An assessment of radon in groundwater in new york state

ABSTRACT: A set of 317 samples collected from wells throughout New York State (excluding Long Island) from 2003 through 2008 was used to assess the distribution of radon gas in drinking water. Previous studies have documented high concentrations of radon in groundwater from granitic and metamorphic bedrock, but there have been only limited characterizations of radon in water from sedimentary rock and unconsolidated sand-and-gravel deposits in New York. Approximately 8% of the samples from bedrock wells exceed 89 Bq L (eight times the proposed regulatory limit), but only 2% of samples from sand-and-gravel wells exceed 44 Bq L. Specific metamorphic and sedimentary rock formations in New York are associated with the high radon concentrations, indicating that specific areas of New York could be targeted with efforts to reduce the risk of exposure to radon in groundwater. Additionally, radon in groundwater from the sand-and-gravel aquifers was found to be directly correlated to radon in indoor air when assessed by county.     

Occupational doses from radon in Spanish spas

Recent international recommendations have included exposure to natural radiation as one of the sources to monitor in certain occupationally exposed groups. Among those mentioned are workers in thermal spas, who may be exposed to high radiation doses due to the high concentration of radon in the indoor air of the spa. This paper presents the methodology and the results of an evaluation of radiation doses to the staff in different thermal spas in Spain. Different series of samples were collected and measurements made for the radon concentrations in water in 54 spas and in air in 20 spas. In six of the latter group, the air radon concentration was studied in different working areas occupied by the employees. The radon concentrations in water were between <2 and 775 x 10(3) Bq m(-3). The radon concentrations in air were between <10 and 5,200 Bq m(-3). The latter were used to estimate the dose received by each occupational group in the spa by taking into account the radon concentration in their main working area. By means of an exposure-dose conversion factor of 1.43 Sv per J h m(-3), the estimated effective doses were found to lie between 1 and 44 mSv y(-1). This upper limit is higher than the recommended annual limit of 20 mSv y(-1) for an occupational dose.     

降札温泉空气氡浓度水平调查

目的在既往调查的基础上,进一步了解当地居民、游客、治疗疾病的患者的洗浴模式等情况,并对当地的室内外氡浓度进行测量。方法采用ATD短期累积测量法和连续测量法测量室内外氡浓度,并与国家相关标准进行对比。结果室内外氡浓度几乎全部高于电离辐射防护与辐射源安全基本标准(GB18871-2002)中的住宅中氡持续照射的优化行动水平400Bq/m3(平衡因子0.4)。部分浴室中氡浓度高于地热水应用中放射卫生防护标准(GBZ124-2002)中地热水浴疗室平衡当量氡浓度400Bq/m3的控制限值。结论降札温泉室内外氡浓度水平非常高,会对附近的居民、游客和患者的健康造成影响。     

Contribution of 222Rn in domestic water supplies to 222Rn in indoor air in Colorado homes.

The contribution of 222Rn from domestic water wells to indoor air was investigated in a study of 28 houses near Conifer, CO. Air concentrations determined by alpha-track detectors (ATDs) and continuous radon monitors were compared with the predictions of a single-cell model. In many of the houses, the water supply was shown to contribute significantly to levels of indoor 222Rn. The data from the ATD study were augmented with a continuous monitoring study of a house near Lyons, CO. The well water in that house has the highest known concentration of 222Rn in water yet reported (93 MBq m-3). The temporal pattern in the indoor 222Rn concentration corresponds to water-use records. In general, it is difficult to quantify the proportion of indoor radon attributable to water use. Several lines of evidence suggest that the single-cell model underestimates this proportion. Continuous-monitoring data, although useful, are impractical due to the cost of the equipment. We propose a protocol for 222Rn measurement based on three simultaneous integrating radon detectors that may help estimate the proportion of indoor 222Rn derived from the water supply.     

Radon in Irish schools: the results of a national survey.

