Polybrominated diphenyl ethers (PBDEs) in water, surface sediment, and suspended particulate matter from the Yellow River, China: Levels, spatial and seasonal distribution, and source contribution.

Fourteen polybrominated diphenyl ether (PBDE) congeners were measured in water, suspended particulate matter (SPM), and sediment samples collected from the entire expanse of the Yellow River in dry and wet seasons. Higher concentrations of PBDEs were found in the middle and lower reaches of the river compared with those in the upper reaches, ascribed to the relatively developed and urbanized cities located in the areas near the middle and lower reaches. The PBDE concentrations in the samples collected during the dry season were lower than those in the samples collected during the wet season because of thaw and rainfall. The dominant congener, with a contribution of 44.6-90.3%, was BDE-209, which originated from the residual of commercial deca-BDE. Three groups of congeners in all the samples showed good correlations with the coefficient ranging from 0.662 to 0.999 (p < 0.01), indicating common sources and similar environmental behaviors. Regression analysis suggested that the local industrial product (IP) and population density (PD) were good indicators of PBDEs in the water and sediment of the Yellow River.