Investigation on awareness of radon and health risks in non-uranium miners from 2020 to 2021 / 中华放射医学与防护杂志

Objective:To understand the non-uranium miners′ awareness of radon and health risks in China and analyze the relevant influencing factors, in order to provide research basis for radiological protection institutions and employers to carry out radon health education.Methods:Male miners in 32 typical non-uranium mines from 11 provinces were selected by using cluster random sampling method from June 2020 to December 2021. The awareness of radon and health risks was investigated, and the influencing factors were analyzed by binary logistic regression model.Results:A total of 1 184 non-uranium miners were investigated, and the radon awareness rate of them was 19.17%. 36.56% of the non-uranium miners heard about radon knew the radon health risks accurately, and 18.06% could identify the measures to reduce radon concentration correctly. Univariate analysis showed that the radon awareness rate of non-uranium miners varied with different education levels, labor relations, post categories, and regions ( χ2=55.92, 21.89, 64.31, 11.26, P<0.05 ). The result of logistic regression analysis showed that a bachelor degree or above, regular employee, administrative personnel and technical personnel were influencing factors of the radon awareness level ( χ2=12.81, 6.58, 5.66, 21.44, P<0.05 ). There was no statistically significant difference of radon awareness rate in different ages, working years, regions, and smoke groups ( P>0.05 ). Conclusions:The awareness level of radon and health risks of non-uranium miners was relatively low in China. Radiological protection institutions and employers should strengthen education and training of radon related knowledge in non-uranium miners through mass media, on-duty training, contract notification and workplace publicity board notification, so as to improve their personal protection consciousness.

Investigation and analysis of indoor radon concentration of urban residents in Shiyan, China / 中国辐射卫生

@#<b>Objective</b> To monitor the indoor radon concentration of urban residents in Shiyan, China, and to analyze the related influencing factors. <b>Methods</b> From April to July, 2019, RSKS standard detectors were used to measure the indoor radon concentration of 125 households in Shiyan, and the results were analyzed. <b>Results</b> The indoor radon concentration of residents in Shiyan showed a skewed distribution, ranging from 13.8 to 145 Bq/m³, and <i>M</i> (<i>P</i>₂₅,<i>P</i>₇₅) was 38.3 (29.0,62.0) Bq/m³. The estimated annual effective dose of radon and radon daughters from inhalation was 0.52-5.50 mSv, and <i>M</i> (<i>P</i>₂₅,<i>P</i>₇₅) was 1.45 (1.10, 2.36) mSv, which was consistent with literature. Building structure (<i>H</i> = 14.10, <i>P</i> < 0.001), floor (<i>H</i> = 24.41, <i>P</i> < 0.001), and geographical region (<i>H</i> = 8.963, <i>P</i> < 0.05) were influencing factors of indoor radon concentration, and the differences were significant. <b>Conclusion</b> The indoor radon concentration of urban residents in Shiyan is lower than the national standard limit. However, in daily life, it is still necessary to take appropriate measures to reduce the concentration of indoor radon as much as possible.

Investigation of radioactivity level in an open-pit coal mine in Xinjiang, China and evaluation of personnel exposure dose / 中国辐射卫生

@#<b>Objective</b> To investigate and analyze the levels of γ dose rate and radon concentration at all sites in a large open-pit coal mine with radioactivity that had been mined for many years in Xinjiang, China, and to estimate the effective dose exposed to the personnel. <b>Methods</b> A portable γ dose-rate instrument FH40G was used for fixed-point monitoring of the mining area, and a continuous radon detector was used for 24 h continuous monitoring of radon concentration level in the site. The personnel exposure dose was estimated according to the measured γ dose rate and radon concentration. <b>Results</b> In this open-pit coal mine, the range of γ dose rate was 51.4-435.8 nGy/h; the mean 24 h radon concentration was 15-25 Bq/m³; the range of annual effective dose to the personnel was 0.29-1.29 mSv/a. <b>Conclusion</b> According to the results of the survey, radon concentration levels at all sites are low, and no remedial action is required. The personnel exposure dose at most of the sites is far below the standard requirements, and some protective measures need to be taken in some areas of the dump.