This paper presents the results of a survey of radon concentrations in Irish primary and post-primary schools. The objective of this survey was to assess the distribution of radon in Irish schools and to identify those requiring remedial work to reduce radon exposure to children and staff. All primary and post-primary schools were invited to participate in the survey. Indoor radon concentrations were measured during the academic year using integrating passive alpha track-etch detectors with a measurement period from three to nine months. The survey was carried out on a phased basis from 1998 to 2004 and is one of the most comprehensive of its kind undertaken in Europe. Measurements were completed in 38 531 ground floor classrooms and offices in 3826 schools, representing over 95% of the approximate 4000 primary and post-primary schools in Ireland. Of these, 984 schools had radon concentrations greater than 200 Bq m(-3) in 3028 rooms and 329 schools had radon concentrations in excess of 400 Bq m(-3) in 800 rooms. The average radon concentration in schools was 93 Bq m(-3). This results in an annual average effective dose to an Irish child from exposure to radon of 0.3 mSv per year, assuming that the long-term radon concentration is equal to the radon concentration present during the working hours and that the annual average occupancy is 1000 h per year. A programme of remediation of schools with radon concentrations above 200 Bq m(-3) has been put in place.     

云南省某矿区氡浓度水平调查分析

目的 调查云南省某锡矿、铜矿及非矿区居室内空气中的氡浓度以及相应采样点自来水中氡浓度，估算人体受照剂量。方法 径迹法测量锡矿、铜矿井下、地上工作场所空气中的氡浓度，使用RAD7仪器连续测量法测得居室内空气中氡浓度、RAD7水氡测量系统测量自来水氡浓度。评估不同来源氡所致受照剂量的贡献。结果 锡矿的矿下、地上工作场所空气平均氡浓度分别为（7 473 ±3 105）Bq·m⁻³和（332 ±238）Bq·m⁻³，其所致年剂量贡献分别为（29.44 ±12.23）mSv和（2.50 ±1.79）mSv；铜矿井下、地上工作场所空气中氡浓度分别为（4 477 ±5 152）Bq·m⁻³和（110 ±32）Bq·m⁻³，其所致年剂量贡献分别为（17.64 ±20.30）mSv和（0.83 ±0.24）mSv；居室空气氡浓度（76 ±33）Bq·m⁻³及年剂量贡献（2.01 ±0.87）mSv。铜矿及锡矿的自来水氡浓度测量结果分别为（1.66 ±2.00）Bq·L⁻¹和（3.94 ±1.81）Bq·L⁻¹，高于市内32个采样点自来水氡浓度（0.39 ±0.21）Bq·L⁻¹。结论 目前所测区域水氡所致剂量贡献相对较小，锡矿、铜矿区井下工作场所空气氡浓度值得关注，应重视对矿工使用防护用具的宣传教育工作。     

Prevention measures against radiation exposure to radon in well waters: analysis of the present situation in Finland

Naturally occurring radioactive elements are found in all groundwaters, especially in bedrock waters. Exposure to these radioactive elements increases the risk of cancer. The most significant of these elements is radon which, as a gas, is mobile and dissolves in groundwater. In Finland, water supply plants are obliged to carry out statutory monitoring of the water quality, including radon. Monitoring of private wells, however, is often neglected. In this paper, we outline the problem by reviewing the outcomes of the studies conducted in Finland since the 1960s. We also summarise the development of legislation, regulations and political decisions made so far that have affected the amount of public exposure to radon in drinking water. A review of the studies on radon removal techniques is provided, together with newly obtained results. New data on the transfer of radon from water into indoor air are presented. The new assessments also take into account the expanding use of domestic radionuclide removal units by Finnish households.     

Exposure to atmospheric radon.

