The Influence of Natural Sources on Radiation Exposure Levels in the Population of the Arkhangelsk Region

Abstract

Introduction: The issue of radiation safety in terms of population exposure to natural sources of background radiation remains relevant since, according to the results of numerous studies, among all sources of ionizing radiation the natural ones contribute the most to the population exposure worldwide. Our purpose was to assess the contribution of natural sources of background radiation to the individual effective dose of the population of the Arkhangelsk Region. Materials and methods: We measured residential indoor and outdoor gamma dose rates and the residential indoor equivalent equilibrium volumetric activity of radon isotopes. We also analyzed data of statistical form No. 4-DOZ “Information about population exposure doses attributed to the natural and anthropogenically altered background radiation” and radiation hygiene passportization conducted in 2008–2017 by cities and districts of the Arkhangelsk Region and estimated long-term average indicators of the individual effective dose of radiation and chain indicators of the growth rate. Results: We established that the internal exposure to radon isotopes (46.8%) and external terrigenous exposure (23.6%) contributed the most to the individual effective dose due to natural sources in the population of the Arkhangelsk Region. In 2008–2017, the individual effective dose attributed to natural sources was 2.50 mSv/yr, to external exposure – 0.59 mSv/yr, and to internal exposure to radon isotopes – 1.17 mSv/yr. The analysis of average values of the equivalent equilibrium volumetric activity of radon isotopes and the gamma radiation dose rate in residential buildings of various type (wooden, single-story stone and multistory stone) in the Arkhangelsk Region supported the conclusion about the significant contribution of the former to the individual effective dose due to natural sources. Conclusions: We established the contribution of natural sources of ionizing radiation to the total doses of the population.