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Sample records for radon progeny exposure

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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

  10. 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.

  11. 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

  12. 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.

  13. 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/.

  14. Reduction of Radon Progeny in Indoor Air.

    DTIC Science & Technology

    1986-03-01

    methods that can be used to lower radon progeny concentra- tions in homes. V.- Radon in Indoor Air. Radon -222 occurs midway through the Uranium -238...as metals and remain at the site of their formation, radon is a noble gas and is thus able to diffuse away from its forma- tion site. It is through... radon progeny reduction by forced ventilation alone was evaluated because the 1/4 inch metal pre-filter screens for this air cleaner remained installed

  15. 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.

  16. 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

  17. 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.

  18. [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.

  19. 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.

  20. 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.

  1. Microdosimetry of radon progeny: Application to risk assessment

    SciTech Connect

    Fisher, D.R.; Hui, T.E.; James, A.C. ); Bond, V.P. )

    1990-01-01

    We developed methods for calculating radiation doses to individual cells and cell nuclei of human bronchial epithelium from radon and progeny for specified levels of exposure, breathing rates, equilibrium factors, unattached fraction of progeny, and other factors that are important in radon dosimetry. If we also know which cells are likely precursors for cancer, and we also know their locations in the respiratory tract, we then may calculate the statistical probability that these cells are irradiated by alpha particles, the number of single alpha-particle hits, and the spectrum of doses delivered as a probability density in specific energy.

  2. 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.

  3. 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.

  4. 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}.

  5. 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.

  6. 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

  7. Comparative analysis of radon, thoron and thoron progeny concentration measurements.

    PubMed

    Janik, Miroslaw; Tokonami, Shinji; Kranrod, Chutima; Sorimachi, Atsuyuki; Ishikawa, Tetsuo; Hosoda, Masahiro; McLaughlin, James; Chang, Byung-Uck; Kim, Yong Jae

    2013-07-01

    This study examined correlations between radon, thoron and thoron progeny concentrations based on surveys conducted in several different countries. For this purpose, passive detectors developed or modified by the National Institute of Radiological Sciences (NIRS) were used. Radon and thoron concentrations were measured using passive discriminative radon-thoron detectors. Thoron progeny measurements were conducted using the NIRS-modified detector, originally developed by Zhuo and Iida. Weak correlations were found between radon and thoron as well as between thoron and thoron progeny. The statistical evaluation showed that attention should be paid to the thoron equilibrium factor for calculation of thoron progeny concentrations based on thoron measurements. In addition, this evaluation indicated that radon, thoron and thoron progeny were independent parameters, so it would be difficult to estimate the concentration of one from those of the others.

  8. 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.

  9. Deposition of radon progeny in nonhuman primate nasal airways

    SciTech Connect

    Yeh, H.C.; Cheng, Y.S.; Su, Y.F. . Inhalation Toxicology Research Inst.); Morgan, K.T. )

    1991-01-01

    Information on aerosol deposition patterns in the human respiratory tract is needed to improve health risk estimates for exposure to airborne radon progeny. To investigate this, deposition of {sup 220}Rn progeny in Rhesus monkey nasal casts was examined. A substantial fraction of the inhaled ultrafine particles are deposited in the nasal cast. Deposition efficiency increases with decreasing particle size, reaching a maximum value of 80% for particles 1.7 nm in diameter. Breathing flow rate has a minimal effect on deposition efficiency. Deposition efficiencies for particles smaller than 100 nm in diameter are similar for monkey and human nasal casts. Equations based on turbulent diffusion can be fitted to these data for either inspirational or expirational flow. These mathematical expressions will be useful for modifying the inhaled particle deposition and dosimetry models. 20 refs., 9 figs., 1 tab (MHB)

  10. 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.

  11. RADON PROGENY AS AN EXPERIMENTAL TOOL FOR DOSIMETRY OF NANOAEROSOLS

    SciTech Connect

    Ruzer, Lev; Ruzer, Lev S.; Apte, Michael G.

    2008-02-25

    The study of aerosol exposure and dosimetry measurements and related quantitation of health effects are important to the understanding of the consequences of air pollution, and are discussed widely in the scientific literature. During the last 10 years the need to correlate aerosol exposure and biological effects has become especially important due to rapid development of a new, revolutionary industry ?-- nanotechnology. Nanoproduct commerce is predicted to top $1 trillion by 2015. Quantitative assessment of aerosol particle behavior in air and in lung deposition, and dosimetry in different parts of the lung, particularly for nanoaerosols, remains poor despite several decades of study. Direct measurements on humans are still needed in order to validate the hollow cast, animal studies, and lung deposition modeling. We discuss here the use of nanoscale radon decay products as an experimental tool in the study of local deposition and lung dosimetry for nanoaerosols. The issue of the safe use of radon progeny in such measurements is discussed based on a comparison of measured exposure in 3 settings: general population, miners, and in a human experiment conducted at the Paul Scherer Institute (PSI) in Switzerland. One of the properties of radon progeny is that they consist partly of 1 nm radioactive particles called unattached activity; having extremely small size and high diffusion coefficients, these particles can be potentially useful as radioactive tracers in the study of nanometer-sized aerosols. We present a theoretical and experimental study of the correlation between the unattached activity and aerosol particle surface area, together with a description of its calibration and method for measurement of the unattached fraction.

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

    SciTech Connect

    Hopke, P.K.

    1992-07-01

    This report covers the second year of the 28 month grant current grant to Clarkson University to study the chemical and physical behavior of the polonium 218 atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity 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. Two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical process 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. This report describes the progress toward achieving these objectives.

  13. Morphology of respiratory tract lesions in rats exposed to radon progeny

    SciTech Connect

    Dagle, G.E.; Cross, F.T.; Gies, R.A.

    1992-12-31

    We will discuss the morphologic features of lesions in the respiratory tract of rats exposed to radon and radon progeny. Groups of male Wister rats were exposed to from 10 to 1000 working levels (WL) of radon progeny in the presence of less than 1 to about 15 mg m{sup {minus}3} uranium ore dust. Cumulative exposures ranged from 20 to approximately 10,000 working level months (WLM). Higher exposure levels produced radiation pneumonitis characterized by interstitial fibrosis, associated with alveolar epithelial cell hyperplasia and accumulations of alveolar macrophages containing phagocytosed uranium ore dust. Nodular fibrosis and alveolar proteinosis were correlated with deposits of uranium ore dust. Vesicular emphysema also occurred at higher exposure levels. Pulmonary adenomatosis appeared to be a preneoplastic lesion; it was composed of nodular proliferation of bronchioloalveolar epithelium without disruption of the general architecture of the parenchyma. At exposure levels where rats lived longer than 1 y, lung tumors and a few tumors of the nasal cavity developed. The principal lung tumors were pulmonary adenomas, bronchioloalveolar carcinomas, papillary adenocarcinomas, epidermoid carcinomas, and adenosquamous carcinomas. Occasionally, malignant mesotheliomas and sarcomas were also present. The malignant lung tumors were characterized by invasion and occasionally metastasized to regional lymph nodes. Lower exposure rates produced more tumors, generally of different histologic types, and more fatal tumors than higher exposure rates. The similarity to relationships of human radon progeny exposure as far as incidence and types of lung tumors establish the validity of this animal model for studying radon carcinogenesis in humans.

  14. Deposition of radon progeny in nonhuman primate nasal airways

    SciTech Connect

    Yeh, H.C.; Cheng, Y.S.; Morgan, K.T.

    1992-12-31

    Radon progeny are usually associated with ultrafine particles ranging in diameter from 0.001 to 0.005 {mu}m for {open_quotes}unattached{close_quotes} progeny and from 0.005 to 0.2 {mu}m for those attached to indoor aerosols. To assess the health effects of inhaling indoor radon progeny, it is necessary to study the regional deposition of these inhaled ultrafine particles. Laboratory animals are often used in studies of the toxicity of inhaled particles and vapors. Information on the deposition of particles larger than 0.2 {mu}m in the nasal passages of laboratory animals is available; however, there is little information on the deposition of particles smaller than 0.2 {mu}m. In this report, we describe the use of nasal casts of a rhesus monkey to measure total deposition of ultrafine aerosols, including unattached {sup 220}Rn progeny, in a unidirectional-flow inhalation exposure system. Deposition data were obtained for monodisperse silver aerosols with particle sizes ranging from 0.005 to 0.2 {mu}m, at several inspiratory and expiratory flow rates that represented normal breathing as well as hypo- and hyperventiliation. In addition, we studied the deposition of unattached {sup 22-}Rn progeny, at particle sizes from 0.001 to 0.003 {mu}m. The deposition efficiency decreased with increasing particle size, indicating that diffusion was the dominant deposition mechanism. The effect of flow rate was essentially negligible. Based on assumptions that turbulent flow and complete mixing of aerosols occur in the nasal airways, a general equation E = 1-exp (-a D{sup b}Q{sup c}) for d{sub p} {<=} 0.2 {mu}m, was derived, where E is the deposition efficiency, d{sub p} is the particle diameter, D is the diffusion coefficient, and Q is the flow rate. Constants a, b, and c are estimated from experimental data, for either inspiration or expiration. This mathematical expression will be useful for making modifications to both deposition and dosimetry models.

  15. Modeling surface backgrounds from radon progeny plate-out

    SciTech Connect

    Perumpilly, G.; Guiseppe, V. E.; Snyder, N.

    2013-08-08

    The next generation low-background detectors operating deep underground aim for unprecedented low levels of radioactive backgrounds. The surface deposition and subsequent implantation of radon progeny in detector materials will be a source of energetic background events. We investigate Monte Carlo and model-based simulations to understand the surface implantation profile of radon progeny. Depending on the material and region of interest of a rare event search, these partial energy depositions can be problematic. Motivated by the use of Ge crystals for the detection of neutrinoless double-beta decay, we wish to understand the detector response of surface backgrounds from radon progeny. We look at the simulation of surface decays using a validated implantation distribution based on nuclear recoils and a realistic surface texture. Results of the simulations and measured α spectra are presented.

  16. Field investigation of surface-deposited radon progeny as a possible predictor of the airborne radon progeny dose rate.

    PubMed

    Sun, Kainan; Steck, Daniel J; Field, R William

    2009-08-01

    The quantitative relationships between radon gas concentration, the surface-deposited activities of various radon progeny, the airborne radon progeny dose rate, and various residential environmental factors were investigated through actual field measurements in 38 selected Iowa houses occupied by either smokers or nonsmokers. Airborne dose rate was calculated from unattached and attached potential alpha energy concentrations (PAECs) using two dosimetric models with different activity-size weighting factors. These models are labeled Pdose and Jdose, respectively. Surface-deposited 218Po and 214Po were found significantly correlated to radon, unattached PAEC, and both airborne dose rates (p < 0.0001) in nonsmoking environments. However, deposited 218Po was not significantly correlated to the above parameters in smoking environments. In multiple linear regression analysis, natural logarithm transformation was performed for airborne dose rate as the dependent variable, as well as for radon and deposited 218Po and 214Po as predictors. An interaction effect was found between deposited 214Po and an obstacle in front of the Retrospective Reconstruction Detector (RRD) in predicting dose rate (p = 0.049 and 0.058 for Pdose and Jdose, respectively) for nonsmoking environments. After adjusting for radon and deposited radon progeny effects, the presence of either cooking, usage of a fireplace, or usage of a ceiling fan significantly, or marginally significantly, reduced the Pdose to 0.65 (90% CI 0.42-0.996), 0.54 (90% CI 0.28-1.02), and 0.66 (90% CI 0.45-0.96), respectively. For Jdose, only the usage of a ceiling fan significantly reduced the dose rate to 0.57 (90% CI 0.39-0.85). In smoking environments, deposited 218Po was a significant negative predictor for Pdose (RR 0.68, 90% CI 0.55-0.84) after adjusting for long-term 222Rn and environmental factors. A significant decrease of 0.72 (90% CI 0.64-0.83) in the mean Pdose was noted, after adjusting for the radon and radon

  17. Field Investigation of the Surface-deposited Radon Progeny as a Possible Predictor of the Airborne Radon Progeny Dose Rate

    PubMed Central

    Sun, Kainan; Steck, Daniel J.; Field, R. William

    2009-01-01

    The quantitative relationships between radon gas concentration, the surface-deposited activities of various radon progeny, the airborne radon progeny dose rate, and various residential environmental factors were investigated through actual field measurements in 38 selected Iowa houses occupied by either smokers or nonsmokers. Airborne dose rate was calculated from unattached and attached potential alpha energy concentrations (PAECs) using two dosimetric models with different activity-size weighting factors. These models are labeled Pdose and Jdose, respectively. Surface-deposited 218Po and 214Po were found significantly correlated to radon, unattached PAEC, and both airborne dose rates (p < 0.0001) in nonsmoking environments. However, deposited 218Po was not significantly correlated to the above parameters in smoking environments. In multiple linear regression analysis, natural logarithm transformation was performed for airborne dose rate as the dependent variable, as well as for radon and deposited 218Po and 214Po as predictors. An interaction effect was found between deposited 214Po and an obstacle in front of the Retrospective Reconstruction Detector (RRD) in predicting dose rate (p = 0.049 and 0.058 for Pdose and Jdose, respectively) for nonsmoking environments. After adjusting for radon and deposited radon progeny effects, the presence of either cooking, usage of a fireplace, or usage of a ceiling fan significantly, or marginal significantly, reduced the Pdose to 0.65 (90% CI 0.42–0.996), 0.54 (90% CI 0.28–1.02) and 0.66 (90% CI 0.45–0.96), respectively. For Jdose, only the usage of a ceiling fan significantly reduced the dose rate to 0.57 (90% CI 0.39–0.85). In smoking environments, deposited 218Po was a significant negative predictor for Pdose (RR 0.68, 90% CI 0.55–0.84) after adjusting for long-term 222Rn and environmental factors. A significant decrease of 0.72 (90% CI 0.64–0.83) in the mean Pdose was noted, after adjusting for the radon and

  18. 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.

  19. Radiation dose due to radon and thoron progeny inhalation in high-level natural radiation areas of Kerala, India.

    PubMed

    Omori, Yasutaka; Tokonami, Shinji; Sahoo, Sarata Kumar; Ishikawa, Tetsuo; Sorimachi, Atsuyuki; Hosoda, Masahiro; Kudo, Hiromi; Pornnumpa, Chanis; Nair, Raghu Ram K; Jayalekshmi, Padmavaty Amma; Sebastian, Paul; Akiba, Suminori

    2017-03-20

    In order to evaluate internal exposure to radon and thoron, concentrations for radon, thoron, and thoron progeny were measured for 259 dwellings located in high background radiation areas (HBRAs, outdoor external dose: 3-5 mGy y(-1)) and low background radiation areas (control areas, outdoor external dose: 1 mGy y(-1)) in Karunagappally Taluk, Kerala, India. The measurements were conducted using passive-type radon-thoron detectors and thoron progeny detectors over two six-month measurement periods from June 2010 to June 2011. The results showed no major differences in radon and thoron progeny concentrations between the HBRAs and the control areas. The geometric mean of the annual effective dose due to radon and thoron was calculated as 0.10 and 0.44 mSv, respectively. The doses were small, but not negligible compared with the external dose in the two areas.

  20. 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

  1. Model for assessing radiation dose to epithelial cells of the human respiratory tract from radon progeny

    SciTech Connect

    Fisher, D.R.; Hui, T.E.; James, A.C.

    1990-07-01

    A computational model was developed to evaluate radiation doses to sensitive cells from exposure to radon progeny throughout human bronchial epithelium. The model incorporated current information on nasal and oral filtration efficiencies for unattached radon progeny, characteristics of bronchial deposition by diffusive and inertial processes, mucous clearance and possible transfer of radon progeny to the airway epithelium, locations of target nuclei of secretory and basal cells in different regions of the bronchial tree epithelium, and other features. The model is useful for evaluating absorbed doses to various populations of target cell nuclei, the associated microdosimetric probability densities in specific energy, and the likelihood that target nuclei are hit one or more times by alpha-particle tracks. The model was applied to extrapolating lung cancer risks observed in underground miners to the general population exposed to low-level radon progeny in indoor home environments. The effect of increasing exposure rates by one and two orders of magnitude in both environments was modeled to determine the frequency of radiation events in target cell nuclei. The implications of dosimetric modeling for lung cancer risk analysis were also examined. 28 refs., 5 figs., 5 tabs.

  2. 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.

  3. Radon progeny in hydrometeors at the earth's surface.

    PubMed

    Voltaggio, M

    2012-07-01

    During atmospheric thermal inversions, dew and hoarfrost concentrate gamma emitting radionuclides of the short-lived (222)Rn progeny ((214)Pb and (214)Bi), causing an increase in the total natural gamma background from the ground. To highlight this phenomenon, a volcanic zone of high (222)Rn flux was studied during the winter season 2010-11. High-specific short-lived radon progeny activities up to 122 Bq g(-1) were detected in hydrometeors forming at the earth's surface (ESHs), corresponding to a mean increase of up to 17 % of the normal gamma background value. A theoretical model, depending on radon flux from soil and predicting the radon progeny concentrations in hydrometeors forming at the ESHs is presented. The comparison between model and field data shows a good correspondence. Around nuclear power plants or in nuclear facilities that use automatic NaI or CsI total gamma spectroscopy systems for monitoring radioactive contamination, hydrometeors forming at the ESHs in sites with a high radon flux could represent a relevant source of false alarms of radioactive contamination.

  4. Impact of haze-fog days to radon progeny equilibrium factor and discussion of related factors.

    PubMed

    Hou, Changsong; Shang, Bing; Zhang, Qingzhao; Cui, Hongxing; Wu, Yunyun; Deng, Jun

    2015-11-01

    The equilibrium factor F between radon and its short-lived progenies is an important parameter to estimate radon exposure of humans. Therefore, indoor and outdoor concentrations of radon and its short-lived radon progeny were measured in Beijing area using a continuously measuring device, in an effort to obtain information on the F value. The results showed that the mean values of F were 0.58 ± 0.13 (0.25-0.95, n = 305) and 0.52 ± 0.12 (0.31-0.91, n = 64) for indoor and outdoor, respectively. The indoor F value during haze-fog days was higher than the typical value of 0.4 recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation, and it was also higher than the values of 0.47 and 0.49 reported in the literature. A positive correlation was observed between indoor F values and PM2.5 concentrations (R (2) = 0.71). Since 2013, owing to frequent heavy haze-fog events in Beijing and surrounding areas, the number of the days with severe pollution remains at a high level. Future studies on the impact of the ambient fine particulate matter on indoor radon progeny equilibrium factor F could be important.

  5. Monitoring of short-lived radon progeny in mines.

    PubMed

    Skubacz, K; Bywalec, T

    2003-01-01

    Obligatory measurements of the potential alpha energy concentration of short-lived radon progeny have been performing in the Polish underground mines since 1989. In consideration of economic aspects, an attempt was made from the very beginning to combine it with measurements of the dust concentration. Therefore the developed measuring units were an integral part of the dust samplers complying with the requirements of the State Mining Authority to apply them in underground mines. This way the developed devices could fulfil two measurement tasks simultaneously: measurement of the dust concentration and potential alpha energy concentration of short-lived radon progeny. The new device based on the thermoluminescence detectors is able to cooperate with the dust samplers made by the SKC company and equipped with a cyclone making it possible to operate them constantly for one working day. The lower limit of detection was equal about 0.04 microJ m(-3) at a 95% confidence level and 1 h pumping.

  6. Prediction of Lung Cells Oncogenic Transformation for Induced Radon Progeny Alpha Particles Using Sugarscape Cellular Automata

    PubMed Central

    Baradaran, Samaneh; Maleknasr, Niaz; Setayeshi, Saeed; Akbari, Mohammad Esmaeil

    2014-01-01

    Background Alpha particle irradiation from radon progeny is one of the major natural sources of effective dose in the public population. Oncogenic transformation is a biological effectiveness of radon progeny alpha particle hits. The biological effects which has caused by exposure to radon, were the main result of a complex series of physical, chemical, biological and physiological interactions. The cellular and molecular mechanisms for radon-induced carcinogenesis have not been clear yet. Methods Various biological models, including cultured cells and animals, have been found useful for studying the carcinogenesis effects of radon progeny alpha particles. In this paper, sugars cape cellular automata have been presented for computational study of complex biological effect of radon progeny alpha particles in lung bronchial airways. The model has included mechanism of DNA damage, which has been induced alpha particles hits, and then formation of transformation in the lung cells. Biomarkers were an objective measure or evaluation of normal or abnormal biological processes. In the model, the metabolism rate of infected cell has been induced alpha particles traversals, as a biomarker, has been followed to reach oncogenic transformation. Results The model results have successfully validated in comparison with “in vitro oncogenic transformation data” for C3H 10T1/2 cells. This model has provided an opportunity to study the cellular and molecular changes, at the various stages in radiation carcinogenesis, involving human cells. Conclusion It has become well known that simulation could be used to investigate complex biomedical systems, in situations where traditional methodologies were difficult or too costly to employ. PMID:25250147

  7. Radon: Chemical and physical states of radon progeny. Final technical report

    SciTech Connect

    Castleman, A.W. Jr.

    1996-12-31

    The evolving chemical and physical form of radon progeny influence their transport to the bioreceptor and the extent to which that receptor can take up these species into various tissues. When first born following radioactive decay processes, the potentially deleterious radon progeny undergo various physical and chemical transformations as they transcend from a highly charged to a neutral state, and interact with various constituents of the environment. These transformations impact on the extent to which the radon progeny become associated with aerosol particles on the one hand, and their ultimate chemical form that is available for uptake in the biosystem, on the other. The program, which originally commenced in 1987, dealt with the basic chemistry and physics of radon progeny and hence impacted on several themes of importance to the DOE/OHER radon program. One of these is dose response, which is governed by the physical forms of the radon progeny, their transport to the bioreceptor and the chemical forms that govern their uptake. The second theme had to do with cellular responses, one of the major issues motivating the work. It is well known that various sizes of ions and molecules are selectively transported across cell membrane to differing degrees. This ultimately has to do with their chemical and physical forms, charge and size. The overall objective of the work was threefold: (1) quantifying the mechanisms and rates of the chemical and physical transformation; (2) ascertaining the ultimate chemical forms, and (3) determining the potential interactions of these chemical species with biological functional groups to ascertain their ultimate transport and incorporation within cells.

  8. 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.

  9. Recent developments in radon metrology: new aspects in the calibration of radon, thoron and progeny devices.

    PubMed

    Röttger, A; Honig, A

    2011-05-01

    Due to the importance of reliable measurements of radon activity concentration, one of the past developments in metrology was applied to the field of radon, thus meeting two basic needs: (1) the harmonisation of metrology within the scope of the mutual recognition arrangement, an arrangement drawn up by the International Committee of Weights and Measures for the mutual recognition of national standards and of calibrations issued by national metrology institutes and (2) the increased demands of the European Atomic Energy Community (EURATOM) directive, transferred into national radiation protection regulations with regard to natural radioactivity and its quality-assured measurements. This paper gives an overview of typical technical procedures in the radon-measuring technique group of PTB, covering all aspects of reference atmospheres (primary standards) for radon, thoron and their respective progenies.

  10. RADON AND PROGENY ALPHA-PARTICLE ENERGY ANALYSIS USING NUCLEAR TRACK METHODOLOGY

    SciTech Connect

    Espinosa Garcia, Guillermo; Golzarri y Moreno, Dr. Jose Ignacio; Bogard, James S

    2008-01-01

    A preliminary procedure for alpha energy analysis of radon and progeny using Nuclear Track Methodology (NTM) is described in this paper. The method is based on the relationship between alpha-particle energies deposited in polycarbonate material (CR-39) and the track size developed after a well-established chemical etching process. Track geometry, defined by parameters such as major or minor diameters, track area and overall track length, is shown to correlate with alpha-particle energy over the range 6.00 MeV (218Po) to 7.69 MeV (214Po). Track features are measured and the data analyzed automatically using a digital imaging system and commercial PC software. Examination of particle track diameters in CR-39 exposed to environmental radon reveals a multi-modal distribution. Locations of the maxima in this distribution are highly correlated with alpha particle energies of radon daughters, and the distributions are sufficiently resolved to identify the radioisotopes. This method can be useful for estimating the radiation dose from indoor exposure to radon and its progeny.

