Food contaminants and other adulterating substances are chemicals that may be present in foods at levels that could impact the overall safety and/or quality of foods. These substances can either be inadvertently present in foods or, in some cases, intentionally added for fraudulent purposes. Establishing a prohibition or maximum level (ML) is a form of risk management that may be employed to reduce exposure to a particular chemical contaminant in foods. Canadian prohibitions and MLs for chemical contaminants in food are set out in Part 1 and Part 2, respectively, of the List of Contaminants and Other Adulterating Substances in Foods, which is incorporated by reference into section B.15.001 of Division 15 of the Food and Drug Regulations (the Regulations). Maximum levels are also set out in the List of Maximum Levels for Various Chemical Contaminants in Foods, which is maintained on Health Canada's website. All prohibitions and MLs for contaminants in food are established by Health Canada's Food Directorate based on scientific evidence and in consultation with stakeholders and are enforceable by the Canadian Food Inspection Agency.

Health Canada is proposing to establish a new ML for inorganic arsenic of 0.1 parts per million (ppm) in rice-based foods intended specifically for infants and young children.