We propose a possible version of the concept of the construction of an ecological risk criterion for populations and analyse problems of its practical realization.The progress in the scientific and technological revolution at this stage is accompanied by a considerable increase in the spectrum of harmful factors in the environment. In spite of the obvious danger of environmental pollution the sanitary standards are not infrequently violated, and the impact of the new harmful factors on human health, as a rule, needs a prolonged and detailed study. This primarily refers to genetic changes which have no threshold effect and manifest themselves with a certain, sometimes considerable, lag. This problem becomes even more important because mutation changes often lead to hereditary pathology. Having originated once, the pathological mutations persist over prolonged periods and are passed on from one generation to another.A lot of publications both of a theoretical and of an experimental character deal with the development of a mutageneity estimate [2,6]. Attempts have been made to consider the impact of environmental mutagens on cells, organisms, and populations in the context of genetics and sanitary with the aim to develop and use the system of genetic monitoring in practice. Moreover we should emphasize that on the background of fundamental investigations in this area [7,8] the so-called ecological risk criterion for the people is used in increasing frequency in the scientific literature and science fiction. The use of this criterion, which sometimes has no distinct meaning [4], implies the realization of optimal measures intended to improve the ecology and human health in concrete regions.The aim of this research is to develop the concept of the construction of an ecological risk criterion for populations and quantitative methods of its determination under real conditions.