  11. The Influence of Radon (Gas and Progeny) and Weather Conditions on Ambient Dose Equivalent Rate.

    PubMed

    Márquez, J L; Benito, G; Saez, J C; Navarro, N; Alvarez, A; Quiñones, J

    2016-08-13

    The purpose of this study is to identify the influence of radon (gas and progeny) on the ambient dose equivalent rate measured at the reference station ESMERALDA, where continuous measurements of the ambient dose equivalent rate (every 10 min) combined with activity concentration measurements of radon gas and radon progeny as well as meteorological parameters have been collected. This study has been performed using a correlation study based on a principal components analysis and the Spearman's rank correlation coefficient.

  12. First detection of radon progeny recoil tracks by MIMAC

    NASA Astrophysics Data System (ADS)

    Riffard, Q.; Santos, D.; Guillaudin, O.; Bosson, G.; Bourrion, O.; Bouvier, J.; Descombes, T.; Fourel, C.; Muraz, J.-F.; Lebreton, L.; Maire, D.; Colas, P.; Ferrer-Ribas, E.; Giomataris, I.; Busto, J.; Fouchez, D.; Brunner, J.; Tao, C.

    2017-06-01

    The MIMAC experiment is a μ-TPC project for directional dark matter search. Directional detection strategy is based on the measurement of the WIMP flux anisotropy due to the solar system motion with respect to the dark matter halo. The main purpose of MIMAC project is the measurement of nuclear recoil energy and 3D direction from the WIMP elastic scattering on target nuclei. Since June 2012 a bi-chamber prototype is operating at the Modane underground laboratory. In this paper, we report the first ionization energy and 3D track observations of NRs produced by the radon progeny. This measurement shows the capability of the MIMAC detector and opens the possibility to explore the low energy recoil directionality signature.

  13. Evaluation of indoor aerosol control devices and their effects on radon progeny concentrations. Revision

    SciTech Connect

    Sextro, R.G.; Offermann, F.J.; Nazaroff, W.W.; Nero, A.V.; Revzan, K.L.; Yater, J.

    1984-11-01

    Eleven portable air cleaning devices have been evaluated for control of indoor concentrations of respirable particles, and their concomitant effects on radon progeny concentrations have been investigated. The experiments were conducted in a room-size chamber using cigarette smoke and radon injection from an external source. Of the devices examined the electrostatic precipitators and extended surface filters had significant particle removal rates, while the particle removal rates for several small panel-filters, an ion-generator, and a pair of mixing fans were found to be essentially negligible. The evaluation of radon progeny control produced similar results; the air cleaners which were effective in removing particles were also effective in reducing radon progeny concentrations. At the low particle concentrations, deposition of the unattached radon progeny on room surfaces was found to be a significant removal mechanism. Deposition rates of attached and unattached progeny have been estimated from these data, and were used to calculate the equilibrium factors for total and unattached progeny concentrations as a function of particle concentration. While particle removal reduces total airborne radon progeny concentrations, the relative alpha decay dose to the lungs appears to change very little as the particle concentration decreases due to the greater radiological importance of unattached progeny.

  14. Carcinogenic risk of non-uniform alpha-particle irradiation in the lungs: Radon progeny effects at bronchial bifurcations

    SciTech Connect

    Hoffmann, W.; Crawford-Brown, D.J.; Menache, M.G.; Martonen, T.B.

    1992-01-01

    The combined effect of enhanced deposition and reduced clearance at bronchial bifurcations leads to increased radon progeny doses within branching sites compared to uniformly distributed activity within a given airway generation. A multi-stage carcinogenesis model was used to predict the probability of lung cancer induction at different sites of the bronchial region. For relatively low radon progeny exposures, lung cancer risk is significantly higher in bifurcation zones, particularly at carinal ridges, than along tubular segments. At sufficiently high exposures, however, lung cancer risk is highest in the tubular portions of a generation. This suggests that the common assumption of a uniform dose distribution provides realistic risk estimates for high uranium miner exposures, but may underestimate lung cancer risk at low, environmental exposures. If concomitant exposure to cigarette smoke is factored into the risk analysis in a multiplicative fashion, then the effect related to risk inhomogeneity becomes even more pronounced.

  15. Study of the atmospheric chemistry of radon progeny in laboratory and real indoor atmospheres. Progress report, July 1, 1991--June 30, 1992

    SciTech Connect

    Hopke, P.K.

    1992-07-01

    This report covers the second year of the 28 month grant current grant to Clarkson University to study the chemical and physical behavior of the polonium 218 atom immediately following its formation by the alpha decay of radon. Because small changes in size for activity 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. Two areas of radon progeny behavior are being pursued; laboratory studies under controlled conditions to better understand the fundamental physical and chemical process 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. This report describes the progress toward achieving these objectives.

  16. Radon, thoron and their progeny levels in some dwellings of northern Haryana, India using SSNTDs

    NASA Astrophysics Data System (ADS)

    Saini, R. S.; Nain, Mahabir; Chauhan, R. P.; Kishore, Nawal; Chakarvarti, S. K.

    2009-08-01

    Radon pollution is an important global problem of radiation hygiene. Radon and its progeny are the major contributors in the radiation dose received by general population of the world. Keeping this in mind the environmental monitoring of radon, thoron and their progeny in some dwellings of northern part of Haryana state of India has been carried out. The radon-thoron twin dosimeter cups were used for the study. The aim of the study is the possible health risk assessment in the dwellings under consideration.

  17. 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.

  18. 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...

  19. Control of respirable particles and radon progeny with portable air cleaners

    SciTech Connect

    Offermann, F.J.; Sextro, R.G.; Fisk, W.J.; Nazaroff, W.W.; Nero, A.V.; Revzan, K.L.; Yater, J.

    1984-02-01

    Eleven portable air cleaning devices have been evaluated for control of indoor concentrations of respirable particles and radon progeny. Following injection of cigarette smoke and radon in a room-size chamber, decay rates for particles and radon progeny concentrations were measured with and without air cleaner operation. Particle concentrations were obtained for total number concentration and for number concentration by particle size. In tests with no air cleaner the natural decay rate for cigarette smoke was observed to be 0.2 hr/sup -1/. Air cleaning rates for particles were found to be negligible for several small panel-filters, a residential ion-generator, and a pair of mixing fans. The electrostatic precipitators and extended surface filters tested had significant particle removal rates, and a HEPA-type filter was the most efficient air cleaner. The evaluation of radon progeny control produced similar results; the air cleaners which were effective in removing particles were also effective in removing radon progeny. At low particle concentrations plateout of the unattached radon progeny is an important removal mechanism. Based on data from these tests, the plateout rate for unattached progeny was found to be 15 hr/sup -1/. The unattached fraction and the overall removal rate due to deposition of attached and unattached nuclides have been estimated for each radon decay product as a function of particle concentration. While air cleaning can be effective in reducing total radon progeny, concentrations of unattached radon progeny can increase with increasing air cleaning. 39 references, 26 figures, 9 tables.

  20. MEASUREMENT OF RADON, THORON AND THEIR PROGENY CONCENTRATIONS IN THE DWELLINGS OF PAURI GARHWAL, UTTARAKHAND, INDIA.

    PubMed

    Joshi, Veena; Dutt, Sanjay; Yadav, Manjulata; Mishra, Rosaline; Ramola, R C

    2016-10-01

    It is well known that inhalation of radon, thoron and their progeny contributes more than 50 % of natural background radiation dose to human being. The time-integrated passive measurements of radon, thoron and their progeny concentrations were carried out in the dwellings of Pauri Garhwal, Uttarakhand, India. The measurements of radon and thoron concentrations were performed by LR-115 detector-based single-entry pin-hole dosemeter, while for the measurement of progeny concentrations, LR-115 deposition-based direct radon and thoron progeny sensors technique was used. The experimental 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.

  1. 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.

  2. 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

  3. 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.

  4. 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.

  5. 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.

  6. A new technique for measuring the concentrations of airborne radon progeny by using an imaging plate.

    PubMed

    Zhang, H; Chen, B; Zhao, C; Zhuo, W

    2012-11-01

    A new technique was developed for measuring the concentrations of airborne radon progeny by using an imaging plate (IP). The concentrations of radon progeny collected on the sampling filter were measured with the IP at 2-5-, 6-20- and 21-30-min intervals after sampling, and the alpha disintegrations were automatically counted by a self-developed image analysis software. To reduce the overlapping impact on alpha counts, a plastic separator with a 0.5-mm thickness was set between the sampling filter and the IP. The lower limit of detection for the equilibrium equivalent concentration of radon was estimated to be ∼3.5 Bq m(-3) for a 10-min sampling at 10 l min(-1). Comparison experiments showed that results measured with the new technique were well consistent with those measured with the alpha spectrometer. It indicates that the new technique is a useful method for accurate measurements of airborne radon progeny concentrations.

  7. Comparative study of various techniques for environmental radon, thoron and progeny measurements.

    PubMed

    Ramola, R C; Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Gusain, G S; Mishra, Rosaline; Sahoo, S K; Tokonami, S

    2015-11-01

    Long-term average concentrations of radon, thoron and progeny were measured in normal and high background radiation areas in India using different techniques. Radon, thoron and progeny concentrations were measured using Raduet, Pin-Hole dosimeter, deposition-based CR-39 and deposition-based direct radon/thoron progeny sensor (DRPS/DTPS) detector system. All these techniques were used at a same time inside an individual dwelling. Radon concentration was recorded higher than thoron concentration in Garhwal Homes (NBRA) while thoron concentration was found relatively higher in the houses of Chhatarpur area (HBRA) in Odisha, India. The values measured with the CR-39 detector-based technique were found comparable with the values measured with the LR-115 detector-based technique. The comparisons of results using various techniques and their usefulness in radiation measurements are discussed in detail.

  8. Deposition patterns of molecular phase radon progeny (218Po) in lung bifurcations.

    PubMed

    Kinsara, A A; Loyalka, S K; Tompson, R V; Miller, W H; Holub, R F

    1995-03-01

    Indoor air contamination by radon and its decay products is currently the focus of considerable attention and is considered by many to be the greatest potential cause of lung cancer in the human environment next to smoking. The bifurcations of the human respiratory tract are regions in which enhanced local deposition of particles (hot spots) can occur. These hot spots are important in estimating the risk from radon exposure but existing mathematical models do not characterize them accurately. In this study, radon progeny in the molecular size range were sampled through an aluminium model of a lung bifurcation. The parent and secondary tube diameters used correspond to the third and fourth generations in Weibel's lung model. Steady state, nominally laminar flows were used in the study. Deposition was measured along the inside, outside, top, and bottom walls of the secondary tubes. Experimental results indicate that the deposition along the inside wall is noticeably higher than that along the other walls. The results also show that along the inside, top, and bottom walls the deposition has its overall maximum at the carina. Other maxima are also observed along the secondary tubes downstream from the carina.

  9. Inhalation dose due to radon, thoron, and progenies in dwellings of a hill station.

    PubMed

    Sivakumar, R

    2017-02-01

    The general public spends a major portion of their time in an indoor environment and hence receives a considerable amount of radiation. Knowledge about indoor radiation is important in order to arrive at the actual effective dose received by residents. The indoor radon, thoron, and progeny concentrations observed in the present study were found to vary with seasons of a given year. The highest and lowest indoor average radon, thoron, and progeny levels were observed during winter and summer seasons, respectively. The concentrations of indoor radon, thoron, and progenies were found to vary with the type of houses. The highest (222)Rn, (220)Rn, and progeny concentrations were observed in mud houses and the lowest values were recorded in wooden houses. The indoor (222)Rn concentration correlated well with concentration of its grandparent (238)U in underlying soil with a correlation coefficient of 0.87. The correlation between indoor (220)Rn and (232)Th in the underlying soil was found to be 0.64. The estimated effective doses received by the general public in the present study due to indoor radon and thoron were 1.49 ± 0.49 and 1.30 ± 0.53 mSv/year, respectively. The annual effective doses due to radon and thoron progenies were estimated as 0.76 ± 0.27 and 0.47 ± 0.23 mSv/year, respectively. The contributions from (222)Rn, (220)Rn, and corresponding progenies to the annual effective doses received were 37, 32, 19, and 12%, respectively. The general public living in the study area receives an inhalation dose of 4.02 mSv/year due to indoor radon, thoron, and progenies, which were found to be less than the action limit of ICRP 2009.

  10. 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.

  11. Investigation of the air pressure characteristics influencing the variability of radon gas and radon progeny in domestic vernacular buildings.

    PubMed

    Marley, F

    2001-07-01

    Analysis of time-series data sets collected in vernacular buildings linked with radium source bedrock has identified a number of internal and external pressure characteristics linking meteorological parameters with the variability of radon gas and its progeny. The buildings' cellars built into the bedrock associated with the radium source have relatively high levels of radon concentration. These cellars have essentially stable microclimatic conditions, unlike the ground and upper levels of the buildings. Comparative radon concentration data collected from various comparable buildings suggest the need to distinguish between short and longer-term influences on radon concentrations. Water vapor pressure is inferred to be a principal determinant of the short-term variability of radon gas concentrations. Barometric pressure is suggested as determining the trend or general longer-term level of radon. Both of these pressure components are related to temperature. Wind speed appears to have a dual influence on radon variability: directly, through wind pressure relative to the ground and building structure particularly associated with low-pressure weather regimes; and indirectly, through changes to the water vapor pressure component.

  12. Assessing the deposition of radon progeny from a uranium glass necklace.

    PubMed

    Hansen, M F; Moss, G R

    2015-06-01

    Could jewellery made from uranium glass beads pose an increased risk to skin cancer? The literature Eatough (Alpha-particle dosimetry for the basal layer of the skin and the radon progeny (218)Po and (214)Po. Phys. Med. Biol. 1997; 42: 1899-1911.) suggests that the alphas from the short-lived radon daughters, (218)Po and (214)Po, may reach the basal layer of the epidermis, which is believed to be important in the induction of skin cancers. The deposition of the alphas from the (218)Po and (214)Po daughters was investigated using PADC detector material. The expectation would be that no alpha particles would penetrate through the dead skin layer, assuming the average of 70 microns used in radiation protection, but the skin around the collar bone could potentially be thinner than the assumed average. It should be noticed that by inserting a slice of pig skin in between the necklace and the PADC, no great excess of alpha tracks were seen after 1 week of exposure in the freezer. There was, however, a clear signal through the pig skin from beta particles, confirming the potential of a uranium bead necklace posing a health risk.

  13. The biological effectiveness of radon-progeny alpha particles. V. Comparison of oncogenic transformation by accelerator-produced monoenergetic alpha particles and by polyenergetic alpha particles from radon progeny.

    PubMed

    Miller, R C; Richards, M; Brenner, D J; Hall, E J; Jostes, R; Hui, T E; Brooks, A L

    1996-07-01

    Generation of estimates of risk caused by exposure to radon in the home, either from miner data or from A-bomb data, requires several scaling factors such as for dose, dose rate and radiation quality, and possible synergisms. Such scaling factors are best developed from laboratory-based studies. Two possible sources of alpha particles for such studies are (1) a polyenergetic spectrum, generated directly by radon and its progeny, or (2) a series of monoenergetic alpha particles. We compare here the results of oncogenic transformation from studies using both systems. At the Columbia University Radiological Research Accelerator Facility (RARAF), C3H 10T1/2 cells were irradiated with alpha particles of various energies, with defined LETs from 70 to 200 keV/mum. At Pacific Northwest Laboratory, cells from the same stock were exposed to alpha particles from radon gas and its progeny, which were in equilibrium with the culture medium. There was good agreement between the results of oncogenic transformation experiments using the two different exposure systems. Apart from the experimental transformation frequencies themselves, such a comparison requires (1) reliable dosimetry at both facilities and (2) estimated LET distributions for the polyenergetic alpha-particle irradiator. Thus this good agreement gives some confirmation to the technique which is used to fold together oncogenic transformation rates from monoenergetic alpha particles to yield a predicted rate for a spectrum of alpha particles.

  14. 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

  15. Long-term measurements of residential radon, thoron, and thoron progeny concentrations around the Chhatrapur placer deposit, a high background radiation area in Odisha, India.

    PubMed

    Omori, Yasutaka; Prasad, Ganesh; Sorimachi, Atsuyuki; Sahoo, Sarata Kumar; Ishikawa, Tetsuo; Vidya Sagar, Devulapalli; Ramola, Rakesh Chand; Tokonami, Shinji

    2016-10-01

    The Chhatrapur placer deposit is found in a high background radiation area which has been recently identified on the southeastern coast of India. Previously, some geochemical studies of this area were carried out to assess external dose from radionuclides-bearing heavy mineral sands. In this study, radon, thoron and thoron progeny concentrations were measured in about 100 dwellings during three seasons (autumn-winter, summer, and rainy) in a 10- to 12-month period and annual doses due to inhalation of them were evaluated. The measurements were made by passive-type radon-thoron discriminative detectors and thoron progeny detectors in which solid state nuclear track detectors were deployed. The results show that radon and thoron concentrations differ by one order of magnitude depending on exposure periods, while thoron progeny concentration is nearly constant throughout the year. Since thorium-rich sand is distributed in the studied area, exposure to thoron is equal to, or exceeds, exposure to radon and is not negligible for dose evaluation. Based on the measurements, doses due to inhalation of radon and thoron are evaluated as 0.1-1.6 mSv y(-1) and 0.2-3.8 mSv y(-1), respectively. The total dose is 0.8-4.6 mSv y(-1), which is the same order of magnitude as the worldwide value. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Filter for on-line air monitor unaffected by radon progeny and method of using same

    DOEpatents

    Phillips, Terrance D.; Edwards, Howard D.

    1999-01-01

    An apparatus for testing air having contaminants and radon progeny therein. The apparatus includes a sampling box having an inlet for receiving the air and an outlet for discharging the air. The sampling box includes a filter made of a plate of sintered stainless steel. The filter traps the contaminants, yet allows at least a portion of the radon progeny to pass therethrough. A method of testing air having contaminants and radon progeny therein. The method includes providing a testing apparatus that has a sampling box with an inlet for receiving the air and an outlet for discharging the air, and has a sintered stainless steel filter disposed within said sampling box; drawing air from a source into the sampling box using a vacuum pump; passing the air through the filter; monitoring the contaminants trapped by the filter; and providing an alarm when a selected level of contaminants is reached. The filter traps the contaminants, yet allows at least a portion of the radon progeny to pass therethrough.

  17. Indoor radon progeny aerosol size measurements in urban, suburban, and rural regions

    SciTech Connect

    Tu, K.W.; Knutson, E.O.; George, A.C. )

    1991-01-01

    By using direct and indirect methods, the authors conducted size distribution measurements of radon progeny particles in a variety of indoor environments in urban, suburban, and rural areas. The radon progeny particle size distribution owing to indoor activities has two definable source categories: (1) gas combustion from stoves and kerosene heaters - particles were found to be smaller than 0.1 {mu}m in diameter, mostly in the range 0.02-0.08 {mu}m; and (2) cigarette smoking and food frying - particles were found to be larger, in the size range 0.1-0.2 {mu}m. The radon progeny particle size distribution, without significant indoor activities, such as cooking, was found to be larger in rural areas than in urban or suburban areas. The modal diameters of the size spectra in the rural areas were two to three times larger than those in urban or suburban areas, around 0.3-0.4 bs. 0.1-0.2 {mu}m. Results obtained by applying the attachment theory to the measured number-weighted size spectra from an electrical aerosol size analyzer support this finding. These results, if confirmed by more extensive studies, will be useful for the assessment of the risk from the inhalation of radon progeny in various indoor environments.

  18. Study on the influence of CR-39 detector size on radon progeny detection in indoor environments

    NASA Astrophysics Data System (ADS)

    Pereira, L. A.; Hadler, J. C.; Lixandrão F., A. L.; Guedes, S.; Takizawa, R. H.

    2014-11-01

    It is well known that radon daughters up to 214Po are the real contaminants to be considered in case of indoor radon contamination. Assemblies consisting of 6 circular bare sheets of CR-39, a nuclear track detector, with radius varying from 0.15 to 1.2 cm were exposed far from any material surface for periods of approximately 6 months in 13 different indoor rooms (7 workplaces and 6 dwellings), where ventilation was moderate or poor. It was observed that track density was as greater as smaller was the detector radius. Track density data were fitted using an equation deduced based on the assumption that the behavior of radon and its progeny in the air was described by Fick's Law, i.e., when the main mechanism of transport of radon progeny in the air is diffusion. As many people spend great part of their time in closed or poorly ventilated environments, the confirmation they present equilibrium between radon and its progeny is an interesting start for dosimetric calculations concerning this contamination.

  19. Study on the influence of CR-39 detector size on radon progeny detection in indoor environments

    SciTech Connect

    Pereira, L. A.; Hadler, J. C.; Lixandrão F, A. L.; Guedes, S.; Takizawa, R. H.

    2014-11-11

    It is well known that radon daughters up to {sup 214}Po are the real contaminants to be considered in case of indoor radon contamination. Assemblies consisting of 6 circular bare sheets of CR-39, a nuclear track detector, with radius varying from 0.15 to 1.2 cm were exposed far from any material surface for periods of approximately 6 months in 13 different indoor rooms (7 workplaces and 6 dwellings), where ventilation was moderate or poor. It was observed that track density was as greater as smaller was the detector radius. Track density data were fitted using an equation deduced based on the assumption that the behavior of radon and its progeny in the air was described by Fick's Law, i.e., when the main mechanism of transport of radon progeny in the air is diffusion. As many people spend great part of their time in closed or poorly ventilated environments, the confirmation they present equilibrium between radon and its progeny is an interesting start for dosimetric calculations concerning this contamination.

  20. Characteristics of indoor radon and its progeny in a Japanese dwelling while using air appliances.

    PubMed

    Pornnumpa, C; Tokonami, S; Sorimachi, A; Kranrod, C

    2015-11-01

    Characteristics of radon and its progeny were investigated in different air conditions by turning four types of indoor air appliances on and off in a two-story concrete Japanese dwelling. The four appliances were air conditioner, air cleaner, gas heater and cooker hood. The measurements were done using two devices: (1) a Si-based semiconductor detector for continuous measurement of indoor radon concentration and (2) a ZnS(Ag) scintillation counting system for equilibrium-equivalent radon concentration. Throughout the entire experiment, the cooker hood was the most effective in decreasing indoor radon concentration over a long period of time and the less effective was the air conditioner, while the air cleaner and gas heater did not affect the concentration of radon. However, the results measured in each air condition will differ according to the lifestyles and activities of the inhabitants. In this study, indoor radon and its progeny in a Japanese dwelling will be characterised by the different air conditions. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Measurement of radon progenies using the Timepix detector.

    PubMed

    Bulanek, Boris; Jilek, Karel; Cermak, Pavel

    2014-07-01

    After an introduction of Timepix detector, results of these detectors with silicon and cadmium telluride detection layer in assessment of activity of short-lived radon decay products are presented. They were collected on an open-face filter by means of one-grab sampling method from the NRPI radon chamber. Activity of short-lived radon decay products was estimated from measured alpha decays of 218,214Po. The results indicate very good agreement between the use of both Timepix detectors and an NRPI reference instrument, continuous monitor Fritra 4. Low-level detection limit for EEC was estimated to be 41 Bq m(-3) for silicon detection layer and 184 Bq m(-3) for CdTe detection layer, respectively.

  2. Analysis of radon and thoron progeny measurements based on air filtration.

    PubMed

    Stajic, J M; Nikezic, D

    2015-02-01

    Measuring of radon and thoron progeny concentrations in air, based on air filtration, was analysed in order to assess the reliability of the method. Changes of radon and thoron progeny activities on the filter during and after air sampling were investigated. Simulation experiments were performed involving realistic measuring parameters. The sensitivity of results (radon and thoron concentrations in air) to the variations of alpha counting in three and five intervals was studied. The concentration of (218)Po showed up to be the most sensitive to these changes, as was expected because of its short half-life. The well-known method for measuring of progeny concentrations based on air filtration is rather unreliable and obtaining unrealistic or incorrect results appears to be quite possible. A simple method for quick estimation of radon potential alpha energy concentration (PAEC), based on measurements of alpha activity in a saturation regime, was proposed. Thoron PAEC can be determined from the saturation activity on the filter, through beta or alpha measurements.

