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Your Environment. Your Health.

Prenatal Exposure to Flame Retardants Linked with Lower IQ

Aimin Chen, M.D., Ph.D.; Richard Hornung, Dr.Ph.; Kim Dietrich, Ph.D.; Bruce Lanphear, M.D.
University of Cincinnati College of Medicine, Simon Fraser University
NIEHS Grants P01ES011261, R01ES014575, R01ES020349

NIEHS grantees report that prenatal exposure to polybrominated diphenyl ether (PBDE) flame retardants can lead to lower intelligence quotients (IQs) and greater hyperactivity in five-year-old children. These results add evidence of PBDE’s potential for neurodevelopmental toxicity, and the findings support efforts to reduce PBDE exposures, especially for pregnant women and young children.

PBDEs were widely used as flame retardants in furniture, carpet padding, car seats, and other consumer products until most were removed voluntarily from the market a decade ago. However, nearly all homes and offices still contain some PBDEs. To study the effects of prenatal exposure to PBDEs, the research team measured PBDE levels in 309 women at 16 weeks of pregnancy from 2003 to 2006. Their children were then followed to age 5.

The researchers found that a 10-fold increase in PBDE concentrations during early pregnancy, when the fetal brain is developing, was associated with a 4.5 IQ decrement at age 5. They say that more research is needed to understand the impact of PBDE exposure on the developing brain and note the importance of investigating chemicals and other flame retardants that have replaced PBDEs.

Citation: Chen A, Yolton K, Rauch SA, Webster GM, Hornung R, Sjödin A, Dietrich KN, Lanphear BP. 2014. Prenatal Polybrominated Diphenyl Ether Exposures and Neurodevelopment in U.S. Children through 5 Years of Age: The HOME Study. Environ Health Perspect; doi: 10.1289/ehp.1307562.

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