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Sample records for 220rn exhalation rates

  1. Effect of ventilation rate on 220Rn concentration distribution in a model house

    In recent year, the dose associated with thoron and its decay products has gained considerable attention in India. This is mainly due to increasing awareness of thoron issue in coastal regions of India commonly known as High Background Radiation Areas (HBRAs) as well as in thorium and 232U handling occupational facilities. Thoron profiling is an important aspect for thoron dosimetry in these environments. Thoron (220Rn) is being a short lived (∼ 55 sec) element; it has been presumed that 220Rn concentration distribution pattern would not be significantly affected by ventilation rate. That is why higher value of 220Rn concentration was assumed near to the source such as wall etc. while beyond a particular distance no significant value of 222Rn concentration could be observed. To investigate the effect of ventilation rate on 220Rn concentration distribution, a controlled experimental study was carried out in laboratory model house at ISS, Germany at different ventilation rate of 0.5 h-1, 4.5 h-1 and 9.0 h-1. The model house of dimensions 2.8 m x 1.5 m x 1.8 m has one door and two windows in one of the long sides, is made of from unburned adobe bricks which are plastered with thick clay layer homogeneously enriched with powered granite. For obtaining the 220Rn concentration profile, 220Rn concentration was measured at different positions using sampling cup and indigenously developed portable thoron monitor (STM). It has been observed that 220Rn concentration profile itself varies with the ventilation rate. At the ventilation rate of 0.5 h-1 a gradient in 220Rn concentration profile was observed. 220Rn concentration was found higher near to the wall and decreasing towards the centre. On the contrary, at high ventilation rate of 4.5 h-1 and 9.0 h-1, a distorted 220Rn concentration profile was observed. This is due to the turbulent mixing caused by high ventilation rate. Hence, it can be emphasized that turbulent mixing plays a crucial role in deciding 220Rn

  2. Horizontal and vertical distribution of 222Rn and 220Rn in a dwelling, Bangalore, India

    The 222Rn and 220Rn have been identified as potential radiological health hazards and the dose estimation due to their exposure is an important task. Understanding their behavior in indoor environment helps in calculating the inhalation doses due to them. Effective doses due to inhalation of indoor 222Rn and its progeny account on an average for about one-half of all natural sources of radiation. However, recently the indoor surveys in Asia revealed that the dose contribution from 220Rn and its progeny can be equal to or even exceed that of 222Rn and its progeny. In view of this an attempt has been made to observe the distribution of 222Rn and 220Rn levels in a typical dwelling for the environment of Bangalore Metropolitan, India. Present study aims at the distribution of 222Rn and 220Rn concentrations in a typical dwelling. Higher concentrations were observed at the wall and flooring of the room and the concentrations were found to decrease as the detector is moved away from walls and floorings. The concentration of 222Rn is found to be invariant in indoor environment. An attempt has also been made to study the horizontal and vertical distribution pattern of 220Rn in a dwelling. The 220Rn concentration is found to drop exponentially as a function of distance from the source (wall/floor). Solution of one dimensional diffusion equation is used for regression fittings for 220Rn variation, from which the diffusion constants and the exhalation rates were calculated. The diffusion constants varied from 0.00195 to 0.00540 m2s-1. Results are discussed in detail

  3. Dose rate due to 226Ra, 232Th and indoor 222Rn/220Rn in Bangalore city

    Human beings have always been exposed to ionizing radiation from various natural sources of radiation and one of the major routes of internal exposures is through inhalation of radioactivity present in the atmosphere. External exposure is caused by the gamma radiation from 40K and the daughter products of 238U and 232Th. It is known that as a result of inhalation of 222Rn a daughter product of decay chain of 238U and its daughter products, the equivalent dose to the entire lung is 20% and 45% higher than the equivalent dose in other tissues. The present study is carried out in Bangalore Metropolitan, India during 2007 to till date. Activity concentrations were measured by hyper pure germanium detectors and 222Rn, 220Rn concentrations were measured by solid state nuclear track detectors. The dose conversion factors reported by UNSCEAR have been used to estimate the indoor inhalation dose rates. The absorbed dose rates due to 226Ra and 232Th ranged between 0.59 and 1.44 mSvy-1 with an AM as 0.93 mSvy-1. Whereas the dose rates during winter and summer ranged between 0.20 and 4.14 mSvy-1 with an arithmetic value 1.8 and 0.7 mSvy-1 respectively. The dose rates in lower volume rooms were ranged from 2.38 to 3.47 mSvy-1 and from 0.75 and 3.28 mSvy-1 for the rooms of higher volume. The arithmetic mean values of dose rates in lower and higher volume rooms were 2.94 ± 0.14 mSvy-1 and 1.35 ± 0.03 mSvy-1 respectively. Higher concentrations were observed in lower volume rooms than higher volume room of all the monitored locations. The detailed experimental methodology and results are discussed. (author)

  4. Thoron (220Rn) in the indoor environment

    Many locations around the world have higher levels of natural background radiation due to elevated levels of primordial radio nuclides in the soil and their decay products, like radon (222Rn), and thoron (220Rn) in the environment. Of late, technologically enhanced naturally occurring radioactive material has also contributed to the burden of background radiation. Since the contribution from inhalation of 222Rn, 220Rn and their short lived progenies contributes more than 54% of the total background radiation dose, it was necessary to supplement the external component with inhalation component. This component is not adequately estimated for the country so far on a national level. With this in mind, a national survey has been executed by this center involving a large number of universities and other allied research institutions from different parts of the country for the estimation of inhalation component of the dose rate arises from 222Rn, 220Rn and their short-lived progenies. This survey has been carried out using a twin cup radon-thoron dosimeter with solid state nuclear track based dosimeter developed and standardized at Bhabha Atomic Research Centre, Mumbai using LR-115 Type-II, of 12μm thick cellulose nitrate film as a detector. In this paper the contribution from 220Rn and its progenies to the inhalation component is presented. Present study reveals that 220Rn and its progeny contributes nearly 20% of the total dose rate to radon, thoron and their progenies. Paper presents the method measurements and the results obtained. Data available in literature is also compared. (author)

  5. 220Rn in geothermal steam

    The isotope 220Rn (half-life 56 seconds) occurs in fumaroles in Japan and Taiwan, in amounts as high as 1000 times the 222Rn content. The authors report its presence in geothermal steam at Wairakei, New Zealand, in amounts as high as 130 times those of 222Rn. It is detected by a radiochemical separation of Pb, and gamma spectrometry. Some of the 220Rn/222Rn ratios are higher than theoretically expected, but have frequently been reported from similar locations. Theories of possible origins will be discussed. 22 refs., 1 tab

  6. Response of AlphaGUARD radon detector to 220Rn

    Based on optimized-design ionization chamber, AlphaGUARD is the most stable commercial radon detector, which is widely used in various radon chambers worldwide as a standard device. Under ordinary radon concentration, it works according to the principle of pulse ionization chamber which only records the α particle counting without the spectroscopy, so it is limited to pure 222Rn measurements. In this paper, the two working modes of response mechanisms of AlphaGUARD to 220Rn were studied. This study found that, under flow mode with sampling flow rate of 1.0 L·min-1, the flow correction factor for 220Pm is 0.80; under diffusion modes, the relative sensitivity coefficient of 220Rn is independent on the 220Rn concentration and mixed 222Rn/220Rn ratio is 6.09%. (authors)

  7. Investigation of the level of radionuclide on 222Rn/220Rn and of γ dose rate in underground coal mines in Hebei province

    Objective: To investigate the level of radionuclide in underground coal mines at Tangshan district in Hebei province. Methods: The radon concentration and γ dose rate of four underground coal mines were measured with accumulative method and instant method. The activity concentration of radionuclide was measured with high pure germanium (HPGe) spectrum. Result: The accumulative measurement at four coal mines in the district show that 222Rn concentration is 50.1Bq/ m3, 220Rn is about 38.4 Bq/m3 and γ dose rate of underground coal mines is 108nGy/h; Instant measurement indicates that radon concentration is 8.7 ± 17.0 Bq/m3 and γ dose-rate is 67nGy/h at the earth surface; the arithmetic mean values of activity concentration of radionuclides for 238U, 226Ra, 232Th, 40K are 39.6, 31.3, 36.3, 26.0Bq/kg, respectively. Conclusion: Radon concentrations in underground coal mines are higher than that in the open environment. Contents of radionuclide of coal are all apparent lower than that of average of the whole counter. The normalized collective dose is 4.67 man·mSv (Mt)-1. (authors)

  8. Field measuring of radon exhalation rate from the soil by CR-39 detector

    As known, the soil under a building is contributing to overall volume activities of radon indoor. As numerous data are show, the actual values of radon exhalation rate (RER) of the same soil under laboratory and field conditions are different in tens and sometimes-even hundreds of times. Because in the real conditions, the values of RER depend on many factors: the underground cracks and voids; temperature and pressure gradients; humidity, porosity and density of the soils. These destabilizing factors of the nature an increasing of convection distances of gases of the 222Rn and 220Rn in medium of air. The paper filters that used in measuring chambers are passed both particles; radon and thoron. Visual determination of energy of α-particles by the shape of the tracks is very difficult. In order to determine the real value of 222Rn, it is necessary to take into contribution of 220Rn in total number of tracks or stop the entrance of 220Rn into the chamber using a special filter that transmits 222Rn only. However, because of the absence of such filters, we prefer to use another method, delaying of the short-lived 220Rn in the chamber air, creating impeding barrier against it. The aim of this work was the build-up two-chamber registrar with two detectors of CR-39 for field determination of exhalation rate of the 220Rn+ 222Rn and 222Rn from soil. The values of exhalation of the radon-222 from soils were found equal to 22.1 ± 4.8 and 16.2 ± 3.8 Bq/m2h for spring and summer seasons, respectively. The laboratory determination of the RER in same soils has shown the mean value is 0.10 ± 0.02 Bq/m2h. The values of RER in field 160-200 times more than laboratory measurements from the same soils. Such a large difference in the values of radon exhalation from the soil, suggests that environmental factors strongly influence the results of the field measurements of RER. The values of radon exhalation rate from the soils depend on the season also

  9. Nationwide indoor 222Rn and 220Rn map for India: a review

    Considering the role of radon in epidemiology, an attempt was made to make a nation-wide map of indoor 222Rn and 220Rn for India. More than 5000 measurements have been carried out in 1500 dwellings across the country comprising urban and nonurban locations. The solid state nuclear track detectors based twin cup 222Rn/220Rn discrimination dosimeters were deployed for the measurement of indoor 222Rn, 220Rn and their progeny levels. The geometric means of estimated annual inhalation dose rate due to indoor 222Rn, 220Rn and their progeny in the dwellings was 0.94 mSvy-1 (geometric standard deviation 2.5). It was observed that the major contribution to the indoor inhalation dose was due to indoor 222Rn and its progeny. However, the contribution due to indoor 220Rn and its progeny was not trivial as it was found to be about 20% of the total indoor inhalation dose rates. The indoor 222Rn levels in dwellings was significantly different depending on the nature of walls and floorings. - Highlights: → A countrywide survey on 222Rn and 220Rn levels for India was carried out in dwellings. → The regional values are obtained from the data on a few houses in that area. → Calibration factors for the measurements were derived experimentally as well as theoretically. → The 222Rn and 220Rn levels are represented on the maps.

  10. Field measurement of radon exhalation rate from the soil by CR-39 detector

    Determination technique of radon exhalation rate (RER) from soils in field measured by track detector CR-39 was developed. For this purpose, the method 'Russian dolls' (matrieshka) was created and used, consisting of three cylindrical plastic chambers and located inside each other. Entrance mouths of chambers are installed in opposite directions to make an artificial barrier up on the path of 220Rn. Field measurements of the RER from soils were within 16.4-22.1 Bq/m2h, that are 160 and 220 times more than laboratory measurement. The RER values from soils as laboratory and field measurements have been compared with the data of other authors. (author)

  11. Thoron (220Rn) in the indoor atmospheric environment

    Naturally occurring background radiation is a topic, which has evoked curiosity and concern between the scientist and layman alike in recent years due to the shift in focus of health effects due to exposure of radiation from acute high level to chronic low level. Many locations around the world have higher levels of natural background radiation due to elevated levels of primordial radio nuclides in the soil and their decay products like radon (222Rn), and thoron (220Rn) in the environment. Of late, technologically enhanced naturally occurring radioactive material has also contributed to the burden of background radiation. It has been estimated that inhalation of 222Rn, 220Rn and their short lived progenies contribute more than 54% of the total natural background radiation dose received by the general population. In the Indian context, in an earlier national survey, the external gamma radiation dose rates have been more or less well mapped using thermo luminescent dosimeters covering more than 214 locations, which has yielded a national average of 775 mGy/y. Of this, nearly 48.7% contribution of the dose rate is from 40K and the rest from the uranium (33.6%) and thorium (17.7%) series. A good database pertaining to the country wide levels of uranium, thorium and potassium in geological materials also exists. Thus, there exists a good database on the total external gamma radiation level across the country. Since the contribution from inhalation of 222Rn, 220Rn and their short lived progenies contributes more than 54% of the total background radiation dose, it was necessary to supplement the external component with inhalation component. This component is not adequately estimated for the country so far on national level. With this in mind, a national survey has been executed by this center involving a large number of universities and other allied research institutions from different parts of the country for the estimation of inhalation component of the dose rate

  12. Realization and characterization of a 220Rn source for calibration purposes

    The recent interest for measuring 220Rn activity in air and the following development of the corresponding measurement techniques require the improvement of standards for the calibration and characterization of the measurement devices. Due to the short half-life of the 220Rn, the adopted techniques for the production of 222Rn sources are not always reliable. In this paper a methodology for realizing a thoron known activity starting from a 232Th source will be presented and discussed. - Highlights: • A thoron source realized by well characterized samples containing thorium. • Methodology for measuring exhalated thoron activity by gamma ray spectrometry. • Stable on time thoron specific activity concentration in air. • Radon isotopes spectroscopy by electrostatic collection

  13. Study on 220Rn equilibrium factor in China traditional dwellings

    The spatial distribution and seasonal variation of 220Rn concentration (CTn) and its progeny concentration (Cp,Tn) in China traditional dwellings constructed with soil were studied. The results show that the spatial distribution of CTn appears a significant concentration gradient, and decreases exponentially from the distance of source (bare walls or ground), while there is a good linearity and repeatability. The seasonal variation of CTn displays maximum value in autumn and minimum value in winter. The seasonal variation of Cp,Tn comparing with CTn and Cp,Rn is similar, and its spatial variation can be ignored. Therefore, fixing the distance distance of 220Rn form source, there is a definite relationship between CTn and Cp,Tn. 220Rn equilibrium factors FTn respectively are 0.003±0.001 and 0.017±0.014 at the distances of 2.5 cm and 20 cm from wall. The Cp,Tn results of actual measurement in traditional houses are in good agreement with the calculated values by using FTn. The measurement to 220Rn gas is more easily achieved comparing with 220Rn progenies. The introduction of FTn provides a simple and reliable method for assessment of 220Rn exposure. (authors)

  14. Indoor 222Rn and 220Rn variations as an evidence for Boyle's law

    The 222Rn and 220Rn levels were measured for Bangalore Metropolitan, India was focused on various types of houses with respect to ventilation characteristics. Dimension of room was taken into account to correlate the air rate the virtue of number of windows and ventilation openings. Integrated and long-term measurements of radon were carried out in the dwellings using twin cup dosimeters with Solid State Nuclear Track Detector. Result shows that the concentration exponentially with the increase in room volume. (author)

  15. Indoor 222Rn and 220Rn concentrations and doses in Bangalore, India

    222Rn and 220Rn levels have been measured using passive detector technique by employing time integrated solid-state nuclear track detector-based dosemeters in various types of houses at 10 different locations in and around Bangalore Metropolitan, India. The measured geometric mean concentration values of 222Rn and 220Rn levels in 200 dwellings of different types of construction were found to be 32.2±1.6 and 21.4±1.0 Bq m-3, respectively. The dose rate received by the population of Bangalore ranged between 0.2 and 3.5 mSv y-1 with an average and the geometric mean of 1.14±0.05 and 1.06 mSv y-1, respectively. Overall, the result does not show much significant radiological risk for the inhabitants and the 222Rn levels are well within the limits of global average concentration of 40 Bq m-3. However, the 220Rn levels observed were found to be higher than the global average of 10 Bq m-3. (authors)

  16. Using 220Rn to calibrate liquid noble gas detectors

    Kobayashi, M; Takeda, A; Kishimoto, K; Moriyama, S

    2016-01-01

    In this paper, we describe 220Rn calibration source that was developed for liquid noble gas detectors. The key advantage of this source is that it can provide 212Bi-212Po consecutive events, which enables us to evaluate the vertex resolution of a detector at low energy by comparing low-energy events of 212Bi and corresponding higher-energy alpha-rays from 212Po. Since 220Rn is a noble gas, a hot metal getter can be used when introduced using xenon as the carrier gas. In addition, no long-life radioactive isotopes are left behind in the detector after the calibration is complete; this has clear advantage over the use of 222Rn which leaves long- life radioactivity, i.e., 210Pb. Using a small liquid xenon test chamber, we developed a system to introduce 220Rn via the xenon carrier gas; we demonstrated the successful introduction of 6 times 10^2 220Rn atoms in our test environment.

  17. Thoron (220Rn) in the indoor environment and work places

    Ever since studies on uranium miners established the presence of a positive risk coefficient for the occurrence of lung cancer in miners exposed to elevated levels of 222Rn and its progeny, there was a great upsurge of interest in the measurement of 222Rn in the environment. Subsequently, considerable data is being generated on the levels of 222Rn in the environment across the worlds and is being periodically reported by UNSCEAR reports. In contrast to this, data pertaining to 220Rn in indoors and workplace environment is scaree due to the general perception that its levels are negligible due to its shorter half life, and subsequently its contribution to the total inhalation dose is ignored, in the presence of other significant sources of natural radiation. This may not be true. Globally many locations have higher levels of natural background radiation due to elevated levels of primordial radio nuclides in the soil and their decay products like radon (222Rn), and thoron (220Rn) in the environment. Of late, technologically enhanced naturally occurring radioactive material has also contributed to the burden of background radiation. It is estimated that inhalation of 222Rn, 220Rn and their short lived progenies contribute more than 54% of the total natural background radiation dose received by the general population. 220Rn problem exists in industries which use thorium nitrate. Including India, lamps using thoriated gas mantles are still being used for indoor and outdoor lighting and by hawkers in rural as well as urban areas. Considering the fact that large amount of thorium nitrate is being handled by these industries, contribution to the inhalation dose of workers from 220Rn gas emanated and build up of the progeny in ambient air may also be quite significant. In this paper current status of 220Rn levels in the indoor environment and workplaces as well as in other industries where large amount of 232Th is being handled is being summarized. Methods of measurement

  18. In situ soil 222Rn and 220Rn and their relationship with meteorological parameters in tropical Northern Peninsular Malaysia

    This study focused on the relationship between soil 222Rn and 220Rn concentrations and meteorological parameters (temperature, pressure, humidity, and terrestrial gamma radiation) in Northern Peninsular Malaysia. Measurements of in situ soil 222Rn and 220Rn concentrations were performed in surface air and at a sampling depth of 50 cm using two active techniques: RAD7 radon detector and radon continuous monitor (Sun Nuclear Corporation). The surface air 222Rn concentration ranged from 6 Bq m−3 to 79 Bq m−3, whereas at the depth of 50 cm, the 222Rn and 220Rn concentrations varied from 133 Bq m−3 to 143,059 Bq m−3 and from 55 Bq m−3 to 403 Bq m−3, respectively. The gamma dose rate (DR) in air was measured using a GR-135 spectrometer (Exploranium). The dose rate varied from 80 nGy h−1 to 258 nGy h−1. The 222Rn concentration in the soil (143 kBq m−3) was high considering that the concentration in typical soil samples is only 40 kBq m−3. The 222Rn concentration in surface air varied within the recommended activity values prescribed by the United States Environmental Protection Agency and the International Commission on Radiological Protection. Weak positive and negative correlations were observed between the (222Rn and 220Rn) concentrations and the meteorological parameters. - Highlights: • DR varies (80–258 nGy h−1), no correlation between acidity and radon concentration. • 222Rn in soil (143 kBq m−3) high considering than in typical soil 40 kBq m−3. • 222Rn in surface air varied within EPA and ICRP. • All sites exhibited larger DR compared with the world of 84 nGy h−1 except for two sites. • A statistically significant correlation between 222Rns–220Rn

  19. Radon exhalation rates of some granites used in Serbia

    Nikolić Mladen D.

    2015-01-01

    Full Text Available In order to address concern about radon exhalation in building material, radon exhalation rate was determined for different granites available on Serbian market. Radon exhalation rate, along with mass exhalation rate and effective radium content were determined by closed chamber method and active continuous radon measurement technique. For this research, special chambers were made and tested for back diffusion and leakage, and the radon concentrations measured were included in the calculation of radon exhalation. The radon exhalation rate ranged from 0.161 Bq/m2h to 0.576 Bq/m2h, the mass exhalation rate from 0.167 Bq/kgh to 0.678 Bq/kgh, while the effective radium content was found to be from 12.37 Bq/kg to 50.23 Bq/kg. The results indicate that the granites used in Serbia have a low level of radon exhalation.

  20. Precursory Subsurface 222Rn and 220Rn Degassing Signatures of the 2004 Seismic Crisis at Tenerife, Canary Islands

    Pérez, Nemesio M.; Hernández, Pedro A.; Padrón, Eleazar; Melián, Gladys; Marrero, Rayco; Padilla, Germán; Barrancos, José; Nolasco, Dácil

    2007-12-01

    Precursory geochemical signatures of radon degassing in the subsurface of the Tenerife Island were observed several months prior to the recent 2004 seismic-volcanic crisis. These premonitory signatures were detected by means of a continuous monitoring of 222Rn and 220Rn activity from a bubbling CO2-rich gas spot located at 2.850 m depth inside a horizontal gallery for groundwater exploitation at Tenerife. Multivariate Regression Analysis (MRA) on time series of the radon activity was applied to eliminate the radon activity fluctuation due to external variables such as barometric pressure, temperature and relative humidity as well as power supply. Material Failure Forecast Method (FFM) was successfully applied to forecast the anomalous seismicity registered in Tenerife Island in 2004. The changes in the 222Rn/220Rn ratio observed after the period of anomalous seismicity might suggest a higher gas flow rate and/or changes in the vertical permeability induced by seismic activity.

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

    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 (222Rn and 220Rn) 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 222Rn and 220Rn and their decay products is not well quantified. Towards this, systematic indoor surveys were conducted wherein simultaneous measurements of time integrated 222Rn and 220Rn 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 222Rn and 220Rn gas and their decay products in these HBRAs are in the same range as observed in the NBRAs in India. - Highlights: • Measurements of 222Rn, 220Rn and their progeny in indoors of HBRAs of India. • DTPS/DRPS deposition sensors were used for measurement progeny of 222Rn and 220Rn. • Inhalation doses were in HBRAs were comparable with those in NBRAs

  2. A study of indoor 220Rn and 222Rn decay product concentrations in the UK

    In order to gain a better understanding of the risk of human exposure to 220Rn indoors, measurements of Rn decay products have been performed in a number of houses in England. The study focused mainly on areas where above-average indoor 220Rn concentrations were to be expected because of geological or other factors. Thoron (220Rn) in room air comes mainly from the building materials, with an additional contribution from soil gas; therefore, 220Rn concentrations were examined in relation to building materials as well as location. Measurements were carried out in 23 houses. The mean equilibrium equivalent 220Rn (EET) concentration found was 0.39 Bq m-3 and the mean equilibrium equivalent 222Rn (EER) concentration was 17.8 Bq m-3. The 220Rn concentration values and EET/EER ratios found in this investigation correspond well with other published results. Values imply that the 220Rn concentrations in English dwellings are a far less important problem than 220Rn concentrations. (authors)

  3. 222Rn + 220Rn monitoring by alpha spectrometry

    Controlled 222Rn + 220Rn mixed atmospheres have been realised introducing calibrated sources in a stainless steel chamber. An electrostatic alpha monitor internal to the chamber has been used for an accurate discrimination of alpha peaks due to the products of the two isotopes. In the chamber, different specific activities are achieved in order to test the response of the internal reference instrument and to evaluate the possible interferences due to contemporary presence of both radon isotopes. Results show that: (i) the atmospheres are very stable, (ii) the monitor is adequate for their control because the various alpha lines are well evaluated and (iii) using TyvekR filter, the efficiency of monitor is stable and constant vs. activity. (authors)

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

    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

  5. Research on measurement method of 220Rn progeny aerosol size distribution

    The method for measuring 220Rn progeny aerosol activity particle size distributions was introduced through ELPI system, α spectroscopy and the energy discrimination method. The different particle sizes of the 220Rn progeny aerosols were collected and the activity size distributions in the 220Rn laboratory of the University of South China were measured by this method. The experiment results show that the activity median aerodynamic diameter (AMAD) of ThB aerosol is 237 nm, and that of ThC is 245 nm. The simple and quick method can be used to monitor the particle size distributions of 220Rn progeny aerosol in real time, the aerosol activity size distributions of ThB and ThC can be obtained by this method at the same time, and the measurement accuracy of the energy spectrum is higher than that of custom method. (authors)

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

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

  7. 222Rn and 220Rn concentrations in soil gas of Karkonosze-Izera Block (Sudetes, Poland)

    Soil gas 222Rn and 220Rn concentrations were measured at 18 locations in the Karkonosze-Izera Block area in southwestern Poland. Measurements were carried out in surface air and at sampling depths of 10, 40 and 80 cm. Surface air 222Rn concentrations ranged from 4 to 2160 Bq m-3 and 220Rn ranged from 4 to 228 Bq m-3. The concentrations for 10 and 40 cm varied from 142 Bq m-3 to 801 kBq m-3 and 102 Bq m-3 to 64 kBq m-3 for 222Rn and 220Rn, respectively. At 80 cm 222Rn concentrations ranged from 94 Bq m-3 to >1 MBq m-3. The 220Rn concentrations at 80 cm varied from 45 Bq m-3 to 48 kBq m-3. The concentration versus depth profiles for 222Rn differed for soils developed on fault zones, uranium deposits or both. Atmospheric air temperature and soil gas 222Rn and 220Rn were negatively correlated. At sampling sites with steep slopes, 220Rn concentrations decreased with depth

  8. 222Rn, 220Rn and their progeny concentrations in offices in Hong Kong

    An active sampling system using charcoal canisters and an HPGe γ-spectrometer was employed to survey 222Rn and 220Rn concentrations in 65 offices in Hong Kong, and a traditional method was used to record simultaneously the potential α-energy concentrations (PAEC) of 222Rn and 220Rn progeny at the same sites. The mean values of gas concentration, PAEC and equilibrium factor for 222Rn were 48±32 Bq m-3, 5.2±5.1 mWL and 0.38±0.13, respectively, and the corresponding values for 220Rn were 14±7 Bq m-3, 2.7±2.1 mWL and 0.050±0.016. These values were in general higher than those in dwellings in Hong Kong, which was due to the poorer fresh air exchange in offices. Factors affecting the concentrations of 222Rn, 220Rn and their progeny were also studied. The type of air conditioners and the indoor and outdoor temperature difference show some effects on 222Rn, 220Rn and progeny concentrations, while rainfall and relative humidity affect only the progeny concentrations

  9. Peak tailing correction in measurement of 222Rn/220Rn activity concentration with α spectrum method

    α spectrum method is one of the most important methods in measurement of 222Rn/220Rn concentration in environment. However, the peak tailing from high energy particles is an obstacle for accurate measurement. To improve the accuracy of measurement, study on the mechanism and effect of the tailing were carried out, and calibrating experiments on peak tailing correction factors were also realized using ERS-2 monitor. The peak tailing correction factors and calibration factors of 222Rn and 220Rn were measured by experiment and their accuracy were also tested. It is suggested that during calibrating α spectrum monitor of 222Rn/220Rn activity concentration, the peak tailing correction and calibration factors should be recalibrated if necessary. (authors)

  10. CFD based simulation of thoron ((220)Rn) concentration in a delay chamber for mitigation application.

    Agarwal, T K; Sahoo, B K; Gaware, J J; Joshi, M; Sapra, B K

    2014-10-01

    The release of (220)Rn gas (conventionally referred to as thoron) is an issue of concern from the radiological point of view for occupational environments pertaining to the thorium fuel cycle. Studies for understanding its release and developing systems to control it are crucial for exposure control research. A thorough study of the "Delay Volume Technique" for mitigation of (220)Rn has been carried out. Experiments have been carried out with (220)Rn source and associated measurement system in a cubical chamber (delay chamber) of 0.5 m(3) volume. For different flow conditions and inlet-outlet positions, (220)Rn transmission factor has been obtained. Computational Fluid Dynamics (CFD) technique has been employed for these experimental conditions and the simulated transmission factors have been compared. The results show that the flow and the position of the inlet and outlet play an imperative role in the transportation, mixing and subsequent mitigation of thoron inside the chamber. Predictive capability of CFD technique for such delay volume experiments has been validated in this work. A comparison has been made with uniform mixing model and it is found that the results of simulation differ appreciably from that of uniform mixing model at the tested flow regime. PMID:24860913

  11. Measurement of the indoor and outdoor 220Rn (thoron) equilibrium factor: Application to lung dose

    A miniature four-chamber alpha track detector was developed that measures both 222Rn (radon) and 220Rn (thoron), in duplicate. Using this detector and the previous long-term measurements of the 220Rn decay products 212Pb, and 212Bi, an equilibrium factor, Feq, is derived for both outdoor and indoor 220Rn environments (0.004+0.001 outdoors and 0.04+0.01 indoors). The lung airway dose can then be calculated from a dose factor from UNSCEAR that requires the equilibrium equivalent thoron concentration (EEC), i.e. the product of Feq and the 220Rn gas concentration. The lung dose from thoron in domestic or occupational surveys is often overlooked. The values of Feq for thoron in several published studies are in general agreement with the values reported here. Thus, a long-term alpha track measurement of thoron multiplied by an appropriate indoor or outdoor equilibrium factor yields the EEC, which can be used to assess bronchial lung dose. (authors)

  12. Measurements of 222Rn and220Rn with a large size collector of radon progeny

    People have paid more attention to radon since 1980s. Radon concentrations in high background radiation areas in the south are higher than others in China, especially 220 Rn concentration is significantly high. Therefore, measurement of 222 Rn and 220 Rn concentration should be carried out there. I will introduce a large size collector of radon progeny and its applications in this paper. The collector is a sheet of polyvinyl chloride fibre with electrostatics of -500V ∼ -700V. Its size (60mm in diameter) is larger than others (26mm in diameter) that work as the same principle. The collector is more effective to adsorb radon progeny than most of others. The equipment of ZnS(Ag) Scintillation Counting System is available for large size collectors to detect radon progeny. Therefore its sensitivity of measurement is high than others. According to the different half life of radon progeny and based on both theory and experiment, a formula for discrimination and calculation of 222 Rn and 220 Rn concentrations was deduced. The 222 Rn and 220 Rn concentrations were surveyed with electrostatic collectors of radon progeny on the campus of commercial school and some other areas in Hainan, southern China. Neither 222 Rn nor 220 Rn concentrations were found significant high. However several faults underground were delineated. The collector is also used to study radon transportation. Results indicate that radon changes regularly with date when it has transported for a certain distance. Velocities of radon migration in the four media are quite different. Radon migrates more quickly in vertical tube than in the horizontal tube

  13. Measurements of 222Rn and 220Rn with a Large Size Collector of Radon Progeny

    Wu Qifan; Jia Wenyi; Fang Fang; Wang Jun; Cheng Jianping; Liu Guilin; Zhu Li

    2003-01-01

    Radon concentrations in high background radiation areas in the south are higher than those of others in China, especially 220Rn concentration is significantly high. Therefore, measurements of 222Rn and 220 Rn concentrations should be carried out there. This paper introduces a large size collector of radon progeny and its applications. The collector is a sheet of polyvinyl chloride fiber with electrostatics of (-500 V) - ( -700 V). Its size (60 mm in diameter) is larger than those of others (26 mm in diameter) that work with the same principle. The collector is more effective to adsorb radon progeny than most of others. The equipment of ZnS(Ag) Scintillation Counting System is available for large size collectors to detect radon progeny. Therefore, its sensitivity of measurement is higher than that of others.According to the different half lives of radon progeny, and based on both theory and experiments, a formula for discrimination and calculation of 222 Rn and 220Rn concentrations is deduced. The 222Rn and 220Rn concentrations were surveyed with electrostatic collectors of radon progeny on the campus of com-mercial school and some other areas in Hainan, southern China. Neither 222Rn nor 220Rn concentration was found significantly high. However, several faults underground were delineated. The collector is also used to study radon transportation. Results indicate that radon changes regularly with date when it has transported for a certain distance. Velocities of radon migration in the four media are quite different.Radon migrates more quickly in vertical tube than in the horizontal tube.

  14. The Distribution Characteristics of 222Rn and 220Rn Concentrations in Soil Gas In Zhongshan City, Guangdong Province, China

    A mapping survey of 222Rn and 220Rn concentrations in soil gas was conducted for the first time using a RAD7 portable radon monitor at 67 locations across an area of 1800 km2 in Zhongshan City (ZSC), Guangdong Province. It was found that 222Rn concentrations increased with increasing depth, whereas 220Rn concentrations were almost unchanged at different depths. The sites with high 222Rn values were located mainly in granite outcrops, while those with low values were located in a sedimentary region. The distribution patterns of 220Rn coincide with the patterns of activity concentration of 232Th in soil. (author)

  15. Revision for measuring radon exhalation rate in open loop

    Tan, Y.; Xiao, D.; Yuan, H.; Tang, Q.; Liu, X.

    2013-01-01

    We propose a novel method for quickly measuring the radon exhalation rate in open loop. We first obtain the temporal variation of radon concentration in the internal cell of the RAD7 by analyzing the work principle of RAD7. We then obtain the temporal variation of radon concentration in the ventilation-type accumulation chamber when the effects of leakage and back diffusion are neglected. This method uses the measured value before the radon concentration in the ventilation-type accumulation chamber reaches a steady state. The diameter of the air input tube to the ventilation-type accumulation is large enough to keep the differential pressure in the accumulation chamber and outdoors negligible. Short cycle time and large flow rate will be appropriate for reducing measurement error. Several radon exhalation rate measurements of the medium surface have been performed in the Radon Laboratory of the University of South China. The radon exhalation rates obtained by verification experiments are in good agreement with the reference value. This method can be applied to develop and improve the instruments for measuring radon exhalation rate.

  16. Revision for measuring radon exhalation rate in open loop

    We propose a novel method for quickly measuring the radon exhalation rate in open loop. We first obtain the temporal variation of radon concentration in the internal cell of the RAD7 by analyzing the work principle of RAD7. We then obtain the temporal variation of radon concentration in the ventilation-type accumulation chamber when the effects of leakage and back diffusion are neglected. This method uses the measured value before the radon concentration in the ventilation-type accumulation chamber reaches a steady state. The diameter of the air input tube to the ventilation-type accumulation is large enough to keep the differential pressure in the accumulation chamber and outdoors negligible. Short cycle time and large flow rate will be appropriate for reducing measurement error. Several radon exhalation rate measurements of the medium surface have been performed in the Radon Laboratory of the University of South China. The radon exhalation rates obtained by verification experiments are in good agreement with the reference value. This method can be applied to develop and improve the instruments for measuring radon exhalation rate.

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

    Mehta, Vimal [Deptt of Physics, M. M. University, Mullana (Ambala)-133 207 (India); Deptt of Physics, Punjabi University, Patiala- 147 001 (India); Singh, Tejinder Pal, E-mail: tejinders03@gmail.com [Deptt of Physics, S.A. Jain (P.G.) College, Ambala City- 134 003 (India); Chauhan, R. P. [Deptt of Physics, National Institute of Technology, Kurukshetra- 136 119 (India); Mudahar, G. S. [Deptt of Physics, Punjabi University, Patiala- 147 001 (India)

    2015-08-28

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

  18. A 220Rn source for the calibration of low-background experiments

    Lang, R. F.; Brown, A.; Brown, E.; Cervantes, M.; Macmullin, S.; Masson, D.; Schreiner, J.; Simgen, H.

