Mercury Levels in Great Lakes Fish Between 1970s and 2007

ACS Abstract:
A number of initiatives have curtailed anthropogenic mercury emissions in North America over the last two decades; however, various factors, including long-range transport of global emissions, may complicate the response of fish mercury levels to remedial actions.

Since the Great Lakes of North America are together the largest surface freshwater body in the world and are under the influence of many complicating factors, trends of mercury in fish from the Great Lakes can reflect the overall impact of mercury management actions at local, regional, and perhaps global scales.

The concentrations have generally declined over the three decades (mid-1970s to 2007);

Please read on at American Chemical Society