Search

To control the specific activity of 226Ra in building materials of operated buildings, a non-destructive in situ method consisted in measurements of gamma spectra with a fixed geometry of the detector position in a room is suggested. The calculation of the average specific activity of natural radionuclides in building materials is carried out by comparing the calculated flux density of unscattered gamma quanta normalized to the specific activity of 100 Bq/kg, and the experimentally measured count rates in the photopeak. For the measured values of the average specific activity of 226Ra in building materials, the expected values of radon concentration in rooms were calculated. The developed method has been verified for rooms in modern multi-storey energy-efficient buildings. Concentrations of 232Th and 40K in building materials which contribute to the indoor external radiation exposure can be measured by developed method also.

During last decades, energy saving in new buildings became relevant within the energy efficiency strategies in various countries. Such energy efficient building characteristics as air tightening and low ventilation can compromise indoor air quality, in particular, increase radon concentration. In Russia, a significant part of the new buildings is the energy efficient multi-storey apartment houses. The aim of this study is to assess the significance of possible radon concentration increase in new energy efficient buildings in comparison with typical conventional multi-storey houses of previous periods. Radon surveys were conducted in Russian cities Ekaterinburg, Chelyabinsk, Saint-Petersburg and Krasnodar. The radon measurements were carried out in 478 flats using CR-39 nuclear track detectors. Energy efficiency index (EEI) was assigned to each house. All buildings were divided into six main categories. The smallest average radon concentration was observed in panel and brick houses built according to standard projects of 1970–1990 (four-city average 21 Bq/m3). The highest average radon concentration and EEI were observed in new energy efficient buildings (49 Bq/m3). The trend of radon increase in buildings ranked with high EEI index is observed in all cities. The potential increase of radiation exposure in energy-efficient buildings should be analyzed taking into account the principles of radiological protection.

Study of gross beta activity was conducted in Russian cities Ekaterinburg, Rostov-on-Don, and Nizhny Novgorod. The cities were characterized by continental climate, although they are located in different geographical zones. The bulk urban samples were fractionated with three size fractions: dust (0.002–0.1 mm), fine sand (0.1–1 mm), and coarse sand (> 1 mm). Measurement setup equipped with beta radiometer BDPB-01 was designed to measure the low levels of gross beta-activity in a small amount of the obtained size-fractionated samples. According to the results of the study, the gross beta activity depends on the size fraction and the city. The highest beta activity concentration was found in the dust fraction which is about the same in all cities 0.8–0.9 Bq g−1. In size fractions of fine sand and coarse sand, the beta activity depends on the city. Among other cities, the highest average beta concentration was found in Ekaterinburg (0.8 and 0.6 Bq g−1 in fine and coarse sand fractions, respectively), while the lowest is 0.28 and 0.44 Bq g−1, respectively. The relationship of beta activity concentration with mineral and chemical composition is studied. Average beta activity in the different fractions of the surface–deposited sediment correlates with uranium, thorium, and organic matter concentration. The gross beta activity may be considered an indicator of high contribution of dust and high pollution with Pb, Cu, and Zn in the urban environment.

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.

This paper presents results of an analysis of potentially harmful elements (PHEs, Pb, Zn and Cu) and conservative element (CE, Fe) concentrations in urban surface deposited sediment (USDS). The study was conducted in seven large Russian cities located in different geographic and climatic zones, and in territories with different geology and anthropogenic pressures: Chelyabinsk, Magnitogorsk, Nizhniy Novgorod, Nizhniy Tagil, Rostov-on-Don, Tyumen, and Ufa. The initial geochemical baseline relationships between PHEs and CE concentrations in the USDS were reconstructed for each city applying an approach based on linear weighted fitting of PHE as a function of CE with lower weights assigned to more polluted samples. The reconstructed average initial baseline Pb, Cu, and Zn concentrations varied between 17–52, 25–196, and 91–413 mg kg−1, respectively. Several new criteria for assessing the degree of geochemical transformation and pollution of the urban environment, such as the percentage of polluted samples, average pollutant concentration in polluted samples, and weighting degree index δ, were suggested and compared with common criteria, such as the PHE concentration and the geo-accumulation index. The environmental rank of a city significantly differed depending on whether the criterion for ranking was total PHE pollution or changes in comparison with the initial geochemical baseline. © 2020, The Author(s). Russian Science Foundation, RSF: 18-77-10024 The study was supported by Russian Science Foundation (grant No. 18-77-10024).

