Spatial Distribution Of Per-and Polyfluoroalkyl Substances In The Coastal Areas Of Bohai Bay And Their Trophic Transfer Behavior In Bohai Sea

Per-and polyfluoroalkyl substances(PFAS)are a class of emerging persistent organic pollutants(POPs).PFAS could stay in a vaiety of environmental media.PFAS can cause toxic effects on aquatic organisms and will also be enriched to relatively high concentrations with food chains and food webs,posing a potential threat to ecological safety and human health.The Bohai Economic Rim(BER)is one of the most densely populated areas in China,and the Bohai Bay is a semi-closed bay with limited self-purification capacity and sensitivity to environmental changes.In this paper,the solid phase extraction(SPE)pretreatment method and HPLC-MS/MS are used to quantity the concentrations of PFAS.Pollution occurance in marine typical organisms,distribution behavior in environmental media and analysis of their sources based PMF model were also studied.The specific conclusions are as follows:The total concentrations of PFAS(?PFAS)in the water-dissolved phase,surface sediment and SPM were 20.5~684 ng/L,2.69~25.0 ng/g dry weight(dw)and 4.39~527ng/g dw,respectively.PFOA was the predominated compound.HFPO-DA,6:2 Cl-PFESA,8:2 Cl-PFESA and PFECHS were ubiquitous in the coastal areas of Bohai bay.The average partition coefficients(log K_d)of PFAS in the water-SPM system and water-sediment system were 1.56~3.57 and 0.72~2.95,respectively.PFAS with short carbon chains were mainly detected in the water-dissolved phase,but long-chain PFAS mainly occurred in the surface sediment and SPM phases.Source analysis based on the positive matrix factorization(PMF)model found that erosion inhibitor factories,aqueous film-forming foam factories,metal plating plants,fluoropolymer chemical manufacture and food contact materials were the main sources of PFAS in Bohai Bay.The concentrations of?PFAS in marine organisms were in a range of 34.0~177ng/g dw.PFHxA,PFOS and PFOA were the main pollutions with an average concentration of 24.6,22.2 and 19.1 ng/g dw,respectively.The highest PFAS concentration was found in Portunus trituberculatus samples.The concentrations of 6:2Cl-PFESA and 8:2 Cl-PFESA were 0.54~13.8 ng/g dw and 0.03~0.93 ng/g dw,respectively,and the pollution levels have increased.The log BAF values of PFOA and PFOS ranged from 1.51 to 3.77 and 2.44 to 3.91,respectively,and found that long-chain PFAS was more biosynthesis than short-chain PFAS.And the bioaccumulation effect of PFOS is stronger than that of Cl-PFESAs.Only PFOS,6:2 Cl-PFESA and 8:2 Cl-PFESA were found to have a significant positive correlation(P<0.05)with trophic levels,with TMF values of 3.35,4.92 and 2.92,respectively.