News Coverage
Obstetrics:
FDA uner fire for mercury in fish advice
Published January 1, 2004
Consumer advocates are again urging the government to advise pregnant women to limit tuna consumption, arguing that some varieties contain more potentially harmful mercury than others.
But the U.S. Food and Drug Administration (FDA), which plans in spring 2004 to issue new consumer advice on mercury in fish, says stronger warnings are not needed.
Fish, including tuna, is very nutritious. Many species contain omega-3 fats that are very heart-healthy and important for fetal brain development. The American Heart Association recommends eating fish twice a week.
But fish also can harbor mercury, a metal that accumulates in the bodies of fish-eaters and can damage the growing brains of fetuses and young children. About 8% of U.S. women of childbearing age have enough mercury in their blood to put a fetus at risk.
Some fish varieties harbor more mercury than others. The FDA has long told women who may become pregnant to avoid shark, swordfish, king mackerel, and tilefish. But the FDA in 2001 said a few servings a week - totaling 12 ounces - of any other fish is healthy during pregnancy. That sparked fierce criticism from consumer advocates who argue that tuna, with moderately high mercury levels, is eaten so often by pregnant women and young children that it needed warnings, too.
In 2002, the FDA's own advisers recommended saying that two 6-ounce cans of tuna a week is fine if that's the only fish pregnant women eat; a single can is okay if they eat other fish, the agency said.
The FDA released its new fish testing data on December 9, 2003, showing that more expensive white, or albacore, canned tuna contains almost three times as much mercury than cheaper "light" canned tuna.
Drafts of new consumer advice the agency is planning don't spell out that difference - or heed the 2002 recommendation. Instead, the FDA plans to tell pregnant women that mercury levels in tuna vary and that tuna steaks and canned albacore "generally contain higher levels of mercury than canned light tuna." The new advice also stresses eating a variety of fish, not the same type more than once a week, said David Acheson, MD, the FDA's medical officer in charge of the issue. But it doesn't single out limits for tuna.
"We believe that if people follow what's written in the advisory, there will be a significant level of protection," Acheson said.
That doesn't go far enough, consumer advocates plan to tell the FDA's advisers. "They've completely failed in their obligation to protect the public," said Richard Wiles of the Environmental Working Group, which plans a legal challenge if the FDA doesn't change its position. He said a single 6-ounce can of albacore a week could put many women, depending on their size, over the safe mercury limit.
Mercury accumulates in fish over time; canned light tuna comes from small fish, albacore and steaks from large ones.
Eleven states already tell pregnant women to limit consumption of canned tuna, and Rhode Island, in summer 2003, told them to avoid albacore, said Michael Bender of the Mercury Policy Project.
Nobody actually knows how much tuna or other mercury-containing fish pregnant women and young children eat today. But in 2002 tuna slipped from the most-eaten seafood to second place, replaced by shrimp.
Even though albacore has more mercury than light tuna, it still contains levels well below the FDA's safe limits, stressed Dave Burney of the U.S. Tuna Foundation. "Albacore tuna happens to have more omega-3 in it than any other fish," he said. "Any advice for women to not eat fish is the wrong message to send."
But the Consumers Union is urging the FDA to rewrite its advice and tell consumers what the lowest-mercury options are - such as crab, catfish, flounder, salmon, and shrimp - instead of focusing just on what to avoid. "The message should be, 'Eat more fish for your health while minimizing your mercury intake,'" said Consumers Union scientist Edward Groth.
Also, parents need to know how much fish is safe for young children, he said. The FDA's planned advice just says they should eat less than adults.
Tuna aside, the FDA's draft advice does warn that fish caught from local lakes and rivers often contains more mercury than commercial fish, so heed local warnings on which freshwater fish to avoid. If there is no advice for your area, eat no more than 6 ounces of locally caught fish a week, the draft says.
This article was prepared by Women's Health Weekly editors from staff and other reports.