Assessment of Copper and Cobalt Contamination and Ecological Risk in Sediments of the Musonoïe River Watershed (Kolwezi, DR Congo)
DOI:
https://doi.org/10.59228/rcst.026.v5.i2.298Keywords:
Ecological risk, Enrichment factor, Geoaccumulation index, Musonoïe River, DR CongoAbstract
This study assessed the levels of copper and cobalt contamination, as well as the associated ecological risks, in the sediments of the Musonoïe River watershed in Kolwezi, Lualaba Province, in the Democratic Republic of the Congo. Water, soil, and sediment samples were collected and analyzed by ICP-OES to determine the concentrations of copper and cobalt. The spatial distribution of the metals was studied using the inverse distance weighting (IDW) interpolation method. The level of contamination was assessed using the enrichment factor (EF) and the geoaccumulation index (Geo), while ecological risks were estimated using the ecological risk index (Eri). The results revealed high concentrations of Cu and Co in the sediments, with areas of preferential accumulation located primarily near mine tailings and downstream confluence zones. Enrichment factor values range from 17 to 274 for copper and from 54 to 1,225 for cobalt, indicating severe enrichment and highlighting a significant anthropogenic contribution. The geoaccumulation index values ranged from 3 to 7.5 for copper and from 5.2 to 9.7 for cobalt, classifying the majority of sites as heavily to extremely contaminated. The ecological risk assessment revealed very high-risk levels for both metals, with Eri values ranging from 149 to 1,368 for copper and from 271 to 6,126 for cobalt. These results demonstrate a significant accumulation of metals in the sediments of the Musonoïe River watershed and highlight the significant ecological threat posed by mining activities.
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Atibu, E. & Devarajan, N. & Mwanamoki, P. & Tshibanda, J.& Mpiana, PT. & Prabakar, K. & Wildi, W. & Poté, J. (2013). Concentration of metals in surface water and sediment of Luilu and Musonoie Rivers, Kolwezi-Katanga, Democratic Republic of Congo. Applied Geochemistry. 39. 26-32. 10.1016/j.apgeochem.2013.09.021.
Banza, C. & Nawrot, T. & Haufroid, V. & Decrée, S. & Putter, T. & Smolders, E. & Kabyla, B. & Luboya, N. & Ilunga, A. & Mutombo, A. & Nemery, B. (2009). High human exposure to cobalt and other metals in Katanga, a mining area of the Democratic Republic of Congo. Environmental research. 109. 745-52. 10.1016/j.envres.2009.04.012.
Bird, G. (2016). The influence of the scale of mining activity and mine site remediation on the contamination legacy of historical metal mining activity. Environmental science and pollution research international. 23. 10.1007/s11356-016-7400-z.
Ekoa B. et al. (2024). Spatial variation, ecologcal risk, and point sources of environmental trace metals in Lacustrine ecosystems. Soil anss sediment contamination, 33 (1062-1086).
Helali, MA. & Added, A. & Zaaboub, N. & Oueslati, W. (2009). Géochimie des métaux lourds dans les sédiments marins de surface du delta de l'Oued Mejerda. Revue Méditerranéenne de l'Environnement. 484-495.
Jugie, Y. (2021). Les enjeux sécuritaires et environnementaux de l'exploitation minière en République Démocratique du Congo. Mémoire de Master 2. Faculté de Droit et Science Politique Université de Bordeaux.
Kianza FM., Kembisa NL., Mulonso H., Mpingaja MC., & Pasa MJ. (2026). Évaluation des risques écologiques liés aux éléments potentiellement toxiques (métaux lourds) dans les eaux et les sédiments du fleuve Congo : variations saisonnières et dominance du cadmium. Rev. Cong. Sci. Technol., Vol. 05, No. 02, pp. 834-847.
Koudjo AK., Ouro-Sama, Hodabalo DS., Gnon T., Sadikou A. et al. (2021) Etat de la contamination en éléments traces des sédiments du Lac du barrage hydroélectrique de Nangbéto (Togo). 2021. ⟨hal-03182947v1⟩.
Langunu S., Mwanasomwe JK., Colinet G., Shutcha MN (2024). Are Ecological risk indices for trace metals relevant for characterizing polluted substrates in the Katangese Copperbelt (DR Congo) and for assessment for the performance of remediation trials? Environnments, 11(6),122. https://doi.org/10.3390/environments 11060122.
