Polycyclic Aromatic Hydrocarbon and Metal Concentrations in Imported Canned Maize

Abstract

Concentrations and profile of polycyclic aromatic hydrocarbons(PAHs) and metals (Cd, Pb, Ni, Cr, Fe and Mn) were determined in selected brands of canned maize in the Nigeria market with a view to providing information on the hazards associated with the consumption of these products. The measurement of the concentrations of PAHs was carried out by using a gas chromatography equipped with flame ionization detector (GC-FID) after extraction by ultra-sonication with acetone/dichloromethane and clean-up. The 16 PAH concentrations varied between 45.1 and 335.7 µg/kg. The concentrations of the indicators for occurrence and effects of PAHs in food varied from 3.6 to 114.5 µg/kg for BaP, 6.4 to 168.2 µg/kg for PAH2, 11.8 to 232.7 µg/kg for PAH4 and 19.4 to 327.3 µg/kg for PAH8. The concentrations of metals were determined by using atomic absorption spectrometry after acid digestion. The concentrations of metals in these samples ranged from <0.05 to 0.9 µg/g for Cd; 5.0 to 8.0 µg/g for Pb, 0.8 to 1.7 µg/g for Fe while Cr and Mn were less than the limits of quantification (<0.05 µg/g). The concentrations of Cd and Pb in these canned maize samples were above their permissible limits for foods.