Fast Determination of Pyrethroid Pesticides in Tobacco by GC-MS-SIM Coupled with Modified QuEChERS Sample Preparation Procedure

An analytical method was developed for the extraction and determination of pyrethroid pesticide residues in tobacco. The modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) method was applied for preparing samples. In this study, methyl cyanide (MeCN)-saturated salt aqueous, was used as the two-phase extraction solvent for the first time, and a vortex shaker was used for the simultaneous shaking and concentration of the analytes. The effects of experimental parameters on extraction and clean-up efficiency were investigated and optimized. The analytes were determined by gas chromatography-mass spectrometry-selected ion monitoring (GC-MS-SIM). The obtained recoveries of the analytes at three different fortification levels were 76.85 - 114.1% and relative standard deviations (RSDs) were lower than 15.7%. The limits of quantification (LOQs) were from 1.28 to 26.6 mu g kg(-1). This method was also applied to the analysis of actual commercial tobacco products and the analytical results were satisfactory.