Investigation on Organochlorine Pesticides Residues and Trace Metals in Melon (Colocynthis citrollus L.): A Survey

Several nations of the world are facing crisis level of acute food security and malnutrition which required urgent attention. Melon very rich in protein, oil, minerals, vitamins and good source of energy. As a result, the high contamination of melon with heavy metals and pesticide residues threatens human and ecosystem. Organochlorine Pesticides (OCPs) and trace metals were undertaken in melon obtained from five major towns in Nigeria. Analytical instruments were used to analyze the extracted OCPs from dichloromethane and digested melon samples, respectively. The overall metal content per site of the studied elements in the selected sites was determined and it was in the following decreasing order: Mokwa > Bida > Suleja > Borgu > Saki. The mean metal concentrations were in the following decreasing order: Pb > Zn > Ni > Co > Cd. With exceptions of locations where Ni and Pb were below detection limit, the concentrations of Pb, Cd and Ni in other locations were above WHO/FAO recommended limit. Concentrations of Zn and Co were below WHO/FAO limits. Out of 17 isomers of OCPs analyzed only five isomers were detected. The overall OCPs content per site of the studied elements in the selected sites was determined and it was in the decreasing order: Bida > Borgu > Saki > Suleja. OCP was not detected in melon samples obtained from Mokwa. With exception of endosulfan II, endrin aldehyde, heptachlor, DDE and λ –BHC were above their respective maximum residual limit. Environmental monitoring and education are highly recommended.