Flame retardant chemicals geared toward protecting infants and children may in fact pose behavioral and intelligence problems, according to a new study.

Some flame retardants contain polybrominated diphenyl ethers (PBDEs), which are used to decrease fire risk. The study, which was presented on Monday May 6 at the Pediatric Academic Societies (PAS) annual meeting in Washington, D.C., demonstrated that exposure to the substance among pregnant women correlated with an increased risk of giving birth to an infant with more hyperactivity and lower intelligence in early childhood.

"In animal studies, PBDEs can disrupt thyroid hormone and cause hyperactivity and learning problems," lead author and assistant professor in the Department of Environmental Health at University of Cincinnati College of Medicine Dr. Aimin Chen said in a press release. "Our study adds to several other human studies to highlight the need to reduce exposure to PBDEs in pregnant women."

In conducting the study, researchers took blood samples from 309 pregnant women in order to measure their PBDE levels. In addition, they tracked the women's children during their first five years, throughout which time they were given behavior and intelligence tests. They found that, for each 10-fold increase in the women's exposure to PBDEs, there was a four-point decrease in the IQ scores of infants and children.

One way to help reduce infant exposure to PBDEs is to wash hands frequently and replace older items that may contain the substance. For the most part, the chemicals have not been used in U.S. items since 2004.

"To reduce PBDEs in pregnant women, hand washing to reduce dust ingestion is important," Chen said. "Also reducing PBDEs in the indoor environment may help, such as replacing carpet padding or polyurethane foams that contain PBDEs."