GeoHEALTH-USGS Newsletter, July 2021
Assessment of Mercury and Selenium Accumulation in Upper Colorado River Basin Fish
More than 50 years of existing mercury and selenium concentrations in native and nonnative fish species residing in streams within the Upper Colorado River Basin were compiled and analyzed to provide an understanding of concentrations among different species, sampling years, and locations to determine potential health risks. Concentrations of mercury and selenium were above health benchmarks in 13 percent and 48 percent of individual fish, respectively, suggesting the health of some fishes may be impaired by these contaminants.
Scientists Provide an Understanding of Anticoagulant Rodenticide Exposure in Non-Target Bird Species
U.S. Geological Survey scientists and their partners utilize laboratory and field studies and existing information to improve understanding of anticoagulant rodenticide exposure and effects to wild birds.
Long-Term Monitoring Reveals How Water and Biota in Remote Lakes Respond Differently to Changes in Atmospheric Deposition of Mercury
A comparison of regional mercury atmospheric deposition data with water, yellow perch, and dragonfly larvae samples from lakes in Voyageurs National Park indicates that decreases in mercury emissions resulted in mercury reduction in water from these remote lakes, but mercury declines in biota were significant in only one of three lakes, likely because resident biota integrate exposure over much longer time periods.
Ecotoxicology and Ecological Risks of Per‐ and Polyfluoroalkyl Substances
Ecotoxicology and ecological risks of per- and polyfluoroalkyl substances are summarized to highlight critical gaps and uncertainties, and to provide potential approaches to fill those gaps, including the development of targeted monitoring programs and cross-disciplinary approaches.
Do Trace Metal Concentrations in the Upper Columbia River Affect Early Life Stage White Sturgeon?
To understand if contaminants are associated with white sturgeon population declines, U.S. Geological Survey scientists reviewed the life history, physiology, and behavior of white sturgeon, along with recent toxicological studies and existing trace metal data for locations in the Columbia River. The analysis indicated that the highest concentrations of copper and other metals in the Columbia River were measured at the water-sediment interface, which may, along with other stressors, present a potential threat to the health of juvenile white sturgeon.
Groundwater Discharge is a Pathway for Phytoestrogen and Herbicide Entry to Streams in the Chesapeake Bay Watershed
Groundwater discharge zones are important spawning areas for fish because they provide a thermally stable habitat. Research at three streams in the Chesapeake Bay Watershed with areas of focused groundwater discharge revealed that groundwater also is a source of phytoestrogens and herbicides that could result in fish exposure during sensitive life stages.
Geochemical Signatures of Oil and Gas Wastewater from an Accidental Release Detected in Stream Sediment and Pore Waters Two Years Post Spill
Scientists identified geochemical signatures of wastewater in Blacktail Creek, North Dakota, as a result of a 2015 pipeline leak. They demonstrated that environmental signatures from wastewater spills are persistent within a short (1-3 year) time frame, can enter the creek through subsurface pathways, and can create the potential for extended environmental exposures.
Inorganic and Organic Chemical Mixtures Detected in both Public and Private Tap Water in Cape Cod, Massachusetts
Multiple detections of regulated and unregulated chemical (inorganic, organic) analytes or elements were detected in both privately and publicly supplied tap water samples from 20 residences in Cape Cod, Massachusetts that share a common source of water.
