On February 17, 2016, the U.S. Geological Survey (USGS) announced that the microcystin toxins, produced by Cyanobacteria—also known as blue-green algae—were found in 39 percent of 75 streams in the southeastern United States from which samples were taken from August to October 2014. The streams sampled are located in Alabama, Georgia, North Carolina, South Carolina, and Virginia.
Following is an excerpt from the USGS’ news release on the research:
“Microcystins are a well-known public health concern. Public health practitioners and medical researchers have observed a range of symptoms in humans after exposure to microcystins. Symptoms can include nausea, dermatitis and, in severe cases, liver failure. Toxicity issues have been reported for humans, companion animals, livestock and wildlife.
“Although the maximum microcystin concentration measured in this study (3.2 µg/L) did not exceed World Health Organization moderate risk thresholds (10 µg/L) in the streams sampled, further research is needed to understand the potential effects on water quality and related environmental health concerns in downstream aquatic ecosystems, lakes, and drinking water reservoirs. …
“This is the first of several regional assessments of algal toxins, which will provide context for the design of future environmental health studies. These studies will investigate land-use and other factors that may influence or create new environmental pathways of exposures to cyanobacteria and associated toxins. Ongoing work by the USGS in the Pacific Northwest and planned work in the northeastern United States and California will expand our understanding of cyanobacteria and toxins in a wider variety of aquatic ecosystems.”
Sources used and for more information:
Algal Toxins Detected in One-Third of Streams Assessed in Southeastern United States, U.S. Geological Survey News Release, 2/17/16.
U.S. Geological Survey Scientists Complete First Systematic Regional Survey of Algal Toxins in Streams of the Southeastern United States, USGS Science Feature, 2/17/16 (many additional sources of information are listed at this link).
U.S. Geological Survey (USGS) scientists sampling for microcystin toxins in the Enoree River near Pelham, South Carolina (Spartanburg County). Photo by Dianna Jarvis, USGS, accessed online at http://toxics.usgs.gov/highlights/2016-02-17-algal_toxins_in_streams.html, 2/17/16.