Simultaneous multiresidue analysis of 41 pesticide residues in cooked foodstuff using QuEChERS: Comparison with classical method

The principal objective of this study was to develop a simple multiresidue method involving a quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction method for the identification and quantification of 41 pesticide residues in cooked foodstuffs including cooked potatoes, radishes, and rice using GC-mu ECD. The analytes were subsequently confirmed via GC-MS. The results were then compared using the classical method established by the KFDA. The quantitation of individual pesticides was based on matrix-matched calibration curves with a correlation coefficient in excess of 0.993 for the 41 pesticides selected herein. Using QuEChERS, the mean recoveries ranged between 68.6 and 130.0% for the majority of the tested pesticides: however, the classical method exhibited low recoveries for dichlofluanid, tetraconazole, oxadixyl, fenbuconazloe, and paclobutrazol. After QuEChERS, the LODs and LOQs ranged between 0.004 and 0.3 mu g/kg and 0.0125 and 1.0 mu g/kg, respectively. The proposed method was applied successfully to determine the residue levels in cooked foodstuffs, and none of the samples contained detectable amounts of pesticide residues. (C) 2011 Elsevier Ltd. All rights reserved.