Occurrence, spatial and temporal distributions of perfluoroalkyl substances in wastewater, seawater and sediment from Bohai Sea, China.

In this study, surface seawater and sediment samples were collected from Bohai Sea, China, to investigate the temporal and spatial distributions of perfluoroalkyl substances (PFASs) in that area. The total concentrations of PFASs in seawater and sediment samples ranged from below method limit of quantification (<MLQ) to 99.4 ng/L, and from 0.33 to 2.78 ng/g dw, respectively. PFOA was the predominant PFASs in both of surface seawater and sediment samples, with a median concentration of 4.97 ng/L in seawater and 0.24 ng/g dw in sediment sampled in July, respectively. Seasonal variation of the total PFAS concentrations was found in seawater samples, but not in the sediments. The concentrations of the total measured PFASs in water samples from drain outlets ranged from 103 ng/L to 443 ng/L, which was four times higher than that in seawater from the Bohai Sea, suggesting that discharge of wastewater from drain outlets was responsible for the contamination of PFASs in Bohai Sea area.