[Levels and distribution of the dioxin-like polychlorinated biphenyls (PCBs) in the surface sediment of the Yellow River ].

The levels of DL-PCBs in the surface sediments collected in 15 different sampling sites from the Tibetan Plateau to the Yellow River estuary along the Yellow River were measured using the GC-MS. The concentrations of ∑DL-PCBs ranged from 2. 3 to 14.8 pg.g-1 and the TEQs of DL-PCBs were between 0. 001 4 and 0. 023 1 pgg-1 , with an average of 0. 007 3 pg.g-1. Compared with other domestic and foreign rivers, the DL-PCBs and TEQ levels of the Yellow River were at low levels. The main DL-PCBs congeners in the Yellow River sediments were tetra and penta chlorinated biphenyls. The DL-PCBs congener composition of rural and underdeveloped areas was similar, and there was similar congeners composition between the industry developed areas and the populous areas. Petrochemical industries and hydropower facilities may affect the distribution of DL-PCBs congener in the sediments. A significant correlation between concentrations of DL-PCBs and GDP per capita was found. It indicated that the contamination extent of DL-PCBs in the Yellow River was related with the local economic development, DL-PCBs levels in developed areas were higher than those in remote rural areas.