POLLUTION LEVEL DETERMINATION USING CHEMICAL SPECIATION IN THE VICINITY OF PETROLEUM PROSPECTING AREAS IN SOUTHERN NIGER DELTA

Abstract

Chemical partitioning was carried out on some heavy metals in soils at Ubeji, Ekpan, Egbokodo, Ifie and Jeddo. All are towns located within the vicinity of petroleum processing areas in Delta State. Heavy metals investigated were iron, manganese, cadmium, copper, lead and zinc; with a view to assess the speciation pattern and the fraction of abundance in the environment; thereby likely to pollute the environment in the foreseeable future. Result showed that iron is more predominant in the residual (F5) and organic fractions (F4), cadmium in the residual fraction (F5), copper in Fe-Mn oxide (F3) and carbonate (F2) fractions, manganese in residual (F5) and Fe-Mn oxide (F3) fractions; while lead and zinc in Fe-Mn oxide (F3) and carbonate (F2) fractions. From the results obtained for the two seasons, most of the metals have high abundance in the residual fractions, indicating lithographic origin and low bioavailability of the metals under investigation. The mobility factor is in the order: Pb > Zn > Mn > Fe > Cd > Cu in the wet season; and Zn > Pb > Mn > Cd > Fe > Cu in the dry season. While the average mobility factor calculated for the metals is in the order: Pb > Zn > Mn > Fe > Cd > Cu. Result shows that lead and zinc are heavy metals to watch and regulate so as to prevent any form of environmental disaster in the future. Keywords: Chemical speciation, heavy metals, mobility factor, petroleum processing