    2016-04-01

    We characterize two 40 kBq sources of electrodeposited 228Th for use in low-background experiments. The sources efficiently emanate 220Rn, a noble gas that can diffuse in a detector volume. 220Rn and its daughter isotopes produce α-, β-, and γ-radiation, which may used to calibrate a variety of detector responses and features, before decaying completely in only a few days. We perform various tests to place limits on the release of other long-lived isotopes. In particular, we find an emanation of detectors employing liquid noble elements such as argon and xenon. With the source mounted in a noble gas system, we demonstrate that filters are highly efficient in reducing the activity of these longer-lived isotopes further. We thus confirm the suitability of these sources even for use in next-generation experiments, such as XENON1T/XENONnT, LZ, and nEXO.

  19. Relationship of 220Rn and 222Rn progeny levels in Canadian underground U mines

    Radon-222 and 220Rn progeny are found in some Canadian underground U mines. Because both can contribute to lung dose, their experimental determinations are important. The relationship between 222Rn progeny Working Level [WL(Rn)] and 220Rn progeny Working Level [WL(Tn)] has been investigated in U mines. Experimental measurements extended from 1981 to 1986 and consisted of about 700 measurements of each WL(Rn) and WL(Tn). The data were analyzed by standard linear and power-function regression analysis. A power-function relationship between WL(Rn) and WL(Tn) seemed to fit the experimental data best. The relationship obtained permits the calculation of WL(Tn) from experimental values of WL(Rn). The relationship is useful for lung-dose-calculation purposes and in mine-ventilation-engineering calculations

  20. GUM approach to uncertainty estimations for online 220Rn concentration measurements using Lucas scintillation cell

    It is now widely recognized that, when all of the known or suspected components of errors have been evaluated and corrected, there still remains an uncertainty, that is, a doubt about how well the result of the measurement represents the value of the quantity being measured. Evaluation of measurement data - Guide to the expression of Uncertainty in Measurement (GUM) is a guidance document, the purpose of which is to promote full information on how uncertainty statements are arrived at and to provide a basis for the international comparison of measurement results. In this paper, uncertainty estimations following GUM guidelines have been made for the measured values of online thoron concentrations using Lucas scintillation cell to prove that the correction for disequilibrium between 220Rn and 216Po is significant in online 220Rn measurements

  1. Radon activity and exhalation rates in Indian fly ash samples

    Fly ash is the by-product of burnt coal which is naturally occurring radioactive material (NORM). Because of human activity and its use in manufacturing of bricks, sheets, cement, land filling etc. may present a radiation hazard to people and the environment. Thus, it is very important to carry out radioactivity measurements in fly ash from the health and hygiene point of view. In the present study, the activity concentrations of 238U, 232Th and 40K have been varied from 99 ± 2 to 203 ±4 Bq/kg, 145 ± 2 to 288 ± 4 Bq/kg, and 355 ± 5 to 516 ± 6 Bq/kg, respectively in various fly ash samples. The radium equivalent activity was varied from 317 to 614 Bq/kg, radon activity varied from 214 to 590 Bq/m3, radon exhalation rate varied from 7.8 to 21.6 inBqkg-1h-1 for mass exhalation rate and from 138 to 381 mBqm2h-1 for surface exhalation rate in the fly ash samples used in the present investigation. The absorbed dose varied from 143 to 277 nGyh-1, the indoor annual effective dose varied from 0.70 to 1.36 mSv and the outdoor annual effective dose varied from 0.17 to 0.34 mSv. In all the samples, the activity concentration of 238U, 232Th and 40K was found to be below the permissible levels. A strong positive correlation has been observed between uranium concentration, radon activity and radon exhalation rate. (author)

  2. Radon exhalation rate of soil in Chamaraja Nagar area, India

    Human beings are continuously exposed to ionizing radiation from natural sources. The main contributors to natural radiation are high-energy cosmic radiation and radioactive nuclides that originates in the earths crust. 222Rn a decay product of 226Ra in the naturally occurring 238U series is a radioactive inert gas and constitutes about half the radiation dose received by general population. The amount of radon that escapes from the earth depends mainly on the amounts of radium in the ground along with other factors, like the type of the soil cover, porosity, etc. The majority of radiation exposure of the population comes from radon an á-radioactive, inert gas. Radon produces the main natural radiation exposure for human beings and has been recognized as carcinogenic gas. In the present study Radon exhalation rate and Radium concentration in soil and rock samples around Chamaraja Nagar area of Karnataka state, India, are measured by SSNTD method, using can technique and LR-115 type II detectors. The radium activity in rock sample varies from 2.9 to 39.5 Bqkg-1. Mass and Surface exhalation rate of radon in rock samples varies from 8.1 to 119.7 mBqkg-1h-1 and 454.7 to 1787.3 mBqm-2h-1 respectively. Radium concentration in soil samples has been found to vary from 3.6 to 34.1 Bqkg-1 with an average value of 16.5 Bqkg-1. The surface exhalation rate of radon 142 to 1377.3 mBqm-2h-1. The mass exhalation rate of radon in soil samples has been found to vary from 10 to 31.4 mBqkg-1h-1, with an average value of 19.3 mBqkg-1h-1 and standard deviation of 7.6. (author)

  3. Effect of 220Rn gas concentration distribution on its transmission from a delay chamber: evolving a CFD-based uniformity index

    220Rn mitigation can be achieved by delay chamber technique, which relies on the advantage of its short half-life. However, flow rate as well as inlet-outlet position for the delay chamber can have a significant impact on 220Rn concentration distribution patterns and hence transmission factor. In the present study, computational fluid dynamics simulations to estimate the concentration distribution has been carried out in a chamber of 0.5 m3 for the combination of six different inlet-outlet positions and five different flow rates. Subsequently, the transmission factor (TF) for the chamber was evaluated and found to be highly dependent on the flow rate and inlet-outlet positions. For ease of scale up, the dependency of TF on the flow rate and the inlet-outlet positions is best summarised by relative transmission factor (RTF), which is the ratio of the TFs for the case of inlet and outlet on different faces to that on the same face. (authors)

  4. 222Rn, 220Rn and other dissolved gases in mineral waters of southeast Brazil

    This paper describes the natural radioactivity due to 222Rn and 220Rn in mineral waters occurring at São Paulo and Minas Gerais states, Brazil, that are extensively used for drinking in public places, bottling and bathing purposes, among other. The measurements of these alpha-emitting radionuclides were also accompanied by the monitoring of temperature and some dissolved gases (O2, CO2 and H2S) in 75 water sources located in 14 municipalities of those states. Eight water sources yielded 220Rn activity concentration values below the detection limit of 4 mBq/L. On other hand, 222Rn activity concentration values exceeding the WHO guidance level of 100 Bq/L in drinking-water for public water supplies were found in two springs, named Villela and Dona Beja, whose discharge occurs in areas characterized by the presence of enhanced levels of natural radioelements in rocks. The obtained results were compared with the guidelines of the Brazilian Code of Mineral Waters (BCMW) that was established in 1945 and is still in force in the country. The 222Rn and 220Rn activity concentration data allowed perform dose radiation calculations based on the potential alpha energy concentration (PAEC), whose implications for health risk have been also considered in this paper. - Highlights: • First thoron data in mineral waters occurring in well-known Brazilian spas. • Integration of thoron and radon data with those of others dissolved gases in mineral waters. • Comparison of the acquired data with the guidelines of the Brazilian Code of Mineral Waters. • Comparison of the radiation dose due to radon and thoron in the mineral waters

  5. 222Rn, 220Rn Concentrations and Miner Doses in Non-Uranium Mines in China

    A preliminary survey of 222Rn and 220Rn concentrations in non-uranium mines in China was conducted in 17 different types of mines. In total, 44 mines in 12 provinces were surveyed. The results showed that among 25 metal mines (n = 147) the arithmetic mean and geometric mean concentrations were 1214 ± 2358 and 313 ± 5.5 Bq/m3 for 222Rn, respectively (range 11–19 600 Bq/m3) and 268 ± 701 and 70 ± 4.4 Bq/m3 for 220Rn, respectively (range 220Rn, respectively (range 220Rn. The average dose in coal mines was 0.75 mSv, and in non-metal mines it was 0.38 mSv. (author)

  6. Dose ratio of 222Rn to 220Rn progeny in a pit using in-suit HPGe γ spectrometry

    To probe potential α energy concentration (PAEC) ratio and dose ratio of 222Rn to 220Rn progeny in a pit, in-situ HPGe γ spectrometry was used under atmospheric ventilation and without atmospheric ventilation conditions. The measurement data was analysed using relative efficiency method and PAEC method. The measurement results show that the average PAEC ratio and dose ratio of 222Rn to 220Rn progeny under without atmospheric ventilation is 3.6 and 10.8, respectively, which is 1.2 and 3.6 in first 8 hours under atmospheric ventilation. After 14 hours atmospheric ventilation, PAEC ratio and dose ratio are 0.2 and 0.6 stably. In-situ HPGe γ spectrometry has a great space in 222Rn and 220Rn dose research in the future. (authors)

  7. Research on factors influencing radon exhalation rate on aerated concrete block

    The research was carried out on the variation of the radon exhalation rate of aerated concrete block with the water content and dimension by using the RAD7 radon monitor and the radon exhalation rate test cabin of building materials. The result indicates that the amount of the same samples has no influence on the samples' radon exhalation; if the volume of the aerated concrete block in the test cabin is unchanged and the surface area increases, the radon exhalation rate decreases, but the total of the radon exhaling from the surface of the aerated concrete block keeps constant; for the aerated concrete block, its radon exhalation rate increases with water content as logarithmic growth. (authors)

  8. Radon exhalation rates from some building construction materials using SSNTDs

    Radon appears mainly by diffusion processes from the point of origin following α- decay of 226Ra in underground soil and building materials used. in the construction of floors, walls, and ceilings. In dwellings main source of radon are soil or rock underneath, building materials and portable water supplies. The major release of radon indoors is from building construction materials used. The radon measurements on the ground can give a clue about the hidden uranium. The exposure of population to high concentrations of radon and its daughters for a long period leads to pathological effects like the respiratory functional changes and the occurrence of lung cancer. In the present investigations radon exhalation rates from some soil and other building materials like fly ash, cement and sand collected from Panchkula, Ambala, Yamunanagar, Kurukshetra, Karnal and Panipat districts of Haryana have been estimated. For the measurement of radon concentration in these samples we used α-sensitive LR-115 type II plastic track detectors. The mass and the surface exhalation rates of radon emanated from these samples have also been calculated. The aim of study is the possible health risk assessment due to emission of radiation from building construction materials. (author)

  9. Natural radioactivity and radon specific exhalation rate of zircon sands

    Righi, S.; Verita, S.; Bruzzi, L. [Bologna Univ., Centro Interdipartimentale di Ricerca per le Scienze Ambientali and Dipt. di Fisica, Ravenna (Italy); Albertazzi, A. [Italian Ceramic Center, Bologna (Italy)

    2006-07-01

    The study focuses on the radon emanation from zircon sands and their derivatives, which are widely used in many sectors of industry. In particular, the results obtained by experimental measurements on samples of zircon sands and zircon flours commonly used in Italian ceramic industries are reported. Zircon sands contain a significant concentration of natural radioactivity because Th and U may substitute zirconium in the zircon crystal lattice. The relevant routes of exposure of workers to T.E.N.O.R.M. from zircon materials are external radiation and internal exposure, either by inhalation of aerosols in dusty working conditions or by inhalation of radon in workplaces. The main objective of this investigation is to provide experimental data able to better calculate the internal exposure of workers due to radon inhalation. Zircon samples were surveyed for natural radioactivity, radon specific exhalation rate and emanation fraction. Measurements of radioactivity concentration were carried out using {gamma}-spectrometry. Methods used for determining radon consisted in determining the {sup 222}Rn activity accumulated in a vessel after a given accumulation build-up time. The average activity concentrations of {sup 238}U and {sup 232}Th in samples result about 2600 and 550 Bq kg-1, respectively; these concentrations are significantly higher than the world average noticed in soils, rocks and Earth crust. The {sup 222}Rn specific exhalation rates result very low probably due to the low porosity of the material and the consequent difficulty for radon to be released from the zircon crystal lattice. (author)

  10. Natural radioactivity and radon specific exhalation rate of zircon sands

    The study focuses on the radon emanation from zircon sands and their derivatives, which are widely used in many sectors of industry. In particular, the results obtained by experimental measurements on samples of zircon sands and zircon flours commonly used in Italian ceramic industries are reported. Zircon sands contain a significant concentration of natural radioactivity because Th and U may substitute zirconium in the zircon crystal lattice. The relevant routes of exposure of workers to T.E.N.O.R.M. from zircon materials are external radiation and internal exposure, either by inhalation of aerosols in dusty working conditions or by inhalation of radon in workplaces. The main objective of this investigation is to provide experimental data able to better calculate the internal exposure of workers due to radon inhalation. Zircon samples were surveyed for natural radioactivity, radon specific exhalation rate and emanation fraction. Measurements of radioactivity concentration were carried out using γ-spectrometry. Methods used for determining radon consisted in determining the 222Rn activity accumulated in a vessel after a given accumulation build-up time. The average activity concentrations of 238U and 232Th in samples result about 2600 and 550 Bq kg-1, respectively; these concentrations are significantly higher than the world average noticed in soils, rocks and Earth crust. The 222Rn specific exhalation rates result very low probably due to the low porosity of the material and the consequent difficulty for radon to be released from the zircon crystal lattice. (author)

  11. Thoron (220Rn)-concentration in homes: first results of a pilot project

    First measurements of thoron gas concentrations in homes show that the indoor thoron concentration is less influenced by the thoron content in soil or by convective entry processes. The indoor concentration is dominated by thoron concentrations of building materials and by the surface layer of walls and floors. Measurements in typical indoor air without additional aerosol sources yield 212Pb size distributions with a media diameter of the accumulation mode of about 200 nm. An average fraction of 13% of the activity is associated with particles of the nuclei mode with diameters d between 10 - 100 nm and about 5% of the activity was determined to be unattached (d 212Pb)/C(220Rn) of 0.05 and C(212Bi)/C(212Pb) of 0.4. (orig.)

  12. The measurement of thoron (220Rn) concentration in indoor air continuously using pylon model WLx

    The concentration of thoron (220Rn) in particular location can be higher than radon (220Rn), however, its presence is always neglected. This might be due to the difficulties in calibration and discrimination between radon and thoron. From biokinetic and dosimetric model, it has been known that the dominant contribution of thoron to the effective dose is in the lungs. UNSCEAR estimates the doses contribution of thoron and its progenies is between 5-10% of the annual dose received by the general public and the risk level is 4.4 times greater than radon and progenies. Therefore, it is necessary to study the thoron concentration in indoor air and workplaces. Radon-thoron concentration in indoor air can be determined by direct methods using Pylon Model WLx device and passive methods using Solid State Nuclear Track Detector (SSNTDs). In this research the measurement of thoron was carried out continuously using Pylon Model WLx equipment that is sensitive to radon for 24, 65, 72, 116 and 154 hours in different rooms. The measurement result showed that the mean value of thoron working level (WL) concentration obtained in room-1 was 2.53 ± 0.67 Bq/m3 with maximum and minimum of thoron concentrations were 3.37 and 2.22 Bq/m3 respectively. From the measurement in different locations, it was obtained that the largest and smallest average concentrations of thoron progenies were 0.83 ± 0.23 Bq/m3 and 0.29 ± 0.64 Bq/m3, while the maximum and minimum concentration values were 7.80 Bq/m3 and 0.01 Bq/m3 respectively. Pylon Model WLx device is not enables to be used for longer and large scale survey area concurrently, so the SSNTDs which is sensitive to the emission of alpha particles and can measure cumulative thoron concentrations is required. (author)

  13. In situ measurements of radon and thoron exhalation rates and their geological interpretation

    Radon and thoron exhalation rates from the ground were measured at 23 sites in Tokyo and nine prefectures of Japan that were selected in consideration of geological features and soil distribution. The in situ measurements were carried out with a ZnS (Ag) scintillation detector equipped with a photomultiplier and a container measuring 30 x 40 cm and 11 cm in depth. The arithmetic means of radon and thoron exhalation rates were estimated to be 7.6 ± 2.6 mBq·m-2·s-1 and 0.69 ± 0.16 Bq·m-2·s-1, respectively. The exhalation rates differed up to 37-fold for radon and 265-fold for thoron between the maximum and minimum values, respectively. A geological interpretation suggests that the regional variations of the exhalation rates were mainly controlled by the source rock of the soil distributed around the measuring site. The correlation coefficient between the exhalation rate and SiO2 content of the rocks and soils distributed around the sites were estimated to be 0.99 for radon and 0.90 for thoron, respectively. Geological information is therefore considered to be a good indicator for estimating the exhalation rate. In addition, a correlation coefficient of 0.78 was accepted between the radon and thoron exhalation rates. This is considered to be useful information for making a rough estimation of one exhalation from the other. (author)

  14. Study of effect of addition of fly ash on radon exhalation rate in cement samples

    Most of the building materials like cement and fly ash contain naturally occurring radioactive materials (NORM). Increased interest in measuring radon exhalation rate in building products is due to the concern about health hazards of NORM. This paper focuses on studying the effect of addition of fly ash on radon exhalation rate in cement samples. Ordinary Portland Cement (OPC) and coal fly ash were used for finding the exhalation rate of cement in this paper. To study the effect on exhalation rate of cement, fly ash is added in different proportions to cement samples. The measurement was conducted by CAN Technique using SSNTDs. A gradual increase has been observed in radon exhalation rate up to certain proportion and then start to decrease. (author)

  15. Studying radon exhalation rates variability from phosphogypsum piles in the SW of Spain

    López-Coto, I., E-mail: israel.lopez@dfa.uhu.es [Dpto. Física Aplicada, Facultad CC. Experimentales, University of Huelva, Campus de El Carmen s/n, 21007 Huelva (Spain); Mas, J.L. [Dpto. Física Aplicada I. Escuela Politécnica Superior, University of Sevilla, C/Virgen de Africa 7, 41012 Sevilla (Spain); Vargas, A. [Universitat Politècnica de Catalunya, Instituto de Técnicas Energéticas, Campus Sud Edificio ETSEIB, Planta 0, Pabellón C, Av. Diagonal 647, 08028 Barcelona (Spain); Bolívar, J.P. [Dpto. Física Aplicada, Facultad CC. Experimentales, University of Huelva, Campus de El Carmen s/n, 21007 Huelva (Spain)

    2014-09-15

    Highlights: • Variability of radon exhalation rates from PG piles has been studied using numerical simulation supported by experimental data. • Most relevant parameters controlling the exhalation rate are radon potential and moisture saturation. • Piling up the waste increasing the height instead of the surface allows the reduction of the exhalation rate. • A proposed cover here is expected to allow exhalation rates reductions up to 95%. - Abstract: Nearly 1.0 × 10{sup 8} tonnes of phosphogypsum were accumulated during last 50 years on a 1200 ha disposal site near Huelva town (SW of Spain). Previous measurements of exhalation rates offered very variable values, in such a way that a worst case scenario could not be established. Here, new experimental data coupled to numerical simulations show that increasing the moisture contents or the temperature reduces the exhalation rate whilst increasing the radon potential or porosity has the contrary effect. Once the relative effects are compared, it can be drawn that the most relevant parameters controlling the exhalation rate are radon potential (product of emanation factor by {sup 226}Ra concentration) and moisture saturation of PG. From wastes management point of view, it can be concluded that piling up the waste increasing the height instead of the surface allows the reduction of the exhalation rate. Furthermore, a proposed cover here is expected to allow exhalation rates reductions up to 95%. We established that the worst case scenario corresponds to a situation of extremely dry winter. Under these conditions, the radon exhalation rate (0.508 Bq m{sup −2} s{sup −1}) would be below though close to the upper limit established by U.S.E.P.A. for inactive phopsphogypsum piles (0.722 Bq m{sup −2} s{sup −1})

  16. A simple model for automatically measuring radon exhalation rate from medium surface

    A simple model to measure radon exhalation rate from medium surface is developed in this paper. This model is based on a combination of the “accumulation chamber” technique and a radon monitor. The radon monitor is used to perform measurement of radon concentration evolution inside the accumulation chamber, and radon exhalation rate is evaluated via nonlinear least-square fitting of the measured data. If the flow rate of the pump is high enough, radon concentration in the detector's internal cell becomes to be equal to that in the accumulation chamber quickly, and the simple model for measuring the radon exhalation rate can be generated analytically. Generally, the pump flow rate of radon monitor is low, not satisfying the condition. We find other sufficient conditions of this simplified model. On these conditions, the radon exhalation rate can be calculated accurately through this model even the flow rate of the pump is not so high. This method can be applied to develop and improve the instruments for measuring the radon exhalation rate. - Highlights: • We present a novel simple model for measuring radon exhalation rate based on the complex model we published before. • The algorithm based on the simple model is developed. • The radon exhalation rate can be obtained by nonlinear least squares fitting. • The applicable condition of this simple model is obtained

  17. Investigation and analysis on seasonal variations of indoor 222Rn and 220Rn concentration in Longdong district, Gansu Province

    Objective: To study the seasonal variation of indoor 222Rn and 220Rn concentrations in Longdong district, Gansu Province. Methods: A total of 44 houses from 5 different types of raw soil architectures and 5 ordinary brick houses from a typical area were selected in Longdong district, Gansu Province in China. The LD-P discriminative 222Rn and 220Rn detectors were used to measure the indoor concentrations of 222Rn and 220Rn during four seasons in one year. Results: The indoor concentrations of 222Rn showed a significant seasonal variation,which varied with different types of houses. 222Rn concentrations of ordinary brick houses, soil brick houses and the cave dwellings were higher in winter and autumn and lower in summer. The average concentrations of 222Rn were 55.3-90.3 Bq/m3 in winter,36.4-65.7 Bq/m3 in spring, 35.6-63.9 Bq/m3 in summer, and 60.7-87.2 Bq/m3 in autumn. For cave dwellings,open-cut cave dwellings and the underground cave dwellings, 222Rn concentrations were higher in summer and autumn, and lower in winter and spring. The average concentrations of 222Rn ranged from 139-184 Bq/m3 in winter,135-199 Bq/m3 in spring, 179-252 Bq/m3 in summer,172-242 Bq/m3 in autumn. The seasonal variation of indoor 220Rn was basically consistent in six types of houses, and lower in winter and spring and highest in autumn. The average concentrations of 220Rn ranged from 43.4-64.3 Bq/m3 in winter, 60.6-537 Bq/m3 in spring, 77.7-792 Bq/m3 in summer, 63.2-1077 Bq/m3 in autumn. The indoor concentrations of 222Rn and 220Rn were different among different types of houses, and they were generally higher in type of raw soft architectures than in that of ordinary brick houses. Conclusions: 222Rn concentrations indoors showed a significant seasonal variation and varied with different types of houses. (authors)

  18. Do nuclei go pear-shaped? Coulomb excitation of 220Rn and 224Ra at REX-ISOLDE (CERN

    Scheck M.

    2015-01-01

    Full Text Available The IS475 collaboration conducted Coulomb-excitation experiments with post-accelerated radioactive 220Rn and 224Ra beams at the REX-ISOLDE facility. The beam particles (Ebeam: 2.83 MeV/u were Coulomb excited using 60Ni, 114Cd, and 120Sn scattering targets. De-excitation γ-rays were detected employing the Miniball array and scattered particles were detected in a silicon detector. Exploiting the Coulomb-excitation code GOSIA for each nucleus several matrix elements could be obtained from the measured γ-ray yields. The extracted ‹3−||E3||0+› matrix element allows for the conclusion that, while 220Rn represents an octupole vibrational system, 224Ra has already substantial octupole correlations in its ground state. This finding has implications for the search of CP-violating Schiff moments in the atomic systems of the adjacent odd-mass nuclei.

  19. Effect of moisture on radon exhalation rate of the building material bricks

    In the paper, The moisture of building material bricks was controlled by the saturation solution of inorganic salt which were deposited in a obturator. The activated charcoal method was used to compare the influence of radon exhalation rate of building material bricks on different moistures condition. From the result, it can be found that with the increasing of mositure, the radon exhalation rate is increasing at first and then discreasing, when the mositure is about 4%, and the highest radon exhalation rate is 32.31 ± 2.84mBq. m-2.s-1. (authors)

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

    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.

  1. Estimation of 222Rn, 220Rn and their progeny concentration using pin-hole cup dosimeters and deposition based progeny sensors

    Radon (220Rn) and Thoron (220Rn) progeny concentrations contribute to the natural radiation dose to general public. Due to the fact that the inhalation doses due to 222Rn and 220Rn are contributed predominantly by their decay products, development of passive techniques for monitoring the decay products directly assumes considerable significance. The concentrations of progenies are determined through Equivalent Equilibrium Concentrations of 222Rn as well as 220Rn (EERC and EETC) respectively. EERC and EETC are measured by deposition based Direct Progeny Sensors (DRPS, DTPS) in bare modes. Direct Thoron Progeny Sensors (DTPS) and Direct Radon Progeny Sensors (DRPS) are developed which are depositions based systems and hence ensure that they respond only to the decay products and not to gas concentrations. The recently developed (by BARC) DRPS and DTPS technique for 222Rn and 222Rn progeny measurements for the present study will be better than previous available techniques viz. use of SSNTDs in bare and cup mode

  2. Estimation of the radon dose in buildings by measuring the exhalation rate from building materials

    We review the accumulator technique using active (CRM) and passive detectors (activated charcoal and electret). We describe the ERS2 detector, an electrostatic radon sampler followed by alpha spectrometry, with improved algorithm and adapted to measure the exhalation rate from walls. The technique produces accurate results over a broad range of materials: concrete, Pumice, ceramics, tiles, granite, etc. The measured exhalation rate is the same, within errors, as measured by the standard detectors

  3. Radon exhalation rates of concrete modified with fly ash and silica fumes

    The radiological impact of the environmental gas radon to the health of general public is of concern since many decades. Cement used for the construction blended with fly ash and silica fumes is recommended by Government in order to avoid the soil and environmental pollution. But these addition step-up the Indoor radon level in the dwelling due to radioactivity contents. The exhalation of radon from concrete blended with silica fumes and fly ash depends upon addition level, porosity, moisture and radioactivity content. In order to optimize the level of substitution of silica fumes and fly ash, measurements of radon exhalation rates from the concrete blended with different proportions of fly ash and silica fumes was carried out using active scintillation radon monitor. The effect of porosity, moisture, back diffusion and radioactivity content of the concrete on exhalation rates is studied. The measured exhalation rates were extrapolated for indoor radon concentration and effective dose equivalent using ICRP, 1987 recommendations. (author)

  4. Measurement of radium concentration and radon exhalation rate in building material samples

    Building materials are the main source of radon in the dwellings. Therefore measurement of radon exhalation rate from these materials will help in the prediction of existence of dwelling with potential radon risk. Radon exhalation rate from building materials varies with type and origin. Emanation of radon is associated with the presence of radium and its ultimate precursor uranium in the ground. Solid state nuclear track detectors (LR-115 TYPE-II) are used to determine radon exhalation rate in building material samples collected from the different locations of Himachal Pradesh. SSNTD mainly detects the alpha particles having energy ranging from 1.7 to 4.8 MeV. For this purpose, building materials are collected in plastic can containing LR-115 TYPE-II solid state nuclear track detectors which are very sensitive for alpha particles. The samples are granite, marble and sandstone. There is a large variation in values of radon exhalation rate which may be due to the difference in radium content. The exhalation rate for the measured samples varies from 40.72 mBqkg-1h-1(sandstone) to 81.40 mBqkg-1h-1(granite). From the results, it is clear that granite sample shows higher radon exhalation rate than that of marble and sandstone samples. The emanation coefficient and effective alpha dose equivalent is also calculated for the health risk assessment. (author)

  5. Fractal analysis of spatial distribution of radon exhalation rates of uranium mill tailings

    A uranium mill tailings, located in Guangdong, was selected for spatial distribution of the radon exhalation rates measured by local static method. The two-dimension surface of radon exhalation rates was established by Surfer using the data of spatial distribution of radon exhalation rates measured at August 14, 2007 to 19 and 21, which was analyzed by fractal method of projective covering. The results show that the two-dimension surface of radon exhalation rates is of fractal structure. The fractal dimension of surface of radon exhalation rates from August 14, 2007 to 19 and 21 are 2.0535, 2.0173, 2.0029, 2.0084, 2.0079, 2.0057 and 2.0034, respectively, which indicates that the complexity of spatial distribution of the radon exhalation rates at 14 and 15 are larger than that of the other days. The phenomenon results from the change of precipitation and temperature, as well as the features of uranium mill tailings, including mineral composition, particle size, radium content, porosity and pore connectivity, etc. (authors)

  6. Natural radioactivity and radon exhalation rate in Brazilian igneous rocks

    Moura, C.L.; Artur, A.C. [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil); Bonotto, D.M., E-mail: danielbonotto@yahoo.com.b [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil); Guedes, S. [Departamento de Cronologia e Raios Cosmicos, Instituto de Fisica Gleb Wataghin, Universidade Estadual de Campinas (UNICAMP), Rua Sergio Buarque de Holanda No. 777, CEP 13083-859, Campinas, Sao Paulo (Brazil); Martinelli, C.D. [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil)

    2011-07-15

    This paper reports the natural radioactivity of Brazilian igneous rocks that are used as dimension stones, following the trend of other studies on the evaluation of the risks to the human health caused by the rocks radioactivity as a consequence of their use as cover indoors. Gamma-ray spectrometry has been utilized to determine the {sup 40}K, {sup 226}Ra and {sup 232}Th activity concentrations in 14 rock types collected at different quarries. The following activity concentration range was found: 12.18-251.90 Bq/kg for {sup 226}Ra, 9.55-347.47 Bq/kg for {sup 232}Th and 407.5-1615.0 Bq/kg for {sup 40}K. Such data were used to estimate Ra{sub eq}, H{sub ex} and I{sub {gamma}}, which were compared with the threshold limit values recommended in literature. They have been exceeded for Ra{sub eq} and H{sub ex} in five samples, where the highest indices corresponded to a rock that suffered a process of ductile-brittle deformation that caused it a microbrecciated shape. The exhalation rate of Rn and daughters has also been determined in slabs consisting of rock pieces {approx}10 cm-long, 5 cm-wide and 3 cm-thick. It ranged from 0.24 to 3.93 Bq/m{sup 2}/h and exhibited significant correlation with eU (={sup 226}Ra), as expected. The results indicated that most of the studied rocks did not present risk to human health and may be used indoors, even with low ventilation. On the other hand, igneous rocks that yielded indices above the threshold limit values recommended in literature may be used outdoors without any restriction or indoors with ample ventilation.

  7. A comparative study between the dynamic method and passive can technique of radon exhalation measurements from samples

    A comparative study has been carried out between the SSNTD based ‘can’ technique and active monitors based dynamic method using nine different samples, eight of granite and one of phosphogypsum. Besides radon (222Rn) exhalation, thoron(220Rn) exhalation and 226Ra and 232Th content were also measured. The results are: (i) presence of significant thoron exhalation from samples and (ii) observation of thoron interference and leak (~0.05 h−1) from the ‘can’ in the SSNTD based ‘can’ technqiue. The study unequivocally demonstrates the presence of intrinsic uncertainty in SSNTD based ‘can’ technique. Instead, dynamic method offers a more reliable and faster method. - Highlights: • Comparative study has been carried out between active and SSNTD based ‘can’ techniques. • Study showed large difference in measured radon and thoron exhalation rates. • Study unequivocally demonstrates the presence of intrinsic uncertainty in SSNTD based ‘can’ technique. • The uncertainty has been analyzed through thoron interference and leak effect

  8. Measurement of radon/thoron exhalation rates and gamma-ray dose rate in granite areas in japan

    Radon and thoron exhalation rates and gamma-ray dose rate in different places in Hiroshima Prefecture were measured Exhalation rates were measured using an accumulation chamber method. The radon exhalation rate was found to vary from 3 to 37 mBq m-2 s-1, while the thoron exhalation rate ranged from 40 to 3330 mBq m-2 s-1). The highest radon exhalation rat(37 mBq m-2 s-1) and gamma-ray dose rate (92 nGy hs-1, were found in the same city (Kure City). In Kure City, indoor radon and thoron concentrations were previously measured at nine selected houses using a radon-thoron discriminative detector (Raduet). The indoor radon concentrations varied from 16 to 78 Bq m-3, which was higher than the average value in Japan (15.5 Bq m-3). The indoor thoron concentration ranged from ND (not detected: below a detection limit of approximately 10 Bq m-3) to 314 Bq m-3. The results suggest that radon exhalation rate from the ground is an influential factor for indoor radon concentration. (authors)

  9. The influence of thoron on measurement results of radon exhalation rate

    Xiao De Tao; Ling Qiu; Leung, J K C

    2002-01-01

    Because of thoron exhalation, the measurement results of radon exhalation rate using a local still method is usually larger than the true value of radon flux rate of the monitored material surface. The influence of sup 2 sup 1 sup 6 Po(ThA) on radon exhalation rate can be eliminated for sensitive radon monitors. Theoretical evaluations of the influence of sup 2 sup 1 sup 2 Bi(ThC) and sup 2 sup 1 sup 2 Po(ThC')on radon exhalation rate are carried out in a sampler with diameter of 188 mm, and height of 125 mm, and supplied electrostatic field inside (generated by high voltage and electret) under following conditions: the sampling time are 1, 2, 3 h, respectively, thoron exhalation rate is 100 times of radon's. The calculation results indicate that the measurement results of radon flux rate are possibly 35.5% larger than true value due to the influence of thoron for fast and multifunctional radon monitors with electret, high voltage, respectively and using CR-39 SSNTD as detector, but this influence is negligib...

