BELTSVILLE, Md. -- Pregnant women are urged not to eat four types of fish that could contain enough mercury to hurt an unborn baby's developing brain. But should tuna or other species be on the do-not-eat list?
The Food and Drug Administration says a few servings a week of most fish is safe. But critics charge the FDA watered down its tuna advice after seafood industry lobbying -- and should have considered other worrisome fish -- and thus left tens of thousands of babies at risk of learning disabilities.
The FDA insists its advice wasn't tainted, but asked its independent scientific advisers to judge whether it erred and if American women need stronger fish warnings.
"It was our genuine belief that if women consciously followed this advice ... these women would be protecting their unborn children," FDA food safety chief Joseph Levitt said Tuesday as the advisers opened the three-day inquiry, an inquiry taken so seriously that FDA acting commissioner Lester Crawford attended.
"It is an emotionally charged issue," Levitt acknowledged. "We are truly open and want your best advice, whether you agree with us or not."
The panel will issue a decision on Thursday.
Fish is very nutritious; certain types contain high levels of heart-healthy fats, plus fats important for fetal brain development. But different types also harbor different amounts of toxic mercury. Typically, the largest fish contain the most mercury.
Based on loose figures about U.S. fish consumption, some 60,000 newborns a year might be at risk of neurologic damage because of mercury their mothers absorbed during pregnancy, the National Academy of Sciences says.
About 8 percent of U.S. women of childbearing age have enough mercury in their blood, based on the academy's levels, to be at risk, says the Centers for Disease Control and Prevention. Those who eat three or more servings of fish a week had the highest levels.
Last year, the FDA advised:
--Pregnant women, and those wishing to become pregnant, should not eat shark, swordfish, king mackerel or tilefish (also called golden snapper) because they contain high mercury levels.
--Those women can safely eat up to 12 ounces of any other cooked fish a week -- from canned tuna to shellfish to smaller ocean fish.
Critics immediately attacked the FDA for not including tuna steaks, which contain somewhat less mercury than swordfish.
Some groups also urge pregnant women to curtail canned tuna consumption, although canned tuna is made from small tuna fish that contain far less mercury. And some advise pregnant women to avoid other species, such as sea bass and marlin.
The result is mass confusion -- women don't know what to believe, consumer advocate Caroline Smith DeWaal of the Center for Science in the Public Interest told the FDA advisory panel.
Worse, she said, the FDA doesn't prevent the most heavily contaminated fish from being sold. Nor does it require warning labels on the fish pregnant women aren't supposed to eat, making it difficult for consumers to know the advice.
"It truly is a toothless tiger," she said.
Another advocacy organization, the Environmental Working Group, says it created a model of what would happen if pregnant women followed FDA's advice, and concluded that up to 1 million a year could be exposed to worrisome mercury levels.
The FDA strongly disagrees, saying it can't validate the activists' model.
A seafood industry consultant argued Tuesday that the risk has been inflated mostly because women eat far less fish than has been estimated.
The FDA deems fish safe if they contain less than 1 part per million of methylmercury; the four types on its do-not-eat list exceed that level. Critics charge large tuna steaks can contain more, too, and certain other species contain only slightly less.
One of FDA's own advisers said Tuesday that he bought 11 cans of tuna fish at his grocery store, and independent testing showed one of them contained 1.2 ppm of mercury.
How much mercury exposure is too much is controversial. There are two competing studies:
--Babies born in the Faroe Islands in the North Atlantic, where people eat lots of highly contaminated whale meat, have a higher risk of certain defects in memory and learning.
--Babies in the Indian Ocean's Seychelles Islands seem to suffer little effect. Women there eat mostly the same fish Americans do, but so much that their bodies contain 10 to 20 times more mercury than Americans'.
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