Occurrence of per- and polyfluoroalkyl substances in drinking water in China and health risk assessment based on a probabilistic approach

Per- and polyfluoroalkyl substances (PFASs) raise concerns due to their widespread distribution, persistence, and toxicity to humans. Current studies lack the use of exposure parameters for Chinese populations and probabilistic risk assessment (PRA) to assess health risks of PFASs. To provide a scientific basis for the standards of PFASs in drinking water in China, data on concentrations of nine PFASs in 649 drinking water samples were collected from China through literature review. The highest concentration of PFASs was 17.41 ± 20.06 ng/L for perfluorobutyric acid (PFBA). Higher concentrations of PFASs were found in the southeastern coastal and in Sichuan Province. The probability of exceeding the standardized limits for drinking water for PFOA and PFOS was 2.71 % and 0.91 %. PRA and deterministic risk assessment (DRA) were used to assess non-carcinogenic risks in different age groups and provinces. Health risks of PFASs from oral exposure notably exceeded dermal contact. The Hazard Quotient (HQ) for oral exposure to perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) exceeded the acceptable level with a certain probability. The non-carcinogenic risk of exposure to PFASs in drinking water was negligible for the majority of the Chinese population. The study indicates that China should increase research on limits of PFASs in drinking water to reduce the health risks.