title: Assessing the cancer risk from foods.
abstract: Assessing the carcinogenicity of a compound and then determining what dosage is appropriate for human beings is a complex process. Carcinogens act either by altering deoxyribonucleic acid (DNA) or by promoting the growth of already altered cells. Carcinogenicity is evaluated with the use of structural analysis, in vitro mutagenesis assays, epidemiological findings, and dose-response studies in laboratory animals. In the animal studies, high doses are administered. Once a compound is found to be carcinogenic, the dose that will pose an acceptable cancer risk to human beings--one in a million--must be extrapolated from the high-dose data. This virtually safe dose (VSD) will be the allowable dosage for human contact. The extrapolation from high-dose animal studies to a VSD for human beings is based on the models for carcinogenic mechanisms. Debate exists as to how many interactions with DNA the carcinogen must have to initiate neoplastic growth and whether there exists a threshold for carcinogenic action below which there is no risk of cancer. The extrapolation model that is chosen greatly affects the VSD. Knowing how this extrapolation to a VSD is done will help dietitians better understand how allowable levels for carcinogens in foods are determined.
mesh_terms: D001711:Biotransformation; D002273:Carcinogens / Q000032:analysis*; D004305:Dose-Response Relationship, Drug; D005504:Food Analysis; D006801:Humans; D007700:Kinetics; D008962:Models, Theoretical; D009152:Mutagenicity Tests; D011634:Public Health; D012306:Risk
chemical_list: D002273:Carcinogens