Factors Influencing Concentrations of PFAS in Drinking Water: Implications for Human Exposure
Abstract
To evaluate possible factors influencing per- and polyfluoroalkyl substances (PFAS) concentrations in drinking water and to estimate human exposure to PFAS via drinking water, concentrations of ten high-concerned PFAS were measured in samples of tap water from the UK (n = 41) and China (n = 14) as well as in bottled water which including 87 brands originating from 15 different countries (n=112). Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) were detected in nearly all samples and were the dominant PFAS detected in bottled water in this study. Detection frequencies for other target PFAS were between 67% and 93%. Concentrations of Ʃ10PFAS in glass bottled water (mean ± SE = 1.4 ± 0.092 ng/L) exceeded those in plastic bottled water (0.93 ± 0.17 ng/L), were higher in still water (1.06 ± 0.24 ng/L) than in sparkling water (0.87 ± 0.18 ng/L), and were significantly greater (p<0.01) in natural mineral water (0.82 ± 0.092 ng/L) than in pure water (0.47 ± 0.040 ng/L). Significantly (p<0.001) higher Ʃ10PFAS concentrations were present in tap water from China (mean ± SE = 9.2 ± 1.2 ng/L, with PFOS and perfluorobutane sulfonate (PFBS) dominant) than in UK tap water (2.7 ± 0.23 ng/L, in which PFBS and PFOA were dominant). Greater proportional contribution of PFOS to ∑10PFAS in tap water from China compared to the UK might be a result of the later implementation of regulatory bans on PFOS in China (2019) compared to the EU (2010). Concentrations of PFOA and PFOS in tap and bottled water analysed in this study were markedly higher than the new USEPA interim health advisory (HA) limit of 0.004 and 0.02 ng/L for PFOA and PFOS respectively, but those of PFBS were well below the HA value of 2000 ng/L. High detection rates of our other target PFAS in both tap water and bottled water highlights the need for monitoring of a wide range of PFAS. Adult daily exposure to Ʃ10PFAS via tap water alone (UK, female (F) = 76 & male (M) = 65 pg/kg bw/day; China, F = 310 & M = 250 pg/kg bw/day) exceeded substantially that ingested via bottled water (UK, F = 28 & M = 24 pg/kg bw/day; China, F = 35 & M = 29 pg/kg bw/day) in both the UK and China. Boiling and filtration can reduce substantially (50% - 90%) exposure to Ʃ10PFAS via drinking tap water.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2023
- Bibcode:
- 2023AGUFMGH41B1107G