Multiresidue Pesticide Analysis in Tea Using GC-MS/MS to Determine 12 Pesticide Residues (GB 2763-2021).

ABSTRACT

Pesticides are widely used on tea plants, and pesticide residues are of significant concern to consumers. The National Food Safety Standard Maximum Residue Limits for Pesticides in Food (GB 2763-2021) was recently amended. However, detection methods for pesticides newly added to the list of residues in beverages have not yet been established. For that reason, this study developed a solid-phase extraction (SPE) and gas chromatography-tandem mass spectrometry (GC-MS/MS) method for determining the residues of 12 pesticides, including four newly added, in black and green tea. Sample preparation processes (sample extraction, SPE clean-up, elution solvent, and elution volume) were optimized to monitor these residues reliably. Multiple reaction monitoring (MRM) was used for GC-MS/MS electron impact (EI) mode determination. Finally, satisfactory recoveries (70.7-113.0% for green tea and 72.0-99.1% for black tea) were achieved at three concentrations (10 µg/kg, 20 µg/kg, and 100 µg/kg). The LOQs were 0.04-8.69 µg/kg, and the LODs were 0.01-3.14 µg/kg. This study provides a reliable and sensitive workflow for determining 12 pesticide residues in tea, filling a gap in the newly revised National Standards.