Pollution Status and Health Risk Assessment of Polycyclic Aromatic Hydrocarbons in Surface Water, Sediment and Fish from Ezu-River, Anaku, Anambra State, Nigeria

Abstract

The distribution of the sixteen polycyclic aromatic hydrocarbons (PAHs) was studied in surface water, sediment and three fish species (African catfish (Clarias gariepinus), Trout fish (Mormyrus rume) and Hetrobranchus longefilis) from Ezu-river, Anaku, Anambra State, Nigeria. The samples were analysed for PAHs by means of Gas chromatography-mass spectrometry. The results of PAHs showed that, in surface water, the highest concentration was related to benzo(a)pyrene whereas benzo(k)fluoranthene was the most important pollutant in sediment. For the fish samples, Hetrobranchus longefilis recorded the highest concentration in Naphthalene while Anthracene was the most dominant pollutants in Mormyrus rume and in Clarias gariepinus benz(b) fluoranthene was the highest pollutants. The Health and exposure risk assessment was conducted for carcinogenic and non-carcinogenic exposure in adults and children which shows that the cumulative cancer risk and hazard index were within USEPA regulatory standard. Calculated Hazard Index for fish and water samples were less than one and thus be recommended for consumption.