In this study, the human health risks of potentially harmful elements (PHEs) in urban surface deposited sediments (USDS) were examined by collecting urban dust samples, measuring their PHE concentrations, and using index evaluation. About 35, 12 and 16 samples are represented a green zones, roads, driveways and sidewalks in residential areas of Ekaterinburg, respectively. The dust fraction (0.002-0.1 mm) was obtained by sieving, filtration, and decantation process. Total concentrations of 10 PHEs were measured using inductively coupled plasma mass spectrometry. The highest concentrations of Pb were found in USDS from green zones, while Fe, V, Mn, Co, Ni, Sn, and Sb on roads, Cu and Zn on driveways and sidewalks. The contamination levels in the investigated land-use areas were studied, where the highest contamination was contributed from Sb in the driveways and sidewalk. Moreover, the pollution in the studied zones was a high load, contributing to anthropogenic activities and traffic emissions. No non-cancerogenic risk was attributed from the PHEs based on the results of health indices (HI 1) for both adult and children, except Co and Ni which has HI 1 for children. The total carcinogenic risk (TLCR) in all urban landscape areas is defined as a high potential inhalation exposure and a low potential ingestion and dermal exposure.

The formation of snow-dirt sludge (SDS) via the mixing of snow and surface-deposited sediment by vehicles and pedestrians is one of the least studied sedimentation processes in urban areas. The aim of this study was to analyse the material, mineral, particle size, and chemical compositions of the SDS solid phase. The study was conducted using Ekaterinburg, Russia, as an example city with an intense anthropogenic impact and a long cold snowy period. The average content of the SDS solid phase was approximately 35 g L−1 of meltwater on heavy traffic roads, of which the dust fraction (−1. On driveways and lawns, the contents of the SDS solid phase were 12 and 6.6 g L−1, respectively. The mineral composition of the SDS solid phase was generally similar to the geology of the surrounding area, which is composed of a mosaicked combination of felsic and mafic complexes. The presence of building material fragments and other anthropogenic particles confirms the significant anthropogenic impact. The chemical composition contained major and minor elements specific to the minerals and materials that constitute the SDS solid phase. There was significant variability in the concentrations of Pb, Cu, and Zn in the granulometric fractions, indicating pollution. Intensive melting of SDS with a high particulate matter (PM) content is an important factor influencing the environmental quality of the urban environment.

The aim of the study is the development of a method of quantitative assessment of the total and size-fractionated amount of urban surface deposited sediment. The method utilises the feature of snow cover to accumulate the surface sediment. Snow-dirt sludge formed as a result of snow, and surface deposited sediment mixing on roads and other urban surfaces accumulates sediment over the winter period. In regions with long winter, the snow-dirt sludge lifecycle presents a delayed runoff event. Testing of the method was conducted in Ekaterinburg, Russia, a city situated in a cold region with long winter. Specimens of snow-dirt sludge and urban surface deposited sediment were collected in winter and summer 2017, respectively. Proportions of concentrations of dust, fine sand and coarse fractions in snow-dirt sludge were compared with the same proportion in surface deposited sediment sampled in the summer season. The average concentration of solid phase material in the snow-dirt sludge was 25 ± 9 g/L of melted water. The dust fraction

Assessment of the annual radon concentration is often required in indoor radon surveys of territories and individual dwellings for comparison with reference levels, studying factors affecting radon accumulation in dwellings, assessment of exposure in epidemiological studies, etc. The indoor radon surveys were carried out in multistorey buildings in eight Russian cities using solid state nuclear track detectors with an exposure period of three months. For these surveys, the estimation of annual indoor radon concentration was required to compare radon levels in buildings of high- and low-energy-efficiency classes located in different cities. To develop approaches to seasonal normalization in high-rise buildings, long-term one-hour radon concentration series obtained applying radon-monitors in 20 flats were analyzed. The dependency of indoor radon concentration on the indoor–outdoor temperature difference was studied taking into account the known natural, technogenic and anthropogenic factors affecting radon levels. The developed model of seasonal variations in multistorey buildings includes winter, summer, and demi-season periods, which differ both in ventilation intensity and dependency of radon concentration on the temperature difference. The developed model allows to estimate annual radon concentration taking into account the actual distribution of outdoor temperatures during the exposure of the track detectors.

