QUANTITATIVE DETERMINATION OF SELECTED HEAVY METALS FROM THE SEWAGE OF SAINT GEORGE BEER FACTORY IN ADDIS ABABA

Abstract

This study was conducted to examine the concentrations of selected heavy metals in sewage from St.George Brewery in Addis Ababa, in order to assess the pollution status of the sewage before it joins the nearby water bodies. Effluent samples were collected from different points and the levels of selected metals (Zn, Cu and Pb) were determined. In this regard, 4 mL of effluent sample were digested by using 6 mL of HCl and 3 mL of H2O2 for 30 minutes at room temperature and the levels of the metals in the digests were analyzed by flame atomic absorption spectrometer and the following results were recorded in mg/L for Zn (1.397 ± 0.07–1.636 ± 0.15), Cu (0.88 ± 0.09– 0.943 ± 0.01). Similarly, the toxic metal Pb was detected to be (1.069 ± 0.014–1.282 ± 0.11 ppm) in the effluent samples. The level of Pb was found to be highest next to Zn followed by Cu. The levels of metals were higher in effluent compared to the water used by Brewery. Generally, the effluent of brewery contains heavy metals in large quantity so that it can be considered as a cause of pollution. Thus, periodic determinations are advisable in view of the potential medium and long-term risks associated with heavy metals contamination.