Exposure Pathways

New report provides photographic documentation and identification of the cyanobacteria present in Lake Okeechobee, the Caloosahatchee River, and St. Lucie Canal during an extensive algal bloom in 2016.

The amino acid β-methylamino-L-alanine (BMAA) is produced by cyanobacteria and has been suggested by human health researchers as a causal factor for degenerative neurological diseases such as Amyotrophic Lateral Sclerosis (ALS), Parkinsonism, and dementia. An objective review concluded that this hypothesis is not supported by existing data.

Dr. Isabelle M. Cozzarelli received the U.S. Department of Interior's second highest honorary award—the Meritorious Service Award—for her numerous contributions to understanding the biogeochemical controls of contaminant degradation in groundwater and near-surface environments.

The U.S. Geological Survey (USGS) 2016 Early Career Excellence in Leadership Award was given to Dr. Denise M. Akob and Dr. Karl B. Haase. Drs. Akob and Haase have demonstrated outstanding leadership through their scientific accomplishments and service to the USGS.

Human enteric and bovine-specific viruses were detected in eight Great Lakes tributaries. Presence and concentration of human viruses increased in watersheds with greater than 25 percent urban influence and more than 2,900 people per square kilometer. Similarly, bovine viruses increased in watersheds having greater than 40 percent agricultural land influence and cattle densities greater than 50...

The Chesapeake Bay is the largest estuary in the United States and provides critical resources to fish, wildlife and people. For more than a decade, recreational fish species have been plagued with skin lesions and intersex conditions (the presence of male and female sex characteristics in the same fish) that biologists attributed to exposures to endocrine disrupting chemicals (EDCs)...

A new study highlights the complexity of chemical mixtures in streams and advances the understanding of wildlife and human exposure to complex chemical mixtures.

Study examines the potential adverse effects of fungicides on leaf decomposition by microbes and aquatic invertebrates.

Shifts in the overall microbial community structure were present in stream sediments that contained chemicals associated with unconventional oil and gas wastewaters. This work is part of a long-term study designed to understand persistence of chemicals from oil and gas wastewaters in sediments and water and how those factors might be related to exposures and adverse health effects, if any, on...

The addition of nitrate in a low oxygen groundwater resulted in the immobilization of naturally occurring dissolved arsenic and the conversion of nitrate to innocuous nitrogen gas.

A new study measures the transport of chemicals associated with unconventional oil and gas (UOG) produced waters downstream from a pipeline leak in North Dakota. This work is part of a long-term study designed to understand chemical persistence in sediments and water and how those factors might be related to contaminant exposures and associated with adverse health effects, if any, on organisms.

The presence of indicator bacteria, hepatitis E virus (HEV), and numerous bacterial pathogen genes increased following precipitation-induced runoff events in streams draining adjacent land surfaces in Iowa where swine manure was recently applied.