Concentration and Ecological Risk Assessments of Potentially Toxic Elements in Soils around Lapite Dump Site, Akinyele Local Government Area, Ibadan, Nigeria

Abstract

The contamination and ecological risk posed by Potentially Toxic Elements (PTEs) on soils around Lapite dumpsite and its environs were assessed using different analytical techniques after complete digestion of the soil using mixed acids. Results showed that the mean concentration of chromium (Cr), cadmium (Cd), and lead (Pb) (153.2mg/kg, 13.83mg/kg, 137.2mg/kg and respectively) have higher concentrations than their crustal abundance (CA). The enrichment factor analysis revealed that most of the soils collected have been enriched with Pb showing the most enrichment at the upper and middle slopes while Cd is the most enriched at the downslope. The contamination factor showed that Cr, Pb and Cd are also the elements showing significant contamination with Cr and Pb moderately contaminating soil (1.54 and 1.62 respectively) and Cd showing very high contamination in the soil (17.3). The ecological risk indices revealed that only Cd has high risk of polluting the soils (519) of the study area while the whole area is considered to be at a high risk of various degrees of pollution (534). Considering the health implications of these concerned elements (Cr, Pb and especially Cd) to the body, the habitants of the study area are advised to move away from these dumpsite and also relocate their farmlands to more environmental friendly sites.

Keywords

• potentially toxic elements; enrichment factor; contamination; ecological risks; pollution