Validation of a Cryo-assisted QuEChERS-GC-MS/MS Method for the Simultaneous Quantification of 16 PAH Residues in Marine Oysters

A modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) protocol incorporating a cryogenic lipid-reduction step was developed and validated for the simultaneous quantification of 16 polycyclic aromatic hydrocarbon (PAH) residues in lipid-rich oyster matrices. The freezing-assisted cleanup was introduced to improve matrix compatibility prior to GC-MS/MS analysis. Method performance was evaluated in terms of linearity, precision, recovery, accuracy, and limit of quantification. Validation was performed at two fortification levels (0.01 and 0.05 ppm). The method showed satisfactory linearity (R2 > 0.995), recoveries within 70–120%, intermediate accuracy below 20%, and a quantification limit of 0.01 ppm for all standards.