Authors : Osei Akot and Ernest Abankwa
Abstract: Heavy metals are potentially toxic to humans and the environment. Metal toxicity depends on the chemical forms in which they exist. In this research, an investigation was conducted to study the contamination and speciation of some heavy metals (Cu, Zn, Pb and Cu) in sediments from the Owabi reservoir in Kumasi, Ghana. The mean concentrations of Pb and Zn were higher than the Continental Average Shale (CAS) and were beyond the Threshold Effect Level (TEL), implying contamination of these metals in the sediments. This observation was also confirmed by geoaccumulation index calculations. Canonical correlation analysis revealed that leaching of Zn is associated with pH while co-precipitation of Fe and Pb is also associated with EC. Speciation analysis showed significant amount of Zn Cu and Pb were available in the Fe-Mn fractions. But major amount of Fe was found in the residual fraction. The amount of Zn and Pb present in the bioavailable from have the potential to induce ecological risk. The results stresses that discharge of untreated waste into streams serving the reservoir should be avoided to reduce contamination since the contaminants found in this research are mainly release into the environment through human activities. Factor analysis showed that site S1 and S3 are the most polluted sites.
Osei Akot and Ernest Abankwa, 2014. Heavy Metals Contamination and Speciation in Sediments of the Owabi Reservoir. Environmental Research Journal, 8: 10-16.