Mercury Found In Fish Living In Pristine Lakes

Federal researchers have found mercury in all fish tested from remote lakes and streams in 21 national parks in 10 western states, but the mercury levels in most of the fish were below the threshold for potential health effects in fish, birds, and humans. The study was conducted by the National Park Service and the U.S. Geological Survey from 2008 to 2012. More than 1,400 fish, including brook, rainbow, and lake trout, from 86 lakes and rivers were tested. Smaller fish consumed by wildlife were also sampled. Mercury levels varied greatly from park to park and within each park. Grand Teton and Great Basin National Parks had the lowest percentage of fish exceeding the threshold for unlimited human consumption, and Glacier National Park had the highest, with 100% of its fish exceeding that threshold.