  3. Effect of indoor-generated airborne particles on radon progeny dynamics.

    PubMed

    Trassierra, C Vargas; Stabile, L; Cardellini, F; Morawska, L; Buonanno, G

    2016-08-15

    In order to investigate the interaction between radon progeny and particles, an experimental campaign was carried out in a radon chamber at the Italian National Institute of Ionizing Radiation Metrology, quantifying the amount of attached and unattached radon daughters present in air, as well as the equilibrium factor in the presence of particles generated through indoor sources. A fixed radon concentration was maintained, while particles were generated using incense sticks, mosquito coils and gas combustion. Aerosols were characterized in terms of particle concentrations and size distributions. Simultaneously, radon concentration and attached/unattached potential alpha energy concentration in the air were continuously monitored by two different devices, based on alpha spectroscopy techniques. The presence of particles was found to affect the attached fraction of radon decay products, in such a way that the particles acted as a sink for radionuclides. In terms of sources which emit large particles (e.g. incense, mosquito coils), which greatly increase particle surface area concentrations, the Equilibrium Factor was found to double with respect to the background level before particle generation sessions. On the contrary, the radon decay product dynamics were not influenced by gas combustion processes, mainly due to the small surface area of the particles emitted. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Investigation of the influences of atmospheric conditions on the variability of radon and radon progeny in buildings

    NASA Astrophysics Data System (ADS)

    Marley, Frederick

    Analysis of time-series data sets, collected in vernacular buildings and workplaces linked with radium source bedrock has identified a number of internal and external pressure characteristics linking meteorological parameters with the variability of radon gas and its progeny. The cellars in these buildings are excavated from the bedrock associated with the radium source and have relatively high levels of radon concentration along with largely stable microclimatic conditions, which differ from those of the buildings' ground and upper levels. In workplace environments cyclical characteristics are apparent, associated with heating and ventilation related to working hours. Comparative radon concentration data, collected within buildings and similarities identified between buildings, suggest the need to distinguish between short and longer-term influences. From a range of comparative data studied, water vapour pressure, a partial pressure of barometric pressure, is indicated as a principal determinant of the short-term variability of radon gas concentrations, with barometric pressure determining the trend or general longer term level, both linked to temperature. Wind speed appears to have the potential for a dual influence on radon variability: directly, through wind pressure differences and indirectly, through changes to the water vapour component.

  5. The portable device for continual measurement of radon progenies on filter using the detector Timepix.

    PubMed

    Bulanek, Boris; Hulka, Jiri; Jilek, Karel; Stekl, Ivan

    2015-06-01

    In this article, a portable device was presented for continual measuring of equilibrium equivalent concentration (EEC) of (222)Rn based on the Timepix detector with 300-µm-thick active layer. In order to have a portable device, a filtration head was developed for collecting short-lived radon progenies attached on aerosols. The short-lived progenies are estimated from analysing alphas from decay of (218,214)Po from Millipore filter after termination of filtration. Comparison with beta measurement was done as well. The dependence of EEC on an air flow and filtration time was studied. The low-level detection limit for EEC was estimated from the last 10 min of 3-h decay measurement and was found in the range of 40-70 Bq m(-3). EEC was measured in National Radiation Protection Institute radon chamber, and results were compared with the commercial detector Fritra4.

  6. Dosimetry of localized accumulations of cigarette smoke and radon progeny at bifurcations

    SciTech Connect

    Martonen, T.B.; Hofmann, W.

    1991-01-01

    The work focuses upon deposition and clearance processes affecting cigarette smoke particles and radon progeny within surrogate airway models, replica casts and the human lung. As shall be demonstrated, 'cloud motion' for mainstream cigarette smoke can produce locations of enhanced deposition not experienced with dilute aerosols composed of like-sized particles. These sites of concentrated deposits occur at airway bifurcations, especially at the inclusive carinal ridges.

  7. Radon-222, sup 222 Rn progeny, and sup 220 Rn progeny levels in 70 houses

    SciTech Connect

    Dudney, C.S.; Hawthorne, A.R.; Wallace, R.G.; Reed, R.P. )

    1990-03-01

    A year-long, multipollutant, indoor air quality study involving 70 occupied houses in four states was completed in 1987. All of the houses included in the study had a partial or complete basement with a concrete slab floor and block walls. On an approximately quarterly schedule, integrating monitors for short-lived Rn progeny, nitrogen dioxide, formaldehyde, and water vapor were exposed for 1 wk in each house on both the basement and main floors. At the beginning of the study, a pair of alpha-track detectors were placed on top of the refrigerator in the kitchen (or some other sampling location on the main floor) and at a location in the basement. One detector at each location was left in place for a year while the other detector was retrieved and replaced once every 3-mo period. In addition, short-term measurements of Rn and {sup 222}Rn progeny were made at all sampling locations once per quarter. In this study, comparisons were made between: (1) seasonal and annual averages, (2) summer and winter averages, (3) living-area and basement results, (4) {sup 222}Rn and {sup 220}Rn progeny, and (5) short- and long-term measurements. The Rn and Rn progeny concentrations in houses near Huntsville, AL were found to be well above recommended action levels (150 Bq m-3). For houses near Birmingham, AL, summer Rn concentrations were found to exceed winter concentrations, whereas for the other houses in the study, winter concentrations exceeded summer concentrations. Potential alpha energy concentrations (PAEC) from {sup 220}Rn progeny were found to be generally less than PAEC from {sup 222}Rn.

  8. Radon-222, 222Rn progeny, and 220Rn progeny levels in 70 houses.

    PubMed

    Dudney, C S; Hawthorne, A R; Wallace, R G; Reed, R P

    1990-03-01

    A year-long, multipollutant, indoor air quality study involving 70 occupied houses in four states was completed in 1987. All of the houses included in the study had a partial or complete basement with a concrete slab floor and block walls. On an approximately quarterly schedule, integrating monitors for short-lived Rn progeny, nitrogen dioxide, formaldehyde, and water vapor were exposed for 1 wk in each house on both the basement and main floors. At the beginning of the study, a pair of alpha-track detectors were placed on top of the refrigerator in the kitchen (or some other sampling location on the main floor) and at a location in the basement. One detector at each location was left in place for a year while the other detector was retrieved and replaced once every 3-mo period. In addition, short-term measurements of Rn and 222Rn progeny were made at all sampling locations once per quarter. In this study, comparisons were made between: (1) seasonal and annual averages, (2) summer and winter averages, (3) living-area and basement results, (4) 222Rn and 220Rn progeny, and (5) short- and long-term measurements. The Rn and Rn progeny concentrations in houses near Huntsville, AL were found to be well above recommended action levels (150 Bq m-3). For houses near Birmingham, AL, summer Rn concentrations were found to exceed winter concentrations, whereas for the other houses in the study, winter concentrations exceeded summer concentrations. Potential alpha energy concentrations (PAEC) from 220Rn progeny were found to be generally less than PAEC from 222Rn.

  9. 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.

  10. 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

  11. 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.

  12. 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.

  13. A review of lung-to-blood absorption rates for radon progeny.

    PubMed

    Marsh, J W; Bailey, M R

    2013-12-01

    The International Commission on Radiological Protection (ICRP) Publication 66 Human Respiratory Tract Model (HRTM) treats clearance of materials from the respiratory tract as a competitive process between absorption into blood and particle transport to the alimentary tract and lymphatics. The ICRP recommended default absorption rates for lead and polonium (Type M) in ICRP Publication 71 but stated that the values were not appropriate for short-lived radon progeny. This paper reviews and evaluates published data from volunteer and laboratory animal experiments to estimate the HRTM absorption parameter values for short-lived radon progeny. Animal studies showed that lead ions have two phases of absorption: ∼10 % absorbed with a half-time of ∼15 min, the rest with a half-time of ∼10 h. The studies also indicated that some of the lead ions were bound to respiratory tract components. Bound fractions, f(b), for lead were estimated from volunteer and animal studies and ranged from 0.2 to 0.8. Based on the evaluations of published data, the following HRTM absorption parameter values were derived for lead as a decay product of radon: f(r) = 0.1, s(r) = 100 d(-1), s(s) = 1.7 d(-1), f(b) = 0.5 and s(b) = 1.7 d(-1). Effective doses calculated assuming these absorption parameter values instead of a single absorption half-time of 10 h with no binding (as has generally been assumed) are only a few per cent higher. However, as there is some conflicting evidence on the absorption kinetics for radon progeny, dose calculations have been carried out for different sets of absorption parameter values derived from different studies. The results of these calculations are discussed.

  14. RADON AND PROGENY SOURCED DOSE ASSESSMENT OF SPA EMPLOYEES IN BALNEOLOGICAL SITES.

    PubMed

    Uzun, Sefa Kemal; Demiröz, Işık

    2016-09-01

    This study was conducted in the scope of IAEA project with the name 'Establishing a Systematic Radioactivity Survey and Total Effective Dose Assessment in Natural Balneological Sites' (TUR/9/018), at the Health Physics department of Sarayköy Nuclear Research and Training Center (SANAEM). The aim of this study is estimation of radon and progeny sourced effective dose for the people who are working at the spa facilities by measuring radon activity concentration (RAC) at the ambient air of indoor spa pools and dressing rooms. As it is known, the source of the radon gas is the radium content of the earth crust. Therefore, thermal waters coming from ground may contain dissolved radon and the radon can diffuse water to air. So the ambient air of spa pools can contain serious RAC that depends on a lot of parameters. In this regard, RAC measurements were executed at the 70 spa facilities in Turkey. The measurements were done with both active and passive methods at ambient air of spa pools and dressing rooms. Thus, active measurements were carried out by using the Alphaguard(®) with diffusion mode during half an hour, and passive measurements were carried out by using the humidity resistive CR-39 radon detectors during 2 months. Results show that RAC values at ambient air of spa pools varies between 13 Bq m(-3) and 10 kBq m(-3) Because long-term measurements are more reliable, if it is available, for dose calculations passive radon measurements (with CR-39 detectors) at ambient air of spa pools and dressing rooms were used, otherwise active measurement results were used. With the measurement by the conversion coefficients of ICRP 65 and occupational data of the employees has got from questionary forms, effective dose values were calculated. According to the calculations, spa employees are exposed to annual average dose between 0.05 and 29 mSv because of radon and progeny. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions

  15. 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.

  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. 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.

  18. 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).

  19. Determination of rain age via {gamma} rays from accreted radon progeny

    SciTech Connect

    Greenfield, M. B.; Ito, N.; Iwata, A.; Kubo, K.; Ishigaki, M.; Komura, K.

    2008-10-01

    The relative {gamma} ray activities from {sup 214}Pb and {sup 214}Bi condensed from precipitation are used to determine its 'age', the average time the accreted activity has been removed from secular equilibrium. A verifiable assumption that radon progeny on/in the surface/volume of droplets mostly remains in secular equilibrium until they begin their descent, enables estimates of their transit times to ground of typically a few tens of minutes. This agrees well with the time expected for the activity on the surface of droplets to reach the ground from heights of a few kilometers. The half lives of {gamma} activities from {sup 214}Bi and {sup 214}Pb, 19.7 and 26.9 min, respectively, are on the same scale as transit time to ground and close enough to each other to measure ratios of activities from secular equilibrium (1.00) to transient equilibrium (3.88) within a few hundreds of minutes. The ratio of {gamma} count rates is independent of knowledge of either initial activity or any systematic errors and thus limited only by the uncertainty from counting statistics, which from condensates of 5-30 l of rain viewed with 2{pi} solid angle by a 50% efficient, high-resolution Ge detector is only a few percent. These ratios fit extremely well to known theoretical curves, which cannot only be used to date rain but can also be extrapolated backward to determine radon progeny activities in rain prior to its descent, knowledge of which may facilitate further studies using radon progeny as tracers.

  20. 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.

  1. 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

  2. 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.

  3. 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.

  4. Quantitative Interpretation of Air Radon Progeny Fluctuations in Terms of Stability Conditions in the Atmospheric Boundary Layer

    NASA Astrophysics Data System (ADS)

    Salzano, Roberto; Pasini, Antonello; Casasanta, Giampietro; Cacciani, Marco; Perrino, Cinzia

    2016-09-01

    Determining the mixing height using a tracer can improve the information obtained using traditional techniques. Here we provide an improved box model based on radon progeny measurements, which considers the vertical entrainment of residual layers and the variability in the soil radon exhalation rate. The potential issues in using progeny instead of radon have been solved from both a theoretical and experimental perspective; furthermore, the instrumental efficiency and the counting scheme have been included in the model. The applicability range of the box model has been defined by comparing radon-derived estimates with sodar and lidar data. Three intervals have been analyzed ("near-stable", "transition" and "turbulent"), and different processes have been characterized. We describe a preliminary application case performed in Rome, Italy, while case studies will be required to determine the range limits that can be applied in any circumstances.

  5. 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

  6. "Deposition-flux to lung dose"--a new approach in radon inhalation dosimetry using wire-mesh capped direct radon progeny sensor.

    PubMed

    Rout, R P; Mishra, R; Sapra, B K; Mayya, Y S

    2014-12-01

    Assigning indoor radon doses to populations based on the widely used, cumulative radon concentration monitoring techniques is beset with errors arising due to uncertain equilibrium factors and unattached fractions. Moreover, the dose conversion factor (DCF) of radon decay products may vary by a factor of ∼40 within the particle size range from ∼0.5 nm to tens of micrometers. An ideal detector should have a response, which closely mimics the strong dependence of the DCF on the particle size. In this context, we propose a new approach in which the doses are computed directly from the time integrated progeny deposition fluxes on a suitably tailored surrogate surface. The deposition on this wire-mesh capped detector system closely mimics the deposition rate in human respiratory tract. The detection unit consists of an optimally designed wire-mesh capped Direct Radon Progeny Sensor (DRPS) system. Of the different wire-mesh types, 100 mesh types were found to be suitable considering the fine and coarse fraction penetration efficiencies. The calibration factor was theoretically derived as 0.0077 {mSv (Tracks cm(-2))(-1)}, for converting the measured atom flux in the 100-mesh capped DRPS system to inhalation dose attributed to radon progeny.

  7. 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.

  8. State-of-the-art instruments for measuring radon/thoron and their progeny in dwellings--a review.

    PubMed

    George, A C

    1996-04-01

    Radon and radon progeny measurements are conducted world-wide for the assessment of the radiation dose to workers and the general public. In the last 10 years, a variety of instruments have been developed that utilize different principles of detection for different measurement applications. The various instruments and methods used today depend on whether radon or radon/thoron progeny are being measured, the type of radiation being detected, and also the duration of the measurement. Other important design criteria are applicability, portability, convenience, reliability, and cost considerations. The instruments under consideration use the following detection systems: pulse ionization chambers, electret ionization chambers, scintillation detectors with zinc sulfide ZnS(Ag), alpha particle spectrometers with silicon diodes, surface barrier or diffused junction detectors, registration of nuclear tracks in solid-state materials, and gamma-ray spectometry with NaI(TI) scintillation crystals or germanium lithium (GeLi) semiconductors. Discussed in this paper are the advantages and disadvantages of the various portable instrumentation used for measuring radon, thoron, and their progeny. Also provided is guidance for their application in the field.

  9. Long-term measurements of radon, thoron and their airborne progeny in 25 schools in Republic of Srpska.

    PubMed

    Ćurguz, Z; Stojanovska, Z; Žunić, Z S; Kolarž, P; Ischikawa, T; Omori, Y; Mishra, R; Sapra, B K; Vaupotič, J; Ujić, P; Bossew, P

    2015-10-01

    This article reports results of the first investigations on indoor radon, thoron and their decay products concentration in 25 primary schools of Banja Luka, capital city of Republic Srpska. The measurements have been carried out in the period from May 2011 to April 2012 using 3 types of commercially available nuclear track detectors, named: long-term radon monitor (GAMMA 1)- for radon concentration measurements (C(Rn)); radon-thoron discriminative monitor (RADUET) for thoron concentration measurements (C(Tn)); while equilibrium equivalent radon concentration (EERC) and equilibrium equivalent thoron concentrations (EETC) measured by Direct Radon Progeny Sensors/Direct Thoron Progeny Sensors (DRPS/DTPS) were exposed in the period November 2011 to April 2012. In each school the detectors were deployed at 10 cm distance from the wall. The obtained geometric mean concentrations were C(Rn) = 99 Bq m(-3) and C(Tn) = 51 Bq m(-3) for radon and thoron gases respectively. Those for equilibrium equivalent radon concentration (EERC) and equilibrium equivalent thoron concentrations (EETC) were 11.2 Bq m(-3) and 0.4 Bq m(-3), respectively. The correlation analyses showed weak relation only between C(Rn) and C(Tn) as well as between C(Tn) and EETC. The influence of the school geographical locations and factors linked to buildings characteristic in relation to measured concentrations were tested. The geographical location and floor level significantly influence C(Rn) while C(Tn) depend only from building materials (ANOVA, p ≤ 0.05). The obtained geometric mean values of the equilibrium factors were 0.123 for radon and 0.008 for thoron. Copyright © 2015 Elsevier Ltd. All rights reserved.

  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. Fast determination of radon progeny concentrations. Report No. MRL 90-142(TR)

    SciTech Connect

    Bigu, J.; Edwardson, E.

    1990-01-01

    A technical evaluation of four Rn222 progeny measuring instruments (the Pylon WL-1000C, the MDA IWLM-811, the MIMIL IIM, and the EDA WLM-30) was conducted under laboratory controlled conditions and at several locations in an underground uranium mine. The laboratory evaluation consisted of a thorough study of the behaviour and performance of the instruments under a wide variety of environmental conditions, such as Rn222 gas concentration, Rn222 progeny concentration, temperature, relative humidity, aerosol concentration, and gamma-field exposure. The readings of the instruments were compared with the Thomas-Tsivoglou method, a widely accepted Rn222 progeny concentration measuring method. The instruments were rated according to accuracy, convenience of use, reliability, and ease of operation.

  16. Development and application of a complex numerical model and software for the computation of dose conversion factors for radon progenies.

    PubMed

    Farkas, Árpád; Balásházy, Imre

    2015-04-01

    A more exact determination of dose conversion factors associated with radon progeny inhalation was possible due to the advancements in epidemiological health risk estimates in the last years. The enhancement of computational power and the development of numerical techniques allow computing dose conversion factors with increasing reliability. The objective of this study was to develop an integrated model and software based on a self-developed airway deposition code, an own bronchial dosimetry model and the computational methods accepted by International Commission on Radiological Protection (ICRP) to calculate dose conversion coefficients for different exposure conditions. The model was tested by its application for exposure and breathing conditions characteristic of mines and homes. The dose conversion factors were 8 and 16 mSv WLM(-1) for homes and mines when applying a stochastic deposition model combined with the ICRP dosimetry model (named PM-A model), and 9 and 17 mSv WLM(-1) when applying the same deposition model combined with authors' bronchial dosimetry model and the ICRP bronchiolar and alveolar-interstitial dosimetry model (called PM-B model). User friendly software for the computation of dose conversion factors has also been developed. The software allows one to compute conversion factors for a large range of exposure and breathing parameters and to perform sensitivity analyses.

  17. Radon and radon progeny in 70 houses in the Tennessee Valley area: study design and measurement methods

    SciTech Connect

    Dudney, C.S.; Hawthorne, A.R.; Monar, K.P.; Quillen, J.L.; Clark, C. Jr.; Doane, R.W.; Wallace, R.G.; Reed, R.P.

    1986-01-01

    Levels of radon and its short-lived airborne progeny are being measured in a year-long study of 70 houses in four states in the Tennessee Valley. Various methods were used to solicit volunteers with differing degrees of success. Criteria for selection of houses in the study included presence of a lower level with cement floor and one or more block walls in contact with the soil, absence of obvious indications of technologically enhanced sources of radium, and proximity to one of four cities (Knoxville, Chattanooga, Birmingham, or Florence). By design, most houses in the study are in the same neighborhood as at least one other house in the study. Houses range in age from newly constructed to about 40 years old. Most of the houses have more than 2000 square feet of finished floor space. The lower level encompasses a garage in most cases. More complete information pertaining to house characteristics will be gathered in the course of the study. 19 refs., 1 fig.

  18. 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.

  19. 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.

  20. MEASUREMENT OF RADON, THORON AND THEIR PROGENY IN DIFFERENT TYPES OF DWELLING IN ALMORA DISTRICT OF KUMAUN HIMALAYAN REGION.

    PubMed

    Singh, Kuldeep; Semwal, Poonam; Pant, Preeti; Gusain, G S; Joshi, Manish; Sapra, B K; Ramola, R C

    2016-10-01

    The indoor concentrations of radon ((222)Rn), thoron ((220)Rn) and their daughter products were measured in the dwellings of Almora district in Kumaun Himalaya, India using pin-hole dosemeters and deposition progeny sensors. The measurements were made in the residential houses built of mud, stone with cement plaster and cemented house during winter season. Average [geometric mean (GM) values] radon and thoron concentrations for all dwellings were found to be 99.82 and 79.70 Bq m(-3), respectively, while average equilibrium equivalent radon concentration and equilibrium equivalent thoron concentration (measured for the first time for this region) were measured at 35.22 and 2.52 Bq m(-3), respectively. Radon concentration (GM values) was found to be 110.73, 97.00 and 93.85 Bq m(-3) for mud houses, stone with cemented plaster houses and cemented houses, respectively. On the other hand, thoron concentration values were 87.10, 75.79 and 75.68 Bq m(-3) for cemented houses, mud houses and stone with cemented plaster houses, respectively. Interpretations have been made on the basis of measured radon/thoron and progeny concentration values with respect to the difference of construction material of the dwellings. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  1. Doses from radon progeny as a source of external beta and gamma radiation.

    PubMed

    Markovic, V M; Krstic, D; Nikezic, D; Stevanovic, N

    2012-11-01

    Great deal of work has been devoted to determine doses from alpha particles emitted by (222)Rn and its progeny. In contrast, contribution of beta particles and following gamma radiation to total dose has mostly been neglected so far. The present work describes a study of the detriment of (222)Rn progeny for humans due to external exposure. Doses and dose conversion factors (DCFs) were determined for beta and gamma radiation in main organs and remainder tissue of the Oak Ridge National Laboratory phantom, taking into account (222)Rn progeny (214)Pb and (214)Bi distributed in the middle of a standard or typical room with dimensions 4 m × 5 m × 2.8 m. The DCF was found to be 7.37 μSv/WLM. Skin and muscle tissue from remainder tissue receives largest dose. Beta and gamma radiation doses from external exposure were compared with alpha, beta, and gamma doses from internal exposure where the source of radioactivity was the lungs. Total doses received in all main organs and remainder tissues were obtained by summing up the doses from external and internal exposure and the corresponding DCF was found to be 20.67 μSv/WLM.

  2. Evaluation of radon progeny from Mount St. Helens eruptions. Final report

    SciTech Connect

    Lepel, E.A.; Olsen, K.B.; Thomas, V.W.; Eichner, F.N.

    1982-09-01

    A network of twelve monitoring sites around Mount St. Helens was established to evaluate possible short-lived radioactivity in the fallen ash. Seven sites were located near major population centers of Washington and Oregon, and five sites were located within 80 km of the volcano. Each site monitored the radioactivity present by the use of thermoluminescent dosimeters which recorded the total exposure to radioactivity over the exposure period. Eruptions occurring on July 22, August 7, and October 16 to 18, 1980 were monitored. No statistically significant quantities of measurable radon daughters were observed.

  3. 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.

  4. 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.

  5. 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.

  6. A method of discriminating transuranic radionuclides from radon progeny using low-resolution alpha spectroscopy and curve-fitting techniques.

    PubMed

    Konzen, Kevin; Brey, Richard

    2012-05-01

    ²²²Rn (radon) and ²²⁰Rn (thoron) progeny are known to interfere with determining the presence of long-lived transuranic radionuclides, such as plutonium and americium, and require from several hours up to several days for conclusive results. Methods are proposed that should expedite the analysis of air samples for determining the amount of transuranic radionuclides present using low-resolution alpha spectroscopy systems available from typical alpha continuous air monitors (CAMs) with multi-channel analyzer (MCA) capabilities. An alpha spectra simulation program was developed in Microsoft Excel visual basic that employed the use of Monte Carlo numerical methods and serial-decay differential equations that resembled actual spectra. Transuranic radionuclides were able to be quantified with statistical certainty by applying peak fitting equations using the method of least squares. Initial favorable results were achieved when samples containing radon progeny were decayed 15 to 30 min, and samples containing both radon and thoron progeny were decayed at least 60 min. The effort indicates that timely decisions can be made when determining transuranic activity using available alpha CAMs with alpha spectroscopy capabilities for counting retrospective air samples if accompanied by analyses that consider the characteristics of serial decay.

  7. 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.

  8. 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.

  9. Radon progeny monitoring at the Eastern North Atlantic (ENA), Graciosa Island ARM facility and a potential earthquake precursory signal

    NASA Astrophysics Data System (ADS)

    Barbosa, Susana; Mendes, Virgilio B.; Azevedo, Eduardo B.

