The influence of baking fuel on residues of polycyclic aromatic hydrocarbons and heavy metals in bread

The influence of fuel type used to bake bread on the spectrum and concentra tions of some polycyclic aromatic hydrocarbons and heavy metals in baked br ead was assessed. Bread samples were collected from different bakeries oper ated by either electricity solar, mazot or solid waste and their residue co ntent of PAHs and heavy metals was assessed. The total concentration of PAH s detected in mazot, solar, solid waste and electricity operated bakeries h ad an average of 320.6, 158.4, 317.3 and 25.5 mug kg(-1), respectively. Sam ples collected from mazot, solar and solid waste operated bakeries have had a wide spectrum of PAHs, in comparison to that detected in bread samples c ollected from electricity operated bakeries. Lead had the highest concentra tions in the four group of bread samples, followed by nickel, while the con centrations of zinc and cadmium were the least. The concentration of lead d etected in bread samples produced from mazot, solar, solid waste and electr icity fueled bakeries were 1375.5, 1114, 1234, and 257.3 mug kg(-1), respec tively. Estimated daily intake of PAHs based on bread consumption were 48.2 , 28.5, 80.1, and 4.8 mug per person per day for bread produced in bakeries using mazot, solar, solid waste and electricity, respectively. Meanwhile, the estimated daily intake of benzo (a) pyrene were 3.69, 2.65, 8.1, and 0. 81 mug per person per day for bread sample baked with mazot, solar, solid w aste and electricity, respectively. The daily intake of lead, based on brea d consumption was 291, 200.5, 222, and 46.31 mug per person per day for bre ad sample baked with mazot, solar, solid waste and electricity respectively . The present work has indicated the comparatively high level of daily inta ke of benzo (a) pyrene and lead in comparison to levels reported from many other countries and those recommended by international regulatory bodies. I t is probable that residues detected in bread samples are partially cereal- borne but there is strong evidence that the process of baking and the gases emitted are responsible for most of the contamination load: (C) 2000 Elsev ier Science B.V. All rights reserved.