The U.S. Geological Survey (USGS) and the U.S. Environmental Protection Agency (EPA) are collaborating on a field-based study of chemical mixture composition and environmental effects in stream waters affected by a wide range of human activities and contaminant sources.
Scientists sampled 38 streams spanning 24 States and Puerto Rico. Thirty-four of the sites were located in watersheds impacted by multiple contaminant sources, including industrial and municipal wastewater discharges, crop and animal agricultural runoff, urban runoff, and other point and nonpoint contaminant sources. The remaining sites were minimally developed reference watersheds.
Collected samples are undergoing comprehensive chemical and biological characterization, including sensitive and specific direct analysis for over 700 dissolved organic and inorganic chemicals and field parameters, identification of unknown contaminants (environmental forensics), and a variety of screening bioassays to evaluate biological activity and toxicity.
Assessment and management of the risks of exposure to complex chemical mixtures in streams are priorities for human and environmental health organizations around the world. The current lack of information on the composition and variability of environmental mixtures and a limited understanding of their combined effects are fundamental obstacles to timely identification and prevention of adverse human and ecological impacts of exposure to chemical mixtures.
When complete, the results of this collaborative study will help to address these issues. The results of the study will (1) document mixtures and concentrations of chemicals present in the environment, (2) help identify potential human and ecological exposures, (3) guide prioritization of toxicological studies of chemical mixtures, (4) provide insight into potential biological effects of multiple contaminants, (5) help relate biaoassay screening approaches to environmental chemical characterization in support of new monitoring strategies, and (6) provide data for models to predict chemical mixtures in watersheds affected by diverse land- and chemical-use patterns.
This research was funded by the USGS Ecosystems Mission Area’s Environmental Health Program (Contaminant Biology and Toxic Substances Hydrology) and the EPA Office of Research and Development.
Related research is listed below.
Drinking Water and Wastewater Infrastructure Science Team
Sources of Contaminants to Congaree National Park—USGS and National Park Service Working Together
Study Highlights the Complexity of Chemical Mixtures in United States Streams
New Study Measures Crop Bactericide, Nitrapyrin, in Iowa Streams
Bacterial Pathogen Genes in Streams related to Animal Type and Hydrologic Conditions
Synthetic Progestin Affects Fish Reproductive Development and Behavior in Laboratory Exposure Study
Chemical Mixtures and Environmental Effects
Complex Mixtures, Complex Responses—Using Comprehensive Approaches to Assess Pharmaceutical Effects on Fish
Assessing Environmental Chemical Mixtures in United States Streams
Personal Care Products, Pharmaceuticals, and Hormones Move from Septic Systems to Local Groundwater
Chemical Combo and Intersex Fish Found at Smallmouth Bass Nesting Sites
Complex Mixture of Contaminants Persists in Streams Miles from the Source
Below are publications associated with this research.
Chemical mixtures and environmental effects: a pilot study to assess ecological exposure and effects in streams
- Overview
The U.S. Geological Survey (USGS) and the U.S. Environmental Protection Agency (EPA) are collaborating on a field-based study of chemical mixture composition and environmental effects in stream waters affected by a wide range of human activities and contaminant sources.
USGS scientist collects water samples and measures stream-water field parameters at North Sylamore Creek, Arkansas, on January 7, 2014. About 60 sample bottles are filled and shipped to USGS and U.S. Environmental Protection Agency laboratories across the Nation for chemical and biological analysis. Photograph taken by John Tyler Mays, USGS. Scientists sampled 38 streams spanning 24 States and Puerto Rico. Thirty-four of the sites were located in watersheds impacted by multiple contaminant sources, including industrial and municipal wastewater discharges, crop and animal agricultural runoff, urban runoff, and other point and nonpoint contaminant sources. The remaining sites were minimally developed reference watersheds.
Collected samples are undergoing comprehensive chemical and biological characterization, including sensitive and specific direct analysis for over 700 dissolved organic and inorganic chemicals and field parameters, identification of unknown contaminants (environmental forensics), and a variety of screening bioassays to evaluate biological activity and toxicity.
Assessment and management of the risks of exposure to complex chemical mixtures in streams are priorities for human and environmental health organizations around the world. The current lack of information on the composition and variability of environmental mixtures and a limited understanding of their combined effects are fundamental obstacles to timely identification and prevention of adverse human and ecological impacts of exposure to chemical mixtures.
When complete, the results of this collaborative study will help to address these issues. The results of the study will (1) document mixtures and concentrations of chemicals present in the environment, (2) help identify potential human and ecological exposures, (3) guide prioritization of toxicological studies of chemical mixtures, (4) provide insight into potential biological effects of multiple contaminants, (5) help relate biaoassay screening approaches to environmental chemical characterization in support of new monitoring strategies, and (6) provide data for models to predict chemical mixtures in watersheds affected by diverse land- and chemical-use patterns.
