Do not reuse for soup or sauces. Before cooking, remove and do not eat the organs, head, skin and the dark fatty tissue along the lateral line, backbone and belly. The highest levels of chemical contaminants are found in the hepatopancreas, commonly known as the tomalley or green gland. It is the yellowish green gland under the gills. After cooking, discard the cooking water.
Fish can contain trace amounts of contaminants.
Fish sold in stores and restaurants are no exception. Consumption advice is usually not necessary for many of the popular seafood species, such as flounder, Pollock, cod, salmon, shrimp, clams and scallops, which have relatively low levels of mercury. Children under seven are advised not to eat shark or swordfish at all. In the case of PCB, dioxin and chlordane contamination, fish with lower fat content contain fewer of these contaminants, while fish with higher fat content, such as bluefish, contain higher levels. These contaminants accumulate in the fatty parts of the fish over time.