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Sample records for radon exposure chambers

  1. Quality assurance for radon exposure chambers at the National Air and Radiation Environmental Laboratory, Montgomery, Alabama

    SciTech Connect

    Semler, M.O.; Sensintaffar, E.L.

    1993-12-31

    The Office of Radiation and Indoor Air, U.S. Environmental Protection Agency (EPA), operates six radon exposure chambers in its two laboratories, the National Air and Radiation Environmental Laboratory (NAREL) in Montgomery, Alabama, and the Las Vegas Facility, Las Vegas, Nevada. These radon exposure chambers are used to calibrate and test portable radon measuring instruments, test commercial suppliers of radon measurement services through the Radon Measurement Proficiency Program, and expose passive measurement devices to known radon concentrations as part of a quality assurance plan for federal and state studies measuring indoor radon concentrations. Both laboratories participate in national and international intercomparisons for the measurement of radon and are presently working with the National Institute of Standards and Technology (NIST) to receive a certificate of traceability for radon measurements. NAREL has developed an estimate of the total error in its calibration of each chamber`s continuous monitors as part of an internal quality assurance program. This paper discusses the continuous monitors and their calibration for the three chambers located in Montgomery, Alabama, as well as the results of the authors intercomparisons and total error analysis.

  2. Exposure to atmospheric radon.

    PubMed Central

    Steck, D J; Field, R W; Lynch, C F

    1999-01-01

    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. Images Figure 1 Figure 2 Figure 3 Figure 4 PMID:9924007

  3. Exposure to atmospheric radon.

    PubMed

    Steck, D J; Field, R W; Lynch, C F

    1999-02-01

    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.

  4. [Radon and domestic exposure].

    PubMed

    Melloni, B; Vergnenègre, A; Lagrange, P; Bonnaud, F

    2000-12-01

    Radon is a noble gas derived from the decay of radium, which itself is a decay product of uranium. The decay products of radon can collect electrostatically on dust particles in the air and, if these particles are inhaled and attach to bronchial epithelium, produce a high local radiation dose. Alpha particles can induce DNA double-strand breaks and the development of cancer. A causal relation between lung cancer and radon exposure and its progeny has been demonstrated in epidemiological studies of miners. Radon exposure became a public health issue almost 15 years ago. Most radon exposure occurs indoors, predominantly in the home. There is however, a wide range of radon concentration values in different countries. The highest level occurs in areas with granite and permeable soils. The risk for smoking, the leading cause of lung cancer, is far greater than for radon, the second leading cause. The estimates obtained from case-control studies of indoor radon are very contradictory. Scientific knowledge of effects of low levels of exposure to radon and the role of cigarette smoking, as a combined factor, must be studied. Smoking and radon probably interact in a multiplicative fashion.

  5. Exposure chamber

    DOEpatents

    Moss, Owen R.; Briant, James K.

    1983-01-01

    An exposure chamber includes an imperforate casing having a fluid inlet at the top and an outlet at the bottom. A single vertical series of imperforate trays is provided. Each tray is spaced on all sides from the chamber walls. Baffles adjacent some of the trays restrict and direct the flow to give partial flow back and forth across the chambers and downward flow past the lowermost pan adjacent a central plane of the chamber.

  6. The Japanese Radon and Thoron Reference Chambers

    SciTech Connect

    Tokonami, Shinji; Ishikawa, Tetsuo; Sorimachi, Atsuyuki; Takahashi, Hiroyuki; Miyahara, Nobuyuki

    2008-08-07

    Passive detectors used for large-scale and long-term surveys are generally calibrated in a well-controlled environment such as a radon chamber. It has been also pointed out that some of them are sensitive to thoron. Thus it is necessary to check the thoron contribution to the detector response with the proposed or similar test before practical use. The NIRS accommodates radon/aerosol and thoron chambers for quality assurance and quality control of radon measurements. Thus both chambers work so well that they can supply us with the calibration technique and consequently, a good level of knowledge of the radon and thoron issue.

  7. Exposure chamber

    DOEpatents

    Moss, Owen R.

    1980-01-01

    A chamber for exposing animals, plants, or materials to air containing gases or aerosols is so constructed that catch pans for animal excrement, for example, serve to aid the uniform distribution of air throughout the chamber instead of constituting obstacles as has been the case in prior animal exposure chambers. The chamber comprises the usual imperforate top, bottom and side walls. Within the chamber, cages and their associated pans are arranged in two columns. The pans are spaced horizontally from the walls of the chamber in all directions. Corresponding pans of the two columns are also spaced horizontally from each other. Preferably the pans of one column are also spaced vertically from corresponding pans of the other column. Air is introduced into the top of the chamber and withdrawn from the bottom. The general flow of air is therefore vertical. The effect of the horizontal pans is based on the fact that a gas flowing past the edge of a flat plate that is perpendicular to the flow forms a wave on the upstream side of the plate. Air flows downwardly between the chamber walls and the outer edges of the pan. It also flows downwardly between the inner edges of the pans of the two columns. It has been found that when the air carries aerosol particles, these particles are substantially uniformly distributed throughout the chamber.

  8. An Environmentally Controlled Chamber for the Study of Radon Detection

    DTIC Science & Technology

    1991-03-01

    constant coefficients respectively. Concentrations calculated using this equation should be correct to within 2.8 pCi/liter. Radon Concentration (pCi/t...physical volume of the radon chamber is approximately one-half of the effective volume because of the delay in emanations of the radon from the dry...ENVIRONMENTALLY CONTROLLED CHAMBER FOR THE STUDY OF RADON DETECTION THESIS William R. Wharton, Jr, Capt, USAF AFIT/EN/GNE/9 IM-11 I I Approved for public release

  9. A double chamber system for producing constant radon concentration.

    PubMed

    Haider, B; Peter, J

    1995-01-01

    An experimental arrangement of a radon chamber with an intrinsic constancy of the relative radon concentration is described. The system consists of a reference chamber and an auxiliary storage chamber. The only active device is a timer-controlled pump or valve which feeds radon gas from the storage into the reference chamber. The switching pattern of the timer is extracted from model calculations and theoretically performs an exact compensation of the radon loss by radioactive decay. If the calculations are done in real time and online, every known external event influencing the radon concentration can be compensated. This paper presents a simple timer circuit and a computer code which generates the timer program. The influence of the air flow stability and the leakage of the chambers are discussed. It is planned to apply this theoretical approach to provide a constant radon gas concentration for an actual chamber.

  10. Radon/radon daughter environmental chamber located in the northwest end of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Radon/radon daughter environmental chamber located in the northwest end of building. VIEW LOOKING WEST - Department of Energy, Grand Junction Office, Building No. 32, 2597 B3/4 Road, Grand Junction, Mesa County, CO

  11. Radon exposures in a Jerusalem public school.

    PubMed Central

    Richter, E D; Neeman, E; Fischer, I; Berdugo, M; Westin, J B; Kleinstern, J; Margaliot, M

    1997-01-01

    In December 1995, ambient radon levels exceeding 10,000 Bq/m3 were measured in a basement shelter workroom of a multilevel East Talpiot, Jerusalem, public elementary school (six grades, 600 students). The measurements were taken after cancers (breast and multiple myeloma) were diagnosed in two workers who spent their workdays in basement rooms. The school was located on a hill that geologic maps show to be rich in phosphate deposits, which are a recognized source for radon gas and its daughter products. Levels exceeding 1000,000 Bq/m3 were measured at the mouth of a pipe in the basement shelter workroom, the major point of radon entry. The school was closed and charcoal and electret ion chamber detectors were used to carry out repeated 5-day measurements in all rooms in the multilevel building over a period of several months. Radon concentrations were generally higher in rooms in the four levels of the building that were below ground level. There were some ground-level rooms in the building in which levels reached up to 1300 Bq/m3. In rooms above ground level, however, peak levels did not exceed 300 Bq/m3. Exposure control based on sealing and positive pressure ventilation was inadequate. These findings suggested that radon diffused from highly contaminated basement and ground-floor rooms to other areas of the building and that sealing off the source may have led to reaccumulation of radon beneath the building. Later, subslab venting of below-ground radon pockets to the outside air was followed by more sustained reductions in indoor radon levels to levels below 75 Bq/m3. Even so, radon accumulated in certain rooms when the building was closed. This sentinel episode called attention to the need for a national radon policy requiring threshold exposure levels for response and control. A uniform nationwide standard for school buildings below 75 Bq/m3 level was suggested after considering prudent avoidance, the controversies over risk assessment of prolonged low

  12. Intercomparison of active, passive and continuous instruments for radon and radon progeny measurements in the EML chamber and test facility

    SciTech Connect

    George, A.C.; Knutson, E.O.; Tu, K.W.; Fisenne, I.M.

    1995-12-01

    The results from the May 1995 Intercomparison of Active, Passive and Continuous Instruments for Radon and Radon Progeny Measurement conducted in the EML radon exposure and test facility are presented. Represented were 13 participants that measure radon with open faced and diffusion barrier activated carbon collectors, 10 with nuclear alpha track detectors, 9 with short-term and long-term electret/ionization chambers, and 13 with active and passive commercial electronic continuous monitors. For radon progeny, there were four participants that came in person to take part in the grab sampling methodology for measuring individual radon progeny and the potential alpha energy concentration (PAEC). There were 11 participants with continuous and integrating commercial electronic instruments that are used for measuring the PAEC. The results indicate that all the tested instruments that measure radon fulfill their intended purpose. All instruments and methods used for grab sampling for radon progeny did very well. However, most of the continuous and integrating electronic instruments used for measuring the PAEC or working level appear to underestimate the potential risk from radon progeny when the concentration of particles onto which the radon progeny are attached is <5,000 cm{sup -3}.

  13. Radiological risk of building materials using homemade airtight radon chamber

    SciTech Connect

    Khalid, Norafatin; Majid, Amran Ab.; Yahaya, Redzuwan; Yasir, Muhammad Samudi

    2014-02-12

    Soil based building materials known to contain various amounts of natural radionuclide mainly {sup 238}U and {sup 232}Th series and {sup 40}K. In general most individuals spend 80% of their time indoors and the natural radioactivity in building materials is a main source of indoor radiation exposure. The internal exposure due to building materials in dwellings and workplaces is mainly caused by the activity concentrations of short lived {sup 222}Radon and its progenies which arise from the decay of {sup 226}Ra. In this study, the indoor radon concentration emanating from cement brick, red-clay brick, gravel aggregate and Portland cement samples were measured in a homemade airtight radon chamber using continuous radon monitor 1029 model of Sun Nuclear. Radon monitor were left in the chamber for 96 hours with an hour counting time interval. From the result, the indoor radon concentrations for cement brick, red-clay brick, gravel aggregate and Portland cement samples determined were 396 Bq m{sup −3}, 192 Bq m{sup −3}, 176 Bq m{sup −3} and 28 Bq m{sup −3}, respectively. The result indicates that the radon concentration in the studied building materials have more than 100 Bq m{sup −3} i.e. higher than the WHO action level except for Portland cement sample. The calculated annual effective dose for cement brick, red-clay brick, gravel aggregate and Portland cement samples were determined to be 10 mSv y{sup −1}, 4.85 mSv y{sup −1}, 4.44 mSv y{sup −1} and 0.72 mSv y{sup −1}, respectively. This study showed that all the calculated effective doses generated from indoor radon to dwellers or workers were in the range of limit recommended ICRP action levels i.e. 3 - 10 mSv y{sup −1}. As consequences, the radiological risk for the dwellers in terms of fatal lifetime cancer risk per million for cement brick, red-clay brick, gravel aggregate and Portland cement were calculated to be 550, 267, 244 and 40 persons respectively.

  14. The most recent international intercomparisons of radon and thoron monitors with the NIRS radon and thoron chambers.

    PubMed

    Janik, M; Yonehara, H

    2015-06-01

    The fifth international intercomparison for radon and fourth for thoron monitors were conducted at National Institute of Radiological Sciences (Japan) with the radon and thoron chambers. The tests were made under two different exposures to radon and two exposures (in two rounds due to limited space in the thoron chamber) to thoron. In these most recent intercomparisons, two new graphical methods recommended by the ISO standard, Mandel's h statistic and the Youden plot, were implemented to evaluate the consistency between laboratories and within laboratories.The presented data indicated that the performance quality of laboratories for radon measurement as expressed by the percentage difference parameter has been stable since the first international intercomparison for passive monitors carried out in 2007, and it amounted to around 50 for 10 % of the difference from the reference value. The thoron exercise showed that further development and additional studies to improve its measuring methods and reliability are needed.

  15. Design and Fabrication of A Modern Radon-Tight Chamber for Radon Concentration Measurements

    NASA Astrophysics Data System (ADS)

    Alhalemi, Ahmed; Jaafar, M. S.

    2010-07-01

    A modern radon-tight chamber (RTC) has been designed and fabricated to meet the request and requirements for both the Professional Continuous Radon Monitor (PCRM), and the RAD7 radon detector. The chamber is cubic shaped, made of Perspex with a volume of about 0.125 m3. The RTC was also equipped with a thermometer and a humidity sensor. A pair of gloves was attached on one side of the chamber's lateral opening for operating the PCRM. In addition, a fan was installed to circulate the air, and to distribute the radon gas to ensure homogeneity after the air inside the chamber is evacuated with nitrogen gas. At the end of the monitoring period, the results of the concentration of the radon emanated from a sample placed inside the chamber will then be available in any of three forms: numerical display on the control panel of the radon detector, printed report on the accessory printer, or transferred into a file on a personal computer via the RS-232 Serial port without disturbing the radon concentration inside the chamber. Computer software is provided by the manufacturer for this purpose. The result of analysis was presented in a one-way ANOVA that indicated that the radon concentration means are not difference for the three different positions of the PCRM (P > 0.05). Thus, this RTC can be used to measure the radon concentration and its progeny; in addition, it can be used for research and useful studies on radon exhalation from building materials.

  16. One cubic metre NIST traceable radon test chamber.

    PubMed

    Kotrappa, P; Stieff, F

    2008-01-01

    With the availability of the National Institute of Standards and Technology (NIST) Radon Emanation Standard with a content of approximately 5000 Bq of 226Ra, it is possible to build a flow through a practical radon test chamber. A standard glove box with four gloves and a transfer port is used. Air is pumped through a flow integrator, water jar for humidification and NIST source holder, and into the glove box through a manifold. A derived theoretical expression provides the calculated radon concentration inside the chamber. The calculation includes a derived decay correction due to the large volume and low flow rate of the system. Several calibrated continuous radon monitors and passive integrating electret ion chambers tested in the chamber agreed fairly well with the calculated radon concentrations. The chamber is suitable for handling the calibration of several detectors at the same time.

  17. Intercomparison of active, passive and continuous instruments for radon and radon progeny measurements in the EML chamber and test facility

    SciTech Connect

    Scarpitta, S.C.; Tu, K.W.; Fisenne, I.M.; Cavallo, A.; Perry, P.

    1996-10-01

    Results are presented from the Fifth Intercomparison of Active, Passive and Continuous Instruments for Radon and Radon Progeny Measurements conducted in the EML radon exposure and test facility in May 1996. In total, thirty-four government, private and academic facilities participated in the exercise with over 170 passive and electronic devices exposed in the EML test chamber. During the first week of the exercise, passive and continuous measuring devices were exposed (usually in quadruplicate) to about 1,280 Bq m{sup {minus}3} {sup 222}Rn for 1--7 days. Radon progeny measurements were made during the second week of the exercise. The results indicate that all of the tested devices that measure radon gas performed well and fulfill their intended purpose. The grand mean (GM) ratio of the participants` reported values to the EML values, for all four radon device categories, was 0.99 {plus_minus} 0.08. Eighty-five percent of all the radon measuring devices that were exposed in the EML radon test chamber were within {plus_minus}1 standard deviation (SD) of the EML reference values. For the most part, radon progeny measurements were also quite good as compared to the EML values. The GM ratio for the 10 continuous PAEC instruments was 0.90 {plus_minus} 0.12 with 75% of the devices within 1 SD of the EML reference values. Most of the continuous and integrating electronic instruments used for measuring the PAEC underestimated the EML values by about 10--15% probably because the concentration of particles onto which the radon progeny were attached was low (1,200--3,800 particles cm{sup {minus}3}). The equilibrium factor at that particle concentration level was 0.10--0.22.

  18. Realization of radioactive equilibrium in the KRISS radon chamber.

    PubMed

    Lee, Mo Sung; Park, Tae Soon; Lee, Jong Man

    2013-11-01

    The maintenance of radioactive equilibrium between radon and its decay products in a radon chamber is necessary to calibrate radon decay product monitors. In this study, the activity concentrations of radon decay products have been measured, and mosquito-repellent incense has been used to produce aerosol particles in the chamber. Filter papers with 8 μm pore size were used to collect aerosol in the chamber. The activity concentrations of radon decay products have been evaluated by the Modified Tsivoglou Method. The correction factors due to the differences in counting time requirements of the Modified Tsivoglou Method and the time delay between consecutive measurements have been determined. Finally, the radioactive equilibrium has been confirmed by applying the Bateman equation. © 2013 Elsevier Ltd. All rights reserved.

  19. Radon exposure and oropharyngeal cancer risk.

    PubMed

    Salgado-Espinosa, Tania; Barros-Dios, Juan Miguel; Ruano-Ravina, Alberto

    2015-12-01

    Oropharyngeal cancer is a multifactorial disease. Alcohol and tobacco are the main risk factors. Radon is a human carcinogen linked to lung cancer risk, but its influence in other cancers is not well known. We aim to assess the effect of radon exposure on the risk of oral and pharyngeal cancer through a systematic review of the scientific literature. This review performs a qualitative analysis of the available studies. 13 cohort studies were included, most of them mortality studies, which analysed the relationship between occupational or residential radon exposure with oropharyngeal cancer mortality or incidence. Most of the included studies found no association between radon exposure and oral and pharyngeal cancer. This lack of effect was observed in miners studies and in general population studies. Further research is necessary to quantify if this association really exists and its magnitude, specially performing studies in general population, preferably living in areas with high radon levels.

  20. Potential health effects of indoor radon exposure.

    PubMed Central

    Radford, E P

    1985-01-01

    Radon-222 is a ubiquitous noble gas arising from decay of radium-226 normally present in the earth's crust. Alpha radiation from inhaled short-lived daughters of radon readily irradiates human bronchial epithelium, and there is now good evidence of excess risk of lung cancer in underground miners exposed to higher concentrations. In homes, radon levels are highly variable, showing approximately log-normal distributions and often a small fraction of homes with high concentrations of radon and radon daughters. Factors affecting indoor concentrations include type of bedrock under dwellings, house foundation characteristics, radon dissolved in artesian water, and ventilation and degree of air movement in living spaces. Despite much recent work, exposures to radon daughters by the general public are not well defined. From application of risk assessments in miners to home conditions, it appears that about 25% or more of lung cancers among nonsmokers over the age of 60, and about 5% in smokers, may be attributable to exposure to radon daughters at home. It may be necessary to take remedial action to reduce this hazard in those dwellings with elevated levels of radon, and new construction should take account of this problem. PMID:4085431

  1. Potential health effects of indoor radon exposure.

    PubMed

    Radford, E P

    1985-10-01

    Radon-222 is a ubiquitous noble gas arising from decay of radium-226 normally present in the earth's crust. Alpha radiation from inhaled short-lived daughters of radon readily irradiates human bronchial epithelium, and there is now good evidence of excess risk of lung cancer in underground miners exposed to higher concentrations. In homes, radon levels are highly variable, showing approximately log-normal distributions and often a small fraction of homes with high concentrations of radon and radon daughters. Factors affecting indoor concentrations include type of bedrock under dwellings, house foundation characteristics, radon dissolved in artesian water, and ventilation and degree of air movement in living spaces. Despite much recent work, exposures to radon daughters by the general public are not well defined. From application of risk assessments in miners to home conditions, it appears that about 25% or more of lung cancers among nonsmokers over the age of 60, and about 5% in smokers, may be attributable to exposure to radon daughters at home. It may be necessary to take remedial action to reduce this hazard in those dwellings with elevated levels of radon, and new construction should take account of this problem.

  2. Radon

    EPA Pesticide Factsheets

    Exposure to radon is the second leading cause of lung cancer after smoking. Radon is a colorless, odorless, tasteless and invisible gas produced by the decay of naturally occurring uranium in soil and water.

  3. Radon exhalation rates from building materials using electret ion chamber radon monitors in accumulators.

    PubMed

    Kotrappa, Payasada; Stieff, Frederick

    2009-08-01

    An electret ion chamber (EIC) radon monitor in a sealed accumulator measures the integrated average radon concentration at the end of the accumulation duration. Theoretical equations have been derived to relate such radon concentrations (Bq m(-3) ) to the radon emanation rate (Bq d(-1)) from building materials enclosed in the accumulator. As an illustration, a 4-L sealable glass jar has been used as an accumulator to calculate the radon emanation rate from different granite samples. The radon emanation rate was converted into radon flux (Bq mm(-2) d(-1)) by dividing the emanation rate by surface area of the sample. Fluxes measured on typical, commercially available granites ranged from 20-30 Bq m(-2) d(-1). These results are similar to the results reported in the literature. The lower limit of detection for a 2-d measurement works out to be 7 Bq m(-2) d(-1). Equations derived can also be used for other sealable accumulators and other integrating detectors, such as alpha track detectors.

  4. Exposure to unusually high indoor radon levels

    SciTech Connect

    Rasheed, F.N. )

    1993-03-27

    Unusually high indoor radon concentrations were reported in a small village in western Tyrol, Austria. The authors have measured the seasonal course of indoor radon concentrations in 390 houses of this village. 71% of houses in winter and 33% in summer, showed radon values on the ground floor above the Austrian action level of 400 Bq/cm[sup 3]. This proportion results in an unusually high indoor radon exposure of the population. The radon source was an 8,700-year-old rock slide of granite gneiss, the largest of the alpine crystalline rocks. It has a strong emanating power because its rocks are heavily fractured and show a slightly increased uranium content. Previous reports show increased lung cancer mortality, myeloid leukemia, kidney cancer, melanoma, and prostate cancer resulting from indoor radon exposure. However, many studies fail to provide accurate information on indoor radon concentrations, classifying them merely as low, intermediate, and high, or they record only minor increases in indoor radon concentrations. Mortality data for 1970-91 were used to calculate age and sex standardized mortality rates (SMR) for 51 sites of carcinoma. The total population of Tyrol were controls. A significantly higher risk was recorded for lung cancer. The high SMR for lung cancer in female subjects is especially striking. Because the numbers were low for the other cancer sites, these were combined in one group to calculate the SMR. No significant increase in SMR was found for this group.

  5. Effectiveness Analysis of Filters Used with Radon Detectors under Extreme Environmental Conditions for Long-term Exposures

    NASA Astrophysics Data System (ADS)

    Moreno, V.; Font, Ll.; Baixeras, C.; Garcia-Orellana, J.; Bach, J.; Grossi, C.; Vargas, A.

    Active and passive radon detectors have been exposed with different filter configurations at the INTE radon chamber controlled conditions. Correction factors and delay times of the radon diffusion through each filter have been determined. Additionally, some of the studied filter/detector configurations have been used to measure radon in several workplaces and outdoor sites under real extreme environmental conditions. Analysis of these detectors showed partial degradation, so used filters seem not to be protective enough for long-term exposures.

  6. Evaluation of Gas-filled Ionization Chamber Method for Radon Measurement at Two Reference Facilities

    SciTech Connect

    Ishikawa, Tetsuo; Tokonami, Shinji; Kobayashi, Yosuke; Sorimachi, Atsuyuki; Yatabe, Yoshinori; Miyahara, Nobuyuki

    2008-08-07

    For quality assurance, gas-filled ionization chamber method was tested at two reference facilities for radon calibration: EML (USA) and PTB (Germany). Consequently, the radon concentrations estimated by the ionization chamber method were in good agreement with the reference radon concentrations provided by EML as well as PTB.

  7. MEASUREMENT AND REPORTING OF RADON EXPOSURES.

    PubMed

    2012-12-01

    Lung cancer risk caused by the inhalation of radon (222Rn) and its short-lived progeny is related to lung dose, which cannot be directly measured. The only measurable parameters which allow the determination of lung doses are the radon and radon progeny activity concentrations and related size distributions. Although lung cancers are caused by the inhaled short-lived radon progeny and not by the radon gas, it is the radon gas which is commonly measured and not its progeny. Since radon gas measurements are much easier to carry out, require less expensive equipment and are especially suited for long-term measurements, the report focuses on the measurement of the radon gas for specific exposure conditions in homes and workplaces. The first objective of this report is to provide information on how to measure radon, covering measurement techniques of radon in air and water, currently available detection systems, and measurement strategies most appropriate for the desired goal of a measurement campaign. Critical measurement strategy decisions are the selection of the measured radionuclide (i.e., radon gas or radon progeny and related size distributions), choice of the measurement period (i.e., short-term or long-term measurements), the choice of detector and its deployment, the type of measurement (i.e., areal or personal measurements), the survey strategy (i.e., integral or time-resolved measurements), or the strategy to accomplish the specific goal of a survey (i.e., measurements describing the current status or retrospective measurements). The choice of a specific strategy depends on the purpose of the survey, and differs therefore between the demands of a nation-wide indoor radon survey or an epidemiological study.The second objective of this report is how to interpret and report the results of these measurements, the associated uncertainties, and the resulting dosimetric estimates. Care should be taken when reporting and interpreting radon measurements because

  8. Overview of radon, lead and asbestos exposure

    SciTech Connect

    Demers, R. )

    1991-11-01

    Reducing the incidence of diseases caused by exposure to radon, lead and asbestos is a major public health challenge. Radon gas, which usually enters a home through the foundation, can cause lung cancer. Exposure to lead through paint, auto emissions and other sources can cause neurologic deficits, as well as anemia, abnormal vitamin D metabolism, nephropathy, hypertension and reproductive abnormalities. Asbestos, which is used in a vast number of products, is primarily associated with parenchymal asbestosis, pleural fibrosis, mesothelioma and lung cancer. The family physician can play a pivotal role in providing information about hazardous exposure, sources of exposure, epidemiology and disease prevention.29 references.

  9. Occupant radon exposure in houses with basements

    SciTech Connect

    Franklin, E.M.; Fuoss, S.

    1995-12-31

    This study compares basement and main-level radon exposure based on bi-level week-long radon measurements, occupancy and activity data collected in normal use during heating and non-heating seasons in a geographically-stratified random sample of about 600 Minnesota homes, in response to critiques of radon measurement protocol. Basement radon (RN1) (M=4.5, SD=4.5) and main level (Rn2)(M=2.9, SD=3.4) correlation was 0.8 (p=.00), including seasonal variation. In a 101-house subsample where Rn1 >=4.0 pCi/L and Rn2 <=3.9 pCi/L, maximum household exposure in basements was 1162 pCiHrs (M=120, Sd=207), main-level 2486 pCiHrs (M-434, SD=421). In same households, persons with most basement-time maxed 100 hrs (M=13,SD=23), persons with most main-level time maxed 160 hrs (M=79, SD=39). Basement activities show two patterns, (1) member used it for personal domain, e.g. sleeping, and (2) household used it for general activities, e.g. TV or children`s play. Basement occupancy justifies measurement of radon in the lowest livable housing level.

  10. 30 CFR 57.5037 - Radon daughter exposure monitoring.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Radon daughter exposure monitoring. 57.5037... Radon daughter exposure monitoring. (a) In all mines at least one sample shall be taken in exhaust mine air by a competent person to determine if concentrations of radon daughters are present. Sampling...

  11. 30 CFR 57.5037 - Radon daughter exposure monitoring.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Radon daughter exposure monitoring. 57.5037... Radon daughter exposure monitoring. (a) In all mines at least one sample shall be taken in exhaust mine air by a competent person to determine if concentrations of radon daughters are present. Sampling...

  12. 30 CFR 57.5037 - Radon daughter exposure monitoring.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Radon daughter exposure monitoring. 57.5037... Radon daughter exposure monitoring. (a) In all mines at least one sample shall be taken in exhaust mine air by a competent person to determine if concentrations of radon daughters are present. Sampling...

  13. 30 CFR 57.5037 - Radon daughter exposure monitoring.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Radon daughter exposure monitoring. 57.5037... Radon daughter exposure monitoring. (a) In all mines at least one sample shall be taken in exhaust mine air by a competent person to determine if concentrations of radon daughters are present. Sampling...

  14. 30 CFR 57.5037 - Radon daughter exposure monitoring.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Radon daughter exposure monitoring. 57.5037... Radon daughter exposure monitoring. (a) In all mines at least one sample shall be taken in exhaust mine air by a competent person to determine if concentrations of radon daughters are present. Sampling...

  15. EVALUATION OF RADON EMANATION FROM SOIL WITH VARYING MOISTURE CONTENT IN A SOIL CHAMBER

    EPA Science Inventory

    The paper describes measurements to quantitatively identify the extent to which moisture affects radon emanation and diffusive transport components of a sandy soil radon concentration gradient obtained in the EPA test chamber. The chamber (2X2X4 m long) was constructed to study t...

  16. EVALUATION OF RADON EMANATION FROM SOIL WITH VARYING MOISTURE CONTENT IN A SOIL CHAMBER

    EPA Science Inventory

    The paper describes measurements to quantitatively identify the extent to which moisture affects radon emanation and diffusive transport components of a sandy soil radon concentration gradient obtained in the EPA test chamber. The chamber (2X2X4 m long) was constructed to study t...

  17. The Distribution of Exposure to Radon: Effects of Population Mobility

    SciTech Connect

    Gadgil, A.J.; Rein, S.; Nero, A.V.; Wollenberg Jr., H.A.

    1993-01-01

    The distribution of population exposures to radon, rather than the distribution of indoor radon concentrations, determines the fraction of population exposed to exceptionally high risk from radon exposures. Since this fraction at high risk has prompted the development of public policies on radon, it is important to first determine the magnitude of this fraction, and then how it much would decrease with different implementation program options for radon mitigation. This papers presents an approach to determining the distribution of population exposures to radon from public domain data, and illustrates it with application to the state of Minnesota. During this work, we are led to define a radon entry potential index which appears useful in the search for regions with high radon houses.

  18. Assessing the risks from exposure to radon in dwellings

    SciTech Connect

    Walsh, P.J.; Lowder, W.M.

    1983-07-01

    The factors used to assess the radiation dose and health risks from human exposure to radon in dwellings are critically reviewed in this summary. Sources of indoor radon and determinants of air concentrations and exposure levels are given as well as the uncertainties that exist in their formulation. Methods of assessing health effects from inhalation of radon and its progeny are discussed with emphasis on dosimetry of radon daughters and formulation of risk per dose values. Finally, methods of assessing risks for general population exposures to indoor radon concentrations are treated.

  19. Measurements of indoor radon concentrations and assessment of radiation exposure

    NASA Astrophysics Data System (ADS)

    Medici, F.; Rybach, L.

    1994-02-01

    In the past decade many international studies have established that the radioactive gas radon is responsible to a large extent for the radiation dose absorbed by the population. Consequently the Swiss Federal Health Office started and sponsored a research program called RAPROS (Radon Programm Schweiz, 1987-1991) to assess the relevant aspects of radon exposure in Switzerland. The average indoor radon concentration in Swiss living rooms is about 60-70 Bq m -3, this corresponds to an annual dose of about 2.2 mSv, but values largely exceeding 1000 Bq m -3 were also found. Often very strong temporal fluctuations of indoor radon concentrations were measured. The ground directly underneath buildings is the main radon source of indoor radon. The material properties that influence the radon production and transport in soils are: radium content, emanating coefficient and soil gas permeability; among them only the last one can vary over many orders of magnitude. The permeability is consequently the decisive factor that enables radon transport in the subsurface. To characterize the radon potential of soils a radon availability index ( RAV) was introduced. Our investigations have also shown that in karst systems the radon concentration in the air is often increased to 10-100 times higher than in buildings. This radon-charged air is able to travel over considerable distances through faults and cavities in the underground and reach living rooms built over karstified areas.

  20. Avian inhalation exposure chamber

    DOEpatents

    Briant, J.K.; Driver, C.J.

    1992-05-05

    An exposure system is designed for delivering gaseous material ranging in particle size from 0.4 micrometers to 20.0 micrometers uniformly to the heads of experimental animals, primarily birds. The system includes a vertical outer cylinder and a central chimney with animal holding bottles connected to exposure ports on the vertical outer cylinder. 2 figs.

  1. Avian inhalation exposure chamber

    DOEpatents

    Briant, James K.; Driver, Crystal J.

    1992-01-01

    An exposure system for delivering gaseous material ranging in particle size from 0.4 micrometers to 20.0 micrometers uniformly to the heads of experimental animals, primarily birds. The system includes a vertical outer cylinder and a central chimney with animal holding bottles connected to exposure ports on the vertical outer cylinder.

  2. Assessing exposure to granite countertops--Part 2: Radon.

    PubMed

    Allen, Joseph G; Minegishi, Taeko; Myatt, Theodore A; Stewart, James H; McCarthy, John F; Macintosh, David L

    2010-05-01

    Radon gas ((222)Rn) is a natural constituent of the environment and a risk factor for lung cancer that we are exposed to as a result of radioactive decay of radium ((226)Ra) in stone and soil. Granite countertops, in particular, have received recent media attention regarding their potential to emit radon. Radon flux was measured on 39 full slabs of granite from 27 different varieties to evaluate the potential for exposure and examine determinants of radon flux. Flux was measured at up to six pre-selected locations on each slab and also at areas identified as potentially enriched after a full-slab scan using a Geiger-Muller detector. Predicted indoor radon concentrations were estimated from the measured radon flux using the CONTAM indoor air quality model. Whole-slab average emissions ranged from less than limit of detection to 79.4 Bq/m(2)/h (median 3.9 Bq/m(2)/h), similar to the range reported in the literature for convenience samples of small granite pieces. Modeled indoor radon concentrations were less than the average outdoor radon concentration (14.8 Bq/m(3); 0.4 pCi/l) and average indoor radon concentrations (48 Bq/m(3); 1.3 pCi/l) found in the United States. Significant within-slab variability was observed for stones on the higher end of whole slab radon emissions, underscoring the limitations of drawing conclusions from discrete samples.

  3. Measuring radon exhalation rate in two cycles avoiding the effects of back-diffusion and chamber leakage.

    PubMed

    Tan, Yanliang; Xiao, Detao

    2013-10-01

    This paper will present a simple method for measuring the radon exhalation rate from the medium surface in two cycles and also avoiding the effects of back-diffusion and chamber leakage. The method is based on a combination of the "accumulation chamber" technique and a radon monitor. The radon monitor performs the measurement of the radon concentration inside the accumulation chamber, and then the radon exhalation rate can be obtained by simple calculation. For reducing the systematic error and the statistical uncertainty, too short of total measurement time is not appropriate, and the first cycle time should be about 70 % of the total measurement. The radon exhalation rate from the medium surface obtained through this method is in good agreement with the reference value. This simple method can be applied to develop and improve the instruments for measuring radon exhalation rate.

  4. Residential Radon Exposure and Risk of Lung Cancer in Missouri

    Cancer.gov

    A case-control study of lung cancer and residential radon exposure in which investigators carried out both standard year-long air measurements and CR-39 alpha detector measurements (call surface monitors)

  5. Open charcoal chamber method for mass measurements of radon exhalation rate from soil surface.

    PubMed

    Tsapalov, Andrey; Kovler, Konstantin; Miklyaev, Peter

    2016-08-01

    Radon exhalation rate from the soil surface can serve as an important criterion in the evaluation of radon hazard of the land. Recently published international standard ISO 11665-7 (2012) is based on the accumulation of radon gas in a closed container. At the same time since 1998 in Russia, as a part of engineering and environmental studies for the construction, radon flux measurements are made using an open charcoal chamber for a sampling duration of 3-5 h. This method has a well-defined metrological justification and was tested in both favorable and unfavorable conditions. The article describes the characteristics of the method, as well as the means of sampling and measurement of the activity of radon absorbed. The results of the metrological study suggest that regardless of the sampling conditions (weather, the mechanism and rate of radon transport in the soil, soil properties and conditions), uncertainty of method does not exceed 20%, while the combined standard uncertainty of radon exhalation rate measured from the soil surface does not exceed 30%. The results of the daily measurements of radon exhalation rate from the soil surface at the experimental site during one year are reported. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Residential radon-222 exposure and lung cancer: exposure assessment methodology.

    PubMed

    Field, R W; Steck, D J; Lynch, C F; Brus, C P; Neuberger, J S; Kross, B C

    1996-01-01

    Although occupational epidemiological studies and animal experimentation provide strong evidence that radon-222 (222Rn) progeny exposure causes lung cancer, residential epidemiological studies have not confirmed this association. Past residential epidemiological studies have yielded contradictory findings. Exposure misclassification has seriously compromised the ability of these studies to detect whether an association exists between 222Rn exposure and lung cancer. Misclassification of 222Rn exposure has arisen primarily from: 1) detector measurement error; 2) failure to consider temporal and spatial 222Rn variations within a home; 3) missing data from previously occupied homes that currently are inaccessible; 4) failure to link 222Rn concentrations with subject mobility; and 5) measuring 222Rn gas concentration as a surrogate for 222Rn progeny exposure. This paper examines these methodological dosimetry problems and addresses how we are accounting for them in an ongoing, population-based, case-control study of 222Rn and lung cancer in Iowa.

  7. Doses to LiF :Ti, Mg chips encapsulated in plastic extremity rings as a result of radon gas exposure.

    PubMed

    Kearfott, Kimberlee J; Noon, Evan P; Rafique, Muhammad

    2015-06-01

    Previous studies measured the effects of (222)Rn on various thermoluminescent dosemeters (TLDs). This study quantified the effects of (222)Rn on LiF : Ti,Mg chips encapsulated in plastic extremity rings. For 28 d, one batch of TLDs was left in a chamber with high radon levels, and another batch in a control chamber with normal background radon levels. A few TLDs in each batch were removed from the rings for direct exposure to the ambient air in each chamber. Passive continuous radon monitors (CRMs) recorded the (222)Rn levels. TLDs were processed using a third-party dosimetry company, CRM data were analysed, and the relationship between integrated (222)Rn concentration and TLD response was determined. The batch of TLDs in the experimental chamber showed a weak response to (222)Rn gas, which was in the order of 0.5 nSv Bq(-1) m(3) d(-1).

  8. Electret ion chamber radon monitors measure dissolved 222Rn in water.

    PubMed

    Kotrappa, P; Jester, W A

    1993-04-01

    This paper describes a simple and relatively inexpensive method of determining the concentration of dissolved 222Rn in water. The method involves a recently developed electret-passive environmental radon monitor, which uses an electret ion chamber. The procedure consists of sealing a known volume of a carefully collected water sample with one of these monitors in an exposure container and determining the average equilibrium 222Rn gas concentration in the air phase during the exposure time period. This average concentration can then be used to calculate the 222Rn concentration in the original water sample. Identical samples were analyzed both by this new method and by a standard liquid scintillation method, and the results were compared over a wide range of 222Rn concentrations. There was good agreement except that the electret ion chamber method gave results that were consistently lower by about 15%. This bias in the results was attributed to both 222Rn losses during sample handling and possibly to some errors in the assumptions made in the theoretical model. A correction factor is recommended to bring the results of this technique into agreement with the standard method. The procedures are simple and economical and can be easily employed by many primary 222Rn-measuring laboratories currently using these monitors for measuring indoor 222Rn.

  9. NRC committee provides new risk estimates for exposure to radon

    SciTech Connect

    Not Available

    1988-03-01

    A new set of age-specific estimates describing the increased risk of lung cancer following exposure to radon was released in January by a National Research Council committee. The revised estimates result from new statistical techniques used to analyze previously collected data. In a study jointly sponsored by the Environmental Protection Agency (EPA) and the Nuclear Regulatory Commission, the committee concluded that lifetime exposure to one working level month (WLM) of radon per year, a standard measure used by radiation experts, increases an individual's chances of dying from lung cancer by 1.5 times compared with someone exposed only to background levels of radon. The committee estimated that, for every 1 million people exposed over a lifetime to one WLM of radon, about 350 additional deaths would occur due to lung cancer. The committee found that lung cancer risks associated with radon increased with increasing length of exposure. Moreover, it said that 15 years after exposure to radon has ended, the risk of lung cancer from the exposure declines to half the original risk.

  10. Cancer risks from exposure to radon in homes.

    PubMed Central

    Axelson, O

    1995-01-01

    Exposure to radon and its decay products in mines is a well recognized risk of lung cancer in miners. A large number of epidemiologic studies from various countries are quite consistent in this respect even it the magnitude of the risk differs according to exposure levels. Indoor radon became a concern in the 1970s and about a dozen studies have been conducted since 1979, mainly of the case-control design. From first being of a simple pilot character, the designs have become increasingly sophisticated, especially with regard to exposure assessment. Crude exposure estimates based on type of house, building material and geological features have been supplemented or replaced by quite extensive measurements. Still, exposure assessment remains a difficult and uncertain issue in these studies, most of which indicate a lung cancer risk from indoor radon. Also a recent large scale study has confirmed a lung cancer risk from indoor radon. More recently there are also some studies, mainly of the correlation type, suggesting other cancers also to be related to indoor radon, especially leukemia, kidney cancer, and malignant melanoma, and some other cancers as well. The data are less consistent and much more uncertain than for indoor radon and lung cancer, however; and there is no clear support from studies of miners in this respect. PMID:7614945

  11. A diffusion chamber for passive separated measurements of radon/thoron concentration in dwellings

    NASA Astrophysics Data System (ADS)

    Torabi Nabil, F.; Hosseini Pooya, S. M.; Shamsaie Zafarghandi, M.; Taheri, M.

    2012-12-01

    In this research, a passive diffusion chamber has been developed for separated measurement of radon and thoron. The chamber consists of two volumes which are separated by a fiber glass filter. Two lexan polycarbonate nuclear track detectors (film) are placed inside of the volumes to detect the alpha particles of radon/thorn and/or their progenies. Another lexan polycarbonate detector covered with an optimized thickness of an attenuator is placed outside of the chamber to measure only 212Po which its concentration can be related to that of long-life thoron progeny, 212Pb. The sensitivities have been measured by 2.06 and 0.053 [tracks cm-2(kBq m-3 day)-1] values for radon and thoron respectively inside of the chamber, and 7960 [tracks cm-2(kBq m-3 day)-1] value for thoron outside of the chamber. So the system can be successfully used for separated measurement of an extended range of radon/thoron concentrations in dwellings.

  12. Residential radon exposure and lung cancer in Sweden

    SciTech Connect

    Pershagen, G.; Akerblom, G.; Axelson, O.; Clavensjoe, B.D.; Damber, L.; Desai, G.; Enflo, A.; Lagarde, F.; Mellander, H.; Svartengren, M. )

    1994-01-20

    BACKGROUND. Residential radon is the principal source of exposure to ionizing radiation in most countries. To determine the implications for the risk of lung cancer, we performed a nationwide case-control study in Sweden. METHODS. The study included 586 women and 774 men 35 to 74 years of age with lung cancer that was diagnosed between 1980 and 1984. For comparison, 1380 female and 1467 male controls were studied. Radon was measured in 8992 dwellings occupied by the study subjects at some time since 1947. Information on smoking habits and other risk factors for lung cancer was obtained from questionnaires. RESULTS. Radon levels followed a log-normal distribution, with geometric and arithmetic means of 1.6 and 2.9 pCi per liter (60.5 and 106.5 Bq per cubic meter), respectively. The risk of lung cancer increased in relation to both estimated cumulative and time-weighted exposure to radon. In comparison with time-weighted average radon concentrations up to 1.4 pCi per liter (50 Bq per cubic meter), the relative risk was 1.3 (95 percent confidence interval, 1.1 to 1.6) for average radon concentrations of 3.8 to 10.8 pCi per liter (140 to 400 Bq per cubic meter), and it was 1.8 (95 percent confidence interval, 1.1 to 2.9) at concentrations exceeding 10.8 pCi per liter. The estimates of risk were in the same range as those projected from data in miners. The interaction between radon exposure and smoking with regard to lung cancer exceeded additivity and was closer to a multiplicative effect. CONCLUSIONS. Residential exposure to radon is an important cause of lung cancer in the general population. The risks appear consistent with earlier estimates based on data in miners.

  13. Radon detection in conical diffusion chambers: Monte Carlo calculations and experiment

    SciTech Connect

    Rickards, J.; Golzarri, J. I.; Espinosa, G.; Vázquez-López, C.

    2015-07-23

    The operation of radon detection diffusion chambers of truncated conical shape was studied using Monte Carlo calculations. The efficiency was studied for alpha particles generated randomly in the volume of the chamber, and progeny generated randomly on the interior surface, which reach track detectors placed in different positions within the chamber. Incidence angular distributions, incidence energy spectra and path length distributions are calculated. Cases studied include different positions of the detector within the chamber, varying atmospheric pressure, and introducing a cutoff incidence angle and energy.

  14. 'Radon Concentration Survey in Inner Rooms from Deputy Chamber and National Congress-Brasilia/DF'

    SciTech Connect

    Nicoli, Ieda Gomes; Cardozo, Katia Maria; Azevedo Gouvea, Vandir de

    2008-08-07

    Radon gas has been monitored in many environments such as rural and urban houses, high natural radioactivity areas and underground mining regions. Nevertheless few data are reported in literature about studies in state buildings. So we get in touch with these buildings managers, where work the Deputy Chamber and the National Congress in Brasilia--DF, in order to obtain radon data in these state buildings, so representative for brazilian people. In order to make a preliminary scanning of radon concentration in these buildings, it was put in selected points, radon nuclear track passive detectors type SSNTD, specifically polycarbonate Lexan, which were exposed for periods from two to five months. Afterwards they were sent to Nuclear Engineering Institute in Rio de Janeiro for analysis of {sup 222}Rn contents. Derived values, whose average value was about 73 Bq/m{sup 3}, were all under maximum permissible limits for radon 200 Bq/m{sup 3}, established by International Comission on Radiological Protection--ICRP 65, for inner environments of houses and state buildings. This work has been coordinated by CNEN Office in Braselia with effective participation of Nuclear Engineering Institute from CNEN--RJ, that has worked since beginning of april 2004, supplying and analysing radon detectors.

  15. Radon levels in Romanian caves: an occupational exposure survey.

    PubMed

    Cucoş Dinu, Alexandra; Călugăr, Monica I; Burghele, Bety D; Dumitru, Oana A; Cosma, Constantin; Onac, Bogdan P

    2016-10-01

    A comprehensive radon survey has been carried out in seven caves located in the western half of Romania's most significant karst regions. Touristic and non-touristic caves were investigated with the aim to provide a reliable distribution of their radon levels and evaluate the occupational exposure and associated effective doses. Radon gas concentrations were measured with long-term diffusion-type detectors during two consecutive seasons (warm and cold). All investigated caves exceed the European Union reference level of radon gas at workplaces (300 Bq/m(3)). The radon concentration in these caves ranges between 53 and 2866 Bq/m(3), reflecting particular cave topography, season-related cave ventilation, and complex tectonic and geological settings surrounding each location. Relatively homogeneous high radon levels occur in all investigated touristic caves and in Tăuşoare and Vântului along their main galleries. Except for Muierii, in all the other caves radon levels are higher during the warm season, compared to the cold one. This suggests that natural cave ventilation largely controls the underground accumulation of radon. The results reported here reveal that the occupational exposure in Urşilor, Vadu Crişului, Tăuşoare, Vântului, and Muierii caves needs to be carefully monitored. The effective doses to workers vary between an average of 0.25 and 4.39 mSv/year depending on the measuring season. The highest values were recorded in show caves, ranging from 1.15 to 6.15 mSv/year, well above the European recommended limit, thus posing a potential health hazard upon cave guides, cavers, and scientists.

  16. Children's Exposure to Radon in Nursery and Primary Schools.

    PubMed

    Branco, Pedro T B S; Nunes, Rafael A O; Alvim-Ferraz, Maria C M; Martins, Fernando G; Sousa, Sofia I V

    2016-03-30

    The literature proves an evident association between indoor radon exposure and lung cancer, even at low doses. This study brings a new approach to the study of children's exposure to radon by aiming to evaluate exposure to indoor radon concentrations in nursery and primary schools from two districts in Portugal (Porto and Bragança), considering different influencing factors (occupation patterns, classroom floor level, year of the buildings' construction and soil composition of the building site), as well as the comparison with IAQ standard values for health protection. Fifteen nursery and primary schools in the Porto and Bragança districts were considered: five nursery schools for infants and twelve for pre-schoolers (seven different buildings), as well as eight primary schools. Radon measurements were performed continuously. The measured concentrations depended on the building occupation, classroom floor level and year of the buildings' construction. Although they were in general within the Portuguese legislation for IAQ, exceedances to international standards were found. These results point out the need of assessing indoor radon concentrations not only in primary schools, but also in nursery schools, never performed in Portugal before this study. It is important to extend the study to other microenvironments like homes, and in time to estimate the annual effective dose and to assess lifetime health risks.

  17. Determination of radon exhalation from construction materials using VOC emission test chambers.

    PubMed

    Richter, M; Jann, O; Kemski, J; Schneider, U; Krocker, C; Hoffmann, B

    2013-10-01

    The inhalation of (222) Rn (radon) decay products is one of the most important reasons for lung cancer after smoking. Stony building materials are an important source of indoor radon. This article describes the determination of the exhalation rate of stony construction materials by the use of commercially available measuring devices in combination with VOC emission test chambers. Five materials - two types of clay brick, clinker brick, light-weight concrete brick, and honeycomb brick - generally used for wall constructions were used for the experiments. Their contribution to real room concentrations was estimated by applying room model parameters given in ISO 16000-9, RP 112, and AgBB. This knowledge can be relevant, if for instance indoor radon concentration is limited by law. The test set-up used here is well suited for application in test laboratories dealing with VOC emission testing.

  18. The Effects of Radon Exposure on Physical and Psychological Health

    DTIC Science & Technology

    1991-08-15

    Science of the Total Environment , 45. 459-46. Guimond, R. j...of natural radiation in France. The Science of the Total Environment . 45, 467-474. Roessler, C. E. , Roessler, G. S., & Bolch, W. E. (1983...Results from a survey of indoor radon exposures in the Federal Republic of Germany. The Science of the Total Environment . 45, 307-310.

  19. Application of thoron interference as a tool for simultaneous measurement of radon and thoron with a pulse ionisation chamber.

    PubMed

    Tripathi, R M; Sumesh, C G; Vinod Kumar, A; Puranik, V D

    2013-07-01

    Pulse ionisation chamber (PIC)-based monitors measuring radioactive gas radon ((222)Rn) without energy discrimination will have interference due to thoron ((220)Rn) present in the atmosphere. A technique has been developed to use this property of interference for simultaneous measurement of radon and thoron gas. These monitors work on the principle of counting of gross alphas emitted from radon and its progeny. A theoretical model has been developed for the variation of thoron sensitivity with respect to the flow rate of gas through the monitor. The thoron sensitivity of the monitor is found to vary with the flow rate of gas through the monitor. Using this sensitivity, the sampling procedure has been developed and verified for simultaneous measurement of radon and thoron. The PIC-measured radon and thoron concentration using this procedure agrees well with those measured by using standard radon and thoron discriminating monitor.

  20. The Italian national survey of indoor radon exposure.

    PubMed

    Sciocchetti, G; Scacco, F; Baldassini, P G; Battella, C; Bovi, M; Monte, L

    1985-10-01

    An investigation is being developed by the Comitato Nazionale per la Ricerca e per lo Sviluppo dell'Energia Nucleare e delle Energie Alternative, ENEA, to assess the indoor exposure of the Italian population. The programme, which started in 1982, includes regional and local surveys in all the administrative districts and intensive investigations of factors which influence indoor radon levels. The survey is organized by statistical areas of sampling to obtain representative samples of houses. The definition of the areas takes into account basic parameters e.g. geolithological environments, radon soil gas from underlying soils and rocks, specific activities of local building materials, climatic and seasonal variations, building technology, types of houses and town planning. The collected data may also be used for the compilation of radon risk maps to plan special monitoring and remedial actions if needed. Preliminary results concerning the above items are discussed.

  1. Radon

    MedlinePlus

    ... Risks . Accessed August 19, 2016. U.S. EPA. Indoor Air Quality. What about Radon and Radioactivity in Granite Countertops ? Accessed August 19, 2016 U.S. EPA. Indoor Air Quality. A Citizen's Guide to Radon . Accessed August 19, ...

  2. Radon

    MedlinePlus

    ... move to air, groundwater, and surface water. Radon-222 has a radioactive half-life of about 4 ... The main isotope of health concern is radon-222 ( 222 Rn). Many scientists believe that the alpha ...

  3. Development of cataract and corneal opacity in mice due to radon exposure

    NASA Astrophysics Data System (ADS)

    Abdelkawi, S. A.; Abo-Elmagd, M.; Soliman, H. A.

    This work investigates the radiation damage on the eye of albino mice exposed to effective radon doses ranging from 20.92 to 83.68 mSv. These doses were taken over 2-8 weeks using a radon chamber constructed by the National Institute for Standard (Egypt). The guidance on the quality assurance program for radon measurements was followed. Therefore, the estimated doses received by the laboratory animals meet the requirements of national standardE The refractive index(RI) and protein concentration were measured for soluble proteins of both corneas and lenses. In addition, the sodium dodecyle sulfate polyacrylamide gel electrophoresis (SDSPAGE) technique was used. The results show increasing of the RI of both cornea and lens proteins and decreasing in total protein concentration of exposed animals. These results were accompanied with changes in the SDSPAGE profile for both cornea and lens. Therefore, radon exposure produces substantial hazards to the cornea and lens of experimental animals and has a crucial role in the development of cataract and corneal opacity.

  4. Indoor air: Radon exposure. (Latest citations from Pollution Abstracts). Published Search

    SciTech Connect

    Not Available

    1993-05-01

    The bibliography contains citations concerning indoor exposure to radon and its control. Articles address radon levels in homes, schools, and occupational sites. Sources of radon discussed include soils, rock strata, building materials, water supplies, combustion sources, and tobacco smoke. Risk assessment studies, toxicity, and control of radon exposure are also addressed as related topics. (Contains a minimum of 205 citations and includes a subject term index and title list.)

  5. Radon exposure and tumors of the central nervous system.

    PubMed

    Ruano-Ravina, Alberto; Dacosta-Urbieta, Ana; Barros-Dios, Juan Miguel; Kelsey, Karl T

    2017-03-15

    To review the published evidence of links between radon exposure and central nervous system tumors through a systematic review of the scientific literature. We performed a thorough bibliographic search in Medline (PubMed) and EMBASE. We combined MeSH (Medical Subject Heading) terms and free text. We developed a purpose-designed scale to assess the quality of the included manuscripts. We have included 18 studies, 8 performed on miners, 3 on the general population and 7 on children, and the results have been structured using this classification. The results are inconclusive. An association between radon exposure and central nervous system tumors has been observed in some studies on miners, but not in others. The results observed in the general adult population and in children are also mixed, with some research evincing a statistically significant association and others showing no effect. We cannot conclude that there is a relationship between radon exposure and central nervous system tumors. The available studies are extremely heterogeneous in terms of design and populations studied. Further research is needed in this topic, particularly in the general population residing in areas with high levels of radon. Copyright © 2017 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.

  6. Radon

    MedlinePlus

    ... comes from the natural breakdown of uranium in soil, rock, and water. Radon is the second leading cause of lung cancer in the United States. There are low levels of radon outdoors. Indoors, there can be high levels. Radon can enter ...

  7. Exposure to radon and radon progeny in the indoor environment. Final report

    SciTech Connect

    Socolow, R.H.

    1994-10-01

    This report discusses the work done by the Center for Energy and Environmental Studies at Princeton University as part of the radon research program. It involves radon measurements in various buildings, as well as the use of natural ventilation to mitigate radon levels. The report is divided into four chapters: The use of radon entry rate measurements to understand radon concentration in buildings; Use of natural basement ventilation to control radon in single family dwellings; The effect of natural ventilation on radon and radon progeny levels in houses; and Comparison of natural and forced ventilation for radon mitigation in houses.

  8. The Concept of Equivalent Radon Concentration for Practical Consideration of Indoor Exposure to Thoron

    PubMed Central

    Chen, Jing; Moir, Deborah

    2012-01-01

    To consider the total exposure to indoor radon and thoron, a concept of equivalent radon concentration for thoron is introduced, defined as the radon concentration that delivers the same annual effective dose as that resulting from the thoron concentration. The total indoor exposure to radon and thoron is then the sum of the radon concentration and the equivalent radon concentration for thoron. The total exposure should be compared to the radon guideline value, and if it exceeds the guideline value, appropriate remedial action is required. With this concept, a separate guideline for indoor thoron exposure is not necessary. For homes already tested for radon with radon detectors, Health Canada’s recommendation of a 3-month radon test performed during the fall/winter heating season not only ensures a conservative estimate of the annual average radon concentration but also covers well any potentially missing contribution from thoron exposure. In addition, because the thoron concentration is much lower than the radon concentration in most homes in Canada, there is no real need to re-test homes for thoron. PMID:22470292

  9. The concept of equivalent radon concentration for practical consideration of indoor exposure to thoron.

    PubMed

    Chen, Jing; Moir, Deborah

    2012-01-01

    To consider the total exposure to indoor radon and thoron, a concept of equivalent radon concentration for thoron is introduced, defined as the radon concentration that delivers the same annual effective dose as that resulting from the thoron concentration. The total indoor exposure to radon and thoron is then the sum of the radon concentration and the equivalent radon concentration for thoron. The total exposure should be compared to the radon guideline value, and if it exceeds the guideline value, appropriate remedial action is required. With this concept, a separate guideline for indoor thoron exposure is not necessary. For homes already tested for radon with radon detectors, Health Canada's recommendation of a 3-month radon test performed during the fall/winter heating season not only ensures a conservative estimate of the annual average radon concentration but also covers well any potentially missing contribution from thoron exposure. In addition, because the thoron concentration is much lower than the radon concentration in most homes in Canada, there is no real need to re-test homes for thoron.

  10. An atmospheric exposure chamber for small animals

    NASA Technical Reports Server (NTRS)

    Glaser, R. M.; Weiss, H. S.; Pitt, J. F.; Grimard, M.

    1982-01-01

    The purpose of this project was to design a long-term environmental exposure chamber for small animals. This chamber is capable of producing hypoxic, normoxic and hyperoxic atmospheres which are closely regulated. The chamber, which is of the recycling type, is fashioned after clear plastic germ-free isolators. Oxygen concentration is set and controlled by a paramagnetic O2 analyzer and a 3-way solenoid valve. In this way either O2 or N2 may be provided to the system by way of negative O2 feedback. Relative humidity is maintained at 40-50 percent by a refrigeration type dryer. Carbon dioxide is absorbed by indicating soda lime. A diaphragm pump continuously circulates chamber gas at a high enough flow rate to prevent buildup of CO2 and humidity. This chamber has been used for numerous studies which involve prolonged exposure of small animals to various O2 concentrations.

  11. An atmospheric exposure chamber for small animals

    NASA Technical Reports Server (NTRS)

    Glaser, R. M.; Weiss, H. S.; Pitt, J. F.; Grimard, M.

    1982-01-01

    The purpose of this project was to design a long-term environmental exposure chamber for small animals. This chamber is capable of producing hypoxic, normoxic and hyperoxic atmospheres which are closely regulated. The chamber, which is of the recycling type, is fashioned after clear plastic germ-free isolators. Oxygen concentration is set and controlled by a paramagnetic O2 analyzer and a 3-way solenoid valve. In this way either O2 or N2 may be provided to the system by way of negative O2 feedback. Relative humidity is maintained at 40-50 percent by a refrigeration type dryer. Carbon dioxide is absorbed by indicating soda lime. A diaphragm pump continuously circulates chamber gas at a high enough flow rate to prevent buildup of CO2 and humidity. This chamber has been used for numerous studies which involve prolonged exposure of small animals to various O2 concentrations.

  12. Radon exposure of the skin: I. Biological effects.

    PubMed

    Charles, M W

    2007-09-01

    Radon progeny can plate out on skin and give rise to exposure of the superficial epidermis from alpha emitters Po-218 (7.7 MeV, range approximately 66 microm) and Po-214 (6 MeV, range approximately 44 microm). Dose rates from beta/gamma emitters Pb-214 and Bi-214 are low and only predominate at depths in excess of the alpha range. This paper reviews the evidence for a causal link between exposure from radon and its progeny, and deterministic and stochastic biological effects in human skin. Radiation induced skin effects such as ulceration and dermal atrophy, which require irradiation of the dermis, are ruled out for alpha irradiation from radon progeny because the target cells are considerably deeper than the range of alpha particles. They have not been observed in man or animals. Effects such as erythema and acute epidermal necrosis have been observed in a few cases of very high dose alpha particle exposures in man and after acute high dose exposure in animals from low energy beta radiations with similar depth doses to radon progeny. The required skin surface absorbed doses are in excess of 100 Gy. Such effects would require extremely high levels of radon progeny. They would involve quite exceptional circumstances, way outside the normal range of radon exposures in man. There is no definitive identification of the target cells for skin cancer induction in animals or man. The stem cells in the basal layer which maintain the epidermis are the most plausible contenders for target cells. The majority of these cells are near the end of the range of radon progeny alpha particles, even on the thinnest body sites. The nominal depth of these cells, as recommended by the International Commission on Radiological Protection (ICRP), is 70 microm. There is evidence however that some irradiation of the hair follicles and/or the deeper dermis, as well as the inter-follicular epidermis, is also necessary for skin cancer induction. Alpha irradiation of rodent skin that is

  13. Residential Radon Exposure and Lung Cancer: Evidence of an Inverse Association in Washington State.

    ERIC Educational Resources Information Center

    Neuberger, John S.; And Others

    1992-01-01

    Presents results of a descriptive study of lung cancer death rates compared to county levels of radon in Washington State. Age-specific death rates were computed for white female smokers according to radon exposure. A significant lung cancer excess was found in lowest radon counties. No significant difference was found between the proportion of…

  14. Residential Radon Exposure and Lung Cancer: Evidence of an Inverse Association in Washington State.

    ERIC Educational Resources Information Center

    Neuberger, John S.; And Others

    1992-01-01

    Presents results of a descriptive study of lung cancer death rates compared to county levels of radon in Washington State. Age-specific death rates were computed for white female smokers according to radon exposure. A significant lung cancer excess was found in lowest radon counties. No significant difference was found between the proportion of…

  15. On the calibration of a radon exhalation monitor based on the electrostatic collection method and accumulation chamber.

    PubMed

    Tan, Yanliang; Tokonami, Shinji; Hosoda, Masahiro

    2015-06-01

    The radon exhalation rate can be obtained quickly and easily from the evolution of radon concentration over time in the accumulation chamber. Radon monitoring based on the electrostatic collection method is not interfered with by (220)Rn. In this paper, we propose that the difference between radon and (218)Po concentrations in the measurement cell of this kind of radon exhalation monitor is the main system error, and it changes with time and different effective decay constants. Based on the results of simulation experiments, we propose that the calibration factor obtained from the suitable experiment cannot completely correct the system error, even if it is useful to reduce the measurement error. The better way for reducing measurement error is to use the new measurement model which we have proposed in recent years.

  16. Residential radon exposure and lung cancer: risk in nonsmokers.

    PubMed

    Neuberger, John S; Gesell, Thomas F

    2002-07-01

    Lung cancer is a disease that is almost entirely caused by smoking; hence, it is almost totally preventable. Yet there are a small percentage of cases, perhaps as many as 5 to 15%, where there are other causes. Risk factors identified for this other group include passive smoking, occupational exposure to certain chemicals and ionizing radiation, diet, and family history of cancer. In the United States cigarette smoking is on the decline among adults, occupational exposures are being reduced, and people are being made more aware of appropriate diets. These changes are gradually resulting in a reduced risk for this disease. Lung cancer in the U.S. may, therefore, eventually become largely a disease of the past. It remains important, however, to continue to study the cause(s) of lung cancer in non-smokers, particularly never smokers. Because of our interest in the effects of residential radon exposure on the development of lung cancer in non-smokers, we conducted a critical review of the scientific literature to evaluate this issue in detail. Strict criteria were utilized in selecting studies, which included being published in a peer reviewed journal, including non-smokers in the studied populations, having at least 100 cases, and being of case-control design. A total of 12 individual studies were found that met the criteria, with 10 providing some information on non-smokers. Most of these studies did not find any significant association between radon and lung cancer in non-smokers. Furthermore, data were not presented in sufficient detail for non-smokers in a number of studies. Based on the most recent findings, there is some evidence that radon may contribute to lung cancer risk in current smokers in high residential radon environments. The situation regarding the risk of lung cancer from radon in non-smokers (ex and never) is unclear, possibly because of both the relatively limited sample size of non-smokers and methodological limitations in most of the individual

  17. The exposure of United Kingdom miners to radon

    PubMed Central

    Duggan, M. J.; Soilleux, P. J.; Strong, J. C.; Howell, D. M.

    1970-01-01

    Duggan, M.J., Soilleux, P.J., Strong, J.C., and Howell, D.M. (1970).Brit. J. industr. Med.,27, 106-109. The exposure of United Kingdom miners to radon. Airborne radon has been recognized as a probable cause of lung cancer since the epidemiological studies made in the mining communities of Schneeberg and Jachymov during the 1920s and 1930s. Uranium miners are generally exposed to high concentrations of radon, and the growth of the uranium mining industry in the past 20 years has therefore stimulated a great amount of work on the risk from inhalation of radon and its daughters. However, there is still no general agreement on either the physical measurements in which the maximum permissible concentration in air should be expressed or the numerical value of this concentration. There are no uranium mines being worked in the United Kingdom but there are considerable numbers of coal and other mines. It was therefore decided to make some radon measurements in a selection of mines in the UK to see if there was any prospect of obtaining useful dose-risk data. Measurements were made in 22 mines in all - 12 coal mines and 10 other mines - and the highest concentrations were found in three haematite mines in West Cumberland and in the two tin mines which were visited. The concentrations in these five mines were, in general, greater than 0·3 of a working level (WL) and in many locations were greater than 1 WL. Because of these findings and also because an excess incidence of lung cancer among West Cumberland haematite miners has been previously reported, a further study of the mortality experience of West Cumberland miners has been carried out by Boyd, Doll, Faulds, and Leiper (1970). Their findings are reported in this Journal (p. 97). PMID:5428629

  18. Electret ion chamber-based passive radon-thoron discriminative monitors.

    PubMed

    Kotrappa, P; Steck, D

    2010-10-01

    Electret ion chambers (EICs), commercially available under brand name E-PERM(®), are widely used for measuring indoor and outdoor (222)Rn concentrations in air. These are designed to respond only to (222)Rn and not to (220)Rn by restricting diffusional entry area. Such radon EIC (R EIC) monitors are modified by increasing the entry area to allow (220)Rn, in addition to (222)Rn. Such modified units are called RT EIC. When a set of R and RT EICs are collocated, it is possible to discriminate and measure both radon and thoron concentrations, using appropriate calibration factors (CFs) and algorithms. The EICs come in different volumes, providing different sensitivities. The thoron CFs for 58-, 210- and 960-ml volume R and RT pairs are, respectively, 2.8-, 18.7- and 89-V drop per (kBq m(-3) d ), respectively. These provide much wider sensitivities and ranges compared to alpha track-based passive radon-thoron discriminative monitors.

