Consumers are exposed to a diversity of chemicals in all areas of life. Air, water, soil and food are all unavoidable components of the human environment. Each of those elements influences the quality of human life, and each of them may be contaminated. We are exposed to toxic or potentially toxic compounds in many ways in our daily lives and toxicology is clearly a subject of great importance for society. This becomes apparent when we look at the types of poisons and the ways in which we are exposed to them. Indeed, the categories cover virtually all the chemicals one might expect to encounter in the environment. After consideration of this, one might well ask Are all chemicals toxic? Phrase as an answer: There are no safe chemicals, only their safe use. Xenobiotics are defined here as those compounds, both organic and inorganic, produced by human beings and introduced into the environment, as well as into the food chain at concentrations that cause undesirable effects. Xenobiotics in the food chain are monitored in two forms: by testing - the objective of which is to discover unsuitable foodstuffs in the consumer`s network, and by monitoring - to obtain objective information about environmental components contamination and to harmlessness health of available foodstuffs.