Monitoring and assessment of dietary exposure to chemical contaminants.

The results of the Global Environment Monitoring System/Food Contamination Monitoring and Assessment Programme (GEMS/Food) and other monitoring programmes for priority contaminants in the diet, including lead, cadmium, mercury, polychlorinated biphenyls, organochlorine and organophosphorus pesticide residues and aflatoxin, are presented. These results are assessed with respect to established acceptable or tolerable intakes for these contaminants. While the assessments generally confirm the effectiveness of government efforts to prevent or reduce food contamination in industrialized countries, better exposure estimates for infants and children and other vulnerable groups should be calculated. In developing countries, little reliable information is available on the occurrence of food contamination. Without such information, the health of hundreds of millions of people may be threatened. For these countries, and especially those that employ older agricultural and industrial technologies, basic food contamination monitoring and assessment programmes should be established for at least those contaminants of priority concern. These programmes form an essential basis for developing effective intervention strategies and for efficient management of health and environment resources. In all countries, accidental and sporadic contamination is an ever present danger and continual vigilance is necessary to protect public health. All countries should identify institutions with the analytical capability to support epidemiological investigations of outbreaks of disease that may be associated with consumption of chemically contaminated food. All countries should participate in GEMS/Food to promote health-oriented, population-based monitoring at the national level.