    2016-04-01

    Radon has been considered a promising earthquake precursor, the main rationale being an expected increase in radon exhalation in soil and rocks due to stress associated with the preparatory stages of an earthquake. However, the precursory nature of radon is far from being convincingly demonstrated so far. A major hindrance is the many meteorological and geophysical factors diving radon temporal variability, including the geophysical parameters influencing its emanation (grain size, moisture content, temperature), as well as the meteorological factors (atmospheric pressure, moisture, temperature, winds) influencing its mobility. Despite the challenges, radon remains one of the strongest candidates as a potential earthquake precursor, and it is of crucial importance to investigate the many factors driving its variability and its potential association with seismic events. Continuous monitoring of radon progeny is performed at the Eastern North Atlantic (ENA) facility located in the Graciosa island (Azores, 39N; 28W), a fixed site of the Atmospheric Radiation Measurement programme (ARM), established and supported by the Department of Energy (DOE) of the United States of America with the collaboration of the local government and University of the Azores. The Azores archipelago is associated with a complex geodynamic setting on the Azores triple junction where the American, Eurasian and African litospheric plates meet, resulting in significant seismic and volcanic activity. A considerable advantage of the monitoring site is the availability of a comprehensive dataset of concurrent meteorological observations performed at the ENA facility and freely available from the ARM data archive, enabling a detailed analysis of the environmental factors influencing the temporal variability of radon's progeny. Gamma radiation is being measured continuously every 15 minutes since May 2015. The time series of gamma radiation counts is dominated by sharp peaks lasting a few hours and

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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

  15. 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.

  16. 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)

  17. 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.

  18. 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.

  19. 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.

  20. 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

  1. 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).

  2. 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.

  3. 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.

  4. Variation of short-lived beta radionuclide (radon progeny) concentrations and the mixing processes in the atmospheric boundary layer.

    PubMed

    Veleva, B; Valkov, N; Batchvarova, E; Kolarova, M

    2010-07-01

    Radon is emitted to the atmosphere with quasi constant emission rates depending on the radium concentration in the earth's crust and soil physical properties. In this way, the 222Rn and 220Rn concentration in air reflects significantly the thickness of the atmospheric boundary layer (ABL). The aerosol-associated, beta-emitting progeny nuclides of 222Rn were measured daily in the framework of the atmospheric radioactivity monitoring program of NIMH at Sofia. The 214Pb concentration was estimated from the measured short-lived beta activity of 24-h filter samples, changed daily at 6:00 GMT. The impact of some meteorological factors such as wind direction, wind velocity, humidity, and temperature on short-lived beta radionuclides is estimated, and the results show no simple statistical relationship. A seasonal pattern was observed with winter minima and late summer-early autumn maxima. High variability in daily morning concentrations and mean monthly values was observed. There were well pronounced differences between years. The height of the convective ABL was estimated from daily radio-soundings at 12:00 GMT for the period 2001-2006 and from seven soundings per day during the experimental campaign in Sofia in October 2003. In general, concentrations of short-lived 222Rn progeny nuclides decreased with increased convective ABL height. 2009 Elsevier Ltd. All rights reserved.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. An automated, semi-continuous system for measuring indoor radon progeny activity-weighted size distributions, d sub p : 0. 5--500 nm

    SciTech Connect

    Li, Chih-Shan; Hopke, P.K.; Ramamurthi, M.

    1990-05-01

    A system for the detection and measurement of indoor radon progeny activity-weighted size distributions (particle size, d{sub p} > 0.5 nm) and concentration levels has been developed. The system is microcomputer-controlled and involves a combination of multiple wire screen (Graded Screen Array) sampler-detector units operated in parallel. The radioactivity sampled in these units permits the estimation of the radon progeny activity-weighted size distributions and concentration levels on a semi-continuous basis. This paper presents details of the system and describes various stages in the development of the system. Results of field measurements in a residential environment are presented to illustrate the resolution, sensitivity and capabilities of the measurement system. 16 refs., 4 figs., 1 tab.

  10. 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.

  11. 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%.

  12. 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%.

  13. 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.

  14. 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, ...

  15. 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 ...

  16. 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.)

  17. 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.

  18. 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 ...

  19. 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

  20. 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.

  1. 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.

  2. 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.

  3. Characterization of Radon Progeny in EXO-200 Using Machine Learning Algorithms

    NASA Astrophysics Data System (ADS)

    Smith, Erica

    Neutrinoless double beta decay (0nubetabeta) is a rare, second-order process that occurs in certain isotopes for which beta decay is energetically forbidden. EXO-200 is a 0nubetabeta experiment with 110 kg of active liquid xenon (LXe) isotopically enriched in 136Xe. EXO-200 detects events using a combination of scintillation and ionization signals, which allows for excellent particle discrimination. However, events with a low ionization signal cannot be fully characterized with the current analysis framework. To fill in these gaps, we introduce a boosted decision tree regressor as a new tool to characterize events in the detector. We focus on alpha decays of 222Rn and its progeny, which have low ionization signals that often fall below the threshold for position reconstruction. Using information gained from this technique, we confirm previous results for the 218Po ion velocity and improve previous results for the 218Po ionization fraction. We also investigate events that occur near the walls of the vessel. These events have no ionization signal and therefore cannot be characterized with any existing technique in the analysis framework. By investigating these events we determine that they are not distributed uniformly throughout the detector, which may point to charging up of the plastics inside the LXe vessel or a "hot spot'' on the plastic due to contamination during cleaning and installation.

  4. 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…

  5. 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…

  6. 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

  7. 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

  8. 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.

  9. 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

  10. 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

  11. 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.

  12. 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.

  13. Neurobehavioral Effects of Sodium Tungstate Exposure on Rats and Their Progeny

    DTIC Science & Technology

    2007-06-30

    Neurobehavioral Effects of Sodium Tungstate Expo sure on Rats and Their Progeny S.M. McInturf ALYNV. Bekkedal A. Olabisi D. Arfsten E. Wilfong IL...20071116226 Neurobehavioral Effects of Sodium Tungstate Exposure on Rats and. Their Progeny S.M. McInturf M.Y.V. Bekkedal A. Olabisi D. Arfsten E...days of daily tungsten exposure via drinking water. Sprague-Dawley rats were orally dosed with diH20 vehicle, 5 or 125 mg/kg/day of sodium tungstate for

  14. 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

  15. 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

  16. 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.

  17. 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

  18. 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.

  19. Coagulation effect on the activity size distributions of long lived radon progeny aerosols and its application to atmospheric residence time estimation techniques.

    PubMed

    Anand, S; Mayya, Y S

    2015-03-01

    The long lived naturally occurring radon progeny species in the atmosphere, namely (210)Pb, (210)Bi and (210)Po, have been used as important tracers for understanding the atmospheric mixing processes and estimating aerosol residence times. Several observations in the past have shown that the activity size distribution of these species peaks at larger particle sizes as compared to the short lived radon progeny species - an effect that has been attributed to the process of coagulation of the background aerosols to which they are attached. To address this issue, a mathematical equation is derived for the activity-size distribution of tracer species by formulating a generalized distribution function for the number of tracer atoms present in coagulating background particles in the presence of radioactive decay and removal. A set of these equations is numerically solved for the progeny chain using Fuchs coagulation kernel combined with a realistic steady-state aerosol size spectrum that includes nucleation, accumulation and coarse mode components. The important findings are: (i) larger shifts in the modal sizes of (210)Pb and (210)Po at higher aerosol concentrations such as that found in certain Asian urban regions (ii) enrichment of tracer specific activity on particles as compared to that predicted by pure attachment laws (iii) sharp decline of daughter-to-parent activity ratios for decreasing particle sizes. The implication of the results to size-fractionated residence time estimation techniques is highlighted. A coagulation corrected graphical approach is presented for estimating the residence times from the size-segregated activity ratios of (210)Bi and (210)Po with respect to (210)Pb. The discrepancy between the residence times predicted by conventional formula and the coagulation corrected approach for specified activity ratios increases at higher atmospheric aerosol number concentrations (>10(10) #/m(3)) for smaller sizes (<1 μm). The results are further

  20. 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.

  1. Perinatal ciclosporin A exposure elicits sex-related cardiac dysfunction and inflammation in the rat progeny.

    PubMed

    El-Bassossy, Hany M; Awan, Zuhier; El-Mas, Mahmoud M

    2017-09-05

    Ciclosporin A (CSA) has been identified with harmful cardiotoxicity but little, if any, is known about the influence of perinatal exposure upon the cardiac function of the progeny. The present work examines the premise that perinatal contact with CSA undermines the cardiac function of sexually mature rats. Administration of CSA (15mg/kg/day sc) to pregnant rats from day 6 of conception till weaning led to a decrease in gradient of the end-systolic pressure-volume relationship by a factor of ten for male progeny and a factor of two for female progeny. Perinatally CSA-exposed male, but not female, progeny also demonstrated significantly increased systolic and diastolic blood pressure, along with significantly increased JT interval and a tendency towards increased QTc interval, indicating delayed left ventricular (LV) repolarization and perhaps arrhythmogenesis. Conversely, female, but not male, progeny exposed perinatally to CSA showed a delay in atrioventricular (AV) conduction, as demonstrated by significantly prolonged P duration and a tendency towards increased PR interval. CSA increased serum tumor necrosis factor α (TNFα) and decreased serum adiponectin levels and cardiac adiponectin receptor expression in male progeny, in contrast to no effects in female progeny. Signs of improved oxidative state (decreased 8-isoprostane and increased catalase activity) appeared only in CSA-exposed female rats. Moreover, cardiac muscle degeneration and pyknosis was more observed in male than in female rats. In brief, the sex plays a key role in determining the extent of the deterioration in functional and inflammatory states of the heart that follow perinatal CSA exposure in rats. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. 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

  3. 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.

  4. 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

  5. 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.

  6. Daily variation of radon gas and its short-lived progeny concentration near ground level and estimation of aerosol residence time

    NASA Astrophysics Data System (ADS)

    M, Mohery; A, M. Abdallah; A, Ali; S, S. Baz

    2016-05-01

    Atmospheric concentrations of radon (222Rn) gas and its short-lived progenies 218Po, 214Pb, and 214Po were continuously monitored every four hours at the ground level in Jeddah city, Kingdom of Saudi Arabia. The measurements were performed three times every week, starting from November 2014 to October 2015. A method of electrostatic precipitation of positively charged 218Po and 214Po by a positive voltage was applied for determining 222Rn gas concentration. The short-lived 222Rn progeny concentration was determined by using a filter holder connected with the alpha-spectrometric technique. The meteorological parameters (relative air humidity, air temperature, and wind speed) were determined during the measurements of 222Rn and its progeny concentrations. 222Rn gas as well as its short-lived progeny concentration display a daily and seasonal variation with high values in the night and early morning hours as compared to low values at noon and in the afternoon. The observed monthly atmospheric concentrations showed a seasonal trend with the highest values in the autumn/winter season and the lowest values in the spring/summer season. Moreover, and in parallel with alpha-spectrometric measurements, a single filter-holder was used to collect air samples. The deposited activities of 214Pb and the long-lived 222Rn daughter 210Pb on the filter were measured with the gamma spectrometric technique. The measured activity concentrations of 214Pb by both techniques were found to be relatively equal largely. The highest mean seasonally activity concentrations of 210Pb were observed in the autumn/winter season while the lowest mean were observed in the spring/summer season. The mean residence time (MRT) of aerosol particles in the atmospheric air could be estimated from the activity ratios of 210Pb/214Pb. Project supported by the Deanship of Scientific Research (DSR), King Abdulaziz University, Jeddah (Grant No. 291/965/1434).

  7. 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.

  8. 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.

  9. 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

  10. 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

  11. 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

  12. 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.

  13. Investigation of radon, thoron, and their progeny near the earth`s surface. Final report, 1 January 1994--31 December 1997

    SciTech Connect

    Schery, S.D.; Wasiolek, P.T.

    1998-01-01

    This is the final report for DOE Grant DE-FG03-94ER6178, covering a performance period of 1 January 1994 through 31 December 1997. The DOE award amount for this period was $547,495. The objective of the project as stated in its proposal was {open_quotes}to improve our understanding of the physical processes controlling the concentration of radon, thoron, and their progeny in the atmospheric environment.{close_quotes} The original project was directed at developing underlying science that would help with evaluation of the health hazard from indoor radon in the United States and implementation of corrective measures that might be employed to reduce the health hazard. As priorities within the Office of Health and Environment (OHER) changed, and the radon research program was phased out, emphasis of the project was shifted somewhat to be also relevant to other interests of the OHER, namely global pollution and climate change and pollution resulting from energy production. This final report is brief, since by reference it can direct the reader to the comprehensive research publications that have been generated by the project. In section 2, we summarize the main accomplishments of the project and reference the primary publications. There were seven students who received support from the project and their names are listed in section 3. One of these students (Fred Yarger, Ph.D. candidate) continues to work on research initiated through this project. No post-docs received support from the project, although one of the co-principal investigators (Dr. Piotr Wasiolek) received the majority of his salary from the project. The project also provided part-time support for a laboratory manager (Dr. Maryla Wasiolek). Section 4 lists chronologically the reports and publications resulting from the project (references 1 through 12), and the Appendix provides abstracts of major publications and reports.

  14. 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

  15. 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.

  16. 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.

  17. Reduction of radon progeny concentration by means of an air cleaner. Report no. MRL 90-143(TR)

    SciTech Connect

    Bigu, J.; Edwardson, E.

    1990-01-01

    There are a variety of airborne radionuclides found in working and living environments which at sufficiently elevated concentration levels can pose a potential hazard to human health. This report describes the use of a device which operates on a 'hybrid' technique consisting of air filtration, electrostatic deposition, and turbulent air mixing to reduce the concentration levels of Rn222 progeny levels in air. Experiments were carried out in Rn222/Rn222 progeny atmospheres when the air cleaner was operating and when it was turned off.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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...

  3. 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...

  4. 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

  5. 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.

  6. 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

  7. 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.

  8. 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.

  9. The influence of particle size distribution on dose conversion factors for radon progeny in the underground excavations of hard coal mine.

    PubMed

    Skubacz, Krystian; Wojtecki, Łukasz; Urban, Paweł

    2016-10-01

    In Polish underground mines, hazards caused by enhanced natural radioactivity occur. The sources of radiation exposure are short-lived radon decay products, mine waters containing radium (226)Ra and (228)Ra and the radioactive sediments that can precipitate out of these waters. For miners, the greatest exposure is usually due to short-lived radon decay products. The risk assessment is based on the measurement of the total potential alpha energy concentration (PAEC) and the evaluation of the related dose by using the dose conversion factor as recommended by relevant legal requirements. This paper presents the results of measurements of particle size distributions of ambient aerosols in an underground hard coal mine, the assessment of the radioactive particle size distribution of the short-lived radon decay products and the corresponding values of dose conversion factors. The measurements of the ambient airborne particle size distribution were performed in the range from a few nanometers to about 20 μm. The study therefore included practically the whole class of respirable particles. The results showed that the high concentration of ultrafine and fine aerosols measured can significantly affect the value of the dose conversion factors, and consequently the corresponding committed effective dose, to which the miners can be exposed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Cigarette use and the estimation of lung cancer attributable to radon in the United States

    SciTech Connect

    Lubin, J.H.; Steindorf, K. |

    1995-01-01

    Residential exposure to radioactive radon and its decay products has been estimated to account for 10-12% of all lung cancer deaths in the US. It has been difficult to evaluate fully the impact of cigarette smoking, the most important cause of lung cancer, on this estimate, because factors for patterns of tobacco use have not been included in the risk models, since risk models are derived from studies of underground miners exposed to radon and detailed data on smoking are limited. Lung cancer risk estimates for exposure to radon progeny in smoker and non-smoker populations are obtained by applying the same risk model to each population group, thereby assuming the joint effects of smoking and exposure to radon progeny are multiplicative. However, in miners, joint relative risks (RR) for the two exposures are most consistent with an intermediate relationship between multiplicative and additive, so that the present approach likely results in an overestimate of risk in smokers and an underestimate of risk in nonsmokers. One approach for adjusting risk models to incorporate smoking status is based on the relative magnitude of the effects of radon progeny in smokers and nonsmokers and therefore may not be applicable to non-miner populations if the proportion of smokers and the RR for smoking differ. We show that the modification can be derived explicitly by assuming an arithmetic mixture model for the joint RR for smoking and exposure to radon progeny. In this way, smoking parameters in the population of interest (the proportion of smokers and the RR of smoking) can be used directly to adjust radon progeny risk models and obtain risk estimates that are specific for smokers and nonsmokers. With an intermediate RR relationship for smoking and radon progeny, the attributable percentage of lung cancer deaths from residential radon may be twofold greater in nonsmokers than in smokers. 20 refs., 1 fig., 3 tabs.

  11. 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.

  12. 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

  13. 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.

  14. Analysis of alpha particles spectra of the Radon and Thoron progenies generated by an electrostatic collection detector using new software.

    PubMed

    Sabbarese, C; Ambrosino, F; Buompane, R; Pugliese, M; Roca, V

    2017-04-01

    A complete and detailed analysis of alpha spectra from the (222)Rn and (220)Rn progenies was performed by newly developed software. The software identifies the alpha peaks, performs appropriate fits and calculates the net area and its uncertainty, considering the entire background. The deconvolution of the overlapped peaks of (218)Po and (212)Bi allows us also to evaluate their minimum detectable area. The efficiency of the electrostatic detection method was recalculated and new useful considerations on the collected alpha emitters were made.

  15. 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.

  16. 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.

  17. 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

  18. 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)

  19. 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)

  20. 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)

  1. 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)

  2. 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.

  3. 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

  4. 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

  5. Levels of thoron and progeny in high background radiation area of southeastern coast of Odisha, India.

    PubMed

    Ramola, R C; Gusain, G S; Rautela, B S; Sagar, D V; Prasad, G; Shahoo, S K; Ishikawa, T; Omori, Y; Janik, M; Sorimachi, A; Tokonami, S

    2012-11-01

    Exposure to radon, (222)Rn, is assumed to be the most significant source of natural radiation to human beings in most cases. It is thought that radon and its progeny are major factors that cause cancer. The presence of thoron, (220)Rn, was often neglected because it was considered that the quantity of thoron in the environment is less than that of radon. However, recent studies have shown that a high thoron concentration was found in some regions and the exposure to (220)Rn and its progeny can equal or several time exceed that of (220)Rn and its progeny. The results of thoron and its progeny measurements in the houses of high background radiation area (HBRA) of the southeastern coast of Odisha, India presented here. This area is one of the high background radiation areas in India with a large deposit of monazite sand which is the probable source of thoron. Both active and passive methods were employed for the measurement of thoron and its progeny in cement, brick and mud houses in the study area. Thoron concentration was measured using RAD-7 and Raduet. A CR-39 track detector was employed for the measurement of environmental thoron progeny, both in active and passive modes. Thoron and its progeny concentrations were found to be comparatively high in the area. A comparison between the results obtained with various techniques is presented in this paper.

  6. 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.

  7. Maternal-engineered nanomaterial exposure disrupts progeny cardiac function and bioenergetics.

    PubMed

    Hathaway, Quincy A; Nichols, Cody E; Shepherd, Danielle L; Stapleton, Phoebe A; McLaughlin, Sarah L; Stricker, Janelle C; Rellick, Stephanie L; Pinti, Mark V; Abukabda, Alaeddin B; McBride, Carroll R; Yi, Jinghai; Stine, Seth M; Nurkiewicz, Timothy R; Hollander, John M

    2017-03-01

    Nanomaterial production is expanding as new industrial and consumer applications are introduced. Nevertheless, the impacts of exposure to these compounds are not fully realized. The present study was designed to determine whether gestational nano-sized titanium dioxide exposure impacts cardiac and metabolic function of developing progeny. Pregnant Sprague-Dawley rats were exposed to nano-aerosols (~10 mg/m(3), 130- to 150-nm count median aerodynamic diameter) for 7-8 nonconsecutive days, beginning at gestational day 5-6 Physiological and bioenergetic effects on heart function and cardiomyocytes across three time points, fetal (gestational day 20), neonatal (4-10 days), and young adult (6-12 wk), were evaluated. Functional analysis utilizing echocardiography, speckle-tracking based strain, and cardiomyocyte contractility, coupled with mitochondrial energetics, revealed effects of nano-exposure. Maternal exposed progeny demonstrated a decrease in E- and A-wave velocities, with a 15% higher E-to-A ratio than controls. Myocytes isolated from exposed animals exhibited ~30% decrease in total contractility, departure velocity, and area of contraction. Bioenergetic analysis revealed a significant increase in proton leak across all ages, accompanied by decreases in metabolic function, including basal respiration, maximal respiration, and spare capacity. Finally, electron transport chain complex I and IV activities were negatively impacted in the exposed group, which may be linked to a metabolic shift. Molecular data suggest that an increase in fatty acid metabolism, uncoupling, and cellular stress proteins may be associated with functional deficits of the heart. In conclusion, gestational nano-exposure significantly impairs the functional capabilities of the heart through cardiomyocyte impairment, which is associated with mitochondrial dysfunction.NEW & NOTEWORTHY Cardiac function is evaluated, for the first time, in progeny following maternal nanomaterial inhalation. The

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. 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...

  15. 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.

  16. 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...

  17. 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

  18. 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.

  19. 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.

  20. 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

  1. A generic biokinetic model for noble gases with application to radon

    SciTech Connect

    Leggett, Richard Wayne; Marsh, James; Gregoratto, Demetrio; Blanchardon, Eric

    2013-01-01

    The International Commission for Radiological Protection (ICRP) currently uses a dose conversion coefficient to calculate effective dose per unit exposure to radon and its progeny. The coefficient is derived by dividing the detriment associated with unit exposure to radon, as estimated from epidemiological studies, by the detriment per unit effective dose, as estimated mainly from atomic bomb survivor data and animal studies. In a recent statement the ICRP indicated that future guidance on exposure to radon and its progeny will be developed in the same way as guidance for any other radionuclide. That is, intake of radon and progeny will be limited on the basis of effective dose coefficients derived from biokinetic and dosimetric models. This paper proposes a biokinetic model for systemic (absorbed) radon for use in the calculation of dose coefficients for inhaled or ingested radon. The model is based largely on physical laws governing transfer of a non-reactive and soluble gas between materials. Model predictions are shown to be consistent with results of controlled studies of the fate of internally deposited radon in human subjects.

  2. 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.

  3. Thoron and thoron progeny measurements in German clay houses.

    PubMed

    Gierl, S; Meisenberg, O; Feistenauer, P; Tschiersch, J

    2014-07-01

    In recent years, elevated thoron concentrations were found in houses built of unfired clay. In this study experiments were carried out in 17 traditional and modern clay houses in Germany to obtain an overview of indoor thoron in such houses. Long-term measurements over an 8-week period were performed using a newly developed Unattended Battery-Operated Progeny Measurement Device (UBPM) for measuring thoron progeny. This instrument uses a high-voltage electric field to precipitate radon and thoron progeny on nuclear track detectors. Additional active and passive measurements of radon, thoron and their progeny were performed. The equilibrium equivalent thoron concentration was found to be between 2 and 10 Bq m(-3). Gas concentrations were found to be between 20 and 160 Bq m(-3) for radon and between 10 and 90 Bq m(-3) for thoron 20 cm from the wall. The thoron exposure contributes significantly to the inhalation dose of the dwellers (0.6-4 mSv a(-1)).

  4. Maternal nicotine exposure during lactation alters hypothalamic neuropeptides expression in the adult rat progeny.

    PubMed

    Younes-Rapozo, Viviane; Moura, Egberto G; Manhães, Alex C; Pinheiro, Cintia R; Santos-Silva, Ana Paula; de Oliveira, Elaine; Lisboa, Patricia C

    2013-08-01

    Maternal exposure to nicotine during lactation causes hyperleptinemia in the pups and, at adulthood, these animals are overweight and hyperleptinemic, while, in their hypothalamus, the leptin signaling pathway is reduced, evidencing a central leptin resistance. Then, we evaluated the expression of pro-opiomelanocortin (POMC), alpha-melanocyte stimulating hormone (α-MSH), cocaine and amphetamine-regulated transcript (CART), neuropeptide Y (NPY), agouti-related peptide (AgRP) and others in different hypothalamic nuclei in order to better understand the mechanisms underlying the obese phenotype observed in these animals at adulthood. On the 2nd postnatal day (P2), dams were subcutaneously implanted with osmotic minipumps releasing nicotine (NIC-6 mg/kg/day) or saline for 14 days. Offspring were killed in P180 and immunohistochemistry and Western blot analysis were carried out. Significance data had p<0.05. Adult NIC offspring showed more intense NPY staining in the paraventricular nucleus (PVN) (+21%) and increased number of POMC-positive cells in the: arcuate nucleus (+33%), as an increase in fiber density of α-MSH in PVN (+85%). However, the number of CART-positive cells was reduced in the PVN (-25%). CRH staining was more intense in NIC offspring (+136%). Orexins and AgRP were not altered. Thus, maternal nicotine exposure changes hypothalamic neuropeptides in the adult progeny that is partially compatible with leptin resistance.

