1076 / 2019-07-11 14:46:55

Novel and legacy per- and polyfluoroalkyl substances in water, sediment, and air of the Bohai Sea and its surrounding rivers

2、地球化学 > 专题4：河口海岸带生物地球化学

The contamination of per- and polyfluoroalkyl substances (PFASs) in the Bohai Sea and its surrounding rivers have attracted extensive attention in recent years. However, few studies were about the distribution of novel PFASs in multimedia and the coefficient between suspended particle and dissolved phase. In this study, 52 surface water, 30 surface sediment and 6 air samples were collected in the Bohai Sea to investigate the concentration and distribution of 39 target novel and legacy PFASs. Moreover, 35 river water samples from 35 river mouths were collected to estimate the discharge fluxes via suspended particle and dissolved phase. The results showed that, concentrations of total ionic compounds (Σi-PFASs) were ranged from 6.26 to 945 ng/L (mean 77±142 ng/L) in dissolved phase, 0.51 to 325 ng/g dw (mean 48±49 ng/g dw) in suspended particle phase, and 0.70 to 4.13 ng/g dw (1.78±0.76 ng/g) in surface sediment of Bohai Sea and 10 to 13300 ng/L (849±2380 ng/L) in dissolved phase and 0.14 to 1450 ng/g dw (66±199 ng/g dw) in particle phase of river water. In air, the concentrations of ΣPFASs (Σi-PFASs+Σn-PFASs) ranged from 199 to 678 pg/m3 (462±166 pg/m3). Perfluorooctanoic acid (PFOA) was the predominate compound in seawater, sediment and river water, and 8:2 fluorotelomer alcohol (8:2 FTOH) were the predominant compound in air. The highest concentrations of Σi-PFASs were 13300 ng/L in dissolved phase and 1150 ng/g dw in particle phase, found in Xiaoqing River, and the total discharge flux to Bohia Sea was estimated to 12100 kg/y. Short-chained homologues (C<8) have high concentrations in water and sediment, and some alternatives, i.e., 6:2 fluorotelomer .sulfonate (6:2 FTSA), hexafluoropropylene oxide dimer acid (HFPO-DA), and 6:2 chlorinated polyfluorinated ether sulfonic acid (6:2 Cl-PFESA) showed higher or comparable concentrations to legacy PFASs (C8). The distribution coefficient between suspended particles and dissolved phase in seawater were higher than that in river water might because of the salting-out effect. In river and seawater, 26 nontarget suspect PFASs were found by fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS), which could give more concern in Bohai sea and coastal rivers in future study.