October 13, 2011
New research on mercury levels in the Great Lakes shows walleye and other fish that people eat contain more of the toxin than previously thought. The study says there has been a general decline in mercury levels over the past four decades but the current levels are higher than recommended for eating certain fish.
The three-year study released by the Great Lakes Commission found 6 of the 15 most commonly eaten sport fish had mercury levels higher than recommended for consumption. Mercury is a pollutant that poses hazards to the unborn and the brain development of young children. At high enough levels it can be lethal to wildlife and at lower levels can harm the reproductive systems of loons and bald eagles.
Atmospheric emissions are the primary source of mercury deposits in the Great Lake basin. Regulations have led to a 20 percent reduction in emissions and the study says further controls on are expected to lower mercury concentrations.