Simultaneous determination of 8 kinds of acaricides in agricultural products by gas chromatography.

Abstract

Simultaneous determination method of 8 kinds of acaricides (amitraz, benzomate, dicofol (kelthane), chlorfenson (CPCBS), chlorobenzilate, chloropropylate, phenisobromolate and tetradifon) was investigated. Twenty g of minced fruits or vegetables were homogenized with acetone or acetone containing 30% of water. Fifteen g of NaCl was added to each sample, and acaricides were extracted with n-hexane containing 20% ethyl acetate. Three ml of xylene was added to the extract, removed n-hexane-acetone mixture, and this xylene-substituted extract was applied on a florisil column. The column was washed with 50 ml of n-hexane and eluted with 100 ml of n-hexane containing 30% ethyl acetate. Eluate was concentrated to 3.0 ml. Benzomate, kelthane, chlorfenson, chlorobenzilate chloropropylate, phenisobromolate and tetradifon were determined by ECD-GC using capillary column of CBP-1. Amitraz was determined by FTD-GC using OV-17 column. Contents of 8 acaricides in samples including fruits, vegetables, green tea and brown rice were below 0.01 ppm. Recoveries of 8 acaricides added at the concentrations of 0.25-5 ppm in these samples were 60.0-99.9%. Therefore, this method was applicable to the determination of acaricides in agricultural products.