Levels, Sources, Ecological, and Health Risk Assessment of Heavy Metals in River Sediments in Former and Future River Basin Mining Region, Soummam River, Algeria

The Soummam River, a major watercourse in Algeria and a tributary of the Mediterranean Sea, faces multiple anthropogenic pressures. This study is the first to assess the distribution, levels, ecological and health risks of nine heavy metals (Mn, Fe, Zn, Cu, Cr, Cd, Pb, Ni, and As) in its sediments and identify potential sources. Contamination and enrichment were evaluated using the contamination factor (CF), pollution load index (PLI), enrichment factor (EF), and geo-accumulation Index (Igeo), which consistently indicated low to moderate contamination for most metals but very high contamination for Cd. Ecological risk (ER) assessment revealed very high risk at seven stations. Cancer risk was moderate for adults (Ni) and high for children (Ni and Cd), while non-cancer risk was negligible except for children concerning Fe. Likely sources included mining, agriculture, vehicles, and industrial activities.