Science.gov

Sample records for radon exposure chambers

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

    SciTech Connect

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

    1993-12-31

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

  2. Exposure chamber

    DOEpatents

    Moss, Owen R.; Briant, James K.

    1983-01-01

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

  3. Exposure chamber

    DOEpatents

    Moss, Owen R.

    1980-01-01

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

  4. [Radon and domestic exposure].

    PubMed

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

    2000-12-01

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

  5. The Japanese Radon and Thoron Reference Chambers

    SciTech Connect

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

    2008-08-07

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

  6. An improved model for the reconstruction of past radon exposure

    SciTech Connect

    Cauwels, P.; Poffijn, A.

    2000-05-01

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

  7. Effects of thoron on a radon detector of pulse-ionization chamber type.

    PubMed

    Ishikawa, T

    2004-01-01

    A radon detector of pulse-ionization chamber (PIC) type could have some sensitivity for thoron. Thus, the presence of thoron could interfere with precise measurement of radon. In the present study, effects of thoron on the most common type of PIC detector (commercial name AlphaGUARD) were investigated using an exposure chamber. The AlphaGUARD was exposed to a mixture of radon and thoron, together with a radon/thoron discriminative monitor that employs a silicon solid-state detector. The thoron sensitivity of the PIC detector was estimated by comparing the two detectors. As a result, the thoron sensitivity was about 10% compared with the radon sensitivity. In other words, the radon concentration (Bq m(-3)) measured with the PIC detector was approximately the sum of the actual radon concentration (Bq m(-3)) and 10% of the thoron concentration (Bq m(-3)). The sensitivity to thoron should be considered in measurements in thoron-enhanced areas. PMID:15103062

  8. Evaluation of the uniformity of concentration of radon in a radon chamber.

    PubMed

    Xiongjie, Zhang; Ye, Zhang; Yang, Liu; Bin, Tang

    2016-04-01

    In order to solve the problem that the evaluation results of the uniformity of concentration of radon in a radon chamber via various methods were difficult to compare, according to its statistical properties, a mathematical model was built to analyze the uniformity of concentration of radon; an evaluation method for the overall uniformity of concentration of radon was proposed on the basis of single-factor multi-group ANOVA, and a detection method for nonuniform points in a radon chamber was proposed on the basis of single-factor two-group t-test; an evaluation process of the uniformity of concentration of radon in a radon chamber was established. The proposed method was applied to evaluate the HD-6 small and medium-sized radon chambers and achieved good results. PMID:26821207

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

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

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

  10. 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.

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

    NASA Astrophysics Data System (ADS)

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

    2014-02-01

    Soil based building materials known to contain various amounts of natural radionuclide mainly 238U and 232Th series and 40K. 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 222Radon and its progenies which arise from the decay of 226Ra. 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-3, 192 Bq m-3, 176 Bq m-3 and 28 Bq m-3, respectively. The result indicates that the radon concentration in the studied building materials have more than 100 Bq m-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-1, 4.85 mSv y-1, 4.44 mSv y-1 and 0.72 mSv y-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-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.

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

    PubMed

    Janik, M; Yonehara, H

    2015-06-01

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

  13. 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}.

  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. 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.

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

    PubMed

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

    2013-11-01

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

  17. Measuring radon concentration in air using a diffusion cloud chamber

    NASA Astrophysics Data System (ADS)

    Cases, R.; Ros, E.; Zúñiga, J.

    2011-09-01

    Radon concentration in air is a major concern in lung cancer studies. A traditional technique used to measure radon abundance is the charcoal canister method. We propose a novel technique using a diffusion cloud chamber. This technique is simpler and can easily be used for physics demonstrations for high school and university students.

  18. Application of an equilibrium-based model for diffusion barrier charcoal canisters in a small volume non-steady state radon chamber.

    PubMed

    Lehnert, A L; Thompson, K H; Kearfott, K J

    2011-02-01

    Radon in indoor air is often measured using activated charcoal in canisters. These are generally calibrated using large, humidity- and temperature-controlled radon chambers capable of maintaining a constant radon concentration over several days. Reliable and reproducible chambers are expensive and may be difficult to create and maintain. This study characterizes a small radon chamber in which Rn gas is allowed to build up over a period of several days for use in charcoal canister calibration and educational demonstrations, as well as various radon experiments using charcoal canisters. Predictive models have been developed that accurately describe radon gas kinetics in the charcoal canisters. Three models are available for kinetics in the small chamber with and without radon-adsorbing charcoal canisters. Presented here are both theoretical and semi-empirical applications of this equilibrium-based model of radon adsorption as applied to canisters in the small chamber. Several charcoal canister experiments in the small chamber with an equilibrium-based model of radon adsorption applied are reported. Results show that it is necessary to include a continuous radon monitor in the chamber during canister exposures, as the radon removal rate is highly variable. Furthermore, the presence of the canisters significantly decreases the amount of radon in the small chamber, especially when several canisters are present. It was found that canister response in the small chamber is largely consistent with the equilibrium-based model for both applications, with average errors of 1% for the theoretical application and -4% for the semi-empirical approach.

  19. Radon exposure and oropharyngeal cancer risk.

    PubMed

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

    2015-12-01

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

  20. Potential health effects of indoor radon exposure.

    PubMed Central

    Radford, E P

    1985-01-01

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

  1. 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.

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

    PubMed

    Kotrappa, Payasada; Stieff, Frederick

    2009-08-01

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

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

    SciTech Connect

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

    2008-08-07

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

  4. Effects of exposure uncertainty on estimation of radon risks

    SciTech Connect

    Chambers, D.B.; Lowe, L.M.; Stager, R.H.; Reilly, P.M.; Duport, P.

    1992-12-31

    Estimates of lung-cancer risk from exposure to radon daughters are largely based on epidemiological studies of underground miners. The reliability of exposure data for these miners is a cause for concern, as actual workplace measurements of radon and/or radon-daughter levels are either sparse or absent for the early years of mining, when much of the exposure occurred.

  5. Avian inhalation exposure chamber

    DOEpatents

    Briant, James K.; Driver, Crystal J.

    1992-01-01

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

  6. Avian inhalation exposure chamber

    DOEpatents

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

    1992-05-05

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

  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. Variation of the unattached fraction of radon progeny and its contribution to radon exposure.

    PubMed

    Guo, Lu; Zhang, Lei; Guo, Qiuju

    2016-06-01

    The unattached fraction of radon progeny is one of the most important factors for radon exposure evaluation through the dosimetric approach. To better understand its level and variation in the real environment, a series of field measurements were carried out indoors and outdoors, and radon equilibrium equivalent concentration was also measured. The dose contribution of unattached radon progeny was evaluated in addition. The results show that no clear variation trend of the unattached fraction of radon progeny is observed in an indoor or outdoor environment. The average unattached fraction of radon progeny for the indoors and outdoors are (8.7  ±  1.6)% and (9.7  ±  2.1)%, respectively. The dose contribution of unattached radon progeny to total radon exposure is some 38.8% in an indoor environment, suggesting the importance of the evaluation on unattached radon progeny. PMID:27171653

  9. 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....

  10. 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....

  11. 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....

  12. 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....

  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....

  14. 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.

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

    EPA Science Inventory

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

  16. 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.

  17. Design and performance of a recirculating radon-progeny aerosol generation and animal inhalation exposure system

    SciTech Connect

    Newton, G.J.; Cuddihy, R.G.; Yeh, H.C.; Boecker, B.B.

    1992-12-31

    At Inhalation Toxicology Research Institute we are conducting inhalation studies that expose laboratory animals to {sup 222}Rn progeny attached to vector aerosols typical of indoor and mine environments. These studies require exposures of up to 1500 working level months within a few hours. Thus, large amounts of {sup 226}Ra are needed to produce the gaseous {sup 222}Rn. A once-through exposure system was considered impractical because of statutory discharge limitations for radon and the large amounts of radium required. We therefore designed and constructed a recirculating exposure system that removes the aerosol after it has passed through the exposure chambers and recirculates the remaining purified radon. The purified radon and air mixture is then passed into a reaction aging chamber, where ingrowth of the progeny and their attachment to vector aerosols occur. The design includes (1) allowance for 45 mg {sup 226}Ra in the radon generator, (2) 40 L min{sup {minus}1} total flow rate, (3) CO{sub 2} removal, (4) reconstitution of oxygen tension and water vapor content to ambient levels, and (5) a trap for radon gas. Radon progeny exposure concentrations in the range of 5,000 to 100,000 working levels have been produced.

  18. Residential radon exposure and lung cancer

    SciTech Connect

    Neuberger, J.S.

    1994-12-31

    Epidemiological studies of underground uranium and hard-rock miners, as well as animal experiments, indicate that the decay products of radon gas are a contributory cause of lung cancer. While one might expect that residential radon (progeny) exposure might be linked to an increase in lung cancer rates, sufficient evidence from residential studies is required to support this assumption. To date this evidence has not been definitive enough. There are differences in age, sex, dust exposure, and smoking between groups exposed in mines and in homes. A number of published studies have addressed this question; a number of studies are under way. The composite results from these studies may be useful in reducing the uncertainty. This paper summarizes and critiques results and discusses several methodological issues related to the studies.

  19. Measurement of 210Po atoms content in glass as an indicator of long-term exposure to radon.

    PubMed

    Jankowski, J; Olszewski, J; Skubalski, J

    1999-01-01

    Measurements of exposure to radon are performed using numerous research methods which register either temporary or periodic radon concentrations. The method presented below allows for the estimation of average radon concentration in the past. This is possible due to indirect measurement of the contents of 210Pb embedded in glass structure. The half-life of 210Pb is about 22 years. A number of exposures of window glass to radon have been carried out in laboratory conditions (radon chamber) and the obtained results were used to calculate the coefficient that renders it possible to define global indoor exposure to radon. The registration was made using a track detector CR-39, which records alpha particles resulting from the disintegration of 210Po, one of 222Rn decay products.

  20. A summary of EPA radon chamber tests and results for rounds 3 and 4 of the National Radon Measurement Proficiency Program

    SciTech Connect

    Smith, J.M.; Sensintaffar, E.L.

    1993-02-01

    The US Environmental Protection Agency`s Office of Radiation and Indoor Air (ORIA) established the National Radon Measurement Proficiency (RMP) Program in 1986. Through this voluntary program, participants can demonstrate their ability to measure radon and/or radon decay products by submitting their detection devices to a blind test in a designated radon chamber. In this report, two EPA radon and radon decay products test chambers (chambers A and C) located at the National Air and Radiation Environmental Laboratory in Montgomery, Alabama are described. These chambers were used to expose detectors submitted for testing in Round 4 of the National Radon Measurement Proficiency Program and are used routinely for calibration purposes. Also described are the measurement and calibration procedures which were used to establish the official target values for radon and radon decay products concentrations during RMP Round 4 testing. The results for RMP Round 3 (conducted at the US DOE Environmental Measurements Laboratory radon chamber in New York) and RMP Round 4 (conducted in the two NAREL chambers) are discussed and compared. Following Round 4, the NAREL staff analyzed the collective performance for each measurement method tested in these rounds and found that all methods agreed with the target values within expected limits except for RPISU`s and charcoal adsorbers. After analyzing the RMP4 results, NAREL staff spent several months evaluating the difference in charcoal adsorber response between Round 3 and 4 by performing radon chamber tests using EPA 4-inch, open-faced charcoal adsorbers.

  1. [The methods of assessment of health risk from exposure to radon and radon daughters].

    PubMed

    Demin, V F; Zhukovskiy, M V; Kiselev, S M

    2014-01-01

    The critical analysis of existing models of the relationship dose-effect (RDE) for radon exposure on human health has been performed. Conclusion about the necessity and possibility of improving these models has been made. A new improved version ofthe RDE has been developed. A technique for assessing the human health risk of exposure to radon, including the method for estimating of exposure doses of radon, an improved model of RDE, proper methodology risk assessment has been described. Methodology is proposed for the use in the territory of Russia.

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

    PubMed

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

    2010-05-01

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

  3. 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)

  4. Residential radon exposure and risk of lung cancer in Missouri.

    PubMed Central

    Alavanja, M C; Lubin, J H; Mahaffey, J A; Brownson, R C

    1999-01-01

    OBJECTIVES: This study investigated residential radon exposure and lung cancer risk, using both standard radon dosimetry and a new radon monitoring technology that, evidence suggests, is a better measure of cumulative radon exposure. METHODS: Missouri women (aged 30 to 84 years) newly diagnosed with primary lung cancer during the period January 1, 1993, to January 31, 1994, were invited to participate in this population-based case-control study. Both indoor air radon detectors and CR-39 alpha-particle detectors (surface monitors) were used. RESULTS: When surface monitors were used, a significant trend in lung cancer odds ratios was observed for 20-year time-weighted-average radon concentrations. CONCLUSIONS: When surface monitors were used, but not when standard radon dosimetry was used, a significant lung cancer risk was found for radon concentrations at and above the action level for mitigation of houses currently used in the United States (148 Bqm-3). The risk was below the action level used in Canada (750 Bqm-3) and many European countries (200-400 Bqm-3). PMID:10394313

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

    PubMed

    Tan, Yanliang; Xiao, Detao

    2013-10-01

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

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

    PubMed

    Tsapalov, Andrey; Kovler, Konstantin; Miklyaev, Peter

    2016-08-01

    Radon exhalation rate from the soil surface can serve as an important criterion in the evaluation of radon hazard of the land. Recently published international standard ISO 11665-7 (2012) is based on the accumulation of radon gas in a closed container. At the same time since 1998 in Russia, as a part of engineering and environmental studies for the construction, radon flux measurements are made using an open charcoal chamber for a sampling duration of 3-5 h. This method has a well-defined metrological justification and was tested in both favorable and unfavorable conditions. The article describes the characteristics of the method, as well as the means of sampling and measurement of the activity of radon absorbed. The results of the metrological study suggest that regardless of the sampling conditions (weather, the mechanism and rate of radon transport in the soil, soil properties and conditions), uncertainty of method does not exceed 20%, while the combined standard uncertainty of radon exhalation rate measured from the soil surface does not exceed 30%. The results of the daily measurements of radon exhalation rate from the soil surface at the experimental site during one year are reported. PMID:27132250

  7. Theoretical calculation on CR-39 response for radon measurements and optimum diffusion chambers dimensions

    NASA Astrophysics Data System (ADS)

    Askari, H. R.; Ghandi, Kh.; Rahimi, M.; Negarestani, A.

    2008-11-01

    One method to measure radon gas concentration in the air with a long time of radiation is trace chemical etching technique. There is a direct proportion between the number of traces on solid-state nuclear track detectors (SSNTDs) and activity concentration of radon. In this paper, calibration constant for a cylindrical chamber with CR-39 detector has been measured analytically. Using this measurement, trace curves on the base of concentration for chambers with different heights and radii have been drawn. The results show that to measure radon gas concentration, the optimum chamber should have a height between 3.5 and 4 cm and a radius between 2.5 and 3.2 cm.

  8. 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

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

    SciTech Connect

    Not Available

    1988-03-01

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

  10. Cancer risks from exposure to radon in homes

    SciTech Connect

    Axelson, O.

    1995-03-01

    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. 97 refs., 3 tabs.

  11. Radon-daughter exposures in energy-efficient buildings

    SciTech Connect

    Nero, A.V.; Berk, J.V.; Boegel, M.L.; Hollowell, C.D.; Ingersoll, J.G.; Nazaroff, W.W.

    1981-10-01

    A radon concentration of 1 pCi/1 (37 Bq/m/sup 3/) appears to lie in the range that is typical for air inside US residential buildings. Moreover, some US residences have concentrations higher than 1 pCi/1, sometimes by an order of magnitude, implying significant individual risk to occupants. For typical radon daughter equilibrium ratios, this concentration corresponds to a radon daughter exposure rate of 0.2 working level months (WLM) per year. This exposure rate may account for a significant lung cancer incidence if data on lung cancers per unit exposure in miners are applicable to such low exposures. Reductions in air exchange rates may rise the typical exposure rate and even increase it to unacceptable levels in some cases. Measures that reduce energy use by reducing natural infiltration or mechanical ventilation in new or retrofit buildings are therefore undergoing severe scrutiny. Lawrence Berkeley Laboratory has performed measurements in buildings specifically designed to use energy efficiently or utilize solar heating. In many of these buildings radon concentrations appear to arise primarily from soil underlying the buildings. Measures to control higher levels, e.g., by mechanical ventilation with heat recuperation, appear to be economical. However, to evaluate energy-saving programs adequately requires a much more comprehensive characterization of radon sources (for example, by geographical area) and a much fuller understanding of the dynamics of radon and its daughters indoors than now exist.

  12. Relative biological effectiveness of alpha particles at radon exposure.

    PubMed

    Zhukovsky, M; Bastrikova, N; Vasilyev, A

    2015-06-01

    The relative biological effectiveness (RBE) of alpha particles at radon exposure is estimated by comparison of radiation risks at external gamma exposure and radon exposure in different situations. For external gamma exposure, the BEIR VII model of radiation risk assessment was used. For occupational and indoor radon exposure, models such as BEIR VI, WISMUT, Tomasek's and combined miners population were considered. It was demonstrated that RBE values are strongly dependent on models of radiation risk assessment used for RBE calculation, sex of exposed peoples and age at the exposure. The average values of RBE in dependence on model of risk assessment choice are in the range from 1.5 to 12.0 for males and in the range from 0.34 to 2.7 for females.

  13. Relative biological effectiveness of alpha particles at radon exposure.

    PubMed

    Zhukovsky, M; Bastrikova, N; Vasilyev, A

    2015-06-01

    The relative biological effectiveness (RBE) of alpha particles at radon exposure is estimated by comparison of radiation risks at external gamma exposure and radon exposure in different situations. For external gamma exposure, the BEIR VII model of radiation risk assessment was used. For occupational and indoor radon exposure, models such as BEIR VI, WISMUT, Tomasek's and combined miners population were considered. It was demonstrated that RBE values are strongly dependent on models of radiation risk assessment used for RBE calculation, sex of exposed peoples and age at the exposure. The average values of RBE in dependence on model of risk assessment choice are in the range from 1.5 to 12.0 for males and in the range from 0.34 to 2.7 for females. PMID:25979745

  14. Radon progeny size distributions and enhanced deposition effects from high radon concentrations in an enclosed chamber.

    PubMed

    Leonard, Bobby E

    2004-01-01

    Prior work studying radon progeny in a small enclosed chamber found that at high (222)Rn concentrations an enhanced surface deposition was observed. Subsequent measurements for unfiltered air showed minimal charged particle mobility influence. Progeny particle size measurements reported here, performed at the US Department of Energy Environmental Measurement Laboratory (now with Home Security Department), using the EML graded screen array (GSA) system show in unfiltered air that the high (222)Rn levels causes a reduction in the attached (218)Po progeny airborne particulates and formation of additional normal sized unattached ( approximately 0.80 nm) and also even smaller (218)Po below 0.50 nm. At a (222)Rn level of 51 kBq m(-3), 73% of all (218)Po are of a mean particle diameter of about 0.40 +/- 0.02 nm. At this (222)Rn level, the ratio of (218)Po to (222)Rn airborne concentrations is reduced significantly from the concentration ratio at low (222)Rn levels. Similar reductions and size reformations were observed for the (214)Pb and (214)Bi/Po progeny. The particle size changes are further confirmed using the plateout rates and corresponding deposition velocities. The Crump and Seinfeld deposition theory provides the corresponding particle diffusion coefficients. With the diffusion coefficient to ultrafine clustered particle diameter correlation of Ramamurthi and Hopke, good agreement is obtained between EML GSA and deposition velocity data down to 0.40 nm. Strong evidence is presented that the progeny size reduction is due to, as a result of air ionization, the increased neutralization rate (primarily from electron scavenging of OH molecules) of the initially charged progeny. This is shown to increase with the (1/2) power of (222)Rn concentration and relative humidity as well as increased air change rate in the chamber. These results imply that at (222)Rn levels above 50 kBq m(-3), at relative humidity of 52%, a considerable reduction in lung dose could occur from

  15. Radon exposure assessment in a former uranium production facility

    SciTech Connect

    Akbar-Khanzadch, F.; Merrill, E.A.

    1996-06-01

    Storage of radon-producing materials in three silos and six waste pits is one of the major environmental and occupational issues at a former uranium production facility, now a Superfund Site. The concentrations of radium up to 190,000 pCi g{sup -1} for silos and up to 1,200 pCi g{sup -1} for waste pits have been reported. This study was conducted to identify conditions and climatic factors that contribute to higher radon levels and to assess workers` exposure at the site. Data covering a 12-mo period were compiled from monitoring radon levels by hourly real-time indoor (within 3 buildings) and outdoor (at 14 on-site and 2 off-site stations) and from hourly site specific meteorological information. The ranges of radon levels were 0.05-98.8 pCi L{sup -1} outdoor on-site, 0.1-8.9 pCi L{sup -1} outdoor off-side, and 0.05-3.0 pCi L{sup -1} indoor on-site. Only radon levels in the vicinity of the storage silos, which is an exclusion zone, were significantly higher than levels off-site. Significantly higher levels of radon were detected in the production areas vs. those at the perimeter areas, suggesting that there were significant sources of on-site radon contamination other than the silos. Radon concentrations showed diurnal variations, maximum levels occurring at early morning and minimum levels in the afternoon. A seasonal variation was also observed, with radon levels highest during mid summer while lowest during winter. Wind direction, wind speed, relative humidity, and ambient temperature appeared to be the most significant predictors of radon concentration. The dose, calculated by using exposure models and annual average levels of radon in the work area, was below recommended exposure limits. These results suggest that the emission control methods at this site have been effective in maintaining environmental radon contamination and workers` exposure at acceptable levels.

  16. 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.

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

    SciTech Connect

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

    2015-07-23

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

  18. An atmospheric exposure chamber for small animals

    NASA Technical Reports Server (NTRS)

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

    1982-01-01

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

  19. Lung cancer and exposure to radon in women - New Jersey

    SciTech Connect

    Schoenberg, J.B.; Klotz, J.B.; Wilcox, H.B.; Gel-del-Real, M.; Stemhagen, A. ); Nicholls, G.P. )

    1989-11-17

    In 1985, the New Jersey State Department of Health (NJDOH) initiated an epidemiologic study of lung cancer and exposure to radon in New Jersey women. In collaboration with the New Jersey State Department of Environmental Protection and the National Cancer Institute, NJDOH examined whether exposure to radon in homes is associated with increased lung cancer risk. This study was based on a previous statewide case-control study of risk for lung cancer. The data indicated that year-round exposures in living areas were two to five times lower than basement measurements taken during heating season. The difference increased with higher concentrations.

  20. Acute Exposure from RADON-222 and Aerosols in Drinking Water

    NASA Astrophysics Data System (ADS)

    Bernhardt, George Paul, IV

    Radon-222 in water is released when the water is aerated, such as during showering. As a result, a temporary burst of radon-222 can appear as a short term, or acute, exposure. This study looked at homes with radon-222 concentrations in water from 800 picocuries per liter (pCi/l) to 53,000 pCi/l to determine the buildup of radon gas in a bathroom during showering. Samples from the tap and drain, compared to determine the percentage of radon-222 released, showed that between 58% and 88% of radon-222 in the water was released. The resultant radon-222 increase in air, measured with a flow-through detector, ranged from 2 pCi/l to 114 pCi/l in bathrooms due to a 10 to 15 minute shower with water flow rates ranging from 3 l/min to 6 l/min. Significantly, these rates did not fall rapidly but stayed approximately the same for up to 15 minutes after the water flow ceased. In examining exposures, the true danger is in the radon-222 progeny rather than the radon itself. The progeny can be inhaled and deposited in the tracheobronchial passages in the lung. Filter samples of bathroom air measured in a portable alpha spectrometer showed an increase in radon-222 progeny, notably polonium-218 and -214, in the air after showering. These increases were gradual and were on the order of 0.5 pCi/l at the highest level. Tap samples measured in a portable liquid scintillator showed that the progeny are present in the water but are not in true secular equilibrium with the radon-222 in the water. Therefore, the radon-222 does not have to decay to produce progeny since the progeny are already present in the water. A two stage sampler was used to examine the percentage of radiation available in aerosols smaller than 7 microns. Repeated trials showed that up to 85% of the radiation available in the aerosols is contained in the smaller, more respirable particles.

  1. Potential lung cancer risk from indoor radon exposure

    SciTech Connect

    Harley, N.H.; Harley, J.H. )

    1990-09-01

    The contribution of radon daughter exposure to excess lung cancer in underground miners is universally accepted. These miners received exposures from tens to thousands of WLM in a relatively few years. Although the miners were also exposed to other noxious agents in mines, the appearance of the excess lung cancer mortality in several types of mines and the increase with increasing exposure provide convincing evidence of the role of radon as the carcinogen. It is conceivable that exposures to radon at an average concentration of one to two pCi/liter, the levels for a majority of homes, might not produce excess lung cancers. This would require that a lifetime exposure at low concentrations produce a different response from that of a few years at higher levels for the miners. This is unlikely but not impossible. The current environmental epidemiology is of varying quality. The better studies may give some answers in a few years. These studies are more likely to establish an upper limit of risk than to provide an exposure-response model. Present risk estimates cannot be used accurately in estimating the overall lung cancer risk to the US population, since there are no good data on average exposure and exposure distribution. For example, the number of homes above the EPA guideline of four pCi/liter may range from two million to 10 million. An estimate of the actual radon exposure in the US may be forthcoming from a planned EPA survey, but these data will not be available for a few years. In the conservative tradition of radiation protection, indoor radon exposures in homes are estimated to produce a number of excess lung cancers in the population.22 references.

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

    SciTech Connect

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

    2008-08-07

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

  3. 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

    2016-04-01

    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

  4. 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.

  5. Measurement of short-lived radon progenies by simultaneous αγ-spectrometry at the German radon reference chamber

    NASA Astrophysics Data System (ADS)

    Paul, A.; Röttger, S.; Honig, A.; Sulima, T.; Buchholz, A.; Keyser, Uwe

    1999-02-01

    In the German radon reference chamber, the short-lived radon progenies are separated by a sample tube according to the attached or unattached fraction, while their activity concentration is afterwards measured by simultaneous α- and γ-spectrometry. The results are expressed by the equilibrium factor F and the unattached fraction fp (International Commission on Radiological Protection, ICRP Publication 50, Ann. ICRP 17 (1987) 1). Both F and fp, can be therefore studied with respect to the full set of environmental parameters, e.g. temperature, humidity, air pressure and aerosol concentration (Honig et al., Nucl. Instr. and Meth. A 416 (1998) 525). Up to now, well-defined and stable equilibrium factors in the interval from 0.1 to 1.0 have been established. In correlation with this, the unattached fraction can be varied from 0.01 to 0.9. The sample and measuring technique for the short-lived radon progenies described in this work is the basis for fundamental studies with regard to the equilibrium factor and the unattached fraction as well as for application as a calibration facility.

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

    PubMed

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

    2013-10-01

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

  7. Radon

    MedlinePlus

    ... with elevated radon underwent changes to reduce radon pollution. 1 How Can Radon Be Detected? The only ... Association Applauds EPA’s Update to Cross-State Air Pollution Rule News: New Truck Efficiency Standards Expected to ...

  8. The modified model of radiation risk at radon exposure.

    PubMed

    Zhukovsky, Michael; Demin, Vladimir; Yarmoshenko, Ilia

    2014-07-01

    The combined modified model of risk assessment from an indoor radon exposure is proposed. Multiplicative dependence on fatal lung cancer is used. The model has been developed on the basis of the modern health risk theory and the results of epidemiological studies with the special attention to the results of the European combined study and the WISMUT miners cohort study. The model is presented as an age-specific relative risk coefficient for a single (short-term) exposure. The risk coefficient for an extended exposure can be obtained from this risk coefficient in the accordance with the risk theory. The smoothed dependences of the risk coefficients on time since exposure and attained age and radon progeny concentration are suggested.

  9. 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.

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

    PubMed

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

    2013-07-01

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

  11. 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.

  12. Predicted reduction in lung cancer risk following cessation of smoking and radon exposure

    SciTech Connect

    Ennever, F.K. )

    1990-03-01

    Recently there has been considerable public and regulatory concern that radon, produced by the decay of naturally occurring uranium, can accumulate in homes, offices, and schools at levels that may substantially increase the risk of lung cancer. The major cause of lung cancer is smoking, and radon appears to interact multiplicatively with smoking in causing lung cancer. Thus, the most effective way to reduce the increased risk of lung cancer resulting from radon exposure is to cease smoking. In this paper, a model for the risks associated with radon exposure that was developed by a committee of the National Academy of Sciences is used to calculate the benefits, in terms of reduction in lifetime risk of lung cancer, of ceasing to smoke, ceasing radon exposure, or ceasing both. Ceasing to smoke is considerably more beneficial than ceasing radon exposure, and thus policymakers addressing the health effects of radon should place priority on encouraging individuals to stop smoking.

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

    ERIC Educational Resources Information Center

    Neuberger, John S.; And Others

    1992-01-01

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

  14. Residential radon exposure and lung cancer: 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

  15. Comparative risk assessment of residential radon exposures in two radon-prone areas, Stei (Romania) and Torrelodones (Spain).

    PubMed

    Sainz, Carlos; Dinu, Alexandra; Dicu, Tiberius; Szacsvai, Kinga; Cosma, Constantin; Quindós, Luis Santiago

    2009-07-15

    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. 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). 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 m(-3) and 366 Bq m(-3) in the Spanish region. The results are computed with the BEIR VI report estimates using the age-duration model at an exposure rate below 2650 Bq m(-3). We used the EC Radon Software to calculate the lifetime lung cancer death risks for individuals groups in function of attained age, radon exposures and tobacco consumption. A total of 233 lung cancer deaths were observed in the Stei area for a period of 13 years (1994-2006), which is 116.82% higher than expected from the national statistics. In addition, the number of deaths estimated for the year 2005 is 28, which is worth more than 2.21 times the amount expected by authorities. In comparison, for Torrelodones was rated a number of 276 deaths caused by lung cancer for a period of 13 years, which is 2.09 times higher than the number expected by authorities. For the year 2005 in the Spanish region were reported 32 deaths caused by pulmonary cancer, the number of deaths exceeding seen again with a factor of 2.10 statistical expectations. This represents a significantly evidence that elevated risk can strongly be associated with cumulated radon exposure.

  16. Comparative risk assessment of residential radon exposures in two radon-prone areas, Stei (Romania) and Torrelodones (Spain).

    PubMed

    Sainz, Carlos; Dinu, Alexandra; Dicu, Tiberius; Szacsvai, Kinga; Cosma, Constantin; Quindós, Luis Santiago

    2009-07-15

    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. 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). 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 m(-3) and 366 Bq m(-3) in the Spanish region. The results are computed with the BEIR VI report estimates using the age-duration model at an exposure rate below 2650 Bq m(-3). We used the EC Radon Software to calculate the lifetime lung cancer death risks for individuals groups in function of attained age, radon exposures and tobacco consumption. A total of 233 lung cancer deaths were observed in the Stei area for a period of 13 years (1994-2006), which is 116.82% higher than expected from the national statistics. In addition, the number of deaths estimated for the year 2005 is 28, which is worth more than 2.21 times the amount expected by authorities. In comparison, for Torrelodones was rated a number of 276 deaths caused by lung cancer for a period of 13 years, which is 2.09 times higher than the number expected by authorities. For the year 2005 in the Spanish region were reported 32 deaths caused by pulmonary cancer, the number of deaths exceeding seen again with a factor of 2.10 statistical expectations. This represents a significantly evidence that elevated risk can strongly be associated with cumulated radon exposure. PMID:19428051

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

    PubMed

    Tan, Yanliang; Tokonami, Shinji; Hosoda, Masahiro

    2015-06-01

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

  18. Radon

    MedlinePlus

    You can't see radon. And you can't smell it or taste it. But it may be a problem in your home. Radon comes from the natural breakdown of uranium in soil, rock, and water. Radon is the second leading cause of lung cancer ...

  19. 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...

  20. 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).

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

    SciTech Connect

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

    2013-08-08

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

  2. 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.

  3. Residential radon exposure and lung cancer: an overview of ongoing studies

    SciTech Connect

    Neuberger, J.S. )

    1992-11-01

    This review paper summarizes the ongoing case/control studies of residential radon exposure and lung cancer. Discussion is offered in the areas of lung cancer risk factors, sample size requirements, radon exposure assessment, and meta-analysis. This is an important topic that deserves a best effort' study design. 22 references.

  4. Plant exposure laboratory and chambers. Volume 1

    SciTech Connect

    McFarlane, C.; Pfleeger, T.

    1986-01-01

    The research is to learn the factors that control plant uptake, translocation, and metabolism of anthropogenic organic chemicals. Understanding these processes is essential to predict food contamination and environmental damage from various agricultural and industrial pollutants. Contamination of plants is only one component, but since plants are the fulcrum upon which all nourishment systems depend, understanding the ways they become contaminated is critical to prudent production, transportation, and use of organic chemicals. These efforts to identify the controlling mechanisms of these phenomena require an understanding of the physiological parameters of the plants during uptake and translocation of the extraneous chemicals. Since the chemicals of interest are toxic and studies generally include /sup 14/C as a label for monitoring chemical kinetics, containment is an important criterion. The paper describes the laboratory and support system, the exposure chambers, the computer system, and the plant hydroponic nursery built to accomplish this research.

  5. 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

  6. 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.

  7. Retrospective assessment of indoor radon exposure by measurements of embedded 210Po activity in glass objects

    NASA Astrophysics Data System (ADS)

    Ramola, R. C.; Gusain, G. S.; Prasad, Ganesh

    In most of the epidemiological studies contemporary radon measurements have been used as surrogates for radon concentrations in past decades even though changes in radon levels and residence may have occurred. Short-lived radon progeny may deposit on available surfaces in dwellings thus giving rise over time to a build up of long-lived progeny. Airborne radon decay products can be deposited and implanted through alpha recoil into the glass surfaces. On glass surface, activities of 210Po may arise as a result of the decay of recoil implanted activity following the alpha decay of surface deposited 218Po or 214Po. Measurement of 210Po implanted on a household glass is a method that can be employed to retrospectively determine the historic level of radon in dwellings. This method is based on the assumption that levels of recoil implanted 210Po in the glass provide a measure of time integrated radon concentration in the environment in which the glass has been located. The surface deposited activity of the radon progenies, which then become implanted in the glass by alpha recoil, is believed to reflect past exposure to airborne activity. Such retrospective measurements on glass are valuable in estimating the human dose derived from radon during the time of exposure. In this paper an account is given of the principles and some field applications of a retrospective technique, using the alpha track detectors, CR-39 and LR-115, to measure 210Po implanted in glass surfaces (surface traps). By using this CR-LR difference technique, the cumulative radon exposure in a dwelling in past decades may be estimated. This method provides reliable radon exposure data as a support to epidemiological studies concerning the health effects of radon exposure in the living environment.

  8. Variation of radon-222 concentration in exposure systems air under different conditions of exposure

    NASA Astrophysics Data System (ADS)

    Mamoon, A.; Abdul-Fattah, A. A.; Qari, T. M.

