Pesticide residues in foods and water in Qatar and their impact on food exposure risk assessment

Purpose The purposes of this study were to analyze fruits, vegetables, water and soil for organochlorine pesticide (OCP) residues and to assess the food exposure of these pesticides in Qatar. Design/methodology/approach Pesticides were quantified in dates, leafy vegetables, fruiting vegetables, water and soil samples using a gas chromatography-electron capture detector and gas chromatography-mass spectrometry. These pesticides were α-benzene hexachloride (BHC), ß-BHC, heptachlor, aldrin, g-chlordane, endosulfan I, α-chlordane, dieldrin, endrin and methoxychlor. Additionally, food exposure risk assessment was performed by estimating daily intakes of OCP. Findings Most analyzed samples contained at least one OCP residue. Endosulfan was the only pesticide that was not detected. The concentrations of OCP in samples were below the maximum residue level (MRL) except endosulfan. Among all the samples analyzed, ˜18% of those exceeded the MRL with respect to the concentrations of methoxychlor and heptachlor. Only intake of methoxychlor (0.018 mg/day) exceeded the MRL (0.01 mg/day). Dates and fruiting vegetables were likely to pose a higher risk than leafy vegetables because they contained heptachlor, endrin and methoxychlor. Leafy vegetables might pose a greater risk than dates and fruiting vegetables because of the presence of β-BHC and dieldrin. Originality/value Eight out of ten OCPs that were measured were found to be below the MRL. These pesticides should be eliminated from the food supply based on the Qatar National Implementation Plan of the Stockholm Convention in 2010. Based on the intake risk assessment, overall, the intake of OCP may not pose a major risk to human health as the concentrations of OCP were below MRL, except methoxychlor. Water and soil are the potential sources of contamination of OCP in foods that were tested in Qatar. To limit the health risks associated with OCPs, there is a need for close monitoring of food and agricultural practices and the types of pesticides imported into Qatar.