In the current paper, the analysis of heavy mineral concentrate (Schlich analysis) was used to study the particles of technogenic origin in the samples of urban surface-deposited sediments (USDS). The USDS samples were collected in the residential areas of 10 Russian cities located in different economic, climatic, and geological zones: Ufa, Perm, Tyumen, Chelyabinsk, Nizhny Tagil, Magnitogorsk, Nizhny Novgorod, Rostov-on-Don, Murmansk, and Ekaterinburg. The number of technogenic particles was determined in the coarse particle size fractions of 0.1–0.25 and 0.25–1 mm. The types of technogenic particle were studied by scanning electron microscopy (SEM) analysis. The amount of technogenic material differed from city to city, the fraction of technogenic particles in the samples varied in the range from 0.01 to 0.43 with an average value of 0.18. The technogenic particles in USDS samples were represented by lithoid and granulated slag, iron and silicate microspheres, fragments of brick, paint, glass, plaster, and other household waste. Various types of technogenic particle differed in morphological characteristics as well as in chemical composition. The novelty and significance of the study comprises the following: it has been shown that technogenic particles are contained in a significant part of the USDS, the quantitative indicators of the accumulation of technogenic particles in the urban landscape have been determined, the contributions of various types of particles to the total amount of technogenic material were estimated for the urban landscape, the trends in the transformation of typomorphic elemental associations in the urban sediments associated with the material of technogenic origin were demonstrated, and the alteration trends in the USDS microelemental content were revealed, taking into account the impurities in the composition of technogenic particles.

Background: Sediment deposition in the urban environment affects aesthetic, economic, and other aspects of city life, and through re-suspension of dust, may pose serious risks to human health. Proper environmental management requires further understanding of natural and anthropogenic factors influencing the sedimentation processes in urbanized catchments. To fill the gaps in the knowledge about the relationship between the urban landscape and sedimentation, field landscape surveys were conducted in the residential areas of the Russian cities of Ekaterinburg, Nizhniy Novgorod, Rostov-on-Don, Tyumen, Chelyabinsk, and Murmansk. Methods: In each city, six elementary urban residential landscapes were chosen in blocks of multi-story apartment buildings typical for Russian cities. The method of landscape survey involved delineating functional segments within the elementary landscapes and describing each segment according to the developed procedure during a field survey. Results: The complexity of sedimentation processes in the urban environment was demonstrated. The following main groups of factors have significant impacts on sediment formation and transport in residential areas in Russian cities: low adaptation of infrastructure to a high density of automobiles, poor municipal services, and bad urban environmental management in the course of construction and earthworks. Conclusion: A high sediment formation potential was found for a considerable portion of residential areas.

Detailed analysis of indoor radon concentration distribution by floors was conducted in four children institutions, one office building and two residential houses in Russian cities to develop approaches to draw up a program of radon survey for big buildings. Higher variability of radon concentration was found in high geogenic radon potential (GRP) area when the soil is the main source of radon. No essential dependence of radon concentration on the floor in high-rise buildings was found in low GRP area. The number of required radon measurements is estimated using obtained characteristics of radon variability.

Influence of living habits and meteorological parameters on indoor radon concentration in a new energy efficiency multi-storey flat building typical for Russian cities was studied using radon time series analysis. Continuous indoor radon measurements were conducted in four flats of the same multi-storey residential building in Ekaterinburg, Russia. Factors influencing indoor radon in surveyed building (by rank) are as follows: ventilation regime> indoor/outdoor temperature difference > wind direction. Intentional ventilation frequency, temperature difference and wind direction explain together up to 46% of indoor radon variability in a flat of multi-storey building.

Long-term radon time series were analyzed in 14 rooms and offices to search factors influencing indoor radon concentration in high-rise buildings. Radon entry to living rooms is determined both by diffusion from building materials and advection from adjoined low-ventilated spaces. Humans affect on seasonal and diurnal radon concentration changes in high-rise buildings by activating ventilation system. Indoor-outdoor temperature difference significantly influence on the air exchange rate under uncontrolled ventilation, which is especially important in new energy efficient buildings.