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. 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.

  11. 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)

  12. 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)

  13. 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

  14. Hypoxia Treatment of Callosobruchus maculatus Females and Its Effects on Reproductive Output and Development of Progeny Following Exposure

    PubMed Central

    Yan, Yan; Williams, Scott B.; Baributsa, Dieudonne; Murdock, Larry L.

    2016-01-01

    Modified atmospheres present a residue-free alternative to fumigants for controlling postharvest pests of grain during storage. How sub-lethal applications of this method affects the reproductive fitness of target pests, however, is still not fully understood. We examined how low levels of ambient oxygen influence the reproduction of the female cowpea bruchid (Callosobruchus maculatus), a pest of cowpea. We used three low-oxygen atmospheres—2%, 5% and 10% (v/v) oxygen—and observed their effects on: (1) the number of eggs laid by bruchids compared to insects held in normoxic (~20% oxygen) conditions; (2) the total number of eggs laid; and (3) the number of progeny that reached maturity. Low oxygen did not significantly affect the number of eggs laid during 48 or 72 h of exposure, but 2% and 5% oxygen did negatively affected total egg production. Increasing the exposure time from 48 to 72 h further depressed lifetime reproductive output. Maternal and egg exposure to hypoxia reduced the number of progeny that reached adulthood. Lower adult emergence was observed from eggs laid under low oxygen and longer exposure times. These data demonstrate that hermetic conditions depress the egg-laying behavior of cowpea bruchids and the successful development of their progeny. PMID:27322332

  15. Hypoxia Treatment of Callosobruchus maculatus Females and Its Effects on Reproductive Output and Development of Progeny Following Exposure.

    PubMed

    Yan, Yan; Williams, Scott B; Baributsa, Dieudonne; Murdock, Larry L

    2016-06-17

    Modified atmospheres present a residue-free alternative to fumigants for controlling postharvest pests of grain during storage. How sub-lethal applications of this method affects the reproductive fitness of target pests, however, is still not fully understood. We examined how low levels of ambient oxygen influence the reproduction of the female cowpea bruchid (Callosobruchus maculatus), a pest of cowpea. We used three low-oxygen atmospheres-2%, 5% and 10% (v/v) oxygen-and observed their effects on: (1) the number of eggs laid by bruchids compared to insects held in normoxic (~20% oxygen) conditions; (2) the total number of eggs laid; and (3) the number of progeny that reached maturity. Low oxygen did not significantly affect the number of eggs laid during 48 or 72 h of exposure, but 2% and 5% oxygen did negatively affected total egg production. Increasing the exposure time from 48 to 72 h further depressed lifetime reproductive output. Maternal and egg exposure to hypoxia reduced the number of progeny that reached adulthood. Lower adult emergence was observed from eggs laid under low oxygen and longer exposure times. These data demonstrate that hermetic conditions depress the egg-laying behavior of cowpea bruchids and the successful development of their progeny.

  16. 76 FR 72006 - Draft Interim Staff Guidance: Evaluations of Uranium Recovery Facility Surveys of Radon and Radon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-21

    ... COMMISSION Draft Interim Staff Guidance: Evaluations of Uranium Recovery Facility Surveys of Radon and Radon... Recovery Facility Surveys of Radon and Radon Progeny in Air and Demonstrations of Compliance with 10 CFR 20... that existing guidance does not sufficiently detail how the NRC staff reviews surveys of radon and...

  17. 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.

  18. 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.

  19. 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.

  20. Oral exposure of broiler breeder hens to extra thyroxine modulates early adaptive immune responses in progeny chicks.

    PubMed

    Akhlaghi, A; Zamiri, M J; Jafari Ahangari, Y; Atashi, H; Ansari Pirsaraei, Z; Deldar, H; Eghbalian, A N; Akhlaghi, A A; Navidshad, B; Yussefi Kelarikolaei, K; Hashemi, S R

    2013-04-01

    Based on the findings of a recent study suggesting a decreased cold-induced ascites incidence in broiler progeny from hyperthyroid (HYPER) breeder hens, and a controversy on the effects of hyperthyroidism on immunocompetence, the present study was conducted to determine the probable adverse effect of induced maternal hyperthyroidism on immune function in progeny chicks. Breeder hens (n = 88) were randomly allotted to the control or HYPER groups and received common or thyroxine (T4)-added (1 mg/L) water, respectively. The hens were artificially inseminated, and hatching eggs (n = 924) were incubated. Thereafter, the male hatchlings (n = 288) were reared for 42 d, and several cellular and humoral immune responses were evaluated at standard or low ambient temperature. Prevaccination antibody titers to Newcastle disease, infectious bronchitis, and infectious bursal disease virus were higher in HYPER chicks during 1 wk of age, although not different in their dams. For primary response to SRBC administered at 7 d of age, HYPER chicks recorded higher total, IgM (d 14), and IgG (d 21) anti-SRBC antibody titers. Higher cutaneous basophilic hypersensitivity response in HYPER chicks (d 10) was not observed at 35 d of age. Carbon clearance assay showed no difference, but in vitro lymphoproliferative response to concanavalin A was higher in 19-d-old HYPER chicks, independent of temperature treatment. An increase in lymphocyte percentage coincided with a decreased heterophil percentage and heterophil to lymphocyte ratio (d 14) in the HYPER group. The weight of lymphoid organs in progeny was not influenced by the oral exposure of dams to extra T4. Independent of T4 treatment, cold exposure was generally associated with decreased immune functions at early stages. The data suggested that oral exposure of broiler breeder hens to 1 mg/L of T4 not only had no adverse effect on immune function, but also modulated early adaptive immune responses in progeny chicks for which the causal

  1. 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

  2. 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.

  3. 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.

  4. 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, ...

  5. 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 ...

  6. Evaluation of the intake of radon through skin from thermal water.

    PubMed

    Sakoda, Akihiro; Ishimori, Yuu; Tschiersch, Jochen

    2016-07-01

    The biokinetics of radon in the body has previously been studied with the assumption that its absorption through the skin is negligibly small. This assumption would be acceptable except in specific situations, such as bathing in a radon hot spring where the radon concentration in thermal water is far higher than that in air. The present study focused on such a situation in order to better understand the biokinetics of radon. To mathematically express the entry of radon through the skin into the body, we first modified the latest sophisticated biokinetic model for noble gases. Values of an important parameter for the model-the skin permeability coefficient K (m s(-1))-were derived using data from previous human studies. The analysis of such empirical data, which corresponded to radon concentrations in the air exhaled by subjects during and following bathing in radon-rich thermal water, revealed that the estimated K values had a log-normal distribution. The validity of the K values and the characteristics of the present model are then discussed. Furthermore, the impact of the intake of radon or its progeny via inhalation or skin absorption on radiation dose was also assessed for possible exposure scenarios in a radon hot spring. It was concluded that, depending on the radon concentration in thermal water, there might be situations in which the dose contribution resulting from skin absorption of radon is comparable to that resulting from inhalation of radon and its progeny. This conclusion can also apply to other therapeutic situations (e.g. staying in the pool for a longer period). © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

  7. Evaluation of the intake of radon through skin from thermal water

    PubMed Central

    Sakoda, Akihiro; Ishimori, Yuu; Tschiersch, Jochen

    2016-01-01

    The biokinetics of radon in the body has previously been studied with the assumption that its absorption through the skin is negligibly small. This assumption would be acceptable except in specific situations, such as bathing in a radon hot spring where the radon concentration in thermal water is far higher than that in air. The present study focused on such a situation in order to better understand the biokinetics of radon. To mathematically express the entry of radon through the skin into the body, we first modified the latest sophisticated biokinetic model for noble gases. Values of an important parameter for the model—the skin permeability coefficient K (m s−1)—were derived using data from previous human studies. The analysis of such empirical data, which corresponded to radon concentrations in the air exhaled by subjects during and following bathing in radon-rich thermal water, revealed that the estimated K values had a log-normal distribution. The validity of the K values and the characteristics of the present model are then discussed. Furthermore, the impact of the intake of radon or its progeny via inhalation or skin absorption on radiation dose was also assessed for possible exposure scenarios in a radon hot spring. It was concluded that, depending on the radon concentration in thermal water, there might be situations in which the dose contribution resulting from skin absorption of radon is comparable to that resulting from inhalation of radon and its progeny. This conclusion can also apply to other therapeutic situations (e.g. staying in the pool for a longer period). PMID:26983980

  8. 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.

  9. 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

  10. 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

  11. 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.

  12. 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.

  13. 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

  14. Comparative dosimetry of radon in mines and homes. Panel of dosimetric assumptions affecting the application of radon risk estimates, Board on Radiation Effects Research, Commission on Life Sciences, National Research Council

    SciTech Connect

    Not Available

    1991-01-01

    The National Academy study addresses a topic of widespread attention since the discovery in 1984 of a worker found to be contaminated with radon in his home. Scientists have long understood the dangers of exposure to radon and its progeny and have analyzed the effects of exposure of these radionuclides in underground miner populations. However, extensive analyses on effects of radon exposure in the home are only now being performed. This study evaluates available data, describes uncertainties and attempts to translate dosimetric information related mine worker exposure to risk information regarding home radon exposures. The Academy's compilation and evaluation of the data are, as usual, pain-staking and thorough. Their discussions of uncertainties is helpful and careful to describe the boundaries and limitations of their results. The dosimetric model which resulted from their comparative evaluation is clearly presented. Risk assessors concerned about residential exposures to radionuclides will find this study useful.

  15. 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

  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. 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.

  18. 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.

  19. 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.

  20. 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

  1. Radiation doses to individuals due to ²³⁸U, ²³²Th and ²²²Rn from the immersion in thermal waters and to radon progeny from the inhalation of air inside thermal stations.

    PubMed

    Misdaq, M A; Ghilane, M; Ouguidi, J; Outeqablit, K

    2012-11-01

    In Morocco, thermal waters have been used for decades for the treatment of various diseases. To explore the exposure pathway of (238)U, (232)Th and (222)Rn to the skin of bathers from the immersion in thermal waters, these radionuclides were measured inside waters collected from different Moroccan thermal springs, by means of CR-39 and LR-115 type II solid-state nuclear track detectors (SSNTDs), and corresponding annual committed effective doses to skin were determined. Accordingly, to assess radiation dose due to radon short-lived decay products from the inhalation of air by individuals, concentrations of these radionuclides were measured in indoor air of two thermal stations by evaluating mean critical angles of etching of the CR-39 and LR-115 II SSNTDs. Committed effective doses due to the short-lived radon decay products (218)Po and (214)Po by bathers and working personnel inside the thermal stations studied were determined.

  2. 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.

  3. Radon dose assessment in underground mines in Brazil.

    PubMed

    Santos, T O; Rocha, Z; Cruz, P; Gouvea, V A; Siqueira, J B; Oliveira, A H

    2014-07-01

    Underground miners are internally exposed to radon, thoron and their short-lived decay products during the mineral processing. There is also an external exposure due to the gamma emitters present in the rock and dust of the mine. However, the short-lived radon decay products are recognised as the main radiation health risk. When inhaled, they are deposited in the respiratory system and may cause lung cancer. To address this concern, concentration measurements of radon and its progeny were performed, the equilibrium factor was determined and the effective dose received was estimated in six Brazilian underground mines. The radon concentration was measured by using E-PERM, AlphaGUARD and CR-39 detectors. The radon progeny was determined by using DOSEman. The annual effective dose for the miners was estimated according to United Nations Scientific Committee on the Effects of Atomic Radiation methodologies. The mean value of the equilibrium factor was 0.4. The workers' estimated effective dose ranged from 1 to 21 mSv a(-1) (mean 9 mSv a(-1)). © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Zebrafish exposure to environmentally relevant concentration of depleted uranium impairs progeny development at the molecular and histological levels

    PubMed Central

    Gombeau, Kewin; Murat El Houdigui, Sophia; Floriani, Magali; Camilleri, Virginie; Cavalie, Isabelle; Adam-Guillermin, Christelle

    2017-01-01

    Uranium is an actinide naturally found in the environment. Anthropogenic activities lead to the release of increasing amounts of uranium and depleted uranium (DU) in the environment, posing potential risks to aquatic organisms due to radiological and chemical toxicity of this radionucleide. Although environmental contaminations with high levels of uranium have already been observed, chronic exposures of non-human species to levels close to the environmental quality standards remain scarcely characterized. The present study focused on the identification of the molecular pathways impacted by a chronic exposure of zebrafish to 20 μg/L of DU during 10 days. The transcriptomic effects were evaluated by the use of the mRNAseq analysis in three organs of adult zebrafish, the brain the testis and the ovaries, and two developmental stages of the adult fish progeny, two-cells embryo and four-days larvae. The results highlight generic effects on the cell adhesion process, but also specific transcriptomic responses depending on the organ or the developmental stage investigated. The analysis of the transgenerational effects of DU-exposure on the four-day zebrafish larvae demonstrate an induction of genes involved in oxidative response (cat, mpx, sod1 and sod2), a decrease of expression of the two hatching enzymes (he1a and he1b), the deregulation of the expression of gene coding for the ATPase complex and the induction of cellular stress. Electron microscopy analysis of skeletal muscles on the four-days larvae highlights significant histological impacts on the ultrastructure of both the mitochondria and the myofibres. In addition, the comparison with the transcriptomic data obtained for the acetylcholine esterase mutant reveals the induction of protein-chaperons in the skeletal muscles of the progeny of fish chronically exposed to DU, pointing towards long lasting effects of this chemical in the muscles. The results presented in this study support the hypothesis that a chronic

  5. Radon Levels Measured at a Touristic Thermal Spa Resort in Montagu (South Africa) and Associated Effective Doses.

    PubMed

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

    2016-09-01

    Radon activity concentrations (in water and in air) were measured at 13 selected locations at the Avalon Springs thermal spa resort in Montagu (Western Cape, South Africa) to estimate the associated effective dose received by employees and visitors. A RAD-7 detector (DURRIDGE), based on alpha spectrometry, and electret detectors (E-PERM®Radelec) were used for these radon measurements. The primary source of radon was natural thermal waters from the hot spring, which were pumped to various locations on the resort, and consequently a range of radon in-water analyses were performed. Radon in-water activity concentration as a function of time (short term and long term measurements) and spatial distributions (different bathing pools, etc.) were studied. The mean radon in-water activity concentrations were found to be 205 ± 6 Bq L (source), 112 ± 5 Bq L (outdoor pool) and 79 ± 4 Bq L (indoor pool). Radon in-air activity concentrations were found to range between 33 ± 4 Bq m (at the outside bar) to 523 ± 26 Bq m (building enclosing the hot spring's source). The most significant potential radiation exposure identified is that due to inhalation of air rich in radon and its progeny by the resort employees. The annual occupational effective dose due to the inhalation of radon progeny ranges from 0.16 ± 0.01 mSv to 0.40 ± 0.02 mSv. For the water samples collected, the Ra in-water activity concentrations from samples collected were below the lower detection limit (~0.7 Bq L) of the γ-ray detector system used. No significant radiological health risk can be associated with radon and progeny from the hot spring at the Avalon Springs resort.

  6. 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.

  7. Relationship between DNA damage in sperm after ex vivo exposure and abnormal embryo development in the progeny of the three-spined stickleback.

    PubMed

    Santos, R; Palos-Ladeiro, M; Besnard, A; Porcher, J M; Bony, S; Sanchez, W; Devaux, A

    2013-04-01

    Many xenobiotics released in the aquatic environment exhibit a genotoxic potential toward organisms. Long term exposure to such compounds is expected to lead to multigenerational reproductive defects, further influencing the recruitment rate and hence, the population dynamics. Paternal exposure to genotoxicants was previously shown to increase abnormal development in the progeny of mammalian or aquatic species. The aim of this study was to evaluate the relationship between DNA damage in sperm of the fish three-spined stickleback and progeny developmental defects. Spermatozoa were exposed ex vivo to an alkylating agent (methyl methanesulfonate) before in vitro fertilization and DNA damage was assessed by the alkaline comet assay. A significant relationship between abnormal development and sperm DNA damage was underlined. This study illustrates the interest to use germ cell DNA damage after ex vivo exposure to evaluate the impact of genotoxic compounds on progeny fitness in aquatic organisms.

  8. Estimation of Radiological Dose From Progeny of 222Rn and 220Rn Using DTPS/DRPS and Wire-Mesh-Capped Progeny Sensors

    PubMed Central

    Jakhu, Rajan; Bangotra, Pargin; Mittal, Harish Mohan

    2016-01-01

    Radon (222Rn) and its decay products are the major sources of natural radiation exposure to general population. The activity concentrations of unattached and attached short-lived 222Rn and thoron (220Rn) progeny in indoor environment of some dwellings of the Jalandhar and Kapurthala districts of Punjab had been calculated using the deposition-based progeny sensors (DRPS/DTPS) and wire-mesh-capped (DRPS/DTPS) progeny sensors. The observed concentration of attached 222Rn and 220Rn progeny showed the variation from 5 to 21 Bq·m−3 and 0.3 to 1.7 Bq·m−3, respectively. The activity concentration of the unattached 222Rn and 220Rn progeny varies from 1 to 5 Bq·m−3 and 0.1 to 0.6 Bq·m−3, respectively. The average unattached fraction of 222Rn and 220Rn progeny is 0.2 and 0.1. The average value of the indoor aerosol concentration attachment rate of 222Rn and 220Rn progeny is 2251 cm−3, 24 ms−1, and 617 ms−1. Relation among the unattached fraction and attachment rate is established, and the obtained results of dose conversion factors show the significance of the nano-sized 222Rn decay products in 222Rn dosimetry. PMID:27994523

  9. Estimation of Radiological Dose From Progeny of (222)Rn and (220)Rn Using DTPS/DRPS and Wire-Mesh-Capped Progeny Sensors.

    PubMed

    Mehra, Rohit; Jakhu, Rajan; Bangotra, Pargin; Mittal, Harish Mohan

    2016-01-01

    Radon ((222)Rn) and its decay products are the major sources of natural radiation exposure to general population. The activity concentrations of unattached and attached short-lived (222)Rn and thoron ((220)Rn) progeny in indoor environment of some dwellings of the Jalandhar and Kapurthala districts of Punjab had been calculated using the deposition-based progeny sensors (DRPS/DTPS) and wire-mesh-capped (DRPS/DTPS) progeny sensors. The observed concentration of attached (222)Rn and (220)Rn progeny showed the variation from 5 to 21 Bq·m(-3) and 0.3 to 1.7 Bq·m(-3), respectively. The activity concentration of the unattached (222)Rn and (220)Rn progeny varies from 1 to 5 Bq·m(-3) and 0.1 to 0.6 Bq·m(-3), respectively. The average unattached fraction of (222)Rn and (220)Rn progeny is 0.2 and 0.1. The average value of the indoor aerosol concentration attachment rate of (222)Rn and (220)Rn progeny is 2251 cm(-3), 24 ms(-1), and 617 ms(-1). Relation among the unattached fraction and attachment rate is established, and the obtained results of dose conversion factors show the significance of the nano-sized (222)Rn decay products in (222)Rn dosimetry.

  10. 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).

  11. 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.

  12. 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.

  13. 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.

  14. Development of a new thoron progeny detector based on SSNTD and the collection by an electric field.

    PubMed

    Bi, L; Tschiersch, J; Meisenberg, O; Wielunski, M; Li, J L; Shang, B

    2011-05-01

    The importance of (220)Rn (thoron) progeny for human exposure has been widely recognised in the past decades. Since no stable equilibrium factor was found between indoor thoron and its progeny, and the concentration of thoron progeny varies with time, it is necessary to develop detectors for long-term measurement that directly sample and detect thoron progeny. However, power supply of this kind of detectors has always been a problem. In this study, a set of device that is suitable for long-term measurement is introduced. A high-voltage electric field was formed for the collection of charged aerosols attached by (222)Rn (radon) and thoron progenies on solid-state nuclear track detector. Impact from radon progeny could be eliminated with a shield of Al foil of appropriate thickness. Tests were made both in an experimental house and in a thoron chamber in Helmholtz Zentrum München to determine the parameters and to verify the universality under different conditions.

  15. 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.

  16. Study of radon dispersion in typical dwelling using CFD modeling combined with passive-active measurements

    NASA Astrophysics Data System (ADS)

    Rabi, R.; Oufni, L.

    2017-10-01

    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. Indoor air conditions and ventilation systems strongly influence the indoor radon concentration. This study focuses on investigating both numerically and experimentally the influence of environmental conditions on the indoor radon concentration and spatial distribution. The numerical results showed that ventilation rate, temperature and humidity have significant impacts on both radon content and distribution. The variations of radon concentration with the ventilation, temperature and relative humidity are discussed. The measurement results show the diurnal variations of the indoor radon concentration are found to exhibit a positive correlation with relative humidity and negatively correlate with the air temperature. The analytic solution is used to validate the numeric results. The comparison amongst analytical, numerical and measurement results shows close agreement.

  17. Lorenz Curve and Gini coefficient: novel tools for analysing seasonal variation of environmental radon gas.

    PubMed

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

    2009-06-01

    Using a methodology derived from Economics, the Lorenz Curve and Gini Coefficient are introduced as tools for investigating and quantifying seasonal variability in environmental radon gas concentration. While the Lorenz Curve presents a graphical view of the cumulative exposure during the course of the time-frame of interest, typically one year, the Gini Coefficient distils this data still further, to provide a single-parameter measure of temporal clustering. Using the assumption that domestic indoor radon concentrations show annual cyclic behaviour, generally higher in the winter months than in summer, published data on seasonal variability of domestic radon concentration levels, in various areas of the UK, Europe, Asia and North America, are analysed. The results demonstrate significantly different annual variation profiles between domestic radon concentrations in different countries and between regions within a country, highlighting the need for caution in ascribing seasonal correction factors to extended geographical areas. The underlying geography, geology and meteorology of a region have defining influences on the seasonal variability of domestic radon concentration, and some examples of potential associations between the Gini Coefficient and regional geological and geographical characteristics are proposed. Similar differences in annual variation profiles are found for soil-gas radon measured as a function of depth at a common site, and among the activity levels of certain radon progeny species, specifically (214)Bi deposited preferentially in human body-fat by decay of inhaled radon gas. Conclusions on the association between these observed measures of variation and potential underlying defining parameters are presented.

  18. 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.

  19. 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

  20. Gestational exposure to yellow fever vaccine at different developmental stages induces behavioral alterations in the progeny.

