Determination of Pesticide Residues in Tea by Accelerated Solvent Extraction-Gas Chromatography

Objective To determine multi-residues of organochlorines pesticides (OCPs) and pyrethroid pesticides in tea by accelerated solvent extraction-gas chromatography ( ASE-GC ) method. Method Samples were extracted with thiacyclohexane-ethyl acetate (1 ∶ 1,V /V). The extracts were purified by solid-phase extraction by using florisil as a adsorbent and were detected by gas chromatography-electron capture detection ( GC-ECD). Results The recoveries of standard addition at the levels of 0. 01,0. 05 and 0. 25 mg /kg were more than 90% ,the relative standard deviations (RSD) were in the range of 0. 3% -3. 8% . Conclusion The method of ASE-GC is fast,low cost and in good reproducibility,which can be used for the determination of multi-residues of organochlorine and pyrethroid pesticides in tea.