Emerging Methods for the Analysis of Volatile PFAS in Water: HS-SPME-GC/MS

Per- and Polyfluoroalkyl Substances (PFAS) in the Environment
Oral Presentation

Presented by A. Owens
Prepared by A. Sandy, Y. Okamura, E. Wang, R. Marfil-Vega
Shimadzu Scientific Instruments, 7102 Riverwood Drive, Columbia, MD, 21046, United States


Contact Information: [email protected]; 410-910-0884

ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) are pollutants with emerging health and environmental concerns. The legacy and replacement PFAS normally monitored in water samples, such as carboxylates, sulfonates and fluoroalkylether PFAS are analyzed by liquid chromatography- mass spectrometry. However, there are several classes of volatile PFAS used in the manufacturing of these chemicals and fluorotelomer-based polymers that can reach different water bodies through wastewater discharges and air deposition. In this work, a Head-Space Solid Phase Microextraction-Gas Chromatography/Mass Spectrometry (HS-SPME GCMS) analytical method was developed to analyze six classes of volatile PFAS in water using the Shimadzu GCMSQP2020 NX with the AOC-6000 autosampler. Thirteen target compounds were included in the method and quantitation was performed by an internal standard calibration. Laboratory blanks were analyzed during the experiments to ensure the absence of contamination from the laboratory and consumables used. In addition, the evaluation of carryover from the highest calibration standard was conducted by running a blank after this standard. The final method was selective and provided high sensitivity to measure targeted PFAS compounds at trace concentrations. Calibration curve (each with a minimum of seven calibrators) results showed a good linear fit for all compounds with R2 ≥ 0.993 and RF %RSD < 20. Linear range varied for the target compounds.
In this study, none of the target PFAS in the laboratory blank samples showed quantifiable result. The results from the carry over analysis showed < 0.2 % carryover effect. Furthermore, PFAS in the blank were below the quantitation range (2.5 to 25 pg/mL), depending on the target compound) of this method.
This method presents the advantage of simplifying sample extraction and handling for the analysis of volatile PFAS in water, hence, minimizing operational costs, potential errors, and risk of sample-cross contamination. Here we will share the method development experiments and performance results.