Exposure Pathways

Recent findings from a consortium of university, State, and U.S. Geological Survey (USGS) scientists indicate that declining atmospheric concentrations of mercury (Hg) can be explained by the phaseout of mercury in many commercial products and by reduced emissions from utilities over the past two decades.

Four Federal agencies, including the U.S. Geological Survey (USGS), are collaborating to transform satellite data into information managers can use to protect ecological and human health from freshwater contaminated by harmful algal blooms.

Experimental field research simulating hydrocarbon spills by researchers from the U.S. Geological Survey (USGS), Virginia Tech , and the University of St. Thomas showed that mixed ethanol and petroleum-based fuels increased the rate by which arsenic and other natural trace elements are released from aquifer sediments to groundwater when compared to petroleum-based fuels alone.

The US Geological Survey (USGS) and collaborators at the University of Wisconsin-Madison have developed a new tool for attributing (fingerprinting) mercury sources to the Great Lakes. This new fingerprinting tool helps resource managers understand which mitigation strategies will be most effective for reducing mercury loading and exposure to fish and wildlife.

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...

New scientific research from the U.S. Geological Survey (USGS) details how landfill leachate, disposed from landfills to environmental pathways, is host to numerous contaminants of emerging concern (CECs).

A recent reconnaissance study by the U.S. Geological Survey (USGS) demonstrates the first observed occurrence of pesticides, including neonicotinoid insecticides, in wild-caught native bees. The results indicate that native bees collected in an agricultural landscape are exposed to multiple pesticides including insecticides, fungicides, and herbicides. This reconnaissance study is the first step...

Neonicotinoid insecticides (neonicotinoids) were present in a little more than half of the streams sampled across the United States and Puerto Rico, according to a new U.S. Geological Survey (USGS) study. This is the first national-scale study of the presence of neonicotinoids in urban and agricultural land use settings across the Nation and was completed as part of ongoing USGS investigations of...

U.S. Geological Survey (USGS) scientists determined that endocrine disrupting chemicals (EDCs) were present in wastewater treatment plant (WWTP) effluent, water, and fish tissue in urban waterways in the Great Lakes and upper Mississippi River Regions (Indiana, Illinois, Michigan, Minnesota, and Ohio) during 1999 through 2009.

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.

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...

A new USGS report, Mercury in the Nation's Streams—Levels, Trends, and Implications, presents a comprehensive assessment of mercury contamination in streams across the United States. It highlights the importance of environmental processes, monitoring, and control strategies for understanding and reducing stream mercury levels. This report summarizes selected stream studies conducted by the U.S...