Occurrence and dietary intake of Perfluoroalkyl substances in foods of the residents in Beijing, China.

The human diet has been considered to be the main source of perfluoroalkyl substances (PFASs) intake, but only a few risk assessments for PFASs alternatives and isomers with persistent and bioaccumulative properties were available. Hence, the concentrations and human exposure of 10 linear PFASs, 8 branched PFASs and 4 alternatives were characterised in animal-origin and vegetable dietary food samples consumed by Beijing residents of China. Linear-PFASs were commonly found in fish, while PFBS was mainly found in vegetables. PFASs alternative 6:2Cl-PFESA was mainly detected in freshwater and marine fish, with a mean level of 223 and 158 pg/g ww, respectively. In addition, br-PFOA and br-PFOS were only detected in pork liver and fish samples. The EDI∑PFOA and EDI∑PFOS values were far below the tolerable weekly intake as recommended by EFSA in 2018. However, the occurrence and exposure of PFAS alternatives suggested that the risk of these contaminants should be further evaluated.