  19. Radon emanation chamber: High sensitivity measurements for the SuperNEMO experiment

    SciTech Connect

    Soulé, B.; Collaboration: SuperNEMO Collaboration; and others

    2013-08-08

    Radon is a well-known source of background in ββ0ν experiments due to the high Q{sub β} value of one of its daughter nucleus, {sup 214}Bi. The SuperNEMO collaboration requires a maximum radon contamination of 0.1 mBq/m{sup 3} inside its next-generation double beta decay detector. To reach such a low activity, a drastic screening process has been set for the selection of the detector's materials. In addition to a good radiopurity, a low emanation rate is required. To test this parameter, a Radon Emanation Setup is running at CENBG. It consists in a large emanation chamber connected to an electrostatic detector. By measuring large samples and having a low background level, this setup reaches a sensitivity of a few μ Bq. m{sup −2}. d{sup −1} and is able to qualify materials used in the construction of the SuperNEMO detector.

  20. RADON EXPOSURE ASSESSMENT AND DOSIMETRY APPLIED TO EPIDEMIOLOGY AND RISK ESTIMATION

    EPA Science Inventory

    Epidemiological studies of underground miners provide the primary basis for radon risk estimates for indoor exposures as well as mine exposures. A major source of uncertainty in these risk estimates is the uncertainty in radon progeny exposure estimates for the miners. In addit...

  1. OCCUPATIONAL EXPOSURE TO RADON IN DIFFERENT KINDS OF NON-URANIUM MINES.

    PubMed

    Fan, D; Zhuo, W; Zhang, Y

    2016-09-01

    For more accurate assessments of the occupational exposure to radon for miners, the individual monitoring was conducted by using an improved passive integrating (222)Rn monitor. A total of 120 miners in 3 different kinds of mines were monitored throughout a year. The results showed that the individual exposure to radon significantly varied with types of mines and work. Compared with the exposure to coal miners, the exposure to copper miners was much higher. Furthermore, it was found that the exposure might be overestimated if the environmental (222)Rn monitored by the passive integrating monitors was used for assessment. The results indicate that the individual monitoring of radon is necessary for an accurate assessment of radon exposure to miners, and radon exposure to non-uranium miners should also be assessed from the viewpoint of radiation protection.

  2. Lung cancer incidence attributable to residential radon exposure in Alberta in 2012

    PubMed Central

    Grundy, Anne; Brand, Kevin; Khandwala, Farah; Poirier, Abbey; Tamminen, Sierra; Friedenreich, Christine M.; Brenner, Darren R.

    2017-01-01

    Background: Radon is carcinogenic, and exposure to radon has been shown to increase the risk of lung cancer. The objective of this study was to quantify the proportion and number of lung cancer cases in Alberta in 2012 that could be attributed to residential radon exposure. Methods: We estimated the population attributable risk of lung cancer for residential radon using radon exposure data from the Cross-Canada Survey of Radon Concentrations in Homes from 2009-2011 and data on all-cause and lung cancer mortality from Statistics Canada from 2008-2012. We used cancer incidence data from the Alberta Cancer Registry for 2012 to estimate the total number of lung cancers attributable to residential radon exposure. Estimates were also stratified by sex and smoking status. Results: The mean geometric residential radon level in Alberta in 2011 was 71.0 Bq/m3 (geometric standard deviation 2.14). Overall, an estimated 16.6% (95% confidence interval 9.4%-29.8%) of lung cancers were attributable to radon exposure, corresponding to 324 excess attributable cancer cases. The estimated population attributable risk of lung cancer due to radon exposure was higher among those who had never smoked (24.8%) than among ever smokers (15.6%). However, since only about 10% of cases of lung cancer occur in nonsmokers, the estimated total number of excess cases was higher for ever smokers (274) than for never smokers (48). Interpretation: With about 17% of lung cancer cases in Alberta in 2012 attributable to residential radon exposure, exposure reduction has the potential to substantially reduce Alberta's lung cancer burden. As such, home radon testing and remediation techniques represent important cancer prevention strategies. PMID:28663187

  3. Effects of Radon Inhalation on Some Biophysical Properties of Blood in Rats

    NASA Astrophysics Data System (ADS)

    Essa, M. F.; Shahin, Fayez M.; Ahmed, Ashour M.; Abdel-Salam, Omar

    2013-03-01

    The major source of human exposure to natural radiation arises from the inhalation of radon (222Rn) gas. Exposure to high concentrations of radon 222Rn and its daughters for long period leads to pathological effects like lung cancer, leukaemia, skin cancer and kidney diseases. The present study was performed on rats to investigate the effect of radon exposure on the absorption spectra of hemoglobin. Measurements have been performed in a radon chamber where rats were exposed to radon for 1, 5 or 7 weeks. The inhalation of radon resulted in decrease in intensity of the absorption bands characterizing the hemoglobin molecular structure with increased radon doses.

  4. Lung Cancer Attributable to Indoor Radon Exposures in Two Radon--Prone Areas, Stei (Romania) and Torrelodones (Spain)

    SciTech Connect

    Dinu, Alexandra; Cosma, Constantin; Vasiliniuc, Stefan; Sainz, Carlos; Poncela, Luis Santiago Quindos

    2009-05-22

    Radon and radon progeny are present indoors, in houses and others dwellings, representing the most important contribution to dose from natural sources of radiation. Most studies have demonstrated an increased risk of lung cancer at high concentration of radon for both smokers and nonsmokers. For medium and low concentrations which are the typical residential radon levels, recent researches have also demonstrated increased risks of lung cancer for people exposed. The work presents a comparative analysis of the radon exposure data in the two radon--prone areas, Stei, Transylvania, (Romania), in the near of old Romanian uranium mines and in the granitic area of Torrelodones town, Sierra de Guadarrama (Spain). One important difference between the two studied areas is related to the houses built using uranium waste as construction material in Stei area. Measurements of indoor radon were performed in 280 dwellings (Romania) and 91 dwellings (Spain) by using nuclear track detectors, CR 39. The highest value measured in Stei area was 2650 Bq{center_dot}m{sup -3}. and 366 Bq{center_dot}m{sup -3} in the Spanish region. The results are compute with the BEIR VI report estimates using the age-duration model at an exposure rate below 2650 Bq{center_dot}m{sup -3}. A total of 233 lung cancer deaths were calculated in the Stei area for a period of 13 years (1994-2006), which is 116.82% higher than observed from the national statistics. In comparison, in Torrelodones area, a number of 276 deaths caused by lung cancer were estimated along a period of 13 years, which is 2.09 times higher than the number observed by authorities. This represents a significantly evidence that elevated risk can strongly be associated with cumulated radon exposure.

  5. Rural Parents' Perceptions of Risks Associated with Their Children's Exposure to Radon

    PubMed Central

    Hill, Wade G.; Butter¢eld, Patricia; Larsson, Laura S.

    2015-01-01

    Objectives To examine the level of awareness of radon issues, correlates of elective testing behaviors, and the accuracy of risk perception for radon exposures among rural residents receiving public health services. Design A cross-sectional design was used in which questionnaire data and household analytic data for radon levels were collected from a nonprobabilistic sample of rural households. Sample Thirty-one rural households with 71 adults and 60 children participated in the study. Primary household respondents were female (100%), Caucasian (97%), and primarily (94%) between 21 and 40 years of age. Measurement Questionnaire data consisted of knowledge and risk perception items about radon and all homes were tested for the presence of radon. Results The prevalence of high airborne radon (defined as ≥ 4pCi/l) was 32%. More than a third of the sample underestimated the seriousness of health effects of radon exposure, 39% disagreed that being around less radon would improve the long-term health of their children, and 52% were unsure whether radon could cause health problems. After adjusting for chance, only 21% of the subjects correctly understood their risk status. Conclusions This study provides preliminary evidence that low-income rural citizens do not understand their risk of radon exposure or the deleterious consequences of exposure. PMID:16961559

  6. Estimate of radon exposure in geothermal spas in Poland.

    PubMed

    Walczak, Katarzyna; Olszewski, Jerzy; Zmyślony, Marek

    2016-01-01

    Geothermal waters may contain soluble, radioactive radon gas. Spa facilities that use geothermal water may be a source of an increased radiation dose to people who stay there. It has been necessary to assess the exposure to radon among people: workers and visitors of spa centers that use geothermal waters. In 2013, workers of the Nofer Institute of Occupational Medicine measured concentrations of radon over the geothermal water surfaces in 9 selected Polish spa centers which use geothermal water for recreational and medicinal purposes. The measurements were performed by active dosimetry using Lucas scintillation cells. According to our research, the doses received by the personnel in Polish geothermal spas are < 0.6 mSv/year. In 1 of the investigated spas, the estimated annual dose to the staff may exceed 3 mSv/year. In Polish geothermal spas, neither the workers nor the visitors are at risk of receiving doses that exceed the safe limits. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  7. Radon exposure in uranium mining industry vs. exposure in tourist caves.

    PubMed

    Quindós Poncela, L; Fernández Navarro, P; Sainz Fernández, C; Gómez Arozamena, J; Bordonoba Perez, M

    2004-01-01

    There is a fairly general consensus among health physicists and radiation professionals that exposure to radon progeny is the largest and most variable contribution to the population's exposure to natural sources of radiation. However, this exposure is the subject of continuing debate concerning the validity of risk assessment and recommendations on how to act in radon-prone areas. The purpose of this contribution is to situate the radon issue in Spain in two very different settings. The first is a uranium mining industry located in Saelices el Chico (Salamanca), which is under strict control of the Spanish Nuclear Safety Council (CSN). We have measured radon concentrations in different workplaces in this mine over a five-year period. The second setting comprises four tourist caves, three of which are located in the province of Cantabria and the fourth on the Canary Island of Lanzarote. These caves are not subject to any administrative control of radiation exposure. Measured air 222Rn concentrations were used to estimate annual effective doses due to radon inhalation in the two settings, and dose values were found to be from 2 to 10 times lower in the uranium mine than in the tourist caves. These results were analysed in the context of the new European Basic Safety Standards Directive (EU-BSS, 1996).

  8. A physiologically based assessment of human exposure to radon released from groundwater.

    PubMed

    Yu, Donghan; Kim, Jin Kyu

    2004-02-01

    Most of the indoor radon comes directly from the soil beneath the foundation of a basement. Recently, radon from groundwater was found to make some contribution to the total inhalation risk associated with radon in indoor air. This study presents a realistic exposure assessment of a human to indoor radon released from groundwater. First, the prediction of indoor radon concentration released from groundwater was based on a three-compartment model that was developed to describe the transfer and distribution of the radon released from groundwater in a house through showers, washing clothes, and flushing toilets. Second, a physiologically based pharmacokinetic (PBPK) model for inhaled radon was developed and used to estimate tissue group concentrations in a human body. The PBPK model provides reasonable predictions of uptake, excretion, and distribution of retained radon among tissue groups in the body. Hence, the approach using the PBPK model combined with realistic indoor exposure scenarios predicts the radon concentrations in tissue groups in the body associated with the indoor radon pollution. The results obtained from the study will help increase the quantitative understanding of the risk assessment issues associated with the indoor radon released from the groundwater.

  9. Indoor residential radon exposure and risk of childhood acute myeloid leukaemia

    PubMed Central

    Steinbuch, M; Weinberg, C R; Buckley, J D; Robison, L L; Sandler, D P

    1999-01-01

    Exposure to radon has been identified as a risk factor for lung cancer in uranium miners, but evidence of adverse health effects due to indoor radon exposure is inconsistent. Ecological studies have suggested a correlation between indoor radon levels and leukaemia incidence. We evaluated the risk associated with indoor residential radon exposure within a larger interview-based case–control study of risk factors for childhood acute myeloid leukaemia (AML). A total of 173 cases and 254 controls met the eligibility criteria, and information was collected through telephone interviews with parents and analysis of alpha-track radon detectors placed in the home for a period of 1 year. No association was observed between radon exposure and risk of AML, with adjusted odds ratios of 1.2 (95% confidence interval (CI) 0.7–1.8) for 37–100 Bq m–3 and 1.1 (95% CI 0.6–2.0) for > 100 Bq m–3 compared with < 37 Bq m–3. Although there was an inverse association between radon level and AML risk among children < 2 years at diagnosis, among children ≥2 years, AML risk was increased among those with higher radon exposure. The observed association after age 2 is most likely due to chance. Overall, there was no association between residential radon and risk of childhood AML. © 1999 Cancer Research Campaign PMID:10555766

  10. Indoor residential radon exposure and risk of childhood acute myeloid leukaemia.

    PubMed

    Steinbuch, M; Weinberg, C R; Buckley, J D; Robison, L L; Sandler, D P

    1999-11-01

    Exposure to radon has been identified as a risk factor for lung cancer in uranium miners, but evidence of adverse health effects due to indoor radon exposure is inconsistent. Ecological studies have suggested a correlation between indoor radon levels and leukaemia incidence. We evaluated the risk associated with indoor residential radon exposure within a larger interview-based case-control study of risk factors for childhood acute myeloid leukaemia (AML). A total of 173 cases and 254 controls met the eligibility criteria, and information was collected through telephone interviews with parents and analysis of alpha-track radon detectors placed in the home for a period of 1 year. No association was observed between radon exposure and risk of AML, with adjusted odds ratios of 1.2 (95% confidence interval (CI) 0.7-1.8) for 37-100 Bq m(-3) and 1.1 (95% CI 0.6-2.0) for > 100 Bq m(-3) compared with < 37 Bq m(-3). Although there was an inverse association between radon level and AML risk among children < 2 years at diagnosis, among children > or = 2 years, AML risk was increased among those with higher radon exposure. The observed association after age 2 is most likely due to chance. Overall, there was no association between residential radon and risk of childhood AML.

  11. Lung cancer risk at low radon exposure rates in German uranium miners

    PubMed Central

    Kreuzer, M; Fenske, N; Schnelzer, M; Walsh, L

    2015-01-01

    Background: A determination of the risk of lung cancer at low levels of radon exposure is important for occupational radiation protection. Methods: The risk of death from lung cancer at low radon exposure rates was investigated in the subcohort of 26 766 German uranium miners hired in 1960 or later. Results: A clear association between lung cancer mortality (n=334 deaths) and cumulative exposure to radon in working level months (WLM) was found. The excess relative risk per WLM was 0.013 (95% confidence intervals: 0.007; 0.021). Conclusions: The present findings provide strong evidence for an increased lung cancer risk after long-term exposure to low radon exposure rates among Wismut miners. The results are compatible to those from residential radon studies and miner studies restricted to low levels. PMID:26393888

  12. Lung cancer and exposure to quartz and diesel exhaust in Swedish iron ore miners with concurrent exposure to radon.

    PubMed

    Bergdahl, Ingvar A; Jonsson, Håkan; Eriksson, Kåre; Damber, Lena; Järvholm, Bengt

    2010-08-01

    Studies of underground miners have documented an increased risk of lung cancer mainly linked to radon exposure but possibly influenced by other concurrent exposures. A cohort study was carried out in 8321 iron ore miners with low exposure to radon, employed in 1923-1998 and followed up for lung cancer in 1958-2000. Historical exposures to radon, crystalline silica and diesel exhaust were assessed. Data including exposure to radon, quartz and diesel exhaust from another mine with higher exposure to radon were reanalysed. Miners had increased risk for lung cancer (SIR 1.48 (95% CI 1.22 to 1.78), based on 112 cases during 227,000 person-years). The increased risk could not be explained by exposure to radon or diesel exhaust but was associated with exposure to crystalline silica: SIR 0.96 (0.53 to 1.62), 1.45 (1.10 to 1.87), 1.99 (1.31 to 2.90) and 1.77 (0.92 to 3.10) in groups with exposure to 0, 0-2, 2-5 and >5 mg years/m3, respectively. Reanalysis of data from the other mine indicated that quartz was a possible confounder in the analysis of relationship between radon and lung cancer. In the highest radon exposed group, the point estimate for the RR decreased from 5.65 to 3.90 when adjusting for concurrent exposure to quartz. Crystalline silica, a known carcinogen, probably affects lung cancer risk in iron ore miners. The main implication of the results is for interpretation of the dose-response curve for radon and lung cancer in underground iron ore miners. Since exposure to radon and quartz is often correlated, quartz exposure can be an important confounder.

  13. Using geographic information systems for radon exposure assessment in dwellings in the Oslo region, Norway

    NASA Astrophysics Data System (ADS)

    Kollerud, R.; Blaasaas, K.; Ganerød, G.; Daviknes, H. K.; Aune, E.; Claussen, B.

    2014-04-01

    Radon exposures were assigned to each residential address in the Oslo region using a geographic information system (GIS) that included indoor radon measurements. The results will be used in an epidemiologic study regarding leukemia and brain cancer. The model is based on 6% of measured residential buildings. High density of indoor radon measurements allowed us to develop a buffer model where indoor radon measurements found around each dwelling were used to assign a radon value for homes lacking radon measurement. Intraclass correlation coefficients (ICCs) were used to study the agreement between radon values from the buffer method, from indoor radon values of measured houses, and from a regression model constructed with radiometric data (eTh, eU) and bedrock geology. We obtained good agreement for both comparisons with ICC values between 0.54 and 0.68. GIS offers a useful variety of tools to study the indoor-radon exposure assessment. By using the buffer method it is more likely that geological conditions are similar within the buffer and this may take more into account the variation of radon over short distances. It is also probable that short-distance-scale correlation patterns express similarities in building styles and living habits. Although the method has certain limitations, we regard it as acceptable for use in epidemiological studies.

  14. EPA and Partners Announce National Plan to Prevent Lung Cancer Deaths Due to Radon Exposure

    EPA Pesticide Factsheets

    WASHINGTON - Today, the U.S. Environmental Protection Agency (EPA), American Lung Association, and other partners are announcing a strategy for preventing 3,200 lung cancer deaths annually by 2020 through radon exposure reduction strategies. Exposur

  15. Protection from radon exposure at home and at work in the directive 2013/59/Euratom.

    PubMed

    Bochicchio, F

    2014-07-01

    In recent years, international organisations involved in radiation protection and public health have produced new guidance, recommendations and requirements aiming better protection from radon exposure. These organisations have often worked in close collaboration in order to facilitate the establishment of harmonised standards. This paper deals with such standards and specifically with the new European Council Directive of 5 December 2013 on basic safety standards for protection against the dangers arising from exposure to ionising radiation (2013/59/Euratom). This new Directive has established a harmonised framework for the protection against ionising radiations, including protection from radon exposure. Requirements for radon in workplace are much more tightening than in previous Directive, and exposures to radon in dwellings are regulated for the first time in a Directive. Radon-related articles of this Directive are presented and discussed in this paper, along with some comparisons with other relevant international standards.

  16. Indoor radon exposure and lung cancer: a review of ecological studies.

    PubMed

    Yoon, Ji Young; Lee, Jung-Dong; Joo, So Won; Kang, Dae Ryong

    2016-01-01

    Lung cancer has high mortality and incidence rates. The leading causes of lung cancer are smoking and radon exposure. Indeed, the World Health Organization (WHO) has categorized radon as a carcinogenic substance causing lung cancer. Radon is a natural, radioactive substance; it is an inert gas that mainly exists in soil or rock. The gas decays into radioactive particles called radon progeny that can enter the human body through breathing. Upon entering the body, these radioactive elements release α-rays that affect lung tissue, causing lung cancer upon long-term exposure thereto. Epidemiological studies first outlined a high correlation between the incidence rate of lung cancer and exposure to radon progeny among miners in Europe. Thereafter, data and research on radon exposure and lung cancer incidence in homes have continued to accumulate. Many international studies have reported increases in the risk ratio of lung cancer when indoor radon concentrations inside the home are high. Although research into indoor radon concentrations and lung cancer incidence is actively conducted throughout North America and Europe, similar research is lacking in Korea. Recently, however, studies have begun to accumulate and report important data on indoor radon concentrations across the nation. In this study, we aimed to review domestic and foreign research into indoor radon concentrations and to outline correlations between indoor radon concentrations in homes and lung cancer incidence, as reported in ecological studies thereof. Herein, we noted large differences in radon concentrations between and within individual countries. For Korea, we observed tremendous differences in indoor radon concentrations according to region and year of study, even within the same region. In correlation analysis, lung cancer incidence was not found to be higher in areas with high indoor radon concentrations in Korea. Through our review, we identified a need to implement a greater variety of

  17. Lung cancer risk due to residential radon exposures: estimation and prevention.

    PubMed

    Truta, L A; Hofmann, W; Cosma, C

    2014-07-01

    Epidemiological studies proved that cumulative exposure to radon is the second leading cause of lung cancer, the world's most common cancer. The objectives of the present study are (i) to analyse lung cancer risk for chronic, low radon exposures based on the transformation frequency-tissue response (TF-TR) model formulated in terms of alpha particle hits in cell nuclei; (ii) to assess the percentage of attributable lung cancers in six areas of Transylvania where the radon concentration was measured and (iii) to point out the most efficient remediation measures tested on a pilot house in Stei, Romania. Simulations performed with the TF-TR model exhibit a linear dose-effect relationship for chronic, residential radon exposures. The fraction of lung cancer cases attributed to radon ranged from 9 to 28% for the investigated areas. Model predictions may represent a useful tool to complement epidemiological studies on lung cancer risk and to establish reasonable radiation protection regulations for human safety.

  18. Environmental radon studies in Mexico.

    PubMed

    Segovia, N; Gaso, M I; Armienta, M A

    2007-04-01

    Radon has been determined in soil, groundwater, and air in Mexico, both indoors and outdoors, as part of geophysical studies and to estimate effective doses as a result of radon exposure. Detection of radon has mainly been performed with solid-state nuclear track detectors (SSNTD) and, occasionally, with active detection devices based on silicon detectors or ionization chambers. The liquid scintillation technique, also, has been used for determination of radon in groundwater. The adjusted geometric mean indoor radon concentration (74 Bq m-3) in urban developments, for example Mexico City, is higher than the worldwide median concentration of radon in dwellings. In some regions, particularly hilly regions of Mexico where air pollution is high, radon concentrations are higher than action levels and the effective dose for the general population has increased. Higher soil radon levels have been found in the uranium mining areas in the northern part of the country. Groundwater radon levels are, in general, low. Soil-air radon contributing to indoor atmospheres and air pollution is the main source of increased exposure of the population.

  19. A Systematic Review of Radon Investigations Related to Public Exposure in Iran

    PubMed Central

    Pirsaheb, Meghdad; Najafi, Farid; Khosravi, Touba; Hemati, Lida

    2013-01-01

    Background The main sources of radiation exposure of all living organisms including humans are natural. In fact, radon and its decay products are the cause of 50% of the total dose that is derived from natural sources. Because of the significant health hazards of radon gas, its levels are widely monitored throughout the world. Accordingly, considerable researches have also been carried out in Iran. Objectives The aim of this research is a systematic review of the most recent studies associated with evaluation of radon gas levels in Iran. The main emphasis of this study was on public exposure to radon gas. Materials and Methods The most important route of exposure to such radiation is indoor places. In this investigation measurement of radon in water resources, tap water, indoor places and exhalation of radon from building material, the major sources of indoor radon gas emission, were considered. Results Significantly high levels of radon gas were found mostly in water and residenvial buildings. Conclusions It conclusion with regard to the study of building materials, granite stone and adobe coverings cannot be recommended for construction purposes. PMID:24719680

  20. Calculation of lifetime lung cancer risks associated with radon exposure, based on various models and exposure scenarios.

    PubMed

    Hunter, Nezahat; Muirhead, Colin R; Bochicchio, Francesco; Haylock, Richard G E

    2015-09-01

    The risk of lung cancer mortality up to 75 years of age due to radon exposure has been estimated for both male and female continuing, ex- and never-smokers, based on various radon risk models and exposure scenarios. We used risk models derived from (i) the BEIR VI analysis of cohorts of radon-exposed miners, (ii) cohort and nested case-control analyses of a European cohort of uranium miners and (iii) the joint analysis of European residential radon case-control studies. Estimates of the lifetime lung cancer risk due to radon varied between these models by just over a factor of 2 and risk estimates based on models from analyses of European uranium miners exposed at comparatively low rates and of people exposed to radon in homes were broadly compatible. For a given smoking category, there was not much difference in lifetime lung cancer risk between males and females. The estimated lifetime risk of radon-induced lung cancer for exposure to a concentration of 200 Bq m(-3) was in the range 2.98-6.55% for male continuing smokers and 0.19-0.42% for male never-smokers, depending on the model used and assuming a multiplicative relationship for the joint effect of radon and smoking. Stopping smoking at age 50 years decreases the lifetime risk due to radon by around a half relative to continuing smoking, but the risk for ex-smokers remains about a factor of 5-7 higher than that for never-smokers. Under a sub-multiplicative model for the joint effect of radon and smoking, the lifetime risk of radon-induced lung cancer was still estimated to be substantially higher for continuing smokers than for never smokers. Radon mitigation-used to reduce radon concentrations at homes-can also have a substantial impact on lung cancer risk, even for persons in their 50 s; for each of continuing smokers, ex-smokers and never-smokers, radon mitigation at age 50 would lower the lifetime risk of radon-induced lung cancer by about one-third. To maximise risk reductions, smokers in high-radon

  1. Enhancement of exposure to radon progeny as a consequence of passive smoking

    SciTech Connect

    Moghissi, A.A.; Seiler, M.C. )

    1989-01-01

    Among indoor air pollutants, radon and tobacco smoke take dominant positions. Because radon decay products have a relatively short residence time in air, the extent of the equilibrium between radon and its daughter products is linearly proportional to the carcinogenic risk, at least at low exposure levels. The relevant factor is the equilibrium factor F. This paper discusses the enhancement of radon exposure as a result of the presence of particulate matter originating from tobacco smoke. The presence of tobacco smoke provides a mechanism for radon progeny to be attached to inhalable particles and to remain in indoor air for a prolonged time. The results of our study indicate a significant increase in F as a consequence of passive smoking. These modeling efforts are consistent with the experimental data reported previously.

  2. Residential Radon Exposure and Incidence of Childhood Lymphoma in Texas, 1995–2011

    PubMed Central

    Peckham, Erin C.; Scheurer, Michael E.; Danysh, Heather E.; Lubega, Joseph; Langlois, Peter H.; Lupo, Philip J.

    2015-01-01

    There is warranted interest in assessing the association between residential radon exposure and the risk of childhood cancer. We sought to evaluate the association between residential radon exposure and the incidence of childhood lymphoma in Texas. The Texas Cancer Registry (n = 2147) provided case information for the period 1995–2011. Denominator data were obtained from the United States Census. Regional arithmetic mean radon concentrations were obtained from the Texas Indoor Radon Survey and linked to residence at diagnosis. Exposure was assessed categorically: ≤25th percentile (reference), >25th to ≤50th percentile, >50th to ≤75th percentile, and >75th percentile. Negative binomial regression generated adjusted incidence rate ratios (aIRR) and 95% confidence intervals (CI). We evaluated lymphoma overall and by subtype: Hodgkin (HL; n = 1248), Non-Hodgkin excluding Burkitt (non-BL NHL; n = 658), Burkitt (BL; n = 241), and Diffuse Large B-cell (DLBCL; n = 315). There was no evidence that residential radon exposure was positively associated with lymphoma overall, HL, or BL. Areas with radon concentrations >75th percentile had a marginal increase in DLBCL incidence (aIRR = 1.73, 95% CI: 1.03–2.91). In one of the largest studies of residential radon exposure and the incidence of childhood lymphoma, we found little evidence to suggest a positive or negative association; an observation consistent with previous studies. PMID:26404336

  3. Residential Radon Exposure and Incidence of Childhood Lymphoma in Texas, 1995-2011.

    PubMed

    Peckham, Erin C; Scheurer, Michael E; Danysh, Heather E; Lubega, Joseph; Langlois, Peter H; Lupo, Philip J

    2015-09-25

    There is warranted interest in assessing the association between residential radon exposure and the risk of childhood cancer. We sought to evaluate the association between residential radon exposure and the incidence of childhood lymphoma in Texas. The Texas Cancer Registry (n = 2147) provided case information for the period 1995-2011. Denominator data were obtained from the United States Census. Regional arithmetic mean radon concentrations were obtained from the Texas Indoor Radon Survey and linked to residence at diagnosis. Exposure was assessed categorically: ≤25th percentile (reference), >25th to ≤50th percentile, >50th to ≤75th percentile, and >75th percentile. Negative binomial regression generated adjusted incidence rate ratios (aIRR) and 95% confidence intervals (CI). We evaluated lymphoma overall and by subtype: Hodgkin (HL; n = 1248), Non-Hodgkin excluding Burkitt (non-BL NHL; n = 658), Burkitt (BL; n = 241), and Diffuse Large B-cell (DLBCL; n = 315). There was no evidence that residential radon exposure was positively associated with lymphoma overall, HL, or BL. Areas with radon concentrations >75th percentile had a marginal increase in DLBCL incidence (aIRR = 1.73, 95% CI: 1.03-2.91). In one of the largest studies of residential radon exposure and the incidence of childhood lymphoma, we found little evidence to suggest a positive or negative association; an observation consistent with previous studies.

  4. Evaluation of radon occurrence in groundwater from 16 geologic units in Pennsylvania, 1986–2015, with application to potential radon exposure from groundwater and indoor air

    USGS Publications Warehouse

    Gross, Eliza L.

    2017-05-11

    Results from 1,041 groundwater samples collected during 1986‒2015 from 16 geologic units in Pennsylvania, associated with 25 or more groundwater samples with concentrations of radon-222, were evaluated in an effort to identify variations in radon-222 activities or concentrations and to classify potential radon-222 exposure from groundwater and indoor air. Radon-222 is hereafter referred to as “radon.” Radon concentrations in groundwater greater than or equal to the proposed U.S. Environmental Protection Agency (EPA) maximum contaminant level (MCL) for public-water supply systems of 300 picocuries per liter (pCi/L) were present in about 87 percent of the water samples, whereas concentrations greater than or equal to the proposed alternative MCL (AMCL) for public water-supply systems of 4,000 pCi/L were present in 14 percent. The highest radon concentrations were measured in groundwater from the schists, gneisses, and quartzites of the Piedmont Physiographic Province.In this study, conducted by the U.S. Geological Survey in cooperation with the Pennsylvania Department of Health and the Pennsylvania Department of Environmental Protection, groundwater samples were aggregated among 16 geologic units in Pennsylvania to identify units with high median radon concentrations in groundwater. Graphical plots and statistical tests were used to determine variations in radon concentrations in groundwater and indoor air. Median radon concentrations in groundwater samples and median radon concentrations in indoor air samples within the 16 geologic units were classified according to proposed and recommended regulatory limits to explore potential radon exposure from groundwater and indoor air. All of the geologic units, except for the Allegheny (Pa) and Glenshaw (Pcg) Formations in the Appalachian Plateaus Physiographic Province, had median radon concentrations greater than the proposed EPA MCL of 300 pCi/L, and the Peters Creek Schist (Xpc), which is in the Piedmont

  5. Public exposure to radon in drinking water in Serbia.

    PubMed

    Todorovic, Natasa; Nikolov, Jovana; Forkapic, Sofija; Bikit, Istvan; Mrdja, Dusan; Krmar, Miodrag; Veskovic, Miroslav

    2012-03-01

    Radon is the main source of natural radiation that is received by population. The results of radon activity measurements in water from public drinking fountain, from bottled drinking water and from tap water in the city of Novi Sad, Serbia, are presented in this paper. The measurements were performed by RAD 7 radon detector manufactured by DURRIDGE COMPANY Inc. The corrected value of radon concentration in one sample exceeded the European Commission recommendation reference level for radon in drinking water of 100 Bql(-1). In order to make the correlation between radon and radium concentrations in the tap water and in the water from public drinking fountain, the gamma-spectrometric measurements were performed. The results of (222)Rn activity concentration measurements from soil in the city of Novi Sad using RAD 7 detector are presented.

  6. Modeling Joint Exposures and Health Outcomes for Cumulative Risk Assessment: The Case of Radon and Smoking

    PubMed Central

    Chahine, Teresa; Schultz, Bradley D.; Zartarian, Valerie G.; Xue, Jianping; Subramanian, SV; Levy, Jonathan I.

    2011-01-01

    Community-based cumulative risk assessment requires characterization of exposures to multiple chemical and non-chemical stressors, with consideration of how the non-chemical stressors may influence risks from chemical stressors. Residential radon provides an interesting case example, given its large attributable risk, effect modification due to smoking, and significant variability in radon concentrations and smoking patterns. In spite of this fact, no study to date has estimated geographic and sociodemographic patterns of both radon and smoking in a manner that would allow for inclusion of radon in community-based cumulative risk assessment. In this study, we apply multi-level regression models to explain variability in radon based on housing characteristics and geological variables, and construct a regression model predicting housing characteristics using U.S. Census data. Multi-level regression models of smoking based on predictors common to the housing model allow us to link the exposures. We estimate county-average lifetime lung cancer risks from radon ranging from 0.15 to 1.8 in 100, with high-risk clusters in areas and for subpopulations with high predicted radon and smoking rates. Our findings demonstrate the viability of screening-level assessment to characterize patterns of lung cancer risk from radon, with an approach that can be generalized to multiple chemical and non-chemical stressors. PMID:22016710

  7. Risks of Lung Cancer due to Radon Exposure among the Regions of Korea.

    PubMed

    Lee, Hye Ah; Lee, Won Kyung; Lim, Dohee; Park, Su Hyun; Baik, Sun Jung; Kong, Kyoung Ae; Jung-Choi, Kyunghee; Park, Hyesook

    2015-05-01

    Radon is likely the second most common cause of lung cancer after smoking. We estimated the lung cancer risk due to radon using common risk models. Based on national radon survey data, we estimated the population-attributable fraction (PAF) and the number of lung cancer deaths attributable to radon. The exposure-age duration (EAD) and exposure-age concentration (EAC) models were used. The regional average indoor radon concentration was 37.5 95 Bq/m(3). The PAF for lung cancer was 8.3% (European Pooling Study model), 13.5% in males and 20.4% in females by EAD model, and 19.5% in males and 28.2% in females by EAC model. Due to differences in smoking by gender, the PAF of radon-induced lung cancer deaths was higher in females. In the Republic of Korea, the risk of radon is not widely recognized. Thus, information about radon health risks is important and efforts are needed to decrease the associated health problems.

  8. Modeling joint exposures and health outcomes for cumulative risk assessment: the case of radon and smoking.

    PubMed

    Chahine, Teresa; Schultz, Bradley D; Zartarian, Valerie G; Xue, Jianping; Subramanian, S V; Levy, Jonathan I

    2011-09-01

    Community-based cumulative risk assessment requires characterization of exposures to multiple chemical and non-chemical stressors, with consideration of how the non-chemical stressors may influence risks from chemical stressors. Residential radon provides an interesting case example, given its large attributable risk, effect modification due to smoking, and significant variability in radon concentrations and smoking patterns. In spite of this fact, no study to date has estimated geographic and sociodemographic patterns of both radon and smoking in a manner that would allow for inclusion of radon in community-based cumulative risk assessment. In this study, we apply multi-level regression models to explain variability in radon based on housing characteristics and geological variables, and construct a regression model predicting housing characteristics using U.S. Census data. Multi-level regression models of smoking based on predictors common to the housing model allow us to link the exposures. We estimate county-average lifetime lung cancer risks from radon ranging from 0.15 to 1.8 in 100, with high-risk clusters in areas and for subpopulations with high predicted radon and smoking rates. Our findings demonstrate the viability of screening-level assessment to characterize patterns of lung cancer risk from radon, with an approach that can be generalized to multiple chemical and non-chemical stressors.

  9. Modeling Joint Exposures and Health Outcomes for Cumulative Risk Assessment: the Case of Radon and Smoking

    EPA Science Inventory

    Community-based cumulative risk assessment requires characterization of exposures to multiple chemical and non-chemical stressors, with consideration of how the non-chemical stressors may influence risks from chemical stressors. Residential radon provides an interesting case exam...

  10. Modeling Joint Exposures and Health Outcomes for Cumulative Risk Assessment: the Case of Radon and Smoking

    EPA Science Inventory

    Community-based cumulative risk assessment requires characterization of exposures to multiple chemical and non-chemical stressors, with consideration of how the non-chemical stressors may influence risks from chemical stressors. Residential radon provides an interesting case exam...

  11. Attributable mortality to radon exposure in Galicia, Spain. Is it necessary to act in the face of this health problem?

    PubMed Central

    2010-01-01

    Background Radon is the second risk factor for lung cancer after tobacco consumption and therefore it is necessary to know the burden of disease due to its exposure. The objective of this study is to estimate radon-attributable lung cancer mortality in Galicia, a high emission area located at the Northwest Spain. Methods A prevalence-based attribution method was applied. Prevalence of tobacco use and radon exposure were obtained from a previously published study of the same area. Attributable mortality was calculated for each of six possible risk categories, based on radon exposure and smoking status. Two scenarios were used, with 37 Bq/m3 and 148 Bq/m3 as the respective radon exposure thresholds. As the observed mortality we used lung cancer mortality for 2001 from the Galician mortality registry. Results Mortality exclusively attributable to radon exposure ranged from 3% to 5% for both exposure thresholds, respectively. Attributable mortality to combined exposure to radon and smoking stood at around 22% for exposures above 148 Bq/m3. Applying the United States Environmental Protection Agency (EPA) action level, radon has a role in 25% of all lung cancers. Conclusions Although the estimates have been derived from a study with a relatively limited sample size, these results highlight the importance of radon exposure as a cause of lung cancer and its effect in terms of disease burden. Radon mitigation activities in the study area must therefore be enforced. PMID:20482770

  12. Residential Radon Exposure and Skin Cancer Incidence in a Prospective Danish Cohort.

    PubMed

    Bräuner, Elvira Vaclavik; Loft, Steffen; Sørensen, Mette; Jensen, Allan; Andersen, Claus Erik; Ulbak, Kaare; Hertel, Ole; Pedersen, Camilla; Tjønneland, Anne; Krüger Kjær, Susanne; Raaschou-Nielsen, Ole

    2015-01-01

    Although exposure to UV radiation is the major risk factor for skin cancer, theoretical models suggest that radon exposure can contribute to risk, and this is supported by ecological studies. We sought to confirm or refute an association between long-term exposure to residential radon and the risk for malignant melanoma (MM) and non-melanoma skin cancer (NMSC) using a prospective cohort design and long-term residential radon exposure. During 1993-1997, we recruited 57,053 Danish persons and collected baseline information. We traced and geocoded all residential addresses of the cohort members and calculated radon concentrations at each address lived in from 1 January 1971 until censor date. Cox proportional hazards models were used to estimate incidence rate-ratios (IRR) and confidence intervals (CI) for the risk associated with radon exposure for NMSC and MM, and effect modification was assessed. Over a mean follow-up of 13.6 years of 51,445 subjects, there were 3,243 cases of basal cell carcinoma (BCC), 317 cases of squamous cell carcinoma (SCC) and 329 cases of MM. The adjusted IRRs per 100 Bq/m3 increase in residential radon levels for BCC, SCC and MM were 1.14 (95% CI: 1.03, 1.27), 0.90 (95% CI: 0.70, 1.37) and 1.08 (95% CI: 0.77, 1.50), respectively. The association between radon exposure and BCC was stronger among those with higher socio-economic status and those living in apartments at enrollment. Long-term residential radon exposure may contribute to development of basal cell carcinoma of the skin. We cannot exclude confounding from sunlight and cannot conclude on causality, as the relationship was stronger amongst persons living in apartments and non-existent amongst those living in single detached homes.

  13. Residential Radon Exposure and Skin Cancer Incidence in a Prospective Danish Cohort

    PubMed Central

    Bräuner, Elvira Vaclavik; Loft, Steffen; Sørensen, Mette; Jensen, Allan; Andersen, Claus Erik; Ulbak, Kaare; Hertel, Ole; Pedersen, Camilla; Tjønneland, Anne; Krüger Kjær, Susanne; Raaschou-Nielsen, Ole

    2015-01-01

    Background Although exposure to UV radiation is the major risk factor for skin cancer, theoretical models suggest that radon exposure can contribute to risk, and this is supported by ecological studies. We sought to confirm or refute an association between long-term exposure to residential radon and the risk for malignant melanoma (MM) and non-melanoma skin cancer (NMSC) using a prospective cohort design and long-term residential radon exposure. Methods During 1993–1997, we recruited 57,053 Danish persons and collected baseline information. We traced and geocoded all residential addresses of the cohort members and calculated radon concentrations at each address lived in from 1 January 1971 until censor date. Cox proportional hazards models were used to estimate incidence rate-ratios (IRR) and confidence intervals (CI) for the risk associated with radon exposure for NMSC and MM, and effect modification was assessed. Results Over a mean follow-up of 13.6 years of 51,445 subjects, there were 3,243 cases of basal cell carcinoma (BCC), 317 cases of squamous cell carcinoma (SCC) and 329 cases of MM. The adjusted IRRs per 100 Bq/m3 increase in residential radon levels for BCC, SCC and MM were 1.14 (95% CI: 1.03, 1.27), 0.90 (95% CI: 0.70, 1.37) and 1.08 (95% CI: 0.77, 1.50), respectively. The association between radon exposure and BCC was stronger among those with higher socio-economic status and those living in apartments at enrollment. Conclusion and Impact Long-term residential radon exposure may contribute to development of basal cell carcinoma of the skin. We cannot exclude confounding from sunlight and cannot conclude on causality, as the relationship was stronger amongst persons living in apartments and non-existent amongst those living in single detached homes. PMID:26274607

  14. Evaluation of Exposure to Radon Levels in Relation to Climatic Conditions at a Superfund Site.

    NASA Astrophysics Data System (ADS)

    Merrill, Elaine Alice

    1995-11-01

    Workers at a Superfund site have expressed concern that they may be exposed to elevated levels of radon gas, especially when meteorology is suitable. The site, formally a uranium processing site, stores the world's largest quantity of Ra-226 in two concrete silos. A layer of bentonite foam was placed over the contents of the silos in 1991 as a means to reduce the amount of radon emissions. Hourly real-time outdoor and indoor site radon data covering an entire year was statistically evaluated in relation to meteorological data covering the same time period. The hourly data was found to be lognormally distributed. Radon levels were highest during the early morning hours and during the summer months. Both outdoor and indoor concentrations were found to significantly vary with temporal and climatic factors, namely wind direction and relative humidity. Radon levels in the work areas were not found to be statistically different from off-site levels. Only radon levels in the vicinity of the storage silos, which is an exclusion zone, were significantly higher than levels off-site. Hence, the protective bentonite covering seems to be effective in reducing radon emissions. Two methods were used to calculate a hypothetical dose, based upon the annual average concentrations of radon in the work areas onsite, the BEIR IV method and the NCRP method, respectively. The BEIR IV method, which accounts for the activity ratio of radon and its daughter products, resulted in a slightly higher dose than the NCRP method. As expected, based on the mean concentrations, the hypothetical annual exposures from radon in the work areas of the site were below recommended exposure limits.

  15. Caves, mines and subterranean spaces: hazard and risk from exposure to radon.

    NASA Astrophysics Data System (ADS)

    Crockett, R. G. M.; Gillmore, G. K.

    2009-04-01

    Radon is a naturally occurring radioactive gas. It is colourless, odourless and chemically inert. The most hazardous isotope is 222Rn. Radon is formed in the natural environment by the radioactive decay of the element uranium (238U) and is a daughter product of daughter product of radium (226Ra). Uranium and radium are found, in differing degrees, in a wide range of rocks, soils (and building materials that are made from these). Radon concentrations in caves, e.g. limestone caves such as the Great Cave of Niah, Borneo, and caves in the Mendips and Peak District in the UK, has been documented and reveal that both (prehistoric) cave-dwellers and other users such as archaeologists are at risk from exposure to radon a naturally occurring radioactive gas. In general, but dependent on cave geometry and ventilation, radon concentration increases with increasing distance from the entrance, implying that the hazard also increases with distance from the entrance. With regard to mines and mining operations, as well as modern extraction of uranium and radium ores, both ores commonly occur alongside other metallic ores, e.g. silver at Schneeberg and Joachimsthal, and tin in Cornwall, and in some instances, waste from earlier metalliferious mining activity has itself been ‘mined' for uranium and/or radium ores. It is not solely the miners and other subterranean workers which are at risk, other workers and local inhabitants are also at risk. Also, that risk is not eliminated by protection against dust/airborne particulates: the risk from inhalation of radon is only reduced by reducing the inhalation of radon, i.e. use of breathing apparatus. Amongst the general population, radon is the second most significant cause of lung cancer behind tobacco smoking. Estimates vary but 6-9% of lung-cancers are attributable to radon and approximately 2% all cancer deaths are attributable to radon. These proportions will increase in higher-radon environments such as caves, mines and mining

  16. Health effects of radon exposure. Report of the Council on Scientific Affairs, American Medical Association

    SciTech Connect

    Not Available

    1991-04-01

    The consensus of scientists is that exposure to radon is hazardous, but disagreement exists about the effects of lower radon concentrations. Studies of underground miners have indicated that the risk of lung cancer increases in proportion to the intensity and duration of exposure to radon, and a recent authoritative report (BEIR IV) has concluded that estimates based on those studies are appropriate for estimating risks for occupants of homes. The BEIR IV report concluded that smoking cigarettes increases the risk of lung cancer associated with radon. Average radon levels in US homes range from 0.055 to 0.148 Bq/L (1.5 to 4 pCi/L), depending on the circumstances of measurement. Few studies have investigated health outcomes in occupants of homes with high radon levels. In advising patients about reducing the risks associated with radon, physicians should consider the costs, as well as the benefits, of remedial actions, and they should emphasize that, by far, the best way to avoid lung cancer is to stop smoking.

  17. Cancer incidence and mortality from exposure to radon progeny among Ontario uranium miners.

    PubMed

    Navaranjan, Garthika; Berriault, Colin; Do, Minh; Villeneuve, Paul J; Demers, Paul A

    2016-12-01

    The study objectives were to extend the follow-up of the Ontario uranium miners cohort, one of the largest cohorts of uranium miners with low cumulative exposures, to examine the relationship between radon exposure and lung cancer mortality and, for the first time incidence, and address gaps in the literature, including dose-response relationship between radon exposure and other cancer sites, and non-cancer mortality. The cohort of mine and mill workers was created using data from Canada's National Dose Registry and the Ontario Mining Master File. The follow-up for the cohort was recently extended for mortality (1954-2007) and for the first time includes cancer incidence (1969-2005). The Poisson regression was used to estimate relative risks (RR) and excess relative risks (ERR) and their 95% CIs with levels of cumulative radon exposure. The cohort consisted of 28 546 male miners with a mean cumulative radon exposure of 21.0 working level months (WLM). An increased risk of lung cancer and a dose-response relationship was observed with cumulative radon exposure. Miners exposed to >100 WLM demonstrated a twofold increase in the risk of lung cancer incidence (RR=1.89, CI 1.43 to 2.50) compared with the non-exposed group, and a linear ERR of 0.64/100 WLM (CI 0.43 to 0.85), with similar results observed for mortality. No association was observed for other cancer sites (stomach, leukaemia, kidney and extrathoracic airways) or non-cancer sites (cardiovascular diseases) with increasing cumulative exposure to radon. These findings suggest no increased risk of cancer sites other than lung or non-cancer mortality from relatively low cumulative exposure to radon. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  18. Continuous measurements of bronchial exposure induced by radon decay products during inhalation

    SciTech Connect

    Iwaoka, Kazuki; Tokonami, Shinji; Yonehara, Hidenori; Ishikawa, Tetsuo; Doi, Masahiro; Kobayashi, Yosuke; Yatabe, Yoshinori; Takahashi, Hiroyuki; Yamada, Yuji

    2007-09-15

    The deposition of radon decay products is not equal in each of the respiratory regions and as the presence of radon has been linked with an increase in lung cancer risk, it is important to calculate the deposition of radon decay products in each of the respiratory regions. Recently, many studies on the deposition of radon in respiratory regions have been simulated using wire screens. The systems and equipment used in those studies are not suitable for field measurements as their dimensions are relatively massive, nor can they measure continuously. We developed a continuous bronchial dosimeter (CBD) which is suitable for field measurements. It was designed with specifications that allow it to be remain compact. The CBD simulates the deposition of radon decay products in the different respiratory regions by the use of a combination of wire screens. Deposition in the simulated regions of the lung can be continuously estimated in various environments. The ratio of activities deposited in a simulated nasal cavity (N) and tracheobronchial (TB) regions was calculated from the results of simultaneous measurements using CBD-R (reference), CBD-N (nasal), and CBD-TB (tracheobronchial) measurement units. After aerosols were injected into the radon chamber, the ratio of N and TB depositions decreased. This results indicate that the CBD gave a good response to changes in the environment. It was found that the ratio of N and TB deposition also varied with time in each actual environment.

  19. Continuous measurements of bronchial exposure induced by radon decay products during inhalation

    NASA Astrophysics Data System (ADS)

    Iwaoka, Kazuki; Tokonami, Shinji; Yonehara, Hidenori; Ishikawa, Tetsuo; Doi, Masahiro; Kobayashi, Yosuke; Yatabe, Yoshinori; Takahashi, Hiroyuki; Yamada, Yuji

    2007-09-01

    The deposition of radon decay products is not equal in each of the respiratory regions and as the presence of radon has been linked with an increase in lung cancer risk, it is important to calculate the deposition of radon decay products in each of the respiratory regions. Recently, many studies on the deposition of radon in respiratory regions have been simulated using wire screens. The systems and equipment used in those studies are not suitable for field measurements as their dimensions are relatively massive, nor can they measure continuously. We developed a continuous bronchial dosimeter (CBD) which is suitable for field measurements. It was designed with specifications that allow it to be remain compact. The CBD simulates the deposition of radon decay products in the different respiratory regions by the use of a combination of wire screens. Deposition in the simulated regions of the lung can be continuously estimated in various environments. The ratio of activities deposited in a simulated nasal cavity (N) and tracheobronchial (TB) regions was calculated from the results of simultaneous measurements using CBD-R (reference), CBD-N (nasal), and CBD-TB (tracheobronchial) measurement units. After aerosols were injected into the radon chamber, the ratio of N and TB depositions decreased. This results indicate that the CBD gave a good response to changes in the environment. It was found that the ratio of N and TB deposition also varied with time in each actual environment.

  20. Radon exposure mediated changes in lung macrophage morphology and function, in vitro

    SciTech Connect

    Seed, T.M.; Niiro, G.K.; Kretz, N.D.

    1990-01-01

    Bronchopulmonary macrophages play a key role in the normal physiology of the respiratory system. Potential respiratory dysfunctions due to radon/radon daughter exposure-mediated damage of the macrophage lung cell population has been explored via in vitro technology. In this study, macrophages were isolated from lungs of normal healthy dogs by saline lavage, cultured for varying periods (0-96 h) in the presence or absence of radon gas, and assessed for radon dose-dependent changes in cell morphology and function. The in vitro culture procedure and the cell exposing system allowed for detailed alpha particle dosimetry, in relation to the assessed biological end points; i.e. (1) exposure-dependent changes in macrophage surface topography, (2) capacity to elaborate specific growth factor (CSF) essential for self maintenance, and (3) alterations in cell viability. Highlights of the morphologic assessment indicate that relatively low alpha particle doses arising from protracted radon/radon daughter exposure elicites pronounced topographic alterations of the exposed macrophage's cell surface. 27 refs., 7 figs., 1 tab.

  1. Two dimensions of measurement error: classical and Berkson error in residential radon exposure assessment.

    PubMed

    Heid, I M; Küchenhoff, H; Miles, J; Kreienbrock, L; Wichmann, H E

    2004-09-01

    Measurement error in exposure assessment is unavoidable. Statistical methods to correct for such errors rely upon a valid error model, particularly regarding the classification of classical and Berkson error, the structure and the size of the error. We provide a detailed list of sources of error in residential radon exposure assessment, stressing the importance of (a) the differentiation between classical and Berkson error and (b) the clear definitions of predictors and operationally defined predictors using the example of two German case-control studies on lung cancer and residential radon exposure. We give intuitive measures of error size and present evidence on both the error size and the multiplicative structure of the error from three data sets with repeated measurements of radon concentration. We conclude that modern exposure assessment should not only aim to be as accurate and precise as possible, but should also provide a model of the remaining measurement errors with clear differentiation of classical and Berkson components.

  2. Occupational radon exposure and lung cancer mortality: estimating intervention effects using the parametric G formula

    PubMed Central

    Edwards, Jessie K.; McGrath, Leah J.; Buckley, Jessie P.; Schubauer-Berigan, Mary K.; Cole, Stephen R.; Richardson, David B.

    2015-01-01

    Background Traditional regression analysis techniques used to estimate associations between occupational radon exposure and lung cancer focus on estimating the effect of cumulative radon exposure on lung cancer, while public health interventions are typically based on regulating radon concentration rather than workers’ cumulative exposure. Moreover, estimating the direct effect of cumulative occupational exposure on lung cancer may be difficult in situations vulnerable to the healthy worker survivor bias. Methods Workers in the Colorado Plateau Uranium Miners cohort (N=4,134) entered the study between 1950 and 1964 and were followed for lung cancer mortality through 2005. We use the parametric g-formula to compare the observed lung cancer mortality to the potential lung cancer mortality had each of 3 policies to limit monthly radon exposure been in place throughout follow-up. Results There were 617 lung cancer deaths over 135,275 person-years of follow-up. With no intervention on radon exposure, estimated lung cancer mortality by age 90 was 16%. Lung cancer mortality was reduced for all interventions considered, and larger reductions in lung cancer mortality were seen for interventions with lower monthly radon exposure limits. The most stringent guideline, the Mine Safety and Health Administration standard of 0.33 working level months, reduced lung cancer mortality from 16% to 10% (risk ratio 0.67; 95% confidence interval 0.61, 0.73). Conclusions This work illustrates the utility of the parametric g-formula for estimating the effects of policies regarding occupational exposures, particularly in situations vulnerable to the healthy worker survivor bias. PMID:25192403

  3. Radon: The Invisible Invader.

    ERIC Educational Resources Information Center

    School Leader, 1987

    1987-01-01

    A brief background on indoor radon and the health risks associated with radon exposure, with special emphasis on nonresidential buildings. One school district's experience in radon testing and monitoring is included. (MLF)

  4. Radon Testing in Schools.

    ERIC Educational Resources Information Center

    Wheeler, Robert

    1989-01-01

    Schools may be a significant source of radon exposure for children and staff. Describes radon detection kits and technologies, when to use them, and what action to take given the results of a radon test. (MLF)

  5. Radon: The Invisible Invader.

    ERIC Educational Resources Information Center

    School Leader, 1987

    1987-01-01

    A brief background on indoor radon and the health risks associated with radon exposure, with special emphasis on nonresidential buildings. One school district's experience in radon testing and monitoring is included. (MLF)

  6. Radon Testing in Schools.

    ERIC Educational Resources Information Center

    Wheeler, Robert

    1989-01-01

    Schools may be a significant source of radon exposure for children and staff. Describes radon detection kits and technologies, when to use them, and what action to take given the results of a radon test. (MLF)

  7. Radon exposure at a radioactive waste storage facility.

    PubMed

    Manocchi, F H; Campos, M P; Dellamano, J C; Silva, G M

    2014-06-01

    The Waste Management Department of Nuclear and Energy Research Institute (IPEN) is responsible for the safety management of the waste generated at all internal research centers and that of other waste producers such as industry, medical facilities, and universities in Brazil. These waste materials, after treatment, are placed in an interim storage facility. Among them are (226)Ra needles used in radiotherapy, siliceous cake arising from conversion processes, and several other classes of waste from the nuclear fuel cycle, which contain Ra-226 producing (222)Rn gas daughter.In order to estimate the effective dose for workers due to radon inhalation, the radon concentration at the storage facility has been assessed within this study. Radon measurements have been carried out through the passive method with solid-state nuclear track detectors (CR-39) over a period of nine months, changing detectors every month in order to determine the long-term average levels of indoor radon concentrations. The radon concentration results, covering the period from June 2012 to March 2013, varied from 0.55 ± 0.05 to 5.19 ± 0.45 kBq m(-3). The effective dose due to (222)Rn inhalation was further assessed following ICRP Publication 65.

  8. Clinical measures, smoking, radon exposure, and risk of lung cancer in uranium miners.

    PubMed Central

    Finkelstein, M M

    1996-01-01

    OBJECTIVES: Exposure to the radioactive daughters of radon is associated with increased risk of lung cancer in mining populations. An investigation of incidence of lung cancer following a clinical survey of Ontario uranium miners was undertaken to explore whether risk associated with radon is modified by factors including smoking, radiographic silicosis, clinical symptoms, the results of lung function testing, and the temporal pattern of radon exposure. METHODS: Miners were examined in 1974 by a respiratory questionnaire, tests of lung function, and chest radiography. A random selection of 733 (75%) of the original 973 participants was followed up by linkage to the Ontario Mortality and Cancer Registries. RESULTS: Incidence of lung cancer was increased threefold. Risk of lung cancer among miners who had stopped smoking was half that of men who continued to smoke. There was no interaction between smoking and radon exposure. Men with lung function test results consistent with airways obstruction had an increased risk of lung cancer, even after adjustment for cigarette smoking. There was no association between radiographic silicosis and risk of lung cancer. Lung cancer was associated with exposures to radon daughters accumulated in a time window four to 14 years before diagnosis, but there was little association with exposures incurred earlier than 14 years before diagnosis. Among the men diagnosed with lung cancer, the mean and median dose rates were 2.6 working level months (WLM) a year and 1.8 WLM/year in the four to 14 year exposure window. CONCLUSIONS: Risk of lung cancer associated with radon is modified by dose and time from exposure. Risk can be substantially decreased by stopping smoking. PMID:8943835

  9. Meta-analysis of residential exposure to radon gas and lung cancer.

    PubMed Central

    Pavia, Maria; Bianco, Aida; Pileggi, Claudia; Angelillo, Italo F.

    2003-01-01

    OBJECTIVES: To investigate the relation between residential exposure to radon and lung cancer. METHODS: A literature search was performed using Medline and other sources. The quality of studies was assessed. Adjusted odds ratios with 95% confidence intervals (CI) for the risk of lung cancer among categories of levels of exposure to radon were extracted. For each study, a weighted log-linear regression analysis of the adjusted odds ratios was performed according to radon concentration. The random effect model was used to combine values from single studies. Separate meta-analyses were performed on results from studies grouped with similar characteristics or with quality scores above or equal to the median. FINDINGS: Seventeen case-control studies were included in the meta-analysis. Quality scoring for individual studies ranged from 0.45 to 0.77 (median, 0.64). Meta-analysis based on exposure at 150 Bq/m3 gave a pooled odds ratio estimate of 1.24 (95% CI, 1.11-1.38), which indicated a potential effect of residential exposure to radon on the risk of lung cancer. Pooled estimates of fitted odds ratios at several levels of randon exposure were all significantly different from unity--ranging from 1.07 at 50 Bq/m3 to 1.43 at 250 Bq/m3. No remarkable differences from the baseline analysis were found for odds ratios from sensitivity analyses of studies in which > 75% of eligible cases were recruited (1.12, 1.00-1.25) and studies that included only women (1.29, 1.04-1.60). CONCLUSION: Although no definitive conclusions may be drawn, our results suggest a dose-response relation between residential exposure to radon and the risk of lung cancer. They support the need to develop strategies to reduce human exposure to radon. PMID:14758433

  10. Mitigation of three water supplies with high radon exposure to the employees.

    PubMed

    Ringer, W; Simader, M; Bernreiter, M; Kaineder, H

    2008-01-01

    A comprehensive survey to determine the occupational radiation exposure in water supplies and spas was conducted in the federal state of Upper Austria. The study comprises 45 water supplies. The limit for radon exposure of 6 MBq h m(-3) was exceeded by two water supplies (WS 33 and WS 42). In one water supply (WS 29), the level of 2 MBq h m(-3) was exceeded. These water supplies were mitigated. Prior to mitigation the main radon sources were identified. Mitigation measures were: evacuation of the outlet air of the vaporiser by means of a fan, installation of a fan in the exhaust air duct of the compensating reservoir, sealing of drain shafts and mechanical ventilation of the office. In all water supplies, the radon exposure was reduced to below 0.8 MBq h m(-3) at a cost of approx. euro 750 to euro 1000.

  11. Laboratory measurements on Radon exposure effects on local environmental temperature: implications for satellite TIR measurements

    NASA Astrophysics Data System (ADS)

    Martinelli, Giovanni; Tomasz Solecki, Andrzej; Eulalia Tchorz-Trzeciakiewicz, Dagmara; Karolina Grudzinska, Katarzyna

    2014-05-01

    Surface latent heat flux (SLHF) is proportional to the heat released by phase changes during solidification or evaporation or melting. Effects of SLHF on earth's surface have also been measured by satellite techniques able to measure thermal infrared radiation (TIR). Recent studies found a possible correlation between SLHF and earthquakes thus satellite techniques are widely utilized in researches on the possible link between SLHF and earthquakes. Possible fluctuations on SLHF values during seismic periods have been attributed to different causes like the expulsion from the ground of greenhouse gases or by Radon. In particular ionization processes due to Radon decay could lead to changes in air temperature. Laboratory experiments have been carried out to highlight the possible role of Radon in thermal environmental conditions of a laboratory controlled atmospheric volume. Samples of highly radioactive granite powder containing 600 Bq/kg of Radium that is 20 times higher than the average continental lithosphere content has been stored in a desiccator of 0,005 m3 volume for 30 days to accumulate radon 222Rn in the desiccator air. After radon accumulation the desiccator was placed inside a styrofoam chamber of 1x0.5x0.5 m size and the cover removed. The relative humidity of chamber air was 72% and temperature 24 oC. Experiment was monitored by an infrared camera Flir Therma CAM PM695 operating in the spectrum band 7,5-13 µm with thermal resolution 0,01ºC and a RadStar RS300-I Radon Detector/Monitor with 1 hour time resolution. Air temperature and humidity were monitored by a digital Terdens thermohygrometer. No significant thermal or humidity effects were observed.

  12. Radon and Thoron In-air Occupational Exposure Study within Selected Wine Cellars of the Western Cape (South Africa) and Associated Annual Effective Doses.

    PubMed

    Botha, R; Newman, R T; Lindsay, R; Maleka, P P

    2017-01-01

    This is the first known study of exposure of Rn (radon) and secondarily Rn (thoron) in-air activity concentrations assessed within nine selected wine cellars in four wine districts of the Western Cape (South Africa) and the associated annual occupational effective doses. E-PERM electret ion chambers (EIC) and RAD-7 α-detectors were used to perform these measurements. The radon in-air levels ranged from 12 ± 4 Bq m to 770 ± 40 Bq m within the nine selected wine cellars. Eight of the nine wine cellars (excluding results from cellar w-6) had a median radon in-air activity concentration of 48 ± 8 Bq m. Continuous thoron in-air activity concentration levels were also measured near an internal granite wall of the wine cellar w-6 (barrel room), where peak levels of up to 1,520 ± 190 Bq m and an average of 680 ± 30 Bq m were observed. The occupational annual effective dose due to radon and decay progeny exposure in-air within the selected wine cellars ranged from 0.08 ± 0.03 mSv to 4.9 ± 0.3 mSv with a median of 0.32 ± 0.04 mSv (Tmax = 2,000 h). The annual effective dose within the wine cellar (w-6) ranged up to a maximum of 2.5 ± 0.4 mSv (Tmax = 2000 h) due to exposure to thoron and decay progeny. In general, most of the wines cellars pose negligible associated health risk to personnel due to ionizing radiation exposure from the inhalation of radon and progeny. Under certain conditions (proximity and exposure time), caution should be exercised at wine cellar w-6 because of elevated thoron in-air levels.

  13. Modifiers of exposure--response estimates for lung cancer among miners exposed to radon progeny

    SciTech Connect

    Hornung, R.W.; Deddens, J.; Roscoe, R.

    1995-03-01

    The association between lung cancer and exposure to radon decay products has been well established. Despite agreement on this point, there is still some degree of uncertainty regarding characteristics of the exposure-response relationship. The use of studies of underground miners to estimate lung cancer risks due to residential radon exposure depends upon a better understanding of factors potentially modifying the exposure-response relationship. Given the diversity in study populations regarding smoking status, mining conditions, risk analysis methodology, and referent populations, the risk estimates across studies are quite similar. However, several factors partially contributing to differences in risk estimates are modified by attained age, time since last exposure, exposure rate, and cigarette smoking patterns. There is growing agreement across studies that relative risk decreases with attained age and time since last exposure. Several studies have also found an inverse exposure-rate effect, i.e., low exposure rates for protracted duration of exposure are more hazardous than equivalent cumulative exposures received at higher rates for shorter periods of time. Additionally, the interaction between radon exposure and cigarette smoking appears to be intermediate between additive and multiplicative in a growing number of studies. Quantitative estimates of these modifying factors are given using a new analysis of data from the latest update of the Colorado Plateau uranium miners cohort. 24 refs., 3 figs., 4 tabs.

  14. Children’s Exposure to Radon in Nursery and Primary Schools

    PubMed Central

    Branco, Pedro T. B. S.; Nunes, Rafael A. O.; Alvim-Ferraz, Maria C. M.; Martins, Fernando G.; Sousa, Sofia I. V.

    2016-01-01

    The literature proves an evident association between indoor radon exposure and lung cancer, even at low doses. This study brings a new approach to the study of children’s exposure to radon by aiming to evaluate exposure to indoor radon concentrations in nursery and primary schools from two districts in Portugal (Porto and Bragança), considering different influencing factors (occupation patterns, classroom floor level, year of the buildings’ construction and soil composition of the building site), as well as the comparison with IAQ standard values for health protection. Fifteen nursery and primary schools in the Porto and Bragança districts were considered: five nursery schools for infants and twelve for pre-schoolers (seven different buildings), as well as eight primary schools. Radon measurements were performed continuously. The measured concentrations depended on the building occupation, classroom floor level and year of the buildings’ construction. Although they were in general within the Portuguese legislation for IAQ, exceedances to international standards were found. These results point out the need of assessing indoor radon concentrations not only in primary schools, but also in nursery schools, never performed in Portugal before this study. It is important to extend the study to other microenvironments like homes, and in time to estimate the annual effective dose and to assess lifetime health risks. PMID:27043596

  15. Thoron detection with an active Radon exposure meter—First results

    SciTech Connect

    Irlinger, J. Wielunski, M.; Rühm, W.

