Total petroleum hydrocarbon content in surface water and sediment of Qua-Iboe River, Ibeno, Akwa-Ibom State, Nigeria

Abstract

The total petroleum hydrocarbon content in surface water and sediment of Qua Iboe River, Akwa Ibom State, Nigeria was assessed by randomly collecting samples from five sampling points of the study area and from a control site. The samples were extracted with dichloromethane (DCM) by liquid-liquid partition for water and Soxhlet extraction for sediments followed by subsequent clean up on column chromatography and analyzed by gas chromatography-flame ionization detection (GC-FID) for the determination of total petroleum hydrocarbons (TPH). The results showed variation of total petroleum hydrocarbon (TPH) content from 90 to 250 μg/L in the water and 270 to 830 mg/kg in the sediments, with mean value of 168.33±59.29 μg/L and 606.83±229.48 mg/kg respectively. The average amount of TPH in the water samples collected from all the sampling points was generally lower than the EU standard limit of 300 μg/L. However, the levels in the sediments exceeded the EGASPIN target value (50 mg/kg) for mineral oil but were below the intervention value (5,000 mg/kg), this indicates a serious impact of oil industrial activities on the area. Hence, our findings have indicated evidence that Qua Iboe River is under pollution threat and underscore the need for early remediation if adverse health defects are to be prevented.

Keywords: Total petroleum hydrocarbon, GC-FID, surface water, sediments