Indoor exposure to natural radon is a factor that influences lung cancer risk worldwide. The present study includes a meta-analysis of epidemiological data on the relationship between lung cancer and indoor radon. Altogether, 31 case–control studies with 20,703 cases, 34,518 controls and 140 individual odds ratio (OR) estimates are included in the meta-analysis. Weighted median OR was calculated for five radon intervals. The following parameters were used for the weighting: standard error of OR, duration of radon concentration measurement, and relative number of controls in reference intervals. The dependence of the weighted median OR on the radon concentration was estimated applying linear non-threshold and threshold models. The results obtained suggest a significant linear no-threshold exposure–effect relationship for radon concentrations above 100 Bq/m3, with a slope of 0.14 (95% confidence interval 0.08–0.21) per 100 Bq/m3.

Radon daughters in the atmosphere of dwellings, public buildings, and workplaces cause lung cancer. Radiation safety in a situation of indoor radon exposure is ensured by means of controlling natural radioactivity during the buildings construction and maintenance. In recent decades the energy saving has resulted in increase of radon concentration in new buildings comparing to conventional buildings. High-rise buildings where building materials are the main source of radon entry are of particular interest due to considerable influence of ventilation on the radon dynamic. To justify and optimize protection of the population against radon exposure in new energy-efficient multi-apartment buildings, a comprehensive understanding of the processes of radon transport and accumulation is required. Developed dynamic model of radon entry and accumulation in an energy-efficient multi-apartment building consists of building and room model, radon source model, ventilation model, and mass transport model. The dynamic model takes into account the basic physical properties of radon transport – diffusion and advection. Data of model experiments and observations of the radon accumulation in the real dwellings were considered to choose appropriate values of the model. Basing on simulation results, the possible range of radon concentrations under the expected concentrations of 226Ra in building materials was estimated. Simulation of indoor radon behavior approved that increased indoor radon exposure in multi-storey energy-efficient buildings can arise due to low active ventilation frequency and high 226Ra concentration.

The objective of the study was comparison of the doses received due to contamination of the Techa River with those received from the indoor radon exposure. The study was performed on the example of Muslyumovo, the village closest to Mayak nuclear complex. The accidental doses were estimated using data on radionuclide intakes and ICRP-72 dose coefficients, and Techa River Dosimetry System. Radon exposure was estimated applying results of the radon surveys in 1992 and 2015. The doses prevented by means of different protection measures were considered. The maximum reduction of population exposure could be achieved in the case of timely evacuation to uncontaminated territory together with the indoor radon prevention measures.

The radon survey of kindergartens has been conducted in Sverdlovskaya oblast during 2013-16. Indoor radon concentrations have been measured in 180 kindergartens in 21 villages and 10 towns. The LR-115 nuclear track detectors were placed in 560 rooms (three or four rooms per kindergarten) during 2-3 months. To obtain annual values, radon measurements were carried in the cold and warm seasons. The arithmetic and geometric means of annual indoor radon concentrations in rooms are 59 and 42 Bq/m3 respectively, GSD = 2.33. Analysis of the building factors affecting radon entry is presented. The detailed radon survey was performed in one kindergarten where exceeding of national action radon level was observed.

Obtaining of the representative sample of dwellings is a basic requirement to organization of the radon survey. Since random selection is often impossible, quasi-random approaches are used. The aim of the study is to analyze errors in radon exposure assessment that resulted from rejecting the random selection. Both the modeling and experiments were conducted. Three types of errors were observed: shifting of the mean, change of the variance and mixture of the previous two.