  10. Measurement of radon exhalation rate in some industries residue used in new type wall materials

    Objective: To study the radon exhalation rate in some industries residue used in new type wall materials. Methods: To determine the radon exhalation rate by the activated charcoal absorption and γ-ray spectrometer with HPGe detector. Results: The radon exhalation rate level is successively autoclaved aerated concrete block (9.70 ± 2.54 Bq·m-2·s-1, fly ash block (5.83 ± 1.85) Bq·m-2·s-1, gangue block (4.70±2.45) Bq·m-2·-1, clay block (2.63 ± 0.56) Bq·m-2·s-1. Conclusion: The average radon exhalation rate level of autoclaved aerated concrete block and fly ash block is significantly higher than that 1 of clay block, the differences is significant (P0.05). The gangue block is a ideal New Type Wall Material, whose radon exhalation is lower than that of autoclaved aerated concrete block and fly ash block. (authors)

  11. Indoor radon levels and their relationship with radon exhalation rates from building surface in Hong Kong

    The indoor radon concentrations of more than 60 sites in Hong Kong is measured using activated charcoal canisters to identify the underlying distribution pattern. The strong relationship between the indoor radon concentrations and the radon exhalation rate from building surface has been investigated. It has been found that the indoor radon comes mainly from radium in building materials, and that the radon concentration depends on the radon exhalation rate from indoor building surface and on the ventilation. It is also asserted that the radioactivity level of building materials used in Hong Kong is increasing

  12. A correlation study between indoor radon-thoron concentration and soil exhalation rates from Indian dwellings

    The measurements of indoor radon and thoron concentration in some north Indian dwellings were carried out using pin hole based radon thoron dosimeters. The inhalation doses were calculated by ICRP recommendations. The radon and thoron exhalation rates from the soil collected from the same dwellings area were also carried out with closed chamber technique using active measurement by scintillation radon monitor and scintillation thoron monitor. The indoor radon and thoron concentration varied from 12 to 90 Bq/m3 and 20 to 140 Bq/m3 respectively. A good positive correlation was found between indoor radon thoron concentration and their exhalation rates. (author)

  13. Determination of Radon Exhalation Rate From Building Material Using Passive Method With Nuclear Track Detector

    Passive method with Cr-39 nuclear track detector has been developed for the measurement of radon exhalation rate from building material with accuracy of 4% and reproducibility between 6-9%. The procedure is simple and applicable for using in field. For routine use, minimum detectable level of 0.026 Bq/m2 hour, if exposure time is 21 days. Based on preliminary study, radon exhalation rate around between 0.80 and 1.32 Bq/m2 hour, higher on white batako and lowest on light concentrate. Application of surface coating (plastering and latex paint), can reducing flux radon among 38 to 72 %

  14. Natural Radioactivity and 222Rn Exhalation Rate from Brazilian Phosphogypsum Building Materials

    Phosphogypsum is classified as a NORM residue and one of the main environmental concerns of its use is the radon exhalation from this material. The aim of this study is to determine the activity concentration of natural radionuclides, radium equivalent activities, external and internal hazard index and the radon exhalation rate from bricks and plates made of phosphogypsum. The activity concentration and radon exhalation rate were in accordance with literature values. The results of radium equivalent, external and internal hazard index showed that plates and bricks from Ultrafertil and Fosfertil presented values above the recommended limits; indicating the necessity of using more realistic models for the safe application of phosphogypsum as building materials. The results of this study can contribute for the establishment of guidelines by the Brazilian regulatory agency, for the safe use of phosphogypsum as building material. (author)

  15. Evaluation of dose arising from 222Rn, decay products of 222Rn and 220Rn to staff from a certain nuclear power plant

    The staff of the plant was grouped on their work ranges. The annual effective dose resulted from radon and the decay products of 222Rn/220Rn is studied by measuring radon concentration with double filter membrane method and by measuring the concentration of 222Rn/220Rn short life radioactive decay products with five-count method. Based on the results, specific protection measures are proposed for high radon areas. The study results show that the monitoring data for all areas except the spent fuel pool was smaller than the recommended values by ICRP. (authors)

  16. Environmental impact of radon exhalation rates and radio activity from various commodities: a review

    This study presents a review report of radon exhalation rate and natural radioactivity from various commodities such as fly ash of thermal power plants, soil, radiation shielding material etc. The perspective radiation shielding materials using fly ash and other commonly used construction have also been tested for the presence of natural radioactivity

  17. Primary investigation and study on 222Rn and 220Rn levels of underground coal mines in China

    From Dec. of 2002 to Aug. of 2004, by using Solid State Nuclear Track Detectors (SSNTDs), the 222Rn concentrations of 8 underground coal mines, i.e., Beijing Shijiaying, Beijing Fangshanchengguan, Shanxi Gujiaoxiqu, Shanxi Taiyuan Wangfang, Hunan Baifang, Hunan Songbai, Guizhou Honglin and Zhejiang Anrenjinjiang, Respectively, had been measured during a period of 12 months (once a three-month). The surveyed data showed that the annual average 222Rn concentrations (with number of measuring points) are 550(69), 3187(28), 45(224), 117(72), 88(79), 79(58), 40(72) and 136(116) Bq/m3, respectively. The 222Rn concentrations of underground coal mines vary with ventilation condition, geological structure and other factors, and the 222Rn concentration in the mine with bad ventilation is generally high, and varies with seasons i.e., higher in summer and autumn and lower in winter. The 222Rn concentration in mines with good ventilation is generally low and no notable variation with the season. These are also some characters of 222Rn levels in Chinese coal mines, such as the 222Rn concentrations in state-run coal mines are general low, but those in Beijing area are very high, and those in Zhejiang rock coal mines are not so high as expected, etc., the possible reasons have been discussed in the paper. The 220Rn levels of 4 coal mines in Beijing and Hunan were also measured, the ratios of alpha potential energy concentration of 220Rn daughters to that of 222Rn daughters are between 0.036 and 0.42. (authors)

  18. Evaluation of Radon-222 exhalation rate from uranium mine waste rock pile

    The 222 Rn exhalation from waste rock piles is an important item to be assessed in uranium mines decommissioning process. In this work are presented the INB-Caldas Uranium Mine waste rock pile number 4 (BF4) surface 222 Rn exhalation rate. The BF4 waste rock pile contains low concentration uranium ore, below the concentration needed to feed the uranium extraction milling plant, and its surface has been partially covered with clay to prevent acid drainage formation from air oxygen reaction with pyrite ore. The sample collection was performed using passive coal trap collectors for 222 Rn exhalation. The traps were placed on the waste rock pile surface during adequate collection periods and gamma counted after four hours to allow for radon daughters in growth. The waste rock pile (BF4) has been divided into five areas, according to mining periods. Measurements were made in three of these areas, during dry and rain seasons, 141 samples in all. The 222 Rn exhalation geometric mean (pCi/m-2.sec-1) obtained by area were 21.8±253 (min=0..6, max =1809) for area A; 11.9±33 (min=0.5, max=160) for area B; 6.6±11 (min=0.6, max=47) for area D. (author)

  19. Measurement of Radon Exhalation Rate in Sand Samples from Gopalpur and Rushikulya Beach Orissa, Eastern India

    Mahur, Ajay Kumar; Sharma, Anil; Sonkawade, R. G.; Sengupta, D.; Sharma, A. C.; Prasad, Rajendra

    Natural radioactivity is wide spread in the earth's environment and exists in various geological formations like soils, rocks, water and sand etc. The measurement of activities of naturally occurring radionuclides 226Ra, 232Th and 40K is important for the estimation of radiation risk and has been the subject of interest of research scientists all over the world. Building construction materials and soil beneath the house are the main sources of radon inside the dwellings. Radon exhalation rate from building materials like, cement, sand and concrete etc. is a major source of radiation to the habitants. In the present studies radon exhalation rates in sand samples collected from Gopalpur and Rushikulya beach placer deposit in Orissa are measured by using "Sealed Can technique" with LR-115 type II nuclear track detectors. In Samples from Rushikulya beach show radon activities varying from 389 ± 24 to 997 ± 38 Bq m-3 with an average value of 549 ±28 Bq m-3. Surface exhalation rates in these samples are found to vary from 140 ± 9 to 359 ± 14 mBq m-2 h-1with an average value of 197 ±10 mBq m-2 h-1, whereas, mass exhalation rates vary from 5 ± 0.3 to 14 ± 0.5 mBq kg-1 h-1 with an average value of 8 ± 0.4 mBq kg-1 h-1. Samples from Gopalpur radon activities are found to vary from 371 ± 23 to 800 ± 34 Bq m-3 with an average value of 549 ± 28 Bq m-3. Surface exhalation rates in these samples are found to vary from 133 ± 8 to 288 ± 12 mBq m-2h-1 with an average value of 197 ± 10 mBq m-2 h-1, whereas, mass exhalation rates vary from 5 ± 0.3 to 11 ± 1 mBq kg-1 h-1 with an average value of 8 ± 0.4 mBq kg-1 h-1.

  20. A note on "an erroneous formula in use for estimating radon exhalation rates from samples using sealed can technique".

    Mayya, Y S; Sahoo, B K

    2016-05-01

    In this note, we point out a serious fallacy in a formula that has appeared in literature for calculating the (222)Rn exhalation rates using the Solid-State Nuclear Track Detector (SSNTD) based sealed can technique. It is shown that this formula underestimates true exhalation rates by a factor of more than 10(6). Several publications have used this formula instead of the well-known Abu-Jarad formula and have reported unrealistically low (µBq/m(2)/d) surface exhalation rates for normal materials. PMID:26896680

  1. Measurement of radon exhalation rates in some soil samples collected from Western Haryana

    Indoor radon has been recognized as one of the health hazards for mankind. Common building materials used for construction of houses are considered as major sources of radon gas in indoor environment. In the present work, the radon exhalation rates were measured using 'Canister' technique. The alpha sensitive solid state nuclear track detector (LR-115 type-II) were used in the canisters for recording tracks produced by alpha particles from radon gas emanated from building materials. The samples of soil, were collected from Western districts of Haryana, India. The detectors were exposed in the canisters for 100 days. After the exposure time the detectors were etched using 2.5 N NaOH solution at 60℃ for 1.5 hours. The track density was found using an optical microscope at a magnification 600X. The mass and surface exhalation rates are also calculated from the data. (author)

  2. Modelling radiation exposure in homes from siporex blocks by using exhalation rates of radon

    Nikolić Mladen D.

    2015-01-01

    Full Text Available Building materials are the second major source of indoor radon, after soil. The contribution of building materials to indoor radon amount depends upon the radium content and exhalation rates, which can be used as a primary index for radon levels in the dwellings. This paper presents the results of using the experimentally determined exhalation rates of siporex blocks and concrete plates, to assess the radiation exposure in dwellings built of siporex blocks. The annual doses in rooms have been estimated depending on the established modes of ventilation. Realistic scenario was created to predict an annual effective dose for an old person, a housewife, a student, and an employed tenant, who live in the same apartment, spending different periods of time in it. The results indicate the crucial importance of good ventilation of the living space.

  3. Radon exhalation rates and effective radium contents of the soil samples in Adapazarı, Turkey

    Kuş, Adem; Yakut, Hakan; Tabar, Emre

    2016-03-01

    In this study effective radium content and radon exhalation rates in soil samples collected from Adapazarı district of Sakarya, Turkey have been measured using LR-115 type-II plastic track detectors by closed-can technique for the first time. The obtained effective radium contents are found to vary from 6.66 to 34.32 Bqkg-1 with a mean value of 18.01 Bqkg-1. The radon exhalation rates measured in terms of mass and area of soil samples are found to vary from 50.35-259.41 mBqkg-1h-1 with a mean value of 136.12 mBqkg-1h-1 and 1035.18-5333.39 mBqm-2h-1 with a mean value of mBqm-2h-1. All the measurements show that the values of radium content are under the safe limit recommended by Organization for Cooperation and Development.

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

    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

  5. Measurement of radon exhalation rates, natural environmental radioactivity and radiation exposure from Indian commercial granites

    Uranium is a radiotoxic element found in trace quantities in almost all naturally occurring materials like soil, rocks, and sand etc. Building materials are derived from these materials and are the main source of radon inside the dwellings. Several varieties of granites are produced and used as flooring materials and as ornamental stones in buildings in India. Commercial type of granites with specific names corresponds to geographical and geological origins and mineral compositions. The natural radioactivity present in rocks having high radiation levels are associated with granites. Measurement of radon exhalation rates for granite samples were carried out through sealed can technique using -115 type II detectors. Wide variation in radon exhalation rates is found in the samples. Radon activity is found to vary from 380.0 to 4258.6 Bq m-3 with an average value of 1316.2 m-3, whereas radon exhalation rate varies from 227.4 to 2548.8m Bq m-2 h-1 with an average value of 854.7 m Bq m-2 h-1. The variation can be correlated with the color of the granites. Effective dose equivalent, estimated from exhalation rate varies from 26.8 to 300.6 Sv y-1 with an average value of 100.8 Sv y-1. Activity concentrations of naturally occurring radionuclides (226Ra, 232Th and 40K) were also measured in these samples using high resolution γ-ray spectroscopic system. Gamma spectrometric measurements were carried out at Inter-University Accelerator Centre, New Delhi using a coaxial n-type HPGe detector (EG and G, ORTEC, Oak Ridge, USA). The detector has a resolution of 2.0 keV at 1332 keV and relative efficiency of 20%. It was placed in 4 inch shield of lead bricks on all sides to reduce the background radiation from building materials and cosmic rays

  6. Measurement of radon activity and exhalation rate in soil samples from Banda district, India

    Radon activities and radon exhalation rates have been measured in soil samples collected from different location of Banda district of Uttar Pradesh in India using LR-115 type II solid state nuclear track detectors. Radon activity has been found to vary from (101.0) to (505.1) Bq/m3 with an average value of (278.3) Bq/m3. Surface exhalation rate has been found to vary from (84.0) to (419.8) mBq/m2/h with an average value (231.3) mBq/m2/h, whereas mass exhalation rate has been found to vary from (2.1) mBq/kg/h to (10.6) mBq/kg/h with an average value of (5.8) mBq/kg/h. Effective dose from indoor inhalation exposure (radon) has been estimated, which is found to vary from (6.1) to (30.5) μSv/year with an average value of (16.8) μSv/year. (author)

  7. Measurement of radon exhalation rate from fly ash samples generated in some major thermal power stations

    Coal-fired thermal power stations account for a majority of the electricity produced in India (about 70%). The coal used in thermal power stations have as high as 35 to 40% ash content resulting in generation of huge quantities of fly ash, a waste product product produced due to the burning of coal. The ever-increasing demand for electricity necessitates the need for the productive utilization of fly ash. One of the areas of major areas of utilization is mixing of fly ash in cement and bricks used for construction of dwellings and office premises. There has been apprehension among the public and environmentalists on the use of fly ash as it contains trace quantities of naturally occurring radioactive materials. Fly ash samples from some of the major thermal power stations across the country were collected and the radon exhalation rates were estimated experimentally using 'can' technique. This technique is a simple and widely-used method for the estimation of exhalation rate measurements. 50 grams fly ash samples were placed in a petri-dish. LR-115 film was affixed at the bottom of the lid of the petri-dish and sealed. Radon gas was allowed to accumulate in the dish for a period of one month, at the end of which the films were retrieved and processed. The radon exhalation rate from the samples analyzed varied between 0.01 and 0.05 Bq kg-1h-1. (author)

  8. Radon exhalation rate from the soil, sand and brick samples collected from NWFP and FATA (Pakistan))

    In order to characterise the building materials as an indoor radon source, knowledge of the radon exhalation rate from these materials is very important. In this regard, soil, sand and brick samples were collected from different places of the North West Frontier Province (NWFP) and Federally Administered Tribal Areas (FATA) (Pakistan)). The samples were processed and placed in plastic containers. NRPB radon dosemeters were installed in it at heights of 25 cm above the surface of the samples and containers were then hermetically sealed. After 40-80 d of exposure to radon, CR-39 detectors were removed from the dosemeter holders and etched in 25% NaOH at 80 deg. C for 16 h. From the measured radon concentration values, 222Rn exhalation rates were determined. Exhalation rate form soil, sand and brick samples was found to vary from 114 ± 11 to 416 ± 9 mBq m-2 h-1, 205 ± 16 to 291 ± 13 mBq m-2 h-1 and 245 ± 12 to 365 ± 11 mBq m-2 h-1, respectively. (authors)

  9. Estimation of radon exhalation rate in Gopalpur beach sand samples Orissa, Eastern India

    In the present studies radon exhalation rates in sand samples collected from Gopalpur beach placer deposit in Orissa are measured by using 'Sealed can technique' using type LR 115-II nuclear track detectors. Radon activities are found to vary from 371.4 ± 23.0 to 800.0 ± 33.8 Bqm-3 with an average value of 549.2 ± 27.8 Bqm-3. Surface exhalation rates in these samples are found to vary from 133.4 ± 8.3 to 287.7 ± 12.1 mBqm-2h-1 with an average value of 197.2 ± 9.9 mBqm-2h-1, whereas, mass exhalation rates vary from 5.1 ± 0.3 to 11.1 ± 0.5 mBqkg-1h-1 with an average of 7.6 ± 0.4 mBqkg-1h-1. (author)

  10. Active measurement of radon and thoron exhalation from soil and building materials samples and effect of grain size

    Radon (222Rn) and Thoron (220Rn) emission from soil and building materials is considered as primary sources for inhalation dose to a person in indoor environment. In view of this, experiments have been carried out to determine radon and thoron emission from samples of soil and building materials using BARC developed smart radon and thoron monitor. Samples that were subjected to analysis included soil, sand, cement, flyash, POP, snewcem, lime powder, chalk putty and wallputty. Each sample was kept in a leak tight metal chamber, connected to a radon/thoron monitor to measure radon and thoron concentration at different time interval. Thoron being short-lived (half life of 55.6 s), a minimum thickness of building material was maintained such that the thoron surface exhalation rate will be independent of sample size. In case of radon, the air volume of the set up was kept sufficient enough to neglect the possible back diffusion effect. The influence of grain size on radon and thoron exhalation rates in soil and fly ash samples has been investigated by measuring the packing density and % porosity of samples. (author)

  11. Development of a PIN diode based on-line measurement system for Radon (222Rn) and Thoron (220Rn) in environment

    Radon, thoron and their progenies are universally present in outdoor air, and can reach higher levels in indoor air due to poor ventilation. Several instruments have been developed for accurate measurement of radon and thoron in the environment. Semiconductor detector based system employing spectroscopic method has been proved to be the best among them. A PIN diode based electrostatic collection type online real-time instrument has been developed in Bhabha Atomic Research Centre for simultaneous measurement of radon and thoron in an environment while both 222Rn and 220Rn are present. This system can be used for determination of radon and thoron concentrations at residence or workplace. Furthermore, since the 222Rn and 220Rn are differentiated from each other through spectroscopy, this monitor can be used even in a mixed radon/thoron environment

  12. Development of a PIN diode-based on-line measurement system for radon (222Rn) and thoron (220Rn) in the environment

    A silicon PIN diode-based electrostatic collection type online real-time instrument has been developed for simultaneous measurement of radon (222Rn) and thoron (220Rn). The system, discussed in this paper, utilizes a hemispherical metal chamber (volume 1 L) for active air sampling. Estimation of 222Rn/220Rn concentration is carried out through alpha spectroscopy of electro-deposited polonium atoms on the detector surface. The system description and the characterization studies carried out with this instrument are presented here. Its performance has been tested with reference equipments. The instrument showed sensitivity of 0.408 counts per hour (CPH)/(Bq/m3) and 0.169 CPH/(Bq/m3) for radon and thoron measurements, respectively, at an optimized collection voltage of + 1.6 kV and relative humidity <10%. (author)

  13. Continuous on-line calibration of diffusive soil-atmosphere trace gas transport using vertical 220Rn- and 222Rn-activity profiles

    Continuous monitoring of 220Rn- and 222Rn-activities above and below the soil surface combined with sporadic direct 222Rn-flux measurements is used to quantify diffusive trace gas transport in the air-filled pore space of soil, through the soil-atmosphere interface and in the lowest layers of the atmosphere. In a calm night, 222Rn-activities above the surface first build-up near the ground (z 222Rn-flux from activity profiles measured in soil gas, (2) from direct flux determinations and (3) using information about atmospheric diffusion parameters from 220Rn-activities measured near the surface it is possible to model the temporal evolution of the vertical 222Rn-profiles in a night with stable weather and constant soil conditions. The system operates automatically for extended periods of time in the field enabling a better understanding of transport processes in response to changing environmental conditions (wind, rain, soil humidity). (orig.)

  14. Radium and radon exhalation rate in soil samples of Hassan District of South Karnataka

    Radon is present in both indoor and outdoor air due to the decay of 226Ra, which is present everywhere in the Earth's crust with varying concentration. Among many factors affecting radon exhalation, one of the most important is radium content of the bed rock or soil. Higher values of 226Ra in soil contribute significantly in the enhancement of environmental radon. Radon has a half-life of 3.82 days and it is chemically inert. Radon gas from soil is considered to be the most important source and it enters house mainly through cracks in the building structure. Radon and its daughter products are the major sources of radiation exposure and are recognized as one of the health hazard for mankind. In view of this, studies on the radon have assumed great significance worldwide. In the present work, an attempt was made to assess the radon exhalation rate in the environment of Hassan district of south Karnataka. Radon exhalation rate was determined by 'sealed can technique' using alpha sensitive solid state nuclear track detectors (LR-115 Type-II). The exposed films were etched with 2.5 N NaOH solution for 60 min at 60°C. The activity was counted using Spark Counter. Radon activity was found to vary from 19.3 ± 5.8 Bq m-3 to 224.0±31.5 Bq m-3 and radium equivalent activity varied from 103.4 ± 31.4 mBq kg-1 to 1198.7±16.8 mBq kg-1. Surface exhalation rate of radon vary from 13.3 ± 5.2 mBq m-2 h-1 to 154.2 ± 26.3 mBq m-2 h-1 and mass exhalation rate of radon vary from 2.7 ± 0.8 mBq kg-1 h-1 to 30.9 ± 4.36 mBq kg-1 h-1. The results of this systematic investigation are presented and discussed in the paper. (author)

  15. Dynamics, deterministic nature and correlations of outdoor 222Rn and 220Rn progeny concentrations measured at Bacau, Romania

    The long-term variation, nature and correlations of outdoor 222Rn and 220Rn progeny concentrations measured during the period 1994-2009 were investigated. The time series of data were obtained within the framework of the monitoring program performed by the Environmental Radioactivity Monitoring Station (ERMS) Bacau, a component part of the National Environmental Radioactivity Survey Network (NERSN), coordinated by National Environmental Protection Agency (NEPA). The measuring method is based on the total beta measurements of atmospheric aerosol filters, using a low background total beta counter and (90Sr/Y) reference standard. Analysis of the time series of progeny concentrations in the low atmosphere makes evident different patterns of variation of these concentrations: diurnal, seasonal and annual. A possible relationship of progeny concentration increase with global warming is emphasized. In order to find the dominant frequency of the physical processes determining progeny concentration variability the power spectrum has been used. The deterministic nature of the time series of concentrations has been studied making use of the autocorrelation function and stationarity of the original data and of their phase randomized time series. Also, the correlations with meteorological parameters have been investigated using Pearson's correlation coefficient with corresponding level of significance. - Highlights: → Radon and thoron progeny concentrations measured on a period of 16 years. → 5 h, daily, monthly and annual patterns are pointed out. → Autocorrelation functions prove non-randomness of concentrations. → Deterministic nature of time series of concentrations is demonstrated. → Correlations with meteorological data are studied.

  16. Radon exhalation rate from the building materials of Tiruchirappalli district (Tamil Nadu State, India)

    Tiruchirappalli district has enriched resources of building materials such as stone, granite, sand, brick, cement, etc., which are also supplied to the neighbouring districts. Since radon is considered as one of the causative factors for human lung diseases, the measurement of the radon level in these building materials is imperative for the assessment. The samples of building materials were collected from their original sources spread over Tiruchirappalli district. The sealed can technique with solid state nuclear track detector (SSNTD) was employed for the measurement of radon exhalation. The activity concentrations of radon in sedimentary rocks analyzed ranged from 13.2 Bq/m3 to 218.0 Bq/m3 with the geometric mean activity of 46.3 Bq/m3. However, radon concentrations in igneous rocks are distinctly higher than those of sedimentary rocks and ranged from 95.6 Bq/m3 to 1140 Bq/m3 with the geometric mean activity concentration of 392.6 Bq/m3. The radon exhalation from sand, brick, and cement were found to be non-uniform (sand: 119.8-656 Bq/m3, brick: 31-558 Bq/m3, cement: 172-300 Bq/m3). The activity concentration of radon in these building materials follow a descending order: Granite > sand > cement > brick > sand stone. The mass and surface exhalation (EM and EA) rates also follow the same order. The study concludes that since the radon exhalation from the building materials was less than the International Commission on Radiological Protection limit of 1500 Bq/m3, they do not pose any radiological risk. (author)

  17. Effect of moisture on the radon exhalation rate from soil, sand and brick samples collected from NWFP and FATA (Pakistan))

    A series of experiments were carried out to study the effect of the moisture content on the radon exhalation rate from soil, sand and brick samples that were collected from the North West Frontier Province and Federally Administered Tribal Areas of Pakistan, using CR-39-based radon dosimeters. After processing, samples were prepared by adding 15, 30 and 45% moisture contents (by weight) and were placed in plastic containers. The dosimeters were installed in it at heights of 25 cm above the surface of the samples. These containers were then hermetically sealed and the dosimeters were exposed to radon for 60 to 65 days. After exposure, CR-39 detectors were etched in 25% NaOH at 80 deg.C for 16 h, and track densities were counted. From the measured track densities, exhalation rate was determined using two different approaches. Maximum average radon exhalation rates of 385 ± 86, 393 ± 31 and 362 ± 36 mBq m2 h-1 were observed at 30% moisture content from soil, sand and brick samples, respectively. A slight decrease in exhalation rate was observed in all samples at moisture content of 45%. According to the t-test, change in the exhalation rate as a function of humidity is significant at 95% confidence level. (authors)

  18. Radon exhalation rate from coal ashes and building materials in Italy

    The Italian National Electricity Board, in cooperation with Centro Informazioni Stubi Esperienze (CISE) has a program to assess the hazards connected with using fly ash in civil applications as partial substitutes for cement and other building materials. We investigated the natural radioactivity levels of more than 200 building materials. The survey involved materials available in Italy, categorized by geographical location and type of production. We also examined approximately 100 samples of fly ash from United States and South African coal, obtained from Italian power plants. Exhalation rates from about 40 powdered materials were determined by continuously measuring radon concentration growth in closed containers. Measurements were also performed on whole bricks, slabs, and titles. Details about the high-sensitivity measuring devices are presented. The influence of fly ash on exhalation rates was investigated by accurately measuring radon emanation from slabs with various ash/cement ratios and with slabs of inert materials having various radium concentrations. We will discuss results of forecasting indoor radon concentrations under different ventilation conditions. Two identical test rooms are being built, one with conventional and one with fly-ash building materials, to compare theoretical calculations with experimental data. Specifications for instruments to control and to measure the most important parameters are also discussed

  19. Radon activity and exhalation rates in coal fired thermal power plants

    The combustion of coal in various thermal power plants results in the release of some natural radioactivity to the atmosphere through formation of fly ash and bottom ash or slag. This consequently increases the radioactivity in soil, water and atmosphere around thermal power plants. As the radon in the atmosphere (indoor and outdoor), soil, ground water, oil and gas deposits contributes the largest fraction of the natural radiation dose to populations, enhanced interest exhibited in tracking its concentration is thus fundamental for radiation protection, health and hygiene point of view. In the present study, measurements of radon emanation from coal, fly ash, soil and water samples collected from five thermal power plants of north India have been made using SSNTDs. The average values of radon emanation at equilibrium in the air volume of Cans above different samples varied from 433 ± 28 Bq m-3 to 2086 ± 36 Bq m-3; mass exhalation rates from 13 mBq kg-1 hr-1 to 168 mBq Kg-1hr-1 and surface exhalation rates from 302 mBq m-2hr-1 to 1482 mBq m-2hr-1. The measured average radon concentration in the atmosphere of the thermal power plants have been found to vary from 558 ± 40 Bq m-3 to 682±60 Bq m-3. Based upon these values, the average annual effective doses have also been calculated. (author)

  20. Survey of Gamma Dose and Radon Exhalation Rate from Soil Surface of High Background Natural Radiation Areas in Ramsar, Iran

    Rouhollah Dehghani

    2013-09-01

    Full Text Available Background: Radon is a radioactive gas and the second leading cause of death due to lung cancer after smoking. Ramsar is known for having the highest levels of natural background radiation on earth. Materials and Methods: In this research study, 50 stations of high radioactivity areas of Ramsar were selected in warm season of the year. Then gamma dose and radon exhalation rate were measured.Results: Results showed that gamma dose and radon exhalation rate were in the range of 51-7100 nSv/hr and 9-15370 mBq/m2s, respectively.Conclusion: Compare to the worldwide average 16 mBq/m2s, estimated average annual effective of Radon exhalation rate in the study area is too high.

  1. Prediction of 222 Rn exhalation rates from phosphogypsum based stacks. Part I: parametric mathematical modeling

    Radon-222 is a radionuclide exhaled from phosphogypsum by-produced at phosphate fertilizer industries. Alternative large-scale application of this waste may indicate a material substitute for civil engineering provided that environmental issues concerning its disposal and management are overcome. The first part of this paper outlines a steady-state two-dimensional model for 222Rn transport through porous media, inside which emanation (source term) and decay (sink term) exist. Boussinesq approach is evoked for the laminar buoyancy-driven interstitial air flow, which is also modeled according to Darcy-Brinkman formulation. In order to account for simultaneous effects of entailed physical parameters, governing equations are cast into dimensionless form. Apart from usual controlling parameters like Reynolds, Prandtl, Schmidt, Grashof and Darcy numbers, three unconventional dimensionless groups are put forward. Having in mind 222Rn transport in phosphogypsum-bearing porous media, the physical meaning of those newly introduced parameters and representative values for the involved physical parameters are presented. A limiting diffusion-dominated scenario is addressed, for which an analytical solution is deduced for boundary conditions including an impermeable phosphogypsum stack base and a non-zero fixed concentration activity at the stack top. Accordingly, an expression for the average Sherwood number corresponding to the normalized 222Rn exhalation rate is presented

  2. Environmental impact of radon exhalation rates and radioactivity from various commodities: a review

    Natural radioactivity and its effects on human health is a major environmental concern because of the discovery of widespread occurrence of levels of radon in the ambient air of homes at concentrations that exceed the maximum levels given by the environmental protection agencies. Natural sources of radiation are the concentrations of radionuclides that represent ambient conditions present in the environment which are influenced by human activities. This study presents a review report on natural radioactivity and radon exhalation rate from various commodities such as fly ash of thermal power plants, soil, radiation shielding material etc., from northern and partly eastern part of India which covers Jaduguda uranium mines and others. Most of the building materials of natural origin contain small amounts of Naturally Occurring Radioactive Materials (NORM) and Technologically Enhanced Naturally Occurring Radioactive Materials (TENORM) using fly ash etc. For the natural radioactivity measurement, gamma ray spectrometer was used whereas the radon surface and mass exhalation rates were studied using SSNTDs. The perspective radiation shielding materials using fly ash and other commonly used construction materials have also been investigated for the presence of natural radioactivity. Emphasis was given on the perspective radiation shielding materials using up to 20-25% of fly ash. The radiation attenuation properties were studied for perspective radiation shielding materials using simulation codes and experimental data which shows good agreement between simulation results and experimental values. The radon activity in various samples varies from 20 Bqm-3 to 300 Bqm-3, radon mass and surface exhalation rates were found to vary from 1.05±0.07 to 22±1.2 mBqKg-1h-1 and 9.0±0.30 to 40±1.5 mBqm-2h-1 respectively. Most dominant activity found in the Jaduguda samples, which is due to the presence of uranium in the host rocks and the prevalence of a confined atmosphere within

  3. Measurements of natural radioactivity and radon exhalation rates from different brands of cement used in Pakistan

    The measurement of activity due to the naturally occurring radionuclide has been carried out in different brands of cement available in Pakistan. The gamma spectra of the collected samples were obtained using high-purity germanium detector and analysed for the presence of 232Th, 238U and 40K. The assessment of radiological hazards due to these radionuclides has also been made. The studies concerning the determination of radon-exhalation rates from these samples of cement were also carried out using CR-39 based NRPB radon dosimeters. The range of activity concentrations were found for 226Ra (from 25.10 ± 1.55 to 52.60 ± 3.20 Bq kg-1), 232Th (from 10.30 ± 0.65 to 30.40 ± 1.70 Bq kg-1) and 40K (from 17.25 ± 1.55 to 292.95 ± 23.05 Bq kg-1). The estimated value of radium equivalent concentration was from 11.16 ± 2.60 to 114.98 ± 7.11 Bq kg-1. The calculated absorbed dose rate in air and the annual effective dose were in the range from 18.54 ± 1.17 to 52.90 ± 3.31 nGy h-1 and 0.09 ± 0.01 to 0.26 ± 0.02 mSv, respectively. The external and internal hazard indices were in the range from 0.11 ± 0.01 to 0.31 ± 0.02 and 0.18 ± 0.01 to 0.45 ± 0.03, respectively. The radon exhalation rates from different brands of cement were found in the range from 3.3 ± 0.7 to 8.1 ± 1.7 mBq kg-1 h-1. (authors)

  4. Determination of radon and thoron exhalation rate from the walls surface by CR-39 track detectors

    Solid-state nuclear track detectors are finding expanded uses in various environment research investigations. Inhalation dose due to indoor radon/thoron and their short lived progeny concentrations constitute a major part of the total natural background radiation received by the population. Many measurements of radon concentration in the environment also involve using a dosimeter containing solid state nuclear track detector. The walls of houses included building materials such as granite, bricks, sand, cement etc., contain uranium and thorium in various amounts. Therefore the knowledge of true value exhalation rate of Rn and Tn from building materials represents scientific and practical interest in environmental radiation protection and ecology. In the present work, we have used calibrated plastic cups with two CR-39 detectors. The first detector fixed on bottom of cup in distance of cup height from walls surface and records alpha particles from radon only. The second detector fixed on the top of cup and records alpha particles from thoron and radon. The detected surface of the cup is situated in perpendicular position to surface of the wall. The detectors were exposed for 20-30 days. After exposition, the detectors were chemically etched and analyzed. The exhalation rate per unit area of the concrete, fired and unfired brick walls varied 0.091, 0.078 and 0.1 Bq m-2 h-1 for the radon, 3470, 200 and 5800 Bq m-2 h-1 for the thoron, accordingly. The number and location of radon and thoron alpha tracks were determined using an optical microscope and an image analysis system based on special developed software. The software for track images treatment by application of digital image processing has been developed. All program modules are made in DELPHI execution environment by using Pascal object-oriented language.

  5. Modeling of indoor radon concentration from radon exhalation rates of building materials and validation through measurements

    Building materials are the second major source of indoor radon after soil. The contribution of building materials towards indoor radon depends upon the radium content and exhalation rates and can be used as a primary index for radon levels in the dwellings. The radon flux data from the building materials was used for calculation of the indoor radon concentrations and doses by many researchers using one and two dimensional model suggested by various researchers. In addition to radium content, the radon wall flux from a surface strongly depends upon the radon diffusion length (L) and thickness of the wall (2d). In the present work the indoor radon concentrations from the measured radon exhalation rate of building materials calculated using different models available in literature and validation of models was made through measurement. The variation in the predicted radon flux from different models was compared with d/L value for wall and roofs of different dwellings. The results showed that the radon concentrations predicted by models agree with experimental value. The applicability of different model with d/L ratio was discussed. The work aims to select a more appropriate and general model among available models in literature for the prediction of indoor radon. -- Highlights: • The measurement of indoor radon concentration was carried out by pin hole based dosimeter. • The indoor radon concentration was calculated from different model available in the literature. A comparison of wall flux from two different approaches was carried out for different d/L ratio. • A more appropriate model for prediction of indoor radon concentration was validated

  6. National survey on the natural radioactivity and Rn-222 exhalation rate of building materials in the Netherlands

    de Jong, P.; van Dijk, W.; van der Graaf, E.R.; de Groot, A.V.