    1994-07-01

    Simplified, laboratory scale systems, namely ordinary laboratory desiccators and cylindrical containers were tested with regard to their reliability as exposure systems for determining certain parameters of radon emanation from locally obtained crushed granite rock samples. The samples were placed inside the exposure systems. Activity concentration of emanated radon in the exposure systems air increased with increase of mass of granite sample in the desiccator and with length of the exposure period. Activity concentration of radon was high near the granitic source but decreased with vertical distance from it when the exposure system was semiclosed but activity was homogeneous when the system was completely closed. The cylindrical exposure system was used in assessing Ra-226 content in some crushed granitic samples identified as altered alkali granite and found to be: 0.024 Bq g-1 (0.65 pCig-1). Rn-222 emanation rate from the same samples was: 0.013 Bq m-2 s-1 (0.34 pCi m-2 s-1). Saturation density thickness for a mixed sample of pure and alkali granites was found to be 116 g cm-2. The results agree in general with reported observations and support the reliability of the exposure systems used.

  9. 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.

  10. 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.

  11. Experiences and concerns on lung cancer and radon daughter exposure in mines and dwellings in Sweden.

    PubMed

    Axelson, O

    1983-01-01

    A high mortality from lung cancer among miners was reported from Central Europe already in the 19th century. In the 60s and 70s several reports have indicated an increased lung cancer mortality among uranium miners and other metal-miners, e.g. in the US, UK, France and Sweden, but also among fluorspar miners in Canada. The cause is supposed to be the decay products of radon as emanating from the rocks, i.e. the alpha-radiation from short-lived radon daughters. Radon and radon daughter exposure in dwellings have more recently attracted interest as a potential hazard to the general population, especially since radon daughter concentrations seem to have increased due to more effective insulation for energy saving. In many Swedish houses the radon daughter exposures amount to levels similar to that of mines. Some epidemiological evaluations of the relationship between lung cancer and exposure to radon daughters, i.e. residency in stone houses versus wooden houses (with and without consideration of the contribution of radon from the ground underneath the houses), seem to indicate a risk also to the general population and, moreover, the risk of smoking seems to be several times greater in stone houses than in wooden houses, the latter usually having less radon daughters on the average.

  12. 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

  13. 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

  14. Attributable risk of lung cancer deaths due to indoor radon exposure.

    PubMed

    Kim, Si-Heon; Hwang, Won Ju; Cho, Jeong-Sook; Kang, Dae Ryong

    2016-01-01

    Exposure to radon gas is the second most common cause of lung cancer after smoking. A large number of studies have reported that exposure to indoor radon, even at low concentrations, is associated with lung cancer in the general population. This paper reviewed studies from several countries to assess the attributable risk (AR) of lung cancer death due to indoor radon exposure and the effect of radon mitigation thereon. Worldwide, 3-20 % of all lung cancer deaths are likely caused by indoor radon exposure. These values tend to be higher in countries reporting high radon concentrations, which can depend on the estimation method. The estimated number of lung cancer deaths due to radon exposure in several countries varied from 150 to 40,477 annually. In general, the percent ARs were higher among never-smokers than among ever-smokers, whereas much more lung cancer deaths attributable to radon occurred among ever-smokers because of the higher rate of lung cancers among smokers. Regardless of smoking status, the proportion of lung cancer deaths induced by radon was slightly higher among females than males. However, after stratifying populations according to smoking status, the percent ARs were similar between genders. If all homes with radon above 100 Bq/m(3) were effectively remediated, studies in Germany and Canada found that 302 and 1704 lung cancer deaths could be prevented each year, respectively. These estimates, however, are subject to varying degrees of uncertainty related to the weakness of the models used and a number of factors influencing indoor radon concentrations.

  15. Attributable risk of lung cancer deaths due to indoor radon exposure.

    PubMed

    Kim, Si-Heon; Hwang, Won Ju; Cho, Jeong-Sook; Kang, Dae Ryong

    2016-01-01

    Exposure to radon gas is the second most common cause of lung cancer after smoking. A large number of studies have reported that exposure to indoor radon, even at low concentrations, is associated with lung cancer in the general population. This paper reviewed studies from several countries to assess the attributable risk (AR) of lung cancer death due to indoor radon exposure and the effect of radon mitigation thereon. Worldwide, 3-20 % of all lung cancer deaths are likely caused by indoor radon exposure. These values tend to be higher in countries reporting high radon concentrations, which can depend on the estimation method. The estimated number of lung cancer deaths due to radon exposure in several countries varied from 150 to 40,477 annually. In general, the percent ARs were higher among never-smokers than among ever-smokers, whereas much more lung cancer deaths attributable to radon occurred among ever-smokers because of the higher rate of lung cancers among smokers. Regardless of smoking status, the proportion of lung cancer deaths induced by radon was slightly higher among females than males. However, after stratifying populations according to smoking status, the percent ARs were similar between genders. If all homes with radon above 100 Bq/m(3) were effectively remediated, studies in Germany and Canada found that 302 and 1704 lung cancer deaths could be prevented each year, respectively. These estimates, however, are subject to varying degrees of uncertainty related to the weakness of the models used and a number of factors influencing indoor radon concentrations. PMID:26925236

  16. "Radon Concentration Survey in Inner Rooms from Deputy Chamber and National Congress—Brasília/DF"

    NASA Astrophysics Data System (ADS)

    Nícoli, Ieda Gomes; Cardozo, Kátia Maria; de Azevedo Gouvea, Vandir

    2008-08-01

    Radon gas has been monitored in many environments such as rural and urban houses, high natural radioactivity areas and underground mining regions. Nevertheless few data are reported in literature about studies in state buildings. So we get in touch with these buildings managers, where work the Deputy Chamber and the National Congress in Brasília—DF, in order to obtain radon data in these state buildings, so representative for brazilian people. In order to make a preliminary scanning of radon concentration in these buildings, it was put in selected points, radon nuclear track passive detectors type SSNTD, specifically polycarbonate Lexan, which were exposed for periods from two to five months. Afterwards they were sent to Nuclear Engineering Institute in Rio de Janeiro for analysis of 222Rn contents. Derived values, whose average value was about 73 Bq/m3, were all under maximum permissible limits for radon 200 Bq/m3, established by International Comission on Radiological Protection—ICRP 65, for inner environments of houses and state buildings. This work has been coordinated by CNEN Office in Brasélia with effective participation of Nuclear Engineering Institute from CNEN—RJ, that has worked since beginning of april 2004, supplying and analysing radon detectors.

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

    PubMed

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

    2014-07-01

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

  18. Iowa radon leukaemia study: a hierarchical population risk model for spatially correlated exposure measured with error.

    PubMed

    Smith, Brian J; Zhang, Lixun; Field, R William

    2007-11-10

    This paper presents a Bayesian model that allows for the joint prediction of county-average radon levels and estimation of the associated leukaemia risk. The methods are motivated by radon data from an epidemiologic study of residential radon in Iowa that include 2726 outdoor and indoor measurements. Prediction of county-average radon is based on a geostatistical model for the radon data which assumes an underlying continuous spatial process. In the radon model, we account for uncertainties due to incomplete spatial coverage, spatial variability, characteristic differences between homes, and detector measurement error. The predicted radon averages are, in turn, included as a covariate in Poisson models for incident cases of acute lymphocytic (ALL), acute myelogenous (AML), chronic lymphocytic (CLL), and chronic myelogenous (CML) leukaemias reported to the Iowa cancer registry from 1973 to 2002. Since radon and leukaemia risk are modelled simultaneously in our approach, the resulting risk estimates accurately reflect uncertainties in the predicted radon exposure covariate. Posterior mean (95 per cent Bayesian credible interval) estimates of the relative risk associated with a 1 pCi/L increase in radon for ALL, AML, CLL, and CML are 0.91 (0.78-1.03), 1.01 (0.92-1.12), 1.06 (0.96-1.16), and 1.12 (0.98-1.27), respectively. PMID:17373673

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

    PubMed

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

    2014-11-01

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

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

    PubMed

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

    2015-09-01

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

  1. 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

  2. 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

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

    PubMed

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

    2015-10-01

    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

  4. 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

  5. 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.

  6. Models for retrospective quantification of indoor radon exposure in case-control studies

    SciTech Connect

    Gerken, M.; Kreienbrock, L.; Wellmann, J.; Kreuzer, M.; Wichmann, H.E.

    2000-03-01

    In epidemiologic studies on lung cancer risk due to indoor radon the quantification of individual radon exposure over a long time period is one of the main issues. Therefore, radon measurements in one or more dwellings, which in total have been inhabited by the participants for a sufficient time-period, are necessary as well as consideration of changes of building characteristics and ventilation habits, which influence radon concentration. Given data on 1-y alpha-track measurements and personal information from 6,000 participants of case-control studies in West and East Germany, and improved method is developed to assess individual radon exposure histories. Times spent in different rooms of the dwelling, which are known from a personal questionnaire, are taken into account. The time spent outside the house varies substantially among the participants. Therefore, assuming a substantially lower radon exposure outside the dwelling, the residence time constitutes an important aspect of total radon exposure. By means of an analysis of variance, important determinants of indoor radon are identified, namely constant conditions such as type of house, type of construction, year of construction, floor and type of basement, and changeable conditions such as heating system, window insulation, and airing habits. A correction of measurements in former dwellings by factors derived from the analysis is applied if current living conditions differ from those of the participants at the time when they were living in the particular dwellings. In rare cases the adjustment for changes leads to a correction of the measurements with a factor of about 1.4, but a reduction of 5% on average only. Exposure assessment can be improved by considering time at home and changes of building and ventilation conditions that affect radon concentration. The major concern that changes in ventilation habits and building conditions lead to substantial errors in exposure assessment cannot be confirmed in the

  7. Residental radon exposure and lung cancer: Evidence of an urban factor in Iowa

    SciTech Connect

    Neuberger, J.S.; Lynch, C.F.; Kross, B.C.

    1994-03-01

    An ecological study of lung cancer, cigarette smoking, and radon exposure was conducted in 20 Iowa counties. County-based lung cancer incidence data for white female residents of Iowa were stratified according to radon level and smoking status. Cancer incidence data for the period 1973-1990 were obtained from the State Health Registry of Iowa. Smoking level was determined from a randomly mailed survey. Radon level was determined according to an EPA supported charcoal canister survey. Within low smoking counties, rates for all lung cancer and small cell carcinoma were significantly lower (p < 0.05) in the high radon counties relative to the medium and low radon counties. However, within high smoking counties, rates for all lung cancer, adenocarcinoma, and small cell carcinoma were significantly higher (p < 0.05) in the high radon counties relative to the low radon counties. Variations in socioeconomic data for these counties, available through the 1980 and 1990 census, did not explain these results. Lung cancer rates also were significantly increased in urban counties even after holding smoking status constant. Multivariate analyses revealed significant interactions between smoking, urbanization, radon levels, and lung cancer. The results of this hypothesis generating study will be tested in a case/control study now ongoing in Iowa. Analysis will need to include separate evaluations by smoking status, radon level, and residence in urban or rural areas for the major morphologic types of lung cancer. 24 refs., 3 figs., 5 tabs.

  8. 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...

  9. 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.

  10. Dosimetry of radon and thoron exposures: Implications for risks from indoor exposure

    SciTech Connect

    James, A.C.

    1992-12-31

    Current estimates of lung-cancer risks due to the inhalation of radon and its progeny in homes are based on extrapolations of excess mortality observed in populations of underground miners. To project lung-cancer risk to the general public it is necessary to account for any effects that different exposure conditions may have on doses received by critical target cells in the respiratory tract. This paper summarizes the results of a review of aerosol parameters, physiological and biological factors, and cells at risk that are involved in comparing doses between mine and indoor environments. The dose received by sensitive cells in the bronchi from exposure to a given amount of potential alpha-energy (commonly given the unit Working Level Month, WLM) is found to be approximately 20% lower indoors that for healthy underground miners. However, this estimate of the ratio of dose per unit exposure in homes compared to that in mines (termed the {open_quotes}K-factor{close_quotes}) is sensitive to the assumed hygroscopic properties of radon-progeny aerosols. The estimate of K varies from about 0.9, if radon-progeny aerosol particles are assumed not to grow hygroscopically in the respiratory tract, to about 0.6 if the ambient particles are assumed to double in size by hygroscopic growth.

  11. 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.

  12. 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

  13. 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.

  14. 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

  15. Radon exposure and lung cancer: risk in nonsmokers among cohort studies.

    PubMed

    Oh, Sung-Soo; Koh, Sangbaek; Kang, Heetae; Lee, Jonggu

    2016-01-01

    Eleven cohorts of miners occupationally exposed to relatively high concentrations of radon showed a statistically significantly high risk of lung cancer, while three cohorts from the general population showed a relatively low concentration, but the results were not statistically significant. However, the risk of lung cancer tended to increase with increased radon exposure. The risk is likely to have been underestimated due to low statistical power. Therefore, additional well-designed studies on the risk of lung cancer in nonsmokers in the general population with relatively low concentrations of radon exposure are needed in the future. In addition, country-specific preventive policies are needed in order to actively reduce radon exposure and lung cancer incidence in nonsmokers.

  16. Relationship between exposure to radon and various types of cancer

    SciTech Connect

    Cohen, B.L. )

    1993-11-01

    Correlations are studied between average radon levels in 1600 U.S. counties and mortality rates in them from various types of cancer. By far the strongest correlation is with lung cancer, but the sign of the correlation is negative. When smoking prevalence is included in a multiple regression, the large negative correlation between radon and lung cancer is essentially unaffected.

  17. Indoor exposure of population to radon in the FYR of Macedonia.

    PubMed

    Stojanovska, Zdenka; Januseski, Jovan; Boev, Blazo; Ristova, Mimoza

    2012-01-01

    The authors present the results of a year-long survey of the indoor radon concentration levels in the FYR of Macedonia. A total number of 437 dwellings in eight statistical regions were subject to radon concentration measurements by using CR-39 track detectors. The annual mean indoor radon concentration in each measuring site was estimated from the four individual measurements with 3 months duration. The measuring period was from December 2008 to December 2009. The distribution of the results was nearly log-normal. The arithmetic and geometric mean values of the annual mean value of radon concentration were estimated to be 105 ± 84 and 84*/1.9 Bq m(-3), respectively. The annual effective dose due to indoor exposure to radon in the dwellings was estimated to be 2.1*/1.9 mSv y(-1).

  18. Exposure to indoor radon and natural gamma radiation in some workplaces at Algiers, Algeria.

    PubMed

    Aït Ziane, M; Lounis-Mokrani, Z; Allab, M

    2014-07-01

    Radon activity concentrations have been measured in 34 workplaces throughout Algiers nuclear research centre, in Algeria, during some periods between March 2007 and June 2013 using Electret ion chambers, nuclear tracks detectors and an AlphaGuard system. The indoor radon levels range from 2 to 628 Bq m(-3) with an average indoor concentration equals to 92 Bq m(-3), whereas the estimated outdoor radon concentrations range from 2 to 14 Bq m(-3) with an average value of 6 Bq m(-3). This study also focused on parameters affecting radon concentration levels such as floor number, ventilation and atmospheric parameters. Furthermore, the mean gamma rates have been measured in the different investigated locations and have been found to be varying between 33 and 3300 nSv h(-1). The annual effective dose for workers calculated using the appropriate equilibrium and occupancy factors is lower than the value recommended by International Commission on Radiological Protection in its Publication 103.

  19. 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.

  20. 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

  1. Characterization of an aerosol chamber for human exposures to endotoxin.

    PubMed

    Taylor, L; Reist, P C; Boehlecke, B A; Jacobs, R R

    2000-03-01

    The objective of this study was to develop and characterize an exposure chamber in which human subjects could be exposed to low dust concentrations carrying an endotoxin coating. An exposure chamber, dust dispersion method, and endotoxin characterization technique were developed for inhalation exposures. A 6.27 m3 exposure chamber was designed and constructed from cinder block, glass windows, and Plexiglas. Using an acetone adhesion process, Enterobacter agglomerans were adsorbed onto respirable cellulose particles to create the endotoxin aerosol. The size distribution of the endotoxin-treated particles was verified using light microscopy and cascade impactors. A dry powder dust generator was refined to consistently disperse small quantities of the aerosol into the chamber to maintain dust concentrations at approximately 250 micrograms/m3. Dust levels during the chamber exposures were monitored using a portable continuous aerosol monitor (PCAM). During initial exposure runs, PCAM monitoring stations were positioned at different locations within a 0.5-meter matrix to document mixing patterns. Total dust and cascade impactor samples were collected throughout each exposure period to characterize the chamber operating system and insure the mean airborne dust concentration fulfilled target levels. A one-factor analysis of variance at the 95 percent confidence interval illustrated that there was not a statistically significant difference in the mean dust concentration throughout the exposure runs compared to the individual runs. Together the consistency of the total dust filters, endotoxin concentrations, and aerosol-monitoring instrument were adequate to allow use of the chamber for experimental studies involving human volunteers.

  2. 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.

  3. Characterisation of an electronic radon gas personal dosemeter.

    PubMed

    Gründel, M; Postendörfer, J

    2003-01-01

    The monitoring of radon exposure at workplaces is of great importance. Up to now passive measurement systems have been used for the registration of radon gas. Recently an electronic radon gas personal dosemeter came onto the market as an active measurement system for the registration of radon exposure (DOSEman; Sarad GmbH, Dresden, Germany). In this personal monitor, the radon gas diffuses through a membrane into a measurement chamber. A silicon detector system records spectroscopically the alpha decays of the radon gas and of the short-lived progeny 218Po and 214Po gathered onto the detector by an electrical field. In this work the calibration was tested and a proficiency test of this equipment was made. The diffusion behaviour of the radon gas into the measurement chamber, susceptibility to thoron, efficiency, influence of humidity, accuracy and the detection limit were checked. PMID:14756187

  4. 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.

  5. 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.

  6. 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.

  7. Radon exposure at a radioactive waste storage facility.

    PubMed

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

    2014-06-01

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

  8. 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. PMID:24705248

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

    PubMed Central

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

    2003-01-01

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

  10. Residential radon exposure and lung cancer: an overview of published studies

    SciTech Connect

    Neuberger, J.S. )

    1991-01-01

    A possible link between presumed or measured household radon exposure and lung cancer is reviewed on the basis of published epidemiologic studies. Evidence of a link is reported as a result of studies in Sweden; findings are inconsistent elsewhere. A number of methodological problems were found. Many of the studies are ecological in design and are, therefore, primarily hypothesis generating. A number of studies lack any data on the number of lung cancers and are, therefore, difficult to evaluate. Some other studies provide results that are internally inconsistent. Of the case/control studies, there are many with minimal or no information on active and passive smoking, occupation, family history of cancer, and diet. The case/control studies are generally small in size and of low statistical power. Exposure classifications are nonstandardized, inconsistent in their findings, and often gross in their characterization of radon concentrations. Relatively few of the studies actually measured radon exposure. Some of the studies showed significant positive associations either with geological characteristics, water supply contamination, or house type. No significant associations were found with residence near uranium or radium processing waste. Where radon levels were measured, a relatively small percentage of studies found a statistically significant positive association with lung cancer. Overall, the evidence for an association between residential radon exposure and lung cancer is weak. There is a need for a more decisive case/control epidemiologic study of this problem.55 references.

  11. 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.

  12. 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.

  13. Estimating lung cancer mortality from residential radon using data for low exposures of miners

    SciTech Connect

    Lubin, J.H.; Tomasek, L.; Kunz, E.

    1997-02-01

    Some recent estimates of lung cancer risk from exposure to radon progeny in homes have been based on models developed from a pooled analysis of 11 cohorts of underground miners exposed to radon. While some miners were exposed to over 10,000 working level months (WLM), mean exposure among exposed miners was 162 WLM, about 10 times the exposure from lifetime residence in an average house and about three times the exposure from lifetime residence at the {open_quotes}action level{close_quotes} suggested by the U.S. Environmental Protection Agency. The extrapolation of lung cancer risk from the higher exposures in the miners to the generally lower exposures in the home is a substantial source of uncertainty in the assessment of the risk of indoor radon. Using the pooled data for the miners, analyses of lung cancer risk were carried out on data restricted to lower exposures, either <50 WLM or <100 WLM. In the pooled data, there were 115 lung cancer cases among workers with no occupational WLM exposure and 2,674 among exposed miners, with 353 and 562 lung cancer cases in miners with <50 WLM and <100 WLM, respectively. Relative risks (RRs) for categories of WLM based on deciles exhibited a statistically significant increasing trend with exposure in each of the restricted data sets. In the restricted data, there was little evidence of departures from a linear excess relative risk model in cumulative exposure, although power to assess alternative exposure-response trends was limited. Risk models based on the unrestricted data for miners provided an excellent fit to the restricted data, suggesting substantial internal validity in the projection of risk from miners with high exposures to those with low exposures. Estimates of attributable risk for lung cancer (10-14%) in the U.S. from residential radon based on models from the unrestricted data were similar to estimates based on the data for miners receiving low exposures. 34 refs., 2 figs., 7 tabs.

  14. Dose-dependent in vivo cell-cycle changes following radon progeny exposure

    SciTech Connect

    Johnson, N.F.; Carpenter, T.R.; Hickman, A.W.; Jaramillo, R.J.; Gurule, D.M.

    1994-11-01

    Exposures to low concentrations of alpha-emitting radon progeny are reported by the U.S. Environmental Protection Agency to be the second leading cause of lung cancer. Current risk estimates for lung cancer from the inhalation of radon progeny are based on data from underground uranium miners. To produce such risk estimates, calculations are based on several assumptions concerning exposure-response relationships rather than dose-response relationships. A better understanding of the mechanisms of interactions between alpha particles, the cells of the respiratory tract, and the progression toward cancer may validate the mathematical models used to derive risk estimates.

  15. Lung cancer in women and type of dwelling in relation to radon exposure

    SciTech Connect

    Svensson, C.; Pershagen, G.; Klominek, J.

    1989-04-01

    A case-control study based on interviews with 210 incident female lung cancer patients, 209 age-matched population controls, and 191 hospital controls was carried out in Stockholm county, Sweden. Radon measurements made in a sample of 303 dwellings, in which the study subjects had lived, showed that dwellings with ground contact had an average concentration of approximately 160 Bqm-3, twice the average concentration of other dwellings. A cumulated radon exposure index was calculated for each subject based on data from the interviews and the measurements. For the total group of lung cancer a relative risk (RR), adjusted for smoking, age, and degree of urbanization, of 1.8 (95% confidence interval: 1.2-2.9) and 1.7 (0.9-3.3) associated with ''intermediate'' and ''high'' exposure to radon was found. There was also a significant trend to a positive dose-response relationship (Ptrend = 0.03). For small cell cancer the corresponding figures for RRs were 1.9 (0.6-4.5) and 4.7 (1.5-14.2), respectively (Ptrend = 0.01). There seemed to be a positive interaction between radon exposure and smoking in relation to lung cancer. The findings indicate that domestic radon may be of importance for the induction of lung cancer, particularly for some histological types.

  16. 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

  17. [Radiation exposure and risk of radon in the room air of Swiss houses].

    PubMed

    Burkart, W

    1986-01-01

    The radioactive noble gas radon, a member of the natural decay chains of uranium and thorium, enters the indoor environment in regionally highly diverging amounts. Subsoil of dwellings, building materials and drinking water are the main sources. In Switzerland and in many other countries, exposure of the lung tissue to the short lived radon decay products is the most important component of the radiation dose of the general public. Annual doses in areas with crystalline rock of high uranium content may reach the limits set up for occupational exposure. However, a clear link between cumulative exposure to radon daughters and elevation of the lung cancer incidence exists only for underground miners. The majority of human epidemiological studies point to a linear dose effect relationship. The indoor radon levels are determined by geology, building materials and techniques, climate and behaviour of the occupants. Experiences from Scandinavia and the Northern parts of America clearly indicate the possibility of cost-efficient remedial measures to reduce indoor radon levels.

  18. Alternative assessment of exposure of uranium miners to radon and progeny using {sup 210}Pb in vivo measurements

    SciTech Connect

    Guilmette, R.A.; Snipes, M.B.; Hoover, M.D.

    1997-12-01

    Significant uncertainties exist in estimating uranium miners` exposure to radon and its radioactive progeny during their mining careers. These uncertainties are due in part to the limited number and poor quality of measurements of radon and radon progeny concentrations made in various uranium mines, particularly during the 1945 to 1960 time period during which radon levels were the highest because of ineffective ventilation in the mines. We hypothesize that a major contributor to the 30-fold variability noted in lung cancer risk factors for the 12 epidemiological studies done on uranium miners worldwide is due to exposure estimate bias among the different populations.

  19. 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.

  20. 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.

  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. PMID:25601905

  3. Thoron detection with an active Radon exposure meter--first results.

    PubMed

    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. PMID:24593342

  4. 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

  5. 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

  6. 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

  7. 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.

  8. 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.

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

    PubMed

    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

  10. 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.

  11. 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

  12. 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)

  13. 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)

  14. 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.

  15. 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.

  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. Intercomparison of active, passive and continuous instruments for radon and radon progeny

    SciTech Connect

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

    1995-12-31

    The DOE/OHER radon, thoron and progeny exposure and test facility was set up in 1993 to provide a well controlled, airtight and uniform environment. The new calibration chamber is the primary test facility at the Environmental Measurements Laboratory (EML), in which a large number of an diverse types of monitoring instruments can be accomodated for calibration, evaluation and intercomparison purposes. The test chamber is environmentally controlled for temperature and humidity. Monodispersed or polydispersed aerosols are generated to study radon and thoron progeny attachment and behavior and to investigate instrument performance under different conditions of exposure. Also, particle size measurements are performed to develop techniques for the assessment of the health risk from the inhalation of radon and thoron progeny. The results from the May 1995 intercomparison for active, passive and continuous instruments for radon and radon progeny are presented. Instruments that measure radon were represented by 13 participants with open face 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 4 participants that came in person to take part in the grab sampling methodology for measuring individual radon progeny and the potential alpha energy (PAEC). The results indicate that all the tested instruments that measure radon are in good standing. 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 PAEC (WL), appear to underestimate the potential risk from radon progeny when the concentration of particles onto which the radon progeny are attached is <5,000 cc{sup -1}.

  19. 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.

  20. Exposure to indoor radon and natural gamma radiation in some workplaces at Algiers, Algeria.

    PubMed

    Aït Ziane, M; Lounis-Mokrani, Z; Allab, M

    2014-07-01

    Radon activity concentrations have been measured in 34 workplaces throughout Algiers nuclear research centre, in Algeria, during some periods between March 2007 and June 2013 using Electret ion chambers, nuclear tracks detectors and an AlphaGuard system. The indoor radon levels range from 2 to 628 Bq m(-3) with an average indoor concentration equals to 92 Bq m(-3), whereas the estimated outdoor radon concentrations range from 2 to 14 Bq m(-3) with an average value of 6 Bq m(-3). This study also focused on parameters affecting radon concentration levels such as floor number, ventilation and atmospheric parameters. Furthermore, the mean gamma rates have been measured in the different investigated locations and have been found to be varying between 33 and 3300 nSv h(-1). The annual effective dose for workers calculated using the appropriate equilibrium and occupancy factors is lower than the value recommended by International Commission on Radiological Protection in its Publication 103. PMID:24711531

  1. [Case-control study of lung cancer and combined home and work radon exposure in the town of Lermontov].

    PubMed

    Pakholkina, O A; Zhukovskiĭ, M V; Iarmoshenko, I V; Lezhnin, V L; Vereĭko, S P

    2011-01-01

    Relation between the risk of lung cancer and combined home and work indoor radon exposure was studied on the example of the population of Lermontov town (Stavropol Region, Russia). The town is situated in the former uranium mining area. Case (121 lung cancer cases) and control (196 individuals free of lung cancer diagnosis) groups of the study included both ex-miners and individuals that were not involved in the uranium industry. Home and work radon exposures were estimated using archive data as well as contemporary indoor measurements. The results of our study support the conclusion about the effect of radon exposure on the lung cancer morbidity.

  2. Relation of radon exposure and tobacco use to lung cancer among tin miners in Yunnan Province, China

    SciTech Connect

    Qiao, Y.L.; Taylor, P.R.; Yao, S.X.; Schatzkin, A.; Mao, B.L.; Lubin, J.; Rao, J.Y.; McAdams, M.; Xuan, X.Z.; Li, J.Y. )

    1989-01-01

    We studied the relation of radon exposure and tobacco use to lung cancer among tin miners in Yunnan Province in the People's Republic of China. Interviews were conducted in 1985 with 107 living tin miners with lung cancer and an equal number of age-matched controls from among tin miners without lung cancer to obtain information on lung cancer risk factors including a detailed history of employment and tobacco use. Occupational history was combined with extensive industrial hygiene data to estimate cumulative working level months (WLM) of radon daughter exposure. Similar data were also used to estimate arsenic exposure for control in the analysis. Results indicate an increased risk of lung cancer for water pipe smoking, a traditional form of tobacco use practiced in 91% of cases and 85% of controls. The use of water pipes was associated with a twofold elevation in risk when compared with tobacco abstainers, and a dose-response relation was observed with increasing categories of pipe-year (dose times duration) usage. Estimated WLM of radon exposure varied from 0 to 1,761 among subjects but averaged 515 in cases versus only 244 in controls. Analyses indicated that the persons in the highest quarter of the radon exposure distribution had an odds ratio (OR) = 9.5 (95% confidence interval = 2.7-33.1) compared to persons without radon exposure after controlling for arsenic exposure and other potential confounders. Examination of duration and rate of radon exposure indicated higher risk associated with long duration as opposed to high rate of exposure. Cross-categorizations of radon exposure and tobacco use suggest greater risk associated with radon exposure than tobacco in these workers.

  3. Effects of acute radon progeny exposure on rat alveolar macrophage number and function

    SciTech Connect

    Johnson, N.F.; Newton, G.J.; Guilmette, R.A.

    1992-12-31

    Alveolar macrophages play a key role in removal and translocation of inhaled particles and have been shown to influence proliferation of Alveolar Type II cells and fibroblasts. The effect of radon progeny on alveolar macrophage number and function is not documented. Functional impairment of alveolar macrophages may be an ancillary event in the induction of pulmonary lesions and may also indicate dose to the peripheral lung. In our study, rats were exposed to 1000 working level months (WLM) of radon progeny over a 3- to 5-h period, with a vector aerosol of environmental tobacco smoke. Groups of animals were sacrificed, and the lungs were lavaged immediately after exposure and on days 2, 18, 16, 21 and 29 after exposure. The numbers and viabilities of the lavaged macrophages were determined. Cytological preparations were made to determine the number of binucleated/multinucleated macrophages and macrophages containing micronuclei. The DNA content was measured flow-cytometrically using Hoechst 33342, and phagocytosis was assayed by determining the uptake of fluorescent microspheres. The numbers and viabilities of macrophages recovered from exposed animals were similar to the values measured for control animals. There was no evidence of an inflammatory reaction during any period after radon progeny exposure. Nuclear atypia, evidenced by increases in the number of binucleated cells and cells with micronuclei, occurred in animals 8 days after exposure, and this response peaked at 21 days after exposure. The phagocytic capability of the alveolar macrophages was not significantly affected at any time point after exposure. These results show that there was little functional impairment of alveolar macrophages in rats after acute radon-progeny exposure; however, there was long-standing interference with cell division, resulting in binucleated and micronucleated macrophages.

  4. Estimating lung cancer mortality from residential radon using data for low exposures of miners.

    PubMed

    Lubin, J H; Tomásek, L; Edling, C; Hornung, R W; Howe, G; Kunz, E; Kusiak, R A; Morrison, H I; Radford, E P; Samet, J M; Tirmarche, M; Woodward, A; Yao, S X

    1997-02-01

    Some recent estimates of lung cancer risk from exposure to radon progeny in homes have been based on models developed from a pooled analysis of 11 cohorts of underground miners exposed to radon. While some miners were exposed to over 10,000 working level months (WLM), mean exposure among exposed miners was 162 WLM, about 10 times the exposure from lifetime residence in an average house and about three times the exposure from lifetime residence at the "action level" suggested by the U.S. Environmental Protection Agency. The extrapolation of lung cancer risk from the higher exposures in the miners to the generally lower exposures in the home is a substantial source of uncertainty in the assessment of the risk of indoor radon. Using the pooled data for the miners, analyses of lung cancer risk were carried out on data restricted to lower exposures, either <50 WLM or <100 WLM. In the pooled data, there were 115 lung cancer cases among workers with no occupational WLM exposure and 2,674 among exposed miners, with 353 and 562 lung cancer cases in miners with <50 WLM and <100 WLM, respectively. Relative risks (RRs) for categories of WLM based on deciles exhibited a statistically significant increasing trend with exposure in each of the restricted data sets. In the restricted data, there was little evidence of departures from a linear excess relative risk model in cumulative exposure, although power to assess alternative exposure-response trends was limited. The general patterns of declining excess RR per WLM with attained age, time since exposure and exposure rate seen in the unrestricted data were similar to the patterns found in the restricted data. Risk models based on the unrestricted data for miners provided an excellent fit to the restricted data, suggesting substantial internal validity in the projection of risk from miners with high exposures to those with low exposures. Estimates of attributable risk for lung cancer (10-14%) in the U.S. from residential radon

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

    NASA Astrophysics Data System (ADS)

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

    2014-02-01

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

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

    PubMed

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

    2014-02-01

    Computer software for calculation of the sensitivity of a CR-39 detector closed in a diffusion chamber to radon is described in this work. The software consists of two programs, both written in the standard Fortran 90 programming language. The physical background and a numerical example are given. Presented software is intended for numerous researches in radon measurement community. Previously published computer programs TRACK_TEST.F90 and TRACK_VISION.F90 [D. Nikezic and K. N. Yu, Comput. Phys. Commun. 174, 160 (2006); D. Nikezic and K. N. Yu, Comput. Phys. Commun. 178, 591 (2008)] are used here as subroutines to calculate the track parameters and to determine whether the track is visible or not, based on the incident angle, impact energy, etching conditions, gray level, and visibility criterion. The results obtained by the software, using five different V functions, were compared with the experimental data found in the literature. Application of two functions in this software reproduced experimental data very well, while other three gave lower sensitivity than experiment. PMID:24593338

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

    SciTech Connect

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

    2014-02-15

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

  8. Risk assessment of exposure to waterborne and airborne radon-222 in Illinois. Final report

    SciTech Connect

    Hallenbeck, W.H.

    1987-12-01

    This study analyzed epidemiological and experimental animal studies in order to develop exposure-response relationships for radon-induced cancer. These relationships were used to estimate lifetime risks and annual excess cases based on the available waterborne and airborne data for Illinois. Exceedances of the USEPA action level of 4pCi/l occurred in 13% of 303 first-floor measurements and 43% of 1094 basement measurements. For waterborne radon, the highest lifetime risk of cancer mortality associated with an Illinois groundwater-based drinking water system was estimated to be 4 x 104. The number of excess cases of fatal cancer generated per year in Illinois was estimated to be about six. For airborne radon, a tentative value of 0.9 pCi/l (for first floors), derived from the limited existing data, was used to estimate the average lifetime lung-cancer mortality risk and the number of excess cases of fatal lung cancer generated per year. The average lifetime lung-cancer mortality risk was estimated to be 0.0048, and the annual number of excess cases of fatal lung cancer was estimated to be 784. Due to the nature of the underlying exposure-response relationships for radon-induced cancer, the values presented most likely represent upper-bound estimates.

