Lung cancer mortality and radon exposure in Russia

The association between the lung cancer and indoor radon exposure in Russian population was investigated. The average indoor radon concentration for each region was estimated using the annual reports issued by the Saint-Petersburg Ramzaev Research Institute of Radiation Hygiene for the period 2008–2013. The average standardized lung cancer mortalities among males and females were estimated using the reports of the Moscow Hertzen Cancer Research Institute for the period 2008–2012. The relative risk (RR) was estimated as a ratio between the average mortality within seven exposure intervals and background mortality. The slope factors of linear dependence between the indoor radon exposure and lung cancer RR are 0.026 (−0.11÷0.17) and 0.83 (0.52–1.12) per radon concentration 100 Bq/m3 for males and females, respectively (with 90% confidence interval). The obtained results can be explained by the confounding effect of tobacco smoking. Significant excess risk of lung cancer in female population can be associated with radon exposure and low prevalence of smoking

Problems in radon measurements in context of epidemiological studies

Epidemiological case control study is considered to be primary instrument to investigate the relationship between population indoor radon exposure and risk of lung cancer. A number of such studies had been completed in last 15 years and others are running now. Considering indoor radon and progeny some specific efforts should be undertaken to assess the exposure. While the lungs exposure after inhalation arises mainly due to radon progeny, in the case of the radon gas measurements application the researchers have to address the disequilibrium between radon and radon progeny. It is widely accepted by researchers and approved by ICRP that worldwide average value of equilibrium factor is 0.4 though real equilibrium factor value can deviate significantly from average. Temporal variation of indoor radon concentration complicates the evaluation of exposure as well. Three types of variation can be emphasized: diurnal, seasonal and long time. Experimental and modeling investigation of radon entry shown that pattern of indoor radon temporal variation firmly depends on relationship between entry rates of primary radon sources (diffusive and advective) and influencing factors are construction characteristics, climatic condition and life style. To find appropriate parameters describing radon disequilibrium and temporal variation it is necessary to perform special investigation in the representative sample of houses

Combined analysis of onco-epidemiological studies of the relationship between lung cancer and indoor radon exposure

Objectives: Recent results of epidemiological and medical statistics studies of lung cancer and indoor radon in different regions of the world make a relevant new combined analysis of residential exposure health effects. In particular, new data were obtained by means of a meta-analysis of case-control studies as well as taking into account a confounding effect of human papillomavirus infection in studies of geographically aggregated data. Materials and methods: Two sources of epidemiological data are considered: (1) studies of ecological design and (2) case-control studies. Ecological studies included the analysis performed for the USA counties and Russian oblasts with adjusting for the main confounders. Data on the case-control studies were gained from the meta-analysis of 31 individual studies with a weighting of obtained odds ratios according to the quality of radon exposure reconstruction and size of the reference group. Estimations of lung cancer excess relative risk (ERR) associated with indoor radon exposure are combined. Results: Two types of epidemiological study design provided generally consistent EER estimations. The combined value of ERR due to radon exposure is 0.14 (90% CI: 0.10–0.18) per 100 Bq/m3 . Conclusion: Available geographically aggregated data in regions of Russia and the United States and the meta-analysis of case-control studies conducted in a large number of countries confirm the association of lung cancer with indoor radon exposure

A comparison of human exposure to natural radiation and DU in parts of the Balkan region

The paper presents the field results from six selected rural communities in the Southeast (Kalna), South (Niska Banja, Gornja Stubla, Borovac) and West (Uzice, Han Pijesak) parts of the Balkan region, where general population exposures to unmodified and technologically enhanced natural radioactive material (TENORM), including ammunition containing depleted uranium (DU) or reprocessed DU as well as indoor high radon, have been investigated. Since the only definitive evidence of DU contamination in soil samples could tell the disruption of the natural isotopic abundance of U-238 and U-235, it is important to distinguish between different sources of radiation burden to the population involved. The results of this work confirm that there is a constant need for developing comprehensive information about the spatial distribution of exposures in an adequately fine geographical grid, and for the accumulative dose estimation up to the present that clearly presented the uncertainty ranges and probability distribution of the estimated individual and population doses. (c) 2004 Elsevier B.V. All rights reserved.6th International Conference on High Levels of Natural Radiation and Radon Areas, Sep 06-10, 2004, Kinki Univ, Osaka, Japa

Indoor radon measurements in Kosovo and Metohija over the period 1995-2007

The paper deals with the results of the investigations of indoor radon measurements in more than 300 rural and urban dwellings in Kosovo and Metohija. All measurements were carried out using CR-39 solid State nuclear track detectors by similar protocols and within two series in 1990-s and in 2000-s, in 34 settlements divided by 9 regions, thus covering significant part of Kosovo. For most of measured points the adjustment for seasonal variation was necessary and had been conducted. Highest average values of indoor radon concentrations were found in rural settlements of Lipljan and Vitina regions, 512 and 452 Bq/m(3), respectively. Combined analysis allows indoor radon concentration of 220 Bq/m(3) to be suggested as representative estimate for Kosovo, while additional data appear. Observed pattern of indoor radon seasonal variation and difference of radon levels between ground and upper floors suggest soil radon as primary source of indoor radon and significance of convection type radon entry. (C) 2010 Elsevier Ltd. All rights reserved

