Abstract:

The present study developed a method for the determination of 32 pesticide residues (17 organophosphorus, 4 pyrethroids, 8 organochlorines, acetochlor, triadimefon and paclobutrazol) in tea by GC-MS. Pesticide residues were extracted from ground tea with acetonitrile in an ultrasonic filed and purified on a graphitized carbon black column, and then determined by gas chromatography with electron ionization mass spectrometric detection in the selected ion monitoring (SIM) mode. The external standard method was adopted for quantification. The recoveries for the 32 pesticides in tea spiked at three levels ranges from 48.2% to121.9%, with the RSDs of 0.2%－18.3%, and the detection limits for these pesticides by the method were 0.001 －0.02 mg/kg. This method is rapid, sensitive, and accurate, and its various technical indexes meet the detection requirement of pesticide residues in tea samples.

Key words: GC-MS, tea, multi-residue, pesticides