Polycyclic aromatic hydrocarbons and heavy metals in smoked beef: effect of solvents and extraction methods

Abstract

The presence of polycyclic aromatic hydrocarbons (PAHs) and heavy metals in smoked food in appreciable amount is an issue of concern in recent times. The present study focuses on the PAHs and heavy metal contents of smoked beef. The effect of three solvent combinations (n-hexane, dichloromethane and n-hexane:DCM) and two extraction methods (Soxhlet and sonication) on PAHs contents were also assessed. GC-MS was used for the quantification of PAHs while heavy metal contents were analyzed using atomic absorption spectrometer. The concentrations of metals were in the general order: Fe > Zn> Mn > Pb > Cu > Cd. The content of metals was generally lower than the permissible limits based on international standard. Sonication method gave the highest yield of total PAHs (45.15μg/kg) while n-hexane registered the highest extraction efficiency amongst solvents. The concentration of PAHs ranged between 0.09 - 9.90 μg/kg. Benzo[a] pyrene exceeded the 5.0μg/kg maximum limit in some cases. It is necessary to continually check the concentrations of PAHs and heavy metals in food.