Eat smaller fish Some chemicals can build up in fish with age. The larger the fish, the higher the levels of chemicals they may contain, within the same species. It's always fun to catch large fish, but it's safer to eat smaller ones. If you keep large fish, freeze some of the fish and eat smaller meals spaced out over time. The fillet portions of fish are the safest parts to eat.
Chemicals tend to be much higher in the guts and liver of fish.
Do not eat these parts and do not use them to make sauces, stock or chowder. Trim away fat Many chemicals, including DDT, PCBs and dioxins, are stored in the fat. You can reduce your exposure to these chemicals by trimming fatty areas. Also, skin the fish to remove the thin layer of fat under the skin. Cook so that fat drips off Bake, broil, steam, or grill fish on a rack so that the juices from the fat drip off during cooking.