Water Quality Issues in the Niger Delta of Nigeria: Polyaromatic and Straight Chain Hydrocarbons in Some Selected Surface Waters

Abstract

Surface water samples were collected from mid-Niger Delta, Nigeria, Bayelsa, Delta and Rivers States with high petroleum activities. The impact of these activities on potable water was investigated by determination of polyaromatic and straight chain hydrocarbon contents. The 16 US EPA priority polynuclear aromatic hydrocarbons PAHs, straight chain hydrocarbon (C8–C40), pH, temperature, chloride (Cl−), were determined. Pseudomonas sp, Proteus sp, Bacillus sp, Penicillium sp, Achromobacter sp and Aspergillus sp were also determined. All the parameters were determined using their respective standard methods. Anieze river in Port-Harcourt had six (6) PAHs-Acenaphthene (0.015 mg/l), 1,2-Benzanthracene (0.004 mg/l), Benzo(b) fluoranthene (0.064 mg/l), Benzo(g, h, i) perylene (0.009 mg/l), Dibenzo(a, h) anthracene (0.040 mg/l) and chrysene (0.015 mg/l). Orash river had chrysene (0.017 mg/l) and fluorene (0.109 mg/l). Only Ifie-Kporo river in Delta State had Dibenzo(a, h) anthracene (4.350 mg/l), while none of the water samples from Bayelsa had any of 16 PAHs. Straight chain aliphatic hydrocarbon of the order C8–C14 were not detected in majority of the samples, whereas C15–C40 were detected in most of the samples with highest to lowest concentrations in water samples from Rivers, Delta and Bayelsa States, respectively. Temperatures above 30°C were seen in some water bodies and highest chloride level was seen in Ozubo river (Rivers state) 17,198.00±0.06 mg/l and 15,850.00±0.03 mg/l in dry and rainy seasons respectively. The pH of all the samples are within internationally accepted limits, except Egbo stream (pH 5.53), Olomoro burrow pit stream (pH 5.79) and Ughewhe stream (pH 5.32), all in Delta State; while Orash river (pH 5.22). In view of the negative impact of surface water in the Niger Delta by petroleum activities and its possible public health importance, we recommend water quality monitoring and suggest the possibility of developing a biomarker for determining the age of a particular pollution.