Scientists have found mercury in fish caught in some of the most remote water bodies of the West. Mercury is a neurotoxin that is especially harmful to pregnant women and children.
A new study looked at mercury levels in fish sampled from 21 national parks around the West.
Scientists with the U.S. Geological Survey and the National Park Service tested more than 1,400 fish – mainly sport fish like brook, cutthroat and rainbow trout – from Utah to Alaska.
They found mercury in every single fish.
So, how did it get there?
Mercury gets into the atmosphere from volcanic eruptions and the burning of fossil fuels. The particles can travel thousands of miles and then come down in rain and snow, eventually making their way into the food chain.
But it’s not all bad news, says Collin Eagles-Smith. He’s a research ecologist with the U.S. Geological Survey and lead author of the study. Of the fish the scientists tested, 96 percent were within safe levels for human consumption.
"The concern is that there were some areas, and some fish, that did have concentrations that might pose a threat to either wildlife or humans," Eagles-Smith said.
Fish in Olympic National Park had a higher average mercury concentration than other parks in the Northwest, but none of those fish exceeded safe levels.
Things were different in Mt. Rainier National Park, where scientists found that two percent of the sport fish they sampled wouldn’t be considered safe for human consumption, under federal standards.
Fish caught in Crater Lake in Oregon had some of the lowest levels in the Northwest.
Fish in Alaska and Utah had the highest in the study.
Copyright 2014 KUOW