Critical Review and Screening of Laboratory Supplies for PFAS Analysis in Water Samples

Polyfluoroalkyl Substances (PFAS) in the Environment
Poster Presentation

Prepared by L. Wiest, S. Liang, M. Chang
Restek, 110 Benner Circle, Bellefonte, PA, 16823, United States


Contact Information: landon.wiest@restek.com; 814-353-1300


ABSTRACT

Per- and polyfluoroalkyl substances (PFAS) and related compounds are being analyzed more than ever before. Their use as non-stick coatings, aqueous film forming foams (AFFFs), and food packaging coatings has resulted in widespread application and convenience, but because they are widely used and are very stable, they have accumulated in the environment. Accordingly, testing of soils, waste water and drinking water, to name a few environmental applications, along with PFAS testing in foods continues to increase. Analysis of these compounds appears straightforward at first, but if you try to develop a method without proper awareness of potential sources of contamination, analysis of PFAS contamination can increase dramatically in difficulty. This is why it is critical to remove and prevent all sources of potential PFAS contamination and accumulation throughout your entire workflow. In this presentation, we discuss specific measures we employed to mitigate PFAS contamination from each stage of our workflow. For sample collection, we used polypropylene containers in favor of typical glassware. Screening of solvents indicated which one to use or avoid depending on the analyte list.. During sample preparation and handling we verified that our, sample transfer methods, SPE cartridges, and manifold didn’t contribute to PFAS contamination and for sample analysis, we replaced typical 2 mL sample vials and caps with polypropylene vials and polyethylene caps. Finally, a PFAS delay column was used to mitigate PFAS contamination in an LC-MS/MS during instrumental analysis. All of these measures we employed made it possible for us to meet the stringent requirements established in methods such as US EPA 537.1; contaminant-free laboratory reagent blanks (LRBs), laboratory fortified blanks (LFBs) with RSDs <20% and accuracy within 30% of the true value. We also show the recovery and accuracy of spiked PFAS analytes extracted from tap water.