Monitoring of Pesticide Multi Residues in Selected Cereals Crop Grains in United Arab Emirates

Abstract

Assessing the contamination of cereals and their manufactured products with pesticide residues is a topic of global importance, and monitoring studies are needed to analyze multiple residues at trace levels. Current study was conducted to monitor pesticide residues in various cereals (corn, oats, rice, barley, sorghum and wheat) imported into the UAE as part of official surveillance. A total of 1,440 samples were collected during 2020 and 2021. Modified QuEChERS method for pesticide residue screening based on multi-reaction monitoring (MRM) mode with advanced gas and/or liquid chromatography tandem mass spectrometry were optimized for monitoring 400 pesticides residues in cereals, and the method was validated for oats, rice, barley and corn matrices, following the European Commission guidelines achieving good recovery values in the range 70–120% with relative standard deviation values lower than 20% and providing limits of quantification of the method in the low mg/kg range, in accordance to the maximum residue limits set by European policies and CODEX. Results from monitoring showed that among the Cereals Grains samples, 903 samples (62.7%) were free from detectable residues, while 419 samples (29.09%) contained residues and 121 samples (8.4%) had residues exceeded the MRLs allowed by the EU legislation and/or COEDX. Tricyclazole, Thiamethoxam, Carbendazim and Buprofesin were the most frequently detected exceeded the MRLs in samples.