Subject and tasks of toxicology. Types of pollution. Definition of poison. Doses in toxicology. The concept and the effect of low doses. Relationship between dose and response in the body and potential adverse health effects. Pathways of entry and fate (metabolism) of poison in the body. Transport and distribution of toxic substances in the body. The concept of detoxification. Excretion of toxic substances. Mechanisms of toxicity: interactions with cellular macromolecules, with receptors, interaction of xenobiotics with ionic transducers, homeostasis disorder. Inhibition of enzymatic activity and inhibitors. Biomarkers of toxicity. Target organs of toxicity, toxic effects of xenobiotics on the nervous system, cardio-vascular system, kidneys, liver, skin, reproductive system. Study of basic principles and measures of prevention as well as poisoning therapy.