The Effect of Fish Smoking Methods on Polycyclic Aromatic Hydrocarbons (PAHs) Contamination

Abstract

Fish smoking can contaminate the smoked fish with Polycyclic Aromatic Hydrocarbons (PAHs), as they are formed as a result of incomplete combustion. Fish smokers in Borno State, Nigeria were known to employ three unique methods: A. Earth Oven, B. Traditional Open Tray and C. Drum Kiln Smoking methods. These methods differ in the distance between the combustion (heating) chambers and the fish smoking plates and may contaminate the smoked fish with PAHs. The study aimed to assess the effect of different fish smoking methods on the level of PAHs contamination and its corresponding human health risk. Fish samples of Carias gariepinus were brought directly from fishermen at Alau Dam, Maiduguri. The samples were identified and divided into four groups. Three of the four groups were subjected to a smoking method (A. Earth Oven, B. Traditional Open Tray and C. Drum Kiln), while the 4th group labelled D was used as the control. The smoking was done using Khaya senegalensis wood converted into charcoal by charcoal dealers in the Bakassi area, Damboa Road, Maiduguri. The results further reveal the concentration of 8 out of the 16 priority PAHs compounds detected: Naphthalene (1.02 and 1.03 μg/kg in smoking methods B and C respectively), Methyl Naphthalene (1.01 μg/kg in smoking method B), Acenaphthylene (2.01 and 1.58 μg/kg in smoking methods B and C respectively), Acenaphthene (1.01 μg/kg in smoking methods B), Pyrene (1.00 and 1.02 μg/kg in smoking methods B and C respectively), Chrysene (2.80 μg/kg in smoking method B), Benz (a) anthracene (1.10 and 1.00 μg/kg in smoking methods B and C respectively), Benzo(b)fluoranthene (1.00 μg/kg in both smoking methods B and C respectively). PAHs were not detected in smoking method A (earth oven) or Group D (control).