Chiral fenpropathrin is a widely used pyrethroid insecticide. A fast supercritical fluid chromatography-tandem mass spectrometry (SFC-MS/MS) method was developed for the enantioselective study of fenpropathrin in five kinds of vegetables. The enantioseparation could be completed in 2 min, and the recoveries were 75.5-107.7% with RSDs of ≤15.2%. The dissipation half-lives of R-fenpropathrin and S-fenpropathrin were 2.32-3.62 days and 1.89-3.56 days, respectively. The dissipation of fenpropathrin was the fastest in cucumbers and the slowest in celery cabbage. R-Fenpropathrin was preferentially dissipated in celery and cucumber, which was opposite in lettuce and pakchoi. The final residues of rac-fenpropathrin in celery cabbage, pakchoi, and lettuce were a little above the European Union's maximum residue limits (MRLs) but less than the China's MRLs. The acute and chronic dietary intake risks of rac-fenpropathrin for all age groups were acceptable. The results would provide a basis for the rational application and risk assessment of fenpropathrin.
Keywords: SFC-MS/MS; chiral fenpropathrin; enantioselective dissipation; risk assessment; vegetables.