Evaluation of hamburgers and hot dogs for the presence of mutagens

Food products derived from heat-treated (fried, broiled, baked) meat may contain traces of mutagenic heterocyclic amine contaminants, some of which are proven carcinogens in rodents. To confirm their presence and range in Canadian foods, and estimate the average human intake of these types of mutagens from frequently consumed heat-processed foods, several commercially prepared fried-beef patties (hamburgers) and hot dogs (weiners) were analysed for their mutagenic capacity. The mutagenicity of the extracts was tested in the Salmonella/microsome assay using strain TA98 with metabolic activation. 16 samples of hamburgers and 14 samples of hot dogs, randomly obtained from ‘fast food’ commercial establishments; or street vendors, were used in this survey. The mutagenic activity of these samples ranged from very low to 1042 revertants/g equivalent for the hamburgers and from non-detectable to 4875 revertants/g equivalent for the hot dogs. The average values were 199 and 424 revertants/g for the hamburgers and hot dogs, respectively. The wide range in mutagenicity was found even for the same type of product obtained from the same outlet at different times. This indicates possible inconsistency in cooking procedures during the preparation of these products. It also shows the difficulty in accurately assessing the intake of mutagenic heterocyclic amines from hamburgers and hot dogs prepared in ‘fast food’ outlets.