Chemicals once used in everyday products to protect children from fire may actually be hurting children before they're even born.
New research shows that prenatal exposure to the flame retardants --- used in items such as baby strollers, pajamas, carpets and electronics --- is linked to lower intelligence and hyperactivity in early childhood.
The study was presented Monday at the annual meeting of the Pediatric Academic Societies in Washington, D.C.,
Chemicals called polybrominated diphenyl ethers (PBDEs) have been used for decades to reduce the risk of fire, but in animal studies it was revealed "PBDEs can disrupt thyroid hormone and cause hyperactivity and learning problems," said lead study author Aimin Chen, MD, PhD, an assistant professor in the Department of Environmental Health at University of Cincinnati College of Medicine.
"Our study adds to several other human studies to highlight the need to reduce exposure to PBDEs in pregnant women," he added.
Chen and his colleagues based their research on blood samples from 309 pregnant women enrolled in a study at Cincinnati Children's Hospital Medical Center to measure PBDE levels.
The study team also performed intelligence and behavior tests on the women's children annually until the children reach 5 years of age.
"We found maternal exposure to PBDEs, a group of brominated flame retardants mostly withdrawn from the U.S. market in 2004, was associated with deficits in child cognition at age 5 years and hyperactivity at ages 2-5 years," Chen said.
An increase in maternal exposure to PBDEs by about ten times was associated with about a four-point IQ deficit in 5-year-old children.
Even though most PBDEs, except Deca-BDEs, are no longer used as a flame retardant in the United States, they are found on many consumer products produced several years ago. The chemicals do not degrade easily, so they remain long periods of time in human tissues and can be transferred to the developing fetus.
"Because PBDEs exist in the home and office environment as they are contained in old furniture, carpet pads, foams and electronics," Chen said, "the study raises further concern about their toxicity in developing children."
The study suggested replacing old items and more frequent hand-washing more often may reduce the risk of exposure to the retardant chemicals, along with replacing old carpet padding or polyurethane foams that may contain PDBEs.