Pesticide Residue Measurement in Commonly Used Vegetables Using the QuEChERS Method

Abstract

The aim of current study was to measure the pesticide residues level in vegetables in the Unaizah city, Saudi Arabia. A total of 40 samples including tomato, cucumber, zucchini and red pepper were analysed for various types of pesticides using Quick Easy Cheap Effective Rugged and Safe (QuEChERS) method. The results show that 65% of samples of supermarket and farms contained 14 types of pesticides but pesticides residue level was below the maximum residue levels (MRL) whereas 30% samples were free from pesticides. A total 05% of the vegetables samples were found to exceed the maximum residue levels (MRLs). Moreover, the results indicate that the tomato samples with residue < MRL were 100%. A total of 20% of the zucchini samples were with residue < MRL and 80% of the red pepper samples were with residue < MRL. Cucumber sample from farms showed insecticides were found to exceed the MRL and none of the fungicides detected exceeded the MRL. However, the concentration of acetamiprid was 0.078 mg kg-1 in cucumber was exceeded the maximum residue levels (MRLs) which was 0.03 mg kg-1 and residues of carbofuran that exceeded the MRLs was 0.026 mg kg-1. Acetamiprid was the most commonly detected pesticides and followed by imidacloprid. The results designated that most of the vegetable samples were contaminated with different types of pesticide residues. The high levels of pesticide residues could be a public health problem including pathogenesis because most of the tested vegetables are commonly used as without cooking. Key words: Vegetables, Maximum residues limit, QuEChERS, GC–MS/MS, LC–MS/MS.