This research was funded by the USGS Ecosystems Mission Area’s Environmental Health Program (Contaminant Biology and Toxic Substances Hydrology) and the EPA Office of Research and Development.
- Science
Related research is listed below.
Drinking Water and Wastewater Infrastructure Science Team
The team studies toxicants and pathogens in water resources from their sources, through watersheds, aquifers, and infrastructure to human and wildlife exposures. That information is used to develop decision tools that protect human and wildlife health.Sources of Contaminants to Congaree National Park—USGS and National Park Service Working Together
A National Park Service (NPS) and U.S. Geological Survey (USGS) study determined the concentrations, potential for degradation, and potential for aquatic and terrestrial animal exposure to organic contaminants in water and sediment within the flood-plain/aquatic environments of Congaree National Park which is located downstream from urban and agricultural areas.Study Highlights the Complexity of Chemical Mixtures in United States Streams
A new study highlights the complexity of chemical mixtures in streams and advances the understanding of wildlife and human exposure to complex chemical mixtures.New Study Measures Crop Bactericide, Nitrapyrin, in Iowa Streams
First-ever reconnaissance study documents the off-field transport of nitrapyrin — a nitrification inhibitor applied with fertilizers as a bactericide to kill natural soil bacteria for the purpose of increasing crop yields — to adjacent streams. This study is the first step in understanding the transport, occurrence, and potential effects of nitrapyrin or similar compounds on nitrogen processing in...Bacterial Pathogen Genes in Streams related to Animal Type and Hydrologic Conditions
A U.S. Geological Survey (USGS) study elucidates the influence of animal type and environmental variables on bacterial pathogen occurrence in streams under typical watershed conditions.Synthetic Progestin Affects Fish Reproductive Development and Behavior in Laboratory Exposure Study
Scientists conducted laboratory experiments on levonorgestrel (a synthetic progestin) and observed differential effects to males (reproductive behavior) and females (masculinization) of eastern mosquitofish (Gambusia holbrooki).Chemical Mixtures and Environmental Effects
The USGS is investigating the occurrence and environmental effects of complex mixtures of both natural and man-made chemicals in environmental waters.Complex Mixtures, Complex Responses—Using Comprehensive Approaches to Assess Pharmaceutical Effects on Fish
The occurrence of complex mixtures of prescription pharmaceuticals in streams and rivers around the globe has raised concerns about potential unintended adverse effects on aquatic organisms. The deleterious effects (for example, alteration of fish behavior) observed in this study confirm that effluents containing pharmaceuticals can adversely affect fish in ways that are central to sustaining...Assessing Environmental Chemical Mixtures in United States Streams
The U.S. Geological Survey (USGS) and the U.S. Environmental Protection Agency (EPA) are collaborating on a field-based study of chemical mixture composition and environmental effects in stream waters affected by a wide range of human activities and contaminant sources.Personal Care Products, Pharmaceuticals, and Hormones Move from Septic Systems to Local Groundwater
Pharmaceuticals, hormones, personal care products, and other contaminants of concern associated with everyday household activities were found in adjacent shallow groundwater near two septic system networks in New York (NY) and New England (NE). Factors influencing movement to shallow groundwater and the types of chemicals found include population served by a septic system, site conditions such as...Chemical Combo and Intersex Fish Found at Smallmouth Bass Nesting Sites
Chemical contaminants including herbicides, veterinary pharmaceuticals, and biogenic hormones have been detected at fish nesting sites in the Potomac River watershed where endocrine disruption in smallmouth bass (Micropterus dolomieu) was also observed. Although these contaminants are known to originate from a variety of human and animal-waste sources, results of a recent U.S. Geological Survey...Complex Mixture of Contaminants Persists in Streams Miles from the Source
Natural processes in stream ecosystems such as dilution and microbial degradation are known to attenuate some contaminants to below levels that can cause harm to ecosystems. However, a team of U.S. Geological Survey (USGS) scientists has shown that many chemicals discharged from municipal wastewater treatment facilities persist for miles downstream at levels known, or suspected, to cause adverse... - Publications
Below are publications associated with this research.
Chemical mixtures and environmental effects: a pilot study to assess ecological exposure and effects in streams
Assessment and management of the risks of exposure to complex chemical mixtures in streams are priorities for human and environmental health organizations around the world. The current lack of information on the composition and variability of environmental mixtures and a limited understanding of their combined effects are fundamental obstacles to timely identification and prevention of adverse humAuthorsHerbert T. Buxton, Timothy J. Reilly, Kathryn Kuivila, Dana W. Kolpin, Paul M. Bradley, Daniel L. Villeneuve, Marc A. Mills