Great Lakes fish advisories show rising pollution

Toronto, Canada (GLOBE-Net) - Levels of toxic chemicals in Great Lakes fish are alarmingly high and becoming more serious over time, says a new report from Environmental Defence. Tougher regulations and a plan from federal and provincial governments is needed to cleanup the lakes, says the group.

The report, Up to the Gills: Pollution in Great Lakes Fish, analyzed the fish advisories published by the Ontario Ministry of the Environment for four species of fish in 13 locations across the Great Lakes. It found that many categories of fish are somewhat or completely unfit for human consumption, and that other categories of fish are becoming so.

The major chemical contaminants that cause consumption advisories include mercury, PCBs, pesticides, dioxins and furans. Health effects of these chemicals include damage to the nervous, respiratory and immune system, as well as cancer.

The report identifies a few regions, such as Lake Erie, which have shown some reductions in toxic contamination levels over time, but adds that a greater number of areas are becoming more polluted. In Lake Ontario, for example, eight categories of fish became more contaminated between 2005 and 2007, while only one category improved.

Typically, advisory levels are more severe for larger fish, which are generally older and have therefore accumulated more toxins in their tissue. But severe consumption advisories have been issued for even small sizes of fish in Lake Ontario.

More than five million anglers fish the Great Lakes every year in a commercial and sport fishing industry worth $3.5 billion a year. While the report highlights the benefits of fish in a healthy balanced diet, it does caution consumers to watch what kinds of fish they eat and from where.

The report makes several recommendations on how to protect public health by:

  • improving the information used in fish advisories;
  • enhancing the delivery of fish advisories to high risk groups;
  • preventing fish contamination advisories by reducing pollution from industry, sewage systems, agriculture and urban runoff; and
  • enhancing the Canada-U.S. response to threats to fish in the Great Lakes.

“To reduce threats to human and ecological health, we must insist on aggressive measures to prevent the movement of toxic chemicals into fish and equally aggressive measures to revitalize the Great Lakes basin ecosystem,” said Dr. Gail Krantzberg, director of the Centre for Engineering and Public Policy, and a professor at McMaster University in Hamilton, Ontario specializing in Great Lakes protection and remediation.

The report is available to download at It includes a detailed map of fish consumption advisories over time in various regions across the Great Lakes.

For More Information: Environmental Defence

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