Determination of oncological disease risks caused by radon in urban ecosystems of Rivne
O.O. Lebed, A.М. Pryshchepa, O.M. Klymenko, N.S. Kovalchuk
It is supposed that radon in the apartment and the products of its decay facilitate the increase of lung cancer morbidity rate and other oncological diseases risks of total population. The main source of radon getting into apartment (up to 90%) for most buildings is soil gas. For the inhabitants of Rivne, situated on the western hill-side of the Ukrainian crystal shield concentrated with uranium and radium, broken by a complicated system of fracture by which radon easily go up with the help of soil waters and on its own, increasing its concentration in surface soils, is extremely important. The article gives the results of complex determination of average volumetric activity of Radon 222 in the air of low-ground apartments of 48 testing areas of Rivne urban ecosystems, compares the received results with the indices of lung cancer morbidity and mortality of population, that died in the given areas during the period of 2014-2016. The values of additional relative risk concerning the given disease are calculated, using the models of permanent relative risk and GSF (Jacoby Model). It is ascertained that average geometric value of Radon 222 volumetric activity (VA) in the apartments of the ground floors of testing areas under research made up 200 Bk/m3 with standard geometric error 0.7865, average arithmetic value of radon volumetric activity in the air of the same apartments made up 262.5 Bk/m3 with standard error 194.4 Bk/m3. That is evidence of considerable variations of radon level in the air of houses in the territory of Rivne. Maximum measured value of volumetric activity makes up 1000 Bk/m3 and maximum prognosticated value is 1420 Bk/m3. Under 70-years-old radon exposition with volumetric activity 200 Bk/m3, value of additional relative risk make up 0.0446 for the model of permanent relative risk and 0.0633 for Jacobi model, according to the same time period radon exposition with volumetric activity 1426 Bk/m3-0.26 for the model of permanent relative risk and 0.33 for Jacobi model. According to permanent radon exposition in the apartment with volumetric activity 200 Bk/m3 the upper level of adopted individual risk (individual risk border) for the inhabitants of Rivne come approximately at the age of 30-34 when calculated after model of permanent relative risk and at the age of 25-29 when calculated according to Jacobi model.