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Research article - Peer-reviewed, 2020

Serum Half-Lives for Short- and Long-Chain Perfluoroalkyl Acids after Ceasing Exposure from Drinking Water Contaminated by Firefighting Foam

Xu, Yiyi; Fletcher, Tony; Pineda, Daniela; Lindh, Christian H.; Nilsson, Carina; Glynn, Anders; Vogs, Carolina; Norström, Karin; Lilja, Karl; Jakobsson, Kristina; Li, Ying


Background: Firefighting foam–contaminated ground water, which contains high levels of perfluoroalkyl substances (PFAS), is frequently found around airports. In 2018 it was detected that employees at a municipal airport in northern Sweden had been exposed to high levels of short-chain PFAS along with legacy PFAS (i.e., PFOA, PFHxS, and PFOS) through drinking water.

Objectives: In this study, we aimed to describe the PFAS profile in drinking water and biological samples (paired serum and urine) and to estimate serum half-lives of the short-chain PFAS together with legacy PFAS.

Methods: Within 2 weeks after provision of clean water, blood sampling was performed in all 26 airport employees. Seventeen of them were then followed up monthly for 5 months. PFHxA, PFHpA, PFBS, PFPeS, and PFHpS together with legacy PFAS in water and biological samples were quantified using LC/MS/MS. Half-lives were estimated by assuming one compartment, first-order elimination kinetics.

Results: The proportions of PFHxA, PFHpA, and PFBS were higher in drinking water than in serum. The opposite was found for PFHxS and PFOS. The legacy PFAS accounted for about 50% of total PFAS in drinking water and 90% in serum. Urinary PFAS levels were very low compared with serum. PFBS showed the shortest half-life {average 44 d [95% confidence interval (CI): 37, 55 d]}, followed by PFHpA [62 d (95% CI: 51, 80 d)]. PFPeS and PFHpS showed average half-lives as 0.63 and 1.46 y, respectively. Branched PFOS isomers had average half-lives ranging from 1.05 to 1.26 y for different isomers. PFOA, PFHxS, and linear PFOS isomers showed average half-lives of 1.77, 2.87, and 2.93 y, respectively.

Discussion: A general pattern of increasing half-lives with increasing chain length was observed. Branched PFOS isomers had shorter half-lives than linear PFOS isomers.

Published in

Environmental Health Perspectives
2020, volume: 128, number: 7, article number: 077004

Authors' information

Xu, Yiyi
University of Gothenburg
Fletcher, Tony
London School of Hygiene and Tropical Medicine
Pineda, Daniela
Lund University
Lindh, Christian H.
Lund University
Nilsson, Carina
Lund University
Norström, Karin
Swedish environmental protection agency
Lilja, Karl
Swedish environmental protection agency
Jakobsson, Kristina
Sahlgrenska University Hospital
Li, Ying
London School of Hygiene and Tropical Medicine

Sustainable Development Goals

SDG3 Good health and wellbeing

UKÄ Subject classification

Environmental Health and Occupational Health

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