FDA and EPA Clash over Mercury in Fish

The Washington Post obtained a copy of a draft report on mercury that Food and Drug Administration sent to the White House Office of Management and Budget, and reports that it contains advice that alarms scientists from the Environmental Protection Agency. At issue is advice about fish consumption for women of child-bearing age, pregnant women, nursing mothers, and young children. All of these groups can benefit from fish’s omega-3s, but the mercury that contaminates many fish can interfere with neurological development in fetuses and young children.

FDA regulates mercury in commercially available seafood, while EPA is responsible for mercury in fish caught recreationally. In 2004, the two agencies released a joint advisory aimed at these sensitive groups. They advised avoiding consumption of four kinds of fish that contain high levels of mercury (shark, swordfish, King Mackerel, Tilefish) and eating up to 12 ounces per week “of a variety of fish and shellfish that are lower in mercury.”

Now, though, it seems the FDA wants to recommend eating more than 12 ounces of fish per week, because that will deliver the greatest benefit from the nutrients contained in fish. The Washington Post’s Lyndsey Layton explains that this move does not meet with approval from EPA:

The two agencies are supposed to work together to regularly review the advisory, but EPA sources said the FDA went ahead with its own proposal earlier this year, not consulting the EPA until the document was nearly finished.

The Environmental Working Group, an advocacy organization, wrote yesterday to EPA Administrator Stephen L. Johnson and urged him to fight the FDA’s recommendations.

“This is an astonishing, irresponsible document,” said Richard Wiles, the environmental group’s executive director. “It’s a commentary on how low FDA has sunk as an agency. It was once a fierce protector of America’s health, and now it’s nothing more than a patsy for polluters.”

Kathryn Mahaffey, who was the EPA’s top mercury scientist until she left the agency in August to become a lecturer at George Washington University School of Public Health, said the FDA used an “oversimplified approach” that could increase the public’s exposure to mercury.

Kathryn Mahaffey’s name stood out for me not only because she teaches here at GW but because I know she’s the lead author of a new study on mercury concentrations in women of childbearing age, which has been published online ahead of print in Environmental Health Perspectives. Marla Cone provides a good overview of the study’s findings at Environmental Health News:

Women in the Northeast are contaminated with the highest concentrations of mercury in the United States, with one of every five exceeding levels considered safe for fetuses, according to a new national study.
 
The study, led by U.S. Environmental Protection Agency scientist Kathryn R. Mahaffey, is the first regional look at mercury concentrations in women of childbearing age  (Editors Note, 10/2/2008: Mahaffey was an EPA scientist at the time this study was written and published; she retired on Sept. 1.).

Mercury is a potent neurotoxin that accumulates in fish and seafood. When babies are exposed to high concentrations of mercury in the womb, their brains may develop abnormally, impairing learning abilities and reducing IQ.

Nationwide, one of every ten women—nearly 7 million women—exceeded the mercury concentration that may pose a risk to fetuses, according to the new report, published online in Environmental Health perspectives on Aug. 25.

Cone notes that the study found mercury concentrations in American women to be declining overall, but women near coastal areas, where fish consumption is greater, are at increased risk for having higher-than-acceptable levels of mercury:

“Women living near the coastal areas have approximately three to four times greater risk of exceeding acceptable levels of mercury exposure than do non-coastal dwelling women,” the authors wrote.

Some were very highly exposed. Five percent of women along the Atlantic coast had levels that were more than three times the amount that may harm a fetus.

Check out the map accompanying the EHN piece for an illustration of just how stark the regional differences are.

The study’s authors propose that the overall reduction in mercury levels comes not from a drop in total fish consumption but from “a more discerning series of choices in type of fish eaten.” It seems that the 2004 advisory and educational efforts by the media and health educators have succeeded to some degree, but either haven’t reached all of the women of child-bearing age or aren’t sufficient for women living in certain geographical areas. Mahaffey and her colleagues suggest that geographic variations in mercury levels might be due in part to higher mercury concentrations in fish that are both caught and consumed in the Northeast.

It seems that the appropriate response to this finding would be to figure out why women in coastal areas are more likely to have unacceptable mercury levels, and amend the advisory to address the causes that are uncovered. The EPA’s analysis suggests that women are, in fact, able to follow advice about altering their eating habits in response to the mercury advisory. Perhaps FDA should work with EPA to see if further alterations to the advisory could address the two goals of increasing consumption of beneficial fish and lowering mercury levels in the areas where they are too high.

To simply encourage women of childbearing age to eat more fish, though, is to risk increasing the percentage of women whose mercury levels are high enough to pose dangers to their future children’s neurological development.

Comments

  1. #1 Brenda Afzal, RN, MS
    December 16, 2008

    So help me understand, the public health messaging that seeks to protect the fetus from exposure to a known neurological toxin has been successful in parts of the nation and now the FDA would like to change that message to a less protective one? A 2007 study, by Wendy McKelvey et al, reported in Environmental Health Perspectives, indicated that “Higher than national blood mercury exposure in NYC adults indicates a need to educate New Yorkers about how to choose fish and seafood to maximize health benefits while minimizing potential risks from exposure to mercury.” The authors concluded that that frequency of consumption explained some of the elevation in Asians and other subgroups.

    We should be spending our efforts on reducing the causes of mercury contamination, not in confusing the public with mixed messages.

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