Toxic Substances Hydrology
Learn About Our Science Activities
Toxic Substances Hydrology Featured Science Activities
Our science is 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.
Browse Toxic Substances Hydrology Featured Science Activities science related to:
Bioaccumulation of Mercury in Fish Varied by Species and Location in the Chesapeake Bay Watershed—Summary of Existing Data and a Roadmap for Integrated Monitoring
Fish mercury data from State monitoring programs and research studies within the Chesapeake Bay were compiled and summarized to provide a comprehensive overview of the variation in fish mercury concentrations among species and habitats within the watershed. These data are put into context with existing health benchmarks for humans, birds, and fish. Scientists also provide a roadmap for an...
Flood Redistributes Mercury in Grand Canyon Aquatic Food Webs
Scientists coupled the concepts of energy flow through food webs with measurements of mercury in organic matter and animals to estimate mercury fluxes and fate during an experimental flood in the Colorado River. The flood redistributed mercury in simple, upstream food webs but not in more complex, downstream food webs.
Science to Understand Low-Level Exposures to Neonicotinoid Pesticides, their Metabolites, and Chlorinated Byproducts in Drinking Water
Scientists reported the discovery of three neonicotinoid pesticides in drinking water and their potential for transformation and removal during water treatment. The research provides new insights into the persistence of neonicotinoids and their potential for transformation during water treatment and distribution, while also identifying granulated activated carbon as a potentially effective...
Clothianidin Exposure Associated with Changes in Tadpole Behavior
During a laboratory exposure study, tadpole movement decreased with increased concentrations of clothianidin, a neonicotinoid pesticide. Decreased movement could affect a tadpole’s ability to forage, escape predation, and metamorphose before ponds dry.
Framework Developed to Evaluate the Practicality of Effects-Directed Analyses to Identify Endocrine Active Chemicals in Complex Environmental Sample Mixtures
An effects-directed analyses (EDA) framework for endocrine active chemicals was developed to help decision makers quickly evaluate the efficacy and practicality of an EDA approach in waste and surface waters and how adjustments could be made to increase its success.
Per/polyfluoroalkyl Substances (PFAS) in Residential Tap Water: Source-to-Tap Science for Underserved Communities
Per- and polyfluoroalkyl substances (PFAS) were detected at low levels in treated drinking water samples from residential taps in the Greater Chicago Area. This study is part of a larger approach to provide an understanding of contaminant mixtures in residential tap water across the Nation including underserved communities in rural, urban, and tribal areas.
Bird Hatchling Development Following Exposure to Environmentally Relevant Levels of Brominated Flame Retardants
Scientists performed laboratory studies with American kestrels and zebra finch to determine the effects of brominated flame retardant exposure on hatchlings. They found evidence that exposure while in the egg disrupted thyroid function in female American kestrel hatchlings and affected nestling body condition in zebra finch hatchlings, but no other effects were detected.
...
Wetland Management Technique Designed to Reduce Mercury in Water and Fish Tested During a Short-Term Field Study
Results from a 3-year study indicate there was support for the use of open- and deep-water treatment pools at the downstream end of seasonal wetlands to reduce methylmercury concentrations in water exported from the wetlands, but the treatment had no measurable effect on wetland fish. Questions remain about the long-term potential for mercury removal using this wetland management strategy...
Technique Used to Distinguish Natural Background from Human-Caused Enrichment of Trace Elements in Soils
Human activities can enrich toxic trace elements like uranium and arsenic in the environment, but these elements also are from natural sources and occur at background levels. Scientists utilized a technique that identifies the background and the elemental fingerprint of human-caused enrichment and tested the new technique on data collected near uranium mines in Arizona.
Mercury Accumulation in Waterbirds (Black Rails) Related to Sediment Chemistry in San Francisco Bay Wetlands
The U.S. Geological Survey (USGS) assessed the effect of sediment chemistry, food web structure, and diet on mercury bioaccumulation in black rails in the San Francisco Bay watershed. Differences in mercury accumulation in the birds were related to differences in sediment chemistry in the wetlands.
New Virus Identified in Melanistic Skin Lesions on Smallmouth Bass from the Chesapeake Bay Watershed
Environmental Health Program Drinking Water Science
Drinking water in the United States rarely is tested for contaminants and pathogens at the tap, where human exposure can occur. In this special issue, we present the science to help understand contaminants and pathogens in drinking water at business and residential taps.