    2006-01-01

    The present study reports on results of a nationwide survey on the natural radioactivity concentrations and Rn-222 exhalation rates of the prevailing building materials in the Netherlands. In total 100 samples were taken and analyzed for the activity concentrations of Ra-226, Ra-228, Th-228, and K-4

  7. Radon exhalation rate and natural radionuclide content in building materials of high background areas of Ramsar, Iran

    Radon exhalation rates from building materials used in high background radiation areas (HBRA) of Ramsar were measured using an active radon gas analyzer with an emanation container. Radon exhalation rates from these samples varied from below the lower detection limit up to 384 Bq.m−2 h−1. The 226Ra, 232Th and 40K contents were also measured using a high resolution HPGe gamma- ray spectrometer system. The activity concentration of 226Ra, 232Th and 40K content varied from below the minimum detection limit up to 86,400 Bq kg−1, 187 Bq kg−1 and 1350 Bq kg−1, respectively. The linear correlation coefficient between radon exhalation rate and radium concentration was 0.90. The result of this survey shows that radon exhalation rate and radium content in some local stones used as basements are extremely high and these samples are main sources of indoor radon emanation as well as external gamma radiation from uranium series. -- Highlights: ► In the selection process of local samples, portable scintillometer (NaI) was used. ► The activity concentration of 226Ra varied from below the MDL up to 86400 Bq kg−1. ► The activity concentration of 232Th varied from below the MDL up to 187 Bq kg−1. ► The activity concentration of 40K varied from below the MDL up to 1350 Bq kg−1

  8. Uranium, Radium and Radon Exhalation rate in the soil samples from some areas of Punjab and Haryana states, India

    Uranium, radium concentration and radon exhalation rate have been determined in soil samples from some areas of Punjab and Tusham (Haryana), using the LR-115 plastic track detectors. 'Can Technique' using these detectors, has been used for the estimation of radium concentration and radon exhalation rate and uranium estimation has been carried out in the samples using the fission track technique. Uranium content in these samples has been found to be varying from 1.03 to 9.96 ppm in the Punjab region and varies from 3 to 13.4 ppm for Tusham region. Radium concentration observed for soil samples has been found to be varying from 0.82 to 8.6 Bq Kg-1 for Punjab area and from 2 to 9.31 Bq Kg-1 for Tusham. The Radon exhalation rate in these samples has been found to be varying from 1.2 to 8.83 mBq Kg-1h-1 for Punjab area and from 3.11 to 11.54 mBq Kg-1h-1 for Tusham. A positive correlations with (R2 =0.61) and (R2=0.60) have been found between radon exhalation rate and uranium concentration in the samples from both for the Punjab and Tusham regions respectively. (authors)

  9. Natural 222Rn and 220Rn indicate the impact of the Water–Sediment Regulation Scheme (WSRS) on submarine groundwater discharge in the Yellow River estuary, China

    Highlights: • 220Rn and 222Rn were combined to locate intensive SGD sites. • Influence of WSRS to SGD was found for the first time. • SGD was a dominant nutrient pathway in the Yellow River estuary. - Abstract: Submarine groundwater discharge (SGD) in estuaries brings important influences to coastal ecosystems. In this study, we observed significant SGD in the Yellow River estuary, including a fresh component, during the Water–Sediment Regulation Scheme (WSRS) period. We used the 222Rn and 220Rn isotope pair to locate sites of significant SGD within the study area. Three apparent SGD locations were found during a non-WSRS period, one of which became much more pronounced, according to the remarkably elevated radon levels, during the WSRS. Increased river discharge (from 245 m3 s−1 to 3560 m3 s−1) and the elevated river water level (from 11 m to 13 m) during the WSRS led to a higher hydraulic head, enhancing groundwater discharge in the estuary. Our results suggest that high river discharge (>3000 m3 s−1) might be necessary for elevated fresh submarine groundwater discharging (FSGD). Vertical profiles of salinity, DO and turbidity anomalies along the benthic boundary layer also indicated significant FSGD in the estuary during the WSRS. Nutrient concentrations had positive correlations with 222Rn during a 24-h observation, which indicates that SGD is a dominant nutrient pathway in this area

  10. Radon exhalation in some building construction materials and effect of plastering and paints on the radon exhalation rate using fired bricks

    The technological endeavors of human beings have modified the levels of radiation exposure slightly. The emanation of radon is primarily associated with radium and its ultimate precursor uranium. The radiation dose received by human beings from indoor radon and its progeny is the largest of all doses received either by natural or man-made sources. In order to investigate the effect of paints available in the market on the radon exhalation rate from building materials, several bricks were collected. These bricks were plastered with a mixture of cement and sand. Before measurements bricks were dried for 24 hours. These plastered bricks were then coated with white wash and again dried for 1- 2 hours. After drying the bricks were coated with different brands and colors of paints. Radon exhalation rates measurements were carried out for these painted bricks using 'Sealed can Technique' cylindrical plastic 'Can' of 7.5 cm height and 7.0 cm diameter was sealed to the individual samples by plastic can. In each 'Can' a LR-115 type II plastic detector (2 cm 2cm) was fixed at the top inside of the 'Can', such that the sensitive surface of the detector faces the material and is freely exposed to the emergent radon. Radon decays in the volume of the can record the alpha particles resulting from the 218Po and 214Po deposited on the inner wall of the 'Can'. Radon and its daughters will reach an equilibrium in concentration after one week or more. Hence the equilibrium activity of the emergent radon can be obtained from the geometry of the can and the time of exposure. The results will be discussed. (author)

  11. {sup 220}Rn measurements and implications for earlier surveys of {sup 222}Rn; Meting van {sup 220}Rn en consequenties voor eerdere {sup 222}Rn-surveys. VERA-onderzoek

    Blaauboer, R.O.

    2010-08-15

    The concentration of radioactive radon gas (Rn-222) encountered in newly constructed dwellings was lower than that expected from earlier surveys. An investigation into the response of the radon detectors used in these earlier surveys revealed that these were also sensitive to radioactive thoron (Rn-220), of which more appears to be present than originally assumed. This is the primary outcome of a detailed examination of the detectors that resulted from a national study on radiation exposure in Dutch dwellings constructed between 1994 and 2003. Detectors used in international radon comparison studies have only been set to test for radon, not thoron. Consequently, in practice it is not immediately evident that some detectors actually measure thoron as well, which is also reported as radon. The increasing interest shown by the Netherlands for thoron, provoked by survey results that appear to have been strongly affected by this radioactive isotope of radon, is mirrored by many other countries. The thoron found in dwellings seems to originate from a (frequently used) building material, possibly a finishing material, which has a relatively high thoron exhalation rate. It has more recently been determined that for many years a type of plaster was used in the Netherlands that contained phosphogypsum, a material known for its high radon content. However, it is possible that other materials incorporated into finishing layers also contribute to higher indoor thoron levels. A large portion of the total indoor exposure of occupants to radiation is from inhalation of radioactive decay products of radon and thoron. Radon and thoron are formed in the soil and earth-based building materials by radioactive decay and, because they are gaseous, they are able to diffuse into homes and other buildings. Exposure to ionizing radiation in the home accounts for approximately half of the average annual radiation dose received by a Dutch citizen. [Dutch] Er komt minder radioactief radongas

  12. LR-115 detector response to 222Rn, 220Rn and their progenies, exposed to hemispherical surfaces in free air, and design of a system to calculate their concentrations

    The sensitivities of LR-115 detectors to 222Rn and 220Rn chains in front of hemispherical surfaces of different radii are calculated by the Monte Carlo method. The optimum radii of hemispherical caps are determined, as a result contributions of the different α-emitter nuclei to the track density are differentiated and non-uniform track distribution is avoided. It is demonstrated that if eight detectors are exposed separately in front of the same number of hemispherical surfaces of different radii, the concentrations of each α emitter in airborne and deposited states can be determined. A passive integrating system to calculate the concentrations of radon, thoron and their progenies in free air is given

  13. A technique for discrimination of radon (222Rn) and thoron (220Rn) in soil-gas using solid state nuclear track detectors

    A technique for discrimination of radon (222Rn) and thoron (220Rn) in soil radon emanometry using SSNTDs has been described. It is based on the large ratio of their half lives and consequent difference in their diffusion lengths. It can be computed that a length of about 25 cm of an air column is adequate to eliminate thoron almost completely while radon is not much affected. Theoretical and experimental curves demonstrating the discrimination of radon and thoron using Kodak Pathe LR-115 cellulose nitrate films have been presented. The design of a sonde for the estimation of radon as well as thoron in soil gas for uranium coefficient of radon in air at room temperature has been determined experimentally. (author)

  14. Study of radon exhalation and emanation rates from fly ash samples

    Fly ash, a by-product of burnt coal is technologically important material being used for manufacturing of bricks, sheets, cement, land filling etc. The increased interest in measuring radon exhalation and emanation rates in fly ash samples is due to its health hazards and environmental pollution and the same have been measured to assess the radiological impact of radon emanated from fly ash disposal sites. Samples of fly ash from different thermal power stations in northern India and National Council for Cement and Building Materials (NCB) were collected and analysed for the measurements. For the measurement, alpha sensitive LR-115 type II plastic track detectors were used. Gamma spectrometry and can technique was used for the measurements. The experimental data show that fly ash samples emanate radon in significant amount and this consequently, may result in increased radon levels in dwellings built by using fly ash bricks and excessive radiation exposure to workers residing in the surroundings of fly ash dumping sites. (author)

  15. Assessment of radon-222 concentrations and exhalation rates of rocks and building materials

    One hundred samples were collected from two regions (Bir El-Sid and Wady El-Gemal ) in the Nile Valley. It contain various types of igneous and metamorphic rock samples (acidic dykes, intermediate dykes, basic dykes, serpentinite, metagabbro, menalge). Another set of samples were collected from different regions of Germany. Samples were analyzed and the concentrations in Bq/kg dry weight of radium were determined by gamma-ray spectrometry using hyper-pure germanium (HPGe) detector. A direct method is used to measure 222Rn emanated from the samples, which was analyzed in laboratory using the portable radon monitor Prassi. 222Rn activity concentrations (Bq/m3) were in the range from 36.1± 2 to 96.4 ± 6, 17.8 ± 3 to 73.6 ± 4 and 18.0 ± 2 to 188.1 ± 15 Bq/m3 for samples collected from Bir Elsid, Wadi El-Gemal and samples from Germany respectively. The corresponding values of exhalation rates were from 0.0012 to 0.004, 0.005 to 0.015 and 0.007 to 0.0069 Bq/gs for these areas respectively. (author)

  16. Study of environmental radio activity and radon exhalation rate in some plant samples from some area of Pakur, Jharkhand

    Uranium is a radiotoxic element found in trace quantity in almost all natural occurring materials like soil, rock and sand etc. Radon an inert radioactive gas whose predecessor is Uranium is emitted from soil beneath the house and from building materials. In the present studies, the environmental radioactivity of some plants leaf were measured by using plastic track detectors LR-115, type II, manufactured by Kodak. Track densities measured in terms of track cm-2 day-1, shows a variation from 10.6 track cm-2 day-1 to 42.8 track cm-2 day-1. The technique has been used to determine the Radon exhalation rate of the plants leaf samples collected from the same area. The Radon exhalation rate varies from 0.194 m Bq-1h-1 to 0.435 m Bq-1 h-1. (author)

  17. Study of natural radioactivity and 222Rn exhalation rate in soil samples for the assessment of average effective dose

    The activity concentration of natural radionuclides and 222Rn (Radon) exhalation rate in soil samples were determined using NaI Scintillation detector and Scintillation Radon Monitor. Soil samples were collected from different geological formations of the same area. The average value of 226Ra (Radium) equivalent activity in soil samples of the studied area was 124.9 Bq kg-1. 226Ra equivalent activities was calculated for the analyzed samples to assess the radiation hazards arising due to the use of these soil samples in the construction of dwellings. The 222Rn exhalation rate in the studied area was varied from 6.9 ± 0.2 mBq Kg-1 h-1 to 33.2 ± 2 mBq Kg-1. A positive correlation was obtained between the Ra (Radium) and 222Rn exhalation rate. The overall average annual effective dose in the studied is lower than the world recommended value of 1.0 mSva-1. (author)

  18. An Overview on Studying 222Rn Exhalation Rates using Passive Technique Solid-State Nuclear Track Detectors

    Mohamed Abd-Elzaher

    2012-01-01

    Full Text Available Problem statement: Uranium is a radiotoxic element found in trace quantities in alomost all natural accurring materials like soil, rock. Radon an inert radioactive gas whose predecessor in uranium, is emitted from soil beneath the house and from building materials. Accurate knowledge of exhalation rate plays an important role in characterization of the radon source strength in some building materials and soil. It is a useful quantity to compare the relative importance of different sample of building materials and soil. Approach: This study provides an overview of measurements of radon exhalation rates for selected samples in Egypt were carried out using passive measuring techniques were measured by Can Technique using LR-115 type II plastic track detectors. Results: The radon concentration varies from 2.44-29 k Bq m-3 and the corresponding values of surface exhalation rates from 4.16-26.24 Bq m-2. h the radium content 226Ra results in all samples under test in increasing order of magnitude. From the results it can be noticed that The lowest value of 226Ra is 7 Bq kg-1 in Sand sample, while the highest value is 85 Bq kg-1 Ordinary Cement. Conclusion: All the values of radium content in all samples under test were found to be quite lower than the permissible value of 370 Bq kg-1 recommended by Organization for Economic Cooperation and Development."

  19. Radon exhalation rate from and natural radioactivity in building materials from HLNRAs of Ramsar, lran

    Some areas of Ramsar, a city in northern Iran, have among the highest known background radiation levels in the world. Indoor radon has been recognized as one of the health hazards for people who living in this area. The high background radiation in the 'hot' areas of Ramsar is primarily due to the presence of very high amounts of 226Ra and its decay products, which were brought to the earth's surface by hot springs. Area resident have also used the residue of the hot springs as building materials for construction of houses, which are considered as one of the major sources of this gas in indoor environment in these areas. These building materials have been studied for exhalation rate of radon. The radionuclide content of the building materials were determined. A total of 35 samples were analyzed for 226Ra, 232Th and 40K using a low background High Purity Germanium detector (HPGe). The detector was surrounded by a massive lead shield (10 cm) and coupled to a MCA-Series 100. The system was calibrated with respect to energy and efficiency using reference materials (RGU-1), (RGTh-1) and (RGK-1) that were prepared by International Atomic Energy Agency. The mean activity concentrations of radionuclides in most of them are not very high, and these values are near the normal radiation background. The highest values for the activity concentration of different radionuclides and the exposure rate due to natural radionuclides in this study were observed for the building materials that have made from travertine deposits

  20. Study of radon exhalation rate from different types of surfaces of building and activity of 226Ra in building materials

    Radon exhalation rate from different surfaces of ground floor vary from 0.95 -3.2 mBq.m-2.s-1. The average value in the first floor surface is 1.2 mBq.m-2.s-1 and exhalation from walls vary from 0.752 - 3.85 mBq.m-2s-1 and with a bare surface it is 5.49 mBq.m-2.s-1. The activity of 226Ra in building materials is estimated by using emanometer. The activity of 226Ra is low in sand (4.01 Bq.kg-1) and is high for granite (55 Bq.kg-1), and almost same in concrete and brick. The activity of 226 Ra in building materials is low compared to the global average. (author)

  1. Study of radon exhalation rate from different types of building construction materials using SSNTDds and estimation of lung cancer risk

    Uranium is a radiotoxic element found in trace quantities in almost all naturally occurring materials like soil, rock and sand etc. Building materials are derived from these materials. Radon, an inert radioactive gas whose predecessor is uranium is emitted from soil beneath the house and from building materials. Building materials are the main source of radon inside the dwellings. Because of low level of radon emanation from these materials, long term measurements are needed. Can technique using LR-115 type II solid state nuclear track detector has been employed for the measurement of radon activity and radon exhalation rate from a number of building materials commonly used for construction in Kerala. Radon activity is found to vary from 75.0 to 2212.7 Bqm-3 with an average value of 477.7 Bqm-3, radon exhalation rate from 44.0 to 1337.7 mBqm-2h-1 with an average value of 286.3 mBqm-2h-1 and effective dose equivalent from 5.2 to 157.7 μSv y-1 with an average value 33.7 μSv y-1 for different building construction materials. Radon emanation from granite is found to be maximum while cement brick (hollow) and Kadappa stone give minimum radon emanation. In the case of plastered bricks covered with sealants, radon exhalation is found to increase slightly with acrylic exterior and acrylic emulsion while it decreases with others. (author)

  2. FeNO measured at fixed exhalation flow rate during controlled tidal breathing in children from the age of 2 yr

    Buchvald, F; Bisgaard, H

    2001-01-01

    We have outlined a new method to measure exhaled nitric oxide on-line at fixed flow rate during controlled tidal breathing (FeNO [controlled]) in young children aged 2 yr and older. FeNO(controlled) measures NO on-line during operator-controlled tidal breathing. The operator targets the exhaled...... flow of the child within preset limits of 0.4-0.6 L/s by continuously adjusting an expiratory resistance. FeNO(controlled) is estimated during end exhalation. We have validated this method against the reference method of the single breath on-line (SBOL) maneuvre (FeNO[SBOL]) and compared...

  3. Determining the radon exhalation rate from a gold mine tailings dump by measuring the gamma radiation

    The mining activities taking place in Gauteng province, South Africa have caused millions of tons of rocks to be taken from underground to be milled and processed to extract gold. The uranium bearing tailings are placed in an estimated 250 dumps covering a total area of about 7000 ha. These tailings dumps contain considerable amounts of radium and have therefore been identified as large sources of radon. The size of these dumps make traditional radon exhalation measurements time consuming and it is difficult to get representative measurements for the whole dump. In this work radon exhalation measurements from the non-operational Kloof mine dump have been performed by measuring the gamma radiation from the dump fairly accurately over an area of more than 1 km2. Radon exhalation from the mine dump have been inferred from this by laboratory-based and in-situ gamma measurements. Thirty four soil samples were collected at depths of 30 cm and 50 cm. The weighted average activity concentrations in the soil samples were 308 ± 7 Bq kg−1, 255 ± 5 Bq kg−1 and 18 ± 1 Bq kg−1 for 238U, 40K and 232Th, respectively. The MEDUSA (Multi-Element Detector for Underwater Sediment Activity) γ-ray detection system was used for field measurements. The radium concentrations were then used with soil parameters to obtain the radon flux using different approaches such as the IAEA (International Atomic Energy Agency) formula. Another technique the MEDUSA Laboratory Technique (MELT) was developed to map radon exhalation based on (1) recognising that radon exhalation does not affect 40K and 232Th activity concentrations and (2) that the ratio of the activity concentration of the field (MEDUSA) to the laboratory (HPGe) for 238U and 40K or 238U and 232Th will give a measure of the radon exhalation at a particular location in the dump. The average, normalised radon flux was found to be 0.12 ± 0.02 Bq m−2 s−1 for the mine dump. - Highlights: • Obtain radon flux from a large area

  4. Estimation of radon exhalation rate, natural radioactivity and radiation doses in fly ash samples from NTPC Dadri, (UP) India

    Fly ash produced by coal-burning in thermal power station has become a subject of world wide interest in recent years, because of its diverse uses in building materials such as bricks, sheets, cement and land filling etc. The knowledge of radio nuclides in fly ash plays an important role in health physics. Natural radioactivity and radon exhalation rate in fly ash samples collected from NTPC (National Thermal Power Corporation) Dadri, (UP.) India, have been studied. A high resolution gamma ray spectroscopic system has been used for the measurement of natural radioactivity. The activity concentration of natural radionuclides radium (226Ra), thorium (232Th) and potassium (40K) were measured and radiological parameters were calculated. Radium concentration was found to vary from (81.01 ± 3.25) to (177.33 ±10.00) Bq kg-1. Activity concentration of thorium was found to vary from (111.57 ± 3.21) to (178.50 ± 3.96) Bq kg-1. Potassium activity was not significant in some samples, whereas, some other samples have shown potassium activity vary from (365.98 ± 4.85) to (495.95 ± 6.23) Bq kg-1. Radon exhalation rates in these samples were also calculated by 'Sealed Can technique' using LR-115 type II detectors and found to vary from (80 ± 9) to (243 ± 16) mBqm-2h-1 with an average value (155 ± 13) mBqm-2h-1. This study also presents the results of estimation of effective dose equivalent from exhalation rate, radium equivalent, absorbed gamma dose rates, external annual effective dose rate and values of external hazard index for the fly ash samples. (author)

  5. Natural radioactivity, radon exhalation rates and indoor radon concentration of some granite samples used as construction material in Turkey

    It is very important to determine the levels of the natural radioactivity in construction materials and radon exhalation rate from these materials for assessing potential exposure risks for the residents. The present study deals with 22 different granite samples employed as decoration stones in constructions in Turkey. The natural radioactivity in granite samples was measured by gamma ray spectrometry with an HPGe detector. The activity concentrations of 226Ra, 232Th and 40K were found to be in the range of 10-187, 16-354 and 104-1630 Bq kg-1, respectively. The radon surface exhalation rate and the radon mass exhalation rate estimated from the measured values of 226Ra content and material properties varied from 1.3 to 24.8 Bq m-2 h-1 with a mean of 10.5±1.5 Bq m-2 h-1 and 0.03-0.64 Bq kg-1 h-1 with a mean of 0.27±0.04 Bq kg-1 h-1, respectively. Radon concentrations in the room caused from granite samples estimated using a mass balance equation varied from 23 to 461 Bq m-3 with a mean of 196±27 Bq m-3. Also the gamma index (Iγ), external indoor annual effective dose (Eγ) and annual effective dose due to the indoor radon exposure (ERn) were estimated as the average value of 1.1±0.1, 0.16±0.02 mSv and 5.0±0.7 mSv, respectively, for the granite samples. (authors)

  6. Study on radon exhalation rate from Indian granite samples using nuclear track detector based passive method as well as dynamic method

    Building materials being important source of indoor radon concentrations, radon exhalation rate from building material samples had gained wide attention over decades. Among them some granite varieties were reported to show high radon exhalation rate. Eight different varieties of Indian granite samples were analyzed for radon surface exhalation rate using active as well as passive methods. Sealed-can technique with LR115 nuclear track detector was used in the passive method and Scintillation based SRM online radon monitor was used in the active dynamic method. The radon exhalation rate from the tiles measured using SSNTD based passive method ranged from 0.016 ± 0.003 Bq m-2h-1 to 3.5 ± 0.5 Bqm-2h-1 with an average value of 0.899 Bq m-2h-1, whereas deviations were observed in the case of dynamic method results. The details of the study are reported. A comparative analysis on passive and dynamic method of exhalation rate measurement also has been carried out looking into thoron interference and radon leakage issues from closed chambers (author)

  7. Field GE gamma spectrometry for on site measurements of some parameters characterizing radon-222 exhalation rates from soils and covers

    We describe a new method based on differential gamma spectrometry for on site determination of some of the parameters which are relevant for the production of radon 222 in soil gas and its transfer from soil to indoor and outdoor atmospheres. This method is investigated in the context of a 3-year Slovenian-French cooperation programme, the PROTEUS project. We are currently using a germanium detector of 100 cm3. The height of the 20 deg. C collimated detector above the soil surface is from 1.5 to 3 m when using a tripod. This arrangement provides results which are representative of soil areas ranging from 1 to 4 square metres. Routine measurements would require larger detector volumes. The main objective is to provide technology and methodology for an efficient mapping of zones with potential for being the source of a high level of indoor radon, eliminating the need for soil sampling followed by laboratory analysis. The feasibility of an airborne mapping laboratory flying at low altitude will be investigated. Another objective is the rapid measurement of radon profiles across covers used to reduce exhalation rates from the surface of a pile of tailings, with characterisation of the influence of humidity content of the top layer. Airborne survey would allow for measuring exhalations from surfaces of slurries not otherwise accessible. (author)

  8. Prediction of 222 Rn exhalation rates from phosphogypsum based stacks. Part II: preliminary numerical results

    The first part of this paper proposes a steady-state 2-D model for 222 Rn transport in phosphogypsum stacks. In this second part, the dimensionless model equations are solved numerically with the help of an existing finite-volume simulator that has been successfully used to solve heat and mass transfer problems in porous media. As a test case, a rectangular shaped stack is considered in order to verify the ability of the proposed parametric approach to account for concurrent effects on the 222 Rn exhalation into the local atmosphere. Air flow is supposed to be strictly buoyancy driven and the ground is assumed to be impermeable to 222 Rn and at a higher temperature under the stack base. Dimensionless controlling parameters are set to representative values and results are presented for Grashof number in the range 106 ≤Gr≤ 108, corresponding to very small to small temperature differences between incoming air and ground underneath the stack base. For the particular set of parameters and inasmuch as Gr increases, streamlines presented basically the same pattern while internal isotherms and iso concentration lines remained almost unchanged. Total average Sherwood number proved to be rather insensitive to Gr while total average Nusselt increased slightly with Gr. (author)

  9. Exposure to exhaled air from a sick occupant in a two-bed hospital room with mixing ventilation: effect of distance from sick occupant and air change rate

    Bolashikov, Zhecho Dimitrov; Melikov, Arsen Krikor; Georgiev, Emanuil

    2011-01-01

    Full-scale measurements were performed in a climate chamber set as a two-bed hospital room, ventilated at 3, 6 and 12 h-1. Air temperature was kept constant at 22 °C. Two breathing thermal manikins were used: a sick patient lying on one side in one bed and a doctor. A thermal dummy mimicked...... an exposed patient lying in the second bed. The doctor stood 0.55 m or 1.1 m facing the sick patient. The breathing mode of the “sick patient” was: exhalation mouth/inhalation nose. Tracer gas (R-134a) was mixed with the exhaled air. Important finding of this study is that airflow distribution...... and interaction in rooms, distance between the source and recipient, etc. may play more important role for the exposure to the air exhaled by the sick patient than the ventilation rate. Increase in ventilation may affect adversely the exposure to exhaled air and thus enhance the risk from airborne cross infection....

  10. 222Rn and 220Rn concentrations measured in various natural honey samples by using nuclear track detectors and resulting radiation doses to the members of the rural populations in Morocco

    Radon (222Rn) and thoron (220Rn) concentrations were measured in sixteen natural honey material samples collected from different regions in Morocco by using CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs). The concentrations of these radionuclides were also measured in nectar solutions corresponding to the studied honey samples. The measured concentrations of 222Rn and 220Rn in honey samples ranged from (2.3 ± 0.2) to (8.1 ± 0.6) Bq.l-1 and (1.8 ± 0.1) to (3.9 ± 0.3) Bq.l-1, respectively. Committed equivalent doses due to annual intakes of 222Rn were evaluated in the human gastrointestinal tract compartments of adult members of the Moroccan populations from the ingestion of studied honey samples. The influence of the target tissue mass and activities due to 222Rn on the annual committed equivalent doses in the compartments of the human gastrointestinal tract was investigated. (authors)

  11. Extensive radioactive characterization of a phosphogypsum stack in SW Spain: {sup 226}Ra, {sup 238}U, {sup 210}Po concentrations and {sup 222}Rn exhalation rate

    Abril, Jose-Maria, E-mail: jmabril@us.es [Dpto. Fisica Aplicada I, Universidad de Sevilla, EUITA, Ctra Utrera Km 1, 41013 Seville (Spain); Garcia-Tenorio, Rafael, E-mail: gtenorio@us.es [Dpto. Fisica Aplicada II, Universidad de Sevilla, ETSA, Avda. Reina Mercedes s/n, 41012 Seville (Spain); Manjon, Guillermo, E-mail: manjon@us.es [Dpto. Fisica Aplicada II, Universidad de Sevilla, ETSA, Avda. Reina Mercedes s/n, 41012 Seville (Spain)

    2009-05-30

    Phosphogypsum (PG) is a by-product of the phosphate fertilizer industries that contains relatively high concentrations of uranium series radionuclides. The US-EPA regulates the agriculture use of PG, attending to its {sup 226}Ra content and to the {sup 222}Rn exhalation rate from inactive stacks. Measurements of {sup 222}Rn exhalation rates in PG stacks typically show a large and still poorly understood spatial and temporal variability, and the published data are scarce. This work studies an inactive PG stack in SW Spain of about 0.5 km{sup 2} from where PG can be extracted for agriculture uses, and an agriculture soil 75 km apart, being representative of the farms to be amended with PG. Activity concentrations of {sup 226}Ra, {sup 238}U and {sup 210}Po have been measured in 30 PG samples (0-90 cm horizon) allowing for the construction of maps with spatial distributions in the PG stack and for the characterization of the associated PG inputs to agriculture soils. Averaged {sup 226}Ra concentrations for the stack were 730 {+-} 60 Bq kg{sup -1} (d.w.), over the US-EPA limit of 370 Bq kg{sup -1}. {sup 222}Rn exhalation rate has been measured by the charcoal canister method in 49 sampling points with 3 canisters per sampling point. Values in PG stack were under the US-EPA limit of 2600 Bq m{sup -2} h{sup -1}, but they were one order of magnitude higher than those found in the agriculture soil. Variability in radon emissions has been studied at different spatial scales. Radon exhalation rates were correlated with {sup 226}Ra concentrations and daily potential evapotranspiration (ETo). They increased with ETo in agriculture soils, but showed an opposite behaviour in the PG stack.

  12. Exposure to Exhaled Air from a Sick Occupant in a Two-Bed Hospital Room with Mixing Ventilation: Effect of Posture of Doctor and Air Change Rate

    Bolashikov, Zhecho Dimitrov; Melikov, Arsen Krikor; Barova, Mariya

    2013-01-01

    Full-scale measurements were performed in a climate chamber set as a two-bed hospital room, ventilated at 3, 6 and 12 ACH with overhead mixing ventilation. Air temperature was kept constant at 22 °C. Two breathing thermal manikins were used to mimic a sick patient lying on one side in one...... the ventilation rate itself. Furthermore, increase in ventilation may affect adversely the exposure to exhaled air and thus enhance the risk from airborne cross infection....

  13. The exhalant jet of mussels Mytilus edulis

    Riisgard, Hans Ulrik; Jørgensen, Bo Hoffmann; Lundgreen, Kim;

    2011-01-01

    The exhalant jet flow of mussels in conjunction with currents and/or other mussels may strongly influence the mussels' grazing impact. Literature values of mussel exhalant jet velocity vary considerably and the detailed fluid mechanics of the near-mussel flow generated by the exhalant jet has...... shell lengths. Here, we present results of a detailed study of fully open mussels Mytilus edulis in terms of filtration rate, exhalant siphon aperture area, jet velocity, gill area and body dry weight, all as a function of shell length (mean +/- SD) over the range 16.0 +/- 0.4 to 82.6 +/- 2.9 mm......, with the corresponding scaling laws also presented. The exhalant jet velocity was determined by 3 methods: (1) measured clearance rate divided by exhalant aperture area, (2) manual particle tracking velocimetry (PTV) using video-microscope recordings, and (3) particle image velocimetry (PIV). The latter provides...

  14. Study of radon exhalation rates using solid state nuclear track detectors in stone mining area of Aravali range in Pali region, district Faridabad

    It is well established that indoor radon-thoron and daughters are the largest contributor to total radiation dose received by populations. They account for more than 50% of the total dose and the radiation exposure beyond permissible levels can lead to deleterious effects on health. This fact necessitates extensive studies of natural radioactivity levels in the stone mining area of Aravali range in Faridabad. The stone mining area of Aravali Range in Pali, District Faridabad bears significant geological features. Radon exhalation from ground plays an important role in enhanced indoor radon levels and can pose grave health hazards to the workers and the residents. Exhalation rates (mass and surface) from stone samples of the area have been studied using LR-115, Type II nuclear track detectors. The mass and surface exhalation rates from crushed stone samples, also called stone dust varied in the range 3.41-9.11 mBq kg-1 h-1 and 75.9-202.7 mBq m-2 h-1, respectively. The study has revealed substantial presence of radionuclides in the samples collected from the mining area. (author)

  15. Radium activity and radon exhalation rates from phosphate ores using CR-39 on-line with an electronic radon gas analyzer 'Alpha GUARD'

    Saad, A.F. [Physics Department, Faculty of Science, Zagazig University, Zagazig (Egypt)], E-mail: abdallahsaad@hotmail.com

    2008-08-15

    Nuclear track detectors (NTDs) have seen a major expansion in application to general physical and geological problems reflecting its advances in understanding the exhalation dependence of radon as well as radon and radium concentration distributions in the earth's crust. However, considerable uncertainties still persist, in particular, concerning the detection efficiency of track detectors which are not calibrated precisely to a standard method or an active detector of a unique efficiency. In this investigation, CR-39 NTDs and an electronic radon gas analyzer 'Alpha GUARD' were used for the measurement of radon exhalation rate and radium concentration in phosphate samples collected from two different mines of El-Sobaeya and El-Suez, Egypt. The phosphate sample was loaded into an emanation container (Genitron Instruments GmbH) equipped with a PC-based radon gas analyzer. The CR-39 track detectors were mounted inside a diffusion cup used simultaneously with the Alpha GUARD radon gas analyzer. Radium activity in phosphate samples was found to vary from 1.8 to 361.3kBqkg{sup -1}. The radon exhalation rates in these samples were found to vary from 0.020 (0.003) to 4.125Bqm{sup -2}h{sup -1}(0.658Bqkg{sup -1}h{sup -1})

  16. Study on radon exhalation rate in sedimentary and igneous rocks used as building materials in Tiruchirappalli district, Tamil Nadu, India

    Tiruchirappalli district is naturally endowed with rich building material resources which are also used in neighboring districts. Hence, measurement of radon level in these building materials is important to assess its impact on human health. The present study was undertaken to measure the activity concentration of radon in 8 sedimentary rock (stone rock) quarries and 6 igneous rocks (granite) quarries. Sealed Can Technique using Solid State Nuclear Track Detector was employed for the measurement of radon emanation. The activity concentration of radon in sedimentary rocks ranged from 18.8 ± 0.3 Bqm-3 to 56.0± 4.8 Bqm-3 with the mean concentration of 29.47 ± 12.6 Bqm-3. However, radon concentrations in igneous rocks are distinctly higher and ranged from 47.8 ± 4.0 Bqm-3 to 570.0 ± 95.0 Bqm-3 with the mean value of 273.5 ± 167.7 Bqm-3. The mean radium concentration (CRa) was recorded in both sedimentary (2.13 ± 0.94 Bqkg-1) and igneous rocks (20.4 ± 12.59 Bqkg-1) were well within the limit prescribed for dwellings (370 Bq kg-1). The mass and surface exhalation rates were also calculated in all the rock samples. The study concludes that the sedimentary rocks and the igneous rocks analyzed were radiologically safe when used as building materials expect the granite rock from Narthamalai (S13) which registers a higher mean radon activity of 570.0 ± 95.0 Bq m-3. (author)

  17. Health assessment of natural radioactivity and radon exhalation rate in granites used as building materials in Lebanon

    Measurements of specific activities (Bq kg-1) of gamma-emissions from radioactive nuclides, 238U, 226Ra, 214Bi, 232Th, 212Pb and 40K, contained in 28 granite types, used as building materials in indoors in Lebanon, were performed on the powdered granites. The concentration of the nuclides, 226Ra, 232Th and 40K, in the granites varied from below detection level (BDL) to 494 Bq kg-1, BDL to 157.2 Bq kg-1 and BDL to 1776 Bq kg-1, respectively. 226Ra concentration equivalents, CRaeq, were obtained and ranged between 37 and 591 Bq kg-1, with certain values above the allowed limit of 370 Bq kg-1. Calculated annual gamma-absorbed dose in air, DaR, varied from 17.7 to 274.5 (nGy h-1). Annual effective dose, E (mSv y-1), of gamma radiations related to the studied granites and absorbed by the inhabitants was evaluated. E (mSv y-1) ranged from 0.09 to 1.35 mSv y-1. Some granite types produced E above the allowed limit of 1 mSv y-1 set by ICRP. Values of 222Rn mass exhalation rate, EM (mBq kg-1h-1), in granite powder were obtained using the CR-39 detector technique. Diffusion factors, f, in 23 granite types were calculated with f ranging between (0.1±0.02)x10-2 and (6.6±1.01)x10-2. (authors)

  18. LR-115 detector response to {sup 222}Rn, {sup 220}Rn and their progenies, exposed to hemispherical surfaces in free air, and design of a system to calculate their concentrations

    Palacios, D. [Universidad Simon Bolivar, P.O. 89000, Caracas (Venezuela)], E-mail: palacios@usb.ve; Palacios, F. [Universidad de Oriente, Santiago de Cuba (Cuba); Sajo-Bohus, L.; Barros, H.; Greaves, E.D. [Universidad Simon Bolivar, P.O. 89000, Caracas (Venezuela)

    2008-08-15

    The sensitivities of LR-115 detectors to {sup 222}Rn and {sup 220}Rn chains in front of hemispherical surfaces of different radii are calculated by the Monte Carlo method. The optimum radii of hemispherical caps are determined, as a result contributions of the different {alpha}-emitter nuclei to the track density are differentiated and non-uniform track distribution is avoided. It is demonstrated that if eight detectors are exposed separately in front of the same number of hemispherical surfaces of different radii, the concentrations of each {alpha} emitter in airborne and deposited states can be determined. A passive integrating system to calculate the concentrations of radon, thoron and their progenies in free air is given.

