July 26, 2011
MADISON -- Wisconsin's commitment to cleaning up contaminated sediment and regulating mercury is paying off for anglers, as recent studies and the newly available 2011 fish consumption advice booklet show reduced contaminant levels in fish in some waters.
"The data we've collected over the past 40 years shows general improvements in mercury and PCB levels in many locations," said Candy Schrank, Department of Natural Resources fisheries toxicologist. "Studies using our data support assertions that fish respond to sediment clean-up and mercury emission reductions, and this is good news for anglers and for state and local economies."
Nearly half of Wisconsin adults say they fish, and sport fishing generates a $2.75 billion annual economic impact in Wisconsin, supports 30,000 jobs, and generates $200 million in state and local tax revenues.
DNR has been working for more than a decade with local communities to reduce the use of mercury-containing products, promote mercury recycling, reduce mercury spills and reduce air emissions from coal-fired power plants and other industrial sources.
Fish are the main source of mercury and PCBs in the human diet; both contaminants can harm developing fetuses and children and are also harmful for adults, Schrank says.
Mercury is naturally occurring in the environment and also comes from human sources. It enters waters and is converted to a toxic form that's easily absorbed by fish and other aquatic organisms, and in turn, by people that eat the fish. PCBs are man-made chemicals once used in a variety of manufacturing processes but now banned; they remain in sediments and accumulate in fish and other organisms.
Several big reduction efforts took effect in 2010: utilities were required to reduce mercury emissions by 40 percent by Jan. 1, 2010; ERCO Worldwide, which owns and operates a chlor-alkali plant in Port Edwards that until 2009 was responsible for about 20 percent of the annual mercury emissions reported in Wisconsin, voluntarily moved to a new technology that eliminated mercury emissions from its manufacturing processes and a new law effective Nov. 1, 2010, bans the sale of mercury containing devices including fever thermometers, barometers, toys and thermostats, according to Martin Burkholder, lead staff on mercury for the air management program.
Wisconsin and the federal government have worked with a variety of responsible parties, committing significant resources toward removing PCB-contaminated sediments from rivers and harbors that historically received wastewater discharges from paper mills and other operations that used PCBs.
In March 2011, Gov. Scott Walker travelled to Little Lake Butte des Morts to announce that successful remediation had reduced PCBs in walleye (pdf), sediment and water significantly to levels that would have taken 15 to 20 years to achieve if nothing had been done.
Other stretches of the Lower Fox where remediation efforts are ongoing, or have been planned but not yet started, still carry advice ranging from "don't eat" to "limit to one meal per month" depending on the species.
"What we're doing is working and we need to keep at it until all of our waters are fishable and swimmable," says Ken Johnson, DNR's top water official.
FOR MORE INFORMATION CONTACT: Candy Schrank (608) 267-7614; Marty Burkholder (608) 264-8855