Benoit Schilter, Nestlé Research Center, Lausanne, Switzerland.
Chemical analysis of food has revealed the presence of a multitude of substances occurring over a large range of concentrations, from picog to g levels. Some are intrinsic components of food, including macro- and micro- nutrients, anti-nutrients and inherent toxicants, while others are extrinsic, either added or resulting from natural or industrial sources. In addition, process-related chemicals are formed during processing. So from scientific point of view, food can be assumed as a highly complex mixture of chemicals. To understand the health significance of food chemicals is complex. Many provide but others reduce nutritional value. Some may be associated with beneficial effects. A number have been shown to be harmful, producing toxicity. This is why chemicals must be managed to ensure that food is safe. This is not straightforward. Toxicity depends on the properties of each chemical and toxic potencies spans over 6 orders of magnitude. In this context it appears important to establish priorities. Risk assessment, combining exposure and toxicological information, has been valuable to identify chemicals of concern on which management efforts should focus. Toxicological characterization is a resources intensive process based on feeding experimental animal with high doses of the chemical investigated. Only a limited number of chemicals to which human is exposed have actually been characterized toxicologically. Currently the application of the standard toxicology approach to the untested chemicals is getting increasingly questioned from scientific, feasibility and ethical perspectives. New approaches using in vitro and computational methods are now being developed to tackle these challenges.