Determination of the Level of Organophosphorus Pesticides in Tomato Using GC-MS/MS and the Concentration of Some Heavy Metals Using FAAS

This study was carried out to develop and apply a quick, yet efficient, analytical method for simultaneous determination of the residues of the 86 pesticides repeatedly detected in food commodity in Al-Rass province of Al-Qassim Region, Saudi Arabia. The suggested method is based on QuEChERS extraction procedures based on acetonitrile followed by a dispersive solid-phase extraction (d-SPE) with primary-secondary amine (PSA) and bulk of carbograph for clean-up, was applied prior to GC-MS/MS analysis, focusing in particular on tomato crops. The second aim of the study was to measure the levels of some heavy metals using FAAS technique, particularly, Cu, Cd, Zn, Fe and Pb. The third aim was to evaluate the effectiveness of some common household-type preparations and handling procedures for tomato on reducing the levels of the detected pesticide residues as well as the heavy metals. The current findings could provide that the proper home preparation of tomato samples, in particular, soaking in 2% sodium chloride solution and soaking in commercial 5% acetic acid has led to effective elimination of the pesticide ethion from those samples. However, results have shown that there was no significant effect on the levels of heavy metals in the investigated tomato samples after applying the common types of household treatments.