Radiation exposure of population due to careless use of radioactive raw materials in the Urals

Basing on the results of estimating the external dose of gamma-irradiation in private houses in village Kostousovo the collective exposure dose was calculated. Population of the village is 430 people. Taking into consideration that population spends indoors about 7000 hours per year this dose equals to 56 cSv/year. Besides, 77% (43 cSv) of this dose is formed by the sources of natural gamma-irradiation, whereas 23% (13 cSv) - by technogenic concentrations of natural radionuclides (addition). Maximum individual effective dose by gamma-irradiation is a private house is 16.2 mSv/year. The collective exposure dose formed as the result of inhalation penetration of thoron and daughter products is equal to 32 cSv/year. Besides, 81% of this dose (26 cSv) is caused by exhalation of thoron from the building materials and soil with natural concentration of 232Th, and 19% (6.0 cSv) - by Th exhalation from building materials with elevated concentration of natural radionuclides (addition). Maximum individual effective dose in a private house constitutes 3.8 mSv/year. In the result of penetration of radon and daughter products the annual collective dose (59 cSv) is formed. (author)