Exposure Pathways

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...

Crab embryos from two Northern California salt marshes accumulate mixtures of currently used as well as discontinued pesticides, according to a study published by U.S. Geological Survey (USGS) and University of California scientists in the journal Environmental Toxicology and Chemistry.

In two separate studies, U.S. Geological Survey (USGS) scientists demonstrated that hormones such as estrogen can biodegrade in stream and groundwater environments. This is an important finding because the science, regulatory, and environmental communities have concerns about the environmental fate of endocrine-disrupting chemicals, such as hormones, in the human wastewaters discharged to the...

An international team of scientists investigating mercury cycling in an experimental watershed in Ontario, Canada, conclusively demonstrated at the ecosystem scale that changes in mercury loadings are expected to result in proportional or near proportional changes in mercury bioaccumulation in fish. Policies to reduce atmospheric emissions of mercury are intended to reduce mercury bioaccumulation...

For some fish living downstream of sewage treatment plants the answer is yes. U.S. Geological Survey (USGS) scientists and their colleagues published a paper in Environmental Science and Technology documenting that specific antidepressants and their degradates found in wastewater discharged into streams by municipal wastewater treatment plants are taken up into the bodies of fish living downstream...

In a 2004-2009 study, U.S. Geological Survey (USGS) scientists found that pharmaceutical manufacturing facilities can be a significant source of pharmaceuticals to the environment. Effluents from two wastewater treatment plants (WWTPs) that receive discharge from pharmaceutical manufacturing facilities (PMFs) had 10 to 1000 times higher concentrations of pharmaceuticals than effluents from 24...

U.S. Geological Survey (USGS) scientists are developing new laboratory analytical methods to measure contaminants in samples of environmental water, sediment, and soil. The work is part of a continuing effort to provide information on new and understudied contaminants to water-resource managers, environmental regulators, and the public. The new methods are used by USGS scientists and others to...

Two national-scale reconnaissance studies recently conducted by the U.S. Geological Survey (USGS) were the first to collect baseline information on the environmental occurrence of pharmaceuticals, personal-care products, detergents, flame retardants, naturally occurring sterols, and other organic contaminants in ground water and untreated sources of drinking water in the United States. These...

Many areas of the Nation are faced with water shortages due to significant demand for water. As a result, supplies are being augmented with treated wastewater for uses such as irrigation. In a study recently published in the journal "Environmental Toxicology and Chemistry," a team of U.S. Geological Survey (USGS) scientists reported that pharmaceuticals in wastewater used for irrigation persist in...

Shallow ground waters in northern climates often have temperatures below 10° Celsius (C) [50° Fahrenheit (F)] during the winter season. The ability of microorganisms to degrade contaminants under these conditions has long been questioned by the scientific community because microbial activity often decreases with decreasing temperatures and because rates of biodegradation typically are assumed to...

U.S. Geological Survey (USGS) scientists completed a variety of groundbreaking studies on the occurrence, fate, and transport of triazine herbicides and their degradates throughout the 1990s. The results of these studies have been summarized and condensed into a USGS report and a book chapter providing, for the first time, a comprehensive snapshot of a decade of this research.

Since the late 1990s, the U.S. Geological Survey (USGS) has conducted an Abandoned Mine Lands (AML) Initiative. The initiative provides technical assistance to support actions by Federal Land Management Agencies in the U.S. Department of the Interior and the U.S. Department of Agriculture (USDA) to remediate contamination associated with abandoned hard-rock mining sites. Acid drainage and toxic...