  9. The new risk estimates and exposures to radon in high grade uranium mines

    SciTech Connect

    Brown, L.D. )

    1992-09-01

    The DS86 dosimetry used by the Radiation Effects Research Foundation, in re-evaluating radiation exposure risks from the atom bomb survivor lifespan studies, has led directly to a significant reduction in the maximum permissible dose recommended by the International Commission on Radiological Protection. In the case of uranium miners the contribution to the total dose resulting from the inhalation of radon daughters continues to be assessed in accordance with the procedures recommended in ICRP Report 47, which means that there has been no change in the maximum permissible radon daughter exposure limit. ICRP intends to review this situation once the new report of their task force on lung dosimetry has been adopted. This paper suggests that the direct epidemiological data on the risks of radon daughter inhalation is more satisfactory than indirect estimates of risk based on a lung dosimetry model, and that this direct evidence does not justify any increase in the presently accepted risk factor associated with radon daughter inhalation.

  10. Exposure to radon progeny, tobacco use and lung cancer in a case-control study in Southern China

    SciTech Connect

    Shu Xiang Yao; Fu Ming Zhang; Lubin, J.H.; Boice, J.D. Jr.; Blot, W.J.; You Lin Qiao; Jun Yao Li; Shu Kan Cai

    1994-06-01

    A case-control study of lung cancer in underground tin miners in southern China was conducted to examine the interplay between exposure to radon progeny and tobacco use. A total of 460 incident cases and 1,043 controls were evaluated. Among the exposed, mean radon progeny exposures were 600 and 427 working level months (WLM) for cases and controls, respectively. The excess relative risk per WLM (ERR/WLM) was 0.28% overall, with a 95% confidence interval of 0.1-0.6%, similar to the estimate from a cohort study in a related population of underground miners. The established patterns of lung cancer associated with radon were seen; the ERR/WLM decreased with attained age and time since last exposure. Conditional on total exposure, risk was highest for exposures delivered at a low rate. The ERR/WLM did not differ significantly among current and former smokers or within categories of time since last exposure. The relative risk relationship between exposure to radon progeny and tobacco use was consistent with a multiplicative model, but the best-fitting model was intermediate between additive and multiplicative; an additive association was rejected. Adjustment for exposure to inorganic arsenic, a known lung carcinogen, reduced the estimate of the ERR/WLM from 0.86% to 0.28%. The ERR/WLM estimate was homogeneous across subgroups defined by workers not exposed to arsenic and quartiles of cumulative arsenic exposure. Although squamous cell carcinoma was the predominant cell type, small cell and adenocarcinoma histologies appeared more strongly associated with exposure to radon progeny. The finding of a stronger trend with exposure with small cell carcinomas and adenocarcinomas, compared to squamous cell carcinomas, occurred primarily at younger ages at diagnosis. Finally, the risk of lung cancer was higher if exposure to radon progeny and tobacco use occurred together than if the exposure to radon progeny entirely preceded tobacco use. 24 refs., 3 figs., 8 tabs.

  11. Canadian lung cancer relative risk from radon exposure for short periods in childhood compared to a lifetime.

    PubMed

    Chen, Jing

    2013-05-08

    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.

  12. 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

  13. 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

  14. 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)).

  15. Indoor radon

    SciTech Connect

    Rabkin, M.A.; Bodansky, D.

    1988-12-31

    The first awareness of radon as a health hazard came from observations of increased lung cancer incidence among uranium and other miners. During the past decade there has been increasing recognition of the importance of radon in the indoor environment as well. Extrapolations from radon exposures in mines to those in homes indicate that radon will cause a significant number of lung cancer deaths among the general population if its effects are linearly proportional to the magnitude of the exposure. For example, in the United States roughly 5000 to 20,000 lung cancer deaths per year are now attributed to indoor radon. Consistent with this, the effective dose equivalent from indoor radon is larger than the dose from any other radiation source for most people in temperate climates. Radon is a noble gas and can diffuse freely through the air. The most important isotope of radon, Rn-222, is produced in the alpha-particle decay of Ra-226, which is present in all soil and rock as a product of the U-238 decay series. In consequence, radon is present in both the outdoor and indoor environments, primarily due to its escape from the soil into the open air or into houses. The indoor concentrations are usually much higher than the outdoor concentrations, because the radon that enters into houses escapes relatively slowly. 120 refs., 12 tabs.

  16. 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

  17. 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.

  18. 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. PMID:9470322

  19. Indoor radon.

    PubMed

    Polpong, P; Bovornkitti, S

    1998-01-01

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

  20. 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.

  1. Real-time measurement of individual occupational radon exposures in tombs of the Valley of the Kings, Egypt.

    PubMed

    Gruber, E; Salama, E; Rühm, W

    2011-03-01

    The active radon exposure meter developed recently at the German Research Center for Environmental Health (Helmholtz Zentrum München) was used to measure radon concentrations in 12 tombs located in the Valley of the Kings, Egypt. Radon concentrations in air between 50 ± 7 and 12 100 ± 600 Bq m(-3) were obtained. The device was also used to measure individual radon exposures of those persons working as safeguards inside the tombs. For a measurement time of 2-3 d, typical individual radon exposures ranged from 1800 ± 400 to 240 000 ± 13 000 Bq h m(-3), depending on the duration of measurement and radon concentration in the different tombs. Based on current ICRP dose conversion conventions for workers and on equilibrium factors published in the literature for these tombs, individual effective dose rates that range from 1.5 ± 0.3 to 860 ± 50 µSv d(-1) were estimated. If it is assumed that the climatic conditions present at the measurement campaign persist for about half a year, in this area, then effective doses up to ∼ 66 mSv could be estimated for half a year, for some of the safeguards of tombs where F-values were known. To reduce the exposure of the safeguards, some recommendations are proposed. PMID:21183552

  2. A further study of the (CR LR) difference technique for retrospective radon exposure assessment

    NASA Astrophysics Data System (ADS)

    Nikezic, D.; Yip, C. W. Y.; Leung, S. Y. Y.; Leung, J. K. C.; Yu, K. N.

    2006-12-01

    The (CR-LR) difference technique, based on the CR-39 and LR 115 detectors, for the determination of implanted 210Po in glass after deposition of short-lived radon progeny, was analyzed in details in this paper. The sensitivities of both detectors were calculated using the Monte Carlo method with V functions particularly derived in our previous works for the detectors used in the present experiments. The dependency of the sensitivity ratio on the removed layer of both detectors was determined and verified experimentally. The simulated sensitivity ratios correlate well with the experimental ones. A major finding of the present work is that the sensitivity ratio between the CR-39 and LR 115 detectors depends only weakly on the ratio between the 238U and 232Th concentrations in the glass samples. This is crucial for the application of the (CR-LR) difference technique for retrospective radon exposure assessments, since measurements of the 238U and 232Th concentrations in the relatively small real-life glass samples will make the retrospective radon exposure assessments impractical.

  3. Tests of the linear-no threshold theory for lung cancer induced by exposure to radon

    SciTech Connect

    Cohen, B.L. ); Colditz, G.A. )

    1994-01-01

    The linear theory used to extrapolate the cancer risk of radon exposure from high levels where direct data are available to low levels encountered in homes is tested by comparing lung cancer rates, m, and average radon levels, r, in numerous U.S. states and counties. It is shown that most problems normally associated with ecological studies do not apply here. The data shown a very strong tendency for lung cancer rates, corrected for smoking prevalence (S), to decrease with increasing r, in sharp contrast to the opposite behavior predicted by the theory. It is shown that even a perfect negative r-S correlation cannot explain this discrepancy. Actual r-S correlations are only a few percent. Several other possible explanations for the discrepancy are explored, but none reduce it by more than about 25%. 39 refs., 2 figs., 6 tabs.

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

    SciTech Connect

    Andre, H.M.

    1982-10-01

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

  5. 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

  6. 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.

  7. 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.

  8. Effects of air exchange property of passive-type radon-thoron discriminative detectors on performance of radon and thoron measurements.

    PubMed

    Omori, Y; Janik, M; Sorimachi, A; Ishikawa, T; Tokonami, S

    2012-11-01

    Pairs of diffusion chambers with different air exchange rates are used in a large-scale survey to determine radon and thoron, separately. When they are enclosed in radon-proof bags for keeping after the exposure, since radon does not escape out immediately from the low-diffusion chamber, it leads to further exposure in the bags and disturbs the estimation of radon and thoron concentrations. In this study, the effects of the different air exchange properties of the radon-thoron discriminative detectors with CR-39 chips on the estimations of radon and thoron concentrations were investigated. The commercially available and frequently used detectors, Raduet, are examined in this study. The result shows that radon escapes out in 10 h. When degassing is not enough after the exposure in a calibration experiment or high-background radiation area, the residual radon causes the overestimation of the radon concentration and increase in the uncertainty in the thoron concentration, i.e. a low-performance quality of radon and thoron measurements.

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

    PubMed

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

    2015-11-01

    Accurate measurement of radon and its progenies is the basis to control the radon dose and reduce the risk of lung cancer caused. The precise calibration of measuring instrument is an important part of the quality control of measurements of the concentration of radon and radon progenies. To establish Chinese national standards and realise reliable calibrations of measuring instrument for radon and its progenies, a radon chamber with regulation capability of environmental parameters, aerosol and radon concentrations was designed and constructed at National Institute of Metrology (NIM). The chamber has a total volume of ∼20 m(3) including an exposure volume of 12.44 m(3). The radon concentration can be controlled from 12 Bq m(-3) to the maximum of 232 kBq m(-3). The regulation range of temperature, relative humidity and aerosol are 0.66 -44.39°C, 16.4 -95 %RH and 10(2) -10(6) cm(-3), respectively. The main advantages of the NIM radon chamber with respect to maintaining a stable concentration and equilibrium factor of radon progenies in a wide range through automatic regulation and control of radon and aerosol are described. PMID:25948838

  10. 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.

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

    PubMed

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

    1990-01-01

    Hypoxia was studied in 12 men during 63-h exposures to 17 and 13% O2, with the subjects serving as their own controls by repeating the measurements in 21% O2. All test atmospheres were contaminated with 0.9% CO2 to simulate the condition of living aboard submarines. The mean SaO2's were 97-98% in all conditions of 21% O2, 96% in 17% O2 (n.s.), and 92% in 13% O2 (P less than 0.05). The blood concentrations of 2,3-diphosphoglycerate were elevated in 13 and 17% O2 (P less than 0.05). Seventeen percent O2 did not cause significant symptoms of environmental stress; however, 13% O2 caused symptoms of acute mountain sickness in 5 of 12 men. In the last 7 h of exposure to 17% O2, reduction of the barometric pressure to 576 Torr reduced the ambient PO2 to 98 Torr (similar to the PO2 of 13% O2 at normobaric pressure). This induced symptoms of acute mountain sickness in 3 of 11 men. All symptomatology and physiologic changes were reversed during recovery in 21% O2. Monitoring devices indicated the presence of volatile organic contaminants at a mean concentration of 6.1 ppm in the chamber atmosphere. Combustion tests in the occupied chamber showed that flame propagation was retarded by lowering the O2 concentration from 21 to 13-17%. We conclude that men can live comfortably in a normobaric, flame-retardant atmosphere consisting of 17% O2-0.9% CO2-6.1 ppm volatile organic compounds-balance N2. PMID:2107616

  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. 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.

  15. 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.

  16. 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

  17. 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

  18. 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.

  19. A Muon Exposure in the Tohoku High Resolution Bubble Chamber

    SciTech Connect

    Chen, A.; Shapire, A.; Widgoff, M.; Childress, S.; Murphy, T.; Alyea, E.D.; Mao, C.; Tai, Y.; Wang, S.; Wu, Y.; Xu, S.W.; /IHEP /MIT /Tohoku U. /Tohoku Gakuin U.

    1986-01-01

    The authors would like to propose an experiment to investigate muon induced interactions in the Tohoku freon bubble chamber, a high resolution 4{pi} detector. The Tohoku bubble chamber is located in Lab F on the neutrino beam line. The NT test beam line, which passes 4.5 meters east of the bubble chamber, has carried a muon beam to Lab F in the past. it appears possible to bend this beam to the west sufficiently to send muons of approximately 200 GeV to the present position of the Tohoku chamber. A bubble chamber experiment will have better systematics than a comparable muons cattering experiment using counters, but will have lower statistics. With the chamber, direct observation of neutral strange particle and charm particle production will make possible a unique clean study of the virtual photon interactions involved.

  20. 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.

  1. 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.

  2. 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.

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

    USGS Publications Warehouse

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

    1993-01-01

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

  4. Development of exposure assessment method with the chamber

    NASA Astrophysics Data System (ADS)

    Kato, N.; Koyama, Y.; Yokoyama, H.; Matsui, Y.; Yoneda, M.

    2015-05-01

    This study aims at developing the measurement method of nanoparticle concentration and at getting a representative value of nanoparticle uniform concentration due to chamber ventilation. We conducted a chamber equipped with HEPA filter and control the background nanoparticles concentration by using an adequate ventilation. Then, we used generator to evaluate concentration in the chamber uniformity. We measured background value and source counts at the particle size distribution by SMPS. In addition, we performed numerical analysis with CFD model OpenFoam. As results, we found that there is no aggregate in experimental conditions in this study. Though we confirmed that it is difficult to uniformalise nanoparticle concentration, However we also found simulation results showed higher reproducibility. Therefore, we could assess nanoparticle size distribution and concentration in our chamber at this stage.

  5. 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.

  6. Exposure of population from residential radon: a case study for district Hattian, Azad Kashmir, Sub-Himalayas, Pakistan.

    PubMed

    Rafique, M; Rahman, S U; Matiullah

    2012-11-01

    Indoor air quality has acquired considerable importance in recent years. Tighter buildings with poorer ventilation systems have led towards higher levels of indoor air pollution. Radon is considered to be most significant perilous gas among the various air contaminants found in the residential environment. To determine the risk posed by residential radon exposure, a survey was carried out in the Hattian district of the state of Azad Jammu and Kashmir, Pakistan. In this context, 160 houses were carefully selected for the installation of CR-39-based National Radiological Protection Board-type detectors installation. After exposing the CR-39 detectors for a period of 90 d, they were etched in 6 M chemical solution of sodium hydroxide at a temperature of 80°C for a period of 16 h. The detectors were read under an optical microscope and observed track densities were converted into the indoor radon concentration using a calibration factor of 2.7 tracks cm(-2) h(-1) per kBqm(-3). For the current study, observed radon concentrations ranged from 35 to 175 Bqm(-3), whereas the mean annual effective radon doses received by the inhabitants of the area ranged from 0.88 ± 0.12 to 4.41 ± 0.20 mSv with an average value of 2.62 ± 0.12 mSv. These reported values are less than the limits (standards) recommended by the different world organisations.

  7. Radon exposure in the thermal spas of Lesvos Island--Greece.

    PubMed

    Vogiannis, E; Nikolopoulos, D; Louizi, A; Halvadakis, C P

    2004-01-01

    The aim of this work is to study the exposure due to radon to bathers and personnel in the spas of Lesvos Island under a specific use pattern. 222Rn concentrations in the supplying water were measured during a long time period. Variations in indoor 222Rn, attached and unattached progenies, and influence of the ambient atmosphere were thoroughly analysed during bath treatment for the purpose of investigating a consequent probable short-term health impact. Concentration peaks both for 222Rn and PAEC were found to appear during bathtubs filling. These peaks considered imposing an additional short-term radiation burden for spa users. The additional doses delivered to bathers during bath treatment were found to be very low and for personnel did not exceed the value of 5 mSv per year.

  8. Probability of causation for lung cancer after exposure to radon progeny: A comparison of models and data

    SciTech Connect

    Chmelevsky, D.; Barclay, D.; Kellerer, A.M. |; Tomasek, L.; Kunz, E.; Placek, V.

    1994-07-01

    The estimates of lung cancer risk due to the exposure to radon decay products are based on different data sets from underground mining and on different mathematical models that are used to fit the data. Diagrams of the excess relative rate per 100 working level months in its dependence on age at exposure and age attained are shown to be a useful tool to elucidate the influence that is due to the choice of the model, and to assess the differences between the data from the major western cohorts and those from the Czech uranium miners. It is seen that the influence of the choice of the model is minor compared to the difference between the data sets. The results are used to derive attributable lifetime risks and probabilities of causation for lung cancer following radon progeny exposures. 23 refs., 9 figs.

  9. 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.

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

    PubMed

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

    2012-08-01

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

  11. A new method specifically designed to expose cells isolated in vitro to radon and its decay products.

    PubMed

    Petitot, F; Morlier, J P; Debroche, M; Pineau, J F; Chevillard, S

    2002-06-01

    A system was set up to provide direct exposure of cells cultured in vitro to radon and its decay products. Radon gas emanating from a uranium source was introduced at a measured concentration in a closed 10-m(3) exposure chamber. Cells were cultured on the microporous membrane of an insert that was floating over the culture medium in a six-well cluster plate. Plates with cells were placed in an open thermoregulated bath within the chamber. Under these conditions, cells were irradiated by direct deposition of radon and radon decay products. During exposure, all parameters, including radon gas concentrations, decay product activities, and potential alpha-particle energy concentrations, were determined by periodic air-grab samplings inside the chamber. The energy spectrum of deposited decay products was characterized. An estimation of alpha-particle flux density on the area containing cells was performed using CR-39 detector films that were exposed in cell-free wells during the cell exposure. The number of alpha-particle traversals per cell was deduced both from the mean number of CR-39 tracks per surface unit and from measurements of entire cells or nuclear surfaces. This paper describes the design of experiment, the dosimetry of radon and radon decay product, and the procedures for aerosol measurements. Our preliminary data show the usefulness of the in vitro cell culture approach to the study of the early cellular effects of radon and its decay products.

  12. 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.

  13. 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.

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

    NASA Astrophysics Data System (ADS)

    Mishra, Rosaline; Sapra, B. K.; Mayya, Y. S.

    2014-02-01

    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/m3 whereas that for DRPS is 1 Bq/m3, 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.

  15. Indoor radon in a Spanish region with different gamma exposure levels.

    PubMed

    Quindós, L S; Fernández, P L; Sainz, C; Fuente, I; Nicolás, J; Quindós, L; Arteche, J

    2008-10-01

    In the beginning of 1990s within the framework of a national radon survey of more than 1500 points, radon measurements were performed in more than 100 houses located in Galicia region, in the Northwest area of Spain. The houses were randomly selected only bearing in mind general geological aspects of the region. Subsequently, a nationwide project called MARNA dealt with external gamma radiation measurements in order to draw a Spanish natural radiation map. The comparison in Galicia between these estimations and the indoor radon levels previously obtained showed good agreement. With the purpose of getting a confirmation of this relationship and also of creating a radon map of the zone, a new set of measurements were carried out in 2005. A total of 300 external gamma radiation measurements were carried out as well as 300 measurements of 226Ra, 232Th and 40K content in soil. Concerning radon, 300 1-m-depth radon measurements in soil were performed, and indoor radon concentration was determined in a total of 600 dwellings. Radon content in soil gave more accurate indoor radon predictions than external gamma radiation or 226Ra concentration in soil.

  16. [The radon exposure in mine: risk evaluation, risk assessment and health effects].

    PubMed

    Coggiola, M; Scielzo, G; Baracco, A; Perrelli, F; Pribytkova, Z

    2011-01-01

    In mining sector, the natural presence of radon determines an exposition which deserves substantive consideration. The results of radon measure from '90 years in a talc mining show levels of radon below to the threshold limit of 400 Bq/m3, values influenced from air forced systems. The epidemiologic studies updated in a cohort of talc workers between 1946 and 1995 showed no excess for lung cancer mortality. No excess was found for lung cancer mortality in miners exposed to low dose of radon. PMID:23393887

  17. Lung exposure from inhalation of radon progeny: Calculated from in vivo measurements of {sup 210}Pb in the skull

    SciTech Connect

    Laurer, G.R.; Cohen, N.; Estrada, J.J.S.

    1999-04-01

    To calculate the radiation dose to the lungs from the inhalation of radon and its short-lived progeny, an accurate estimate of cumulative exposure is necessary. In this preliminary study, the content of {sup 210}Pb in the skeleton is used to obtain a measure of integrated exposure to the lungs of people living in homes with above average concentrations of radon. Measurements of skeletal {sup 210}Pb made in vivo allow the exposed individuals to become, in effect, their own samplers and dosimeters through the normal physical and physiological processes of inhalation, deposition, and retention. {sup 210}Pb measurements have been made on 40 subjects whose homes have above average levels of radon. These data are used to obtain their cumulative lung exposures, defined as RLM (Respiratory Level Months). RLM is calculated from the numbers of atoms of RaA, RaB, and RaC,C{prime} deposited in their respiratory systems over the time periods lived in the surveyed homes. The RLM values obtained are not significantly different than conventional WLM exposures calculated for the same time periods.

  18. Estimated risk from exposure to radon decay products in US homes

    SciTech Connect

    Nero, A.V. Jr.

    1986-05-01

    Recent analyses now permit direct estimation of the risks of lung cancer from radon decay products in US homes. Analysis of data from indoor monitoring in single-family homes yields a tentative frequency distribution of annual-average /sup 222/Rn concentrations averaging 55 Bq m/sup -3/ and having 2% of homes exceeding 300 Bq m/sup -3/. Application of the results of occupational epidemiological studies, either directly or using recent advances in lung dosimetry, to indoor exposures suggests that the average indoor concentration entails a lifetime risk of lung cancer of 0.3% or about 10% of the total risk of lung cancer. The risk to individuals occupying the homes with 300 Bq m/sup -3/ or more for their lifetimes is estimated to exceed 2%, with risks from the homes with thousands of Bq m/sup -3/ correspondingly higher, even exceeding the total risk of premature death due to cigarette smoking. The potential for such average and high-level risks in ordinary homes forces development of a new perspective on environmental exposures.

  19. 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.

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

    PubMed

    Madas, Balázs G

    2016-07-01

    Investigating the health effects of low doses of ionizing radiation is considered to be one of the most important fields in radiological protection research. Although the definition of low dose given by a dose range seems to be clear, it leaves some open questions. For example, the time frame and the target volume in which absorbed dose is measured have to be defined. While dose rate is considered in the current system of radiological protection, the same cancer risk is associated with all exposures, resulting in a given amount of energy absorbed by a single target cell or distributed among all the target cells of a given organ. However, the biological effects and so the health consequences of these extreme exposure scenarios are unlikely to be the same. Due to the heterogeneous deposition of radon progeny within the lungs, heterogeneous radiation exposure becomes a practical issue in radiological protection. While the macroscopic dose is still within the low dose range, local tissue doses on the order of Grays can be reached in the most exposed parts of the bronchial airways. It can be concluded that progress in low dose research needs not only low dose but also high dose experiments where small parts of a biological sample receive doses on the order of Grays, while the average dose over the whole sample remains low. A narrow interpretation of low dose research might exclude investigations with high relevance to radiological protection. Therefore, studies important to radiological protection should be performed in the frame of low dose research even if the applied doses do not fit in the dose range used for the definition of low doses. PMID:27218294

  1. 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.

  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 facility for studying the carcinogenic and synergistic effects of radon daughters and other agents in rodents

    SciTech Connect

    Strong, J.C.; Walsh, M.

    1992-12-31

    Although there is evidence to link lung cancer with radon exposures in miners, studies have not yet adequately demonstrated a link at domestic levels of exposure. Induction of cancer in animals after acute exposure to high levels of radon and radon daughters has been investigated by several laboratories. It is our intention to study the effects of radon and its daughters on rodents following both acute and chronic exposure. The studies will be extended to investigate the effects of other carcinogens in association with radon daughters. We will describe a facility in which rodents can be exposed continuously to radon and its daughters for periods of up to several months. The facility consists of two exposure chambers with closed air circuits which are operated independently of each other. Aerosol generators provide controlled vector aerosols onto which radon daughters can attach. Particular attention has been paid to accurate measurements of the concentrations of radon gas and of individual radon daughters. Techniques have also been developed for measuring the {open_quotes}unattached{close_quotes} fraction, the activity size distribution of individual daughters, and the potential alpha energy. The environment within the facility will be adjusted to be comparable to that found in dwellings with regard to condensation nucleus concentration, {open_quotes}unattached{close_quotes} fraction, equilibrium factor, and activity size distribution. Other vapors and aerosols, such as tobacco smoke, can be introduced into one of the air circuits to study the combined effects of radiation and toxic chemical agents.

  4. 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.

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

    SciTech Connect

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

    1982-02-01

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

  6. Passive, integrated measurement of indoor radon using activated carbon.

    PubMed

    George, A C

    1984-04-01

    Activated carbon canisters were tested to determine their adsorption and retention characteristics for radon. Our tests conducted indoors under typical conditions of temperature and relative humidity indicate that simple, inexpensive and maintenance-free passive devices containing 150-200 g of activated carbon can measure radon conveniently and adequately. The amount of radon absorbed in the collector is determined by counting the gamma rays from the decay products of radon. The lower limit of detection for radon is 0.2 pCi/l. for an exposure of 72 hr. Greater sensitivity can be obtained with larger counting systems and devices containing carbon with more surface area. Tests in a residential building and in a test chamber indicate that the measured radon in the canister is proportional to the mean concentration of radon during the period of exposure when correction for relative humidity is made. For practical situations encountered indoors, the device yields results accurate to within +/- 20%. Results from field measurements indicate that the use of the device is feasible.

  7. 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.

  8. Radon in Wisconsin.

    PubMed

    Weiffenbach, C; Anderson, H A

    2000-11-01

    Owners of about 15% to 20% of the homes in Wisconsin have tested their indoor air for the carcinogenic gas radon. Five percent to 10% of homes have year-average main-floor radon levels that exceed the US Environmental Protection Agency (EPA) exposure guideline, and they are found in most regions of the state. Attempting to retroactively seal foundations to keep radon from the ground out of a home is largely ineffective. However, a soil-depressurization radon mitigation system is highly effective for existing houses, and new homes can easily be built radon-resistant. As the number of homeowners obtaining needed repairs increases, significant lung cancer risk reduction is being achieved in a voluntary, non-regulatory setting. In coming years, as radon in community drinking water supplies becomes regulated under the federal 1996 Safe Drinking Water Act, the "multimedia" option of the act may result in additional attention to mitigation of radon in indoor air. PMID:11149257

  9. Genetic effects of chronic radon exposure in northern pocket gophers (Thomomys talpoides)

    SciTech Connect

    McMillen, C.C.; McBee, K.; Hafner, D.J.

    1995-12-31

    This study examined effects on genetic organization of a chronic stressor, radon, in a population of Thomomys talpoides living in radon-rich soils in the Jemez Mountains of New Mexico compared to five populations living in soils with no measurable amounts of radon. Karyology showed no differences in standard metaphase chromosomal structure among populations. Flow cytometric analyses showed significant populational differences in mean G1 peak position but these differences were less than intraspecific differences previously described for gophers. Allozymic studies revealed lower mean heterozygosity levels in all populations than have been previously reported in the same geographic area. Cluster analysis using Roger`s genetic similarity coefficients separated the radon-exposed population from the unexposed populations; however, this suggests the possibility of adaptive biochemical differentiation in this population.

  10. 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. PMID:23798709

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

    PubMed

    Abbasi, A; Mirekhtiary, F

    2013-12-01

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

  12. Nucleation and evolution of ultrasonic cavitation in a rotating exposure chamber.

    PubMed

    Miller, D L; Williams, A R

    1992-08-01

    The nucleation and progression of ultrasonic cavitation in a rotating exposure chamber were investigated by observing hemolysis of a 0.5% suspension of erythrocytes. Bursts of 1.6 MHz ultrasound beams of 11 W/cm2 spatial peak intensity were synchronized with the rotation to aim the bursts down the axis of a cylindrical chamber. Cavitational hemolysis always occurred in fresh phosphate buffered saline (PBS) solution, but cavitation incidence declined to 38% in 4 day old PBS. The amount of hemolysis for 11 ms or 44 ms bursts with 60 rpm rotation increased in proportion to the number of bursts. Hemolysis was found above a minimum burst duration of 5.5 to 8.3 ms in the normal 2 cm chamber. This did not appear to change for 1 cm or 4 cm chamber lengths, but it did change to about 2.2 ms and about 44 ms for over- and undersaturated gas conditions, respectively. Off-times associated with rotation speeds of 15 to 30 rpm reduced the effectiveness of the cavitation, and addition of fixed cells at only 0.01% to 0.02% greatly reduced the hemolysis. For this ultrasonic exposure system, several thousand bubbles, possibly generated from as few as one cavitation nucleus, move across the chamber at up to 10 m/s, each lysing a few hundred cells, and then are cycled back to the front of the chamber by the rotation to reinitiate the cavitation on the next burst.

  13. Radiological risk assessment of environmental radon

    NASA Astrophysics Data System (ADS)

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

    2013-11-01

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

  14. Radiological risk assessment of environmental radon

    SciTech Connect

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

    2013-11-27

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

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

    NASA Astrophysics Data System (ADS)

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

    2015-05-01

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

  16. 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

  17. 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

  18. 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.

  19. 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

    2015-11-01

    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

  20. 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

  1. 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.

  2. Performance of NIRS Thoron Chamber System

    NASA Astrophysics Data System (ADS)

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

    2008-08-01

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

  3. Seasonal changes in radon concentrations in buildings in the region of northeastern Poland.

    PubMed

    Karpińska, Maria; Mnich, Zenon; Kapała, Jacek

    2004-01-01

    In this study, seasonal observations of radon concentration changes inside buildings carried out in the northeastern region of Poland is presented. One-year measurements of radon concentrations were performed in chosen buildings. The integral method of Cr-39 trace detectors in diffusive chambers was used. Mean values of radon concentrations were determined in monthly, 2-, 3-, 6-month, and annual observations. The fraction of a mean annual concentration of the value obtained in a shorter observation was calculated. Monthly concentration values were from about 0.2 to 14.9 of the annual mean. All buildings revealed seasonal fluctuation of radon concentration. Negative correlation of indoor radon concentration in the buildings and the mean temperature outside was observed in most examined buildings. The lowest coefficient range, determining which part of the annual mean value would be obtained in the 6-month observation, was gained for exposure begun in April or October.

  4. Mechanistic study on lung cancer mortality after radon exposure in the Wismut cohort supports important role of clonal expansion in lung carcinogenesis.

    PubMed

    Zaballa, I; Eidemüller, M

    2016-08-01

    Lung cancer mortality after radon exposure in the Wismut cohort was analyzed using the two-stage clonal expansion (TSCE) model. A total of 2996 lung cancer deaths among the 58,695 male workers were observed during the follow-up period between 1946 and 2003. Adjustment to silica exposure was performed to find a more accurate estimation of the risk of radon exposure. An additional analysis with the descriptive excess relative risk (ERR) model was carried out for comparison. The TSCE model that best describes the data is nonlinear in the clonal expansion with radon exposure and has a saturation level at an exposure rate of [Formula: see text]. The excess relative risk decreases with age and shows an inverse exposure rate effect. In comparison with the ERR model, the TSCE model predicts a considerably larger risk for low exposures rates below [Formula: see text]. Comparison to other mechanistic studies of lung cancer after exposure to alpha particles using the TSCE model reveals an extraordinary consistency in the main features of the exposure response, given the diversity in the characteristics of the cohorts and the exposure across different studies. This suggests that a nonlinear response mechanism in the clonal expansion, with some level of saturation at large exposure rates, may be playing a crucial role in the development of lung cancer after alpha particle irradiation. PMID:27334643

  5. Mechanistic study on lung cancer mortality after radon exposure in the Wismut cohort supports important role of clonal expansion in lung carcinogenesis.

    PubMed

    Zaballa, I; Eidemüller, M

    2016-08-01

    Lung cancer mortality after radon exposure in the Wismut cohort was analyzed using the two-stage clonal expansion (TSCE) model. A total of 2996 lung cancer deaths among the 58,695 male workers were observed during the follow-up period between 1946 and 2003. Adjustment to silica exposure was performed to find a more accurate estimation of the risk of radon exposure. An additional analysis with the descriptive excess relative risk (ERR) model was carried out for comparison. The TSCE model that best describes the data is nonlinear in the clonal expansion with radon exposure and has a saturation level at an exposure rate of [Formula: see text]. The excess relative risk decreases with age and shows an inverse exposure rate effect. In comparison with the ERR model, the TSCE model predicts a considerably larger risk for low exposures rates below [Formula: see text]. Comparison to other mechanistic studies of lung cancer after exposure to alpha particles using the TSCE model reveals an extraordinary consistency in the main features of the exposure response, given the diversity in the characteristics of the cohorts and the exposure across different studies. This suggests that a nonlinear response mechanism in the clonal expansion, with some level of saturation at large exposure rates, may be playing a crucial role in the development of lung cancer after alpha particle irradiation.

  6. 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)

  7. 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.

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

    SciTech Connect

    George, A. C.

    2008-08-07

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

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

    NASA Astrophysics Data System (ADS)

    George, A. C.

    2008-08-01

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

  10. Invited article: radon and thoron intercomparison experiments for integrated monitors at NIRS, Japan.

    PubMed

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

    2014-02-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2014-02-01

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

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

    SciTech Connect

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

    2014-02-15

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

  13. State-of-the-art exposure chamber for highly controlled and reproducible THz biological effects studies

    NASA Astrophysics Data System (ADS)

    Cerna, Cesario Z.; Elam, David P.; Echchgadda, Ibtissam; Sloan, Mark A.; Wilmink, Gerald J.

    2014-03-01

    Terahertz (THz) imaging and sensing technologies are increasingly being used at international airports for security screening purposes and at major medical centers for cancer and burn diagnosis. The emergence of new THz applications has directly resulted in an increased interest regarding the biological effects associated with this frequency range. Knowledge of THz biological effects is also desired for the safe use of THz systems, identification of health hazards, and development of empirically-based safety standards. In this study, we developed a state-of-the-art exposure chamber that allowed for highly controlled and reproducible studies of THz biological effects. This innovative system incorporated an industry grade cell incubator system that permitted a highly controlled exposure environment, where temperatures could be maintained at 37 °C +/- 0.1 °C, carbon dioxide (CO2) levels at 5% +/- 0.1%, and relative humidity (RH) levels at 95% +/- 1%. To maximize the THz power transmitted to the cell culture region inside the humid incubator, a secondary custom micro-chamber was fabricated and incorporated into the system. This micro-chamber shields the THz beam from the incubator environment and could be nitrogen-purged to eliminate water absorption effects. Additionally, a microscope that allowed for real-time visualization of the live cells before, during, and after THz exposure was integrated into the exposure system.

  14. The radon problem

    NASA Astrophysics Data System (ADS)

    Crameri, Reto; Burkart, Werner

    The importance of the radon problem is illustrated by the fact that the indoor exposure to radon and radon daughters amounts to about 40% of the total effective dose equivalent to which the population is exposed to both, from natural and man made sources. This exposure may increase even further due to new building technologies optimized for energy conservation. Although radon and its decay products are well known to cause lung cancer at high exposure levels, considerable controversy remains about the magnitude of risk due to low-level exposure. Linear extrapolation from the dose-response values of uranium miners who were heavily exposed to these nuclides would suggest that a relevant fraction (10-40%) of lung cancers in the general population are caused by the inhalation of radon daughters. Moreover, the results of monitoring programs in several countries during the past years have revealed that for a small, but not negligible fraction of the population, the lifetime exposure from indoor radon daughters is comparable to, or even exceeds the occupational radon exposure of moderately exposed underground miners still showing a significant excess lung cancer frequency.

