Per- and Polyfluoroalkyl Substances (PFAS) in Michigan: A Novel High-Throughput Method with Liquid Chromatography...

This study presents a novel method for analyzing per- and polyfluoroalkyl substances (PFAS) in dried blood spots (DBS), employing a hybrid solvent-based and matrix-matched calibration curve, minimal sample volume, and high-throughput preparation. This process produces a concentrated, purified sample, which is analyzed using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). As part of method validation, key performance metrics such as accuracy, precision, sensitivity, carryover, specificity, interferences, and maximum dilution capability were assessed. The method quantifies 39 PFAS compounds across various classes, achieving limits of detection in the low ng L^-1 range, with most analytes having a limit of quantitation below the first calibrator (50 ng L^-1). The total method accuracy exceeded 81%, surpassing the performance goal of ≥70%, while method imprecision was below 28%, outperforming the goal of ≤30%. Specificity, as measured by a normalized percent matrix bias, was below 11%, with limited and minimal matrix effects observed. Interference from bile acids was determined to be insignificant at biologically relevant concentrations. Over the past three years, this method has been successfully utilized in biomonitoring studies of Michigan residents, demonstrating its robustness and efficiency.