Trace Metal Contamination of Water in the Lubumbashi River Basin, Kafubu, Kimilolo and Kinkalabwamba Rivers in Lubumbashi City, Democratic Republic of Congo

Concentrations of fifteen trace metals including Aluminum (Al), Vanadium (V), Chromium (Cr), Manganese (Mn), Iron (Fe), Strontium (Sr), Molybdenum (Mo), Silver (Ag), Cadmium (Cd), Tin (Sn), Caesium (Cs), Barium (Ba), Lead (Pb), Bismuth (Bi) and Uranium (U) were investigated in water samples collected from sixteen sampling locations in the Lubumbashi river basin and five locations in Kafubu, Kimilolo and Kinkalabwamba rivers during February, March and April 2016.Chemical analyses of the samples were carried out using ICP-MS (Inductively Coupled Plasma-Mass Spectrometer).Water pH was determined using a pH-meter and pH values ranged from 4.2 to 7.8.The highest mean trace metal levels of water were 5,515.816µgL -1 , 166.925 µgL -1 , 3.898 µgL -1 and 1.879 µgL -1 for Al, Ba, Cr and U, respectively in Kashobwe river, 2,419.522µgL -1 and 17.994 µgL -1 for Fe and Cd, respectively in Kafubu river at its confluence with Lubumbashi rivers, 1,408.136µgL -1 for Mn in Kafubu river 1.36 kilometer downward its confluence with Naviundu river, 222.406 µgL -1 and 0.092 µgL -1 for Sr and Cs, respectively in Kamalondo river 60 meters from the GCM-Lubumbashi (General of Quarries and Mines-Lubumbashi) smelter, 140.294 µgL -1 , 12.063 µgL -1 and 0.008 µgL -1 for Pb, V and Bi, respectively in Munua river, 3.544 µgL -1 for Ag in Kabulameshi river, 1.49 µgL -1 for Mo in Kafubu river and 0.081 µgL -1 for Sn in Tshondo river.The mean concentrations of Al, Cd, Fe, Mn and Pb in water of many rivers and the channel exceeded the maximum admissible limits of the WHO (World Health Organization), USEPA (United States Environmental Protection Agency) and EU (European Union) drinking-water standards.Trace metal contamination of water of the studied rivers, channel and springs might be partially attributed to natural processes, unplanned urbanization, poor waste management and mostly to abandoned and ongoing mining and ore processing activities in Lubumbashi city.