Consumer groups want tuna, one of the most commonly consumed fish, added to the list. Seafood, a low-fat source of protein, can be an important part of a balanced diet for pregnant women and women who may become pregnant, the FDA said. Those women could eat up to 340g a week of shellfish, canned fish, smaller ocean fish or farm-raised fish.
Mercury enters the environment naturally and through industrial pollution.
Nearly all fish contain trace amounts of methyl mercury, but longer-lived, larger fish that feed on others accumulate the highest amounts of methyl mercury and pose the biggest threat.