Food safety

General information related to chemical risks in food

Last reviewed/updated
22 December 2009

Chemicals are the building blocks of life and are important for many, if not all, aspect of human metabolism. However, human exposure to chemicals at toxic levels, as well as nutritional imbalances, are known or suspected to be involved in causing cancer, cardiovascular disease, kidney and liver dysfunction, hormonal imbalance, reproductive disorders, birth defects, premature births, immune system suppression, musculoskeletal disease, impeded nervous and sensory system development, mental health problems, urogenital disease, old-age dementia, and learning disabilities. Possibly a significant part of these disorders and diseases can be attributed to chemical exposure, and for many (environmental) chemicals food is the main source of human exposure. Consequently, the protection of our diet from these hazards must be considered one of the essential public health functions of any country.

Under the World Trade Organization's Agreement on Sanitary and Phytosanitary Measures, food traded internationally must comply with Codex Standards that are established to protect health of consumers on basis of a sound risk assessment. Such independent international risk assessments are performed by Joint FAO/WHO Expert Committee on Food Additives (JECFA) and Joint FAO/WHO Meeting on Pesticide Residues (JMPR), as well as ad hoc expert meetings to address specific and emerging issues. The experts estimate a safe level of exposure (acceptable or tolerable daily intake ADI, TDI) and estimate the exposure to chemicals from the diet and from specific foods. Such exposure assessments often are based on national data or international data from the WHO Global Environment Monitoring System - Food Contamination Monitoring and Assessment Programme (GEMS/Food).

Based on the risk assessments provided through these expert meetings, the Codex Alimentarius Commission can recommend specific measures, such as maximum limits in foods to assure that exposure does not exceed the acceptable/tolerable level of intake. Other measure can be the development of 'Codes of Practices' to reduce levels of contaminants in food. Also, levels of use for food additives can be recommended, or maximum residue levels for pesticides or veterinary drug residues when applied in accordance with good practices. The scientific advice provided through these expert meetings also often serves directly as the basis for national food safety standards.