Heavy Metals Analysis in the Vicinity of a Northcentral Nigeria Major Scrap-Iron Smelting Plant

Scrap-iron smelting, a critical industry for metal recycling, is notorious for releasing potentially toxic elements (PTEs) into the environment. This study investigates pollution levels, sources, and health risks of ten PTEs (Fe, As, Cd, Zn, Cu, Mn, Pb, Cr, Co, and Ni) in indoor and outdoor areas surrounding a major scrap-iron recycling plant in northcentral Nigeria. The potential sources of studied PTEs pollution during the rainy and dry seasons were evaluated using Positive Matrix Factorization (PMF) model. Ecological risk assessments of studied PTEs were conducted using different pollution indices such as Enrichment Factor (EF), Geo-accumulation Index (I_geo), Contamination Factor (C_f), Potential Ecological Risks Index (PERI), Nemerov Integrated Pollution Index (NIPI), and Nemerov Integrated Risk Index (NIRI). Out of the 10 PTEs studied, Cd had the highest pollution level and exhibited a high potential to cause cancer in children during the two seasons considered. Sources of PTEs identified for rainy season included recycling process, electronic waste, coal combustion, steel production, and other smelting activities whereas steel production, electronic waste, coal combustion, recycling process, and traffic emission contributed to the PTE levels obtained in the dry season. This study contributes to the understanding of the environmental impact of scrap-iron smelting operations and advocate for the implementation of sustainable practices that protect both human health and the environment.

Graphical Abstract