Indoor radon concentration and its changing trend in northeastern China / 中国辐射卫生

@#<b>Objective</b> To investigate the indoor radon concentration and its changing trend in northeastern China. <b>Methods</b> We measured indoor radon levels cumulatively for over three months by solid state nuclear track detection in a total of 261 houses in multi-story or high-rise buildings in Shenyang, Changchun, Harbin, Heihe, and Yichun in northeastern China. The measurement lasted one year in Changchun for seasonal changes. <b>Results</b> The average indoor radon concentration in the five cities was 88 Bq/m³, ranging from 12 to 558 Bq/m³. The indoor radon concentrations were ≤ 100 Bq/m³ in 75.1% of the houses, and ≤ 300 Bq/m³ in 97.7% of the houses. The indoor radon concentration increased with the age of buildings. The indoor radon concentration was highest in winter, and it was higher in summer than in autumn and spring. <b>Conclusion</b> The indoor radon concentration in northeastern China increased compared with the data of 1980s and 1990s. It is highest in the winter heating season, and higher in summer than in spring and autumn. Indoor radon exposure deserves attention.

Preliminary estimation of lung cancer risk of radon exposure in a uranium mine using different corrections / 中国职业医学

Objective: To explore the correction factors of lung cancer caused by radon exposure in a uranium mine, and estimate the excess relative risk (ERR) coefficient of lung cancer caused by radon in the uranium miners. Methods: Male miners who worked in a uranium mine more than one year in Hunan Province from 1958 to 2018 were selected. This study preliminarily estimated the ERR coefficient of lung cancer caused by radon in the miners with different corrections using the Possion regression model. Results: This study cohort included 4 851 uranium miners, with 187 miners died with lung cancer from 1958 to 2018, and cumulative follow-up of 207 251 person-year. The ERR coefficient of lung cancer caused by radon without correction factors was estimated to be 0.21%/WLM (95%CI: 0.04%/WLM-0.27%/WLM). In the final model, the exponential correction factors of radon-induced lung cancer were time since exposure and exposure rate. In this model, if time since exposure was 45 years and the average exposure rate was 0.14 WL, the estimated ERR coefficient was 1.73%/WLM (95%CI: 0.36%/WLM-3.11%/WLM). The ERR decreases by about 60.00% for every 10 years since exposure, and increases by about 30.00% for every one WL increase exposure rate. Conclusion: The correction factors of lung cancer caused by radon in uranium miners in this mine were the time since exposure and exposure rate. It was preliminarily estimated that the ERR coefficient of lung cancer caused by radon in the occupational radon exposed population in this uranium mine was 1.73%/WLM (95%CI: 0.36%/WLM-3.11%/WLM).

An investigation of indoor radon concentrations and estimation of public exposure doses in Yinchuan, China / 中国辐射卫生

Objective To primarily investigate the indoor radon concentrations in the urban and rural dwellings in Yinchuan, China, and to estimate the effective dose. Methods A total of 67 dwellings, which included 49 urban households and 18 rural households in Yinchuan, were selected to cumulatively measure the indoor radon concentrations for more than 3 months using solid state nuclear track detection. Results The arithmetic mean, geometric mean, median, and range of indoor radon concentrations in urban and rural areas in Yinchuan were 64 Bq/m3, 59 Bq/m3, 57 Bq/m3, and 25-172 Bq/m3, respectively. Surveillance sites with an indoor radon concentration higher than 100 Bq/m3 accounted for 7.5%. Indoor radon concentrations in rural areas were higher than those in urban areas. Indoor radon concentrations were highest in winter and lowest in summer. The effective dose of indoor radon exposure among residents in Yinchuan was 1.86 mSv/a. Conclusion The results of indoor radon concentrations measured in this investigation in Yinchuan are significantly higher than those measured in the 1990s. The annual effective dose is higher than the mean levels in the world and China.