    PubMed

    Marianno, P; Salles, M J S; Sonego, A B; Costa, G A; Galvão, T C; Lima, G Z; Moreira, E G

    2013-01-01

    The most effective method to prevent yellow fever and control the disease is a vaccine made with attenuated live virus. Due to the neurological tropism of the virus, preventive vaccination is not recommended for infants under 6 months and for pregnant women. However there is a paucity of data regarding the safety for pregnant women and there are no experimental studies investigating adverse effects to the offspring after maternal exposure to the vaccine. This study aimed to investigate, in mice, the effects of maternal exposure to the yellow fever vaccine at three different gestational ages on the physical and behavioral development of the offspring. Pregnant Swiss mice received a single subcutaneous injection of water for injection (control groups) or 2 log Plaque Forming Units (vaccine-treated groups) of the yellow fever vaccine on gestational days (GD) 5, 10 or 15. Neither maternal signs of toxicity nor alterations in physical development and reflex ontogeny of the offspring were observed in any of the groups. Data from behavioral evaluation indicated that yellow fever vaccine exposure induced motor hypoactivity in 22-day-old females independent of the day of exposure; and in 60-day-old male and female pups exposed at GD 10. Moreover, 22-day-old females also presented with a deficit in habituation memory. Altogether, these results indicate that in utero exposure to the yellow fever vaccine may induce behavioral alterations in the pups that may persist to adulthood in the absence of observed maternal toxicity or disruption of physical development milestones or reflex ontogeny. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. 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

  2. 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)

  3. 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

  4. Gestational exposure to diethylstilbestrol alters cardiac structure/function, protein expression and DNA methylation in adult male mice progeny

    SciTech Connect

    Haddad, Rami; Kasneci, Amanda; Mepham, Kathryn; Sebag, Igal A.; and others

    2013-01-01

    Pregnant women, and thus their fetuses, are exposed to many endocrine disruptor compounds (EDCs). Fetal cardiomyocytes express sex hormone receptors making them potentially susceptible to re-programming by estrogenizing EDCs. Diethylstilbestrol (DES) is a proto-typical, non-steroidal estrogen. We hypothesized that changes in adult cardiac structure/function after gestational exposure to the test compound DES would be a proof in principle for the possibility of estrogenizing environmental EDCs to also alter the fetal heart. Vehicle (peanut oil) or DES (0.1, 1.0 and 10.0 μg/kg/da.) was orally delivered to pregnant C57bl/6n dams on gestation days 11.5–14.5. At 3 months, male progeny were left sedentary or were swim trained for 4 weeks. Echocardiography of isoflurane anesthetized mice revealed similar cardiac structure/function in all sedentary mice, but evidence of systolic dysfunction and increased diastolic relaxation after swim training at higher DES doses. The calcium homeostasis proteins, SERCA2a, phospholamban, phospho-serine 16 phospholamban and calsequestrin 2, are important for cardiac contraction and relaxation. Immunoblot analyses of ventricle homogenates showed increased expression of SERCA2a and calsequestrin 2 in DES mice and greater molecular remodeling of these proteins and phospho-serine 16 phospholamban in swim trained DES mice. DES increased cardiac DNA methyltransferase 3a expression and DNA methylation in the CpG island within the calsequestrin 2 promoter in heart. Thus, gestational DES epigenetically altered ventricular DNA, altered cardiac function and expression, and reduced the ability of adult progeny to cardiac remodel when physically challenged. We conclude that gestational exposure to estrogenizing EDCs may impact cardiac structure/function in adult males. -- Highlights: ► Gestational DES changes cardiac SERCA2a and CASQ2 expression. ► Echocardiography identified systolic dysfunction and increased diastolic relaxation. ► DES

  5. Neurobehavioral effects of sodium tungstate exposure on rats and their progeny.

    PubMed

    McInturf, Shawn M; Bekkedal, Marni Y-V; Wilfong, Erin; Arfsten, Darryl; Gunasekar, Palur G; Chapman, Gail D

    2008-01-01

    The use of tungsten as a replacement for lead and depleted uranium in munitions began in the mid 1990's. Recent reports demonstrate tungsten solubilizes in soil and can migrate into drinking water supplies and therefore is a potential health risk to humans. This study evaluated the reproductive and neurobehavioral effects of sodium tungstate in Sprague-Dawley rats following 70 days of daily pre- and postnatal exposure. Adult male and female rats were orally dosed with diH(2)O vehicle, 5 or 125 mg/kg/day of sodium tungstate through mating, gestation, and weaning (PND 0-20). Daily administration of sodium tungstate produced no overt evidence of toxicity and had no apparent effect on mating success or offspring physical development. Distress vocalizations were elevated in the highest dose group. There was no treatment related effect on righting reflex latencies, however, the males had significantly shorter latencies than the females. Locomotor activity was affected in both the low and high dose groups of F0 females. Those in the low dose group showed increased distance traveled, more time in ambulatory movements, and less time in stereotypic behavior than controls or high dose animals. The high dose group had more time in stereotypical movements than controls, and less time resting than controls and the lowest exposure group. Maternal retrieval was not affected by sodium tungstate exposure and there were no apparent effects of treatment on F1 acoustic startle response or water maze navigation. Overall, the results of this study suggest pre- and postnatal oral exposure to sodium tungstate may produce subtle neurobehavioral effects in offspring related to motor activity and emotionality. These findings warrant further investigation to characterize the neurotoxicity of sodium tungstate on dams and their developing pups.

  6. Effects of maternal nicotine exposure on thyroid hormone metabolism and function in adult rat progeny.

    PubMed

    Lisboa, P C; de Oliveira, E; Manhães, A C; Santos-Silva, A P; Pinheiro, C R; Younes-Rapozo, V; Faustino, L C; Ortiga-Carvalho, T M; Moura, E G

    2015-03-01

    Postnatal nicotine exposure leads to obesity and hypothyroidism in adulthood. We studied the effects of maternal nicotine exposure during lactation on thyroid hormone (TH) metabolism and function in adult offspring. Lactating rats received implants of osmotic minipumps releasing nicotine (NIC, 6 mg/kg per day s.c.) or saline (control) from postnatal days 2 to 16. Offspring were killed at 180 days. We measured types 1 and 2 deiodinase activity and mRNA, mitochondrial α-glycerol-3-phosphate dehydrogenase (mGPD) activity, TH receptor (TR), uncoupling protein 1 (UCP1), hypothalamic TRH, pituitary TSH, and in vitro TRH-stimulated TSH secretion. Expression of deiodinase mRNAs followed the same profile as that of the enzymatic activity. NIC exposure caused lower 5'-D1 and mGPD activities; lower TRβ1 content in liver as well as lower 5'-D1 activity in muscle; and higher 5'-D2 activity in brown adipose tissue (BAT), heart, and testis, which are in accordance with hypothyroidism. Although deiodinase activities were not changed in the hypothalamus, pituitary, and thyroid of NIC offspring, UCP1 expression was lower in BAT. Levels of both TRH and TSH were lower in offspring exposed to NIC, which presented higher basal in vitro TSH secretion, which was not increased in response to TRH. Thus, the hypothyroidism in NIC offspring at adulthood was caused, in part, by in vivo TRH-TSH suppression and lower sensitivity to TRH. Despite the hypothyroid status of peripheral tissues, these animals seem to develop an adaptive mechanism to preserve thyroxine to triiodothyronine conversion in central tissues. © 2015 Society for Endocrinology.

  7. Transient gestational exposure to drinking water containing excess hexavalent Chromium modifies insulin signaling in liver and skeletal muscle of rat progeny.

    PubMed

    Shobana, Navaneethabalakrishnan; Aruldhas, Mariajoseph Michael; Tochhawng, Lalmuankimi; Loganathan, Ayyalu; Balaji, Sadhasivam; Kumar, Mani Kathiresh; Banu, Liaquat Alikhan Sheerin; Navin, Ajit Kumar; Mayilvanan, Chinnaiyan; Ilangovan, Ramachandran; Balasubramanian, Karundevi

    2017-09-11

    Chromium (Cr), an essential micronutrient potentiates insulin action, whereas excess hexavalent Cr (CrVI) acts as an endocrine disruptor. Pregnant mothers living in areas abutting industries using the metal and chromite ore dumps are exposed to ground water contaminated with Cr. Nevertheless, the impact of prenatal exposure to excess CrVI on insulin signaling in the progeny remains obscure. We tested the hypothesis "transient gestational exposure to drinking water containing excess CrVI may modify insulin signaling during postnatal life". Pregnant Wistar rats were given drinking water containing 50, 100 and 200 ppm CrVI (K2Cr2O7) from gestational day 9-14 encompassing the period of organogenesis; the male progenies were tested at postnatal day 60. Neither fasting blood glucose nor oral glucose tolerance was altered in CrVI treated progeny. Nevertheless, western blot detection pointed out attenuated expression level of insulin receptor (IR), its downstream signaling molecules (IRS-1, pIRS-1(Tyr632), Akt and pAkt(Ser473)) and organ specific glucose transporters (GLUT2 in liver and GLUT4 in gastrocnemius muscle), along with a significant increase in serum insulin level in male progenies exposed to CrVI. While (14)C-2-deoxy glucose uptake increased in the liver, the same decreased in the skeletal muscle whereas, (14)C-glucose oxidation recorded a consistent decrease in both tissues of CrVI exposed rats. These findings support our hypothesis and suggest that transient gestational exposure to excess CrVI may affect insulin signaling and glucose oxidation in the progeny, predictably rendering them vulnerable to insulin resistance. Copyright © 2017. Published by Elsevier B.V.

  8. 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.

  9. Prenatal cocaine exposure impairs cognitive function of progeny via insulin growth factor II epigenetic regulation.

    PubMed

    Zhao, Qian; Hou, Jing; Chen, Bo; Shao, Xue; Zhu, Ruiming; Bu, Qian; Gu, Hui; Li, Yan; Zhang, Baolai; Du, Changman; Fu, Dengqi; Kong, Jueying; Luo, Li; Long, Hailei; Li, Hongyu; Deng, Yi; Zhao, Yinglan; Cen, Xiaobo

    2015-10-01

    Studies have showed that prenatal cocaine exposure (PCOC) can impair cognitive function and social behavior of the offspring; however, the mechanism underlying such effect is poorly understood. Insulin-like growth factor II (Igf-II), an imprinted gene, has a critical role in memory consolidation and enhancement. We hypothesized that epigenetic regulation of hippocampal Igf-II may attribute to the cognitive deficits of PCOC offspring. We used Morris water maze and open-field task to test the cognitive function in PCOC offspring. The epigenetic alteration involved in hippocampal Igf-II expression deficit in PCOC offspring was studied by determining Igf-II methylation status, DNA methyltransferases (DNMT) expressions and L-methionine level. Moreover, IGF-II rescue experiments were performed and the downstream signalings were investigated in PCOC offspring. In behavioral tests, we observed impaired spatial learning and memory and increased anxiety in PCOC offspring; moreover, hippocampal IGF-II mRNA and protein expressions were significantly decreased. Hippocampal methylation of cytosine-phospho-guanine (CpG) dinucleotides in differentially methylated region (DMR) 2 of Igf-II was elevated in PCOC offspring, which may be driven by the upregulation of L-methionine and DNA methyltransferase (DNMT) 1. Importantly, intra-hippocampal injection of recombinant IGF-II reactivated the repressed calcium calmodulin kinase II α (CaMKIIα) and reversed cognitive deficits in PCOC offspring. Collectively, our findings suggest that cocaine exposure during pregnancy impairs cognitive function of offspring through epigenetic modification of Igf-II gene. Enhancing IGF-II signaling may represent a novel therapeutical strategy for cocaine-induced cognitive impairment.

  10. 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.

  11. 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

  12. 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.

  13. 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.

  14. 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.

  15. 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)

  16. 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)

  17. The health risks of radon: The BEIR IV report and beyond

    SciTech Connect

    Fabrikant, J.I.

    1989-06-01

    The National Academy of Sciences' BEIR IV Report deals with the health effects in human populations exposed to internally-deposited alpha-emitting radionuclides and their decay products. Quantitative risk estimates for cancer induction are derived, mainly from analyses of epidemiological data. The Report addresses the health outcomes of exposure to radon and its daughters, primarily lung cancer risks of worker exposure to radon progeny in underground mines and in the general public in indoor domestic environments. An excess relative risk model of lung cancer mortality and exposure to radon progeny is developed; this models the excess risk per Working Level Month in terms of time intervals prior to an attained age, and is dependent on time-since-exposure and age at risk. Risk projections are presented and cover exposure situations of current public health concern. For example, the lifetime risk of lung cancer mortality due to lifetime exposure to radon progeny in terms of WLM and alpha-particle dose to the target cells of the bronchial epithelium is estimated to be 350 excess deaths per million person-WLM. Lifetime exposure to 1 WLM y /sub /minus/1/ is estimated to increase the number of deaths due to lung cancer by a factor of about 1.5 over the current rate for both males and females in a population having the current prevalence of cigarette-smoking. Occupational exposure to 4 WLM y/sub /minus/1/ from ages 20 y to 40 y is projected to increase lung cancer deaths by a factor of 1.6 over the current rate of this age cohort in the general population. In all of these cases, most of the increased risk occurs to smokers for who the risk is up to ten times greater than for nonsmokers. 10 refs., 1 tab.

  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. 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.

  20. 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.

  1. 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

  2. Deposition of thoron progeny in human head airways

    SciTech Connect

    Cheng, Yungsung; Su, Yinfong; Yeh, Hsuchi ); Swift, D.L. )

    1993-05-01

    Radon and thoron progeny are ultrafine particles in the size range of 1-200 nm, depending on whether or not they are attached to other aerosol particles. The diffusion coefficient of radon progeny is a critical parameter in determining its dynamics while airborne. Depending on their diffusion coefficient and the breathing pattern of the subject, ultrafine particles have been shown to deposit in the nasal or oral airways. Substantial deposition in the head airways reduces the amount of radioactivity that deposits in the tracheobronchial tree. Thus, for accurate dosimetric calculations, it is important to know the deposition fraction of radon progeny in the head airways. Several adult head airway models were used to study the radon progeny deposition in human nasal and oral airways. Radon-220 progeny ([sup 212]Pb) were used in the study. The particle size as measured by a graded screen diffusion battery was between 1.2 and 1.7 nm, indicating that the particles were molecular clusters. Deposition was measured by collecting filter samples before and after the model and gamma counting the [sup 212]Pb. Experiments were performed under the constant flow rates of 4-20 L/min. Deposition efficiencies were between 63% and 85% in the nasal airway and 48% and 78% in the oral airway. Previously reported deposition data in the same airway model for ultrafine particles between 4.6 and 200 nm and the deposition data of radon progeny were used to establish a turbulent deposition equation covering particle sizes from 1 to 200 nm, the entire size range for attached and unattached radon progeny. 23 refs., 10 figs., 6 tabs.

  3. Maternal low-dose estradiol-17β exposure during pregnancy impairs postnatal progeny weight development and body composition

    SciTech Connect

    Werner Fürst, Rainer; Pistek, Veronika Leopoldine; Kliem, Heike; Skurk, Thomas; Hauner, Hans; Meyer, Heinrich Herman Dietrich; Ulbrich, Susanne Ernestine

    2012-09-15

    Endocrine disrupting chemicals with estrogenic activity play an important role as obesogens. However, studies investigating the most potent natural estrogen, estradiol-17β (E2), at low dose are lacking. We examined endocrine and physiological parameters in gilts receiving distinct concentrations of E2 during pregnancy. We then investigated whether adverse effects prevail in progeny due to a potential endocrine disruption. E2 was orally applied to gilts during the entire period of pregnancy. The concentrations represented a daily consumption at the recommended ADI level (0.05 μg/kg body weight/day), at the NOEL (10 μg/kg body weight/day) and at a high dosage (1000 μg/kg body weight/day). Plasma hormone concentrations were determined using enzyme immuno assays. Offspring body fat was assessed by dual-energy X-ray absorptiometry scanning. In treated gilts receiving 1000 μg E2/kg body weight/day we found significantly elevated plasma E2 levels during pregnancy, paralleled by an increased weight gain. While offspring showed similar weight at birth, piglets exhibited a significant reduction in weight at weaning even though their mothers had only received 0.05 μg E2/kg body weight/day. At 8 weeks of age, specifically males showed a significant increase in overall body fat percentage. In conclusion, prenatal exposure to low doses of E2 affected pig offspring development in terms of body weight and composition. In line with findings from other obesogens, our data suggest a programming effect during pregnancy for E2 causative for the depicted phenotypes. Therefore, E2 exposure may imply a possible contribution to childhood obesity. -- Highlights: ► We investigate the potential role of estradiol-17β (E2) as an obesogen. ► We orally apply E2 at the ADI, NOEL and a high dose to gilts during pregnancy. ► Offspring weight is similar at birth but reduced at weaning even after ADI treatment. ► Male offspring only exhibit an increase in overall body fat percentage

  4. 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.

  5. 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.

  6. Radon emanation fractions from concretes containing fly ash and metakaolin.

    PubMed

    Taylor-Lange, Sarah C; Juenger, Maria C G; Siegel, Jeffrey A

    2014-01-01

    Radon ((222)Rn) and progenies emanate from soil and building components and can create an indoor air quality hazard. In this study, nine concrete constituents, including the supplementary cementitious materials (SCMs) fly ash and metakaolin, were used to create eleven different concrete mixtures. We investigated the effect of constituent radium specific activity, radon effective activity and emanation fraction on the concrete emanation fraction and the radon exhalation rate. Given the serious health effects associated with radionuclide exposure, experimental results were coupled with Monte Carlo simulations to demonstrate predictive differences in the indoor radon concentration due to concrete mixture design. The results from this study show that, on average, fly ash constituents possessed radium specific activities ranging from 100 Bq/kg to 200 Bq/kg and emanation fractions ranging from 1.1% to 2.5%. The lowest emitting concrete mixture containing fly ash resulted in a 3.4% reduction in the concrete emanation fraction, owing to the relatively low emanation that exists when fly ash is part of concrete. On average, the metakaolin constituents contained radium specific activities ranging from 67 Bq/kg to 600 Bq/kg and emanation fractions ranging from 8.4% to 15.5%, and changed the total concrete emanation fraction by roughly ±5% relative to control samples. The results from this study suggest that SCMs can reduce indoor radon exposure from concrete, contingent upon SCM radionucleotide content and emanation fraction. Lastly, the experimental results provide SCM-specific concrete emanation fractions for indoor radon exposure modeling.

  7. A Calibration and Quality Assurance Program for Environmental Radon Measurements

    PubMed Central

    Fisenne, Isabel M.; George, Andreas C.; Keller, Helen W.

    1990-01-01

    The ideal facility for assessing the quality of radon measurements at environmental levels consists of: (1) an instrument whose response to radon and its progeny is determined from measurements of a certified or standard 226Ra source, and (2) a calibration room with a known radon concentration. The linkage between these two elements and additional quality control requirements are discussed here for some Environmental Measurements Laboratory radon measurements programs. PMID:28179764

  8. 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

  9. 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

  10. Radon emanation from low-grade uranium ore.

    PubMed

    Sahu, Patitapaban; Mishra, Devi Prasad; Panigrahi, Durga Charan; Jha, Vivekanand; Patnaik, R Lokeswara

    2013-12-01

    Estimation of radon emanation in uranium mines is given top priority to minimize the risk of inhalation exposure due to short-lived radon progeny. This paper describes the radon emanation studies conducted in the laboratory as well as inside an operating underground uranium mine at Jaduguda, India. Some of the important parameters, such as grade/(226)Ra activity, moisture content, bulk density, porosity and emanation fraction of ore, governing the migration of radon through the ore were determined. Emanation from the ore samples in terms of emanation rate and emanation fraction was measured in the laboratory under airtight condition in glass jar. The in situ radon emanation rate inside the mine was measured from drill holes made in the ore body. The in situ(222)Rn emanation rate from the mine walls varied in the range of 0.22-51.84 × 10(-3) Bq m(-2) s(-1) with the geometric mean of 8.68 × 10(-3) Bq m(-2) s(-1). A significant positive linear correlation (r = 0.99, p < 0.001) between in situ(222)Rn emanation rate and the ore grade was observed. The emanation fraction of the ore samples, which varied in the range of 0.004-0.089 with mean value of 0.025 ± 0.02, showed poor correlation with ore grade and porosity. Empirical relationships between radon emanation rate and the ore grade/(226)Ra were also established for quick prediction of radon emanation rate from the ore body.

  11. 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

  12. 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.

  13. 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.

  14. Analysis of the main factors affecting the evaluation of the radon dose in workplaces: the case of tourist caves.

    PubMed

    Sainz, Carlos; Quindós, Luis Santiago; Fuente, Ismael; Nicolás, Jorge; Quindós, Luis

    2007-07-16

    High concentrations of radon exist in several workplaces like tourist caves mainly because of the low ventilation rates existing at these enclosures. In this sense, in its 1990 publication, the ICRP recommended that high exposures of radon in workplaces should be considered as occupational exposure. In developed caves in which guides provide tours for the general public great care is needed for taking remedial actions concerning radon, because in some circumstances forced ventilation may alter the humidity inside the cave affecting some of the formations or paintings that attract tourists. Tourist guides can work about 1900 h per year, so the only option to protect them and other cave workers from radon exposure is to apply an appropriate system of radiation protection mainly based on limitation of exposure by restricting the amount of time spent in the cave. Because of the typical environmental conditions inside the caves, the application of these protecting actions requires to know some indoor air characteristics like particle concentration, as well as radon progeny behaviour in order to get more realistic effective dose values In this work the results of the first two set of radon measurements program carried out in 10 caves located in the region of Cantabria (Spain) are presented.

  15. 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.

  16. 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.

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

    PubMed

    Zunić, Z S; Celiković, I; Tokonami, S; Ishikawa, T; Ujić, P; Onischenko, A; Zhukovsky, M; Milić, G; Jakupi, B; Cuknić, O; Veselinović, N; Fujimoto, K; Sahoo, S K; Yarmoshenko, I

    2010-10-01

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

  18. 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.

  19. Design, characterization and use of replicate human upper airways for radon dosimetry studies

    SciTech Connect

    Swift, D.L.; Cheng, Y.S.; Su, Y.F.; Yeh, H.C.

    1992-12-31

    The size distribution of inhaled radon progeny aerosols is a significant factor in dosimetry. The role of the airways above the trachea is an important determinant of the respiratory distribution of both attached and unattached progeny aerosols. In order to provide information on the effect of particle size and breathing conditions on the overall and local deposition, we have developed a method to produce a replicate airway model from an in vivo magnetic resonance imaging coronal scan. The model consists of a sandwich of methacrylate elements, each element having the thickness of the scan interval. The transition between successive scan outlines traced on the front and back surfaces of each element is handsculpted in the plastic. The hollow model of the nasal passages thus produced has been characterized both morphologically and fluid-mechanically and has a flow resistance typical of a normal adult. The model has several distinct advantages for studies of radon progeny aerosol deposition. After exposure to a radioaerosol (or to an aerosol of an otherwise measurable substance) the individual elements can be separated to determine local deposition. The dimensions of specific upper-airway regions can be changed by replacing a small number of elements. The model has been incorporated in an exposure system for determining overall nandregional deposition of aerosols whose median diameter is approximately 1.7 nm. Measurements at several flow rates are presented to demonstrate use of the model in radon dosimetry. The model should also be useful for determining the airway deposition of other environmental aerosols.

  20. A complete low cost radon detection system.

    PubMed

    Bayrak, A; Barlas, E; Emirhan, E; Kutlu, Ç; Ozben, C S

    2013-08-01

    Monitoring the (222)Rn activity through the 1200 km long Northern Anatolian fault line, for the purpose of earthquake precursory, requires large number of cost effective radon detectors. We have designed, produced and successfully tested a low cost radon detection system (a radon monitor). In the detector circuit of this monitor, First Sensor PS100-7-CER-2 windowless PIN photodiode and a custom made transempedence/shaping amplifier were used. In order to collect the naturally ionized radon progeny to the surface of the PIN photodiode, a potential of 3500 V was applied between the conductive hemi-spherical shell and the PIN photodiode. In addition to the count rate of the radon progeny, absolute pressure, humidity and temperature were logged during the measurements. A GSM modem was integrated to the system for transferring the measurements from the remote locations to the data process center.

  1. Inhalation exposures due to radon and thoron ((222)Rn and (220)Rn): Do they differ in high and normal background radiation areas in India?

    PubMed

    Mishra, Rosaline; Sapra, B K; Prajith, R; Rout, R P; Jalaluddin, S; Mayya, Y S

    2015-09-01

    In India, High Background Radiation Areas (HBRAs) due to enhanced levels of naturally occurring radionuclides in soil (thorium and, to a lesser extent, uranium), are located along some parts of the coastal tracts viz. the coastal belt of Kerala, Tamilnadu and Odisha. It is conjectured that these deposits will result in higher emissions of radon isotopes ((222)Rn and (220)Rn) and their daughter products as compared to Normal Background Radiation Areas (NBRAs). While the annual external dose rates contributed by gamma radiations in these areas are about 5-10 times higher, the extent of increase in the inhalation dose rates attributable to (222)Rn and (220)Rn and their decay products is not well quantified. Towards this, systematic indoor surveys were conducted wherein simultaneous measurements of time integrated (222)Rn and (220)Rn gas and their decay product concentrations was carried out in around 800 houses in the HBRAs of Kerala and Odisha to estimate the inhalation doses. All gas measurements were carried out using pin-hole cup dosimeters while the progeny measurements were with samplers and systems based on the Direct radon/thoron Progeny sensors (DRPS/DTPS). To corroborate these passive measurements of decay products concentrations, active sampling was also carried out in a few houses. The results of the surveys provide a strong evidence to conclude that the inhalation doses due to (222)Rn and (220)Rn gas and their decay products in these HBRAs are in the same range as observed in the NBRAs in India.

  2. Maternal Exposure to Cadmium and Manganese Impairs Reproduction and Progeny Fitness in the Sea Urchin Paracentrotus lividus.

