Investigating Heavy Metal Pollution of a Residential Area in Nsukka, Enugu State of Nigeria and Associated Risks

Abstract

The soils of residential areas close to high traffic roads are susceptible to heavy metal contamination as a result of urban or sub-urban activities. In this study, the heavy metal contamination of a soil area in Nsukka of Enugu state was investigated with a view to ascertaining the geochemical baseline and hitherto contamination. The heavy metals determined were Cu, Pb, Zn, Cr and Cd which were measured by means of Atomic Absorption Spectrometry. The extent of pollution of the soil environment was evaluated using, contamination factor (CF), geochemical accumulation index I_geo, and pollution load index (PLI) whereas the ecological risks was evaluated using potential ecological risk index (PERI). Obtained results show that the mean concentration values of the heavy metals were 18.5, 23.4, 57.5, 78.2 and 3.1 mg/Kg for Pb, Cu, Cr, Zn Cd respectively. The soil is contaminated with Cd as CF and I_geo are both higher than unity. However, the PLI of 0.33 for the entire soil area indicates insignificant pollution. The PERI value of 98.4 which is less than 110 also indicates insignificant ecological risks. The soil area therefore can be used for the intended project of rearing household animals but the Cd level would need to be constantly monitored.

Keywords: Heavy metals, Soil, Pollution, Contamination indices

DOI: 10.7176/JEES/9-1-08