Simultaneous Analysis and Risk assessment of Quizalofop, Acifluorfen, Bentazone and Its Metabolites residues in Peanut and Straw under field conditions of China

Abstract In this study, we developed and validated a simple and robust method for simultaneous determination of quizalofop-p-ethyl, acifluorfen, bentazone and its two metabolites residues in peanut and straw. All samples were extracted by 0.8% formic acetonitrile (v:v) and pure water. The peanut samples were cleaned up by florisil, while the straw samples were cleansed using florisil and graphitized carbon black (GCB) by adding a desorption procedure at 55°C. The residues were determined by a high performance liquid chromatography electro-spray ionization tandem mass spectrometry (HPLC-MS/MS). The mean recoveries of five analytes in both matrixes ranged from 77% to 110% with relative standard deviations (RSDs) less than 12.6%. The limits of quantification (LOQs) were 0.01 mg/kg in peanut and 0.02 mg/kg in straw. And the limits of detection (LODs) ranged from 0.047 to 0.356 μg/L. The established method was successfully applied to determine the terminal residues of the five analytes in peanut and straw samples from supervised field trials. The results showed that the residues of all analytes were less than LOQs in peanut while that was up to 0.031 mg/kg in straw. Based on residues data in peanut, chronic dietary intake risk of three pesticides was evaluated, and the results showed that the risk of all pesticides were negligible for Chinese residents.