Food Safety and Environmental Stewardship Program

A fast and easy modified QuEChERS (quick, easy, cheap, rugged and safe) extraction method has been developed and validated for determination of 33 parent and substituted polycyclic aromatic hydrocarbons (PAHs) in high-fat smoked salmon that greatly enhances analyte recovery compared to traditional QuEChERS procedures. Sample processing includes extraction of PAHs into a solution of ethyl acetate, acetone and isooctane followed by cleanup with dispersive SPE and analysis by GC-MS in SIM mode. Method performance was assessed in spike recovery experiments (500 μg/g wet weight) in three commercially available smoked salmon with 3-11% fat. Recoveries of some 2-, 3- and 5-ring PAHs were improved 50-200% over traditional methods, while average recovery across all PAHs was improved 67%. Method precision was good with replicate extractions typically yielding relative standard deviations <10%, and detection limits were in the low ng/g range. With this method, a single analyst could extract and clean up ≥60 samples for PAH analysis in an 8 h work day.