Authors : K.O. Igwe, E.N. Onyeike and A.A. Uwakwe
Abstract: Oil spillage has always been a major source of pollution which releases harmful substances into the environment. The concern over pollution of farmland has constituted environmental issues over the year. Most remediation effort is aimed towards reducing hydrocarbon content of soil at the point of impact. In this study, the concentration of TPH, PAH, some inorganic anions and heavy metals (cadmium, nickel, zinc, lead) where determined in soil collected from farm land located around the point of impact of crude oil. The soil TPH ranged from 123.92±3.26 to 934.79±5.26 mg kg-1. The soil PAH ranged from 12.18±1.10 to 86.21±1.80 mg kg-1, chloride concentration ranged from 24.70±0.00 to 399.37±5.77 ppm in surface soil while the subsoil concentration ranged from 29.37±5.77 to 221.03±14.43 ppm, nitrate concentration ranged from 7.40±0.36 to 59.67±1.53 ppm in surface soil while the subsoil concentration ranged from 10.00±0.01 to 43.33±1.53 ppm, sulphate concentration ranged from 16.00±0.00 to 160.00±10.00 ppm in surface soil while the subsoil concentration ranged from 16.00±1.00 to 126.67±5.77 ppm, phosphate concentration ranged from 16.00±0.00 to 28.57±0.12 to 393.33±3.06 ppm in surface soil while the subsoil concentration ranged from 14.37±0.15 to 282.33±2.08 ppm, cadmium concentration ranged from 0.24-0.47 ppm in surface soil while the subsoil concentration ranged from 0.23-0.35 ppm, nickel concentration ranged from 2.20-2.97 ppm in surface soil while the subsoil concentration ranged from 1.07-1.98 ppm. Zinc concentration ranged from 11.58-24.78 ppm in surface soil while the subsoil concentration ranged from 6.00-24.36 ppm. Lead concentration ranged from 0.61-4.25 ppm in surface soil while the subsoil concentration ranged from 0.41-3.73 ppm. The study, therefore showed that the primary method of remediation by petroleum industries in Rivers State may achieve environmental partial clean-up at the oil-impacted site but contaminate a much wider area away from the oil-impacted site.
K.O. Igwe, E.N. Onyeike and A.A. Uwakwe, 2013. Assessment of TPH, PAH, Some Inorganic Anions and Heavy Metal Concentration of Arable Soil Around Crude Oil Spilled Sites in Rivers State, Nigeria. Research Journal of Biological Sciences, 8: 166-173.