A robust method for the simultaneous quantification of 30 legacy and emerging per- and polyfluoroalkyl substances...

Per- and polyfluoroalkyl substances (PFAS), a class of novel, persistent, bioaccumulative, and globally concerning pollutants, are ubiquitous in marine environments and significantly threaten ecosystem health. The high salinity and complex matrices of marine environments present significant analytical challenges, and existing methods are limited in terms of medium coverage, target diversity, and interference resistance. Therefore, developing a reliable method for simultaneously analyzing trace PFAS across multiple environmental media is critical. To investigate the occurrence, partitioning, and environmental behavior of PFAS in seawater, sediment, and suspended particulate matter (SPM), this study optimized established analytical workflows for different matrices to simultaneously quantify 30 legacy and emerging PFAS. This study optimized solid-phase extraction (SPE) conditions for high-salinity seawater, including sorbent type, pH, and washing and elution procedures, finalizing a protocol comprising a weak anion exchange cartridge at pH 6, washing with 50 mL Milli-Q water, and elution with 0.1% (v/v) ammonia in methanol. Optimal sediment (5 g) processing utilized SPE with 20 mL of methanol-water (1:1, v/v). For SPM, methanol alone was identified as the optimal extraction solvent. The established ultra-performance liquid chromatography-tandem mass spectrometry method demonstrated high sensitivity and excellent selectivity for the 30 compounds. Rigorous quality control ensured reliable data, with most PFAS recoveries at 60%-120% and <20% relative standard deviation. The method was applied to quantify PFAS across marine samples, revealing distinct phase and spatiotemporal distributions (seawater: ∑₃₀PFAS = 1.34-19.9 ng/L; SPM: 3.57-52.3 ng/g dw; sediment: 0.109-1.95 ng/g dw).