Effects of heat sources on the levels of polycyclic aromatic hydrocarbon in selected fish samples from Ogidingbe (Escravos Estuaries)

Abstract

The riverine areas of the Niger-Delta region of Nigeria are popularly known for their smoked fish from both fresh and salt water. To the people living in these areas, smoking is a method of preservation as the fish is known to undergo spoilage within 8 h of harvest from its natural habitat; though not without the potential health hazard associated with smoked foods. During smoking, polycyclic aromatic hydrocarbons (PAHs) and its carcinogenic derivatives are produced. Two species of locally consumed fish: Clarias gariepinus and Micropogonias undulantes were used for this study. The M. undulantes were collected from the creeks and estuaries of Ogidigbe and the C. gariepinus from a local pond, Ereyi farms, in Benin City. They were both analyzed for PAHs level in both the fresh and dried form. Comparison of the PAHs level was also done for various dried samples using four different drying methods. Extraction of the PAHs were carried out using solvents by ultrasonication, clean-up was done using solid phase extraction and thereafter analyzed for 16 US EPA PAHs using gas chromatographyflame ionization detector (GC-FID). The results show that drying with mangrove wood charcoal gave the highest PAHs level and it was for samples harvested from the Escravos Estuaries.