Determination of Residues of Fensulfothion and Its Metabolites in Chinese Cabbage, Japanese Radish, and Turnips

Abstract

A method was developed using a selective nitrogen-phosphorus detector to determine the combined total residues, as the oxygen analogs, of fensulfothion (O,O-diethyl O-[p-(methylsulfinyl)-phenyl] phosphorothioate) and its 3 metabolites. The procedure was used to determine harvest residues in Chinese cabbage, Japanese radish, and turnips treated with 2 application rates of fensulfothion. Residues found after application of 2 oz active ingredient (AI)/100 lineal ft of row ranged from 0.026 ppm for Japanese radish to 1.543 ppm for turnip greens. When the application rate was doubled, the amount of residue found was approximately doubled.