Radon exposure: a major cause of lung cancer in nonsmokers / Exposição ao radônio: uma importante causa de câncer de pulmão em não fumantes

ABSTRACT Exposure to radon can impact human health. This is a nonsystematic review of articles written in English, Spanish, French, or Portuguese published in the last decade (2013-2023), using databases such as PubMed, Google Scholar, EMBASE, and SciELO. Search terms selected were radon, human health, respiratory diseases, children, and adults. After analyzing the titles and abstracts, the researchers initially identified 47 studies, which were subsequently reduced to 40 after excluding reviews, dissertations, theses, and case-control studies. The studies have shown that enclosed environments such as residences and workplaces have higher levels of radon than those outdoors. Moreover, radon is one of the leading causes of lung cancer, especially in nonsmokers. An association between exposure to radon and development of other lung diseases, such as asthma and COPD, was also observed. It is crucial to increase public awareness and implement governmental control measures to reduce radon exposure. It is essential to quantify radon levels in all types of buildings and train professionals to conduct such measurements according to proven efficacy standards. Health care professionals should also be informed about this threat and receive adequate training to deal with the effects of radon on human health.

RESUMO A exposição ao radônio pode ter impacto na saúde humana. Esta é uma revisão não sistemática de artigos escritos em inglês, espanhol, francês ou português publicados na última década (2013-2023), utilizando bancos de dados como PubMed, Google Acadêmico, EMBASE e SciELO. Os termos de busca selecionados foram radônio, saúde humana, doenças respiratórias, crianças e adultos. Após a análise dos títulos e resumos, os pesquisadores inicialmente identificaram 47 estudos, que foram posteriormente reduzidos para 40 após a exclusão de revisões, dissertações, teses e estudos de caso-controle. Os estudos mostraram que ambientes fechados como residências e locais de trabalho apresentam maiores níveis de radônio do que ambientes externos. Além disso, o radônio é uma das principais causas de câncer de pulmão, especialmente em não fumates. Também foi observada associação entre exposição ao radônio e desenvolvimento de outras doenças pulmonares, como asma e DPOC. É crucial aumentar a conscientização do público e implementar medidas governamentais de controle para reduzir a exposição ao radônio. É fundamental quantificar os níveis de radônio em todos os tipos de edifícios e treinar profissionais para realizar essas medições segundo padrões de eficácia comprovada. Os profissionais de saúde também devem ser informados sobre essa ameaça e receber formação adequada para lidar com os efeitos do radônio na saúde humana.

Investigation on radon exposure level in 38 districts and counties in Chongqing / 中国热带医学

@#Abstract: Objective　In order to understand the radon exposure level of homes in Chongqing, this survey was carried out on the indoor radon concentration in 38 districts and counties of Chongqing. Methods　According to the population ratio of every 100 000 people, one monitoring site was arranged, and the number of parallel samples was 10% of the distribution sites. The monitoring sites covered 38 districts and counties in Chongqing. A total of 1 019 residential monitoring sites in 38 districts and counties in Chongqing were measured with radon accumulation detectors from July 2020 to June 2021. Results　The five districts/counties in Chongqing having the highest average concentration of residential radon in the year were Xiushan County 78.8 Bq/m3, Qianjiang District 78.0 Bq/m3, Yubei District 73.9 Bq/m3, Youyang County 71.4 Bq/m3 and Shapingba District 69.8 Bq/m3. The five districts/counties with the lowest mean concentration of indoor radon were 37.6 Bq/m3 in Zhongxian County, 36.4 Bq/m3 in Changshou District, 33.7 Bq/m3 in Kaizhou District, 33.2 Bq/m3 in Liangping District and 27.3 Bq/m3 in Wushan County. The concentration levels of radon in four seasons were 46.0 Bq/m3, 53.4 Bq/m3, 45.1 Bq/m3 and 59.5 Bq/m3, respectively. The concentration of radon was higher in Summer and Winter, and lower in Spring and Autumn, and the difference of concentration among four seasons was statistically significant (P<0.001). The radon concentration of newly built buildings after 2017 was relatively high, up to 61.8 Bq /m3, but there was no statistical significance in radon concentration in different building ages (P>0.05). The concentration of radon in rooms of buildings with less than 10 floors was higher, up to 63.2 Bq /m3, and there were significant differences in radon concentration among rooms of different floors (P<0.05). The average annual radon concentration in houses in Chongqing was about (51.6±19.5) Bq/m3, and the average annual effective dose of inhaling radon and its progeny by house-related people was about (1.38±0.52) mSv. Conclusion　The average annual radon concentration level of houses in Chongqing is within the standard limit value recommended by China, but the prevention and control of radon should be strengthened.

