Objective To clarify the occurrence characteristics of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in drinking water in Jiangsu province and to assess its health risks to the population.

Methods The source water, treated water, and tap water samples (n = 54) of 10 water plants in A city of southern Jiangsu and B city of northern Jiangsu were collected respectively, and the concentrations of 11 PFASs were determined by ultra-high performance liquid chromatography-tandem mass spectrometry. Monte Carlo simulation was used for probabilistic risk assessment (PRA), and non-carcinogenic health risks were calculated based on different exposure parameters for each age group.

Results PFASs were commonly detected in water samples, and short-chain PFASs accounted for 59.74%. The average concentrations of PFASs followed the trend of perfluorooctanoic acid (PFOA, 63.80 ng/L) > perfluorohexanoic acid (PFHxA, 47.24 ng/L) > perfluorohexane sulfonic acid (PFHxS, 35.83 ng/L) > perfluorobutyric acid (PFBA, 23.60 ng/L). The average concentration of ∑PFASs in A city was higher than that in B city (P < 0.05), and the concentration in wet season was about twice that in dry season. According to the limit (80 ng/L) specified in the national standard, the over-standard rate of PFOA was 27.78%. Compared with the limit (4 ng/L) specified in the US EPA standard, the over-standard rate of PFOA was 100%. PRA results showed that the probability of PFHxS non-carcinogenic risk quotient HQ > 1 in all age groups was 100% (6–9 years old group had the highest risk).

Conclusions PFASs are widely present in water bodies at various stages of the water supply system in Jiangsu province, and there is a certain risk of excessive exposure. Especially, the non-carcinogenic health risk of PFHxS is significant.