Tracking PFAS\nin Drinking Water: A Review of Analytical\nMethods and Worldwide Occurrence Trends in Tap Water and Bottled Water

Per- and polyfluoroalkyl substances (PFAS) used in various\nindustrial\napplications are pollutants of concern for the environment and human\nhealth. Drinking water consumption is one key exposure pathway to\nPFAS, as recently highlighted by multiple studies on their occurrence\nin tap and bottled water worldwide. However, PFAS quantification at\nlow part-per-trillion (ng/L) or part-per-quadrillion (pg/L) concentrations\nremains challenging. PFAS presence in blanks and incomplete method\nrecoveries can lead to false positives or negatives; PFAS concentration\nchanges under different storage durations or conditions can also affect\naccuracy and precision. Here, we review the most recent data related\nto analytical methods that were used in research articles for the\ndetection and quantification of PFAS from drinking water. Commonly\nencountered pitfalls are summarized, and analytical performance is\nappraised including detection limits, recovery, matrix effects, and\nother quality assurance/quality control endpoints. In addition, we\ncollated available guidelines for health advisory levels of PFAS in\ntap water. Finally, we compiled concentration data on legacy and emerging\nPFAS in tap and bottled water.