Pah Content of Clarais gariepinus Harvested from Ekulu River, Eastern Nigeria Contaminated with Effluents Generated from a Roofing Sheet Industry Risk Impact Assessment

Abstract

Aim: This study evaluated PAH content and health risks associated with consuming Clarais gariepinus (cat fish) from Ekulu Rivers, in Enugu, Nigeria fed with roofing sheet company effluent. Place and Duration of Study Design: Ekulu River, the largest body of water in the city of Enugu in Enugu State, south-eastern Nigeria, is a 25-kilometer long river (16mi) and it originates in the same city as well. The city is located on latitude 06o 21o N and 06o 30o and longitude 07o 26o E and 07o 37 Eo. Methodology: This analysis was conducted with the use of Gas Chromatography – Mass Spectroscopy (GC-MS) machine equipped with Flame ionization detector (FID). The health risks were evaluated by the mathematical models stipulated by USEPA and WHO. Results: The PAHs identified from the Clarias gariepinus samples were Acenaphthene, Acenaphthylene, Naphthalene, Fluorene, Phenanthrene, Anthracene, Flouranthene, Pyrene, Benzo(α)pyrene and Benzo (g-h-i)perylene. Benzo(α)pyrene and Benzo (g-h-i)perylene were predominant. The quantity of PAHs detected in all fish samples including the control ranged from below detectable limit (BDL) through 0.001 to 0.0786mg/kg. The LMW PAHs detected were 60 % while the HMW PAHs were 40 % of the total PAHs in isolated. The total PAH concentration observed from the different point locations were 0.1003 mg/kg, 0.0977 mg/kg, 0.1102 mg/kg and 0.0414 mg/kg for the downstream, upstream, POD and control respectively. The HQ and HI obtained in all point locations were < 1. The ILCR of all the PAHs detected were in the range of 10-5 to 10-9.  The benzo (α) pyrene in cat fish obtained from the POD has the most carcinogenic potency and also recorded the maximum limit (5E -03 mg/kg). Conclusion: it is pertinent to enlighten the fish consumers and mongers on the dangers posed by the consumption of fish from Ekulu River and also caution industries with injudicious effluent disposal into water bodies.