs) sampled in 20 major hydrologic basins across the USA from 1993 to 1995. Results are presented for siAuthorsJ.E. Barbash, G.P. Thelin, D.W. Kolpin, R. J. GilliomNational-scale, field-based evaluation of the biota - Sediment accumulation factor model
The biota - sediment accumulation factor (BSAF) model has been suggested as a simple tool to predict bioaccumulation of hydrophobic organic compounds (HOCs)in fish and other aquatic biota from measured concentrations in sediment based on equilibrium partitioning between the sediment organic carbon and biotic lipid pools. Currently, evaluation of this model as a predictive tool has been limited toAuthorsCharles S. Wong, Paul D. Capel, Lisa H. NowellThe behaviour of 39 pesticides in surface waters as a function of scale
A portion of applied pesticides runs off agricultural fields and is transported through surface waters. In this study, the behaviour of 39 pesticides is examined as a function of scale across 14 orders of magnitude from the field to the ocean. Data on pesticide loads in streams from two US Geological Survey programs were combined with literature data from field and watershed studies. The annual loAuthorsP. D. Capel, S.J. Larson, T. A. WintersteinEffect of scale on the behavior of atrazine in surface waters
Field runoff is an important transport mechanism by which agricultural pesticides, including atrazine, move into the hydrologic environment. Atrazine is chosen because it is widely used, is transported in runoff relatively easily, is widely observed in surface waters, and has relatively little loss in the stream network. Data on runoff of atrazine from experimental plot and field studies is combinAuthorsP. D. Capel, S.J. LarsonPesticides in ground water of the United States, 1992-1996
During the first cycle of the National Water Quality Assessment (1992–1996), ground water in 20 of the nation's major hydro-logic basins was analyzed for 90 pesticide compounds (pesticides and degradates). One or more of the pesticide compounds examined were detected at 48.4% of the 2485 ground water sites sampled. However, approximately 70% of the sites where pesticides were detected, two or moreAuthorsDana W. Kolpin, Jack E. Barbash, Robert J. GilliomMethod for estimating pesticide use for county areas of the conterminous United States
Information on the amount and distribution of pesticide compounds used throughout the United States is essential to evaluate the relation between water quality and pesticide use. This information is the basis of the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program studies of the effects of pesticides on water quality in 57 major hydrologic systems, or study units, locatedAuthorsGail P. Thelin, Leonard P. GianessiOrganochlorine pesticides and PCBs in stream sediment and aquatic biota—initial results from the National Water-Quality Assessment Program, 1992–1995
One of the goals of the National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey is to assess the status and trends in the nation's water quality and to understand the natural and anthropogenic factors that affect water-quality conditions. This report summarizes the occurrence and distribution of 33 organochlorine compounds in fluvial bed sediment and aquatic biota (whole frAuthorsCharles S. Wong, Paul D. Capel, Lisa H. NowellPesticides in stream sediment and aquatic biota— Current understanding of distribution and major influences
This report summarizes a comprehensive analysis of existing information on pesticides in bed sediment and aquatic biota of United States rivers and streams: their geographic distribution, sources, trends, environmental fate, and biological significance. It is one of a four-part series that synthesizes current knowledge and understanding of pesticides in the nation’s water resources as part of theAuthorsLisa H. Nowell, Paul D. Capel, Peter D. DileanisSummary and evaluation of pesticides in field blanks collected for the National Water-Quality Assessment Program, 1992-95
Field blanks are quality-control samples used to assess contamination in environmental water samples. Contamination is the unintentional introduction of a chemical (pesticides in this instance) into an environmental water sample from sources such as inadequately cleaned equipment, dirty hands, dust, rain, or fumes. Contamination causes a positive bias in analytical measurements that may need to beAuthorsJeffrey D. Martin, Robert J. Gilliom, Terry L. SchertzThe quality of our nation's waters: Nutrients and pesticides
This report is the first in a series of nontechnical publications, 'The quality of our nation's waters,' designed to describe major findings of the National Water-Quality Assessment Program regarding water-quality issues of regional and national concern. Sources, seasonal and geographic patterns of occurrence, and long-term trends are evaluated for nutrients and pesticides in streams and ground waAuthorsPesticides in streams of the United States : initial results from the National Water-Quality Assessment Program
Water samples from 58 rivers and streams across the United States were analyzed for pesticides as part of the National Water-Quality Assessment Program of the U.S. Geological Survey. The sampling sites represent 37 diverse agricultural basins, 11 urban basins, and 10 basins with mixed land use. Forty-six pesticides and pesticide degradation products were analyzed in approximately 2,200 samples colAuthorsSteven J. Larson, Robert J. Gilliom, Paul D. CapelAgrichemicals in ground water of the midwestern USA: Relations to soil characteristics
A comprehensive set of soil characteristics were examined to determine the effect of soil on the transport of agrichemicals to ground water. This paper examines the relation of local soil characteristics to concentrations and occurrence of nitrate, atrazine (2-chloro-4 ethylamino-6-isopropylamino-s-trazine), and atrazine residue [atrazine + deethylatrazine (2-amino-4-chloro-6-isopropylamino-s-triaAuthorsM. R. Burkart, D.W. Kolpin, R.J. Jaquis, K.J. Cole - News
Pesticide science in the news! Read recent highlights.