    PubMed

    Migliaccio, Oriana; Castellano, Immacolata; Cirino, Paola; Romano, Giovanna; Palumbo, Anna

    2015-01-01

    Metal contamination represents one of the major sources of pollution in marine environments. In this study we investigated the short-term effects of ecologically relevant cadmium and manganese concentrations (10(-6) and 3.6 x 10(-5) M, respectively) on females of the sea urchin Paracentrotus lividus and their progeny, reared in the absence or presence of the metal. Cadmium is a well-known heavy metal, whereas manganese represents a potential emerging contaminant, resulting from an increased production of manganese-containing compounds. The effects of these agents were examined on both P. lividus adults and their offspring following reproductive state, morphology of embryos, nitric oxide (NO) production and differential gene expression. Here, we demonstrated that both metals differentially impaired the fertilization processes of the treated female sea urchins, causing modifications in the reproductive state and also affecting NO production in the ovaries. A detailed analysis of the progeny showed a high percentage of abnormal embryos, associated to an increase in the endogenous NO levels and variations in the transcriptional expression of several genes involved in stress response, skeletogenesis, detoxification, multi drug efflux processes and NO production. Moreover, we found significant differences in the progeny from females exposed to metals and reared in metal-containing sea water compared to embryos reared in non-contaminated sea water. Overall, these results greatly expanded previous studies on the toxic effects of metals on P. lividus and provided new insights into the molecular events induced in the progeny of sea urchins exposed to metals.

  3. Maternal Exposure to Cadmium and Manganese Impairs Reproduction and Progeny Fitness in the Sea Urchin Paracentrotus lividus

    PubMed Central

    Migliaccio, Oriana; Castellano, Immacolata; Cirino, Paola; Romano, Giovanna; Palumbo, Anna

    2015-01-01

    Metal contamination represents one of the major sources of pollution in marine environments. In this study we investigated the short-term effects of ecologically relevant cadmium and manganese concentrations (10-6 and 3.6 x 10-5 M, respectively) on females of the sea urchin Paracentrotus lividus and their progeny, reared in the absence or presence of the metal. Cadmium is a well-known heavy metal, whereas manganese represents a potential emerging contaminant, resulting from an increased production of manganese-containing compounds. The effects of these agents were examined on both P. lividus adults and their offspring following reproductive state, morphology of embryos, nitric oxide (NO) production and differential gene expression. Here, we demonstrated that both metals differentially impaired the fertilization processes of the treated female sea urchins, causing modifications in the reproductive state and also affecting NO production in the ovaries. A detailed analysis of the progeny showed a high percentage of abnormal embryos, associated to an increase in the endogenous NO levels and variations in the transcriptional expression of several genes involved in stress response, skeletogenesis, detoxification, multi drug efflux processes and NO production. Moreover, we found significant differences in the progeny from females exposed to metals and reared in metal-containing sea water compared to embryos reared in non-contaminated sea water. Overall, these results greatly expanded previous studies on the toxic effects of metals on P. lividus and provided new insights into the molecular events induced in the progeny of sea urchins exposed to metals. PMID:26125595

  4. Is thoron a problem in Swedish dwellings? Results of measurements of concentrations of thoron and its progeny.

    PubMed

    Skeppström, K; Wåhlin, E

    2015-11-01

    Long-term measurements of thoron progeny concentrations (equilibrium-equivalent thoron concentration) have been carried out in Swedish dwellings with the aim of investigating if thoron and its progeny pose a health risk. Measurements were performed in 93 houses and 25 apartments. In addition to thoron progeny concentration, thoron gas concentration near the wall surface, ambient dose equivalent rate of gamma radiation and radon gas concentration were also measured. The results show that the mean value of thoron progeny was 2.2 Bq m(-3) in houses and 1.6 Bq m(-3) in apartments. Ten per cent of the dwellings (both houses and apartments) had thoron progeny concentrations exceeding 10 Bq m(-3). Thoron progeny concentration is not significantly different in dwellings built of alum shale-based aerated concrete ('blue concrete') than dwellings built of other construction materials. For the dwellings in this study (not representative of the Swedish population), the mean dose estimated due to exposure to thoron was found to be 0.4 mSv y(-1). © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. 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.

  6. 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.

  7. Indoor radon and lung cancer in the radium dial workers

    SciTech Connect

    Neuberger, J.S.; Rundo, J.

    1996-12-31

    Internally deposited radium has long been known to have tumorigenic effects in the form of sarcomas of the bone and carcinomas of the paranasal sinuses and mastoid air cells. However, the radium dial workers were also exposed to radiation hazards other than that occurring from ingestion of the radium paint, viz., external gamma radiation and elevated concentrations of airborne radon. The uranium miners were also exposed to high concentrations of radon in the 1950s and later, and numerous cases of lung cancer have occurred in that population. However, unlike the atmosphere in the uranium mines, the air in the dial painting plants was probably rather clean and perhaps not much different from the air in many houses. In view of the current concern over the possibility of lung cancer fin the general population being caused by radon (progeny) in houses, it is important to examine the mortality due to this usually fatal disease in the dial workers and to attempt to relate it to their exposure to radon, to the extent that this is possible.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. 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.

  14. Subnormal expression of cell-mediated and humoral immune responses in progeny disposed toward a high incidence of tumors after in utero exposure to benzo(a)pyrene

    SciTech Connect

    Urso, P.; Gengozian, N.

    1984-01-01

    Pregnant mice were exposed to 150 ..mu..g benzol(a)pyrene (BaP) per gram of body weight during fetogenesis (d 11-17 of gestation) and the progeny were assayed for humoral and cell mediated immune responses at different time intervals after birth. Immature offspring (1-4 wk) were severely suppressed in their ability to produce antibody (plaque-) forming cells (PFC) against sheep red blood cells (SRBC) and in the ability of their lymphocytes to undergo a mixed lymphocyte response (MLR). Lymphocytes from these progeny showed a moderate to weak capacity to inhabit production of colony-forming units (CFU) in host spleens following transfer with semiallogeneic bone marrow (BM) cells into lethally x-irradiated recipients syngeneic to the BM (in vivo graft-versus-host response, GVHR). A severe and sustained suppression in the MLR and the PFC response occurred from the fifth month up to 18 mo. The in vivo GVHR, also subnormal later in life, was not as severely suppressed as the other two parameters. Tumor incidence in the BP-exposed progeny was 8- to 10-fold higher than in those encountering corn oil alone from 18 to 24 mo of age. These data show that in utero exposure to the chemical carcinogen BaP alters development of components needed for establishing competent hemoral and cell-mediated functions of the immune apparatus and leads to severe and sustained postnatal suppression of the defense mechanism. The immunodeficiency exhibited, particularly in the T-cell compartment (MLR, GVHR), before and during the increase in tumor frequency, may provide a favorable environment for the growth of nascent neoplasms induced by BaP. 30 references, 4 figures, 2 tables.

  15. 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.

  16. 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.

  17. 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

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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

  3. Radon concentrations in residential housing in Hiroshima and Nagasaki

    SciTech Connect

    Yonehara, Hidenori; Aoyama, Takashi; Radford, E.P.

    1995-05-01

    A measurement of indoor radon ({sup 222}Rn) concentrations in Hiroshima and Nagasaki was carried out to assess the variability of exposure expected among atomic bomb survivors. Two hundred dwellings, mostly belonging to members of the fixed cohort of atomic bomb survivors under study by the Radiation Effects Research Foundations, were selected for this measurement. The geometric mean values of the radon concentrations for 100 dwellings in Hiroshima and 99 dwellings in Nagasaki measured by Track-Etcho Type SF detectors were 56.8 Bq m{sup {minus}3} and 28.5 Bq m{sup {minus}3}, respectively. No statistically significant difference was observed between lung cancer mortalities in the low-dose range in the two cities. However, apparent values of the mortality rate for low dose range in Hiroshima are consistently greater than those in Nagasaki. The exposure to radon and its progeny and the atomic bomb radiation effect might have some cooperative effects on the lung cancer incidence.

  4. 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.

  5. 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.

  6. 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.

  7. 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

  8. 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.

  9. 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.

  10. Radon in outdoor air in Nevada

    SciTech Connect

    Price, J.G.; Rigby, J.G.; Christensen, L.

    1994-04-01

    Measurements of radon at 50 sites with varying geology indicate that outdoor air in Nevada is comparable to that measured nationwide by Hopper et al. The state-wide median of 15 Bq m{sup -3} (0.4 pCi L{sup -1}) is essentially the same as the nationwide median. The range is considerable: from 2.6-52 Bq m{sup -3} (0.07-1.40 pCi L{sup -1}). Variations in these measurements can generally be correlated with different concentrations of radon in soils and uranium and its progeny in rocks. Silica-rich igneous rocks (rhyolites and granites) appear to be the main sources of high levels of radon in outdoor air in Nevada. Concentrations of radon in outdoor air generally correlate with levels of radon in soil gas. Measurements taken from heights of 0.5, 1.0, and 2.0 m above the ground suggest that radon in outdoor air reflects the local geology throughout this range of heights. Towns for which >20% of the homes have indoor-air radon concentrations >48 Bq m{sup -3} (4 pCi L{sup -1}) generally have relatively high soil-gas radon, relatively high outdoor-air radon, or both. 16 refs., 4 figs., 1 tab.

  11. Radon in outdoor air in Nevada.

    PubMed

    Price, J G; Rigby, J G; Christensen, L; Hess, R; LaPointe, D D; Ramelli, A R; Desilets, M; Hopper, R D; Kluesner, T; Marshall, S

    1994-04-01

    Measurements of radon at 50 sites with varying geology indicate that outdoor air in Nevada is comparable to that measured nationwide by Hopper et al. (1991). The statewide median of 15 Bq m-3 (0.4 pCi L-1) is essentially the same as the nationwide median. The range is considerable: from 2.6-52 Bq m-3 (0.07-1.40 pCi L-1). Variations in these measurements can generally be correlated with different concentrations of radon in soils and uranium and its progeny in rocks. Silica-rich igneous rocks (rhyolites and granites) appear to be the main sources of high levels of radon in outdoor air in Nevada. Concentrations of radon in outdoor air generally correlate with levels of radon in soil gas. Measurements taken from heights of 0.5, 1.0, and 2.0 m above the ground suggest that radon in outdoor air reflects the local geology throughout this range of heights. Towns for which > 20% of the homes have indoor-air radon concentrations > 48 Bq m-3 (4 pCi L-1) generally have relatively high soil-gas radon, relatively high outdoor-air radon, or both.

  12. [The status of the progeny of male rats subjected to low-dose external gamma irradiation exposure].

    PubMed

    Ovcharenko, E P; Kononenko, V V; Galian, S P; Vernidub, I V; Topchiĭ, I G

    1996-01-01

    In studies on 120 mature males of Wistar rats and 252 female rats of the same line, 20-day-old fetuses and 974 young rats of the first generation, anomalies of antenatal and postnatal development were found after exposure of spermatids and spermatozoa to gamma-radiation in doses 0.25-1.0 Gy. After exposure of male rats to radiation in dose 0.25 Gy, reliable delay of pelvic bone ossification was observed as compared to the control.

  13. (Radon: Chemical and physical processes associated with its distribution)

    SciTech Connect

    Castleman, A.W. Jr.

    1988-08-30

    This constitutes studies designed to provide data for assessing the mechanisms governing the distribution, fate and pathways of entry into biological systems, as well as the ultimate hazards, associated with radon progeny and their secondary reaction products. The chemical and physical state of radon progeny are expected to influence their mobility and reactivity, and mechanisms of transport and entry into biological systems since these depend on processes such as attachment to and/or incorporation with aerosol particles. There is evidence that an appreciable fraction of the progeny are ionized and this program addresses the clustering, growth, and subsequent chemical conversion of these associated species. 2 refs.

  14. 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.

  15. Measurements of radon concentrations in the lunar atmosphere

    NASA Technical Reports Server (NTRS)

    Brodzinski, R. L.; Jackson, P. O.; Langford, J. C.

    1977-01-01

    The radon concentrations in the lunar atmosphere were determined by measuring the Po-210 progeny activity in artifacts returned from the moon. Experiments performed on a section of the polished aluminum strut from Surveyor 3 and data obtained from the Apollo 16 Cosmic Ray Detector Experiment Teflon thermal shield are compared with other values of the lunar radon concentration obtained at different times and different locations and by various techniques. Possible sources and release mechanisms compatible with all of the data are discussed. An experimental procedure to determine the relative retention coefficients of various types of material for radon progeny in a simulated lunar environment is described. The results of several experiments are given, and their effect on lunar radon progeny measurements is discussed. An analytical procedure is given for the analysis of a Teflon matrix for trace constituents.

  16. Problems with Estimating Annual Mean Indoor Radon Concentrations

    SciTech Connect

    Marusiakova, Miriam; Hulka, Jiri

    2010-09-30

    Radon and its progeny in dwellings is responsible for the majority of the total radiation dose among the general population. The indoor radon concentration varies considerably during the daytime, individual days, seasons and even years. It is affected by many factors such as ventilation, soil concentration, quality of house insulation and others.The annual mean value of the radon concentration in buildings is important in order to estimate the effective dose to inhabitants. However, it is not always possible to perform radon measurements over a period of one year. Thus estimates based on short-term continuous measurements are suggested.We analyse hourly radon measurements obtained from one uninhabited rural house in Teleci in the Czech Republic. We study the behaviour of the radon concentration with time and its relationship to meteorological variables such as outdoor temperature, wind speed or pressure. Further we discuss various estimates of the annual mean radon concentration and their properties.

  17. Impact of radon gas concentration in the aerosoles profile

    SciTech Connect

    Lukaj, Edmond Vila, Floran; Mandija, Florian

    2016-03-25

    Radon gases relased from building materials and from earth surface are the major responsibility of air ionization. Radon nuclear decay can produce an alpha particle with high energy and Radon progeny. This particle and gamma rays can deliver particles in the air and produce ions with different polarities. This ions, because of induced electric charge, can attach with air aerosols and charge them with their electric charge. The charged aerosols can interact with the other aerosols and ions. Because of this exchange, the air conductivity and the aerosol profiles will change dependently by Radon gas concentration and gamma radiation. Observations show an increase in concentration of Radon during the night, and a decrease during the daylight time. The Radon gas concentration changed hour by hour can induce aerosol profile to change. This dependency between the aerosol profiles and the Radon gas concentrations is discussed.

  18. Problems with Estimating Annual Mean Indoor Radon Concentrations

    NASA Astrophysics Data System (ADS)

    Marušiaková, Miriam; Hůlka, Jińrí

    2010-09-01

    Radon and its progeny in dwellings is responsible for the majority of the total radiation dose among the general population. The indoor radon concentration varies considerably during the daytime, individual days, seasons and even years. It is affected by many factors such as ventilation, soil concentration, quality of house insulation and others. The annual mean value of the radon concentration in buildings is important in order to estimate the effective dose to inhabitants. However, it is not always possible to perform radon measurements over a period of one year. Thus estimates based on short-term continuous measurements are suggested. We analyse hourly radon measurements obtained from one uninhabited rural house in Telecí in the Czech Republic. We study the behaviour of the radon concentration with time and its relationship to meteorological variables such as outdoor temperature, wind speed or pressure. Further we discuss various estimates of the annual mean radon concentration and their properties.

  19. 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.

  20. High-LET alpha-emitters: Radon, lung cancer and smoking

    SciTech Connect

    Fabrikant, J.I.

    1988-11-01

    The National Academy of Sciences BEIR IV Report deals with the health effects in human populations exposed to internally-deposited alpha-emitting radionuclides and their decay products. Quantitative risk estimates for cancer induction are derived, mainly from analyses of epidemiological data. The Report addresses the health outcomes of exposure to radon and its daughters, primarily lung cancer risks of worker exposure to radon progeny in underground mines and in the general public in indoor domestic environments. An excess relative risk model of lung cancer mortality and exposure to radon progeny is developed; this models the excess risk per Working Level Month in terms of time intervals prior to an attained age, and is dependent on time-since-exposure and age at risk. Risk projections are presented and cover exposure situations of current public health concern. For example, lifetime exposure to 1 WLM y/sup /minus/1/ is estimated to increase the number of deaths due to lung cancer by a factor of about 1.5 over the current rate for both males and females in a population having the current prevalence of cigarette-smoking. Occupational exposure to 4 WLM y/sup /minus/1/ from ages 20 y to 40 y is projected to increase lung cancer deaths by a factor of 1.6 over the current rate of this age cohort in the general population. In all of these cases, most of the increased risk occurs to smokers for whom the risk is up to ten times greater than for non-smokers. 8 refs., 1 tab.

  1. 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.

  2. 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.

  3. 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.

  4. 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)

  5. 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)

  6. 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.

  7. Indoor radon concentrations in Taiwanese homes

    SciTech Connect

    Hung, I.F.; Yu, C.C.; Tung, C.J. ); Yang, Y.C.; Chou, K.D. )

    1994-10-01

    Many air pollutants may be present in the indoor environment. Commonly reported pollutants are carbon monoxide, nitrogen dioxide, volatile organic compounds, radon and its progeny, asbestos fibers and airborne particles. Among these indoor pollutants, radon and its progeny have been known to increase the risk of lung cancer in the U.S. Various studies also found in general higher concentrations of air pollutants in the indoor environment. It is a serious concern to us because of the long periods of time we spend indoors. In this study, the alpha-track radon monitor was used in the screening of higher risk buildings in Taipei and Hsinchu city. None of the homes in the 32 buildings surveyed in these cities had air concentrations of radon exceeding the action level of 4 pCi/l recommended by the U.S. Environmental Protection Agency. Different sources to indoor radon concentrations are the underlying soil, building materials, outdoor air, water and gaseous fuels. Ventilation of the homes and seasonal variations are major factors of higher radon concentrations. 16 refs., 2 figs., 3 tabs.

  8. 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.

  9. 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.

  10. Air conditioning impact on the dynamics of radon and its daughters concentration.

    PubMed

    Kozak, Krzysztof; Grządziel, Dominik; Połednik, Bernard; Mazur, Jadwiga; Dudzińska, Marzenna R; Mroczek, Mariusz

    2014-12-01

    Radon and its decay products are harmful pollutants present in indoor air and are responsible for the majority of the effective dose due to ionising radiation that people are naturally exposed to. The paper presents the results of the series of measurements of radon and its progeny (in unattached and attached fractions) as well as indoor air parameters: temperature, relative humidity, number and mass concentrations of fine aerosol particles. The measurements were carried out in the auditorium (lecture hall), which is an indoor air quality laboratory, in controlled conditions during two periods of time: when air conditioning (AC) was switched off (unoccupied auditorium) and when it was switched on (auditorium in normal use). The significant influence of AC and of students' presence on the dynamics of radon and its progeny was confirmed. A decrease in the mean value of radon and its attached progeny was found when AC was working. The mean value of radon equilibrium factor F was also lower when AC was working (0.49) than when it was off (0.61). The linear correlations were found between attached radon progeny concentration and particle number and mass concentration only when the AC was switched off. This research is being conducted with the aim to study the variability of radon equilibrium factor F which is essential to determine the effective dose due to radon and its progeny inhalation. © The Author 2013. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. 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.

  12. 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

  13. 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)

  14. Human Lung Cancer Risks from Radon – Part I - Influence from Bystander Effects - A Microdose Analysis

    PubMed Central

    Leonard, Bobby E.; Thompson, Richard E.; Beecher, Georgia C.

    2010-01-01

    Since the publication of the BEIR VI report in 1999 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, at low domestic and workplace radon levels, in particular the Bystander Effect (BE) and the Adaptive Response radio-protection (AR). We analyzed the microbeam and broadbeam alpha particle data of Miller et al. (1995, 1999), Zhou et al. (2001, 2003, 2004), Nagasawa and Little (1999, 2002), Hei et al. (1999), Sawant et al. (2001a) and found that the shape of the cellular response to alphas is relatively independent of cell species and LET of the alphas. The same alpha particle traversal dose response behavior should be true for human lung tissue exposure to radon progeny alpha particles. In the Bystander Damage Region of the alpha particle response, there is a variation of RBE from about 10 to 35. There is a transition region between the Bystander Damage Region and Direct Damage Region of between one and two microdose alpha particle traversals indicating that perhaps two alpha particle “hits” are necessary to produce the direct damage. Extrapolation of underground miners lung cancer risks to human risks at domestic and workplace levels may not be valid. PMID:21731539

  15. 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

  16. 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

  17. 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

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. An absolute radon 222 activity measurement system at LNE-LNHB.

    PubMed

    Sabot, B; Pierre, S; Cassette, P

    2016-12-01

    A good metrological traceability of radon and progenies is necessary to accurately measure the radon concentration. In 1995, at the LNE-LNHB, J.L. Picolo developed a reference method using a defined-solid-angle (DSA) alpha spectrometer to measure a frozen radon source. With this method it was possible to measure radon standards with a relative standard uncertainty of 0.5%. This paper presents the design and the characterization of a new upgraded measurement system; all parameters and their uncertainties are discussed. This new system allows the measurement of radon sources from 100Bq to 4MBq with a relative standard uncertainty of 0.3%.

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  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. 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.

  12. Radon induced hyperplasia: effective adaptation reducing the local doses in the bronchial epithelium.

    PubMed

    Madas, Balázs G

    2016-09-01

    There is experimental and histological evidence that chronic irritation and cell death may cause hyperplasia in the exposed tissue. As the heterogeneous deposition of inhaled radon progeny results in high local doses at the peak of the bronchial bifurcations, it was proposed earlier that hyperplasia occurs in these deposition hot spots upon chronic radon exposure. The objective of the present study is to quantify how the induction of basal cell hyperplasia modulates the microdosimetric consequences of a given radon exposure. For this purpose, computational epithelium models were constructed with spherical cell nuclei of six different cell types based on histological data. Basal cell hyperplasia was modelled by epithelium models with additional basal cells and increased epithelium thickness. Microdosimetry for alpha-particles was performed by an own-developed Monte-Carlo code. Results show that the average tissue dose, and the average hit number and dose of basal cells decrease by the increase of the measure of hyperplasia. Hit and dose distribution reveal that the induction of hyperplasia may result in a basal cell pool which is shielded from alpha-radiation. It highlights that the exposure history affects the microdosimetric consequences of a present exposure, while the biological and health effects may also depend on previous exposures. The induction of hyperplasia can be considered as a radioadaptive response at the tissue level. Such an adaptation of the tissue challenges the validity of the application of the dose and dose rate effectiveness factor from a mechanistic point of view. As the location of radiosensitive target cells may change due to previous exposures, dosimetry models considering the tissue geometry characteristic of normal conditions may be inappropriate for dose estimation in case of protracted exposures. As internal exposures are frequently chronic, such changes in tissue geometry may be highly relevant for other incorporated radionuclides.

  13. 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.

  14. 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

  15. 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.

  16. A comparative study of the indoor radon level with the radon exhalation rate from soil in Alexandria city.

    PubMed

    Abd El-Zaher, Mohamed

    2013-05-01

    The assessment of the radiological risk related to the inhalation of radon and radon its progeny is based mainly on the integrated measurement of radon in both indoor and outdoor environments. The exhalation of radon from the earth's crust and building materials forms the main source of radon in the indoor environment. This study has been undertaken for the purpose of health risk assessment. In this comparative study, the indoor radon level, radium content, radon exhalation rate and concentration of soil radon are measured using the Can Technique. Soil samples were collected simultaneously from different geological formations of the same area for laboratory measurement of the radon exhalation rate. The radon exhalation rate was measured in the laboratory using LR-115 type II plastic track detectors. The indoor radon concentrations in this study area were found to vary from 44±9 to 132±31 Bq m(-3) with an average of 72±29 Bq m(-3). The seasonal variations of the indoor radon reveal the maximum values in the winter and in summer in different dwellings of Alexandria city. The annual effective dose varies from 0.75 to 2.2 mSv with an average value of 1.34 mSv. The radon exhalation rate was found to vary in the ranges 8.31-233.70×10(-3) Bq kg(-1) h(-1), 0.48-15.37 Bq m(-2) h(-1) with an average 47.97×10(-3) Bq kg(-1) h(-1), (3.14 Bq m(-2) h(-1)). The radium content in soil varies from 3.14 to 39.60 Bq kg(-1) with an average of 11.55 Bq kg(-1). The significance of this study is discussed in details from the point of view of radiation protection.

  17. 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.

  18. Radon exhalation rates from some soil samples of Kharar, Punjab

    SciTech Connect

    Mehta, Vimal; Singh, Tejinder Pal; Chauhan, R. P.; Mudahar, G. S.