  19. Radon exhalation rates corrected for leakage and back diffusion – Evaluation of radon chambers and radon sources with application to ceramic tile

    M. Abo-Elmagd

    2014-10-01

    Full Text Available The natural radon decay, leakage and back diffusion are the main removal processes of radon from its container. Ignoring these processes leads to underestimate the measured value of radon related parameters like exhalation rate and radium content. This work is aimed to evaluate two different radon chambers through determining their leakage rate λv and evaluation of radon source by determine its back diffusion rate λb inside the evaluated radon chambers as well as a small sealed cup. Two different methods are adapted for measuring both the leakage rate and the back diffusion rate. The leakage rate can be determined from the initial slope of the radon decay curve or from the exponential fitting of the whole decay curve. This can be achieved if a continuous monitoring of radon concentration inside the chamber is available. Also, the back diffusion rate is measured by sealing the radon source in the chamber and used the initial slope of the buildup curve to determine λb and therefore the exhalation rate of the source. This method was compared with simple equation for λb based on the ratio of the source to the chamber volume. The obtained results are applied to ceramic tile as an important radon source in homes. The measurement is targeted the ceramic glaze before and after firing as well as the obtained tile after adhere the glaze on the tile main body. Also, six different tile brands from Egyptian market are subjected to the study for comparison.

  20. Estimation of soil exhalation rate and indoor radon concentration in air using RAD7 for health risk assessment in Hisar district, Haryana

    For the health risk assessment of the residents because of the exposure to indoor radon concentration in the dwellings an active technique using RAD7 (an electronic radon detector) has been employed in the 50 dwellings in the studied area of Hisar district of Haryana, India. Also the average annual effective dose due to radon gas has been calculated. The estimation of radon gas exhalation rates in the 50 soil samples collected from the studied area has also been carried out by sealed Can Technique using LR-115 solid state nuclear track detectors (SSNTDs). The measured surface exhalation rates in the soil samples vary from 189.74 to 285.99 mBq m-2h-1 and mass exhalation rates vary from 8.61 to 11.16 mBq kg-1h-1. The measured indoor radon values in the study area varies from 51.09 to 324.23 Bq m-3 with an average value of 191.80 Bq m-3 which is well within the recommended action level 200-300 Bq m-3 (ICRP, 2009) in about 80% of the samples and is slightly above 300 Bq m-3 in only about 20% of the samples. The indoor radon values obtained in the present investigation are more than the world average of 40 Bq m-3 The annual average dose received by the residents of the study area varies from 1.29 mSv to 8.17 mSv with an average value of 4.83 mSv which was calculated using parameters introduced in report by UNSCEAR (2000) and these values are within the recommended safe limit of 3 mSv to 10 mSv. These values suggest that there is no significance threat to the human beings due to the presence of natural radon in the dwellings. (author)

  1. A preliminary Investigation of 222Rn and 220Rn levels in non-uranium mines in China%我国非铀矿山222Rn和220Rn水平初步调查研究

    尚兵; 崔宏星; 武云云; 张庆召; 苏旭

    2008-01-01

    Objective To measure levels of 222Rn and 220Rn in typical non-uranium mines, China, and to estimate dose from the occupational radon exposure in the miners. Methods Using typical sampling scheme,44 mines were selectcd in 12 provinces, which can be classified into 4 categories and 17 types of mines. The radon-thoron discriminative detectors were used to measure 222Rn and 220Rn concentrations in mines. Result The concentration of 222Rn or 220Rn was log-normally distributed. The arithmetic mean (AM) concentration and geometric mean (GM) concentration of 222Rn and 220Rn in 25 metal mines (n=147) were estimated to be (1211±2359) Bq/m3(AM) and (311±5.5) Bq/m3(GM), and (269±700) Bq/m3(AM) and (71±4.4)Bq/m3(GM), respectively. The mean concentrations of 222Rn and 220Rn in 18 non-metal mines (n=118) were (98±207) Bq/m3(AM) and(55±2.5) Bq/m3(GM), and (60±76) Bq/m3(AM) and (38±2.4)Bq/m3(GM),respectively. In total, we measured 222 Rn concentration in 44 underground mines, 6 of them, accounted for 15%, with the mean radon concentration exceeding 1000 Bqm-3 (limit of workplace in China). Approximately 7% of radon concentration in mines measured were higher than 3700 Bq/m3(current limit in uranium mine in China), some points even exceeded 10 000 Bq/m3. Based on this typical measurements, the equilibrium factor for 222Rn was estimated to be 0.33±0.15 in underground mines and 0.47±0.18 in nearby houses. Equilibrium factor for 222Rn ranged from 0.001 to 0.032. Using the data obtained in this typical survey, the average annual effective dose of underground miners exposed to radon and thoron was estimated to be 8.15 mSv/a. Conclusions High levels of 222Rn exists in metal mines, such as copper, tin, lead and zinc, gold, and aluminum mines among others. More study and administrative measures are needed to address the radiation protection of workers occupationally exposed to high radon in mines.%目的 测量非铀矿山222Rn、220Rn水平,了解我国矿山氡超标比

  2. Estimation of dose contribution from 226Ra, 232Th and 40K radon exhalation rates in soil samples from Shivalik foot hills in India.

    Chauhan, R P; Chauhan, Pooja; Pundir, Anil; Kamboj, Sunil; Bansal, Vakul; Saini, R S

    2014-01-01

    The concentration of radium, thorium and potassium and radon exhalation rates in soil samples collected from Shivalik foot hills in the states of Haryana and Himachal Pradesh (India) were experimentally measured. A high-resolution gamma-ray spectroscopic system was used for the measurement of natural radioactivity ((226)Ra, (232)Th and (40)K) at Inter-University Accelerator Center, New Delhi, using a coaxial n-type high-purity germanium detector (EG&G, ORTEC, Oak Ridge, USA). The mass exhalation rates (EM) of radon in soil samples from the study area measured by 'sealed canister technique' using LR-115 type II track detectors varied from 50±1 to 143±6 mBqkg(-1) h(-1). The activity concentrations of (226)Ra, (232)Th and (40)K in various soil samples of the study area varied from 31±1.3 to 63±4.6, 53±1.8 to 78±2.6 and 472±4.8 to 630±7.0 Bq kg(-1) respectively. The results indicated some higher levels of radioactivity in Lal Dhang peak area of the hills compared with other locations under study. PMID:23893776

  3. Attempts on determination of radon exhalation rate from a waste-dump of Bogdanka coal mine with use of the Picorad detectors

    The Bogdanka coal mine is located in the Pojezierze Leczynsko-Wlodawskie district in the vicinity of the Poleski National Park. From the beginning of mining activity, i.e. for the last 20 years, waste rock has been deposited close by. It consists mainly of clumps (about 88%) of a few centimeters grain-size, while sandstones, siderite and mudstones form the rest. A storage yard, filled to about 30%, covers an area of 83 ha and is partly cultivated. It is well known that deposited waste rocks of coal mines may be a source of radon. The emission rate of this element from a spoil dump depends on many factors, so direct measurements of the exhalation rate are the most reliable. Passive detectors containing activated carbon (Picorad, Niton-Canberra-Packard), designed for the detection of stable concentrations of indoor radon were used. An application of these detectors in open areas may produce errors associated with the higher humidity and variable concentrations of exhaled radon. The radioactivity of radon and its daughters was determined using a liquid scintillation spectrometer (Quantulus, Wallac-Perkin-Elmer). Measurements were made at several points on the spoil dump, including where waste was most recently deposited and cultivated sites. A calibration of the detectors with various radon concentrations and humidity levels was performed in a radon chamber at the Central Mining Institute. (author)

  4. The influence of the nature of soil and plant and pollution on the 238U, 232Th, 222Rn and 220Rn concentrations in various natural honey samples using nuclear track detectors: Impact on the adult consumers

    M A Misdaq; A Mortassim

    2009-11-01

    238U and 232Th concentrations as well as 222Rn and 220Rn -activities per unit volume were measured in various natural honey samples collected from different regions in Morocco using CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs). These radionuclides were also measured in soils, plant flowers and nectar solutions corresponding to the honey samples studied. In addition, these radionuclides were measured in different imported honey samples. The measured 238U, 232Th, 222Rn and 220Rn concentrations ranged from (1.5 ± 0.1) mBq kg-1 to (10.6 ± 0.6) mBq kg-1, (1.1 ± 0.1) mBq kg-1 to (4.2 ± 0.2) mBq kg-1 , (1.5 ± 0.1) Bq kg-1 to (10.6 ± 0.6) Bq kg-1 and (1.1 ± 0.1) Bq kg-1 to (4.2 ± 0.2) Bq kg-1 for the honey samples studied, respectively. Annual 238U, 232Th and 222Rn intakes by Moroccan adults from the consumption of honey were assessed. The influence of the nature of soil and plant on the 238U and 232Th contents of the studied honey samples was investigated. These measurements were completed by an investigation of the 238U and 232 Th transfer between soils and plant flowers and that between plant flowers and honey, and also by the investigation of the influence of pollution due to different material dusts on 238U, 232Th and 222Rn in the honey samples studied. Committed equivalent doses due to the annual intake of 238U, 232Th and 222Rn were evaluated in the organs of adult members of the Moroccan rural population from the ingestion of the honey samples. The maximum total committed effective dose due to 238U, 232Th and 222Rn from the ingestion of natural honey by the Moroccan rural population was found to be equal to 0.64 Sv y-1 .

  5. Study on dependence of breakthrough time on flow rate of the carrier, gas in 229Rn adsorber bed

    Activated charcoal is a well-known adsorber of 222Rn and 220Rn gasses and its uses in mitigation of 222Rn and 220Rn in works places were reported earlier. A mitigation factor of >105 was achieved easily for 220Rn using cylindrical columns filled with activated charcoal. These studies have also reported the 222Rn breakthrough curves, breakthrough time and radon adsorption coefficient (K) for charcoal. In this paper we evaluate the effect of flow rate of the carrier gas on breakthrough time and the mitigation factor. This information is very useful in designing 220Rn migitation systems for the actual use in workplaces. The variations in breakthrough time and adsorption coefficient (K) with the flow-rate of the radon laden air in the charcoal adsorber bed were studied in detail. It was observed that the break through time was higher for lower flow rates and lower for higher flow rates. The details are presented and discussed in this paper. (author)

  6. Radon exhalation from building materials

    The new Israeli standard 5098 limits the total radiation dose of the general public from building materials to 0.45 mSv / year. A building material is accepted if it satisfies a criterion depending on the activity concentration of the natural radionuclides 226Ra, 232Th, 40K and on the Radon (222Rn) exhalation rate. As compared with existing standards, which consider only the gamma dose, this standard includes the Radon contribution allowing thereby to rigorously control the radiation dose from this practice to the general public in Israel. While the radionuclide activity may be measured via standard HPGe gamma spectroscopy, the measurement of the Radon exhalation rate is not yet standardized. According to Standard 5098 the Ministry of the Environment is responsible to recommend the optimal technique

  7. Measurement of natural radioactivity and radon exhalation rate in fly ash samples from a thermal power plant and estimation of radiation doses

    Fly ash produced by coal-burning in thermal power station has become a subject of world wide interest in recent years because of its diverse uses in construction activities and considerable economic and environmental importance. Fly ash is used in the production of bricks, sheets, cement and also in land filling etc. Indian coals used in thermal power plants are found to have high ash contents, resulting in the production of large amount of fly ash. Coal contains radionuclides including uranium (the source of inert gas radon), Th and K. Thus coal combustion results in enhanced concentration of natural radionuclides 226Ra, 232Th and 40K. Since these radionuclides concentration in fly ash plays an important role in health physics it is important to measure radionuclides concentration in fly ash. In the present work enhanced radioactivity and radon exhalation rate from fly ash samples collected from a thermal power plant of NTPC (National Thermal Power Corporation), Dadri (U.P.) India, have been measured. A high resolution gamma ray spectroscopic system has been used for the measurement of natural radioactivity (226Ra, 232Th and 40K). Gamma spectrometric measurements were carried out at Inter-University Accelerator Centre, New Delhi using a coaxial n-type HPGe detector (EG and G, ORTEC, Oak Ridge, USA). Activity concentration of 226Ra varies from 81.8 ± 2.2 to 177.3 ± 10.0 Bq kg−1 with an average value of 118.6 ± 7.4 Bq kg−1 and of 232Th from 111.6 ± 3.2 to 178.5 ± 3.9 Bq kg−1 with an average value of 147.0 ± 3.4 Bq kg−1. 40K activity was found to be below detection limit in some samples while other samples have shown potassium activity to vary from 365.9 ± 4.8 to 495.9 ± 6.2 Bq kg−1 with an average value of 352.0 ± 4.5 Bq kg−1. Surface radon exhalation rates (EA) and Mass exhalation rates (EM) in these samples were measured by “Sealed can technique” using LR-115 type II track detectors. EA is found to vary from 80.1 ± 9.3 to 242.7 ± 16.3 m

  8. Postprandial changes in the exhalation of radon from the environment

    The exhalation of radon originally inhaled from the home environment and dissolved in body fluids and tissues has been studied serially for periods of several hours in six persons. The observation of a pronounced postprandial peak in the rate of exhalation of radon shows that the similar peak observed in the exhalation of radon produced from radium in vivo results from the flushing of a reservoir in soft tissue and not from a change in the fraction lost from bone

  9. Inhaling to mitigate exhaled bioaerosols

    Edwards, David A.; Man, Jonathan C.; Brand, Peter; Katstra, Jeffrey P.; Sommerer, K.; Stone, Howard A.; Nardell, Edward; Scheuch, Gerhard

    2004-01-01

    Humans commonly exhale aerosols comprised of small droplets of airway-lining fluid during normal breathing. These “exhaled bioaerosols” may carry airborne pathogens and thereby magnify the spread of certain infectious diseases, such as influenza, tuberculosis, and severe acute respiratory syndrome. We hypothesize that, by altering lung airway surface properties through an inhaled nontoxic aerosol, we might substantially diminish the number of exhaled bioaerosol droplets and thereby provide a ...

  10. Radon exhalation from building materials used in Libya

    Radon exhalation rates have been determined for various different samples of domestic and imported building materials available in the Libyan market for home construction and interior decoration. Radon exhalation rates were measured by the sealed-can technique based on CR-39 nuclear track detectors (NTDs). The results show that radon exhalation rates from some imported building materials used as foundations and for decoration are extremely high, and these samples are the main sources of indoor radon emanation. Radium contents and annual effective doses have also been estimated. - Highlights: • Radon exhalation was measured in building materials (BM) by the can technique. • The results are mostly within the worldwide range of values found in BM samples. • Two high values of radon concentration have been observed from granite and marble. • No significant risk to the human beings due to the presence of radon in the homes

  11. Radon exhalation from building materials for decorative use.

    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. PMID:20167403

  12. Radon exhalation from building materials for decorative use

    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.

  13. Measurement and estimation of inhalation dose rates from radon, thoron and its progenies in indoor environment

    Measurement of 222Rn and 220Rn were carried out in more than 2000 houses of different types of construction in 45 locations around several parts of the country using Solid State Nuclear Track Detector (SSNTD) based dosimeter developed at the Bhabha Atomic Research Centre (BARC). This comprises of two cylindrical cups designed for optimum registration of tracks. Three detector films are used for the measurements; two in the cup modes for 222Rn and 220Rn gas estimation and one in bare mode for their progeny measurements. Detector film used is LR-115 Type-II pelliculable, of 12 μm thick cellulose nitrate. Measured geometric mean (GM) of 222Rn levels in these dwellings varied from 6.3 to 147.3 Bq/m3 with an overall GM of 23.9 Bq/m3 (GSD 1.94); while that of 220Rn varied from 5.1 to 42.8 Bq/m3 with an overall geometric mean of 14.7 Bq/m3 (GSD 1.77). Estimated total inhalation dose rates using UNSCEAR dose conversion factors, varied from 0.30 to 4.44 mSv/y with a GM of 0.97 mSv/y (GSD 1.82). It is observed that between 60 to 70% of the total inhalation dose is due to 222Rn and its progeny; while that of 222Rn and its progeny contribute to between 30-40%. (author)

  14. Radon exhalation from some finishing materials frequently used in Syria

    Building materials are one of the main radon sources in dwellings. Therefore, the determination of radon exhalation from these materials will help in prediction the existence of dwelling with potential radon risk. Ceramic tiles and marble samples were collected from Syrian local market. The correlation between radon exhalation from these materials and radium-226 content was studied. Results showed that there is no clear relation between radium content and radon exhalation rate, and the exhalation of radon did not exceed the permissible limits of American Environment Protection Agency (EPA). In addition, the additional annual dose from radon and gamma of the natural radioactivity in ceramic and marble when used as finishing materials in houses was also estimated and found to be not exceeding 20 μSv and 35 μSv from radon and gamma respectively.

  15. Radon exhalation from and diffusion in concrete

    Cylindrical test pieces of concrete are used for measurements of 222Rn exhalation rates. Except one flat end surface of a test piece, other parts of its exteriority are covered with sealant. Radon atoms can escape only through its end surface from the interior into the outside air. This treatment makes the radon transport in the concrete one dimensional phenomena. The piece is put in an airtight container. Time variations of radon concentrations in the air of the container are measured with a plane multiwire-electrode ionization chamber. From this result, the radon areal exhalation rate is deduced for the piece. Exhalation rates are measured for four pieces with different length. Then, the diffusion coefficient is obtained for radon in the concrete as (5.0 ± 1.0) x 10-8m2s-1 (a one-block method). A two-block method has been invented to obtain simultaneously values of three parameters: diffusion coefficient, porosity of concrete, and radon production rate in the pore air in the concrete. Except one end surface, the exterior is sealed preventing radon atoms from leaking out into the air. Areal exhalation rates are measured for six two-block objects linked together with pipes of different length. From these results, values of three parameters are deduced as (3.9 ± 0.5) x 10-8m2s-1, (6.9 ± 0.2) x 10-2, and (1.21 ± 0.09) x 105 atoms m-3s-1 for diffusion coefficient, porosity, and radon production rate, respectively. This value for diffusion coefficient agrees with that obtained by the one-block method within the experimental errors. The two-block method is shown to be useful to obtain the values of three parameters. Radium contents are obtained by the gamma-ray spectrometry for the concrete, and the materials used for it. The radon diffusion coefficient is measured also for the andesite used as a material of the concrete as (5.9 ± 0.3) x 10-10m2s-1. (author)

  16. Theoretical study on law of radon seepage exhalation from blasted uranium ore heap in shrinkage stope

    One dimensional differential equation for radon migration in the blasted uranium ore heap was established using radon seepage-diffusion migration theory, the formula for calculating the surface radon exhalation rate at the seepage exit in the blasted uranium ore heap was derived, and the methods for determining the relevant physical parameters were proposed. For a specific shrinkage stope, the influences of the air volume for ventilation, ore heap height and ore heap permeability on the radon exhalation rate were studied. The radon exhalation rate of the ore heap increases with the air volume for ventilation and gradually approaches its maximal value, but the growth rate decreases gradually with the increase of the air volume for ventilation. When the air volume for ventilation is small but is kept the same, the higher the ore heap is, the smaller the radon exhalation rate is. With the increase of the air volume for ventilation, the radon exhalation rate of the higher ore heap exceeds successively that of the lower ore heap, and the difference becomes larger and larger, and the higher the ore heap is, the larger the air volume for ventilation is for the radon exhalation rate to amount to its maximal value. The smaller the permeability of the ore heap is, the lower the radon exhalation rate of the heap is, the smaller the growth rate of the radon exhalation rate relative to the air volume is, and the larger the air volume for ventilation is for the radon exhalation rate to come to its maximal value. (authors)

  17. Radon exhalation in building materials of Bangalore Metropolitan, India

    Radiations ply an important role in the environment, as the world is naturally radioactive and human beings are exposed to naturally occurring background radiation. It is a fact that, radioactivity can be in the air we breathe, the soil on which we walk, the dwellings which we live and even within our bodies. This paper discusses the results of radon exhalation in building materials of Bangalore Metropolitan, India. The area of present study is Bangalore Metropolis covering an area of about 220 km2, situated at a latitude 1258 N and longitude of 7736 E with an average altitude of about 910 m above mean sea level. Solid State Nuclear Track Based CAN technique method is adopted for radon exhalation studies. The results of radon exhalation rate had a large fluctuation depending on the measurement points, samples and the building materials and the range of radon surface exhalation rates in the sites were varied from 96.0 to 725.6 mBqm-3h-1 with the arithmetic mean (AM) and geometric mean (GM) as 603.3 ± 18.6 and 578.9 ± 18.6 mBqm-3h-1 respectively. The correlation between the surface exhalation rates, mass exhalation and radon concentration in dwellings were 0.96 and 0.91 respectively. The back ground gamma radiation levels ranged from 3.7 to 5.6 mSvy-1with AM and GM as 4.7 ± 0.6 mSvy-1 respectively. The measurements showed the concentration levels are at alarming levels and demands proper control measures. The details are discussed. (author)

  18. Submarines, Spacecraft, and Exhaled Breath

    The International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled b...

  19. Comparison of Select Analytes in Exhaled Aerosol from E-Cigarettes with Exhaled Smoke from a Conventional Cigarette and Exhaled Breaths

    Gerald A. Long

    2014-10-01

    Full Text Available Exhaled aerosols were collected following the use of two leading U.S. commercial electronic cigarettes (e-cigarettes and a conventional cigarette by human subjects and analyzed for phenolics, carbonyls, water, glycerin and nicotine using a vacuum-assisted filter pad capture system. Exhaled breath blanks were determined for each subject prior to each product use and aerosol collection session. Distribution and mass balance of exhaled e-cigarette aerosol composition was greater than 99.9% water and glycerin, and a small amount (<0.06% of nicotine. Total phenolic content in exhaled e-cigarette aerosol was not distinguishable from exhaled breath blanks, while total phenolics in exhaled cigarette smoke were significantly greater than in exhaled e-cigarette aerosol and exhaled breaths, averaging 66 µg/session (range 36 to 117 µg/session. The total carbonyls in exhaled e-cigarette aerosols were also not distinguishable from exhaled breaths or room air blanks. Total carbonyls in exhaled cigarette smoke was significantly greater than in exhaled e-cigarette aerosols, exhaled breath and room air blanks, averaging 242 µg/session (range 136 to 352 µg/session. These results indicate that exhaled e-cigarette aerosol does not increase bystander exposure for phenolics and carbonyls above the levels observed in exhaled breaths of air.

  20. "EXHALE"

    Quist, Morten; Langer, Seppo W; Rørth, Mikael; Christensen, Karl Bang; Adamsen, Lis

    2013-01-01

    in a group of advanced lung cancer patients (cardiovascular and strength training, relaxation). METHODS/DESIGN: A randomized controlled trial will test the effects of the exercise intervention in 216 patients with advanced lung cancer (non-small cell lung cancer (NSCLC) stage IIIb-IV and small cell...... present randomized controlled study will provide data on the effectiveness of a supervised exercise intervention in patients receiving systemic therapy for advanced lung cancer. It is hoped that the intervention can improve physical capacity and functional level, during rehabilitation of cancer patients...

  1. 42 CFR 84.91 - Breathing resistance test; exhalation.

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Breathing resistance test; exhalation. 84.91...-Contained Breathing Apparatus § 84.91 Breathing resistance test; exhalation. (a) Resistance to exhalation...-circuit apparatus with a breathing machine as described in § 84.88, and the exhalation resistance...

  2. Nasal contribution to exhaled nitric oxide during exhalation against resistance or during breath holding

    Kharitonov, S. A.; Barnes, P. J.

    1997-01-01

    BACKGROUND: The concentration of nitric oxide (NO) is increased in the exhaled air of patients with inflammation of the airways, suggesting that this may be a useful measurement to monitor inflammation in diseases such as asthma. However, there have been concerns that exhaled NO may be contaminated by the high concentrations of NO derived from the upper airways, and that this may account for differences in reported values of exhaled NO using different techniques. A study was performed, ...

  3. Radon exhalation from granites used in Saudi Arabia.

    al-Jarallah, M

    2001-01-01

    Measurements of radon exhalation for a total of 50 selected samples of construction materials used in Saudi Arabia were taken using a radon gas analyzer. These materials included sand, aggregate, cement, gypsum, hydrated lime, ceramics and granite. It was found that the granite samples were the main source of radon emanations. A total of 32 local and imported granite samples were tested. It was found that the radon exhalation rates per unit area from these granite samples varied from not detectable to 10.6 Bq m-2 h-1 with an average of 1.3 Bq m-2 h-1. The linear correlation coefficient between emanated radon and radium content was 0.92. The normalized radon exhalation rates from 2.0 cm thick granite samples varied from not detectable to 0.068 (Bq m-2 h-1)/(Bq kg-1) with an average of 0.030 (Bq m-2 h-1)/(Bq kg-1). The average radon emanation of the granite samples was found to be 21% of the total radium concentration. Therefore, granite can be a source of indoor radon as well as external gamma-radiation from the uranium decay series. PMID:11378931

  4. Uranium distribution and radon exhalation from Brazilian dimension stones

    Amaral, P.G.Q.; Galembeck, T.M.B. [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil); Bonotto, D.M., E-mail: danielbonotto@yahoo.com.br [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil); Artur, A.C. [Departamento de Petrologia e Metalogenia, Instituto de Geociencias e Ciencias Exatas, Universidade Estadual Paulista (UNESP), Av. 24-A No. 1515, C.P. 178, CEP 13506-900, Rio Claro, Sao Paulo (Brazil)

    2012-04-15

    This paper provides evaluations of the radiometric behavior and exhalation patterns of radon gas in decorative and dimension stones explored in the Brazilian states of Minas Gerais and Espirito Santo, given the importance of determining radon gas concentrations in human-inhabited environments. A total of 10 silicate rock types were studied, featuring different petrographic/petrophysical characteristics given by seven magmatic rocks (three of which are granitic pegmatites) and three metamorphic rocks. The study, comprising radiometric data of U and monitoring of {sup 222}Rn gas exhalation, shows a strong correlation between petrographic parameters and the physical properties of rocks. U levels ranged between 2.9 and 37 ppm, revealing a good coherence between the presence and the absence of radioactive element-bearing accessory minerals for each rock type. The rate of radon exhalation from the stones is related to the petrographic/petrophysical features of each material. By comparing the {sup 222}Rn level generated by a rock to the amount effectively emanated by it, the rate of emanated gas proves to be insignificant; also, a rock that produces more Rn will not always emanate more. Simulations performed to estimate the radon levels inside residences or any given indoor environment showed that nine samples attained values below the 4 pCi/L EPA limit, whereas one was above that limit. - Highlights: Black-Right-Pointing-Pointer Integration of distinct radiometric data acquired in dimension stones. Black-Right-Pointing-Pointer Dimension stones are extensively commercialized abroad. Black-Right-Pointing-Pointer Rn exhalation above the EPA threshold limit of 4 pCi/L.

  5. Exhaled CO, a predictor of lung function?

    Fabricius, P; Scharling, H; Lokke, A;

    2007-01-01

    BACKGROUND: Smoking is associated with an accelerated loss of lung function and inhalation accelerates the decline further. Exhaled CO reflects the exposure of smoke to the lungs. AIM: To investigate whether self-reported inhalation and type of cigarette influenced the level of exhaled CO and...... whether CO could provide additional information to usual measures of smoking regarding prediction of present lung function and decline in lung function over an extended period of time. METHOD: Cigarette smokers from the Copenhagen City Heart Study with valid measures of lung function and exhaled CO; in.......001). Increasing CO levels were correlated to a lower FEV(1)%pred and to an accelerated decline in lung function. However, in multiple linear regression analyses these correlations were not significant. CONCLUSION: Inhalation and type of cigarette affects exhaled CO levels. CO measures have no predictive value...

  6. Radon Exhalation Considered in Building Material Standard

    2008-01-01

    <正>In order to investigate the relationship between radon exhalation and specific activity of natural nuclides in building material, here different kinds of samples of building materials were measured by the

  7. Submarines, spacecraft and exhaled breath.

    Pleil, Joachim D; Hansel, Armin

    2012-03-01

    Foreword The International Association of Breath Research (IABR) meetings are an eclectic gathering of researchers in the medical, environmental and instrumentation fields; our focus is on human health as assessed by the measurement and interpretation of trace chemicals in human exhaled breath. What may have escaped our notice is a complementary field of research that explores the creation and maintenance of artificial atmospheres practised by the submarine air monitoring and air purification (SAMAP) community. SAMAP is comprised of manufacturers, researchers and medical professionals dealing with the engineering and instrumentation to support human life in submarines and spacecraft (including shuttlecraft and manned rockets, high-altitude aircraft, and the International Space Station (ISS)). Here, the immediate concerns are short-term survival and long-term health in fairly confined environments where one cannot simply 'open the window' for fresh air. As such, one of the main concerns is air monitoring and the main sources of contamination are CO(2) and other constituents of human exhaled breath. Since the inaugural meeting in 1994 in Adelaide, Australia, SAMAP meetings have been held every two or three years alternating between the North American and European continents. The meetings are organized by Dr Wally Mazurek (a member of IABR) of the Defense Systems Technology Organization (DSTO) of Australia, and individual meetings are co-hosted by the navies of the countries in which they are held. An overriding focus at SAMAP is life support (oxygen availability and carbon dioxide removal). Certainly, other air constituents are also important; for example, the closed environment of a submarine or the ISS can build up contaminants from consumer products, cooking, refrigeration, accidental fires, propulsion and atmosphere maintenance. However, the most immediate concern is sustaining human metabolism: removing exhaled CO(2) and replacing metabolized O(2). Another

  8. Resonance particularity of natural radon exhalation

    Natural radon flows exhalated by rocks as a result of vibrational effects at a frequency in the range of 0-45 Hz were measured under laboratory conditions. Variations of volumetric activity of subsurface radon under natural conditions at a frequency of 16.6 Hz were determined. It was ascertained that the intensity of radon flow exhaled by rocks depends on the frequency of vibration effects. The maximum yield of radon is observed at frequencies about 16 and 32 Hz

  9. Oropharyngeal origin of markers in exhaled breath

    Marteus, Helena

    2005-01-01

    Normal NO formation in the human airways occurs primarily in the nasal airways, where it is catalyzed by inducible NO synthase (iNOS), and in the oropharyngeal tract, via as yet not fully defined pathways. This NO can be detected in exhaled breath and when inflammation is present in the airways, for example in asthma, the concentration of NO is increased. Although most studies on non-invasive measurements of airway inflammation have focused on NO in exhaled breath, there has...

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

    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 x 35.0 m area x 32.8 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 226Ra in the selected granite samples ranged from 3.8 to 94.2 Bq kg-1. The radon exhalation rate from the calculation of the 226Ra activity concentration was obtained. The radon exhalation rates were 1.31-7.86 Bq m-2h-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. (authors)

  11. Fractional exhaled nitric oxide measurement with a handheld device.

    Magori, Erhard; Hiltawsky, Karsten; Fleischer, Maximilian; Simon, Elfriede; Pohle, Roland; von Sicard, Oliver; Tawil, Angelika

    2011-06-01

    A sensing system for fractional exhaled nitric oxide (FeNO) measurement is presented, which is characterized by a compact setup and a cost potential to be made available for the patient at home. The sensing is based on the work function measurement of a phthalocyanine-type sensing material, which is shown to be sufficiently sensitive for NO(2) in the ppb range. The transducer used to measure the work function is a field effect transistor with a suspended gate electrode. Selectivity is given with respect to other breath components including typically metabolic by-products. The measurement system includes breath treatments in a simple setup, which essentially are dehumidification and a quantitative conversion of NO to NO(2) with a conversion rate of approx. 95%, using a disposable oxidation catalyst. The accomplishment of the correct exhalation maneuver and feeding of the suited portion of exhaled air to the sensor is provided by breath sampling means. The sensor is not gas consuming. This allows us to fill the measurement chamber once, instead of establishing a gas flow for the measurement. This feature simplifies the device architecture. In this paper, we report on sensor characteristics, system architecture and measurement with artificial breath-gas as well as with human breath with the device. PMID:21646688

  12. Monitoring of thorium incorporation by thoron in breath measurement: Methodology improvements and determination of burdens of workers

    Thorium body burdens were determined from thoron (220Rn) in breath measurements: decay products of expired 220Rn were collected electrostatically and their progeny were subsequently measured by alpha-spectrometry. The volume of the 38.5 litre collection chamber was optimised with respect to the breathing rate, the decay constant of thoron, the electric field geometry and strength, and the humidity of air. Calibration was achieved by means of a calibrated 228Th source. A minimum detectable activity of 45 mBq 224Ra freely emanating 220Rn at the mouth (Ra equivalent) was achieved. Five Thorotrast patients were measured and data ranged from 40 up to 150 Bq Ra equivalent, indicating an exhalation factor of about 4.0 ± 1.9% of the total 220Rn produced in the body. Data from 53 workers showed burdens up to 23 Bq (mean 5.5 Bq) of thorium. Urine bioassays of samples from the same workers yielded corresponding results. In vivo measurements revealed no result above the detection limit of 25 Bq 208Tl. (author)

  13. Radium concentration and radon exhalation measurements in the water around thermal power plants of north India

    Samples of water from different thermal power plants in northern India have been collected and analyzed for radium and radon concentration. For the measurements, α-sensitive LR-115 type II plastic track detectors are used. The radium and radon levels measured in some samples are high and thus unsafe from health point of view. Based upon the available data, the radon exhalation rates have been calculated. The radium concentration varies from 1.11 to 3.11 Bql-1 and the radon concentration varies from 10.64 to 29.78 pCil-1. The radon mass exhalation rates vary from 8.95 to 25.08 mBqkg-1hr-1 and surface exhalation rates vary from 245.21 to 690.24 mBqm-12hr-1 in different water samples. (author)

  14. Influencing effect of heat-treatment on radon emanation and exhalation characteristic of red mud

    The reuse of industrial by-products is important for members of numerous industrial sectors. However, though the benefits of reuse are evident from an economical point of view, some compounds in these materials can have a negative effect on users' health. In this study, the radon emanation and exhalation features of red mud were surveyed using heat-treatment (100–1200 °C). As a result of the 1200°C-treated samples, massic radon exhalation capacity reduced from 75 ± 10 mBq kg−1 h−1 to 7 ± 4 mBq kg−1 h−1, approximately 10% of the initial exhalation rate. To find an explanation for internal structural changes, the porosity features of the heat-treated samples were also investigated. It was found that the cumulative pore volume reduced significantly in less than 100 nm, which can explain the reduced massic exhalation capacity in the high temperature treated range mentioned above. SEM snapshots were taken of the surfaces of the samples as visual evidence for superficial morphological changes. It was found that the surface of the high temperature treated samples had changed, proving the decrement of open pores on the surface. - Highlights: • The radon exhalation depends on the heat-treatment temperature. The 1200 °C treated samples has only 10% radon exhalation of the initial. • A strong correlation was found between the porosity and the radon emanation and exhalation features. • Despite these promising results certain components can have an effect on one another, which in turn can cause harmful final structure

  15. Radon exhalation from sub-slab aggregate used in home construction in Canada

    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. (authors)

  16. Protection of occupants from exhaled infectious agents and floor material emissions in rooms with personalized and underfloor ventilation

    Cermak, Radim; Melikov, Arsen Krikor

    2007-01-01

    pollutants associated with exhaled air and floor material emissions was evaluated at various combinations of personalized and underfloor airflow rates. Compared to underfloor ventilation alone, personalized and underfloor ventilation provided excellent protection Of seated occupants from any pollution, while...... the concentration of exhaled air pollution increased in the room. The two types of personalized ventilation performed differently. Subsequent analyses of airborne infection transmission risk indicated that personalized ventilation could become a supplement to traditional methods of infection control....

  17. 42 CFR 84.123 - Exhalation valve leakage test.

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Exhalation valve leakage test. 84.123 Section 84.123 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OCCUPATIONAL SAFETY....123 Exhalation valve leakage test. (a) Dry exhalation valves and valve seats will be subjected to...

