Simultaneous Determination of Isoprocarb and Chlorpyrifos in Rice by GC

A new method was developed for residual analysis of isoprocarb and chlorpyrifos in water,soil,brown rice and paddy by gas chromatography(GC).[Methods] The sample of soil was extracted by acetone,the sample of brown rice was extracted by ethyl acetate,and the sample of paddy was extracted by acetone and water(4∶1,by vol),then extracted by methylene chloride,then concentrated and determined by GC.[Results] The average recoveries of the method ranged from 86.67-105.0%,the relative standard deviations were 0.70-5.73%.The lowest detectable concentration of isoprocarb and chlorpyrifos in samples were 0.01,0.005 mg/kg respectively.[Conclusions] The method had high sensitivity,accuracy and precision and was suitable for the detection of large numbers of samples.