title: Polyfluoroalkyl phosphate esters and perfluoroalkyl carboxylic acids in target food samples and packaging--method development and screening.
abstract: Polyfluoroalkyl phosphate mono-, di-, and tri-esters (mono-, di-, and triPAPs) are used to water- and grease-proof food packaging materials, and these chemicals are known precursors to perfluoroalkyl carboxylic acids (PFCAs). Existing analytical methods for PAPs lack sample clean-up steps in the sample preparation. In the present study, a method based on ultra performance liquid chromatography coupled to tandem mass spectrometry (UPLC/MS/MS) was developed and optimized for the analysis of mono-, di-, and triPAPs, including a clean-up step for the raw extracts. The method was applied to food samples and their PAP-containing packaging materials. The optimized UPLC/MS/MS method enabled the separation and identification of a total of 4 monoPAPs, 16 diPAPs, and 7 triPAPs in the technical mixture Zonyl®-RP. For sample clean-up, weak anion exchange solid phase extraction columns were tested. PAPs standard solutions spiked onto the columns were separated into a fraction containing neutral compounds (triPAPs) and a fraction with ionic compounds (mono- and diPAPs) with recoveries between 72-110%. Method limits of quantification for food samples were in the sub to low picogram per gram range. For quantitative analysis of PAPs, compound-specific labeled internal standards showed to be essential as sorption and matrix effects were observed. Mono-, di-, and/or triPAPs were detected in all food packaging materials obtained from the Swedish market. Up to nine diPAPs were detected in the food samples, with the 6:2/6:2 and 6:2/8:2 diPAPs as the dominant compounds. DiPAP concentrations in the food samples ranged from 0.9 to 36 pg/g, which was comparable to individual PFCA concentrations in the same samples. Consumption of food packed in PAP-containing materials could be an indirect source of human exposure to PFCAs.
authors.affiliation: Department of Applied Environmental Science (ITM), Stockholm University, SE-10691, Stockholm, Sweden, wouter.gebbink@itm.su.se.
authors.forename: Wouter A
authors.initials: WA
authors.lastname: Gebbink
authors.forename: Shahid
authors.initials: S
authors.lastname: Ullah
authors.forename: Oskar
authors.initials: O
authors.lastname: Sandblom
authors.forename: Urs
authors.initials: U
authors.lastname: Berger
mesh_terms: D002264:Carboxylic Acids / Q000032:analysis*; D002853:Chromatography, Liquid; D004952:Esters / Q000032:analysis*; D005466:Fluorocarbons / Q000032:analysis*; D005504:Food Analysis / Q000379:methods*; D005506:Food Contamination / Q000032:analysis*; D018857:Food Packaging; D015386:Hazardous Substances / Q000032:analysis*; D006801:Humans; D010710:Phosphates / Q000032:analysis*; D052616:Solid Phase Extraction; D053719:Tandem Mass Spectrometry / Q000379:methods
chemical_list: D002264:Carboxylic Acids; D004952:Esters; D005466:Fluorocarbons; D015386:Hazardous Substances; D010710:Phosphates