Human Exposure and Elimination Kinetics of Chlorinated Polyfluoroalkyl Ether Sulfonic Acids (Cl-PFESAs)

Abstract

ABSTRACT:The incomplete mass-balance of organic fluorine in human serum indicates the existence of unknown per-and polyfluoroalkyl substances (PFASs) with persistent and bioaccumulative properties. Here we characterized human exposure and elimination kinetics of chlorinated polyfluoroalkyl ether sulfonic acids (Cl-PFESAs) in metal plating workers (n = 19), high fish consumers (n = 45), and background controls (n = 8). Cl-PFESAs were detected in >98% of the sampled individuals with serum concentrations ranging <0.019−5040 ng/mL. Statistically higher median serum levels were observed in high fish consumers (93.7 ng/mL) and metal plating workers (51.5 ng/mL) compared to the background control group (4.78 ng/mL) (Kruskal−Wallis rank sum test, p < 0.01). Cl-PFESAs could account for 0.269 to 93.3% of ∑PFASs in human serum indicating that this compound class may explain a substantial fraction of previously unidentified organic fluorine in the Chinese population. Estimated half-lives for renal clearance (median 280 years; range 7.1−4230 years) and total elimination (median 15.3 years; range 10.1−56.4 years) for the eight carbon Cl-PFESA suggest that this is the most biopersistent PFAS in humans reported to date. The apparent ubiquitous distribution and slow elimination kinetics in humans underscore the need for more research and regulatory actions on Cl-PFESAs and PFAS alternatives with similar chemical structures.

A rapid and fully automatic method for the accurate determination of a wide carbon-chain range of per- and polyfluoroalkyl substances (C4–C18) in human serum

“…Particularly, the average concentrations of F-53B in ordinary people and occupational workers were 1.8 and 11.9 ng mL −1 , respectively, and the detection frequencies were 80% and 100%, respectively. To our knowledge, there is only one previous report of F-53B in human serum [16]. In this study, the mean concentration of F-53B in workers was lower than in high fish consumers (93.7 ng mL −1 ) and metal plating workers (51.5 ng mL −1 ), however, it was higher than that of the background control group (4.78 ng mL −1 ) [16].…”

“…However, in contrast with the analysis of the standard solutions in acetonitrile or water, the serum samples always showed matrix effects. In present study, 13 isotope-labeled internal standards have been used to correct matrix effects on ionization efficiency as well as to compensate for variation in injection, signal variation due to ion suppression or signal enhancement [4,5,14,16,23,26].…”

“…To our knowledge, there is only one previous report of F-53B in human serum [16]. In this study, the mean concentration of F-53B in workers was lower than in high fish consumers (93.7 ng mL −1 ) and metal plating workers (51.5 ng mL −1 ), however, it was higher than that of the background control group (4.78 ng mL −1 ) [16]. Spearman's rank correlation analysis was used to test the correlation between PFOS and F-53B, and a significant positive correlation between PFOS and F-53B (Spearman's = 0.68; p < 0.01) was found, which showed that they may have similar sources.…”

“…High performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) is the most common method for analyzing these compounds [4,5,16,[23][24][25][26], which has good sensitivity and low detection limits for PFASs. Liquid-liquid extraction (LLE) was performed with an ion-pairing agent, such as tetra-nbutylammonium hydrogen sulfate (TBA), and then extracted using methyl tert-butyl ether (MTBE), followed by solid phase extraction (SPE); the extracted liquid is generally used as a pre-treatment to extract and pre-concentrate PFASs from serum samples [4][5][6]16,23] and was regard as an off-line SPE method for the determination of PFASs in human serum.…”

“…Liquid-liquid extraction (LLE) was performed with an ion-pairing agent, such as tetra-nbutylammonium hydrogen sulfate (TBA), and then extracted using methyl tert-butyl ether (MTBE), followed by solid phase extraction (SPE); the extracted liquid is generally used as a pre-treatment to extract and pre-concentrate PFASs from serum samples [4][5][6]16,23] and was regard as an off-line SPE method for the determination of PFASs in human serum. However, the off-line SPE method was time-consuming and solvent-intensive and may introduce errors during the manual pre-treatment process.…”