    2014-02-15

    For state-of-the-art discrimination of Radon and Thoron several measurement techniques can be used, such as active sampling, electrostatic collection, delayed coincidence method, and alpha-particle-spectroscopy. However, most of the devices available are bulky and show high power consumption, rendering them unfeasible for personal exposition monitoring. Based on a Radon exposure meter previously realized at the Helmholtz Center Munich (HMGU), a new electronic prototype for Radon/Thoron monitoring is currently being developed, which features small size and weight. Operating with pin-diode detectors, the low-power passive-sampling device can be used for continuous concentration measurements, employing alpha-particle-spectroscopy and coincidence event registration to distinguish decays originating either from Radon or Thoron isotopes and their decay products. In open geometry, preliminary calibration measurements suggest that one count per hour is produced by a 11 Bq m{sup −3} Radon atmosphere or by a 15 Bq m{sup −3} Thoron atmosphere. Future efforts will concentrate on measurements in mixed Radon/Thoron atmospheres.

  16. Radon Sources and Associated Risk in Terms of Exposure and Dose

    PubMed Central

    Vogiannis, Efstratios G.; Nikolopoulos, Dimitrios

    2015-01-01

    Radon concerns the international scientific community from the early twentieth century, initially as radium emanation and nearly the second half of the century as a significant hazard to human health. The initial brilliant period of its use as medicine was followed by a period of intense concern for its health effects. Miners in Europe and later in the U.S were the primary target groups surveyed. Nowadays, there is a concrete evidence that radon and its progeny can cause lung cancer (1). Human activities may create or modify pathways increasing indoor radon concentration compared to outdoor background. These pathways can be controlled by preventive and corrective actions (2). Indoor radon and its short-lived progeny either attached on aerosol particles or free, compose an air mixture that carries a significant energy amount [Potential Alpha-Energy Concentration (PAEC)]. Prior research at that topic focused on the exposure on PAEC and the dose delivered by the human body or tissues. Special mention was made to the case of water workers due to inadequate data. Furthermore, radon risk assessment and relevant legislation for the dose delivered by man from radon and its progeny has been also reviewed. PMID:25601905

  17. Radon sources and associated risk in terms of exposure and dose.

    PubMed

    Vogiannis, Efstratios G; Nikolopoulos, Dimitrios

    2014-01-01

    Radon concerns the international scientific community from the early twentieth century, initially as radium emanation and nearly the second half of the century as a significant hazard to human health. The initial brilliant period of its use as medicine was followed by a period of intense concern for its health effects. Miners in Europe and later in the U.S were the primary target groups surveyed. Nowadays, there is a concrete evidence that radon and its progeny can cause lung cancer (1). Human activities may create or modify pathways increasing indoor radon concentration compared to outdoor background. These pathways can be controlled by preventive and corrective actions (2). Indoor radon and its short-lived progeny either attached on aerosol particles or free, compose an air mixture that carries a significant energy amount [Potential Alpha-Energy Concentration (PAEC)]. Prior research at that topic focused on the exposure on PAEC and the dose delivered by the human body or tissues. Special mention was made to the case of water workers due to inadequate data. Furthermore, radon risk assessment and relevant legislation for the dose delivered by man from radon and its progeny has been also reviewed.

  18. Thoron detection with an active Radon exposure meter—First results

    NASA Astrophysics Data System (ADS)

    Irlinger, J.; Wielunski, M.; Rühm, W.

    2014-02-01

    For state-of-the-art discrimination of Radon and Thoron several measurement techniques can be used, such as active sampling, electrostatic collection, delayed coincidence method, and alpha-particle-spectroscopy. However, most of the devices available are bulky and show high power consumption, rendering them unfeasible for personal exposition monitoring. Based on a Radon exposure meter previously realized at the Helmholtz Center Munich (HMGU), a new electronic prototype for Radon/Thoron monitoring is currently being developed, which features small size and weight. Operating with pin-diode detectors, the low-power passive-sampling device can be used for continuous concentration measurements, employing alpha-particle-spectroscopy and coincidence event registration to distinguish decays originating either from Radon or Thoron isotopes and their decay products. In open geometry, preliminary calibration measurements suggest that one count per hour is produced by a 11 Bq m-3 Radon atmosphere or by a 15 Bq m-3 Thoron atmosphere. Future efforts will concentrate on measurements in mixed Radon/Thoron atmospheres.

  19. Comprehensive investigation of radon exposure in Austrian tourist mines and caves.

    PubMed

    Gruber, V; Ringer, W; Gräser, J; Aspek, W; Gschnaller, J

    2014-11-01

    According to Austrian Law, dose assessments in workplaces with potentially enhanced radon exposures are mandatory since 2008, including tourist mines and caves. A pilot study was carried out to evaluate the situation to test the measurement methods and to specify the main parameters controlling the radon concentration in tourist mines and caves. Radon was measured in six mines and three caves for 1 y, along with determining thoron and equilibrium factors and taking into account climatic, geological and site-related effects. The radon concentrations have a seasonal dependence with maximum in summer and minimum in winter, related to natural ventilation. Radon concentrations in the karst caves were quite low, as it was in the salt mine, whereas radon concentrations in copper and silver mines were high. The dose assessment of the employees yielded doses above 6 mSv a(-1) only in the copper mine. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Carcinogenic risk coefficients at environmental levels of radon exposures: A microdosimetric approach

    SciTech Connect

    Zaider, M.; Varma, N.

    1996-06-01

    We report a microdosimetric-based evaluation of the effects of domestic exposure to radon. The risk coefficients obtained here are based on the microdosimetry of radon progeny alpha particles, on a function q(y) for in vivo radiogenic neoplasia, and on scaling A-bomb results (epidemiology + microdosimetry) to radon exposure. We do not use miner data, nor do we invoke such notions as quality factors, dose equivalent or equivalent dose. With basal cells as targets our estimated risk coefficients are in good agreement with the miner data, and thus a quality factor of about 20 (as suggested by ICRP 60) is not unreasonable. However, if we take as targets the secretory cells our risk coefficients are twice as large as those reported by BEIR-IV. The main uncertainty in these estimates remains the dosimetric model. 35 refs., 4 figs., 2 tabs.

  1. Dose estimation derived from the exposure to radon, thoron and their progeny in the indoor environment

    PubMed Central

    Ramola, R. C.; Prasad, Mukesh; Kandari, Tushar; Pant, Preeti; Bossew, Peter; Mishra, Rosaline; Tokonami, S.

    2016-01-01

    The annual exposure to indoor radon, thoron and their progeny imparts a major contribution to inhalation doses received by the public. In this study, we report results of time integrated passive measurements of indoor radon, thoron and their progeny concentrations that were carried out in Garhwal Himalaya with the aim of investigating significant health risk to the dwellers in the region. The measurements were performed using recently developed LR-115 detector based techniques. The experimentally determined values of radon, thoron and their progeny concentrations were used to estimate total annual inhalation dose and annual effective doses. The equilibrium factors for radon and thoron were also determined from the observed data. The estimated value of total annual inhalation dose was found to be 1.8 ± 0.7 mSv/y. The estimated values of the annual effective dose were found to be 1.2 ± 0.5 mSv/y and 0.5 ± 0.3 mSv/y, respectively. The estimated values of radiation doses suggest no important health risk due to exposure of radon, thoron and progeny in the study area. The contribution of indoor thoron and its progeny to total inhalation dose ranges between 13–52% with mean value of 30%. Thus thoron cannot be neglected when assessing radiation doses. PMID:27499492

  2. Dose estimation derived from the exposure to radon, thoron and their progeny in the indoor environment

    NASA Astrophysics Data System (ADS)

    Ramola, R. C.; Prasad, Mukesh; Kandari, Tushar; Pant, Preeti; Bossew, Peter; Mishra, Rosaline; Tokonami, S.

    2016-08-01

    The annual exposure to indoor radon, thoron and their progeny imparts a major contribution to inhalation doses received by the public. In this study, we report results of time integrated passive measurements of indoor radon, thoron and their progeny concentrations that were carried out in Garhwal Himalaya with the aim of investigating significant health risk to the dwellers in the region. The measurements were performed using recently developed LR-115 detector based techniques. The experimentally determined values of radon, thoron and their progeny concentrations were used to estimate total annual inhalation dose and annual effective doses. The equilibrium factors for radon and thoron were also determined from the observed data. The estimated value of total annual inhalation dose was found to be 1.8 ± 0.7 mSv/y. The estimated values of the annual effective dose were found to be 1.2 ± 0.5 mSv/y and 0.5 ± 0.3 mSv/y, respectively. The estimated values of radiation doses suggest no important health risk due to exposure of radon, thoron and progeny in the study area. The contribution of indoor thoron and its progeny to total inhalation dose ranges between 13–52% with mean value of 30%. Thus thoron cannot be neglected when assessing radiation doses.

  3. Does long term exposure to radon gas influence the properties of polymeric waterproof materials?

    NASA Astrophysics Data System (ADS)

    Navratilova Rovenska, Katerina; Jiranek, Martin; Kokes, Pavel; Wasserbauer, Richard; Kacmarikova, Veronika

    2014-01-01

    The technical state of buildings and the quality of the indoor environment depend on the quality of the waterproofing course and on the properties of the insulating materials that are applied, in particular on their durability, long-term functional reliability and resistance to corrosive effects of the subsoil. Underground water chemistry and soil bacteria are well-known corrosive agents. Our investigations indicate that the ageing process of waterproof materials can be significantly accelerated by alpha particles emitted by radon and radon progenies which are present in soil gas. Materials commonly available on the building market, e.g. LDPE and HDPE of various densities, PVC, TPO (thermoplastic polyolefin), PP (polypropylene) and EPDM were selected for our experimental study. The preliminary results for 3-year exposure to radon gas show a decrease in tensile strength to 60%, elongation to 80% and hardness to 95% for samples based on PE. The diffusion coefficient of radon for samples based on PVC decreased to 20% of the initial value after 1-year exposure to radon and soil bacteria.

  4. Estimation of past radon exposure to indoor radon from embedded (210)Po in household glass.

    PubMed

    Gusain, G S; Rautela, B S; Ramola, R C

    2012-11-01

    In the present investigation, the surface-deposited polonium activities were measured in houses in the Ukhimath region of Garhwal Himalaya, India. The surface-deposited (210)Po activity concentrations were found to vary from 0.7 to 15.40 Bq m(-2) with an average of 5.95 Bq m(-2). The radon concentration estimated on the basis of (210)Po activity was found to vary from 0.29 to 700 Bq m(-3) with an average value 242 Bq m(-3). The contemporary radon concentration in the area was found to vary from 13 to 181 Bq m(-3) with an average of 46 Bq m(-3). The annual effective dose due to (210)Po activity in houses in the Garhwal Himalaya region was found to vary from 0.61 to 13.33 mSv with an average of 5.15 mSv. Some worldwide studies have shown the relation between the increased risk of lung cancer and smoking habits. Data on smoking have also been collected from the same dwellings. The significance of this work is also discussed in detail from a radiation protection point of view.

  5. The Cellular and Molecular Carcinogenic Effects of Radon Exposure: A Review

    PubMed Central

    Robertson, Aaron; Allen, James; Laney, Robin; Curnow, Alison

    2013-01-01

    Radon-222 is a naturally occurring radioactive gas that is responsible for approximately half of the human annual background radiation exposure globally. Chronic exposure to radon and its decay products is estimated to be the second leading cause of lung cancer behind smoking, and links to other forms of neoplasms have been postulated. Ionizing radiation emitted during the radioactive decay of radon and its progeny can induce a variety of cytogenetic effects that can be biologically damaging and result in an increased risk of carcinogenesis. Suggested effects produced as a result of alpha particle exposure from radon include mutations, chromosome aberrations, generation of reactive oxygen species, modification of the cell cycle, up or down regulation of cytokines and the increased production of proteins associated with cell-cycle regulation and carcinogenesis. A number of potential biomarkers of exposure, including translocations at codon 249 of TP53 in addition to HPRT mutations, have been suggested although, in conclusion, the evidence for such hotspots is insufficient. There is also substantial evidence of bystander effects, which may provide complications when calculating risk estimates as a result of exposure, particularly at low doses where cellular responses often appear to deviate from the linear, no-threshold hypothesis. At low doses, effects may also be dependent on cellular conditions as opposed to dose. The cellular and molecular carcinogenic effects of radon exposure have been observed to be both numerous and complex and the elevated chronic exposure of man may therefore pose a significant public health risk that may extend beyond the association with lung carcinogenesis. PMID:23880854

  6. The cellular and molecular carcinogenic effects of radon exposure: a review.

    PubMed

    Robertson, Aaron; Allen, James; Laney, Robin; Curnow, Alison

    2013-07-05

    Radon-222 is a naturally occurring radioactive gas that is responsible for approximately half of the human annual background radiation exposure globally. Chronic exposure to radon and its decay products is estimated to be the second leading cause of lung cancer behind smoking, and links to other forms of neoplasms have been postulated. Ionizing radiation emitted during the radioactive decay of radon and its progeny can induce a variety of cytogenetic effects that can be biologically damaging and result in an increased risk of carcinogenesis. Suggested effects produced as a result of alpha particle exposure from radon include mutations, chromosome aberrations, generation of reactive oxygen species, modification of the cell cycle, up or down regulation of cytokines and the increased production of proteins associated with cell-cycle regulation and carcinogenesis. A number of potential biomarkers of exposure, including translocations at codon 249 of TP53 in addition to HPRT mutations, have been suggested although, in conclusion, the evidence for such hotspots is insufficient. There is also substantial evidence of bystander effects, which may provide complications when calculating risk estimates as a result of exposure, particularly at low doses where cellular responses often appear to deviate from the linear, no-threshold hypothesis. At low doses, effects may also be dependent on cellular conditions as opposed to dose. The cellular and molecular carcinogenic effects of radon exposure have been observed to be both numerous and complex and the elevated chronic exposure of man may therefore pose a significant public health risk that may extend beyond the association with lung carcinogenesis.

  7. In-vivo measurements of Pb-210 to determine cumulative exposure to radon daughters: A pilot study

    SciTech Connect

    Laurer, G.R.; Cohen, N. . Dept. of Environmental Medicine); Stark, A.; Ju, C. . Bureau of Environmental and Occupational Epidemiology)

    1991-05-01

    The objective of this study is to demonstrate the feasibility of estimating cumulative exposure of individuals to low concentrations of radon by measuring the amount of Pb-A-10 in their skeletons. This report presents progress to date establishing the validity of an vivo technique to measure skeletal burdens of Pb-210, accumulated from exposure to radon and radon progeny. With the skeletal content of Pb--210 and a model for Pb metabolism, cumulative exposure to radon and its short-lived daughters (radon/daughters) may be calculated for use in deriving a dose-response relationship between lung cancer and exposure to radon/daughters. Data are presented for 29 subjects exposed to above-average'' radon concentrations in their homes, showing the correlation between measured Pb--210 burdens, and measured pCi/l and WLM exposure estimates. Their results are compared to measurements of a population of 24 subject's presumed exposed to average concentrations. Measurements of a Pennsylvania family exposed for a year in a home with an extremely high radon content are also presented. Update of results of an ongoing study of the biological half-time of Pb--210 in man involving measurements, of a retired radiation worker with a 40 year old skeletal burden of Pb-210.

  8. Radiation exposure and dose to small mammals in radon-rich soils.

    PubMed

    Macdonald, C R; Laverock, M J

    1998-07-01

    Protection of the environment from radionuclide releases requires knowledge of the normal background levels of radiation exposure in the exposed biotic community and an estimate of the detriment caused by additional exposure. This study modeled the background exposure and dose to the lungs of small burrowing mammals from 222Rn in artificial burrows in radon-rich soils at a site in southeastern Manitoba. E-PERM chambers used to measure 222Rn in soil showed good reproducibility of measurement, with an average coefficient of variance (CV) of about 10%. Geometric mean (GM) 222Rn concentrations at nine randomly selected sites ranged from 5,490 Bq/m3 (GSD = 1.57, n = 7) to 41,000 Bq/m3 (GSD = 1.02, n = 5). Long-term monitoring of 222Rn concentrations in artificial burrows showed large variation within and between burrows and did not show consistent variation with season, orientation of the burrow opening, or levels of 226Ra in the soil. Annual GM concentrations in individual burrows ranged from 7,480 Bq/m3 (GSD = 1.60) to 18,930 Bq/m3 (GSD = 1.81) in burrows several meters apart. A grand GM of 9,990 Bq/m3 (GSD = 1.81, n = 214) was measured over the site for the year. An exposure model was constructed for five small mammal species based on their respiration rates and the number of hours spent in the burrow, active or hibernating, exposed to soil gas 222Rn, and the time spent out of the burrow exposed to atmospheric 222Rn. A background dose of 0.9 mGy/a from atmospheric 222Rn (40 Bq/m3) was estimated for a large-bodied (80 kg), nonburrowing animal living on the soil surface. The highest exposures (mJ/a) in burrowing mammals occurred in those species with the highest respiration rates. Hibernation accounted for a small fraction of total annual exposure (<5%) because of very low respiration rates during this period. Absorbed dose to lung (mGy/a) was highest in the pocket gopher and decreased in the larger animals because of larger lung mass. Using mean 222Rn concentrations

  9. ASSESSMENT OF THE EXPOSURE TO AND DOSE FROM RADON DECAY PRODUCTS IN NORMALLY OCCUPIED HOMES

    EPA Science Inventory

    The paper gives results of an assessment of the exposure to radon decay products in seven houses in northeastern U.S. and southeastern Canada. n two houses, a single individual smoked cigarettes. ariety of heating and cooking appliances were in the houses. hese studies provided 5...

  10. Estimating the distribution of lifetime cumulative radon exposures for California residents: A brief summary

    SciTech Connect

    Liu, K.S.; Chang, Y.L.; Hayward, S.B.; Gadgil, A.J.; Nero, A.V. Jr.

    1992-04-01

    We have used data on residential radon concentrations in California, together with information on California residents` moving histories and time-activity patterns, to estimate the distribution of lifetime cumulative exposures to radon 222. This distribution was constructed using Monte Carlo techniques to simulate the lifetime occupancy histories -- and associated radon exposures -- of 10,000 California residents. For standard male and female lifespans, the simulation sampled from transition probability matrices representing changes of residence within and between six regions of California, as well as into and out of the other United States, and then sampled from the appropriate regional (or national) distribution of indoor concentrations. The resulting distribution of lifetime cumulative exposures has a significantly narrower relative width than the distribution of California indoor concentrations, with only a small fraction -- less than 0.2% -- of the population having lifetime exposures equivalent to living during their lifetimes in a single home with a radon concentration of 148 Bq/m{sup 3} or more.

  11. ASSESSMENT OF THE EXPOSURE TO AND DOSE FROM RADON DECAY PRODUCTS IN NORMALLY OCCUPIED HOMES

    EPA Science Inventory

    The paper gives results of an assessment of the exposure to radon decay products in seven houses in northeastern U.S. and southeastern Canada. n two houses, a single individual smoked cigarettes. ariety of heating and cooking appliances were in the houses. hese studies provided 5...

  12. Exposure assessment of radon in the drinking water supplies: a descriptive study in Palestine

    PubMed Central

    2012-01-01

    Background Radon gas is considered as a main risk factor for lung cancer and found naturally in rock, soil, and water. The objective of this study was to determine the radon level in the drinking water sources in Nablus city in order to set up a sound policy on water management in Palestine. Methods This was a descriptive study carried out in two phases with a random sampling technique in the second phase. Primarily, samples were taken from 4 wells and 5 springs that supplied Nablus city residents. For each source, 3 samples were taken and each was analyzed in 4 cycles by RAD 7 device manufactured by Durridge Company. Secondly, from the seven regions of the Nablus city, three samples were taken from the residential tap water of each region. Regarding the old city, ten samples were taken. Finally, the mean radon concentration value for each source was calculated. Results The mean (range) concentration of radon in the main sources were 6.9 (1.5-23.4) Becquerel/liter (Bq/L). Separately, springs and wells' means were 4.6 Bq/L and 9.5 Bq/L; respectively. For the residential tap water in the 7 regions, the results of the mean (range) concentration values were found to be 1.0 (0.9-1.3) Bq/L. For the old city, the mean (range) concentration values were 2.3 (0.9-3.9) Bq/L. Conclusions Except for Al-Badan well, radon concentrations in the wells and springs were below the United State Environmental Protection Agency maximum contaminated level (U.S EPA MCL). The level was much lower for tap water. Although the concentration of radon in the tap water of old city were below the MCL, it was higher than other regions in the city. Preventive measures and population awareness on radon's exposure are recommended. PMID:22243625

  13. Exposure assessment of radon in the drinking water supplies: a descriptive study in Palestine.

    PubMed

    Al Zabadi, Hamzeh; Musmar, Samar; Issa, Shaza; Dwaikat, Nidal; Saffarini, Ghassan

    2012-01-13

    Radon gas is considered as a main risk factor for lung cancer and found naturally in rock, soil, and water. The objective of this study was to determine the radon level in the drinking water sources in Nablus city in order to set up a sound policy on water management in Palestine. This was a descriptive study carried out in two phases with a random sampling technique in the second phase. Primarily, samples were taken from 4 wells and 5 springs that supplied Nablus city residents. For each source, 3 samples were taken and each was analyzed in 4 cycles by RAD 7 device manufactured by Durridge Company. Secondly, from the seven regions of the Nablus city, three samples were taken from the residential tap water of each region. Regarding the old city, ten samples were taken. Finally, the mean radon concentration value for each source was calculated. The mean (range) concentration of radon in the main sources were 6.9 (1.5-23.4) Becquerel/liter (Bq/L). Separately, springs and wells' means were 4.6 Bq/L and 9.5 Bq/L; respectively. For the residential tap water in the 7 regions, the results of the mean (range) concentration values were found to be 1.0 (0.9-1.3) Bq/L. For the old city, the mean (range) concentration values were 2.3 (0.9-3.9) Bq/L. Except for Al-Badan well, radon concentrations in the wells and springs were below the United State Environmental Protection Agency maximum contaminated level (U.S EPA MCL). The level was much lower for tap water. Although the concentration of radon in the tap water of old city were below the MCL, it was higher than other regions in the city. Preventive measures and population awareness on radon's exposure are recommended.

  14. Radon exposure of the skin: II. Estimation of the attributable risk for skin cancer incidence.

    PubMed

    Charles, M W

    2007-09-01

    A preceding companion paper has reviewed the various factors which form the chain of assumptions that are necessary to support a suggested link between radon exposure and skin cancer in man. Overall, the balance of evidence was considered to be against a causal link between radon exposure and skin cancer. One factor against causality is evidence, particularly from animal studies, that some exposure of the hair follicles and/or the deeper dermis, as well as the inter-follicular epidermis, is required-beyond the range of naturally occurring alpha particles. On this basis any skin cancer risk due to radon progeny would be due only to beta and gamma components of equivalent dose, which are 10-100 times less than the alpha equivalent dose to the basal layer. Notwithstanding this conclusion against causality, calculations have been carried out of attributable risk (ATR, the proportion of cases occurring in the total population which can be explained by radon exposure) on the conservative basis that the target cells are, as is often assumed, in the basal layer of the epidermis. An excess relative risk figure is used which is based on variance weighting of the data sources. This is 2.5 times lower than the value generally used. A latent period of 20 years and an RBE of 10 are considered more justifiable than the often used values of 10 years and 20 respectively. These assumptions lead to an ATR of approximately 0.7% (0.5-5%) at the nominal UK indoor radon level of 20 Bq m(-3). The range reflects uncertainties in plate-out. Previous higher estimates by various authors have made more pessimistic assumptions. There are some indications that radon progeny plate-out may be elevated out of doors, particularly due to rainfall. Although average UK outdoor radon levels ( approximately 4 Bq m(-3)) are much less than average indoor levels, and outdoor residence time is on average about 10%, this might have the effect of increasing the ATR several-fold. This needs considerable further

  15. General public's and physicians' perception of health risk associated with radon exposure in the state of Azad Jammu and Kashmir.

    PubMed

    Rafique, Muhammad; Jabeen, Shahida; Shahzad, M Ikram

    2008-01-01

    To conduct a radon awareness survey to examine the level of awareness and risk perception of indoor radon exposure among the general public, medical students, and physicians of the state of Azad Jammu and Kashmir, given that long-term exposure to indoor radon increases lifetime risk of lung cancer and may pose a substantial threat to public health. Cross-sectional survey. Households by telephone (500), interviews with menial laborers (200), questionnaires to shopkeepers and government employees (1,000), undergraduates (200), social science graduates (1,500), science graduates (1,500), medical students (325), and physicians (100). Familiarity with radioactivity and the nature and health hazards of radiation and radon. Significance of data trends was measured using the Kruskal-Wallis test. About 30% people (excluding medical students and physicians) were aware of radon, and about 6% had knowledgeable awareness of radon. About 80% of the medical students and physicians had heard about radon and about 30.5% of them had knowledgeable awareness about radon and its hazards. The study suggested a positive relationship of awareness of radon and its hazards with the educational level of people.

  16. Radon-Induced Health Effects

    NASA Astrophysics Data System (ADS)

    Muirhead, C. R.

    The following sections are included: * Lung Cancer * Studies of miners * Estimates of lifetime risk associated with indoor radon exposure * Factors that may affect risk estimates * Sex and age at exposure * Joint effect of radon and smoking * Exposure rate * Epidemiological studies of lung cancer and indoor radon exposure * Cancers Other Than Lung * Dosimetry * Epidemiological studies * Studies of miners * Indoor radon exposure * Concluding Remarks * References

  17. Assessment of the exposure to and dose from radon decay products in normally occupied homes

    SciTech Connect

    Hopke, P.K.; Jensen, B.; Li, C.S.; Montassier, N.; Wasiolek, P.; Cavallo, A.J.; Gatsby, K.; Socolow, R.H.; James, A.C.

    1995-05-01

    The exposure to radon decay products has been assessed in seven homes in the northeastern United States and southeastern Canada. In two of the houses, there was a single individual who smoked cigarettes. There were a variety of heating and cooking appliances among these homes. These studies have provide 565 measurements of the activity-weighted size distributions in these houses. The median value for the equilibrium factor was 0.408 as compared with the previously employed value of 0.50. Using the recently adopted ICRP lung deposition and dosimetry model, the hourly equivalent lung dose rate per unit, radon exposure was estimated for each measured size distribution. Differences between houses with smokers present and absent were noted in the exposure conditions, but the resulting dose rate per unit of radon gas concentration was essentially the same for the two groups. Expressed in terms of ICRP`s unit of effective dose for members of the public, the mean dose rate conversion coefficient with respect to radon gas concentration found in this study was 3.8 nSv h{sup -} Bq{sup -} m{sup -3}. 26 refs., 8 figs., 3 tabs.

  18. Estimated risks of radon-induced lung cancer for different exposure profiles based on the new EPA model.

    PubMed

    Chen, Jing

    2005-04-01

    Radon is a naturally occurring radioactive gas. When inhaled, radon can cause mutations that lead to lung cancer. Some new epidemiologic studies indicate that indoor radon is a public health problem. The BEIR VI report outlined its preferred two risk models for the combined effects of smoking and exposure to radon progeny, and listed the estimated risk to ever-smokers and never-smokers of both sexes due to lifetime exposure. However, exposures for shorter periods of time are of practical interest since exposure to elevated levels of radon may occur and end at any age. This study aims to produce practical tables of lifetime relative risks for exposures between any two age intervals from 0 to 110, and for various radon concentrations found in homes from 100 to 1,000 Bq m(-3). The calculations are based on the risk model developed recently by U.S. Environmental Protection Agency. The EPA's risk model is a single model that gives risk values midway between those obtained from the two BEIR VI preferred models. The detailed tables provide a clearer view of the age groups at higher risk and the effect of exposure duration. The results will help radiation protection practitioners to better communicate indoor radon risk to members of the public.

  19. Indoor radon.

    PubMed

    Polpong, P; Bovornkitti, S

    1998-01-01

    The naturally radioactive but chemically inert gas, radon, is formed from the radioactive decay of radium which is part of the uranium series. Radon gas, which has a half life of 3.8 days, must escape from soil particles through air-filled pores in order to enter the atmosphere following the decay of radium. The concentration of radon in the atmosphere varies, depending on the place, time, height above the ground and meteorological conditions. It is thus an inescapable source of radiation exposure, both at home and at work. The potential hazards posed by exposure to radiation from indoor radon gas and its daughter products are of great concern worldwide. Noting of an excessive lung cancer risk among several groups of underground miners exposed to radon and its daughter products, studies on radon concentrations in the workplace and in dwellings have been conducted in many countries. The results have shown that the distribution of radon concentrations are approximately lognormal from which population weighted; the arithmetic mean of radon concentration of 40 Bq.m-3 has been adopted worldwide for dwellings and workplaces. The principal methods for reducing a high indoor radon concentration are: reducing the radon supply by reversing the pressure difference between the building and the soil; raising the resistance of the foundations to soil gas entry; removing the radon sources such as water or underlying soil; diluting the concentration by increasing the ventilation rate; and reducing the concentration of radon progeny by filtering and increasing the circulation of indoor air. Buildings which have a radon concentration higher than 200 Bq.m-3 should be investigated by the national authorities concerned; meanwhile, householders should be advised to take simple temporary precautions, such as increasing ventilation, until a permanent remedy can be effected.

  20. Computer program for the sensitivity calculation of a CR-39 detector in a diffusion chamber for radon measurements

    SciTech Connect

    Nikezic, D. Stajic, J. M.; Yu, K. N.

    2014-02-15

    Computer software for calculation of the sensitivity of a CR-39 detector closed in a diffusion chamber to radon is described in this work. The software consists of two programs, both written in the standard Fortran 90 programming language. The physical background and a numerical example are given. Presented software is intended for numerous researches in radon measurement community. Previously published computer programs TRACK-TEST.F90 and TRACK-VISION.F90 [D. Nikezic and K. N. Yu, Comput. Phys. Commun. 174, 160 (2006); D. Nikezic and K. N. Yu, Comput. Phys. Commun. 178, 591 (2008)] are used here as subroutines to calculate the track parameters and to determine whether the track is visible or not, based on the incident angle, impact energy, etching conditions, gray level, and visibility criterion. The results obtained by the software, using five different V functions, were compared with the experimental data found in the literature. Application of two functions in this software reproduced experimental data very well, while other three gave lower sensitivity than experiment.

  1. Computer program for the sensitivity calculation of a CR-39 detector in a diffusion chamber for radon measurements

    NASA Astrophysics Data System (ADS)

    Nikezic, D.; Yu, K. N.; Stajic, J. M.

    2014-02-01

    Computer software for calculation of the sensitivity of a CR-39 detector closed in a diffusion chamber to radon is described in this work. The software consists of two programs, both written in the standard Fortran 90 programming language. The physical background and a numerical example are given. Presented software is intended for numerous researches in radon measurement community. Previously published computer programs TRACK_TEST.F90 and TRACK_VISION.F90 [D. Nikezic and K. N. Yu, Comput. Phys. Commun. 174, 160 (2006); D. Nikezic and K. N. Yu, Comput. Phys. Commun. 178, 591 (2008)] are used here as subroutines to calculate the track parameters and to determine whether the track is visible or not, based on the incident angle, impact energy, etching conditions, gray level, and visibility criterion. The results obtained by the software, using five different V functions, were compared with the experimental data found in the literature. Application of two functions in this software reproduced experimental data very well, while other three gave lower sensitivity than experiment.

  2. Canadian Lung Cancer Relative Risk from Radon Exposure for Short Periods in Childhood Compared to a Lifetime

    PubMed Central

    Chen, Jing

    2013-01-01

    Long-term exposure to elevated indoor radon concentrations has been determined to be the second leading cause of lung cancer in adults after tobacco smoking. With the establishment of a National Radon Program in Canada in 2007 thousands of homes across the country have been tested for radon. Although the vast majority of people are exposed to low or moderate radon concentrations; from time to time; there are homes found with very high concentrations of radon. Among those living in homes with very high radon concentrations, it is typically parents of young children that demonstrate a great deal of concern. They want to know the equivalent risk in terms of the lifetime relative risk of developing lung cancer when a child has lived in a home with high radon for a few years. An answer to this question of risk equivalency is proposed in this paper. The results demonstrate clearly that the higher the radon concentration; the sooner remedial measures should be undertaken; as recommended by Health Canada in the Canadian radon guideline. PMID:23698696

  3. Case-control study of lung cancer risk from residential radon exposure in Worcester county, Massachusetts.

    PubMed

    Thompson, Richard E; Nelson, Donald F; Popkin, Joel H; Popkin, Zenaida

    2008-03-01

    A study of lung cancer risk from residential radon exposure and its radioactive progeny was performed with 200 cases (58% male, 42% female) and 397 controls matched on age and sex, all from the same health maintenance organization. Emphasis was placed on accurate and extensive year-long dosimetry with etch-track detectors in conjunction with careful questioning about historic patterns of in-home mobility. Conditional logistic regression was used to model the outcome of cancer on radon exposure, while controlling for years of residency, smoking, education, income, and years of job exposure to known or potential carcinogens. Smoking was accounted for by nine categories: never smokers, four categories of current smokers, and four categories of former smokers. Radon exposure was divided into six categories (model 1) with break points at 25, 50, 75, 150, and 250 Bq m, the lowest being the reference. Surprisingly, the adjusted odds ratios (AORs) were, in order, 1.00, 0.53, 0.31, 0.47, 0.22, and 2.50 with the third category significantly below 1.0 (p < 0.05), and the second, fourth, and fifth categories approaching statistical significance (p < 0.1). An alternate analysis (model 2) using natural cubic splines allowed calculating AORs as a continuous function of radon exposure. That analysis produces AORs that are substantially less than 1.0 with borderline statistical significance (0.048 < or = p < or = 0.05) between approximately 85 and 123 Bq m. College-educated subjects in comparison to high-school dropouts have a significant reduction in cancer risk after controlling for smoking, years of residency, and job exposures with AOR = 0.30 (95% CI: 0.13, 0.69), p = 0.005 (model 1).

  4. Assessment of external gamma exposure and radon levels in a dwelling constructed with phosphogypsum plates.

    PubMed

    Máduar, M F; Campos, M P; Mazzilli, B P; Villaverde, F L

    2011-06-15

    Phosphogypsum, a fertilizer industry by-product, is being worldwide stockpiled, posing environmental concerns. Since this material contains natural radionuclides in significant concentrations, its use as a building material has radiological implications. In order to confirm the feasibility of the use of a new material mainly composed by phosphogypsum, an experimental house was built, having some of its rooms entirely lined with this material. Measurements of samples of phosphogypsum plates from different origins resulted in values of 0.2 to 2.6 for the external radiation index, thus justifying a more detailed investigation. In this paper, the application of a previously developed computational model to forecast external doses indoors is described. A comprehensive radiological evaluation is being performed, including measurement of the external gamma exposure and radon concentrations in one of the rooms of the house. The results show that the annual increment in the effective dose to an inhabitant of the house will remain below the 1 mSv limit for every reasonable scenario. The radon measurements were carried out over a period of 18 months, in order to determine the long-term average levels of the indoor radon concentrations. The results obtained are below 200 Bq m(-3), the recommended investigation level for radon.

  5. Radon exposure and cancers other than lung cancer in Swedish iron miners

    SciTech Connect

    Darby, S.C.; Whitley, E.; Radford, E.P.

    1995-03-01

    Data are presented on the risks of cancers other than lung cancer in a cohort of iron miners from northern Sweden occupationally exposed to elevated levels of the radioactive gas radon. Compared with rates for the four northernmost counties of Sweden, mortality was increased for all cancers other than lung cancer (ratio of observed to expected deaths 1.21, 95% confidence interval 1.03-1.41), stomach cancer (ratio of observed to expect- ed deaths 1.45, 95% confidence interval 1.04-1.98), and rectal cancer (ratio of observed to expected deaths 1.94, 95% confidence interval 1.03-3.31). Despite these overall increases, mortality was not significantly associated with cumulative exposure to radon, either for all cancers other than lung cancer or for any site of cancer other than lung cancer individually. However, the data from this cohort on its own have limited power; and for several sites of cancer the data in this study would be consistent with a radon-related increase. Further study of cancers other than lung cancer in populations exposed to radon is required. 8 refs., 2 tabs.

  6. Indoor Radon: The Deadliest Pollutant.

    ERIC Educational Resources Information Center

    Kerr, Richard A.

    1988-01-01

    Describes the origin, occurrence, and effects of radon gas. Cites studies which attribute 5,000 to 20,000 deaths per year to radon exposure and the synergistic effect between radon and smoking. Explains ways to reduce risks. (RT)

  7. Indoor Radon: The Deadliest Pollutant.

    ERIC Educational Resources Information Center

    Kerr, Richard A.

    1988-01-01

    Describes the origin, occurrence, and effects of radon gas. Cites studies which attribute 5,000 to 20,000 deaths per year to radon exposure and the synergistic effect between radon and smoking. Explains ways to reduce risks. (RT)

  8. Domestic Radon Exposure and Risk of Childhood Cancer: A Prospective Census-Based Cohort Study

    PubMed Central

    Hauri, Dimitri; Spycher, Ben; Huss, Anke; Zimmermann, Frank; Grotzer, Michael; von der Weid, Nicolas; Weber, Damien; Spoerri, Adrian; Kuehni, Claudia E.

    2013-01-01

    Background: In contrast with established evidence linking high doses of ionizing radiation with childhood cancer, research on low-dose ionizing radiation and childhood cancer has produced inconsistent results. Objective: We investigated the association between domestic radon exposure and childhood cancers, particularly leukemia and central nervous system (CNS) tumors. Methods: We conducted a nationwide census-based cohort study including all children < 16 years of age living in Switzerland on 5 December 2000, the date of the 2000 census. Follow-up lasted until the date of diagnosis, death, emigration, a child’s 16th birthday, or 31 December 2008. Domestic radon levels were estimated for each individual home address using a model developed and validated based on approximately 45,000 measurements taken throughout Switzerland. Data were analyzed with Cox proportional hazard models adjusted for child age, child sex, birth order, parents’ socioeconomic status, environmental gamma radiation, and period effects. Results: In total, 997 childhood cancer cases were included in the study. Compared with children exposed to a radon concentration below the median (< 77.7 Bq/m3), adjusted hazard ratios for children with exposure ≥ the 90th percentile (≥ 139.9 Bq/m3) were 0.93 (95% CI: 0.74, 1.16) for all cancers, 0.95 (95% CI: 0.63, 1.43) for all leukemias, 0.90 (95% CI: 0.56, 1.43) for acute lymphoblastic leukemia, and 1.05 (95% CI: 0.68, 1.61) for CNS tumors. Conclusions: We did not find evidence that domestic radon exposure is associated with childhood cancer, despite relatively high radon levels in Switzerland. Citation: Hauri D, Spycher B, Huss A, Zimmermann F, Grotzer M, von der Weid N, Weber D, Spoerri A, Kuehni C, Röösli M, for the Swiss National Cohort and the Swiss Paediatric Oncology Group (SPOG). 2013. Domestic radon exposure and risk of childhood cancer: a prospective census-based cohort study. Environ Health Perspect 121:1239–1244; http://dx.doi.org/10

  9. Development of calibration facility for radon and its progenies at NIM (China).

    PubMed

    Liang, J C; Zheng, P H; Yang, Z J; Liu, H R; Zhang, M; Li, Z S; Zhang, L; Guo, Q J

    2015-11-01

    Accurate measurement of radon and its progenies is the basis to control the radon dose and reduce the risk of lung cancer caused. The precise calibration of measuring instrument is an important part of the quality control of measurements of the concentration of radon and radon progenies. To establish Chinese national standards and realise reliable calibrations of measuring instrument for radon and its progenies, a radon chamber with regulation capability of environmental parameters, aerosol and radon concentrations was designed and constructed at National Institute of Metrology (NIM). The chamber has a total volume of ∼20 m(3) including an exposure volume of 12.44 m(3). The radon concentration can be controlled from 12 Bq m(-3) to the maximum of 232 kBq m(-3). The regulation range of temperature, relative humidity and aerosol are 0.66 -44.39°C, 16.4 -95 %RH and 10(2) -10(6) cm(-3), respectively. The main advantages of the NIM radon chamber with respect to maintaining a stable concentration and equilibrium factor of radon progenies in a wide range through automatic regulation and control of radon and aerosol are described.

  10. Risk of lung cancer from radon exposure: contribution of recently published studies of uranium miners.

    PubMed

    Tirmarche, M; Harrison, J; Laurier, D; Blanchardon, E; Paquet, F; Marsh, J

    2012-01-01

    The International Commission on Radiological Protection (ICRP) recently estimated the risk of lung cancer associated with radon exposure, and a statement was issued in ICRP Publication 115. This was based on recent epidemiological studies and the results from a joint analysis of cohorts of Czech, French, and German uranium miners, and indicated that the excess relative risk of lung cancer per unit of exposure should be expressed with consideration of chronic exposure over more than 10 years, by modelling time since median exposure, age attained or age at exposure, and taking in account, if possible, interaction between radon and tobacco. The lifetime excess absolute risk (LEAR) calculated from occupational exposure studies is close to 5 × 10(-4) per working level month (WLM) (14 × 10(-5) per hmJ/m(3)). LEAR values estimated using risk models derived from both miners and domestic exposure studies are in good agreement after accounting for factors such as sex, attained age, and exposure scenario. A sensitivity analysis highlighted the high dependence of background mortality rates on LEAR estimates. Using lung cancer rates among Euro-American males instead of the ICRP reference rates (males and females, and Euro-American and Asian populations), the estimated LEAR is close to 7 × 10(-4) per WLM (20 × 10(-5) per hm J/m(3)). Copyright © 2012. Published by Elsevier Ltd.

  11. Residential radon exposure and risk of incident hematologic malignancies in the Cancer Prevention Study-II Nutrition Cohort.

    PubMed

    Teras, Lauren R; Diver, W Ryan; Turner, Michelle C; Krewski, Daniel; Sahar, Liora; Ward, Elizabeth; Gapstur, Susan M

    2016-07-01

    Dosimetric models show that radon, an established cause of lung cancer, delivers a non-negligible dose of alpha radiation to the bone marrow, as well as to lymphocytes in the tracheobronchial epithelium, and therefore could be related to risk of hematologic cancers. Studies of radon and hematologic cancer risk, however, have produced inconsistent results. To date there is no published prospective, population-based study of residential radon exposure and hematologic malignancy incidence. We used data from the American Cancer Society Cancer Prevention Study-II Nutrition Cohort established in 1992, to examine the association between county-level residential radon exposure and risk of hematologic cancer. The analytic cohort included 140,652 participants (66,572 men, 74,080 women) among which 3019 incident hematologic cancer cases (1711 men, 1308 women) were identified during 19 years of follow-up. Cox proportional hazard regression was used to calculate multivariable-adjusted hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for radon exposure and hematologic cancer risk. Women living in counties with the highest mean radon concentrations (>148Bq/m(3)) had a statistically significant higher risk of hematologic cancer compared to those living in counties with the lowest (<74Bq/m(3)) radon levels (HR=1.63, 95% CI:1.23-2.18), and there was evidence of a dose-response relationship (HRcontinuous=1.38, 95% CI:1.15-1.65 per 100Bq/m(3); p-trend=0.001). There was no association between county-level radon and hematologic cancer risk among men. The findings of this large, prospective study suggest residential radon may be a risk factor for lymphoid malignancies among women. Further study is needed to confirm these findings. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Intercomparison of active and passive instruments for radon and radon progeny in North America

    SciTech Connect

    George, A.C.; Tu, Keng-Wu; Knutson, E.O.

    1995-02-01

    An intercomparison exercise for radon and radon progeny instruments and methods was held at the Environmental Measurements Laboratory (EML) from April 22--May 2, 1994. The exercise was conducted in the new EML radon test and calibration facility in which conditions of exposure are very well controlled. The detection systems of the intercompared instruments consisted of. (1) pulse ionization chambers, (2) electret ionization chambers, (3) scintillation detectors, (4) alpha particle spectrometers with silicon diodes, surface barrier or diffused junction detectors, (5) registration of nuclear tracks in solid-state materials, and (6) activated carbon collectors counted by gamma-ray spectrometry or by alpha- and beta-liquid scintillation counting. 23 private firms, government laboratories and universities participated with a 165 passive integrating devices consisting of: Activated carbon collectors, nuclear alpha track detectors and electret ionization chambers, and 11 active and passive continuous radon monitors. Five portable integrating and continuous instruments were intercompared for radon progeny. Forty grab samples for radon progeny were taken by five groups that participated in person to test and evaluate their primary instruments and methods that measure individual radon progeny and the potential alpha energy concentration (PAEC) in indoor air. Results indicate that more than 80% of the measurements for radon performed with a variety of instruments, are within {plus_minus}10% of actual value. The majority of the instruments that measure individual radon progeny and the PAEC gave results that are in good agreement with the EML reference value. Radon progeny measurements made with continuous and integrating instruments are satisfactory with room for improvement.

  13. A study of airborne radon levels in Paarl houses (South Africa) and associated source terms, using electret ion chambers and gamma-ray spectrometry.

    PubMed

    Lindsay, R; Newman, R T; Speelman, W J

    2008-11-01

    Indoor radon ((222)Rn) concentrations were measured in Paarl homes by means of electret ion chambers. The concentrations varied between 28 and 465 Bq m(-3). The average values (Bq m(-3)) found in houses on the west and east side of the Berg River, which bisects Paarl, were 132 (+/-11) and 37 (+/-3), respectively. Radiometric analyses of soils show that the mean (226)Ra activity concentration is three times higher on the west than on the east side of the Berg River.

  14. Radon hazards, geology, and exposure of cave users: a case study and some theoretical perspectives.

    PubMed

    Gillmore, G K; Sperrin, M; Phillips, P; Denman, A

    2000-07-01

    The concerns over the risks to human health from radon in underground caves are poorly documented, unlike in workplace or domestic environments where exposures are relatively well known. In U.K. caves, radon has been identified as occurring at elevated levels; but with the exception of major show caves, its impact and risk to the many groups who use the caves have thus far received inadequate attention. This paper presents a survey performed in a relatively "low-risk" geographical area of the United Kingdom and quantifies the risk of exposure in this cave environment. Radon levels up to 12,552 Bq m(-3) were measured: Such concentrations are very high but are likely to underestimate the levels in many other parts of the cave system, for reasons associated with cave architecture and meteorology. This study confirms previous workers' conclusions that long-term users of deep caves, as opposed to rock shelters, are at risk. Annual doses to certain groups of cave users have been calculated to be as high as 120 mSv, a very high value. The study also demonstrates that there is variation both within and between caves as a result of subtleties of the bedrock geology, fault patterns, and weathering. This paper sets out a theoretical model.

  15. Risk of lung cancer associated with residential radon exposure in south-west England: a case-control study.

    PubMed Central

    Darby, S.; Whitley, E.; Silcocks, P.; Thakrar, B.; Green, M.; Lomas, P.; Miles, J.; Reeves, G.; Fearn, T.; Doll, R.

    1998-01-01

    Studies of underground miners occupationally exposed to radon have consistently demonstrated an increased risk of lung cancer in both smokers and non-smokers. Radon exposure also occurs elsewhere, especially in houses, and estimates based on the findings for miners suggest that residential radon is responsible for about one in 20 lung cancers in the UK, most being caused in combination with smoking. These calculations depend, however, on several assumptions and more direct evidence on the magnitude of the risk is needed. To obtain such evidence, a case-control study was carried out in south-west England in which 982 subjects with lung cancer and 3185 control subjects were interviewed. In addition, radon concentrations were measured at the addresses at which subjects had lived during the 30-year period ending 5 years before the interview. Lung cancer risk was examined in relation to residential radon concentration after taking into account the length of time that subjects had lived at each address and adjusting for age, sex, smoking status, county of residence and social class. The relative risk of lung cancer increased by 0.08 (95% CI -0.03, 0.20) per 100 Bq m(-3) increase in the observed time-weighted residential radon concentration. When the analysis was restricted to the 484 subjects with lung cancer and the 1637 control subjects with radon measurements available for the entire 30-year period of interest, the corresponding increase was somewhat higher at 0.14 per 100 Bq m(-3) (95% CI 0.01, 0.29), although the difference between this group and the remaining subjects was not statistically significant. When the analysis was repeated taking into account uncertainties in the assessment of radon exposure, the estimated increases in relative risk per 100 Bq m(-3) were larger, at 0.12 (95% CI -0.05, 0.33) when all subjects were included and 0.24 (95% CI -0.01, 0.56) when limited to subjects with radon measurements available for all 30 years. These results are consistent

  16. Lung cancer risk and radon exposure in a cohort of iron ore miners in Malmberget, Sweden.

    PubMed

    Jonsson, Håkan; Bergdahl, Ingvar A; Akerblom, Gustav; Eriksson, Kåre; Andersson, Kurt; Kågström, Leif; Järvholm, Bengt; Damber, Lena

    2010-08-01

    Lung cancer caused by radon in miners is a well-known risk. However, the risk estimates vary between studies and between mines. We have studied the dose response-relationship in a Swedish iron ore mine where two other studies have previously reached different risk estimates. As this mine has relatively low radon levels, the results are highly relevant for risk estimation in non-uranium underground mines. A new cohort of 5486 male workers employed from 1923 to 1996 was established. Cumulative radon exposures were assessed based on a large number of measurements, including reconstructions of historical conditions. 122 lung cancer cases occurred during the follow-up period of 1958-2000. The average cumulative exposure in underground workers was 32 kBq year/m(3) (65 working level months (WLM)), experienced over 14.6 years. The excess RR (ERR) per kBq year/m(3) was 0.046 (95% CI 0.015 to 0.077; 0.022 ERR/WLM). Confounding by quartz may affect these results but appears to account only for 10-20% of the risk. The results for squamous cell and small cell lung cancer were 0.049 and 0.072, respectively. However, no increased risk was observed for adenocarcinoma (0.000 ERR per kBq year/m(3), 95% CI -0.017 to 0.017). Our overall risk estimate is about half of that found in the first Malmberget study but twice that found in the same cohort in the previously published pooled analysis. Radon did not increase the risk for adenocarcinoma in the lung.

  17. EPA Urges Home Radon Testing/Protect Your Family from Lung Cancer Caused by Exposure to Radon in Your Home

    EPA Pesticide Factsheets

    WASHINGTON - In recognizing January as National Radon Action Month, EPA encourages Americans around the country to test their homes for this naturally occurring radioactive gas and make 2015 a healthier, safer new year.

  18. What Is Radon?

    MedlinePlus

    ... materials may contribute significantly to radon exposure. Some granite countertops may expose people to different levels of ... experts agree that while a small portion of granite countertops might give off increased levels of radon, ...

  19. Radon and Cancer

    MedlinePlus

    ... Cancer Kidney (Renal Cell) Cancer Leukemia Liver Cancer Lung Cancer Lymphoma Pancreatic Cancer Prostate Cancer Skin Cancer Thyroid ... does radon cause cancer? How many people develop lung cancer because of exposure to radon? How did scientists ...

  20. Therapeutic effect of bilastine in Japanese cedar pollinosis using an artificial exposure chamber (OHIO Chamber).

    PubMed

    Hashiguchi, Kazuhiro; Wakabayashi, Ken-Ichiro; Togawa, Michinori; Saito, Akihiro; Okubo, Kimihiro

    2017-01-01

    Environmental exposure chambers have been used to expose subjects to aeroallergens to investigate the efficacy of prophylactic treatment with symptomatic agents in Japan. We first examined the therapeutic effect of bilastine (BIL), a novel non-sedative second-generation H1-antihistamine, in subjects with Japanese cedar pollinosis using an artificial exposure chamber (OHIO Chamber). This was a randomized, double-blind, four-way crossover, placebo- and active-controlled phase II study (trial registration number JapicCTI-132213). Subjects were exposed to cedar pollen (8000 grains/m(3)) for 2 h on Day -1 and 4 h each on Day 1 and 2. BIL 10 or 20 mg, placebo, or fexofenadine hydrochloride (FEX) 60 mg was administered orally 1 h after the start of pollen exposure on Day 1. Placebo or FEX was administered 12 h after the first dosing. The primary efficacy endpoint was the sum of total nasal symptom score (TNSS) from 0 to 3 h after the Day 1 dosing. We enrolled 136 subjects and the sum of TNSS on Day 1 of the three active treatments was significantly lower than that of placebo and was maintained up to 26 h after the first dosing (Day 2). The sum of TNSS or sneezing score on Day 1 after BIL 20 mg was more significantly decreased than after FEX. Moreover, BIL showed a faster onset of action than FEX. We demonstrated the efficacy, rapid onset, and long duration of action of BIL in subjects with Japanese cedar pollinosis exposed to cedar pollen using the OHIO Chamber. Copyright © 2016 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

  1. Measurement of Radon, Thoron, Isotopic Uranium and Thorium to Determine Occupational and Environmental Exposure and Risk at Fernald Feed Material Production Center

    SciTech Connect

    Naomi H. Harley, Ph.D.

    2004-07-01

    To develop a new and novel area and personal radon/thoron detector for both radon isotopes to better measure the exposure to low airborne concentrations of these gases at Fernald. These measurements are to be used to determine atmospheric dispersion and exposure to radon and thoron prior to and during retrieval and removal of the 4000 Ci of radium in the two silos at Fernald.

  2. Radon Exposure, IL-6 Promoter Variants, and Lung Squamous Cell Carcinoma in Former Uranium Miners

    DOE PAGES

    Leng, Shuguang; Thomas, Cynthia L.; Snider, Amanda M.; ...

    2015-09-15

    Background: High radon exposure is a risk factor for squamous cell carcinoma, a major lung cancer histology observed in former uranium miners. Radon exposure can cause oxidative stress, leading to pulmonary inflammation. Interleukin-6 (IL-6) is a pro-carcinogenic inflammatory cytokine that plays a pivotal role in lung cancer development. Objectives: We assessed whether single nucleotide polymorphisms (SNPs) in the IL6 promoter are associated with lung cancer in former uranium miners with high occupational exposure to radon gas. Methods: Genetic associations were assessed in a case–control study of former uranium miners (242 cases and 336 controls). A replication study was performed usingmore » data from the Gene Environment Association Studies (GENEVA) Genome Wide Association Study (GWAS) of Lung Cancer and Smoking. Functional relevance of the SNPs was characterized using in vitro approaches. Results: We found that rs1800797 was associated with squamous cell carcinoma in miners and with a shorter time between the midpoint of the period of substantial exposure and diagnosis among the cases. Furthermore, rs1800797 was also associated with lung cancer among never smokers in the GENEVA dataset. Functional studies identified that the risk allele was associated with increased basal IL-6 mRNA level and greater promoter activity. Furthermore, fibroblasts with the risk allele showed greater induction of IL-6 secretion by hydrogen peroxide or benzo[a]pyrene diolepoxide treatments. Conclusions: An IL6 promoter variant was associated with lung cancer in uranium miners and never smokers in two external study populations. Lastly, the associations are strongly supported by the functional relevance that the IL6 promoter SNP affects basal expression and carcinogen-induced IL-6 secretion« less

  3. Radon Exposure, IL-6 Promoter Variants, and Lung Squamous Cell Carcinoma in Former Uranium Miners

    SciTech Connect

    Leng, Shuguang; Thomas, Cynthia L.; Snider, Amanda M.; Picchi, Maria A.; Chen, Wenshu; Willis, Derall G.; Carr, Teara G.; Krzeminski, Jacek; Desai, Dhimant; Shantu, Amin; Lin, Yong; Jacobson, Marty R.; Belinsky, Steven A.

    2015-09-15

    Background: High radon exposure is a risk factor for squamous cell carcinoma, a major lung cancer histology observed in former uranium miners. Radon exposure can cause oxidative stress, leading to pulmonary inflammation. Interleukin-6 (IL-6) is a pro-carcinogenic inflammatory cytokine that plays a pivotal role in lung cancer development. Objectives: We assessed whether single nucleotide polymorphisms (SNPs) in the IL6 promoter are associated with lung cancer in former uranium miners with high occupational exposure to radon gas. Methods: Genetic associations were assessed in a case–control study of former uranium miners (242 cases and 336 controls). A replication study was performed using data from the Gene Environment Association Studies (GENEVA) Genome Wide Association Study (GWAS) of Lung Cancer and Smoking. Functional relevance of the SNPs was characterized using in vitro approaches. Results: We found that rs1800797 was associated with squamous cell carcinoma in miners and with a shorter time between the midpoint of the period of substantial exposure and diagnosis among the cases. Furthermore, rs1800797 was also associated with lung cancer among never smokers in the GENEVA dataset. Functional studies identified that the risk allele was associated with increased basal IL-6 mRNA level and greater promoter activity. Furthermore, fibroblasts with the risk allele showed greater induction of IL-6 secretion by hydrogen peroxide or benzo[a]pyrene diolepoxide treatments. Conclusions: An IL6 promoter variant was associated with lung cancer in uranium miners and never smokers in two external study populations. Lastly, the associations are strongly supported by the functional relevance that the IL6 promoter SNP affects basal expression and carcinogen-induced IL-6 secretion

  4. Biology Based Lung Cancer Model for Chronic Low Radon Exposures

    SciTech Connect

    Truta-Popa, Lucia-Adina; Hofmann, Werner; Fakir, Hatim; Cosma, Constantin

    2008-08-07

    Low dose effects of alpha particles at the tissue level are characterized by the interaction of single alpha particles, affecting only a small fraction of the cells within that tissue. Alpha particle intersections of bronchial target cells during a given exposure period were simulated by an initiation-promotion model, formulated in terms of cellular hits within the cycle time of the cell (dose-rate) and then integrated over the whole exposure period (dose). For a given average number of cellular hits during the lifetime of bronchial cells, the actual number of single and multiple hits was selected from a Poisson distribution. While oncogenic transformation is interpreted as the primary initiation step, stimulated mitosis by killing adjacent cells is assumed to be the primary radiological promotion event. Analytical initiation and promotion functions were derived from experimental in vitro data on oncogenic transformation and cellular survival.To investigate the shape of the lung cancer risk function at chronic, low level exposures in more detail, additional biological factors describing the tissue response and operating specifically at low doses were incorporated into the initiation-promotion model. These mechanisms modifying the initial response at the cellular level were: adaptive response, genomic instability, induction of apoptosis by surrounding cells, and detrimental as well as protective bystander mechanisms. To quantify the effects of these mechanisms as functions of dose, analytical functions were derived from the experimental evidence presently available. Predictions of lung cancer risk, including these mechanisms, exhibit a distinct sublinear dose-response relationship at low exposures, particularly for very low exposure rates.

  5. Biology Based Lung Cancer Model for Chronic Low Radon Exposures

    NASA Astrophysics Data System (ADS)

    TruÅ£ǎ-Popa, Lucia-Adina; Hofmann, Werner; Fakir, Hatim; Cosma, Constantin

    2008-08-01

    Low dose effects of alpha particles at the tissue level are characterized by the interaction of single alpha particles, affecting only a small fraction of the cells within that tissue. Alpha particle intersections of bronchial target cells during a given exposure period were simulated by an initiation-promotion model, formulated in terms of cellular hits within the cycle time of the cell (dose-rate) and then integrated over the whole exposure period (dose). For a given average number of cellular hits during the lifetime of bronchial cells, the actual number of single and multiple hits was selected from a Poisson distribution. While oncogenic transformation is interpreted as the primary initiation step, stimulated mitosis by killing adjacent cells is assumed to be the primary radiological promotion event. Analytical initiation and promotion functions were derived from experimental in vitro data on oncogenic transformation and cellular survival. To investigate the shape of the lung cancer risk function at chronic, low level exposures in more detail, additional biological factors describing the tissue response and operating specifically at low doses were incorporated into the initiation-promotion model. These mechanisms modifying the initial response at the cellular level were: adaptive response, genomic instability, induction of apoptosis by surrounding cells, and detrimental as well as protective bystander mechanisms. To quantify the effects of these mechanisms as functions of dose, analytical functions were derived from the experimental evidence presently available. Predictions of lung cancer risk, including these mechanisms, exhibit a distinct sublinear dose-response relationship at low exposures, particularly for very low exposure rates.

  6. Radon Exposure, IL-6 Promoter Variants, and Lung Squamous Cell Carcinoma in Former Uranium Miners

    PubMed Central

    Leng, Shuguang; Thomas, Cynthia L.; Snider, Amanda M.; Picchi, Maria A.; Chen, Wenshu; Willis, Derall G.; Carr, Teara G.; Krzeminski, Jacek; Desai, Dhimant; Shantu, Amin; Lin, Yong; Jacobson, Marty R.; Belinsky, Steven A.

    2015-01-01

    Background: High radon exposure is a risk factor for squamous cell carcinoma, a major lung cancer histology observed in former uranium miners. Radon exposure can cause oxidative stress, leading to pulmonary inflammation. Interleukin-6 (IL-6) is a pro-carcinogenic inflammatory cytokine that plays a pivotal role in lung cancer development. Objectives: We assessed whether single nucleotide polymorphisms (SNPs) in the IL6 promoter are associated with lung cancer in former uranium miners with high occupational exposure to radon gas. Methods: Genetic associations were assessed in a case–control study of former uranium miners (242 cases and 336 controls). A replication study was performed using data from the Gene Environment Association Studies (GENEVA) Genome Wide Association Study (GWAS) of Lung Cancer and Smoking. Functional relevance of the SNPs was characterized using in vitro approaches. Results: We found that rs1800797 was associated with squamous cell carcinoma in miners and with a shorter time between the midpoint of the period of substantial exposure and diagnosis among the cases. Furthermore, rs1800797 was also associated with lung cancer among never smokers in the GENEVA dataset. Functional studies identified that the risk allele was associated with increased basal IL-6 mRNA level and greater promoter activity. Furthermore, fibroblasts with the risk allele showed greater induction of IL-6 secretion by hydrogen peroxide or benzo[a]pyrene diolepoxide treatments. Conclusions: An IL6 promoter variant was associated with lung cancer in uranium miners and never smokers in two external study populations. The associations are strongly supported by the functional relevance that the IL6 promoter SNP affects basal expression and carcinogen-induced IL-6 secretion. Citation: Leng S, Thomas CL, Snider AM, Picchi MA, Chen W, Willis DG, Carr TG, Krzeminski J, Desai D, Shantu A, Lin Y, Jacobson MR, Belinsky SA. 2016. Radon exposure, IL-6 promoter variants, and lung squamous

  7. Influence of environmental changes on continuous radon monitors. Results of a Spanish intercomparison exercise.

    PubMed

    Vargas, A; Ortega, X

    2006-01-01

    The first Spanish intercomparison exercise for continuous radon monitors was carried out with the participation of nine monitoring systems from eight laboratories. The exposures were carried out in the radon and thoron chambers at the Institute of Energy Techniques (INTE) of the Technical University of Catalonia (UPC), which is considered to be the Spanish reference chamber. The monitors were exposed to three different temperatures (13, 20 and 30 degrees C), relative humidities (30, 45 and 80%) and radon concentrations (450, 2000 and 9000 Bq m(-3)). Exposures in the thoron chamber were carried out at concentrations of approximately 450 Bq m(-3). The response of the ionisation chambers and scintillation monitors was acceptable. However, the response of monitors based on electrostatic collection was found to be influenced by external climatic conditions. Moreover, all radon monitors were sensitive to thoron concentration, which was especially significant for scintillation monitors.

  8. Lung Cancer Attributable to Indoor Radon Exposure in France: Impact of the Risk Models and Uncertainty Analysis

    PubMed Central

    Catelinois, Olivier; Rogel, Agnès; Laurier, Dominique; Billon, Solenne; Hemon, Denis; Verger, Pierre; Tirmarche, Margot

    2006-01-01

    Objective The inhalation of radon, a well-established human carcinogen, is the principal—and omnipresent—source of radioactivity exposure for the general population of most countries. Scientists have thus sought to assess the lung cancer risk associated with indoor radon. Our aim here is to assess this risk in France, using all available epidemiologic results and performing an uncertainty analysis. Methods We examined the exposure–response relations derived from cohorts of miners and from joint analyses of residential case-control studies and considered the interaction between radon and tobacco. The exposure data come from measurement campaigns conducted since the beginning of the 1980s by the Institute for Radiation Protection and Nuclear Safety and the Directorate-General of Health in France. We quantified the uncertainties associated with risk coefficients and exposures and calculated their impact on risk estimates. Results The estimated number of lung cancer deaths attributable to indoor radon exposure ranges from 543 [90% uncertainty interval (UI), 75–1,097] to 3,108 (90% UI, 2,996–3,221), depending on the model considered. This calculation suggests that from 2.2% (90% UI, 0.3–4.4) to 12.4% (90% UI, 11.9–12.8) of these deaths in France may be attributable to indoor radon. Discussion In this original work we used different exposure–response relations from several epidemiologic studies and found that regardless of the relation chosen, the number of lung cancer deaths attributable to indoor radon appears relatively stable. Smokers can reduce their risk not only by reducing their indoor radon concentration but also by giving up smoking. PMID:16966089

  9. Efficiency Analysis and Comparison of Different Radon Progeny Measurement Methods

    PubMed Central

    Zhang, Lei

    2013-01-01

    Radon exposure to the public contributes more than half of all the radiation doses caused by natural radiation; accurate measurement of radon progeny is quite essential for the dose evaluation of radon exposure in environment. For the purpose of establishing a radon progeny standard and controlling measurement quality of commercial devices, it is quite important to analyze the efficiency of different measurement methods and determine which would be the most appropriate for radon progeny measurements. Through theoretical analysis and experimental measurement, some commonly used measurement methods were compared in this study and the development trends of those methods were reviewed. Results show that for radon progeny measurement, the spectroscopic analysis method is better than the gross count method, while least-square calculation methods is better than traditional three-count or five-count method. Multiperiod counting of α plus β spectrum as well as using weighted least-square calculation method might be the best choice for accurate measurement on radon progeny in standard radon chamber when calibrating commercial radon progeny monitors. PMID:24385873

  10. Retrospective Determination of Radon Exposure to Glass Using Liquid Scintillation Counting

    NASA Astrophysics Data System (ADS)

    Jones, Rodger Ferguson

    A method is introduced whereby glass samples exposed to known levels of ^{222}Rn are analyzed for ^{210}Pb build-up by liquid scintillation counting. This retrospective radon detector relies on the phenomena of recoil of the decaying nuclide on emission of an alpha -particle into the substrate of the glass. Simple liquid scintillation counting is then used to measure the activity of the ^{210}Pb. The surface of the glass containing the decay products is etched with hydrofluoric acid and then added to a scintillant. The method is useful for exposures up from around 250 PCi.l ^{-1}-years giving a correlation of.97 in a controlled laboratory experiment.

