Ecological and Health Risk Assessment of Heavy Metal Contamination in Soil and Plants Around a Cement Factory in Ibese, Ogun State, Nigeria

The health and environmental risk assessment of metal contamination in soil and plants around a cement factory in Ogun State was the main thrust of this study. Topsoil and cassava leaf samples (18 each) were randomly collected from six communities around the factory and a control site farther away. The level of Cd, Zn, Cu, and Pb and Ni was analyzed using standard procedures, and compared against recommended standards. Higher metal concentration from the samples compared to the control site indicate that it is a main contributor to metal pollution in this study. Except for the soil Cd levels, soil and plant metal concentrations were below permissible limits. Mean (mg/kg) ± S.D concentrations for soil Cd, Zn, Cu, and Pb were 3.8±2.7, 6.0±1.9, 20.82±17.9, 0.75 and 58.65±4.4, 7.62±1.3, 6.7±3.9 for plants Zn, Cu, and Ni respectively. The metal potential ecological risk values indicated low to high risk. Cd was the most polluting metal, and Abule-Maria the most polluted site. The level of Zn and Cu in the plants posed no health hazard risk, unlike Ni which had a potentially high hazard index. These are important baseline data and relevant information for designing an environmental plan to manage cement production activity. Keywords: Cement factory, Heavy metal concentration, Environmental pollution, Health hazard risk, Ecological risk