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The spatial and temporal distributions of polybrominated diphenyl ethers (PBDEs) were investigated in five sediment cores from the Yangtze River Delta of Yangtze River in China. The surficial concentrations of nine tri- through hepta-BDE congeners (Σ 9 BDEs) and BDE209 were highest at urban sites S3 and S2, followed by rural site S1 and estuary sites S5 and S4, respectively, based on dry sediment weight. Both BDE209 and ∑ 9 BDE concentrations exponentially increased between 1990 and 2008. Commercial deca-BDE, penta-BDE, and octa-BDE products were likely PBDE sources in the study area. The relative abundances of BDE209 were higher in sediment cores from estuary than those from urban and rural locations, ascribing to the atmospheric transport from the adjacent densely populated northern and eastern coastal regions. This conclusion was further confirmed by the higher ratios of BDE47/BDE99 and BDE100/BDE99 in cores from the estuary than those from other locations. Unlabelled Image • Surficial PBDE concentrations largely reflected local urban emissions and inputs. • PBDEs in estuary was influenced by atmospheric deposition and sediment discharge to ocean. • ∑ 9 BDE concentrations increased dramatically in the period of ca. 1990–2008. • The variations of BDE47/BDE99 and BDE100/BDE99 values decreased from bottom to top layers. [ABSTRACT FROM AUTHOR]