Mbaya, M. (2026). Étude de la pollution par les éléments traces métalliques des sédiments de la rivière YOLO à Kinshasa en République Démocratique du Congo. Revue Congolaise des Sciences & Technologies. 5. 856-865. 10.59228/rcst. 026.v5. I2.291.
Mpinda T., M. Mujinya, B.B. & Mees, Florias & Kasangij, Patrick & Van Ranst, Eric. (2022). Patterns and forms of copper and cobalt in Macrotermes falciger mounds of the Lubumbashi area, DR Congo. Journal of Geochemical Exploration. 238. 107002. 10.1016/j.gexplo.2022.107002.
Mubemba, M., & Mununga, F. & Kaumbu K., JM & Mwilambwe, K. & Maloba, K. & Banza, I. & Mukunto, K. (2017). Influence des sols contaminés en cuivre sur le développement de deux variétés (locale et améliorée) de légumes dans la région de Lubumbashi (RD. Congo). Journal of Applied Biosciences. 115. 11410. 10.4314/jab. v115i1.1.
Mukendi, RM, & Banza, C., & Mukeng, C., & Ngwe, J., & Kalenga, P. (2018). Exposition de l’homme aux éléments tracés métalliques et altération du sperme : étude menée dans les zones minières du Haut-Katanga en République Démocratique du Congo. Pan African Medical Journal. 30. 10.11604/pamj.2018.30.35.13694.
Ngweme NB., Nieme AB., et al. (2024). Heavy metals content and ecotoxicity of sediments from the Congo River. Aùericain journal of environmental sciences.
Nsiala, Gurvitch O., Crispin K. Mulaji, Fernando P. Carvalho, Emmanuel M. Biey, John Poté and Emmanuel K. Atibu (2026). Trace metals and rare earth elements in sediments along the Muanda River estuary and coastal ocean continuum in an oil exploitation area. Discover Sustainability 7:140 https://doi.org/10.1007/s43621-025-02481-2.
Ouattara, AA & Naminata, S. & N'goran, P. & Yao, Koffi M., & Trokourey, A. & Diaco, T. (2022). Evaluation de la contamination des éléments traces métalliques dans les sédiments de la rivière N’zi, Côte d’Ivoire : Assessment of trace metals contamination in sediments of N’zi River, Côte d’Ivoire. International Journal of Biological and Chemical Sciences. 15. 2199-2208. 10.4314/ijbcs. v15i5.38.
Ouattara, AA & Naminata, S. & N'goran, PA. & Yao, Koffi M. & Trokourey, A. & Diaco, T. (2022). Evaluation de la contamination des éléments traces métalliques dans les sédiments de la rivière N’zi, Côte d’Ivoire : Assessment of trace metals contamination in sediments of N’zi River, Côte d’Ivoire. International Journal of Biological and Chemical Sciences. 15. 2199-2208. 10.4314/ijbcs. v15i5.38.
Stoltnow, M. & Schütte, P. (2024). République démocratique du Congo - Étude de cas d’un pays. WP9 - Task 9.4. Africa Maval.
Tarras-WN. & Flachier, A. & Fredriksson, G. & Lane, Stuart & Lundberg, Bo & Sangfors, O. (2009). Environmental Impact of Small-scale and Artisanal Gold Mining in Southern Ecuador. AMBIO: A Journal of the Human Environment. 29. 484-491. 10.1579/0044-7447-29.8.484.
Thamagaba KH., et al. (2026). Monitoring the impacts of mining activities on land cover using remote sensing technologies and machine leachning in the Musonoie copper-cobalt deposit in the Democratic Republic of Congo. International Journal of Remote Sennsing.
Tshilanda JB., Atibu EK., Mulamba AM., et al. (2024). Persistent organic polluants in sediment of the N’djili river (DR Congo). Discover Applied Sciences.
Useni SY., & Boisson, S. & Kaleba, S., & Khonde, C., & Malaisse, F., & Halleux, JM., & Bogaert, J., & Kankumbi, F. (2019). Dynamique de l’occupation du sol autour des sites miniers le long du gradient urbain-rural de la ville de Lubumbashi, RD Congo. BASE. 14-27. 10.25518/1780-4507.18306.
Wang, L. & DU, Yuhang & ZHAO, Z. & ZHANG, W. & MA, Baozhong & W., Cheng-yan. (2023). Application of geometallurgical modeling in SICOMINES refractory copper–cobalt deposit in Congo (Kinshasa). 工程科学学报. 45. 10.13374/j.issn 2095-9389.2023.01.02.001.
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