Application and analysis of radon-reduction methods in indoor radon pollution control / 中国辐射卫生

@#<b>Objective</b> To investigate the suitable methods for reducing the concentration levels of residential radon and its daughters. <b>Methods</b> Three rooms were selected and treated by natural ventilation, air purifier, and sealing/shielding, respectively. The EQF3120 device was used to measure the concentrations of radon and its daughters, and the alpha nuclear trail detector was used to measure indoor radon concentration. The three methods were compared in terms of radon reduction effect. <b>Results</b> After natural ventilation for 2-10 hours, the average reduction rates of the concentrations of radon and attached and unattached radon daughters in the room were 87.7%, 89.8%, and 93.7%, respectively; in the room with air purifier, the concentrations of radon and attached and unattached radon daughters were reduced by 46.3%, 94.5%, and 45.3%, respectively; after sealing and shielding, the concentration of radon was reduced by 74.9% after 1 month and 59.2% after 1 year. <b>Conclusion</b> All three methods have a marked effectin reducing the concentrations of indoor radon and its daughters, and natural ventilation is the most economical and effective method for reducing radon.

Current health status of high-radon exposure miners in a typical non-uranium mine in Jiangxi Province, China / 中国辐射卫生

Objective To investigate the health status of high-radon exposure miners in a typical non-uranium mine in Jiangxi Province, China. Methods A general survey was conducted to investigate the basic situation and awareness rate of radon among underground miners aged ≥ 40 years, and the occupational health examination and low-dose lung computed tomography scan were carried out. Results The awareness rate of radon among miners working down the mine was only 3.70%. The peripheral blood lymphocyte chromosome aberration analysis showed an aberration rate of 0% per 100 cells. The peripheral blood lymphocyte micronucleus test showed an abnormal rate of 0.02‰. Ophthalmic examinations (slit-lamp examination of the lens, the vitreous body, the fundus) showed no abnormality. The abnormal rate of leukocyte count was 3.70%, and the detection rate of small lung nodules was 48.15%. Conclusion The high-radon exposure minors had a high detection rate of small lung nodules, and lack knowledge of radon. It is urgent to strengthen the publicity and education on the hazards of radon and the prevention and control of occupational diseases.

Risk assessment models of radon-induced lung cancer and their preliminary application / 中华放射医学与防护杂志

Radon is the second largest environmental factor inducing lung cancer after smoking. In recent years, with the deeper epidemiological investigation on radon and lung cancer and the further improvement of its methodology, new progress has been made in the research on risk assessment models. This paper reviews the relative risk models of radon-induced lung cancer developed by several international academic organizations or research teams, and briefly introduces the background information on the models and the main factors considered. Based on the indoor radon concentrations in different decades in China, the relative risks of radon-induced lung cancer were estimated and analyzed, together with some suggestions given for more accurate evaluation of lung cancer induced by indoor radon in the future.

Risk estimation for lung cancer caused by indoor radon exposure in China based on EPA/BEIR-VI model / 中华放射医学与防护杂志

Objective:To estimate the attribution share of residents′lung cancer caused by indoor Radon.Methods:Based on the 2015 lung cancer mortality, all-cause mortality from China together with nationally representative smoking rate and the average indoor radon concentration of 30 Bq/m 3, the relatively authoritative and applicable EPA/BEIR-VI risk model was used to predict the lung cancer mortality caused by indoor radon exposure. Results:The excess relative risk (ERR) of indoor radon-related lung cancer mortality among the male non-smokers is higher than that of smokers. For the age-group above 50, the male smokers and male non-smokers have the highest ERR values, which were 0.511 and 0.230, respectively. Assuming the exposure incurred starting at age 0 with the same radon concentration, the lifetime risk of men and women non-smokers is higher than that of the smokers of the same gender. The higher the radon concentration, the higher the lifetime risk of lung cancer. Assuming that the radon concentration level in China is 30 Bq/m 3, the number of deaths from indoor radon-related lung cancer in 2015 is about 55 512. According to this, about 6.62% of lung cancers are caused by indoor radon exposure. If we assume that radon concentration levels are 40 Bq/m 3and 70 Bq/m 3 in China, approximately 8.82% and 15.38% of lung cancer deaths can be attributed to indoor radon exposure. Conclusions:Indoor radon exposure is an important environmental factor that causes Chinese residential lung cancer. Effective measures should be taken to prevent and control the increasing indoor radon levels. In order to accurately assess risk of lung cancer morality caused by indoor radon, more detailed data such as the indoor radon level in China are needed.

