Kolawole Sunday Adebayo and Odoh Rapheal
Heavy metal concentrations were determined in some of the crops (cassava mash and maize grains) dried along highways “express” in selected states (Benue, Nasarawa and Taraba) in Northern part of the country (Nigeria). The results of chemical analysis indicated that the heavy metal contents of the food crops (cassava mash and maize grains) dried along the highways were higher than the heavy metal contents of food crops (cassava mash and maize grains) from the control areas. The overall ss ranged from 0.210-0.410μg/g, 11.120-18.120 μg/g, 10.200-17.010 μg/g, 0.680-0.920 μg/g 0.350-0.660 μg/g and 9.520-21.330 μg/g for Cd, Cu, Mn, Ni, Pb and Zn in the cassava mash samples, while in the maize grains the heavy metal concentrations ranged from 0.180-0.350 μg/g, 5.780-9.880 μg/g, 7.850-12.250 μg/g, 0.521-0.880 μg/g, 0.310-0.450 μg/g and10.990-16.550 μg/g for Cd, Cu, Mn, Ni, Pb and Zn respectively. Cd concentrations were above WHO/FAO (2007) and Commission regulation (EU 2006) safe limits and Pb above Commission regulation (EU 2006) but below the WHO/FAO (2007) safe limits. Regular monitoring of heavy metals in the food crops dried along the highways is also necessary.
