TITLE:
Assessment of Trace Metal Contamination and Ecological Risks in the Sediments of Lake Kossou and White Bandama River, Angovia Mining Area (Central-West, Côte d’Ivoire)
AUTHORS:
Akissi Marthe Diby Achi, Yéï Marie Solange Oga, Kouassi Ernest Ahoussi, Jean Biemi
KEYWORDS:
Contamination, TME, Sediment, Angovia Mining Zone, Ecological Risk
JOURNAL NAME:
Journal of Environmental Protection,
Vol.17 No.6,
June
12,
2026
ABSTRACT: Artisanal gold mining in Angovia (Côte d’Ivoire) exerts pressures on Lake Kossou and the White Bandama River. Six sediment samples (two riverine and four lacustrine) were analyzed for As, Cd, Cu, Zn, Cr, Ni, Hg, Pb, Fe, and Mn using ICP-AES (Hg by CV AAS). Ecological risks were assessed using geochemical indices (Igeo, DCm), the potential Ecological Risk Index (PERI), sediment quality guidelines (TEC/PEC), and Principal Component Analysis (PCA). Sediments show polymetallic (As, Cd, Cu, Cr, Ni, Hg, Fe, and Mn) enrichment relative to the Upper Continental Crust, while Zn, Pb, and Ni remain at background levels. Chromium is the most abundant metal (mean: 145 mg/kg; max: 284 mg/kg). Acidic pH (mean: 5.76) suggests the Acid Mine Drainage process (AMD). PCA confirms the geogenic component (As, Cu, Zn, Cr, Ni, Pb, Fe, Mn) and the anthropogenic component (Hg). Lead shows mixed sources. Geochemical indices indicate low pollution (L1, FL1) to moderate (L2, L3, L4, FL2). Mercury (Er = 107.14 at L3) has the highest individual toxicity, followed by Cd and As. All concentrations of Cd were below the LOQ (