Determination of fenpropathrin residue by QuEChERS method and GC/MS

Chemical pesticides are used worldwide to control pests. This study investigated the residues of the pesticide fenpropathrin in greenhouse tomatoes (Vendor variety). Sample preparation was performed by QuEChERS method, and solid-phase extraction (SPE) cartridges were used for purification. Residual evaluation of this pesticide was carried out using doses (1, 2, and 4 g/lit) in greenhouse tomatoes. Samples were collected at intervals of one, three, five, seven, and ten days after spraying and analyzed by chromatographic gas spectroscopy. The results were compared with the maximum residue level (MRL equals to 0.5 mg/kg) established by Codex Alimentarius. The recovery of fenpropathrin was estimated to be 98.68% at a level of 0.5 ppm. In addition, the preharvest period for fenpropathrin 2 g/lit was determined in greenhouse tomatoes 3 days after spraying. The results also illustrated that increasing the dose of pesticide enhanced the remaining amount.