Ecological and risk assessment of potentially toxic metals in soil near a ceramics company, Ohunene, Kogi State, Nigeria

Abstract

Toxic metal contamination of soils from industries is of concern due to its harmful effects on humans. Atomic absorption spectrophotometry was employed to evaluate the concentrations of seven different metals. Additionally, some of the soil's physicochemical characteristics were determined. The result showed that the mean concentrations of the metals were below background values and the threshold limits of metals in agricultural soil, according to CCME. The metal pollution level showed low contamination (CF < 1) for Co and Zn, while others ranged from moderate contamination (1 ≤ CF < 3) to very high contamination (CF > 6). The Igeo indicates unpolluted to moderately polluted soil. The Igeo result showed that the soil near the ceramics plant was contaminated with Pb, while samples further away from the company showed zero Igeo. For all metals, the HQ values for adults and children are <1. Similarly, HI values were within safe bounds (HI <1). The CRdermal for Ni (7.06E-01) and the CRoral for Ni and Pb for children exceeded the CR threshold limits of 1.0E−04, indicating a lifetime CR for children. Ni and Pb pose carcinogenic risks to children currently, and this may increase in the distant future, thereby affecting adults if left unchecked.