  15. 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.

  16. Exposure chamber for allergen challenge. The development and validation of a new concept.

    PubMed

    Rønborg, S M; Mosbech, H; Johnsen, C R; Poulsen, L K

    1996-02-01

    Exposure chambers have proven to be valuable tools in studying allergic diseases. The chamber provides a controlled environment and maintains conditions for measuring the amount of allergen inducing symptoms in allergic subjects. The aim of the present study was to develop and test an exposure chamber. The chamber was constructed as an airtight tent, made of transparent polyethylene, easy to adapt to the shape of an existing room, easy to clean, and providing exact allergen-dosage control. Airflow to the interior of the tent was controlled by a variable inlet ventilator fitted with a micropore filter and balanced by a variable high-volume air-sampler on the outlet side. Trace material and allergen were administered as aerosols with a nebulizer connected to the inlet pipe. Samples were obtained from interior surfaces and filters at the outlet. Two different methods were used to test the concept. One method used a colored, neutral trace substance (phenol red indicator) measured photometrically on extracts from filters. Secondly, house-dust mite allergen (Dermatophagoides pteronyssinus) was applied, with samples analyzed by an ELISA technique. The results demonstrated the ability of the system to administer and sample allergen with a high degree of reproducibility. A clinical pilot trial proved the capability of the system to initiate symptoms in allergic subjects. PMID:8738512

  17. Calibration system for measuring the radon flux density.

    PubMed

    Onishchenko, A; Zhukovsky, M; Bastrikov, V

    2015-06-01

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

  18. Contribution of radon and radon daughters to respiratory cancer

    SciTech Connect

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

    1986-12-01

    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.

  19. 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

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

    PubMed Central

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

    2013-01-01

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

  1. 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. PMID:21242168

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

    NASA Astrophysics Data System (ADS)

    Gillmore, Gavin

    2015-04-01

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

  3. Radon and lung cancer.

    PubMed

    Sethi, Tarsheen K; El-Ghamry, Moataz N; Kloecker, Goetz H

    2012-03-01

    Lung cancer is the leading cause of cancer-related deaths worldwide. Radon exposure is the second leading cause of lung cancer, following tobacco smoke. Radon is not only an independent risk factor; it also increases the risk of lung cancer in smokers. Numerous cohort, case-control, and experimental studies have established the carcinogenic potential of radon. The possibility of radon having a causative effect on other cancers has been explored but not yet proven. One of the postulated mechanisms of carcinogenesis is DNA damage by alpha particles mediated by the production of reactive oxygen species. The latter are also thought to constitute one of the common mechanisms underlying the synergistic effect of radon and tobacco smoke. With an estimated 21,000 lung cancer deaths attributable to radon in the United States annually, the need for radon mitigation is well acknowledged. The Environmental Protection Agency (EPA) has established an indoor limit of 4 picocuries (pCi)/L, and various methods are available for indoor radon reduction when testing shows higher levels. Radon mitigation should accompany smoking cessation measures in lung cancer prevention efforts.

  4. 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.

  5. 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. PMID:21498864

  6. Joint analysis of three European nested case-control studies of lung cancer among radon exposed miners: exposure restricted to below 300 WLM.

    PubMed

    Hunter, Nezahat; Muirhead, Colin R; Tomasek, Ladislav; Kreuzer, Michaela; Laurier, Dominique; Leuraud, Klervi; Schnelzer, Maria; Grosche, Bernd; Placek, Vit; Heribanova, Alena; Timarche, Margot

    2013-03-01

    Analyses of lung cancer risk were carried out using restrictions to nested case-control data on uranium miners in the Czech Republic, France, and Germany. With the data restricted to cumulative exposures below 300 working-level-months (WLM) and adjustment for smoking status, the excess relative risk (ERR) per WLM was 0.0174 (95% CI: 0.009-0.035), compared to the estimate of 0.008 (95% CI: 0.004-0.014) using the unrestricted data. Analysis of both the restricted and unrestricted data showed that time since exposure windows had a major effect; the ERR/WLM was six times higher for more recent exposures (5-24 y) than for more distant exposures (25 y or more). Based on a linear model fitted to data on exposures <300 WLM, the ERR WLM of lung cancer at 30 y after exposure was estimated to be 0.021 (95% CI: 0.011-0.040), and the risks decreased by 47% per decade increase in time since exposure. The results from analyzing the joint effects of radon and smoking were consistent with a sub-multiplicative interaction; the ERR WLM was greater for non-smokers compared with current or ex-smokers, although there was no statistically significant variation in the ERR WLM by smoking status. The patterns of risk with radon exposure from the combined European nested case-control miner analysis were generally consistent with those based on the BEIR VI Exposure-Age-Concentration model. Based on conversions from WLM to time weighted averaged radon concentration (expressed per 100 Bq m), the results from this analysis of miner data were in agreement with those from the joint analysis of the European residential radon studies.

  7. Radon: counseling patients about risk.

    PubMed

    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. PMID:2203238

  8. 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.

  9. Radon Research Program, FY 1991

    SciTech Connect

    Not Available

    1992-03-01

    The scientific information being sought in this program encompasses research designed to determine radon availability and transport outdoors, modeling transport into and within buildings, physics and chemistry of radon and radon progeny, dose response relationships, lung cancer risk, and mechanisms of radon carcinogenesis. The main goal of the DOE/OHER Radon Research Program is to develop information to reduce these uncertainties and thereby provide an improved health risk estimate of exposure to radon and its progeny as well as to provide information useful in radon control strategies. Results generated under the Program were highlighted in a National Research Council report on radon dosimetry. The study concluded that the risk of radon exposure is 30% less in homes than in mines. This program summary of book describes the OHER FY-1991 Radon Research Program. It is the fifth in an annual series of program books designed to provide scientific and research information to the public and to other government agencies on the DOE Radon Research Program.

  10. Gene mutation discovery research of non-smoking lung cancer patients due to indoor radon exposure.

    PubMed

    Choi, Jung Ran; Park, Seong Yong; Noh, O Kyu; Koh, Young Wha; Kang, Dae Ryong

    2016-01-01

    Although the incidence and mortality for most cancers such as lung and colon are decreasing in several countries, they are increasing in several developed countries because of an unhealthy western lifestyles including smoking, physical inactivity and consumption of calorie-dense food. The incidences for lung and colon cancers in a few of these countries have already exceeded those in the United States and other western countries. Among them, lung cancer is the main cause of cancer death in worldwide. The cumulative survival rate at five years differs between 13 and 21 % in several countries. Although the most important risk factors are smoking for lung cancer, however, the increased incidence of lung cancer in never smokers(LCINS) is necessary to improve knowledge concerning other risk factors. Environmental factors and genetic susceptibility are also thought to contribute to lung cancer risk. Patients with lung adenocarcinoma who have never smoking frequently contain mutation within tyrosine kinase domain of the epidermal growth factor receptor(EGFR) gene. Also, K-ras mutations are more common in individuals with a history of smoking use and are related with resistance to EFGR-tyrosine kinase inhibitors. Recently, radon(Rn), natural and noble gas, has been recognized as second common reason of lung cancer. In this review, we aim to know whether residential radon is associated with an increased risk for developing lung cancer and regulated by several genetic polymorphisms.

  11. Gene mutation discovery research of non-smoking lung cancer patients due to indoor radon exposure.

    PubMed

    Choi, Jung Ran; Park, Seong Yong; Noh, O Kyu; Koh, Young Wha; Kang, Dae Ryong

    2016-01-01

    Although the incidence and mortality for most cancers such as lung and colon are decreasing in several countries, they are increasing in several developed countries because of an unhealthy western lifestyles including smoking, physical inactivity and consumption of calorie-dense food. The incidences for lung and colon cancers in a few of these countries have already exceeded those in the United States and other western countries. Among them, lung cancer is the main cause of cancer death in worldwide. The cumulative survival rate at five years differs between 13 and 21 % in several countries. Although the most important risk factors are smoking for lung cancer, however, the increased incidence of lung cancer in never smokers(LCINS) is necessary to improve knowledge concerning other risk factors. Environmental factors and genetic susceptibility are also thought to contribute to lung cancer risk. Patients with lung adenocarcinoma who have never smoking frequently contain mutation within tyrosine kinase domain of the epidermal growth factor receptor(EGFR) gene. Also, K-ras mutations are more common in individuals with a history of smoking use and are related with resistance to EFGR-tyrosine kinase inhibitors. Recently, radon(Rn), natural and noble gas, has been recognized as second common reason of lung cancer. In this review, we aim to know whether residential radon is associated with an increased risk for developing lung cancer and regulated by several genetic polymorphisms. PMID:26985396

  12. Plant exposure laboratory and chambers. Volume 2. Appendices 1 through 6

    SciTech Connect

    McDowell, M.

    1986-01-01

    The paper describes the laboratory and support system, the exposure chambers, the computer system, and the hydroponic nursery built to accomplish research on uptake, translocation, and metabolism of toxic organic chemicals by plants. Understanding these processes and the physiological driving mechanisms is essential to predict food-chain contamination and environmental damage from various agricultural and industrial pollutants. Since the chemicals of interest are toxic and studies generally include /sup 14/C as a label for monitoring chemical kinetics, containment was an important criterion. Containment and safety considerations are included.

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

    PubMed

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

    2015-01-01

    We found a way to optimize the image quality and reduce the exposure dose of patients through the proper activity combination of the automatic exposure control system chamber for the dose optimization when examining the pelvic anteroposterior side using the phantom of the human body standard model. We set 7 combinations of the chamber of automatic exposure control system. The effective dose was yielded by measuring five times for each according to the activity combination of the chamber for the dose measurement. Five radiologists with more than five years of experience evaluated the image through picture archiving and communication system using double blind test while classifying the 6 anatomical sites into 3-point level (improper, proper, perfect). When only one central chamber was activated, the effective dose was found to be the highest level, 0.287 mSv; and lowest when only the top left chamber was used, 0.165 mSv. After the subjective evaluation by five panel members on the pelvic image was completed, there was no statistically meaningful difference between the 7 chamber combinations, and all had good image quality. When testing the pelvic anteroposterior side with digital radiography, we were able to reduce the exposure dose of patients using the combination of the top right side of or the top two of the chamber. PMID:26410466

  14. An equilibrium-based model for measuring environmental radon using charcoal canisters.

    PubMed

    Lehnert, A L; Kearfott, K J

    2010-08-01

    Radon in indoor air is often measured using canisters of activated charcoal that function by adsorbing radon gas. The use of a diffusion barrier charcoal canister (DBCC) minimizes the effects of environmental humidity and extends the useful exposure time by several days. Many DBCC protocols model charcoal canisters as simple integrating detectors, which introduces errors due to the fact that radon uptake changes over the exposure period. Errors are compensated for by calculating a calibration factor that is nonlinear with respect to exposure time. This study involves the development and testing of an equilibrium-based model and corresponding measurement protocol that treats the charcoal canisters as a system coming into equilibrium with the surrounding radon environment. This model applies to both constant and temporally varying radon concentration situations, which was essential, as efforts are currently underway using a temporally varying radon chamber. It was found that the DBCCs equilibrate following the relationship E = (1 - e) where E is a measure of how close the DBCC is to equilibrium, t is exposure time, and q is the equilibration constant. This equilibration constant was empirically determined to be 0.019 h. The proposed model was tested in a blind test as well as compared with the currently accepted U.S. Environmental Protection Agency (U.S. EPA) model. Comparisons between the two methods showed a slight decrease in measurement error when using the equilibrium-based method as compared to the U.S. EPA method.

  15. 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.

  16. A new whole-body vapor exposure chamber for protection performance research on chemical protective ensembles.

    PubMed

    Duncan, E J Scott; Dickson, Eva F Gudgin

    2003-01-01

    A chemical vapor exposure chamber was designed to permit the study of whole-body vapor exposure of individuals wearing full protective clothing and equipment systems. A methodology also was developed to quantify the vapor protection performance of chemical protective ensembles (CPE) under safe and validated laboratory procedures. The principal research objectives were to (1) provide a methodology to accurately assess the performance of CPE and equipment under different environmental and chemical vapor challenge conditions; (2) quantify the vapor protection on a per body region basis; (3) have a systems level tool to aid in the research and development of more effective CPE for use in chemical biological environments; and (4) have a safe and reliable means of qualifying new CPE on the basis of vapor protection. Although designed for the evaluation of military-style protective equipment, the procedures apply equally to other styles of CPE used by civilian agencies such as firefighters, police, and hazmat units. The chamber and methodology were specifically designed to examine the vapor protection performance of clothing ensembles, including the details of protection variation over the body. A variety of exposure conditions appropriate to indoor and outdoor scenarios are possible, including the effects of wind, temperature, and relative humidity. Protection performance results from a number of individuals wearing typical military-style CPE are presented. These results demonstrate that there is no such thing as a unique protection performance level obtained for a given CPE. Rather, the individual and the ensemble interact differently in each situation, resulting in a protection performance distribution for individuals, and for groups of wearers, even under a standardized set of exposure conditions. PMID:12688845

  17. 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.

  18. 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. PMID:26435745

  19. 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.

  20. 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.

  1. Design and characterization of a two-stage human subject exposure chamber.

    PubMed

    Kuprov, Roman Y; Buck, David; Pope, C Arden; Eatough, Delbert J; Hansen, Jaron C

    2011-08-01

    A human subject exposure chamber, designed to hold six to eight subjects, coupled to an approximately 30-m3 Teflon reaction bag was designed and built to provide exposures that mimic the production and photochemical oxidation of atmospheric pollutants resulting from the combustion of coal or wood from a stove. The combustion products are introduced into the Teflon bag under atmospheric conditions. Photochemical oxidation of this mixture is accomplished by exposure to tropospheric sun-like radiation from an array of ultraviolet and black lamps. The aerosol in the Teflon reaction bag is then transferred into the exposure room to maintain a constant, lower exposure level. Continuous and semicontinuous monitoring of the gas and particulate matter (PM) pollution in the exposure room and the reaction bag is accomplished using a suite of instruments. This suite of instruments allows for the measurement of the concentrations of total and nonvolatile PM, nitric oxide, nitrogen dioxide, carbon monoxide, carbon dioxide, and ozone. The concentration of the particles was monitored by an R&P tapered element oscillating microbalance monitor. The chemical composition of the PM and its morphological characterization is accomplished by collecting samples in filter packs and conducting ion chromatography, elemental X-ray fluorescence, and scanning electron microscopy analyses. The concentration and composition of emissions from combustion of wood and coal is described. The results of this study suggest that although the bulk compositions of particulate emissions from the combustion of coal or wood in a stove have many similarities, the wood smoke aerosol is photochemically reactive, whereas the coal smoke aerosol is not.

  2. Radon Research Program, FY 1992

    SciTech Connect

    Not Available

    1993-04-01

    The United States Department of Energy, Office of Health and Environmental Research (DOE/OHER) is the principal federal agency conducting basic research related to indoor radon. The scientific information being sought in this program encompasses research designed to determine radon availability and transport outdoors, modeling transport into and within buildings, physics and chemistry of radon and radon progeny, dose response relationships, lung cancer risk, and mechanisms of radon carcinogenesis. There still remains a significant number of uncertainties in the currently available knowledge that is used to estimate lung cancer risk from exposure to environmental levels of radon and its progeny. The main goal of the DOE/OHER Radon Research Program is to develop information to reduce these uncertainties and thereby provide an improved health risk estimate of exposure to radon and its progeny and to identify and understand biological mechanisms of lung cancer development and required copollutants at low levels of exposure. Information useful in radon control strategies is also provided by the basic science undertaken in this program.

  3. The Austrian radon activities on the way to the national radon action plan.

    PubMed

    Gruber, V; Ringer, W; Wurm, G; Haider, W

    2014-07-01

    Based on the new Euratom Basic Safety Standards (BSS), all EU member states will be obliged to design a strategy to address long-term risks from radon exposure, which is laid down in the 'national radon action plan'. In Austria, the National Radon Centre is responsible for the development of the action plan. This paper presents the current and planned radon protection activities on the way to establish the radon action plan--like the national radon database, the definition of radon risk areas by improving the existing radon map, as well as strategies and activities to increase the radon awareness of the public and decision-makers and to involve the building sector. The impact of and the need for actions caused by the BSS requirements on the Austrian radon legislation, strategy and programme are discussed.

  4. Measurement systems and indices of miners' exposure to radon daughter products in the air of mines.

    PubMed

    Domański, T

    1990-01-01

    This paper presents the classification of measurement systems that may be used for the assessment of miners' exposure to radiation in mines. The following systems were described and characterized as the Air Sampling System (ASS), the Environmental Control System (ECS), the Individual Dosimetry System (IDS), the Stream Monitoring System (SMS) and the Exhaust Monitoring System (EMS). The indices for evaluation of miners' working environments, or for assessment of individual or collective miners' exposure, were selected and determined. These are: average expected concentration (CAE), average observed concentration (CAO), average expected rate of exposure cumulation rate (EEXP), average observed exposure cumulation rate (EOBS), average effective exposure cumulation rate (EEFF). Mathematical formulae for determining all these indicators, according to the type of measurement system used in particular mines, are presented. The reliability of assessment of miners' exposure in particular measurement systems, as well as the role of the possible reference system, are discussed. PMID:2134320

  5. 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.

  6. 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

  7. H. R. 2837: A Bill to amend the Toxic Substances Control Act to assist States in responding to the threat to human health posed by exposure to radon. Introduced in the House of Representatives, One Hundredth Congress, Second Session, Report No. 100-1047

    SciTech Connect

    Not Available

    1988-01-01

    A bill has been introduced to amend the Toxic Substances Control Act to assist States in responding to the threat to human health posed by exposure to radon. The Toxic Substances Control Act is amended by adding the following new title after title II: Title III-Indoor Radon Abatement. The long-term purpose of this Act is to maintain indoor levels of radon equal to the radon levels of the ambient air outside of buildings.

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

    PubMed

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

    2016-03-01

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

  9. An overview of radon research in Canada.

    PubMed

    Chen, Jing; Whyte, Jeff; Ford, Ken

    2015-11-01

    Based on new scientific information and broad public consultation, the Government of Canada updated the guideline for exposure to indoor radon and launched a multi-year radon programme in 2007. Major achievements in radon research accomplished in the past 7 y are highlighted here.

  10. Recoil-deposited Po-210 in radon dwellings

    SciTech Connect

    Samuelsson, C.

    1990-12-31

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

  11. 2014 ICHLNRRA intercomparison of radon/thoron gas and radon short-lived decay products measuring instruments in the NRPI Prague.

    PubMed

    Jílek, K; Timková, J

    2015-06-01

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

  12. 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.

  13. Alerting patients to the risk of radon

    SciTech Connect

    Bell, R.T.; Stewart, K.M.

    1993-06-01

    The potential lung cancer risk from exposure to radon gas and the development of appropriate public health policy have been the subject of much discussion for several years. The American Lung Association has taken a leading role in educating the public on radon and other environmental hazards. This article presents background on radon, including the issues of risk assessment and policy development; reviews the current understanding of the hazards of exposure and the scope of the problem; describes how to test for radon; and discusses how to decrease radon levels.

  14. 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.

  15. The effect on the radon diffusion coefficient of long-term exposure of waterproof membranes to various degradation agents.

    PubMed

    Navrátilová Rovenská, Katerina

    2014-07-01

    Waterproofing, usually made of bitumen or polymers with various additives, is used to protect buildings mainly against dampness, but also against radon transported from the soil beneath the building. The radon diffusion coefficient is a material property which is considered to be strongly influenced by the inner structure (chemical composition, crystallinity) of a measured sample. We have used this parameter together with measurements of mechanical properties (hardness, tensile strength, elongation at break, etc.) and FTIR spectroscopy has been used in order to describe the changes in material properties induced by long-term degradation. This paper summarizes the results of radon diffusion coefficient measurements of waterproof materials exposed to radon, soil bacteria, high temperature and combinations of these factors. We have discovered changes as high as 83 % have been discovered compared to virgin samples. PMID:24748486

  16. Influence of environmental thoron on radon measurements and related issues

    SciTech Connect

    Tokonami, Shinji; Takahashi, Hiroyuki; Kobayashi, Yosuke; Sorimachi, Atsuyuki; Ishikawa, Tetsuo; Yoshinaga, Shinji; Kovacs, Tibor; Kavasi, Norbert; Sugino, Masato

    2008-08-07

    Recently importance of thoron measurements has also been recognized from the viewpoint of accurate radon measurements. The present study covers specification of the NIRS thoron chamber, passive measurement technique of radon and thoron and thoron interference on radon measurements from both experimental studies and field experiences on epidemiological study area.

  17. 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.

  18. 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.

  19. Radon and radon progeny in the Carlsbad Caverns

    SciTech Connect

    Cheng, Y.S.; Chen, T.R.; Wasiolek, P.T; Van Engen, A.

    1997-01-01

    Measurements were made in July 1994 to determine air exchange rate, aerosol characteristics, radon concentrations, and radon progeny activity size distributions in the Carlsbad Caverns. The measured radon concentrations were stable at a level of 1821{+-}55 Bq m{sup -3}(mean {+-}SD). Using a SF{sub 6} trace gas method, it was determined that stagnant air in the Caverns was exchanged once every 18 days. The stagnant air was a key factor in maintaining stable environmental conditions and radon concentration. The low air exchange and few aerosol sources inside the Caverns also contributed to the low aerosol concentrations of between 200 and 400 cm{sup -3} - orders of magnitude lower than mining, indoor, and outdoor environments. The alpha spectrum showed radon progeny but no thoron progeny. The activity size distribution of radon progeny showed typical bimodal distributions with higher unattached fractions than other natural environments. The high unattached fraction was attributed to the extremely low aerosol concentration. Considering the seasonal variation in radon concentration, the estimated cumulative exposure of 1.65 working level months (WLMs) for a worker spending 2000 h in the Carlsbad Caverns with the observed radon concentration seems high, but it is still below the recommended occupational exposure limit for underground uranium miners. 43 refs., 11 figs., 2 tabs.

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

    PubMed

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

    2013-08-01

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

  1. Comparative Measurements of Radon Concentration in Soil Using Passive and Active Methods in High Level Natural Radiation Area (HLNRA) of Ramsar

    PubMed Central

    Amanat, B; Kardan, M R; Faghihi, R; Hosseini Pooya, S M

    2013-01-01

    Background: Radon and its daughters are amongst the most important sources of natural exposure in the world. Soil is one of the significant sources of radon/thoron due to both radium and thorium so that the emanated thoron from it may cause increased uncertainties in radon measurements. Recently, a diffusion chamber has been designed and optimized for passive discriminative measurements of radon/thoron concentrations in soil. Objective: In order to evaluate the capability of the passive method, some comparative measurements (with active methods) have been performed. Method: The method is based upon measurements by a diffusion chamber, including two Lexan polycarbonate SSNTDs, which can discriminate the emanated radon/thorn from the soil by delay method. The comparative measurements have been done in ten selected points of HLNRA of Ramsar in Iran. The linear regression and correlation between the results of two methods have been studied. Results: The results show that the radon concentrations are within the range of 12.1 to 165 kBq/m3 values. The correlation between the results of active and passive methods was measured by 0.99 value. As well, the thoron concentrations have been measured between 1.9 to 29.5 kBq/m3 values at the points. Conclusion: The sensitivity as well as the strong correlation with active measurements shows that the new low-cost passive method is appropriate for accurate seasonal measurements of radon and thoron concentration in soil. PMID:25505760

  2. 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)

  3. 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. PMID:6885442

  4. Radon and the system of radiological protection.

    PubMed

    Lecomte, J F

    2012-01-01

    At its meeting in Porto, Portugal, in November 2009, the Main Commission of the International Commission on Radiological Protection (ICRP) approved the formation of a new Task Group, reporting to Committee 4, to develop guidance on radiological protection against radon exposure. This article describes the Task Group's draft report entitled "Radiological Protection against Radon Exposure" which has been posted on the ICRP website for public consultation between January and June 2012. In this report, the Commission provides updated guidance on radiological protection against radon exposure. The report was developed considering the recently consolidated ICRP general recommendations, the new scientific knowledge about radon risk, and the experience gained by many organisations and countries in the control of radon exposure. The report describes the characteristics of radon exposure, covering sources and transfer mechanisms, nature of the risk, exposure conditions, similarities with other existing exposure situations, and challenges to manage radon exposure. In order to control radon exposure, the Commission recommends an integrated approach that is focused as much as possible on the management of the building or location in which radon exposure occurs, regardless of the purpose of the building and the category of the occupants. This approach is based on the optimisation principle, and a graded approach according to the degree of responsibilities at stake, notably in workplaces, and the level of ambition of the national authorities. The report emphasises the importance of preventive actions, and provides recommendations on how to control radon exposure in workplaces when workers' exposure can reasonably be regarded as being the responsibility of the operating management. In such a case, workers' exposures are considered to be occupational, and are controlled using the corresponding requirements on the basis of the optimisation principle, and application, as appropriate

  5. Radon and lung cancer: assessing and mitigating the risk.

    PubMed

    Choi, Humberto; Mazzone, Peter

    2014-09-01

    Radon is a naturally occurring radioactive gas. Its progenies emit alpha particles capable of causing tissue damage. Radon exposure is estimated to be the second most common cause of lung cancer in the United States. Management of patients with a history of radon exposure should involve a lung cancer specialist.

  6. 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

  7. Computer controlled chamber measurements for clay adherence relevant for potential dioxin exposure through skin.

    PubMed

    Ferguson, Alesia; Bursac, Zoran; Johnson, Wayne; Davis, Jasmine

    2012-01-01

    A computer-controlled mechanical chamber was used to control the contact between aluminum sheet samples laden with clay, and cotton sheet samples for the measurement of mass transfer. The contact parameters of pressure (20 to 60 kPa) and time (10 to 70 sec) were varied for 160 multiple experiments of mass soil transfer. Before log transformation the average transfer for 'First Transfer' of clay particles was 34.4 ± 6.3 mg/8.97 cm(2) while that for 'Total Transfer' was 36.1 ± 6.8 mg/8.97 cm(2). Second contact, therefore, resulted in an average transfer of 1.70 ± 0.76 mg/8.97 cm(2). These values are well above adherence values measured for potting soil and sand as reported for previous experiments using the same methodologies. Based on the univariate analysis and the multiple regression analysis we were able to see some effect of parameters on the clay adherence values. The effect of pressure increases was significant for the higher levels of 50 and 60 kPa. In addition, we observed that increases in temperature were significant for 'First Transfer,' and less so for 'Total Transfer'. Past experiments using potting soil and play sand show high adherence values to human cadaver skin over cotton sample; the same scenario would be expected for clay. This data set can be used to improve estimates of dermal exposure to dioxins found in ball clays often used by artisans in the making of pottery.

  8. 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)

  9. Effects of Elevated Radon Levels on Kanne Tritium Monitors

    SciTech Connect

    Farrell, W.E.

    2003-11-24

    The Savannah River Site has used Kanne ionization chambers since the late 1950's to monitor for airborne tritium in reactor facilities. Two Kanne monitors indicated elevated airborne tritium levels while monitoring a non-ventilated room used to store tritiated liquid moderator. Subsequent air sample analysis failed to reveal the presence of airborne tritium. It was suspected that elevated radon levels caused the Kanne monitors to falsely indicate tritium activity. Two commercially available monitoring systems were used to quantify radon levels in the storage room. Measurements performed during this evaluation found that radon caused the Kanne monitors in the storage room to falsely indicate the presence of airborne tritium. A side-by-side comparison of a filtered versus an unfiltered Kanne monitor found that a high efficiency particulate filter reduced monitor response to near background under high radon conditions. It was recommended that a high efficiency filter be installed on the dedicated storage room Kanne monitor and that the room be de-posted as an Airborne Radioactivity Area. It was also found that the Kanne monitors would detect a spill from a single drum of moderator within minutes and the dose rate due to tritium exposure at 20 hours following this spill would be 4.56 rem/hour.

  10. 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.

  11. Methodology issues in risk assessment for radon

    SciTech Connect

    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 US from indoor radon exposure. The accuracy of the estimated 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 US 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.

  12. Factors Affecting Radon Concentration in Houses

    NASA Astrophysics Data System (ADS)

    Al-Sharif, Abdel-Latif; Abdelrahman, Y. S.

    2001-03-01

    The dangers to the human health upon exposure to radon and its daughter products is the main motivation behind the vast number of studies performed to find the concentration of radon in our living environment, including our houses. The presence of radon and its daughter products in houses are due to various sources including building materials and the soil under the houses. Many factors affect radon concentration in our houses, the elevation above ground level,ventilation, building materials and room usage being among these factors. In our paper, we discuss the effect of elevation above ground level, room usage and ventilation on the Radon concentration in houses. The faculty residences of the Mu'tah University (Jordan) were chosen in our study. Our results showed that the concentration of radon decreases with elevation. Ventilation rate was also found to affect radon concentration, where low concentrations observed for areas with good ventilation.

  13. International intercomparison of measuring instruments for radon/thoron gas and radon short-lived daughter products in the NRPI Prague.

    PubMed

    Jílek, K; Hýža, M; Kotík, L; Thomas, J; Tomášek, L

    2014-07-01

    During the 7th European Conference on Protection Against Radon at Home and at Work held in the autumn of 2013 in Prague, the second intercomparison of measuring instruments for radon and its short-lived decay products and the first intercomparison of radon/thoron gas discriminative passive detectors in mix field of radon/thoron were organised by and held at the Natural Radiation Division of the National Radiation Protection Institute (NRPI) in Prague. In total, 14 laboratories from 11 different countries took part in the 2013 NRPI intercomparison. They submitted both continuous monitors for the measurement of radon gas and equivalent equilibrium radon concentration in a big NRPI chamber (48 m3) and sets of passive detectors including radon/thoron discriminative for the measurement of radon gas in the big chamber and thoron gas in a small thoron chamber (150 dm3).

  14. Measurement and distribution of radon and radon progeny: An overview of indoor-radon risk reduction in the United States

    SciTech Connect

    Osborne, M.; Harrison, J.

    1992-01-01

    The paper presents an overview of indoor radon risk reduction in the U.S. EPA currently estimates that 15,000-20,000 Americans die each year from radon-induced lung cancer. The estimate is based on epidemiological data which establish the link between radon and lung cancer, and surveys which provide estimates of radon exposure to the American public. EPA and state cosponsored radon surveys conducted in 34 states have indicated that houses with elevated radon levels exist in all parts of the U.S. These surveys have also indicated that radon levels in individual houses cannot be predicted with any degree of accuracy with existing methods. Individual houses must be tested. Based on these surveys, the EPA estimates that up to 8 million houses have annual average radon levels in the living area which exceed EPA's action guideline of 150 Bq/cu m. Responding to the great health risk posed by indoor radon, EPA, through its comprehensive Radon Action Program, has focused on many activities designed to reduce risk to the public from indoor radon. Key activities in the effort include the research and development of risk-reduction technology and the transfer of the technology to state and local governments, private sector industry, and the public.

  15. 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

  16. Radon concentration measurements in bituminous coal mines.

    PubMed

    Fisne, Abdullah; Okten, Gündüz; Celebi, Nilgün

    2005-01-01

    Radon measurements were carried out in Kozlu, Karadon and Uzülmez underground coal mines of Zonguldak bituminous coal basin in Turkey. Passive-time integrating method, which is the most widely used technique for the measurement of radon concentration in air, was applied by using nuclear etched track detectors (CR-39) in the study area. The radon concentration measurements were performed on a total of 42 points in those three mines. The annual exposure, the annual effective dose and lifetime fatality risk, which are the important parameters for the health of workers, were estimated based on chronic occupational exposure to the radon gas, which is calculated using UNCEAR-2000 and ICRP-65 models. The radon concentrations at several coal production faces are higher than the action level of 1000 Bq m(-3). It is suggested that the ventilation rates should be rearranged to reduce the radon concentration.

  17. Review of radon and lung cancer risk

    SciTech Connect

    Samet, J.M.; Hornung, R.W. )

    1990-03-01

    Radon, a long-established cause of lung cancer in uranium and other underground miners, has recently emerged as a potentially important cause of lung cancer in the general population. The evidence for widespread exposure of the population to radon and the well-documented excess of lung cancer among underground miners exposed to radon decay products have raised concern that exposure to radon progeny might also be a cause of lung cancer in the general population. To date, epidemiological data on the lung cancer risk associated with environmental exposure to radon have been limited. Consequently, the lung cancer hazard posed by radon exposure in indoor air has been addressed primarily through risk estimation procedures. The quantitative risks of lung cancer have been estimated using exposure-response relations derived from the epidemiological investigations of uranium and other underground miners. We review five of the more informative studies of miners and recent risk projection models for excess lung cancer associated with radon. The principal models differ substantially in their underlying assumptions and consequently in the resulting risk projections. The resulting diversity illustrates the substantial uncertainty that remains concerning the most appropriate model of the temporal pattern of radon-related lung cancer. Animal experiments, further follow-up of the miner cohorts, and well-designed epidemiological studies of indoor exposure should reduce this uncertainty. 18 references.

  18. Intercomparison of Retrospective Radon Detectors

    SciTech Connect

    Field, R W.; Steck, D J.; Parkhurst, Maryann ); Mahaffey, Judith A. ); Alavanja, M C.

    1998-11-01

    We performed both a laboratory and 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, Pb-210, in glass. The detectors use track registration material in direct contact with glass surfaces to measure the alpha emission of a Pb-210 decay product, Po-210. The detector's track density generation rate (tracks cm{sup -2} hr{sup -1}) 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 Po-210 and hence, the cumulative radon gas exposure. The goals of the intercomparison were to: (1) 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, (2) 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 (3) 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 Po-210 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.

  19. 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

  20. 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

  1. 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

  2. Identification of Surrogate Measures of Diesel Exhaust Exposure in a Controlled Chamber Study

    EPA Science Inventory

    Exposure to diesel exhaust (DE) has been associated with acute cardiopulmonary and vascular responses, chronic noncancer health effects, and respiratory cancers in humans. To better understand DE exposures and eventually their related health effects, we established a controlled c...

  3. 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. PMID:26925235

  4. [The radon risk in Lombardy].

    PubMed

    Facchini, U; Sesana, L; Agostoni, G; Testa, V

    1997-10-01

    We investigated the geographical distribution of lung cancer mortality rates in some Italian regions, Lombardy and Emilia-Romagna in particular, where the investigation was mainly focused on the risk related to the presence of radon inside dwelling-houses. We referred to the death certificates provided by the Central Institute of Statistics (ISTAT) relative to the years 1980-1988 to calculate the relevant mortality rates. Mortality rates appear higher in some northern than in southern regions and in the islands and also (> a factor of 10) in the male than in the female population; the mortality rates in the male population exhibit a linear correlation with past cigarette smoking. The death rates in the male population (age range: 35-64 years) in northern Italy average 100 events/100,000 inhabitants, but several local health centers in Lombardy at the foot of the Alpine range, north of the Po River, have mortality rates over 50% higher than estimated rates. We considered radon exposure in Lombardy dwelling-houses. The Alps are rich in granite rocks, with 50-150 Bq/kg uranium concentrations, which produce the sediments, sands and gravels making the ground of the Lombardy plain. A recent survey of indoor radon exposure levels showed average values around 100 Bq/m3. The National Academy of Sciences (Washington, DC) has presented a formula to calculate the relative risk of lung cancer related to radon exposure during a lifetime. When this model was applied to excess events in Lombardy, acceptable agreement was found with the assumption that excess deaths are ascribable to higher radon exposure levels. We also compared Lombardy with Emilia-Romagna where the sediments and soil in the plain come from the Apennine range where calcareous rocks have low uranium content. Radon exposure levels in Emilia-Romagna were around 50 Bq/m3 and the radon risk factor in this region is therefore not particularly significant.