MiRNA expressions in peripheral blood plasma of workers in a certain mine / 中华放射医学与防护杂志

Objective:To investigate the effect of radon on the expressions of miR-16, miR-106b, miR-449a, let-7g, miR-21, miR-221 and miR-34a in peripheral blood plasma of miners.Methods:A total of 46 randomly selected miners worked underground(the underground group)and 38 miners worked aboveground (the control group). MiRNA levels in the underground and control groups were detected by qRT-PCR and their relationship with cumulative effective dose was further analyzed.Results:The levels of miR-106b, miR-21, miR-221 in plasma of the study group were significantly higher than those in the control group( Z=-2.32, -2.47, -2.79, P<0.05), the corresponding Fc values were 1.61, 1.75, 1.30, respectively. The levels of miR-16, miR-449a, let-7g and miR-34a were slightly higher than those in the control group ( P>0.05). After controlling of confounding factors such as age, BMI and smoking, the alteration of miR-16, miR-106b, let-7g, miR-21 and miR-221 in plasma of the underground group were positively correlated with the cumulative effective dose( t=2.50, 3.31, 2.60, 2.95, 3.25, P<0.05). No significant difference was observed in the plasma levels of miR-449a and miR-34a between the two groups ( P>0.05). Conclusions:miR-106b, miR-21 and miR-221 could be used as potential biomarkers of radon exposure.

Effects of radon exposure on lung function and metal balance in mice / 中华放射医学与防护杂志

Objective:To explore the disturbance of metal element balance in mice after exposure to radon.Methods:Mice were randomly divided into control group, radon exposure of 30 WLM group, 60 WLM group and 120 WLM groups, with 10 mice in each group. After radon exposure with the cumulative dose, the lung function of mice was detected by a non-invasive pulmonary function testing instrument. Mice blood was taken from eyeballs. The lungs, heart, liver, kidney and spleen were also collected. HE staining was used to observe the pathological changes of lung tissue. Inductively coupled plasma mass spectrometry (ICP-MS) was used to detect the content of metal elements, including essential trace elements in the body: chromium (Cr), molybdenum (Mo), cobalt (Co), selenium (Se), copper (Cu), zinc (Zn), manganese (Mn), nickel (Ni), and potentially toxic elements: arsenic (As), tin (Sn), lead (Pb), aluminum (Al), mercury (Hg), cadmium (Cd), and silver (Ag).Results:Compared with the control group, lung ventilation function of the radon-exposed mice was decreased, alveolar structure was destroyed, and the contents of pulmonary metal elements Cr, Al, Pb, Sn( F=0.34, 0.66, 3.14, 1.16, P<0.05) and essential trace elements Mn, Cr, Zn, and Mo in the blood were decreased( F=0.65, 1.44, 0.97, 2.08, P<0.05), while the elements of Cu, Mo, Se and As in the lungs were increased( F=1.31, 1.26, 0.81, 2.04, P<0.05), and the element contents in other tissues also fluctuated. Conclusions:Inhalation of a certain cumulative dose of radon can reduce the lung ventilation function of mice and induce lung inflammation, as well reduce the content of essential trace elements in the lung and blood so that the content of metal elements in the body fluctuates.

