Radioactive elements in natural and drinking water in Ukraine

The radiation aspects of the quality of natural and drinking water in Ukraine are considered. It has been shown that groundwater radioactivity is mainly a consequence of contamination with natural radionuclides and their decay products: ²³⁸U (²³⁴U, ²²⁶Ra, ²¹⁰Pb, ²¹⁰Po) and ²³²Th (²²⁸Ra, ²²²Rn), as well as 40K. The pollution level of artesian wells is determined by such radionuclides as natural U, ²²²Rn, ²²⁶Ra and ²²⁸Ra. Surface and groundwater, which are sources of drinking water supply and located in the area where radiation objects are located, must be monitored for the presence of technogenic radionuclides of ⁹⁰Sr, ¹³⁷Cs, as well as ³H. The hygienic standards for the content of radionuclides in drinking water are compared. The results of a radiological analysis of sources of drinking water supply in Kyiv — Desna and Dnipro rivers, underground wells of the Senoman and Jurassic horizons are presented. It was found that the content of tritium and other standardized radionuclides in drinking water is significantly lower than the maximum permissible concentration and are at the level of background values. A characteristic of the migration of radionuclides in the environment, taking into account the physicochemical forms of their occurrence, is given. The forms of the presence of ³H, U(VI), Th(IV), ²²²Rn, ¹³⁷Cs, and ⁹⁰Sr in an aqueous medium, which determine the mobility of radionuclides and their potential effect on living organisms, are examined in detail. It is shown that the physicochemical forms of the existence of natural and technogenic radionuclides in the aquatic environment determine their migration in the environment, and therefore their potential impact on living organisms. Based on the analysis of scientific literature data, an assessment of the radiation safety of drinking water supply sources in Ukraine was made in accordance with current regulatory documents for drinking water. The results of a radiological analysis of the surface and underground drinking water sources in Kyiv indicate that all indicators are within acceptable values. (author)