ASSESSMENT OF THE TYPES OF POLYCYCLIC AROMATIC HYDROCARBON PROFILE

ABSTRACT

Polycyclic aromatic hydrocarbons (PAHs) are chemical compounds comprised of carbon and hydrogen molecules in a cyclic arrangement. PAHs are found in common fueling material for fish smoking in Nigeria. The aim of this study was to determine the polycyclic aromatic hydrocarbon profile in African catfish (Clarias gariepinus) smoke-dried with selected wood energy sources. This was investigated using charcoal from four different woods; Gmelina arborea (meliana), Hevea brasiliensis (rubber wood), Lophira alata (ekki) and Pentaclethra macrophylla (okpagha). Smoke-drying of the fish was done using the Magbon-Alade smoking kiln and the fresh fish samples served as the control for the experiment. Samples of smoke-dried fish from each treatment were homogenized using the porcelain mortar and pestle; then packaged in labeled air-tight containers prior to extraction. Pure extracts from the samples were subjected to gas chromatography. The results showed that the PAH concentration in fresh fish sample (control) was below detection limit and no PAHs was discovered in the smoke-dried fish samples treated with different wood charcoals. Thus, fish samples smoke-dried using these charcoals do not constitute a health risk, as the PAH contents were undetected and hence, below the maximum levels acceptable by the European Commission. The use of the Magbon-Alade smoking kiln fueled with charcoal possibly contributed to the minimal level of PAHs that infiltrated the fish during the smoking process since the fuel source has already been stripped of most of its PAH contents as much lower quantities of PAHs are found in charcoal than in wood as a result of wood pyrolysis.