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As snowstorms sweep the East Coast of the United States this week, transportation officials have deployed a go-to solution for keeping winter roads clear: salt. From a report: But while pouring tons of salt on roads makes winter driving safer, it also has damaging environmental and health consequences, according to a growing body of research. As snow and ice melt on roads, the salt washes into soil, lakes and streams, in some cases contaminating drinking water reservoirs and wells. It has killed or endangered wildlife in freshwater ecosystems, with high chloride levels toxic to fish, bugs and amphibians, according to the Environmental Protection Agency. “It’s an issue that requires attention now,” said Bill Hintz, an assistant professor in the environmental sciences department at the University of Toledo and the lead author of a recent research review published in the journal Frontiers in Ecology and the Environment.

“There’s plenty of scientific evidence to suggest that freshwater ecosystems are being contaminated by salt from the use of things like road salt beyond the concentration which is safe for freshwater organisms and for human consumption,” Dr. Hintz said. Salt has been used to de-ice roads in the United States since the 1930s, and its use across the country has tripled in the past 50 years, Dr. Hintz said. More than 20 million metric tons of salt are poured on U.S. roads each winter, according to an estimate by the Cary Institute of Ecosystem Studies in New York, and the environmental costs are growing. Still, little has been done to address the environmental impact of road salt because it is cheap and effective, said Victoria Kelly, the environmental programming manager at the Cary Institute. By lowering the freezing temperature of water, salt prevents snow from turning to ice and melts ice that is already there.

Read more of this story at Slashdot.