Effect of a Component from Foods on the Determination of Benfuracarb and Carbosulfan by Gas Chromatography

A separative determination method of benfuracarb, carbosulfan, carbofuran and 3-hydroxycarbofuran in agricultural products by GC and HPLC was developed. When benfuracarb and carbosulfan in raw extract or slightly cleaned-up extracts of foods were measured by GC, almost all of them was not recovered, though a corresponding amount of carbofuran was detected. On the other hand, when the same GC test solutions were measured by HPLC, benfuracarb and carbosulfan were quantitatively recovered regardless of the degree of cleanup (with or without Sep-pak Silica or Florisil) of the test solution.Accordingly, benfuracarb and carbosulfan in test solution coexisting with food components were decomposed to carbofuran during GC analysis, and the degree of the decomposition depended on the kind of foods. In order to prevent the decomposition, it was necessary to clean-up the test solutions for benfuracarb and carbosulfan sufficiently.