[Distribution, Accumulation, and Amplification of Per- and Polyfluoroalkyl Substances in Organisms in Coastal Waters of Bohai Sea].

Per- and polyfluoroalkyl substances （PFAS）, as a class of emerging environmental contaminants, have garnered significant attention because of their widespread presence. With some legacy PFAS phased out, novel PFAS are increasingly produced and utilized. However, research on the pollution characteristics, bioaccumulation, and biomagnification of these emerging ones remains limited. A total of 29 PFAS, including 11 emerging PFAS, in seawater and organism samples （collected from the Bohai Sea） were analyzed using high-performance liquid chromatography-tandem mass spectrometry （HPLC-MS/MS） to study their pollution characteristics, bioaccumulation, and trophic level amplification. The results showed that 12 PFAS were detected in the seawater with ΣPFAS concentrations of 23.06-78.81 ng·L-1. Perfluorooctanoic acid （PFOA） was the main component, closely followed by perfluorobutanoic acid （PFBA）, perfluoropentanoic acid （PFPeA）, and hexafluoropropylene oxide dimer acid （HFPO-DA）. There were 21 PFAS found in marine organisms, with ΣPFAS levels （calculated in dw） ranging from 2.79 to 259.51 ng·g-1. PFOA was the main component, followed by perfluorooctane sulfonic acid （PFOS）, HFPO-DA, and perfluoroundecanoic acid （PFUnDA）. The highest PFAS contamination levels were observed in shellfish. PFOS demonstrated the strongest bioaccumulation, and its average bioaccumulation factor （BAF） had exceeded the benchmark of extraordinary bioaccumulation. For different species, plankton exhibited the strongest bioaccumulation ability. Biomagnification results showed that PFOS had biomagnification ability in this food chain （web）, and its main substitute, 6∶2Cl-PFESA, exhibited biomagnification potential, whereas PFHxS, PFOA, PFNA, and HFPO-DA displayed biomagnification dilution effects.