PBDEs have been widely used in consumer products for years because they are effective flame retardants, greatly increasing the fire safety of products ranging from carpeting and cushions to televisions, computers and coffee makers. In recent years, however, concerns have grown with evidence that PBDE concentrations are increasing rapidly both in the environment and in human tissues and body fluids. Toxicological data on PBDEs is still limited, but the compounds have been implicated in developmental, reproductive, neurotoxicity and thyroid effects in rats, mice and fish, and may be carcinogenic. Researchers in Europe and the United States found concentrations of PBDEs higher in Americans than in Europeans, although it is not known if these levels affect human health.
Some studies have suggested that people accumulate PBDEs through diet (similar to polychlorinated biphyenyls or PCBs), however, diet alone does not seem to explain the high levels of PBDEs that have been measured in human breast milk and serum. According to the new NIST/EPA study, house dust and the home environment are likely candidates for other sources of exposure.
A survey of 17 homes in the Washington, D.C., and Charleston, S.C., areas found high concentrations of PBDEs in household dust, ranging from 700 to 30,100 nanograms per gram. Researchers analyzed both dust from floors and clothes dryer lint for 22 variants of commercial PBDEs and found PBDEs in every sample. Interestingly, there was little correlation between PBDE levels and the age of the dwelling or the nu
Contact: Michael Baum
National Institute of Standards and Technology (NIST)