Endocrine Disrupting Chemicals in the Slick Scum that Covers Stones in Streams Completed
USGS Scientist Holding a Boulder Creek, CO Stone Covered with Biofilm
The slick scum or biofilm that covers most rocks in streams can accumulate contaminants that disrupt reproductive and other endocrine systems in fish. This is the finding of a team of U.S. Geological Survey (USGS) and University of Colorado Boulder scientists as described in a recent article in Environmental Science and Technology (Writer and others, 2011). Biofilms are a mixture of algae, microbes, and organic matter that grow on streambed material such as rocks and stones. The scientists determined that biofilms absorb endocrine disrupting chemicals faster than they can biodegrade them; therefore the chemicals accumulate. Since many fish and other aquatic animals feed on biofilms, the contaminants in biofilms have the potential to be transferred through the food web.
The study took place in Boulder Creek, Colorado. Boulder Creek is similar to many streams around the country in which wastewater contributes a substantial amount (10 to 80 percent) of the water to the stream. The scientists took samples of biofilms, streambed sediments, and water above and below the wastewater discharge outlet on Boulder Creek in hopes of defining the role of biofilms in controlling the movement of contaminants downstream.
Previous studies have shown that wastewater contains a variety of contaminants including endocrine disrupting compounds, and that exposure to wastewater can cause endocrine disruption in fish. The scientists analyzed the samples for two classes of endocrine-disrupting chemicals—hormones (such as 17β-estradiol, estrone, and 17a-ethynylestradiol), and nonylphenols (detergent degradation products such as 4-nonylphenol, 4-nonylphenolmonoethoxylate, and 4-nonylphenoldiethoxylate).
The scientists detected minimal levels of these compounds in biofilms in Boulder Creek upstream of the wastewater discharge. In contrast, many of the compounds downstream of the wastewater outlet were detected at much higher levels. It is interesting to note that many of the hormones were not detected in any of the water samples, both upstream and downstream, but were detected in the biofilms. This shows that the biofilms efficiently accumulate hormones from water and can play a major role in understanding the impact of these chemicals on aquatic organisms.
This study was funded by the USGS’s Toxic Substances Hydrology Program and National Research Program, and by the National Science Foundation (Grant No. CBET-0854527).
Related Science is listed below.
Complex Mixture of Contaminants Persists in Streams Miles from the Source
Hormones in Land-Applied Biosolids Could Affect Aquatic Organisms
New Knowledge on the Fate and Transport of Emerging Contaminants in Rivers
Improvements in Wastewater Treatment Reduces Endocrine Disruption in Fish
Antibiotics in Groundwater Affect Natural Bacteria
Evidence of Endocrine Disruption Unexpectedly Found in Minnesota Lakes
Related publications are listed below.
Below are news stories associated with this project.
- Overview
The slick scum or biofilm that covers most rocks in streams can accumulate contaminants that disrupt reproductive and other endocrine systems in fish. This is the finding of a team of U.S. Geological Survey (USGS) and University of Colorado Boulder scientists as described in a recent article in Environmental Science and Technology (Writer and others, 2011). Biofilms are a mixture of algae, microbes, and organic matter that grow on streambed material such as rocks and stones. The scientists determined that biofilms absorb endocrine disrupting chemicals faster than they can biodegrade them; therefore the chemicals accumulate. Since many fish and other aquatic animals feed on biofilms, the contaminants in biofilms have the potential to be transferred through the food web.
The study took place in Boulder Creek, Colorado. Boulder Creek is similar to many streams around the country in which wastewater contributes a substantial amount (10 to 80 percent) of the water to the stream. The scientists took samples of biofilms, streambed sediments, and water above and below the wastewater discharge outlet on Boulder Creek in hopes of defining the role of biofilms in controlling the movement of contaminants downstream.
Previous studies have shown that wastewater contains a variety of contaminants including endocrine disrupting compounds, and that exposure to wastewater can cause endocrine disruption in fish. The scientists analyzed the samples for two classes of endocrine-disrupting chemicals—hormones (such as 17β-estradiol, estrone, and 17a-ethynylestradiol), and nonylphenols (detergent degradation products such as 4-nonylphenol, 4-nonylphenolmonoethoxylate, and 4-nonylphenoldiethoxylate).
The scientists detected minimal levels of these compounds in biofilms in Boulder Creek upstream of the wastewater discharge. In contrast, many of the compounds downstream of the wastewater outlet were detected at much higher levels. It is interesting to note that many of the hormones were not detected in any of the water samples, both upstream and downstream, but were detected in the biofilms. This shows that the biofilms efficiently accumulate hormones from water and can play a major role in understanding the impact of these chemicals on aquatic organisms.
This study was funded by the USGS’s Toxic Substances Hydrology Program and National Research Program, and by the National Science Foundation (Grant No. CBET-0854527).
- Science
Related Science is listed below.
Filter Total Items: 18Complex 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...Hormones in Land-Applied Biosolids Could Affect Aquatic Organisms
Hormones from biosolids applied to fields may be present in rainfall runoff at concentrations that are high enough to impact the health of aquatic organisms if the runoff reaches streams, report scientists from the U.S. Geological Survey (USGS) and Colorado State University in Environmental Science and Technology . Artificial rainfall runoff from agricultural test plots where biosolids were...New Knowledge on the Fate and Transport of Emerging Contaminants in Rivers
A detergent degradation product (4-nonylphenol) and a biogenic hormone (17β-estradiol) added to the Redwood River, Minnesota, were attenuated by biodegradation and other natural processes. These are the findings of a team of U.S. Geological Survey (USGS) and University of Colorado scientists.Improvements in Wastewater Treatment Reduces Endocrine Disruption in Fish
A team of scientists from the U.S. Geological Survey (USGS), the University of Colorado, and the City of Boulder, Colorado, demonstrated that improvements to the treatment process at a wastewater treatment facility (WWTF) reduced the level of endocrine disruption in fish exposed to wastewater effluent discharged from the facility. It is difficult to anticipate the effects that upgrading WWTF...Antibiotics in Groundwater Affect Natural Bacteria
U.S. Geological Survey (USGS) scientists have documented adverse health effects on populations of native soil bacteria exposed to levels of the antibiotic (SMX) below those used to treat diseases (subtherapeutic). Because SMX has been found in environmental waters by many previous studies, the scientists conducted laboratory exposure experiments to determine the effect of SMX on native bacteria...Evidence of Endocrine Disruption Unexpectedly Found in Minnesota Lakes
Endocrine disrupting chemicals and indicators of endocrine disruption were found in several Minnesota lakes with surrounding urban, residential, agricultural, and forested land uses. The lakes do not directly receive discharges from industries or wastewater-treatment plants; however, they are used for recreation, and they receive water from widely scattered sources. The presence of both male and... - Publications
Related publications are listed below.
- News
Below are news stories associated with this project.