Polychlorinated biphenyls (PCBs) in dated sediment cores from the East China Marginal Seas (Sigma CMSs) and the chronology of the net fluxes to sediments were analyzed. The accumulation of 27 PCBs (Sigma PCBs) in the ECMS sediments is about 5-26 ng cm(-2), with the net depositional fluxes of Sigma PCBs 10 times lower than those observed in the Great Lakes during the 1960s-1970s. Exponential increases in PCB deposition to the ECMS sediments since the 1990s were observed, which closely follows the fast growth of PCB emissions from industrial thermal processes and e-waste related sources in China. Recent PCB fluxes to the study sites in the ECMSs and the Great Lakes are comparable; the former surged forward with a rising tendency, while the latter showed continued decline after the late 1970s. Due to the different PCB application histories and sources between the two regions, the ECMS sediments may remain as a net sink for land-derived PCBs, while sediments in the Great Lake may have been acting as a secondary source releasing PCBs to water. A higher proportion of trichlorobiphenyls in the ECMS sediments than the Great Lakes was indicated, which may imply the net transport of atmospheric PCBs from China. (C) 2019 Elsevier Ltd. All rights reserved. Publication name | ENVIRONMENTAL POLLUTION, 254 10.1016/j.envpol.2019.112972 A NOV 2019 | Author(s) | Wu, Zilan; Lin, Tian; Li, An; Zhou, Shanshan; He, Huan; Guo, Jiehong; Hu, Limin; Li, Yuanyuan; Guo, Zhigang | Corresponding author(s) | LIN Tian lintian@vip.gyig.ac.cn Chinese Acad Sci, Inst Geochem, State Key Lab Environm Geochem, Guiyang 550081, Guizhou, Peoples R China. | View here for the details
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