Mercury Pollution

Mercury pollution is in our air, land and water and is a serious threat to the environment and our health. It comes from a variety of sources such as mercury in products, but the largest source in Wisconsin is emissions from coal-burning power plants.

Exposure to mercury pollution can result in many negative health effects. This is true even at low levels, especially for pregnant women and children.

In Wisconsin, high levels of mercury in the environment threaten the health of both wildlife and people. In fact, mercury pollution is so widespread in Wisconsin that every water body in the state is under a fish consumption advisory that limits how much fish people should eat.[1]

For the latest guidelines and information on these fish consumption advisories, see the Wisconsin Department of Health Services webpage “Eating Safe Fish.”

Key Points

  • The EPA estimates that more than 300,000 newborns each year are at risk of increased learning disabilities due to exposure to methylmercury.[2]
  • Coal-fired power plants are the largest single source of mercury air pollution in Wisconsin, accounting for about 40 percent of all mercury air pollution in the state annually.[3]
  • Fishing is a key industry in Wisconsin, bringing $2.75 billion in tourism revenue to our state every year and supporting over 30,000 jobs.[4]
  •  Wisconsinites must consider their health when eating fish from Wisconsin waters; it is not uncommon to find mercury concentrations of 3 ng/L to 5 ng/L in Wisconsin lakes or rivers, more than two times the 1.3 ng/L water quality criterion.[5]
Clean Wisconsin's Work

For many years, Clean Wisconsin has worked to eliminate mercury pollution by reducing emissions from coal-fired power plants, promoting proper recycling of mercury-containing products and eliminating the unnecessary use of mercury in products. Clean Wisconsin worked with sport fishing organizations and drafted a petition to the Department of Natural Resources that led to Wisconsin being just the second state in the nation to regulate mercury emissions from coal-burning power plants.

Clean Wisconsin also works to reduce mercury pollution by taking on other sources of this dangerous toxin. We worked with state legislators to enact the Mercury Products Bill, a law that bans the sale of all unnecessary products that contain mercury. We also successfully advocated for the Electronic Waste (E-Waste) Law, which requires electronics producers to offer convenient sites for recycling electronic waste like old computers, printers and similar products that contain numerous toxic substances, including mercury. All these victories have significantly contributed to the reduction of mercury pollution in our state and our waters.

Related Topic Pages

Mercury Pollution Background
This page provides an introduction to mercury and mercury pollution. It explores how mercury makes its way into the environment and its ecological effects. It also explores the toxicity of mercury and the human health effects, especially on developing children.

Mercury Emissions
The largest source of mercury in the environment is air emissions, particularly from coal-fired power plants. This page discusses air emissions of mercury, examines the 14 mercury-emitting power plants in Wisconsin, and discusses the new emissions reduction standards established in 2004 and revised in 2008.

Mercury in Products
This page provides information on the presence of mercury in products, such as thermostats, meters and switches. Improper disposal of these common household items can pose a serious problem for our health, as well as for the health of our environment. Fortunately progress has been made in eliminating mercury from products and reducing the presence of mercury containing products in places like schools and homes.  However, there is a great deal more work to be done to protect the environment and our health.


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Please cite this resource as: Clean Wisconsin, Inc. “Mercury Pollution.” Clean Wisconsin Enviropedia. Retrieved from