Abstract: Abstract:In order to study the effects of various treatment techniques on the removal of PFCs in wastewater and their treatment mechanisms, samples were collected from four wastewater treatment plants (WWTPs) with different treatment techniques, and were analyzed with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) for PFCs. Nine perfluoroalkyl carboxylates (PFCAs, C₄-C₁₂) and two perfluoroalkyl sulfonates (PFSAs, C₄, C₈) were detected with various quantities in both the influents and effluents of WWTPs. PFC pollution levels were significantly negatively correlated with carbon chain length. The total quantities of PFCAs and PFSAs ranged from 81.5-135.9 ng/L and from 3.7-4.6 ng/L in influents, and from 47.4-63.3 ng/L and from 2.8-3.7 ng/L in effluents of different WWTPs, respectively. The removal of PFCs in wastewater showed a similar effect and regularity, which was dependent on the PFC adsorption on the activated sludge, while different microbial treatment techniques in WWTPs exerted little on the PFCs removal.