The inhalation exposure to dust in the urban environment for adult and child is very important due to health issues. The radionuclides Ra-226 and Th-232 were measured in the samples of urban surface deposited sediments. The average concentrations of Ra-226 and Th-232 in dust are 20.8 and 15.3 Bq kg-1, respectively. The effective dose is estimated depending on the daily activity and air dust concentration for the adult and child. The results show that the total effective dose received during 70 years by adult without outdoor activity is 0.74 µSv under exposure to air dust concentration 1x10-4 g/m3, which is typical for the city of Ekaterinburg. Critical scenario of exposure of an adult person to radioactive material in particulate matter in the air including such daily activities as training, bicycle driving and work in urban environment results in the total effective dose 17.8 µSv during 70 years at air dust concentration equal to the diurnal Maximum Permissible Limit (1.5x10-4 g/m3). Also, the critical children group can be exposed to radionuclides by inhalation through daily outdoor games, sport activity, training, bicycle etc (8 hours daily during vacation, 4 hours daily during school time, 2000 hours per year from 7 years to 17 years). The total effective dose for critical children group is 2.9 µSv. Thus, the effective doses due to inhalation of natural radioactivity in the dust in city of Ekaterinburg are relatively low in comparison ICRP reference level.

The objective of the study was to characterize morphology and chemical composition of anthropogenic particles in contemporary sediments in an urban environment. The object of the study was the contemporary surface dirt and dust sediments. The study was conducted through the example of Ekaterinburg (Russia). Six typical neighborhoods were chosen for investigations within the residential area of the city. The samples of environmental compartments were collected on these territories. Samples of dirty snow sludge in the winter season, and samples of soil, ground, surface dirt and dust sediment in the summer season were collected in courtyards and adjacent areas of each neighborhood. The anthropogenic particles were selected by visual inspection from the 0.25–1 mm particle-size fraction of the collected environmental compartments. Morphological analysis was conducted by optical microscopy. The chemical composition and structure of particles were determined by scanning electron microscopy. According to their morphological features, structure and elemental content, the analyzed particles were divided into seven different groups: brick, glass, spherical particles, foil, tire fragments, slag and building plaster. The catalog of the particles was compiled.

The main contribution to population exposure is due to radon and thoron progenies and not radon itself. The aim of this study was therefore to estimate annual effective dose using the results of Direct Radon and Thoron Progeny Sensors were exposed in 69 selected schools and 319 dwellings in several regions of Balkans: in Serbia: regions of Sokobanja and Kosovo and Metohija, Republic of Macedonia, Republic of Srpska and Slovenia. Obtained average total effective doses are in the range from 0.22 mSv a-1 (schools in Republic of Srpska) to 2.5 mSv a-1 (dwellings in Kosovo) and are below the reference level of 10 mSv a-1 recommended by International Commission on Radiological Protection. © The Author(s) 2019. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

The aim of the study: to analyze the risk of lung cancer caused by exposure to indoor radon using an environmental study, taking into account recent data on the possible effect of Human Papillomavirus, based on lung cancer mortality and radon exposure in the Russian regions. Materials and methods: in the analysis, linear dependencies of lung cancer against influencing factors were used. The average radon concentration for the regions of Russia was earlier reconstructed on the basis of the annual reports of the form 4-DOZ. Information on morbidity and mortality from malignant neoplasms in Russia was obtained from annual reports issued by the Р. Hertsen Moscow Oncology Research Institute. As a surrogate of the level of infection with Human Papillomavirus, the incidence of cervix cancer was used. The smoking prevalence was estimated applying data on the incidence of tongue cancer. Results: taking into account smoking and infection with Human Papillomavirus, it is possible to obtain estimates of lung cancer excess relative risk when induced by radon in dwellings consistent with the results of case-control studies. Conclusion: the analysis of regionally aggregated data on deaths from lung cancer in Russia, the average level of indoor radon concentrations and significant risk factors for lung cancer confirms the linear threshold-free concept of radiation-induced carcinogenesis.

Indoor radon concentration was studied in the 14 settlements located near the Techa River, which was contaminated by radioactive wastes in 1950-s. Results of the radon survey were used for analysis of the relationship between the indoor radon and main geologic factors (Pre-Jurassic formations, Quaternary sediments and faults), local geogenic radon potential and anthropogenic factors. Main influencing factors explain 58% of the standard deviation of indoor radon concentration. Association of the air exchange influence over radon concentration with underlying geological media was related to different contributions of geogenic advective and diffusive radon entries. The properties of geological formation to transfer radon gas in interaction with the house can be considered within the radon geogenic potential concept. The study of the radon exposure of the Techa River population can be used to estimate the contribution of natural radon to the overall radiation exposure of the local population during the period of radioactive waste discharges.

