Assessment of Pesticide Residue Content in Fresh Plant-Based Products Available on the Serbian Market Using the QuEChERS Method Combined with LC-MS/MS and GC-MS/MS

Pesticides play a crucial role in modern agriculture by protecting crops from pests, diseases, and weeds, thereby contributing to increased agricultural productivity and food security. However, their extensive use may lead to the presence of residues in food products, particularly vegetables, which can pose potential risks to human health. Therefore, continuous monitoring of pesticide residues in vegetables is essential to ensure food safety, assess dietary exposure, and protect consumers from possible acute and chronic health effects associated with pesticide intake. In this study, the concentrations of pesticide residues were determined in 1236 samples of 44 vegetable species collected over a four-year period. Vegetables originated from 39 countries, including Serbia (n = 213). Pesticide residues were determined by liquid chromatography–tandem mass spectrometry (LC-MS/MS) and gas chromatography–tandem mass spectrometry (GC-MS/MS) after extraction using a modified QuEChERS protocol. A total of 148 pesticide residues were detected. Of the vegetable samples, 40.13% had pesticide residues at or above 0.01 mg/kg, and 1.78% exceeded the maximum residue limits (MRLs) set by the Serbian regulation. MRL values were most often exceeded in ginger, cucumber, and spinach. The most frequently found pesticide was imidacloprid (detected in 74 samples, 5.99%). Multiple pesticides were detected in 22.01% of the vegetable samples, and one tomato sample contained up to 10 pesticide residues. Based on the available data and further development of a representative dataset, together with appropriate statistical analyses, dietary exposure assessments for pesticides can be conducted.