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.
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.
The good news is that mercury concentrations are declining in American women, according to the report, which analyzed data collected between 1999 and 2004. Mercury exposure varies widely across the country because of differences in how often fish is consumed. Women along the Atlantic coast had the highest levels in their blood, followed by women living on the Pacific coast. The lowest levels were in inland areas of the Midwest and West. Those living in the Great Lakes region, the inland Northeast and the inland South were in the middle.
“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. Mahaffey and her colleagues reported that the higher mercury levels in Northeastern women reflect their more frequent fish and shellfish consumption. But they theorize that it also could mean that some of the fish they are eating are more highly contaminated than fish eaten elsewhere.
In addition, women who are more affluent, with family incomes exceeding $75,000, and women of Asian or island ethnicity had the highest mercury levels.
The study is at: http://www.ehponline.org/members/2008/11674/11674.pdf