Polybrominated diphenyl ethers (PBDEs)
What are polybrominated diphenyl ethers (PBDEs)?
Polybrominated diphenyl ethers (PBDEs) are a group of industrial chemicals used as “flame retardant chemicals” and added to products in order to meet flammability standards established in the 1970s. Like a family, the group of PBDEs contains many related chemicals. There were two main commercial mixtures of PBDEs that were added to many household products including upholstered furniture, plastic casings for computers and televisions, carpet padding, baby products (e.g. changing pads and car seats), fabrics, and wire and cable coatings. PBDEs are found in animals and people throughout the world, with some of the highest levels in North America.
Due to health and environmental concerns, a number of U.S. states banned PBDEs and these chemicals stopped being made in the U.S. between 2004 and 2013. Even though PBDEs are no longer made in the U.S., furniture, TVs, and other products that were made with PBDEs remain in our homes, schools, and workplaces. Several countries still manufacture some PBDEs, including China, India, and Japan.
What are the main ways that PBDEs get into people’s bodies, including pregnant women and children?
PBDEs are not chemically bound to the plastics and foam in electronics and furniture, so they come out of these products into the air and dust of the household environment. PBDEs enter people’s bodies in this contaminated dust—you can breathe it in, touch it, and accidentally get dust in your mouth. Young children have much greater contact with PBDE contaminated dust because they crawl, play on the floor and constantly put their hands in their mouths. Therefore, children have higher levels of PBDEs in their bodies than adults.
When a woman is pregnant, PBDEs in her body can move into the developing baby, so babies are exposed to these chemicals before they are born. PBDEs also move from a woman’s body into her breast milk, so when babies breastfeed, these chemicals can enter their bodies. PBDEs get into the outdoor environment too, for example, when PBDE-containing products go to the dump or get recycled. PBDEs persist for a long time in the environment and build up in animals, becoming more concentrated as they move up the food chain. Consequently, PBDEs also enter people’s bodies when they eat foods such as fish and meat that contain PBDEs. Because products that contain PBDEs are recycled into other products like carpet padding, children’s toys, and kitchen utensils, new sources of PBDEs are entering our homes even though these chemicals are no longer made in the U.S.
What are the effects of PBDEs on children’s brain development?
Studies show that some PBDEs are associated with harm to children’s brain capacities that are critical for thinking and success in school. These effects include loss of IQ and problems with verbal comprehension, perceptual reasoning, motor coordination, hyperactivity, impulsivity, and attention. These associations are seen with PBDE exposures before birth (when mom is pregnant) and in young children. These effects may not be a significant problem for any individual child. But when you look at the bigger picture, such effects can pose a substantial burden on the population as a whole because almost everyone has some level of these chemicals in their body. Scientists have found that PBDEs disrupt hormones in the body that are essential for normal brain development; however, PBDEs may affect the developing brain in other ways too. Scientists are also concerned about the toxicity of the flame retardant chemicals used as replacements for PBDEs.