We measured radon (222Rn) concentrations in Iowa and Minnesota and found that unusually high annual average radon concentrations occur outdoors in portions of central North America. In some areas, outdoor concentrations exceed the national average indoor radon concentration. The general spatial patterns of outdoor radon and indoor radon are similar to the spatial distribution of radon progeny in the soil. Outdoor radon exposure in this region can be a substantial fraction of an individual's total radon exposure and is highly variable across the population. Estimated lifetime effective dose equivalents for the women participants in a radon-related lung cancer study varied by a factor of two at the median dose, 8 mSv, and ranged up to 60 mSv (6 rem). Failure to include these doses can reduce the statistical power of epidemiologic studies that examine the lung cancer risk associated with residential radon exposure.     

Indoor radon and well water radon in Virginia and Maryland

The domestic use of radioactive water has long been a cause for concern, but only a few studies have examined prolonged exposure to radionuclide concentrations found in natural settings. This paper reports on the indoor radon concentrations from 1,500 homes in northern Virginia and southern Maryland and well water radon from 700 homes in the same area. Indoor radon concentrations are almost all between 1 and about 40 pCi/L. The winter season shows the highest values with about 40% of the homes over the US EPA action level of 4.0 pCi/L. The summer season shows the lowest values with about 25% of the homes over this level. This seasonal variation is related to home ventilation. Waterborne radon in homes with private well ranges from about 100 pCi/L to about 8,000 pCi/L. In small homes, indoor radon can be significantly increased by outgassing of the home water supply, even at water radon levels of less than 10,000 pCi/L.     

210Po implanted in glass surfaces by long term exposure to indoor radon

Recent epidemiologic investigations of the relationship between residential radon gas exposure and lung cancer relied on contemporary radon gas measurements to estimate past radon gas exposures. Significant uncertainties in these exposure estimates can arise from year-to-year variation of indoor radon concentrations and subject mobility. Surface implanted 210Po has shown potential for improving retrospective radon gas exposure estimates. However, in previous studies, the ability of implanted 210Po activity to reconstruct cumulative radon gas exposure was not tested because glass was not available from homes with known radon-gas concentration histories. In this study, we tested the validity of the retrospective radon gas reconstruction using implanted 210Po surface activity by measuring glass surfaces from homes whose annual-average radon gas concentrations had been measured almost every year during two decades. Regression analysis showed a higher correlation between measured surface activity and cumulative radon gas exposure in these homes (R2>0.8) than was observed in homes where only contemporary radon gas measurements were available. The regression slope (0.57 ky m(-1)) was consistent with our earlier retrospective results. Surface activity measurements were as reliable for retrospective radon gas exposure reconstruction as yearlong gas measurements. Both methods produced estimates that were within 25% of the long-term average radon gas concentrations in a home. Surface measurements can be used for home screening tests because they can provide rapid, reliable estimates of past radon gas concentrations. Implanted 210Po measurements are also useful in retrospective epidemiologic studies that include participants who may have been exposed to highly variable radon concentrations in previously occupied or structurally modified homes.     

室内氡的危害研究进展

阐述了人类赖以生存的环境中氡的来源、性质、进入人体的途径及致病机制和主要危害。同时介绍了世界各国在氡研究领域中的现状和最新进展情况。资料表明：随着经济的发展，住宅的条件逐步得到改善，特别是家庭空调的使用，以及不适当建筑材料或装饰材料的使用，已经使室内氡的问题成为人人都要面临的普遍性问题。介绍了过去10年各国对氡的研究情况，包括室内空气中氡的浓度，它给人们带来的内照射剂量，以及为减少氡所带来的危害要采取的补救措施和降低室内氡的主要技术方法。     

IAEA/EPA international climatic test program for integrating radon detectors. International Atomic Energy Agency/Environmental Protection Agency.

