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Mercury and Selenium are Accumulating in the Colorado River Food Web of the Grand Canyon
http://www.usgs.gov/newsroom/article.asp?ID=4303&from=rss[font face=Serif][font size=5]Mercury and Selenium are Accumulating in the Colorado River Food Web of the Grand Canyon[/font]
Released: 8/19/2015 1:24:35 PM
Contact Information:
U.S. Department of the Interior, U.S. Geological Survey
Office of Communications and Publishing
12201 Sunrise Valley Dr, MS 119
Reston, VA 20192
[font size=3]Although the Grand Canyon segment of the Colorado River features one of the most remote ecosystems in the United States, it is not immune to exposure from toxic chemicals such as mercury according to newly published research in Environmental Toxicology and Chemistry.
The study, led by the U.S. Geological Survey, found that concentrations of mercury and selenium in Colorado River food webs of the Grand Canyon National Park, regularly exceeded risk thresholds for fish and wildlife. These risk thresholds indicate the concentrations of toxins in food that could be harmful if eaten by fish, wildlife and humans. These findings add to a growing body of research demonstrating that remote ecosystems are vulnerable to long-range transport and bioaccumulation of contaminants.
“Managing exposure risks in the Grand Canyon will be a challenge, because sources and transport mechanisms of mercury and selenium extend far beyond Grand Canyon boundaries,” said Dr. David Walters, USGS research ecologist and lead author of the study.
David Uberuaga, superintendent of Grand Canyon National Park, added, “studies like this continue to educate the public and highlight the threats that face the park and its resources."
…[/font][/font]
Released: 8/19/2015 1:24:35 PM
Contact Information:
U.S. Department of the Interior, U.S. Geological Survey
Office of Communications and Publishing
12201 Sunrise Valley Dr, MS 119
Reston, VA 20192
[font size=3]Although the Grand Canyon segment of the Colorado River features one of the most remote ecosystems in the United States, it is not immune to exposure from toxic chemicals such as mercury according to newly published research in Environmental Toxicology and Chemistry.
The study, led by the U.S. Geological Survey, found that concentrations of mercury and selenium in Colorado River food webs of the Grand Canyon National Park, regularly exceeded risk thresholds for fish and wildlife. These risk thresholds indicate the concentrations of toxins in food that could be harmful if eaten by fish, wildlife and humans. These findings add to a growing body of research demonstrating that remote ecosystems are vulnerable to long-range transport and bioaccumulation of contaminants.
“Managing exposure risks in the Grand Canyon will be a challenge, because sources and transport mechanisms of mercury and selenium extend far beyond Grand Canyon boundaries,” said Dr. David Walters, USGS research ecologist and lead author of the study.
David Uberuaga, superintendent of Grand Canyon National Park, added, “studies like this continue to educate the public and highlight the threats that face the park and its resources."
…[/font][/font]
