Diagnostic de la contamination des eaux de la rivière Mulungwishi par les éléments traces métalliques (ETM) : Lubumbashi, Haut-Katanga / RD Congo [ Diagnosis of water contamination of the river Mulungwishi by metal trace elements (ETM) : Lubumbashi, Haut Katanga / RD Congo ]

In the aquatic environment, much of anthropogenic or natural compounds are adsorbed on particulate matter and accumulate in sediment. Sediment can affect the bioavailability of contaminants and therefore toxicity. A transect was established along the river Mulungwishi, 12 stations were selected along this transect and water and sediment samples were collected for laboratory analysis. The results indicate a high concentration of elements in the study (Cu, Co, Pb, Fe, Mn, and Mg), particularly in sediments than in the water. Cu slightly exceeds WHO standards set at 2 mg / L, the station 7. Against the stations 4, 5, 6, 7, and 8 show high concentrations in sediments to Cu, Co. This is explained by the change in physicochemical conditions of rivers. In this case, it is the pH of the water, particularly when acid which facilitates the mobility of certain hazardous components and their transport along the river especially when the speed is great. By cons when the pH of the water is basic, some other elements precipitate and accumulate in sediment, increasing their concentrations, or of the risk of exposure of aquatic fauna, creatures and aquatic plants as well as the man who would exercise any activity on an exposed river has human pressure in all its forms.