As the number of chemicals used in industrial processes and in everyday life rapidly increases, the need to assess a priori their impact on the human organism and the environment becomes critically important. Two kinds of chemical interactions are of particular concern. Firstly, metabolic

transformations in the human body and other relevant living organisms, and secondly, transformations under external factors (i.e., sunlight, hydrolysis, atmospheric oxidation, temperature, irradiation, electric and magnetic fields). If both types of interactions could be modeled, the impact of any chemical on the biosphere could be predicted and, if necessary, controlled.