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Dive into our publications and explore the science from the Environmental Health Program (Toxic Substances Hydrology and Contaminant Biology).

Filter Total Items: 623

Acetylenotrophic and diazotrophic Bradyrhizobium sp. strain I71 from TCE-contaminated soils

AbstractAcetylene (C2H2) is a molecule rarely found in nature, with very few known natural sources, but acetylenotrophic microorganisms can use acetylene as their primary carbon and energy source. As of 2018 there were 15 known strains of aerobic and anaerobic acetylenotrophs; however, we hypothesize there may yet be unrecognized diversity of acetylenotrophs in nature. This study expands the known
Denise M. Akob, John M. Sutton, Timothy J. Bushman, Shaun Baesman, Edina Klein, Yesha Shrestha, Robert Andrews, Janna L. Fierst, Max Kolton, Sara Gushgari-Doyle, Ronald Oremland, John Freeman

Ecological consequences of neonicotinoid mixtures in streams

Neonicotinoid mixtures are common in streams worldwide, but corresponding ecological responses are poorly understood. We combined experimental and observational studies to narrow this knowledge gap. The mesocosm experiment determined that concentrations of the neonicotinoids imidacloprid and clothianidin (range of exposures, 0 to 11.9 μg/liter) above the hazard concentration for 5% of species (0.0
Travis S. Schmidt, Janet L. Miller, Barbara Mahler, Peter C. Van Metre, Lisa H. Nowell, Mark W. Sandstrom, Daren Carlisle, Patrick W. Moran, Paul Bradley

Pesticide exposure of wild bees and honey bees foraging from field border flowers in intensively managed agriculture areas

Bees are critical for food crop pollination, yet their populations are declining as agricultural practices intensify. Pollinator-attractive field border plantings (e.g. hedgerows and forb strips) can increase bee diversity and abundance in agricultural areas, however recent studies suggest these plants may contain pesticides. Pesticide exposure for wild bees in agricultural areas remains largely u
Laura T. Ward, Michelle Hladik, Aidee Guzman, Sara Winsemius, Ariana Bautista, Claire Kremen, Nicholas Mills

Development and description of a composite hydrogeologic framework for inclusion in a geoenvironmental assessment of undiscovered uranium resources in Pliocene- to Pleistocene-age geologic units of the Texas Coastal Plain

A previously completed mineral resources assessment of the Texas Coastal Plain indicated the potential for the future discovery of uranium resources. Geoenvironmental assessments that include the hydrogeologic framework can be used as a tool to understand the potential effects of mining operations. The hydrogeologic framework for this study focused on the composite hydrogeologic unit of the tract
Andrew Teeple, Kent D Becher, Katherine Walton-Day, Delbert G Humberson, Tanya J. Gallegos

A methodology to assess the historical environmental footprint of in-situ recovery (ISR) of uranium: A demonstration in the Goliad Sand in the Texas Coastal Plain, USA

In-situ recovery (ISR) has been the only technique used to extract uranium from sandstone-hosted uranium deposits in the Pliocene Goliad Sand in the Texas Coastal Plain. Water plays a crucial role throughout the ISR lifecycle of production and groundwater restoration yet neither the water use nor other environmental footprints have been well documented. The goal of this study is to examine histori
Tanya J. Gallegos, Annie Scott, Victoria G. Stengel, Andrew Teeple

Special Issue on PFAS

No abstract available.
Deborah D. Iwanowicz

Temporal variability in TiO2 engineered particle concentrations in rural Edisto River

Titanium dioxide (TiO2) is widely used in engineered particles including engineered nanomaterial (ENM) and pigments, yet its occurrence, concentrations, temporal variability, and fate in natural environmental systems are poorly understood. For three years, we monitored TiO2 concentrations in a rural river basin (Edisto River, < 1% urban land cover) in South Carolina, United States. The total conce
Md Mahmudun Nabi, J. Wang, Celeste A. Journey, Paul Bradley, Mohammed Baalousha

Site- and individual-level contaminations affect infection prevalence of an emerging infectious disease of amphibians

Emerging infectious disease outbreaks are one of multiple stressors responsible for amphibian declines globally. In the northeastern United States, ranaviral diseases are prevalent in amphibians and other ectothermic species, but there is still uncertainty as to whether their presence is leading to population level effects. Further, there is also uncertainty surrounding the potential interactions
Kelly Smalling, Brittany A. Mosher, Luke R. Iwanowicz, Keith Loftin, Adam Boehlke, Michelle Hladik, Carly R. Muletz-Wolz, Nandadevi Córtes-Rodríguez, Robin Femmer, Evan H. Campbell Grant

Temporal trends in macroscopic indicators of fish health in the South Branch of the Potomac River

Over recent decades, the South Branch of the Potomac River, WV, has experienced fish kills and episodes of suppressed health in adult fishes that have spanned small stretches to nearly 120 km of contiguous habitat. Although factors such as endocrine disruption, chemical contaminants, and infectious agents have been detected, no single causal mechanism has been identified. To gain information about
Brandon J. Keplinger, James Hedrick, Vicki S. Blazer

An assessment of uranium in groundwater in the Grand Canyon region

The Grand Canyon region in northern Arizona is a home or sacred place of origin for many Native Americans and is visited by over 6 million tourists each year. Most communities in the area depend upon groundwater for all water uses. Some of the highest-grade uranium ore in the United States also is found in the Grand Canyon region. A withdrawal of over 1 million acres of Federal land in the Gran
Fred D. Tillman, Kimberly R. Beisner, Jessica R. Anderson, Joel A. Unema

Evaluating the effects of replacing septic systems with municipal sewers on groundwater quality in a densely developed coastal neighborhood, Falmouth, Massachusetts, 2016–19

Land disposal of sewage wastewater through septic systems and cesspools is a major cause of elevated concentrations of nitrogen in the shallow coastal aquifers of southern New England. The discharge of nitrogen from these sources at the coast is affecting the environmental health of coastal saltwater bodies. In response, local, State, and Federal agencies are considering expensive actions to mitig
Timothy D. McCobb, Jeffrey R. Barbaro, Denis R. LeBlanc, Marcel Belaval

Watershed-scale risk to aquatic organisms from complex chemical mixtures in the Shenandoah River

River waters contain complex chemical mixtures derived from natural and anthropogenic sources. Aquatic organisms are exposed to the entire chemical composition of the water, resulting in potential effects at the organismal through ecosystem level. This study applied a holistic approach to assess landscape, hydrological, chemical, and biological variables. On-site mobile laboratory experiments were
Larry Barber, Kaycee Elizabeth Faunce, David Bertolatus, Michelle Hladik, Jeramy Jasmann, Steffanie H. Keefe, Dana W. Kolpin, Michael T. Meyer, Jennifer L. Rapp, David A. Roth, Alan M. Vajda