  18. Measurements of Radon Exhalation Flux and Atmospheric Radon in Uranium Mining and Processing Sites

    The Nuclear Regulatory Authority (ARN) performs an environmental monitoring of areas around the different nuclear facilities. This environmental monitoring involves a periodical sampling and analysis in the areas surrounding the operating and decommissioned facilities for the mining and milling of uranium ores. This monitoring implies the sampling and measurements of natural uranium and 226Ra levels in surface waters, sediments and ground waters in each surrounding area. Moreover, radon exhalation flux measurements from uranium mill tailings and radon concentration in air are performed. Radon exhalation rate measurement is performed by activated charcoal adsorption followed by gamma spectrometry. In the case of radon gas measurements in air, they are carried out by several methods, mainly by nuclear track detectors (Makrofol and CR-39). In this work, the results related with radon exhalation flux measurements and radon concentration in air are presented and discussed. In addition, a full description of the methods used is presented. (author)

  19. Correlation between radon exhalation and radium content in granite samples used as construction material in Saudi Arabia

    Measurements of radon exhalation for a total of 205 selected samples of construction materials used in Saudi Arabia were carried out using an active radon gas analyzer with an emanation container. It was found that granite samples were the main source of radon exhalation. The radon exhalation rates per unit area from these granite samples varied from below the minimum detection limit up to 13.1Bqm-2h-1 with an average of 1.5 +/-1.9(1σ)Bqm-2h-1. The radium contents of 27 granite samples were measured using an HPGe-based γ spectroscopy setup. The 226Ra content of the granites varied from below the minimum detection limit up to 297Bqkg-1, with an average of 83+/-73(1σ)Bqkg-1. The linear correlation coefficient between exhaled radon and radium content was found to be 0.90

  20. Measurements of exhaled nitric oxide in healthy subjects age 4 to 17 years

    Buchvald, Frederik; Baraldi, Eugenio; Carraro, Silvia;

    2005-01-01

    NO was measured in healthy subjects of 4 to 17 years according to American Thoracic Society guidelines (single breath online, exhalation flow 50 mL/s) with a chemiluminescence analyzer (NIOX Exhaled Nitric Oxide Monitoring System, Aerocrine, Sweden) in 3 European and 2 US centers. Each child performed 3...... NO in 405 children was 9.7 ppb, and the upper 95% confidence limit was 25.2 ppb. FE NO increased significantly with age, and higher FE NO was seen in children with self-reported rhinitis/conjunctivitis or hay fever. The success rate was age-dependent and improved from 40% in the children 4 years old...

  1. An Experimental Study of Human Exhalation during Breathing and Coughing in a Mixing Ventilated Room

    Liu, Li; Lia, Yuguo; Nielsen, Peter V.;

    2009-01-01

    flow rates and temperatures for breathing and coughing, respectively. Smoke visualizations are conducted to show the formation, movement and vanishing of the exhalation jets from nose and mouth separately. The transient velocity distribution generated by breathing and coughing in different places......This study investigates the characteristics of human exhalation during breathing and coughing. Experiments employing one breathing thermal manikin are conducted in a full-scale test room with a mixing ventilation system. Two artificial lungs are used to generate discontinuous airflows with specific...

  2. Continuous Exhaled Breath Analysis on the Icu

    Bos, Lieuwe D. J.; Sterk, Peter J.; Schultz, Marcus J.

    2011-09-01

    During admittance to the ICU, critically ill patients frequently develop secondary infections and/or multiple organ failure. Continuous monitoring of biological markers is very much needed. This study describes a new method to continuously monitor biomarkers in exhaled breath with an electronic nose.

  3. CONTINUOUS EXHALED BREATH ANALYSIS ON THE ICU

    During admittance to the ICU, critically ill patients frequently develop secondary infections and/or multiple organ failure. Continuous monitoring of biological markers is very much needed. This study describes a new method to continuously monitor biomarkers in exhaled breath with an electronic nose.

  4. Exhaled CO, a predictor of lung function?

    Fabricius, Peder; Scharling, Henrik; Løkke, Anders;

    2007-01-01

    whether CO could provide additional information to usual measures of smoking regarding prediction of present lung function and decline in lung function over an extended period of time. METHOD: Cigarette smokers from the Copenhagen City Heart Study with valid measures of lung function and exhaled CO; in...

  5. Exhaled nitric oxide levels in exacerbations of asthma, chronic obstructive pulmonary disease and pneumonia

    Nitric oxide is known to be present in the exhaled air of normal subjects and at higher concentrations in asthmatics. The aim of this study was to measure exhaled nitric oxide levels in patients admitted to hospital with acute exacerbations of asthma, or chronic obstructive pulmonary disease, or with pneumonia. Within 24 hours of admission exhaled nitric oxide levels were measured by a chemiluminescent analyzer in 11 patients with acute sever asthma, 19 patients with acute exacerbation of chronic obstructive pulmonary disease, and in 12 patients with pneumonia. In asthmatics measurements were made on 3 occasions, at day 1, 4, and 28 and were related to changes in peak expiratory flow rate. On admission median exhaled nitric oxide levels (range) were significantly higher in asthmatics 22 (9.3-74) parts per billion in comparison to patients with chronic obstructive pulmonary disease 10.3 (2.7-34) parts per billion; p<0.01, pneumonia 7 (4-17) parts per billion; p<0.001, and normal subjects 8.7 (5-13.3) parts per billion; p<0.001. Following treatment the asthmatics had a significant reduction in their exhaled nitric oxide levels from 22 (9.3-74) parts per billion on day 1 to 9.7 (5.7-18.3) parts per billion on day 28; p=0.005. Peak expiratory flow rate measurements increased from 200 (120-280) l/min on day 1 to 280 (150-475) l/min on day 4; p<0.05 and to 390 (150-530) l/min on day 28; p<0.01. A strong negative correlation existed between peak expiratory flow rate measurements and exhaled nitric oxide levels in asthmatics on day 28 (r=-0.70; p=0.017). Acute exacerbations of asthma are associated with increased levels of exhaled nitric oxide in contrast to exacerbations of chronic obstructive pulmonary disease and acute pneumonia. Exhaled nitric oxide may be a useful indirect marker of asthmatic airway inflammation. The differing time course of response of nitric oxide to peak flow measures suggests that these two measures are reflecting differing airway events. (author)

  6. Analysis of Exhaled Breath for Disease Detection

    Amann, Anton; Miekisch, Wolfram; Schubert, Jochen; Buszewski, Bogusław; Ligor, Tomasz; Jezierski, Tadeusz; Pleil, Joachim; Risby, Terence

    2014-06-01

    Breath analysis is a young field of research with great clinical potential. As a result of this interest, researchers have developed new analytical techniques that permit real-time analysis of exhaled breath with breath-to-breath resolution in addition to the conventional central laboratory methods using gas chromatography-mass spectrometry. Breath tests are based on endogenously produced volatiles, metabolites of ingested precursors, metabolites produced by bacteria in the gut or the airways, or volatiles appearing after environmental exposure. The composition of exhaled breath may contain valuable information for patients presenting with asthma, renal and liver diseases, lung cancer, chronic obstructive pulmonary disease, inflammatory lung disease, or metabolic disorders. In addition, oxidative stress status may be monitored via volatile products of lipid peroxidation. Measurement of enzyme activity provides phenotypic information important in personalized medicine, whereas breath measurements provide insight into perturbations of the human exposome and can be interpreted as preclinical signals of adverse outcome pathways.

  7. The clinical value of exhaled nitric oxide in asthma

    Pisi, Roberta

    2012-01-01

    Bronchial asthma is an inflammatory disease and measurement of biomarkers in exhaled breath has recently become an attractive approach to non-invasively monitor airway inflammation. In bronchial asthma, increased fractional exhaled nitric oxide (FeNO) concentration in exhaled breath has been shown to reflect the extent of eosinophilic inflammation. Moreover, the increase of FeNO levels are suppressed by inhaled corticosteroids (ICS). Therefore, monitoring of FeNO is a useful marker of inf...

  8. Measurements of fractional exhaled nitric oxide in pediatric asthma

    Youn-Soo Hahn

    2013-01-01

    Exhaled nitric oxide (NO) has been extensively investigated as a noninvasive marker of airway inflammation in asthma. The increased NO expression induced by inflammatory mediators in airways can be monitored easily in exhaled air from asthmatic children. Based on the relationship between the increased NO expression and eosinophilic airway inflammation, fractional exhaled nitric oxide (FeNO) measurements become an important adjunct for the evaluation of asthma. In addition, the availability of...

  9. Exhaled breath analysis discriminates phenotypes of acute lung injury (ALI)

    Bos, L.D.J.; Hemmes, S.N.T.; Nijsen, T.M.E.; P. J. Sterk; Schultz, M.J

    2012-01-01

    Introduction It has been postulated that the pathophysiology and clinical presentation of ALI based on pulmonary and non-pulmonary etiology represent different phenotypes1. Until now, little biological evidence on the molecular level has been presented to support this hypothesis. Exhaled air contains volatile organic compounds (VOCs), metabolites of systemic or respiratory origin. Exhaled air metabolites may differ between diseases2. Molecular profiling of exhaled air of intubated and mechani...

  10. Exhalation of {sup 131}I after radioiodine therapy: measurements in exhaled air

    Schomaecker, Klaus; Sudbrock, Ferdinand; Fischer, Thomas; Dietlein, Markus; Kobe, Carsten; Gaidouk, Mark; Schicha, Harald [University of Cologne, Clinic of Nuclear Medicine, Cologne (Germany)

    2011-12-15

    A considerable amount of radioiodine is exhaled after radioiodine therapy leading to unwanted radiation exposure through inhalation. This study focused on the concentration of radioactivity exhaled and its chemical nature. Air exhaled by 47 patients receiving {sup 131}I-iodine for different thyroid diseases (toxic goitre n=26, Graves' disease n=13, thyroid cancer n=8) was investigated with a portable constant air-flow sampler. Different chemical iodine species were collected separately (organic, elemental and aerosolic) up to 26 h after administration of the radioiodine capsule. The data approximated to a monoexponential time-activity curve when integrated over 100 h. The radioactivity in the filters was measured with a well counter at defined time points after administration. The radioactivity of {sup 131}I in the exhaled air 1 h after administration ranged from 1 to 100 kBq/m{sup 3}. Two parameters (half-life of radioiodine exhalation and time-integrated activity over 100 h) were substantially higher in patients with cancer after near-total thyroidectomy (11.8 {+-} 2.1 h and 535 {+-} 140 kBq / m{sup 3}, respectively) than in patients with hyperfunctioning thyroid tissue due to toxic adenoma (7.6 {+-} 2.5 h and 115 {+-} 27 kBq/m{sup 3}, respectively) or Graves' disease (6.4 {+-} 3.6 h and 113 {+-} 38 kBq/m{sup 3}, respectively). The percentage of radioiodine in the exhaled air in relation to radioiodine administered to the patient was between 80 ppm and 150 ppm. The fraction of organically bound radioiodine (mean value) for all time points after administration was 94-99.9%. This percentage did not depend on the type of thyroid disease. The amount of exhaled radioiodine is small but by no means negligible on the first day after administration. This is the first study to provide experimental evidence on a systematic basis that radioiodine becomes exhalable in vivo, i.e. in the patient. The mechanism of organification of orally administered radioiodine

  11. Quantum cascade laser-based sensors for the detection of exhaled carbon monoxide

    Pakmanesh, Nahid; Cristescu, Simona M.; Ghorbanzadeh, Atamalek; Harren, Frans J. M.; Mandon, Julien

    2016-01-01

    Carbon monoxide (CO) is an important biomarker as it originates in the human body from the heme (component of hemoglobin) degradation. Tunable laser absorption spectroscopy in the mid-infrared wavelength region is used for sensitive trace gas sensing of exhaled carbon monoxide (CO). Based on a quantum cascade laser emitting at 4.61 µm, two different spectroscopic methods are investigated: off-axis integrated cavity output spectroscopy (OA-ICOS) and wavelength modulation 2f/1f spectroscopy (WMS). The optical sensors integrate a slow feedback system to correct for wavelength drifts improving their stability over days. Both approaches demonstrate a high reproducibility and sensitivity during online measurements of exhaled human breath. Considering the detection limit to be the equal to the standard deviation of the background fluctuations, the noise-equivalent detection limit for both OA-ICOS and WMS is 7 ppbv (1-s averaging time), leading to a noise-equivalent absorption sensitivity of 3.1 × 10-7 cm-1 Hz-1/2, which is sufficient for measurements of exhaled CO (eCO). Collection and measurements of eCO samples were investigated, and different exhalation flow rates and breath-holding time were explored, to provide a reliable sampling method for future medical investigations.

  12. Radon-222 exhalation from Danish building materials: H + H Industri A/S results

    Andersen, Claus Erik

    1999-01-01

    rate measurements for 10 samples of Danish building materials are reported. Samples include ordinary concrete, lightweight aggregate concrete,autoclaved aerated concrete, bricks, and gypsum board. The maximum mass-specific exhalation rate is about 20 m Bq h"-"1 kg "-"1. Under consideration of the......This report describes a closed-chamber method for laboratory measurements of the rate at which radon-222 degasses (exhales) from small building material samples. The chamber is 55 L in volume and the main sample geometry is a slab of dimensions 5x30x30cm"3 . Numerical modelling is used to assess...... specific applications of the investigated building materials, the contribution to the indoor radon-222concentration in a single-family reference house is calculated. Numerical modelling is used to help extrapolate the laboratory measurements on small samples to full scale walls. Application of typical...

  13. Evaluation of Acute Exogenous Hypoxia Impact on the Fraction of Exhaled Nitric Oxide in Healthy Males

    Dimov Peter K.

    2016-04-01

    Full Text Available Introduction: Exogenous hypoxia increases ventilation and contracts the pulmonary vessels. Whether those factors change the values of nitric oxide in exhaled air has not yet been evaluated. Objective: To examine the effect of exogenous normobaric hypoxia on the values of the fraction of nitric oxide in exhaled breath (FeNO. Subjects аnd Methods: Twenty healthy non-smoker males at mean age of 25.4 (SD = 3.7 were tested. The basal FeNO values were compared with those at 7 min. and 15 min. after introducing into the hypoxic environment (hypoxic tent, imitating atmospheric air with oxygen concentration corresponding to 3200 m above sea level. Exhaled breath temperature was measured at baseline and at 10-12 min. of the hypoxic exposition. Heart rate and oxygen saturation were registered by pulse-oximetry. Results: All the subjects had FeNO values in the reference range. The mean baseline value was 14.0 ± 3.2 ppb, and in hypoxic conditions - 15.5 ± 3.8 ppb (7 min. and 15.3 ± 3.6 ppb (15 min., respectively, as the elevation is statistically significant (p = 0.011 and p = 0.008. The values of exhaled breath temperature were 33.79 ± 1.55°С and 33.87 ± 1.83°С (p = 0.70 at baseline and in hypoxic conditions, respectively. Baseline oxygen saturation in all subjects was higher than that, measured in hypoxia (96.93 ± 1.29% vs. 94.27 ± 2.53%; p < 0.001. Conclusions: Exogenous hypoxia leads to an increase of FeNO values, but does not affect the exhaled breath temperature.

  14. Study of radon exhalation from phosphogypsum plates and blocks from different origins

    Phosphogypsum is a waste of the fertilizer industry that concentrates radionuclides. In this work, the 222Rn exhalation rate from phosphogypsum plates and blocks from different origins used at dwellings construction was studied. The 222Rn exhalation rate was determined through the accumulation chamber technique with solid state nuclear track detectors (SSNTD). The effective dose for an individual living in a residence built with phosphogypsum based materials was evaluated. It also was calculated the 222Rn exhalation rate through the UNSCEAR model, from the 226Ra concentration in the materials, in order to compare the experimental results. It was evaluated the contribution of building component (paint) to the reduction of 222Rn exhalation rate. The plates and blocks were manufactured with phosphogypsum from Bunge Fertilizantes, Ultrafertil and Fosfertil. Blocks manufactured with ordinary gypsum was also evaluated. The average results obtained were 0.19 ± 0.06 Bq m-2 h-1, 1.3 ± 0.3 Bq m-2 h-1 and 0.41 ± 0.07 Bq m-2 h-1 for plates manufactured with phosphogypsum from Bunge Fertilizer, Ultrafertil and Fosfertil, respectively. For the phosphogypsum blocks the values were 0.11 ± 0.01 Bq m-2 h-1, 1.2 ± 0.6 Bq m-2 h-1, 0.47 ± 0.15 Bq m-2 h-1, for Bunge, Ultrafertil and Fosfertil. The blocks manufactured with ordinary gypsum presented average value of 0.18 ± 0.08 Bq m-2 h'-1. All phosphogypsum plates and blocks evaluated in this study presented effective dose for radon inhalation lower than the recommended value of 1mSv y-1, the annual effective dose limit for public exposure by International Commission on Radiological Protection. (author)

  15. Radon exhalation measurements in soil and rock samples of Chamaraja Nagar area, Karnataka State, India

    Natural radioactivity is widespread and omnipresent in earth's environment. The knowledge of distribution of radionuclide and radiation levels in the environment is important for assessing the effects of radiation exposure to human beings. Terrestrial radiation is due to the radionuclides present in different amounts in rocks, soils, building materials, water and atmosphere. The majority of radiation exposure of the population comes from radon, an α-radioactive, inert gas. Radon produces the main natural radiation exposure for human beings and has been recognized as carcinogenic gas. Radium and its ultimate precursor uranium are the main sources of radon. In the present study, Radon exhalation rate and Radium concentration in soil and rock samples around Chamaraja Nagar area of Karnataka state, India, are measured by SSNTD method, using can technique and LR-115 type II detectors. The radium activity in rock sample varies from 2.9 to 39.5 Bq.kg-1. Mass and Surface exhalation rate of radon in rock samples varies from 8.1 to 119.7 mBq.kg-11h-1 and 454.7 to 1787.3 mBq.m-2h-1 respectively. Radium concentration in soil samples has been found to vary from 3.6 to 34.1 Bq.kg-1 with an average value of 16.5 Bq.kg-1. The surface exhalation rate of radon 142 to 1377.3 mBq.m-2h-1. The mass exhalation rate of radon in soil samples has been found to vary from 10 to 31.4 mBq.kg-1h-1, with an average value of 19.3 mBq.kg-1h-1 and standard deviation of 7.6. (author)

  16. NO in exhaled air of asthmatic children is reduced by the leukotriene receptor antagonist montelukast

    Bisgaard, H; Loland, L; Oj, J A

    1999-01-01

    -six asthmatic children 6 to 15 yr of age completed a double-blind crossover trial of 2 wk of treatment with 5 mg montelukast once daily versus placebo. FENO was measured during single-breath exhalation at a constant flow rate of 0.1 to 0.13 L/s against a resistance of 10 kPa/L/s. Eleven children were receiving...

  17. Increased amount of nitric oxide in exhaled air of asthmatics.

    Alving, K; Weitzberg, E; Lundberg, J M

    1993-10-01

    The presence of nitric oxide (NO) in the exhaled air of humans has recently been described. We wanted to assess at what level exhaled NO originates in normal airways, and to determine whether airway inflammation induces changes in the levels of exhaled NO. Exhaled NO was continuously measured by chemiluminescence technique during normal tidal breathing through the nose or mouth, with a detection limit of 1 part per billion (ppb). Twelve control subjects were compared to eight patients with mild atopic asthma and rhinitis caused by occupational allergen. In control subjects, the major part of NO in exhaled air (up to 30 ppb) seemed to originate in the nasal airways, with only minor contribution from the lower airways and the oral cavity. However, in mild asthmatics, the level of exhaled NO during oral breathing, indicating the involvement of the lower airways, was increased 2-3 fold. Since increased production of NO in the lower airways may involve activated macrophages or neutrophils, we suggest that exhaled NO may be used to instantly monitor ongoing bronchial inflammation, at least when involving inducible NO synthase. PMID:7507065

  18. Influence of building materials process technology on radon exhalation

    The building materials were produced through changing raw material ingredient, baking temperature, pressure difference between surface and interior of building material, grain diameter etc. Experiment indicates that change of raw material ingredient ratio can obviously influence the radon exhalation from building material, followed by baking temperature; and pressure difference does not have significant influence on radon exhalation. For the factory to produce shale-brick, the radon exhalation is relatively low under the condition that coal gangue accounts for 40%-50%, the grain diameter is less than 2 mm, the baking temperature is about 960 degree C or 1 020 degree C and the pressure difference is 85 kPa. (authors)

  19. Radon exhalation and natural radionuclides level in sediment of Cauvery riverine environment

    Human beings have always been exposed to natural radiation, which derive essentially from radionuclides present in 238U series, 232Th series and singly occurring radionuclides like 40K that are present in the earth's crust. Natural radioactivity is wide spread in the earth's environment and it exists in trace levels in soil, sediment, rock, plant, water and air. Among the various geological formations, sediment plays a predominant role in aquatic radioecology and plays a role in accumulating and transporting contaminants within the geographic area. It is the basic indicator of radiological contamination in the environment. However, sediment depositions on the bottom of rivers frequently consist of sand and gravel particles, which make them particularly valuable for the building construction in Karnataka and nearby states of India. Therefore, the radionuclides concentrations and their distributions, and its associated dose rates in the river sediments should be monitored. With this objective, the radioactivity level and the radon exhalation rate were studied in Cauvery river sediments. In the present study, the systematic measurement of activity concentration of 40K, 226Ra and 232Th, and radon exhalation rate in sediment sample of Cauvery river was measured. Activity of natural radionuclides were measured by HpGe gamma ray spectrometer and radon exhalation rate was measured by 'can' technique using SSNTD (LR115, Type IT). The mean values of 40K, 226Ra and 231Th in the sediment samples were found to be 144.3 Bq kg-1, 32.0 Bq kg-1 and 58.8 Bq kg-1 respectively. The mean value of radium concentration, Surface exhalation and Mass exhalation rate are 165.2 mBq kg-1, 345.4 mBq m-1 h-1, 150.7 mBq kg-1 h-1. To assess the radiological hazard of the natural radioactivity in the samples, Annual effective dose rate, internal hazard index (Hin), external hazard index (Hex), activity utilization index (AUI), excess lifetime cancer risk (ELCR) and annual

  20. Exhaled breath condensate sampling is not a new method for detection of respiratory viruses

    Maes Piet

    2011-03-01

    Full Text Available Abstract Background Exhaled breath condensate (EBC sampling has been considered an inventive and novel method for the isolation of respiratory viruses. Methods In our study, 102 volunteers experiencing upper airway infection were recruited over the winter and early spring of 2008/2009 and the first half of the winter of 2009/2010. Ninety-nine EBCs were successfully obtained and screened for 14 commonly circulating respiratory viruses. To investigate the efficiency of virus isolation from EBC, a nasal swab was taken in parallel from a subset of volunteers. The combined use of the ECoVent device with the RTube™ allowed the registration of the exhaled volume and breathing frequency during collection. In this way, the number of exhaled viral particles per liter air or per minute can theoretically be estimated. Results Viral screening resulted in the detection of 4 different viruses in EBC and/or nasal swabs: Rhinovirus, Human Respiratory Syncytial Virus B, Influenza A and Influenza B. Rhinovirus was detected in 6 EBCs and 1 EBC was Influenza B positive. We report a viral detection rate of 7% for the EBCs, which is much lower than the detection rate of 46.8% observed using nasal swabs. Conclusion Although very promising, EBC collection using the RTube™ is not reliable for diagnosis of respiratory infections.

  1. Development of method for quantification of 222Rn exhalation ratio at radioactive waste dam and soil study as mitigator material

    The Brazilian uranium mining company (INB) processed 2.32 106 tons of uranium ore in its ore treatment unit (UTM - Caldas), located in the Pocos de Caldas plateau. During 16 years of operation, this unit discarded 2.39 106 tons of solid waste in a tailing dam, with an average activity concentration of 226Ra of 7311 ± 184 Bq kg-1. Most of the atoms of 222Rn generated from the radioactive waste of the tailing dam remain bounded to the mineral structure. However, a fraction of these atoms can be released from the mineral structure and then emanate. Reaching the porous space of the waste piles, the 222Rn moves towards the interface waste-atmosphere, exhaling into the atmosphere. The featuring properties of the 222Rn transport and the biological damage caused by its progeny transform this small chain of radionuclides into a scourge of nature. Because of that, the dry area of the tailing dam was the scope of this work. A methodology was developed for quantifying the exhalation rate of 222Rn. Moreover, the soil from its surroundings was experimentally evaluated as a cover material to reduce the exhalation of 222Rn. A collector of 222Rn was developed, being denominated 607. This collector was proved to be exact and precise after laboratory tests, when a standard for 222Rn exhalation was prepared with caldasite, an uranium ore with high concentration of 226Ra (26611 ± 581 Bq kg-1), crushed to the granulometric interval from 1.168 mm to 0.589 mm. The results of 222Rn exhalation rate using the collector 607 were not influenced by the adsorption of water steam, considering sampling periods lower than 5 days and mass of water steam lower than 7 g. Sampling for measuring 222Rn exhalation rates in the dry area of the tailing dam was carried out using the collector 607, following the experimental design established by the United States Environmental Protection Agency (US EPA). The average exhalation rate in the west part of the tailing dam was 1.30 ± 1.24 Bq m-2 s-1 in the

  2. Measurements of Fractional Exhaled Nitric Oxide in Pediatric Asthma

    Youn-Soo Hahn

    2013-10-01

    Full Text Available Exhaled nitric oxide (NO has been extensively investigated as a noninvasive marker of airway inflammation in asthma. The increased NO expression induced by inflammatory mediators in airways can be monitored easily in exhaled air from asthmatic children. Based on the relationship between the increased NO expression and eosinophilic airway inflammation, fractional exhaled nitric oxide (FeNO measurements become an important adjunct for the evaluation of asthma. In addition, the availability of portable devices makes it possible to measure FeNO more easily and frequently in the routine pediatric practice. Despite various confounding factors affecting its levels, FeNO can be applicable in diagnosing asthma, monitoring treatment response, evaluating asthma control, and predicting asthma exacerbations. Thus, although pulmonary function tests are the standard tools for objective measurements of asthmatic control, FeNO can broaden the way of asthma monitoring and supplement standard clinical asthma care guidelines.

  3. Metabolite content profiling of bottlenose dolphin exhaled breath.

    Aksenov, Alexander A; Yeates, Laura; Pasamontes, Alberto; Siebe, Craig; Zrodnikov, Yuriy; Simmons, Jason; McCartney, Mitchell M; Deplanque, Jean-Pierre; Wells, Randall S; Davis, Cristina E

    2014-11-01

    Changing ocean health and the potential impact on marine mammal health are gaining global attention. Direct health assessments of wild marine mammals, however, is inherently difficult. Breath analysis metabolomics is a very attractive assessment tool due to its noninvasive nature, but it is analytically challenging. It has never been attempted in cetaceans for comprehensive metabolite profiling. We have developed a method to reproducibly sample breath from small cetaceans, specifically Atlantic bottlenose dolphins (Tursiops truncatus). We describe the analysis workflow to profile exhaled breath metabolites and provide here a first library of volatile and nonvolatile compounds in cetacean exhaled breath. The described analytical methodology enabled us to document baseline compounds in exhaled breath of healthy animals and to study changes in metabolic content of dolphin breath with regard to a variety of factors. The method of breath analysis may provide a very valuable tool in future wildlife conservation efforts as well as deepen our understanding of marine mammals biology and physiology. PMID:25254551

  4. Ethane and n-pentane in exhaled breath are biomarkers of exposure not effect

    Gorham, Katrine A; Andersen, Mads Peter Sulbæk; Meinardi, Simone; Delfino, Ralph J; Staimer, Norbert; Tjoa, Thomas; Rowland, F Sherwood; Blake, Donald R

    2009-01-01

    The relationship of exhaled ethane and n-pentane to exhaled NO, carbonylated proteins, and indoor/outdoor atmospheric pollutants were examined in order to evaluate ethane and n-pentane as potential markers of airway inflammation and/or oxidative stress. Exhaled NO and carbonylated proteins were...... inflammation or oxidative stress....

  5. Transmission of exhaled air between occupants in rooms with personalized and underfloor ventilation

    Cermak, Radim; Melikov, Arsen Krikor

    2004-01-01

    The exposure of occupants to exhaled air was examined at two different mixing zone heights of underfloor ventilation combined with two types of personalized ventilation by means of full-scale experiments. It is assumed that the air exhaled by people is one way of transmitting respiratory diseases...... occupied zone and thus has a substantial impact on the transmission of exhaled air....

  6. Associations of Exhaled Carbon Monoxide and Fractional Exhaled Nitric Oxide with Metabolic Syndrome: A Cohort Study

    Guo, Yanjun; Ma, Jixuan; Lu, Wei; He, Jintong; Zhang, Runbo; Yuan, Jing; Chen, Weihong

    2016-01-01

    Exhaled carbon monoxide (eCO) and fractional exhaled nitric oxide (FeNO) could reflect underlying inflammatory and oxidative stresses, which play important roles in pathogenetic pathways of metabolic syndrome (MetS). However, epidemiologic evidence was limited. We conducted a study in Wuhan-Zhuhai (WHZH) cohort of 3649 community participants to investigate the association between eCO, FeNO and MetS in both cross-sectional and prospective ways. The results showed that higher eCO and FeNO were associated cross-sectionally with a higher prevalence of MetS. The multivariable-adjusted odds ratios for MetS at baseline were 1.22 (95% confidence interval [CI]: 1.11 to 1.35) associated with per log eCO and 1.14 (95% CI: 1.00 to 1.30) associated with per log FeNO. During a follow-up of 3 years, 358/2181 new developed MetS cases were identified. Compared with lowest quartile of eCO and FeNO, the multivariable-adjusted risk ratios (95% CI) for MetS were 1.48 (1.06 to 2.06) related to the highest quartile of eCO. These findings remained consistent across sex but not smoking status, eCO was only associated with MetS in non-smokers when stratified by smoking status. In conclusion, our study demonstrated that eCO and FeNO were independently and positively associated with the prevalence of MetS cross-sectionally, while only eCO was positively related with the incidence of MetS prospectively. PMID:27076211

  7. Radon exhalation of hardening concrete: monitoring cement hydration and prediction of radon concentration in construction site

    Kovler, Konstantin [National Building Research Institute, Faculty of Civil and Environmental Engineering, Technion - Israel Institute of Technology, Technion City, Haifa 32000 (Israel)]. E-mail: cvrkost@technion.ac.il

    2006-07-01

    The unique properties of radon as a noble gas are used for monitoring cement hydration and microstructural transformations in cementitious system. It is found that the radon concentration curve for hydrating cement paste enclosed in the chamber increases from zero (more accurately - background) concentrations, similar to unhydrated cement. However, radon concentrations developed within 3 days in the test chamber containing cement paste were {approx}20 times higher than those of unhydrated cement. This fact proves the importance of microstructural transformations taking place in the process of cement hydration, in comparison with cement grain, which is a time-stable material. It is concluded that monitoring cement hydration by means of radon exhalation method makes it possible to distinguish between three main stages, which are readily seen in the time dependence of radon concentration: stage I (dormant period), stage II (setting and intensive microstructural transformations) and stage III (densification of the structure and drying). The information presented improves our understanding of the main physical mechanisms resulting in the characteristic behavior of radon exhalation in the course of cement hydration. The maximum value of radon exhalation rate observed, when cement sets, can reach 0.6 mBq kg{sup -1} s{sup -1} and sometimes exceeds 1.0 mBq kg{sup -1} s{sup -1}. These values exceed significantly to those known before for cementitious materials. At the same time, the minimum ventilation rate accepted in the design practice (0.5 h{sup -1}), guarantees that the concentrations in most of the cases will not exceed the action level and that they are not of any radiological concern for construction workers employed in concreting in closed spaces.

  8. 222Rn, 220Rn and Progeny Measured in a Limestone Cave and the Associated Radiation Dose

    Concentrations of radon, thoron and the attached and unattached fractions of the short lived alpha emitting decay progeny were measured at different locations in a limestone cave by means of CR-39 and LR-115 type II solid state nuclear track detectors in order to assess the dose due to inhalation. The committed equivalent doses per hour of exposure due to the attached and unattached fractions of 218Po and 214Po were evaluated in different tissues of the respiratory tract. The influence of the activity of the attached and unattached fractions of 218Po and 214Po and the mass of the tissue on the committed equivalent dose per hour of exposure was investigated. The annual committed effective doses due to the attached and unattached fractions of 218Po and 214Po were determined. A maximum value of 1.7 mSv was found for workers spending 1 h/d during the summer months inside the cave. (author)

  9. Determination of activity of the 222-Rn and 220-Rn in the air aerosols

    The accumulation filter method at aerosol sampling stations in Bratislava was used. For the measurement of the accumulated total activity of the daughter products of the nuclides (Rn-222, Rn-220 of the U-238 and Th-232) natural decay series on the filters a low level alpha-beta proportional detector was used

  10. Development of one way entry and multiple pinholes based 222Rn - 220Rn discriminating dosimeter

    Simultaneous measurement of radon and thoron concentration in an environment is of great importance in the context of estimating correct inhalation dose and for epidemiological investigation. Track detector based cup dosimeter systems are widely used in dwellings environment for radon and thoron measurement due its cost effectiveness, portability and easy to use nature. In India, LR-115 detector based twin cup dosimeters developed by Eappen and Mayya have been used in dwelling for the last few decades for measurement of radon and thoron concentration in several places such as High Background Radiation Areas, Kerala. This dosimeter system has two cups, one exclusively for radon detection and other for both radon and thoron detection with two different entries for each cup. The cup detecting only radon uses a membrane to cut-off thoron transmission and thoron is determined using subtraction technique. However a key issue in this dosimeter system is that of arriving sometimes at a negative thoron concentration in the process of calculation. One of the reasons for this unwanted result can be attributed to the assumption of the entry of same amount of radon and thoron gas per unit time, in both cups. This assumption may not hold true sometimes, due to reasons like atmospheric turbulence. Another drawback of this dosimeter is that there is a very limited scope for optimization of radon and thoron transmission through the membrane discriminator. In this paper, we present a new design of 'Pin holes based twin cup dosimeter' with single entry and based on technique for discriminating the radon-thoron gases using multiple pinholes

  11. Analysis of international intercomparisons results organized by Japan for integrating 222Rn-220Rn detectors

    Objective: To guarantee the quality of measurements with the radon-thoron discriminative detectors of our laboratory. Methods: LD-P radon-thoron discriminative detector participated in the international intercomparison for integrating radon/thoron detectors organized by National Institute of Radiological Science (NIRS, Japan). Detectors were sent to NIRS for exposure. Radon intercomparison was conducted with radon chamber providing three levels of exposure: low, medium and high levels. Thoron intercomparison was carried out at thoron chamber, which also provided three levels of exposure: low, medium and high levels. Detectors were posted back to our laboratory for etching and analysis after exposure. Then the measured values were submitted to NIRS. Finally the reference values were informed of us. Results: The relative percent difference (RPD) between the measured value and the reference value for radon was -13.8%, -14.4% and -17.1% at low, medium and high levels respectively, and that of thoron were -14.4%, 8.9% and -3.2% at three levels respectively. Conclusions: Both radon and thoron measurement of our detectors rank as 'Category Ⅰ' in the 4th international intercomparisons for integrating radon/thoron detectors with the NIRS radon/thoron chambers. (authors)

  12. Study of the attachment between the decay products of 220Rn and monodisperse aerosols

    Attachment can be described in terms of one of two theories, viz. the diffusion theory or the kinetic theory. The diffusion theory is based on the transport of radioactive atoms by means of the process of diffusion. An attachment proportional to the radius R of the aerosol particles for the size range used in these experiments, is predicted by this theory. The kinetic theory is based on intermolecular collisions as described by the kinetic theory of gasses. This theory predicts an attachment that is proportional to R2. Both these relationships have been established by other researchers. However, the author believes that they have not taken several important parameters into consideration in their experiments, several such parameters were also not properly controlled in their experiments. In the present investigation the attachment flux for the attachment of thorium B atoms (of an approximate concentration of 4x103 atoms/cm3) to monodisperes polystyrene aerosols (of a radius from 0,5 to 2,5 μm) in the concentration range 1-30 particles/cm3, was directly measured. Steps were taken to prevent the formation of radiolytic nuclei, and all the relevant parameters were measured during the experiments. The attachment between the radioactive atoms and the aerosols was found to be directly proportional to the particle concentration N, as well as to R2. The sticking probability of atoms to a particle was found to be of the order of 0,1. The results show that the attachment was found; this was attributed to the attachment of radioactive atoms to agglomerate vapour molecules

  13. Thoron (220Rn) decay products removal in poorly ventilated environments using unipolar ionizers: Dosimetric implications

    Ionizers are proven to be effective in reducing the activity concentration of radon/thoron decay products in workplace environments. However, limited studies have been conducted on understanding the mechanism of removal and the related size dependency. This study demonstrates the feasibility of reducing the activity concentrations in small chambers and in room environments up to a factor of about 7. Field experiments in an uncontrolled ventilation area such as a thorium oxalate storage shed have also shown promising results with a possible concentration reduction by a factor of 4. However, these reductions have been necessarily associated with an increase (3-5 times) in the unattached fraction of the decay products which is a significant contributor to the lung dose. Owing to this, aspersions have been cast on the capability of the ionizers in reducing the effective dose. An attempt has been made here to estimate the effective doses over a wide range of parameters such as the initial unattached fraction, activity reduction ratio and the change in the unattached fraction, which get altered due to the use of ionizers. The study proves that for realistically achievable activity reduction ratios of about 3-5 with the employment of ionizers, the inhalation dose in workplace environments can be reduced by a factor of at least 4, as indicated by model calculations.

