Assessment of Heavy Metals Concentration of Crude Oil Polluted Soil and Water in Some Coastal Communities of Akwa Ibom State, Nigeria

Abstract

The level of heavy metals concentrations of crude oil polluted soil and water was assessed in some coastal communities (Eket, Ibeno, EsitEket and Onna) of Akwa Ibom State, Nigeria using Atomic Absorption Spectrophotometer. The mean values of the heavy metals determined were: Cr(0.1544±0.01), Cd(0.0137±0.00), Pb(0.0340±0.04), Ca(64.9360±1.55), Ni(0.0112±0.02), Cu(0.0164±0.00), Co(0.00), Mn(1.0067±1.54), Fe(0.6526±0.13), Zn(0.1175±0.04) for water samples and Cr(0.5595±0.12), Cd(0.2139±0.17), Pb(0.1559±0.03), Ca(1.7940±0.62), Ni(0.1685±0.02), Cu(0.1398±0.04), Co(0.0180±0.01), Mn(5.7187±1.34), Fe(9.5787±0.89), Zn(0.2626±0.22) for soil samples. The results showed that calcium was very high in water Ca(64.9360±1.55) samples compared to the soil Ca(1.7940±0.62) samples which suggest that the water is hard, though these values were within the WHO standards. Also, cobalt was not detected in water samples. All other heavy metals determined were above the WHO permissible limits for water and soil samples except zinc and copper which were within the acceptable limits. In all, the concentration of heavy metals in the soil samples was observed to be higher than the water samples which might be due to leaching and bioaccumulation. Thus, a further comprehensive study is recommended and also, intervention strategies like remediation, to better the life of the people.