Concentrations of some Heavy Metals in Lycopersicon esculentum and Allium cepa Grown in Abarma River Bank, Gusau- Nigeria.

Abstract

 This work evaluated the heavy metals (Cr, Cd, Ni, and Pb) uptake of Lycopersicon esculentum and Allium cepa grown in the river bank of Abarma area, Gusau-Nigeria and assessed the potential risks of such metals. The concentration of metals in this samples follows the; Cd > Cr > Pb > Ni, Tomato is Cr > Cd > Ni > Pb, onion leave as Cr > Cd > Ni > Pb, and onions bulb is Cr > Cd> Ni >Pb. The range concentration of Cd, Cr and Pb in Lycopersicon esculentum Samples Obtained in mg/kg; 10.3±1.7- 6.9±1.8 for Cd, 12.6±3.0-8.0±0.6 for Cr and 4.3±1.0- 2.1±0.6 for Pb, are greater than FAO/WHO guidelines  of 0.2mg/kg, 2.3mg/kg and 0.3mg/kg respectively. But the mean concentrations in mg/kg of Ni 5.5±0.8-2.8±0.8 is below 10mg/kg FAO/WHO guideline. However, the mean concentration in mg/kg of Cd, Cr and Pb and in Allium cepa samples obtained; 24.6±2.5-9.7±0.6(leaves), 10.9±1.2-6.8±2.7(bulbs) for Cd, 11.4±3.5-2.3±1.0(leaves), 15.4±3.6-5.1±1.7(bulbs) for Cr and 4.3±1.2-2.5±0.3(leaves), 3.9±0.3-

2.8±0.3(bulbs) Pb are greater than the guideline for FAO/WHO. And mean concentrations of 8.8±3.25.5±2.1 (leaves), 8.3±2.4-5.1±1.2 (bulbs) for Ni are below 10mg/kg FAO/WHO guideline. The range mean concentration of 6.3±1.6-4.3±0.5mg/kg for Cd in soil samples is greater than the FAO/WHO guideline value of 3mg/kg. And the range mean concentration of Cr, Pb And Ni in the soil samples is below 10mg/kg FAO/WHO guideline values of 400, 100 and 75mg/kg. This confirmed that the soil and vegetables in the area were contaminated with the heavy metals. Thus, the results of this study revealed that the consumption of vegetables grown in the vicinity of sample areas pose a significant health risk to the inhabitants of the area.