High-Throughput GC/MS and HPLC/MS/MS Techniques for the Multiclass, Multiresidue Determination of 653 Pesticides and Chemical Pollutants in Tea

Abstract

An efficient and sensitive method has been established for simultaneous determination of 653 pesticides in teas by GC/MS and HPLC/MS/MS. The method involved extraction with acetonitrile followed by cleanup using Cleanert-TPT SPE and subsequent identification and quantitation of 490 pesticides by GC/MS and 448 pesticides by HPLC/MS/ MS. The LODs for pesticides determined by GC/MS were between 1.0 and 500 microg/kg, and those determined by HPLC/MS/MS were between 0.03 and 4820 microg/kg. At the low fortification levels of 0.01-100 microg/kg, the average recoveries of 94% of the pesticides determined by GC/MS were between 60 and 120%, 77% of which had an RSD below 20%. For 91% of pesticides determined by HPLC/MS/MS, the average recoveries were between 60 and 120%, 76% of which had an RSD below 20%. The paper also reports a novel SPE column, Cleanert TPT, which comprised graphitized carbon black (PestiCarb), polyamine silica, and amide polystyrene for purifying the tea samples. The results indicated good repeatiblity and reproducibility.