Toxic Substances Hydrology Program

Featured Science Activities

Our science activities are summarized in a series of feature articles that highlight recent U.S. Geological Survey (USGS) environmental health science activities. They are short summaries of peer-reviewed journal articles and USGS reports co-authored by our specialized teams of scientists.
Older featured science activities are on our old Web site.

Filter Total Items: 90
Date published: June 20, 2016
Status: Completed

Persistent Contaminant Threats Following Hurricane Sandy—Establishing Baselines and Assessing Impacts

Potential long-term contaminant threats resulting from compromised infrastructure, beach erosion, and sediment disturbance were evaluated in the coastal environments of New Jersey and New York in the aftermath of Hurricane Sandy.

Contacts: Timothy Reilly
Date published: June 16, 2016
Status: Completed

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).

Date published: June 7, 2016
Status: Completed

Distinct Microbiomes Identified in Landfills Throughout the United States

A comprehensive study by U.S. Geological Survey (USGS) and scientists from the University of Oklahoma finds distinct microbial assemblages (microbiomes) in landfill leachate across the United States and investigates factors related to microbiome formation.

Date published: May 31, 2016
Status: Completed

New Study on Cyanotoxins in Lakes and Reservoirs Provides Insights into Assessing Health Risks

Newly published study provides new evidence of the widespread occurrence of cyanotoxins in lakes and reservoirs of the United States and offers new insights into measures used for assessing potential recreational health risks.

Date published: May 12, 2016
Status: Completed

Iodinated Disinfection Byproducts found in Dairy-Impacted Wastewaters and Streams

Iodinated disinfection byproducts were found at stream locations downstream from treated discharge from wastewater treatment plants that receive dairy waste and in the wastewaters directly from dairy facilities.

Date published: May 9, 2016
Status: Completed

Indication of Unconventional Oil and Gas Wastewaters Found in Local Surface Waters

Evidence indicating the presence of wastewaters from unconventional oil and gas (UOG) production was found in surface waters and surficial sediments near an UOG disposal facility in West Virginia.

Date published: April 25, 2016
Status: Completed

Importance of Lake Sediments in Removal of Cyanobacteria, Viruses, and Dissolved Organic Carbon

U.S. Geological Survey (USGS) scientists determined that the colmation layer (top 25 centimeters of lake sediments) was highly effective in removing cyanobacteria, viruses, and dissolved organic carbon during water passage through the lake bottom to aquifer sediments.

Contacts: Ronald W Harvey
Date published: March 31, 2016
Status: Completed

U.S. Geological Survey Identifies Crude-Oil Metabolites in Subsurface Plumes

U.S. Geological Survey (USGS) scientists studying two subsurface crude-oil spill sites in Minnesota measured concentrations of oil breakdown products (metabolites) at greater concentrations than parent compound concentrations.

Date published: March 3, 2016
Status: Completed

U.S. Geological Survey Develops Approach to Assess Baseline Chemical and Radiological Conditions Prior to Uranium Mining near Grand Canyon National Park

U.S. Geological Survey (USGS) scientists developed an approach and collected baseline data to quantitatively assess offsite migration of mine-related contaminants and to identify critical contaminant exposure pathways that could result from uranium mining activities in the Grand Canyon region.

Date published: February 17, 2016
Status: Completed

U.S. Geological Survey Scientists Complete First Systematic Regional Survey of Algal Toxins in Streams of the Southeastern United States

U.S. Geological Survey (USGS) scientists detected microcystin—an algal toxin—in 39 percent of 75 streams assessed in the southeastern United States. These results will inform and become part of a larger, systematic national survey of algal toxins in small streams of the United States.

Date published: January 13, 2016
Status: Completed

North American and European Atmospheric Mercury Declines Explained by Local and Regional Emission Reductions

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.

Date published: December 21, 2015
Status: Completed

Remote Sensing Provides a National View of Cyanobacteria Blooms

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.