  14. An extensive indoor 222Rn/220Rn monitoring in North-East India

    The behaviour of ubiquitous radon (Rn222), thoron (Rn220) and their progeny in the indoor atmosphere generally reflect a complex interplay between a number of processes, the most important of which are radioactive α-decay, ventilation, attachment to aerosols and deposition on the surfaces. The present work involved a long-term (1997-2000) passive monitoring of Rn222 and Rn220 in the indoor environment of the North-Eastern region of India. This region being a zone of high seismicity, the indoor radon and thoron measurement of the region will provide a better insight and a valuable database for any study related to radon and thoron anomalies

  15. Low background counting of 222Rn, 220Rn and 219Rn with electrostatic counters

    Mong, Brian; EXO-200 Collaboration; nEXO Collaboration

    2014-09-01

    The radon counting technique based on electrostatic precipitation of progenies in gas followed by alpha spectroscopy has been applied to support the material selection programs of low background, neutrino and dark matter experiments with emphasis on EXO. An array of 8 counters operated by Laurentian University at SNOLAB and the Waste Isolation Pilot Plant have reached the sensitivity of 10 atoms/day in the uranium, thorium and actinium chains. Hardware improvements are underway to further increase the capacity and sensitivity in support of nEXO. The radon counting technique based on electrostatic precipitation of progenies in gas followed by alpha spectroscopy has been applied to support the material selection programs of low background, neutrino and dark matter experiments with emphasis on EXO. An array of 8 counters operated by Laurentian University at SNOLAB and the Waste Isolation Pilot Plant have reached the sensitivity of 10 atoms/day in the uranium, thorium and actinium chains. Hardware improvements are underway to further increase the capacity and sensitivity in support of nEXO. Supported by NSERC Project Grants ``Search for Double Beta Decay with EXO.''

  16. Protection of occupants from exhaled infectious agents and floor material emissions in rooms with personalized and underfloor ventilation

    Cermak, Radim; Melikov, Arsen Krikor

    2007-01-01

    The performance of two personalized. ventilation systems supplying air at the breathing zone was tested in conjunction with underfloor ventilation generating two different airflow patterns in a full-scale test room. Two breathing thermal manikins were used to simulate occupants. The distribution...... of pollutants associated with exhaled air and floor material emissions was evaluated at various combinations of personalized and underfloor airflow rates. Compared to underfloor ventilation alone, personalized and underfloor ventilation provided excellent protection Of seated occupants from any pollution, while...

  17. The correlations between Radon in soil gas and its exhalation and concentration in air in the southern part of Syria

    The aim of this work is to measure the concentration of the radon (222Rn) in soil air, 222Rn exhalation from soil and 222Rn in outdoor air which may have great influence on 222Rn levels in houses. 222Ra activity concentrations were also determined in soil samples. The studied areas are located in southern part of Syria. The common bed rock of this area is black and massive granite which are poor in uranium content [Jubeli Y.M., 1990. Uranium exploration in Syria. Internal Technical Report, vol. 1 (in English), vol. 2 (in Arabic), SAEC, Damascus; Technoexport (USSR), 1966. In: Ponikarov (Ed.), The Geological Map of Syria Scale: 1:200.000, Ministry of Industry, Damascus, Syria]. Results showed that the maximum measurement in all areas was 32500Bqm-3 in soil air with an exhalation rate of 9Bqm-2s-1 in Darra region and 66.43Bqm-3 of radon in open air, with 77Bqkg-1 of radium content in soil (Damascus suburb). In addition, correlations between Rn in soil and exhalation of Radon from soil and radon in houses were found in some areas (Sweda and Darra), while, no correlations were found in other studied areas. Moreover, no correlation between radon in houses and radon measurements in soil and in outdoors were found. This was attributed to the methodology used and the influence of building design and inhabitants behavior

  18. Exhaled nitric oxide measurements: clinical application and interpretation

    Taylor, D R; Pijnenburg, M W; Smith, A. D.

    2006-01-01

    The use of exhaled nitric oxide measurements (FEno) in clinical practice is now coming of age. There are a number of theoretical and practical factors which have brought this about. Firstly, FEno is a good surrogate marker for eosinophilic airway inflammation. High FEno levels may be used to distinguish eosinophilic from non‐eosinophilic pathologies. This information complements conventional pulmonary function testing in the assessment of patients with non‐specific respiratory symptoms. Secon...

  19. Exhaled carbon monoxide in asthmatics: a meta-analysis

    Huang Mao; Sun Yun; Bai Jianling; Yu Rongbin; Yao Xin; Zhang Jingying; Adcock Ian M; Barnes Peter J

    2010-01-01

    Abstract Background The non-invasive assessment of airway inflammation is potentially advantageous in asthma management. Exhaled carbon monoxide (eCO) measurement is cheap and has been proposed to reflect airway inflammation and oxidative stress but current data are conflicting. The purpose of this meta-analysis is to determine whether eCO is elevated in asthmatics, is regulated by steroid treatment and reflects disease severity and control. Methods A systematic search for English language ar...

  20. Exhalation pattern of thoron following incorporation of 224Ra

    The emanation factor (ω) of thoron was determined by means of thoron exhalation analysis as well as whole-body counting of 208Tl in 4 patients who had been injected intravenously with 224RaCl2 for treatment of Morbus Bechterew. At 5 hours after injection, ω was found to be 2.5 +- 0.3% remaining fairly constant during the period of examination (one week). (author)

  1. Exhaled nitric oxide in diagnosis and management of respiratory diseases

    Abba Abdullah

    2009-01-01

    Full Text Available The analysis of biomarkers in exhaled breath constituents has recently become of great interest in the diagnosis, treatment and monitoring of many respiratory conditions. Of particular interest is the measurement of fractional exhaled nitric oxide (FENO in breath. Its measurement is noninvasive, easy and reproducible. The technique has recently been standardized by both American Thoracic Society and European Respiratory Society. The availability of cheap, portable and reliable equipment has made the assay possible in clinics by general physicians and, in the near future, at home by patients. The concentration of exhaled nitric oxide is markedly elevated in bronchial asthma and is positively related to the degree of esinophilic inflammation. Its measurement can be used in the diagnosis of bronchial asthma and titration of dose of steroids as well as to identify steroid responsive patients in chronic obstructive pulmonary disease. In primary ciliary dyskinesia, nasal NO is diagnostically low and of considerable value in diagnosis. Among lung transplant recipients, FENO can be of great value in the early detection of infection, bronchioloitis obliterans syndrome and rejection. This review discusses the biology, factors affecting measurement, and clinical application of FENO in the diagnosis and management of respiratory diseases.

  2. Dispersal of Exhaled Air and Personal Exposure in Displacement Ventilated Rooms

    Bjørn, Erik; Nielsen, Peter Vilhelm

    2002-01-01

    from both nose and mouth is able to penetrate the breathing zone of another person standing nearby. The stratification of exhaled air breaks down if there is physical movement in the room. As movement increases, the concentration distribution in the room will move towards a fully mixed situation. The....... Numerical simulations support the experiments. Air exhaled through the mouth can lock in a thermally stratified layer, if the vertical temperature gradient in breathing zone height is sufficiently large. With exhalation through the nose, exhaled air flows to the upper part of the room. The exhalation flow......The influence of the human exhalation on flow fields, contaminant distributions, and personal exposures in displacement ventilated rooms is studied together with the effects of physical movement. Experiments are conducted in full-scale test rooms with life-sized breathing thermal manikins...

  3. Development of a practical testing procedure for the determination of radon exhalation from construction products

    The research project has confirmed that the measurement of radon exhalation from building products is possible and practicable using emission measuring chambers. Compared to conventional methodologies the measuring is closer to reality since indoor climate conditions as temperature, relative humidity and to some extent air exchange can be considered. The following topics are covered: requirements for a standardized methodology for the determination of radon exhalation from construction products, description of the methodology, description and discussion of exhalation measuring results.

  4. Effect of oral L-arginine administration on exhaled nitric oxide (no) concentration in healthy volunteers

    Ogata, Hiroshi; Yatabe, Midori; Misaka, Shingen; Shikama, Yayoi; Sato, Suguru; Munakata, Mitsuru; Kimura, Junko

    2013-01-01

    We previously reported a case of pulmonary hypertension, where the symptoms were improved by oral L-arginine (arginine) administration. Arginine may increase nitric oxide (NO) production in the pulmonary artery. Exhaled NO may reflect pulmonary artery NO production. It has been demonstrated that exhaled NO concentration is higher in patients with allergic diseases, but whether oral arginine administration alters exhaled NO is unknown. Therefore, in this study, we investigated whether oral arg...

  5. Distribution of Exhaled Contaminants and Personal Exposure in a Room using Three Different Air Distribution Strategies

    Olmedo, Inés; Nielsen, Peter V.; Adana, M. Ruiz de;

    2012-01-01

    The level of exposure to human exhaled contaminants in a room depends not only on the air distribution system but also on people’s different positions, the distance between them, people’s activity level and height, direction of exhalation, and the surrounding temperature and temperature gradient....... Human exhalation is studied in detail for different distribution systems: displacement and mixing ventilation as well as a system without mechanical ventilation. Two thermal manikins breathing through the mouth are used to simulate the exposure to human exhaled contaminants. The position and distance...

  6. Trace Analysis in End-Exhaled Air Using Direct Solvent Extraction in Gas Sampling Tubes: Tetrachloroethene in Workers as an Example

    Chris-Elmo Ziener

    2014-01-01

    Full Text Available Simple and cost-effective analytical methods are required to overcome the barriers preventing the use of exhaled air in routine occupational biological monitoring. Against this background, a new method is proposed that simplifies the automation and calibration of the analytical measurements. End-exhaled air is sampled using valveless gas sampling tubes made of glass. Gaseous analytes are transferred to a liquid phase using a microscale solvent extraction performed directly inside the gas sampling tubes. The liquid extracts are analysed using a gas chromatograph equipped, as usual, with a liquid autosampler, and liquid standards are used for calibration. For demonstration purposes, the method’s concept was applied to the determination of tetrachloroethene in end-exhaled air, which is a biomarker for occupational tetrachloroethene exposure. The method’s performance was investigated in the concentration range 2 to 20 μg tetrachloroethene/L, which corresponds to today’s exposure levels. The calibration curve was linear, and the intra-assay repeatability and recovery rate were sufficient. Analysis of real samples from dry-cleaning workers occupationally exposed to tetrachloroethene and from nonexposed subjects demonstrated the method’s utility. In the case of tetrachloroethene, the method can be deployed quickly, requires no previous experiences in gas analysis, provides sufficient analytical reliability, and addresses typical end-exhaled air concentrations from exposed workers.

  7. The correlation between exhalation from rocks and indoor concentration of 222Rn in the Sydney area

    The results of a survey of indoor 222Rn concentrations of 350 dwellings in the Sydney area are combined with measurements of 222Rn exhalation rates of principal rock types in the survey area. A linear regression is predicted which yields a positive regression coefficient of b=2.4±0.3, a constant of a=3.4±0.5, and a correlation coefficient of R2=0.15. This correlation was found to be highly significant by using three different statistical tests. The ratio of the indoor 222Rn concentrations in dwellings built on the two dominant rock types, the Wianamatta Shale and the Hawkesbury Sandstone, was found to be about 1.6. Copyright (2001) Australasian Radiation Protection Society Inc

  8. Online exhaled gas measurements for radiotherapy patients by proton transfer reaction mass spectrometry.

    Zou, Xue; Zhou, Wenzhao; Shen, Chengyin; Wang, Hongmei; Lu, Yan; Wang, Hongzhi; Chu, Yannan

    2016-08-01

    The present study assessed whether exhaled breath analysis using proton transfer reaction mass spectrometry (PTR-MS) could screen for radiation exposure. As the intensity of proton transfer reaction reagent ion H3(16)O(+) can be calculated with the intensity of H3(18)O(+), the intensity of H3(18)O(+) was monitored to observe the stability of the PTR-MS instrument during the experiment. The PTR-MS was applied for detecting the volatile organic compounds (VOCs) in the exhaled breath from 42 radiotherapy patients and other 61 patients who had not received radiotherapy. All patients were enrolled in the local cancer hospital. In the experiment, the subjects breathe slowly to the PTR-MS through a direct inlet system without any sampling bag or tube. The breath mass spectrometric data was statistically analyzed using Mann-Whitney U test and stepwise discriminant analysis to find the characteristic ions of radiation exposure. Receiver operating characteristics (ROC) analysis was applied for a combination of the characteristic ions. The PTR-MS instrument was stable as the intensity of reaction ion H3(16)O(+) was maintained in 1.1%. Through statistically analysis, we found 6 kinds of characteristic ions of radiation exposure, specifically mass-to-charge ratio (m/z) 93, m/z 41, m/z 102, m/z 79, m/z 131, and m/z 143. The sensitivity (true positive rate) and specificity (true negative rate) were 78.6% and 82.0% respectively. The integrated area under the ROC curve (AUC) was 0.869. The results in our study demonstrated the potential of the online breath tester PTR-MS as a non-invasive screening for radiation exposure. PMID:27209162

  9. Combined sensing platform for advanced diagnostics in exhaled mouse breath

    Fortes, Paula R.; Wilk, Andreas; Seichter, Felicia; Cajlakovic, Merima; Koestler, Stefan; Ribitsch, Volker; Wachter, Ulrich; Vogt, Josef; Radermacher, Peter; Carter, Chance; Raimundo, Ivo M.; Mizaikoff, Boris

    2013-03-01

    Breath analysis is an attractive non-invasive strategy for early disease recognition or diagnosis, and for therapeutic progression monitoring, as quantitative compositional analysis of breath can be related to biomarker panels provided by a specific physiological condition invoked by e.g., pulmonary diseases, lung cancer, breast cancer, and others. As exhaled breath contains comprehensive information on e.g., the metabolic state, and since in particular volatile organic constituents (VOCs) in exhaled breath may be indicative of certain disease states, analytical techniques for advanced breath diagnostics should be capable of sufficient molecular discrimination and quantification of constituents at ppm-ppb - or even lower - concentration levels. While individual analytical techniques such as e.g., mid-infrared spectroscopy may provide access to a range of relevant molecules, some IR-inactive constituents require the combination of IR sensing schemes with orthogonal analytical tools for extended molecular coverage. Combining mid-infrared hollow waveguides (HWGs) with luminescence sensors (LS) appears particularly attractive, as these complementary analytical techniques allow to simultaneously analyze total CO2 (via luminescence), the 12CO2/13CO2 tracer-to-tracee (TTR) ratio (via IR), selected VOCs (via IR) and O2 (via luminescence) in exhaled breath, yet, establishing a single diagnostic platform as both sensors simultaneously interact with the same breath sample volume. In the present study, we take advantage of a particularly compact (shoebox-size) FTIR spectrometer combined with novel substrate-integrated hollow waveguide (iHWG) recently developed by our research team, and miniaturized fiberoptic luminescence sensors for establishing a multi-constituent breath analysis tool that is ideally compatible with mouse intensive care stations (MICU). Given the low tidal volume and flow of exhaled mouse breath, the TTR is usually determined after sample collection via gas

  10. Exhaled breath analysis: physical methods, instruments, and medical diagnostics

    This paper reviews the analysis of exhaled breath, a rapidly growing field in noninvasive medical diagnostics that lies at the intersection of physics, chemistry, and medicine. Current data are presented on gas markers in human breath and their relation to human diseases. Various physical methods for breath analysis are described. It is shown how measurement precision and data volume requirements have stimulated technological developments and identified the problems that have to be solved to put this method into clinical practice. (instruments and methods of investigation)

  11. CFD modeling and image analysis of exhaled aerosols due to a growing bronchial tumor: Towards non-invasive diagnosis and treatment of respiratory obstructive diseases

    Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure variations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treat the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagrangian tracking approach were used to model respiratory airflows and aerosol dynamics. Respirations of tracer aerosols of 1 μm at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug delivery protocol

  12. CFD Modeling and Image Analysis of Exhaled Aerosols due to a Growing Bronchial Tumor: towards Non-Invasive Diagnosis and Treatment of Respiratory Obstructive Diseases

    Xi, Jinxiang; Kim, JongWon; Si, Xiuhua A.; Corley, Richard A.; Kabilan, Senthil; Wang, Shengyu

    2015-02-06

    Diagnosis and prognosis of tumorigenesis are generally performed with CT, PET, or biopsy. Such methods are accurate, but have the limitations of high cost and posing additional health risks to patients. In this study, we introduce an alternative computer aided diagnostic tool that can locate malignant sites caused by tumorigenesis in a non-invasive and low-cost way. Our hypothesis is that exhaled aerosol distribution is unique to lung structure and is sensitive to airway structure vari-ations. With appropriate approaches, it is possible to locate the disease site, determine the disease severity, and subsequently formulate a targeted drug delivery plan to treat the disease. This study numerically evaluated the feasibility of the proposed breath test in an image-based lung model with varying pathological stages of a bronchial squamous tumor. Large eddy simulations and a Lagran-gian tracking approach were used to model respiratory airflows and aerosol dynamics. Respira-tions of tracer aerosols of 1 µm at a flow rate of 20 L/min were simulated, with the distributions of exhaled aerosols recorded on a filter at the mouth exit. Aerosol patterns were quantified with multiple analytical techniques such as concentration disparity, spatial scanning and fractal analysis. We demonstrated that a growing bronchial tumor induced notable variations in both the airflow and exhaled aerosol distribution. These variations became more apparent with increasing tumor severity. The exhaled aerosols exhibited distinctive pattern parameters such as spatial probability, fractal dimension, and multifractal spectrum. Results of this study show that morphometric measures of the exhaled aerosol pattern can be used to detect and monitor the pathological states of respiratory diseases in the upper airway. The proposed breath test also has the potential to locate the site of the disease, which is critical in developing a personalized, site-specific drug de-livery protocol.

  13. Primarily nasal origin of exhaled nitric oxide and absence in Kartagener's syndrome.

    Lundberg, J O; Weitzberg, E; Nordvall, S L; Kuylenstierna, R; Lundberg, J M; Alving, K

    1994-08-01

    The exact origin of nitric oxide (NO) in exhaled air is not known. We wanted to further investigate at what site exhaled NO is produced and to determine whether children with Kartagener's syndrome exhibited altered levels of exhaled NO. NO was measured by chemiluminescence technique in air sampled directly from the nose and in normally exhaled air of four children (2.5-13 years old) with Kartagener's syndrome, 20 healthy children, four healthy adults, and four conscious tracheostomized adults. NO was almost absent (98% reduced) in air sampled directly from the nose in four children with Kartagener's syndrome (4 +/- 1 parts per billion (ppb)), compared to age-matched controls (221 +/- 14 (ppb)). Tracheostomized adult subjects had considerably higher NO values in nasally (22 +/- 3 ppb) and orally (14 +/- 2 ppb) exhaled air, compared to levels in air exhaled through the tracheostomy (2 +/- 0 ppb). Treatment with intranasal corticosteroids for 14 days, or with antibiotics for 1 week, did not affect exhaled NO. These results clearly show that, basically, all NO in exhaled air of healthy subjects originates from the upper respiratory tract, with only a minor contribution from the lower airways. Furthermore, the absence of nasal NO in children with Kartagener's syndrome could be of use as a simple noninvasive diagnostic test. PMID:7957837

  14. Reduction in exhaled nitric oxide immediately after methacholine challenge in asthmatic children

    Piacentini, G; Bodini, A; Peroni, D; Del Giudice, M M.; Costella, S; Boner, A

    2002-01-01

    Background: The measurement of exhaled nitric oxide (NO) has recently been proposed as a useful technique for the evaluation of airway inflammation in asthma. The purpose of this study was to determine the effect of methacholine bronchial provocation on the levels of exhaled NO in asthmatic children. Method: Exhaled NO was measurement immediately before and after methacholine provocation in 51 children with mild to moderate asthma. Results: A significant decrease occurred in the level of exhaled NO (p<0.0001) after methacholine bronchial provocation which was not correlated with the percentage fall in forced expiratory volume in 1 second (FEV1). Conclusions: The methacholine test should not be used immediately before measurement of exhaled NO in children with asthma. PMID:12200520

  15. Indoor radon and its profile: a case study in Bangalore city, India

    The natural radioactivity gives rise to internal and external indoor exposure. The external exposure is caused by gamma radiation originating from the members of the 238U, 232Th decay series and from 40K. The internal radiation exposure mainly affecting the respiratory tract is caused by the short-lived daughter products of radon, which are exhaled from the construction material into the room air. The area of present study is Bangalore City. The common rocks are pink, grey and porphyries gneisses with large feldspars and black dolerite. An attempt has been made to study the 222Rn and 220Rn levels in different volume rooms for the environment of Bangalore city, India. Solid State Nuclear Track Detector based dosimeters were used for the measurement of 222Rn and 220Rn. Rooms of the dwellings were carefully categorized on the basis of interior volume such as 30 - 200 m3 further they were classified into four groups as 30-40 m3, 64-75 m3, 80-100 m3 and 110- 200 m3. The measured arithmetic mean concentrations of 222Rn and 220Rn for a period of 5 years were 81.06 and 57.54, 54.09 and 31.00, 43.36 and 22.63, 30.68 and 15.74,16.67 and 11.08 respectively. The inhalation dose rate in higher volume rooms varied from 0.77 to 3.24 mSvy-1 with an AM as 1.35 ± 0.03 and in lower volume rooms they were ranged from 2.24 to 3.83 mSvy1 with an AM as 2.94 ± 0.14. Higher concentrations and dose rates were observed in smaller volume room and the lower concentration were observed in bigger volume rooms irrespective of the seasons. Results are discussed in detail. (author)

  16. Exhalation velocity of radon-222 of Dutch building materials and the influence of paint systems

    In order to achieve a better insight concerning the source terms of radon in the Dutch dwelling in the framework of the RENA-programme an investigation has been performed into the exhalation velocity of radon-222 from building materials. From this investigation it turned out that the ventilation factor does not have any influence upon the exhalation velocity, neither an influence of alteration of air pressure could be demonstrated. The influence of air humidity upon the exhalation velocity showed a twofold picture; for gypsum a linear increase of the exhalation velocity with vapour pressure was found, while for concrete a linear decrease with vapour pressure was observed. Further it has been investigated in how far paint systems diminish the exhalation velocity of the Rn-222 from gypsum and concrete. Acryl paints, mostly used in the Dutch dwelling, did not show a decrease of the exhalation velocity and structure paints did even cause an increase of the exhalation velocity. Other types of paint based on chlorous rubber, epoxy resins and poly-urethane, in contrast, showed a clear reduction. From these those based on poly-urethane showed the largest reduction (60-75%) at a double sided treatment of the wall. With the help of a mathematical modelling of the exhalation estimations have been made of the exhalation velocity of Rn-222 at single sided treatment of a wall and for the exhalation velocity of Rn-220. For the fore mentioned poly-urethane-paints this yelds, at an estimate, a reduction of respectively 90-95% and 100%. (author). 40 refs.; 15 figs.; 8 tabs

  17. Exhaled nitric oxide in stable chronic obstructive pulmonary disease

    The objective of the study was to test the hypothesis that fraction of exhaled nitric oxide (FENO) is elevated in nonsmoking subjects with stable chronic obstructive pulmonary disease (COPD) and compare it with the results in patients with asthma and a control population. Pulmonology Clinic at a University Hospital. Twenty five control subjects, 25 steroid naive asthmatics and 14 COPD patients were studied. All the patients were nonsmokers and stable at the time of the study. All subjects completed a questionnaire and underwent spirometry. Exhaled nitric oxide was measured online by chemiluminescence, using single-breath technique. All the study subjects were males. Subjects with stable COPD had significantly higher values of FENO than controls (56.54+ - 28.01 vs 22.00 + -6.69; P =0.0001) but lower than the subjects with asthma (56.54+ - 28.01 vs 84.78+ - 39.32 P 0.0285). The FENO values in COPD subjects were inversely related to the FEV 1 /FVC ratio. There was a significant overlap between the FENO values in COPD and the control subjects. There is a significant elevation in FENO in patients with stable COPD, but the elevation is less than in asthmatic subjects. Its value in clinical practice may be limited by the significant overlap with control subjects. (author)

  18. Exhaled nitric oxide in stable chronic obstructive pulmonary disease

    Beg Mohammed

    2009-01-01

    Full Text Available Study Objective : The objective of the study was to test the hypothesis that fraction of exhaled nitric oxide (FENO is elevated in nonsmoking subjects with stable chronic obstructive pulmonary disease (COPD and compare it with the results in patients with asthma and a control population. Design : Cross-sectional study. Materials and Methods : Pulmonology Clinic at a University Hospital. Twenty five control subjects, 25 steroid naοve asthmatics and 14 COPD patients were studied. All the patients were nonsmokers and stable at the time of the study. All subjects completed a questionnaire and underwent spirometry. Exhaled nitric oxide was measured online by chemiluminescence, using single-breath technique. Results : All the study subjects were males. Subjects with stable COPD had significantly higher values of FENO than controls (56.54±28.01 vs 22.00±6.69; P =0.0001 but lower than the subjects with asthma (56.54±28.01 vs 84.78±39.32 P = 0.0285.The FENO values in COPD subjects were inversely related to the FEV 1 /FVC ratio. There was a significant overlap between the FENO values in COPD and the control subjects. Conclusion : There is a significant elevation in FENO in patients with stable COPD, but the elevation is less than in asthmatic subjects. Its value in clinical practice may be limited by the significant overlap with control subjects.

  19. Chemiresistive Electronic Nose toward Detection of Biomarkers in Exhaled Breath.

    Moon, Hi Gyu; Jung, Youngmo; Han, Soo Deok; Shim, Young-Seok; Shin, Beomju; Lee, Taikjin; Kim, Jin-Sang; Lee, Seok; Jun, Seong Chan; Park, Hyung-Ho; Kim, Chulki; Kang, Chong-Yun

    2016-08-17

    Detection of gas-phase chemicals finds a wide variety of applications, including food and beverages, fragrances, environmental monitoring, chemical and biochemical processing, medical diagnostics, and transportation. One approach for these tasks is to use arrays of highly sensitive and selective sensors as an electronic nose. Here, we present a high performance chemiresistive electronic nose (CEN) based on an array of metal oxide thin films, metal-catalyzed thin films, and nanostructured thin films. The gas sensing properties of the CEN show enhanced sensitive detection of H2S, NH3, and NO in an 80% relative humidity (RH) atmosphere similar to the composition of exhaled breath. The detection limits of the sensor elements we fabricated are in the following ranges: 534 ppt to 2.87 ppb for H2S, 4.45 to 42.29 ppb for NH3, and 206 ppt to 2.06 ppb for NO. The enhanced sensitivity is attributed to the spillover effect by Au nanoparticles and the high porosity of villi-like nanostructures, providing a large surface-to-volume ratio. The remarkable selectivity based on the collection of sensor responses manifests itself in the principal component analysis (PCA). The excellent sensing performance indicates that the CEN can detect the biomarkers of H2S, NH3, and NO in exhaled breath and even distinguish them clearly in the PCA. Our results show high potential of the CEN as an inexpensive and noninvasive diagnostic tool for halitosis, kidney disorder, and asthma. PMID:27456161

  20. Gas analysis of human exhalation by tunable diode laser spectroscopy

    Stepanov, Eugene V.; Moskalenko, Konstantin L.

    1993-02-01

    Results of the application of a tunable diode laser (TDL) to determining the trace gas components of human exhalation are presented. The analyzer is specially developed to measure both carbon oxides (CO and CO2) in expired air. A few results illuminating possible applications of TDLs in high-sensitivity medical diagnostics have been obtained. For nonsmokers, expired concentrations of CO are slightly higher than those in inhaled air. The specific surplus value seems to be independent of the ambient atmospheric CO content. The surplus CO content increases by more than an order of magnitude just after intensive exercises, e.g., jogging. For smokers, the pharmacokinetic of abundant CO removal from the organism could be investigated by this technique, which provides quick and reliable measurements of smoking status. Breath-holding synchronous measurements of CO and CO2 in exhalation demonstrate behavior that is different with breath-holding time. The method seems useful for the investigation of phenomena such as molecular pulmonary diffusion through the alveolar-capillary membrane and an organism's adaptation to oxygen shortage. Prospects for the development and application of diode laser spectroscopy to trace gas analysis in medicine are also discussed.

  1. Development and Performance Evaluation of an Exhaled-Breath Bioaerosol Collector for Influenza Virus.

    McDevitt, James J; Koutrakis, Petros; Ferguson, Stephen T; Wolfson, Jack M; Fabian, M Patricia; Martins, Marco; Pantelic, Jovan; Milton, Donald K

    2013-01-01

    The importance of the aerosol mode for transmission of influenza is unknown. Understanding the role of aerosols is essential to developing public health interventions such as the use of surgical masks as a source control to prevent the release of infectious aerosols. Little information is available on the number and size of particles generated by infected persons, which is partly due to the limitations of conventional air samplers, which do not efficiently capture fine particles or maintain microorganism viability. We designed and built a new sampler, called the G-II, that collects exhaled breath particles that can be used in infectivity analyses. The G-II allows test subjects to perform various respiratory maneuvers (i.e. tidal breathing, coughing, and talking) and allows subjects to wear a mask or respirator during testing. A conventional slit impactor collects particles > 5.0 μm. Condensation of water vapor is used to grow remaining particles, including fine particles, to a size large enough to be efficiently collected by a 1.0 μm slit impactor and be deposited into a buffer-containing collector. We evaluated the G-II for fine particle collection efficiency with inert particle aerosols and evaluated infective virus collection using influenza A virus aerosols. Testing results showed greater than 85% collection efficiency for particles greater than 50nm and influenza virus collection comparable with a reference SKC BioSampler®. The new design will enable determination of exhaled infectious virus generation rate and evaluate control strategies such as wearing a surgical type mask to prevent the release of viruses from infected persons. PMID:23418400

  2. Study of radon exhalation from phosphogypsum plates and blocks from different origins; Estudo da exalacao de radonio em placas e tijolos de fosfogesso de diferentes procedencias

    Costa, Lucas Jose Pereira da

    2011-07-01

    Phosphogypsum is a waste of the fertilizer industry that concentrates radionuclides. In this work, the {sup 222}Rn exhalation rate from phosphogypsum plates and blocks from different origins used at dwellings construction was studied. The {sup 222}Rn exhalation rate was determined through the accumulation chamber technique with solid state nuclear track detectors (SSNTD). The effective dose for an individual living in a residence built with phosphogypsum based materials was evaluated. It also was calculated the {sup 222}Rn exhalation rate through the UNSCEAR model, from the {sup 226}Ra concentration in the materials, in order to compare the experimental results. It was evaluated the contribution of building component (paint) to the reduction of {sup 222}Rn exhalation rate. The plates and blocks were manufactured with phosphogypsum from Bunge Fertilizantes, Ultrafertil and Fosfertil. Blocks manufactured with ordinary gypsum was also evaluated. The average results obtained were 0.19 {+-} 0.06 Bq m-2 h-1, 1.3 {+-} 0.3 Bq m{sup -2} h{sup -1} and 0.41 {+-} 0.07 Bq m{sup -2} h{sup -1} for plates manufactured with phosphogypsum from Bunge Fertilizer, Ultrafertil and Fosfertil, respectively. For the phosphogypsum blocks the values were 0.11 {+-} 0.01 Bq m{sup -2} h-1, 1.2 {+-} 0.6 Bq m{sup -2} h{sup -1}, 0.47 {+-} 0.15 Bq m{sup -2} h{sup -1}, for Bunge, Ultrafertil and Fosfertil. The blocks manufactured with ordinary gypsum presented average value of 0.18 {+-} 0.08 Bq m{sup -2} h'-{sup 1}. All phosphogypsum plates and blocks evaluated in this study presented effective dose for radon inhalation lower than the recommended value of 1mSv y{sup -1}, the annual effective dose limit for public exposure by International Commission on Radiological Protection. (author)

  3. Leukotrienes in exhaled breath condensate and fractional exhaled nitric oxide in workers exposed to TiO2 nanoparticles.

    Pelclova, Daniela; Zdimal, Vladimir; Kacer, Petr; Fenclova, Zdenka; Vlckova, Stepanka; Komarc, Martin; Navratil, Tomas; Schwarz, Jaroslav; Zikova, Nadezda; Makes, Otakar; Syslova, Kamila; Belacek, Jaroslav; Zakharov, Sergey

    2016-01-01

    Human health data regarding exposure to nanoparticles are extremely scarce and biomonitoring of exposure is lacking in spite of rodent pathological experimental data. Potential markers of the health-effects of engineered nanoparticles were examined in 30 workers exposed to TiO2 aerosol, 22 office employees of the same plant, and 45 unexposed controls. Leukotrienes (LT) B4, C4, E4, and D4 were analysed in the exhaled breath condensate (EBC) and urine via liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). Fractional exhaled nitric oxide (FeNO) and spirometry was also measured. The median particle number concentration of the aerosol in the production ranged from 1.98  ×  10(4) to 2.32  ×  10(4) particles cm(-3); about 80% of the particles were  spirometry significant impairment in the workers was seen only for %VCIN and %PEF (both p  Spirometry was not sensitive enough. PMID:27356965

  4. Hydrogen peroxide in exhaled breath condensate: A clinical study

    C Nagaraja

    2012-01-01

    Full Text Available Objectives: To study the ongoing inflammatory process of lung in healthy individuals with risk factors and comparing with that of a known diseased condition. To study the inflammatory response to treatment. Background: Morbidity and mortality of respiratory diseases are raising in trend due to increased smokers, urbanization and air pollution, the diagnosis of these conditions during early stage and management can improve patient′s lifestyle and morbidity. Materials and Methods: One hundred subjects were studied from July 2010 to September 2010; the level of hydrogen peroxide concentration in exhaled breath condensate was measured using Ecocheck. Results: Of the 100 subjects studied, 23 were healthy individuals with risk factors (smoking, exposure to air pollution, and urbanization; the values of hydrogen peroxide in smokers were 200-2220 nmol/l and in non-smokers 340-760 nmol/l. In people residing in rural areas values were 20-140 nmol/l in non-smokers and 180 nmol/l in smokers. In chronic obstructive pulmonary disease cases, during acute exacerbations values were 540-3040 nmol/l and 240-480 nmol/l following treatment. In acute exacerbations of bronchial asthma, values were 400-1140 nmol/l and 100-320 nmol/l following treatment. In cases of bronchiectasis, values were 300-340 nmol/l and 200-280 nmol/l following treatment. In diagnosed pneumonia cases values were 1060-11800 nmol/l and 540-700 nmol/l following treatment. In interstitial lung diseases, values ranged from 220-720 nmol/l and 210-510 nmol/l following treatment. Conclusion: Exhaled breath condensate provides a non-invasive means of sampling the lower respiratory tract. Collection of exhaled breath condensate might be useful to detect the oxidative destruction of the lung as well as early inflammation of the airways in a healthy individual with risk factors and comparing the inflammatory response to treatment.

