Study on the Enantioselective\nSeparation, Dissipation,\nand Residue of Chiral Fenpropathrin in Vegetables by Supercritical\nFluid Chromatography-Tandem Mass Spectrometry (SFC-MS/MS)

Chiral\nfenpropathrin is a widely used pyrethroid insecticide. A\nfast supercritical fluid chromatography-tandem mass spectrometry (SFC-MS/MS)\nmethod was developed for the enantioselective study of fenpropathrin\nin five kinds of vegetables. The enantioseparation could be completed\nin 2 min, and the recoveries were 75.5–107.7% with RSDs of\n≤15.2%. The dissipation half-lives of <i>R</i>-fenpropathrin\nand <i>S</i>-fenpropathrin were 2.32–3.62 days and\n1.89–3.56 days, respectively. The dissipation of fenpropathrin\nwas the fastest in cucumbers and the slowest in celery cabbage. <i>R</i>-Fenpropathrin was preferentially dissipated in celery\nand cucumber, which was opposite in lettuce and pakchoi. The final\nresidues of <i>rac</i>-fenpropathrin in celery cabbage,\npakchoi, and lettuce were a little above the European Union’s\nmaximum residue limits (MRLs) but less than the China’s MRLs.\nThe acute and chronic dietary intake risks of <i>rac</i>-fenpropathrin for all age groups were acceptable. The results would\nprovide a basis for the rational application and risk assessment of\nfenpropathrin.