Comparative assessment of TPHs and bioaccumulation in some fresh fish species in the Qua lbeo River of Eket of Akwa lbom State in Nigeria

Abstract

This investigation was carried out in four different locations mapped out along the river bank. Twelve water samples were collected and six different fresh fish species that are frequently consumed were caught. They include: African red snapper (Lutjanus agennes), Yellow tail (Seriola lalandi), Barracuda (Sphyraena barracuda), Atlantic Croker (Micropogonias undulates), Catfish (Clarias gariepinus) and Tilapia (Oreochromis niloticus). Samples were subjected to screening using gas chromatography and flame ionization detector instrument. Results revealed presence of total petroleum hydrocarbon (TPH) contaminant in all the fish samples and varies with species significantly at p >0.05. The profound TPH compound is Nonane with molecular formula C9H20. 9 x 10-9 mg/l was adapted as Nonane concentration in water samples. Nonane concentration in fish samples showed African red snapper 3.9565±4.64648 mg/l, Yellow tail 8.7243±2.15546 mg/l, Barracuda 6.2555±0.48889 mg/l, Atlantic Croker 9.3866±0.42208 mg/l, Catfish 4.1973±1.52959 mg/l and Tilapia 6.0039±0.96487 mg/l respectively. The bioaccumulation factor varies in fish species, where the Yellow tail have higher bioaccumulation factor 969,369061, followed by Barracuda 695,067209, Tilapia 667,101072, Catfish 466,368366, African red Sniper 439,616275 and Crocker fish 104,2956024 respectively. This investigation reveal considerably the extent of bioaccumulation of TPH contaminants in aquatic animal models and making unsafe for consumption as some fishes bio-accumulate nonane beyond permissible limitBangladesh J. Sci. Ind. Res. 51(2), 147-154, 2016