A government test of fish pulled from nearly 300 streams in the USA found every one of them contaminated with some level of mercury.
The U.S. Geological Survey’s research marks its most comprehensive examination of mercury contamination in stream fish. The study found that 27% of the fish had mercury levels high enough to exceed what the Environmental Protection Agency considers safe for the average fish eater, those who eat fish twice a week.
But the findings in wild-caught fish underscore how widespread mercury contamination in the nation’s waterways has become. Previous research has found levels of concern in ocean and lake fish.