Abstract

Syringe filters are used to separate solids from liquids prior to analysis of poly- and perfluoroalkyl substances (PFASs). This is a critical step in sample preparation, as losses of PFASs to the filter material can be significant and lead to underestimation. This study evaluated losses of 21 PFASs in three different matrices (methanol, MilliQ water, and water containing 10 mg L-1 dissolved organic carbon (DOC)) to six different types of syringe filter (0.45 and 0.22 mu m). Regarding sample matrix, the lowest average Sigma(21) PFAS losses were observed in methanol (13%), followed by DOC water (19%) and MilliQ water (26%). Regarding syringe filter material, the lowest average losses of Sigma(21) PFAS in DOC water and MilliQ water were observed for a recycled cellulose filter (average losses 16% and 21%, respectively), while a polypropylene filter had the lowest Sigma(21) PFAS losses in methanol (9%). A smaller polyethersulfone (PES) filter (0.22 mu m, 17 mm empty set) showed significantly (p < 0.05) lower Sigma(21) PFAS losses in DOC water (on average 7.3%) than a larger PES filter (0.45 mu m, 37 mm empty set) (23%). In DOC water, losses to the filter increased by 3.8%, 5.1%, and 8.4% per CF2-moiety for C-3-C-11 perfluoroalkyl carboxylates (PFCAs), perfluoroalkyl sulfonates (PFSAs), and fluorotelomer sulfonic acids (FTSAs), respectively. Comparing different functional groups of PFASs, losses increased as follows: PFCAs < PFSAs < FTSAs < perfluorooctanesulfonamides (FOSAs). Thus, care is needed when including filtration in PFAS analysis, since losses can be significant (up to 100%) depending on the type of syringe filter, target PFAS, and matrix. (C) 2019 Elsevier B.V. All rights reserved.

Keywords

Per- and polyfluoroalkyl substances; Filter; Extraction; Analysis; Method development

Published in

Journal of Chromatography A
2020, Volume: 1609, article number: 460430

SLU Authors

• Sörengård, Mattias

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

• Franke, Vera

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

• Tröger, Rikard

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

• Ahrens, Lutz

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Analytical Chemistry


Publication identifier

DOI: https://doi.org/10.1016/j.chroma.2019.460430

Permanent link to this page (URI)

https://res.slu.se/id/publ/102908