The deadliest catch: Can you eat Chicago river fish?

By Elizabeth Czapski | Staff Writer

With summer comes fishing and in the Chicago River, the fish are biting. But should people be eating them? Well, it depends on the type of fish.

According to the Illinois Department of Public Health, fish in Illinois waterways can be contaminated with several chemicals, but in the Chicago River, polychlorinated biphenyls (PCBs) are the most common contaminant. This group of man-made chemicals was used in manufacturing until it was banned by the Environmental Protection Agency in 1979.

PBCs are known as legacy contaminants that stay in the environment for a long time, according to Dr. Timothy Hoellein, Associate Professor of Biology at Loyola University Chicago. Once an organism consumes these contaminants, the PCBs remain in the tissue of living organisms and can be passed up the food chain to humans.

The Department of Public Health’s fish advisory states that there is “no immediate health threat from eating contaminated fish.” The key word there is immediate because long-term low-level exposure may be harmful and could cause developmental problems in children.

The Department of Public Health recommends limiting consumption of certain species. Channel catfish that are 18 inches or longer should be limited to once per month. For largemouth bass and sunfish of all sizes, the recommendation is one meal per week. Common carp smaller than 12 inches should be limited to six meals per year, and carp longer than 12 inches should not be eaten at all. All of these species are contaminated with PCBs.

According to Melaney Arnold, public information officer at the Illinois Department of Public Health, the larger the fish, the longer it has been consuming contaminants, which leads to a higher build-up of chemicals in the fish.

The bottom line is, just because you’re hooked on fishing, don’t get hooked on eating everything you catch.

Published August 2, 2018