  11. Lung Cancer Attributable to Indoor Radon Exposures in Two Radon—Prone Areas, Ştei (Romania) and Torrelodones (Spain)

    NASA Astrophysics Data System (ADS)

    Dinu, Alexandra; Cosma, Constantin; Sainz, Carlos; Poncela, Luis Santiago Quindós; Vasiliniuc, Ştefan

    2009-05-01

    Radon and radon progeny are present indoors, in houses and others dwellings, representing the most important contribution to dose from natural sources of radiation. Most studies have demonstrated an increased risk of lung cancer at high concentration of radon for both smokers and nonsmokers. For medium and low concentrations which are the typical residential radon levels, recent researches have also demonstrated increased risks of lung cancer for people exposed. The work presents a comparative analysis of the radon exposure data in the two radon—prone areas, Ştei, Transylvania, (Romania), in the near of old Romanian uranium mines and in the granitic area of Torrelodones town, Sierra de Guadarrama (Spain). One important difference between the two studied areas is related to the houses built using uranium waste as construction material in Ştei area. Measurements of indoor radon were performed in 280 dwellings (Romania) and 91 dwellings (Spain) by using nuclear track detectors, CR 39. The highest value measured in Ştei area was 2650 Bqṡm-3. and 366 Bqṡm-3 in the Spanish region. The results are compute with the BEIR VI report estimates using the age-duration model at an exposure rate below 2650 Bqṡm-3. A total of 233 lung cancer deaths were calculated in the Ştei area for a period of 13 years (1994-2006), which is 116.82% higher than observed from the national statistics. In comparison, in Torrelodones area, a number of 276 deaths caused by lung cancer were estimated along a period of 13 years, which is 2.09 times higher than the number observed by authorities. This represents a significantly evidence that elevated risk can strongly be associated with cumulated radon exposure.

  12. Public perceptions of radon risk

    SciTech Connect

    Mainous, A.G. III; Hagen, M.D. )

    1993-03-01

    Since 1984, a significant amount of media attention has focused on health threats from radon gas exposure. Using a probability telephone survey of adults (n = 685), we studied public perceptions of risk from radon exposure versus other environmental health risks. The results indicated that 92% of those individuals who had heard of radon believe radon to be a health risk, although only 4% believe they are currently exposed to high levels of radon gas. Perception of risk from radon was positively related to other perceptions of environmental risks. Younger and less educated individuals were more likely to perceive radon as a health risk. Women were three-and-one-half times as likely as men to perceive risk from radon. However, there was no significant relationship between perceived risk from radon and cigarette smoking. Media attention has apparently led to public awareness of radon hazards, but further attention is needed to improve smokers' awareness of their special risks from radon.

  13. Study of epidemiological risk of lung cancer in Mexico due indoor radon exposure

    NASA Astrophysics Data System (ADS)

    Ángeles, A.; Espinosa, G.

    2014-07-01

    In this work the lifetime relative risks (LRR) of lung cancer due to exposure to indoor 222Rn on the Mexican population is calculated. Cigarette smoking is the number one risk factor for lung cancer (LC), because that, to calculate the number of cases of LC due to exposure to 222Rn is necessary considers the number of cases of LC for smoking cigarette. The lung cancer mortality rates published by the "Secretaría de Salud" (SSA), the mexican population data published by the "Consejo Nacional de Población" (CONAPO), smoking data in the mexican population, published by the "Comisión Nacional Contra las Adicciones" (CONADIC), the "Organización Panamericana de la Salud" (OPS) and indoor 222Rn concentrations in Mexico published in several recent studies are used. To calculate the lifetime relative risks (LRR) for different segments of the Mexican population, firstly the Excess Relative Risk (ERR) is calculated using the method developed by the BEIR VI committee and subsequently modified by the USEPA and published in the report "EPA Assessment of Risks from Radon in Homes". The excess relative risks were then used to calculate the corresponding lifetime relative risks, again using the method developed by the BEIR VI committee. The lifetime relative risks for Mexican male and female eversmokers and Mexican male and female never-smokers were calculated for radon concentrations spanning the range found in recent studies of indoor radon concentrations in Mexico. The lifetime relative risks of lung cancer induced by lifetime exposure to the mexican average indoor radon concentration were estimated to be 1.44 and 1.40 for never-smokers mexican females and males respectively, and 1.19 and 1.17 for ever-smokers Mexican females and males respectively. The Mexican population LRR values obtained in relation to the USA and Canada LRR published values in ever-smokers for both gender are similar with differences less than 4%, in case of never-smokers in relation with Canada

  14. Long-term radon concentrations estimated from 210Po embedded in glass

    USGS Publications Warehouse

    Lively, R.S.; Steck, D.J.

    1993-01-01

    Measured surface-alpha activity on glass exposed in radon chambers and houses has a linear correlation to the integrated radon exposure. Experimental results in chambers and houses have been obtained on glass exposed to radon concentrations between 100 Bq m-3 and 9 MBq m-3 for periods of a few days to several years. Theoretical calculations support the experimental results through a model that predicts the fractions of airborne activity that deposit and become embedded or adsorbed. The combination of measured activity and calculated embedded fraction for a given deposition environment can be applied to most indoor areas and produces a better estimate for lifetime radon exposure than estimates based on short-term indoor radon measurements.

  15. Long-term radon concentrations estimated from 210Po embedded in glass.

    PubMed

    Lively, R S; Steck, D J

    1993-05-01

    Measured surface-alpha activity on glass exposed in radon chambers and houses has a linear correlation to the integrated radon exposure. Experimental results in chambers and houses have been obtained on glass exposed to radon concentrations between 100 Bq m-3 and 9 MBq m-3 for periods of a few days to several years. Theoretical calculations support the experimental results through a model that predicts the fractions of airborne activity that deposit and become embedded or adsorbed. The combination of measured activity and calculated embedded fraction for a given deposition environment can be applied to most indoor areas and produces a better estimate for lifetime radon exposure than estimates based on short-term indoor radon measurements.

  16. In-vivo measurements of Pb-210 to determine cumulative exposure to radon daughters: A pilot study

    SciTech Connect

    Laurer, G.R.; Cohen, N. . Inst. of Environmental Medicine); Stark, A.; Ju, C. . Bureau of Environmental and Occupational Epidemiology)

    1990-10-01

    The feasibility of measuring Pb-210 in vivo in the skulls of those individuals who have resided in homes with above average levels of radon/radon daughters, has now been successfully demonstrated. These values, when incorporated into metabolic models of Pb-210 in the body including other related physical parameters, can be used for the calculation of a realistic estimate of a resident's cumulative exposure to radon and its' decay products. Data are presented for 26 subjects exposed to higher than average concentrations of radon i.e. ranging from 10 to 120 pCi/l, for various periods of time. Their skeletal Pb-210 burdens are compared to measurement results of a population of individuals presumed to have been exposed to values which are more representative of average levels i.e. <1pCi/1. Results of a study to determine the biological retention of Pb-210 in the human skeleton for use in the metabolic model relating skull burdens of this nuclide to cumulative radon/daughter exposure, are also described. At the present time, our measurements, made over a period of 10 years, of an individual with a significant Pb-210 burden, indicate a biological half-time of approximately 57 years and an effective half-life of 16 years. 4 refs., 11 figs.

  17. In-vivo measurements of Pb-210 to determine cumulative exposure to radon daughters: A pilot study. Final report, 1 March, 1990--May 31, 1991

    SciTech Connect

    Laurer, G.R.; Cohen, N.; Stark, A.; Ju, C.

    1991-05-01

    The objective of this study is to demonstrate the feasibility of estimating cumulative exposure of individuals to low concentrations of radon by measuring the amount of Pb-A-10 in their skeletons. This report presents progress to date establishing the validity of an vivo technique to measure skeletal burdens of Pb-210, accumulated from exposure to radon and radon progeny. With the skeletal content of Pb--210 and a model for Pb metabolism, cumulative exposure to radon and its short-lived daughters (radon/daughters) may be calculated for use in deriving a dose-response relationship between lung cancer and exposure to radon/daughters. Data are presented for 29 subjects exposed to ``above-average`` radon concentrations in their homes, showing the correlation between measured Pb--210 burdens, and measured pCi/l and WLM exposure estimates. Their results are compared to measurements of a population of 24 subject`s presumed exposed to average concentrations. Measurements of a Pennsylvania family exposed for a year in a home with an extremely high radon content are also presented. Update of results of an ongoing study of the biological half-time of Pb--210 in man involving measurements, of a retired radiation worker with a 40 year old skeletal burden of Pb-210.

  18. Estimated effective dose rates from radon exposure in workplaces and residences within Los Alamos county in New Mexico

    SciTech Connect

    Whicker, Jeffrey J; Mcnaughton, Michael

    2009-01-01

    Many millions of office workers are exposed to radon while at work and at home. Though there has been a multitude of studies reporting the measurements of radon concentrations and potential lung and effective doses associated with radon and progeny exposure in homes, similar studies on the concentrations and subsequent effective dose rates in the workplace are lacking. The purposes of this study were to measure radon concentrations in office and residential spaces in the same county and explore the radiation dose implications. Sixty-five track-etch detectors were deployed in office spaces and 47 were deployed in residences, all within Los Alamos County, New Mexico, USA. The sampling periods for these measurements were generally about three months. The measured concentrations were then used to calculate and compare effective dose rates resulting from exposure while at work and at home. Results showed that full-time office workers receive on average about nine times greater exposure at home than while in the office (691 mrem yr{sup -1} versus 78 mrem yr{sup -1}). The estimated effective dose rate for a more homebound person was 896 mrem yr{sup -1}. These effective dose rates are contrasted against the 100 mrem yr{sup -1} threshold for regulation of a 'radiological worker' defined in the Department of Energy regulations occupational exposure and the 10 mrem yr{sup -1} air pathway effective public dose limit regulated by the Environmental Protection Agency.

  19. Interpreting short and medium exposure etched-track radon measurements to determine whether an action level could be exceeded.

    PubMed

    Denman, A R; Crockett, R G M; Groves-Kirkby, C J; Phillips, P S

    2016-10-01

    Radon gas is naturally occurring, and can concentrate in the built environment. It is radioactive and high concentration levels within buildings, including homes, have been shown to increase the risk of lung cancer in the occupants. As a result, several methods have been developed to measure radon. The long-term average radon level determines the risk to occupants, but there is always pressure to complete measurements more quickly, particularly when buying and selling the home. For many years, the three-month exposure using etched-track detectors has been the de facto standard, but a decade ago, Phillips et al. (2003), in a DEFRA funded project, evaluated the use of 1-week and 1-month measurements. They found that the measurement methods were accurate, but the challenge lay in the wide variation in radon levels - with diurnal, seasonal, and other patterns due to climatic factors and room use. In the report on this work, and in subsequent papers, the group proposed methodologies for 1-week, 1-month and 3-month measurements and their interpretation. Other work, however, has suggested that 2-week exposures were preferable to 1-week ones. In practice, the radon remediation industry uses a range of exposure times, and further guidance is required to help interpret these results. This paper reviews the data from this study and a subsequent 4-year study of 4 houses, re-analysing the results and extending them to other exposures, particularly for 2-week and 2-month exposures, and provides comprehensive guidance for the use of etched-track detectors, the value and use of Seasonal Correction Factors (SCFs), the uncertainties in short and medium term exposures and the interpretation of results. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Design and use of an exposure chamber for air pollution studies on microarthropods

    SciTech Connect

    Andre, H.M.

    1982-10-01

    An exposure chamber for studying the effects of air pollution on microarthropods is described. The chamber was tested on a corticolous mite, Humerobates rostrolamellatus Grandjean (Acari: Oribatida). In the absence of pollutants, the overall mortality was about 2.5%.

  1. Indoor radon: deadliest pollutant

    SciTech Connect

    Pool, R.

    1988-04-29

    Radon in individual homes may be the greatest source of radiation that people are exposed to during a lifetime. In areas where radon concentrations in homes are high, people may be exposed to more radiation than were the Russian people living in the vicinity of Chernobyl Nuclear Power Plant. Studies indicate that the radon exposure contributes to 5000 to 20,000 deaths per year from lung cancer and that smoking may have a lethal interaction with the radon exposure. One study found an average annual concentration of radon in living spaces of 1.5 picocuries per liter. 7% of U.S. homes were found to have a radon concentration above the 4 picocuries per liter level set by the Environmental Protection Agency, and 1 - 3% of the homes have levels above 8 picocuries. Some ways are described for changing the air pressure in a house so that air is not constantly drawn from the permeable soil where the radon originates.

  2. Symptomatology during hypoxic exposure to flame-retardant chamber atmospheres.

    PubMed

    Knight, D R; Cymerman, A; Devine, J A; Burse, R L; Fulco, C S; Rock, P B; Tappan, D V; Messier, A A; Carhart, H

    1990-01-01

    Hypoxia was studied in 12 men during 63-h exposures to 17 and 13% O2, with the subjects serving as their own controls by repeating the measurements in 21% O2. All test atmospheres were contaminated with 0.9% CO2 to simulate the condition of living aboard submarines. The mean SaO2's were 97-98% in all conditions of 21% O2, 96% in 17% O2 (n.s.), and 92% in 13% O2 (P less than 0.05). The blood concentrations of 2,3-diphosphoglycerate were elevated in 13 and 17% O2 (P less than 0.05). Seventeen percent O2 did not cause significant symptoms of environmental stress; however, 13% O2 caused symptoms of acute mountain sickness in 5 of 12 men. In the last 7 h of exposure to 17% O2, reduction of the barometric pressure to 576 Torr reduced the ambient PO2 to 98 Torr (similar to the PO2 of 13% O2 at normobaric pressure). This induced symptoms of acute mountain sickness in 3 of 11 men. All symptomatology and physiologic changes were reversed during recovery in 21% O2. Monitoring devices indicated the presence of volatile organic contaminants at a mean concentration of 6.1 ppm in the chamber atmosphere. Combustion tests in the occupied chamber showed that flame propagation was retarded by lowering the O2 concentration from 21 to 13-17%. We conclude that men can live comfortably in a normobaric, flame-retardant atmosphere consisting of 17% O2-0.9% CO2-6.1 ppm volatile organic compounds-balance N2.

  3. Radon: Detection and treatment

    SciTech Connect

    Loken, S.; Loken, T. )

    1989-11-01

    Within the last few years, natural radon exposure in non-industrial settings, primarily homes, has become a health concern. Research has demonstrated that many homes throughout the United States have radon concentrations much higher than the legal federal limits set for miners. Thousands of unsuspecting people are being exposed to high levels of radiation. It is estimated that up to 15 percent of lung cancers are caused from radon. This is a significant health risk. With basic knowledge of the current information on radon, a primary health care provider can address patients' radon concerns and make appropriate referrals.

  4. Prediction of residential radon exposure of the whole Swiss population: comparison of model-based predictions with measurement-based predictions.

    PubMed

    Hauri, D D; Huss, A; Zimmermann, F; Kuehni, C E; Röösli, M

    2013-10-01

    Radon plays an important role for human exposure to natural sources of ionizing radiation. The aim of this article is to compare two approaches to estimate mean radon exposure in the Swiss population: model-based predictions at individual level and measurement-based predictions based on measurements aggregated at municipality level. A nationwide model was used to predict radon levels in each household and for each individual based on the corresponding tectonic unit, building age, building type, soil texture, degree of urbanization, and floor. Measurement-based predictions were carried out within a health impact assessment on residential radon and lung cancer. Mean measured radon levels were corrected for the average floor distribution and weighted with population size of each municipality. Model-based predictions yielded a mean radon exposure of the Swiss population of 84.1 Bq/m(3) . Measurement-based predictions yielded an average exposure of 78 Bq/m(3) . This study demonstrates that the model- and the measurement-based predictions provided similar results. The advantage of the measurement-based approach is its simplicity, which is sufficient for assessing exposure distribution in a population. The model-based approach allows predicting radon levels at specific sites, which is needed in an epidemiological study, and the results do not depend on how the measurement sites have been selected.

  5. A macroscopic and microscopic study of radon exposure using Geant4 and MCNPX to estimate dose rates and DNA damage

    NASA Astrophysics Data System (ADS)

    van den Akker, Mary Evelyn

    Radon is considered the second-leading cause of lung cancer after smoking. Epidemiological studies have been conducted in miner cohorts as well as general populations to estimate the risks associated with high and low dose exposures. There are problems with extrapolating risk estimates to low dose exposures, mainly that the dose-response curve at low doses is not well understood. Calculated dosimetric quantities give average energy depositions in an organ or a whole body, but morphological features of an individual can affect these values. As opposed to human phantom models, Computed Tomography (CT) scans provide unique, patient-specific geometries that are valuable in modeling the radiological effects of the short-lived radon progeny sources. Monte Carlo particle transport code Geant4 was used with the CT scan data to model radon inhalation in the main bronchial bifurcation. The equivalent dose rates are near the lower bounds of estimates found in the literature, depending on source volume. To complement the macroscopic study, simulations were run in a small tissue volume in Geant4-DNA toolkit. As an expansion of Geant4 meant to simulate direct physical interactions at the cellular level, the particle track structure of the radon progeny alphas can be analyzed to estimate the damage that can occur in sensitive cellular structures like the DNA molecule. These estimates of DNA double strand breaks are lower than those found in Geant4-DNA studies. Further refinements of the microscopic model are at the cutting edge of nanodosimetry research.

  6. In vivo measurements of lead-210 for assessing cumulative radon exposure in uranium miners

    SciTech Connect

    Guilmette, R.A.; Laurer, G.R.; Lambert, W.E.; Gilliland, F.D.

    1995-12-01

    It has long been recognized that a major contributor to the uncertainty in risk analysis of lung cancer in uranium and other hard rock miners is the estimation of total radon progeny exposure of individual miners under study. These uncertainties arise from the fact that only a limited number of measurements of airborne {sup 222}Rn progeny concentrations were made in the mines during the times that the miners were being exposed, and that dosimeters capable of integrating the Rn progeny exposures of the miners did not exist. Historically, the cumulative exposures for individual uranium and other hard rock miners have been calculated by combining the employee`s work history, which may or may not have included time spent at different jobs within the mines and at different locations within the mines, with whatever periodic measurements of Rn and Rn progeny were available. The amount and quality of the measurement data varied enormously from mine to mine and from population to population. Because the quality of the exposure data collected during the period of active mining in the United STates cannot now be altered substantially, significant improvement in individual miner exposure estimates is only likely to be achieved if a new cumulative exposure metric is developed and implemented. The decay chain of Rn includes the production of {sup 210}Pb, which can accumulate in the skeleton in amounts proportional to the intake of Rn progeny. We hypothesize that the in vivo measurement of {sup 210}Pb in the skulls of miners will provide such a metric. In summary, the primary purpose of this pilot study to demonstrate the feasibility of measuring {sup 210}Pb in the heads of former uranium miners has been accomplished.

  7. Laboratory facility to create reference radon + thoron atmosphere under dynamic exposure conditions.

    PubMed

    Pressyanov, D; Mitev, K; Georgiev, S; Dimitrova, I; Kolev, J

    2017-01-01

    Radon ((222)Rn) and thoron ((220)Rn) levels in the environment are typically subject to significant random and systematic variations. Creation in the laboratory of reproducible and controlled exposure conditions close to that in the real environment can be useful for testing (222)Rn and (220)Rn detectors and for research. In this report the design and performance of a novel laboratory facility with such functionality is presented. The facility allows the exposure of detectors under controlled dynamic as well as static activity concentrations of (222)Rn and (220)Rn (pure and mixed) and temperature. The temperature is measured and regulated within -15 °C ÷ +60 °C by a dedicated programmable thermostat. Different reference activity concentrations in the exposure vessel are made by regulating the flow-rate of the air that flushes (222)Rn/(220)Rn activity from the sources towards the exposure vessel. Reference atmospheres that contain (222)Rn, (220)Rn or a specified ratio of the two can be created. Pilot experiments that demonstrate the feasibility of the approach are presented. They include follow-up of a pre-defined temperature profile (in the range -5 °C ÷ +35 °C), test of the correspondence between planned and measured (222)Rn and (220)Rn activity concentrations, follow-up of a pre-defined dynamic profile of (220)Rn concentrations and test of the possibility to create mixed (220)Rn/(222)Rn atmospheres (experimentally checked for ratio of the activity concentrations from 0.27 to 4.5). The results from the experimental tests are in agreement with the values obtained by the developed theoretical model. The proposed approach can be used to plan and create stationary and dynamic reference exposure conditions that are close to the real exposure regimes in the environment.

  8. Multi-parametric approach towards the assessment of radon and thoron progeny exposures

    SciTech Connect

    Mishra, Rosaline E-mail: rosaline.mishra@gmail.com; Sapra, B. K.; Mayya, Y. S.

    2014-02-15

    Conventionally, the dosimetry is carried out using radon and thoron gas concentration measurements and doses have been assigned using assumed equilibrium factors for the progeny species, which is inadequate pertaining to the variations in equilibrium factors and possibly due to significant thoron. In fact, since the true exposures depend upon the intricate mechanisms of progeny deposition in the lung, therefore an integrated approach for the assessment of progeny is essential. In this context, the recently developed deposition based progeny concentration measurement techniques (DTPS: Direct Thoron progeny sensors and DRPS: Direct Radon progeny sensors) appear to be best suited for radiological risk assessments both among occupational workers and general study populations. DTPS and DRPS consist of aluminized mylar mounted LR115 type passive detectors, which essentially detects the alpha particles emitted from the deposited progeny atoms on the detector surface. It gives direct measure of progeny activity concentrations in air. DTPS has a lower limit of detection limit of 0.1 Bq/m{sup 3} whereas that for DRPS is 1 Bq/m{sup 3}, hence are perfectly suitable for indoor environments. These DTPS and DRPS can be capped with 200-mesh type wire-screen to measure the coarse fraction of the progeny concentration and the corresponding coarse fraction deposition velocities as well as the time integrated fine fraction. DTPS and DRPS can also be lodged in an integrated sampler wherein the wire-mesh and filter-paper are arranged in an array in flow-mode, to measure the fine and coarse fraction concentration separately and simultaneously. The details are further discussed in the paper.

  9. Radon-induced lung cancer deaths may be overestimated due to failure to account for confounding by exposure to diesel engine exhaust in BEIR VI miner studies.

    PubMed

    Cao, Xiaodong; MacNaughton, Piers; Laurent, Jose Cedeno; Allen, Joseph G

    2017-01-01

    EPA reported that radon is the second leading cause of lung cancer in the United States, killing 21,100 people per year. EPA relies on the BEIR VI models, based on an evaluation of radon exposure and lung cancer risk in studies of miners. But these models did not account for co-exposure to diesel exhaust, a known human carcinogen recently classified by IARC. It is probable then that a portion of the lung cancer deaths in the miner cohorts are originally attributable to the exposure to diesel rather than radon. To re-evaluate EPA's radon attributable lung cancer estimates accounting for diesel exposure information in the miner cohorts. We used estimates of historical diesel concentrations, combined with diesel exposure-response functions, to estimate the risks of lung cancer attributable to diesel engine exhaust (DEE) exposure in the miner studies. We re-calculated the fatal lung cancer risk attributable to radon after accounting for risk from diesel and re-estimated the number of U.S. deaths associated with radon in the U.S. using EPA's methodology. Considering the probable confounding with DEE exposure and using the same estimate of baseline mortality from 1989-91 that the EPA currently uses in their calculations, we estimate that radon-induced lung cancer deaths per year are 15,600 (95% CI: 14,300, 17,000)- 19,300 (95% CI: 18,800, 20,000) in the U.S. population, a reduction of 9%-26%. The death estimates would be 12,900-15,900 using 2014 baseline vital statistics. We recommend further research on re-evaluating the health effects of exposure to radon that accounts for new information on diesel exhaust carcinogenicity in BEIR VI models, up-to-date vital statistics and new epidemiological evidence from residential studies.

  10. Radon-induced lung cancer deaths may be overestimated due to failure to account for confounding by exposure to diesel engine exhaust in BEIR VI miner studies

    PubMed Central

    MacNaughton, Piers; Laurent, Jose Cedeno; Allen, Joseph G.

    2017-01-01

    Background EPA reported that radon is the second leading cause of lung cancer in the United States, killing 21,100 people per year. EPA relies on the BEIR VI models, based on an evaluation of radon exposure and lung cancer risk in studies of miners. But these models did not account for co-exposure to diesel exhaust, a known human carcinogen recently classified by IARC. It is probable then that a portion of the lung cancer deaths in the miner cohorts are originally attributable to the exposure to diesel rather than radon. Objective To re-evaluate EPA’s radon attributable lung cancer estimates accounting for diesel exposure information in the miner cohorts. Methods We used estimates of historical diesel concentrations, combined with diesel exposure-response functions, to estimate the risks of lung cancer attributable to diesel engine exhaust (DEE) exposure in the miner studies. We re-calculated the fatal lung cancer risk attributable to radon after accounting for risk from diesel and re-estimated the number of U.S. deaths associated with radon in the U.S. using EPA’s methodology. Results Considering the probable confounding with DEE exposure and using the same estimate of baseline mortality from 1989–91 that the EPA currently uses in their calculations, we estimate that radon-induced lung cancer deaths per year are 15,600 (95% CI: 14,300, 17,000)– 19,300 (95% CI: 18,800, 20,000) in the U.S. population, a reduction of 9%–26%. The death estimates would be 12,900–15,900 using 2014 baseline vital statistics. Conclusions We recommend further research on re-evaluating the health effects of exposure to radon that accounts for new information on diesel exhaust carcinogenicity in BEIR VI models, up-to-date vital statistics and new epidemiological evidence from residential studies. PMID:28886109

  11. Attachment of radon progeny to cigarette-smoke aerosols

    SciTech Connect

    Biermann, A.H.; Sawyer, S.R.

    1995-05-01

    The daughter products of radon gas are now recognized as a significant contributor to radiation exposure to the general public. It is also suspected that a synergistic effect exists with the combination cigarette smoking and radon exposure. We have conducted an experimental investigation to determine the physical nature of radon progeny interactions with cigarette smoke aerosols. The size distributions of the aerosols are characterized and attachment rates of radon progeny to cigarette-smoke aerosols are determined. Both the mainstream and sidestream portions of the smoke aerosol are investigated. Unattached radon progeny are very mobile and, in the presence of aerosols, readily attach to the particle surfaces. In this study, an aerosol chamber is used to contain the radon gas, progeny and aerosol mixture while allowing the attachment process to occur. The rate of attachment is dependent on the size distribution, or diffusion coefficient, of the radon progeny as well as the aerosol size distribution. The size distribution of the radon daughter products is monitored using a graded-screen diffusion battery. The diffusion battery also enables separation of the unattached radon progeny from those attached to the aerosol particles. Analysis of the radon decay products is accomplished using alpha spectrometry. The aerosols of interest are size fractionated with the aid of a differential mobility analyzer and cascade impactor. The measured attachment rates of progeny to the cigarette smoke are compared to those found in similar experiments using an ambient aerosol. The lowest attachment coefficients observed, {approximately}10{sup {minus}6} cm{sup 3}/s, occurred for the ambient aerosol. The sidestream and mainstream smoke aerosols exhibited higher attachment rates in that order. The results compared favorably with theories describing the coagulation process of aerosols.

  12. [Radon risk in healthcare facilities: environmental monitoring and effective dose].

    PubMed

    Cammarota, B; Cascone, Maria Teresa; De Paola, L; Schillirò, F; Del Prete, U

    2009-01-01

    Radon, the second cause of lung cancer after smoking (WHO- IARC), is a natural, radioactive gas, which originates from the soil and pollutes indoor air, especially in closed or underground spaces. The purpose of this study was to determine the concentration of radon gas, its effective dose, and the measurement of microclimatic degrees C; U.R. % and air velocity in non-academic intensive care units of public hospitals in the Naples area. The annual average concentrations of radon gas were detected with EIC type ionization electret chambers, type LLT with exposure over four 3-month periods. The concentrations varied for all health facilities between 186 and 1191 Bq/m3. Overall, the effective dose of exposure to radon gas of 3mSv/a recommended by Italian legislation was never exceeded. The concentration of radon gas showed a decreasing trend starting from the areas below ground level to those on higher floors; such concentrations were also influenced by natural and artificial ventilation of the rooms, building materials used for walls, and by the state of maintenance and improvements of the building (insulation of floors and walls). The data obtained confirmed the increased concentration of radionuclides in the yellow tuff of volcanic origin in the Campania Region and the resulting rate of release of radon gas, whereas the reinforced concrete structure (a hospital located on the hillside), which had the lowest values, proved to provide good insulation against penetration and accumulation of radon gas.

  13. Experimental setup for radon exposure and first diffusion studies using gamma spectroscopy

    NASA Astrophysics Data System (ADS)

    Maier, Andreas; van Beek, Patrick; Hellmund, Johannes; Durante, Marco; Schardt, Dieter; Kraft, Gerhard; Fournier, Claudia

    2015-11-01

    In order to measure the uptake and diffusion of 222Rn in biological material, an exposure chamber was constructed where cell cultures, biological tissues and mice can be exposed to 222Rn-activities similar to therapy conditions. After exposure, the material is transferred to a gamma spectrometer and the decay of 214Pb and 214Bi is analyzed. From the time kinetics of these decays the total amount of the initial 222Rn concentration can be calculated. In this paper the design and construction as well as first test measurements are reported.

  14. USACE FUSRAP Maywood Team Develops a Mechanism to Evaluate Residual Radon Exposure Potential at Vicinity Properties Where Remediation of Accessible Contamination has been Completed

    SciTech Connect

    Winters, M.; Walnicki, S.; Hays, D.

    2008-07-01

    The Maywood FUSRAP Team is obligated, under its approved remedy selection decision document, to demonstrate substantive compliance with New Jersey Administrative Code 7:28- 12(a)2, establishing an indoor limit of three Pico-Curies per liter above background for radon-222 (Rn-222). The Maywood Team explores various avenues for dealing with the radon issue and provides an alternative for demonstrating substantive compliance with the radon remediation standard by answering the question: 'In certain conservative situations, can compliance with the radon standard be demonstrated without performing monitoring?' While monitoring may be the most definitive method for demonstrating compliance, a logical argument can be made that when radiological remediation removes the potential source for Rn-222 above background, monitoring is unnecessary. This position is defended through the use of historical physical radon measurements which illustrate that indoor radon was not a pre-remediation problem, and post-remediation soil sampling data which demonstrate that the source of the potentially elevated Rn- 222 levels have been successfully mitigated. Monitoring recommendations are made for situations where insufficient data exists to make definitive determinations or when un-remediated sources affecting habitable structures remain on a given property. Additional information regarding recommended techniques and references for effective monitoring of indoor radon are included in this paper. This paper may benefit teams that have similar regulatory commitments and/or have need to make assessments of radon exposure potential based upon historical monitoring data and available soils concentration data. (authors)

  15. A Pilot Study to Examine Exposure to Residential Radon in Under-Sampled Census Tracts of DeKalb County, Georgia, in 2015

    PubMed Central

    Stauber, Christine E.; Dai, Dajun; Chan, Sydney R.; Diem, Jeremy E.; Weaver, Scott R.; Rothenberg, Richard

    2017-01-01

    While DeKalb County, Georgia, offers free radon screening for all eligible residents, portions of the county remain relatively under-sampled. This pilot study focused on 10% of the census tracts in the county with the lowest proportion of radon testing; most were in southern DeKalb County. In total, 217 households were recruited and homes were tested for indoor radon concentrations on the lowest livable floor over an eight-week period from March–May 2015. Tract-level characteristics were examined to understand the differences in socio-demographic and economic factors between the pilot study area and the rest of the county. The pilot study tracts had a higher proportion of African Americans compared to the rest of DeKalb County (82% versus 47%). Radon was detected above 11.1 Bq/m3 (0.3 pCi/L) in 73% of the indoor samples and 4% of samples were above 148 Bq/m3 (4 pCi/L). Having a basement was the strongest predictive factor for detectable and hazardous levels of radon. Radon screening can identify problems and spur homeowners to remediate but more research should be done to identify why screening rates vary across the county and how that varies with radon levels in homes to reduce radon exposure. PMID:28327511

  16. A hooded exposure chamber method for semiquantitative latex aeroallergen challenge.

    PubMed

    Kurtz, K M; Hamilton, R G; Schaefer, J A; Adkinson, N F

    2001-01-01

    Allergen challenges are useful in adjudicating discordant clinical histories and skin test responses, serologic test responses, or both, as well as in determining the degree of allergic reactivity. Latex allergen challenges have been developed but have limitations that reduce their usefulness. We sought to develop a novel hooded exposure chamber (HEC) system to allow safe, sensitive, and semiquantitative evaluation of respiratory latex allergy. The HEC system uses an impinger to produce a particle cloud of cornstarch isolated from powdered latex gloves. The particles are air driven into a face shield and hood to simultaneously challenge the subject's conjunctiva, nose, and lungs during 3 minutes of normal tidal breathing. A cloud of respirable latex allergen-associated cornstarch particles (LACs) is consistently produced in the HEC during challenges. Twenty-three subjects with latex allergy (history and positive skin test response, positive serologic test response, or both) and 3 atopic control subjects not allergic to latex (history and negative skin test response, negative serologic test response, or both) were sequentially exposed to air, control cornstarch, and then progressive 2-fold increments of LACs in a single-masked fashion. A positive challenge result was defined as (1) a peak expiratory flow rate decline of 15% or greater from baseline; (2) a peak expiratory flow rate decline of 10% or greater and an increase of either the rhinoconjunctivitis or chest symptom score scale of 3 or more points from baseline; or (3) an increase of either the rhinoconjunctivitis or chest symptom score scale of 6 or more points from baseline. Twenty-two of the 23 subjects with latex allergy reached threshold criteria for a positive challenge at LAC titers of 1:8 or greater, giving a sensitivity of 0.96. Challenge endpoints were moderately corrected with skin test sensitivity (r (s) = -0.55, P =.01) but not with RAST reactivity. None of the 3 control subjects responded to LACs

  17. Radiological risk assessment of environmental radon

    NASA Astrophysics Data System (ADS)

    Khalid, Norafatin; Majid, Amran Ab; Yahaya, Redzuwan; Yasir, Muhammad Samudi

    2013-11-01

    Measurements of radon gas (222Rn) in the environmental are important to assess indoor air quality and to study the potential risk to human health. Generally known that exposure to radon is considered the second leading cause of lung cancer after smoking. The environmental radon concentration depends on the 226Ra concentration, indoor atmosphere, cracking on rocks and building materials. This study was carried out to determine the indoor radon concentration from selected samples of tin tailings (amang) and building materials in an airtight sealed homemade radon chamber. The radiological risk assessment for radon gas was also calculated based on the annual exposure dose, effective dose equivalent, radon exhalation rates and fatal cancer risk. The continuous radon monitor Sun Nuclear model 1029 was used to measure the radon concentration emanates from selected samples for 96 hours. Five types of tin tailings collected from Kampar, Perak and four samples of building materials commonly used in Malaysia dwellings or building constructions were analysed for radon concentration. The indoor radon concentration determined in ilmenite, monazite, struverite, xenotime and zircon samples varies from 219.6 ± 76.8 Bq m-3 to 571.1 ± 251.4 Bq m-3, 101.0 ± 41.0 Bq m-3 to 245.3 ± 100.2 Bq m-3, 53.1 ± 7.5 Bq m-3 to 181.8 ± 9.7 Bq m-3, 256.1 ± 59.3 Bq m-3 to 652.2 ± 222.2 Bq m-3 and 164.5 ± 75.9 Bq m-3 to 653.3 ± 240.0 Bq m-3, respectively. Whereas, in the building materials, the radon concentration from cement brick, red-clay brick, gravel aggregate and cement showed 396.3 ± 194.3 Bq m-3, 192.1 ± 75.4 Bq m-3, 176.1 ± 85.9 Bq m-3 and 28.4 ± 5.7 Bq m-3, respectively. The radon concentration in tin tailings and building materials were found to be much higher in xenotime and cement brick samples than others. All samples in tin tailings were exceeded the action level for radon gas of 148 Bq m-3 proposed by EPA except monazite 0.15 kg, struverite 0.15 kg and 0.25 kg. Whereas

  18. Radiological risk assessment of environmental radon

    SciTech Connect

    Khalid, Norafatin; Majid, Amran Ab; Yahaya, Redzuwan; Yasir, Muhammad Samudi

    2013-11-27

    Measurements of radon gas ({sup 222}Rn) in the environmental are important to assess indoor air quality and to study the potential risk to human health. Generally known that exposure to radon is considered the second leading cause of lung cancer after smoking. The environmental radon concentration depends on the {sup 226}Ra concentration, indoor atmosphere, cracking on rocks and building materials. This study was carried out to determine the indoor radon concentration from selected samples of tin tailings (amang) and building materials in an airtight sealed homemade radon chamber. The radiological risk assessment for radon gas was also calculated based on the annual exposure dose, effective dose equivalent, radon exhalation rates and fatal cancer risk. The continuous radon monitor Sun Nuclear model 1029 was used to measure the radon concentration emanates from selected samples for 96 hours. Five types of tin tailings collected from Kampar, Perak and four samples of building materials commonly used in Malaysia dwellings or building constructions were analysed for radon concentration. The indoor radon concentration determined in ilmenite, monazite, struverite, xenotime and zircon samples varies from 219.6 ± 76.8 Bq m{sup −3} to 571.1 ± 251.4 Bq m{sup −3}, 101.0 ± 41.0 Bq m{sup −3} to 245.3 ± 100.2 Bq m{sup −3}, 53.1 ± 7.5 Bq m{sup −3} to 181.8 ± 9.7 Bq m{sup −3}, 256.1 ± 59.3 Bq m{sup −3} to 652.2 ± 222.2 Bq m{sup −3} and 164.5 ± 75.9 Bq m{sup −3} to 653.3 ± 240.0 Bq m{sup −3}, respectively. Whereas, in the building materials, the radon concentration from cement brick, red-clay brick, gravel aggregate and cement showed 396.3 ± 194.3 Bq m{sup −3}, 192.1 ± 75.4 Bq m{sup −3}, 176.1 ± 85.9 Bq m{sup −3} and 28.4 ± 5.7 Bq m{sup −3}, respectively. The radon concentration in tin tailings and building materials were found to be much higher in xenotime and cement brick samples than others. All samples in tin tailings were exceeded the

  19. The April 1994 and October 1994 radon intercomparisons at EML

    SciTech Connect

    Fisenne, I.M.; George, A.C.; Perry, P.M.; Keller, H.W.

    1995-10-01

    Quality assurance/quality control (QA/QC) are the backbone of many commercial and research processes and programs. QA/QC research tests the state of a functioning system, be it the production of manufactured goods or the ability to make accurate and precise measurements. The quality of the radon measurements in the US have been tested under controlled conditions in semi-annual radon gas intercomparison exercises sponsored by the Environmental Measurements Laboratory (EML) since 1981. The two Calendar Year 1994 radon gas intercomparison exercises were conducted in the EML exposure chamber. Thirty-two groups including US Federal facilities, USDOE contractors, national and state laboratories, universities and foreign institutions participated in these exercises. The majority of the participant`s results were within {+-}10% of the EML value at radon concentrations of 570 and 945 Bq m{sup {minus}3}.

  20. Radon Exposure and the Definition of Low Doses-The Problem of Spatial Dose Distribution.

    PubMed

    Madas, Balázs G

    2016-07-01

    Investigating the health effects of low doses of ionizing radiation is considered to be one of the most important fields in radiological protection research. Although the definition of low dose given by a dose range seems to be clear, it leaves some open questions. For example, the time frame and the target volume in which absorbed dose is measured have to be defined. While dose rate is considered in the current system of radiological protection, the same cancer risk is associated with all exposures, resulting in a given amount of energy absorbed by a single target cell or distributed among all the target cells of a given organ. However, the biological effects and so the health consequences of these extreme exposure scenarios are unlikely to be the same. Due to the heterogeneous deposition of radon progeny within the lungs, heterogeneous radiation exposure becomes a practical issue in radiological protection. While the macroscopic dose is still within the low dose range, local tissue doses on the order of Grays can be reached in the most exposed parts of the bronchial airways. It can be concluded that progress in low dose research needs not only low dose but also high dose experiments where small parts of a biological sample receive doses on the order of Grays, while the average dose over the whole sample remains low. A narrow interpretation of low dose research might exclude investigations with high relevance to radiological protection. Therefore, studies important to radiological protection should be performed in the frame of low dose research even if the applied doses do not fit in the dose range used for the definition of low doses.

  1. Human exposure to indoor radon: a survey in the region of Guarda, Portugal.

    PubMed

    Louro, Alina; Peralta, Luís; Soares, Sandra; Pereira, Alcides; Cunha, Gilda; Belchior, Ana; Ferreira, Luís; Monteiro Gil, Octávia; Louro, Henriqueta; Pinto, Paulo; Rodrigues, António Sebastião; Silva, Maria João; Teles, Pedro

    2013-04-01

    Radon ((222)Rn) is a radioactive gas, abundant in granitic areas, such as the city of Guarda at the northeast of Portugal. This gas is recognised as a carcinogenic agent, being appointed by the World Health Organization as the second leading cause of lung cancer after tobacco smoke. Therefore, the knowledge of radon concentrations inside the houses (where people stay longer) is important from the point of view of radiological protection. The main goal of this study was to assess the radon concentration in an area previously identified with a potentially high level of residential radon. The radon concentration was measured using CR-39 detectors, exposed for a period of 2 months in 185 dwellings in the Guarda region. The radon concentration in studied dwellings, ranged between 75 and 7640 Bq m(-3), with a geometric mean of 640 Bq m(-3) and an arithmetic mean of 1078 Bq m(-3). Based on a local winter-summer radon concentration variation model, these values would correspond to an annual average concentration of 860 Bq m(-3). Several factors contribute to this large dispersion, the main one being the exact location of housing construction in relation to the geochemical nature of the soil and others the predominant building material and ventilation. Based on the obtained results an average annual effective dose of 15 mSv y(-1) is estimated, well above the average previously estimated for Portugal.

  2. Low radon exposure and mortality among Jouac uranium miners: an update of the French cohort (1946-2007).

    PubMed

    Rage, Estelle; Caër-Lorho, Sylvaine; Laurier, Dominique

    2017-09-19

    After the extension of the French cohort of uranium miners with the inclusion of workers employed in the Jouac mines, this article seeks to describe the new Jouac cohort and to estimate mortality risks, as well as to quantify their relation to radon exposure in this extended cohort. The Jouac cohort includes 458 miners hired by the Société des Mines de Jouac between 1957 and 2001. As there is no measurement of radon exposure before 1978 were unavailable, only the post-1977 Jouac cohort (n=314) has been included in the French cohort, creating an extended cohort of 5400 French uranium miners followed up from 1946 to 2007. Mortality analyses computed the standardised mortality ratios (SMR). Excess relative risks (ERR) were assessed using Poisson regression models. No evidence of a significant excess risk of overall mortality (n=66, SMR=0.93; 95% CI = 0.72-1.19) or any specific mortality was observed in the Jouac cohort. In the extended cohort, overall mortality did not increase, but a significant excess of deaths was observed for all cancers (SMR=1.11, 95% CI = 1.03-1.19), lung cancer (SMR=1.32, 95% CI = 1.14-1.51), and kidney cancer (SMR=1.58, 95% CI = 1.01-2.35). Cumulative exposure to radon was 3.9 Working Level Month (WLM) and 35.1 WLM in the post-1977 Jouac and extended cohorts respectively. Cumulative radon exposure was significantly associated with an excess risk of death from lung cancer (ERR/100 WLM = 0.73, 95% CI = 0.32-1.33) and from cerebrovascular diseases (ERR/100 WLM = 0.42 95% CI = 0.04-1.04). In conclusion, the Jouac cohort is still a young cohort and its inclusion leads to slightly modifications compared to previous analyses of for the French cohort. The already known relation between radon exposure and lung cancer death as well as the excess risk for death for cerebrovascular diseases persisted in the extended cohort. © 2017 IOP Publishing Ltd.

  3. Effects of radon mitigation vs smoking cessation in reducing radon-related risk of lung cancer.

    PubMed Central

    Mendez, D; Warner, K E; Courant, P N

    1998-01-01

    OBJECTIVES: The purpose of this paper is to provide smokers with information on the relative benefits of mitigating radon and quitting smoking in reducing radon-related lung cancer risk. METHODS: The standard radon risk model, linked with models characterizing residential radon exposure and patterns of moving to new homes, was used to estimate the risk reduction produced by remediating high-radon homes, quitting smoking, or both. RESULTS: Quitting smoking reduces lung cancer risk from radon more than does reduction of radon exposure itself. CONCLUSIONS: Smokers should understand that, in addition to producing other health benefits, quitting smoking dominates strategies to deal with the problem posed by radon. PMID:9585753

  4. Radon: Is it a problem

    SciTech Connect

    Hart, B.L.; Mettler, F.A.; Harley, N.H. )

    1989-09-01

    Radon gas is a major source of radiation exposure to the general public. Radon-222 is a product of uranium-238, present in varying concentrations in all soils. Radon enters buildings from soil, water, natural gas, and building materials. Its short-lived breakdown products, termed radon daughters, include alpha-emitting solids that can deposit in the lungs. Firm evidence links lung cancer risk in miners with high exposure to radon daughters. The amount of risk associated with the much lower but chronic doses received in buildings is difficult to establish. By some extrapolations, radon daughters may be responsible for a significant number of lung cancer deaths. The existence or extent of synergism with smoking is unresolved. Local conditions can cause high levels of radon in some buildings, and measures that reduce indoor radon are of potential value. 39 references.

  5. Estimation of the indoor radon and the annual effective dose from granite samples

    NASA Astrophysics Data System (ADS)

    Sola, P.; Srinuttrakul, W.; Kewsuwan, P.

    2015-05-01

    Inhalation of radon and thoron daughters increases the risk of lung cancer. The main sources of indoor radon are building materials. The aim of this research is to estimate the indoor radon and the annual effective dose from the building materials. Eighteen granite samples bought from the markets in Thailand were measured using an ionization chamber (ATMOS 12 DPX) for the radon concentration in air. Radon exhalation rates were calculated from the radon concentration in chamber. The indoor radon from the granite samples ranged from 10.04 to 55.32 Bq·m-2·h-1 with an average value of 20.30 Bq·m-2·h-1 and the annual effective dose ranged from 0.25 to 1.39 mSv·y-1 with an average value of 0.48 mSv·y-1. The results showed that the annual effective doses of three granite samples were higher than the annual exposure limit for the general public (1 mSv·y-1) recommended by the International Commission on Radiological Protection (ICRP). In addition, the relationship between the colours and radon exhalation rates of granite samples was also explained.

  6. Comparative survey of outdoor, residential and workplace radon concentrations.

    PubMed

    Barros, Nirmalla; Field, Dan W; Steck, Daniel J; Field, R William

    2015-02-01

    This study investigated radon concentrations in above-ground (i.e. first floor) workplace in Missouri and compared them with above-ground radon concentrations in nearby homes and outdoor locations. This study also examined the potential utility of using home and outdoor radon concentrations to predict the radon concentration at a nearby workplace (e.g. county agencies and schools). Even though workplace radon concentrations were not statistically different from home radon concentrations, the radon concentration at a particular home, or outdoor location, was a poor predictor of the radon concentration at a nearby workplace. Overall, 9.6 and 9.9 % of homes and workplace, respectively, exhibited radon concentrations of ≥148 Bq m(-3). Because of the percentage of workplace with elevated radon concentrations, the results suggest that additional surveys of workplace radon concentrations are needed, especially in areas of high radon potential, to assess the contribution of workplace radon exposure to an individual's overall radon exposure.

  7. Variation of soil radon concentrations in southern Ontario.

    PubMed

    Chen, J; Ly, J; Bergman, L; Wierdsma, J; Klassen, R A

    2008-01-01

    Radon has been identified as the second leading cause of lung cancer after tobacco smoking. Information on indoor radon concentrations is required to assess the lung cancer burden due to radon exposure. However, radon data in highly populated southern Ontario are very limited. Since radon in soil is believed to be the main source of radon in homes, measurements of soil gas radon concentrations can be used to estimate variations in radon potential of indoor environments. This study reports a transect survey of natural background variation in soil radon levels across southern Ontario. The results indicate that radon risk could be high in some areas of southern Ontario.

  8. Radon: The Silent Danger.

    ERIC Educational Resources Information Center

    Stoffel, Jennifer

    1989-01-01

    This article discusses the public health dangers associated with radon exposure in homes and schools. In addition, testing and corrective efforts by federal and state agencies are discussed. A map indicating areas in the U.S. with potentially high radon levels is included. (IAH)

  9. Radon: The Silent Danger.

    ERIC Educational Resources Information Center

    Stoffel, Jennifer

    1989-01-01

    This article discusses the public health dangers associated with radon exposure in homes and schools. In addition, testing and corrective efforts by federal and state agencies are discussed. A map indicating areas in the U.S. with potentially high radon levels is included. (IAH)

  10. alpha-Radiation dose at bronchial bifurcations of smokers from indoor exposure to radon progeny.

    PubMed Central

    Martell, E A

    1983-01-01

    Synergistic interactions of indoor radon progeny with the cigarette smoking process have been evaluated experimentally. Smoking enhances the air concentration of submicron particles and attached radon decay products. Fractionation in burning cigarettes gives rise to the association of radon progeny with large particles in mainstream cigarette smoke, which are selectively deposited in "hot spots" at bronchial bifurcations. Because smoke tars are resistant to dissolution in lung fluid, attached radon progeny undergo substantial radioactive decay at bifurcations before clearance. Radon progeny inhaled during normal breathing between cigarettes make an even larger contribution to the alpha-radiation dose at bifurcations. Progressive chemical and radiation damage to the epithelium at bifurcations gives rise to prolonged retention of insoluble 210Pb-enriched smoke particles produced by tobacco trichome combustion. The high incidence of lung cancer in cigarette smokers is attributed to the cumulative alpha-radiation dose at bifurcations from indoor radon and thoron progeny--218Po, 214Po, 212Po, and 212Bi--plus that from 210Po in 210Pb-enriched smoke particles. It is estimated that a carcinogenic alpha-radiation dose of 80-100 rads (1 rad = 0.01 J/kg = 0.01 Gy) is delivered to approximately equal to 10(7) cells (approximately equal to 10(6) cells at individual bifurcations) of most smokers who die of lung cancer. PMID:6572389

  11. Comparison of active and passive methods for radon exhalation from a high-exposure building material.

    PubMed

    Abbasi, A; Mirekhtiary, F

    2013-12-01

    The radon exhalation rates and radon concentrations in granite stones used in Iran were measured by means of a high-resolution high purity Germanium gamma-spectroscopy system (passive method) and an AlphaGUARD model PQ 2000 (active method). For standard rooms (4.0 × 5.0 m area × 2.8 height) where ground and walls have been covered by granite stones, the radon concentration and the radon exhalation rate by two methods were calculated. The activity concentrations of (226)Ra in the selected granite samples ranged from 3.8 to 94.2 Bq kg(-1). The radon exhalation rate from the calculation of the (226)Ra activity concentration was obtained. The radon exhalation rates were 1.31-7.86 Bq m(-2)h(-1). The direction measurements using an AlphaGUARD were from 218 to 1306 Bq m(-3) with a mean of 625 Bq m(-3). Also, the exhalation rates measured by the passive and active methods were compared and the results of this study were the same, with the active method being 22 % higher than the passive method.

  12. Work to save dose: contrasting effective dose rates from radon exposure in workplaces and residences against the backdrop of public and occupational regulatory limits.

    PubMed

    Whicker, Jeffrey J; McNaughton, Michael W

    2009-09-01

    Office workers are exposed to radon while at work and at home. Though there are a multitude of studies reporting radon concentrations and potential lung and effective doses associated with radon progeny exposure in homes, similar studies in non-mine workplaces are lacking. Additionally, there are few, if any, comparative analyses of radon exposures at more "typical" workplace with residential exposures within the same county. The purposes of this study were to measure radon concentrations in office and residential spaces in the same county and explore the radiation dose implications. Sixty-five track-etch detectors were deployed for 3-mo sampling periods in office spaces and 47 were deployed in residences, all within Los Alamos County, New Mexico. The measured concentrations were used to calculate and compare effective dose rates resulting from exposure while at work and at home. Results showed that full-time office workers receive on average about 8 times greater exposure at home than while in the office (2.3 mSv y-1 vs. 0.3 mSv y-1). The estimated effective dose rate for a more homebound person was about 3 mSv y-1. Estimating effective doses from background radon exposure in the same county as Los Alamos National Laboratory, with thousands of "radiological workers," highlights interesting contrasts in radiation protection standards that span public and occupational settings. For example, the effective dose rate from background radon exposure in unregulated office spaces ranged up to 1.1 mSv y-1, which is similar to the 1 mSv y-1 threshold for regulation of a "radiological worker," as defined in the Department of Energy regulations for occupational exposure. Additionally, the estimated average effective dose total of >3 mSv y-1 from radon background exposure in homes stands in contrast to the 0.1 mSv y-1 air pathway effective public dose limit regulated by the Environmental Protection Agency for radioactive air emissions, and both these are substantially lower

  13. Invited Article: Radon and thoron intercomparison experiments for integrated monitors at NIRS, Japan

    SciTech Connect

    Janik, M. Ishikawa, T.; Omori, Y.; Kavasi, N.

    2014-02-15

    Inhalation of radon ({sup 222}Rn) and its short-lived decay products and of products of the thoron ({sup 220}Rn) series accounts for more than half of the effective dose from natural radiation sources. At this time, many countries have begun large-scale radon and thoron surveys and many different measurement methods and instruments are used in these studies. Consequently, it is necessary to improve and standardize technical methods of measurements and to verify quality assurance by intercomparisons between laboratories. Four international intercomparisons for passive integrating radon and thoron monitors were conducted at the NIRS (National Institute of Radiological Sciences, Japan). Radon exercises were carried out in the 24.4 m{sup 3} inner volume walk-in radon chamber that has systems to control radon concentration, temperature, and humidity. Moreover, the NIRS thoron chamber with a 150 dm{sup 3} inner volume was utilized to provide three thoron intercomparisons. At present, the NIRS is the only laboratory world-wide that has carried out periodic thoron intercomparison of passive monitors. Fifty laboratories from 26 countries participated in the radon intercomparison, using six types of detectors (charcoal, CR-39, LR 115, polycarbonate film, electret plate, and silicon photodiode). Eighteen laboratories from 12 countries participated in the thoron intercomparisons, using two etch-track types (CR-39 and polycarbonate) detectors. The tests were made under one to three different exposures to radon and thoron. The data presented in this paper indicated that the performance quality of laboratories for radon measurement has been gradually increasing. Results of thoron exercises showed that the quality for thoron measurements still needs further development and additional studies are needed to improve its measuring methods. The present paper provides a summary of all radon and thoron international intercomparisons done at NIRS from 2007 to date and it describes the

  14. Invited Article: Radon and thoron intercomparison experiments for integrated monitors at NIRS, Japan

    NASA Astrophysics Data System (ADS)

    Janik, M.; Ishikawa, T.; Omori, Y.; Kavasi, N.

    2014-02-01

    Inhalation of radon (222Rn) and its short-lived decay products and of products of the thoron (220Rn) series accounts for more than half of the effective dose from natural radiation sources. At this time, many countries have begun large-scale radon and thoron surveys and many different measurement methods and instruments are used in these studies. Consequently, it is necessary to improve and standardize technical methods of measurements and to verify quality assurance by intercomparisons between laboratories. Four international intercomparisons for passive integrating radon and thoron monitors were conducted at the NIRS (National Institute of Radiological Sciences, Japan). Radon exercises were carried out in the 24.4 m3 inner volume walk-in radon chamber that has systems to control radon concentration, temperature, and humidity. Moreover, the NIRS thoron chamber with a 150 dm3 inner volume was utilized to provide three thoron intercomparisons. At present, the NIRS is the only laboratory world-wide that has carried out periodic thoron intercomparison of passive monitors. Fifty laboratories from 26 countries participated in the radon intercomparison, using six types of detectors (charcoal, CR-39, LR 115, polycarbonate film, electret plate, and silicon photodiode). Eighteen laboratories from 12 countries participated in the thoron intercomparisons, using two etch-track types (CR-39 and polycarbonate) detectors. The tests were made under one to three different exposures to radon and thoron. The data presented in this paper indicated that the performance quality of laboratories for radon measurement has been gradually increasing. Results of thoron exercises showed that the quality for thoron measurements still needs further development and additional studies are needed to improve its measuring methods. The present paper provides a summary of all radon and thoron international intercomparisons done at NIRS from 2007 to date and it describes the present status on radon and

  15. Evaluation of newly developed nose-only inhalation exposure chamber for nanoparticles.

    PubMed

    Jeon, KiSoo; Yu, Il Je; Ahn, Kang-Ho

    2012-08-01

    In this study, a direct-flow-type nose-only exposure chamber developed for inhalation toxicity experiments using a numerical analysis and experiments is evaluated. Maintaining a uniform flow rate and test article concentration are the critical factors when designing an inhalation exposure chamber. Therefore, this study evaluated whether the flow rate and particle size distribution at the injection nozzles at each port could be maintained with a deviation below 10%. To achieve this requirement, a nose-only exposure chamber flow field was simulated using a numerical analysis method, i.e. computational fluid dynamics (CFD) code FLUENT 6.3.26. Based on the simulation results, a test chamber was built and tested. The flow velocity was measured at the injection nozzle of the chamber and the aerosol particle size distribution was also measured at each port while inserting the test material into the exposure chamber. The results indicated that a uniform flow field distribution at each stage and port, the deviation of the flow velocity, and particle size distribution were all within 10%. Thus, the resulting nose-only exposure chamber could be described as well-designed.

  16. Adult myeloid leukaemia, geology, and domestic exposure to radon and gamma radiation: a case control study in central Italy

    PubMed Central

    Forastiere, F.; Sperati, A.; Cherubini, G.; Miceli, M.; Biggeri, A.; Axelson, O.

    1998-01-01

    OBJECTIVES: To investigate whether indoor randon or gamma radiation might play a part in myeloid leukaemia as suggested by studies based on crude geographical or geological data for exposure assessment. METHODS: For six months randon and gamma radiation was measured with solid state nuclear track detectors and thermoluminescent dosimeters in dwellings of 44 adult male cases of acute myeloid leukaemia and 211 controls (all subjects deceased). Conditional logistic regression ORs (ORs) and 95% confidence intervals (95% CIs) were estimated for quartiles of radon and gamma radiation and for municipality and dwelling characteristics. RESULTS: The risk of leukaemia was associated with an increasing urbanisation index (p value for trend = 0.008). An increased OR was found among those living in more modern houses (OR 3.0, 95% CI 1.4 to 6.6). Confirming the findings of a previous study in the same area, geological features bore a positive association with myeloid leukemia, even by adjusting for level of urbanisation. Contrary to expectations from the previous study, however, no association appeared between myeloid leukaemia and radon and gamma radiation; for the highest quartiles of exposure, ORs were 0.56 (95% CI 0.2 to 1.4) and 0.52 (95% CI 0.2 to 1.4), respectively. Considering only subjects who had lived > or = 20 years in the monitored home and adjusting for urbanisation, there was still no effect of exposure to radiation. CONCLUSIONS: In view of the limited numbers, the results do not in general refute a possible risk of myeloid leukaemia from exposure to indoor radon or gamma radiation, but decrease the credibility of such a relation in the area studied and also of other studies suggesting an effect without monitoring indoor radiation. Some other fairly strong determinants have appeared--that is, level of urbanisation and living in modern houses-- that might need further consideration.   PMID:9614394

  17. World History Of Radon Research And Measurement From The Early 1900's To Today

    SciTech Connect

    George, A. C.

    2008-08-07

    In 1900, Dorn discovered the emanation in the uranium series that eventually became the well-known gas {sup 222}Rn. From 1900 through 1908, it was demonstrated that {sup 222}Rn is a radioactive gas found in tap water, highly condensable at low temperatures with a half-life of approximately 3.7 days and can be collected on charcoal by adsorption. Although, radon was discovered in 1900, the effects of prolonged exposure had been suspected and noted 300 years earlier among underground miners who developed lung cancer. During the period from 1924-1932, it was suggested that radon was the cause of high lung cancer incidence. In 1951, researchers at the university of Rochester N.Y. pointed out that the lung cancer health hazard was from the alpha radiation dose delivered by the radon decay products that deposited in the respiratory tract. The findings of the BEIR Committee Report VI, which was based on epidemiological studies in different groups of mines in the 1950's and 1960's and on laboratory studies, showed that from 60,000 miners over 2,600 developed lung cancer where only 750 were expected.Since 1998, the epidemiological study conducted in Iowa US, showed beyond any reasonable doubt that radon decay products cause lung cancer among women who lived at least twenty years in their homes. This paper will cover early radon measurements in soil, building material, ground water and in different air environments such as in the atmosphere, caves spas, underground mines and in residential indoor air environment. Radon measurements were conducted in many areas for diagnostic purposes. Radon was used as natural tracer to study air masses, vertical diffusion, and atmospheric studies, in earthquake prediction, and as a geological indicator for radium and uranium. In the early radon measurements, electroscopes, electrometers and primitive ionization chambers were used for many years. In the 1940's fast pulse ionization chambers replaced total ionization chambers. From the mid

  18. World History Of Radon Research And Measurement From The Early 1900's To Today

    NASA Astrophysics Data System (ADS)

    George, A. C.

    2008-08-01

    In 1900, Dorn discovered the emanation in the uranium series that eventually became the well-known gas 222Rn. From 1900 through 1908, it was demonstrated that 222Rn is a radioactive gas found in tap water, highly condensable at low temperatures with a half-life of approximately 3.7 days and can be collected on charcoal by adsorption. Although, radon was discovered in 1900, the effects of prolonged exposure had been suspected and noted 300 years earlier among underground miners who developed lung cancer. During the period from 1924-1932, it was suggested that radon was the cause of high lung cancer incidence. In 1951, researchers at the university of Rochester N.Y. pointed out that the lung cancer health hazard was from the alpha radiation dose delivered by the radon decay products that deposited in the respiratory tract. The findings of the BEIR Committee Report VI, which was based on epidemiological studies in different groups of mines in the 1950's and 1960's and on laboratory studies, showed that from 60,000 miners over 2,600 developed lung cancer where only 750 were expected. Since 1998, the epidemiological study conducted in Iowa US, showed beyond any reasonable doubt that radon decay products cause lung cancer among women who lived at least twenty years in their homes. This paper will cover early radon measurements in soil, building material, ground water and in different air environments such as in the atmosphere, caves spas, underground mines and in residential indoor air environment. Radon measurements were conducted in many areas for diagnostic purposes. Radon was used as natural tracer to study air masses, vertical diffusion, and atmospheric studies, in earthquake prediction, and as a geological indicator for radium and uranium. In the early radon measurements, electroscopes, electrometers and primitive ionization chambers were used for many years. In the 1940's fast pulse ionization chambers replaced total ionization chambers. From the mid 1950's

  19. UTILITY OF SHORT-TERM BASEMENT SCREENING RADON MEASUREMENTS TO PREDICT YEAR-LONG RESIDENTIAL RADON CONCENTRATIONS ON UPPER FLOORS.

    PubMed

    Barros, Nirmalla; Steck, Daniel J; William Field, R

    2016-11-01

    This study investigated temporal and spatial variability between basement radon concentrations (measured for ∼7 d using electret ion chambers) and basement and upper floor radon concentrations (measured for 1 y using alpha track detectors) in 158 residences in Iowa, USA. Utility of short-term measurements to approximate a person's residential radon exposure and effect of housing/occupant factors on predictive ability were evaluated. About 60 % of basement short-term, 60 % of basement year-long and 30 % of upper floor year-long radon measurements were equal to or above the United States Environmental Protection Agency's radon action level of 148 Bq m(-3) Predictive value of a positive short-term test was 44 % given the year-long living space concentration was equal to or above this action level. Findings from this study indicate that cumulative radon-related exposure was more closely approximated by upper floor year-long measurements than short-term or year-long measurements in the basement. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. The inverse dose-rate effect and the extrapolation of radon risk estimates from exposures of miners to low-level exposures in homes

    SciTech Connect

    Pushkin, J.S. )

    1994-04-01

    This letter is written in response to a paper in which the author discusses the inverse dose-rate dependence of oncogenic transformation by high-LET radiation. The author asserts that, as a consequence, the extrapolation of results from miners exposed to high levels of radon daughters could overestimate the risk due to environmental exposures. By using a model increased cell sensitivity in one part of the cell cycle, the author assumes an inverse dose-rate effect should occur only at high doses, but the author of this letter points out that this does not imply a lower risk per unit dose at low doses. According to this letter, the existence of an inverse dose-rate effect for high-LET radiation provides no grounds for projecting lower lung cancer risks per unit exposure at environmental radon levels than at the higher radon level in mines. Failure to adjust for any inverse dose-rate effect in the studies of miners can only lead to an underestimation of the environmental risk.

  1. Workplace monitoring for exposures to radon and to other natural sources in Europe: integration of monitoring for internal and external exposures.

    PubMed

    Lopez, M A; Currivan, L; Falk, R; Olko, P; Wernli, C; Castellani, C M

    2004-01-01

    Part of the action of the EURADOS working group (European Radiation Dosimetry Group) on "Harmonisation of Individual Monitoring in Europe" was to investigate how the results from personal dosemeters for external radiation, from monitoring for internal exposure and from workplace monitoring, can be combined into a complete and consistent system of individual monitoring. To facilitate this work, the "EURADOS questionnaire Q3" relating to radon and other natural sources of radiation in the workplace was distributed to relevant institutes across Europe. A total of 24 countries replied to the questionnaire. This study offers an important overview on actual regulations, national standards and reference levels for protection of employees from radon and other natural sources in different workplace scenarios. Information was also collected on individual monitoring and area monitoring to determine individual doses in workplaces with elevated levels of natural radiation. The article discusses in detail the results obtained showing by country the reference level in workplaces for radon gas and other natural sources. In both instances, exposures in mines, other underground workplaces, industry workplaces/waterworks, offices, schools and day-care homes were considered. The resultant data clearly indicate that there is a need for harmonisation among countries, not least in the areas of regulation and use of reference levels in the workplace.

