Lakes and Mercury
Wisconsin is ready to cut mercury emissions at power plants. At issue is the link between smokestack emissions and mercury found in fish. If approved when legislation comes before the Natural Resources Board in the fall, the regulations would restrict mercury emissions from coal-fired power plants 90% by 2020.
The measure would have big repercussions in a state where 70% of the electricity is generated from coal. Similar restrictions are being advanced in other states and by the federal government. In 2003, the Department of Natural Resources estimated that reducing mercury emissions by 80% could cost consumers $18 to $21 a year. Since then, technology has improved. But demand for equipment is growing.
In 2001, Wisconsin upgraded its fish advisory from specific lakes to a statewide warning that urges consumers to limit consumption of fish such as walleye or northern that tend to have higher levels of mercury.
Zooplankton receives methylmercury almost immediately from their environment. Small fish then eat the zooplankton, and as methylmercury moves into larger species, concentrations get higher, making fish such as walleye, northern and muskellunge potentially less safe than bluegill or crappie.
The five fish with the highest mercury levels in the commercial seafood market are swordfish, shark, American lobster, halibut and sable fish.
July 23, 2007 6:55 AM | Category: Chemicals