Perfluorinated compounds (PFCs) are a wide class of emerging pollutants. In this study, we applied the US EPA method 533 for the determination of 21 PFCs in river water samples. In particular, this method was used to investigate the presence of the target PFCs in six rivers in central Italy during a 4-month-long monitoring campaign. In 73% of the analyzed samples, at least some of the target PFCs were detected at concentrations higher than the limit of detection (LOD). The sum of the 21 target analytes (∑21PFCs) ranged from 4.3 to 68.5 ng L−1, with the highest concentrations measured in the month of June, probably due to a minor river streamflow occurring in the warmer summer months. Considering the individual congeners, PFBA and PFPeA, followed by PFHxA and PFOA, were the predominantly detected compounds. Short- and medium-chain PFCs (C4–C9) prevail over the long-chain PFCs (C10–C18), likely due to the increased industrial use and the higher solubility of short-chain PFCs compared to long-chain PFCs. The ecological risk assessment, conducted by using the risk quotient method, highlighted that the risk for aquatic environments associated with PFBA, PFPeA, PFBS, PFHxA and PFOA was low or negligible. Only for PFOA, there was a medium level of risk in two rivers in the month of June. With regard to PFOS, 54% of the river water samples were classified as “high risk” for the aquatic environment. The remaining 46% of the samples were classified as “medium risk.”

Perfluorinated compounds (PFCs) are a wide class of emerging pollutants still under study. In this work, we developed and validate a sensitive analytical method based on HPLC-MS/MS for the determination of 21 PFCs. This method was then used to investigate the presence of the target PFCs in six rivers in central Italy during a 4-months long monitoring campaign. 73% of the analytical determinations resulted higher than the limit of detection (LOD). The ∑21PFCs ranged from 4.3 to 68.5 ng L− 1 with the highest concentrations measured in June month, due to a minor river streamflow occurring in the warm periods. Between the individual congeners, PFBA and PFPeA, followed by PFHxA and PFOA were the predominant congeners detected. The evidence that short and medium chain PFCs (C4-C9) prevail over the long chain PFCs (C10-C18) could be attributed to the increased use and higher solubility of short chain PFCs compared to long chain PFCs. The ecological risk assessment, conducted by using risk quotient (RQ) method, highlighted that for PFBA, PFPeA, PFBS, PFHxA and PFOA the risk for aquatic environments was low or negligible. Only for PFOA there was a medium risk in 2 rivers in June month. As regard PFOS, 54% of the river water samples were classified as “high risk” for the aquatic environment. The remaining 46% of the samples were classified as “medium risk”.