Determination Of Selected Heavy Metals In Potato And Soil Samples And Physicochemical Characterization Of Soil In Jibat District Of West Shoa Zone, Oromia, Ethiopia.

Abstract

Potato is well-known species and most important vegetables in household consumption and for commercial purpose. Hence, this was designed to determine some physicochemical properties and concentrations of heavy metals copper (Cu), lead (Pb), iron (Fe), manganese (Mn) cadmium (Cd) and zinc (Zn) in soil samples used for cultivation of potato in West Shoa Zone (Mugno Witete, Maru Gombo , and Maru Konbolcho) in Ethiopia were determined. The results obtained revealed that the mean heavy metal concentrations for Cu, Fe, Zn, Mn,, Cr, Pb, and Cd were 25.79 - 47.89 mg/kg, 298.73 - 831.02 mg/ kg, 19.52 - 441.88 mg/kg, 0.59 -32.15 mg/kg, 6.78 – 37.93 mg/kg, 0.89 - 57.7 mg/kg, and 2.16 - 12.60 mg/kg, respectively. In general, the levels of metals in soil collected from all the sampling sites were found to be decreased in the order of: Fe > Mn > Zn > Cu > Pb > Cd. The limit of detection LOD values for all metals that were analyzed by the AAS and ranges from 0.016 mg/L to 1.340mg/L for potato samples and from 0.0012 mg/L to 0.096 mg/L for soil samples and the limit of quantification (LOQ) values for all metals analyzed in this study ranges from 0.004 to 0.074 mg/Kg. The % RSD values obtained for soil and potato samples were ranged between 0.008 ( in Fe) to 13.56 (in Mn) for all the metals, which were all under the required control limits (≤15%) . These results indicate that the analytical method used was precise and reliable. The results obtained revealed that all the recovery values of soil and potato samples were within the designated acceptance range of 80 % – 120 % for metal analysis. These results reveal that the proposed method was accurate. In generally, from this study it could be concluded that all metals analyzed in both soil and potato samples were below permissible level except Cd and Cr . Therefore, the soils studied were not harmful for cultivation of potato and other agricultural purposes.