News Headline: Pregnant women get new mercury warning

[lovechild]

Pregnant women get new mercury warning


By Michael Hawthorne Tribune staff reporter

More than 15 percent of children born in the United States could be at risk for brain damage and learning difficulties due to mercury exposure in the womb, according to a new government analysis that identifies certain types of fish as the culprits.


Several recent studies led the Environmental Protection Agency (news - web sites) to conclude that up to 630,000 of the 4 million babies born annually in the U.S. could have mercury blood levels at or above the agency's safety limit, almost double the EPA's previous estimate.


The more-alarming analysis comes amid a flurry of new concern about mercury. New research, released Friday, found that mercury, a highly toxic metal, can irreversibly damage parts of the brain before birth. Also, the federal government is considering new regulations and advisories about mercury.


Most of the mercury in newborns comes from fish eaten by their mothers. The Food and Drug Administration (news - web sites) is crafting new guidelines that advise mothers and women of childbearing age to avoid or limit eating certain types of fish with higher levels of the toxin, including tuna.


The EPA analysis also could influence a Bush administration proposal that would allow the operators of coal-fired power plants, the biggest man-made source of mercury, to buy their way out of limits on the pollutant.


EPA scientists based their new estimate on adult blood samples collected by the Centers for Disease Control and Prevention (news - web sites) and on recent studies that found the average level of mercury in umbilical-cord blood is 1.7 times higher than the level in the mother's blood.


Researchers previously assumed that mercury levels in maternal and umbilical-cord blood were the same.


About 8 percent of women of childbearing age had mercury blood levels exceeding the EPA's safety limit of 5.8 parts per billion. But a newborn could exceed the limit if the level of mercury in the mother's blood was just 3.5 parts per billion, according to a presentation by Kathryn Mahaffey, a top scientist in the EPA's Office of Prevention, Pesticides and Toxic Substances.


In 2000, nearly 16 percent of American women had mercury blood levels of 3.5 parts per billion or higher, according to Mahaffey's Jan. 26 presentation at a scientific forum in San Diego. The EPA posted a summary on its Web site this week.


Fish is big source


Relying on data provided by the CDC, Mahaffey reported that women who had eaten fish at least nine times in a month had seven times as much mercury in their blood as women who had not eaten fish during the previous month.


"This implies we need to do more to reduce the amount of mercury in the environment and do a better job of advising women about the types of fish they should be eating," said Alan Stern, chief of the Bureau for Risk Analysis at the New Jersey Department of Environmental Protection.


Stern recently published a summary of studies of mercury levels in umbilical-cord blood, which Mahaffey used to develop the EPA's new estimate of newborns at risk. Both scientists said the research is still evolving and the estimates could change, but the conclusions are based on a methodology recommended by the National Research Council (news - web sites), an arm of the National Academy of Sciences (news - web sites).


Mercury is a naturally occurring substance that is released into the air by volcanoes, forest fires, incinerators and factories and power plants that burn coal. A small amount falls into lakes, streams and oceans through rain and becomes methylmercury, a potent form of the toxin that becomes more concentrated as it moves up the food chain.


It takes only a teaspoon of mercury to contaminate a 20-acre lake. Infants and children are particularly vulnerable to methylmercury because their nervous systems are still developing.


Irreversible brain damage


If certain types of fish are a large part of a mother's diet, mercury passed to her baby in the womb can irreversibly damage parts of the brain, according to a study published Friday in the Journal of Pediatrics. High mercury exposures in the womb and in a child's early years also can damage the nervous system's control of the heart, the researchers found, reducing the amount of oxygen provided to the rest of the body.





"The current focus on protecting women against this neurotoxin should be expanded to cover children and adolescents as well," the study's chief author, Phillipe Grandjean of the Harvard School of Public Health, said in a statement.

Nutrition experts recommend fish as a key source of protein and heart-healthy omega-3 fatty acids. But 44 states, including Illinois, advise children and women of childbearing age to limit eating of certain types of freshwater fish found to have high levels of mercury. The list in Illinois includes bass, walleye, flathead catfish, sauger, saugeye, muskellunge and northern pike.

In December, the FDA released a draft nationwide advisory for pregnant women, nursing mothers and women of childbearing age to limit their intake of tuna due to mercury contamination. Eating more than 12 ounces of canned albacore tuna a week--an amount equal to two cans of the popular fish--is enough to exceed the EPA's safety limit.

Canned albacore, also known as white tuna, has nearly three times as much mercury as canned light tuna, according to the FDA. The agency had previously warned pregnant women against eating four other types of fish that contain high levels of the toxin: shark, swordfish, king mackerel and tilefish.

Industry figures show women between 18 and 54 make about 85 percent of the tuna purchases at supermarkets.

Mahaffey and others are urging mothers and women of childbearing age to choose fish that have low levels of mercury. Mackerel, sockeye salmon and herring generally have low levels of mercury but high levels of the beneficial omega-3 fatty acids.

Consumers have been bombarded lately with sometimes-conflicting advice about seafood. In addition to the tuna advisory, a recent study showed farm-raised salmon contain significantly higher concentrations of PCBs, dioxins and other cancer-causing pollutants than salmon caught in the wild.

Removing skin and fat can reduce exposure to PCBs in fish. But the technique doesn't work for mercury, which is bound to the meat.

The National Fisheries Institute, an industry group that advises consumers on its Web site to "eat fish to keep your mind sharp," questioned the EPA analysis. "We still believe the health benefits of eating fish outweigh any risks," said Linda Candler, a spokeswoman.

Environmental and public health groups said the research should prompt federal officials to take more aggressive steps to advise women and children which fish are safe to eat.

"We need to deal with this problem now," said Jane Houlihan, vice president of the Environmental Working Group, a non-profit research and advocacy organization. "Women need to know which fish they can eat that will give them essential nutrients without the harmful mercury."

The largest sources of man-made mercury, coal-fired power plants, release about 48 tons of the toxin into the air each year. Illinois ranks seventh in the nation in mercury emissions.

Under a Bush administration proposal, utilities would have until 2018 to reduce mercury emissions by 70 percent. Dirty plants could buy credits from clean ones to avoid or delay installing mercury controls, similar to a system already in place that has reduced emissions of sulfur dioxide, the main ingredient in acid rain.

The EPA had been on track to enforce more-stringent regulations that would have required a faster, deeper cut in mercury emissions. Utilities argued they didn't have technology to meet the agency's target.

Environmental groups have called the administration's proposal an election-year gift to some of Bush's top campaign contributors. Last week, the EPA's advisory committee on children's health said the proposal doesn't go far enough to attack the "significant health threat of mercury to our children, and to healthy child development."

Among other things, the committee said it is concerned that allowing utilities to buy or trade their way out of mercury controls could end up creating "hot spots" of the toxin around the country.

[lovechild]

im so glad that im allergic to fish....

[Mother Mo]

I heard about that on NPR not too long ago. It's disgraceful how our species continues to destroy this planet & it's life.

[Coor]

Well, I was reading i think in Popular Science, about Tuna's mercury levels becoming rediculious. I made my sis in law stop eating it so much. She was eating it like 5 times a week.

[darkvader]

<sigh>

I find it very hard to believe that an appropriately controlled study that could measure the brain damage that is being discussed here is even possible.

Please locate the actual study referred to here and post it. I'd love to see how they did their research.

[Celestial Dung]

Two sites..

http://www.hsph.harvard.edu/press/relea ... 62004.html

shows that the study was done by the Harvard schoo of medical health.

http://www2.us.elsevierhealth.com/scrip ... =jpd041441

and that's the site...I think...the report should come in some time this month.