Toxic Substances Hydrology

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.

Filter Total Items: 214
Date published: April 6, 2021
Status: Completed

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...

Date published: March 16, 2021
Status: Completed

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.

Date published: March 8, 2021
Status: Completed

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.

Date published: March 3, 2021
Status: Completed

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. 

Date published: March 1, 2021
Status: Completed

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.


Date published: February 17, 2021
Status: Active

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...

Contacts: Josh T Ackerman
Date published: February 17, 2021
Status: Active

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.


Date published: February 16, 2021
Status: Completed

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.  


Date published: January 13, 2021
Status: Active

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.

Date published: August 26, 2020
Status: Active

Conceptual Model Developed to Understand Contaminant Pathways between Aquatic and Terrestrial Ecosystems

A conceptual model, based on contaminant properties and ecotoxicological principles, was developed to understand the transfer of contaminants from aquatic to terrestrial ecosystems and the effects of various classes of contaminants on terrestrial insectivores living near contaminated freshwaters.

Date published: August 26, 2020
Status: Completed

Review of Cyanobacterial Neurotoxins—Information for Prioritizing Future Science Directions

The current state of knowledge on the modes of action, production, fate, and occurrence of the freshwater cyanobacterial neurotoxins, anatoxin-a and saxitoxin, was reviewed and synthesized to identify gaps and critical research needs to better understand the health effects of algal toxins.