PBDEs in indoor dust in South-Central China: characteristics and implications.

Dust samples were collected randomly from 76 houses, 12 offices, 43 outdoor sites, two televisions and two computers in South-Central China. The indoor dust samples were analyzed for the concentrations, congener profiles, and possible sources of polybrominated diphenyl ethers (PBDEs) and compared to similar data obtained for outdoor dusts. The concentrations of Sigma(10)PBDEs (the sum of BDE28, 47, 66, 85, 99, 100, 153, 154, 183, and 209) were 186.6-9654 ng g(-1) (mean=2662 ng g(-1)) and 1737-4408 ng g(-1) (mean=3179 ng g(-1)) for house dust and office dust, respectively. No significant differences were found among the congener profiles of PBDEs in house dust from three different cities. The dominant congener in all dust samples was BDE209, accounting for an average of 96.2%, 99.0% and 97.4% of Sigma(10)PBDEs for house dust, office dust and outdoor dust, respectively. Unlike previous studies, this study found that BDE183 was present in high proportion to Sigma(9)PBDEs (BDE209 excluded) in both indoor and outdoor dusts, in addition to the usually dominant congeners, BDE47 and 99. Sigma(10)PBDEs concentrations in house dust were higher than those in outdoor dust for most comparison samples. Combined with the significantly higher Sigma(10)PBDEs concentrations in television and computer dusts, PBDE-containing products used indoors, including television and computers, were important potential emission sources for PBDEs in indoor dusts. Further studies are required to detail the source of the high levels of BDE183 in Chinese indoor dusts.