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Abstract: Historical profiles and sources of PAHs at two typical sediment cores (i.e., the shipping route site and the shoal site) were fully compared to probe the controlling factors, specifically the water currents, for the PAHs deposition processes in the Yangtze River Estuary. Compared with ocean water currents, river runoff affected by the water impoundment of the Three Gorges Dam greatly affected the PAHs levels and percent contribution of PAHs sources in the two cores. River runoff hindered the PAHs deposition in shoal site, while a contrary phenomenon was observed for the shipping route site. Though the PAHs in the estuary were mainly from river catchment, only low ring PAHs in the shipping route site were mainly from the upper reach of the river. Coarse sediments with higher organic carbon content also accounted for the higher deposition levels of PAHs in the shipping route site. [Copyright &y& Elsevier]

Highlights: [•] Chronological records of metal deposition at different estuarine sites were studied. [•] Sedimentary metal speciation reveal responses to upstream hydrological events. [•] The transformation of metal speciation can explain the intercepting role of dams. [•] Sediment particles and organic carbon are the proxies for the metals deposition. [Copyright &y& Elsevier]