  2. Calibration system for measuring the radon flux density.

    PubMed

    Onishchenko, A; Zhukovsky, M; Bastrikov, V

    2015-06-01

    The measurement of radon flux from soil surface is the useful tool for the assessment of radon-prone areas and monitoring of radon releases from uranium mining and milling residues. The accumulation chambers with hollow headspace and chambers with activated charcoal are the most used devices for these purposes. Systematic errors of the measurements strongly depend on the geometry of the chamber and diffusion coefficient of the radon in soil. The calibration system for the attestation of devices for radon flux measurements was constructed. The calibration measurements of accumulation chambers and chambers with activated charcoal were conducted. The good agreement between the results of 2D modelling of radon flux and measurements results was observed. It was demonstrated that reliable measurements of radon flux can be obtained by chambers with activated charcoal (equivalent volume ~75 l) or by accumulation chambers with hollow headspace of ~7-10 l and volume/surface ratio (height) of >15 cm.

  3. Contribution of radon and radon daughters to respiratory cancer.

    PubMed Central

    Harley, N; Samet, J M; Cross, F T; Hess, T; Muller, J; Thomas, D

    1986-01-01

    This article reviews studies on the contribution of radon and radon daughters to respiratory cancer and proposes recommendations for further research, particularly a national radon survey. The steady-state outdoor radon concentration averages 200 pCi/m3, and indoor levels are about 4 times higher. The primary source of radon in homes is the underlying soil; entry depends on multiple variables and reduced ventilation for energy conservation increases indoor radon levels. Occupational exposures are expressed in units of radon daughter potential energy concentration or working level (WL). Cumulative exposure is the product of the working level and the time exposed. The unit for cumulative exposure is the working level month (WLM). The occupational standard for radon exposure is 4 WLM/year, and 2 WLM/year has been suggested as a guideline for remedial action in homes. Epidemiologic studies show that miners with cumulative radon daughter exposures somewhat below 100 WLM have excess lung cancer mortality. Some 3% to 8% of miners studied have developed lung cancer attributable to radon daughters. All of the underground mining studies show an increased risk of lung cancer with radon daughter exposure. All cell types of lung cancer increased with radon exposure. If radon and smoking act in a multiplicative manner, then the risk for smokers could be 10 times that for nonsmokers. The potential risk of lung cancer appears to be between 1 and 2 per 10,000/WLM, which yields a significant number of lung cancers as some 220 million persons in the United States are exposed on average to 10 to 20 WLM/lifetime. PMID:3830103

  4. EGFR Somatic Mutations in Lung Tumors: Radon Exposure and Passive-smoking in Former- and Never-smoking U.S. Women

    PubMed Central

    Taga, Masataka; Mechanic, Leah E.; Hagiwara, Nobutoshi; Vähäkangas, Kirsi H.; Bennett, William P.; Alavanja, Michael C. R.; Welsh, Judith A.; Khan, Mohammed A.; Lee, Adam; Diasio, Robert; Edell, Eric; Bungum, Aaron; Jang, Jin Sung; Yang, Ping; Jen, Jin; Harris, Curtis C.

    2012-01-01

    Background Lung cancer patients with mutations in EGFR tyrosine kinase have improved prognosis when treated with EGFR inhibitors. We hypothesized that EGFR mutations may be related to residential radon or passive tobacco smoke. Methods This hypothesis was investigated by analyzing EGFR mutations in seventy lung tumors from a population of never and long-term former female smokers from Missouri with detailed exposure assessments. The relationship with passive-smoking was also examined in never-smoking female lung cancer cases from the Mayo clinic. Results Overall, the frequency of EGFR mutation was 41% [95% Confidence Interval (CI): 32-49%]. Neither radon nor passive-smoking exposure was consistently associated with EGFR mutations in lung tumors. Conclusions The results suggest that EGFR mutations are common in female, never-smoking, lung cancer cases from the U.S, and EGFR mutations are unlikely due to exposure to radon or passive-smoking. PMID:22523180

  5. Radon Exposure Assessment and Relative Effective Dose Estimation to Inhabitants of Puglia Region, South Italy

    PubMed Central

    Quarto, Maria; Pugliese, Mariagabriella; La Verde, Giuseppe; Loffredo, Filomena; Roca, Vincenzo

    2015-01-01

    Indoor radon concentrations were measured in dwellings of the Puglia region in Southern Italy using LR-115 passive detectors. The results show that the radon concentrations varied from 15 ± 2 to 2166 ± 133 Bq/m3 with a geometric mean of 114 Bq/m3 and a geometric standard deviation of 2.3. An analysis on the factors affecting radon concentration such as age of the dwellings, floors, and stories, was performed. The mean effective dose to inhabitants has been calculated and found to be 8.2 mSv/y. Finally, for estimation of cancer risks, the lifetime risk and lung cancer cases per years per million have been calculated. PMID:26610543

  6. Radon Exposure Assessment and Relative Effective Dose Estimation to Inhabitants of Puglia Region, South Italy.

    PubMed

    Quarto, Maria; Pugliese, Mariagabriella; La Verde, Giuseppe; Loffredo, Filomena; Roca, Vincenzo

    2015-11-23

    Indoor radon concentrations were measured in dwellings of the Puglia region in Southern Italy using LR-115 passive detectors. The results show that the radon concentrations varied from 15 ± 2 to 2166 ± 133 Bq/m³ with a geometric mean of 114 Bq/m³ and a geometric standard deviation of 2.3. An analysis on the factors affecting radon concentration such as age of the dwellings, floors, and stories, was performed. The mean effective dose to inhabitants has been calculated and found to be 8.2 mSv/y. Finally, for estimation of cancer risks, the lifetime risk and lung cancer cases per years per million have been calculated.

  7. Laboratory measurements on radon exposure effects on local environmental temperature: Implications for satellite TIR measurements

    NASA Astrophysics Data System (ADS)

    Martinelli, Giovanni; Solecki, Andrzej Tomasz; Tchorz-Trzeciakiewicz, Dagmara Eulalia; Piekarz, Magdalena; Karolina Grudzinska, Katarzyna

    Surface latent heat flux (SLHF) is proportional to the heat released by phase changes during solidification, evaporation or melting. Effects of SLHF on the earth's surface could be measured by satellite techniques capable of measuring thermal infrared radiation (TIR). Recent studies have found a possible correlation between SLHF and earthquakes, hence satellite techniques are widely used in research into the possible link between SLHF and earthquakes. Possible fluctuations in SLHF values during seismic periods have been attributed to different causes, such as the expulsion from the ground of greenhouse gases or because of radon. In particular, ionization processes due to radon decay could lead to changes in air temperature. Laboratory experiments have been carried out to highlight the possible role of radon in the thermal environmental conditions of a laboratory-controlled atmospheric volume.

  8. Design of an exposure chamber to test samplers used in the evaluation of personal exposure to nanoparticles

    NASA Astrophysics Data System (ADS)

    Amin, R.; Izadi, H.; Quémerais, B.

    2015-05-01

    The aim of this study was to design a laboratory size exposure chamber for the testing of samplers used to collect personal exposure samples for nanoparticles. A polyethylene cylindrical container with a diameter of 42 cm and height of 60 cm was used as the testing chamber. The chamber was divided into 2 parts by an aluminium honey comb. Particles generated using a 1 jet Collison nebulizer (BGI) operating at a flow rate of 4L/min were inserted into the chamber via a tube located near to the top of the chamber. A heater was inserted just after the nebulizer to avoid condensation of water in the tubing, and dilution air, running at 10L/min was inserted just after the heater. As particle charge can dramatically affect sampling a particle neutralizer was attached to the generation system so as to neutralize the particles before they enter the chamber. A diffusion dryer was used to remove any water from the air stream prior to enter the chamber. A fan was used to mix and distribute the generated particles. After generation and mixing, the particles passed through the aluminium honeycomb which is essential to eliminate any turbulent or unwanted air flow. Six sampling ports along with a pressure gauge were placed on the walls 15 cm from the bottom of the chamber. The pressure gauge was added to ensure the desired pressure is achieved during sampling. The sampling ports allowed for the connection of five samplers and sampling pumps as well as the connection of an ultrafine particle counter. The exposure chamber was developed to assess various samplers for carbon nanotubes and cellulose nanocrystals. Results showed that the chamber was working properly and that mixing was sufficiently uniform to test samplers.

  9. Work to save dose: contrasting effective dose rates from radon exposure in workplaces and residences against the backdrop of public and occupational limits

    SciTech Connect

    Whicker, Jeffrey J; Mcnaughton, Michael W

    2009-01-01

    Office workers are exposed to radon while at work and at home. Though there has been a multitude of studies reporting the measurements of radon concentrations and potential lung and effective doses associated with radon and progeny exposure in homes, similar studies on the concentrations and subsequent effective dose rates in the non-mine workplaces are lacking. Additionally, there are few, if any, comparative analyses of radon exposures at more 'typical' workplace with residential exposures within the same county. The purposes of this study were to measure radon concentrations in office and residential spaces in the same county and explore the radiation dose implications. Sixty-five track-etch detectors were deployed in office spaces and 47 were deployed in residences, all within Los Alamos County, New Mexico, USA. The sampling periods for these measurements were generally about three months. The measured concentrations were used to calculate and compare effective dose rates resulting from exposure while at work and at home. Results showed that full-time office workers receive on average about 8 times greater exposure at home than while in the office (2.3 mSv yr-! versus 0.3 mSv yr-!). The estimated effective dose rate for a more homebound person was about 3 mSv yr-!. Estimating effective doses from background radon exposure in the same county as Los Alamos National Laboratory, with thousands of'radiological workers,' highlights interesting contrasts in radiation protection standards that span public and occupational settings. For example, the effective dose rate from background radon exposure in unregulated office spaces ranged up to 1.1 mSv yr-!, which is similar to the 1 mSv yr-! threshold for regulation ofa 'radiological worker,' as defined in the Department of Energy regulations for occupational exposure. Additionally, the estimated average effective dose total of> 3 mSv yf! from radon background exposure in homes stands in contrast to the 0.1 mSv yr-! air

  10. Radon in Ingleborough / Clapham Cave, North Yorkshire, UK.

    NASA Astrophysics Data System (ADS)

    Gillmore, Gavin

    2015-04-01

    Atmospheric radon concentration was measured at Ingleborough Cave, North Yorkshire during the summer of 2004, and the autumn / winter of 2004/5. Significantly, Ingleborough Cave forms part of a larger system which includes the world famous Gaping Gill pothole. This plunges 105 m (334 ft), contains the tallest unbroken waterfall in England and one of the largest known underground chambers in the UK. Measurements were taken to assess the effects of seasonal and spatial variation, elevation and ventilation on radon concentration in Ingleborough. In this study personal dose exposures for three groups of cave user were identified, and the performance of a variety of radon detection systems evaluated. Summer radon concentrations inside the cave peaked at around 7,000 Bq m-3, although average concentrations were less than 5,000 Bq m-3. During the winter measurement period, average concentrations were around 100 Bq m-3, and a winter / summer ration therefore of 47,4. The average annual radon concentration exceeded the legislative limitations for the workplace of 400 Bq m-3 due in part to a failed fan in the ventilation system. When the fan was running we noted an 80% reduction in radon concentrations although reliability of the fan was problematic due to extensive but relatively rare flooding of the cave system. The radon dose experienced by cave workers and guides in this study exceeded the Ionisation Radiation Regulations limit of 5 mSv/annum, and highlighted that for health and safety reasons the ventilation system should be fully operational during the high radon concentration summer months. Keywords: Radon, Cave, Ingleborough, Detection methods

  11. Radon programmes and health marketing.

    PubMed

    Fojtikova, Ivana; Rovenska, Katerina

    2011-05-01

    Being aware of negative health effects of radon exposure, many countries aim for the reduction of the radon exposure of their population. The Czech radon programme was commenced >20 y ago. Since then experts have gathered a lot of knowledge, necessary legislation has been enacted, tens of thousands of inhabitants have been offered free measurement and subsidy for the mitigation. Despite the effort, the effectiveness of the radon programme seems to be poor. Newly built houses still exhibit elevated radon concentrations and the number of houses mitigated is very low. Is it possible to enhance the effectivity of radon programme while keeping it on a voluntary basis? One possible way is to employ health marketing that draws together traditional marketing theories and science-based strategies to prevention. The potential of using marketing principles in communication and delivery of radon information will be discussed.

  12. Control of indoor radon and radon progeny concentrations

    SciTech Connect

    Sextro, R.G.

    1985-05-01

    There are three general categories of techniques for the control of radon and radon progeny concentrations in indoor air - restriction of radon entry, reduction of indoor radon concentrations by ventilation or air cleaning, and removal of airborne radon progeny. The predominant radon entry process in most residences appears to be pressure driven flow of soil gas through cracks or other openings in the basement, slab, or subfloor. Sealing these openings or ventilation of the subslab or subfloor space are methods of reducing radon entry rates. Indoor radon concentrations may be reduced by increased ventilation. The use of charcoal filters for removal of radon gas in the indoor air by adsorption has also been proposed. Concentrations of radon progeny, which are responsible for most of the health risks associated with radon exposures, can be controlled by use of electrostatic or mechanical filtration. Air circulation can also reduce radon progeny concentrations in certain cases. This paper reviews the application and limitations of each of these control measures and discusses recent experimental results.

  13. Radon: Counseling patients about risk

    SciTech Connect

    Birrer, R.B. )

    1990-09-01

    Exposure to radon and its decay products has increased as the United States has changed from an outdoor society to a largely indoor society. Radon, which is found primarily in the soil, enters houses and buildings through cracks, holes and pipes in foundation walls and floors. Although radon is suspected of being a significant cause of lung cancer, comparisons with other risk factors cannot yet be made. Radon levels in the home can be measured with commercially available kits. Guidelines for reducing the amount of radon in a home are provided by the U.S. Environmental Protection Agency.18 references.

  14. Radon daughters' concentration in air and exposure of joggers at the university campus of Bangalore, India.

    PubMed

    Ashok, G V; Nagaiah, N; Shiva Prasad, N G

    2008-09-01

    The concentration of radon daughters in outdoor air was measured continuously from January 2006 to December 2006 near the Department of Physics, Bangalore University campus, Bangalore. The concentration was measured by collecting air samples at a height of 1 m above the ground level on a glass micro fibre filter paper with a known air flow rate. The results show that the radon progeny concentration exhibits distinct seasonal and diurnal variations that are predominantly caused by changes in the temperature gradient at the soil-atmosphere interface. The concentration was found to be high from 20.00 to 8.00 hrs, when the turbulence mixing was minimum and low during the rest of the time. In terms of the monthly concentration, January was found to be the highest with September/August being the lowest. The diurnal variations in the concentrations of radon progeny were found to exhibit positive correlation with the relative humidity and anti-correlation with the atmospheric temperature. From the measured concentration, an attempt was made to establish the annual effective dose to the general public of the region and was found to be 0.085 mSv/a. In addition, an attempt was also made for the first time to study the variation of inhalation dose with respect to the physical activity levels. Results show that in the light of both the effect of chemical pollutants and radiation dose due to inhalation of radon daughters, evening jogging is advisable.

  15. Performance of NIRS Thoron Chamber System

    NASA Astrophysics Data System (ADS)

    Sorimachi, Atsuyuki; Tokonami, Shinji; Takahashi, Hiroyuki; Kobayashi, Yosuke

    2008-08-01

    In order to carry out thoron sensitivity test for passive radon detectors, a thoron chamber system has been set up at NIRS, Japan. The thoron chamber system consists of four components: the exposure, monitoring, calibration, and humidity control systems, which was mounted in this study due to humidity dependence on the thoron concentration emanated from lantern mantles as the thoron source. The thoron concentration in the thoron chamber is controlled by humidity passed through the thoron source and the weight of the lantern mantle.

  16. Performance of NIRS Thoron Chamber System

    SciTech Connect

    Sorimachi, Atsuyuki; Tokonami, Shinji; Takahashi, Hiroyuki; Kobayashi, Yosuke

    2008-08-07

    In order to carry out thoron sensitivity test for passive radon detectors, a thoron chamber system has been set up at NIRS, Japan. The thoron chamber system consists of four components: the exposure, monitoring, calibration, and humidity control systems, which was mounted in this study due to humidity dependence on the thoron concentration emanated from lantern mantles as the thoron source. The thoron concentration in the thoron chamber is controlled by humidity passed through the thoron source and the weight of the lantern mantle.

  17. Design and construction of a simple, continuous flow sulfur dioxide exposure chamber

    SciTech Connect

    Leetham, J.W.; Ferguson, W.; Dodd, J.L.; Lauenroth, W.K.

    1982-02-01

    For experimental purposes, a reasonably large capacity, low cost, low maintenance chamber was needed to study the long-term (2-4 months) effects of sulfur dioxide on developmental rates of grasshoppers and decomposition rates of plant litter. Internal temperature, humidity, and light controls were not required since the chamber would be used in externally controlled environments. The controlled exposure chamber herein described has proved to be adequate for such studies and satisfied most of the conditions discussed by Heagle and Philbeck. Its utility could be increased by use within an environmentally controlled greenhouse. It is comparatively simple and inexpensive to contruct and maintain.

  18. A creeping suspicion about radon

    SciTech Connect

    Alderson, L.

    1994-10-01

    Who would expect an odorless, invisible gas that occurs nearly everywhere on earth to cause such trouble Yet radon, the gas emitted by decay of uranium in the earth's crust, is one of America's most significant environmental risks, according to the EPA, which estimates that residential radon levels lead to approximately 13,600 lung cancer deaths each year. A new National Cancer Institute analysis of multiple studies of miners confirms early estimates, putting the number at 15,000. No other risk comes close, not even environmental tobacco smoke, which is estimates to cause some 3,000 deaths each year. Hot debate surrounds the assessment of risk from radon exposure to Americans via indoor air and water supplies. The primary culprit is not radon gas itself, but its decay products, including polonium-214 and polonium-218, which have long half-lives and emit alpha particles - positively charged particles - and lung cancer when inhaled. Radon seeps into homes from the ground or is present in water supplies. Waterborne radon may be inhaled as radon or its progeny during household use - cooking or showering - or it may be ingested. But the EPA estimates that water sources contribute only about 5% of total airborne radon exposure, leaving indoor air as the worst offender. While the EPA estimates that approximately 200 cancer cases per year result from exposure to radon from public groundwater systems, estimates of annual lung cancer deaths from indoor air radon range from 7,000 to 30,000.

  19. Radon exposure assessment for underground workers: a case of Seoul Subway Police officers in Korea.

    PubMed

    Song, Myeong Han; Chang, Byung-Uck; Kim, Yongjae; Cho, Kun-Woo

    2011-11-01

    The objective of this study is the systematic and individual assessment of the annual effective dose due to inhaled radon for the Seoul Subway Police officers, Korea. The annual average radon concentrations were found to be in the range of 18.9-114 Bq·m(-3) in their workplaces. The total annual effective doses which may likely to be received on duty were assessed to be in the range of 0.41-1.64 mSv·y(-1). These were well below the recommended action level 10 mSv·y(-1) by ICRP. However, the effective doses were higher than subway station staff in Seoul, Korea.

  20. Radon 222 permeation through different polymers (PVC, EVA, PE and PP) after exposure to gamma radiation or surface treatment by cold plasma

    NASA Astrophysics Data System (ADS)

    Klein, D.; Tomasella, E.; Labed, V.; Meunier, C.; Cetier, Ph.; Robé, M. C.; Chambaudet, A.

    1997-08-01

    In order to limit radon emission during the storage of radioactive wastes and to comply with the different regulations in the storage facility, the packaging used for these types of wastes should include intermediate enclosures, such as polymer membranes used as radon barriers. However, the membrane would be subjected to different types of radiation during long periods of storage, it would have to be regularly monitored for damage. The first aim of this study is to check the efficiency and the continuity of such polymer membranes subjected to different accelerated ageing processes by exposure to gamma radiation. PolyVinyl Chloride (PVC) and Ethylene Vinyl Acetate (EVA) membranes were studied after gamma exposures. Thus, we evaluated the effects of the gamma radiations on the radon permeation coefficient, and the degradation of these polymers due to this exposure. The second objective of this study is to evaluate the modifications of the polymer surface by cold plasma. PolyEthylene (PE) and PolyPropylene (PP) membranes were studied. Exposure of a polymer to a plasma creates reactive sites on the polymer's surface. Different modifications in the surface composition (chemical composition, molecular weight, etc.) can be obtained. The advantage of the plasma process is that it acts within seconds and does not produce any noticeable effects on the bulk properties. The obtained results show that this treatment increases the polymer's efficiency as a radon barrier.

  1. Dosimetric challenges for residential radon epidemiology.

    PubMed

    Steck, Daniel J; Field, R William

    2006-04-01

    Radon concentration alone may not be an adequate surrogate to measure for lung cancer risk in all residential radon epidemiologic lung cancer studies. The dose delivered to the lungs per unit radon exposure can vary significantly with exposure conditions. These dose-effectiveness variations can be comparable to spatial and temporal factor variations in many situations. New technologies that use surface-deposited and implanted radon progeny activities make more accurate dose estimates available for future epidemiologic studies.

  2. Chamber Tests with Human Subjects XX. Hypersensitivity to H as Demonstrated by Patch Tests Before and After Chamber Exposure to H Vapor

    DTIC Science & Technology

    1946-05-15

    intense erythema 4 a. erythema with edema b. dry scaling of scrotum c. maceration of axillary skin 5 a. vesicle b. numerous pinpoint vesicles c. crusting... skin reaction following exposure to H vapor in the man-chamber are discussed. Eight kodachrone prints, illustrating pertinent features, are included...Reactions for a Given Test Dose - 12 F. Changes in Threshold ------------------ 12 G. Abnormal Skin Reactions Following Chamber Exposures to H Vapor

  3. Carcinogenesis and low-level ionizing radiation with special reference to lung cancer and exposure to radon daughters

    SciTech Connect

    Fabrikant, J.I.

    1982-06-01

    The quantitative estimation of the carcinogenic risk of low-dose, high-LET radiation in the case of exposure to radon daughters and lung-cancer is subject to numerous uncertainties. The greatest of these concerns the parametric values of the dose-response curve. We lack knowledge and an understanding of the dosimetry and the distribution of aggregates of radioactivity that remain localized as hot spots in specific regions of the lungs and the influence on greater or lesser risk of lung cancer per average lung dose than uniformly deposited radiation (NRC76). We have only a limited understanding of the response to exposure to high-LET radiations, such as alpha particles, for which linear risk estimates for low doses are less likely to overestimate the risk, and may, in fact, underestimate the risk (BEIR80). Other uncertainties include the length of the latency period, the RBE for alpha radiation relative to gamma radiation, the period during which the radiation risk is expressed, the risk projection model used - whether absolute or relative - for projecting risk beyond the period of observation, the effect of dose rate and protraction of dose, and the influence of differences in the natural incidence of lung cancer in different populations. In addition, uncertainties are introduced by the biological and life-style risk characteristics of humans, for example, the effect of sex, the effect of age at the time of irradiation and at the time of appearance of the cancer, the influence of length of observation or follow-up of the study populations, and the influence of perhaps the most important confounding bias, cigarette-smoking. The collective influence of these uncertainties is such as to deny great credibility to any estimate of human lung cancer risk and other cancer risk that can be made for low-dose, high-LET radon daughter radiation exposure.

  4. Occupational exposure to radon for underground tourist routes in Poland: Doses to lung and the risk of developing lung cancer.

    PubMed

    Walczak, Katarzyna; Olszewski, Jerzy; Politański, Piotr; Zmyślony, Marek

    2017-07-14

    Radon concentrations for 31 Polish underground tourist routes were analyzed. The equivalent dose to the lung, the effective dose and the relative risk were calculated for employees of the analyzed routes on the grounds of information on radon concentrations, work time, etc. The relative risk for lung cancers was calculated using the Biological Effects of Ionizing Radiation (BEIR) VI Committee model. Equivalent doses to the lungs of workers were determined using the coefficients calculated by the Kendall and Smith. The conversion coefficient proposed by the International Atomic Energy Agency (IAEA) in the report No. 33 was used for estimating the effective doses. In 13 routes, the effective dose was found to be above 1 mSv/year, and in 3 routes, it exceeded 6 mSv/year. For 5 routes, the equivalent dose to lungs was higher than 100 mSv/year, and in 1 case it was as high as 490 mSv/year. In 22.6% of underground workplaces the risk of developing lung cancer among employees was about 2 times higher than that for the general population, and for 1 tourist route it was about 5 times higher. The geometric mean of the relative risk of lung cancer for all workers of underground tourist routes was 1.73 (95% confidence interval (CI): 1.6-1.87). Routes were divided into: caves, mines, post-military underground constructions and urban underground constructions. The difference between levels of the relative risk of developing lung cancer for all types of underground tourist routes was not found to be significant. If we include the professional group of the employees of underground tourist routes into the group of occupational exposure, the number of persons who are included in the Category A due to occupational exposure may increase by about 3/4. The professional group of the employees of underground tourist routes should be monitored for their exposure to radon. Int J Occup Med Environ Health 2017;30(5):687-694.

  5. Measurement of potential alpha energy exposure and potential alpha energy concentration and estimating radiation dose of radon in Sari city in the north region of Iran.

    PubMed

    Rahimi, Seyed Ali; Nikpour, Behzad

    2014-12-01

    In dwellings in Sari city in the northern region of Iran, the potential alpha energy exposure (PAEE) and potential alpha energy concentration (PAEC) have been measured and the radiation dose due to radon and its progenies has been estimated. In this study, the dosemeters DOSEman and SARAD GmbH (Germany), which are sensitive to alpha particles, were used. The population of the city of Sari is 495,369 people and the density of population is 116.5 people per km(2). A percentage of the total household population of Sari in areas of geographically different samples was selected. The PAEE, PAEC and radon concentration in four different seasons in a year in homes for sampling were measured. The mean PAEE due to indoor radon in homes of four cities in Sari city was estimated to be 28.23 Bq m(-3) and the mean PAEC was estimated to be 27.11 Bq m(-3). Also the mean indoor radon level was found to be 29.95 Bq m(-3). The annual dose equivalent is ∼0.0151 μSv y(-1). Measurement results show that the average PAEE, PAEC and radon concentration are higher in winter than in other seasons. This difference could be due to stillness and lack of air movement indoors in winter.

  6. Radon testing behavior in a sample of individuals with high home radon screening measurements

    SciTech Connect

    Field, R.W.; Kross, B.C.; Vust, L.J. )

    1993-08-01

    Although radon exposure has been identified as the second leading cause of lung cancer, fewer than 6% of US homeowners test their homes for radon. This report examines participants' follow-up radon testing behavior subsequent to receiving an initial screening radon level greater than 20 pCi/L. Sixty-two participants in the Iowa State-Wide Rural Radon Screening Survey who had radon screening measurements over 20 pCi/L were questioned by phone survey 3 months after receipt of their radon screening result to assess: whether participants were aware of radon's health risk; if participants recalled the radon screening results; how participants perceived the relative health risk of radon and whether participants planned follow-up radon testing. Only 19% of the respondents specifically identified lung cancer as the possible adverse health outcome of high radon exposure, and the majority of participants underestimated the health risks high radon levels pose when compared to cigarettes and x-rays. In addition, less than one third (29%) of the participants actually remembered their radon screening level within 10 pCi/L 3 months after receiving their screening results. Only 53% of the individuals correctly interpreted their screening radon level as being in the high range, and only 39% of the participants planned follow-up radon measurements. Receipt of radon screening test results indicating high radon levels was not an adequate motivational factor in itself to stimulate further radon assessment or mitigation. The findings suggest that free radon screening will not result in a dramatic increase in subsequent homeowner initiated remediation or further recommended radon testing. 13 refs., 1 fig., 5 tabs.

  7. Radon Risk and Remediation: A Psychological Perspective

    PubMed Central

    Hevey, David

    2017-01-01

    Although radon exposure in the home increases the risk of lung cancer, this risk can be managed. However, evidence indicates that testing for radon and subsequent home remediation rates are generally low in many countries. The present perspective outlines some key insights from psychological science that might account for sub-optimal radon protection. Psychological aspects of how the health risks posed by radon are perceived and managed are outlined. There is need to consider radon risk perception in terms of the (a) cognitive and emotional responses to radon and (b) social context in which the radon threat occurs. In addition, the nature of the threat itself is integral to the failure for people to act in response to a radon threat. Finally, the challenges arising from defensive processing of radon threat information are outlined. PMID:28396855

  8. Chromosomal aberrations suggestive of mutagen-related leukemia after 21 years of therapeutic radon exposure

    SciTech Connect

    Rechavi, G.; Berkowicz, M.; Rosner, E.; Neuman, Y.; Ben-Bassat, I.; Ramot, B. )

    1990-08-01

    A 68-year-old woman with acute myelomonocytic leukemia, who was treated annually for 21 consecutive years by therapeutic low-dose radon gas radiation because of spondyloarthritis, is described. The karyotype of the malignant clone was 45,XX, -17, -18,del(5)(q15q33), +t(17;18)(q11.2q23). In 45% of the metaphases, the modal number was between hyperdiploid to near tetraploid. Double minute chromosomes were demonstrated in 60% of the cells. These chromosomal aberrations are suggestive of mutagen-related leukemia.

  9. Validation of the Global Allergy and Asthma European Network (GA(2)LEN) chamber for trials in allergy: Innovation of a mobile allergen exposure chamber.

    PubMed

    Zuberbier, Torsten; Abelson, Mark B; Akdis, Cezmi A; Bachert, Claus; Berger, Uwe; Bindslev-Jensen, Carsten; Boelke, Georg; Bousquet, Jean; Canonica, Giorgio Walter; Casale, Thomas B; Jutel, Marek; Kowalski, Marek L; Madonini, Enzo; Papadopoulos, Nikolaos G; Pfaar, Oliver; Sehlinger, Torsten; Bergmann, Karl-Christian

    2017-04-01

    Field clinical trials of pollen allergy are affected by the impossibility of predicting and determining individual allergen exposure because of many factors (eg, pollen season, atmospheric variations, pollutants, and lifestyles). Environmental exposure chambers, delivering a fixed amount of allergen in a controlled environmental setting, can overcome these limitations. Environmental exposure chambers are currently already used in phase 2, 3, and even 4 trials. Unfortunately, few chambers exist in the world, and this makes it difficult to perform large, multicenter clinical trials. The new Global Allergy and Asthma European Network (GA(2)LEN) mobile exposure chamber is a step forward because the mobility of the chamber makes it convenient for patients to participate in clinical testing. This study was made to validate the reproducibility, sensitivity, and specificity of the results obtained in the new GA(2)LEN chamber. Seventy-two adult patients (19-61 years old) with allergic rhinitis with or without asthma caused by grass pollen were included in different clinical validation tests. Total symptom scores and total nasal symptom scores were recorded at time zero (0) and every 10 minutes during exposures, along with nasal and respiratory parameters. Exposure tests confirmed the reproducibility between subsequent runs and the sensitivity (P < .00001 vs patients exposed to placebo) and specificity (very low score in nonallergic subjects) in the GA(2)LEN chamber. No adverse reactions were recorded during the tests. The mobility of the GA(2)LEN chamber provides a new, potentially effective, and safe way of generating reliable data in allergy multicenter clinical trials. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  10. Predicting indoor radon-222 concentration

    SciTech Connect

    Stowe, M.H.

    1994-12-31

    Radon, a cause of lung cancer among miners, is being investigated as a source of lung cancer in the general population due to long-term low-level exposures in residences. Assessment of cumulative residential radon exposure entails measurements in past residences, some of which no longer exist or are not accessible. Estimates of radon concentrations in these missing homes are necessary for analysis of the radon-lung cancer association. Various approaches have been used by researchers attempting to predict the distribution of radon measurements in homes from specified geological and building characteristics. This study has modelled the set of basement radon measurements of 3788 Connecticut homes with several of these approaches, in addition to a descriptive tree method not previously utilized, and compared their validity on a random subset of homes not used in model construction. Each geographical and geological variable was more predictive of radon concentration than any of the housing characteristics. The single variable which explained the largest fraction of the variability in radon readings was the mean radon concentration for the zipcode area in which the house was located (R{sup 2} = .157). Soil characteristics at individual housing sites were not available for these analyses. They would be expected to increase the predictive power of the models. Multiple regression models, both additive and multiplicative, were not able to explain more than 22% of the variation in radon readings. Variables found to be significant in these models were zipcode mean, residential radon mean of bedrock unit, building age, type of foundation walls, type of water supply, aeroradioactivity reading, and lithology of the bedrock. A site potential index, based upon a classification of the bedrock underlying the house, was a better predictor of indoor radon level than other single geological variables, yet only explained 8% of the radon variability.

  11. A statistical evaluation of the influence of housing characteristics and geogenic radon potential on indoor radon concentrations in France.

    PubMed

    Demoury, C; Ielsch, G; Hemon, D; Laurent, O; Laurier, D; Clavel, J; Guillevic, J

    2013-12-01

    Radon-222 is a radioactive natural gas produced by the decay of radium-226, known to be the main contributor to natural background radiation exposure. Effective risk management needs to determine the areas in which the density of buildings with high radon levels is likely to be highest. Predicting radon exposure from the location and characteristics of a dwelling could also contribute to epidemiological studies. Beginning in the nineteen-eighties, a national radon survey consisting in more than 10,000 measurements of indoor radon concentrations was conducted in French dwellings by the Institute for Radiological Protection and Nuclear Safety (IRSN). Housing characteristics, which may influence radon accumulation in dwellings, were also collected. More recently, the IRSN generated a French geogenic radon potential map based on the interpretation of geological features. The present study analyzed the two datasets to investigate the factors influencing indoor radon concentrations using statistical modeling and to determine the optimum use of the information on geogenic radon potential that showed the best statistical association with indoor radon concentration. The results showed that the variables associated with indoor radon concentrations were geogenic radon potential, building material, year of construction, foundation type, building type and floor level. The model, which included the surrounding geogenic radon potential (i.e. the average geogenic radon potential within a disc of radius 20 km centered on the indoor radon measurement point) and variables describing house-specific factors and lifestyle explained about 20% of the overall variability of the logarithm of radon concentration. The surrounding geogenic radon potential was fairly closely associated with the local average indoor radon concentration. The prevalence of exposure to radon above specific thresholds and the average exposures to radon clearly increased with increasing classes of geogenic radon

  12. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres

    SciTech Connect

    Hopke, P.K.

    1990-01-01

    The chemical and physical behavior of the {sup 218}Po atom immediately following its formation by the alpha decay of radon must be understood if the exposure to radon progeny is to be fully assessed. Two areas of radon progeny behavior will be studied; laboratory studies and studies in actual indoor environments. Laboratory studies include: Measure the neutralization rate of {sup 218}Po{sup +}{sub x} in O{sub 2} at low radon concentrations. Determine the formation rates of {center dot}OH, {center dot}O, or other oxidative radicals formed by the radiolysis of air following radon decay. Examine the formation of particles by the radiolytic oxidation of substances and measure the rate of ion-induced nucleation in the sulfuric acid-water vapor system with and without NH{sub 3} additions using a thermal diffusion cloud chamber. Exposure studies include: Initiate measurements of the activity size distribution in actual homes with occupants present; Initiate a prospective study of the utility of measurement of deposited {sup 210}Pb embedded in glass surfaces as a measure of the long-term, integrated exposure of the population to radon, and acquire the components and begin to develop the methodology to determine the hygroscopicity of the indoor aerosol.

  13. Investigation of radon level in air and tap water of workplaces at Thailand Institute of Nuclear Technology, Thailand

    NASA Astrophysics Data System (ADS)

    Sola, P.; Youngchuay, U.; Kongsri, S.; Kongtana, A.

    2017-06-01

    Thailand Institute of Nuclear Technology (TINT) has continuously monitored radiation exposure and radionuclide in workplaces specifically radon gas to estimate effective dose for workers. Radon exposure is the second leading cause of lung cancer in the world. In this study, radon in air and tap water at building no. 3, 7, 8, 9 and 18 on Ongkharak site of TINT have been measured for 5 years from 2012 to 2016. Radon level in air and tap water were investigated on 83 stations (workplaces) and 54 samples, respectively. Radon concentrations in air and tap water were measured by using the pulsed ionization chamber (ATMOS 12 DPX). Indoor radon concentrations in air were in the range of 12-138 Bq.m-3 with an average value of 30.13±17.05 Bq.m-3. Radon concentrations in tap water were in the range of 0.10 to 2.89 Bq.l-1 with an average value of 0.51±0.55 Bq.l-1. The results of radon concentrations at TINT were below the US Environmental Protection Agency (US EPA) safety limit of 148 Bq.m-3 and 150 Bq.l-1, for, air and tap water, respectively. The average effective dose for TINT’s workers due to indoor radon exposure was approximately 0.20±0.11 mSv.y-1. The value is 100 times less than the annual dose limit for limit occupational radiation worker defined by the International Commission on Radiological Protection (ICRP). As a result, the TINT’s workplaces are radiologically safe from radon content in air and tap water.

  14. Inter-comparison of radon detectors for one to four week measurement periods.

    PubMed

    Gunning, G A; Murray, M; Long, S C; Foley, M J; Finch, E C

    2016-03-01

    Seven different types of radon detectors (Atmos 12 dpx, RAD7, RStone, Sun Nuclear 1028, Ramon 2.2, Canary and CR-39) were compared for exposure periods of 1, 2, 3 and 4 weeks. The comparison was conducted under two conditions: (a) in a purpose-built radon chamber with an average radon concentration of 2560 Bq m(-3) (b) in a home environment with a radon concentration of 57 Bq m(-3), in both cases measured by the reference detector (Atmos 12 dpx) with a  ±10% uncertainty range. In (a) 5 out of 8 detectors recorded radon concentrations within the Atmos uncertainty range and all detectors recorded within  ±15%; in (b) 3 out of 9 detectors recorded within the Atmos uncertainty range and 6 out of 9 measured within  ±20%, for a 4 week measurement. The results from this study show that radon surveys can be conducted for shorter periods than the recommended 3 months where a rapid indication is needed of whether the radon concentration is above the reference level, such as when assessing the concentration during and after remediation work.

  15. Exposure chamber measurements of mass transfer and partitioning at the plant/air interface.

    PubMed

    Maddalena, Randy L; McKone, Thomas E; Kado, Norman Y

    2002-08-15

    Dynamic measures of air and vegetation concentrations in an exposure chamber and a two-box mass balance model are used to quantify factors that control the rate and extent of chemical partitioning between vegetation and the atmosphere. A continuous stirred flow-through exposure chamber was used to investigate the gas-phase transfer of pollutants between air and plants. A probabilistic two-compartment mass balance model of plant/air exchange within the exposure chamber was developed and used with measured concentrations from the chamber to simultaneously evaluate partitioning (Kpa), overall mass transfer across the plant/air interface (Upa), and loss rates in the atmosphere (Ra) and aboveground vegetation (Rp). The approach is demonstrated using mature Capsicum annuum (bell pepper) plants exposed to phenanthrene (PH), anthracene (AN), fluoranthene (FL) and pyrene (PY). Measured values of log Kpa (V[air]/V[fresh plant]) were 5.7, 5.7, 6.0, and 6.2 for PH, AN, FL, and PY, respectively. Values of Upa (m d(-1)) under the conditions of this study ranged from 42 for PH to 119 for FL. After correcting for wall effects, the estimated reaction half-lives in air were 3, 9, and 25 h for AN, FL and PY. Reaction half-lives in the plant compartment were 17, 6, 17, and 5 d for PH, AN, FL, and PY, respectively. The combined use of exposure chamber measurements and models provides a robust tool for simultaneously measuring several different transfer factors that are important for modeling the uptake of pollutants into vegetation.

  16. The health risk of radon

    SciTech Connect

    Conrath, S.M.; Kolb, L.

    1995-10-01

    Although radon is the second leading cause of lung cancer in the United States, second only to cigarette smoking, many members of the public are not aware that radon is one of the most serious environmental cancer risks in the US. Based on extensive data from epidemiological studies of underground miners, radon has been classified as a known human carcinogen. In contrast to most pollutants, the assessment of human risk from radon is based on human occupational exposure data rather than animal data. That radon causes lung cancer has been well established by the scientific community. More is known about radon than most other cancer causing environmental carcinogens. While there are some uncertainties involved when estimating radon risk to the public, it is important to recognize that the risk information is based on human data and that the uncertainties have been addressed in the risk assessment. The US Environmental Protection Agency (EPA) estimates that the number of annual US lung cancer deaths due to residential radon exposures is approximately 14,000 with an uncertainty range of 7,000 to 30,000. The abundant information on radon health risks that supports EPA`s risk assessment indicates that recommendations for public action by the federal government and other public health organizations constitute prudent public policy.

  17. 2014 ICHLNRRA intercomparison of radon/thoron gas and radon short-lived decay products measuring instruments in the NRPI Prague.

    PubMed

    Jílek, K; Timková, J

    2015-06-01

    During the Eighth International Conference on High Levels of Natural Radiation and Radon Areas held in autumn 2014 at Prague, the third intercomparison of radon/thoron gas and radon short-lived decay products measurement instruments was organised by and held at the Natural Radiation Division of the National Radiation Protection Institute (NRPI; SÚRO v.v.i.) in Prague. The intercomparison was newly focussed also on continuous monitors with active sampling adapters capable to distinguish radon/thoron gas in their mix field.The results of radon gas measurements carried out in the big NRPI radon chamber indicated very well an average deviation of up to 5 % from the reference NRPI value for 80 % of all the exposed instruments. The results of equilibrium equivalent concentration continuous monitors indicated an average deviation of up to 5 % from the reference NRPI value for 40 % of all the exposed instruments and their ~8-10 % shift compared with the NRPI. The results of investigated ambient conditions upon response of exposed continuous monitors indicated influence of aerosol changes upon response of radon monitors with an active air sampling adapters through the filter, only. The exposures of both radon/thoron gas discriminative continuous monitors and passive detectors have been indicated inconsistent results: on one hand, their excellent agreement up to several per cent for both the gases, and on the other hand, systematic unsatisfactory differences up to 40 %. Additional radon/thoron exercises are recommended to improve both the instruments themselves and quality of their operators.

  18. Mutagenicity of radon and radon daughters

    SciTech Connect

    Evans, H.H.

    1991-01-01

    The objective of our research is to investigate the dose-response relationship of the lethal and mutagenic effects of exposure of cells to radon and its decay products. Dose rate dependence and the nature of the DNA lesion will be studied, using the thymidine kinase and HPRT loci to measure mutation frequency. A deficiency in DNA repair is shown to lead to a greater proportion of mutants with intergenic lesions. The cytotoxic effects of radon and its daughters are similar in human TK6 lymphoblasts and mouse L5178Y lymphoblasts, the cell line used in previous experiments. The results of molecular analysis of four spontaneous and 25 X-radiation induced HPRT{sup {minus}} mutants. Eleven radon-induced HPRT{sup {minus}} mutants have been isolated, and will be analyzed in a similar fashion. 9 figs.

  19. Mutagenicity of radon and radon daughters

    NASA Astrophysics Data System (ADS)

    Evans, H. H.

    The objective of our research is to investigate the dose-response relationship of the lethal and mutagenic effects of exposure of cells to radon and its decay products. Dose rate dependence and the nature of the DNA lesion will be studied, using the thymidine kinase and HPRT loci to measure mutation frequency. A deficiency in DNA repair is shown to lead to a greater proportion of mutants with intergenic lesions. The cytotoxic effects of radon and its daughters are similar in human TK6 lymphoblasts and mouse L5178Y lymphoblasts, the cell line used in previous experiments. The results of molecular analysis of four spontaneous and 25 X-radiation induced HPRT(-) mutants. Eleven radon-induced HPRT(-) mutants have been isolated, and will be analyzed in a similar fashion.

  20. First radon measurements and occupational exposure assessments in underground geodynamic laboratory the Polish Academy of Sciences Space Research Centre in Książ Castle (SW Poland).

    PubMed

    Fijałkowska-Lichwa, Lidia; Przylibski, Tadeusz A

    2016-12-01

    The article presents the results of the first radon activity concentration measurements conducted continuously between 17(th) May 2014 and 16(th) May 2015 in the underground geodynamic laboratory of the Polish Academy of Sciences Space Research Centre in Książ. The data were registered with the use of three Polish semiconductor SRDN-3 detectors located the closest (SRDN-3 No. 6) to and the furthest (SRDN-3 No. 3) from the facility entrance, and in the fault zone (SRDN-3 No. 4). The study was conducted to characterize the radon behaviour and check it possibility to use with reference to long- and short-term variations of radon activity concentration observed in sedimentary rocks strongly fractured and intersected by systems of multiple faults, for integrated comparative assessments of changes in local orogen kinetics. The values of radon activity concentration in the underground geodynamic laboratory of the Polish Academy of Sciences (PAN) Space Research Centre in Książ undergo changes of a distinctly seasonal character. The highest values of radon activity concentration are recorded from late spring (May/June) to early autumn (October), and the lowest - from November to April. Radon activity concentrations varied depending on the location of measurement points. Between late spring and autumn they ranged from 800 Bq·m(-3) to 1200 Bq·m(-3), and even 3200 Bq·m(-3) in the fault zone. Between November and April, values of radon activity concentration are lower, ranging from 500 Bq·m(-3) to 1000 Bq·m(-3) and 2700 Bq·m(-3) in the fault zone. The values of radon activity concentration recorded in the studied facility did not undergo short-term changes in either the whole annual measuring cycle or any of its months. Effective doses received by people staying in the underground laboratory range from 0.001 mSv/h to 0.012 mSv/h. The mean annual effective dose, depending on the measurement site, equals 1 or is slightly higher than 10 mSv/year, while the maximum

  1. Recoil-deposited Po-210 in radon dwellings

    SciTech Connect

    Samuelsson, C.

    1990-12-31

    Short-lived decay products of Rn-222 plate out on all surfaces in a house containing radon gas. Following the subsequent alpha decays of the mother nuclei, the daughter products Pb-214 and Pb-210 are superficially and permanently absorbed. Due to its long half-life (22 y) the activity of absorbed Pb-210 accumulates in the surface. The activity of Pb-210, or its decay products, can thus reflect the past randon daughter and plate-out history of a house over several decades. Our results and experience from measurements of Po-210 and Rn-222 in 22 dwellings will be presented. In these studies the Po-210 surface activity of one plane glass sheet per dwelling (window panes were not used) has been determined and compared with the period of exposure times the mean radon concentration measured over a two-month period. Considering the large uncertainty in the integrated radon exposure estimate the surface {sup 210}Po correlates well (r=0.73) with the accumulated radon exposure. The {sup 210}Po activity of the glass samples has been measured non-destructively using an open-flow pulse ionization chamber and this detector has also been successfully applied in field exercises.

  2. Impact of measurement error in radon exposure on the estimated excess relative risk of lung cancer death in a simulated study based on the French Uranium Miners' Cohort.

    PubMed

    Allodji, Rodrigue S; Leuraud, Klervi; Thiébaut, Anne C M; Henry, Stéphane; Laurier, Dominique; Bénichou, Jacques

    2012-05-01

    Measurement error (ME) can lead to bias in the analysis of epidemiologic studies. Here a simulation study is described that is based on data from the French Uranium Miners' Cohort and that was conducted to assess the effect of ME on the estimated excess relative risk (ERR) of lung cancer death associated with radon exposure. Starting from a scenario without any ME, data were generated containing successively Berkson or classical ME depending on time periods, to reflect changes in the measurement of exposure to radon ((222)Rn) and its decay products over time in this cohort. Results indicate that ME attenuated the level of association with radon exposure, with a negative bias percentage on the order of 60% on the ERR estimate. Sensitivity analyses showed the consequences of specific ME characteristics (type, size, structure, and distribution) on the ERR estimates. In the future, it appears important to correct for ME upon analyzing cohorts such as this one to decrease bias in estimates of the ERR of adverse events associated with exposure to ionizing radiation.

  3. The role of the implementation of policies for the prevention of exposure to Radon in Brazil-a strategy for controlling the risk of developing lung cancer.

    PubMed

    Lino, Aline da Rocha; Abrahão, Carina Meira; Amarante, Marcus Paulo Fernandes; de Sousa Cruz, Marcelo Rocha

    2015-01-01

    Lung cancer is the leading cause of cancer death in the United States and other industrialised countries. The most important risk factor is active smoking. However, given the increased incidence of lung cancer in non-smokers, it is necessary to improve knowledge regarding other risk factors. Radon (Rn) is a noble gas and is the most important natural source of human exposure to ionizing radiation. Exposure to high levels of this radioactive gas is related to an increased risk of developing lung cancer. The objective of this work is to highlight the importance of measuring indoor concentration of this gas and identify which steps should be taken for achieving radiological protection. A survey was conducted on the websites of the National Health Surveillance Agency (ANVISA), LAMIN (Mineral Analysis Laboratory), CPRM (Geological Survey of Brazil), Ministry of Health and PubMed. Using the words 'radon', 'lung', 'cancer', and PubMed®, 1,371 results were obtained; when using the words 'radon', 'lung', 'cancer', and with 'Brazil' or 'Brazilians', only six results were obtained. We emphasise that lung cancer is a major public health problem and the exposure to Rn indoors should be considered as a risk factor for lung cancer in non-smokers. Buildings or houses with high concentrations of Rn should be identified. However, currently in Brazil-a country with great potential for mineral extraction-there are no specific regulated recommendations to control indoor exposure to Rn.

  4. STUDY OF RADIATION EXPOSURE DUE TO RADON, THORON AND PROGENY IN THE INDOOR ENVIRONMENT OF YAMUNA AND TONS VALLEYS OF GARHWAL HIMALAYA.

    PubMed

    Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Prasad, Ganesh; Mishra, Rosaline; Ramola, R C

    2016-10-01

    Long-term measurements of indoor radon, thoron and their progeny concentrations have been carried out in dwellings of Yamuna and Tons Valleys of Uttarkashi, Garhwal Himalaya to investigate the health risk associated with inhalation of radon, thoron and progeny. The experimentally determined values of radon, thoron and progeny concentrations were used to estimate the annual inhalation doses and annual effective doses. The annual inhalation dose has been found to vary from 0.8 to 3.9 mSv y(-1) with an average of 1.8 mSv y(-1) The annual effective dose from the exposure to radon and its progeny in the study area has been found to vary from 0.1 to 2.4 mSv with an average of 1.2±0.6 mSv. Similarly, the annual effective dose due to thoron and its progeny has been found to vary from 0.2 to 1.5 mSv with an average of 0.6±0.4. The measurement techniques and results obtained are discussed in detail. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. Association of School District Policies for Radon Testing and Radon-Resistant New Construction Practices with Indoor Radon Zones.

    PubMed

    Foster, Stephanie; Everett Jones, Sherry

    2016-12-13

    Radon is a naturally occurring, colorless, odorless, and tasteless radioactive gas. Without testing, its presence is unknown. Using nationally representative data from the 2012 School Health Policies and Practices Study, we examined whether the prevalence of school district policies for radon testing and for radon-resistant new construction practices varied by district location in relation to the U.S. Environmental Protection Agency Map of Radon Zones. Among school districts located in counties with high predicted average indoor radon, 42.4% had policies for radon testing and 37.5% had policies for radon-resistant new construction practices. These findings suggest a critical need for improved awareness among policy makers regarding potential radon exposure for both students and school staff.

  6. Association of School District Policies for Radon Testing and Radon-Resistant New Construction Practices with Indoor Radon Zones

    PubMed Central

    Foster, Stephanie; Everett Jones, Sherry

    2016-01-01

    Radon is a naturally occurring, colorless, odorless, and tasteless radioactive gas. Without testing, its presence is unknown. Using nationally representative data from the 2012 School Health Policies and Practices Study, we examined whether the prevalence of school district policies for radon testing and for radon-resistant new construction practices varied by district location in relation to the U.S. Environmental Protection Agency Map of Radon Zones. Among school districts located in counties with high predicted average indoor radon, 42.4% had policies for radon testing and 37.5% had policies for radon-resistant new construction practices. These findings suggest a critical need for improved awareness among policy makers regarding potential radon exposure for both students and school staff. PMID:27983613

  7. Estimated risk of lung cancer from exposure to radon decay products in U.S. homes: A brief review

    NASA Astrophysics Data System (ADS)

    Nero, Anthony V.

    Recent analyses now permit direct estimation of the risks of lung cancer from radon decay products in U.S. homes. Analysis of data from indoor monitoring in single-family homes yields a tentative frequency distribution of annual-average 222Rn concentrations with an arithmetic mean of 55 Bq m -3 and approximately 2% of homes having 300 Bq m -3 or more. Application of the results of occupational epidemiological studies to indoor exposures, either directly or using recent advances in lung dosimetry, suggests that the average indoor concentration entails a lifetime risk of lung cancer of about 0.4%, contributing about 10% of the total risk of lung cancer. The risk to individuals occupying the homes with 300 Bq m -3 or more for their lifetimes is estimated to exceed 2%, with risks from the homes with thousands of Bq m -3 correspondingly higher, even exceeding the total risk of premature death due to cigarette smoking. Such average and high-level risks greatly exceed ordinarily-considered environmental risks, forcing development of a new perspective on environmental exposures.

  8. Assessment of pumped mercury vapour adsorption tubes as passive samplers using a micro-exposure chamber.

    PubMed

    Brown, Richard J C; Burdon, Melia K; Brown, Andrew S; Kim, Ki-Hyun

    2012-09-01

    Mercury vapour adsorption tubes manufactured for pumped sampling and analysis have been evaluated for their performance as passive samplers. This has been done by exposing these tubes in a novel micro-exposure chamber. The uptake rates of these tubes have been found to be low (approximately 0.215 ml min(-1)) as compared to bespoke passive samplers for mercury vapour (typically in excess of 50 ml min(-1)). The measured uptake rates were shown to vary significantly between tubes and this was attributed to the variability in the air-sorbent interface and the proportion of the cross sectional area removed by the crimp in the quartz tubes used to secure the sorbent material. As a result of this variability the uptake rate of each tube must be determined using the micro-exposure chamber prior to deployment. Results have shown that the uptake rate determined in the micro-exposure chamber is invariant of concentration, and therefore these uptakes rates may be determined at a high mercury vapour concentration for many tubes at once in less than one hour. The uptake rate of the adsorption tubes under these conditions may be determined with a precision of 5%. Measurements made on a limited field trial in indoor and outdoor ambient air have shown that these tubes give results in acceptable agreement with more traditional pumped sampling methods, although longer sampling periods are required in order to reduce the uncertainty of the measurement, which is currently approximately 30%.

  9. Quantification of Cigarette Smoke Particle Deposition In Vitro Using a Triplicate Quartz Crystal Microbalance Exposure Chamber

    PubMed Central

    Adamson, Jason; Thorne, David; McAughey, John; Dillon, Deborah; Meredith, Clive

    2013-01-01

    There are a variety of smoke exposure systems available to the tobacco industry and respiratory toxicology research groups, each with their own way of diluting/delivering smoke to cell cultures. Thus a simple technique to measure dose in vitro needs to be utilised. Dosimetry—assessment of dose—is a key element in linking the biological effects of smoke generated by various exposure systems. Microbalance technology is presented as a dosimetry tool and a way of measuring whole smoke dose. Described here is a new tool to quantify diluted smoke particulate deposition in vitro. The triplicate quartz crystal microbalance (QCM) chamber measured real-time deposition of smoke at a range of dilutions 1 : 5–1 : 400 (smoke : air). Mass was read in triplicate by 3 identical QCMs installed into one in vitro exposure chamber, each in the location in which a cell culture would be exposed to smoke at the air-liquid interface. This resulted in quantification of deposited particulate matter in the range 0.21–28.00 μg/cm2. Results demonstrated that the QCM could discriminate mass between dilutions and was able to give information of regional deposition where cell cultures would usually be exposed within the chamber. Our aim is to use the QCM to support the preclinical (in vitro) evaluation of tobacco products. PMID:23484139

  10. Soil radon measurements in the Canadian cities.

    PubMed

    Chen, J; Moir, D; MacLellan, K; Leigh, E; Nunez, D; Murphy, S; Ford, K

    2012-08-01

    Radon has been identified as the second leading cause of lung cancer after tobacco smoking. Information on indoor radon concentrations is required to assess the lung cancer burden due to radon exposure. Since radon in soil is believed to be the main source of radon in homes, measurements of soil gas radon concentrations can be used to estimate variations in radon potential of indoor environments. This study reports surveys of natural background variation in soil radon levels in four cities, Montreal, Gatineau, Kingston and the largest Canadian city of Toronto. A total of 212 sites were surveyed. The average soil gas radon concentrations varied significantly from site to site, and ranged from below detection limit to 157 kBq m(-3). For each site, the soil radon potential (SRP) index was determined with the average soil radon concentration and average soil permeability measured. The average SRP indexes are 20±16, 12±11, 8±9 and 12±10 for Montreal, Gatineau, Kingston and Toronto, respectively. The results provide additional data for the validation of an association between indoor and soil radon potentials and for the development of radon potential map of Canada.

  11. Doses and lung cancer risks from exposure to radon and plutonium.

    PubMed

    Marsh, James W; Harrison, John D; Laurier, Dominique; Birchall, Alan; Blanchardon, Eric; Paquet, François; Tirmarche, Margot

    2014-11-01

    Epidemiological studies of the French uranium miners and the plutonium workers at the Mayak nuclear facility have provided excess relative risk (ERR) estimates per unit absorbed lung dose from alpha radiation. The aim of this paper was to review these two studies and to derive values of the relative biological effectiveness (RBE) of alpha particles for the induction of lung cancer. We examined and compared the dosimetry assumptions and methodology used in the epidemiological studies of uranium miners and the plutonium workers. Values of RBE were obtained by comparing risk coefficients including comparison of lifetime risks for a given population. To do this, preliminary calculations of lifetime risks following inhalation of plutonium were carried out. Published values of risk per unit dose following inhalation of radon progeny and plutonium were in agreement despite the very different dose distributions within the lungs and the different ways the doses were calculated. Values of RBE around 10-20 were obtained by comparing ERR values, but with wide uncertainty ranges. Comparing lifetime risks gave similar values (10, 19 and 21). This supports the use of a radiation weighting factor of 20 for alpha particles for radiation protection purposes.

  12. Determination of radon and radium concentrations in drinking water samples around the city of Kutahya.

    PubMed

    Sahin, Latife; Cetinkaya, Hakan; Murat Saç, Müslim; Içhedef, Mutlu

    2013-08-01

    The concentration of radium and radon has been determined in drinking water samples collected from various locations of Kutahya city, Turkey. The water samples are taken from public water sources and tap water, with the collector chamber method used to measure the radon and radium concentration. The radon concentration ranges between 0.1 and 48.6±1.7 Bq l(-1), while the radium concentration varies from a minimum detectable activity of <0.02-0.7±0.2 Bq l(-1) in Kutahya city. In addition to the radon and radium levels, parameters such as pH, conductivity and temperature of the water, humidity, pressure, elevation and the coordinates of the sampling points have also been measured and recorded. The annual effective dose from radon and radium due to typical water usage has been calculated. The resulting contribution to the annual effective dose due to radon ingestion varies between 0.3 and 124.2 μSv y(-1); the contribution to the annual effective dose due to radium ingestion varies between 0 and 143.3 μSv y(-1); the dose contribution to the stomach due to radon ingestion varies between 0.03 and 14.9 μSv y(-1). The dose contribution due to radon inhalation ranges between 0.3 and 122.5 μSv y(-1), assuming a typical transfer of radon in water to the air. For the overwhelming majority of the Kutahya population, it is determined that the average radiation exposure from drinking water is less than 73.6 µSv y(-1).

  13. Assessing the level of chromosome aberrations in peripheral blood lymphocytes in long-term resident children under conditions of high exposure to radon and its decay products.

    PubMed

    Druzhinin, Vladimir G; Sinitsky, Maxim Yu; Larionov, Aleksey V; Volobaev, Valentin P; Minina, Varvara I; Golovina, Tatiana A

    2015-09-01

    In this study, the frequency and spectrum of chromosomal aberrations were analysed in samples of peripheral blood from 372 (mean age = 12.24 ± 2.60 years old) long-term resident children in a boarding school (Tashtagol city, Kemerovo Region, Russian Federation) under conditions of high exposure to radon and its decay products. As a control group, we used blood samples from people living in Zarubino village (Kemerovo Region, Russian Federation). We discovered that the average frequencies of single and double fragments, chromosomal exchanges, total number of aberrations, chromatid type, chromosome type and all types of aberrations were significantly increased in the exposed group. This is evidence of considerable genotoxicity to children living under conditions of high exposure to radon compared to children living under ecological conditions without increased radon radiation. © The Author 2015. Published by Oxford University Press on behalf of the UK Environmental Mutagen Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Radon and radon daughter measurements in solar buildings.

    PubMed

    George, A C; Knutson, E O; Franklin, H

    1983-08-01

    Measurements of radon and radon daughters in 11 buildings in five states, using active or passive solar heating, showed no significant excess in concentrations over the levels measured in buildings with conventional heating systems. Radon levels in two buildings using rock storage in their active solar systems exceeded the U.S. Nuclear Regulatory Commission's limit of 3 pCi/l. for continuous exposure in uncontrolled areas. In the remainder of the buildings, radon concentrations were found to be at levels considered to be normal. It appears that the slightly elevated indoor radon concentrations result from the local geological formations and from the tightening of the buildings rather than as a result of the solar heating technology.

  15. γ-H2AX/53BP1/pKAP-1 foci and their linear tracks induced by in vitro exposure to radon and its progeny in human peripheral blood lymphocytes

    PubMed Central

    Ding, Defang; Zhang, Yaping; Wang, Jing; Wang, Xufei; Fan, Dunhuang; He, Linfeng; Zhang, Xuxia; Gao, Yun; Li, Qiang; Chen, Honghong

    2016-01-01

    The biodosimetric information is critical for evaluating the human health hazards caused by radon and its progeny. Here, we demonstrated that the formation of phosphorylated histone variant H2AX (γ-H2AX), p53-binding protein 1 (53BP1) and phosphorylated KRAB-associated protein 1 (pKAP-1) foci and their linear tracks in human peripheral blood lymphocytes (HPBLs) in vitro exposed to radon and its progeny were dependent on the cumulative absorbed dose of radon exposure but was unrelated to the concentration of radon. Among them, γ-H2AX foci and its linear tracks were the most sensitive indicators with the lowest estimable cumulative absorbed dose of 1.74 mGy from their linear dose-response curves and sustained for 12 h after termination of radon exposure. In addition, three types of foci showed an overdispersed non-Poisson distribution in HPBLs. The ratios of pKAP-1/γ-H2AX foci co-localization, 53BP1/γ-H2AX foci co-localization and 53BP1/pKAP-1 foci co-localization were significantly increased in HPBLs exposed to radon while they were unrelated to the cumulative dose of radon exposure, suggesting that γ-H2AX, pKAP-1 and 53BP1 play an important role in the repair of heterochromatic double-strand breaks. Altogether, our findings provide an experimental basis for estimating the biological dose of internal α-particle irradiation from radon and its progeny exposure in humans. PMID:27922110

  16. Development and validation of reverberation-chamber type whole-body exposure system for mobile-phone frequency.

    PubMed

    Jung, K B; Kim, T H; Kim, J L; Doh, H J; Chung, Y C; Choi, J H; Pack, J K

    2008-01-01

    We developed whole-body exposure systems for in-vivo study at cellular (848.5 MHz) and Personal Communication System (PCS, 1,762.5 MHz) frequency, utilizing reverberation chamber. The field uniformities in the test area of the designed chambers were verified by simulation and measurement. In the whole-body exposure environment, Specific Absorption Rate (SAR) distributions inside of mice were calculated using Finite Difference Time Domain (FDTD) simulation. Key results are presented in this article.

  17. A study on the correlation between soil radon potential and average indoor radon potential in Canadian cities.

    PubMed

    Chen, Jing; Ford, Ken L

    2017-01-01

    Exposure to indoor radon is identified as the main source of natural radiation exposure to the population. Since radon in homes originates mainly from soil gas radon, it is of public interest to study the correlation between radon in soil and radon indoors in different geographic locations. From 2007 to 2010, a total of 1070 sites were surveyed for soil gas radon and soil permeability. Among the sites surveyed, 430 sites were in 14 cities where indoor radon information is available from residential radon and thoron surveys conducted in recent years. It is observed that indoor radon potential (percentage of homes above 200 Bq m(-3); range from 1.5% to 42%) correlates reasonably well with soil radon potential (SRP: an index proportional to soil gas radon concentration and soil permeability; average SRP ranged from 8 to 26). In five cities where in-situ soil permeability was measured at more than 20 sites, a strong correlation (R(2) = 0.68 for linear regression and R(2) = 0.81 for non-linear regression) was observed between indoor radon potential and soil radon potential. This summary report shows that soil gas radon measurement is a practical and useful predictor of indoor radon potential in a geographic area, and may be useful for making decisions around prioritizing activities to manage population exposure and future land-use planning. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  18. Publications about Radon

    EPA Pesticide Factsheets

    There is no known safe level of exposure to radon. EPA strongly recommends that you fix your home if your test shows 4 picocuries (pCi/L) or more. These publications and resources will provide you with the information you need to fix your home.

  19. Researching Radon.

    ERIC Educational Resources Information Center

    Lucidi, Louis; Mecca, Peter M.

    2001-01-01

    Introduces a project in which students examined the physics, chemistry, and geology of radon and used available technology to measure radon concentrations in their homes. Uses the inquiry process, analytical skills, communication skills, content knowledge, and production of authentic products for student assessment. (YDS)

  20. Researching Radon.

    ERIC Educational Resources Information Center

    Lucidi, Louis; Mecca, Peter M.

    2001-01-01

    Introduces a project in which students examined the physics, chemistry, and geology of radon and used available technology to measure radon concentrations in their homes. Uses the inquiry process, analytical skills, communication skills, content knowledge, and production of authentic products for student assessment. (YDS)

  1. Radon-contaminated drinking water from private wells: an environmental health assessment examining a rural Colorado mountain community's exposure.

    PubMed

    Cappello, Michael Anthony; Ferraro, Aimee; Mendelsohn, Aaron B; Prehn, Angela Witt

    2013-11-01

    In the study discussed in this article, 27 private drinking water wells located in a rural Colorado mountain community were sampled for radon contamination and compared against (a) the U.S. Environmental Protection Agency's (U.S. EPA's) proposed maximum contaminant level (MCL), (b) the U.S. EPA proposed alternate maximum contaminate level (AMCL), and (c) the average radon level measured in the local municipal drinking water system. The data from the authors' study found that 100% of the wells within the study population had radon levels in excess of the U.S. EPA MCL, 37% were in excess of the U.S. EPA AMCL, and 100% of wells had radon levels greater than that found in the local municipal drinking water system. Radon contamination in one well was found to be 715 times greater than the U.S. EPA MCL, 54 times greater than the U.S. EPA AMLC, and 36,983 times greater than that found in the local municipal drinking water system. According to the research data and the reviewed literature, the results indicate that this population has a unique and elevated contamination profile and suggest that radon-contaminated drinking water from private wells can present a significant public health concern.

