Development and Validation of Multiclass Chiral Pesticide Residues Analysis Method in Tea by QuEChERS Combined Liquid Chromatography Quadruple-Linear Ion Trap Mass Spectrometry.

Background: No single pure enantiomeric pesticide residues was investigated and set regulations for tea quality safety and risk assessment. Objective: Due to lack of chiral pesticide analysis method and data, the Maximum residue limits (MRLs) about the chiral pesticides in tea was unknown. Method: An analytical method for the determination of chiral pesticide residues by QuEChERS combined chiral liquid chromatography quadruple/linear ion trap mass spectrometry (LC-MS/MS-Qtrap) was developed and applied to the analysis of various teas. Results: The mean recoveries for pesticides enantiomers ranged from 75.9% to 112.4%. Reproducibility represented by relative standard deviation percentage was 10% or less. Good linearity was achieved for all enantiomers with determination coefficients (r²) greater than 0.99. The detection of limit (CCa) and quantification of limit (CCb) were 0.2 ~1 mg/kg and 0.5~5 mg/kg, respectively. Conclusions: The method was suitable for monitoring the enantiomeric pesticide residues in various teas. Highlights: Enantioselective multiclass pesticide residues were determined in various teas by LC-MS/MS-Qtrap, additional Qtrap scan functions greatly enhance the performance of screening, confirmation, and identification of chiral pesticides. [ABSTRACT FROM AUTHOR]