Study on the Enantioselective Separation, Dissipation, and Residue of Chiral Fenpropathrin in Vegetables by Supercritical Fluid Chromatography-Tandem Mass Spectrometry (SFC-MS/MS)

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 <i>R</i>-fenpropathrin and <i>S</i>-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. <i>R</i>-Fenpropathrin was preferentially dissipated in celery and cucumber, which was opposite in lettuce and pakchoi. The final residues of <i>rac</i>-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 <i>rac</i>-fenpropathrin for all age groups were acceptable. The results would provide a basis for the rational application and risk assessment of fenpropathrin.