Investigation on Pesticide Residue Levels and Heavy Metal Concentrations in Zea-Mays and Oryza Sativa Grains in Biu Area

Abstract

This work reports the result of the investigation of pesticide residues in maize and rice grains grown during the rainy season farming around Biu plateau area. The study aimed at assessing the amount of pesticides residue as well as determine the concentrations of some heavy metals like Cd, Cr, Pb and Mn present in the studied samples. The samples were treated under standard laboratory procedures and were analyzed for pesticide residues using GC-MS technique. The heavy metals presence was investigated using digital colorimeter (DR 3900, HACH). The study showed no presence of pesticide residues in the samples analyzed but revealed the presence of some heavy metals. Those of particular interest include Cd (0.079-0.087 mg/l),Pb (0.65-0,102mg/l) and Mn (0.699-0.770mg/l) as recorded for maize grains. While the results of the metals for rice grains reads as follows. Cd (0.106-0.111mg/l), Pb (0.060-0.065mg/l) and Mn (0.548-0.566mg/l). All the three heavy metals listed were found in maize and rice samples at levels slightly higher than the permissible limits stipulated by W.H.O./F.A.O. The element chromium was not detected among the samples studied.