Researchers investigating the health impacts of prenatal exposure to flame retardants collected blood samples from 309 pregnant women early in their second trimester. Spikes in the levels of one class of flame retardant, polybrominated diphenyl ethers (PBDEs) correlated with behavior and cognition difficulties during early childhood.

Scientists believe that in humans PBDEs can lodge themselves in bodily lipids when contaminated air is inhaled or tainted dust swallowed, although exactly how they may wreak havoc inside the body remains unknown. Tests on animals suggest that the chemicals disrupt the endocrine system. The chemical structure of PBDEs strongly resembles thyroid hormones, and they affect thyroid regulation and decrease the level of thyroid hormones in the blood of animals. These hormones drive growth and development—in particular, brain development. Animal studies have also found that exposure to PBDEs in the womb and via nursing may damage the thyroid system and alter newborns’ brains.

Children are considered to be at particular risk of encountering hazardous dust because they spend so much time close to the floor and often put their hands in their mouths. Moreover, “you are having an impact during critical windows of development, and if you mess up development when brain structures or neuropathways are forming there may not be an ability to repair them later on,” says Linda Birnbaum, director of the National Institute of Environmental Health Sciences. “We don’t have data on whether or not the cognitive or behavioral impacts will reverse. We know from many other exposures to different kinds of environmental compounds that impact behavior or intelligence that [the impact] doesn’t go away.” Chen plans to follow the kids in his study for the next few years to help glean any long-term effects.

Furniture-makers have continued to use flame retardants because of a state law—the California Technical Bulletin 117. It says the furniture sold within state borders must withstand a 12-second exposure to a small flame without igniting. That state regulation has become the de facto law of the land as manufacturers have sought to comply with it so they can sell their wares throughout the U.S. But California is revising its standard so that products will only have to pass a “smolder test” that would prevent fires but would not require flame retardant use in manufacturing. State legislators may finalize the revision later this summer or in the fall.

Products treated with PBDE are not labeled as such, but Chen says parents can take precautions to reduce exposure by having children wash their hands to diminish dust ingestion, and by replacing old furniture and changing old carpet padding.”

Read the full article here – https://www.scientificamerican.com/article/flame-retardants-linked-lower-iq-hyperactivitiy-children/