Analysis of insecticide residues in honey by liquid chromatography tandem mass spectrometry using QuEChERS optimized by the Plackett Burman design

A liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analytical method using a modified QuEChERS sample preparation for the analysis of insecticide residues in honey was developed and validated. The use of the Plackett Burman design in the sample preparation step proved to be effective in optimizing recovery and reducing the matrix effect. For quantification purposes, extract-matched analytical curves were constructed showing linearity (R-2 ) higher than 0.99. The precision (RSD%) of the method was lower than 20% and the accuracy was between 74% and 104%. Lower limits of quantification than the maximum residue limits established by the European Commission and the Brazilian legislative framework were obtained. Insecticide residues were found in 37.3% of 51 real honey samples analyzed, with imidacloprid, clothianidin and dimethoate being the most frequently detected insecticides. The co-occurrence of insecticide residues in samples was frequent. Monitoring insecticide residues in honey is needed to avoid consumer exposure at unacceptable levels.

Automated summary

An analytical method using UHPLC-MS/MS and modified QuEChERS sample preparation for detecting insecticide residues in honey was developed and validated. The method showed effective optimization of recovery and reduction in matrix effect using the Plackett Burman design. Insecticide residues were found in 37.3% of the analyzed honey samples, with imidacloprid, clothianidin, and dimethoate being the most frequently detected.