Evaluation of Polycyclic Aromatic Hydrocarbon Content of Selected Fin and Shell Fish from Named Rivers in Ogoniland, Rivers State, Nigeria

Abstract

Polycyclic aromatic hydrocarbon (PAH) content in selected fin and shell fishes from Bodo and Kaa in Ogoniland were studied. PAH was determined by Gas chromatography, using Texas Natural Resource Conversion Commission, Texas (TNRCC TX) method. There was a total of 16 PAHs detected in the samples from the two sites, test site (Bodo) and control site (Kaa). Similar PAH accumulations were observed in the four species, but the concentrations of the PAH accumulations were different. For samples from Kaa, Mullet showed the highest total mean concentration of PAHs followed by Sompat grunt, Tilapia and the least was Shrimps. However, for samples collected from Bodo, Tilapia showed the highest total mean concentration of PAHs, followed by Sompat grunt, Shrimps, and the least Mullet. These findings were not definitive as to the source of the PAH, seemingly suggesting various or multiple sources of PAHs contamination in the studied sites. These variations may be attributed to their feeding habits. The mean and standard deviations for PAHs from the test site ranged from 0.08±.000b to 23.7±.473b, 0.05±.001b to 7.74±.346b, 0.02±.001b to 9.48±.002b, 0.07±.000b to 11.0±.029b for Tilapia, Mullet, Shrimps and Sompat grunt respectively and 0.18±.006a to 6.56±.064a, 0.08±.000a to 11.8±.555a, 0.05±.002a to 3.11±.036a, 0.05±.002a to 5.12±.059a for samples of Tilapia, Mullet, Shrimp and Sompat grunt respectively from the control site. In conclusion, the calculated potency equivalence concentration (PEC) for all the tested aquatic species collected from Kaa and Bodo were all above the screening value (SV) suggesting that the consumption of these aquatic species from the test and control site at a rate of 68g/day in an adult of about 60kg will expose the individual to a potential risk of cancer.