  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. PMID:27474991

  6. 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.

  7. The Effect of Ultrafine Aerosol (0.5 to 50 NM (0.05 Micrometers)) on the Deposition of Radon Progeny in Human Lungs and Implications for the Measurement of Exposure.

    NASA Astrophysics Data System (ADS)

    Schmalbeck, Linda Michaels

    1995-01-01

    Despite a generally acknowledged public health risk from indoor exposure to airborne radon progeny, measurement techniques in current use do not provide sufficient information to assess risk from exposures in the home. By contrast, a simple, direct, measurement (the working level month) is a reliable starting point for the evaluation of miners' risks from radon progeny exposure. Ultrafine particles (0.5 to 50 nm in diameter) are frequently present in room air, especially during high occupancy times when activities like cooking and cleaning are taking place; but they are virtually absent from mine air. Measurement techniques used to evaluate mine and indoor air exposures do not supply any size-based data. Few studies of ultrafine aerosol deposition in humans have been undertaken, and none of these has specifically examined ultrafine particle deposition in the radiosensitive bronchial region of the respiratory tract. In this research, the effect of ultrafine aerosol on radon progeny deposition in the bronchial airways was studied using: (1) a unique human exposure data base involving 8 men and 4 women volunteers, (2) a mathematical model describing the attachment behavior of radon progeny in the presence of aerosol developed as part of this work, and (3) a human respiratory-tract deposition model. The addition of ultrafine aerosol to the air breathed by human subjects more than doubled the amount of radon progeny activity deposited in the bronchial region of the subjects' lungs, although radon gas concentration was held constant during all exposure experiments. The gamma activity measured in vivo remained higher at all times after exposure to ultrafine aerosol, while the rate of gamma activity clearance from the region was, on average, about 40 percent faster following ultrafine aerosol exposure. The human exposure data demonstrated that some aerosol size information is crucial to the determination of regional lung deposition and, consequently, the calculation of

  8. Development of a dose-controlled multiculture cell exposure chamber for efficient delivery of airborne and engineered nanoparticles

    NASA Astrophysics Data System (ADS)

    Asimakopoulou, Akrivi; Daskalos, Emmanouil; Lewinski, Nastassja; Riediker, Michael; Papaioannou, Eleni; Konstandopoulos, Athanasios G.

    2013-04-01

    In order to study the various health influencing parameters related to engineered nanoparticles as well as to soot emitted by Diesel engines, there is an urgent need for appropriate sampling devices and methods for cell exposure studies that simulate the respiratory system and facilitate associated biological and toxicological tests. The objective of the present work was the further advancement of a Multiculture Exposure Chamber (MEC) into a dose-controlled system for efficient delivery of nanoparticles to cells. It was validated with various types of nanoparticles (Diesel engine soot aggregates, engineered nanoparticles for various applications) and with state-of-the-art nanoparticle measurement instrumentation to assess the local deposition of nanoparticles on the cell cultures. The dose of nanoparticles to which cell cultures are being exposed was evaluated in the normal operation of the in vitro cell culture exposure chamber based on measurements of the size specific nanoparticle collection efficiency of a cell free device. The average efficiency in delivering nanoparticles in the MEC was approximately 82%. The nanoparticle deposition was demonstrated by Transmission Electron Microscopy (TEM). Analysis and design of the MEC employs Computational Fluid Dynamics (CFD) and true to geometry representations of nanoparticles with the aim to assess the uniformity of nanoparticle deposition among the culture wells. Final testing of the dose-controlled cell exposure system was performed by exposing A549 lung cell cultures to fluorescently labeled nanoparticles. Delivery of aerosolized nanoparticles was demonstrated by visualization of the nanoparticle fluorescence in the cell cultures following exposure. Also monitored was the potential of the aerosolized nanoparticles to generate reactive oxygen species (ROS) (e.g. free radicals and peroxides generation), thus expressing the oxidative stress of the cells which can cause extensive cellular damage or damage on DNA.

  9. Radon survey in Greece--risk assesment.

    PubMed

    Nikolopoulos, Dimitrios; Louizi, Anna; Koukouliou, Virginia; Serefoglou, Athina; Georgiou, Evangelos; Ntalles, Konstantinos; Proukakis, Charalambos

    2002-01-01

    A large scale radon survey using track etch detectors has been carried out from 1995 to 1998 in Greece in order to estimate the radon concentrations in Greek dwellings and the exposure of the Greek population to radon. The total data set consisted of 1,277 samples. Residential potential alpha energy concentration values ranged between (0.024 +/- 0.009) and (8 +/- 1) WLM per year (P < 0.05) and effective doses between (0.09 +/- 0.04) and (28 +/- 4) mSv (P < 0.05). The mean lifetime risk for the Greek population due to radon was found to be 0.4%.

  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. Concentration en radon dans une maison du Calvados

    NASA Astrophysics Data System (ADS)

    Leleyter, Lydia; Riffault, Benoit; Mazenc, Bernard

    2010-03-01

    Recent studies indicate a link between the risk of lung cancer and residential radon exposure. However, in France, awareness of this problem was made relatively late. Accordingly this study examines the radon concentration in a private home in Calvados. Findings show that the presence of a fireplace in a house can accelerate radon convective transfer, and that simple adjustments to interior and exterior accommodation can significantly reduce radon concentrations in the home.

  12. Testing of various membranes for use in a novel sediment porewater isolation chamber for infaunal invertebrate exposure to PCBs.

    PubMed

    Coleman, Jessica G; Lotufo, Guilherme R; Kennedy, Alan J; Poda, Aimee R; Rushing, Todd S; Ruiz, Carlos E; Bridges, Todd S

    2014-07-01

    In benthic sediment bioassays, determining the relative contribution to exposure by contaminants in overlying water, porewater, and sediment particles is technically challenging. The purpose of the present study was to assess the potential for membranes to be utilized as a mechanism to allow freely dissolved hydrophobic organic contaminants into a pathway isolation exposure chamber (PIC) while excluding all sediment particles and dissolved organic carbon (DOC). This investigation was conducted in support of a larger effort to assess contaminant exposure pathways to benthos. While multiple passive samplers exist for estimating concentrations of contaminants in porewater such as those using solid-phase micro extraction (SPME) and polyoxymethylene (POM), techniques to effectively isolate whole organism exposure to porewater within a sediment system are not available. We tested the use of four membranes of different pore sizes (0.1-1.2μm) including nylon, polycarbonate, polyethylsulfone, and polytetrafluoroethylene with a hydrophilic coating. Exposures included both diffusion of radiolabeled and non-labeled contaminants across membranes from aqueous, sediment slurry, and whole sediment sources to assess and evaluate the best candidate membrane. Data generated from the present study was utilized to select the most suitable membrane for use in the larger bioavailability project which sought to assess the relevance of functional ecology in bioavailability of contaminated sediments at remediation sites. The polytetrafluoroethylene membrane was selected for use in the PIC, although exclusion of dissolved organic carbon was not achieved.

  13. 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.

  14. 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.

  15. The radon monitoring system in Daya Bay Reactor Neutrino Experiment

    NASA Astrophysics Data System (ADS)

    Chu, M. C.; Kwan, K. K.; Kwok, M. W.; Kwok, T.; Leung, J. K. C.; Leung, K. Y.; Lin, Y. C.; Luk, K. B.; Pun, C. S. J.

    2016-02-01

    We developed a highly sensitive, reliable and portable automatic system (H3) to monitor the radon concentration of the underground experimental halls of the Daya Bay Reactor Neutrino Experiment. H3 is able to measure radon concentration with a statistical error less than 10% in a 1-h measurement of dehumidified air (R.H. 5% at 25 °C) with radon concentration as low as 50 Bq/m3. This is achieved by using a large radon progeny collection chamber, semiconductor α-particle detector with high energy resolution, improved electronics and software. The integrated radon monitoring system is highly customizable to operate in different run modes at scheduled times and can be controlled remotely to sample radon in ambient air or in water from the water pools where the antineutrino detectors are being housed. The radon monitoring system has been running in the three experimental halls of the Daya Bay Reactor Neutrino Experiment since November 2013.

  16. A passive radon dosemeter suitable for workplaces.

    PubMed

    Orlando, C; Orland, P; Patrizii, L; Tommasino, L; Tonnarini, S; Trevisi, R; Viola, P

    2002-01-01

    The results obtained in different international intercomparisons on passive radon monitors have been analysed with the aim of identifying a suitable radon monitoring device for workplaces. From this analysis, the passive radon device, first developed for personal dosimetry in mines by the National Radiation Protection Board, UK (NRPB), has shown the most suitable set of characteristics. This radon monitor consists of a diffusion chamber, made of conductive plastic with less than 2 cm height, containing a CR-39 film (Columbia Resin 1939), as track detector. Radon detectors in workplaces may be exposed only during the working hours, thus requiring the storage of the detectors in low-radon zones when not exposed. This paper describes how this problem can be solved. Since track detectors are also efficient neutron dosemeters, care should be taken when radon monitors are used in workplaces, where they may he exposed to neutrons, such as on high altitude mountains, in the surroundings of high energy X ray facilities (where neutrons are produced by (gamma, n) reactions) or around high energy particle accelerators. To this end, the response of these passive radon monitors to high energy neutron fields has been investigated. PMID:12408493

  17. 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

  18. 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.

  19. 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.

  20. 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

  1. (Mutagenicity of radon and radon daughters)

    SciTech Connect

    Not Available

    1990-01-01

    The current 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 will be 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 will be investigated by comparing the response of L5178Y strains which differ in their ability to rejoin X radiation-induced DNA double-strand breaks. This report discusses progress incurred from 4/1/1988--10/1/1990. 5 refs., 9 figs., 6 tabs.

  2. Carcinogenic and cocarcinogenic effects of radon and radon daughters in rats

    SciTech Connect

    Monchaux, G.; Morlier, J.P.; Morin, M.; Lafuma, J.; Masse, R. ); Chameaud, J. )

    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 300 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 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. 62 refs., 6 figs., 9 tabs.

  3. 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....

  4. 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. PMID:15103065

  5. Radon, smoking, and lung cancer: the need to refocus radon control policy.

    PubMed

    Lantz, Paula M; Mendez, David; Philbert, Martin A

    2013-03-01

    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.

  6. Compilation of geogenic radon potential map of Pest County, Hungary

    NASA Astrophysics Data System (ADS)

    Szabó, K. Zs.; Pásztor, L.; Horváth, Á.; Bakacsi, Zs.; Szabó, J.; Szabó, Cs.

    2010-05-01

    222Rn and its effect on the human health have recently received major importance in environmental studies. This natural radioactive gas accounts for about 9% of lung cancer death and about 2% of all deaths from cancer in Europe due to indoor radon concentrations. It moves into the buildings from the natural decay chain of uranium in soils, rocks and building materials. Radon mapping regionalizes the average hazard from radon in a selected area as a radon risk map. Two major methods (concerning the applied radon data) have been used for mapping. One uses indoor radon data whereas the other is based on soil gas radon data. The outputs of the second approach are the geogenic radon potential maps. The principal objective of our work is to take the first step in geogenic radon mapping in Hungary. Soil samples collected in Pest County (Central Region of Hungary) in the frame of a countrywide soil survey (Soil Information and Monitoring System) were studied to have empirical information of the potential radon risk. As the first two steps radium concentration of soil samples, collected at 43 locations sampling soil profiles by genetic horizons from the surface level down to 60-150 cm, were determined using HPGe gamma-spectroscopy technique, as well as measurement of radon exhalation on the soil samples were carried out applying closed radon accumulation chamber coupled with RAD7 radon monitor detector. From these data the exhalation coefficient was calculated, which shows how many percent of the produced radon can come out from the sample. This rate strongly depends on the depth: at circa 100 cm a drastic decrease have been noticed, which is explained by the change in soil texture. The major source of indoor radon is the soil gas radon concentration (Barnet et al., 2005). We estimated this value from the measured radon exhalation and calculated soil porosity and density. The soil gas radon concentration values were categorized after Kemski et al. (2001) and then the

  7. Indoor radon and lung cancer. Estimating the risks

    SciTech Connect

    Samet, J.M. )

    1992-01-01

    Radon is ubiquitous in indoor environments. Epidemiologic studies of underground miners with exposure to radon and experimental evidence have established that radon causes lung cancer. The finding that this naturally occurring carcinogen is present in the air of homes and other buildings has raised concern about the lung cancer risk to the general population from radon. I review current approaches for assessing the risk of indoor radon, emphasizing the extrapolation of the risks for miners to the general population. Although uncertainties are inherent in this risk assessment, the present evidence warrants identifying homes that have unacceptably high concentrations.23 references.

  8. Indoor radon and lung cancer. Estimating the risks.

    PubMed Central

    Samet, J. M.

    1992-01-01

    Radon is ubiquitous in indoor environments. Epidemiologic studies of underground miners with exposure to radon and experimental evidence have established that radon causes lung cancer. The finding that this naturally occurring carcinogen is present in the air of homes and other buildings has raised concern about the lung cancer risk to the general population from radon. I review current approaches for assessing the risk of indoor radon, emphasizing the extrapolation of the risks for miners to the general population. Although uncertainties are inherent in this risk assessment, the present evidence warrants identifying homes that have unacceptably high concentrations. PMID:1734594

  9. Establishment of Airborne Nanoparticle Exposure Chamber System to Assess Nano TiO2 Induced Mice Lung Effects

    NASA Astrophysics Data System (ADS)

    Chen, Chia-Hua; Li, Jui-Ping; Huang, Nai-Chun; Yang, Chung-Shi; Chen, Jen-Kun

    2011-12-01

    A great many governments have schemed their top priority to support the research and development of emerging nanotechnology, which lead to increasing products containing nanomaterials. However, platforms and protocols to evaluate the safety of nanomaterials are not yet established. We therefore design and fabricate a nanoparticle exposure chamber system (NECS) and try to standardize protocols to assess potential health risk of inhalable nanoparticles. This platform comprises: (1) nano-aerosol generators to produce homogeneous airborne nanoparticles, (2) double isolated container to prevent from unexpected exposure to humans, (3) gas supply system for housing animals or incubating cultured cells, and (4) system for automatic control and airborne nanoparticle analysis. The NECS providing multiple functions includes: (1) a secure environment to handle nanomaterials, (2) real-time measurement for the size and distribution of airborne nanoparticles, (3) SOP of safety evaluation for nanomaterials, and (4) key technology for the development of inhalable pharmaceuticals. We used NECS to mimic occupational environment for exploring potential adverse effects of TiO2 nanoparticles. The adult male ICR mice were exposed to 25nm, well-characterized TiO2 particles for 1 and 4 weeks. More than 90% of the inhaled TiO2 nanoparticles deposit in lung tissue, which tends to be captured by alveolar macrophages. Pulmonary function test does not show significant physiological changes between one and 4 weeks exposure. For plasma biochemistry analysis, there are no obvious inflammation responses after exposure for one and 4 weeks; however, disruption of alveolar septa and increased thickness of alveolar epithelial cells were observed. According to our results, the NECS together with our protocols show comprehensive integration and ideally fit the standard of OECD guildelines-TG403, TG412, TG413; it can be further customized to fulfill diverse demands of industry, government, and third party

  10. 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

  11. Indoor radon and lung cancer: Reality or Myth? Part 1

    SciTech Connect

    Cross, F.T.

    1992-12-31

    The Twenty-Ninth Hanford Symposium on Health and the Environment, was held in Richland, Washington, on October 15--19, 1990. At the time of the Symposium, significant results were beginning to emerge from the recently initiated, multidisciplinary Department of Energy (DOE) Radon Program and from the Commission of European Communities (CEC) radon-related studies. Therefore, it was the intent of the organizers to broaden the base of topics on the radon issue that would be discussed at the symposium while, at the same time, emphasizing the health-effect studies. Sessions of the symposium included: radon and progeny exposure assessment; dosimetry modeling; radon transport in soils and into structures; radon and radon progeny sources; methods to control radon and radon progeny exposure; molecular/cellular-level studies; animal studies and exposure systems; biological and statistical modeling studies; epidemiologic studies; public strategy, information, and risk communication; and scientific activities and programs to understand and control exposure to radon (panel). Individual abstracts have been processed separately for the database.

  12. 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.

  13. Study of Natural Radioactivity, Radon Exhalation Rate and Radiation Doses in Coal and Flyash Samples from Thermal Power Plants, India

    NASA Astrophysics Data System (ADS)

    Singh, Lalit Mohan; Kumar, Mukesh; Sahoo, B. K.; Sapra, B. K.; Kumar, Rajesh

    Coal is one of the most important source used for electrical power generation. Its combustion part known as fly ash is used in the manufacturing of bricks, sheets, cement, land filling etc. Coal and its by-products have significant amounts of radionuclide's including uranium, thorium which is the ultimate source of the radioactive gas radon and thoron respectively. Radiation hazard from airborne emissions of coal-fired power plants have been cited as possible causes of health in environmental. Assessment of the radiation exposure from coal burning is critically dependent on the concentration of radioactive elements in coal and in the fly ash. In the present study, samples of coal and flyash were collected from Rajghat Power Plant and Badarpur Thermal Power Plant, New Delhi, India. Radon exhalation is important parameter for the estimation of radiation risk from various materials. Solis State Nuclear Track Detector based sealed Can Technique (using LR-115 type II) has been used for measurement radon exhalation rate. Also accumulation chamber based Continuous Radon Monitor and Continuous Thoron Monitor have been used for radon masss exhalation and thoron surface exhalation rate respectively. Natural radioactivity has been measured using a low level NaI(Tl) detector based on gamma ray spectrometry.

  14. Exposure chambers for studying the partitioning of atmospheric PAHs in environmental compartments: validation and calibration using experimental and computational approaches.

    PubMed

    Desalme, Dorine; Roy, Jean-Claude; Binet, Philippe; Chiapusio, Geneviève; Gilbert, Daniel; Toussaint, Marie-Laure; Girardot, Laurent; Bernard, Nadine

    2013-08-01

    The environmental partitioning of atmospheric polycyclic aromatic hydrocarbons (PAHs) conditions their entry into food chains and subsequent risks for human health. The need for new experimental exposure devices for elucidating the mechanisms governing ecosystemic PAH transfer motivated the elaboration of an original small-scale exposure chamber (EC). A dual approach pairing experimentation and computational fluid dynamics (CFD) was selected to provide comprehensive validation of this EC as a tool to study the transfer and biological effects of atmospheric PAH pollution in microsystems. Soil samples and passive air samplers (PASs) were exposed to atmospheric pollution by phenanthrene (PHE), a gaseous PAH, for 2 weeks in examples of the EC being tested, set up under different conditions. Dynamic concentrations of atmospheric PHE and its uptake by PASs were simulated with CFD, results showing homogeneous distribution and constant atmospheric PHE concentrations inside the ECs. This work provides insight into the setting of given concentrations and pollution levels when using such ECs. The combination of experimentation and CFD is a successful ECs calibration method that should be developed with other semivolatile organic pollutants, including those that tend to partition in the aerosol phase.

  15. 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.

  16. Activity measurements of radon from construction materials.

    PubMed

    Fior, L; Nicolosi Corrêa, J; Paschuk, S A; Denyak, V V; Schelin, H R; Soreanu Pecequilo, B R; Kappke, J

    2012-07-01

    This work presents the results of radon concentration measurements of construction materials used in the Brazilian industry, such as clay (red) bricks and concrete blocks. The measurements focused on the detection of indoor radon activity during different construction stages and the analysis of radionuclides present in the construction materials. For this purpose, sealed chambers with internal dimensions of approximately 60×60×60 cm3 were built within a protected and isolated laboratory environment, and stable air humidity and temperature levels were maintained. These chambers were also used for radon emanation reduction tests. The chambers were built in four major stages: (1) assembly of the walls using clay (red) bricks, concrete blocks, and mortar; (2) installation of plaster; (3) finishing of wall surface using lime; and (4) insulation of wall surface and finishing using paint. Radon measurements were performed using polycarbonate etched track detectors. By comparing the three layers applied to the masonry walls, it was concluded that only the last step (wall painting using acrylic varnish) reduced the radon emanation, by a factor of approximately 2. Samples of the construction materials (clay bricks and concrete blocks) were ground, homogenized, and subjected to gamma-ray spectrometry analysis to evaluate the activity concentrations of 226Ra, 232Th and 40K. The values for the index of the activity concentration (I), radium equivalent activity (Raeq), and external hazard index (Hext) showed that these construction materials could be used without restrictions or concern about the equivalent dose limit (1 mSv/year).

  17. 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%.

  18. 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%.

  19. 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.

  20. Measurement of the concentration of radon gas in the Toirano's caves (Liguria).

    PubMed

    Bruzzone, Diego; Bussallino, Massimo; Castello, Gianrico; Maggiolo, Stefano; Rossi, Daniela

    2006-01-01

    The radioactive gas radon, intermediate term of the decay series of uranium and thorium, is the main contamination source of underground places and may be a risk for high concentration and long exposure time. European and Italian law requires radon concentration to be measured in workplaces and, if the "action level" of 500 Bq/m3 is reached, proper actions must be made in order to decrease the dose commitment. Considering natural showcaves or artificial cavities open to public, the exposition of the visitors is frequently small, due to the short residence time, but accompanying people, remaining underground for long time, may be subject to appreciable dose and the radon concentration should therefore be monitored. The high humidity in natural caves may impair the use of some measuring devices. Therefore, different detection methods were compared (ZnS scintillation counters, E-PERM electret ionisation chambers, cellulose nitrate alpha-track dosimeters) to select the best procedure for long-term investigation. The LR-115 (Kodak) alpha-track dosimeters were insensitive to humidity and permitted to monitor a great number of places at the same time. Measurements have been carried out in the speleological and archaeological site of the Toirano's Caves (Savona, Liguria, Italy) and several points were monitored for two years. Radon concentration strongly depends on the site and changes during the year, due to the difference between internal and external temperature. The maximum dose commitment during the visitors tour, considering the average yearly value of radon concentration, was found to be between 1.5 and 4 microSv. It was found that no risk exists for visitors, but the evaluation of the dose absorbed by the guides and their classification according to the radiation protection law requires a complete monitoring of the average yearly concentration of radon and of the total time spent by each worker into the cave. PMID:17172204

  1. Optical detection of radon decay in air

    PubMed Central

    Sand, Johan; Ihantola, Sakari; Peräjärvi, Kari; Toivonen, Harri; Toivonen, Juha

    2016-01-01

    An optical radon detection method is presented. Radon decay is directly measured by observing the secondary radiolumines cence light that alpha particles excite in air, and the selectivity of coincident photon detection is further enhanced with online pulse-shape analysis. The sensitivity of a demonstration device was 6.5 cps/Bq/l and the minimum detectable concentration was 12 Bq/m3 with a 1 h integration time. The presented technique paves the way for optical approaches in rapid radon detec tion, and it can be applied beyond radon to the analysis of any alpha-active sample which can be placed in the measurement chamber. PMID:26867800

  2. Optical detection of radon decay in air.

    PubMed

    Sand, Johan; Ihantola, Sakari; Peräjärvi, Kari; Toivonen, Harri; Toivonen, Juha

    2016-02-12

    An optical radon detection method is presented. Radon decay is directly measured by observing the secondary radiolumines cence light that alpha particles excite in air, and the selectivity of coincident photon detection is further enhanced with online pulse-shape analysis. The sensitivity of a demonstration device was 6.5 cps/Bq/l and the minimum detectable concentration was 12 Bq/m(3) with a 1 h integration time. The presented technique paves the way for optical approaches in rapid radon detec tion, and it can be applied beyond radon to the analysis of any alpha-active sample which can be placed in the measurement chamber.

  3. 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.

  4. Measurements of radon, thoron, isotopic uranium and thorium to determine occupational and environmental exposure and risk at Fernald Feed Materials Production Center. 1998 annual progress report

    SciTech Connect

    Harley, N.H.

    1998-06-01

    'The research objectives of this report are: (1) To develop an accurate personal radon/thoron monitor to quantitate exposure during remediation. This personal monitor is a miniaturization and modification of the area {sup 222}Rn monitor that has proven accuracy and precision. (2) To develop a personal aerosol particle size sampler, based on the principles of the novel sampler the author has developed. The sampler measures not only {sup 222}Rn decay product aerosol size but long lived nuclides. There are, as yet, no size distribution data on the aerosol particle size distribution of these nuclides during remediation, yet the aerosol particle size is the major determinant of lung dose. (3) To develop the sequential radiochemistry necessary to measure any environmental sample for {sup 228,230,232}Th, {sup 226,228}Ra, {sup 234,235,238}U and {sup 210}Pb. To utilize the radiochemistry to accurately trace and delineate these nuclides in the environment. To obtain historic and present radiochemical data to understand the need for supplemental soil/water etc. measurements.'

  5. 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. PMID:26547560

  6. 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. PMID:26867298

  7. 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.

  8. 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.

  9. A Radon Progeny Deposition Model

    NASA Astrophysics Data System (ADS)

    Guiseppe, V. E.; Elliott, S. R.; Hime, A.; Rielage, K.; Westerdale, S.

    2011-04-01

    The next generation low-background detectors operating underground aim for unprecedented low levels of radioactive backgrounds. Although the radioactive decays of airborne radon (particularly 222Rn) 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 210Pb 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.

  10. 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.

  11. A Study of the Permeation of Radon Through Geomembranes.

    NASA Astrophysics Data System (ADS)

    Mao, Xiaotian

    1990-01-01

    Geomembranes are thin sheets of polymeric materials which have been widely used as linings and covers of containers for liquid or solid waste. In this research various types and thicknesses of geomembranes were evaluated in order to determine which geomembranes could be used as suitable barriers for radon. The permeation of radioactive gases through geomembranes cannot be measured using the method described by the American Society for Testing and Materials (ASTM). The ASTM method estimates the permeation of a single pure gas through a polymeric membrane. The radioactivity of radon would be very high if this method was used. The method developed in this study utilized radon permeation scintillation cell which consisted of a source chamber, a measuring chamber, a radium source, and a geomembrane specimen. The concentration of radon within the source chamber and the measuring chamber was quantified by counting the alpha particles emitted by the decay of radon and its daughters. Based on the percentage of radon permeation through the membranes (defined as the reduction factor), the permeance was calculated. The data indicated that 0.8-mm thick geomembranes such as chlorinated polyethylene, polyurethane and ethylene interpolymer alloy provided a permeance that was less than 500 fmol m^{-2}s ^{-1} Pa^{ -1}. These geomembranes are suitable barriers for radon. The permeance of 0.15-mm polyethylene sheet, which has been used as a radon barrier, is 1.47 times 104 fmol m^{-2}s^ {-1} Pa^{-1} . The effect of certain parameters on radon permeation was quantitatively studied. Such parameters included the difference in air pressure between the two sides of a geomembrane, the thickness of the geomembrane, and the temperature. It was found that a difference of 5 cm Hg in air pressure between the two sides of a geomembrane did not significantly influence the radon permeation. Radon permeation decreased exponentially with increasing thickness of the geomembranes. Radon permeation

  12. Development and use of a branch exposure chamber to determine the effects of ozone on Pinus ponderosa: Objectives and experimental design

    SciTech Connect

    Houpis, J.L.J.; Surano, K.A.; Cowles, S.

    1988-01-01

    This research will develop a branch exposure chamber (BEC) to determine if the amount of carbon a branch receives from neighboring branches is altered by the presence of a BEC, or is altered by the imposition or exclusion of O/sub 3/, and to examine if the response of mature branches is different.

  13. Management of radon: a review of ICRP recommendations.

    PubMed

    Vaillant, Ludovic; Bataille, Céline

    2012-09-01

    This article proposes a review of past and current ICRP publications dealing with the management of radon exposures. Its main objective is to identify and discuss the driving factors that have been used by the Commission during the last 50 years so as to better appreciate current issues regarding radon exposure management. The analysis shows that major evolutions took place in very recent years. As far as the management of radon exposures is concerned, ICRP recommended, until ICRP Publication 103 (ICRP 2007 ICRP Publication 103; Ann. ICRP 37), to use action levels and to consider only exposures above these levels. The Commission has reviewed its approach and now proposes to manage any radon exposure through the application of the optimisation principle and associated reference levels. As far as the assessment of the radon risk is concerned, it appears that the successive changes made by ICRP did not have a strong impact on the values of radon gas concentration recommended as action levels either in dwellings or in workplaces. The major change occurred in late 2009 with the publication of the ICRP Statement on Radon, which acknowledged that the radon risk has been underestimated by a factor of 2, thus inducing a major revision of radon reference levels. PMID:22809956

  14. 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

  15. Canadian population risk of radon induced lung cancer: a re-assessment based on the recent cross-Canada radon survey.

    PubMed

    Chen, J; Moir, D; Whyte, J

    2012-11-01

    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.

  16. A comparison of radon and its decay products' behaviour in indoor air.

    PubMed

    Trevisi, R; Cardellini, F; Leonardi, F; Vargas Trassierra, C; Franci, D

    2014-11-01

    The inhalation of short-lived radon decay products (RDP) yields the greatest contribution to the natural radiation exposure. This paper deals with a study carried out to improve the knowledge of the behaviour of RDPs, their interaction with particulates and the plateout during the time. The tests confirmed that a high aerosol particle concentration increases the probability that an ion sticks to aerosol and remains long in the air, leading to both an increase of F and a decrease of fp, as reported in the literature. The same experimental protocol applied in a small radon chamber showed a strong reduction of the equilibrium factor (an average of ∼10 %), because in a small environment the plateout phenomenon prevails on the attachment to particulate.

  17. Comparisons between soil radon and indoor radon

    SciTech Connect

    Mose, D.G.; Mushrush, G.W.

    1999-10-01

    Several thousand indoor radon measurements have been obtained for homes in northern Virginia. Compilations of these data according to the geologic units under the homes show that some units have relatively high or relatively low medium indoor radon levels, and that these differences persist through all four seasons. An attempt to determine if soil radon and soil permeability could yield similar results, in terms of relative indoor radon, was not successful. Care should be taken in using such measurements to characterize the potential for radon problems in established communities and in areas of as-yet undeveloped property.

  18. 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

  19. Theoretical aspects of the design of a passive radon dosemeter.

    PubMed

    Wilkinson, P; Saunders, B J

    1985-10-01

    Some mathematical aspects of the development and design of a passive radon dosemeter are considered. In particular, a mathematical model is presented that is concerned with the gaseous diffusion of radon into a confined region bounded by a plastic material of known diffusion coefficient. The relationship between the time-integrated radon concentrations, inside and outside a sealed plastic container are derived. Estimates of the exposure of people to radon can be made using the time integrated radon concentration inside a calibrated container containing a CR-39 etched-track device. As a consequence of the analysis, it is possible to design a passive radon dosemeter that will be accurate, resistant to moisture and whose response will be independent of rapid variations in radon concentration. The possibility of using a container of this type for the measurement of diffusion coefficients is discussed.

  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 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

  2. Thorough investigations on indoor radon in Băiţa radon-prone area (Romania).

    PubMed

    Cucoş Dinu, Alexandra; Cosma, Constantin; Dicu, Tiberius; Begy, Robert; Moldovan, Mircea; Papp, Botond; Niţă, Dan; Burghele, Bety; Sainz, Carlos

    2012-08-01

    A comprehensive radon survey has been carried out in Băiţa radon-prone area, Transylvania, Romania, in 4 localities (Băiţa, Nucet, Fînaţe, and Cîmpani) situated in the vicinity of former Romanian uranium mines. Indoor radon concentrations have been measured in 1128 ground floor rooms and cellars of 303 family houses by using CR-39 diffusion type radon detectors. The annual average of indoor radon concentration for Băiţa area was found to be 241±178 Bq m(-3), which is about two times higher than the average value of 126 Bq m(-3), computed for Romania. About 28% of investigated houses exceed the reference level of radon gas in dwellings of 300 Bq m(-3). The indoor radon measurements on each house have been carried out in several rooms simultaneously with the aim of obtaining a more detailed picture on the exposure to radon in the studied area. An analysis on the variability of radon levels among floors (floor-to-floor variation) and rooms (room-to-room variation) and also the influence of factors like the presence of cellar or the age of the building is presented. The coefficient of variation (CV) within ground floor rooms of the same house (room-to-room variation) ranged between 0.9 and 120.8%, with an arithmetic mean of 46.2%, a large variability among rooms within surveyed dwellings being clearly identified. The mean radon concentration in bedrooms without cellar was higher than in bedrooms above the cellar, the difference being statistically significant (t test, one tail, p<0.001, n=82). For houses built during 1960-1970 an increasing trend for radon levels was observed, but overall there was no significant difference in indoor radon concentrations by age of dwelling (one-way ANOVA test, p>0.05).

  3. 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.

  4. 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.

  5. A novel algorithm for quick and continuous tracing the change of radon concentration in environment

    NASA Astrophysics Data System (ADS)

    Tan, Yanliang; Xiao, Detao

    2011-04-01

    Several measurements of the radon concentration are performed by RAD7 in the University of South China. We find that 30-40 min is needed for RAD7 for tracing the concentration of the standard radon chamber. There are two reasons. The first is that the sufficient time of air cycle is needed for the radon concentration in internal cell of RAD7 equal to that of the environment; and the second is that the sufficient decay time is needed for the 218Po concentration in internal cell of RAD7 equal to that of the radon. We used a zeroth order approximation to describe the evolution of the environment radon concentration, and obtained a novel algorithm for quick and continuous tracing the change of radon concentration. The corrected radon concentration obtained through this method is in good agreement with the reference value. This method can be applied to develop and improve the instruments for tracing the change of radon concentration quickly.

  6. Assessment of lifetime lung cancer risks induced by environmental radon

    SciTech Connect

    Mei, G.T.; Schutz, D.F.

    1987-01-01

    Radon and its progeny in air (/sup 218/Po, /sup 214/Pb, /sup 214/Bi, and /sup 214/Po) may enter the human body by inhalation and cause radiation damage to the respiratory tract to induce lung cancer. Among uranium miners, lung cancer induced by long term exposure to elevated levels of radon progeny is well established. The epidemiological evidence provided by such miners is the principal basis for determining the numerical relationship between environmental levels of radon exposure and lung cancer incidence. A number of lung cancer risk models have been published. All of these models are based on an intensity of radon or radon progeny exposure, referring to an average exposure over time, and on an assumed percentage of occupancy. However, the differences in life-styles among individuals or the seasonal variation in radon levels found in a home, which may influence the level of radon exposure, have not been considered in the published risk models. An assessment of the possible lifetime lung cancer risk from exposure to environmental levels of radon is presented.

