Mercury in Fish Not Dangerous, Study Shows

Published December 1, 2005

New data gathered from 700 children who were exposed to nearly unprecedented levels of mercury while in their mothers’ wombs show the extremely heightened levels of mercury have caused no medical problems.

Children ‘Picture of Health’

For the past 15 years, scientists have been following the 700 children on the tiny island nation of Seychelles, Africa, whose mothers ate tremendous amounts of high-mercury fish while pregnant. All the mothers ate high-mercury fish daily, resulting in blood mercury levels six times higher than those of U.S. women.

Every few years, scientists from the University of Rochester Medical Center test the children’s intelligence, attention span, verbal skills, memory, motor skills, reasoning ability, and other cognitive abilities. Results from the latest round of testing were released September 26.

According to the most recent findings, the mercury-exposed children “continue to be the picture of health,” according to the September 27 Rochester Democrat and Chronicle.

“These results are certainly no surprise and are consistent with the results that have been reported for more than a decade,” said Gilbert Ross, medical director at the American Council on Science and Health. “Their exposure to fish with high mercury content has so far had no negative measurable effects.”

Data Contradict Expectations

When scientists first began studying the Seychelles children, they expected to find a clear pattern of developmental defects. Real-world data, however, have shown otherwise.

“The body of evidence so far indicates that there are not detectable effects in young children,” said lead scientist Philip Davidson, as quoted in a September 19 University of Rochester news release. Scientists will continue to monitor the children to ensure negative effects do not manifest themselves later in life.

‘Hypothetical’ Risks

Importantly, the University of Rochester scientists raised the possibility that mothers who avoid fish while pregnant in response to unwarranted mercury advisories may cause their children more harm than good.

“The findings from the Seychelles have led the team to weigh the benefits of nutrition from fish against the risks of small levels of exposure to mercury,” noted the University of Rochester news release. “Is it possible that avoiding fish during pregnancy could hurt children more than any risk from mercury?”

“I would counsel the American public to not be afraid of eating fish, despite the allegations of advocate groups and some of our government agencies,” Ross advised. “These are merely hypothetical risks. In contrast, fish consumption has empirically proven to be very beneficial. Among other benefits, fish consumption helps combat heart disease, arrhythmias, and cognitive decline in old age.”

James Hoare ([email protected]) is managing attorney at the Syracuse, New York office of McGivney, Kluger & Gannon.

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