Estimation of the contamination levels of heavy metals in selected soil samples from Irri, Delta State-Nigeria

Abstract

Soil samples obtained from different locations in Idheze-Irri was analyzed for the presence of heavy metals; lead (Pb), Nickel (Ni), Chromium (Cr), Copper (Cu) and Cadmium (Cd). The estimated mean concentrations of the studied metals were below the global world average respectively while Cd was undetected in the samples. Pollution (contamination) Index (PI) values obtained for Pb, Ni, Cu and Cd are within the category of PI ≤ 1. Enrichment Factor (EF) values indicate that the samples are moderately enriched with Pb and Cu, minimally enriched with Ni and extremely enriched with Cd. Geo-accumulation Index (Igeo) shows that the samples are unpolluted with Pb, Ni, Cu, Cd and Cr. Ecological Risk Index (ERI) values are within the category of ERI ≤ 50 which implies that their quantity in the soil is minimal and hence poses low risk to the environment. All the results and analysis show that the samples are unpolluted with heavy metals (Pb, Ni, Cu, Cd and Cr) and thus the study area is considered safe for habitation and other human activities.

Keywords: Heavy metals, Concentration, Oil spillage, Pollution, Soil samples.