  7. Personal radon dosimetry from eyeglass lenses.

    PubMed

    Fleischer, R L; Meyer, N R; Hadley, S A; MacDonald, J; Cavallo, A

    2001-01-01

    Eyeglass lenses are commonly composed of allyl-diglycol carbonate (CR-39), an alpha-particle detecting plastic, thus making such lenses personal radon dosemeters. Samples of such lenses have been obtained, etched to reveal that radon and radon progeny alpha tracks can be seen in abundance, and sensitivities have been calibrated in radon chambers as a primary calibration, and with a uranium-based source of alpha particles as a convenient secondary standard. With one exception natural, environmental (fossil) track densities ranged from less than 3,000 to nearly 70,000 per cm2 for eyeglasses that had been worn for various times from one to nearly five years. Average radon concentrations to which those wearers were exposed are inferred to be in the range 14 to 130 Bq x m(-3) (0.4 to 3.5 pCi x l(-1)). A protocol for consistent, meaningful readout is derived and used. In the exceptional case the fossil track density was 1,780,000 cm(-2) and the inferred (24 h) average radon concentration was 6500 Bq x m(-3) (175 pCi x l(-1)) for a worker at an inactive uranium mine that is used for therapy.

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

    SciTech Connect

    Fabrikant, J.I.

    1982-04-01

    Of the important health effects of ionizing radiation, three important late effects - carcinogenesis, teratogenesis and mutagenesis are of greatest concern. This is because any exposure, even at low levels, carries some risk of such deleterious effects. As the dose of radiation increases above very low levels, the risk of health effects increases. Cancer-induction is the most important late somatic effect of low-dose ionizing radiation. Solid cancers, rather than leukemia, are principal late effects in exposed individuals. Tissues vary greatly in their susceptibility to radiation carcinogenesis. The most frequently occurring radiation-induced cancers in man include, in decreasing order of susceptibility: the female breast, the thyroid gland, the blood-forming tissues, the lung, certain organs of the gastrointestinal tract, and the bones. A number of biological and physical factors affect the cancer risk, such as age, sex, life-style, LET, and RBE. Despite uncertainty about low-level radiation risks, regulatory and advisory bodies must set standards for exposure, and individuals need information to be able to make informed judgments for themselves. From the point of view of the policy maker, the overriding concern is the fact that small doses of radiation can cause people to have more cancers than would otherwise be expected. While concern for all radiation effects exists, our human experience is limited to cancer-induction in exposed populations. This discussion is limited to cancer risk estimation and decision-making in relation to the health effects on populations of exposure to low levels of ionizing radiation. Here, low-level radiation will refer to yearly whole-body doses up to 5 rems or 0.05 Sv, or to cumulative doses up to 50 rems or 0.5 Sv from low-LET radiation and from high-LET radiation. (ERB)

  9. Intercomparison of radon and decay product measurements in an underground mine and EPA radon laboratory: A study organized by the IAEA International Radon Metrology Programme

    SciTech Connect

    Budd, G.; Hopper, R.; Braganza, E.; Ronca-Battista, M.; Steinhaeusler, F.; Stegner, P.

    1998-11-01

    The International Atomic Energy Agency (IAEA) in Vienna and the European Union (EU) in Bruxelles formed the International Radon Metrology Programme. The IRMP is designed to assess and foster the improvement of radon and decay product measurements that are made around the world. Within the framework of the IRMP, the U.S. Environmental Protection Agency Radiation and Indoor Environments National Laboratory (EPA) in Las Vegas, Nevada, organized jointly with the U.S. Bureau of Mines an international intercomparison exercise at a former uranium mine (Twilight Mine, Colorado) and the EPA Radon Laboratory. The main objective of this exercise was to compare radon and radon decay product instruments under both well-controlled as well as widely fluctuating exposure conditions. The laboratory exposures occurred under relatively steady radon and decay product conditions, with a moderate equilibrium ratio, while the conditions in the mine fluctuated greatly and the equilibrium ratio was low. An additional purpose of the exercise was to provide a forum for manufacturers and measurement organizations worldwise to exchange information and plan improvements in their operations and calibration programs. Altogether 19 organizations from seven countries intercomparing 32 different radon and radon decay product instruments participated in this exercise. This paper summarizes the results from the analysis of the experimental data obtained in the Bureau of Mines Twilight Mine in July of 1994, as well as the results from the EPA Radon laboratory in August of 1994.

  10. Alteration in carboxyhemoglobin concentrations during exposure to 9 ppm carbon monoxide for 8 hours at sea level and 2134 m altitude in a hypobaric chamber

    SciTech Connect

    Horvath, S.M.; Bedi, J.F. )

    1989-10-01

    Seventeen non-smoking young men served as subjects to determine the alteration in carboxyhemoglobin (COHb) concentrations during exposure to 0 or 9 ppm carbon monoxide for 8 hours (CO) at sea level or an altitude of 2134 meters (7000 feet) in a hypobaric chamber. Nine subjects rested during the exposure and 8 exercised for 10 minutes of each exposure hour at a mean ventilation of 25 L (BTPS). All subjects performed a maximal aerobic capacity test at the completion of their respective exposures. Carboxyhemoglobin concentrations fell in all subjects during their exposures to 0 ppm CO at sea level or 2134 m. During the 8-h exposures to 9 ppm CO, COHb rose linearly from approximately 0.2 percent to 0.7 percent. No significant differences in uptake were found whether the subjects were resting or intermittently exercising during their 8-h exposures. COHb levels attained were similar at both sea level and 2134 m. Maximal aerobic capacity was reduced approximately 7-10 percent consequent to altitude exposure during 0 ppm CO exposures. These values were not altered following exposure for 8 h to 9 ppm CO in either the resting or exercising subjects.

  11. Residential Radon Appears to Prevent Lung Cancer

    PubMed Central

    Scott, Bobby R.

    2011-01-01

    Residential radon has been found to be associated with lung cancer in epidemiological/ecological studies and the researchers have inappropriately concluded that residential radon causes lung cancer. Their conclusion relates to the linear-no-threshold (LNT) hypothesis-based, risk-assessment paradigm; however, the LNT hypothesis has been invalidated in numerous studies. It is shown in this paper that our hormetic relative risk (HRR) model is consistent with lung cancer data where detailed measurements of radon in each home were carried out. Based on the HRR model, low-level radon radioactive progeny is credited for activated natural protection (ANP) against lung cancer including smoking-related lung cancer. The proportion B(x) (benefit function) of ANP beneficiaries increases as the average radon level x increases to near the Environmental Protection Agency’s action level of 4 picocuries/L (approximately 150 Bq m−3). As the average level of radon increases to somewhat above the action level, ANP beneficiaries progressively decrease to zero (B(x) decreases to 0), facilitating the occurrence of smoking-related lung cancers as well as those related to other less important risk factors. Thus, residential radon does not appear to cause lung cancer but rather to protect, in an exposure-level-dependent manner, from its induction by other agents (e.g., cigarette-smoke-related carcinogens). PMID:22461755

  12. An optimized system for measurement of radon levels in buildings by spectroscopic measurement of radon progeny

    NASA Astrophysics Data System (ADS)

    Fröjdh, A.; Thungström, G.; Fröjdh, C.; Petersson, S.

    2011-12-01

    Radon gas, 222Rn, is a problem in many buildings. The radon gas is not harmful in itself, but the decay chain contains charged elements such as 218Po, and 214Po ions which have a tendency to stick to the lungs when inhaled. Alpha particles from the decay of these ions cause damages to the lungs and increase the risk of lung cancer. The recent reduction in the limits for radon levels in buildings call for new simple and efficient measurement tools [1]. The system has been optimized through modifications of the detector size, changes to the filters and the design of the chamber. These changes increase the electric field in the chamber and the detection efficiency.

  13. Detailed diesel exhaust characteristics including particle surface area and lung deposited dose for better understanding of health effects in human chamber exposure studies

    NASA Astrophysics Data System (ADS)

    Wierzbicka, Aneta; Nilsson, Patrik T.; Rissler, Jenny; Sallsten, Gerd; Xu, Yiyi; Pagels, Joakim H.; Albin, Maria; Österberg, Kai; Strandberg, Bo; Eriksson, Axel; Bohgard, Mats; Bergemalm-Rynell, Kerstin; Gudmundsson, Anders

    2014-04-01

    Several diesel exhaust (DE) characteristics, comprising both particle and gas phase, recognized as important when linking with health effects, are not reported in human chamber exposure studies. In order to understand effects of DE on humans there is a need for better characterization of DE when performing exposure studies. The aim of this study was to determine and quantify detailed DE characteristics during human chamber exposure. Additionally to compare to reported DE properties in conducted human exposures. A wide battery of particle and gas phase measurement techniques have been used to provide detailed DE characteristics including the DE particles (DEP) surface area, fraction and dose deposited in the lungs, chemical composition of both particle and gas phase such as NO, NO2, CO, CO2, volatile organic compounds (including aldehydes, benzene, toluene) and polycyclic aromatic hydrocarbons (PAHs). Eyes, nose and throat irritation effects were determined. Exposure conditions with PM1 (<1 μm) mass concentration 280 μg m-3, number concentration 4 × 105 cm-3 and elemental to total carbon fraction of 82% were generated from a diesel vehicle at idling. When estimating the lung deposited dose it was found that using the size dependent effective density (in contrast to assuming unity density) reduced the estimated respiratory dose by 132% by mass. Accounting for agglomerated structure of DEP prevented underestimation of lung deposited dose by surface area by 37% in comparison to assuming spherical particles. Comparison of DE characteristics reported in conducted chamber exposures showed that DE properties vary to a great extent under the same DEP mass concentration and engine load. This highlights the need for detailed and standardized approach for measuring and reporting of DE properties. Eyes irritation effects, most probably caused by aldehydes in the gas phase, as well as nose irritation were observed at exposure levels below current occupational exposure limit

  14. 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.

  15. What Is Radon?

    MedlinePlus

    ... Learn About Cancer » What Causes Cancer? » Other Carcinogens » Pollution » Radon Share this Page Close Push escape to ... can move into the air and into underground water and surface water. Radon is present outdoors and ...

  16. 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.

  17. Dose assessment of population groups exposed to elevated radon levels in radioactive Italian spas

    SciTech Connect

    Sciocchetti, G.; Tosti, S.; Baldassini, P.G.; Sarao, R.; Soldano, E.

    1992-12-31

    The natural spring waters on the Isle of Ischia are among the most radioactive in the world. Therapeutic application of these waters, which contain very high radon concentrations, increases the radon exposure of people treated with them. People who live and work at radioactive spas may be good subjects for testing to evaluate detectable biological effects, especially because their exposures will be less influenced by synergistic factors than those of underground miners. The aim of our investigation was to characterize radon exposure for population groups exposed to high radon levels. Our approach takes into account some peculiar requirements of our epidemiological investigations. To obtain representative dose values, workers were classified into groups to obtain significant results suitable for epidemiological pilot studies. Investigations were carried out on the geological aspects of radon sources, environmental parameters, physical and dosimetric factors which influence radon levels, and related exposures in therapeutic facilities in order to model patterns of radon exposures for the various population groups. We inventoried hyper-radioactive springs on the island. We identified workers in radon spas who were exposed to radiation from inhaled radon daughters and retrospectively assessed their radon exposures. Results showed that, under some conditions, spa employees may have been exposed to much higher than usual levels of radon, which produced up to about 60 mSv y{sup -1} effective dose equivalent.

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

    ERIC Educational Resources Information Center

    Freije, Matthew R.

    1989-01-01

    After a study of 3,000 classrooms in 130 schools in 16 states, the Environmental Protection Agency urged all schools to conduct tests for radon. Explains a 6-step screening test, methods of reducing radon concentrations, and how the risk from radon exposure compares with other risks. (MLF)

  19. Effects of diesel exposure on lung function and inflammation biomarkers from airway and peripheral blood of healthy volunteers in a chamber study

    PubMed Central

    2013-01-01

    Background Exposure to diesel exhaust causes inflammatory responses. Previous controlled exposure studies at a concentration of 300 μg/m3 of diesel exhaust particles mainly lasted for 1 h. We prolonged the exposure period and investigated how quickly diesel exhaust can induce respiratory and systemic effects. Methods Eighteen healthy volunteers were exposed twice to diluted diesel exhaust (PM1 ~300 μg/m3) and twice to filtered air (PM1 ~2 μg/m3) for 3 h, seated, in a chamber with a double-blind set-up. Immediately before and after exposure, we performed a medical examination, spirometry, rhinometry, nasal lavage and blood sampling. Nasal lavage and blood samples were collected again 20 h post-exposure. Symptom scores and peak expiratory flow (PEF) were assessed before exposure, and at 15, 75, and 135 min of exposure. Results Self-rated throat irritation was higher during diesel exhaust than filtered air exposure. Clinical signs of irritation in the upper airways were also significantly more common after diesel exhaust exposure (odds ratio=3.2, p<0.01). PEF increased during filtered air, but decreased during diesel exhaust exposure, with a statistically significant difference at 75 min (+4 L/min vs. -10 L/min, p=0.005). Monocyte and total leukocyte counts in peripheral blood were higher after exposure to diesel exhaust than filtered air 20 h post-exposure, and a trend (p=0.07) towards increased serum IL-6 concentrations was also observed 20 h post-exposure. Conclusions Diesel exhaust induced acute adverse effects such as symptoms and signs of irritation, decreased PEF, inflammatory markers in healthy volunteers. The effects were first seen at 75 min of exposure. PMID:24321138

  20. Radon Update: Facts concerning environmental radon: Levels, mitigation strategies, dosimetry, effects and guidelines

    SciTech Connect

    Brill, A.B.; Becker, D.V.; Donahoe, K.

    1994-02-01

    The risk from environmental radon levels is not higher now than in the past, when residential exposures were not considered to be a significant health hazard. The majority of the radon dose is not from radon itself, but from short-lived alpha-emitting radon daughters, most notably {sup 218}Po (T{sub {1/2}}3min) and {sup 214}Po(T{sub {1/2}}19.7 min). Radon gas can penetrate homes from many sources and in various fashions. Measuring radon in homes is simple and relatively inexpensive and may be accomplished in a variety of ways. Although it is not possible to radon-proof a house, it is possible to reduce the level. In high radon areas, if the average level is higher than 4-8 pCi/liter (NCRP recommended level is 8 pCi/liter; EPA recommmended level is 4 PCi/liter), appropriate action is advised. The shape of the dose response curves for miners exposed to alpha-emitting particles in the workplace is consistent with current biologic knowledge. It is linear in the low dose range and saturates in the high dose range. No detectable increase in lung cancer frequency is seen in the lowest exposed miners (those with exposures <120 WLM, the relevant dose interval for most homes). Evidence for a health effect from radon exposure is based on data from animal studies and epidemiologic studies of mines. Extensive radiobiologic data predict a linear dose-response curve in the low dose region due to poor biological repair mechanisms for the high density of ionizing events that alpha particles create. However, no compelling evidence for increased cancer risks has yet been demonstrated from {open_quotes}acceptable{close_quotes}levels (<4-8 pCi/liter). 58 refs., 11 figs., 12 tabs.

  1. A COMPARISON OF WINTER SHORT-TERM AND ANNUAL AVERAGE RADON MEASUREMENTS IN BASEMENTS OF A RADON-PRONE REGION AND EVALUATION OF FURTHER RADON TESTING INDICATORS

    PubMed Central

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

    2014-01-01

    The primary objective of this study was to investigate the temporal variability between basement winter short-term (7 to 10 days) and basement annual radon measurements. Other objectives were to test the short-term measurement’s diagnostic performance at two reference levels and to evaluate its ability to predict annual average basement radon concentrations. Electret ion chamber (short-term) and alpha track (annual) radon measurements were obtained by trained personnel in Iowa residences. Overall, the geometric mean of the short-term radon concentrations (199 Bq m−3) was slightly greater than the geometric mean of the annual radon concentrations (181 Bq m−3). Short-term tests incorrectly predicted that the basement annual radon concentrations would be below 148 Bq m−3 12% of the time and 2% of the time at 74 Bq m−3. The short-term and annual radon concentrations were strongly correlated (r=0.87, p<0.0001). The foundation wall material of the basement was the only significant factor to have an impact on the absolute difference between the short-term and annual measurements. The findings from this study provide evidence of a substantially lower likelihood of obtaining a false negative result from a single short-term test in a region with high indoor radon potential when the reference level is lowered to 74 Bq m−3. PMID:24670901

  2. 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.

  3. Radon and climatic multiparameter analysis: A one-year study on radon dynamics in a house

    SciTech Connect

    Genrich, V.

    1995-12-31

    Radon-reduction in private and public buildings is a current issue. Research has opened our eyes for the enormous fluctuations of the indoor radon level over longer observation periods. For generalizing the behavior radon in a building, care must be taken that the observation period is long enough, to mediate the pronounced climatic changes in the course of a year. The author has started a one-year observations, precisely logging up the radon level in a single family home. Six portable multiparameter-monitors, each equipped with a 0.6 liter PIC-detector (PIC = pulse ionization chamber), have been installed at different locations within the building and outdoors (incl. two soil-gas probes). Besides the radon concentration, in the same instruments the following parameters are logged cotinuously: relative humidity, differential pressure between basement and sub-slab area, soil impendance (indication water saturation) and wind speed on the roof. In the basement, the radon concentration varies between 61 Bq/m{sup 3} and 5408 Bq/m{sup 3} (mean: 1092 Bq/m{sup 3}.) By analyzing these records, the time sequence of the radon concentration can be characterized as a {open_quotes}mixture{close_quotes} of (periodic) circadian variations overlayed with (aperiodic) seasonal fluctuations. In this building, it turns out, that the pressure difference across the base plate is an important factor for radon entry as well as ventilation rate. It can be shown, that the pressure is closely related to the indoor-outdoor temperature difference. This relation was found to be non-linear. Other factors are attributed to the activities of the inhabitants. The paper points out correlations between radon and different climatic parameters mainly by using scatterplots and classical regression methods.

  4. Headspace stir bar sorptive extraction-gas chromatography/mass spectrometry characterization of the diluted vapor phase of cigarette smoke delivered to an in vitro cell exposure chamber.

    PubMed

    Kaur, Navneet; Cabral, Jean-Louis; Morin, André; Waldron, Karen C

    2011-01-14

    Advanced smoke generation systems, such as the Borgwaldt RM20S(®) smoking machine used in combination with the BAT exposure chamber, allow for the generation, dilution and delivery of fresh cigarette smoke to cell or tissue cultures for in vitro cell culture analyses. Recently, our group confirmed that the Borgwaldt RM20S(®) is a reliable tool to generate and deliver repeatable and reproducible exposure concentrations of whole smoke to in vitro cultures. However, the relationship between dose and diluted smoke components found within the exposure chamber has not been characterized. The current study focused on the development of a headspace stir bar sorptive extraction (HSSE) method to chemically characterize some of the vapor phase components of cigarette smoke generated by the Borgwaldt RM20S(®) and collected within a cell culture exposure chamber. The method was based on passive sampling within the chamber by HSSE using a Twister™ stir bar. Following exposure, sorbed analytes were recovered using a thermal desorption unit and a cooled injection system coupled to gas chromatograph/mass spectrometry for identification and quantification. Using the HSSE method, sixteen compounds were identified. The desorption parameters were assessed using ten reference compounds and the following conditions led to the maximal response: desorption temperature of 200°C for 2 min with cryofocussing temperature of -75°C. During transfer of the stir bars to the thermal desorption system, significant losses of analytes were observed as a function of time; therefore, the exposure-to-desorption time interval was kept at the minimum of 10±0.5 min. Repeatability of the HSSE method was assessed by monitoring five reference compounds present in the vapor phase (10.1-12.9% RSD) and n-butyl acetate, the internal standard (18.5% RSD). The smoke dilution precision was found to be 17.2, 6.2 and 11.7% RSD for exposure concentrations of 1, 2 and 5% (v/v) cigarette vapor phase in air

  5. Estimation of radon concentration in dwellings in and around Guwahati

    NASA Astrophysics Data System (ADS)

    Dey, Gautam Kumar; Das, Projit Kumar

    2012-02-01

    It has been established that radon and its airborne decay products can present serious radiation hazards. A long term exposure to high concentration of radon causes lung cancer. Besides, it is also known that out of the total radiation dose received from natural and man-made sources, 60% of the dose is due to radon and its progeny. Taking this into account, an attempt has been made to estimate radon concentration in dwellings in and around Guwahati using aluminium dosimeter cups with CR-39 plastic detectors. Results of preliminary investigation presented in this paper show that the mean concentration is 21.31 Bq m - 3.

  6. Variations in radon concentration in groundwater of Kumaon Himalaya, India.

    PubMed

    Bourai, A A; Gusain, G S; Rautela, B S; Joshi, V; Prasad, G; Ramola, R C

    2012-11-01

    The radon content in groundwater sources depends on the radium concentration in the rock of the aquifer. Radon was measured in water in many parts of the world, mostly for the risk assessment due to consumption of drinking water. The exposure to radon through drinking water is largely by inhalation and ingestion. Airborne radon can be released during normal household activities and can pose a greater potential health risk than radon ingested with water. Transport of radon through soil and bedrock by water depends mainly on the percolation of water through the pores and along fracture planes of bedrock. In this study, the radon concentration in water from springs and hand pumps of Kumaun Himalaya, India was measured using the radon emanometry technique. Radon concentration was found to vary from 1 to 392 Bq l(-1) with a mean of 50 Bq l(-1) in groundwater in different lithotectonic units. The radon level was found to be higher in the area consisting of granite, quartz porphyry, schist, phyllites and lowest in the area having sedimentary rocks, predominantly dominated by quartzite rocks.

  7. Variations in radon concentration in groundwater of Kumaon Himalaya, India.

    PubMed

    Bourai, A A; Gusain, G S; Rautela, B S; Joshi, V; Prasad, G; Ramola, R C

    2012-11-01

    The radon content in groundwater sources depends on the radium concentration in the rock of the aquifer. Radon was measured in water in many parts of the world, mostly for the risk assessment due to consumption of drinking water. The exposure to radon through drinking water is largely by inhalation and ingestion. Airborne radon can be released during normal household activities and can pose a greater potential health risk than radon ingested with water. Transport of radon through soil and bedrock by water depends mainly on the percolation of water through the pores and along fracture planes of bedrock. In this study, the radon concentration in water from springs and hand pumps of Kumaun Himalaya, India was measured using the radon emanometry technique. Radon concentration was found to vary from 1 to 392 Bq l(-1) with a mean of 50 Bq l(-1) in groundwater in different lithotectonic units. The radon level was found to be higher in the area consisting of granite, quartz porphyry, schist, phyllites and lowest in the area having sedimentary rocks, predominantly dominated by quartzite rocks. PMID:22914330

  8. Ambient Radon-222 Monitoring in Amargosa Valley, Nevada

    SciTech Connect

    L.H. Karr; J.J. Tappen; D. Shafer; K.J. Gray

    2008-06-05

    As part of a program to characterize and baseline selected environmental parameters in the region around the proposed repository at Yucca Mountain, Nevada, ambient radon-222 monitoring was conducted in the rural community of Amargosa Valley, the community closest to the proposed repository site. Passive integrating radon monitors and a continuous radon monitoring instrument were deployed adjacent to the Community Environmental Monitoring Program (CEMP) (http://www.cemp.dri.edu/index.html) station located in the Amargosa Valley Community Center near the library. The CEMP station provided real-time ambient gamma exposure and meteorological data used to correct the integrated radon measurements as well as verify meteorological data collected by the continuous radon monitoring instrument. Additionally, different types of environmental enclosures that housed the monitors and instrument were used to determine if particular designs influenced the ambient radon measurements.

  9. The performance of charcoal-based radon detection under time-varying radon conditions: Experimental and theoretical results

    SciTech Connect

    Sextro, R.G.; Lee, D.D.

    1988-10-01

    Radon adsorption by charcoal is a widely used technique for measuring indoor radon concentration, particularly when short-term results are desired. There are several different devices available, ranging from permeable envelopes filled with charcoal and open-face charcoal-filled canisters to devices incorporating diffusion limiting features to reduce losses of radon due to desorption. However, the integration characteristics of these samplers are not well understood, particularly under conditions of highly varying radon concentrations. A model for predicting the response of various types of charcoal based detectors to time-variant radon concentrations has been developed; the model predictions compare well with results from chamber experiments. Both the experimental and theoretical results have also been compared with integrated continuous-sampling measurements. The implications of these comparisons for use of charcoal for screening measurements is discussed. 5 refs., 4 figs., 2 tabs.

  10. 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. PMID:24106330

  11. 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.

  12. Radon and lung cancer

    SciTech Connect

    Samet, J.M.

    1989-05-10

    Radon, an inert gas released during the decay of uranium-238, is ubiquitous in indoor and outdoor air and contaminates many underground mines. Extensive epidemiologic evidence from studies of underground miners and complementary animal data have documented that radon causes lung cancer in smokers and nonsmokers. Radon must also be considered a potentially important cause of lung cancer for the general population, which is exposed through contamination of indoor air by radon from soil, water, and building materials. This review describes radon's sources, levels in U.S. homes, dosimetry, the epidemiologic evidence from studies of miners and the general population, and the principal, recent risk assessments.91 references.

  13. Radon and lung cancer.

    PubMed

    Samet, J M

    1989-05-10

    Radon, an inert gas released during the decay of uranium-238, is ubiquitous in indoor and outdoor air and contaminates many underground mines. Extensive epidemiologic evidence from studies of underground miners and complementary animal data have documented that radon causes lung cancer in smokers and nonsmokers. Radon must also be considered a potentially important cause of lung cancer for the general population, which is exposed through contamination of indoor air by radon from soil, water, and building materials. This review describes radon's sources, levels in U.S. homes, dosimetry, the epidemiologic evidence from studies of miners and the general population, and the principal, recent risk assessments.

  14. Radon is out

    SciTech Connect

    Harley, J.H.

    1992-12-31

    This paper discusses some facets of outdoor radon. There is only one source of radon - the decay of radium. Radium is everywhere but the bulk is in soil, rock, and ocean sediments. Soil porosity is a prime factor in radon movement. Exhalation from soil is fed by the high concentrations of radon in soil gas. Because the surface soil is losing radon to the atmosphere, soil gas concentration would be expected to increase with depth. There is a wide range of air radon concentrations, with marked seasonal and diurnal variations. Atmospheric stability is certainly a major factor - radon increases during inversions and decreases when the inversion breaks up. In addition, temperature, soil moisture, snow cover, and wind direction all play a part. Different investigators sometimes come to contrary conclusions on the effects of these factors. They are probably all correct - for the conditions in effect at the time - since no simple generalities exist for most factors.

  15. Radon optical processing in radon space

    NASA Astrophysics Data System (ADS)

    Barrett, H. H.

    1986-06-01

    The stated goals of the Radon program were: (1) Theoretical investigation of the role of the Radon transform in signal processing, including enumeration of the operations achievable in Radon space. (2) Construction of a practical system for two dimensional spectral analysis and image filtering. (3) Proof-of-principle experiments for other processing operations, such as bandwidth compression and calculation of the Wigner distribution function. (4) Determination of the feasibility of Radon-space processing of three dimensional data, emphasizing not only system architecture but also storage media capable of saving rapidly retrieving the requisite data arrays. Several 2D signal-processing operations are discovered susceptible to solution in Radon space. These include the Hartley transform, certain joint coordinate-frequency representations (e.g., the Wigner distribution function and Woodward ambiguity functions), certain algorithms for spectrum estimation (e.g., the periodogram and the Yule Walker autoregressive model), and the cepstrum. Most of these Radon space operations have been demonstrated in computer simulations and some have been performed by means of analog hardware in the hybrid Radon space signal processing system. This system can perform a family of processing operations at about five frames per second, limited by the image-rotation rate. Processing is performed by surface acoustic wave (SAW) filters, and the 2D processed signal is displayed on a CRT.

  16. EPA`s approach to assessment of radon risk

    SciTech Connect

    Schmidt, A.; Puskin, J.S.; Nelson, N.; Nelson, C.B.

    1992-12-31

    The Environmental Protection Agency (EPA) has assessed the potential lung-cancer risk to the general population due to radon based on the Agency`s general principles of risk assessment. This same approach has been used to assess the impact on public health of other carcinogenic environmental pollutants. This paper briefly describes the application of EPA`s approach to radon and includes a description of the method used by the Agency to estimate that approximately 22,000 lung-cancer deaths per year may be related to radon exposure. Also presented are the weight of evidence for classifying radon as a known human carcinogen and the uncertainties associated with estimating risks from radon exposure. These combined factors reflect the extent of the underlying support and the context for EPA`s estimates of lung-cancer deaths.

  17. Calibration of the Politrack® system based on CR39 solid-state nuclear track detectors for passive indoor radon concentration measurements.

    PubMed

    Kropat, G; Baechler, S; Bailat, C; Barazza, F; Bochud, F; Damet, J; Meyer, N; Palacios Gruson, M; Butterweck, G

    2015-11-01

    Swiss national requirements for measuring radon gas exposures demand a lower detection limit of 50 kBq h m(-3), representing the Swiss concentration average of 70 Bq m(-3) over a 1-month period. A solid-state nuclear track detector (SSNTD) system (Politrack, Mi.am s.r.l., Italy) has been acquired to fulfil these requirements. This work was aimed at the calibration of the Politrack system with traceability to international standards and the development of a procedure to check the stability of the system. A total of 275 SSNTDs was exposed to 11 different radon exposures in the radon chamber of the Secondary Calibration Laboratory at the Paul Scherrer Institute, Switzerland. The exposures ranged from 50 to 15000 kBq h m(-3). For each exposure of 20 detectors, 5 SSNTDs were used to monitor possible background exposures during transport and storage. The response curve and the calibration factor of the whole system were determined using a Monte Carlo fitting procedure. A device to produce CR39 samples with a reference number of tracks using a (241)Am source was developed for checking the long-term stability of the Politrack system. The characteristic limits for the detection of a possible system drift were determined following ISO Standard 11929.

  18. Radon entry control in new house construction

    SciTech Connect

    Najafi, F.T.; Lalwani, L.; Li, W.G.

    1995-07-01

    People exposed to high concentration levels of radon face an increased risk of developing lung cancer. The risk is directly proportional to the length and level of radon exposure. Because of health reasons, it is safer to build new houses with radon mitigation systems installed in slab-on-grade houses. However, the interrelationships between parameters and factors governing radon entry and control are highly complex. A study performed by the University of Florida has examined the effectiveness of different radon entry control approaches. The analysis was based on 47 houses from three research projects conducted by the University of Florida (14 houses), Florida Solar Energy Center (13 houses), and GEOMET Technologies (20 houses). The evaluation of the performance and effectiveness of improved floor slabs, space conditioning, and ventilating systems were analyzed. Statistical analyses of the interrelationship between various parameters were also performed. Study findings such as the important factors in reducing radon entry and the effectiveness of passive construction approach and active subslab depressurization systems are presented in this paper. 9 refs., 10 figs., 3 tabs.

  19. Atmosphere purification of radon and radon daughter elements

    DOEpatents

    Stein, L.

    1974-01-01

    A method of removing radon and radon daughter elements from an atmosphere containing these elements by passing the atmosphere through a bed of fluorinating compound whereby the radon and radon daughters are oxidized to their respective fluorides is discussed. These fluorides adhere to the fluorinating compound and are thus removed from the atmosphere which may then be recirculated. A method for recovering radon and separating radon from its daughter elements is also described. (Official Gazette)

  20. Radon and radon progeny outdoors in a valley of enhanced natural radioactivity

    NASA Astrophysics Data System (ADS)

    Pressyanov, Dobromir S.; Guelev, Methody G.; Sharkov, Borislav G.

    Results of a pilot study of 222Rn and 222Rn progeny outdoors and indoors in a valley of enhanced radioactivity, affected by uranium mining and milling have been summarized. Diurnal and spatial variations have been followed, and 222Rn concentrations in soil-gas have been determined. High outdoor concentrations of radon progeny during nights and at early mornings have been observed under the conditions of high air stagnation. The indoor concentrations were greater than the outdoor ones, however in most of the studied houses, the contribution of outdoor radon to the total exposure was found to be dominating. The cumulative exposure (for over 90% of the inhabitants) due to outdoor radon was estimated to be about 0.9 WLM per annum. These results reveal that lung-cancer risk excess by about 80% could be attributed to outdoor radon, provided that one assumes the risk coefficients (the cancer risk per unit of exposure) determined for occupational exposures. The study of different radon sources suggests that except for the uranium mining and milling, the generally enhanced natural radioactivity and meteorological conditions in this valley are of substantial importance. Valleys, such as the questioned one, may give an opportunity to check up the hypothesis about the existence of health effects at low doses of 222Rn progeny exposure.

  1. 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.

  2. Radon levels in underground workplaces: a map of the Italian regions.

    PubMed

    Rossetti, Marta; Esposito, Massimo

    2015-04-01

    The indoor radon exposition is a widely recognised health hazard, so specific laws and regulations have been produced in many countries and so-called radon-risk maps have consequently been produced. In Italy the regulation applies to general workplaces and a national survey was carried out in the 1990s to evaluate the exposure to radon in dwellings. Failing a national coordinated mapping programme, some Italian regions performed a survey to identify radon-prone areas, nevertheless with different methodologies. In this work a national map of the average annual radon concentration levels in underground workplaces, obtained from the results of 8695 annual indoor radon measurements carried out by U-Series laboratory between 2003 and 2010, was presented. Due to underground locations, the mean radon concentration is higher than that from previous map elaborated for dwellings and a significant radon concentration was also found in Regions traditionally considered as low-risk areas.

  3. Bakeout Chamber Within Vacuum Chamber

    NASA Technical Reports Server (NTRS)

    Taylor, Daniel M.; Soules, David M.; Barengoltz, Jack B.

    1995-01-01

    Vacuum-bakeout apparatus for decontaminating and measuring outgassing from pieces of equipment constructed by mounting bakeout chamber within conventional vacuum chamber. Upgrade cost effective: fabrication and installation of bakeout chamber simple, installation performed quickly and without major changes in older vacuum chamber, and provides quantitative data on outgassing from pieces of equipment placed in bakeout chamber.

  4. Preliminary results regarding the first map of residential radon in some regions in Romania.

    PubMed

    Cosma, C; Cucoş Dinu, A; Dicu, T

    2013-07-01

    Radon represents the most important contribution of population exposure to natural ionising radiation. This article presents the first indoor radon map in some regions of Romania based on 883 surveyed buildings in the Ştei-BăiŢa radon-prone region and 864 in other regions of Romania. Indoor radon measurements were performed in the last 10 y by using CR-39 nuclear track detectors exposed for 3-12 months on ground floor levels of dwellings. Excluding the Ştei-BăiŢa radon-prone region, an average indoor radon concentration of 126 Bq m(-3) was calculated for Romanian houses. In the Ştei-BăiŢa radon-prone area, the average indoor concentration was 292 Bq m(-3). About 21 % of the investigated dwellings in the Ştei-BăiŢa radon-prone region exceed the threshold of 400 Bq m(-3), while 5 % of the dwellings in other areas of Romania exceed the same threshold. As expected, indoor radon concentration is not uniformly distributed throughout Romania. The map shows a high variability among surveyed regions, mainly due to the differences in geology. The radon emanation rate is substantially influenced by the soil characteristics, such as the soil permeability and soil gas radon concentration. Since higher permeability enables the increased migration of soil gas and radon from the soil into the building, elevated levels of indoor radon can be expected in more permeable soil environments.

  5. Mineral dusts and radon in uranium mines

    SciTech Connect

    Abelson, P.H.