As an element of the joint IAEA-EPA International Radon Metrology Evaluation Program, a climatic test of long-term integrating radon detectors was conducted at the U.S. EPA Radiation and Indoor Environments National Laboratory. The objective of this study was to test the performance of commonly used commercially available long-term 222Rn detector systems under extreme climatological conditions using filtered polycarbonate CR-39 plastic analyzed by the manufacturer using the track-etch method, unfiltered LR-115 film analyzed by the manufacturer, and Teflon based electrets analyzed in the field by EPA using the manufacturer's equipment. The EPA environmental radon chambers were used to expose detectors to extreme cold and dry (less than 4.0 degrees C air temperature and 25% relative humidity) and hot and humid (greater than 35 degrees C air temperature and 85% relative humidity) climatic conditions. During phase I detectors were exposed to low temperatures and low humidities, and during phase II detectors were exposed to high temperatures and high humidities. Typical indoor equilibrium fractions (near 50%) and radon concentrations of about 150 Bq m(-3) were maintained for each phase, which lasted 90 d. The results indicated that the optimal detector for extreme climatic conditions is dependent on the relative importance of bias and precision. Overall, however, the filtered track-etch type detector produced the most reliable results under the extreme conditions.     

Indoor radon and lung cancer in France

BACKGROUND: Several case-control studies have indicated an increased risk of lung cancer linked to indoor radon exposure; others have not supported this hypothesis, partly because of a lack of statistical power. As part of a large European project, a hospital-based case-control study was carried out in 4 areas in France with relatively high radon levels. METHODS: Radon concentrations were measured in dwellings that had been occupied by the study subjects during the 5- to 30-year period before the interview. Measurements of radon concentrations were performed during a 6-month period using 2 Kodalpha LR 115 detectors (Dosirad, France), 1 in the living room and 1 in the bedroom. We examined lung cancer risk in relation to indoor radon exposure after adjustment for age, sex, region, cigarette smoking, and occupational exposure. RESULTS: We included in the analysis 486 cases and 984 controls with radon measures in at least 1 dwelling. When lung cancer risk was examined in relation to the time-weighted average radon concentration during the 5- to 30-year period, the estimated relative risks (with 95% confidence intervals) were: 0.85 (0.59-1.22), 1.19 (0.81-1.77), 1.04 (0.64-1.67), and 1.11 (0.59-2.09) for categories 50-100, 100-200, 200-400, and 400+ becquerels per cubic meter (Bq/m), respectively (reference <50 Bq/m). The estimated relative risk per 100 Bq/m was 1.04 (0.99-1.11) for all subjects and 1.07 (1.00-1.14) for subjects with complete measurements. CONCLUSIONS: Our results support the presence of a small excess lung cancer risk associated with indoor radon exposure after precise adjustment on smoking. They are in agreement with results from some other indoor radon case-control studies and with extrapolations from studies of underground miners.     

Anomalously high radon concentrations in dwellings located on permeable glacial sediments.

Indoor radon concentrations were measured in different seasons in 104 dwellings located on a highly permeable ice-marginal moraine in Kinsarvik, Western Norway. The measurements revealed the highest indoor radon levels ever detected in Norway and extreme variations in seasonal and short-term indoor radon levels. Annual average indoor radon concentrations up to 56 000 Bq m(-3) and a mean value of 4340 Bq m(-3) for the whole residential area are reported. By using the ICRP conversion factors to effective dose, these indoor radon values correspond to a total annual effective dose of 930 mSv and 72 mSv, respectively. By using the conversion as recommended by UNSCEAR, the effective doses would be about 50% higher. The indoor radon concentrations are found to be strongly influenced by thermally induced flows of radon-bearing soil air directed towards the upper part of the ice-marginal deposit in winter and towards the area of lowest elevation in summer. The pattern of seasonal variations observed suggests that in areas where thermal convection may occur, annual average indoor radon levels should be derived from measurements performed both in summer and in winter.     

