LC-MS screening of poly- and perfluoroalkyl substances in contaminated soil by Kendrick mass analysis

Abstract

The application of contaminated paper sludge on arable land in southwest Germany caused the occurrence of a broad range of poly-and perfluoroalkyl substances (PFASs) on soil. Recently, the dead-end transformation products (TPs) perfluorooctanoic acid and perfluorooctanesulfonic acid were detected in groundwater and drinking water. The precursors and other transformation products mostly remained unknown. Therefore, HRMS screening by Kendrick mass analysis and assignment of homologous series in combination with suspect screening were applied to identify original PFASs and their TPs in four different soil samples from sites where contaminated paper sludge was applied. In total, twelve compound classes comprising more than 61 PFASs could be fully or tentatively identified. The data reveal that contamination mainly originates from polyfluorinated dialkylated phosphate esters (from 4:2/6:2 to 12:2/14:2), N-ethyl perfluorooctane sulfonamide ethanol-based phosphate diesters (only C 8 / C 8) and transformation products of these precursors. Contamination patterns can be attributed to PFASs used for paper impregnation and can vary slightly from site to site. Keywords Poly-and perfluoroalkyl substances. High-resolution mass spectrometry. Screening. Kendrick mass. Soil. Contamination Abbreviations AIF All-ion fragmentation Da Dalton diPAP Polyfluorinated dialkylated phosphate ester diSAmPAP N-Ethyl perfluorooctane sulfonamide ethanolbased phosphate diester EIC Extracted ion chromatogram ESI Electrospray ionization EtFASA N-Ethyl perfluoroalkanesulfonamide EtFASAA N-Ethylperfluoro-1-alkanesulfonamidoacetic acid EtFOSAA N-Ethylperfluoro-1-octanesulfonamidoacetic acid FASA Perfluoroalkanesulfonamide FOSA Perfluorooctanesulfonamide FTOH Fluorotelomer alcohol FTSA Fluorotelomer sulfonic acid FTUCA Fluorotelomer unsaturated carboxylic acid GenX A m m o n i u m 2 , 3 , 3 , 3-t e t r a f l u o r o-2-(heptafluoropropoxy) propanoate HRMS High-resolution mass spectrometry HS Homologous series KM Kendrick mass KMD Kendrick mass defect LC Liquid chromatography LTZ Landwirtschaftliches Technologiezentrum Augustenberg MeFASA N-Methyl perfluoroalkanesulfonamide MeOH Methanol MFE Molecular feature extraction NH 4 Ac Ammonium acetate Published in the topical collection Persistent and Mobile Organic Compounds-An Environmental Challenge with guest editors Torsten C.

LC-HRMS screening of per- and polyfluorinated alkyl substances (PFAS) in impregnated paper samples and contaminated soils

“…Occurrence of PFAS classes PFAS-impregnated paper samples and PFAS-contaminated soil samples were analyzed by LC-HRMS to compare patterns of homologous series of PFAS. A total of 31 individual compounds out of 8 different compound classes were identified in all samples using a previously described method [24]. The method is briefly described in the "Data evaluation" section.…”

“…According to Schymanski et al (2014) [36], we assigned confidence level 1a for compound identifications that were confirmed with an authentic standard; level 1b for homologues of an identified compound (1a) with systematic retention time shifts; and level 3 if only an accurate mass fit was available. No other levels were assigned (for further information on the systematic retention time shifts, see our previous publication (Bugsel & Zwiener (2020) [24])).…”

“…In a recent case in SW Germany, the "Rastatt case," high PFAS concentrations have been detected in soil, plants, groundwater, and even drinking water [24][25][26][27]. Deposition of compost mixed with waste from the paper industry onto arable land between the years 2000 and 2008 is suspected to be the main cause of contamination [28].…”

In-Vitro and In-Silico Assessment of Per- and Polyfluoroalkyl Substances (PFAS) in Aqueous Film-Forming Foam (AFFF) Binding to Human Serum Albumin

“…Most PFAS identified in this study were also reported by Houtz et al (2013) [ 49 ], Barzen-Hanson et al (2017) [ 2 ], and McDonough et al (2020) [ 29 ] for the same or similar AFFF commercial products. We qualified C 4 and C 6 perfluoroalkyl sulfonamide amino carboxylates and perfluoroalkyl sulfonamido amines that were reported by Houtz et al One pentafluorosulfide-containing eight perfluorocarbon PFAS (8-F5S-PFOS) found in AFFF was also reported by Barzen-Hanson et al We qualified four of six PFOS-substituted compounds (H-PFOS, U-PFOS, Cl-PFOS, and K-PFOS) and one of two PFDS-substituted compounds (H-PFDS) reported by McDonough et al A C 6 containing phosphonic acid and ester functional groups (8:2 monoPAP-diEes) identified in this study was detected in PFAS-contaminated soil (from paper sludge) in Germany [ 50 ]. We identified six novel PFAS that have not been otherwise detected in environmetnal samples to our knowledge: 4-FHp-CycHxA, diTF-IsoBA, Hx-diFB, Uridine-FB, and two C 4 fluoroalkyl esters (N-PFBS-MFPe, N-FBEAc).…”

“Simultaneous targeted and non-targeted analysis of per- and polyfluoroalkyl substances in environmental samples by liquid chromatography-ion mobility-quadrupole time of flight-mass spectrometry and mass defect analysis”

“…This requires rigorous mass and data filtering, which can be streamlined using purpose-built software packages. Mass defect (MD) analysis of F-containing species is another alternative for non-targeted screening in conjunction with HRMS [26][27][28]. Mass defect analysis considers exact isotope masses and is defined as the difference between the exact mass and the nominal mass of a molecular compound.…”