[Man and his environment from the perspective of epidemiologist]

The article is an attempt to characterize the human environment from the stand point of the methodology of epidemiological studies. The broad concept of environmental indicates both factor imposing the negative effects on health and also those kinds of exposures that can have modifying influence, either by increasing the likelihood of disease or reducing it. Identified as an important component of the environment in which man lives are other people and emphasized the role of demography in epidemiological studies as part of both the environment and the reference population for studied phenomena.