Distribution of polybrominated diphenyl ethers in the surface sediments of the Taihu Lake, China.

Twenty-eight sediment samples were collected from the Taihu Lake and analyzed to acquire information about the levels, distribution, possible sources, time trend and inventory of polybrominated diphenyl ethers (PBDEs) in the Taihu Lake. Our results showed that the most abundant BDE congeners in surface sediments were BDE-47, 99 and 209, with a median value of 0.124, 0.279, and 22.72 ng(gdw)(-1), respectively. The levels of BDE-209 in our samples were much higher relative to those of the other BDE congeners and made up more than 80% of the PBDEs levels in almost all samples. Disregarding BDE-209, among the seven PBDEs (BDE-28, 47, 99, 100, 153, 154, 183) more concerned, the most abundant ones were BDE-47 and 99, which contributed 44.65% (ranged from 29.02% to 73.11%), 24.24% (ranged from 2.27% to 39.66%) to ∑(7)PBDEs, respectively. The correlation between PBDE and TOC was poor, indicating that PBDEs concentrations in sediments of the Taihu Lake were controlled not only by TOC contents, but also by a combined effect of transport, mixing, depositional mechanisms associated with PBDEs, uncontaminated sediments, or fresh input of PBDEs. As expected, the time trend of PBDEs concentration in surface sediment from Taihu Lake were increasing, and the inventory of ∑(25)PBDEs and BDE-209 were estimated to be 3668 kg and 26296 kg.