If you want to furrow a few eyebrows, tell your friends about the two-headed baby trout born of wild fish caught in a polluted Idaho stream (above). If you want to get them really riled up, explain that a major mining company linked this disturbing mutation to selenium pollution from one of its own mines -- and still had the audacity to assert that those selenium levels are safe.
The questionable integrity of this company's scientific research, which Leslie Kaufman detailed last week in The New York Times, has fueled a much broader debate over what levels of selenium pollution should be allowed in U.S. watersheds. Federal agencies, environmental groups and one of the nation’s largest private companies are at odds, and Kaufman’s portrayal of the details is both intriguing and disturbing.
“In my research, I have seen lots of malformed baby fish, but never one with two heads,” David Janz, an aquatic toxicology professor at the University of Saskatchewan, told Kaufman. “Selenium is emerging as a pollutant of global concern,” he said. “We need to be careful here.”
As is the case with many essential nutrients, the dose makes the poison: Too much selenium can trigger hair and fingernail loss in people, as well as and numbness in fingers and toes (which is why it has been regulated in drinking water since the 1970s). It is even more dangerous for aquatic, egg-laying animals. Kaufman cites an incident in California in the early 1980s when excessive selenium in agricultural runoff plagued waterfowl with grotesque birth defects, including missing eyes and protruding brains.
So, how much is too much? The mining company at the center of the current controversy, J.R. Simplot Company, has asked the Environmental Protection Agency for special permission to allow selenium in creeks near its Smoky Canyon Phosphate Mine to remain at current levels, even though the concentration of that element in at least one local waterway is 70 parts per billion: 14 times higher than the federal limit. (And that’s apparently after a $3.5-million clean-up effort.)
Read more at Discovery News
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