Expectant Moms, Can the Fish

From the WebMD Archives

April 12, 2001 (Washington) -- Watchdog groups today filleted up the FDA's fish eating recommendations for pregnant women, offering their own more rigorous standards to minimize the risk of mercury exposure.

Methylmercury is a toxic form of mercury that gathers in fish tissue. Absorbed by the fish from pollution and from other water creatures, it poses health threats to developing brains and nervous systems of unborn babies.

In January, the FDA recommended that pregnant women avoid shark, swordfish, king mackerel, and tilefish, or ocean whitefish. The agency said these four were the most risky, since they're relatively large and long-lived fish that can carry large amounts of the poison. For other cooked fish, the agency said that women could safely eat about two large servings, or 12 oz, per week.

"What we have emphasized is to avoid these four species and then eat up to 12 oz per week of a variety of different fish, whether it be fish sticks or tuna or whatever," an FDA spokesperson, who asked not to be named, tells WebMD.

But today's report from the Environmental Working Group and U.S. Public Interest Research Group claimed that these guidelines "could expose more than one-fourth of all pregnancies (one million babies) to a potentially harmful dose of methylmercury for at least one month during pregnancy."

Want to chat with other expectant mothers? Check out our Already Pregnant message board.

According to the FDA spokesperson, "We haven't thoroughly reviewed the report, but I'm not sure how they got the numbers, and we certainly didn't get those kinds of numbers.

"We're standing by our advisory as the best public health information that we have at this time, until we see some more data that show that there is some danger to the development of individuals."

In addition to those fish already cited by the FDA, the groups recommend that pregnant women avoid nine others: tuna steaks, sea bass, Gulf Coast oysters, marlin, halibut, pike, walleye, white croaker -- also known as the Pacific croaker -- and largemouth bass.

Walleye and largemouth bass are not widely available retail fish, but sports fish that are largely recreationally caught, notes the FDA.

According to the report, "The odds are greater than one in 1,000 that consumption of a single meal of these fish will expose the fetus to a potentially hazardous amount of methylmercury for longer than 30 days."

The groups also recommend that pregnant women eat no more than one serving per month of the following fish: canned tuna, mahi mahi, blue mussel, Eastern oyster, cod, Pollock, Great Lakes salmon, Gulf Coast blue crab, wild Channel catfish, and lake whitefish.

Safe, low-mercury fish options for pregnant women include farm-raised trout, farm-raised catfish, shrimp, fish sticks, summer flounder, wild Pacific salmon, croaker -- also known as the Atlantic croaker -- mid-Atlantic blue crab, and haddock.

The groups report was based on nearly 60,000 mercury tests on fish from a range of government agencies. And they used a tougher mercury safety standard than the one the FDA deems acceptable. They also claimed that the FDA's January bulletin recommendations to women were based on mercury levels measured in 1979, even though the toxin has since become more widespread.

According to the report, the FDA's mercury standards are designed to protect an average adult -- not a pregnant woman or her baby. Last month, the CDC reported that 10% of women of childbearing age already had high mercury levels. The report also complained that the FDA doesn't require seafood companies to test for mercury in fish.

In January, the General Accounting Office criticized the laxness of the FDA's seafood safety program.

But the National Food Processor Association says the new mercury report is a bit of a fish story.

In a statement today, the group said that the FDA was "a more credible source of advice and information on health and safety issues." It claimed that many health experts "worry that Americans do not eat enough seafood and have expressed concern that mercury 'warnings' might frighten people away from fish that can be an important part of a healthful diet."