    1991-11-08

    The Environmental Protection Agency (EPA) continues to assert that radon is a major cause of lung cancer in this country. EPA is fostering a radon program that could entail huge financial and emotional costs while yielding negligible benefits to public health. Justification for the program was the occurrence of lung cancer in men exposed to huge amounts of radon, mineral dusts, and other lung irritants in uranium mines on the Colorado Plateau. Lung cancer has been reported in about 356 cigarette smokers and in about 25 nonsmokers. During the era of high radon levels, monitoring was sporadic. Conditions in only a small fraction of the mines were measured, and that on a few separate occasions. Later, cumulative exposure to radon was calculated on the basis of measurements involving only a tiny fraction of the miners. Some were exposed to more than 15,000 pCi/liter of radon and its products. The level in the average home is about 1.5 pCi/liter. In making extrapolations from mine to home, the assumption is made that residents are in their dwellings most of the time and that miners spend only 170 hours a month in the mine. Two major questionable assumptions are involved in extrapolations from high doses of radon in the mines to low doses in homes. One is that no threshold is involved; that is, that humans have no remediation mechanism for {alpha} particle damages. There is evidence to the contrary. The most unrealistic assumption is that heavy exposure to silica has no effect on inducing lung cancer. Many studies have shown that silica dust causes lung cancer in animals. Exposure of human culture cells to silica has resulted in formation of neoplastic tissue. EPA has no solid evidence that exposures to 4 pCi/liter of radon causes lung cancer in either smokers or nonsmokers. Indeed, there is abundant evidence to the contrary in the fact that in states with high levels of radon, inhabitants have less lung cancer than those in states with low levels.

  6. Residential Radon and Brain Tumour Incidence in a Danish Cohort

    PubMed Central

    Bräuner, Elvira V.; Andersen, Zorana J.; Andersen, Claus E.; Pedersen, Camilla; Gravesen, Peter; Ulbak, Kaare; Hertel, Ole; Loft, Steffen; Raaschou-Nielsen, Ole

    2013-01-01

    Background Increased brain tumour incidence over recent decades may reflect improved diagnostic methods and clinical practice, but remain unexplained. Although estimated doses are low a relationship between radon and brain tumours may exist. Objective To investigate the long-term effect of exposure to residential radon on the risk of primary brain tumour in a prospective Danish cohort. Methods During 1993–1997 we recruited 57,053 persons. We followed each cohort member for cancer occurrence from enrolment until 31 December 2009, identifying 121 primary brain tumour cases. We traced residential addresses from 1 January 1971 until 31 December 2009 and calculated radon concentrations at each address using information from central databases regarding geology and house construction. Cox proportional hazards models were used to estimate incidence rate-ratios (IRR) and 95% confidence intervals (CI) for the risk of primary brain tumours associated with residential radon exposure with adjustment for age, sex, occupation, fruit and vegetable consumption and traffic-related air pollution. Effect modification by air pollution was assessed. Results Median estimated radon was 40.5 Bq/m3. The adjusted IRR for primary brain tumour associated with each 100 Bq/m3 increment in average residential radon levels was 1.96 (95% CI: 1.07; 3.58) and this was exposure-dependently higher over the four radon exposure quartiles. This association was not modified by air pollution. Conclusions We found significant associations and exposure-response patterns between long-term residential radon exposure radon in a general population and risk of primary brain tumours, adding new knowledge to this field. This finding could be chance and needs to be challenged in future studies. PMID:24066143

  7. Radon exhalation from building materials for decorative use.

    PubMed

    Chen, Jing; Rahman, Naureen M; Abu Atiya, Ibrahim

    2010-04-01

    Long-term exposure to radon increases the risk of developing lung cancer. There is considerable public concern about radon exhalation from building materials and the contribution to indoor radon levels. To address this concern, radon exhalation rates were determined for 53 different samples of drywall, tile and granite available on the Canadian market for interior home decoration. The radon exhalation rates ranged from non-detectable to 312 Bq m(-2) d(-1). Slate tiles and granite slabs had relatively higher radon exhalation rates than other decorative materials, such as ceramic or porcelain tiles. The average radon exhalation rates were 30 Bq m(-2) d(-1) for slate tiles and 42 Bq m(-2) d(-1) for granite slabs of various types and origins. Analysis showed that even if an entire floor was covered with a material having a radon exhalation rate of 300 Bq m(-2) d(-1), it would contribute only 18 Bq m(-3) to a tightly sealed house with an air exchange rate of 0.3 per hour. Generally speaking, building materials used in home decoration make no significant contribution to indoor radon for a house with adequate air exchange.

  8. Validation of an original incubator set-up for the exposure of human astrocyte cells to X-band microwaves in a GTEM-chamber.

    PubMed

    Pérez-Bruzón, R N; Del Moral, A; Pérez-Castejón, C; Llorente, M; Vera, A; Azanza, M J

    2011-09-01

    A current concern about the biological effects of electromagnetic fields (EMF) is increasing with the wide spread use of X-band microwaves (MW, 8-10 GHz range). Gigahertz transverse electromagnetic (GTEM) field flat transmission lines are currently being used for experimental exposure of biological samples to high frequency EMF. Experiments carried out on human cells in culture require optimal growing temperature conditions, i.e. 37 °C, 5% CO2 in a humidified atmosphere. The aim of our work has been: i) to built up an original incubator set-up, the so called GTEM-incubator, for exposure of human cells in culture to MW inside a GTEM-chamber, under optimal growing physical conditions; ii) to make the validation of the GTEM-incubator by growing cell samples inside the non-energized GTEM-chamber (test sample) comparing the results with the ones obtained from cell samples grown inside a standard incubator (control samples). The features for comparison were: cell morphology, expression and distribution of cytoskeleton proteins, genotoxicity, viability and cell cycle progression. Any variation in any of the studied parameters would allow for detecting any possible failure or misconception in our GTEM-incubator working test. The results obtained in control and test incubators showed non-significant differences in the development of both cell populations for any of the studied parameters. Thereby our GTEM-incubator is considered valid for our purposes of human cell exposures to X-band MW.

  9. Studies of indoor radon and lung cancer risk

    SciTech Connect

    Lubin, J.H.

    1997-03-01

    Epidemiologic case-control studies reported to date have not consistently shown an association between indoor radon and lung cancer risk, even though studies of radon-exposed underground miners have conclusively shown that exposure to radon and its progeny causes lung cancer. Some have interpreted this seeming inconsistency as evidence that exposure to radon at the levels typically found in homes does not cause lung cancer; that exposure in homes causes lung cancer but not to the extent estimated from miner-based risk models; or that risk among miners is dominated by smoking or by other exposures, and miner-based risk models are therefore not relevant to residential exposures. The inconsistency of results has led to claims that indoor radon may not pose a significant public health hazard and that current risk management approaches may not be justified. This paper examines current indoor radon studies. Results from current studies are presented, and then followed by computer simulations, which illustrate the impact of mobility and exposure misclassification. Finally, results of a meta-analysis of indoor studies are presented that suggest that RRs are consistent with miner-based extrapolations and with a small excess risk from indoor exposures, but that there remains unexplained heterogeneity among the studies.

  10. Radon assay and purification techniques

    SciTech Connect

    Simgen, Hardy

    2013-08-08

    Radon is a source of background in many astroparticle physics experiments searching for rare low energy events. In this paper an overview about radon in the field is given including radon detection techniques, radon sources and material screening with respect to radon emanation. Finally, also the problem of long-lived radioactive {sup 222}Rn-daughters and the question of gas purification from radon is addressed.

  11. Radon-hazard potential the Beaver basin, Utah

    SciTech Connect

    Bishop, C.E.

    1995-06-01

    Indoor-radon levels in the Beaver basin of southwestern Utah are the highest recorded to date in Utah, ranging from 17.5 to 495 picocuries per liter (pCi/L). Because the U.S. Environment Protection Agency considers indoor-radon levels above 4 pCi/L to represent a risk of lung cancer from long-term exposure, the Utah Geological Survey is preparing a radon-hazard-potential map for the area to help prioritize indoor testing and evaluate the need for radon-resistant construction. Radon is a chemically inert radioactive gas derived from the decay of uranium-238, which is commonly found in rocks and soils. Soil permeability, depth to ground water, and uranium/thorium content of source materials control the mobility and concentration of radon in the soil. Once formed, radon diffuses into the pore space of the soil and then to the atmosphere or into buildings by pressure-driven flow of air or additional diffusion. The Beaver basin has been a topographic and structural depression since late Miocene time. Paleocene to Miocene volcanic and igneous rocks border the basin. Uraniferous alluvial-fan, piedmont-slope, flood-plain, and lacustrine sediments derived from the surrounding volcanic rocks fill the basin. A soil-gas radon and ground radioactivity survey in the Beaver basin shows that soils have high levels of radon gas. In this survey, uranium concentrations range from 3 to 13 parts per million (ppm) and thorium concentrations range from 10 to 48 ppm. Radon concentrations in the soil gas ranged from 85 to 3,500 pCi/L. The highest concentrations of uranium, thorium, and radon gas and the highest radon-hazard-potential are in the well-drained permeable soils in the lower flood- plain deposits that underlie the city of Beaver.

  12. Portable apparatus for the measurement of environmental radon and thoron

    DOEpatents

    Negro, Vincent C.

    2001-01-01

    The radometer is a portable instrument for the measurement of the concentration of atmospheric radon/thoron in a test area. A constant velocity pump pulls the air from the outside at a constant flow rate. If the air is too moist, some or all of the sample is passed through a desiccant filter prior to encountering an electrostatic filter. The electrostatic filter prevents any charged particles from entering the sampling chamber. Once the sample has entered the chamber, the progeny of the decay of radon/thoron are collected on a detector and measured. The measured data is compiled by a computer and displayed.

  13. Potential for bias in epidemiologic studies that rely on glass-based retrospective assessment of radon

    SciTech Connect

    Weinberg, C.R.

    1995-11-01

    Retrospective assessment of exposure to radon remains the greatest challenge in epidemiologic efforts to assess lung cancer risk associated with residential exposure. An innovative technique based on measurement of {alpha}-emitting, long-lived daughters embedded by recoil into household glass may one day provide improved radon dosimetry. Particulate air pollution is known, however, to retard the plate-out of radon daughters. This would be expected to result in a differential effect on dosimetry, where the calibration curve relating the actual historical radon exposure to the remaining {alpha}-activity in the glass would be different in historically smoky and nonsmoky environments. The resulting {open_quotes}measurement confounding{close_quotes} can distort inferences about the effect of radon and can also produce spurious evidence for synergism between radon exposure and cigarette smoking. 18 refs., 4 figs.

  14. Potential for bias in epidemiologic studies that rely on glass-based retrospective assessment of radon.

    PubMed Central

    Weinberg, C R

    1995-01-01

    Retrospective assessment of exposure to radon remains the greatest challenge in epidemiologic efforts to assess lung cancer risk associated with residential exposure. An innovative technique based on measurement of alpha-emitting, long-lived daughters embedded by recoil into household glass may one day provide improved radon dosimetry. Particulate air pollution is known, however, to retard the plate-out of radon daughters. This would be expected to result in a differential effect on dosimetry, where the calibration curve relating the actual historical radon exposure to the remaining alpha-activity in the glass would be different in historically smoky and nonsmoky environments. The resulting "measurement confounding" can distort inferences about the effect of radon and can also produce spurious evidence for synergism between radon exposure and cigarette smoking. Images Figure 1. Figure 2. Figure 3. Figure 4. PMID:8605854

  15. Results of simultaneous radon and thoron measurements in 33 metropolitan areas of Canada.

    PubMed

    Chen, Jing; Bergman, Lauren; Falcomer, Renato; Whyte, Jeff

    2015-02-01

    Radon has been identified as the second leading cause of lung cancer after tobacco smoking. (222)Rn (radon gas) and (220)Rn (thoron gas) are the most common isotopes of radon. In order to assess thoron contribution to indoor radon and thoron exposure, a survey of residential radon and thoron concentrations was initiated in 2012 with ∼4000 homes in the 33 census metropolitan areas of Canada. The survey confirmed that indoor radon and thoron concentrations are not correlated and that thoron concentrations cannot be predicted from widely available radon information. The results showed that thoron contribution to the radiation dose varied from 0.5 to 6% geographically. The study indicated that, on average, thoron contributes ∼3% of the radiation dose due to indoor radon and thoron exposure in Canada. Even though the estimated average thoron concentration of 9 Bq m(-3) (population weighted) in Canada is low, the average radon concentration of 96 Bq m(-3) (population weighted) is more than double the worldwide average indoor radon concentration. It is clear that continued efforts are needed to further reduce the exposure and effectively reduce the number of lung cancers caused by radon.

  16. 30 CFR 57.5040 - Exposure records.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) The operator shall calculate and record complete individual exposures to concentrations of radon... concentration of airborne radon daughters for each active working area. (2) Where uranium is not mined—the complete individual exposure of all mine personnel working in active working areas with radon...

  17. 30 CFR 57.5040 - Exposure records.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) The operator shall calculate and record complete individual exposures to concentrations of radon... concentration of airborne radon daughters for each active working area. (2) Where uranium is not mined—the complete individual exposure of all mine personnel working in active working areas with radon...

  18. 30 CFR 57.5040 - Exposure records.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) The operator shall calculate and record complete individual exposures to concentrations of radon... concentration of airborne radon daughters for each active working area. (2) Where uranium is not mined—the complete individual exposure of all mine personnel working in active working areas with radon...

  19. 30 CFR 57.5040 - Exposure records.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) The operator shall calculate and record complete individual exposures to concentrations of radon... concentration of airborne radon daughters for each active working area. (2) Where uranium is not mined—the complete individual exposure of all mine personnel working in active working areas with radon...

  20. 30 CFR 57.5040 - Exposure records.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) The operator shall calculate and record complete individual exposures to concentrations of radon... concentration of airborne radon daughters for each active working area. (2) Where uranium is not mined—the complete individual exposure of all mine personnel working in active working areas with radon...

  1. Epidemiological implications of spatial and temporal radon variations

    SciTech Connect

    Steck, D.J.; Lively, R.S.; Ney, E.P.

    1992-12-31

    Epidemiological studies require accurate assessments of total radon-daughter exposures. Short-term radon measurements taken in current dwellings may misrepresent past exposures. In the upper midwest, we have observed significant spatial variation, on a scale of several kilometers, in yearly average indoor radon concentrations. Thus, ecological studies using small samples, or case-control studies using only the current residences for exposure assessment, could misjudge the actual long-term exposures if the size of the geographical cluster used is larger than a county. Short-term measurements also may introduce unacceptable variation. In a comparison of two measurement techniques in 80 upper-midwest homes, a correlation was found between year-long alpha-track and 2-day charcoal canister measurements. However, the observed coefficient of variation (factor of two) between measurement protocols may introduce enough scatter to obscure weak correlations in small samples. A correlation that was observed between lung-cancer rates in 13 rural Minnesota counties and the annual-average radon concentration (median = 100 Bq m{sup {minus}3}) estimated from year-long alpha-track measurements was not found when charcoal canister data were used to estimate the radon exposure. Year-to-year variations may also be important. In 12 homes that have been monitored for longer than 1 y, yearly variations ranged from 0 to 500%, with a median variation of 22%. We are investigating a retrospective detection technique that may improve long-term radon exposure assessments. We have found correlation between the surface alpha activity and radon exposure for glass surfaces exposed from 6 to 2000 kBq y m{sup {minus}3}. We have developed an alpha-track detection system that measures both current radon concentrations and exposure history.

  2. Risks from Radon: Reconciling Miner and Residential Epidemiology

    NASA Astrophysics Data System (ADS)

    Chambers, Douglas B.; Harley, Naomi H.

    2008-08-01

    Everyone is exposed to radon, an inert radioactive gas that occurs naturally and is present everywhere in the atmosphere. The annual dose from radon and its (short-lived) decay products is typically about one-half of the dose received by members of the public from all natural sources of ionizing radiation. Data on exposures and consequent effects have recently been reviewed by the National Council on Radiation Protection and Measurements (NCRP) and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Studies of underground miners provides a well-established basis for estimating risks from occupational exposures to radon and for studying factors that may affect the dose response relationship such as the reduction of risk (coefficients) with increasing time since exposure. Miners' studies previously formed the basis for estimating risks to people exposed to radon at home, with downward extrapolation from exposures in mines to residential levels of radon. Presently, the risk estimates from residential studies are adequate to estimate radon risks in homes. Although there are major uncertainties in extrapolating the risks of exposure to radon from the miner studies to assessing risks in the home, there is remarkably good agreement between the average of risk factors derived from miner studies and those from pooled residential case-control studies. There are now over 20 analytical studies of residential radon and lung cancer. These studies typically assess the relative risk from exposure to radon based on estimates of residential exposure over a period of 25 to 30 years prior to diagnosis of lung cancer. Recent pooled analyses of residential case-control studies support a small but detectable lung cancer risk from residential exposure, and this risk increases with increasing concentrations. The excess relative risk of lung cancer from long-term residential exposure is about the same for both smokers and non-smokers; however, because the

  3. Risks from Radon: Reconciling Miner and Residential Epidemiology

    SciTech Connect

    Chambers, Douglas B.; Harley, Naomi H.

    2008-08-07

    Everyone is exposed to radon, an inert radioactive gas that occurs naturally and is present everywhere in the atmosphere. The annual dose from radon and its (short-lived) decay products is typically about one-half of the dose received by members of the public from all natural sources of ionizing radiation. Data on exposures and consequent effects have recently been reviewed by the National Council on Radiation Protection and Measurements (NCRP) and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Studies of underground miners provides a well-established basis for estimating risks from occupational exposures to radon and for studying factors that may affect the dose response relationship such as the reduction of risk (coefficients) with increasing time since exposure. Miners' studies previously formed the basis for estimating risks to people exposed to radon at home, with downward extrapolation from exposures in mines to residential levels of radon. Presently, the risk estimates from residential studies are adequate to estimate radon risks in homes. Although there are major uncertainties in extrapolating the risks of exposure to radon from the miner studies to assessing risks in the home, there is remarkably good agreement between the average of risk factors derived from miner studies and those from pooled residential case-control studies. There are now over 20 analytical studies of residential radon and lung cancer. These studies typically assess the relative risk from exposure to radon based on estimates of residential exposure over a period of 25 to 30 years prior to diagnosis of lung cancer. Recent pooled analyses of residential case-control studies support a small but detectable lung cancer risk from residential exposure, and this risk increases with increasing concentrations. The excess relative risk of lung cancer from long-term residential exposure is about the same for both smokers and non-smokers; however, because the

  4. Residential radon and lung cancer in never smokers. A systematic review.

    PubMed

    Torres-Durán, María; Barros-Dios, Juan Miguel; Fernández-Villar, Alberto; Ruano-Ravina, Alberto

    2014-04-01

    Radon exposure is considered the second cause of lung cancer and the first in never smokers. We aim to assess the effect of residential radon exposure on the risk of lung cancer in never smokers through a systematic review applying predefined inclusion and exclusion criteria. 14 Studies were included. Some of them point to a relationship between residential radon and lung cancer while others show no association. Further studies are necessary to test this association and to assess if other risk factors such as environmental tobacco smoke could modify the effect of residential radon exposure on lung cancer.

  5. Radon gas: Health risks and toxicity. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1996-01-01

    The bibliography contains citations concerning health risks and toxicity associated with indoor and outdoor exposure to radon gas. Citations discuss radon sources from tobacco smoke, fossil fuel combustion, phosphate mining, uranium mining, granitic rocks, building materials, and water supplies. Discussed also are risk assessment, regulations, radon gas monitoring, exposure modeling and control, biological pathways, and occupational exposure. Radionuclides in groundwater, and radon analysis and detection, are examined in separate bibliographies. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  6. Radon gas: Health risks and toxicity. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    Not Available

    1994-01-01

    The bibliography contains citations concerning health risks and toxicity associated with indoor and outdoor exposure to radon gas. Citations discuss radon sources from tobacco smoke, fossil fuel combustion, phosphate mining, uranium mining, granitic rocks, building materials, and water supplies. Discussed also are risk assessment, regulations, radon gas monitoring, exposure modeling and control, biological pathways, and occupational exposure. Radionuclides in groundwater, and radon analysis and detection, are examined in separate bibliographies. (Contains a minimum of 130 citations and includes a subject term index and title list.)

  7. Assessment of the unattached fraction of indoor radon progeny and its contribution to dose: a pilot study in China.

    PubMed

    Guo, Qiuju; Zhang, Lei; Guo, Lu

    2012-12-01

    The unattached fraction of radon progeny (f(p)) is one of the most important factors for accurate evaluation of the effective dose from a unit of radon exposure, and it may vary greatly in different environments. For precise evaluation of the indoor radon exposure dose and the influence of unattached radon progeny, a pilot survey of f(p) in different environments was carried out in China with a portable and integrating monitor. The dose conversion factors for radon progeny are calculated with LUDEP(®) code, and the dose contributions from the unattached and the attached radon progenies were simultaneously evaluated based on the results of field measurements. The results show that even though the concentrations of radon progeny vary significantly among different indoor environments, the variations of f(p) seem relatively small (9.3-16.9%). The dose contribution from unattached radon progeny is generally larger (30.2-46.2%) in an indoor environment.

  8. RADON REDUCTION AND RADON RESISTANT CONSTRUCTION DEMONSTRATIONS IN NEW YORK

    EPA Science Inventory

    The report covers three tasks related to indoor radon: (1) the demonstration of radon reduction techniques in 8 houses in each of two uniquely different radon prone areas of the State of New York; (2) the evaluation and repair of 14 radon mitigation systems in houses mitigated 4 ...

  9. Atmosphere purification of radon and radon daughter elements

    DOEpatents

    Stein, L.

    1973-12-11

    A method for purifying an atmosphere of radon and radon daughter elements which may be contained therein by contacting the atmosphere with a fluorinating solution, whereby the radon and radon daughters are oxidized to their respective fluorides is discussed. The fluorides dissolve in the fluorinating solutlon and are removed from the atmosphere, which may then be recirculated. (Official Gazette)

  10. Variance of indoor radon concentration: Major influencing factors.

    PubMed

    Yarmoshenko, I; Vasilyev, A; Malinovsky, G; Bossew, P; Žunić, Z S; Onischenko, A; Zhukovsky, M

    2016-01-15

    Variance of radon concentration in dwelling atmosphere is analysed with regard to geogenic and anthropogenic influencing factors. Analysis includes review of 81 national and regional indoor radon surveys with varying sampling pattern, sample size and duration of measurements and detailed consideration of two regional surveys (Sverdlovsk oblast, Russia and Niška Banja, Serbia). The analysis of the geometric standard deviation revealed that main factors influencing the dispersion of indoor radon concentration over the territory are as follows: area of territory, sample size, characteristics of measurements technique, the radon geogenic potential, building construction characteristics and living habits. As shown for Sverdlovsk oblast and Niška Banja town the dispersion as quantified by GSD is reduced by restricting to certain levels of control factors. Application of the developed approach to characterization of the world population radon exposure is discussed. PMID:26409145

  11. Variance of indoor radon concentration: Major influencing factors.

    PubMed

    Yarmoshenko, I; Vasilyev, A; Malinovsky, G; Bossew, P; Žunić, Z S; Onischenko, A; Zhukovsky, M

    2016-01-15

    Variance of radon concentration in dwelling atmosphere is analysed with regard to geogenic and anthropogenic influencing factors. Analysis includes review of 81 national and regional indoor radon surveys with varying sampling pattern, sample size and duration of measurements and detailed consideration of two regional surveys (Sverdlovsk oblast, Russia and Niška Banja, Serbia). The analysis of the geometric standard deviation revealed that main factors influencing the dispersion of indoor radon concentration over the territory are as follows: area of territory, sample size, characteristics of measurements technique, the radon geogenic potential, building construction characteristics and living habits. As shown for Sverdlovsk oblast and Niška Banja town the dispersion as quantified by GSD is reduced by restricting to certain levels of control factors. Application of the developed approach to characterization of the world population radon exposure is discussed.

  12. 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.

  13. Human Lung Cancer Risks from Radon – Part III - Evidence of Influence of Combined Bystander and Adaptive Response Effects on Radon Case-Control Studies - A Microdose Analysis

    PubMed Central

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

    2012-01-01

    Since the publication of the BEIR VI (1999) report on health risks from radon, a significant amount of new data has been published showing various mechanisms that may affect the ultimate assessment of radon as a carcinogen, in particular the potentially deleterious Bystander Effect (BE) and the potentially beneficial Adaptive Response radio-protection (AR). The case-control radon lung cancer risk data of the pooled 13 European countries radon study (Darby et al 2005, 2006) and the 8 North American pooled study (Krewski et al 2005, 2006) have been evaluated. The large variation in the odds ratios of lung cancer from radon risk is reconciled, based on the large variation in geological and ecological conditions and variation in the degree of adaptive response radio-protection against the bystander effect induced lung damage. The analysis clearly shows Bystander Effect radon lung cancer induction and Adaptive Response reduction in lung cancer in some geographical regions. It is estimated that for radon levels up to about 400 Bq m−3 there is about a 30% probability that no human lung cancer risk from radon will be experienced and a 20% probability that the risk is below the zero-radon, endogenic spontaneous or perhaps even genetically inheritable lung cancer risk rate. The BEIR VI (1999) and EPA (2003) estimates of human lung cancer deaths from radon are most likely significantly excessive. The assumption of linearity of risk, by the Linear No-Threshold Model, with increasing radon exposure is invalid. PMID:22942874

  14. Radon and radon daughter levels in energy efficient housing.

    PubMed

    McGregor, R G; Walker, W B; Létourneau, E G

    1985-10-01

    Radon and radon daughter concentrations have been measured in 33 "energy-efficient" homes in a small subdivision in Kanata, Ontario. Integrated radon measurements were determined over three month periods for a year using solid state nuclear track detectors. Radon and radon daughter grab sample determinations were made during corresponding periods and confirm the distributions of the integrated radon measurements. Annual average individual home radon concentrations show an 8 fold concentration range between homes. This variability in radon concentrations is not reflected in the range of air exchange rates for the homes. A distinct seasonal variation is noted for the median values of the radon and radon daughter concentrations and the equilibrium factor F in the dwellings.

  15. The reliability of radon as seismic precursor

    NASA Astrophysics Data System (ADS)

    Emilian Toader, Victorin; Moldovan, Iren Adelina; Ionescu, Constantin; Marmureanu, Alexandru

    2016-04-01

    Our multidisciplinary network (AeroSolSys) located in Vrancea (Curvature Carpathian Mountains) includes radon concentration monitoring in five stations. We focus on lithosphere and near surface low atmosphere phenomena using real-time information about seismicity, + / - ions, clouds, solar radiation, temperature (air, ground), humidity, atmospheric pressure, wind speed and direction, telluric currents, variations of the local magnetic field, infrasound, variations of the atmospheric electrostatic field, variations in the earth crust with inclinometers, electromagnetic activity, CO2 concentration, ULF radio wave propagation, seismo-acoustic emission, animal behavior. The main purpose is to inform the authorities about risk situation and update hazard scenarios. The radon concentration monitoring is continuously with 1 hour or 3 hours sample rate in locations near to faults in an active seismic zone characterized by intermediate depth earthquakes. Trigger algorithms include standard deviation, mean and derivative methods. We correlate radon concentration measurements with humidity, temperature and atmospheric pressure from the same equipment. In few stations we have meteorological information, too. Sometime the radon concentration has very high variations (maxim 4535 Bq/m3 from 106 Bq/m3) in short time (1 - 2 days) without being accompanied by an important earthquake. Generally the cause is the high humidity that could be generated by tectonic stress. Correlation with seismicity needs information from minimum 6 month in our case. For 10605 hours, 618 earthquakes with maxim magnitude 4.9 R, we have got radon average 38 Bq/m3 and exposure 408111 Bqh/m3 in one station. In two cases we have correlation between seismicity and radon concentration. In other one we recorded high variation because the location was in an area with multiple faults and a river. Radon can be a seismic precursor but only in a multidisciplinary network. The anomalies for short or long period of

  16. LARGE BUILDING RADON MANUAL

    EPA Science Inventory

    The report summarizes information on how bilding systems -- especially the heating, ventilating, and air-conditioning (HVAC) system -- inclurence radon entry into large buildings and can be used to mitigate radon problems. It addresses the fundamentals of large building HVAC syst...

  17. An updated review of case-control studies of lung cancer and indoor radon-Is indoor radon the risk factor for lung cancer?

    PubMed

    Sheen, Seungsoo; Lee, Keu Sung; Chung, Wou Young; Nam, Saeil; Kang, Dae Ryong

    2016-01-01

    Lung cancer is a leading cause of cancer-related death in the world. Smoking is definitely the most important risk factor for lung cancer. Radon ((222)Rn) is a natural gas produced from radium ((226)Ra) in the decay series of uranium ((238)U). Radon exposure is the second most common cause of lung cancer and the first risk factor for lung cancer in never-smokers. Case-control studies have provided epidemiological evidence of the causative relationship between indoor radon exposure and lung cancer. Twenty-four case-control study papers were found by our search strategy from the PubMed database. Among them, seven studies showed that indoor radon has a statistically significant association with lung cancer. The studies performed in radon-prone areas showed a more positive association between radon and lung cancer. Reviewed papers had inconsistent results on the dose-response relationship between indoor radon and lung cancer risk. Further refined case-control studies will be required to evaluate the relationship between radon and lung cancer. Sufficient study sample size, proper interview methods, valid and precise indoor radon measurement, wide range of indoor radon, and appropriate control of confounders such as smoking status should be considered in further case-control studies.

  18. An updated review of case-control studies of lung cancer and indoor radon-Is indoor radon the risk factor for lung cancer?

    PubMed

    Sheen, Seungsoo; Lee, Keu Sung; Chung, Wou Young; Nam, Saeil; Kang, Dae Ryong

    2016-01-01

    Lung cancer is a leading cause of cancer-related death in the world. Smoking is definitely the most important risk factor for lung cancer. Radon ((222)Rn) is a natural gas produced from radium ((226)Ra) in the decay series of uranium ((238)U). Radon exposure is the second most common cause of lung cancer and the first risk factor for lung cancer in never-smokers. Case-control studies have provided epidemiological evidence of the causative relationship between indoor radon exposure and lung cancer. Twenty-four case-control study papers were found by our search strategy from the PubMed database. Among them, seven studies showed that indoor radon has a statistically significant association with lung cancer. The studies performed in radon-prone areas showed a more positive association between radon and lung cancer. Reviewed papers had inconsistent results on the dose-response relationship between indoor radon and lung cancer risk. Further refined case-control studies will be required to evaluate the relationship between radon and lung cancer. Sufficient study sample size, proper interview methods, valid and precise indoor radon measurement, wide range of indoor radon, and appropriate control of confounders such as smoking status should be considered in further case-control studies. PMID:26949535

  19. Real-time setup to record radon emission during rock deformation: implications for geochemical surveillance

    NASA Astrophysics Data System (ADS)

    Tuccimei, P.; Mollo, S.; Soligo, M.; Scarlato, P.; Castelluccio, M.

    2015-02-01

    Laboratory experiments can represent a valid approach to unravel the complex interplay between the geochemical behaviour of radon and rock deformation mechanisms. In light of this, we present a new real-time experimental setup for analyzing in continuum the alpha-emitting 222Rn and 220Rn daughters over variable stress-strain regimes. The most innovative segment of this setup consists of the radon accumulation chamber obtained from a tough and durable material that can host large cylindrical rock samples. The accumulation chamber is connected, in a closed-loop configuration, to a gas-drying unit and to a RAD7 radon monitor. A re-circulating pump moves the gas from the rock sample to a solid-state detector for alpha counting of radon and thoron progeny. The measured radon signal is enhanced by surrounding the accumulation chamber with a digitally controlled heating belt. As the temperature is increased, the number of effective collision of radon atoms increases favouring the diffusion of radon through the material and reducing the analytical uncertainty. The accumulation chamber containing the sample is then placed into an uniaxial testing apparatus where the axial deformation is measured throughout a linear variable displacement transducer. A dedicated software allows to obtain a variety of stress-strain regimes from fast deformation rates to long-term creep tests. Experiments conducted with this new real-time setup have important ramifications for the interpretation of geochemical anomalies recorded prior to volcanic eruptions or earthquakes.

  20. Real-time setup to measure radon emission during rock deformation: implications for geochemical surveillance

    NASA Astrophysics Data System (ADS)

    Tuccimei, P.; Mollo, S.; Soligo, M.; Scarlato, P.; Castelluccio, M.

    2015-05-01

    Laboratory experiments can represent a valid approach to unravel the complex interplay between the geochemical behaviour of radon and rock deformation mechanisms. In light of this, we present a new real-time experimental setup for analysing in continuum the alpha-emitting 222Rn and 220Rn daughters over variable stress-strain regimes. The most innovative segment of this setup consists of the radon accumulation chamber obtained from a tough and durable material that can host large cylindrical rock samples. The accumulation chamber is connected, in a closed-loop configuration, to a gas-drying unit and to a RAD7 radon monitor. A recirculating pump moves the gas from the rock sample to a solid-state detector for alpha counting of radon and thoron progeny. The measured radon signal is enhanced by surrounding the accumulation chamber with a digitally controlled heating belt. As the temperature is increased, the number of effective collisions of radon atoms increases favouring the diffusion of radon through the material and reducing the analytical uncertainty. The accumulation chamber containing the sample is then placed into a uniaxial testing apparatus where the axial deformation is measured throughout a linear variable displacement transducer. A dedicated software allows obtaining a variety of stress-strain regimes from fast deformation rates to long-term creep tests. Experiments conducted with this new real-time setup have important ramifications for the interpretation of geochemical anomalies recorded prior to volcanic eruptions or earthquakes.

  1. Comparison of secondary organic aerosol formed with an aerosol flow reactor and environmental reaction chambers: effect of oxidant concentration, exposure time and seed particles on chemical composition and yield

    DOE PAGES

    Lambe, A. T.; Chhabra, P. S.; Onasch, T. B.; Brune, W. H.; Hunter, J. F.; Kroll, J. H.; Cummings, M. J.; Brogan, J. F.; Parmar, Y.; Worsnop, D. R.; et al

    2014-12-02

    We performed a systematic intercomparison study of the chemistry and yields of SOA generated from OH oxidation of a common set of gas-phase precursors in a Potential Aerosol Mass (PAM) continuous flow reactor and several environmental chambers. In the flow reactor, SOA precursors were oxidized using OH concentrations ranging from 2.0×108 to 2.2×1010 molec cm-3 over exposure times of 100 s. In the environmental chambers, precursors were oxidized using OH concentrations ranging from 2×106 to 2×107 molec cm-3 over exposure times of several hours. The OH concentration in the chamber experiments is close to that found in the atmosphere, butmore » the integrated OH exposure in the flow reactor can simulate atmospheric exposure times of multiple days compared to chamber exposure times of only a day or so. A linear correlation analysis of the mass spectra (m=0.91–0.92, r2=0.93–0.94) and carbon oxidation state (m=1.1, r2=0.58) of SOA produced in the flow reactor and environmental chambers for OH exposures of approximately 1011 molec cm-3 s suggests that the composition of SOA produced in the flow reactor and chambers is the same within experimental accuracy as measured with an aerosol mass spectrometer. This similarity in turn suggests that both in the flow reactor and in chambers, SOA chemical composition at low OH exposure is governed primarily by gas-phase OH oxidation of the precursors, rather than heterogeneous oxidation of the condensed particles. In general, SOA yields measured in the flow reactor are lower than measured in chambers for the range of equivalent OH exposures that can be measured in both the flow reactor and chambers. The influence of sulfate seed particles on isoprene SOA yield measurements was examined in the flow reactor. The studies show that seed particles increase the yield of SOA produced in flow reactors by a factor of 3 to 5 and may also account in part for higher SOA yields obtained in the chambers, where seed particles are

  2. Chemical properties of radon

    SciTech Connect

    Stein, L.

