Journal of Materials & Environmental Sustainability Research (2022), 2(4): 1-18 p-ISSN: 2811-1338; e-ISSN: 2811-132X DOI: https://doi.org/10.55455/jmesr.2022.009 Published by Centre for Energy and Environmental Sustainability Research (CEESR), University of Uyo, Uyo, Nigeria | 1 Original Research Paper Physicochemical properties, total concentration, geochemical fractions, and health risks of trace metals in oil-bearing soils of AkwaIbom State, Nigeria Godwin A. Ebong 1 *, Eno A. Moses 1 , Otobong A. Akpabio 1 , Rosemary B. Udombeh 1 1 Department of Chemistry, University of Uyo, Uyo, Nigeria * Corresponding author: Godwin A. Ebong (g_ebong@yahoo.com, godwinebong@uniuyo.edu.ng) Received: November 7, 2022; Revised: December 16, 2022; Accepted: December 24, 2022; Published: December 31, 2022 © 2022 Centre for Energy and Environmental Sustainability Research, University of Uyo, Uyo, Nigeria Handling Editor: Nnanake-Abasi O. Offiong Abstract: The physicochemical properties, total metal, metal fractions, and related human health problems of metals in oil- bearing soils of Akwa Ibom State were appraised using standard procedures. The study aimed at assessing the effects of crude oil and related activities on the properties of soil including metals (Cd, Cr, Ni, Pb and V), their fractions and associated health problems. Results showed that, levels of parameters were higher in the soils examined than in the control. The entire metals examined, apart from Cd, were within their acceptable limits however; higher than the limits for agricultural soils. Cd and Cr existed mainly in the readily available fraction, while Ni, Pb, and V occurred mainly in the reducible fraction in the studied soils. Conversely, these metals, except Cd, occurred principally in the inert fraction in the control. V/Ni ratio confirmed the soils as oil-forming continents and of organic matter origin. The natural factor, crude oil, and oil-related activities were major sources of soil contaminants. Anthropogenic proportions of metals were more in the soils investigated than in the background soil. The locations were contaminated with metals. Daily intake rates of metals were within their recommended doses except for Pb. The pollution status of the oil-bearing soils and the related human health risks have been revealed. Keywords:Oil-bearing soil; multivariate analysis; soil pollution; metal speciation;trace metals DOI: 10.55455/jmesr.2022.009 1. Introduction The discovery of crude oil in the South-South Region of Nigeria and the related industrial activities thereafter has caused serious environmental degradation in the area for years now. Reports have shown that the land, water, and air environments are under serious threat due to contaminants/pollutants from oil and oil-related activities (Bodo and Gimah, 2020; Julius, 2011; Singh et al., 2020). The existence of crude oil and oil-related activities within the studied region has led to the reduction in the population of fish and extinction of some species of living organisms in the area (Orisakwe, 2021; Ugochukwu and Ertel, 2008). It has also been reported that, the devastating effects of oil and oil-associated activities in the oil producing Region of the country has manifested in rooftops (Bodo and Gimah, 2020; Ismail and Umukoro (2012). The physicochemical properties and soil nutrients within the oil producing Region are also impacted by the availability of crude oil and the associated oil activities (Atuma and Ojeh, 2013; Odjugo and Osemwenkhae, 2009; Ohanmu et al., 2018). Naturally, Nigerian crude oil is known for having high level of toxic metals (Ahiamadu et al., 2021). Consequently, the soil that bears crude oil in Nigeria is expected to also contain elevated levels of these metals (Chinedu and Chukwuemeka, 2018; Thomas et al., 2021). Reports have shown that, oil-bearing soils and oil-related activities