Flame retardant chemicals are added to furniture, electronics, and building materials, but they don’t stay inside the products. Instead, these chemicals migrate into house dust, so people are accidentally exposed. Risks are higher for babies and toddlers who spend a lot of time on the floor and ingest contaminants when they put their hand in their mouths. Silent Spring Institute researchers are studying flame retardants as part of the Household Exposure Study, because of evidence that they cause cancer, disrupt thyroid hormones, and affect brain development, including lower IQ and problems with motor skills and attention.
In 2003, Silent Spring Institute researchers were the first to report on PBDE flame retardants in U.S. homes, showing that levels here are ten times higher than in Europe. We also discovered that residues from flame retardants banned from children’s pajamas in the late 1970s still linger in homes, including a chemical identified as a breast carcinogen.
To find out how exposures to PBDE flame retardants in California compare with the rest of the U.S., we tested 40 homes in urban Richmond and 10 in rural Bolinas, CA. We analyzed PBDE levels in blood samples from the U.S. Centers for Disease Control. Californians had double the levels of Penta-BDEs in their blood than other Americans. Penta-BDE levels were 4 to 10 times higher in California homes than elsewhere in the U.S., and many homes had dust levels above the federal health guideline, raising particular concerns for children. High exposures in California are likely due to the state’s unique furniture flammability standard. Fire experts say there are better strategies for fire safety.
PBDEs were phased out across the U.S. because of health concerns, but many other types of flame retardants are in use. To find out about a wide range of flame retardant chemicals and to track exposure changes after the PBDE phase-out, we retested homes in the California Household Exposure Study. This study is the largest investigation of flame retardants in homes. We found 44 chemicals, including carcinogens, hormone disruptors, and chemicals with unknown safety profiles. Most homes had at least one chemical above a federal health guideline. Results show that manufacturers continue to use risky chemicals in products and these chemicals end up in indoor dust at levels of health concern.