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.

Surface runoff represents one of the major mechanism connecting sources, transport, deposition and storage of the particle matter in urban sediment cascade. The urban surface deposited sediment represents a medium for the transport and nonpoint source of pollution in cities. The study is aimed to characterize the role of surface stormwater runoff in accumulation of the contemporary surface deposited sediments in the urban environment taking to account the seasonal factor. The study was conducted on the example of residential area of Ekaterinburg, Russia. The role of the surface stormwater runoff in the formation of the urban surface deposited sediments was discussed. The snow and dirt mixture accumulates surface runoff and pollutants in it during the winter season in an urban area. A large supply of water accumulated in the snow cover during the cold period contributes to the formation of large volumes of snow-mud mixture during spring. The active snowmelt in the spring leads to the formation of snow-dirt sludge and transfer of the sedimentary material.

The contemporary sedimentation processes participate in the formation of fluxes of the solid substances in an urban area, forming together a source of pollution, transit and depositing media. The patterns of forming the urban surface deposited sediments were determined on the example of Russian metropolis Nizhny Novgorod. Two schemes of the research were implemented in residential districts of the city in the summer field season 2018. The first research design scheme represented a detailed survey of residential quarters of the city. It included a collection of 25 samples of environmental compartments from five residential quarters with multi-storey buildings. The sampling was conducted in various functional landscape parts at the courtyard and facade areas. Each sample was separated into particle size fractions. Chemical and mineral analysis was performed in each granulometric subsample of the collected samples. The second scheme represented the urban geochemical study based on sampling the sediments from local surface depressed zones of microrelief in the city. The 40 samples were collected at the territory of the city on an irregular grid. The sampling was carried out in residential areas in blocks with multi-storey buildings. One sample represented a combined sample of sediments from local surface zones of microrelief by 3-5 localizations from the area of the block. Chemical analysis of the collected samples was conducted. The maximum content of dust (0.002-0.01 mm) 39% was found in soil, while the lower mean dust content was found in the samples of sediment from local surface depressed zones of microrelief (30 %) and in the road deposited sediments (30 %). The mineral composition of soil and sediment in Nizhny Novgorod is represented by quartz sand (approx. 55 %). In the samples of sediments, the minerals' content is basically characteristic for acid and metasomatic rocks. Building materials' content in the sediments reaches up to 20%. The maximum organic matter content was found in fine dust fraction 2-10 microns 21% in soils and 5% on the roads. Differentiation of the mineral content in the samples is observed for the various particle size fractions and different functional parts of the quarters. The highest content of metals of anthropogenic association (such as Pb, Zn and Cu) was found in the dust fraction. The Pb and Zn concentrations in samples of sediment of depressed areas of microrelief and road dust were significantly lower than in the soil. © Published under licence by IOP Publishing Ltd. Russian Science Foundation, RSF: 18-77-10024 The study was supported by Russian Science Foundation (grant No. 18-77-10024).

Cohen's ecological analyses revealed negative correlation between the lung cancer mortality and average indoor radon concentration in the US counties, that contradicts to linear non-threshold (LNT) model and is inconsistent with results of case-control studies. The aim of this study was to analyze dependence between radon exposure and lung cancer mortality rate taking into account more complete data on smoking and new findings on association of the lung cancer with human papillomavirus (HPV) infection.Information on the cancer rates in the US counties and Russian oblasts, smoking prevalence and indoor radon concentration was found in literature. The cervix cancer incidence rate was used as surrogate of the HPV infection prevalence. The analysis included calculation of the coefficients of linear dependence between radon exposure and lung cancer mortality rate with adjustment to smoking and HPV infection prevalence.After adjustment for the most relevant data on smoking and HPV infection, correlation between the lung cancer mortality and indoor radon was found to be consistent with results of the case control studies.Analysis of geographically aggregated data on the lung cancer mortality and radon concentration in dwellings with adjustment to the significant risk factors confirms both the linear non-threshold dependency and results obtained in studies with individual accounting for the smoking and radon.

