The U.S. government plans to warn women of childbearing age to limit their consumption of tuna because of concerns about mercury poisoning, The Washington Post reported on Thursday.
A draft advisory from the Food and Drug Administration and the Environmental Protection Agency cautions pregnant women, nursing mothers, young children and women of childbearing age to limit their intake of tuna and other fish and shellfish to 12 ounces a week, the Post said.
The FDA has previously warned pregnant women against eating shark, swordfish, king mackerel and tilefish because of their high levels of mercury, but had not included tuna on that list because it feared women would substitute it with less nutritious food.
Among seafood, tuna ranks second only to shrimp in popularity in the United States.
The advisory says mercury levels in tuna can vary: fresh tuna steaks, for example, have higher mercury levels than canned light tuna, the Post said. Women can safely eat tuna on a weekly basis, but those at risk should eat no more than six ounces a week, an FDA official told the paper.