OTTAWA (CP) -- Mounting evidence that mercury contamination can damage fetal brain development has pushed Health Canada to review its guidelines on fish consumption by women of childbearing age, The Canadian Press has learned. The review comes amid mounting international concern about mercury, with U.S. authorities adopting guidelines for fish consumption that are far stricter than their Canadian counterparts.
Mercury is a toxin spewed by coal-burning power plants, and released by some consumer products. It accumulates in living things and becomes concentrated at higher levels of the food chain, especially in larger fish. Studies over the last decade suggest that even low levels of mercury in a mother's blood or breast milk can affect the developing brain of her child, leading to learning disabilities and lower intelligence.
Earlier this year, the U.S. Food and Drug Administration issued a directive warning women of childbearing age to eat no more than two meals or 12 ounces of seafood, including canned tuna, weekly.
That directive was based in part on the work of a U.S. Environmental Protection Agency biochemist, Kathryn Mahaffey, who estimates that one in six pregnant women in the United States had high enough blood mercury to damage her child, for a total of 630,000 U.S. newborns at risk. "We have groups in the United States, in some of our urban areas, whose exposure is every bit as high as in the Inuit populations" in Canada's north, said Mahaffey. "Even though the Inuit eat a lot of fish, so do some of our urban consumers."
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