Document Type : Research article
Department of Food Science and Technology, Damghan Branch, Islamic Azad University, Damghan, Iran.
Vice-Chancellor for Food and Drugs Affairs, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Department of Pharmacoeconomics and Pharma Management, School of Pharmacy, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Food Safety Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
In the current study, a liquid chromatography coupled mass detector was set up to detect and quantify 108 pesticide residues in rice samples. QuEChERS method was applied for sample preparation and different validation parameters were determined to ensure the suitability of the method. The calibration curves were linear in the concentration 0.01-1.00 mg/kg with a coefficient of determination (R2) of more than 0.990 for all compounds. Based on signal to noise studies, the calculated LODs and LOQs were 0.005-0.060 mg/kg and 0.018-0.199 mg/kg, respectively; and acquired mean recoveries at three spiked levels (0.025, 0.200 and 0.800 mg/kg) were 72% - 117% with RSD < 20%. The developed method was used to investigate the occurrence of the studied pesticides in 65 internal and 65 foreign rice samples. The results showed that 14 internal and 15 imported samples were found to be contaminated 12 pesticides in the amounts between 0.027 mg/kg to 0.078 mg/kg and 0.031 mg/kg to 0.081 mg/kg, respectively. According to the Iranian regulations, with the exception of nine prohibited pesticides for rice production in Iran, bioallethrin, cypermethrin, deltamethrin, flutriafol, foramsulfuron, imazalil, phosphamidon, TCMTB, and triasulfuron, three permitted pesticides, cinosulfuron, triadimenol, and tricyclazole, found in positive rice samples were below MRLs established by Iranian National Standard Organization (INSO).