Determination of some pesticide residues in conventional-grown and IPM-grown tomato by using QuEChERS method.

The present study was conducted to determine pesticide (emamectin-benzoate, penconazole and imidacloprid) residues over tomatoes by using QuEChERS method. The method was validated by spiking tomato matrix at 0.1, 1.0, and 10.0 MRL levels of the pesticides. Tomatoes were harvested from two conventional and two Integrated Pest Management-grown fields. Laboratory samples were taken from the bulk samples. Analyses of spiked and real-field tomatoes were performed with QuEChERS procedure. Experimental samples were subjected to LC-MS/MS analysis. As indicated in "CAC/GL 40-1993," representative sample matrix (apple) calibration was used for quantification. The overall recovery was 107.12% with a relative standard deviation of 17.96% (n = 162). Present values were within the specified recovery ranges (60-140%) and repeatability value of (RSD ≤20%) of SANCO. Analysis of field experiment samples showed that both conventional tomato plots had trace levels (less than MRL) of emamectin-benzoate and imidacloprid, whereas there were not any pesticide residues in both IPM tomato plots.