[Single-laboratory Validation Study of an Improved Multi-residue Method for Pesticide Residues in Green Tea Leaves...

Area of Science:

• Analytical Chemistry
• Food Safety

Background:

• Pesticide residue analysis in food products is crucial for public health.
• Existing methods for green tea may require optimization for accuracy and efficiency.

Purpose of the Study:

• To develop and validate a multi-residue method for pesticide detection in green tea leaves.
• To optimize extraction and purification steps for enhanced matrix effect reduction.

Main Methods:

• Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was employed for pesticide analysis.
• Optimization of acetonitrile extraction, hexane-washed distilled water addition, and solid-phase extraction (SPE) columns (Inert Sep® PLS-3 and Supelclean™ENVI-Carb™II/PSA) was performed.
• Method validation included recovery tests for 92 pesticides at 0.01 and 0.1 mg/kg levels.

Main Results:

• The optimized method successfully reduced the matrix effect from green tea.
• Out of 92 tested pesticides, 84 met the validation criteria.
• The limit of quantification was established at 0.01 mg/kg, aligning with Japanese regulatory standards.

Conclusions:

• The developed LC-MS/MS method is effective and validated for analyzing pesticide residues in green tea.
• This method provides a reliable tool for ensuring the safety of green tea products.
• The findings support regulatory compliance with Japanese Food Sanitation Law limits.