The study provides data on contemporary levels of radiation exposure of organs and tissues of murine rodents (several species of mice and voles) inhabiting the East-Ural Radioactive Trace. The estimation procedure involves the most advanced approach based on application of appropriate voxel phantom and biokinetic model. Input data for dose assessment are the results of measurements of skeletal 90Sr activity concentration. Maximal internal dose to skeleton, accumulated during 45 days, is 303 mGy. Median internal dose rates on the last day before trapping were 0.83, 0.092 and 0.023 mGy/day for animals trapped at the sites with initial (1957) 90Sr surface contamination >37 MBq/m2, 18.5–37 MBq/m2 and 0.074–18.5 MBq/m2 respectively. Taking to account internal and external exposures, upper boundary of the ICRP Derived Consideration Reference Level (DCRL) is exceeded on the territory with maximal level of the initial 90Sr surface contamination. On the territory with 18.5–37 MBq/m2, whole body mean dose rates to murine rodents exceed the lower boundary of DCRL. On the areas with lower level of surface contamination, even the 90-th percentile of dose rate is below the DCRL.

The accumulation of the contemporary surface dirt and dust sediments is an important problem of an urban area. The surface dirt sediment is deposited on the various surfaces both inside and outside the residential blocks. The sediment represents the secondary and nonpoint pollution source due to the presence of the environmental toxicants, heavy metals and pathogens in their content. The aim of the study was to determine the mineral phase composition of surface sediment in the city of Ekaterinburg in order to identify the sources of its origin. The 60 samples of surface sediment were collected in summer at the different parts of residential blocks (traffic ways, sidewalks and lawns, inner yard area, parking lots, and green areas). The sediment samples were fractionated by the particle size fractions: 0.002-0.01 mm, 0.01-0.05 mm, 0.05-0.1 mm, 0.1-0.25 mm, 0.25-1 mm and >1 mm. The particle size fractions were analysed by X-ray diffraction. According to the results of analysis the investigated mineral composition of the surface sediments represent the complex multi-phase mixtures, similar in mineral composition (quartz, microcline, plagioclase, magnetite, chlorite etc.). The sources of the mineral component in the surface sediment were identified.

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.

The aim of the paper is a reconstruction of the national distribution and estimation of the arithmetic average indoor radon concentration in Russia using the data of official annual 4-DOZ reports. Annual 4-DOZ reports summarize results of radiation measurements in 83 regions of Russian Federation. Information on more than 400,000 indoor radon measurements includes the average indoor radon isotopes equilibrium equivalent concentration (EEC) and number of measurements by regions and by three main types of houses: wooden, one-storey non-wooden, and multi-storey non-wooden houses. To reconstruct the national distribution, all-Russian model sample was generated by integration of sub-samples created using the results of each annual regional program of indoor radon measurements in each type of buildings. According to indoor radon concentration distribution reconstruction, all-Russian average indoor radon concentration is 48 Bq/m(3). Average indoor radon concentration by region ranges from 12 to 207 Bq/m(3). The 95-th percentile of the distribution is reached at indoor radon concentration 160 Bq/m(3).

The contemporary radiation doses to the organs and tissues of murine rodents inhabiting the most contaminated part of the EURT were estimated. The bones of animals trapped in 2005 at territories with a surface (90)Sr contamination of 24-40 MBq/m(2) were used for dose reconstruction. The concentration of (90)Sr in the animals' skulls was measured using the nondestructive method of bone radiometry. The dose estimation procedure included application of the published values of absorbed fractions of beta-radiation energy for different combinations of source and target organs, accounting for the distribution of radionuclide by organs and tissues. Twelve conversion coefficients were obtained to link the skeleton (90)Sr concentration and doses to eleven organs and the whole body. The whole-body dose rate on the 45th day after the beginning of exposure normalised to whole-body activity is 0.015 (mGy day(-1))/(Bq g(-1)). The estimation yields the following values of doses for Microtus agrestis, Sylvaemus uralensis and Clethrionomys rutilus, respectively: maximum absorbed doses in the skeleton: 267, 121 and 160 mGy; mean whole body internal doses: 37, 14 and 23 mGy; mean internal dose rates on the last day before trapping: 1.2; 0.44 and 0.75 mGy/day. Approaches to the assessment of doses to foetuses and to offspring before weaning were also developed.