Liquid- and Gas Chromatography with Tandem Mass Spectrometric Technique to Optimize and Validate the Analysis of Pesticides in Honey: a Large Scope, Multi-Class, Multi-Residue Method.

Background: Honey is a nutrient-rich food item with a complex matrix due to its diverse nutritional components. This complexity poses challenges in the analysis of pesticide residues, affecting accuracy and precision of results. A comprehensive and reliable method is required for the detection and quantification of these contaminants.

Objective: To develop and validate a method for simultaneous analysis of pesticide residues in various honey types using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-tandem mass spectrometry (GC-MS/MS).

Methods: Honey samples (5 g) were extracted using acetonitrile (10 mL) and water (10 mL) for LC-MS/MS analysis, while ethyl acetate (10 mL) was used for GC-MS/MS analysis. The extract was cleaned using primary secondary amine (PSA) before pesticide residue quantification by LC-MS/MS and GC-MS/MS. The method performance was evaluated based on recoveries (70-120%) and repeatability (RSD <20%) at a limit of quantification of 0.01 mg/kg, in accordance with SANTE/11312/2021 guidelines.

Results: The developed method demonstrated compliance with regulatory requirements, ensuring reliable determination of pesticide residues in honey samples. A study on matrix variability from 14 different honey samples revealed that each honey type exhibited a unique matrix effect for the targeted pesticides. To minimize this effect, the use of honey type-specific matrix-matched standards is recommended.

Conclusion: The study successfully developed a simple, robust, and high-throughput analytical method for the quantitative determination of pesticide residues in honey. Given its high selectivity, sensitivity, and rugged performance, the method can be implemented in regulatory testing for the analysis of targeted compounds across a wide range of honey matrices.

Highlights: A method for pesticide residue analysis in honey was developed using LC-MS/MS and GC-MS/MS. The method showed acceptable recoveries (within 70-120%) and repeatability (RSD <20%) at an LOQ of 0.01 mg/kg. Each honey type exhibited a unique matrix effect, emphasizing the need for matrix-matched standards for residue quantifications. The method demonstrated high throughput, selectivity, and sensitivity, making it suitable for regulatory testing.