Are Tumors in Wild Fish Harvested in the Great Lakes Region Related to Contaminants in Water Resources?

Science Center Objects

Our specialized teams of scientists are working in our laboratories and at field sites around the Great Lakes in collaboration with other federal and state resource agencies to document the prevalence of skin and liver tumors. Tumor prevalence in white suckers (Catostomus commersonii), a fish harvested as a food source by local communities, is related to the degree of urbanization in watershed.

A previously uncharacterized strain of hepatitis B virus in fish is prevalent in these white suckers. This virus is known to be associated with liver disease and tumors in other species.

Fish health is monitored in the Great Lakes region and elsewhere across the United States to evaluate if there are adverse effects of contaminant exposures on fish or the people who eat them.

Questions We're Working On:

  • Do exposures to specific contaminants or contaminant mixtures affect the immune systems of fish, making them more vulnerable to disease?
  • What are the sources of contaminants that make fish more vulnerable to disease?
  • Does the presence of tumors in white suckers indicate a potential threat to fisheries or the public?
 Lip tumor diagnosed as a papilloma on a white sucker fish

A lip tumor diagnosed as a papilloma on a white sucker (Catostomus commersonii) collected from the Milwaukee River. A lip tumor diagnosed as a papilloma on a white sucker (Catostomus commersonii) collected from the Milwaukee River. (Credit: Vicki S. Blazer, USGS, and Brenda Ferris, University of Wisconsin.  Public Domain.)