Distribution, Compositional Pattern and Potential to human exposure of PAHs in Water, Amassoma axis, Nun River, Bayelsa State, Nigeria

This study was carried out to investigate the distribution and contents of sixteen priority polycyclic aromatic hydrocarbons (PAHs) in water from Amassoma axis of the Nun River, Bayelsa State, Nigeria. The PAH contaminations in the river water samples was performed using GC-MS method. The results were similar for all of the three sampling stations. Six LMW PAHs: naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene and five HMW PAHs: fluoranthene, pyrene benzo (a)anthracene, chrysene and benzo(a)pyrene were found. The ∑ PAHs concentration ranged from 0.111mg/L to 0.26mg/L. In this study, PAH fingerprint ratios for determining both petrogenic and pyrogenic (pyrolytic) PAH accumulation in the environment and Toxic equivalency factor (TEF) used to estimate relative toxicity of a PAH compared to that of BaP was employed. The Ph/An ratio for water samples were 0.00, 0.33 and 0.00 in three stations, while associated figures for Fl/Py ratio values were 0.67, 0.83 and 0.50 respectively. Pearson correlation matrice analysis reveals a positive correlation between the PAHs; this could indicate a common source for some of the PAHs, however, some were negatively correlated with each other. This behavior could indicate non-point source. A comparative analysis of PAHs concentrations in the water samples with WHO standards revealed that the results obtained in this study were within the permissible levels, however, carcinogen PAHs present in the water of the Amassoma axis, Nun River may pose a threats to human health.