International Journal of Research and Innovation in Applied Science (IJRIAS) | Volume VII, Issue VI, June 2022 | ISSN 2454–6194
Funkeye K. Tubotu, Patience O. Agbaire
Department of Chemistry, Delta State University, P.M.B. 1, Abraka, Nigeria
Abstract – This study aimed to determine the levels of heavy metals in the upper soil of Obuguru and Burutu communities in the Niger Delta. From both communities, twelve (12) composite soil samples were collected. The analysis of heavy metals {performed with an Atomic Absorption Spectrophotometer (AAS)} revealed that Fe had the highest concentration in all soil samples studied. The general order from the highest concentration of heavy metals to the lowest was Fe > Mn > Zn > Ni > Cd > Cr > Pb > Cu in Obuguru and Fe > Zn > Mn > Ni > Pb > Cd > Cu > Cr in Burutu. Cadmium (Cd) was found to be the major metal pollutant in the soil of the study area. The concentrations of copper (Cu) and chromium (Cr) were below the department of petroleum (DPR) target values for soil, while the concentrations of the other metals studied (Zn, Pb, Ni, and Co) varied between below and above the target limit. The results of the analysis of the correlation matrix show that the metals in the study area have different degrees of relationship.
Keywords: Anthropogenic source, Geo-accumulation index, Enrichment factor, Background concentration, Target value.
I.INTRODUCTION
Heavy metals are chemical elements with an atomic mass greater than 20 and specific gravity greater than 5 g/cm3 [1], [2]. These metals are typically present in trace concentrations (ppb range to less than 10 ppm) in different environmental matrices and as such, they are also regarded as trace elements [3]. Generally, the soil is regarded as the ultimate sink for these metals [4], [5]. Heavy metal concentration in soil is dependent upon the adsorption properties of soil matter. Factors such as pH, conductivity and moisture content mainly influence the solubility of heavy metal ions in soil [5], [6].
The anthropogenic sources of heavy metals in the environment mainly include industrial emissions, such as those from transportation, coal combustion, and fugitive particulate emissions [5]. Since the majority of anthropogenic pollutants are released into the atmosphere before being deposited on the soil surface [5], [7], metals such as Cadmium (Cd), Copper (Cu), Lead (Pd) and Zinc (Zn) can be good indicators of contamination in topsoils because they appear in gasoline, oil lubricants and industrial incinerator emissions [8].