    1986-01-01

    Radon is frequently regarded as a totally inert element. It is, however, a ''metalloid'' - an element which lies on the diagonal of the Periodic Table between the true metals and nonmetals and which exhibits some of the characteristics of both. It reacts with fluorine, halogen fluorides, dioxygenyl salts, fluoro-nitrogen salts, and halogen fluoride-metal fluoride complexes to form ionic compounds. Several of the solid reagents can be used to collect radon from air but must be protected from moisture, since they hydrolyze readily. Recently, solutions of nonvolatile, cationic radon have been produced in nonaqueous solvents. Ion-exchange studies have shown that the radon can be quantitatively collected on columns packed with either Nafion resins or complex salts. In its ionic state, radon is able to displace H/sup +/, Na/sup +/, K/sup +/, Cs/sup +/, Ca/sup 2 +/, and Ba/sup 2 +/ ions from a number of solid materials. 27 refs., 6 figs.

  3. Rating radon through the looking glass

    SciTech Connect

    Not Available

    1993-05-03

    Radon emerged as a health threat in the last five years as studies showed that exposure to high levels in the home can cause lung cancer. But many families move so often that its difficult to determine their exposure over a lifetime. Now, Battelle Memorial Institute scientists at the Energy Dept.'s Pacific Northwest Lab in Richland, Wash., have devised a clever way to do so. They tape a 2-inch-square piece of clear plastic polymer to the glass on an old mirror or framed picture. Such items as wedding photos are easily datable and normally carried from home to home. As radon decays over the years, it emits alpha particles, which embed themselves in glass. The particles leave tracks in the polymer. By analyzing these tracks, scientists can estimate a person's average annual exposure to indoor radon over 20 years or more. Starting in May, the technique will be used in a three-year National Cancer Institute study that examines radon, smoking, and diet as co-factors in the risk of lung cancer.

  4. 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. PMID:16410290

  5. Assessment of the multimedia mitigation of radon in New York.

    PubMed

    Kitto, Michael E

    2007-05-01

    Although not yet implemented, the 1996 amendments to the Safe Drinking Water Act instructed the states (or local water suppliers) to address radon concentrations in community water systems (CWS). As an alternative to reducing waterborne radon concentrations in the CWS to the maximum contaminant level (MCL) of 11 Bq L(-1), states (or individual CWS) would be permitted to develop a multimedia mitigation (MMM) program, which allowed a greater concentration (148 Bq L(-1)) of waterborne radon in the CWS, if it could be shown that an equivalent health risk reduction could be achieved by reducing indoor radon concentrations. For a MMM program to be acceptable, the U.S. Environmental Protection Agency required the health-risk reduction attained through mitigations and radon-resistant new construction (RRNC) to offset the increased health risk due to radon in community water systems above the MCL of 11 Bq L(-1). A quantitative assessment indicates that the reduction in health risk currently achieved in New York State through radon mitigations and RRNC exceeded the increase in risk associated with an alternative MCL of 148 Bq L(-1). The implementation of a MMM program in New York would result in an overall reduction in the health risk associated with exposure to radon. PMID:17429303

  6. Occupational exposure to radon and natural gamma radiation in the La Carolina, a former gold mine in San Luis Province, Argentina.

    PubMed

    Anjos, R M; Umisedo, N; da Silva, A A R; Estellita, L; Rizzotto, M; Yoshimura, E M; Velasco, H; Santos, A M A

    2010-02-01

    Radon and gamma radiation level measurements were carried out inside the La Carolina mine, one of the oldest gold mining camps of southern South America, which is open for touristic visits nowadays. CR-39 track-etch detectors and thermoluminescent dosimeters of natural CaF(2) and LiF TLD-100 were exposed at 14 points along the mine tunnels in order to estimate the mean (222)Rn concentration and the ambient dose equivalent during the summer season (November 2008 to February 2009). The values for the (222)Rn concentration at each monitoring site ranged from 1.8+/-0.1 kBqm(-3) to 6.0+/-0.5 kBqm(-3), with a mean value of 4.8 kBqm(-3), indicating that these measurements exceed in about three times the upper action level recommended by ICRP for workplaces. The correlations between radon and gamma radiation levels inside the mine were also investigated. Effective doses due to (222)Rn and gamma rays inside the mine were determined, resulting in negligible values to tourists. Considering the effective dose to the mine tourist guides, values exceeding 20mSv of internal contribution to the effective doses can be reached, depending on the number of working hours inside the mine.

  7. 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. PMID:26065929

  8. Procedure for the characterization of radon potential in existing dwellings and to assess the annual average indoor radon concentration.

    PubMed

    Collignan, Bernard; Powaga, Emilie

    2014-11-01

    Risk assessment due to radon exposure indoors is based on annual average indoor radon activity concentration. To assess the radon exposure in a building, measurement is generally performed during at least two months during heating period in order to be representative of the annual average value. This is because radon presence indoors could be very variable during time. This measurement protocol is fairly reliable but may be a limiting in the radon risk management, particularly during a real estate transaction due to the duration of the measurement and the limitation of the measurement period. A previous field study defined a rapid methodology to characterize radon entry in dwellings. The objective of this study was at first, to test this methodology in various dwellings to assess its relevance with a daily test. At second, a ventilation model was used to assess numerically the air renewal of a building, the indoor air quality all along the year and the annual average indoor radon activity concentration, based on local meteorological conditions, some building characteristics and in-situ characterization of indoor pollutant emission laws. Experimental results obtained on thirteen individual dwellings showed that it is generally possible to obtain a representative characterization of radon entry into homes. It was also possible to refine the methodology defined in the previous study. In addition, numerical assessments of annual average indoor radon activity concentration showed generally a good agreement with measured values. These results are encouraging to allow a procedure with a short measurement time to be used to characterize long-term radon potential in dwellings. PMID:25011073

  9. Procedure for the characterization of radon potential in existing dwellings and to assess the annual average indoor radon concentration.

    PubMed

    Collignan, Bernard; Powaga, Emilie

    2014-11-01

    Risk assessment due to radon exposure indoors is based on annual average indoor radon activity concentration. To assess the radon exposure in a building, measurement is generally performed during at least two months during heating period in order to be representative of the annual average value. This is because radon presence indoors could be very variable during time. This measurement protocol is fairly reliable but may be a limiting in the radon risk management, particularly during a real estate transaction due to the duration of the measurement and the limitation of the measurement period. A previous field study defined a rapid methodology to characterize radon entry in dwellings. The objective of this study was at first, to test this methodology in various dwellings to assess its relevance with a daily test. At second, a ventilation model was used to assess numerically the air renewal of a building, the indoor air quality all along the year and the annual average indoor radon activity concentration, based on local meteorological conditions, some building characteristics and in-situ characterization of indoor pollutant emission laws. Experimental results obtained on thirteen individual dwellings showed that it is generally possible to obtain a representative characterization of radon entry into homes. It was also possible to refine the methodology defined in the previous study. In addition, numerical assessments of annual average indoor radon activity concentration showed generally a good agreement with measured values. These results are encouraging to allow a procedure with a short measurement time to be used to characterize long-term radon potential in dwellings.

  10. Measurement of radon concentration in some water samples belonging to some adjoining areas of Pathankot, Punjab

    NASA Astrophysics Data System (ADS)

    Kumar, Ajay; Sharma, Sumit

    2015-08-01

    The study of radon concentration was measured in some areas of Pathankot district, Punjab, India, from the health hazard point of view due to radon. The exposure to radon through drinking water is largely by inhalation and ingestion. RAD 7, an electronic solid state silicon detector (Durridgeco., USA) was used to measure the radon concentration in drinking water samples of the study area. The recorded values of radon concentration in these water samples are below the recommended limit by UNSCEAR and European commission. The recommended limit of radon concentration in water samples is 4 to 40 Bq/l given by UNSCEAR [1] and European commission has recommended the safe limit for radon concentration in water sample is 100 Bq/l [2].

  11. Radon Levels in Nurseries and Primary Schools in Bragança District-Preliminary Assessment.

    PubMed

    Sousa, S I V; Branco, P T B S; Nunes, R A O; Alvim-Ferraz, M C M; Martins, F G

    2015-01-01

    Lung cancer has been associated with radon concentration even at low levels such as those found in dwellings. This study aimed to (i) determine radon diurnal variations in three nurseries and one primary school in the Bragança district (north of Portugal) and (ii) compare radon concentrations with legislated standards and assess the legislated procedures. Radon was measured in three nurseries and a primary school in a rural area with nongranite soil. Measurements were performed continuously to examine differences between occupation and nonoccupation periods. Indoor temperature and relative humidity were also measured continuously. A great variability was found in radon concentrations between the microenvironments examined. Radon concentrations surpassed by severalfold the recommended guidelines and thresholds, and excessive levels of health concern were sporadically found (361.5-753.5 Bq m(-3)). Thus, it is of importance to perform a national campaign on radon measurements and to reduce exposure. PMID:26167747

  12. Measurement of radon concentration in some water samples belonging to some adjoining areas of Pathankot, Punjab

    SciTech Connect

    Kumar, Ajay Sharma, Sumit

    2015-08-28

    The study of radon concentration was measured in some areas of Pathankot district, Punjab, India, from the health hazard point of view due to radon. The exposure to radon through drinking water is largely by inhalation and ingestion. RAD 7, an electronic solid state silicon detector (Durridgeco., USA) was used to measure the radon concentration in drinking water samples of the study area. The recorded values of radon concentration in these water samples are below the recommended limit by UNSCEAR and European commission. The recommended limit of radon concentration in water samples is 4 to 40 Bq/l given by UNSCEAR [1] and European commission has recommended the safe limit for radon concentration in water sample is 100 Bq/l [2].

  13. Radon Levels in Nurseries and Primary Schools in Bragança District-Preliminary Assessment.

    PubMed

    Sousa, S I V; Branco, P T B S; Nunes, R A O; Alvim-Ferraz, M C M; Martins, F G

    2015-01-01

    Lung cancer has been associated with radon concentration even at low levels such as those found in dwellings. This study aimed to (i) determine radon diurnal variations in three nurseries and one primary school in the Bragança district (north of Portugal) and (ii) compare radon concentrations with legislated standards and assess the legislated procedures. Radon was measured in three nurseries and a primary school in a rural area with nongranite soil. Measurements were performed continuously to examine differences between occupation and nonoccupation periods. Indoor temperature and relative humidity were also measured continuously. A great variability was found in radon concentrations between the microenvironments examined. Radon concentrations surpassed by severalfold the recommended guidelines and thresholds, and excessive levels of health concern were sporadically found (361.5-753.5 Bq m(-3)). Thus, it is of importance to perform a national campaign on radon measurements and to reduce exposure.

  14. 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.

  15. Response of potato to discontinuous exposures of atmospheric ethylene: results of a long-term experiment in open-top chambers and crop growth modelling

    NASA Astrophysics Data System (ADS)

    Dueck, Th. A.; Van Dijk, C. J.; Grashoff, C.; Groenwold, J.; Schapendonk, A. H. C. M.; Tonneijck, A. E. G.

    A field experiment in open-top chambers (OTCs) was performed to quantitatively assess the growth and yield response of potato to discontinuous exposures to atmospheric ethylene (200, 400 and 800 ppb, applied twice weekly and 200 and 400 ppb applied 4 times weekly, each for 3 h/event). To evaluate the effect of ethylene on potato tuber yield, a module was developed for an existing crop growth simulation model by incorporating the effects of ethylene on epinasty and photosynthesis. Explorations with the model showed that in a worst case scenario, ethylene-induced epinasty had only a marginal effect on tuber yield. Short-term exposures to ethylene under laboratory conditions inhibited photosynthesis, but it recovered within 48 h. When exposed to ethylene for longer than 12 h, irreversible damage of the photosynthesis apparatus occurred. Exposure to ethylene in the OTCs resulted in epinasty and reduced flowering. The number of flowers on potato decreased with increasing concentrations of ethylene, irrespective of the exposure frequency. Calculations showed that the number of flowers was significantly reduced at ca. 170 ppb ethylene, averaged over the hours of exposure. Ethylene concentrations up to 800 ppb, administered 4 times weekly for 3 h during the growing season, did not affect vegetative growth and yield in fumigated potatoes. Under these experimental conditions, the modified simulation model incorporating the effects of ethylene on epinasty and photosynthesis forecasts a 5% effect on tuber yield at concentrations of 1600 ppb. All results indicate that ethylene concentrations higher than 800 ppb are required to adversely affect tuber yield of potato.

  16. Experimental animal studies of radon and cigarette smoke

    SciTech Connect

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

    1992-12-31

    Cigarette-smoking is a dominant cause of lung cancer and confounds risk assessment of exposure to radon decay products. Evidence in humans on the interaction between cigarette-smoking and exposure to radon decay products, although limited, indicates a possible synergy. Experimental animal data, in addition to showing synergy, also show a decrease or no change in risk with added cigarette-smoke exposures. This article reviews previous animal data developed at Compagnie Generale des Matieres Nucleaires and Pacific Northwest Laboratory (PNL) on mixed exposures to radon and cigarette smoke, and highlights new initiation-promotion-initiation (IPI) studies at PNL that were designed within the framework of a two-mutation carcinogenesis model. Also presented are the PNL exposure system, experimental protocols, dosimetry, and biological data observed to date in IPI animals.

  17. Radon and lung cancer risk: taking stock at the millenium.

    PubMed Central

    Samet, J M; Eradze, G R

    2000-01-01

    Radon is a well-established human carcinogen for which extensive data are available, extending into the range of exposures experienced by the general population. Mounting epidemiologic evidence on radon and lung cancer risk, now available from more than 20 different studies of underground miners and complementary laboratory findings, indicates that risks are linear in exposure without threshold. Radon is also a ubiquitous indoor air pollutant in homes, and risk projections imply that radon is the second leading cause of lung cancer after smoking. Recommended control strategies in the United States and other countries, which include testing of most homes and mitigation of those exceeding guideline levels, have been controversial. Further research is needed, drawing on molecular and cellular approaches and continuing the follow-up of the underground miner cohorts, and scientists should work toward constructing mechanistically based models that combine epidemiologic and experimental data to yield risk estimates with enhanced certainty. Images Figure 1 Figure 2 PMID:10931781

  18. Use of threshold-specific energy model for the prediction of effects of smoking and radon exposure on the risk of lung cancer.

    PubMed

    Böhm, R; Sedlák, A; Bulko, M; Holý, K

    2014-07-01

    Lung cancer is the leading cause of cancer death in both men and women. Smoking causes 80-90% of cases of lung cancer. In this study, an attempt was made to assess the impact of cigarette smoking on the risk of lung cancer by the so-called threshold-specific energy model. This model allows to analyse the biological effects of radon daughter products on the lung tissue, and is based on the assumption that the biological effect (i.e. cell inactivation) will manifest itself after the threshold-specific energy z0 deposited in the sensitive volume of the cell is exceeded. Cigarette smoking causes, among others, an increase in the synthesis of the survivin protein that protects cells from apoptosis and thereby reduces their radiosensitivity. Based on these facts, an attempt was made to estimate the shape of the curves describing the increase in the oncological effect of radiation as a function of daily cigarette consumption.

  19. Use of threshold-specific energy model for the prediction of effects of smoking and radon exposure on the risk of lung cancer.

    PubMed

    Böhm, R; Sedlák, A; Bulko, M; Holý, K

    2014-07-01

    Lung cancer is the leading cause of cancer death in both men and women. Smoking causes 80-90% of cases of lung cancer. In this study, an attempt was made to assess the impact of cigarette smoking on the risk of lung cancer by the so-called threshold-specific energy model. This model allows to analyse the biological effects of radon daughter products on the lung tissue, and is based on the assumption that the biological effect (i.e. cell inactivation) will manifest itself after the threshold-specific energy z0 deposited in the sensitive volume of the cell is exceeded. Cigarette smoking causes, among others, an increase in the synthesis of the survivin protein that protects cells from apoptosis and thereby reduces their radiosensitivity. Based on these facts, an attempt was made to estimate the shape of the curves describing the increase in the oncological effect of radiation as a function of daily cigarette consumption. PMID:24711526

  20. Radon reduction and radon monitoring in the NEMO experiment

    SciTech Connect

    Nachab, A.

    2007-03-28

    The first data of the NEMO 3 neutrinoless double beta decay experiment have shown that the radon can be a non negligible component of the background. In order to reduce the radon level in the gas mixture, it has been necessary first to cover the NEMO 3 detector with an airtight tent and then to install a radon-free air factory. With the use of sensitive radon detectors, the level of radon at the exit of the factory and inside the tent is continuously controlled. These radon levels are discussed within the NEMO 3 context.

  1. A mathematical approach for predicting long-term indoor radon concentrations from short-term measurements

    SciTech Connect

    Al-Ahmady, K.K.; Hintenlang, D.E.

    1995-12-31

    Assessment of long-term radon concentrations from short-term testing results are of significant importance when radon risk assessment and liability issues are considered. These issues are based on the figure of annual exposure to indoor radon while radon measurement practices are mainly followed the EPA short-term testing protocols. A mathematical framework has been developed that facilities non-statistical approach to construct the relationship between the short-term indoor radon measurements and the long term annual indoor radon levels. This approach was based on the application of the time-dependent indoor radon concentrations calculated from the corresponding contributions of indoor radon driving forces for different time periods having a reference starting time. The approach utilizes an analytical procedure that is based on the solutions of the mass balance equation for the radon gas in the indoor environment. The solutions are applied through semi-analytical modeling of time-dependent indoor radon concentrations. This treatment provides a powerful tool and procedure to assess long-term indoor radon concentrations from short-term testing results.

  2. Residents in a high radon potential geographic area: Their risk perception and attitude toward testing and mitigation

    SciTech Connect

    Ferng, S.F.; Lawson, J.K.

    1996-01-01

    Boone County, Indiana was identified by the EPA as one of the high radon potential geographic areas. Health education campaigns are needed to prevent resident`s unnecessary radon exposure. In order to design suitable programs, a questionnaire mail survey was conducted to measure socio-demographic characteristics of County resident`s knowledge about radon, attitude toward radon testing and mitigation, support of education campaigns, and the best media to deliver radon education campaigns. A stratified random sampling method was applied for a total of 400 samples. The number of samples from each township/city was a proportion of their taxable parcels. The survey return rate was 39.8%. The data were analyzed by Epi Info and SPSS. The statistical significant level was set at {alpha} = 0.05. The results showed that resident`s knowledge about radon was at a relatively superficial level. There was no association identified between the knowledge of radon and gender, age, family income, or education, except that females more frequently believed in false effects caused by radon. A significant correlation between radon knowledge and home radon tests was observed. Also found in this study was that respondents with better knowledge about diseases caused by radon had more confidence in radon mitigation actions. Newspaper was chosen by respondents as the most favorite media to deliver radon health education campaigns. Health education campaigns for the residents of Boone County might be conducted by local governments and/or other organizations.

  3. Radon releases from Australian uranium mining and milling projects: assessing the UNSCEAR approach.

    PubMed

    Mudd, Gavin M

    2008-02-01

    The release of radon gas and progeny from the mining and milling of uranium-bearing ores has long been recognised as a potential radiological health hazard. The standards for exposure to radon and progeny have decreased over time as the understanding of their health risk has improved. In recent years there has been debate on the long-term releases (10,000 years) of radon from uranium mining and milling sites, focusing on abandoned, operational and rehabilitated sites. The primary purpose has been estimates of the radiation exposure of both local and global populations. Although there has been an increasing number of radon release studies over recent years in the USA, Australia, Canada and elsewhere, a systematic evaluation of this work has yet to be published in the international literature. This paper presents a detailed compilation and analysis of Australian studies. In order to quantify radon sources, a review of data on uranium mining and milling wastes in Australia, as they influence radon releases, is presented. An extensive compilation of the available radon release data is then assembled for the various projects, including a comparison to predictions of radon behaviour where available. An analysis of cumulative radon releases is then developed and compared to the UNSCEAR approach. The implications for the various assessments of long-term releases of radon are discussed, including aspects such as the need for ongoing monitoring of rehabilitation at uranium mining and milling sites and life-cycle accounting.

  4. Po-210 as long-term integrating radon indicator in the indoor environment

    SciTech Connect

    Samuelsson, C.

    1990-07-01

    The general objective is to improve the knowledge about the transferring processes leading from airborne radon/radon daughters to embedded Po-210 in hard surfaces in the indoor environment. The specific goal of the research is to identify situations in which the surface activity of Po-210 can be used as a long-term indicator of lung cancer risk from past or future radon exposures.

  5. Indoor Radon Measurement in Van

    NASA Astrophysics Data System (ADS)

    Kam, E.; Osmanlioglu, A. E.; Dogan, I.; Celebi, N.

    2007-04-01

    In this study, indoor radon concentrations obtained from the radon surveys conducted in the Van. Radon monitoring was performed by applying a passive, time-integrating measuring technique. For this purpose, CR-39 nuclear track detectors were installed in dwellings for 2 months. After the monitoring period, detectors were collected. In order to make the alpha tracks visible, chemical etching was applied to the exposed detectors. Nuclear track numbers and the corresponding indoor radon concentrations were determined. Annual effective dose equivalents and the risk probabilities caused by indoor radon inhalation were calculated, and the found results compared with the indoor radon concentrations' data measured in different provinces of Turkey.

  6. Indoor Radon Measurement in Van

    SciTech Connect

    Kam, E.; Osmanlioglu, A. E.; Celebi, N.; Dogan, I.

    2007-04-23

    In this study, indoor radon concentrations obtained from the radon surveys conducted in the Van. Radon monitoring was performed by applying a passive, time-integrating measuring technique. For this purpose, CR-39 nuclear track detectors were installed in dwellings for 2 months. After the monitoring period, detectors were collected. In order to make the alpha tracks visible, chemical etching was applied to the exposed detectors. Nuclear track numbers and the corresponding indoor radon concentrations were determined. Annual effective dose equivalents and the risk probabilities caused by indoor radon inhalation were calculated, and the found results compared with the indoor radon concentrations' data measured in different provinces of Turkey.

  7. Wind-induced contaminant transport in near-surface soils with application to radon entry into buildings

    SciTech Connect

    Riley, W J

    1996-05-01

    Indoor air exposures to gaseous contaminants originating in soil can cause large human health risks. To predict and control these exposures, the mechanisms that affect vapor transport in near-surface soils need to be understood. In particular, radon exposure is a concern since average indoor radon concentrations lead to much higher risks than are generally accepted for exposure to other environmental contaminants. This dissertation examines an important component of the indoor radon problem: the impacts of wind on soil-gas and radon transport and entry into buildings. The research includes experimental and modeling studies of wind`s interactions with a building`s superstructure and the resulting soil-gas and radon flows in the surrounding soil. In addition to exploring the effects of steady winds, a novel modeling technique is developed to examine the impacts of fluctuating winds on soil-gas and radon transport.

  8. Whole-body new-born and young rats' exposure assessment in a reverberating chamber operating at 2.4 GHz

    NASA Astrophysics Data System (ADS)

    Wu, Tongning; Hadjem, Abdelhamid; Wong, Man-Fai; Gati, Azzedine; Picon, Odile; Wiart, Joe

    2010-03-01

    This paper presents the whole-body specific absorption rate (WBSAR) assessment of embryos and new-born rats' exposure in a reverberating chamber (RC) operating at 2.4 GHz (WiFi). The finite difference in time domain (FDTD) method often used in bio-electromagnetism is facing very slow convergence. A new simulation-measurement hybrid approach has been proposed to characterize the incident power related to the RC and the WBSAR in rats, which are linked by the mean squared electric field strength in the working volume. Peak localized SAR in the rat under exposure is not included in the content of the study. Detailed parameters of this approach are determined by simulations. Evolutions for the physical and physiological parameters of the small rats at different ages are discussed. Simulations have been made to analyse all the variability factors contributing to the global results. WBSAR information and the variability for rats at different ages are also discussed in the paper.

  9. Whole-body new-born and young rats' exposure assessment in a reverberating chamber operating at 2.4 GHz.

    PubMed

    Wu, Tongning; Hadjem, Abdelhamid; Wong, Man-Fai; Gati, Azzedine; Picon, Odile; Wiart, Joe

    2010-03-21

    This paper presents the whole-body specific absorption rate (WBSAR) assessment of embryos and new-born rats' exposure in a reverberating chamber (RC) operating at 2.4 GHz (WiFi). The finite difference in time domain (FDTD) method often used in bio-electromagnetism is facing very slow convergence. A new simulation-measurement hybrid approach has been proposed to characterize the incident power related to the RC and the WBSAR in rats, which are linked by the mean squared electric field strength in the working volume. Peak localized SAR in the rat under exposure is not included in the content of the study. Detailed parameters of this approach are determined by simulations. Evolutions for the physical and physiological parameters of the small rats at different ages are discussed. Simulations have been made to analyse all the variability factors contributing to the global results. WBSAR information and the variability for rats at different ages are also discussed in the paper. PMID:20182003

  10. Surface-deposition and distribution of the radon-decay products indoors.

    PubMed

    Espinosa, G; Tommasino, L

    2015-05-01

    The exposure to radon-decay products is of great concern both in dwellings and workplaces. The model to estimate the lung dose refers to the deposition mechanisms and particle sizes. Unfortunately, most of the dose data available are based on the measurement of radon concentration and the concentration of radon decay products. These combined measurements are widely used in spite of the fact that accurate dose assessments require information on the particle deposition mechanisms and the spatial distribution of radon decay products indoors. Most of the airborne particles and/or radon decay products are deposited onto indoor surfaces, which deposition makes the radon decay products unavailable for inhalation. These deposition processes, if properly known, could be successfully exploited to reduce the exposure to radon decay products. In spite of the importance of the surface deposition of the radon decay products, both for the correct evaluation of the dose and for reducing the exposure; little or no efforts have been made to investigate these deposition processes. Recently, two parallel investigations have been carried out in Rome and at Universidad Nacional Autónoma de México (UNAM) in Mexico City respectively, which address the issue of the surface-deposited radon decay products. Even though these investigations have been carried independently, they complement one another. It is with these considerations in mind that it was decided to report both investigations in the same paper. PMID:25748340

  11. Surface-deposition and Distribution of the Radon (222Rn and 220Rn) Decay Products Indoors

    NASA Astrophysics Data System (ADS)

    Espinosa, G.; Tommasino, Luigi

    The exposure to radon (222Rn and 220Rn) decay products is of great concern both in dwellings and workplaces. The model to estimate the lung dose refers to the deposition mechanisms and particle sizes. Unfortunately, most of the dose data available are based on the measurement of radon concentration and the concentration of radon decay products. These combined measurements are widely used in spite of the fact that accurate dose assessments require information on the particle deposition mechanisms and the spatial distribution of radon decay products indoors. Most of the airborne particles and/or radon decay products are deposited onto indoor surfaces, which deposition makes the radon decay products unavailable for inhalation. These deposition processes, if properly known, could be successfully exploited to reduce the exposure to radon decay products. In spite of the importance of the surface deposition of the radon decay products, both for the correct evaluation of the dose and for reducing the exposure, little or no efforts have been made to investigate these deposition processes. Recently, two parallel investigations have been carried out in Rome and at Universidad Nacional Autónoma de México (UNAM) in Mexico City respectively, which address the issue of the surface-deposited radon decay products. Even though these investigations have been carried independently, they complement one another. It is with these considerations in mind that it was decided to report both investigations in the same paper.

  12. Surface-deposition and distribution of the radon-decay products indoors.

    PubMed

    Espinosa, G; Tommasino, L

    2015-05-01

    The exposure to radon-decay products is of great concern both in dwellings and workplaces. The model to estimate the lung dose refers to the deposition mechanisms and particle sizes. Unfortunately, most of the dose data available are based on the measurement of radon concentration and the concentration of radon decay products. These combined measurements are widely used in spite of the fact that accurate dose assessments require information on the particle deposition mechanisms and the spatial distribution of radon decay products indoors. Most of the airborne particles and/or radon decay products are deposited onto indoor surfaces, which deposition makes the radon decay products unavailable for inhalation. These deposition processes, if properly known, could be successfully exploited to reduce the exposure to radon decay products. In spite of the importance of the surface deposition of the radon decay products, both for the correct evaluation of the dose and for reducing the exposure; little or no efforts have been made to investigate these deposition processes. Recently, two parallel investigations have been carried out in Rome and at Universidad Nacional Autónoma de México (UNAM) in Mexico City respectively, which address the issue of the surface-deposited radon decay products. Even though these investigations have been carried independently, they complement one another. It is with these considerations in mind that it was decided to report both investigations in the same paper.

  13. Mitigation of radon and thoron decay products by filtration.

    PubMed

    Wang, Jin; Meisenberg, Oliver; Chen, Yongheng; Karg, Erwin; Tschiersch, Jochen

    2011-09-01

    Inhalation of indoor radon ((222)Rn) and thoron ((220)Rn) decay products is the most important source of exposure to ionizing radiation for the human respiratory tract. Decreasing ventilation rates due to energy saving reasons in new buildings suggest additional active mitigation techniques to reduce the exposure in homes with high radon and thoron concentrations but poor ventilation. Filtration techniques with HEPA filters and simple surgical mask material have been tested for their potential to reduce the indoor exposure in terms of the total effective dose for mixed radon and thoron indoor atmospheres. The tests were performed inside an experimental room providing stable conditions. Filtration (at filtration rates of 0.2 h(-1) and larger) removes attached radon and thoron decay products effectively but indoor aerosol as well. Therefore the concentration of unattached decay products (which have a higher dose coefficient) may increase. The decrease of the attached decay product concentrations could be theoretically described by a slowly decreasing exponential process. For attached radon decay products, it exhibited a faster but weaker removal process compared to attached thoron decay products (-70% for attached radon decay products and -80% for attached thoron decay products at a filtration rate of 0.5 h(-1) with an HEPA filter). The concentration of unattached thoron decay products increased distinctly during the filtration process (+300%) while that of unattached radon decay products rose only slightly though at a much higher level (+17%). In the theoretical description these observed differences could be attributed to the different half-lives of the nuclides. Considering both effects, reduced attached and increased unattached decay product concentrations, filtration could significantly decrease the total effective dose from thoron whereas the overall effect on radon dose is small. A permanent filtration is recommended because of the slow decrease of the thoron

  14. American Lung Association`s radon public information program

    SciTech Connect

    McCurdy, L.E.

    1992-12-31

    The American Lung Association (ALA), the nation`s oldest voluntary health organization, is dedicated to the conquest of lung disease and the promotion of lung health. The objective of the ALA Radon Public Information Program is to reduce public exposure to elevated indoor radon levels through implementing grassroots-based radon public awareness campaigns by 22 local ALA groups. The program, which is funded by a grant from the US Environmental Protection Agency (EPA), was initiated in December 1989; the first phase will continue until May, 1991. Activities of local Lung Associations include distribution of free or reduced-cost radon kits; presenting programs in elementary and secondary schools; presenting information on TV news series and talk shows, and on radio Public Service Announcements and talk shows; presenting articles and feature stories in the print media; holding conferences, workshops, and displays at fairs and other exhibitions; distributing radon fact sheets through libraries and utility company mailings; and distributing videos through video chains and libraries. The local Lung Associations also serve as promoters for the EPA/Advertising Council Radon Public Service Announcement Campaign. We will highlight the activities of the groups in communicating radon health risks to the public; we will describe the results obtained and will attempt to evaluate the merits of the various approaches on the basis of the initial results.

  15. An assessment of radon in groundwater in New York state.

    PubMed

    Shaw, Stephen B; Eckhardt, David A V

    2012-09-01

    A set of 317 samples collected from wells throughout New York State (excluding Long Island) from 2003 through 2008 was used to assess the distribution of radon gas in drinking water. Previous studies have documented high concentrations of radon in groundwater from granitic and metamorphic bedrock, but there have been only limited characterizations of radon in water from sedimentary rock and unconsolidated sand-and-gravel deposits in New York. Approximately 8% of the samples from bedrock wells exceed 89 Bq L (eight times the proposed regulatory limit), but only 2% of samples from sand-and-gravel wells exceed 44 Bq L. Specific metamorphic and sedimentary rock formations in New York are associated with the high radon concentrations, indicating that specific areas of New York could be targeted with efforts to reduce the risk of exposure to radon in groundwater. Additionally, radon in groundwater from the sand-and-gravel aquifers was found to be directly correlated to radon in indoor air when assessed by county. PMID:22850237

  16. An assessment of radon in groundwater in New York State

    USGS Publications Warehouse

    Shaw, Stephen B.; Eckhardt, David A.V.

    2012-01-01

    Abstract: A set of 317 samples collected from wells throughout New York State (excluding Long Island) from 2003 through 2008 was used to assess the distribution of radon gas in drinking water. Previous studies have documented high concentrations of radon in groundwater from granitic and metamorphic bedrock, but there have been only limited characterizations of radon in water from sedimentary rock and unconsolidated sand-and-gravel deposits in New York. Approximately 8% of the samples from bedrock wells exceed 89 Bq L-1 (eight times the proposed regulatory limit), but only 2% of samples from sand-and-gravel wells exceed 44 Bq L-1. Specific metamorphic and sedimentary rock formations in New York are associated with the high radon concentrations, indicating that specific areas of New York could be targeted with efforts to reduce the risk of exposure to radon in groundwater. Additionally, radon in groundwater from the sand-and-gravel aquifers was found to be directly correlated to radon in indoor air when assessed by county.

  17. An assessment of radon in groundwater in New York state.

    PubMed

    Shaw, Stephen B; Eckhardt, David A V

    2012-09-01

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

  18. The influence of thoron on instruments measuring radon activity concentration.

    PubMed

    Michielsen, N; Bondiguel, S

    2015-11-01

    Thoron, the isotope 220 of radon, is a radionuclide whose concentration may influence the measurement of the activity concentration of (222)Rn in the air. If in the case of continuous and active sampling measuring instruments, using a pump for example, the influence of thoron on radon measurement is obvious and is taken into account in the apparatus, it is often assumed that in the case of a passive sampling, by diffusion through a filter for example, this thoron influence is negligible. This is due to the very short radioactive half-life of thoron, 55.6 s (3.82 d for (222)Rn), and the assumption that the diffusion time of thoron in the detection chamber is long enough beside that of the thoron half-life. The objective of this study is to check whether this assumption is true or not for different kinds of commercial electronic apparatus used to measure radon activity concentration from soil to dwellings. First of all, the devices were calibrated in activity concentration of radon, and then they were exposed to a controlled thoron atmosphere. The experiments concerning the thoron aimed to investigate the sensitivity to thoron in the radon measuring mode of the apparatus. Results of these experiments show that all devices have a very quick answer to thoron atmosphere, even though the sensitivities vary from one instrument to another. Results clearly show that this influence on radon measurement due to the thoron is observed also after the exposition because of the decay of (212)Pb and its progenies. In conclusion, the sensitivity to thoron in the radon measuring mode depends strongly on the type of instruments. The results of the present investigation show that for some apparatus, the influence of thoron cannot be disregarded especially when measuring radon in soil.

  19. Radon exhalation rate in south-east Sicily building materials

    NASA Astrophysics Data System (ADS)

    Morelli, D.; Catal