Heterocyclic aromatic amines in cooked hamburgers and chicken obtained from local fast food outlets in the Ottawa region

Heterocyclic aromatic amines (HAAs) are formed in protein-rich foods during high temperature cooking such as frying and grilling. Since most HAAs are potent mutagens and almost all are carcinogenic to laboratory animals, their formation in cooked foods is a health concern. In the present study, 31 cooked hamburgers and six chicken preparations were obtained from various fast food outlets in the Ottawa area and analyzed for HAAs. In the developed procedure, ground-up samples were extracted under both acidic and alkaline conditions, cleaned on SPE cartridges, and the concentrations of various HAAs determined using electrospray ionization LC/MS/MS. Deuterium-labelled internal standards of the three most commonly found HAAs (IQ, MeIQx, and PhIP) in such foods were used for quantitation and recovery correction. Varying levels of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) (0.2-6 micrograms/kg), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) (0.1-3.5 micrograms/kg), 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) (0.3-6.9 microgramsg/kg), and 7,8-dimethyl-IQx (2-amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline) (0.1-2.9 micrograms/kg) were detected in most hamburgers, whereas our limited data on the chicken samples (wings, drumsticks, and nuggets) indicated the presence of mainly PhIP (0.1-2.1 micrograms/kg) and MeIQx (0.1-1.8 micrograms/kg). Traces of 4,7,8-trimethyl-IQx (<0.1 micrograms/kg), 3-amino-1,4-dimethyl-5H-pyrido[3,4-b]indole (Trp-P-1) (<0.1-0.3 micrograms/kg), and 3-amino-1-methyl-5H-pyrido[3,4-b]indole (Trp-P-2) (<0.1-0.8 micrograms/kg) were also detected in some samples of hamburgers but not in any of the chicken analyzed thus far. Since hamburger is a popular meal among Canadians, regular consumption of such items may contribute substantially to one's dietary intake of HAAs.