  2. Evaluation of automatic exposure control system chamber for the dose optimization when examining pelvic in digital radiography.

    PubMed

    Kim, Sung-Chul; Lee, Hae-Kag; Lee, Yang-Sub; Cho, Jae-Hwan

    2015-01-01

    We found a way to optimize the image quality and reduce the exposure dose of patients through the proper activity combination of the automatic exposure control system chamber for the dose optimization when examining the pelvic anteroposterior side using the phantom of the human body standard model. We set 7 combinations of the chamber of automatic exposure control system. The effective dose was yielded by measuring five times for each according to the activity combination of the chamber for the dose measurement. Five radiologists with more than five years of experience evaluated the image through picture archiving and communication system using double blind test while classifying the 6 anatomical sites into 3-point level (improper, proper, perfect). When only one central chamber was activated, the effective dose was found to be the highest level, 0.287 mSv; and lowest when only the top left chamber was used, 0.165 mSv. After the subjective evaluation by five panel members on the pelvic image was completed, there was no statistically meaningful difference between the 7 chamber combinations, and all had good image quality. When testing the pelvic anteroposterior side with digital radiography, we were able to reduce the exposure dose of patients using the combination of the top right side of or the top two of the chamber.

  3. Combination of geological data and radon survey results for radon mapping.

    PubMed

    Zhukovsky, Michael; Yarmoshenko, Ilia; Kiselev, Sergey

    2012-10-01

    The typical method of radon mapping usually used in most countries is the presenting of average radon concentrations in dwellings for districts or regions. Sometimes the maps of radon concentrations in the soil or maps of percentage above the reference level also demonstrated. Such approach not always can be used for identification of the regions with high probability of radon exposure above the reference levels where the population density is low. The combination of archive geological data and the results of representative radon survey allow estimating the typical parameters of radon concentration distribution for selected categories of buildings (multi-storey or rural type houses) situated in geological zones with the different radon potential. In this case it is possible to give grounds for the necessary level of radon protection measures in the new buildings constructed in this region. The use of such approach in Ural region of Russia is demonstrated. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Persistent nasal symptoms and mediator release after continuous pollen exposure in an environmental challenge chamber.

    PubMed

    Okuma, Yusuke; Okamoto, Yoshitaka; Yonekura, Syuji; Iinuma, Tomohisa; Sakurai, Toshioki; Hamasaki, Sawako; Ohki, Yuji; Yamamoto, Heizaburo; Sakurai, Daiju

    2016-08-01

    Immediate- and late-phase reactions are associated with nasal symptoms of patients with allergic rhinitis. To examine the symptoms and mediators released after continuous allergen exposure in an environmental challenge chamber (ECC). Fifteen patients with Japanese cedar pollinosis were enrolled in this study and continuously exposed to cedar pollen at a concentration of 8,000 grains/m(3) for 3 hours in an ECC. Nasal function tests were performed, and nasal secretions were collected before pollen exposure (0 hour), immediately after exiting the ECC (3 hours), and 6 hours after exiting the ECC (9 hours). Symptom scores were recorded every 30 minutes in the ECC and every 3 hours after exiting the ECC. The frequency of sneezing and nose blowing also was monitored. The severity of symptoms in the ECC peaked approximately 2 hours after the beginning of pollen exposure and continued more than 6 hours after leaving the ECC. Concentrations of histamine, tryptase, interleukins 5, 3, 33, and 31, and substance P increased over time, whereas that of nasal fractional exhaled nitric oxide decreased. Various mediators are released during continuous allergen exposure, which subsequently induce persistent nasal symptoms. Effective treatment is required to control the intense inflammation observed after allergen exposure. Copyright © 2016 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  5. Method for a homogeneous distribution of pollens in an environmental exposure chamber.

    PubMed

    Kenney, P; Bønløkke, J; Hilberg, O; Ravn, P; Schlünssen, V; Sigsgaard, T

    2016-09-01

    A variety of different environmental exposure chambers (EECs) have been used to evaluate treatments for allergic rhinitis. To describe and test a system for a homogenous distribution of grass pollen, Phleum Pratense, in an EEC to be used for controlled pollen exposure studies in allergic participants. A chamber made of stainless steel with completely rounded corners, seating four individuals at a time, was used. Room pressure, temperature, humidity and the air change rate were kept constant throughout the study period. A rotating pipette dispensed a uniform supply of pollen into a turntable's v-shaped grooves. A stainless steel capillary tube sucked the pollens into a venturi throat at which time the pollens were mixed with a high-pressure airstream of compressed high-efficiency particulate arrestance filtered air and then transported to a spreading plate inside the EEC. To achieve uniform concentrations in the EEC, the turntable's rotating speed was continuously adjusted using information from video-coupled feedback and feed forward mechanisms. Pollen levels were detected using standard volumetric air samplers and laser particle counters. The target pollen exposure level was 1000 pollens/m(3) . Twenty-one participants were exposed to pollens in the EEC twice for 210 min. Participants evaluated their symptoms every 30 min using a total nasal symptom score (TNSS) consisting of blocked nose, runny nose, nasal itching and sneezing. Across fifteen study days, the average pollen level was 982 pollens/m(3) (SD, 102 pollens/m(3) ). On average, participants experienced a 10% difference in overall pollen levels between their two visits to the EEC. The mean TNSSs rose throughout the exposure period, with a low at baseline of 0.43 (SD, 0.68) to a high of 4.71 (SD, 2.43) just before exiting the EEC. This EEC provides a reproducible, precise and homogenous distribution of pollens making it suitable for single-centre allergy clinical trials. © 2016 John Wiley & Sons Ltd.

  6. Amendments to the theory underlying Ussing chamber data of chloride ion secretion after bacterial enterotoxin exposure.

    PubMed

    Lucas, M L

    2005-05-07

    Bacterial enterotoxins may cause life-threatening diarrhoeal fluid loss in part because they stimulate enterocytes to secrete fluid into the small intestine as well as preventing normal fluid uptake. Abnormal chloride ion secretion is believed to provide the osmotic driving force for the inappropriate fluid movement. Evidence for enhanced chloride secretion consists of isotopic flux measurements in Ussing chambers, the standard apparatus for permeation studies. Flux from the lumen of the intestine is assumed to be determined solely by absorptive processes and flux towards the lumen solely by secretory processes. Bacterial enterotoxin increased flux towards the lumen is taken as an evidence of enhanced secretion. Examination of the flux equation solutions shows that the existing theoretical treatment of the Ussing chamber consists of the super-imposition of two contradictory unidirectional models. In contrast, the present analysis shows that a measured 'unidirectional' flux contains information both about absorptive and secretory processes, regardless of which flux is measured. Reciprocity is predicted for the fluxes, as decreases in the absorptive processes will cause increases in apparent secretory flux. Data from the literature show that mucosal-to-serosal chloride ion flux in rabbit ileum after exposure to secretagogues correlates inversely and highly significantly (r=0.74, n=17, p<0.001) with increases in serosal-to-mucosal chloride ion flux. As a category of evidence, flux data do not provide conclusive evidence of enhanced chloride secretion after exposure to enterotoxins, since an apparently enhanced serosal-to-mucosal flux would also be noted after inhibition of the mucosal-to-serosal flux. As interruption of absorptive processes can be misinterpreted as enhanced secretion in the Ussing chamber, this is a serious deficiency in the evidence for direct enterotoxin enhancement of the intestinal chloride ion channel as a basis for diarrhoeal disease.

  7. Radon exposure, cigarette smoking, and other mining experience in the beaverlodge uranium miners cohort

    SciTech Connect

    L'Abbe, K.A.; Howe, G.R.; Burch, J.D.; Miller, A.B.; Abbatt, J.; Band, P.; Choi, W.; Du, J.; Feather, J.; Gallagher, R. )

    1991-04-01

    A nested case-control study within the Beaverlodge Uranium Miners Cohort was undertaken to assess any possible contribution of confounding by smoking and other mining experience to the risk estimate derived from the original cohort study. Next of kin have been interviewed for 46 lung cancer cases and 95 controls enrolled in the Beaverlodge Uranium Miners Cohort Study who died between 1950 and 1980. Confounding by cigarette smoking and other mining experience appears unlikely to have contributed to the relative risk coefficient for exposure to Rn decay products derived in the parent study. Data for smoking and exposure to Rn decay products are consistent with a multiplicative model, although considerable caution must be applied to this interpretation.

  8. Methodology issues in risk assessment for radon.

    PubMed Central

    Harley, N H

    1991-01-01

    The alpha dose per unit radon daughter exposure in mines and homes is comparable at about 5 mGy/WLM. This means that excess lung cancer risk determined in follow-up studies of miners should be valid to extrapolating to environmental populations. There are several models currently used for risk projection to estimate lung cancer in the U.S. from indoor radon exposure. The accuracy of the estimates depends upon the quality of the exposure data and the models. Recent miner epidemiology confirms that excess lung cancer risk decreases with time subsequent to cessation of exposure. The most rigorous ecological study, to date, shows a persistent negative relationship between average measured indoor radon in U.S. counties and lung cancer mortality. A model for lung cancer risk is proposed that includes smoking, urbanization, and radon exposure. The model helps to explain the difficulties in observing the direct effects of indoor radon in the environment. PMID:2050058

  9. Assessment of inhalation and ingestion doses from exposure to radon gas using passive and active detecting techniques

    SciTech Connect

    Ismail, A. H.; Jafaar, M. S.

    2011-07-01

    The aim of this study was to assess an environmental hazard of radon exhalation rate from the samples of soil and drinking water in selected locations in Iraqi Kurdistan, passive (CR-39NTDs) and active (RAD7) detecting techniques has been employed. Long and short term measurements of emitted radon concentrations were estimated for 124 houses. High and lower radon concentration in soil samples was in the cities of Hajyawa and Er. Tyrawa, respectively. Moreover, for drinking water, high and low radon concentration was in the cities of Similan and Kelak, respectively. A comparison between our results with that mentioned in international reports had been done. Average annual dose equivalent to the bronchial epithelium, stomach and whole body in the cities of Kelak and Similan are estimated, and it was varied from 0.04{+-}0.01 mSv to 0.547{+-}0.018 mSv, (2.832{+-}0.22)x10{sup -5} to (11.972{+-}2.09)x10{sup -5} mSv, and (0.056 {+-}0.01) x10{sup -5} to (0.239{+-}0.01)x10{sup -5} mSv, respectively. This indicated that the effects of dissolved radon on the bronchial epithelium are much than on the stomach and whole body. (authors)

  10. B-type natriuretic peptide after open-water and hyperbaric chamber exposure to 10 msw.

    PubMed

    Grassi, Paolo; Stenner, Elisabetta; Rinaldi, Adriano; Delbello, Giorgio; Piccinini, Clara; Bussani, Andrea; Biancardi, Bruno; Biasioli, Bruno; Berlot, Giorgio

    2009-08-01

    Hyperbaric environment exposure in humans has cardiovascular effects mainly characterized by an increase in afterload and a decrease in cardiac output. In a previous study we did not find B-type natriuretic peptide (BNP) changes in healthy volunteers exposed to hyperbaric oxygen while other authors documented a significant increase in N-terminal pro-BNP after scuba diving. On the basis of these data we hypothesized that dry hyperbaric exposure and scuba diving could have different effects on BNP secretion. Nine healthy volunteers performed a 1-h open-sea air dive at 10 m depth (T); a few days later they were compressed in air in a hyperbaric chamber (CT) using the same dive profile. Three venous blood samples were drawn for each session: before starting the dives (T0 and CT0), immediately after exiting the water and the chamber (T1 and CT1), and 5 h later (T2 and CT2). A significant increase in plasma BNP was found with respect to baseline conditions after scuba diving both at T1 (median increment +32.69% [interquartile range +25.62 to +65.35%]) and at T2 (+28.03% [+23.08 to +38.92%]) while no differences were documented after the same dive in dry conditions either at CT1 (+1.34% [-17.57 to +33.55%]) or at CT2 (0.00% [17,67 to +21.62%]). These preliminary findings show that scuba diving and dry hyperbaric exposure, although at the same environmental pressure, cause different effects on ventricular loads in healthy subjects.

  11. Radon monitoring and hazard prediction in Ireland

    NASA Astrophysics Data System (ADS)

    Elio, Javier; Crowley, Quentin; Scanlon, Ray; Hodgson, Jim; Cooper, Mark; Long, Stephanie

    2016-04-01

    Radon is a naturally occurring radioactive gas which forms as a decay product from uranium. It is the largest source of natural ionizing radiation affecting the global population. When radon is inhaled, its short-lived decay products can interact with lung tissue leading to DNA damage and development of lung cancer. Ireland has among the highest levels of radon in Europe and eighth highest of an OECD survey of 29 countries. Every year some two hundred and fifty cases of lung cancer in Ireland are linked to radon exposure. This new research project will build upon previous efforts of radon monitoring in Ireland to construct a high-resolution radon hazard map. This will be achieved using recently available high-resolution airborne gamma-ray spectrometry (radiometric) and soil geochemistry data (http://www.tellus.ie/), indoor radon concentrations (http://www.epa.ie/radiation), and new direct measurement of soil radon. In this regard, legacy indoor radon concentrations will be correlated with soil U and Th concentrations and other geogenic data. This is a new approach since the vast majority of countries with a national radon monitoring programme rely on indoor radon measurements, or have a spatially limited dataset of soil radon measurements. Careful attention will be given to areas where an indicative high radon hazard based on geogenic factors does not match high indoor radon concentrations. Where such areas exist, it may imply that some parameter(s) in the predictive model does not match that of the environment. These areas will be subjected to measurement of radon soil gas using a combination of time averaged (passive) and time dependant (active) measurements in order to better understand factors affecting production, transport and accumulation of radon in the natural environment. Such mapping of radon-prone areas will ultimately help to inform when prevention and remediation measures are necessary, reducing the radon exposure of the population. Therefore, given

  12. Comparative survey of outdoor, residential and workplace radon concentrations

    PubMed Central

    Barros, Nirmalla; Field, Dan W.; Steck, Daniel J.; Field, R. William

    2015-01-01

    This study investigated radon concentrations in above-ground (i.e. first floor) workplace in Missouri and compared them with above-ground radon concentrations in nearby homes and outdoor locations. This study also examined the potential utility of using home and outdoor radon concentrations to predict the radon concentration at a nearby workplace (e.g. county agencies and schools). Even though workplace radon concentrations were not statistically different from home radon concentrations, the radon concentration at a particular home, or outdoor location, was a poor predictor of the radon concentration at a nearby workplace. Overall, 9.6 and 9.9 % of homes and workplace, respectively, exhibited radon concentrations of ≥148 Bq m−3. Because of the percentage of workplace with elevated radon concentrations, the results suggest that additional surveys of workplace radon concentrations are needed, especially in areas of high radon potential, to assess the contribution of workplace radon exposure to an individual's overall radon exposure. PMID:24936021

  13. Radon potential, geologic formations, and lung cancer risk

    PubMed Central

    Hahn, Ellen J.; Gokun, Yevgeniya; Andrews, William M.; Overfield, Bethany L.; Robertson, Heather; Wiggins, Amanda; Rayens, Mary Kay

    2015-01-01

    Objective Exposure to radon is associated with approximately 10% of U.S. lung cancer cases. Geologic rock units have varying concentrations of uranium, producing fluctuating amounts of radon. This exploratory study examined the spatial and statistical associations between radon values and geological formations to illustrate potential population-level lung cancer risk from radon exposure. Method This was a secondary data analysis of observed radon values collected in 1987 from homes (N = 309) in Kentucky and geologic rock formation data from the Kentucky Geological Survey. Radon value locations were plotted on digital geologic maps using ArcGIS and linked to specific geologic map units. Each map unit represented a package of different types of rock (e.g., limestone and/or shale). Log-transformed radon values and geologic formation categories were compared using one-way analysis of variance. Results Observed radon levels varied significantly by geologic formation category. Of the 14 geologic formation categories in north central Kentucky, four were associated with median radon levels, ranging from 8.10 to 2.75 pCi/L. Conclusion Radon potential maps that account for geologic factors and observed radon values may be superior to using observed radon values only. Knowing radon-prone areas could help target population-based lung cancer prevention interventions given the inequities that exist related to radon. PMID:26844090

  14. On the interaction between radon progeny and particles generated by electronic and traditional cigarettes

    NASA Astrophysics Data System (ADS)

    Vargas Trassierra, C.; Cardellini, F.; Buonanno, G.; De Felice, P.

    2015-04-01

    During their entire lives, people are exposed to the pollutants present in indoor air. Recently, Electronic Nicotine Delivery Systems, mainly known as electronic cigarettes, have been widely commercialized: they deliver particles into the lungs of the users but a "second-hand smoke" has yet to be associated to this indoor source. On the other hand, the naturally-occurring radioactive gas, i.e. radon, represents a significant risk for lung cancer, and the cumulative action of these two agents could be worse than the agents separately would. In order to deepen the interaction between radon progeny and second-hand aerosol from different types of cigarettes, a designed experimental study was carried out by generating aerosol from e-cigarette vaping as well as from second-hand traditional smoke inside a walk-in radon chamber at the National Institute of Ionizing Radiation Metrology (INMRI) of Italy. In this chamber, the radon present in air comes naturally from the floor and ambient conditions are controlled. To characterize the sidestream smoke emitted by cigarettes, condensation particle counters and scanning mobility particle sizer were used. Radon concentration in the air was measured through an Alphaguard ionization chamber, whereas the measurement of radon decay product in the air was performed with the Tracelab BWLM Plus-2S Radon daughter Monitor. It was found an increase of the Potential Alpha-Energy Concentration (PAEC) due to the radon decay products attached to aerosol for higher particle number concentrations. This varied from 7.47 ± 0.34 MeV L-1 to 12.6 ± 0.26 MeV L-1 (69%) for the e-cigarette. In the case of traditional cigarette and at the same radon concentration, the increase was from 14.1 ± 0.43 MeV L-1 to 18.6 ± 0.19 MeV L-1 (31%). The equilibrium factor increases, varying from 23.4% ± 1.11% to 29.5% ± 0.26% and from 30.9% ± 1.0% to 38.1 ± 0.88 for the e-cigarette and traditional cigarette, respectively. These growths still continue for long

  15. Intercomparison of retrospective radon detectors.

    PubMed Central

    Field, R W; Steck, D J; Parkhurst, M A; Mahaffey, J A; Alavanja, M C

    1999-01-01

    We performed both a laboratory and a field intercomparison of two novel glass-based retrospective radon detectors previously used in major radon case-control studies performed in Missouri and Iowa. The new detectors estimate retrospective residential radon exposure from the accumulation of a long-lived radon decay product, (210)Pb, in glass. The detectors use track registration material in direct contact with glass surfaces to measure the alpha-emission of a (210)Pb-decay product, (210)Po. The detector's track density generation rate (tracks per square centimeter per hour) is proportional to the surface alpha-activity. In the absence of other strong sources of alpha-emission in the glass, the implanted surface alpha-activity should be proportional to the accumulated (210)Po, and hence to the cumulative radon gas exposure. The goals of the intercomparison were to a) perform collocated measurements using two different glass-based retrospective radon detectors in a controlled laboratory environment to compare their relative response to implanted polonium in the absence of environmental variation, b) perform collocated measurements using two different retrospective radon progeny detectors in a variety of residential settings to compare their detection of glass-implanted polonium activities, and c) examine the correlation between track density rates and contemporary radon gas concentrations. The laboratory results suggested that the materials and methods used by the studies produced similar track densities in detectors exposed to the same implanted (210)Po activity. The field phase of the intercomparison found excellent agreement between the track density rates for the two types of retrospective detectors. The correlation between the track density rates and direct contemporary radon concentration measurements was relatively high, considering that no adjustments were performed to account for either the residential depositional environment or glass surface type

  16. Accounting for Berkson and Classical Measurement Error in Radon Exposure Using a Bayesian Structural Approach in the Analysis of Lung Cancer Mortality in the French Cohort of Uranium Miners.

    PubMed

    Hoffmann, Sabine; Rage, Estelle; Laurier, Dominique; Laroche, Pierre; Guihenneuc, Chantal; Ancelet, Sophie

    2017-02-01

    Many occupational cohort studies on underground miners have demonstrated that radon exposure is associated with an increased risk of lung cancer mortality. However, despite the deleterious consequences of exposure measurement error on statistical inference, these analyses traditionally do not account for exposure uncertainty. This might be due to the challenging nature of measurement error resulting from imperfect surrogate measures of radon exposure. Indeed, we are typically faced with exposure uncertainty in a time-varying exposure variable where both the type and the magnitude of error may depend on period of exposure. To address the challenge of accounting for multiplicative and heteroscedastic measurement error that may be of Berkson or classical nature, depending on the year of exposure, we opted for a Bayesian structural approach, which is arguably the most flexible method to account for uncertainty in exposure assessment. We assessed the association between occupational radon exposure and lung cancer mortality in the French cohort of uranium miners and found the impact of uncorrelated multiplicative measurement error to be of marginal importance. However, our findings indicate that the retrospective nature of exposure assessment that occurred in the earliest years of mining of this cohort as well as many other cohorts of underground miners might lead to an attenuation of the exposure-risk relationship. More research is needed to address further uncertainties in the calculation of lung dose, since this step will likely introduce important sources of shared uncertainty.

  17. Nonlinear dose-response relationship between radon exposure and the risk of lung cancer: evidence from a meta-analysis of published observational studies.

    PubMed

    Duan, Peng; Quan, Chao; Hu, Chunhui; Zhang, Jicai; Xie, Fei; Hu, Xiuxue; Yu, Zongtao; Gao, Bo; Liu, Zhixiang; Zheng, Hong; Liu, Changjiang; Wang, Chengmin; Yu, Tingting; Qi, Suqin; Fu, Wenjuan; Kourouma, Ansoumane; Yang, Kedi

    2015-07-01

    Although radon exposure (RE) has been confirmed to increase the risk of lung cancer (LC), questions remain about the shape of the dose-response relationship between RE and the risk of LC. We carried out a dose-response meta-analysis to investigate and quantify the potential dose-response association between residential and occupational exposure to radon and the risk of LC. All cohort and case-control studies published in English and Chinese on Embase, PubMed, and China National Knowledge Infrastructure (CNKI) digital databases through November 2013 were identified systematically. We extracted effect measures (relative risk, odds ratio, standardized mortality ratio, standardized incidence ratio, or standardized rate ratio) from individual studies to generate pooled results using meta-analysis approaches. We derived meta-analytic estimates using random-effects models taking into account the correlation between estimates. Restricted cubic splines and generalized least-squares regression methods were used to model a potential curvilinear relationship and to carry out a dose-response meta-analysis. Stratified analysis, sensitivity analysis, and assessment of bias were performed in our meta-analysis. Sixty publications fulfilling the inclusion criteria for this meta-analysis were finally included. Occupational RE was associated with LC [risk ratio 1.86, 95% confidence interval (CI)=1.67-2.09; I²=92.2%; 27 prospective studies], for pooled risk estimate of the: standardized mortality ratio [2.00 (95% CI=1.82-2.32)]; standardized incidence ratio [1.45 (95% CI=1.20-1.74)]; relative risk [2.10 (95% CI=1.64-2.69)]. In a subgroup analysis of uranium miners and residents exposed to occupational uranium, the summary risk was 2.23 (95% CI=1.86-2.68) and 1.23 (95% CI=1.05-1.44). The overall meta-analysis showed evidence of a nonlinear association between RE and the risk of LC (P(nonlinearity)<0.014); in addition, the point value of residential radon also improved the results

  18. A review on mathematical models for estimating indoor radon concentrations.

    PubMed

    Park, Ji Hyun; Kang, Dae Ryong; Kim, Jinheum

    2016-01-01

    Radiation from natural sources is one of causes of the environmental diseases. Radon is the leading environmental cause of lung cancer next to smoking. To investigate the relationship between indoor radon concentrations and lung cancer, researchers must be able to estimate an individual's cumulative level of indoor radon exposure and to do so, one must first be able to assess indoor radon concentrations. In this article, we outline factors affecting indoor radon concentrations and review related mathematical models based on the mass balance equation and the differential equations. Furthermore, we suggest the necessities of applying time-dependent functions for indoor radon concentrations and developing stochastic models.

  19. An exposure chamber for studies on human perception of DC electric fields and ions

    SciTech Connect

    Nguyen, D.H.; Maruvada, P.S. )

    1994-10-01

    Direct current (DC) transmission lines are often used, for technical and economic reasons, as interconnections in modern high voltage power systems, which are essentially of the alternating current (AC) type. Significant differences exist, however, between the field effects produced in the vicinity of AC and DC transmission lines. DC electric fields induce charges, on the surface of a conducting body such as a human being and may therefore be ''perceived'' by humans due to hair stimulation and other sensations experienced by the skin. A human being exposed to the ionized field of a DC transmission line experiences not only surface charges but also the conducted ion currents. A systematic laboratory study has been undertaken by Hydro Quebec to investigate human perception, using well established psycho physical techniques, of DC electric fields and ions. The design, construction and operation of an exposure chamber for this purpose, in the high voltage laboratory of IREQ, are described in this paper.

  20. Microbial ranking of porous packaging materials (exposure chamber method), ASTM method: collaborative study.

    PubMed

    Placencia, A M; Peeler, J T

    1999-01-01

    A collaborative study involving 11 laboratories was conducted to measure the microbial barrier effectiveness of porous medical packaging. Two randomly cut samples from each of 6 commercially available porous materials and one positive and one negative control were tested by one operator in each of 11 laboratories. Microbial barrier effectiveness was measured in terms of logarithm reduction value (LRV), which reflects the log10 microbial penetration of the material being tested. The logarithm of the final concentration is subtracted from that of the initial concentration to obtain the LRV. Thus the higher the LRV, the better the barrier. Repeatability standard deviations ranged from 6.42 to 16.40; reproducibility standard deviations ranged from 15.50 to 22.70. Materials B(53), C(50), D(CT), and E(45MF) differ significantly from the positive control. The microbial ranking of porous packaging materials (exposure chamber method), ASTM method, has been adopted First Action by AOAC INTERNATIONAL.

  1. Assessment and management of residential radon health risks: a report from the health Canada radon workshop.

    PubMed

    Tracy, Bliss L; Krewski, Daniel; Chen, Jing; Zielinski, Jan M; Brand, Kevin P; Meyerhof, Dorothy

    2006-04-01

    Epidemiologic studies of uranium miners and other underground miners have consistently shown miners exposed to high levels of radon to be at increased risk of lung cancer. More recently, concern has arisen about lung cancer risks among people exposed to lower levels of radon in homes. The current Canadian guideline for residential radon exposure was set in 1988 at 800 Bq/m(3). Because of the accumulation of a considerable body of new scientific evidence on radon lung cancer risks since that time, Health Canada sponsored a workshop to review the current state-of-the-science on radon health risks. The specific objectives of the workshop were (1) to collect and assess scientific information relevant to setting national radon policy in Canada, and (2) to gather information on social, political, and operational considerations in setting national policy. The workshop, held on 3-4 March 2004, was attended by 38 invited scientists, regulators, and other stakeholders from Canada and the United States. The presentations on the first day dealt primarily with scientific issues. The combined analysis of North American residential radon and lung cancer studies was reviewed. The analysis confirmed a small but detectable increase in lung cancer risk at residential exposure levels. Current estimates suggest that radon in homes is responsible for approximately 10% of all lung cancer deaths in Canada, making radon the second leading cause of lung cancer after tobacco smoking. This was followed by a perspective from an UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation) working group on radon. There were two presentations on occupational exposures to radon and two presentations considered the possibility of radon as a causative factor for cardiovascular disease and for cancer in other organs besides the lung. The possible contribution of environmental tobacco smoke to lung cancers in nonsmokers was also considered. Areas for future research were identified

  2. Radon concentration in drinking water and supplementary exposure in Baita-Stei mining area, Bihor county (Romania).

    PubMed

    Moldovan, Mircea; Nita, Dan Constantin; Cucos-Dinu, Alexandra; Dicu, Tiberius; Bican-Brisan, Nicoleta; Cosma, Constantin

    2014-03-01

    The radon concentration was measured in the drinking water of public water supply and private wells located in the mining area of BăiŢa-Ştei, Bihor County, Romania. The measurements were performed using the LUK-VR system based on radon gas measurement with Lucas cell. The results show that the radon concentrations are within the range of 1.9-134.3 kBq m(-3) with an average value of 35.5 kBq m(-3) for well water, 18.5 kBq m(-3) for spring water and 6.9 kBq m(-3) for tap water. Comparing with previous data from the whole of Transylvania, the average value is two times higher, proving this zone to be a radon-prone area. From the results of this study the effective dose to the population is between 4.78 and 338.43 µSv y(-1). These doses are within the recommended limits of the world organisations.

  3. Geogenic and anthropogenic impacts on indoor radon in the Techa River region.

    PubMed

    Yarmoshenko, I; Malinovsky, G; Vasilyev, A; Onischenko, A; Seleznev, A

    2016-11-15

    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.

  4. Methodology developed to make the Quebec indoor radon potential map.

    PubMed

    Drolet, Jean-Philippe; Martel, Richard; Poulin, Patrick; Dessau, Jean-Claude

    2014-03-01

    This paper presents a relevant approach to predict the indoor radon potential based on the combination of the radiogeochemical data and the indoor radon measurements in the Quebec province territory (Canada). The Quebec ministry of health asked for such a map to identify the radon-prone areas to manage the risk for the population related to indoor radon exposure. Three radiogeochemical criteria including (1) equivalent uranium (eU) concentration from airborne surface gamma-ray surveys, (2) uranium concentration measurements in sediments, (3) bedrock and surficial geology were combined with 3082 basement radon concentration measurements to identify the radon-prone areas. It was shown that it is possible to determine thresholds for the three criteria that implied statistically significant different levels of radon potential using Kruskal-Wallis one way analyses of variance by ranks. The three discretized radiogeochemical datasets were combined into a total predicted radon potential that sampled 98% of the studied area. The combination process was also based on Kruskal-Wallis one way ANOVA. Four statistically significant different predicted radon potential levels were created: low, medium, high and very high. Respectively 10 and 13% of the dwellings exceed the Canadian radon guideline of 200 Bq/m(3) in low and medium predicted radon potentials. These proportions rise up to 22 and 45% respectively for high and very high predicted radon potentials. This predictive map of indoor radon potential based on the radiogeochemical data was validated using a map of confirmed radon exposure in homes based on the basement radon measurements. It was shown that the map of predicted radon potential based on the radiogeochemical data was reliable to identify radon-prone areas even in zones where no indoor radon measurement exists.

  5. Measurement of Radon, Thoron, Isotopic Uranium and Thorium to Determine Occupational and Environmental Exposure and Risk at Fernald Feed Material Production Center

    SciTech Connect

    Harley, Naomi H.

    2002-10-31

    There are three basic research objectives. (1) To develop an accurate personal and area radon/thoron (222Rn/220Rn) detector for accurate measurement of the exposure to low airborne concentrations of these gases during remediation at Fernald. These are to be used to determine atmospheric dispersion and exposure to radon and thoron prior to and during retrieval and removal of the 4000 Ci of radium (226Ra) in the two silos at Fernald . (2) To develop a miniature personal (or area) aerosol particle size sampler that will operate continuously for weeks of continuous sampling under adverse conditions such as outdoors. Aerosol particle size is the major determinant of lung dose and without a measurement of the inhaled aerosol particle size accurate lung dosimetry cannot be obtained. No DOE site, with the exception of Fernald, is measuring the inhaled particle size spectrum for dosimetric purposes. (3) To develop the sequential radiochemistry necessary to measure any environmental sample (soil or water) for 228,230,232Th, 226,228Ra, 234,235,238U and 210Pb. To utilize the radiochemistry to accurately trace and delineate these nuclides in the environment.

  6. Long-term ozone exposure and ozone uptake of grapevines in open-top chambers

    NASA Astrophysics Data System (ADS)

    Soja, G.; Reichenauer, T. G.; Eid, M.; Soja, A.-M.; Schaber, R.; Gangl, H.

    Ozone uptake of pot-grown grapevines, fruit yield and sugar concentrations in juice were studied over the course of 4 years. In three of the study years, plants were exposed to contrasting ozone levels in open-top chambers. Results showed that juice quality was more sensitive to ozone exposure than grape yield. Ozone-induced reductions in grape yield were best described by the level of ozone exposure in the 2 years prior to harvest, whereas sugar content of juice was mainly affected by current and previous year ozone exposure. Regression models were developed to facilitate quantitative assessments of the effects of ozone on yield and quality. The observed effects on grape yield and on carbohydrate accumulation in fruit were slightly better explained when a threshold of 6 nmol m -2 s -1 was applied to cumulative uptake of ozone (CUO6) compared with AOT40 exposure or other CUO thresholds. Curvilinear regression models were developed which explained up to 75% of variance of the datasets. These models indicate a critical level of 1.1 mmol m -2 ozone (CUO6 from June to September) to protect carbohydrate accumulation in fruit with ozone taken up by the plants over consecutive years. For grape yield the CUO6 threshold was 2.2 mmol m -2 ozone. Exceedance of this threshold would be expected to reduce grape yield and sugar translocation to fruit by 10% with substantial degree of uncertainty (95% confidence interval 1-19%). For individual years, the critical level could be increased to 2.3 mmol m -2 for carbohydrate accumulation and 3.5 mmol m -2 CUO6 for grape yield if the CUO6 of 0 in the subsequent year was not exceeded.

  7. An improved scintillation cell for radon measurements

    NASA Astrophysics Data System (ADS)

    Quindos-Poncela, L. S.; Fernandez, P. L.; Sainz, C.; Arteche, J.; Arozamena, J. G.; George, A. C.

    2003-10-01

    Scintillation cells like "Modified Lucas cells" are widely used for grab-sample measurements of radon in the environment including those developed in the laboratory for evaluation of radon diffusion coefficients of radon barriers, radon emanation powers in small samples of porous materials and radon concentrations in small chambers used for different research studies. In this paper we describe the main characteristics of an improved and practical scintillation cell developed in our laboratory. Experimental efficiency values obtained for different cell volumes ranged between 0.038 and 0.123 cpm/Bq/m 3. The effects of atmospheric pressure on the detection efficiency as a function of the diameter of the cell were also studied. In general, a decrease of 15% was observed when increasing the pressure from 827 to 1013 hPa.

  8. Radon detection

    DOEpatents

    MacArthur, D.W.; Allander, K.S.; Bounds, J.A.

    1994-01-25

    A detector for atmospheric radon using a long range alpha detector as its sensing element is described. An electrostatic filter removes ions from ambient air, while allowing radon atoms to pass into a decay cavity. Here, radon atoms are allowed to decay, creating air ions. These air ions are drawn by a fan through a second electrostatic filter which can be activated or deactivated, and into the long range alpha detector. With the second electrostatic filter activated, no air ions are allowed to pass, and the signal output from the long range alpha detector consists of only the electronic background. With the second electrostatic filter deactivated, air ions and cosmic rays will be detected. The cosmic ray contribution can be minimized by shielding. 3 figures.

  9. Radon detection

    DOEpatents

    MacArthur, Duncan W.; Allander, Krag S.; Bounds, John A.

    1994-01-01

    A detector for atmospheric radon using a long range alpha detector as its sensing element. An electrostatic filter removes ions from ambient air, while allowing radon atoms to pass into a decay cavity. Here, radon atoms are allowed to decay, creating air ions. These air ions are drawn by a fan through a second electrostatic filter which can be activated or deactivated, and into the long range alpha detector. With the second electrostatic filter activated, no air ions are allowed to pass, and the signal output from the long range alpha detector consists of only the electronic background. With the second electrostatic filter deactivated, air ions and cosmic rays will be detected. The cosmic ray contribution can be minimized by shielding.

  10. Radon Measurements in Schools: An Interim Report.

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC. Office of Radiation Programs.

    Radon-222 is a colorless, odorless, tasteless, radioactive gas that occurs naturally in soil, rocks, underground water, and air. The United States Environmental Protection Agency (EPA) and other scientific organizations have identified an increased risk of lung cancer associated with exposure to elevated levels of radon in homes. Schools in many…

  11. Comparison study and thoron interference test of different radon monitors.

    PubMed

    Sumesh, C G; Kumar, A Vinod; Tripathi, R M; Puranik, V D

    2013-03-01

    A comparison study and thoron interference test for different continuous radon monitors were carried out. The comparison study includes three passive diffusion monitors [one pulse ionisation chamber based-Alpha Guard and two silicon semi-conductor based-Radon Scout Plus (RSP)] and one silicon semi-conductor-based active radon thoron discriminating monitor--RAD 7. Radon emanation standard, supplied by National Institute of Science and Technology, has been utilised for the comparison study to qualify the calibration of the continuous radon monitors. All the instruments showed good agreement with the estimated radon concentration using (226)Ra/(222)Rn emanation standard. It was found that the active radon monitoring system is having a higher initial response towards the transient radon concentration than the passive radon monitors studied. The instruments measuring radon concentration without energy discrimination are likely to have some sensitivity towards the thoron concentration. Thus, thoron interference study was carried out in the above monitors. Nine percent interference in measured radon concentration in the Alpha Guard monitor and 4 % interference in the semi-conductor-based RSP monitors was observed. Study indicates that the interference of thoron in radon monitors depends on the area of diffusion of gas, volume of detection and sensitivity factor.

  12. Responses to ragweed pollen in a pollen challenge chamber versus seasonal exposure identify allergic rhinoconjunctivitis endotypes.

    PubMed

    Jacobs, Robert L; Harper, Nathan; He, Weijing; Andrews, Charles P; Rather, Cynthia G; Ramirez, Daniel A; Ahuja, Sunil K

    2012-07-01

    The level of concordance between allergic symptoms induced on exposure to pollen in a pollen challenge chamber (PCC) versus the natural season is unknown. We sought to test the hypothesis that the symptom levels of allergic rhinoconjunctivitis elicited after out-of-season exposure to short ragweed in a PCC and during the natural season for giant ragweed pollen are highly correlated. Thirty-one ragweed-sensitive participants recorded symptoms for 15 days during the natural giant ragweed season in San Antonio, Texas. Twenty-six of these participants were challenged to short ragweed pollen in a PCC for 3 hours per day for up to 4 days. In the PCC participants were dichotomized into those in whom low versus high levels of symptoms developed slowly or rapidly (ie, slow/low vs rapid/high). Each successive exposure visit associated with a progressive increase in symptom levels that approximated those experienced during the natural season. Hierarchic clustering identified 3 endotypes: endotypes I and II reflected concordantly low (n= 7) versus high (n = 14) total symptom scores (TSSs) in both the natural season and the PCC, respectively. Accordingly, the correlation between the TSSs recorded in the natural season and in the PCC for these 21 participants was very high. Although participants with endotype III (n = 5) had greater TSSs in the natural season than in the PCC, the degree of correlation between the TSSs remained high. Our findings affirm our hypothesis, underscore the high cross-reactivity between distinct pollens, and highlight the utility of the PCC to identify novel allergy endotypes that might have contrasting mechanistic underpinnings and potentially therapeutic responses. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  13. Annual average indoor radon variations over two decades.

    PubMed

    Steck, D J

    2009-01-01

    Long-term exposure to elevated radon (222Rn) concentrations has been linked to increased lung cancer risk. Year-long measurements of contemporary radon concentrations have been the "gold standard" for epidemiologists trying to reconstruct past radon exposures and for homeowners trying to estimate future radon exposure. Random variations and persistent temporal trends can affect remedial action decisions and risk coefficients derived from epidemiological studies. Temporal fluctuations are possible when changes occur in a home's structure, climate, environment, or occupants. The annual-average temporal radon behavior was studied at 196 sites in 98 Minnesota houses. Seventeen hundred year-long indoor radon measurements were made from 1983 to 2000 to determine year-to-year radon fluctuations and long-term temporal trends. Ten year-long measurements over a span of 13 years were made at the typical site. The median radon concentration was 120 Bq m-3. The median radon concentration of the group of houses showed little year-to-year variation and no persistent temporal trends. At individual sites, year-to-year radon variations ranged from 3 to 110%. The median variation was 26%. Climate, exposure to wind, and radon concentration affected year-to-year variation, but house age, construction, or measurement floor did not. Some individual sites showed significantly larger radon changes when modifications were made to the house structure and heating-ventilation systems. Year-long radon measurements on the first floor provided better estimates of cumulative radon exposure than screening measurements. The radon variations observed in this study provide uncertainty estimates for year-long measurements that could help improve remediation decision protocols and refine risk estimates from epidemiological studies.

  14. The influence of multiple types of occupational exposure to radon, gamma rays and long-lived radionuclides on mortality risk in the French "post-55" sub-cohort of uranium miners: 1956-1999.

    PubMed

    Vacquier, Blandine; Rage, Estelle; Leuraud, Klervi; Caër-Lorho, Sylvaine; Houot, Jennifer; Acker, Alain; Laurier, Dominique

    2011-12-01

    The adverse health effects of radon on uranium miners, especially on their lungs, are well documented, but few studies have considered the effects of other radiation exposures. This study examined the mortality risks associated with exposure to radon, external γ rays and long-lived radionuclides (LLR) in the French "post-55" sub-cohort, which includes uranium miners first employed between 1956 and 1990 for whom all three types of exposure were assessed individually. Exposure-risk relationships were estimated with linear excess relative risk models and a 5-year lag time. The post-55 sub-cohort includes 3377 miners, contributing 89,405 person-years, followed up through the end of 1999 with a mean follow-up of 26.5 years. Mean cumulative exposure was 17.8 WLM for radon, 54.7 mSv for γ rays, and 1,632 Bq.m(-3).h for LLR. Among the 611 deaths observed, 66 were due to lung cancer. Annual individual exposures were significantly correlated. Increased mortality was observed for lung cancer (SMR = 1.30; 95% CI: 1.01, 1.65) and for brain and central nervous system (CNS) cancer (SMR = 2.00; 95% CI: 1.09, 3.35). Cumulative exposure to radon, γ rays and LLR was associated only with a significant risk of lung cancer. These new results could suggest an association between lung cancer and exposure to γ rays and LLR. They must nonetheless be interpreted with caution because of the correlation between the types of exposure. The calculation of organ doses received by each of these exposures would reduce the collinearity.

  15. Probing the application of Fourier Transform Infrared (FTIR) spectroscopy for assessment of deposited flux of Radon and Thoron progeny in high exposure conditions

    NASA Astrophysics Data System (ADS)

    Mishra, R.; Sapra, B. K.; Rout, R. P.; Prajith, R.

    2016-12-01

    Direct measurement of Radon and Thoron progeny in the atmosphere and occupational environments such as Uranium mines, Uranium and Thorium handling facilities has gained importance because of its radiological significance in inhalation dose assessment. In this regard, Radon and Thoron Progeny sensors (DTPS and DRPS) are the only passive solid state nuclear track detector (SSNTD, LR115) based devices which are being extensively used for time integrated direct progeny measurements. An essential component of the analysis is the chemical etching of the detectors, followed by spark counting of tracks and then estimation of the inhalation dose using appropriate calibration factors. Alternatively, the tracks may be counted using image analysis techniques. However, under high exposure conditions, both these methods have inherent limitations and errors arising due to increased frequency of tracks. In the present work, we probe the use of Fourier Transform Infra Red (FTIR) spectroscopy to analyse the deposited fluence of the progeny particulates based on change in transmittance of the nitric group vibrational bands of the LR115. A linear relationship between the transmittance and the deposited fluence was observed, which can be used to estimate the deposited fluence rate and the inhalation dose. This alternative method of analysis will provide a faster and non-destructive technique for inhalation dose assessment, specially for routine large scale measurements.

  16. Radon 222

    Integrated Risk Information System (IRIS)

    Radon 222 ; CASRN 14859 - 67 - 7 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinogenic Effec

  17. Managing Radon in Schools

    EPA Pesticide Factsheets

    EPA recommends testing all schools for radon. As part of an effective IAQ management program, schools can take simple steps to test for radon and reduce risks to occupants if high radon levels are found.

  18. On the exhalation rate of radon by man

    SciTech Connect

    Rundo, J.; Markun, F.; Plondke, N.J.

    1990-01-01

    This paper describes some aspects of the exhalation rate of radon by man which may be relevant to its internal dosimetry and, therefore, to possible radiobiological consequences. Prolonged exposure of a person to radon results in a reservoir or radon dissolved in body fat and fluids. If the person then moves to an environment with a lower radon concentration, there is a net exhalation of radon and the initial exhalation rate depends on the radon concentration in the first environment. This is demonstrated for seven persons whose houses contained radon at concentrations varying from 10 Bq m{sup {minus}3} to almost 1000 Bq m{sup {minus}3}. About one hour after leaving the house, the subjects' average exhalation rate of radon, expressed as the equivalent volume of house air per unit time, was 236 mL min{sup {minus}1}. 4 refs., 4 figs., 2 tabs.

  19. Test chamber exposure of humans to 1,6-hexamethylene diisocyanate and isophorone diisocyanate.

    PubMed

    Tinnerberg, H; Skarping, G; Dalene, M; Hagmar, L

    1995-01-01

    An isocyanate generation apparatus was developed and stable isocyanate atmospheres were obtained. At a concentration of 5 micrograms 1,6-hexamethylene diisocyanate (HDI) per m3 the precision was found to be 7% (n = 5). Three volunteers were each exposed to three different concentrations of HDI (11.9, 20.5, and 22.1 micrograms/m3) and three concentrations of isophorone diisocyanate (IPDI) (12.1, 17.7, and 50.7 micrograms/m3), in an exposure chamber. The duration of the exposure was 2 h. Urine and blood samples were collected, and hydrolysed under alkaline conditions to the HDI and IPDI corresponding amines, 1,6-hexamethylene diamine (HDA) and isophorone diamine (IPDA), determined as their pentafluoropropionic anhydride amides (HDA-PFPA and IPDA-PFPA). The HDA- and IPDA-PFPA derivatives were analysed using liquid chromatography mass spectrometry with thermospray monitoring negative ions. When working up samples from the exposed persons without hydrolysis, no HDA or IPDA was seen. The average urinary excretion of the corresponding amine was 39% for HDI and 27% for IPDI. An association between the estimated inhaled dose and the total excreted amount was seen. The average urinary elimination half-time for HDA was 2.5 h and for IPDA, 2.8 h. The hydrolysis condition giving the highest yield of HDA and IPDA in urine was found to be hydrolysis with 3 M sodium hydroxide during 4 h. No HDA or IPDA could be found in hydrolysed plasma (< ca 0.1 micrograms/l).

  20. Measurement of Radon, Thoron, Isotopic Uranium and Thorium to Determine Occupational and Environmental Exposure and Risk at Fernald Feed Material Production Center Publication Date: September 25, 2001

    SciTech Connect

    Harley, Naomi H.

    2001-09-25

    Research Objectives: (1) To develop an accurate personal radon/thoron monitor to quantitate exposure to low airborne concentrations before and during removal and relocation of radium from the silos. (2) To develop a personal aerosol particle size sampler, based on the principles of the novel sampler we have developed. The sampler measures not only 222Rn decay product aerosol size but long lived nuclides. There are, as yet, no particle size distribution data on the aerosol particle size distribution of these nuclides during remediation at any DOE site, although the aerosol particle size is the major determinant of lung dose. (3) To develop the sequential radiochemistry necessary to measure any environmental sample for 228,230,232Th, 226,228Ra, 234,235,238U and 210Pb. To utilize the radiochemistry and accurately trace and delineate these nuclides in the environment. To obtain historic and present radiochemical data to determine the need for supplemental soil/water etc., measurements.

  1. AN ALTERNATIVE CALIBRATION OF CR-39 DETECTORS FOR RADON DETECTION BEYOND THE SATURATION LIMIT.

    PubMed

    Franci, Daniele; Aureli, Tommaso; Cardellini, Francesco

    2016-12-01

    Time-integrated measurements of indoor radon levels are commonly carried out using solid-state nuclear track detectors (SSNTDs), due to the numerous advantages offered by this radiation detection technique. However, the use of SSNTD also presents some problems that may affect the accuracy of the results. The effect of overlapping tracks often results in the underestimation of the detected track density, which leads to the reduction of the counting efficiency for increasing radon exposure. This article aims to address the effect of overlapping tracks by proposing an alternative calibration technique based on the measurement of the fraction of the detector surface covered by alpha tracks. The method has been tested against a set of Monte Carlo data and then applied to a set of experimental data collected at the radon chamber of the Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti, at the ENEA centre in Casaccia, using CR-39 detectors. It has been proved that the method allows to extend the detectable range of radon exposure far beyond the intrinsic limit imposed by the standard calibration based on the track density. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Compilation of geogenic radon potential map of Pest County, Hungary

    NASA Astrophysics Data System (ADS)

    Szabó, K. Zs.; Pásztor, L.; Horváth, Á.; Bakacsi, Zs.; Szabó, J.; Szabó, Cs.

    2010-05-01

    222Rn and its effect on the human health have recently received major importance in environmental studies. This natural radioactive gas accounts for about 9% of lung cancer death and about 2% of all deaths from cancer in Europe due to indoor radon concentrations. It moves into the buildings from the natural decay chain of uranium in soils, rocks and building materials. Radon mapping regionalizes the average hazard from radon in a selected area as a radon risk map. Two major methods (concerning the applied radon data) have been used for mapping. One uses indoor radon data whereas the other is based on soil gas radon data. The outputs of the second approach are the geogenic radon potential maps. The principal objective of our work is to take the first step in geogenic radon mapping in Hungary. Soil samples collected in Pest County (Central Region of Hungary) in the frame of a countrywide soil survey (Soil Information and Monitoring System) were studied to have empirical information of the potential radon risk. As the first two steps radium concentration of soil samples, collected at 43 locations sampling soil profiles by genetic horizons from the surface level down to 60-150 cm, were determined using HPGe gamma-spectroscopy technique, as well as measurement of radon exhalation on the soil samples were carried out applying closed radon accumulation chamber coupled with RAD7 radon monitor detector. From these data the exhalation coefficient was calculated, which shows how many percent of the produced radon can come out from the sample. This rate strongly depends on the depth: at circa 100 cm a drastic decrease have been noticed, which is explained by the change in soil texture. The major source of indoor radon is the soil gas radon concentration (Barnet et al., 2005). We estimated this value from the measured radon exhalation and calculated soil porosity and density. The soil gas radon concentration values were categorized after Kemski et al. (2001) and then the

  3. Variation in residential radon levels in new Danish homes.

    PubMed

    Bräuner, E V; Rasmussen, T V; Gunnarsen, L

    2013-08-01

    Radon-222 gas arises from the radioactive decay of radium-226 and has a half-life of 3.8 days. This gas percolates up through soil into buildings, and if it is not evacuated, there can be much higher exposure levels indoors than outdoors, which is where human exposure occurs. Radon exposure is classified as a human carcinogen, and new Danish homes must be constructed to ensure indoor radon levels below 100 Bq/m(3). Our purpose was to assess how well 200 newly constructed single detached homes perform according to building regulations pertaining to radon and identify the association between indoor radon in these homes and municipality, home age, floor area, floor level, basement, and outer wall and roof construction. Median (5-95 percentile) indoor radon levels were 36.8 (9.0-118) Bq/m(3) , but indoor radon exceeded 100 Bq/m(3) in 14 of these new homes. The investigated variables explained nine percent of the variation in indoor radon levels, and although associations were positive, none of these were statistically significant. In this study, radon levels were generally low, but we found that 14 (7%) of the 200 new homes had indoor radon levels over 100 Bq/m(3). More work is needed to determine the determinants of indoor radon.

  4. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres

    SciTech Connect

    Hopke, P.K.

    1992-07-01

    This report describes studies on the chemical and physical behavior of the [sup 218]Po atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity in the sub-10 nm size range result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and its dose to the cells in the respiratory tract are to be fully assessed. The specific tasks of the controlled laboratory studies are to determine the formation rates of [center dot]OH radicals formed by the radiolysis of air following radon decay, to examine the formation of particles by the radiolytic oxidation of substances like SO[sub 2] ethylene, and H[sub 2]S to lower vapor pressure compounds and determine the role of gas phase additives such as H[sub 2]O and NH[sub 3] in determining the particle size, to measure the rate of ion-induced nucleation using a thermal diffusion cloud chamber, and to measure the neutralization rate of [sup 218]Po[sub x][sup +] in O[sub 2] at low radon concentrations. Tasks of the exposure studies in occupied indoor spaces are to initiate measurements of the activity size distributions in actual homes with occupants present so that the variability of the indoor activity size distributions can be assessed with respect to indoor aerosol sources and general lifestyle variations of the occupants, to initiate a prospective study of the utility of measurement of deposited [sup 210]Pb embedded in glass surfaces as a measure of the long-term, integrated exposure of the population to radon, and to develop the methodology to determine the hygroscopicity of the indoor aerosol so that the changes in deposition efficiency of the radioactive indoor aerosol with hygroscopic growth in the respiratory tract can be assessed.

  5. Radon, Smoking, and Lung Cancer: The Need to Refocus Radon Control Policy

    PubMed Central

    Mendez, David; Philbert, Martin A.

    2013-01-01

    Exposure to radon is the second leading cause of lung cancer, and the risk is significantly higher for smokers than for nonsmokers. More than 85% of radon-induced lung cancer deaths are among smokers. The most powerful approach for reducing the public health burden of radon is shaped by 2 overarching principles: public communication efforts that promote residential radon testing and remediation will be the most cost effective if they are primarily directed at current and former smokers; and focusing on smoking prevention and cessation is the optimal strategy for reducing radon-induced lung cancer in terms of both public health gains and economic efficiency. Tobacco control policy is the most promising route to the public health goals of radon control policy. PMID:23327258

  6. A reverberation chamber for rodents' exposure to wideband radiofrequency electromagnetic fields with different small-scale fading distributions.

    PubMed

    Li, Congsheng; Yang, Lei; Lu, Bingsong; Xie, Yi; Wu, Tongning

    2016-01-01

    A reverberation chamber (RC) is realized for the rodents' in vivo exposure to electromagnetic fields (EMFs) with various small-scale fading characteristics. Its performance is evaluated to ensure the exposure experiments from 0.85 to 2.60 GHz. By different configurations, line-of-sight and non-line-of-sight exposures can be established. The measured electric field in the RC is analyzed to determine its statistical distribution. We accordingly reconstruct the EMF environment by numerical methods. Simulations are carried to compare the dosimetric variability due to different small-scale fading characteristics. It demonstrates that the surveyed fading distribution will not change the specific absorption rate in the rats. The possibility to reproduce the realistic multi-reflective EMF environment by adjusting the structures of the RC is discussed. It is the first reported in vivo exposure system aiming to provide the EMF exposure with different small-scale fading distributions.

  7. Development and management of a radon assessment strategy suitable for underground railway tunnelling projects.

    PubMed

    Purnell, C J; Frommer, G; Chan, K; Auch, A A

    2004-01-01

    The construction of underground tunnels through radon-bearing rock poses a radiation health risk to tunnelling workers from exposure to radon gas and its radioactive decay products. This paper presents the development and practical application of a radon assessment strategy suitable for the measurement of radon in tunnelling work environments in Hong Kong. The assessment strategy was successfully evaluated on a number of underground railway tunnelling projects over a 3 y period. Radon measurements were undertaken using a combination of portable radon measurement equipment and track etch detectors (TEDs) deployed throughout the tunnels. The radon gas monitoring results were used to confirm that ventilation rates were adequate or identified, at an early stage, when further action to reduce radon levels was required. Exposure dose estimates based on the TED results showed that the exposure of tunnel workers to radon did not exceed 3 mSv per annum for the duration of each project.

  8. RADON REDUCTION AND RADON-RESISTANT CONSTRUCTION DEMONSTRATIONS IN NEW YORK - VOLUME 2: APPENDICES

    EPA Science Inventory

    Growing concern about health risks associated with exposure to indoor radon, a radioactive gas found in varying amounts in nearly all houses, has underscored the need for dependable radon reduction methods in existing and newly constructed houses. Responding to this need, the U....

  9. RADON REDUCTION AND RADON-RESISTANT CONSTRUCTION DEMONSTRATIONS IN NEW YORK - VOLUME 2: APPENDICES

    EPA Science Inventory

    Growing concern about health risks associated with exposure to indoor radon, a radioactive gas found in varying amounts in nearly all houses, has underscored the need for dependable radon reduction methods in existing and newly constructed houses. Responding to this need, the U....

  10. Computer controlled chamber measurements for clay adherence relevant for potential dioxin exposure through skin.

    PubMed

    Ferguson, Alesia; Bursac, Zoran; Johnson, Wayne; Davis, Jasmine

    2012-01-01

    A computer-controlled mechanical chamber was used to control the contact between aluminum sheet samples laden with clay, and cotton sheet samples for the measurement of mass transfer. The contact parameters of pressure (20 to 60 kPa) and time (10 to 70 sec) were varied for 160 multiple experiments of mass soil transfer. Before log transformation the average transfer for 'First Transfer' of clay particles was 34.4 ± 6.3 mg/8.97 cm(2) while that for 'Total Transfer' was 36.1 ± 6.8 mg/8.97 cm(2). Second contact, therefore, resulted in an average transfer of 1.70 ± 0.76 mg/8.97 cm(2). These values are well above adherence values measured for potting soil and sand as reported for previous experiments using the same methodologies. Based on the univariate analysis and the multiple regression analysis we were able to see some effect of parameters on the clay adherence values. The effect of pressure increases was significant for the higher levels of 50 and 60 kPa. In addition, we observed that increases in temperature were significant for 'First Transfer,' and less so for 'Total Transfer'. Past experiments using potting soil and play sand show high adherence values to human cadaver skin over cotton sample; the same scenario would be expected for clay. This data set can be used to improve estimates of dermal exposure to dioxins found in ball clays often used by artisans in the making of pottery.

  11. Radon Treatment Controversy

    PubMed Central

    Zdrojewicz, Zygmunt; Strzelczyk, Jadwiga (Jodi)

    2006-01-01

    In spite of long traditions, treatments utilizing radon-rich air or water have not been unequivocally embraced by modern medicine. The objective of this work is to examine factors that contribute to this continuing controversy. While the exact mechanism of radon's effect on human body is not completely understood, recent advances in radiobiology offer new insights into biochemical processes occurring at low-level exposures to ionizing radiation. Medical evidence and patients' testimonials regarding effectiveness of radon spa treatments of various ailments, most notably rheumatoid arthritis are accumulating worldwide. They challenge the premise of the Linear-No-Threshold (LNT) theory that the dose-effect response is the same per unit dose regardless of the total dose. Historically, such inference overshadowed scientific inquiries into the low-dose region and lead to a popular belief that no amount of radiation can be good. Fortunately, the LNT theory, which lacks any scientific basis, did not remain unchallenged. As the reviewed literature suggests, a paradigm shift, reflected in the consideration of hormetic effects at low-doses, is gaining momentum in the scientific community worldwide. The impetus comes from significant evidence of adaptive and stimulatory effects of low-levels of radiation on human immune system. PMID:18648641

  12. The assessment of radon/thoron ratio in Ukraine dwellings

    SciTech Connect

    Geets, V.I.; Varbanets, A.N.; Sorokobatkina, V.D.

    1995-12-31

    The main task of their work was the determination of radon/thoron ratio in air of dwellings for assessing thoron contribution to total individual dose of exposure to radon and thoron. The measurements of equivalent balance concentration (EBC) have been conducted by using radonometer (model 3S, Silena, Italy) for estimating a volume activity of short-lived radionuclides associated with radon/thoron semi-decay. The results obtained show that in the regions contaminated due to the Chernobyl accident depending on regional and residential peculiarities the average EBC value for radon in air of dwellings in 1992--1993 was ranged from 1.0 to 27.5 Bg/m{sup 3}, the EBC value for thoron (radon-220) -- from 0.15 to 8.6 Bq/m{sup 3}; radon/thoron ratio was equal to 1.1--17.4; and total average dose of exposure to radon -- from 0.31 to 2.69 mkZv/year. Their calculations show that a great correlation (correlation factor was recorded to be more that 0.52) between the EBC values for radon and thoron was registered in air of dwellings. In some cases thoron contribution (78.0%) to total individual exposure dose is greater that radon-contribution. Thus, when assessing exposure it is urgent to take into account not only the EBC value for radon but the EBC value for thoron, too.

  13. Development of the primary measurement standard for gaseous radon-222 activity.

    PubMed

    Kim, B C; Lee, K B; Park, T S; Lee, J M; Lee, S H; Oh, P J; Lee, M K; Ahn, J K

    2012-09-01

    The Korea Research Institute of Standards and Science (KRISS) has developed a primary system for the activity standardization of gaseous radon-222, based on the defined solid angle counting method. The size of adsorbed radon is determined by a Cyclone Storage Phosphor System, and a buffer chamber is introduced between the measurement chamber and the source for the purpose of gas purification. The measured activity of gaseous radon-222 and its associated measurement uncertainty obtained using the system are presented.

  14. Air cleaning and radon decay product mitigation

    SciTech Connect

    Hopke, P.K.; Li, C.S.; Ramamurthi, M.

    1990-12-31

    We evaluated air cleaning as a means to mitigate risks arising from exposure to indoor radon progeny in several single-family houses in the northeastern United States, using a new, automated, semi-continuous activity-weighted size distribution measurement system. Measurements included radon concentration, condensation nuclei count, and activity-weighted size distribution of radon decay products. Measurements were made with and without the air cleaning system operating. The influence of particles generated by various sources common to normal indoor activities on radon progeny behavior was evaluated. Aerosols were generated by running water in a shower, burning candles, smoking cigarettes, vacuuming, opening doors, and cooking. Both a filtration unit and an electrostatic precipitator were evaluated. Using a room model, the changes in attachment rates, average attachment diameters, and deposition rates of the ``unattached`` fraction with and without the air cleaning systems were calculated. The air cleaner typically reduced the radon progeny concentrations by 50 to 60%.

  15. Radon: implications for the health professional

    SciTech Connect

    Romano, C.A.

    1990-01-01

    Radon is a colorless, odorless gas formed by radioactive decay of radium and uranium, which are naturally present in the earth's crust. When concentrated indoors, this invisible gas becomes a potential health hazard. The Environmental Protection Agency estimates that up to 20,000 lung cancer deaths annually can be attributed to prolonged radon exposure. Radon is an important health issue that should be understood by all health care professionals. This paper discusses some of the important issues regarding radon, such as the incidences of lung cancer believed to be attributable to radon, the high-risk areas in the United States, federal safety guidelines, and public apathy. These issues and their impact on the health care required by professionals, especially nurse practitioners, are discussed.

  16. Air cleaning and radon decay product mitigation

    SciTech Connect

    Hopke, P.K. ); Li, C.S. . John B. Pierce Foundation Lab.); Ramamurthi, M. )

    1990-01-01

    We evaluated air cleaning as a means to mitigate risks arising from exposure to indoor radon progeny in several single-family houses in the northeastern United States, using a new, automated, semi-continuous activity-weighted size distribution measurement system. Measurements included radon concentration, condensation nuclei count, and activity-weighted size distribution of radon decay products. Measurements were made with and without the air cleaning system operating. The influence of particles generated by various sources common to normal indoor activities on radon progeny behavior was evaluated. Aerosols were generated by running water in a shower, burning candles, smoking cigarettes, vacuuming, opening doors, and cooking. Both a filtration unit and an electrostatic precipitator were evaluated. Using a room model, the changes in attachment rates, average attachment diameters, and deposition rates of the unattached'' fraction with and without the air cleaning systems were calculated. The air cleaner typically reduced the radon progeny concentrations by 50 to 60%.

  17. Mutagenicity of radon and radon daughters. Annual progress report

    SciTech Connect

    Evans, H.H.

    1991-12-01

    The objective of our research is to investigate the dose-response relationship of the lethal and mutagenic effects of exposure of cells to radon and its decay products. Dose rate dependence and the nature of the DNA lesion will be studied, using the thymidine kinase and HPRT loci to measure mutation frequency. A deficiency in DNA repair is shown to lead to a greater proportion of mutants with intergenic lesions. The cytotoxic effects of radon and its daughters are similar in human TK6 lymphoblasts and mouse L5178Y lymphoblasts, the cell line used in previous experiments. The results of molecular analysis of four spontaneous and 25 X-radiation induced HPRT{sup {minus}} mutants. Eleven radon-induced HPRT{sup {minus}} mutants have been isolated, and will be analyzed in a similar fashion. 9 figs.

  18. Granulation effects on the radon emanation rate.

    PubMed

    Bikit, I; Mrda, D; Grujic, S; Kozmidis-Luburic, U

    2011-05-01

    The radon emanation and the granulation effect on the emanation rate of several building materials (ceramic plates, sand, red brick and siporex brick) with different (226)Ra concentrations were investigated. A ball mill was used to achieve different granulations of the materials. The particle size distributions were determined by a particle size analyser (Mastersizer 2000). The increase in the (222)Rn concentration inside a closed chamber (volume ≈5.4 × 10(-3) m(3)) due to emanation from each material with different granulations was measured by an alpha spectrometer (RAD7). Thus, time-dependent curves for radon concentrations were obtained. The highest radon emanation coefficient (27 %) was obtained for the siporex sample with the smallest grain size (0.34 µm). For the ceramic pads, the granulation effect was negligible and the emanation coefficient was very low (∼0.4 %). The strongest influence of granulation on the radon emanation rate was found for the siporex brick sample.

  19. Optical detection of radon decay in air

    PubMed Central

    Sand, Johan; Ihantola, Sakari; Peräjärvi, Kari; Toivonen, Harri; Toivonen, Juha

    2016-01-01

    An optical radon detection method is presented. Radon decay is directly measured by observing the secondary radiolumines cence light that alpha particles excite in air, and the selectivity of coincident photon detection is further enhanced with online pulse-shape analysis. The sensitivity of a demonstration device was 6.5 cps/Bq/l and the minimum detectable concentration was 12 Bq/m3 with a 1 h integration time. The presented technique paves the way for optical approaches in rapid radon detec tion, and it can be applied beyond radon to the analysis of any alpha-active sample which can be placed in the measurement chamber. PMID:26867800

  20. Optical detection of radon decay in air.

    PubMed

    Sand, Johan; Ihantola, Sakari; Peräjärvi, Kari; Toivonen, Harri; Toivonen, Juha

    2016-02-12

    An optical radon detection method is presented. Radon decay is directly measured by observing the secondary radiolumines cence light that alpha particles excite in air, and the selectivity of coincident photon detection is further enhanced with online pulse-shape analysis. The sensitivity of a demonstration device was 6.5 cps/Bq/l and the minimum detectable concentration was 12 Bq/m(3) with a 1 h integration time. The presented technique paves the way for optical approaches in rapid radon detec tion, and it can be applied beyond radon to the analysis of any alpha-active sample which can be placed in the measurement chamber.

