Estimation of redox-sensitive metals in Lafarge cement company’s area in Akamkpa Nigeria: Assessment of ecological health risk

Abstract

Toxic compounds such as redox-sensitive metals usually contaminate the soil. They are implicated in the causation of oxidative stress, a precursor of human diseases and ecological extinction. Having uncontaminated soil serves as the link between plant and animal health quality, and a sustainable ecosystem. Geological accumulation and spatial distribution of redox-sensitive metals in agricultural land can significantly hinder soil fertility, ecological health, food safety, and food security. This study used the soil samples from farmlands near the Lafarge industrial area at Mfamosing, Akamkpa local government area of Cross River State, Nigeria, to assess eight redox-sensitive metals (Cadmium, Chromium, Copper, Nickel, Lead, Arsenic, Cobalt, and Zinc), their spatial distribution, and geo-accumulation. The redox-sensitive metals were screened with an atomic absorption spectrophotometer connected with mass spectroscopy. A geographic information system (GIS) and ArcMap version 10:8:2 was used to infer the risk of the industrial area regarding geo-accumulation, and spatial distribution of redox-sensitive metals in the farmlands. The result shows Cd, Cr, Cu, Ni, Pb, As, Co and Zn have different concentrations among the samples. Three samples - MS2, MS3, and MS8, had the highest arsenic concentration, while samples Ms1, Ms2, Ms5, and Ms8, had the second-highest concentrations of Cadmium, Lead, and Chromium, respectively. The polluted area was moderately contaminated and distributed with other metals - Cu, Ni, and Co, respectively. Comparing these results with those of non-industrial areas, one can infer that the Lafarge industrial area is more contaminated with redox-sensitive metal. To advance this investigation, some microorganisms within the area can be used to verify a metal-hazard impact on the ecosystem and monitor the rise in redox-sensitive metals to predict the risk.