How variations in concentrations of metal ions and suspended solids downstream river Rwabakazi in Uganda can be used to study pollution


  • Mukasa-Tebandeke, I. Z. Makerere University
  • Karume, I. Makerere University
  • Ssebuwufu, J. University of Kisubi
  • Wasajja , H. Z. Wesleyan University
  • Nankinga, R Wesleyan University, Connecticut USA.
  • Habimana, M Kabale University



Dissolved oxygen, turbidity, Total suspended solids, Electrical conductivity, Concentration of metal ions, Erosion


Pollution is affecting river Rwabakazi in the Nile basin. Its effects are reflected by high turbidity, pH, total suspended solids, (T.S.S.), electrical conductivity, metal ions concentrations, and low concentration of dissolved oxygen (DO5). In this study, we report the variations in selected physicochemical parameters of waters of the Rwabakazi river.  Turbidity, pH, concentrations of selected metal ions, T.S.S., and DO5 of water sampled from three selected sites on the river in Kabale were very high. Mean DO5 fell from 96 ± 2 mg/L to 86± 1.5 mg/L downstream. The mean pH fell from 7.8 ± 0.03 to 7.6 ± 0.04, showing the removal of basic components. The turbidity dropped from370 ± 3 NTU to 305 ± 2 NTU, showing that the haziness of water decreased. The concentration of iron(II) fell from 320 ± 0.3 mg/L to 291 ± 0.2 mgL-1 indicating the fair extent of heavy metal ions downstream. The T.S.S. decreased from 330 ± 5 mg/L to 300± 5 mg/L, and concentrations of calcium and magnesium ions also decreased, providing evidence for self-purification. The available data suggests that river Rwabakazi is polluted as a result of poor agricultural practices, erosion, and flash flooding.  Further studies on nutrient and pesticide pollution of this river need to be carried out, and trees should be planted on steep open surfaces to minimize erosion. 


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Author Biographies

Mukasa-Tebandeke, I. Z., Makerere University

College of Natural Sciences, School of Physical Sciences, Department of Chemistry, Box 7062, Kampala.

Karume, I., Makerere University

Chemistry Department, School of Physical Sciences, College of Natural Sciences

Wasajja , H. Z., Wesleyan University

Departments of Earth Sciences

Nankinga, R, Wesleyan University, Connecticut USA.

Departments of Earth Sciences

Habimana, M, Kabale University

Department of Chemistry, Faculty of Science 


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How to Cite

Mukasa-Tebandeke, I. Z., Karume, I., Ssebuwufu, J., Wasajja , H. Z., Nankinga, R, & Habimana, M. (2020). How variations in concentrations of metal ions and suspended solids downstream river Rwabakazi in Uganda can be used to study pollution. JOURNAL OF ADVANCES IN CHEMISTRY, 17, 44–63.