More Information on Fish Contaminants

Background information and resources on fish contaminants and consumption.

Advice for our Hmong and Spanish Anglers

• Eating Safe Fish [exit DNR] - more information on fish consumption advice including other languages from Wisconsin's Department of Health Services.
• Eat Safer Fish in Wisconsin (Noj ntses huv hauv xeev Wisconsin) video - preview or purchase the complete version
• Hmong family guide [exit DNR]
• Spanish family guide [exit DNR]

More Detailed Information

• FDA Consumer Advisory [exit DNR] for pregnant women and women of childbearing years who may become pregnant about the risks of mercury in fish (seafood) from the U.S. Food and Drug Administration.
• Mercury in the Environment describes how the Wisconsin Department of Natural Resources is working to reduce mercury in our environment.
• Toxicological Effects of Methylmercury [exit DNR] is a report from the National Academies' National Research Council.
• Human Health and Environmental Resources [exit DNR] - from Wisconsin's Department of Health Services.
• U.S. Environmental Protection Agency's Websites:
  • Mercury Information [exit DNR]
  • National Advisory Information [exit DNR]
• PCBs in Green Bay white perch
• 1990-2005 Statewide Mercury Summary [PDF 80KB]
• Mercury in walleye 1982-2005 [exit DNR]
• Wisconsin case histories of mercury exposure [exit DNR]
• Mercury in Selected Fish Species over Time [PDF 569KB]
• Assessment of methylmercury exposure in Wisconsin (hair study) [exit DNR]

Statewide General Advice

As a result, most - but not all - inland waters carry the same statewide advice for how many meals of fish people can safely eat while reducing their risk of exposure to mercury. There are different recommendations for sensitive populations [includes women of child-bearing age, pregnant women, and young children] and for all other individuals. Wisconsin's new statewide advice or safe eating guidelines apply to most of Wisconsin's inland (non-Great Lakes) waters.

The changes in mercury advice result from the National Research Council's report, "Toxicological Effects of Methylmercury" (2002). This report concluded that the standard the U.S. Environmental Protection Agency's (EPA) reference dose is appropriate to determine whether to issue consumption advice for fish. A reference dose is defined as "an estimate of a daily exposure to the human population (including sensitive subpopulations) that is likely to be without a risk of adverse effects when experienced over a lifetime."

The use of this new reference dose required that consumption advice be issued, ranging from "1 meal per week" to "do not eat" for most species of fish. Most of Wisconsin's fish contain at least that amount based on statewide testing. Mercury concentrations vary between species or different types of fish. Thus, different levels of consumption advice is appropriate for most waters and varies with the species of fish and the person eating the fish.

The National Research Council also concluded that developing fetuses are by far the group most at risk from mercury because of the sensitivity of their developing nervous system. Scientists estimated that 60,000 children born each year in the United States are at risk for neurological and learning problems because their mothers ate large amounts of mercury-contaminated fish and seafood during their pregnancy.