Concentrations Of Selected Metals In Coffee (Coffea Arabica) Beans, Leaves And Supportive Soil Of Gedeo Zone, Ethiopia

The concentration levels of some selected common (Mg, K, Ca), heavy (Cr, Mn, Co, Ni, Cu, Zn) and toxic metals (Cd and Pb) were determined in coffee (Coffea arabica) beans, leaves and supportive soil of Gedeo zone, Ethiopia using Flame Atomic Absorption Spectrometer after microwave digestion of the samples. In coffee beans, among the common metals, concentration of K was determined to be the highest followed by that of Mg and Ca. Out of heavy metals, Cu is present in highest concentration followed by Mn, Zn, Co, Ni and Cr. Similar to coffee beans, in coffee leaves also common metal of highest concentration is K, but followed by Ca and Mg. In soil samples, out of common metals Mg is found to have highest concentration followed by Ca and K. Toxic metals were not detected in all the samples except Cd in soil. This study indicates the presence of all the nutrients under study, with considerable amounts in the coffee beans. In addition, coffee leaves are found to be competitive with the coffee beans in terms of nutrient content. Therefore, this study suggests that coffee leaves may be used for preparing coffee beverage similar to tea. The levels of studied metals in coffee beans and leaves were below the maximum permissible limits set by FAO/WHO and Codex Alimentarius Commission.