Environmental Risk Analysis of Aged Soil in an Environment Impacted by Nigerian Crude Oil

Abstract

This investigation focuses on the degree of pollution brought on by the prospecting and extraction of crude oil, with a focus on some heavy metals (lead, chromium, copper, nickel, and arsenic), their associated ecological effects on the environment (soil), and the potential risks these heavy metals pose to both human health and the environment. The soil collected from five crude oil-polluted sites in the Eastern and Western oil operation blocs in the Niger Delta was preserved, transported, and stored using the standard scientific method. These samples were further digested for heavy metals by the acidification method, followed by the sonication approach. To assess the digested samples both qualitatively and quantitatively, the inductively coupled plasma optical emission spectrometry (ICP-OES) device was used. The results obtained from the analysis revealed that some classified heavy metals were discovered to be over the detection thresholds, except for zinc (Zn), cadmium (Cd), and vanadium (V). The metals and metalloids under study which were evaluated for their ecological risk that constitutes an environmental menace in the crude oil-impacted soil are lead (Pb) and arsenic (As). Therefore, this shows a high risk of using such land for food production, as these metals and metalloids could find their way into the food networks, putting animals, people, and benthic organisms at serious risk. Hence, it is necessary to carry out proper remediation on the soil to mitigate the metals and metalloids to an acceptable or permissible level before any farming or agricultural activities.