Determination of organochlorine pesticides residues in tobacco by microwave-assisted extraction

A new method for the determination of 17 organochlorine pesticides(OCPs) in tobacco based on microwave-assisted extraction(MAE) followed by solid-phase extraction(SPE) clean-up is described.Samples were extracted with hexane-ethyl acetate(1∶1),and the extracts were purified by solid-phase extraction using florisil as the adsorbent.Analytes were determined by gas chromatography with electron capture detection(GC-ECD).The recoveries obtained from samples spiked with standards at the concentration levels of 0.01、 0.05 and 0.5 mg/kg were more than 82%,the relative standard deviations(RSD) were in the range of 0.11%～8.2%.The method can be used for simultaneous determination of organochlorine pesticide residues in tobacco.