Food safety

Global Environment Monitoring System - Food Contamination Monitoring and Assessment Programme (GEMS/Food)

GEMS/Food Total Diet Studies

Toxic chemicals and nutritional imbalances may cause serious health problems, many of which are irreversible and chronic. Elevated lead levels in children can result in delayed mental and physical development and learning deficiencies. Persistent organic pollutants, the so-called POPS, are associated with devastating effects on wildlife, including wasting syndromes, shrinking populations, birth defects such as missing eyes and deformed reproductive organs, and behavioural disorders. In addition, it is estimated that the global economic and trade burden from these contaminants in food totals many billions of dollars annually. It is therefore essential to have accurate information on people's actual dietary exposure to toxic chemicals. This is the main intent of total diet studies (TDS).

Total diet studies are the primary sources of information on the levels of various contaminants and nutrients in foods for human consumption. In addition, TDS results can be an indicator of environmental contamination by chemicals, such as POPs, and can be used to assess the effectiveness of specific risk management measures. As the presence of toxic chemicals in our world and their potential presence in our food increases, it becomes increasingly important to assess human exposure to background concentrations of a large number of chemicals in the diet. The responsibility and obligation to make these assessments usually rests with national health authorities. Total diet studies are internationally recognized as the least expensive way to estimate the average dietary intakes of toxic and nutritional chemicals for a range of population groups.

GEMS/Food has for many years supported the concept of TDS as one of the most cost effective methods for generally assuring the dietary intake of chemicals is within safe limits and for setting priorities for further study. WHO in collaboration with counterpart national agencies has sponsored four International Total Diet Studies Conferences/Workshops, including Kansas City in July 1999, Brisbane in February 2002, Paris in May 2004 and Beijing in October 2006. In addition, WHO sponsored regional TDS workshops in Buenos Aires in July 2002, Brno/Prague in November 2002, Cairo, Egypt in October 2007 and Jakarta, Indonesia in December 2007.