Environment
9:57 pm
Tue October 11, 2011

Research paints mixed picture on mercury levels in Great Lakes

Mercury levels in the Great Lakes have dropped over the past 40 years.

But those levels are still high enough to pose risks to humans and wildlife, especially in many inland lakes, according to a new summary of the latest research on Great Lakes mercury levels.

Researchers summarized 35 new scientific papers to get a clearer picture of mercury in the Great Lakes.

The good news: due to pollution controls, those levels continue to go down.

But researchers are finding mercury has more wide-ranging effect than they initially thought. And in some species of fish and wildlife in particular areas, it appears mercury concentrations may be on the rise.

Tim Eder, Executive Director of the Great Lakes Commission, says researchers have only recently started looking at mercury levels in birds and other wildlife that don’t eat fish.

“The more we look, the more we find. And we realize that mercury is harmful at lower levels than we previously thought.”

 “Things are going in the right direction, but we realize that the ecosystem sensitivity and the biological sensitivity to methylmercury are really, really substantial,” says James Wiener, professor at the University of Wisconsin-LaCrosse and another co-author of the study.

Wiener and other researchers presented their findings Tuesday at the start of Great Lakes Week, a four-day summit in Detroit focusing on the lakes’ environmental and economic issues.