"Legacy contaminants are decreasing more quickly than previously reported in three of the Great Lakes, but have stayed virtually the same in two other lakes, according to new research."
"'These are very positive results. The lakes are improving and slowly cleaning themselves up,' said Thomas Holsen, co-director of Clarkston University’s Center for the Environment. Even with the decreases, it will be 20 to 30 years until the decades-old contaminants in Great Lakes fish decline to the point that fish consumption advisories can be eliminated. Banned in the 1970s, PCBs, DDT and other banned compounds dropped about 50 percent in fish in Lakes Michigan, Ontario and Huron from 1999 through 2009, although there were no significant changes in Lakes Superior and Erie fish, according to the new study. In all of the lakes, the older contaminants are being replaced by newer ones, mostly flame retardants, that are building up in fish and wildlife."