Application of QuEChERS Pesticide Multiresidue Method in Traditional Saudi Medicine and Analysis by Gas Chromatography Mass Spectrometry

Abstract

Abstract-The Quick Easy Cheap Effective Rugged and Safe multiresidue method (QuEChERS) has been validated for the extraction of 9 organochlorine pesticides (OCPs) in different matrices of traditional Saudi medicine plants (TSMP). The nine OCPs were hexachlorohexane isomers (HCH, including α-BHC, β-BHC, γ-BHC,), heptachlor, heptachlor-epoxide, and DDT derivatives (o,p-DDE, p,p-DDE, o,p-DDT, p,p-DDT). The method employed a rapid, simple and cost effective procedure. The spiking levels for the recovery experiments were 0.1, 0.5 and 2.0 mg kg-1. Mean recoveries mostly ranged from 82.0% to 104.0% (93.0% on average), while the linearity for 9 OCPs, in the working standard solutions of six concentration levels between 1 and 100 ng/ml, varied from 0.989 to 0.999. Precision, expressed as relative standard deviation (RSD) were generally below 10% (4.72% on average). Based on these results, the methodology was shown to be robust and highly efficient and thus, suitable for monitoring MRL compliance in a wide range of commodity. The contamination status of 9 OCPs on different TSMPs fenugreek, ginger cloves and cinnamon marketed in Riyadh, Saudi Arabia. Among a total of 48 samples which were also tested using a previously validated method, 31.0% (15 samples) contained at least one of the 9 pesticides. We conclude that QuEChERS is a valid method suitable for investigate of OCPs residues in TSMPs.