Levels and variation of radon equilibrium factor in an office of Nanning city / 中华放射医学与防护杂志

Objective:To study the levels and variation of equilibrium factor in indoor environment.Methods:A one-year continuous measurement of radon concentration and equilibrium equivalent radon concentration was carried out in an indoor office building of Nanning city. The effective data acquisition rates of radon gas and radon progeny were 99.9% and 86.7%, respectively.Results:The annual average activity concentration and equilibrium equivalent radon concentration in indoor environment were (50.9±20.7)and (15.5±10.1)Bq/m 3, both of which had the same diurnal and seasonal variation. The average annual value of equilibrium factor was 0.30±0.12, showing no obvious diurnal variation. The distribution of monthly mean value of equilibrium factor showed a similar trend to that of radon and radon progeny. The highest and the lowest value appeared in November and June, respectively, with 0.47±0.24 and 0.19±0.06. Conclusions:Due to the large variation range of monthly mean value of equilibrium factor in indoor environment, when annual effective dose of radon exposure was estimated based on radon gas concentration, attention should be paid to choose the quantity value of equilibrium factor and the uncertainty caused by the change of equilibrium factor should be considered.

Natural radioactive level in raw coal of coal mines in some regions of China / 中国辐射卫生

Objective To understand the activity concentrations of natural radionuclides 40K, 226Ra, 232Th, and 238U in raw coal of coal mines in some regions of China, and to explore the correlation between ore with different activity concentrations and the concentration of radon and its progeny in the workplace. Methods Raw coal samples were collected in twelve coal mines in five provinces, and the activity concentrations of 40K, 226Ra, 232Th, and 238U were measured by a high-purity germanium γ-ray spectrometric system. Results The activity concentrations of four natural radionuclides in the raw coal samples of twelve coal mines were all lower than 1000 Bq/kg, and the activity concentration of 238U in one coal mine was close to 100 Bq/kg. The content of 40K, 226Ra, 232Th, and 238U in different coal mines varied greatly, but 226Ra, 232Th, and 238U were basically at the same level in the same coal mine. Conclusion None of the 12 coal mines belong to radio active mines. One of the coal mines investigated has the activity concentrations of 226Ra, 232Th, and 238U close to the standard limit for restricted-use management mines. It is suggested to study the correlation between the content of 226Ra in raw ore, intermediate products, tailings(slag), or other residues and the concentration of radon and its progeny in mines. Monitoring and protection of radon and its progeny in the decay chain should be strengthened for coal mines with high activity concentrations of natural radionuclides 226Ra, 232Th, and 238U.

Protective effect of the Chinese medicine composition on the radon exposure induced injuries in mice lung and bronchial epithelial cells / 中华放射医学与防护杂志

Objective:To explore the effect of a Chinese medicinal composition ( Xiadanqi) on the prevention of radon exposure induced injuries of lung in vitro and in vivo. Methods:Mice were randomly divided into three groups of blank control group, radon-exposed group alone and radon-exposed group intervened with Chinese medicinal composition. The pathological changes of lung tissues in each group after 120 WLM were observed by HE and Masson staining, and the expressions of α-SMA protein and Vimentin protein in lung tissues were detected by immunohistochemistry staining. The levels of oxidative stress in lung tissue of each group were detected with SOD and MDA kits. At the same time, a radon exposed cell model and a radon exposure + Xiadanqi intervention cell model were constructed using an ecological radon chamber. The cell adhesion abilities of different groups were detected by an adhesion kit. The cell migration ability of each group was determined by the transwell migration experiment. The expression of E-cadherin and Vimentin protein was detected by Western blot. Results:Compared with the radon exposure group, the concentration of MDA was decreased ( t=4.43, P<0.05), the activity of SOD was increased ( t=3.22, P<0.05), and α-SMA and Vimentin protein expressions were decreased ( t=3.08, 7.57, P<0.05) in lung tissue of mice intervened with 2 mg/g Xiadanqi. In vitro, compared with radon exposure group, the migration ability was reduced ( t=4.78, 13.01, P<0.05), the cell adhesion property was enhanced ( t=3.41, 12.55, P<0.05), the expression of E-cadherin protein was increased ( t=2.96, 19.57, P<0.05), and the expression of Vimentin protein was obviously reduced ( t=21.00, 33.32, P<0.05) in radon-exposed cells with the treatment of Chinese medicine (150 μg/ml and 200 μg/ml). Conclusions:The Chinese medicinal composition ( Xiadanqi) has a certain radioprotective effect on radon exposure induced injury by reducing oxidative stress, attenuating EMT and fibrosis, and thus it may be applied as a protective agent for radon induced injury.