  1. Radon exhalation from sub-slab aggregate used in home construction in Canada.

    PubMed

    Bergman, Lauren; Lee, Jaeyoung; Sadi, Baki; Chen, Jing

    2015-06-01

    Exposure to elevated levels of radon in homes has been shown to result in an increased risk of developing lung cancer. The two largest contributors to indoor radon are radon in soil gas, formed from the rocks and soil surrounding the home, and building materials such as aggregate. This study measured the surface radon exhalation rates for 35 aggregate samples collected from producers across Canada. The radon exhalation rates ranged from 2.3 to 479.9 Bq m(-2) d(-1), with a mean of 80.7±112 Bq m(-2) d(-1). Using a simple, conservative analysis, the aggregate contribution to radon concentrations in an unfinished basement was determined. The maximum estimated radon concentration was 32.5±2.7 Bq m(-3), or ~16 % of the Canadian Radon Guideline. It can be concluded that under normal conditions radon exhalation from aggregate contributes very little to the total radon concentration in indoor air.

  2. Radon awareness and mitigation in Vermont: a public health survey.

    PubMed

    Riesenfeld, Erik P; Marcy, Theodore W; Reinier, Kyndaron; Mongeon, Joan A; Trumbo, Craig W; Wemple, Brian E; Kaminsky, David A

    2007-05-01

    Radon exposure is associated with an increased incidence of lung cancer, and elevated levels may be found in as many as 1 out of 15 homes. The U.S. EPA recommends testing homes for radon and mitigating over the advisory level of 4 picocuries per liter (4 pCi L(-1), or 148 Bq m(-3)). A sample population from a list of Vermont residents who had tested their residence for radon through the Vermont Department of Health and who had elevated levels were mailed a survey to assess demographic characteristics, knowledge about radon, mitigation rates, types of mitigation, as well as barriers to mitigation. The response rate was 63%. Forty-three percent of respondents mitigated. Roughly half were not completely knowledgeable of radon based upon the ability to associate radon exposure with lung cancer risk. Reasons not to mitigate radon levels in homes were cost and lack of concern over elevated levels. A multivariate logistic regression analysis revealed factors associated with mitigating: an education level of college or higher (p = 0.02), concern that a high radon level would affect real estate value (p = 0.04), and home age less than 10 y (p = 0.05). In summary, less than half of Vermonters with elevated radon levels participating in the Department of Health program mitigated. We identify factors associated with radon mitigation that may lead to improved radon education and mitigation practice.

  3. Study of Natural Radioactivity, Radon Exhalation Rate and Radiation Doses in Coal and Flyash Samples from Thermal Power Plants, India

    NASA Astrophysics Data System (ADS)

    Singh, Lalit Mohan; Kumar, Mukesh; Sahoo, B. K.; Sapra, B. K.; Kumar, Rajesh

    Coal is one of the most important source used for electrical power generation. Its combustion part known as fly ash is used in the manufacturing of bricks, sheets, cement, land filling etc. Coal and its by-products have significant amounts of radionuclide's including uranium, thorium which is the ultimate source of the radioactive gas radon and thoron respectively. Radiation hazard from airborne emissions of coal-fired power plants have been cited as possible causes of health in environmental. Assessment of the radiation exposure from coal burning is critically dependent on the concentration of radioactive elements in coal and in the fly ash. In the present study, samples of coal and flyash were collected from Rajghat Power Plant and Badarpur Thermal Power Plant, New Delhi, India. Radon exhalation is important parameter for the estimation of radiation risk from various materials. Solis State Nuclear Track Detector based sealed Can Technique (using LR-115 type II) has been used for measurement radon exhalation rate. Also accumulation chamber based Continuous Radon Monitor and Continuous Thoron Monitor have been used for radon masss exhalation and thoron surface exhalation rate respectively. Natural radioactivity has been measured using a low level NaI(Tl) detector based on gamma ray spectrometry.

  4. Radon Risk Communication Strategies: A Regional Story.

    PubMed

    Cheng, Winnie

    2016-01-01

    Risk communication on the health effects of radon encounters many challenges and requires a variety of risk communication strategies and approaches. The concern over radon exposure and its health effects may vary according to people's level of knowledge and receptivity. Homeowners in radon-prone areas are usually more informed and have greater concern over those not living in radon-prone areas. The latter group is often found to be resistant to testing. In British Columbia as well as many other parts of the country, some homes have been lying outside of the radon-prone areas have radon levels above the Canadian guideline, which is the reason Health Canada recommends that all homes should be tested. Over the last five years, the Environment Health Program (EHP) of Health Canada in the British Columbia region has been using a variety of different approaches in their radon risk communications through social media, workshops, webinars, public forums, poster contests, radon distribution maps, public inquiries, tradeshows and conference events, and partnership with different jurisdictions and nongovernmental organizations. The valuable lessons learned from these approaches are discussed in this special report.

  5. Experimental, statistical, and biological models of radon carcinogenesis

    SciTech Connect

    Cross, F.T.

    1991-09-01

    Risk models developed for underground miners have not been consistently validated in studies of populations exposed to indoor radon. Imprecision in risk estimates results principally from differences between exposures in mines as compared to domestic environments and from uncertainties about the interaction between cigarette-smoking and exposure to radon decay products. Uncertainties in extrapolating miner data to domestic exposures can be reduced by means of a broad-based health effects research program that addresses the interrelated issues of exposure, respiratory tract dose, carcinogenesis (molecular/cellular and animal studies, plus developing biological and statistical models), and the relationship of radon to smoking and other copollutant exposures. This article reviews experimental animal data on radon carcinogenesis observed primarily in rats at Pacific Northwest Laboratory. Recent experimental and mechanistic carcinogenesis models of exposures to radon, uranium ore dust, and cigarette smoke are presented with statistical analyses of animal data. 20 refs., 1 fig.

  6. A Radon Progeny Deposition Model

    SciTech Connect

    Guiseppe, V. E.; Elliott, S. R.; Hime, A.; Rielage, K.; Westerdale, S.

    2011-04-27

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly {sup 222}Rn) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of {sup 210}Pb on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean room environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to deposit radon progeny on various surfaces under a controlled environment in order to develop a deposition model. Results from this test stand and the resulting deposition model are presented.

  7. A radon progeny deposition model

    SciTech Connect

    Rielage, Keith; Elliott, Steven R; Hime, Andrew; Guiseppe, Vincente E; Westerdale, S.

    2010-12-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly {sup 222}Rn) and its subsequent progeny present in an experiment are potential backgrounds, also problematic is the deposition of radon progeny on detector materials. Exposure to radon at any stage of assembly of an experiment can result in surface contamination by progeny supported by the long half life (22 y) of {sup 210}Pb on sensitive locations of a detector. An understanding of the potential surface contamination from deposition will enable requirements of radon-reduced air and clean room environments for the assembly of low background experiments. It is known that there are a number of environmental factors that govern the deposition of progeny onto surfaces. However, existing models have not explored the impact of some environmental factors important for low background experiments. A test stand has been constructed to deposit radon progeny on various surfaces under a controlled environment in order to develop a deposition model. Results from this test stand and the resulting deposition model are presented.

  8. Canadian population risk of radon induced lung cancer: a re-assessment based on the recent cross-Canada radon survey

    PubMed Central

    Chen, J.; Moir, D.; Whyte, J.

    2012-01-01

    Exposure to indoor radon has been determined to be the second leading cause of lung cancer after tobacco smoking. Canadian population risk of radon induced lung cancer was assessed in 2005 with the radon distribution characteristics determined from a radon survey carried out in the late 1970s in 19 cities. In that survey, a grab sampling method was used to measure radon levels. The observed radon concentration in 14 000 Canadian homes surveyed followed a log–normal distribution with a geometric mean (GM) of 11.2 Bq m–3 and a geometric standard deviation (GSD) of 3.9. Based on the information from that survey, it was estimated that ∼10 % of lung cancers in Canada resulted from indoor radon exposure. To gain a better understanding of radon concentrations in homes across the country, a national residential radon survey was launched in April 2009. In the recent survey, long-term (3 month or longer) indoor radon measurements were made in roughly 14 000 homes in 121 health regions across Canada. The observed radon concentrations follow, as expected, a log–normal distribution with a GM of 41.9 Bq m–3 and a GSD of 2.8. Based on the more accurate radon distribution characteristics obtained from the recent cross-Canada radon survey, a re-assessment of Canadian population risk for radon induced lung cancer was undertaken. The theoretical estimates show that 16 % of lung cancer deaths among Canadians are attributable to indoor radon exposure. These results strongly suggest the ongoing need for the Canadian National Radon Program. In particular, there is a need for a focus on education and awareness by all levels of government, and in partnership with key stakeholders, to encourage Canadians to take action to reduce the risk from indoor radon exposure. PMID:22874897

  9. Application of the can technique and radon gas analyzer for radon exhalation measurements.

    PubMed

    Fazal-ur-Rehman; Al-Jarallah, M I; Musazay, M S; Abu-Jarad, F

    2003-01-01

    A passive "can technique" and an active radon gas analyzer with an emanation container were applied for radon exhalation rate measurements from different construction materials, viz. five marble seven ceramic and 100 granite tiles used in Saudi Arabia. The marble and ceramic tiles did not show detectable radon exhalation using the active radon gas analyzer system. However the granite tiles showed relatively high radon exhalations, indicating a relatively high uranium content. A comparison of the radon exhalation rates measured by the two techniques showed a linear correlation coefficient of 0.57. The radon exhalation rates from the granites varied from 0.02 to 6.58 Bqm(-2)h(-1) with an average of 1.35+/-1.40 Bqm(-2)h(-1). The geometric mean and the geometric standard deviation of the frequency distribution were found to be 0.80 and 3.1, respectively. The track density found on the nuclear track detectors in the can technique exposed to the granites, having high exhalation rates, varied linearly with exposure time with a linear correlation coefficient of 0.99. This experimental finding agrees with the theoretical prediction. The can technique showed sensitivity to low radon exhalation rates from ceramic, marble and some granite over a period of 2 months, which were not detectable by the active radon gas analyzer system. The reproducibility of data with both measuring techniques was found to be within a 7% deviation.

  10. Nanomaterial containing wall paints can increase radon concentration in houses located in radon prone areas.

    PubMed

    Haghani, M; Mortazavi, S M J; Faghihi, R; Mehdizadeh, S; Moradgholi, J; Darvish, L; Fathi-Pour, E; Ansari, L; Ghanbar-Pour, M R

    2013-09-01

    Nowadays, extensive technological advancements have made it possible to use nanopaints which show exciting properties. In IR Iran excessive radon levels (up to 3700 Bq m-3) have been reported in homes located in radon prone areas. Over the past decades, concerns have been raised about the risk posed by residential radon exposure. This study aims at investigating the effect of using nanomaterial containing wall paints on radon concentration in homes. Two wooden model houses were used in this study. Soil samples from Ramsar high background radiation areas were used for simulating the situation of a typical house in radon-prone areas. Conventional water-soluble wall paint was used for painting the walls of the 1st house model; while the 2nd house model was painted with the same wall paint with montmorillonitenanoclay. Three days after sealing the house models, radon level was measured by using a portable radon survey meter. The mean radon level inside the 1st house model (conventional paint) was 515.3 ± 17.8 Bq/m(3) while the mean radon concentration in the 2nd house model (nano-painted house model) was 570.8 ± 18.5 Bq/m(3). The difference between these means was statistically significant (P<0.001). To the best of our knowledge, this study is the first investigation on the effect of nano-material containing wall paints on indoor radon concentrations.  It can be concluded that nano-material-containing wall paints should not be used in houses with wooden walls located in radon prone areas. Although the mechanism of this effect is not clearly known, decreased porosity in nano-paints might be a key factor in increasing the radon concentration in homes.

  11. Nanomaterial Containing Wall Paints Can Increase Radon Concentration in Houses Located in Radon Prone Areas

    PubMed Central

    Haghani, M.; Mortazavi, S. M. J.; Faghihi, R.; Mehdizadeh, S.; Moradgholi, J.; Darvish, L.; Fathi-Pour, E.; Ansari, L.; Ghanbar-pour, M. R.

    2013-01-01

    Background: Nowadays, extensive technological advancements have made it possible to use nanopaints which show exciting properties. In IR Iran excessive radon levels (up to 3700 Bq m–3) have been reported in homes located in radon prone areas. Over the past decades, concerns have been raised about the risk posed by residential radon exposure. Objective: This study aims at investigating the effect of using nanomaterial containing wall paints on radon concentration in homes. Methods: Two wooden model houses were used in this study. Soil samples from Ramsar high background radiation areas were used for simulating the situation of a typical house in radon-prone areas. Conventional water-soluble wall paint was used for painting the walls of the 1st house model; while the 2nd house model was painted with the same wall paint with montmorillonitenanoclay. Results: Three days after sealing the house models, radon level was measured by using a portable radon survey meter. The mean radon level inside the 1st house model (conventional paint) was 515.3 ± 17.8 Bq/m3 while the mean radon concentration in the 2nd house model (nano-painted house model) was 570.8 ± 18.5 Bq/m3. The difference between these means was statistically significant (P<0.001). Conclusion: To the best of our knowledge, this study is the first investigation on the effect of nano-material containing wall paints on indoor radon concentrations.  It can be concluded that nano-material-containing wall paints should not be used in houses with wooden walls located in radon prone areas. Although the mechanism of this effect is not clearly known, decreased porosity in nano-paints might be a key factor in increasing the radon concentration in homes. PMID:25505754

  12. Consumer's Guide to Radon Reduction

    MedlinePlus

    ... provide feedback, or report a problem. Radon Indoor Air Quality Home Page Radon Home Local Radon Zones and State Contact Information Individuals and Families Radon Publications Home Buyers and ... Air Bed Bugs Chemicals and Toxics Climate Change Environmental ...

  13. Management of radon: a review of ICRP recommendations.

    PubMed

    Vaillant, Ludovic; Bataille, Céline

    2012-09-01

    This article proposes a review of past and current ICRP publications dealing with the management of radon exposures. Its main objective is to identify and discuss the driving factors that have been used by the Commission during the last 50 years so as to better appreciate current issues regarding radon exposure management. The analysis shows that major evolutions took place in very recent years. As far as the management of radon exposures is concerned, ICRP recommended, until ICRP Publication 103 (ICRP 2007 ICRP Publication 103; Ann. ICRP 37), to use action levels and to consider only exposures above these levels. The Commission has reviewed its approach and now proposes to manage any radon exposure through the application of the optimisation principle and associated reference levels. As far as the assessment of the radon risk is concerned, it appears that the successive changes made by ICRP did not have a strong impact on the values of radon gas concentration recommended as action levels either in dwellings or in workplaces. The major change occurred in late 2009 with the publication of the ICRP Statement on Radon, which acknowledged that the radon risk has been underestimated by a factor of 2, thus inducing a major revision of radon reference levels.

  14. Performance of the first Japanese large-scale facility for radon inhalation experiments with small animals.

    PubMed

    Ishimori, Yuu; Mitsunobu, Fumihiro; Yamaoka, Kiyonori; Tanaka, Hiroshi; Kataoka, Takahiro; Sakoda, Akihiro

    2011-07-01

    A radon test facility for small animals was developed in order to increase the statistical validity of differences of the biological response in various radon environments. This paper illustrates the performances of that facility, the first large-scale facility of its kind in Japan. The facility has a capability to conduct approximately 150 mouse-scale tests at the same time. The apparatus for exposing small animals to radon has six animal chamber groups with five independent cages each. Different radon concentrations in each animal chamber group are available. Because the first target of this study is to examine the in vivo behaviour of radon and its effects, the major functions to control radon and to eliminate thoron were examined experimentally. Additionally, radon progeny concentrations and their particle size distributions in the cages were also examined experimentally to be considered in future projects.

  15. Optimization of the Timepix chip to measurement of radon, thoron and their progenies.

    PubMed

    Janik, Miroslaw; Ploc, Ondrej; Fiederle, Michael; Procz, Simon; Kavasi, Norbert

    2016-01-01

    Radon and thoron as well as their short-lived progenies are decay products of the radium and thorium series decays. They are the most important radionuclide elements with respect to public exposure. To utilize the semiconductor pixel radiation Timepix chip for the measurement of active and real-time alpha particles from radon, thoron and their progenies, it is necessary to check the registration and visualization of the chip. An energy check for radon, thoron and their progenies, as well as for (241)Am and(210)Po sources, was performed using the radon and thoron chambers at NIRS (National Institute of Radiological Sciences). The check found an energy resolution of 200 keV with a 14% efficiency as well as a linear dependency between the channel number (cluster volume) and the energy. The coefficient of determination r(2) of 0.99 for the range of 5 to 9 MeV was calculated. In addition, an offset for specific Timepix configurations between pre-calibration for low energy from 6 to 60 keV, and the actual calibration for alpha particles with energies from 4000 to 9000 keV, was detected.

  16. Simplified modeling for infiltration and radon entry

    SciTech Connect

    Sherman, M.H.

    1992-08-01

    Air leakage in the envelopes of residential buildings is the primary mechanism for provided ventilation to those buildings. For radon the same mechanisms that drive the ventilation, drive the radon entry This paper attempts to provide a simplified physical model that can be used to understand the interactions between the building leakage distribution, the forces that drive infiltration and ventilation, and indoor radon concentrations, Combining both ventilation and entry modeling together allows an estimation of Radon concentration and exposure to be made and demonstrates how changes in the envelope or ventilation system would affect it. This paper will develop simplified modeling approaches for estimating both ventilation rate and radon entry rate based on the air tightness of the envelope and the driving forces. These approaches will use conventional leakage values (i.e. effective leakage area ) to quantify the air tightness and include natural and mechanical driving forces. This paper will introduce a simplified parameter, the Radon Leakage Area, that quantifies the resistance to radon entry. To be practical for dwellings, modeling of the occupant exposures to indoor pollutants must be simple to use and not require unreasonable input data. This paper presents the derivation of the simplified physical model, and applies that model to representative situations to explore the tendencies to be expected under different circumstances.

  17. Carcinogenic and Cocarcinogenic Effects of Radon and Radon Daughters in Rats.

    PubMed Central

    Monchaux, G; Morlier, JP; Morin, M; Chameaud, J; Lafuma, J; Masse, R

    1994-01-01

    It has been previously established that lung cancer could be induced in rats by exposure to radon and radon daughters. Although the oat-cell carcinomas that are common in humans were not found in rats, other histological types of lung carcinomas, especially squamous cell carcinomas and primitive lung adenocarcinomas, were similar to those observed in humans. A dose-effect relationship was established for cumulative doses varying from 25 to 3000 working-level-months (WLM), which was similar for medium and high cumulative doses to that observed in uranium miners. This experimental protocol was also used to study the potential cocarcinogenic effects of other environmental or industrial airborne pollutants such as tobacco smoke, mineral fibers, diesel exhausts, or minerals from metallic mine ores that may act synergistically with radon exposure. In rats exposed to radon and tobacco smoke combined, the incidence of lung cancers was higher by a factor of 2-4 according to the cumulative radon exposure and the duration of tobacco smoke exposure. When mineral fibers were injected intrapleurally, an increased incidence of malignant thoracic tumors was observed in rats exposed to radon and fibers combined, but synergistic effects resulted in additivity. With diesel exhausts or minerals from metallic ores, a slight, nonsignificant increase in the incidence of lung carcinomas was observed compared with rats exposed to radon alone. These results demonstrated that it is possible to establish the potential cocarcinogenic action, showing either multiplicative, additive, or no effect of various environmental or industrial airborne pollutants combined with radon exposure. This radon model is valid for investigating possible interactions between two occupational exposures. Images p64-a Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. PMID:9719670

  18. Dosimetry of inhaled radon and thoron progeny

    SciTech Connect

    James, A.C.

    1994-06-01

    This chapter reviews recent developments in modeling doses received by lung tissues, with particular emphasis on application of ICRP`s new dosimetric model of the respiratory tract for extrapolating to other environments the established risks from exposure to radon progeny in underground mines. Factors discussed include: (1) the influence of physical characteristics of radon progeny aerosols on dose per unit exposure, e.g., the unattached fraction, and the activity-size distributions of clustered and attached progeny; (2) the dependence of dose on breathing rate, and on the exposed subject (man, woman or child); (3) the variability of dose per unit exposure in a home when exposure is expressed in terms of potential {alpha} energy or radon gas concentration; (4) the comparative dosimetry of thoron progeny; and (5) the effects of air-cleaning on lung dose. Also discussed is the apparent discrepancy between lung cancer risk estimates derived purely from dosimetry and the lung cancer incidence observed in the epidemiological studies of radon-exposed underground miners. Application of ICRP`s recommended risk factors appears to overestimate radon lung-cancer risk for miners by a factor of three. ``Normalization`` of the calculated effective dose is therefore needed, at least for {alpha} dose from radon and thoron progeny, in order to obtain a realistic estimate of lung cancer risk.

  19. The role of the implementation of policies for the prevention of exposure to Radon in Brazil—a strategy for controlling the risk of developing lung cancer

    PubMed Central

    Lino, Aline da Rocha; Abrahão, Carina Meira; Amarante, Marcus Paulo Fernandes; de Sousa Cruz, Marcelo Rocha

    2015-01-01

    Lung cancer is the leading cause of cancer death in the United States and other industrialised countries. The most important risk factor is active smoking. However, given the increased incidence of lung cancer in non-smokers, it is necessary to improve knowledge regarding other risk factors. Radon (Rn) is a noble gas and is the most important natural source of human exposure to ionizing radiation. Exposure to high levels of this radioactive gas is related to an increased risk of developing lung cancer. The objective of this work is to highlight the importance of measuring indoor concentration of this gas and identify which steps should be taken for achieving radiological protection. A survey was conducted on the websites of the National Health Surveillance Agency (ANVISA), LAMIN (Mineral Analysis Laboratory), CPRM (Geological Survey of Brazil), Ministry of Health and PubMed. Using the words ‘radon’, ‘lung’, ‘cancer’, and PubMed®, 1,371 results were obtained; when using the words ‘radon’, ‘lung’, ‘cancer’, and with ‘Brazil’ or ‘Brazilians’, only six results were obtained. We emphasise that lung cancer is a major public health problem and the exposure to Rn indoors should be considered as a risk factor for lung cancer in non-smokers. Buildings or houses with high concentrations of Rn should be identified. However, currently in Brazil—a country with great potential for mineral extraction—there are no specific regulated recommendations to control indoor exposure to Rn. PMID:26435745

  20. Measuring Leukocyte Adhesion to (Primary) Endothelial Cells after Photon and Charged Particle Exposure with a Dedicated Laminar Flow Chamber

    PubMed Central

    Erbeldinger, Nadine; Rapp, Felicitas; Ktitareva, Svetlana; Wendel, Philipp; Bothe, Anna S.; Dettmering, Till; Durante, Marco; Friedrich, Thomas; Bertulat, Bianca; Meyer, Stephanie; Cardoso, M. C.; Hehlgans, Stephanie; Rödel, Franz; Fournier, Claudia

    2017-01-01

    The vascular endothelium interacts with all types of blood cells and is a key modulator of local and systemic inflammatory processes, for example, in the adhesion of blood leukocytes to endothelial cells (EC) and the following extravasation into the injured tissue. The endothelium is constantly exposed to mechanical forces caused by blood flow, and the resulting shear stress is essential for the maintenance of endothelial function. Changes in local hemodynamics are sensed by EC, leading to acute or persistent changes. Therefore, in vitro assessment of EC functionality should include shear stress as an essential parameter. Parallel-plate flow chambers with adjustable shear stress can be used to study EC properties. However, commercially available systems are not suitable for radiation experiments, especially with charged particles, which are increasingly used in radiotherapy of tumors. Therefore, research on charged-particle-induced vascular side effects is needed. In addition, α-particle emitters (e.g., radon) are used to treat inflammatory diseases at low doses. In the present study, we established a flow chamber system, applicable for the investigation of radiation induced changes in the adhesion of lymphocytes to EC as readout for the onset of an inflammatory reaction or the modification of a pre-existing inflammatory state. In this system, primary human EC are cultured under physiological laminar shear stress, subjected to a proinflammatory treatment and/or irradiation with X-rays or charged particles, followed by a coincubation with primary human lymphocytes (peripheral blood lymphocytes (PBL)). Analysis is performed by semiautomated quantification of fluorescent staining in microscopic pictures. First results obtained after irradiation with X-rays or helium ions indicate decreased adhesion of PBL to EC under laminar conditions for both radiation qualities, whereas adhesion of PBL under static conditions is not clearly affected by irradiation. Under static

  1. Multagenicity of radon and radon daughters. Final technical report, January 1, 1993--December 31, 1996

    SciTech Connect

    Evans, H.H.

    1997-06-01

    The objective of this research was to investigate the dose-response relationship with regard to the lethal and mutagenic effects of exposure of cells to radon and its decay products. Dose-rate dependence was studied, as well as the nature of the DNA lesions. The effect of DNA repair on the lethal and mutagenic effects of exposure and on the character of the DNA lesions was investigated by comparing the response of L5178Y strains that differ in their ability to rejoin X radiation-induced DNA double strand breaks. The nature of radon/radon daughter-induced mutational lesions in human lymphoblasts was also investigated.

  2. Contamination of individuals by radon daughters: a preliminary study

    SciTech Connect

    Stebbings, J.H.; Dignam, J.J.

    1988-03-01

    Body radon daughter contamination reflects relative individual respiratory exposures to radon daughters; counts can be related both to household radon levels and to lung cancer risk factors such as sex and tobacco smoking. Radon daughters were counted by gamma spectroscopy from 180 adult residents of eastern Pennsylvania. A seven-position, 35-min scan was conducted in a mobile body counter, generally during afternoon or evening hours. Track-etch detectors for household radon were distributed, and were recovered from 80% of the subjects. Over 75% of the population had environmentally enhanced radon daughter contamination. House radon levels were strongly related, as anticipated, to radon daughter contamination in the 112 subjects for whom both sets of measurements were available (p less than .001); basement measurements were as strongly related to personal contamination as were living area measurements; bedroom measurements were slightly more strongly correlated. Both sex (p less than .02) and cigarette smoking (p less than .01) significantly modified the relationships, after nonlinear adjustment for travel times. Using a logarithmic model, a given house living-area radon level was associated in females with body contamination by radon daughters 2-3 times that in males. Nonsmokers had 2-4 times higher levels of contamination than smokers. Results are for the total of internal and external contamination, these being highly correlated in preliminary experiments. Time usage and activity patterns of the subjects are believed to be important in explaining these findings, and may become important variables in radon risk assessment.

  3. A novel algorithm for quick and continuous tracing the change of radon concentration in environment

    NASA Astrophysics Data System (ADS)

    Tan, Yanliang; Xiao, Detao

    2011-04-01

    Several measurements of the radon concentration are performed by RAD7 in the University of South China. We find that 30-40 min is needed for RAD7 for tracing the concentration of the standard radon chamber. There are two reasons. The first is that the sufficient time of air cycle is needed for the radon concentration in internal cell of RAD7 equal to that of the environment; and the second is that the sufficient decay time is needed for the 218Po concentration in internal cell of RAD7 equal to that of the radon. We used a zeroth order approximation to describe the evolution of the environment radon concentration, and obtained a novel algorithm for quick and continuous tracing the change of radon concentration. The corrected radon concentration obtained through this method is in good agreement with the reference value. This method can be applied to develop and improve the instruments for tracing the change of radon concentration quickly.

  4. Identification of Surrogate Measures of Diesel Exhaust Exposure in a Controlled Chamber Study

    EPA Science Inventory

    Exposure to diesel exhaust (DE) has been associated with acute cardiopulmonary and vascular responses, chronic noncancer health effects, and respiratory cancers in humans. To better understand DE exposures and eventually their related health effects, we established a controlled c...

  5. Identification of Surrogate Measures of Diesel Exhaust Exposure in a Controlled Chamber Study

    EPA Science Inventory

    Exposure to diesel exhaust (DE) has been associated with acute cardiopulmonary and vascular responses, chronic noncancer health effects, and respiratory cancers in humans. To better understand DE exposures and eventually their related health effects, we established a controlled c...

  6. Differences in aerosolization of Rift Valley fever virus resulting from choice of inhalation exposure chamber: implications for animal challenge studies

    PubMed Central

    Bethel, Laura M.; Powell, Diana S.; Caroline, Amy L.; Hartman, Amy L.

    2014-01-01

    Abstract The aerosol characteristics of Rift Valley fever virus (RVFV) were evaluated to achieve reproducible infection of experimental animals with aerosolized RVFV suitable for animal efficacy studies. Spray factor (SF), the ratio between the concentrations of the aerosolized agent to the agent in the aerosol generator, is used to compare performance differences between aerosol exposures. SF indicates the efficiency of the aerosolization process; a higher SF means a lower nebulizer concentration is needed to achieve a desired inhaled dose. Relative humidity levels as well as the duration of the exposure and choice of exposure chamber all impacted RVFV SF. Differences were also noted between actual and predicted minute volumes for different species of nonhuman primates. While NHP from Old World species (Macaca fascicularis, M. mulatta, Chlorocebus aethiops) generally had a lower actual minute volume than predicted, the actual minute volume for marmosets (Callithrix jacchus) was higher than predicted (150% for marmosets compared with an average of 35% for all other species examined). All of these factors (relative humidity, chamber, duration, and minute volume) impact the ability to reliably and reproducibly deliver a specific dose of aerosolized RVFV. The implications of these findings for future pivotal efficacy studies are discussed. PMID:24532259

  7. [The development of the ionization chamber and the researching of its characteristics for automatic exposure controlling in the X-ray diagnosis machine].

    PubMed

    Weng, P; Liu, S; Wang, H; Cao, Y; Wang, X; Li, Y

    1999-01-01

    An ionization chamber for automatic exposure controlling used in X ray diagnosis machine was developped, and its characteristics were measured and researched. The electrodes of measuring field were made of carbon, such couldn't leave it's imaging on the film. In order to increase the ionization efficiency and decrease the thickness and electric capacity between electrodes, the chamber was constructed in multilayers. The chamber we developed can be fixed in different x ray machines convenientlly, there is a fine linearity between it's signal output and the exposures, the beam quality response is uniform and output-timing response is also good.

  8. Spatial indoor radon distribution in Mexico City.

    PubMed

    Franco-Marina, Francisco; Villalba-Caloca, Jaime; Segovia, Nuria; Tavera, Leticia

    2003-12-30

    We present a spatial analysis of residential radon concentrations in the Mexico City Metropolitan Area, which we intend to use to assign radon exposure in an ongoing case-control study. As part of a probabilistic household survey, carried out between May and June 1999, 501 dwellings were selected for indoor placement of solid state nuclear track detectors (LR 115) in a cup array over a period of approximately 90 days. As part of the sampling design, the city was grid partitioned into nine zones and a sample of dwellings was selected in each zone. All zones were simultaneously surveyed. The stratified sampling design allowed us to obtain radon geometric means, adjusted for household characteristics, week of detector placement and number of days of measurement for these zones. Additionally, adjusted geometric means were estimated for the 100 census tracts surveyed and this information was used to obtain a more detailed spatial distribution of residential radon levels through kriging interpolation and surface contouring. Radon levels depended on the room of placement, the floor level and the ventilation habits but not on building materials. Regarding the city zone, the highest adjusted geometric mean was found in the southwest (136 Bqm(-3)), where 46% of the households had an estimated radon level in excess of 200 Bqm(-3). In the rest of the city, the geometric mean concentration ranged between 41 and 98 Bqm(-3). A more detailed spatial distribution showed that, in general, most of the eastern and middle zones of the city had estimated radon geometric means below 74 Bqm(-3), while the western ones had geometric means above this concentration. Very high geometric means, exceeding 111 Bqm(-3) and even reaching 288 Bqm(-3), are estimated for some areas located in the southern and western zones of Mexico City. The obtained spatial distribution shows that the areas with very high estimated residential radon concentrations are close to inactive volcanic mountains. We

  9. STUDY OF RADIATION EXPOSURE DUE TO RADON, THORON AND THEIR PROGENY IN THE INDOOR ENVIRONMENT OF RAJPUR REGION OF UTTARAKHAND HIMALAYA.

    PubMed

    Kandari, Tushar; Aswal, Sunita; Prasad, Mukesh; Pant, Preeti; Bourai, A A; Ramola, R C

    2016-10-01

    In the present study, the measurements of indoor radon, thoron and their progeny concentrations have been carried out in the Rajpur region of Uttarakhand, Himalaya, India by using LR-115 solid-state nuclear track detector-based time-integrated techniques. The gas concentrations have been measured by single-entry pin-hole dosemeter technique, while for the progeny concentrations, deposition-based Direct Thoron and Radon Progeny Sensor technique has been used. The radiation doses due to the inhalation of radon, thoron and progeny have also been determined by using obtained concentrations of radon, thoron and their progeny in the study area. The average radon concentration varies from 75 to 123 Bq m(-3) with an overall average of 89 Bq m(-3) The average thoron concentration varies from 29 to 55 Bq m(-3) with an overall average of 38 Bq m(-3) The total annual effective dose received due to radon, thoron and their progeny varies from 2.4 to 4.1 mSv y(-1) with an average of 2.9 mSv y(-1) While the average equilibrium factor for radon and its progeny was found to be 0.39, for thoron and its progeny, it was 0.06. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Development of a dose-controlled multiculture cell exposure chamber for efficient delivery of airborne and engineered nanoparticles

    NASA Astrophysics Data System (ADS)

    Asimakopoulou, Akrivi; Daskalos, Emmanouil; Lewinski, Nastassja; Riediker, Michael; Papaioannou, Eleni; Konstandopoulos, Athanasios G.

    2013-04-01

    In order to study the various health influencing parameters related to engineered nanoparticles as well as to soot emitted by Diesel engines, there is an urgent need for appropriate sampling devices and methods for cell exposure studies that simulate the respiratory system and facilitate associated biological and toxicological tests. The objective of the present work was the further advancement of a Multiculture Exposure Chamber (MEC) into a dose-controlled system for efficient delivery of nanoparticles to cells. It was validated with various types of nanoparticles (Diesel engine soot aggregates, engineered nanoparticles for various applications) and with state-of-the-art nanoparticle measurement instrumentation to assess the local deposition of nanoparticles on the cell cultures. The dose of nanoparticles to which cell cultures are being exposed was evaluated in the normal operation of the in vitro cell culture exposure chamber based on measurements of the size specific nanoparticle collection efficiency of a cell free device. The average efficiency in delivering nanoparticles in the MEC was approximately 82%. The nanoparticle deposition was demonstrated by Transmission Electron Microscopy (TEM). Analysis and design of the MEC employs Computational Fluid Dynamics (CFD) and true to geometry representations of nanoparticles with the aim to assess the uniformity of nanoparticle deposition among the culture wells. Final testing of the dose-controlled cell exposure system was performed by exposing A549 lung cell cultures to fluorescently labeled nanoparticles. Delivery of aerosolized nanoparticles was demonstrated by visualization of the nanoparticle fluorescence in the cell cultures following exposure. Also monitored was the potential of the aerosolized nanoparticles to generate reactive oxygen species (ROS) (e.g. free radicals and peroxides generation), thus expressing the oxidative stress of the cells which can cause extensive cellular damage or damage on DNA.

  11. Development of a System to Perform, Record, and Analyze Measurements of Radon Concentrations on a Large Scale.

    DTIC Science & Technology

    1990-10-01

    rate of radon gas through air is much higher than through water. Strong and Levins measured the emanation rate of radon gas from columns of uranium mill...19 passive detectors attempt to average the radon concentrations * over longer periods. Ionization chambers are large metal containers, generally...floor which separates the interior from the crawl space is only wooden planks, and does not provide an airtight seal. Thus radon emanating out of the

  12. The Impact of Declining Smoking on Radon-Related Lung Cancer in the United States

    PubMed Central

    Alshanqeety, Omar; Warner, Kenneth E.; Lantz, Paula M.; Courant, Paul N.

    2011-01-01

    Objectives. We examined the effect of current patterns of smoking rates on future radon-related lung cancer. Methods. We combined the model developed by the National Academy of Science's Committee on Health Risks of Exposure to Radon (the BEIR VI committee) for radon risk assessment with a forecasting model of US adult smoking prevalence to estimate proportional decline in radon-related deaths during the present century with and without mitigation of high-radon houses. Results. By 2025, the reduction in radon mortality from smoking reduction (15 percentage points) will surpass the maximum expected reduction from remediation (12 percentage points). Conclusions. Although still a genuine source of public health concern, radon-induced lung cancer is likely to decline substantially, driven by reductions in smoking rates. Smoking decline will reduce radon deaths more that remediation of high-radon houses, a fact that policymakers should consider as they contemplate the future of cancer control. PMID:21228294

  13. Health effects from radon-222 in drinking water in Algiers.

    PubMed

    Amrani, D; Cherouati, D E

    1999-09-01

    As part of a national programme, 222Rn in public water supply systems, private wells and in natural mineral waters has been measured in some locations of Algiers City. Radon concentration was determined by means of a passive method based on the use of electret ion chambers (EIC). The determination of radon concentration in the water samples consisted of sealing a known volume of water in a jar and measuring the airborne radon using an E-PERM (electret-passive environmental radon monitor) device. The radon concentrations in natural mineral waters were found to be the highest of all other water samples. It is found that the mean radon concentration of water samples was lower than the value of 11000 Bq m(-3) (11 Bq l(-1)) reported by the US Environmental Protection Agency. These investigations enabled a first estimate of the corresponding annual effective dose to the stomach and the lungs. It was observed that the annual effective dose resulting from direct consumption of water is far greater than that due to inhalation of radon emanating from tap water. Moreover, it is also shown that the annual effective dose due to inhalation of radon emanating from tap water and flushing water is negligible compared to the total annual dose for indoor radon in Algiers.

  14. Radon in Schools

    MedlinePlus

    ... cannot ignore this problem." Kathryn Whitfill, National PTA President. The EPA ranks indoor radon among the most ... our children demands no less. Keith Geiger, NEA President. Top of Page Radon gas decays into radioactive ...

  15. Radon: A health problem

    SciTech Connect

    Pucci, J.; Gaston, S.

    1990-01-01

    Nurses can and should function as effective teachers about the potential hazards to health of radon contamination in the home as well as become activists in the development of health care policy on radon.

  16. Radon Guide for Tenants

    EPA Pesticide Factsheets

    This guide is for people who rent their apartments or houses. The guide explains what radon is, and how to find out if there is a radon problem in your home. The guide also talks about what you can do if there are high radon levels in your home.

  17. Allergen exposure chambers: harmonizing current concepts and projecting the needs for the future - an EAACI Position Paper.

    PubMed

    Pfaar, O; Calderon, M A; Andrews, C P; Angjeli, E; Bergmann, K C; Bønløkke, J H; de Blay, F; Devillier, P; Ellis, A K; Gerth van Wijk, R; Hohlfeld, J M; Horak, F; Jacobs, R L; Jacobsen, L; Jutel, M; Kaul, S; Larché, M; Larenas-Linnemann, D; Mösges, R; Nolte, H; Patel, P; Peoples, L; Rabin, R L; Rather, C; Salapatek, A M; Sigsgaard, T; Thaarup, S; Yang, J; Zieglmayer, P; Zuberbier, T; Demoly, P

    2017-07-01

    Allergen exposure chambers (AECs) are clinical facilities allowing for controlled exposure of subjects to allergens in an enclosed environment. AECs have contributed towards characterizing the pathophysiology of respiratory allergic diseases and the pharmacological properties of new therapies. In addition, they are complementary to and offer some advantages over traditional multicentre field trials for evaluation of novel therapeutics. To date, AEC studies conducted have been monocentric and have followed protocols unique to each centre. Because there are technical differences among AECs, it may be necessary to define parameters to standardize the AECs so that studies may be extrapolated for driving basic immunological research and for marketing authorization purposes by regulatory authorities. For this task force initiative of the European Academy of Allergy and Clinical Immunology (EAACI), experts from academia and regulatory agencies met with chamber operators to list technical, clinical and regulatory unmet needs as well as the prerequisites for clinical validation. The latter covered the validation process, standardization of challenges and outcomes, intra- and interchamber variability and reproducibility, in addition to comparability with field trials and specifics of paediatric trials and regulatory issues. This EAACI Position Paper aims to harmonize current concepts in AECs and to project unmet needs with the intent to enhance progress towards use of these facilities in determining safety and efficacy of new therapeutics in the future. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Controlling the Radon Threat Needn't Be Another Costly Nightmare.

    ERIC Educational Resources Information Center

    Freije, Matthew R.

    1989-01-01

    After a study of 3,000 classrooms in 130 schools in 16 states, the Environmental Protection Agency urged all schools to conduct tests for radon. Explains a 6-step screening test, methods of reducing radon concentrations, and how the risk from radon exposure compares with other risks. (MLF)

  19. Controlling the Radon Threat Needn't Be Another Costly Nightmare.

    ERIC Educational Resources Information Center

    Freije, Matthew R.

    1989-01-01

    After a study of 3,000 classrooms in 130 schools in 16 states, the Environmental Protection Agency urged all schools to conduct tests for radon. Explains a 6-step screening test, methods of reducing radon concentrations, and how the risk from radon exposure compares with other risks. (MLF)

  20. Radon and climatic multiparameter analysis: A one-year study on radon dynamics in a house

    SciTech Connect

    Genrich, V.

    1995-12-31

    Radon-reduction in private and public buildings is a current issue. Research has opened our eyes for the enormous fluctuations of the indoor radon level over longer observation periods. For generalizing the behavior radon in a building, care must be taken that the observation period is long enough, to mediate the pronounced climatic changes in the course of a year. The author has started a one-year observations, precisely logging up the radon level in a single family home. Six portable multiparameter-monitors, each equipped with a 0.6 liter PIC-detector (PIC = pulse ionization chamber), have been installed at different locations within the building and outdoors (incl. two soil-gas probes). Besides the radon concentration, in the same instruments the following parameters are logged cotinuously: relative humidity, differential pressure between basement and sub-slab area, soil impendance (indication water saturation) and wind speed on the roof. In the basement, the radon concentration varies between 61 Bq/m{sup 3} and 5408 Bq/m{sup 3} (mean: 1092 Bq/m{sup 3}.) By analyzing these records, the time sequence of the radon concentration can be characterized as a {open_quotes}mixture{close_quotes} of (periodic) circadian variations overlayed with (aperiodic) seasonal fluctuations. In this building, it turns out, that the pressure difference across the base plate is an important factor for radon entry as well as ventilation rate. It can be shown, that the pressure is closely related to the indoor-outdoor temperature difference. This relation was found to be non-linear. Other factors are attributed to the activities of the inhabitants. The paper points out correlations between radon and different climatic parameters mainly by using scatterplots and classical regression methods.

  1. A COMPARISON OF WINTER SHORT-TERM AND ANNUAL AVERAGE RADON MEASUREMENTS IN BASEMENTS OF A RADON-PRONE REGION AND EVALUATION OF FURTHER RADON TESTING INDICATORS

    PubMed Central

    Barros, Nirmalla G.; Steck, Daniel J.; Field, R. William

    2014-01-01

    The primary objective of this study was to investigate the temporal variability between basement winter short-term (7 to 10 days) and basement annual radon measurements. Other objectives were to test the short-term measurement’s diagnostic performance at two reference levels and to evaluate its ability to predict annual average basement radon concentrations. Electret ion chamber (short-term) and alpha track (annual) radon measurements were obtained by trained personnel in Iowa residences. Overall, the geometric mean of the short-term radon concentrations (199 Bq m−3) was slightly greater than the geometric mean of the annual radon concentrations (181 Bq m−3). Short-term tests incorrectly predicted that the basement annual radon concentrations would be below 148 Bq m−3 12% of the time and 2% of the time at 74 Bq m−3. The short-term and annual radon concentrations were strongly correlated (r=0.87, p<0.0001). The foundation wall material of the basement was the only significant factor to have an impact on the absolute difference between the short-term and annual measurements. The findings from this study provide evidence of a substantially lower likelihood of obtaining a false negative result from a single short-term test in a region with high indoor radon potential when the reference level is lowered to 74 Bq m−3. PMID:24670901

  2. A comparison of winter short-term and annual average radon measurements in basements of a radon-prone region and evaluation of further radon testing indicators.

    PubMed

    Barros, Nirmalla G; Steck, Daniel J; Field, R William

    2014-05-01

    The primary objective of this study was to investigate the temporal variability between basement winter short-term (7 to 10 d) and basement annual radon measurements. Other objectives were to test the short-term measurement's diagnostic performance at two reference levels and to evaluate its ability to predict annual average basement radon concentrations. Electret ion chamber (short-term) and alpha track (annual) radon measurements were obtained by trained personnel in Iowa residences. Overall, the geometric mean of the short-term radon concentrations (199 Bq m) was slightly greater than the geometric mean of the annual radon concentrations (181 Bq m). Short-term tests correctly predicted annual radon concentrations to be above the 148 Bq m action level 88% of the time and above a 74 Bq m level 98% of the time. The short-term and annual radon concentrations were strongly correlated (r = 0.87, p < 0.0001). The foundation wall material of the basement was the only significant factor to have an impact on the absolute difference between the short-term and annual measurements. The findings from this study provide evidence of a substantially lower likelihood of obtaining a false negative result from a single short-term test in a region with high indoor radon potential when the reference level is lowered to 74 Bq m.

  3. Variations in radon concentration in groundwater of Kumaon Himalaya, India.

    PubMed

    Bourai, A A; Gusain, G S; Rautela, B S; Joshi, V; Prasad, G; Ramola, R C

    2012-11-01

    The radon content in groundwater sources depends on the radium concentration in the rock of the aquifer. Radon was measured in water in many parts of the world, mostly for the risk assessment due to consumption of drinking water. The exposure to radon through drinking water is largely by inhalation and ingestion. Airborne radon can be released during normal household activities and can pose a greater potential health risk than radon ingested with water. Transport of radon through soil and bedrock by water depends mainly on the percolation of water through the pores and along fracture planes of bedrock. In this study, the radon concentration in water from springs and hand pumps of Kumaun Himalaya, India was measured using the radon emanometry technique. Radon concentration was found to vary from 1 to 392 Bq l(-1) with a mean of 50 Bq l(-1) in groundwater in different lithotectonic units. The radon level was found to be higher in the area consisting of granite, quartz porphyry, schist, phyllites and lowest in the area having sedimentary rocks, predominantly dominated by quartzite rocks.

  4. Environmental Assessment for moving the Pacific Northwest Laboratory radon generators from Life Sciences Laboratory II, Richland North Area, to Life Sciences Laboratory I, 300 Area, and their continued use in physical and biological research

    SciTech Connect

    Nelson, I.C.

    1993-09-01

    The Pacific Northwest Laboratory (PNL) radon generators are a core resource of the overall U. S. Department of Energy`s (DOE) Radon Research Program and are administratively controlled within the ``Radon Hazards in Homes`` project. This project primarily focuses on radon exposures of animals and addresses the major biologic effects and factors influencing risks of indoor radon exposures. For example, the ``Mechanisms of Radon Injury`` and ``In vivo/In vitro Radon-Induced Cellular Damage`` projects specifically address the cytogenetic and DNA damage produced by radon exposure as part of a larger effort to understand radon carcinogenesis. Several other ongoing PNL projects, namely: ``Biological Effectiveness of Radon Alpha Particles: A Microbeam Study of Dose Rate Effects,`` ``Laser Measurements of Pb-210,`` ``Radon Transport Modeling in Soils,`` ``Oncogenes in Radiation Carcinogenesis,`` ``Mutation of DNA Targets,`` ``Dosimetry of Radon Progeny,`` and ``Aerosol Technology Development`` also use the radon exposure facilities in the conduct of their work. While most, but not all, studies in the PNL Radon Research Program are funded through DOE`s Office of Health and Environmental Research, PNL also has ongoing collaborative radon studies with investigators worldwide; many of these use the radon exposure facilities. The purpose of the proposed action is to provide for relocation of the radon generators to a DOE-owned facility and to continue to provide a controlled source of radon-222 for continued use in physical and biological research.

  5. Ambient Radon-222 Monitoring in Amargosa Valley, Nevada

    SciTech Connect

    L.H. Karr; J.J. Tappen; D. Shafer; K.J. Gray

    2008-06-05

    As part of a program to characterize and baseline selected environmental parameters in the region around the proposed repository at Yucca Mountain, Nevada, ambient radon-222 monitoring was conducted in the rural community of Amargosa Valley, the community closest to the proposed repository site. Passive integrating radon monitors and a continuous radon monitoring instrument were deployed adjacent to the Community Environmental Monitoring Program (CEMP) (http://www.cemp.dri.edu/index.html) station located in the Amargosa Valley Community Center near the library. The CEMP station provided real-time ambient gamma exposure and meteorological data used to correct the integrated radon measurements as well as verify meteorological data collected by the continuous radon monitoring instrument. Additionally, different types of environmental enclosures that housed the monitors and instrument were used to determine if particular designs influenced the ambient radon measurements.

  6. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres. Final project report

    SciTech Connect

    Hopke, P.K.

    1996-09-01

    This report completes Clarkson University`s study of the chemical and physical behavior of the {sup 218}Po atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity in the sub-10 nm size range result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and it dose to the cells in the respiratory tract are to be fully assessed. In order to pursue this general goal, two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical processes that affect the progeny`s atmospheric behavior and studies in actual indoor environments to develop a better assessment of the exposure of the occupants of that space to the size and concentration of the indoor radioactive aerosol. Thus, two sets of specific goals have been established for this project. The specific tasks of the controlled laboratory studies are (1) Determine the formation rates of {circ}OH radicals formed by the radiolysis of air following radon decay; (2) Examine the formation of particles by the radiolytic oxidation of substances like SO{sub 2}, ethylene, and H{sub 2}S to lower vapor pressure compounds and determine the role of gas phase additives such as H{sub 2}O and NH{sub 3} in determining the particle size; (3) Measure the rate of ion-induced nucleation using a thermal diffusion cloud chamber, and (4) Measure the neutralization rate of {sup 218}PoO{sub x}{sup +} in O{sub 2} at low radon concentrations.

  7. The performance of charcoal-based radon detection under time-varying radon conditions: Experimental and theoretical results

    SciTech Connect

    Sextro, R.G.; Lee, D.D.

    1988-10-01

    Radon adsorption by charcoal is a widely used technique for measuring indoor radon concentration, particularly when short-term results are desired. There are several different devices available, ranging from permeable envelopes filled with charcoal and open-face charcoal-filled canisters to devices incorporating diffusion limiting features to reduce losses of radon due to desorption. However, the integration characteristics of these samplers are not well understood, particularly under conditions of highly varying radon concentrations. A model for predicting the response of various types of charcoal based detectors to time-variant radon concentrations has been developed; the model predictions compare well with results from chamber experiments. Both the experimental and theoretical results have also been compared with integrated continuous-sampling measurements. The implications of these comparisons for use of charcoal for screening measurements is discussed. 5 refs., 4 figs., 2 tabs.

  8. EPA Assessment of Risks from Radon in Homes

    EPA Pesticide Factsheets

    This 2003 document will serve as a technical basis for EPA’s estimates of risk from radon in homes. It provides estimates of the risk per unit exposure and projects the number of fatal lung cancers occurring in the U.S. population each year due to radon.

  9. Geologic controls on radon

    SciTech Connect

    Gates, A.E.; Gundersen, L.C.S.

    1992-01-01

    This text provides a review of recent research on geological controls of [sup 222]Rn concentrations in soil gas in relation to the problem of high indoor radon concentrations in houses. The importance of the subject matter is highlighted in the preface by the observation that the US Environmental Protection Agency (EPA) estimates that 15,000 to 25,000 deaths result from radon-induced lung cancer each year in the United States. The text contains 8 Chapters: (1) Geology of radon in the United States; (2) Sensitivity of soil radon to geology and the distribution of radon and uranium in the Hylas Zone Area, Virginia; (3) Geologic and environmental implications of high soil-gas radon concentrations in The Great Valley, Jefferson and Berkeley Counties, West Virginia; (4) Soil radon distribution in glaciated areas: an example from the New Jersey Highlands; (5) Radon in the coastal plain of Texas, Alabama, and New Jersey; (6) Effects of weather and soil characteristics on temporal variations in soil-gas radon concentrations; (7) A theoretical model for the flux of radon from rock to ground water; (8) The influence of season, bedrock, overburden, and house construction on airborne levels of radon in Maine homes. The individual chapters are written by different authors in the form of self-contained research papers, each of which is followed by a comprehensive list of references.

  10. The radon indicator

    NASA Astrophysics Data System (ADS)

    Samuelsson, L.

    2005-11-01

    The radon indicator is an efficient instrument for measuring the radon daughter concentrations in a house or dwelling. Physics or environmental science students could build a radon indicator as a student project. Another possibility would be to use a radon indicator in a student investigation of radon levels in different houses. Finally the radon indicator is an excellent device for producing a radioactive source, free of charge, for the study of α-, β- and γ-radiation. The half-life of the activity collected is approximately 40 min. The radon indicator makes use of an electrostatic method by which charged particles are drawn to a small aluminium plate with a high negative voltage (-5 kV), thus creating a strong electric field between the plate and a surrounding copper wire. The radioactivity on the plate is subsequently measured by a GM-counter and the result calculated in Bq m-3. The collecting time is just 5.5 min and therefore the instrument is only suitable for use in a short-time method for indicating the radon concentration. An improved diagram, ground-radon and/or wall-radon in houses, is presented on the basis of the author's measurements recorded with the radon indicator over many years. This diagram is very useful when discussing how to reduce radiation levels in homes.

  11. Radon is out

    SciTech Connect

    Harley, J.H.

    1992-12-31

    This paper discusses some facets of outdoor radon. There is only one source of radon - the decay of radium. Radium is everywhere but the bulk is in soil, rock, and ocean sediments. Soil porosity is a prime factor in radon movement. Exhalation from soil is fed by the high concentrations of radon in soil gas. Because the surface soil is losing radon to the atmosphere, soil gas concentration would be expected to increase with depth. There is a wide range of air radon concentrations, with marked seasonal and diurnal variations. Atmospheric stability is certainly a major factor - radon increases during inversions and decreases when the inversion breaks up. In addition, temperature, soil moisture, snow cover, and wind direction all play a part. Different investigators sometimes come to contrary conclusions on the effects of these factors. They are probably all correct - for the conditions in effect at the time - since no simple generalities exist for most factors.

  12. The impact of serial radon and hyperthermia exposure in a therapeutic adit on pivotal cytokines of bone metabolism in rheumatoid arthritis and osteoarthritis.

    PubMed

    Lange, Uwe; Dischereit, Gabriel; Tarner, Ingo; Frommer, Klaus; Neumann, Elena; Müller-Ladner, Ulf; Kürten, Bernhard

    2016-11-01

    Secondary osteoporosis is a frequent complication of rheumatoid arthritis (RA) and the result of an imbalance of catabolic and anabolic mechanisms of bone metabolism. The effects of serial low-dose radon and hyperthermia (LDRnHT) exposure in a therapeutic adit (12 applications in 3 weeks) on the serum levels of the cytokines osteoprotegerin (OPG), receptor activator of NF kappa-B ligand (RANKL), tumor necrosis factor-α (TNF-α), and also on the RANKL/OPG ratio were investigated in 25 RA patients and an age-matched control of 24 patients with osteoarthritis (OA). Cytokine measurements were performed at baseline and after completion of LDRnHT. Anti-CCP antibodies (ACPA) were measured in RA patients in parallel. Medication in both groups was limited to non-steroidal anti-inflammatory drugs, and low-dose prednisolone (16 of 24 RA patients) as needed. RA and OA patients showed a significant decrease of TNF-α levels (p < 0.001). Both groups showed significantly decreased levels of RANKL (RA: p < 0.001, OA: p < 0.01). Only the RA patients presented a significant increase of OPG (p < 0.01) and decrease of the RANKL/OPG ratio (p < 0.01), and the ACPA levels (p < 0.001). LDRnHT results in a reduction of osteocatabolic and an increase of osteoanabolic cytokines, which represents the molecular basis for inhibiting osteoclastic activity in secondary osteoporosis and explains in part the effect of LDRnHT this physical therapy modality in a key inflammatory disease. Although reduced ACPA levels were observed under the therapy and although this could potentially contribute to an osteoprotective effect, in this case, it is rather uncertain as the reduction was only minor in magnitude.

  13. Indoor concentration of radon, thoron and their progeny around granite regions in the state of Karnataka, India.

    PubMed

    Sannappa, J; Ningappa, C

    2014-03-01

    An extensive studies on the indoor activity concentrations of thoron, radon and their progeny in the granite region in the state of Karnataka, India, has been carried out since, 2007 in the scope of a lung cancer epidemiological study using solid-state nuclear track detector-based double-chamber dosemeters (LR-115, type II plastic track detector). Seventy-four dwellings of different types were selected for the measurement. The dosemeters containing SSNTD detectors were fixed 2 m above the floor. After an exposure time of 3 months (90 d), films were etched to reveal tracks. From the track density, the concentrations of radon and thoron were evaluated. The value of the indoor concentration of thoron and radon in the study area varies from 16 to 170 Bq m(-3) and 18 to 300 Bq m(-3) with medians of 66 and 82.3 Bq m(-3), respectively, and that of their progeny varies from 1.8 to 24 mWL with a median of 3.6 mWL and 1.6 to 19.6 mWL, respectively. The concentrations of indoor thoron, radon and their progeny and their equivalent effective doses are discussed.

  14. Survey of radon and thoron in homes of Indian Himalaya.

    PubMed

    Ramola, Rakesh Chand

    2011-07-01

    Measurements of radon, thoron and their progeny were carried out in some houses from Garhwal and Kumaun Himalayas of India using a LR-115 plastic track detector. The measurements were made in various residential houses of the area at a height of 2.5 m above the ground level using a twin chamber radon dosemeter, which can record the values of radon, thoron and their progeny separately. The concentrations of radon and thoron in these homes were found to vary from 11 to 191 and 1 to 156 Bq m(-3), respectively. The equilibrium factor between radon and progeny varies from 0.02 to 0.90, with an average of 0.26 for the region. The resulting dose rate due to radon, thoron and their decay products was found to vary from 0.02 to 0.84 μSv h(-1) with an arithmetic mean of 0.27 μSv h(-1). A detailed analysis of the distribution of radon, thoron and their decay products inside a house is also reported. The observed dose rates due to radon, thoron and progeny were found somewhat higher but well below the international recommendations.

  15. Atmosphere purification of radon and radon daughter elements

    DOEpatents

    Stein, L.

    1974-01-01

    A method of removing radon and radon daughter elements from an atmosphere containing these elements by passing the atmosphere through a bed of fluorinating compound whereby the radon and radon daughters are oxidized to their respective fluorides is discussed. These fluorides adhere to the fluorinating compound and are thus removed from the atmosphere which may then be recirculated. A method for recovering radon and separating radon from its daughter elements is also described. (Official Gazette)

  16. Overview of current radon and radon daughter research at LBL

    SciTech Connect

    Not Available

    1983-01-01

    This report provides a brief summary of radon and radon daughter research at Lawrence Berkeley Laboratory. The radon and radon daughter research program has two broad goals: (1) the study of sources of radon and its subsequent transport into houses, and (2) research on the behavior of radon daughters in indoor environments. Additional research effort is directed to several auxiliary areas, including development of instrumentation and monitoring techniques, studies of indoor air movement, and measurement and control of indoor particulate concentrations.

  17. Activity measurements of radon from construction materials.

    PubMed

    Fior, L; Nicolosi Corrêa, J; Paschuk, S A; Denyak, V V; Schelin, H R; Soreanu Pecequilo, B R; Kappke, J

    2012-07-01

    This work presents the results of radon concentration measurements of construction materials used in the Brazilian industry, such as clay (red) bricks and concrete blocks. The measurements focused on the detection of indoor radon activity during different construction stages and the analysis of radionuclides present in the construction materials. For this purpose, sealed chambers with internal dimensions of approximately 60×60×60 cm3 were built within a protected and isolated laboratory environment, and stable air humidity and temperature levels were maintained. These chambers were also used for radon emanation reduction tests. The chambers were built in four major stages: (1) assembly of the walls using clay (red) bricks, concrete blocks, and mortar; (2) installation of plaster; (3) finishing of wall surface using lime; and (4) insulation of wall surface and finishing using paint. Radon measurements were performed using polycarbonate etched track detectors. By comparing the three layers applied to the masonry walls, it was concluded that only the last step (wall painting using acrylic varnish) reduced the radon emanation, by a factor of approximately 2. Samples of the construction materials (clay bricks and concrete blocks) were ground, homogenized, and subjected to gamma-ray spectrometry analysis to evaluate the activity concentrations of 226Ra, 232Th and 40K. The values for the index of the activity concentration (I), radium equivalent activity (Raeq), and external hazard index (Hext) showed that these construction materials could be used without restrictions or concern about the equivalent dose limit (1 mSv/year). Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. EML pulse ionization chamber systems for /sup 222/Rn measurements

    SciTech Connect

    Fisenne, I M; Keller, H W

    1985-03-01

    Radon measurements have been performed with pulse ionization chambers at the Environmental Measurements Laboratory (EML) for over 35 years. This report describes the evolution of radon measurement systems, with emphasis on the continuous quality control efforts at EML. 38 refs., 3 figs., 3 tabs.

  19. Radon entry control in new house construction.

    PubMed

    Najafi, F T; Lalwani, L; Li, W G

    1995-07-01

    People exposed to high concentration levels of radon face an increased risk of developing lung cancer. The risk is directly proportional to the length and level of radon exposure. Because of health reasons, it is safer to build new houses with radon mitigation systems installed in slab-on-grade houses. However, the interrelationships between parameters and factors governing radon entry and control are highly complex. A study performed by the University of Florida has examined the effectiveness of different radon entry control approaches. The analysis was based on 47 houses from three research projects conducted by the University of Florida (14 houses), Florida Solar Energy Center (13 houses), and GEOMET Technologies (20 houses). The evaluation of the performance and effectiveness of improved floor slabs, space conditioning, and ventilating systems were analyzed. Statistical analyses of the interrelationship between various parameters were also performed. Study findings such as the important factors in reducing radon entry and the effectiveness of passive construction approach and active subslab depressurization systems are presented in this paper.

  20. Radon levels in underground workplaces: a map of the Italian regions.

    PubMed

    Rossetti, Marta; Esposito, Massimo

    2015-04-01

    The indoor radon exposition is a widely recognised health hazard, so specific laws and regulations have been produced in many countries and so-called radon-risk maps have consequently been produced. In Italy the regulation applies to general workplaces and a national survey was carried out in the 1990s to evaluate the exposure to radon in dwellings. Failing a national coordinated mapping programme, some Italian regions performed a survey to identify radon-prone areas, nevertheless with different methodologies. In this work a national map of the average annual radon concentration levels in underground workplaces, obtained from the results of 8695 annual indoor radon measurements carried out by U-Series laboratory between 2003 and 2010, was presented. Due to underground locations, the mean radon concentration is higher than that from previous map elaborated for dwellings and a significant radon concentration was also found in Regions traditionally considered as low-risk areas.

  1. Carcinogenesis and low-level ionizing radiation with special reference to lung cancer and exposure to radon daughters

    SciTech Connect

    Fabrikant, J.I.

    1982-04-01

    Of the important health effects of ionizing radiation, three important late effects - carcinogenesis, teratogenesis and mutagenesis are of greatest concern. This is because any exposure, even at low levels, carries some risk of such deleterious effects. As the dose of radiation increases above very low levels, the risk of health effects increases. Cancer-induction is the most important late somatic effect of low-dose ionizing radiation. Solid cancers, rather than leukemia, are principal late effects in exposed individuals. Tissues vary greatly in their susceptibility to radiation carcinogenesis. The most frequently occurring radiation-induced cancers in man include, in decreasing order of susceptibility: the female breast, the thyroid gland, the blood-forming tissues, the lung, certain organs of the gastrointestinal tract, and the bones. A number of biological and physical factors affect the cancer risk, such as age, sex, life-style, LET, and RBE. Despite uncertainty about low-level radiation risks, regulatory and advisory bodies must set standards for exposure, and individuals need information to be able to make informed judgments for themselves. From the point of view of the policy maker, the overriding concern is the fact that small doses of radiation can cause people to have more cancers than would otherwise be expected. While concern for all radiation effects exists, our human experience is limited to cancer-induction in exposed populations. This discussion is limited to cancer risk estimation and decision-making in relation to the health effects on populations of exposure to low levels of ionizing radiation. Here, low-level radiation will refer to yearly whole-body doses up to 5 rems or 0.05 Sv, or to cumulative doses up to 50 rems or 0.5 Sv from low-LET radiation and from high-LET radiation. (ERB)

  2. Preliminary results regarding the first map of residential radon in some regions in Romania.

    PubMed

    Cosma, C; Cucoş Dinu, A; Dicu, T

    2013-07-01

    Radon represents the most important contribution of population exposure to natural ionising radiation. This article presents the first indoor radon map in some regions of Romania based on 883 surveyed buildings in the Ştei-BăiŢa radon-prone region and 864 in other regions of Romania. Indoor radon measurements were performed in the last 10 y by using CR-39 nuclear track detectors exposed for 3-12 months on ground floor levels of dwellings. Excluding the Ştei-BăiŢa radon-prone region, an average indoor radon concentration of 126 Bq m(-3) was calculated for Romanian houses. In the Ştei-BăiŢa radon-prone area, the average indoor concentration was 292 Bq m(-3). About 21 % of the investigated dwellings in the Ştei-BăiŢa radon-prone region exceed the threshold of 400 Bq m(-3), while 5 % of the dwellings in other areas of Romania exceed the same threshold. As expected, indoor radon concentration is not uniformly distributed throughout Romania. The map shows a high variability among surveyed regions, mainly due to the differences in geology. The radon emanation rate is substantially influenced by the soil characteristics, such as the soil permeability and soil gas radon concentration. Since higher permeability enables the increased migration of soil gas and radon from the soil into the building, elevated levels of indoor radon can be expected in more permeable soil environments.

  3. Radon assay and purification techniques

    SciTech Connect

    Simgen, Hardy

    2013-08-08

    Radon is a source of background in many astroparticle physics experiments searching for rare low energy events. In this paper an overview about radon in the field is given including radon detection techniques, radon sources and material screening with respect to radon emanation. Finally, also the problem of long-lived radioactive {sup 222}Rn-daughters and the question of gas purification from radon is addressed.

