Bulletin of Medical and Biological Research

Summary. Among the cities of Ukraine, in terms of population and parametric characteristics of man-made impact on urban ecosystems, the city of Rivne stands out. Excesses of various mutagens are regularly recorded in its atmospheric air. In view of this, there is a need to control the processes of air pollution in the city, study the nature of mutagenic substances, prevent the growth of man-made pollution, and find means and methods to protect living organisms from mutagenic effects. The aim of the study – to conduct a bioindication of the urban ecosystem of Rivne on the indicators of cytogenetic monitoring. Materials and Methods. To assess the environmental situation against the general mutagenic background, we used a rapid screening method – micronucleus test (MN test). To detect cells with micronuclei, smears were taken from the oral mucosa of 167 preschool children (6–7 years old) living on 12 test sites. Sampling was performed under sterile conditions, from the right, left cheek and lower lip. Analysis of the prepared cells was performed using a microscope. 64950 epithelial cells of the mucous membrane were studied. Results. According to ecological maps, the territory of the city, which is within III, IV, IX, X, and XII test sites, has a "low" level of genetic damage, which determines the "reference" ecological situation on a mutagenic background. Such characteristics allow us to assess the state of the urban ecosystem in this area of ​​the city as "favorable". However, the analysis of the situation on some test sites allows us to note that the northeastern (III and IV test sites) and the south-eastern (XII test site) parts of the city have slightly higher rates of genetic damage compared to the south-western (IX and X test sites) part. The rest of the test sites have a "below average" level of genetic damage, which causes a "satisfactory" environmental situation with a mutagenic background and an "alarming" state of the urban ecosystem. At the same time, the highest values ​​of the MN test of epitheliocytes of preschool children are characteristic of the north-western (I test site) and south-eastern. The obtained dependence and high coefficient of determination (0.35) indicate a significant relationship between the MN index and pollen sterility of indicator plants, which were performed on similar 12 test sites. Nevertheless, it should be noted that the vulnerability of pollen grains of bioindicator plants was significantly higher (in terms of damage) compared to the MN index, which is explained by the higher resistance to environmental factors of children compared to pollen grains of indicator plants. Conclusions. Analysis of research results indicates that the urban ecosystem of Rivne is at a level "below ave­rage" of genetic damage, "alarming" in the state of the biosystem, and "satisfactory" in the mutagenic background

epithelial cells, micronucleus test, cytogenetic damage, bioindication