Preliminary investigation of radon concentration in drinking water in 31 cities of China / 中华放射医学与防护杂志

Objective:To obtain the distribution characteristics of radon levels in drinking water in cities of China and analysis their influencing factors.Methods:A total of 31 cities were selected and 406 tap water samples were collected in accordance with the sampling plan based on administrative division. Radon concentrations in the water samples were determined by using RAD7 H 2O measuring devices, and the closed loop liquid-gas balance method and grab method . The radon concentrations in the gas loop were measured by using semiconductor detector. After four measurement periods, radon concentrations in water were calculated. Results:The arithmetic mean of radon concentrations in drinking water from 31 cities was (4.92±9.44) Bq/L and the geometric mean (0.71±7.77) Bq/L, ranging from less than the lower detection limit (LLD) to 43.15 Bq/L. For 84.2% of drinking water samples, radon concentrations were less than US EPA recommended 11.1 Bq/L, all lower than the EU-recommended value of 100 Bq/L.Conclusions:The radon concentrations in drinking water are higher in northeastern, northwestern, southwestern, northern China than those in southern, central China and eastern China. The factors influencing radon concentrations in drinking water are closely related to geological structure and water source type. Compared with the global values, the radon concentrations in drinking water in our cities are low and safe in general in China.

Building management and effect evaluation of high radon in geothermal field / 中国辐射卫生

Objective To explore the source and control of radon in high radon houses in geothermal fields; Methods Radon concentration in indoor and soil was measured by ATD detector in winter and summer; radionuclides in building materials were measured by gamma-ray spectrometry; radionuclides dose rates of building materials were measured by 6150 A D/ 6H X-γ ray detector; and radon reduction technology was applied to one of the houses;Results The average radon concentrations in 32 rooms were （106.4 ± 63.7） Bq/m3 (summer) and （421.3 ± 138.2） Bq/m3 (winter), and the concentrations in 12.5% (summer) and 96.9% (winter) of the rooms exceed 150 Bq/m3. The average radon concentration in soil around buildings was 12890 Bq/m3 (n = 24), which is 1.7 times of the typical soil radon concentration in Beijing (7600 Bq/m3). After soil decompression, the radon concentration in the house could be reduced to less than 100 Bq/m3. The radon reduction rates of active decompression and passive decompression were 94.6% and 71.4%, respectively. Conclusion The effect of soil decompression on reducing radon concentration in the bottom rooms is obvious. Attention should be paid to the radon in residential environment of geothermal field.

Investigation and analysis of indoor residential radon concentration in typical areas of Hubei Province / 公共卫生与预防医学

Objective To investigate the residential radon concentration in typical areas of Hubei Province and assess the dose hazards of radon to human body. Methods According to geographical location, five cities including Wuhan, Enshi, Shiyan, Xianning and Daye were selected, and the stratified cluster sampling and monitoring were conducted in accordance with the residential building structure. From April to July, 2019, RSKS standard detectors were placed in the bedroom or living room of the tested families. After continuously sampling for three months, those detectors were returned back to the laboratory for test readings using Radosys system. Results A total of 651 detectors were deployed in 577 households of 70 communities, and 634 detectors were recovered. The recovery rate of detectors was 97.4%. The indoor residential radon concentration in Hubei Province showed a logarithmic normal distribution, with a median (25% quantile and 75% quantile) of 40.52 (29.13,64.74) Bq/m3 and an annual effective dose of 2.02 mSv. The indoor radon concentrations in Wuhan and Enshi were significantly higher than those in Shiyan, Xianning and Daye (P<0.05). The indoor radon concentrations in brick wood or civil structures were significantly higher than those in reinforced concrete structures (P<0.05), and indoor radon concentration in the first floor was significantly higher than those in other floors (P<0.05). The indoor radon concentrations after 2010 were significantly lower than those between 2001 and 2010 (P<0.05). Conclusion The number of households with indoor radon concentrations exceeding the national limit in newly-built buildings accounted for 10.1%; The indoor residential radon concentration levels of in Hubei Province were influenced by building structure, age and floor.