Characteristics of the territory of the Rivne region according to the value of radon flux density out of the soil

This article presents features of pre-Mesozoic Quaternary sediments and soil variations for the territory of the region. Middle-Upper Riphean sediments (sandstones) of the Lower Vendus (tuffs, basalts), represent the Polissia zone on the territory. The Lisostep zone is represented by Devonian sediments (interlayers of argillites, siltstones, and limestones). The soils of the Polissia area formed the mellow sand and moraine deposits and represent the soddy podzolic of the different levels of soil gleying. The soils of Lisostep formed less and loamy soils and they represent mainly grey forest podzolic and low humus chernozem with the marks of soil podzolization. The scale of quantitative and qualitative estimation of constrained ecological risk for the region population is set from lower to a high level with the value of radon current density out of the soil from 0 to 25 mBq/(m2⋅s), medium – from 25.1 to 50 mBq/(m2⋅s), higher than medium from 50.1 to 75 mBq/(m2⋅s), higher than 75 mBq/(m2⋅s). Notably, in the Polissia area, 46.3 % of the population suffers from a medium level of risk and in the area of Lisostep, 23.4 % of the population suffers from higher than medium risk and 4.6 % suffers from high-constrained ecological risk.