Kids Food Safety: Fish Types Likely to be Contaminated With Toxins

The larger the fish, the more likely it is to be contaminated. Large fish live longer and, therefore, have more time to accumulate contaminants, like mercury and polychlorinated biphenyls. The Department of Health and Human Services (HHS) and the Environmental Protection Agency recommend limiting consumption of shark, tilefish, swordfish, king mackerel, albacore tuna and white tuna. These species are known to have the highest levels of mercury.

Some farmed fish have been found to have more mercury or PCBs than wild, depending on farming practices, feeds and farm location. For example, fish farms located near agricultural areas may be at greater risk due to contaminated runoff. The problem for consumers is that, at the time of purchase, they don't know whether a given fish was farmed or wild, and whether a farmed fish is from a safe source.

To ensure that the fish you catch yourself is safe, you can check with your local EPA office for levels of mercury in lakes and streams where you might fish.