Variance of indoor radon concentration: Major influencing factors

Variance of radon concentration in dwelling atmosphere is analysed with regard to geogenic and anthropogenic influencing factors. Analysis includes review of 81 national and regional indoor radon surveys with varying sampling pattern, sample size and duration of measurements and detailed consideration of two regional surveys (Sverdlovsk oblast, Russia and Niska Banja, Serbia). The analysis of the geometric standard deviation revealed that main factors influencing the dispersion of indoor radon concentration over the territory are as follows: area of territory, sample size, characteristics of measurements technique, the radon geogenic potential, building construction characteristics and living habits. As shown for Sverdlovsk oblast and Niska Banja town the dispersion as quantified by GSD is reduced by restricting to certain levels of control factors. Application of the developed approach to characterization of the world population radon exposure is discussed. (C) 2015 Elsevier B. V. All rights reserved

High variability of indoor radon concentrations in uraniferous bedrock areas in the Balkan region

In this work the strong influence of geological factors on the variability of indoor radon is found in two of three geologically very different regions of South-Eastern Europe. A method to estimate the annual mean concentration when one seasonal measurement is missing is proposed. Large differences of radon concentrations in different rooms of the same house and significant difference in radon concentrations in one season comparing it to the others are noted in certain cases. Geological factors that can lead to such behavior are discussed. (C) 2014 Elsevier Ltd. All rights reserved

Comparison of retrospective and contemporary indoor radon measurements in a high-radon area of Serbia

In Niska Banja, Serbia, which is a high-radon area, a comparison was made between two retrospective radon measuring methods and contemporary radon measurements. The two retrospective methods derive the radon concentrations that occurred in dwellings over longer periods in the past, based on the amount of trapped 2 Po-10 on the surface of glass objects (surface traps, ST) or in the bulk of porous materials (volume traps, VT). Both surface implanted 2 1 Po-210 in glass objects and contemporary radon in air were measured in 46 rooms, distributed in 32 houses of this radon spa-town, using a dual alpha track detector configuration (CR-39 and LR115) and CR-39 track etched detectors, respectively. In addition to the use of surface trap measurements, in 18 rooms (distributed in 15 houses) VT samples of suitable material were also collected, allowing to compare ST and VT retrospective radon concentration estimates. For each room, contemporary annual radon concentrations (CONT) were measured or estimated using seasonal correction factors. The distribution of the radon concentration in all data sets was found to be close to lognormal (Chi-square test GT 0.05). Geometric means (GM) are similar, 3 ranging from 1040 to 1380 Bq m(-3) whereas geometric standard deviations (GSD) for both the retrospective methods are greater than for the CONT method, showing reasonable agreement between VT, ST and CONT measurements. A regression analysis, with respect to the lognormal distribution of each data set, shows that for VT-ST the correlation coefficient r is 0.85, for VT-CONT r is 0. 82 and for ST-CONT r is 0.73. Comparison of retrospective and contemporary radon concentrations with regard to supposed long-term indoor radon changes further supports the principal agreement between the retrospective and conventional methods. (C) 2007 Elsevier B.V. All rights reserved

The concentrations and exposure doses of radon and thoron in residences of the rural areas of Kosovo and Metohija

This paper deals with the results of indoor radon and thoron concentrations and exposure doses obtained for 63 dwellings out of the 14 rural communities of Central Kosovo, North Kosovo and Prizren region. These research activities are part of overall radiological research that has systematically been carried out since 1986, particularly in Kosovo and Metohija regions. Passive radon/thoron discriminative detectors, exposed for three months, were used. The arithmetic mean concentrations of indoor radon and thoron are C(Rn) = 429 Bq m(-3) C(Tn) = 85 Bq m(-3). (C) 2009 Elsevier Ltd. All rights reserved

Collaborative investigations on thoron and radon in some rural communities of Balkans

This paper deals with the results of the first-field use in the Balkans, i.e. Serbia and Republic of Srpska (Bosnia and Hercegovina), of a passive polycarbonate Mark II type and poliallyldiglycol carbonate (Cr-39) alpha track detectors sensitive to thoron as well as to radon. Both types of solid state nuclear track detectors were designed and supplied by National Institute of Radiological Sciences (NIRS), Chiba, Japan. The commercial names for these detectors which all have been field tested in Balkan rural communities are known as: UFO and RADUET passive discriminative radon/thoron detectors. No database of thoron and thoron progeny concentrations in dwellings in Serbia or Balkans region exist, and as a result, the level of exposure of the Serbian population to thoron and its progeny is unknown so far.1st International Workshop on Environmental Thoron and Related Issues, May 19-22, 2010, Chiba, Japa