Persistence of Fipronil and its Metabolites in Cabbage and Soil

摘要

A method for the extraction and estimation of residues of fipronil and three of its metabolites from cabbage and soil was standardized.Mobile phase composition consisting of methanol:water 70:30 was found optimum for resolution of the parent compound and the metabolites.Recovery of fipronil along with three of its metabolites from cabbage as well as from soil ranged from 80-88%.The limit of quantification of fipronil was 0.06 mu g g~(-1)in both commodities.Desulfinyl and sulfone derivatives of fipronil were the major metabolites,found in the field samples of cabbage as well as in soil,which formed after one day and reached their maximum amount on 3~(rd)day after application.The half-life of fipronil in cabbage varied from 7.5-7.6 days.