WebMD Health News
April 15, 2011 -- Children in California have high levels of flame-retardant chemicals in their bodies, and they appear to be exposed to these chemicals through household dust and food, a new study shows.
The study found that Mexican-American children, whose mothers emigrated from Mexico before they were born, had blood levels of polybrominated diphenyl ethers (PBDEs) that were seven times higher than children of the same age who were born and grew up in Mexico.
“The only levels that we’ve seen in the literature that are higher than the California children blood levels are children living on a hazardous waste site in Nicaragua,” says study researcher Brenda Eskenazi, PhD. Eskenazi is director of the Center for Environmental Research and Children's Health at the University of California, Berkeley.
By comparing children of the same ethnicity who came from roughly the same socioeconomic classes, and whose mothers all came from the same states in Mexico, researchers were able to better pinpoint where the exposure was happening.
And Eskenazi says that because California children’s PBDE levels were higher than those of their mothers, the chemicals don’t appear to be coming from the mothers’ breast milk, as previous studies have shown.
More likely sources of exposure for American children, she thinks, are household dust and food.
Independent experts agree.
“The chemical essentially just evaporates and comes out of your household furniture and your household plastics and so it’s actually dust exposure to children that’s causing these high levels,” says David Andrews, PhD, a chemist and senior scientist with the nonprofit Environmental Working Group in Washington, D.C.
PBDEs are chemicals that are used to keep things from burning.
In the mid-1970s, California created one of the highest standards for furniture flammability in the country. As a result, millions of pounds of flame retardant chemicals have been used in furniture foam, clothing, upholstery, electronics, and in the insulation for electrical wires.
Even though standards in other states aren’t as strict, product manufactures often conform to California’s flammability standards so their products can be sold there.
As a result, studies have shown that Americans have levels of PBDEs in the bodies that are 20 times higher than levels in Europeans. Government health surveys have found that some of the highest blood levels of PBDEs in California residents.
PBDEs have become so pervasive that a 2010 study documented their presence in butter.
Though their health effects are still being investigated, studies in children have linked high blood levels to problems with brain development, learning, attention, and behavior. In adults, high exposures have been associated with difficulty conceiving, menstrual cycle irregularity, low sperm counts, and altered levels of thyroid hormone.
Production of two kinds of PBDEs ceased in the U.S. in 2004. A third kind, deca-BDE, is being phased out, but it isn’t expected to be off the market until 2014.
“Even though the ones that we have the highest concerns about are no longer being produced, they can still break down into these other forms,” says Andrews.
And PBDEs appear to take a long time to break down, which means that they may persist in the environment for years.
WebMD called an industry group for comment, but an answer was not received in time for publication.
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