    2015-08-28

    Radon and its progeny are major contributors in the radiation dose received by general population of the world. Because radon is a noble gas, a large portion of it is free to migrate away from radium. The primary sources of radon in the houses are soils and rocks source emanations, emanation from building materials, and entry of radon into a structure from outdoor air. Keeping this in mind the study of radon exhalation rate from some soil samples of the Kharar, Punjab has been carried out using Can Technique. The equilibrium radon concentration in various soil samples of Kharar area of district Mohali varied from 12.7 Bqm{sup −3} to 82.9 Bqm{sup −3} with an average of 37.5 ± 27.0 Bqm{sup −3}. The radon mass exhalation rates from the soil samples varied from 0.45 to 2.9 mBq/kg/h with an average of 1.4 ± 0.9 mBq/kg/h and radon surface exhalation rates varied from 10.4 to 67.2 mBq/m{sup 2}/h with an average of 30.6 ± 21.8 mBq/m{sup 2}/h. The radon mass and surface exhalation rates of the soil samples of Kharar, Punjab were lower than that of the world wide average.

  19. 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.

  20. Variability of radon and thoron equilibrium factors in indoor environment of Garhwal Himalaya.

    PubMed

    Prasad, Mukesh; Rawat, Mukesh; Dangwal, Anoop; Kandari, Tushar; Gusain, G S; Mishra, Rosaline; Ramola, R C

    2016-01-01

    The measurements of radon, thoron and their progeny concentrations have been carried out in the dwellings of Uttarkashi and Tehri districts of Garhwal Himalaya, India using LR-115 detector based pin-hole dosimeter and DRPS/DTPS techniques. The equilibrium factors for radon, thoron and their progeny were calculated by using the values measured with these techniques. The average values of equilibrium factor between radon and its progeny have been found to be 0.44, 0.39, 0.39 and 0.28 for rainy, autumn, winter and summer seasons, respectively. For thoron and its progeny, the average values of equilibrium factor have been found to be 0.04, 0.04, 0.04 and 0.03 for rainy, autumn, winter and summer seasons, respectively. The equilibrium factor between radon and its progeny has been found to be dependent on the seasonal changes. However, the equilibrium factor for thoron and progeny has been found to be same for rainy, autumn and winter seasons but slightly different for summer season. The annual average equilibrium factors for radon and thoron have been found to vary from 0.23 to 0.80 with an average of 0.42 and from 0.01 to 0.29 with an average of 0.07, respectively. The detailed discussion of the measurement techniques and the explanation for the results obtained is given in the paper. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Analysis of radon reduction and ventilation systems in uranium mines in China.

    PubMed

    Hu, Peng-hua; Li, Xian-jie

    2012-09-01

    Mine ventilation is the most important way of reducing radon in uranium mines. At present, the radon and radon progeny levels in Chinese uranium mines where the cut and fill stoping method is used are 3-5 times higher than those in foreign uranium mines, as there is not much difference in the investments for ventilation protection between Chinese uranium mines and international advanced uranium mines with compaction methodology. In this paper, through the analysis of radon reduction and ventilation systems in Chinese uranium mines and the comparison of advantages and disadvantages between a variety of ventilation systems in terms of radon control, the authors try to illustrate the reasons for the higher radon and radon progeny levels in Chinese uranium mines and put forward some problems in three areas, namely the theory of radon control and ventilation systems, radon reduction ventilation measures and ventilation management. For these problems, this paper puts forward some proposals regarding some aspects, such as strengthening scrutiny, verifying and monitoring the practical situation, making clear ventilation plans, strictly following the mining sequence, promoting training of ventilation staff, enhancing ventilation system management, developing radon reduction ventilation technology, purchasing ventilation equipment as soon as possible in the future, and so on.

  2. 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.

  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. 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

  5. Influence of air flow on the behavior of thoron and its progeny in a traditional Japanese house

    SciTech Connect

    Ma, Jizeng; Doi, Masahiro; Kobayashi, Sadayoshi

    1997-01-01

    Air flow influence on the spatial distribution of thoron ({sup 220}Rn) concentration in a typical Japanese traditional house was investigated at various indoor air flow levels. The effect of air flow on the behavior of both thoron and radon progeny were examined simultaneously. Measurements were carried out by using two types of passive monitors, the radon-thoron discriminative monitor and the Radtrak monitor. Thoron and radon progeny were measured by filter grab sampling with ZnS scintillation counting. Under static condition, a horizontal distribution with greatly varied thoron concentrations was found as reported by previous studies. Under turbulent conditions, thoron concentrations in the middle of the room increased and the concentration gradient of thoron gas became lower. An obvious vertical distribution of thoron was also observed. Prominent diurnal variation of radon progeny concentrations was observed whereas that of thoron progeny concentrations was not. Concentration of thoron progeny changed little at different air flow levels, although the thoron gas level at the middle of the room varied significantly. The influence of air flows on detection efficiencies of the two types of thoron monitors were also checked. The mechanism of behavioral change of thoron and its progeny in turbulent atmosphere is discussed. 18 refs., 7 figs.

  6. 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.

  7. 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....

  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 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

  10. Influence of indoor air conditions on radon concentration in a detached house.

    PubMed

    Akbari, Keramatollah; Mahmoudi, Jafar; Ghanbari, Mahdi

    2013-02-01

    Radon is released from soil and building materials and can accumulate in residential buildings. Breathing radon and radon progeny for extended periods hazardous to health and can lead to lung cancer. Indoor air conditions and ventilation systems strongly influence indoor radon concentrations. This paper focuses on effects of air change rate, indoor temperature and relative humidity on indoor radon concentrations in a one family detached house in Stockholm, Sweden. In this study a heat recovery ventilation system unit was used to control the ventilation rate and a continuous radon monitor (CRM) was used to measure radon levels. FLUENT, a computational fluid dynamics (CFD) software package was used to simulate radon entry into the building and air change rate, indoor temperature and relative humidity effects using a numerical approach. The results from analytical solution, measurements and numerical simulations showed that air change rate, indoor temperature and moisture had significant effects on indoor radon concentration. Increasing air change rate reduces radon level and for a specific air change rate (in this work Ach = 0.5) there was a range of temperature and relative humidity that minimized radon levels. In this case study minimum radon levels were obtained at temperatures between 20 and 22 °C and a relative humidity of 50-60%.

  11. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. Radon measurements with a PIN photodiode.

    PubMed

    Martín-Martín, A; Gutiérrez-Villanueva, J L; Muñoz, J M; García-Talavera, M; Adamiec, G; Iñiguez, M P

    2006-01-01

    Silicon photodiodes are well suited to detect alphas coming from different sources as neutron reactions or radon daughters. In this work a radon in air detecting device, using an 18x18 mm silicon PIN photodiode is studied. The ionized airborne decay products formed during radon diffusion were focused by an accelerating high voltage to the PIN surface. Several conducting rings were disposed inside a cylindrical PVC vessel in such a way that they reproduced the electric field created by a punctual charge located behind PIN position. Alpha spectra coming from the neutral and ionized species deposited on the PIN surface, dominated by 218Po and 214Po progeny peaks, were recorded for varying conditions. Those include radon concentration from a Pylon source, high voltage (thousands of volts) and PIN inverse bias voltage. Different parameters such as temperature and humidity were also registered during data acquisition. The increase in the particle collection efficiency with respect to zero electric field was compared with the corresponding to a parallel plates configuration. A discussion is made in terms of the most appropriate voltages for different radon concentrations.

  17. 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.

  18. 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.

  19. 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

  20. 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.

  1. 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.

  2. 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

  3. Daily and seasonal variations of radon activity measured in Mystery Cave

    SciTech Connect

    Lively, R.S. ); Krafthefer, B. ); Netherton, W. )

    1993-03-01

    Mystery Cave, southeastern Minnesota, is the site of an ongoing study of how radon and radon progeny are affected by meteorological changes in and about the dave. Data on radon, radon progeny, temperature, relative humidity, barometric pressure, wind speed and direction, and rainfall are collected at 4-hour intervals at different locations within and just outside the cave. During winter months, average ambient radon levels ranged from 5 to 200 pCi/L. Transient levels above 500 pCi/L tended to correlate with failing barometric pressure, but not with the magnitude of [Delta]P. In summer, average ambient radon increased to around 300 pCi/L with short-term levels exceeding 500 pCi/L. Fluctuations related to temperature were also noted. Radon progeny generally correlate with radon and both showed rates of change faster than ingrowth or decay. In addition to the time variations in the radon activity levels, pulses were observed between monitoring locations. The probable correlation of radon-activity transport with aboveground meteorological changes and preliminary data on cave airflow is being studied. Previous grab sampling with Lucas cells and integrating alpha-track devices did not show either the 10- to 100-fold daily fluctuations or the pulses. As more continuous data become available, it is increasingly evident that radon fluctuates on time scales that range from hours to years, in response to conditions both inside and outside the cave system. Funding for this project was approved by the Minnesota legislature ML 1991, Chapter 264, Art. 1, Sec. 14, subd. 3 (I) as recommended by the Legislative Commission on Minnesota Resources from the Minnesota Future Resources Fund.

  4. 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 ...

  5. 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.

  6. 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.

  7. 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

  8. Uncertainty analysis of relative biological effectiveness of alpha-radiation for human lung exposure.

    PubMed

    Yarmoshenko, Ilia; Kirdin, Ivan; Zhukovsky, Michael

    2006-04-01

    Assessment of relative biological effectiveness (RBE) for a radiation in the cases of inhalation of radon progeny and incorporation of plutonium in lung is based on simulation of lung cancer radiation risk for alpha and external reference types of radiation. Specific radiation risk models developed on the results of direct epidemiological studies are used for simulation. These include published risk models for nuclear workers of the Mayak facilities in the former Soviet Union exposed to incorporated plutonium (Kreisheimer et al., 2003; Gilbert et al., 2004) and underground miners exposed to radon progenies (BEIR VI, 1999). Additionally, a lung cancer risk model is developed for a case of population indoor radon exposure. Lung cancer risk related to external exposure is estimated using the risk model developed for the analyses of Japanese atomic bomb survivors (Preston et al., 2003). Uncertainties of risk models parameters are considered and the uncertainties of RBE are estimated using the results of lifetime lung cancer risk simulation, which is done implementing a Monte Carlo approach. Estimated median value of RBE in case of indoor radon exposure is 1.5 with 90% range 0.4-7. In the case of the two models developed by BEIR VI for lung cancer risk due to radon exposure in underground miners, the median values of RBE are 2.1 and 4.4 with 90% ranges 0.3-17 and 0.7-45, respectively. The two different models for lung cancer risk related to plutonium exposure resulted in close estimates of RBE: median value of 12 and 13 with 90% range 4-104 and 4-136, respectively.

  9. Measurement uncertainties in whole body counting and radon progeny.

    PubMed

    Valakis, Stratos T; Pallada, Stavroula; Kalef-Ezra, John A

    2014-07-01

    Measurement uncertainty is an important quality index in gamma spectrometry related to the level of bias and precision involved in the measuring procedure. Quality control measurements during the commissioning of a 16-input whole body counter showed substantial deviations between the experimentally determined precision and the theoretical estimation, indicating either equipment malfunction or lack of reproducibility of the experimental setup. In this study, the role of the magnitude and variability of airborne background radiation present in the counting room and the human body in the deterioration of the precision of counters employing NaI(Tl) detectors was investigated. Correction methods and actions based on case-specific background features were developed and applied. The experimental observations were benchmarked using a mathematical model of the counter. The efficacy of the developed methods was tested by measurements, and updated precision values were obtained. Quasi-equilibrium between the gamma-emitters Bi and Pb in the counting room and the human body is a prerequisite for accurate direct low-level radioactivity measurements in the human body.

  10. Age-dependent lung dosimetry of radon progeny

    SciTech Connect

    Hofmann, W.; Martonen, T.B.; Menache, M.G.

    1988-02-01

    Two morphometric models differing in the tracheobronchial region, were compared in the present paper: Model 1 is based on the adult morphology of Weibel, assuming that all bronchial airways grow in equal proportion; while Model 2 adopts the adult structure proposed by Yeh and Schum, using measured airway dimensions in the right upper lobe as a function of age. Tidal volume and respiratory frequency also vary with age: while the breathing frequency decreases with rising age, tidal volume increases. Radiation doses in each bronchial airway generation were computed for the deep lying basal cells as well as for the more uniformly distributed serous (SMGS) cells, which are currently assumed to be the progenitor cells for bronchial carcinomas. Radiation doses to both target cells were significantly higher in the newborn than in the adult, for all simulated breathing patterns, showing the highest relative increase in upper bronchial airways. Comparing both tracheobronchial growth models, Model 1 predicts higher doses at early ages, but produced lower doses in the adult lung.

  11. Activation of oncogenes by radon progeny and x-rays

    SciTech Connect

    Ling, C.C.

    1990-01-01

    The overall goal of this proposal is to study the carcinogenic effect of both high and low LET radiation at the molecular level, utilizing techniques developed in molecular biology, cancer cell biology and radiation biology. The underlying assumption is that malignant transformation of normal cells is a multistep process requiring two or more molecular events in the genomic DNA. These events are most likely the activation of proto-oncogenes, or the inactivation of tumor suppressor genes. We hypothesize that radiation may induce such events in one or more steps of the multistep process. We will use in vitro models of transformation that reproduce the stepwise progression of normal cells towards the transformed phenotype and ask whether radiation can provide the necessary activating function at discrete steps along this path. Our strategy involves transfecting into normal primary cells a variety of cloned oncogenes that are known to supply only some of the functions necessary for full transformation. These partially transformed'' cells will be the targets for irradiation by x-rays and alpha particles. The results will provide the basis for assessing the ability of ionizing radiation to activate oncogenic functions that complement'' the oncogene already present in the transfected ells and produce the fully transformed phenotype. 121 refs.

  12. Activation of oncogenes by radon progeny and x-rays

    SciTech Connect

    Ling, C.C.

    1990-01-01

    The overall goal of this proposal is to study the carcinogenic effect of both high and low LET radiation at the molecular level, utilizing techniques developed in molecular biology, cancer cell biology and radiation biology. The underlying assumption is that malignant transformation of normal cells is a multistep process requiring two or more molecular events in the genomic DNA. We hypothesize that radiation may induce such events in one or more steps of the multistep process. We will use in vitro models of transformation that reproduce the stepwise progression of normal cells toward the transformed phenotype and ask whether radiation can provide the necessary activating function at discrete steps along this path. Our strategy involves transfecting into normal primary cells a variety of cloned oncogenes that are known to supply only some of the functions necessary for full transformation. These partially transformed'' cells will be the targets for irradiation by x-rays and alpha particles. The results will provide the basis for assessing the ability of ionizing radiation to activate oncogenic functions that complement'' the oncogene already present in the transfected cells and produce the fully transformed phenotype. Progress is described. 121 refs.

  13. 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

  14. 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.

  15. 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.

  16. Thoron ( 220Rn) progeny reduction by an air cleaner of the polarized media filter type

    NASA Astrophysics Data System (ADS)

    Bigu, J.

    1993-02-01

    The effect of an air cleaner on 220Rn progeny atmospheres has been studied in a Radon/Thoron Test Facility (RTTF) of the walk-in type. The air cleaner consists basically of a fan and a special filter material sandwiched between two metal screens, to which an electric field is applied. The filter is of the polarized media type and uses fibreglass as material. The fan and filter system are housed in a metal case. Air is drawn from the back of the case by means of the fan and forced through the "electrical" filter where removal of the 220Rn progeny occurs. Radon-220 progeny "depleted" air is discharged at the top of the device. Tests were conducted in 220Rn/ 220Rn progeny atmospheres when the air cleaner was operating, and when it was turned off. Very pronounced effects were observed during the operation of the device, namely: a dramatic decrease in the 220Rn progeny concentrations and the total aerosol concentration, as well as a large increase in the 220Rn progeny unattached fractions and the plate-out of these radionuclides on the walls of the RTTF. The air cleaner has potential in industrial applications, which should be explored.

  17. Lung cancer from radon: a two-stage model analysis of the WISMUT Cohort, 1955-1998.

    PubMed

    van Dillen, Teun; Dekkers, Fieke; Bijwaard, Harmen; Kreuzer, Michaela; Grosche, Bernd

    2011-01-01

    A biologically based two-stage carcinogenesis model is applied to epidemiological data for lung cancer mortality in a large uranium miner cohort of the WISMUT company (Germany). To date, this is the largest uranium miner cohort analyzed by a mechanistic model, comprising 35,084 workers among whom 461 died from lung cancer in the follow-up period 1955-1998. It comprises only workers who were first employed between 1955 and 1989 and contains information on annual exposures to radon progeny. We fitted the model's free parameters, including the average growth time of one malignant cell into a lethal tumor. This lag time has an extraordinary value of 13 to 14 years, larger than that previously used or found in miner studies. Even though cohort-wide information on smoking habits is limited and the calendar-year dependence of tobacco smoke exposure was only implicitly accounted for by a birth cohort effect, we find good agreement between the modeled (expected) and empirical (observed) lung cancer mortality. Model calculations of excess relative lung cancer death risk agree well with those from the descriptive, BEIR VI-type exposure-age-concentration model for WISMUT miners. The large variety of exposure profiles in the cohort leads to a well-determined mechanistic model that in principle allows for an extrapolation from occupational to indoor radon exposure.

  18. 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

  19. STUDY ON RADON CONCENTRATION AT THE WORK PLACES OF MYSURU, BENGALURU AND KOLAR DISTRICTS OF KARNATAKA STATE, SOUTH INDIA.

    PubMed

    Ningappa, C; Hamsa, K S; Reddy, K Umesha; Niranjan, R S; Rangaswamy, D R; Sannappa, J

    2016-10-01

    Concentrations of radon, thoron and their progeny inside the working place depend on the activity of radionuclides in the soil, building materials, atmospheric conditions, construction of the building, type of work and ventilation condition. Radon is a radioactive noble gas, and it is emanated from (226)Ra present in earth crest and building material. Based on the type of work, construction of the building and ventilation condition, concentrations of radon, thoron and their progeny have been measured in 60 workplaces at 10 locations of Mysuru, Bengaluru and Kolar districts of Karnataka state using Solid-State Nuclear Track Detector technique. From the study, variations of radon, thoron and their progeny have been observed with the nature of work.

  20. 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

  1. 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 ...

  2. 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.

  3. Direct total body (214)Bi measurements and their implications for radon dose assessment.

    PubMed

    Kalef-Ezra, John A; Valakis, Stratos T

    2016-09-01

    Direct (214)Bi bioassays may elucidate some of the uncertainties related to the relationship between the ambient concentration of radon and its short-lived decay products and the corresponding radiation burdens of individual human subjects. Sequential total body (214)Bi activity measurements were carried out on a group of 67 healthy adult volunteers living in a region with moderate airborne radioactivity and conducting similar daily activities using a whole-body counter equipped with sixteen NaI(Tl) detectors. The total body (214)Bi activity in the studied subjects was related to gender, fat-free mass and the season of the year. Approximately 95% and 92% of the (214)Bi activity measured during the cold seasons of the year in men and women, respectively, was attributed to radon progeny inhalation. Following acute exposure to high airborne radioactivity over a short time period, the (214)Bi enhancement in a volunteer decreased exponentially with time post-exposure, with a half-time of about 40 min. Taking into account the anticipated low (214)Bi activity in the vast majority of individuals, and the uncertainties in (214)Bi biodistribution even during counting, accurate measurements can be obtained using high-sensitivity whole-body counters with almost geometrical invariant counting efficiency.

  4. Activity of radon (222Rn) in the lower atmospheric surface layer of a typical rural site in south India

    NASA Astrophysics Data System (ADS)

    Kumar, K. Charan; Prasad, T. Rajendra; Ratnam, M. Venkat; Nagaraja, Kamsali

    2016-10-01

    Analysis of one year measurements of in situ radon (222Rn) and its progenies along with surface air temperature, relative humidity and pressure near to the Earth's surface has been carried out for the first time at the National Atmospheric Research Laboratory (NARL, 13.5∘N and 79.2∘E) located in a rural site in Gadanki, south India. The dataset was analysed to understand the behaviour of radon in relation to the surface air temperature and relative humidity at a rural site. It was observed that over a period of the 24 hours in a day, the activity of radon and its progenies reaches a peak in the morning hours followed by a remarkable decrease in the afternoon hours. Relatively, a higher concentration of radon was observed at NARL during fair weather days, and this can be attributed to the presence of rocky hills and dense vegetation surrounding the site. The high negative correlation between surface air temperature and activity of radon ( R = - 0.70, on an annual scale) suggests that dynamical removal of radon due to increased vertical mixing is one of the most important controlling processes of the radon accumulation in the atmospheric surface layer. The annual averaged activity of radon was found to be 12.01±0.66 Bq m-3 and 4.25±0.18 Bq m-3 for its progenies, in the study period.

  5. Indoor-atmospheric radon-related radioactivity affected by a change of ventilation strategy.

    PubMed

    Kobayashi, Tsuneo

    2006-12-01

    The present author has kept observation for concentrations of atmospheric radon, radon progeny and thoron progeny for several years at the campus of Fukushima Medical University. Accidentally, in the midst of an observation term, i.e., February 2005, the facility management group of the university changed a strategy for the manner of ventilation, probably because of a recession: (I) tidy everyday ventilation of 7:30-24:00 into (II) shortened weekday ventilation of 8: 00-21 : 00 with weekend halts. This change of ventilation manner brought a clear alteration for the concentrations of radon-related natural radioactivity in indoor air. The present paper concerns an investigation of the effect of the ventilation strategy on the indoor-atmospheric radon-related radioactivity.

  6. 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.

  7. Radon concentrations in elementary schools in Kuwait.

    PubMed

    Maged, A F

    2006-03-01

    Measurements of indoor radon concentrations were performed in 25 classrooms in the capital city of Kuwait from September 2003 to March 2004 using track etch detectors. The investigation was focused on area, ventilation, windows, air conditioners, fans, and floor number. All the schools have nearly the same design. Mean indoor radon concentration was higher for case subjects (classrooms) than for control subjects (locations in inert gas, p < 0.001). The mean alpha dose equivalent rate for case subjects, 0.97 +/- 0.25 mSv y, was higher than the radiation dose equivalent rate value of control subjects, 0.43 +/- 0.11 mSv y. The average radon concentrations were found to be 16 +/- 4 Bq m for the first floor and 19 +/- 4.8 Bq m for the second floor after subtraction of the control. These values lead to average effective dose equivalent rates of 0.40 +/- 0.10 and 0.48 +/- 0.12 mSv y, respectively. The equilibrium factor between radon and its progeny was found to be 0.6 +/- 0.2.

  8. Estimate of the dose-increment due to outdoor exposure to gamma rays from uranium progeny deposited on the soil around a coal-fired power plant in Ajka Town, Hungary.

    PubMed

    Papp, Z; Dezsö, Z

    2003-06-01

    Brown coal unusually rich in uranium is burnt in a coal-fired power plant that lies inside the confines of a small industrial town named Ajka, Hungary, and has been operational since 1943. The 238U (226Ra) activity discharged to the atmosphere per unit electrical energy produced was about 330-400 GBq (GW y)(-1), which is 66-80 times more than that was estimated by UNSCEAR (1988) as a characteristic value for old type coal-fired power plants [5 GBq (GW y)(-1)]. The objective of this study was the experimentally established assessment of the artificial increment in the dose from external exposure to gamma rays of terrestrial radionuclides outdoors. Soil samples were collected in and near Ajka from 81 locations. The samples were investigated by Ge(Li) gamma spectrometry. Considerably elevated concentrations of uranium and its progeny have been measured in most of the samples that were collected near to the plant. Concentrations of 238U and 226Ra in the top (0-5 cm depth) layer of undisturbed soil at public areas inside town were 4.7 times higher, on average, than those in the uncontaminated deeper layers. Dose rate in air (air kerma) from external exposure to terrestrial gamma rays outdoors at a height of 1 m and effective doses were estimated from the measured activity concentrations using some relevant literature data. The estimated artificial increment in the dose rate in air was, on average, 32.8, 10.3, and 102.1 nGy h(-1) at public areas, vegetable gardens, and backyards, respectively. The mean artificial increment in the annual per caput effective dose from external exposure to terrestrial radionuclides outdoors is 21.8 microSv y(-1). The collective dose commitment per unit energy generated from outdoor exposure to the deposited uranium progeny is about 8.0-9.1 person Sv (GW y)(-1), which is 67-76 times more than that evaluated by UNSCEAR (1988) for a typical "old" coal-fired power plant [0.12 person Sv (GW y)(-1)]. Ajka is a suitable place for studying the

  9. 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)

  10. Controlling the Radon Threat Needn't Be Another Costly Nightmare.

    ERIC Educational Resources Information Center

    Freije, Matthew R.

    1989-01-01

    After a stud