  4. The performance of functional methods for correcting non-Gaussian measurement error within Poisson regression: corrected excess risk of lung cancer mortality in relation to radon exposure among French uranium miners.

    PubMed

    Allodji, Rodrigue S; Thiébaut, Anne C M; Leuraud, Klervi; Rage, Estelle; Henry, Stéphane; Laurier, Dominique; Bénichou, Jacques

    2012-12-30

    A broad variety of methods for measurement error (ME) correction have been developed, but these methods have rarely been applied possibly because their ability to correct ME is poorly understood. We carried out a simulation study to assess the performance of three error-correction methods: two variants of regression calibration (the substitution method and the estimation calibration method) and the simulation extrapolation (SIMEX) method. Features of the simulated cohorts were borrowed from the French Uranium Miners' Cohort in which exposure to radon had been documented from 1946 to 1999. In the absence of ME correction, we observed a severe attenuation of the true effect of radon exposure, with a negative relative bias of the order of 60% on the excess relative risk of lung cancer death. In the main scenario considered, that is, when ME characteristics previously determined as most plausible from the French Uranium Miners' Cohort were used both to generate exposure data and to correct for ME at the analysis stage, all three error-correction methods showed a noticeable but partial reduction of the attenuation bias, with a slight advantage for the SIMEX method. However, the performance of the three correction methods highly depended on the accurate determination of the characteristics of ME. In particular, we encountered severe overestimation in some scenarios with the SIMEX method, and we observed lack of correction with the three methods in some other scenarios. For illustration, we also applied and compared the proposed methods on the real data set from the French Uranium Miners' Cohort study.

  5. Establishment of Airborne Nanoparticle Exposure Chamber System to Assess Nano TiO2 Induced Mice Lung Effects

    NASA Astrophysics Data System (ADS)

    Chen, Chia-Hua; Li, Jui-Ping; Huang, Nai-Chun; Yang, Chung-Shi; Chen, Jen-Kun

    2011-12-01

    A great many governments have schemed their top priority to support the research and development of emerging nanotechnology, which lead to increasing products containing nanomaterials. However, platforms and protocols to evaluate the safety of nanomaterials are not yet established. We therefore design and fabricate a nanoparticle exposure chamber system (NECS) and try to standardize protocols to assess potential health risk of inhalable nanoparticles. This platform comprises: (1) nano-aerosol generators to produce homogeneous airborne nanoparticles, (2) double isolated container to prevent from unexpected exposure to humans, (3) gas supply system for housing animals or incubating cultured cells, and (4) system for automatic control and airborne nanoparticle analysis. The NECS providing multiple functions includes: (1) a secure environment to handle nanomaterials, (2) real-time measurement for the size and distribution of airborne nanoparticles, (3) SOP of safety evaluation for nanomaterials, and (4) key technology for the development of inhalable pharmaceuticals. We used NECS to mimic occupational environment for exploring potential adverse effects of TiO2 nanoparticles. The adult male ICR mice were exposed to 25nm, well-characterized TiO2 particles for 1 and 4 weeks. More than 90% of the inhaled TiO2 nanoparticles deposit in lung tissue, which tends to be captured by alveolar macrophages. Pulmonary function test does not show significant physiological changes between one and 4 weeks exposure. For plasma biochemistry analysis, there are no obvious inflammation responses after exposure for one and 4 weeks; however, disruption of alveolar septa and increased thickness of alveolar epithelial cells were observed. According to our results, the NECS together with our protocols show comprehensive integration and ideally fit the standard of OECD guildelines-TG403, TG412, TG413; it can be further customized to fulfill diverse demands of industry, government, and third party

  6. Radon exhalation from building materials for decorative use.

    PubMed

    Chen, Jing; Rahman, Naureen M; Abu Atiya, Ibrahim

    2010-04-01

    Long-term exposure to radon increases the risk of developing lung cancer. There is considerable public concern about radon exhalation from building materials and the contribution to indoor radon levels. To address this concern, radon exhalation rates were determined for 53 different samples of drywall, tile and granite available on the Canadian market for interior home decoration. The radon exhalation rates ranged from non-detectable to 312 Bq m(-2) d(-1). Slate tiles and granite slabs had relatively higher radon exhalation rates than other decorative materials, such as ceramic or porcelain tiles. The average radon exhalation rates were 30 Bq m(-2) d(-1) for slate tiles and 42 Bq m(-2) d(-1) for granite slabs of various types and origins. Analysis showed that even if an entire floor was covered with a material having a radon exhalation rate of 300 Bq m(-2) d(-1), it would contribute only 18 Bq m(-3) to a tightly sealed house with an air exchange rate of 0.3 per hour. Generally speaking, building materials used in home decoration make no significant contribution to indoor radon for a house with adequate air exchange.

  7. A theoretical investigation of the distribution of indoor radon concentrations

    NASA Astrophysics Data System (ADS)

    Rabi, R.; Oufni, L.

    2017-05-01

    Inhalation of radon (222Rn) and its decay products are a major source of natural radiation exposure. It is known from recent surveys in many countries that radon and its progeny contribute significantly to total inhalation dose and it is fairly established that radon when inhaled in large quantity causes lung disorder. In recent times, numerical modelling has become the cost effective replacement of experimental methods for the prediction and visualization of indoor pollutant distribution. The aim of this study is to implement the Finite Volume Method (FVM) for studying the radon distribution indoor. The findings show that the radon concentration which is distributed in a non-homogeneous way in the room is due to the difference in the radon concentration of different sources (wall, floor and ceiling). Moreover, the radon concentration is much larger near walls, and decreases in the middle of the room because of the effect of air velocity. We notice that the simulation results of radon concentration are in agreement with the results of other experimental studies. The annual effective dose of radon in the model room has been also investigated.

  8. A theoretical investigation of the distribution of indoor radon concentrations

    NASA Astrophysics Data System (ADS)

    Rabi, R.; Oufni, L.

    2016-11-01

    Inhalation of radon (222Rn) and its decay products are a major source of natural radiation exposure. It is known from recent surveys in many countries that radon and its progeny contribute significantly to total inhalation dose and it is fairly established that radon when inhaled in large quantity causes lung disorder. In recent times, numerical modelling has become the cost effective replacement of experimental methods for the prediction and visualization of indoor pollutant distribution. The aim of this study is to implement the Finite Volume Method (FVM) for studying the radon distribution indoor. The findings show that the radon concentration which is distributed in a non-homogeneous way in the room is due to the difference in the radon concentration of different sources (wall, floor and ceiling). Moreover, the radon concentration is much larger near walls, and decreases in the middle of the room because of the effect of air velocity. We notice that the simulation results of radon concentration are in agreement with the results of other experimental studies. The annual effective dose of radon in the model room has been also investigated.

  9. Mineral dusts and radon in uranium mines

    SciTech Connect

    Abelson, P.H.

    1991-11-08

    The Environmental Protection Agency (EPA) continues to assert that radon is a major cause of lung cancer in this country. EPA is fostering a radon program that could entail huge financial and emotional costs while yielding negligible benefits to public health. Justification for the program was the occurrence of lung cancer in men exposed to huge amounts of radon, mineral dusts, and other lung irritants in uranium mines on the Colorado Plateau. Lung cancer has been reported in about 356 cigarette smokers and in about 25 nonsmokers. During the era of high radon levels, monitoring was sporadic. Conditions in only a small fraction of the mines were measured, and that on a few separate occasions. Later, cumulative exposure to radon was calculated on the basis of measurements involving only a tiny fraction of the miners. Some were exposed to more than 15,000 pCi/liter of radon and its products. The level in the average home is about 1.5 pCi/liter. In making extrapolations from mine to home, the assumption is made that residents are in their dwellings most of the time and that miners spend only 170 hours a month in the mine. Two major questionable assumptions are involved in extrapolations from high doses of radon in the mines to low doses in homes. One is that no threshold is involved; that is, that humans have no remediation mechanism for {alpha} particle damages. There is evidence to the contrary. The most unrealistic assumption is that heavy exposure to silica has no effect on inducing lung cancer. Many studies have shown that silica dust causes lung cancer in animals. Exposure of human culture cells to silica has resulted in formation of neoplastic tissue. EPA has no solid evidence that exposures to 4 pCi/liter of radon causes lung cancer in either smokers or nonsmokers. Indeed, there is abundant evidence to the contrary in the fact that in states with high levels of radon, inhabitants have less lung cancer than those in states with low levels.

  10. The measurement accuracy of passive radon instruments.

    PubMed

    Beck, T R; Foerster, E; Buchröder, H; Schmidt, V; Döring, J

    2014-01-01

    This paper analyses the data having been gathered from interlaboratory comparisons of passive radon instruments over 10 y with respect to the measurement accuracy. The measurement accuracy is discussed in terms of the systematic and the random measurement error. The analysis shows that the systematic measurement error of the most instruments issued by professional laboratory services can be within a range of ±10 % from the true value. A single radon measurement has an additional random measurement error, which is in the range of up to ±15 % for high exposures to radon (>2000 kBq h m(-3)). The random measurement error increases for lower exposures. The analysis especially applies to instruments with solid-state nuclear track detectors and results in proposing criteria for testing the measurement accuracy. Instruments with electrets and charcoal have also been considered, but the low stock of data enables only a qualitative discussion.

  11. Residential Radon and Brain Tumour Incidence in a Danish Cohort

    PubMed Central

    Bräuner, Elvira V.; Andersen, Zorana J.; Andersen, Claus E.; Pedersen, Camilla; Gravesen, Peter; Ulbak, Kaare; Hertel, Ole; Loft, Steffen; Raaschou-Nielsen, Ole

    2013-01-01

    Background Increased brain tumour incidence over recent decades may reflect improved diagnostic methods and clinical practice, but remain unexplained. Although estimated doses are low a relationship between radon and brain tumours may exist. Objective To investigate the long-term effect of exposure to residential radon on the risk of primary brain tumour in a prospective Danish cohort. Methods During 1993–1997 we recruited 57,053 persons. We followed each cohort member for cancer occurrence from enrolment until 31 December 2009, identifying 121 primary brain tumour cases. We traced residential addresses from 1 January 1971 until 31 December 2009 and calculated radon concentrations at each address using information from central databases regarding geology and house construction. Cox proportional hazards models were used to estimate incidence rate-ratios (IRR) and 95% confidence intervals (CI) for the risk of primary brain tumours associated with residential radon exposure with adjustment for age, sex, occupation, fruit and vegetable consumption and traffic-related air pollution. Effect modification by air pollution was assessed. Results Median estimated radon was 40.5 Bq/m3. The adjusted IRR for primary brain tumour associated with each 100 Bq/m3 increment in average residential radon levels was 1.96 (95% CI: 1.07; 3.58) and this was exposure-dependently higher over the four radon exposure quartiles. This association was not modified by air pollution. Conclusions We found significant associations and exposure-response patterns between long-term residential radon exposure radon in a general population and risk of primary brain tumours, adding new knowledge to this field. This finding could be chance and needs to be challenged in future studies. PMID:24066143

  12. Results of simultaneous radon and thoron measurements in 33 metropolitan areas of Canada

    PubMed Central

    Chen, Jing; Bergman, Lauren; Falcomer, Renato; Whyte, Jeff

    2015-01-01

    Radon has been identified as the second leading cause of lung cancer after tobacco smoking. 222Rn (radon gas) and 220Rn (thoron gas) are the most common isotopes of radon. In order to assess thoron contribution to indoor radon and thoron exposure, a survey of residential radon and thoron concentrations was initiated in 2012 with ∼4000 homes in the 33 census metropolitan areas of Canada. The survey confirmed that indoor radon and thoron concentrations are not correlated and that thoron concentrations cannot be predicted from widely available radon information. The results showed that thoron contribution to the radiation dose varied from 0.5 to 6 % geographically. The study indicated that, on average, thoron contributes ∼3 % of the radiation dose due to indoor radon and thoron exposure in Canada. Even though the estimated average thoron concentration of 9 Bq m−3 (population weighted) in Canada is low, the average radon concentration of 96 Bq m−3 (population weighted) is more than double the worldwide average indoor radon concentration. It is clear that continued efforts are needed to further reduce the exposure and effectively reduce the number of lung cancers caused by radon. PMID:24748485

  13. Results of simultaneous radon and thoron measurements in 33 metropolitan areas of Canada.

    PubMed

    Chen, Jing; Bergman, Lauren; Falcomer, Renato; Whyte, Jeff

    2015-02-01

    Radon has been identified as the second leading cause of lung cancer after tobacco smoking. (222)Rn (radon gas) and (220)Rn (thoron gas) are the most common isotopes of radon. In order to assess thoron contribution to indoor radon and thoron exposure, a survey of residential radon and thoron concentrations was initiated in 2012 with ∼4000 homes in the 33 census metropolitan areas of Canada. The survey confirmed that indoor radon and thoron concentrations are not correlated and that thoron concentrations cannot be predicted from widely available radon information. The results showed that thoron contribution to the radiation dose varied from 0.5 to 6% geographically. The study indicated that, on average, thoron contributes ∼3% of the radiation dose due to indoor radon and thoron exposure in Canada. Even though the estimated average thoron concentration of 9 Bq m(-3) (population weighted) in Canada is low, the average radon concentration of 96 Bq m(-3) (population weighted) is more than double the worldwide average indoor radon concentration. It is clear that continued efforts are needed to further reduce the exposure and effectively reduce the number of lung cancers caused by radon.

  14. The National Radon Action Plan - A Strategy for Saving Lives

    EPA Pesticide Factsheets

    NRAP Guide-A Strategy for Saving Lives sets out strategies to drive the changes needed to reduce exposure to radon, a naturally occurring, invisible and odorless gas. Partnership headed by ALA with feds and NGOs.

  15. Portable apparatus for the measurement of environmental radon and thoron

    DOEpatents

    Negro, Vincent C.

    2001-01-01

    The radometer is a portable instrument for the measurement of the concentration of atmospheric radon/thoron in a test area. A constant velocity pump pulls the air from the outside at a constant flow rate. If the air is too moist, some or all of the sample is passed through a desiccant filter prior to encountering an electrostatic filter. The electrostatic filter prevents any charged particles from entering the sampling chamber. Once the sample has entered the chamber, the progeny of the decay of radon/thoron are collected on a detector and measured. The measured data is compiled by a computer and displayed.

  16. The Spanish indoor radon mapping strategy.

    PubMed

    Sainz-Fernandez, C; Fernandez-Villar, A; Fuente-Merino, I; Gutierrez-Villanueva, J L; Martin-Matarranz, J L; Garcia-Talavera, M; Casal-Ordas, S; Quindós-Poncela, L S

    2014-11-01

    Indoor radon mapping still represents a valuable tool for drawing the picture of the exposure of general public due to radon and radon progeny inhalation in a residential context. The information provided by means of a map is useful not only as awareness and strategic element for authorities and policy-makers, but also as a scientific start-up point in the design of epidemiological and other specific studies on exposure to natural radiation. The requirements for a good mapping are related to harmonisation criteria coming from European recommendations, as well as to national/local characteristics and necessities. Around 12,000 indoor radon measurements have been made since the Spanish national radon programme began at the end of the 1980s. A significant proportion of them resulted from the last campaign performed from 2009 to 12. This campaign completed the first version of a map based on a grid 10 × 10 km(2). In this paper, the authors present the main results of a new map together with the criteria adopted to improve the number of measurements and the statistical significance of them.

  17. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres. Progress report, July 1, 1992--March 31, 1993

    SciTech Connect

    Hopke, P.K.

    1992-07-01

    This report describes studies on the chemical and physical behavior of the {sup 218}Po atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity in the sub-10 nm size range result in large changes in the delivered dose per unit exposure, this behavior must be understood if the exposure to radon progeny and its dose to the cells in the respiratory tract are to be fully assessed. The specific tasks of the controlled laboratory studies are to determine the formation rates of {center_dot}OH radicals formed by the radiolysis of air following radon decay, to examine the formation of particles by the radiolytic oxidation of substances like SO{sub 2} ethylene, and H{sub 2}S to lower vapor pressure compounds and determine the role of gas phase additives such as H{sub 2}O and NH{sub 3} in determining the particle size, to measure the rate of ion-induced nucleation using a thermal diffusion cloud chamber, and to measure the neutralization rate of {sup 218}Po{sub x}{sup +} in O{sub 2} at low radon concentrations. Tasks of the exposure studies in occupied indoor spaces are to initiate measurements of the activity size distributions in actual homes with occupants present so that the variability of the indoor activity size distributions can be assessed with respect to indoor aerosol sources and general lifestyle variations of the occupants, to initiate a prospective study of the utility of measurement of deposited {sup 210}Pb embedded in glass surfaces as a measure of the long-term, integrated exposure of the population to radon, and to develop the methodology to determine the hygroscopicity of the indoor aerosol so that the changes in deposition efficiency of the radioactive indoor aerosol with hygroscopic growth in the respiratory tract can be assessed.

  18. The radon inverse dose rate effect and high-LET galactic hazards.

    PubMed

    Leonard, Bobby E

    2005-01-01

    The lung dose rate per unit 222Rn concentration in enclosed spaces is shown to experience transitions at high radon concentrations. This has implications on the radon inverse dose rate effect. At an air change rate (ACH) of 0.194 h(-1) and relative humidity (RH) of 52.3% in a 0.283 m3 test chamber, the total human lung dose for an adult male in a residential setting (breathing rate 0.78 m3 h(-1)) would undergo a reduction of 2.5 using the ICRP 66 human respiratory tract model and the BEIR VI methodology. Using the same methodology of both Cross (Pacific Northwest Laboratory rat exposures) and Lubin et al. (miners dose rates), adjustments are necessary for effects of RH and ACHs. These adjustments, however, do not affect the reduction behaviour. It is thus shown that the enhanced deposition effect (EDE) must influence the magnitude of the purported inverse dose rate effect (IDRE). In the analysis of animal data, Cross rat exposures in a 2.0 m3 chamber, a reduction in lung dose is estimated to be over a factor of 3 the transition between the 50 and 500 WLM week(-1) dose rate range. For an estimation of the EDE, using a hypothetical 30 m3 enclosure for underground miners, we obtain a factor of approximately 4 in human lung dose reduction. Although the extensive analyses required make these results qualitative, the EDE behaviour is sufficiently conclusive that these estimates show that the radon IDRE for lung cancer must be an EDE dosimetric issue as well as a radiological lung cell dose response issue. The consequence of analysis of other animal data would achieve the same conclusion.

  19. Development and use of a branch exposure chamber to determine the effects of ozone on Pinus ponderosa: Objectives and experimental design

    SciTech Connect

    Houpis, J.L.J.; Surano, K.A.; Cowles, S.

    1988-01-01

    This research will develop a branch exposure chamber (BEC) to determine if the amount of carbon a branch receives from neighboring branches is altered by the presence of a BEC, or is altered by the imposition or exclusion of O/sub 3/, and to examine if the response of mature branches is different.

  20. Potential for bias in epidemiologic studies that rely on glass-based retrospective assessment of radon

    SciTech Connect

    Weinberg, C.R.

    1995-11-01

    Retrospective assessment of exposure to radon remains the greatest challenge in epidemiologic efforts to assess lung cancer risk associated with residential exposure. An innovative technique based on measurement of {alpha}-emitting, long-lived daughters embedded by recoil into household glass may one day provide improved radon dosimetry. Particulate air pollution is known, however, to retard the plate-out of radon daughters. This would be expected to result in a differential effect on dosimetry, where the calibration curve relating the actual historical radon exposure to the remaining {alpha}-activity in the glass would be different in historically smoky and nonsmoky environments. The resulting {open_quotes}measurement confounding{close_quotes} can distort inferences about the effect of radon and can also produce spurious evidence for synergism between radon exposure and cigarette smoking. 18 refs., 4 figs.

  1. Calibration of the Politrack® system based on CR39 solid-state nuclear track detectors for passive indoor radon concentration measurements.

    PubMed

    Kropat, G; Baechler, S; Bailat, C; Barazza, F; Bochud, F; Damet, J; Meyer, N; Palacios Gruson, M; Butterweck, G

    2015-11-01

    Swiss national requirements for measuring radon gas exposures demand a lower detection limit of 50 kBq h m(-3), representing the Swiss concentration average of 70 Bq m(-3) over a 1-month period. A solid-state nuclear track detector (SSNTD) system (Politrack, Mi.am s.r.l., Italy) has been acquired to fulfil these requirements. This work was aimed at the calibration of the Politrack system with traceability to international standards and the development of a procedure to check the stability of the system. A total of 275 SSNTDs was exposed to 11 different radon exposures in the radon chamber of the Secondary Calibration Laboratory at the Paul Scherrer Institute, Switzerland. The exposures ranged from 50 to 15000 kBq h m(-3). For each exposure of 20 detectors, 5 SSNTDs were used to monitor possible background exposures during transport and storage. The response curve and the calibration factor of the whole system were determined using a Monte Carlo fitting procedure. A device to produce CR39 samples with a reference number of tracks using a (241)Am source was developed for checking the long-term stability of the Politrack system. The characteristic limits for the detection of a possible system drift were determined following ISO Standard 11929. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Radon concentration of waters in Greece and Cyprus

    NASA Astrophysics Data System (ADS)

    Nikolopoulos, D.; Vogiannis, E.; Louizi, A.

    2009-04-01

    Radon (222Rn) is a radioactive gas generated by the decay of the naturally occurring 238U series. It is considered very important from radiological point of view, since it is the most significant natural source of human radiation exposure (approximately 50% from all natural sources). Radon is present in soil, rocks, building materials and waters. Through diffusion and convection, radon migrates and emanates to the atmosphere. Outdoors, radon concentrates at low levels (in the order of 10 Bq/m3). However indoors, radon accumulates significantly. It is trivial to observe indoor environments with high radon levels (in the order of 400 Bq/m3 or higher). Radon accumulation indoors, depends on the composition of the underlying soil and rock formation, on building materials, meteorological parameters, ventilation, heating and water use. Although soil and building materials are the most significant radon sources, there have been reported elevated radon concentrations in building structures due to entering water. It is the radon concentrations in the entering water, the volume and the way of water usage, separated or in combination, that result in large amounts of radon in indoor air. Moreover, radon is a factor of stomach radiation burden due to water consumption. This burden is estimated by measurements of radon concentrations in waters. Due to the health impact of radon exposure, the reporting team continuously measures radon. This work focused on the radon concentrations exposure due to water consumption and use in Greece and Cyprus. Various locations in Greece and Cyprus were accessed taking into consideration existing natural radioactivity data (mainly radon in water), however under the restriction of the capability of movement. Radon in water was measured by Alpha Guard (Genitron Ltd) via a special unit (Aqua Kit). This unit consists of a vessel used for forced degassing of radon diluted in water samples, a security vessel used for water drop deposition. Vessels and

  3. Mitigating factors on air concentrations of radon emanating from different granite samples

    SciTech Connect

    Qari, T.M.; Mamoon, A.M.; Abdul-Fattah, A.F. )

    1991-11-01

    Continuous exposure to increased air concentrations of radon in living areas is to be avoided according to the Environmental Protection Agency (EPA) and several published reports. Radon concentrations in ambient air are influenced by several factors related to the nature of the radon source itself, environmental conditions, and the presence of mitigating factors, if any. In this study, crushed granite samples of different types, particle diameters, and moisture contents were compared in simplified test systems with regard to radon emanation from the samples. The effects of selected mitigating factors, namely, ventilation and different barriers to diffusion of emanated radon were determined.

  4. Atmosphere purification of radon and radon daughter elements

    DOEpatents

    Stein, L.

    1973-12-11

    A method for purifying an atmosphere of radon and radon daughter elements which may be contained therein by contacting the atmosphere with a fluorinating solution, whereby the radon and radon daughters are oxidized to their respective fluorides is discussed. The fluorides dissolve in the fluorinating solutlon and are removed from the atmosphere, which may then be recirculated. (Official Gazette)

  5. RADON REDUCTION AND RADON RESISTANT CONSTRUCTION DEMONSTRATIONS IN NEW YORK

    EPA Science Inventory

    The report covers three tasks related to indoor radon: (1) the demonstration of radon reduction techniques in 8 houses in each of two uniquely different radon prone areas of the State of New York; (2) the evaluation and repair of 14 radon mitigation systems in houses mitigated 4 ...

  6. RADON REDUCTION AND RADON RESISTANT CONSTRUCTION DEMONSTRATIONS IN NEW YORK

    EPA Science Inventory

    The report covers three tasks related to indoor radon: (1) the demonstration of radon reduction techniques in 8 houses in each of two uniquely different radon prone areas of the State of New York; (2) the evaluation and repair of 14 radon mitigation systems in houses mitigated 4 ...

  7. Epidemiological implications of spatial and temporal radon variations

    SciTech Connect

    Steck, D.J.; Lively, R.S.; Ney, E.P.

    1992-12-31

    Epidemiological studies require accurate assessments of total radon-daughter exposures. Short-term radon measurements taken in current dwellings may misrepresent past exposures. In the upper midwest, we have observed significant spatial variation, on a scale of several kilometers, in yearly average indoor radon concentrations. Thus, ecological studies using small samples, or case-control studies using only the current residences for exposure assessment, could misjudge the actual long-term exposures if the size of the geographical cluster used is larger than a county. Short-term measurements also may introduce unacceptable variation. In a comparison of two measurement techniques in 80 upper-midwest homes, a correlation was found between year-long alpha-track and 2-day charcoal canister measurements. However, the observed coefficient of variation (factor of two) between measurement protocols may introduce enough scatter to obscure weak correlations in small samples. A correlation that was observed between lung-cancer rates in 13 rural Minnesota counties and the annual-average radon concentration (median = 100 Bq m{sup {minus}3}) estimated from year-long alpha-track measurements was not found when charcoal canister data were used to estimate the radon exposure. Year-to-year variations may also be important. In 12 homes that have been monitored for longer than 1 y, yearly variations ranged from 0 to 500%, with a median variation of 22%. We are investigating a retrospective detection technique that may improve long-term radon exposure assessments. We have found correlation between the surface alpha activity and radon exposure for glass surfaces exposed from 6 to 2000 kBq y m{sup {minus}3}. We have developed an alpha-track detection system that measures both current radon concentrations and exposure history.

  8. Risks from Radon: Reconciling Miner and Residential Epidemiology

    SciTech Connect

    Chambers, Douglas B.; Harley, Naomi H.

    2008-08-07

    Everyone is exposed to radon, an inert radioactive gas that occurs naturally and is present everywhere in the atmosphere. The annual dose from radon and its (short-lived) decay products is typically about one-half of the dose received by members of the public from all natural sources of ionizing radiation. Data on exposures and consequent effects have recently been reviewed by the National Council on Radiation Protection and Measurements (NCRP) and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Studies of underground miners provides a well-established basis for estimating risks from occupational exposures to radon and for studying factors that may affect the dose response relationship such as the reduction of risk (coefficients) with increasing time since exposure. Miners' studies previously formed the basis for estimating risks to people exposed to radon at home, with downward extrapolation from exposures in mines to residential levels of radon. Presently, the risk estimates from residential studies are adequate to estimate radon risks in homes. Although there are major uncertainties in extrapolating the risks of exposure to radon from the miner studies to assessing risks in the home, there is remarkably good agreement between the average of risk factors derived from miner studies and those from pooled residential case-control studies. There are now over 20 analytical studies of residential radon and lung cancer. These studies typically assess the relative risk from exposure to radon based on estimates of residential exposure over a period of 25 to 30 years prior to diagnosis of lung cancer. Recent pooled analyses of residential case-control studies support a small but detectable lung cancer risk from residential exposure, and this risk increases with increasing concentrations. The excess relative risk of lung cancer from long-term residential exposure is about the same for both smokers and non-smokers; however, because the

  9. Risks from Radon: Reconciling Miner and Residential Epidemiology

    NASA Astrophysics Data System (ADS)

    Chambers, Douglas B.; Harley, Naomi H.

    2008-08-01

    Everyone is exposed to radon, an inert radioactive gas that occurs naturally and is present everywhere in the atmosphere. The annual dose from radon and its (short-lived) decay products is typically about one-half of the dose received by members of the public from all natural sources of ionizing radiation. Data on exposures and consequent effects have recently been reviewed by the National Council on Radiation Protection and Measurements (NCRP) and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Studies of underground miners provides a well-established basis for estimating risks from occupational exposures to radon and for studying factors that may affect the dose response relationship such as the reduction of risk (coefficients) with increasing time since exposure. Miners' studies previously formed the basis for estimating risks to people exposed to radon at home, with downward extrapolation from exposures in mines to residential levels of radon. Presently, the risk estimates from residential studies are adequate to estimate radon risks in homes. Although there are major uncertainties in extrapolating the risks of exposure to radon from the miner studies to assessing risks in the home, there is remarkably good agreement between the average of risk factors derived from miner studies and those from pooled residential case-control studies. There are now over 20 analytical studies of residential radon and lung cancer. These studies typically assess the relative risk from exposure to radon based on estimates of residential exposure over a period of 25 to 30 years prior to diagnosis of lung cancer. Recent pooled analyses of residential case-control studies support a small but detectable lung cancer risk from residential exposure, and this risk increases with increasing concentrations. The excess relative risk of lung cancer from long-term residential exposure is about the same for both smokers and non-smokers; however, because the

  10. Radon gas: Health risks and toxicity. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    Not Available

    1993-08-01

    The bibliography contains citations concerning health risks and toxicity associated with indoor and outdoor exposure to radon gas. Citations discuss radon sources from tobacco smoke, fossil fuel combustion, phosphate mining, uranium mining, granitic rocks, building materials, and water supplies. Discussed also are risk assessment, regulations, radon gas monitoring, exposure modeling and control, biological pathways, and occupational exposure. Radionuclides in groundwater, and radon analysis and detection, are examined in separate bibliographies. (Contains a minimum of 125 citations and includes a subject term index and title list.)

  11. An historical overview of radon and its progeny: applications and health effects.

    PubMed

    Mc Laughlin, J

    2012-11-01

    Since its discovery by Dorn in 1900, studies of radon and its progeny have contributed to such diverse scientific fields as meteorology, geophysics, mineral exploration and radiation health effects. In addition to terrestrial scientific studies of radon, NASA missions in recent decades have yielded data on the behaviour of radon and its progeny on the Moon and on Mars. Radon has been used therapeutically for ∼100 y in the form of radon seeds for the irradiation of malignant tumours. It is, however, for its negative health effects that radon is better and more justifiably known. The causal role of radon and, in particular, its progeny in the elevated incidence of lung cancer in underground uranium miners was established in the 1950s. It is of historical interest to note that the fatal lung disease of silver miners in Saxony and Bohemia in the 16th century, was undoubtedly lung cancer caused by the high levels of radon in the mines. In recent decades there has been an ever-growing interest in the public health effects of exposure to radon in homes. Extensive radon epidemiological studies both of underground miners and of the general public in recent decades have quantified the lung cancer risks from radon exposure. Radon was classified in 1988 by International Agency for Research on Cancer as a human carcinogen and in 2009 the World Health Organization identified radon as the second cause of lung cancer globally after smoking. Radon control strategies are used by many governments to control and reduce the risk to public health from radon.

  12. Human Lung Cancer Risks from Radon – Part III - Evidence of Influence of Combined Bystander and Adaptive Response Effects on Radon Case-Control Studies - A Microdose Analysis

    PubMed Central

    Leonard, Bobby E.; Thompson, Richard E.; Beecher, Georgia C.

    2012-01-01

    Since the publication of the BEIR VI (1999) report on health risks from radon, a significant amount of new data has been published showing various mechanisms that may affect the ultimate assessment of radon as a carcinogen, in particular the potentially deleterious Bystander Effect (BE) and the potentially beneficial Adaptive Response radio-protection (AR). The case-control radon lung cancer risk data of the pooled 13 European countries radon study (Darby et al 2005, 2006) and the 8 North American pooled study (Krewski et al 2005, 2006) have been evaluated. The large variation in the odds ratios of lung cancer from radon risk is reconciled, based on the large variation in geological and ecological conditions and variation in the degree of adaptive response radio-protection against the bystander effect induced lung damage. The analysis clearly shows Bystander Effect radon lung cancer induction and Adaptive Response reduction in lung cancer in some geographical regions. It is estimated that for radon levels up to about 400 Bq m−3 there is about a 30% probability that no human lung cancer risk from radon will be experienced and a 20% probability that the risk is below the zero-radon, endogenic spontaneous or perhaps even genetically inheritable lung cancer risk rate. The BEIR VI (1999) and EPA (2003) estimates of human lung cancer deaths from radon are most likely significantly excessive. The assumption of linearity of risk, by the Linear No-Threshold Model, with increasing radon exposure is invalid. PMID:22942874

  13. LARGE BUILDING RADON MANUAL

    EPA Science Inventory

    The report summarizes information on how bilding systems -- especially the heating, ventilating, and air-conditioning (HVAC) system -- inclurence radon entry into large buildings and can be used to mitigate radon problems. It addresses the fundamentals of large building HVAC syst...

  14. LARGE BUILDING RADON MANUAL

    EPA Science Inventory

    The report summarizes information on how bilding systems -- especially the heating, ventilating, and air-conditioning (HVAC) system -- inclurence radon entry into large buildings and can be used to mitigate radon problems. It addresses the fundamentals of large building HVAC syst...

  15. Variance of indoor radon concentration: Major influencing factors.

    PubMed

    Yarmoshenko, I; Vasilyev, A; Malinovsky, G; Bossew, P; Žunić, Z S; Onischenko, A; Zhukovsky, M

    2016-01-15

    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 Niška 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 Niška 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. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. The reliability of radon as seismic precursor

    NASA Astrophysics Data System (ADS)

    Emilian Toader, Victorin; Moldovan, Iren Adelina; Ionescu, Constantin; Marmureanu, Alexandru

    2016-04-01

    Our multidisciplinary network (AeroSolSys) located in Vrancea (Curvature Carpathian Mountains) includes radon concentration monitoring in five stations. We focus on lithosphere and near surface low atmosphere phenomena using real-time information about seismicity, + / - ions, clouds, solar radiation, temperature (air, ground), humidity, atmospheric pressure, wind speed and direction, telluric currents, variations of the local magnetic field, infrasound, variations of the atmospheric electrostatic field, variations in the earth crust with inclinometers, electromagnetic activity, CO2 concentration, ULF radio wave propagation, seismo-acoustic emission, animal behavior. The main purpose is to inform the authorities about risk situation and update hazard scenarios. The radon concentration monitoring is continuously with 1 hour or 3 hours sample rate in locations near to faults in an active seismic zone characterized by intermediate depth earthquakes. Trigger algorithms include standard deviation, mean and derivative methods. We correlate radon concentration measurements with humidity, temperature and atmospheric pressure from the same equipment. In few stations we have meteorological information, too. Sometime the radon concentration has very high variations (maxim 4535 Bq/m3 from 106 Bq/m3) in short time (1 - 2 days) without being accompanied by an important earthquake. Generally the cause is the high humidity that could be generated by tectonic stress. Correlation with seismicity needs information from minimum 6 month in our case. For 10605 hours, 618 earthquakes with maxim magnitude 4.9 R, we have got radon average 38 Bq/m3 and exposure 408111 Bqh/m3 in one station. In two cases we have correlation between seismicity and radon concentration. In other one we recorded high variation because the location was in an area with multiple faults and a river. Radon can be a seismic precursor but only in a multidisciplinary network. The anomalies for short or long period of

  17. An updated review of case-control studies of lung cancer and indoor radon-Is indoor radon the risk factor for lung cancer?

    PubMed

    Sheen, Seungsoo; Lee, Keu Sung; Chung, Wou Young; Nam, Saeil; Kang, Dae Ryong

    2016-01-01

    Lung cancer is a leading cause of cancer-related death in the world. Smoking is definitely the most important risk factor for lung cancer. Radon ((222)Rn) is a natural gas produced from radium ((226)Ra) in the decay series of uranium ((238)U). Radon exposure is the second most common cause of lung cancer and the first risk factor for lung cancer in never-smokers. Case-control studies have provided epidemiological evidence of the causative relationship between indoor radon exposure and lung cancer. Twenty-four case-control study papers were found by our search strategy from the PubMed database. Among them, seven studies showed that indoor radon has a statistically significant association with lung cancer. The studies performed in radon-prone areas showed a more positive association between radon and lung cancer. Reviewed papers had inconsistent results on the dose-response relationship between indoor radon and lung cancer risk. Further refined case-control studies will be required to evaluate the relationship between radon and lung cancer. Sufficient study sample size, proper interview methods, valid and precise indoor radon measurement, wide range of indoor radon, and appropriate control of confounders such as smoking status should be considered in further case-control studies.

  18. Requirements relating to radon in the International Basic Safety Standards: information, measurement and national strategies.

    PubMed

    Colgan, P A; Boal, T; Czarwinski, R

    2013-03-01

    The fifth edition of the International Basic Safety Standards (BSS) has recently been established as Part 3 of the General Safety Requirements of the IAEA Safety Standards Series. The BSS applies to all exposure situations and to all categories of exposure. As such, the BSS addresses both occupational exposure due to radon in workplaces and public exposure due to radon in dwellings. In workplaces, exposure due to radon is treated either as a planned exposure situation or as an existing exposure situation, depending on the circumstances. With regard to exposure due to radon in dwellings, the BSS requires that general information on radon, including information on health risks and the synergy with smoking, be made available to the public and other interested parties. Countries are also required to determine whether an action plan for controlling exposure due to radon indoors is necessary, and, if so, to establish and implement such an action plan. Guidance material, covering the establishment of reference levels, national and regional radon surveys, identification of radon prone areas, building codes for new buildings, corrective actions for existing buildings, information campaigns and programme evaluation and effectiveness is currently being developed.

  19. Simultaneous measurements of indoor radon, radon-thoron progeny and high-resolution gamma spectrometry in Greek dwellings.

    PubMed

    Clouvas, A; Xanthos, S; Antonopoulos-Domis, M

    2006-01-01

    Simultaneous indoor radon, radon-thoron progeny and high-resolution in situ gamma spectrometry measurements, with portable high-purity Ge detector were performed in 26 dwellings of Thessaloniki, the second largest town of Greece, during March 2003-January 2005. The radon gas was measured with an AlphaGUARD ionisation chamber (in each of the 26 dwellings) every 10 min, for a time period between 7 and 10 d. Most of the values of radon gas concentration are between 20 and 30 Bq m(-3), with an arithmetic mean of 34 Bq m(-3). The maximum measured value of radon gas concentration is 516 Bq m(-3). The comparison between the radon gas measurements, performed with AlphaGUARD and short-term electret ionisation chamber, shows very good agreement, taking into account the relative short time period of the measurement and the relative low radon gas concentration. Radon and thoron progeny were measured with a SILENA (model 4s) instrument. From the radon and radon progeny measurements, the equilibrium factor F could be deduced. Most of the measurements of the equilibrium factor are within the range 0.4-0.5. The mean value of the equilibrium factor F is 0.49 +/- 0.10, i.e. close to the typical value of 0.4 adopted by UNSCEAR. The mean equilibrium equivalent thoron concentration measured in the 26 dwellings is EEC(thoron) = 1.38 +/- 0.79 Bq m(-3). The mean equilibrium equivalent thoron to radon ratio concentration, measured in the 26 dwellings, is 0.1 +/- 0.06. The mean total absorbed dose rate in air, owing to gamma radiation, is 58 +/- 12 nGy h(-1). The contribution of the different radionuclides to the total indoor gamma dose rate in air is 38% due to 40K, 36% due to thorium series and 26% due to uranium series. The annual effective dose, due to the different source terms (radon, thoron and external gamma radiation), is 1.05, 0.39 and 0.28 mSv, respectively.

  20. Flow chamber

    DOEpatents

    Morozov, Victor [Manassas, VA

    2011-01-18

    A flow chamber having a vacuum chamber and a specimen chamber. The specimen chamber may have an opening through which a fluid may be introduced and an opening through which the fluid may exit. The vacuum chamber may have an opening through which contents of the vacuum chamber may be evacuated. A portion of the flow chamber may be flexible, and a vacuum may be used to hold the components of the flow chamber together.

  1. Assessment of the multimedia mitigation of radon in New York.

    PubMed

    Kitto, Michael E

    2007-05-01

    Although not yet implemented, the 1996 amendments to the Safe Drinking Water Act instructed the states (or local water suppliers) to address radon concentrations in community water systems (CWS). As an alternative to reducing waterborne radon concentrations in the CWS to the maximum contaminant level (MCL) of 11 Bq L(-1), states (or individual CWS) would be permitted to develop a multimedia mitigation (MMM) program, which allowed a greater concentration (148 Bq L(-1)) of waterborne radon in the CWS, if it could be shown that an equivalent health risk reduction could be achieved by reducing indoor radon concentrations. For a MMM program to be acceptable, the U.S. Environmental Protection Agency required the health-risk reduction attained through mitigations and radon-resistant new construction (RRNC) to offset the increased health risk due to radon in community water systems above the MCL of 11 Bq L(-1). A quantitative assessment indicates that the reduction in health risk currently achieved in New York State through radon mitigations and RRNC exceeded the increase in risk associated with an alternative MCL of 148 Bq L(-1). The implementation of a MMM program in New York would result in an overall reduction in the health risk associated with exposure to radon.

  2. Measurements of radon activity concentration in mouse tissues and organs.

    PubMed

    Ishimori, Yuu; Tanaka, Hiroshi; Sakoda, Akihiro; Kataoka, Takahiro; Yamaoka, Kiyonori; Mitsunobu, Fumihiro

    2017-05-01

    The purpose of this study is to investigate the biokinetics of inhaled radon, radon activity concentrations in mouse tissues and organs were determined after mice had been exposed to about 1 MBq/m(3) of radon in air. Radon activity concentrations in mouse blood and in other tissues and organs were measured with a liquid scintillation counter and with a well-type HP Ge detector, respectively. Radon activity concentration in mouse blood was 0.410 ± 0.016 Bq/g when saturated with 1 MBq/m(3) of radon activity concentration in air. In addition, average partition coefficients obtained were 0.74 ± 0.19 for liver, 0.46 ± 0.13 for muscle, 9.09 ± 0.49 for adipose tissue, and 0.22 ± 0.04 for other organs. With these results, a value of 0.414 for the blood-to-air partition coefficient was calculated by means of our physiologically based pharmacokinetic model. The time variation of radon activity concentration in mouse blood during exposure to radon was also calculated. All results are compared in detail with those found in the literature.

  3. Measurement of HOx• production rate due to radon decay in air

    SciTech Connect

    Ding, Huiling

    1993-08-01

    Radon in indoor air may cause the exposure of the public to excessive radioactivity. Radiolysis of water vapor in indoor air due to radon decay could produce (•OH and HO2 •) that may convert atmospheric constituents to compounds of lower vapor pressure. These lower vapor pressure compounds might then nucleate to form new particles in the indoor atmosphere. Chemical amplification was used to determine HOx• production rate in indoor air caused by radon decay. Average HOx• production rate was found to be (4.31±0.07) x 105 HOx• per Rn decay per second (Bq) 3.4 to 55.0% at 22C. This work provided G(HOx•)-value, 7.86±0.13 No./100 eV in air by directly measuring [HOx•] formed from the radiolysis procedure. This G value implies that HOx• produced by radon decay in air might be formed by multiple processes and may be result of positive ion-molecule reactions, primary radiolysis, and radical reactions. There is no obvious relation between HOx• production rate and relative humidity. A laser-induced fluorescence (LIF) system has been used for •OH production rate measurement; it consists of an excimer laser, a dye laser, a frequency doubler, a gaseous fluorescence chamber, and other optical and electronic parts. This system needs to be improved to eliminate the interferences of light scattering and artificial •OH produced from the photolysis of O3/H2O.

  4. Radon in soil gas in Kosovo.

    PubMed

    Kikaj, Dafina; Jeran, Zvonka; Bahtijari, Meleq; Stegnar, Peter

    2016-11-01

    An assessment of the radiological situation due to exposure to radon and gamma emitting radionuclides was conducted in southern Kosovo. This study deals with sources of radon in soil gas. A long-term study of radon concentrations in the soil gas was carried out using the SSNTDs (CR-39) at 21 different locations in the Sharr-Korabi zone. The detectors were exposed for an extended period of time, including at least three seasonal periods in a year and the sampling locations were chosen with respect to lithology. In order to determine the concentration of the natural radioactive elements (238)U and (226)Ra, as a precursor of (222)Rn, soil samples were collected from each measuring point from a depth of 0.8 m, and measured by gamma spectrometry. The levels (Bq kg(-1)) of naturally occurring radionuclides and levels (kBq m(-3)) of radon in soil gas obtained at a depth 0.8 m of soil were: 21-53 for (226)Ra, 22-160 for (238)U and 0.295-32 for (222)Rn. With respect to lithology, the highest value for (238)U and (226)Ra were found in limestone and the highest value for (222)Rn was found in metamorphic rocks. In addition, the results showed seasonal variations of the measured soil gas radon concentrations with maximum concentration in the spring months.

  5. Procedure for the characterization of radon potential in existing dwellings and to assess the annual average indoor radon concentration.

    PubMed

    Collignan, Bernard; Powaga, Emilie

    2014-11-01

    Risk assessment due to radon exposure indoors is based on annual average indoor radon activity concentration. To assess the radon exposure in a building, measurement is generally performed during at least two months during heating period in order to be representative of the annual average value. This is because radon presence indoors could be very variable during time. This measurement protocol is fairly reliable but may be a limiting in the radon risk management, particularly during a real estate transaction due to the duration of the measurement and the limitation of the measurement period. A previous field study defined a rapid methodology to characterize radon entry in dwellings. The objective of this study was at first, to test this methodology in various dwellings to assess its relevance with a daily test. At second, a ventilation model was used to assess numerically the air renewal of a building, the indoor air quality all along the year and the annual average indoor radon activity concentration, based on local meteorological conditions, some building characteristics and in-situ characterization of indoor pollutant emission laws. Experimental results obtained on thirteen individual dwellings showed that it is generally possible to obtain a representative characterization of radon entry into homes. It was also possible to refine the methodology defined in the previous study. In addition, numerical assessments of annual average indoor radon activity concentration showed generally a good agreement with measured values. These results are encouraging to allow a procedure with a short measurement time to be used to characterize long-term radon potential in dwellings.

  6. Radon Levels in Nurseries and Primary Schools in Bragança District-Preliminary Assessment.

    PubMed

    Sousa, S I V; Branco, P T B S; Nunes, R A O; Alvim-Ferraz, M C M; Martins, F G

    2015-01-01

    Lung cancer has been associated with radon concentration even at low levels such as those found in dwellings. This study aimed to (i) determine radon diurnal variations in three nurseries and one primary school in the Bragança district (north of Portugal) and (ii) compare radon concentrations with legislated standards and assess the legislated procedures. Radon was measured in three nurseries and a primary school in a rural area with nongranite soil. Measurements were performed continuously to examine differences between occupation and nonoccupation periods. Indoor temperature and relative humidity were also measured continuously. A great variability was found in radon concentrations between the microenvironments examined. Radon concentrations surpassed by severalfold the recommended guidelines and thresholds, and excessive levels of health concern were sporadically found (361.5-753.5 Bq m(-3)). Thus, it is of importance to perform a national campaign on radon measurements and to reduce exposure.

  7. Measurement of radon concentration in some water samples belonging to some adjoining areas of Pathankot, Punjab

    NASA Astrophysics Data System (ADS)

    Kumar, Ajay; Sharma, Sumit

    2015-08-01

    The study of radon concentration was measured in some areas of Pathankot district, Punjab, India, from the health hazard point of view due to radon. The exposure to radon through drinking water is largely by inhalation and ingestion. RAD 7, an electronic solid state silicon detector (Durridgeco., USA) was used to measure the radon concentration in drinking water samples of the study area. The recorded values of radon concentration in these water samples are below the recommended limit by UNSCEAR and European commission. The recommended limit of radon concentration in water samples is 4 to 40 Bq/l given by UNSCEAR [1] and European commission has recommended the safe limit for radon concentration in water sample is 100 Bq/l [2].

  8. Measurement of radon concentration in some water samples belonging to some adjoining areas of Pathankot, Punjab

    SciTech Connect

    Kumar, Ajay Sharma, Sumit

    2015-08-28

    The study of radon concentration was measured in some areas of Pathankot district, Punjab, India, from the health hazard point of view due to radon. The exposure to radon through drinking water is largely by inhalation and ingestion. RAD 7, an electronic solid state silicon detector (Durridgeco., USA) was used to measure the radon concentration in drinking water samples of the study area. The recorded values of radon concentration in these water samples are below the recommended limit by UNSCEAR and European commission. The recommended limit of radon concentration in water samples is 4 to 40 Bq/l given by UNSCEAR [1] and European commission has recommended the safe limit for radon concentration in water sample is 100 Bq/l [2].

  9. Radon Resources for Home Buyers and Sellers

    MedlinePlus

    ... provide feedback, or report a problem. Radon Indoor Air Quality Home Page Radon Home Local Radon Zones and State Contact Information Individuals and Families Radon Publications Home Buyers and ... Air Bed Bugs Chemicals and Toxics Climate Change Environmental ...

  10. Radon progeny particle growth in the simulated environment of the respiratory tract

    SciTech Connect

    George, A.C.

    1993-10-01

    To determine the magnitude of induced particle growth of radon progeny a simulator was constructed to create and maintain conditions similar to those prevailing in the respiratory tract. During testing, the conditioned metal simulator was connected to a radon chamber in which different test aerosols were mixed with radon progeny. The exhaust rate from the radon chamber and through the simulator test chamber ranged from 0.1 to 0.15 m{sup 3}/min. The residence time of the radon progeny attached to the test aerosol in the air space of the simulator ranged from 1.0 to 1.5 min. To measure particle growth, alternate tests were made in the simulator and in a second test chamber identical to the simulator but without the water. Particle size was measured with diffusion batteries and growth was determined from the difference in the activity median diameters of the radon progeny measured in the two test chambers. The results from tests using different aerosols showed average particle growth factors of 1.5 for room air, 1.8 when an electrical heater is operating, 1.7 when a methane gas burner is on, 2.0 while a kerosene lamp is lit, 1.6 while a candle is burning, 1.2 during cigar smoking, 2.8 when a NaCl generator is on, 1.0 in the presence of wax aerosol, and 1.05 in the presence of very young radon progeny from freshly filtered radon gas. This study shows that, as a result of particle growth, deposition in the tracheobronchial region of the respiratory tract and the radiation dose from radon progeny attached to ordinary room air aerosol is reduced by an average value of 25%. 21 refs., 2 figs., 3 tabs.

  11. An improved silicon PIN diode based portable radon monitor

    NASA Astrophysics Data System (ADS)

    Ashokkumar, P.; Sahoo, B. K.; Topkar, A.; Raman, A.; Babu, D. A. R.; Sharma, D. N.; Mayya, Y. S.

    2013-05-01

    A low budget radon monitor has been developed using silicon PIN diode. Sensitivity factor of this monitor is observed to be relatively high over the other similar monitors. This is achieved by incorporation of a hemispherical mesh in the sampling chamber, thereby accelerating the electro-deposition of charged polonium atoms on the detector surface. Its performance has been tested successfully against reference equipment.

  12. A study on concentration measurements of radon-222 (uranium series) and radon-220 (thoron series) emitted to the atmosphere from tex (cementitious), red brick, and ecocarat among construction materials

    NASA Astrophysics Data System (ADS)

    Ju, Yong-Jin; Ryu, Young-Hwan; Jang, Hyon-Chol; Dong, Kyung-Rae; Chung, Woon-Kwan; Cho, Jae-Hwan; Kweon, Dae Cheol; Goo, Eun-Hoe; Lee, Jae-Seung; Park, Cheol-Soo; Lim, Chang-Seon

    2012-04-01

    The aim of this study was to measure, compare and analyze the air concentration of radon emitted to the atmosphere from a range of construction materials, such as tex (cementitious), red brick and ecocarat. The study methodology involved the use of continuous radon monitoring equipment (RTM 1688-2) to measure the concentrations of radon and thoron (Rn-220) contained in tex (cementitious), red brick and ecocarat. Among the three samples, tex showed the highest levels of radon and thoron emissions. When the radon emission concentration was estimated based on the materials required for construction per unit area (3.3 m2) in an actual building, tex showed the highest levels of radon and thoron emissions, with ecocarat exhibiting the lowest. Overall, this method is suitable for examining the effects of radon and for reducing the personal radiation exposure dose. Governments should be active in publicizing and encouraging the use of construction materials with lower levels of radon emission.

  13. Radon reduction and radon monitoring in the NEMO experiment

    SciTech Connect

    Nachab, A.

    2007-03-28

    The first data of the NEMO 3 neutrinoless double beta decay experiment have shown that the radon can be a non negligible component of the background. In order to reduce the radon level in the gas mixture, it has been necessary first to cover the NEMO 3 detector with an airtight tent and then to install a radon-free air factory. With the use of sensitive radon detectors, the level of radon at the exit of the factory and inside the tent is continuously controlled. These radon levels are discussed within the NEMO 3 context.

  14. Radon Optical Processing in Radon Space.

    DTIC Science & Technology

    1986-06-15

    yields one line through the three-dimensional Fourier transform 1. Radon, J., " Uber die Bestimmung von Funktiontn of the three-dimensional function (3...Alamos, New Mexico , April 11-15. 1983.a 6. W. G. Wee, "Application of projection techniques to image image. Figure 1(a) has approximately 8.0 bits/pixel

  15. Alteration in carboxyhemoglobin concentrations during exposure to 9 ppm carbon monoxide for 8 hours at sea level and 2134 m altitude in a hypobaric chamber

    SciTech Connect

    Horvath, S.M.; Bedi, J.F. )

    1989-10-01

    Seventeen non-smoking young men served as subjects to determine the alteration in carboxyhemoglobin (COHb) concentrations during exposure to 0 or 9 ppm carbon monoxide for 8 hours (CO) at sea level or an altitude of 2134 meters (7000 feet) in a hypobaric chamber. Nine subjects rested during the exposure and 8 exercised for 10 minutes of each exposure hour at a mean ventilation of 25 L (BTPS). All subjects performed a maximal aerobic capacity test at the completion of their respective exposures. Carboxyhemoglobin concentrations fell in all subjects during their exposures to 0 ppm CO at sea level or 2134 m. During the 8-h exposures to 9 ppm CO, COHb rose linearly from approximately 0.2 percent to 0.7 percent. No significant differences in uptake were found whether the subjects were resting or intermittently exercising during their 8-h exposures. COHb levels attained were similar at both sea level and 2134 m. Maximal aerobic capacity was reduced approximately 7-10 percent consequent to altitude exposure during 0 ppm CO exposures. These values were not altered following exposure for 8 h to 9 ppm CO in either the resting or exercising subjects.

  16. Detailed diesel exhaust characteristics including particle surface area and lung deposited dose for better understanding of health effects in human chamber exposure studies

    NASA Astrophysics Data System (ADS)

    Wierzbicka, Aneta; Nilsson, Patrik T.; Rissler, Jenny; Sallsten, Gerd; Xu, Yiyi; Pagels, Joakim H.; Albin, Maria; Österberg, Kai; Strandberg, Bo; Eriksson, Axel; Bohgard, Mats; Bergemalm-Rynell, Kerstin; Gudmundsson, Anders

    2014-04-01

    Several diesel exhaust (DE) characteristics, comprising both particle and gas phase, recognized as important when linking with health effects, are not reported in human chamber exposure studies. In order to understand effects of DE on humans there is a need for better characterization of DE when performing exposure studies. The aim of this study was to determine and quantify detailed DE characteristics during human chamber exposure. Additionally to compare to reported DE properties in conducted human exposures. A wide battery of particle and gas phase measurement techniques have been used to provide detailed DE characteristics including the DE particles (DEP) surface area, fraction and dose deposited in the lungs, chemical composition of both particle and gas phase such as NO, NO2, CO, CO2, volatile organic compounds (including aldehydes, benzene, toluene) and polycyclic aromatic hydrocarbons (PAHs). Eyes, nose and throat irritation effects were determined. Exposure conditions with PM1 (<1 μm) mass concentration 280 μg m-3, number concentration 4 × 105 cm-3 and elemental to total carbon fraction of 82% were generated from a diesel vehicle at idling. When estimating the lung deposited dose it was found that using the size dependent effective density (in contrast to assuming unity density) reduced the estimated respiratory dose by 132% by mass. Accounting for agglomerated structure of DEP prevented underestimation of lung deposited dose by surface area by 37% in comparison to assuming spherical particles. Comparison of DE characteristics reported in conducted chamber exposures showed that DE properties vary to a great extent under the same DEP mass concentration and engine load. This highlights the need for detailed and standardized approach for measuring and reporting of DE properties. Eyes irritation effects, most probably caused by aldehydes in the gas phase, as well as nose irritation were observed at exposure levels below current occupational exposure limit

  17. Measurement of Radon Concentration in Selected Houses in Ibadan, Nigeria

    NASA Astrophysics Data System (ADS)

    Usikalu, M. R.; Olatinwo, V.; Akpochafor, M.; Aweda, M. A.; Giannini, G.; Massimo, V.

    2017-05-01

    Radon is a natural radioactive gas without colour or odour and tasteless. The World Health Organization (WHO) grouped radon as a human lung carcinogen. For this reason, there has been a lot of interest on the effects of radon exposure to people all over the world and Nigeria is no exception. The aim of this study is to investigate the radon concentration in selected houses in three local government areas of Ibadan. The indoor radon was measured in both mud and brick houses. Fifty houses were considered from the three Local government areas. A calibrated portable continuous radon monitor type (RAD7) manufactured by Durridge company was used for the measurement. A distance of 100 to 200 m was maintained between houses in all the locations. The living room was kept closed during the measurements. The mean radon concentration measured in Egbeda is 10.54 ±1.30 Bqm -3; Lagelu is 16.90 ± 6.31 Bqm -3 and Ona-Ara is 17.95 ± 1.72 Bqm -3. The mean value of the annual absorbed dose and annual effective dose for the locations in the three local government areas was 0.19 mSvy-1 and 0.48 mSvy-1 respectively. The radon concentration for location 10 in Ono-Ara local government exceeded the recommended limit. However, the overall average indoor radon concentration of the three local governments was found to be lower than the world average value of 40 Bqm -3. Hence, there is need for proper awareness about the danger of radon accumulation in dwelling places.

  18. 30 CFR 57.5040 - Exposure records.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) The operator shall calculate and record complete individual exposures to concentrations of radon... concentration of airborne radon daughters for each active working area. (2) Where uranium is not mined—the complete individual exposure of all mine personnel working in active working areas with radon daughter...

  19. 30 CFR 57.5040 - Exposure records.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) The operator shall calculate and record complete individual exposures to concentrations of radon... concentration of airborne radon daughters for each active working area. (2) Where uranium is not mined—the complete individual exposure of all mine personnel working in active working areas with radon daughter...

  20. 30 CFR 57.5040 - Exposure records.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) The operator shall calculate and record complete individual exposures to concentrations of radon... concentration of airborne radon daughters for each active working area. (2) Where uranium is not mined—the complete individual exposure of all mine personnel working in active working areas with radon daughter...

  1. Radon and lung cancer risk: taking stock at the millenium.

    PubMed Central

    Samet, J M; Eradze, G R

    2000-01-01

    Radon is a well-established human carcinogen for which extensive data are available, extending into the range of exposures experienced by the general population. Mounting epidemiologic evidence on radon and lung cancer risk, now available from more than 20 different studies of underground miners and complementary laboratory findings, indicates that risks are linear in exposure without threshold. Radon is also a ubiquitous indoor air pollutant in homes, and risk projections imply that radon is the second leading cause of lung cancer after smoking. Recommended control strategies in the United States and other countries, which include testing of most homes and mitigation of those exceeding guideline levels, have been controversial. Further research is needed, drawing on molecular and cellular approaches and continuing the follow-up of the underground miner cohorts, and scientists should work toward constructing mechanistically based models that combine epidemiologic and experimental data to yield risk estimates with enhanced certainty. Images Figure 1 Figure 2 PMID:10931781

  2. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres. Progress report, May 1, 1993--January 31, 1994

    SciTech Connect

    Hopke, P.K.

    1993-01-01

    Progress is reported on the chemical and physical behavior of the {sup 218}Po atom immediately following its formation by the alpha decay of radon. Two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical processes that affect the progeny`s atmospheric behavior and studies in actual indoor environments to develop a better assessment of the exposure of the occupants of that space to the size and concentration of the indoor radioactive aerosol. The specific tasks addressed were to determine the formation rates of {center_dot}OH radicals formed by the radiolysis of air following radon decay, to examine the formation of particles by the radiolytic oxidation of substances like SO{sub 2}, ethylene, and H{sub 2}S to lower vapor pressure compounds and determine the role of gas phase additives such as H{sub 2}O and NH{sub 3} in determining the particle size, to measure the rate of ion-induced nucleation using a thermal diffusion cloud chamber, and to measure the neutralization rate of {sup 218}PoO{sub x}{sup +} in O{sub 2} at low radon concentrations. Initial measurements were conducted of the activity size distributions in actual homes with occupants present so that the variability of the indoor activity size distributions can be assessed with respect to indoor aerosol sources and general lifestyle variations of the occupants. A prospective study of the utility of measurement of deposited {sup 210}Pb embedded in glass surfaces as a measure of the long-term, integrated exposure of the population to radon are described. Methodology was developed to determine the hygroscopicity of the indoor aerosol so that the changes in deposition efficiency of the radioactive indoor aerosol with hygroscopic growth in the respiratory tract can be assessed.

  3. Indoor Radon Measurement in Van

    SciTech Connect

    Kam, E.; Osmanlioglu, A. E.; Celebi, N.; Dogan, I.

    2007-04-23

    In this study, indoor radon concentrations obtained from the radon surveys conducted in the Van. Radon monitoring was performed by applying a passive, time-integrating measuring technique. For this purpose, CR-39 nuclear track detectors were installed in dwellings for 2 months. After the monitoring period, detectors were collected. In order to make the alpha tracks visible, chemical etching was applied to the exposed detectors. Nuclear track numbers and the corresponding indoor radon concentrations were determined. Annual effective dose equivalents and the risk probabilities caused by indoor radon inhalation were calculated, and the found results compared with the indoor radon concentrations' data measured in different provinces of Turkey.

  4. Recommendations for Radon Research

    EPA Pesticide Factsheets

    This report, undertaken upon the initiative of the Radiation Advisory Committee, is the first Science Advisory Board report to look at the entire field of radon research and the contribution additional scientific understanding can make on EPA's policies.

  5. Health Risk of Radon

    MedlinePlus

    ... related lung cancer in women. Top of Page Biological Effects of Ionizing Radiation (BEIR) VI Report: "The ... of Sciences' (NAS) latest report on radon, the Biological Effects of Ionizing Radiation (BEIR) VI Report (1999). ...

  6. Experimental animal studies of radon and cigarette smoke

    SciTech Connect

    Cross, F.T.; Dagle, G.E.; Gies, R.A.; Smith, L.G.; Buschbom, R.L.

    1992-12-31

    Cigarette-smoking is a dominant cause of lung cancer and confounds risk assessment of exposure to radon decay products. Evidence in humans on the interaction between cigarette-smoking and exposure to radon decay products, although limited, indicates a possible synergy. Experimental animal data, in addition to showing synergy, also show a decrease or no change in risk with added cigarette-smoke exposures. This article reviews previous animal data developed at Compagnie Generale des Matieres Nucleaires and Pacific Northwest Laboratory (PNL) on mixed exposures to radon and cigarette smoke, and highlights new initiation-promotion-initiation (IPI) studies at PNL that were designed within the framework of a two-mutation carcinogenesis model. Also presented are the PNL exposure system, experimental protocols, dosimetry, and biological data observed to date in IPI animals.

  7. Headspace stir bar sorptive extraction-gas chromatography/mass spectrometry characterization of the diluted vapor phase of cigarette smoke delivered to an in vitro cell exposure chamber.

    PubMed

    Kaur, Navneet; Cabral, Jean-Louis; Morin, André; Waldron, Karen C

    2011-01-14

    Advanced smoke generation systems, such as the Borgwaldt RM20S(®) smoking machine used in combination with the BAT exposure chamber, allow for the generation, dilution and delivery of fresh cigarette smoke to cell or tissue cultures for in vitro cell culture analyses. Recently, our group confirmed that the Borgwaldt RM20S(®) is a reliable tool to generate and deliver repeatable and reproducible exposure concentrations of whole smoke to in vitro cultures. However, the relationship between dose and diluted smoke components found within the exposure chamber has not been characterized. The current study focused on the development of a headspace stir bar sorptive extraction (HSSE) method to chemically characterize some of the vapor phase components of cigarette smoke generated by the Borgwaldt RM20S(®) and collected within a cell culture exposure chamber. The method was based on passive sampling within the chamber by HSSE using a Twister™ stir bar. Following exposure, sorbed analytes were recovered using a thermal desorption unit and a cooled injection system coupled to gas chromatograph/mass spectrometry for identification and quantification. Using the HSSE method, sixteen compounds were identified. The desorption parameters were assessed using ten reference compounds and the following conditions led to the maximal response: desorption temperature of 200°C for 2 min with cryofocussing temperature of -75°C. During transfer of the stir bars to the thermal desorption system, significant losses of analytes were observed as a function of time; therefore, the exposure-to-desorption time interval was kept at the minimum of 10±0.5 min. Repeatability of the HSSE method was assessed by monitoring five reference compounds present in the vapor phase (10.1-12.9% RSD) and n-butyl acetate, the internal standard (18.5% RSD). The smoke dilution precision was found to be 17.2, 6.2 and 11.7% RSD for exposure concentrations of 1, 2 and 5% (v/v) cigarette vapor phase in air

  8. RESIDENTIAL RADON AND BIRTH DEFECTS: A POPULATION-BASED ASSESSMENT

    PubMed Central

    Langlois, Peter H; Lee, MinJae; Lupo, Philip J; Rahbar, Mohammad H; Cortez, Ruben K

    2015-01-01

    BACKGROUND Associations have been reported between maternal radiation exposure and birth defects. No such studies were found on radon. Our objective was to determine if there is an association between living in areas with higher radon levels and birth defects. METHODS The Texas Birth Defects Registry provided data on all birth defects from 1999–2009 from the entire state. Mean radon levels by geologic region came from the Texas Indoor Radon Survey. The association between radon and birth defects was estimated using multilevel mixed effect Poisson regression. RESULTS Birth defects overall were not associated with residential radon levels. Of the 100 other birth defect groups with at least 500 cases, 14 were significantly elevated in areas with high mean radon level in crude analyses, and 9 after adjustment for confounders. Cleft