Pre-natal exposure to flame retardant chemicals may harm the development of a child’s brain, resulting in lower IQ’s, shorter attention spans and less coordination, a new study suggests. The research at the University of California, Berkeley adds to a growing body of evidence that chemicals found in common household items are harmful.
Researchers found that exposure to chemicals known as polybrominated diphenyl ethers (PBDEs) led to a higher risk of physical and mental impairment when the children reached school age. PBDEs are flame retardant chemicals widely found in foam furniture, electronics, carpets, upholstery and other consumer products. They easily leach out into the environment, where they can be inhaled or ingested through dust.
Researchers took blood samples from 279 mothers during pregnancy and from their children when they were 7 years old. The children also took a battery of tests at ages 5 and 7 to assess their IQ and cognitive abilities, including verbal comprehension, perceptual reasoning, working memory and processing speed. Mothers and teachers also completed questionnaires to help evaluate the children’s attention skills and behavior.
“This is the largest and most comprehensive study to date to examine neurobehavioral development in relation to body burden measures of PBDE flame retardants,” said study lead author Brenda Eskenazi, director of the Center for Environmental Research and Children’s Health at UC Berkeley.
“We measured PBDEs both in the mothers during pregnancy and in the children themselves. It shows that there is a relationship of in utero and childhood levels to decrements in fine motor function, attention and IQ.”
The new findings are part of a longitudinal study by the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS), which examines environmental exposures and reproductive health.
Study participants were primarily Mexican-Americans living in an agricultural community in Monterey County, California. Earlier studies found that children from the CHAMACOS group had PBDE blood concentrations seven times higher than children living in Mexico.
PBDEs are known endocrine-disrupting compounds that accumulate in human fat cells. PBDEs can be found in the blood of up to 97 percent of Americans, with those in California having levels nearly twice the national average.
The use of PBDEs increased in the 1970 after a California law went into effect requiring that consumer furnishings be able to withstand a small open flame for 12 seconds without igniting. By 2004, because of health concerns, most compounds containing PBDEs were banned in California and other states. They are still found in products made before the ban.
“Within the range of PBDE exposure levels, 5 percent of the U.S. population has very high exposure levels, so the health impact on children in these extremes could be even more significant,” said Heather Stapleton, associate professor of environmental chemistry at Duke University and one of the nation’s leading experts on human exposure to flame retardant chemicals.
“This new study is very important because it confirms earlier published research on the neurodevelopmental effects of PBDE exposure.”
Researchers suspect that children are more at risk of having higher levels of PBDEs in their bodies than adults because they play on the floor, getting PBDE‐contaminated dust on their hands, and then putting their hands in their mouths. And because PBDEs concentrate in breast milk, babies are exposed when nursing.
“Even though PBDEs are not being used anymore, old couches with foam that is disintegrating will still release PBDEs,” said Eskenazi. “These chemicals will be in our homes for many years to come, so it’s important to take steps to reduce exposure.”
To minimize inadvertent exposure to PDBDEs, Eskenazi recommends that you seal any tears in couches and upholstered furniture, damp mop and vacuum frequently, and wash your hands frequently.
The study is being published in Environmental Health Perspective, a peer-reviewed journal. Funding came from the Environmental Protection Agency and the National Institute of Environmental Health Sciences.