Building-specific factors affecting indoor radon concentration variations in different regions in Bulgaria

The study was conducted to assess the spatiality of the building factors’ effect on air quality through evaluation of indoor radon concentration in areas with different geology and geographical position. For that matter, a survey of indoor radon concentration was carried out in 174 kindergartens of three Bulgarian cities. The time-integrated measurements were performed in 777 ground floor rooms using alpha tract detectors, exposed for 3 months in cold period of 2014. The results of indoor radon concentrations vary from 20 to 1117 Bq/m³. The differences in the mean radon concentrations measured in the different cities were related to geology. The effect of building-specific factors: elevator, basement, mechanical ventilation, type of windows, number of floors, building renovation, building materials, type of room, type of heating, construction period, and availability of foundation on radon concentration variations was examined applying univariate and multivariate analysis. Univariate analysis showed that the effects of building-specific factors on radon variation are different in different cities. The influence of building factors on radon concentration variations was more dominant in inland cities in comparison to the city situated on the sea coast. The multivariate analysis, which was applied to evaluate the impact of building factors simultaneously, confirmed this influence too.     

A survey of 222Rn concentrations in dwellings of the town of Metsovo in north-western Greece

A radon survey has been carried out of indoor radon concentrations in dwellings located in the town of Metsovo, in north-western Greece. To measure indoor radon concentrations, CR-39 detectors were installed in randomly selected houses and were exposed for about 3 mo, during summer and winter. Gamma spectroscopy measurements of the soil's radium content also were performed. The indoor radon concentration levels varied from 17.6 to 750.4 Bq m(-3), while the radium concentration of soil varied from 4.9 to 97.1 Bq m(-3). Seasonal variation of the radon levels and the influence of house features and soil are discussed.     

降氡方法在室内氡污染治理中的应用与分析

目的 探索降低住宅氡及其子体浓度水平的合适方法.方法 选取3个房间分别采取自然通风、空气净化器、密封屏蔽的措施后,使用EQF3120型氡及其子体测量仪测量室内氡及其子体浓度,α核径迹探测器测量室内氡浓度,并比较不同方法的降氡效果.结果 自然通风2～10 h后,房间内氡、结合态氡子体和未结合态氡子体浓度平均降低率分别为8...     

An improved model for the reconstruction of past radon exposure

If the behavior of long-lived radon progeny was well understood, measurements of these could be used in epidemiological studies to estimate past radon exposure. Field measurements were done in a radon-prone area in the Ardennes (Belgium). The surface activity of several glass sheets was measured using detectors that were fixed on indoor glass surfaces. Simultaneously the indoor radon concentration was measured using diffusion chambers. By using Monte Carlo techniques, it could be proven that there is a discrepancy between this data set and the room model calculations, which are normally used to correlate surface activity and past radon exposure. To solve this, a modification of the model is proposed.     

南宁市医院室内氡浓度及γ辐射水平所致工作人员剂量

目的 了解南宁市医院放射科与核医学科室内氡浓度和γ照射量率水平,估算工作人员受照剂量,为辐射防护管理提供依据。方法 采用ATD累积氡探测器和FH40G环境X、γ剂量率仪测量室内外氡浓度和γ照射量率。结果 核医学、放射科地下和地面工作场所、工作人员和居民受照剂量分别是1.98 mSv、1.84 mSv、1.62 mSv、1.48 mSv和1.49 mSv。结论 核医学科工作人员受到的附加剂量主要与放射性同位素的用量与防护条件有关。放射科工作人员剂量增高的原因主要来自氡污染产生的内照射。     

苏州市室内氡浓度水平及其影响因素研究

目的：了解苏州市室内222Rn浓度及其影响因素.方法：使用固体径迹探测器,调查苏州市8个行政区域160户居民室内222Rn浓度,调查时间为1年,每3个月为一周期,即春、夏、秋、冬四季.探测器回收后,在6.25 mol/L的NaOH溶液中,恒温90℃蚀刻5 h,在显微镜下读数.结果：年平均222Rn浓度为29.9±21.0 Bq·m^-3;不同季节、不同通风时间、不同建筑结构及建筑年代的室内222Rn浓度存在显著差异（P〈0.05）;结论：苏州市居民室内年平均222Rn浓度低于国家标准〈电离辐射防护与辐射源安全基本标准（GB 18871-2002）〉;季节、通风时间、建筑材料是室内222Rn浓度的主要影响因素.