Concentrations of Potentially Toxic Elements in Groundwater and Surface Water in Ruashi and Annexe Municipalities of Lubumbashi City, Southeastern Democratic Republic of Congo

Groundwater and surface water contamination by PTE (Potentially Toxic Elements) was assessed in Ruashi and Annexe municipalities of Lubumbashi city. Analyses of seventy water samples collected from six drilled wells, eight spade-sunk wells, one river and one spring in both municipalities in 2017 and 2018 were carried out by ICP-SF-MS (Inductively Coupled Plasma-Sector Field Mass Spectrometry). Twenty PTEs including aluminum, arsenic, barium, bismuth, cadmium, cesium, chromium, cobalt, copper, iron, lead, manganese, molybdenum, nickel, strontium, thallium, tungsten, uranium, vanadium and zinc were detected at various concentrations in each one of the samples. Many samples had concentrations and mean concentrations of PTEs, such as aluminum, cadmium, copper, iron, lead, manganese, nickel and zinc, higher than the respective acceptable limits set for drinking water by the EU (European Union), the USEPA (United States Environmental Protection Agency), and the WHO (World Health Organization) standards. Most PTEs being deleterious to human health even at very low concentrations, people who use the groundwater and surface water to meet their water needs in both Ruashi and Annexe municipalities are at risk.