  5. Impact of structural parameters on the radon exhalation of building materials: Preliminary study

    Samples of mortar and sand-lime pieces with different percentages of fly ash are hardened at different relative humidities. The porosity distribution, the moisture and the radon exhalation of these samples are determined. Based on the data of the above-mentioned analyses, the thickness of the adsorbed water layer in the water-filled pores is estimated. The correlation between the structural parameters and the radon exhalation is investigated. If the radon exhalation process can be modelled, the radiation risk of applying fly ash in building materials can be controlled or reduced. The results do not yet show a clear indication. The applied methods have to be considered in more detail

  6. CFD Analysis of the Human Exhalation Flow using Different Boundary Conditions and Ventilation Strategies

    Villafruela, J.M.; Olmedo, Inés; Ruiz de Adana, M.;

    2013-01-01

    different environmental conditions and to validate whether a steady boundary condition of the exhalation flow may simulate human breathing in an effective and accurate way. The results show a very good agreement of the numerical results obtained for Test a and the experimental data. This fact confirms the...... use of numerical simulation as a powerful tool to predict the contaminant distribution exhaled by a human. The numerical tests with steady boundary conditions for the exhalation flow require a transitory resolution procedure and the predictions provided by these models display some discrepancies with...

  7. The lung cancer breath signature: a comparative analysis of exhaled breath and air sampled from inside the lungs

    Capuano, Rosamaria; Santonico, Marco; Pennazza, Giorgio; Ghezzi, Silvia; Martinelli, Eugenio; Roscioni, Claudio; Lucantoni, Gabriele; Galluccio, Giovanni; Paolesse, Roberto; di Natale, Corrado; D'Amico, Arnaldo

    2015-11-01

    Results collected in more than 20 years of studies suggest a relationship between the volatile organic compounds exhaled in breath and lung cancer. However, the origin of these compounds is still not completely elucidated. In spite of the simplistic vision that cancerous tissues in lungs directly emit the volatile metabolites into the airways, some papers point out that metabolites are collected by the blood and then exchanged at the air-blood interface in the lung. To shed light on this subject we performed an experiment collecting both the breath and the air inside both the lungs with a modified bronchoscopic probe. The samples were measured with a gas chromatography-mass spectrometer (GC-MS) and an electronic nose. We found that the diagnostic capability of the electronic nose does not depend on the presence of cancer in the sampled lung, reaching in both cases an above 90% correct classification rate between cancer and non-cancer samples. On the other hand, multivariate analysis of GC-MS achieved a correct classification rate between the two lungs of only 76%. GC-MS analysis of breath and air sampled from the lungs demonstrates a substantial preservation of the VOCs pattern from inside the lung to the exhaled breath.

  8. Markers of oxidative stress in exhaled breath of workers exposed to iron oxide nanoparticles are elevated

    Pelclová, D.; Fenclová, Z.; Navrátil, Tomáš; Vlčková, Š.; Syslová, K.; Kuzma, Marek; Ždímal, Vladimír; Schwarz, Jaroslav; Pušman, Jan; Zíková, Naděžda; Zakharov, S.; Machajová, M.; Kačer, P.

    2014-01-01

    Roč. 7, Suppl. 1 (2014), s. 69-70. ISSN 1337-6853 Institutional support: RVO:61388971 ; RVO:61388955 ; RVO:67985858 Keywords : oxidative stress * exhaled breath * nanoparticles Subject RIV: CF - Physical ; Theoretical Chemistry

  9. Standardization of exhaled breath condensate (EBC) collection using a feedback regulated breathing pattern

    Collection of exhaled breath condensate (EBC) fluid by cooling of expired breath is a potentially valuable approach for the detection of biomarkers associated with disease or exposure to xenobiotics. EBC is generally collected using unregulated breathing patterns, perceived to el...

  10. Experimental and Numerical Investigation of Effect of Air Stability on Exhaled Air Dispersion

    Xu, Chunwen; Gong, Guangcai; Nielsen, Peter Vilhelm;

    2014-01-01

    studies. As the thermal stratification under displacement ventilation blocks the vertical movement of exhaled air, the exhaled contaminant may be trapped between temperature stratifications. As the dispersion of contaminant is closely related to the health of human indoors, the temperature structure......As more and more investigations have reported the influence of thermal stratification indoors on contaminant dispersion, this paper focuses on investigating this phenomenon from the perspective of air stability which is defined in accordance with atmospheric stability. One breathing thermal manikin...

  11. High-sensitivity sensor of gases based on IR tunable diode lasers for human exhalation monitoring

    Moskalenko, Konstantin L.; Nadezhdinskii, Alexander I.; Stepanov, Eugene V.

    1991-06-01

    Results on tunable diode laser spectroscopy applications in analysis of human expiration are presented. Carbon monoxide concentrations in exhaled air of several non-smoking adults were measured with high sensitivity. Obtained CO contents slightly exceed atmosphere level and correlate with it. Simultaneous measurements of carbon monoxide and carbon dioxide were carried out using single diode laser generated at 4.7 microns. Dependences of their concentration in exhaled air on breath-holding time were investigated.

  12. Effects of immersion in cool water on lung-exhaled nitric oxide at rest and during exercise

    Pendergast, D. R.; Krasney, J. A.; DeRoberts, D.; Farhi, L. E. (Principal Investigator)

    1999-01-01

    Lung nitric oxide (NO) has been postulated to relax airway and vascular smooth muscle at rest and during exercise. As a cold environment is a common cause of respiratory distress, lung exhaled NO was measured during skin and core body cooling at rest and during a progressive cycle exercise. Ten healthy male subjects were immersed in water at a water temperature (Tw) which was thermal neutral (35 degrees C) at 30 degrees C Tw, at which only skin temperature is decreased; and at 20 degrees C Tw, at which the core temperature is decreased (0.05 degrees C). At rest, V(O), and V(E) increased while exhaled NO concentration [NO] and the rate of expiration of NO (V(NO)) decreased with decreased Tw. V(O2) and ventilation (V(E)) increased with workload (W) and the values at all Tw were not different, whereas, [NO] decreased with W and the values during exercise were progressively less at all Ws as Tw declined. These results indicate that lung NO output is reduced in a graded fashion during body cooling at rest and during exercise. This suggests that lower lung NO may contribute to airway obstruction in cold environments and NO may contribute to regulation of lung heat and water exchange.

  13. Are exhaled nitric oxide measurements using the portable NIOX MINO repeatable?

    Raza Abid

    2010-04-01

    Full Text Available Abstract Background Exhaled nitric oxide is a non-invasive marker of airway inflammation and a portable analyser, the NIOX MINO (Aerocrine AB, Solna, Sweden, is now available. This study aimed to assess the reproducibility of the NIOX MINO measurements across age, sex and lung function for both absolute and categorical exhaled nitric oxide values in two distinct groups of children and teenagers. Methods Paired exhaled nitric oxide readings were obtained from 494 teenagers, aged 16-18 years, enrolled in an unselected birth cohort and 65 young people, aged 6-17 years, with asthma enrolled in an interventional asthma management study. Results The birth cohort participants showed a high degree of variability between first and second exhaled nitric oxide readings (mean intra-participant difference 1.37 ppb, 95% limits of agreement -7.61 to 10.34 ppb, although there was very close agreement when values were categorised as low, normal, intermediate or high (kappa = 0.907, p Conclusions The reproducibility of exhaled nitric oxide is poor for absolute values but acceptable when values are categorised as low, normal, intermediate or high in children and teenagers. One measurement is therefore sufficient when using categorical exhaled nitric oxide values to direct asthma management but a mean of at least two measurements is required for absolute values.

  14. New method for determination of trihalomethanes in exhaled breath: Applications to swimming pool and bath environments

    A method for the estimation of the human intake of trihalomethanes (THMs), namely chloroform, bromodichloromethane, dibromochloromethane and bromoform, during showering and bathing is reported. The method is based on the determination of these compounds in exhaled breath that is collected by solid adsorption on Tenax using a device specifically designed for this purpose. Instrumental measurements were performed by automatic thermal desorption coupled to gas chromatography with electron capture detection. THMs in exhaled breath samples were determined during showering and swimming pool attendance. The levels of these compounds in indoor air and water were also determined as reference for interpretation of the exhaled breath results. The THM concentrations in exhaled breath of the volunteers measured before the exposure experiments showed a close correspondence with the THMs levels in indoor air where the sampler was located. Limits of detection in exhaled breath were dependent on THM analytes and experimental sites. They ranged between 170 and 710 ng m-3 in the swimming pool studies and between 97 and 460 ng m-3 in the showering studies. Application of this method to THMs determination during showering and swimming pool activities revealed statistically significant increases in THMs concentrations when comparing exhaled breath before and after exposure.

  15. An intercomparison done at NIRS, Japan on continuous monitors for measuring ²²⁰Rn concentration.

    Sorimachi, Atsuyuki; Janik, Miroslaw; Tokonami, Shinji; Ishikawa, Tetsuo

    2016-01-01

    An intercomparison for continuous monitors that measure thoron ((220)Rn) concentration was carried out using a (220)Rn chamber of National Institute of Radiological Sciences (NIRS), Japan; eleven (220)Rn monitors (four types) from nine laboratories were evaluated. The (220)Rn detection principle was the same for the eleven instruments and one reference instrument, which were commercially available silicon semiconductor detectors using an electrostatic collection method. The intercomparison results showed that there was a negative deviation of more than 30% in measured (220)Rn concentrations given by the laboratories relative to the reference values, which were obtained by making a decay-correction during the travel of (220)Rn through the sampling assembly (sample tube, filter and drying unit) and using a calibration factor. In order to elucidate the reason for this and then to investigate factors that affect the (220)Rn concentration measured with the monitors. As a result, it was necessary to make the decay-correction, in particular, when using a drying unit with a large inner volume and to use the calibration factor in order to better estimate the (220)Rn concentration. It was also found to be better to determine a calibration factor inherent to an individual monitor, because the calibration factor values ranged from 0.75 to 2.32, depending on the flow rate of the monitor pump (0.37-1.02 L min(-1)). It was concluded from this study that a periodical calibration of the monitor and a check of the monitor flow rate during measurements are necessary to maintain a consistent quality level of the (220)Rn measurement. PMID:26497806

  16. Environmental Effects on Fractional Exhaled Nitric Oxide in Allergic Children

    Stefania La Grutta

    2012-01-01

    Full Text Available Fractional exhaled nitric oxide (FeNO is a non-invasive marker of airway inflammation in asthma and respiratory allergy. Environmental factors, especially indoor and outdoor air quality, may play an important role in triggering acute exacerbations of respiratory symptoms. The authors have reviewed the literature reporting effects of outdoor and indoor pollutants on FeNO in children. Although the findings are not consistent, urban and industrial pollution—mainly particles (PM2.5 and PM10, nitrogen dioxide (NO2, and sulfur dioxide (SO2—as well as formaldehyde and electric baseboard heating have been shown to increase FeNO, whilst ozone (O3 tends to decrease it. Among children exposed to Environmental Tobacco Smoke (ETS with a genetic polymorphisms in nitric oxide synthase genes (NOS, a higher nicotine exposure was associated with lower FeNO levels. Finally, although more studies are needed in order to better investigate the effect of gene and environment interactions which may affect the interpretation of FeNO values in the management of children with asthma, clinicians are recommended to consider environmental exposures when taking medical histories for asthma and respiratory allergy. Further research is also needed to assess the effects of remedial interventions aimed at reducing/abating environmental exposures in asthmatic/allergic patients.

  17. Reference values for exhaled nitric oxide (reveno study

    Mutti Antonio

    2006-06-01

    Full Text Available Abstract Background Despite the widespread use of fractional exhaled nitric oxide (FENO as a biomarker of airways inflammation, there are no published papers describing normal FENO values in a large group of healthy adults. Objective The aim of this study was to establish adult FENO reference values according to the international guidelines. Methods FENO was measured in 204 healthy, non-smoking adults with normal spirometry values using the on-line single-breath technique, and the results were analysed chemiluminescently. Results The main result of the study was the significant difference in FENO values between men and women, thus indicating that gender-based reference FENO values are necessary. The FENO levels obtained at expiratory flows of 50 ml/s ranged from 2.6 to 28.8 ppb in men, and from 1.6 to 21.5 ppb in women. Conclusion We propose reference FENO values for healthy adult men and women that could be used for clinical and research purposes.

  18. Salivary enzymes and exhaled air affect Streptococcus salivarius growth and physiological state in complemented artificial saliva.

    Roger, P; Harn-Arsa, S; Delettre, J; Béal, C

    2011-12-01

    To better understand the phenomena governing the establishment of the oral bacterium Streptococcus salivarius in the mouth, the effect of some environmental factors has been studied in complemented artificial saliva, under oral pH and temperature conditions. Three salivary enzymes at physiological concentrations were tested: peroxidase, lysozyme and amylase, as well as injection of exhaled air. Injection of air containing 5% CO2 and 16% O2 induced a deleterious effect on S. salivarius K12, mainly by increasing redox potential. Addition of lysozyme slightly affected the physiological state of S. salivarius by altering membrane integrity. In contrast, peroxidase was not detrimental as it made it possible to decrease the redox potential. The addition of amylase reduced the specific growth rate of S. salivarius by formation of a complex with amylase and mucins, but led to high final biomass, as a result of enzymatic degradation of some nutrients. Finally, this work demonstrated that salivary enzymes had a slight impact on S. salivarius behaviour. It can thus be concluded that this bacterium was well adapted to in-mouth conditions, as it was able to resist certain salivary enzymes, even if tolerance to expired air was affected, as a result of an increased redox potential. PMID:21892611

  19. 4$\\pi$ detector for study of Zeno effect using 220Rn -> 216Po alpha->alpha correlated chains

    Nadderd, L; Subotic, K; Polyakov, A N; Lobanov, Y V; Rykhlyuk, A V

    2015-01-01

    First test of the 4pi detector for study of exponential law of radioactive decay and possibility of observation of Zeno effect [1-3], measuring the mean life of 216Po is presented. This detector consists of two surface-barrier n-Si(Au) detectors placed in the close contact ( 4T1/2. Both, the data acquisition system and the vacuum chamber design are presented in brief.

  20. Development of a ZnS:Ag scintillation based portable on-line Thoron (220Rn) monitor

    Thoron is universally present in outdoor air, and can reach higher levels in areas near the beaches with monazite sand and also in plants handling thorium. Several instruments have been developed for measurement of thoron in the environment. Due to the inherent problems with the low sensitivity and humidity dependence of semiconductor based detector, the ZnS:Ag scintillation detector based system has been developed. The detector used for detecting the alpha from Thoron gas and its immediate decay product 216Po is a 153 ml volume flow-through scintillation cell (size 53 mm dia. x 70 mm length) coupled with photomultiplier

  1. Contrasting radon background levels in volcanic settings: Clues from 220Rn activity concentrations measured during long-term deformation experiments

    Scarlato, P.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Tuccimei, P.; Università Roma Tre; Mollo, S.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma1, Roma, Italia; Soligo, M.; Università Roma Tre; Castelluccio, M.; Università Roma Tre

    2013-01-01

    To better understand the mechanisms leading to different radon background levels in volcanic settings, we have performed two long-term deformation experiments of 16 days using a real-time setup that enables us to monitor any variation of radon activity concentration during rock compression. Our measurements demonstrate that, in the case of highly porous volcanic rocks, the emanating power of the substrate changes as a function of the volcanic stress conditions. Constant m...

  2. Nitric oxide production in the exhaled air of patients with pulmonary tuberculosis in relation to HIV co-infection

    Melese Endalkachew

    2008-10-01

    Full Text Available Abstract Background Nitric oxide (NO is essential for host defense in rodents, but the role of NO during tuberculosis (TB in man remains controversial. However, earlier observations that arginine supplementation facilitates anti-TB treatment, supports the hypothesis that NO is important in the host defense against TB. Local production of NO measured in fractional exhaled air (FeNO in TB patients with and without HIV co-infection has not been reported previously. Thus, our aim was to investigate levels of FeNO in relation to clinical symptoms and urinary NO metabolites (uNO. Methods In a cross sectional study, FeNO and uNO were measured and clinical symptoms, chest x-ray, together with serum levels of arginine, tumor necrosis factor alpha (TNF-alpha and interleukin 12 (IL-12 were evaluated in sputum smear positive TB patients (HIV+/TB, n = 36, HIV-/TB, n = 59, their household contacts (n = 17 and blood donors (n = 46 from Gondar University Hospital, Ethiopia. Results The proportion of HIV-/TB patients with an increased FeNO level (> 25 ppb was significantly higher as compared to HIV+/TB patients, but HIV+/TB patients had significantly higher uNO than HIV-/TB patients. HIV+ and HIV-/TB patients both had lower levels of FeNO compared to blood donors and household contacts. The highest levels of both uNO and FeNO were found in household contacts. Less advanced findings on chest x-ray, as well as higher sedimentation rate were observed in HIV+/TB patients as compared to HIV-/TB patients. However, no significant correlation was found between FeNO and uNO, chest x-ray grading, clinical symptoms, TNF-alpha, IL-12, arginine levels or sedimentation rate. Conclusion In both HIV negative and HIV co infected TB patients, low levels of exhaled NO compared to blood donors and household were observed. Future studies are needed to confirm whether low levels of exhaled NO could be a risk factor in acquiring TB and the relative importance of NO in human TB.

  3. EXHALED AND PLASMA NITRITE: a comparative study among healthy, cirrhotic and liver transplant patients

    Viviane S AUGUSTO

    2014-03-01

    Full Text Available Context There is a relative lack of studies about exhaled nitrite (NO2- concentrations in cirrhotic and transplanted patients. Objective Verify possible differences and correlations between the levels of NO2-, measured in plasma and exhaled breath condensate collected from patients with cirrhosis and liver transplant. Method Sixty adult male patients, aged between 27 and 67 years, were subdivided into three groups: a control group comprised of 15 healthy volunteers, a cirrhosis group composed of 15 volunteers, and a transplant group comprised of 30 volunteers. The NO2- concentrations were measured by chemiluminescence. Results 1 The analysis of plasma NO2- held among the three groups showed no statistical significance. 2 The comparison between cirrhotic and control groups, control and transplanted and cirrhotic and transplanted was not statistically significant. 3 The measurements performed on of NO2- exhaled breath condensate among the three groups showed no statistical difference. 4 When comparing the control group samples and cirrhotic, control and transplanted and cirrhotic and transplanted, there was no significant changes in the concentrations of NO2-. Conclusion No correlations were found between plasma and exhaled NO2-, suggesting that the exhaled NO2- is more reflective of local respiratory NO release than the systemic circulation.

  4. Exhaled carbon monoxide in asthmatics: a meta-analysis

    Huang Mao

    2010-04-01

    Full Text Available Abstract Background The non-invasive assessment of airway inflammation is potentially advantageous in asthma management. Exhaled carbon monoxide (eCO measurement is cheap and has been proposed to reflect airway inflammation and oxidative stress but current data are conflicting. The purpose of this meta-analysis is to determine whether eCO is elevated in asthmatics, is regulated by steroid treatment and reflects disease severity and control. Methods A systematic search for English language articles published between 1997 and 2009 was performed using Medline, Embase and Cochrane databases. Observational studies comparing eCO in non-smoking asthmatics and healthy subjects or asthmatics before and after steroid treatment were included. Data were independently extracted by two investigators and analyzed to generate weighted mean differences using either a fixed or random effects meta-analysis depending upon the degree of heterogeneity. Results 18 studies were included in the meta-analysis. The eCO level was significantly higher in asthmatics as compared to healthy subjects and in intermittent asthma as compared to persistent asthma. However, eCO could not distinguish between steroid-treated asthmatics and steroid-free patients nor separate controlled and partly-controlled asthma from uncontrolled asthma in cross-sectional studies. In contrast, eCO was significantly reduced following a course of corticosteroid treatment. Conclusions eCO is elevated in asthmatics but levels only partially reflect disease severity and control. eCO might be a potentially useful non-invasive biomarker of airway inflammation and oxidative stress in nonsmoking asthmatics.

  5. Values in Elderly People for Exhaled Nitric Oxide Study.

    Malerba, Mario; Damiani, Giovanni; Carpagnano, Giovanna E; Olivini, Alessia; Radaeli, Alessandro; Ragnoli, Beatrice; Foschino, Maria Pia; Olivieri, Mario

    2016-06-01

    Ageing population is constantly increasing due to rising life expectancy; consequently, the percentage of the elderly patients with asthma is increasing, as well. Fractional exhaled nitric oxide (FeNO) is a biomarker of lung inflammation, and currently it is widely used in clinical practice for asthma diagnosis and monitoring. Yet, there are no data about normal values of FeNO in patients of more than 65 years of age with normal lung function. The aim of this study was to establish adult FeNO reference values for subjects older than 65 years, according to the international guidelines. FeNO was measured in 303 healthy, nonsmoking adults more than 65 years of age, with normal spirometry values measured using the online single-breath technique. The results were analyzed by chemiluminescent detection. The FeNO levels obtained range from 5.00 to 29.9 ppb, with a mean value of 12.48 ± 2.80 ppb. A significant association of FeNO levels with age (p < 0.05) was observed. There was no difference in FeNO values between men and women unlike what was observed in younger patients. FeNO levels in healthy controls over 65 years of age are influenced by age as in younger adults. However, there is no difference in FeNO values in male and female seniors, in contrast with what was found in younger adults in other studies. These data can be useful for the clinician to interpret the values of FeNO assessed during clinical practice. PMID:26414479

  6. Exhalation analysis as a method of monitoring the incorporation of thorium

    The measurement techniques of whole body counting and analysis of excretion are little suited for the routine monitoring of Thorium body activity. From published data the suitability of exhalation analysis was examined. By using the most sensitiv Thoronmonitors it is possible to determine approximately 1 mBq/l Rn-220 in breath of humans. The relationship between exhaled Rn-220 and the Th-232 activity deposited in liver and spleen of Thorotrast patients was about 2-3 mBq/l Rn-220 per Bq Th-232. Corresponding to this data by exhalation analysis the estimation of 0.5 to 1 Bq Th-232 body burden (equivalent to 30% annual limit for intake of Th-232) is practicable. (orig.)

  7. Effect of Air Stability on the Dispersal of Exhaled Contaminant in Rooms

    Xu, Chunwen; Gong, Guangcai; Nielsen, Peter V.;

    2013-01-01

    Experiments are conducted in a full-scale chamber equipped with whole floor and whole ceiling supply or exhaust to form approximately zero and larger temperature gradients corresponding to unstable and stable air conditions. It can be observed that the air with smoke exhaled from a life-sized the......Experiments are conducted in a full-scale chamber equipped with whole floor and whole ceiling supply or exhaust to form approximately zero and larger temperature gradients corresponding to unstable and stable air conditions. It can be observed that the air with smoke exhaled from a life...... the manikin, indicating that the person who exhales the contaminant may not be polluted by himself as the protective effect of the thermal boundary layer around the body, especially in stable condition with two concentration zones and clean air drawn from the inlets. However, other persons facing the...

  8. Exhaled nitric oxide after high-intensity exercise at 2800 m altitude

    Stang, Julie; Bråten, Veslemøy; Caspersen, Cecilie; Thorsen, Einar; Stensrud, Trine

    2014-01-01

    Background: Nitric oxide (NO) concentration in exhaled gas is a marker of some inflammatory processes in the lung, and endogenous NO plays a role in the physiological responses to exercise and altitude. The aim of this study was to compare changes in exhaled NO concentration 5–60 mins after high-intensity exercise at 2800 m and at 180 m altitude. Methods: Twenty trained healthy volunteers (12 men), aged 19–28 years, were included in this open, crossover study. Subjects performed two exerc...

  9. The Breathing for Life Trial: a randomised controlled trial of fractional exhaled nitric oxide (FENO)-based management of asthma during pregnancy and its impact on perinatal outcomes and infant and childhood respiratory health

    Vanessa E. Murphy; Jensen, Megan E.; Mattes, Joerg; Hensley, Michael J.; Giles, Warwick B; Peek, Michael J.; Bisits, Andrew; Callaway, Leonie K.; McCaffery, Kirsten; Barrett, Helen L.; Colditz, Paul B.; Seeho, Sean K.; Attia, John; Searles, Andrew; Doran, Christopher

    2016-01-01

    Background Asthma exacerbations are common during pregnancy and associated with an increased risk of adverse perinatal outcomes. Adjusting asthma treatment based on airway inflammation rather than symptoms reduces the exacerbation rate by 50 %. The Breathing for Life Trial (BLT) will test whether this approach also improves perinatal outcomes. Methods/design BLT is a multicentre, parallel group, randomised controlled trial of asthma management guided by fractional exhaled nitric oxide (FENO, ...

  10. Children’s Urinary Phthalate Metabolites and Fractional Exhaled Nitric Oxide in an Urban Cohort

    Just, Allan C.; Whyatt, Robin M.; Miller, Rachel L.; Rundle, Andrew G.; Chen, Qixuan; Calafat, Antonia M.; Divjan, Adnan; Rosa, Maria J; Zhang, Hanjie; Perera, Frederica P.; Goldstein, Inge F.; Perzanowski, Matthew S.

    2012-01-01

    Rationale: Phthalates are used widely in consumer products. Exposure to several phthalates has been associated with respiratory symptoms and decreased lung function. Associations between children’s phthalate exposures and fractional exhaled nitric oxide (FeNO), a biomarker of airway inflammation, have not been examined.

  11. Cross Infection in a Hospital Ward and Deposition of Particles Exhaled from a Source Manikin

    Nielsen, Peter V.; Li, Yuguo; Buus, Morten; Winther, Frederik V.; Qian, Hua

    2009-01-01

    The cross infection in a hospital ward is studied. Deposition of particles exhaled from a source manikin is investigated in a full-scale hospital ward ventilated by downward directed ventilation. Deposition on vertical surfaces close to the source shows distribution of particles directed upwards in...

  12. The concentration distributions of some metabolites in the exhaled breath of young adults

    Španěl, Patrik; Dryahina, Kseniya; Smith, D.

    2007-01-01

    Roč. 1, - (2007), 026001. ISSN 1752-7155 R&D Projects: GA ČR GA202/06/0776 Institutional research plan: CEZ:AV0Z40400503 Keywords : metabolites * exhaled breath * concentration distributions Subject RIV: CF - Physical ; Theoretical Chemistry

  13. SIFT-MS Analysis of Nose-Exhaled Breath; Mouth Contamination and the Influence of Exercise

    Smith, D.; Chippendale, T. W. E.; Dryahina, Kseniya; Španěl, Patrik

    2013-01-01

    Roč. 9, č. 2013 (2013), s. 565-575. ISSN 1573-4110 Institutional support: RVO:61388955 Keywords : selected ion flow tube mass spectrometry * breath analysis * nose exhalation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.194, year: 2013

  14. Can volatile compounds in exhaled breath be used to monitor control in diabetes mellitus?

    Smith, D.; Španěl, Patrik; Fryer, A. A.; Hanna, F.; Ferns, G. A. A.

    2011-01-01

    Roč. 5, č. 2 (2011), 022001. ISSN 1752-7155 Institutional research plan: CEZ:AV0Z40400503 Keywords : exhaled breath * diabetes mellitus * SIFT-MS Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.541, year: 2011

  15. Control of exposure to exhaled air from sick occupant with wearable personal exhaust unit

    Bolashikov, Zhecho Dimitrov; Melikov, Arsen Krikor; Barova, Maria I.

    2014-01-01

    Exposure reduction to exhaled air from a sick doctor wearing personal exhaust unit incorporated in headset-microphone was studied. Experiments were performed in a full-scale test room furnished as a double-bed hospital room with overhead ventilation at 3, 6 and 12 ACH. Room air temperature was 22...

  16. Exhaled nitric oxide predicts airway hyper-responsiveness to hypertonic saline in children that wheeze

    de Meer, G; van Amsterdam, JGC; Janssen, NAH; Meijer, E; Brunekreef, B; STEERENBERG, PA

    2005-01-01

    Background: Exhaled nitric oxide (eNO) has shown good validity for the assessment of airway inflammation in asthmatic children. In large-scale epidemiological studies, this method would be preferred above airway challenge tests, because it is a quick and easy applicable tool. Objective: In this stud

  17. Daily home measurements of exhaled nitric oxide in asthmatic children during natural birch pollen exposure

    Vahlkvist, Signe; Sinding, Marianne; Skamstrup, Kirsten;

    2006-01-01

    BACKGROUND: Fractional exhaled nitric oxide (FENO) is a sensitive marker of eosinophilic airway inflammation in asthma. Available methods have restricted measurements to the clinic, giving only a snapshot of the disease, which by nature is highly variable. OBJECTIVES: We sought to investigate the...

  18. Radon and thoron in cave dwellings (Yan'an, China)

    Wiegand, J.; Feige, S.; Xie Quingling; Schreiber, U.; Wieditz, K.; Wittmann, C.; Luo Xiarong

    2000-04-01

    {sup 222}Rn and {sup 220}Rn concentrations were measured in cave dwellings and brick houses in the region of Yan'an (China) during summer 1997. The underground dwellings are built into Quaternary loess, and all investigated houses are founded on it. The median values of indoor {sup 222}Rn and {sup 220}Rn concentrations are 42 (n = 18) and 77Bq m{sup {minus}3} (n = 15) for brick houses and 92 (n = 23) and 215 (n = 17) Bq m{sup {minus}3} for cave dwellings. To classify the dwellings in respect to their cave-character, the fraction of walls having a direct contact to the loess is calculated for each dwelling. While the {sup 222}Rn concentrations are increasing with higher fractions, the {sup 220}Rn concentrations are not correlated with this fraction. On the other hand, due to the short half-life of {sup 220}Rn the distance from the measuring point to the walls is negatively correlated with the {sup 220}Rn concentration, while there is no correlation with the {sup 222}Rn concentration. Therefore, concentric isolines of {sup 220}Rn concentrations showing a strong gradient were detected in cave dwellings. An influence of the ventilation rate is distinct for {sup 222}Rn but weak for {sup 220}Rn. The effective dose rates for {sup 222}Rn and {sup 220}Rn and their progenies are calculated for brick houses (2.7 mSv y{sup {minus}1}), cave dwellings (7.1 mSv y{sup {minus}1}), and for traditional cave dwellings with a bed foundation built with loess (16.7 mSv y{sup {minus}1}). These calculations are based on summer measurements only. It is expected that the true effective dose rates will be significantly higher.

  19. Exhaled breath for drugs of abuse testing - evaluation in criminal justice settings.

    Beck, Olof

    2014-01-01

    Exhaled breath is being developed as a possible specimen for drug testing based on the collection of aerosol particles originating from the lung fluid. The present study was aimed to evaluate the applicability of exhaled breath for drugs of abuse testing in criminal justice settings. Particles in exhaled breath were collected with a new device in parallel with routine urine testing in two Swedish prisons, comprising both genders. Urine screening was performed according to established routines either by dipstick or by immunochemical methods at the Forensic Chemistry Laboratory and confirmations were with mass spectrometry methods. A total of 247 parallel samples were studied. Analysis of exhaled breath samples was done with a sensitive mass spectrometric method and identifications were made according to forensic standards. In addition tested subjects and personnel were asked to fill in a questionnaire concerning their views about drug testing. In 212 cases both the urine and breath testing were negative, and in 22 cases both urine and breath were positive. Out of 6 cases where breath was negative and urine positive 4 concerned THC. Out of 7 cases where, breath was positive and urine negative 6 concerned amphetamine. Detected substances in breath comprised: amphetamine, methamphetamine, THC, methylphenidate, buprenorphine, 6-acetylmorphine, cocaine, benzoylecgonine, diazepam and tramadol. Both the prison inmates and staff members reported breath testing to be preferable due to practical considerations. The results of this study documented that drug testing using exhaled breath provided as many positives as urine testing despite an expected shorter detection window, and that the breath sampling procedure was well accepted and provided practical benefits reported both by the prison inmates and testing personnel. PMID:24438778

  20. Experimental setup and analytical methods for the non-invasive determination of volatile organic compounds, formaldehyde and NOx in exhaled human breath

    Different analytical devices were tested and evaluated for their suitability of breath gas analysis by examining the physiological parameters and chemical substances in the exhaled breath of ten healthy probands during light cycling in dependence of methanol-rich nutrition. The probands exercised under normal breathing conditions on a bicycle ergometer. Breath air was exhaled into a glass cylinder and collected under steady-state conditions. Non-invasively measured parameters were pulse rate, breath frequency, temperature, relative humidity, NOx, total volatile organic compounds (TVOCPAS), carbon dioxide (CO2), formaldehyde, methanol, acetaldehyde, acetone, isoprene and volatile organic compounds (VOCs). Methanol rich food and beverages strongly influenced the concentration of methanol and other organic substances in human breath. On the other hand, nutrition and smoking had no clear effect on the physical conditions of the probands. The proton transfer reaction mass spectrometry (PTR-MS) method was found to be very suitable for the analysis of breath gas but the m/z 31, if assigned to formaldehyde, is sensitive to interferences. The time vs. concentration curves of nitric oxide showed sudden peaks up to 120 ppb in most of the measurements. In one case a strong interference of the NOx signal was observed. The time resolved analysis of exhaled breath gas is of high capability and significance for different applications if reliable analytical techniques are used. Some compounds like nitric oxide (NO), methanol, different VOCs as well as sum parameters like TVOCPAS are especially suitable as markers. Formaldehyde, which is rapidly metabolized in the human body, could be measured reliably as a trace component by the acetylacetone (acac) method but not by PTR-MS.

  1. Experimental setup and analytical methods for the non-invasive determination of volatile organic compounds, formaldehyde and NO{sub x} in exhaled human breath

    Riess, Ulrich; Tegtbur, Uwe [Hannover Medical School, Sports Physiology and Sports Medicine, Carl-Neuberg-Str. 1, 30625 Hannover (Germany); Fauck, Christian; Fuhrmann, Frank; Markewitz, Doreen [Fraunhofer WKI, Department of Material Analysis and Indoor Chemistry, Bienroder Weg 54 E, 38108 Braunschweig (Germany); Salthammer, Tunga, E-mail: tunga.salthammer@wki.fraunhofer.de [Fraunhofer WKI, Department of Material Analysis and Indoor Chemistry, Bienroder Weg 54 E, 38108 Braunschweig (Germany)

    2010-06-11

    Different analytical devices were tested and evaluated for their suitability of breath gas analysis by examining the physiological parameters and chemical substances in the exhaled breath of ten healthy probands during light cycling in dependence of methanol-rich nutrition. The probands exercised under normal breathing conditions on a bicycle ergometer. Breath air was exhaled into a glass cylinder and collected under steady-state conditions. Non-invasively measured parameters were pulse rate, breath frequency, temperature, relative humidity, NO{sub x}, total volatile organic compounds (TVOC{sub PAS}), carbon dioxide (CO{sub 2}), formaldehyde, methanol, acetaldehyde, acetone, isoprene and volatile organic compounds (VOCs). Methanol rich food and beverages strongly influenced the concentration of methanol and other organic substances in human breath. On the other hand, nutrition and smoking had no clear effect on the physical conditions of the probands. The proton transfer reaction mass spectrometry (PTR-MS) method was found to be very suitable for the analysis of breath gas but the m/z 31, if assigned to formaldehyde, is sensitive to interferences. The time vs. concentration curves of nitric oxide showed sudden peaks up to 120 ppb in most of the measurements. In one case a strong interference of the NO{sub x} signal was observed. The time resolved analysis of exhaled breath gas is of high capability and significance for different applications if reliable analytical techniques are used. Some compounds like nitric oxide (NO), methanol, different VOCs as well as sum parameters like TVOC{sub PAS} are especially suitable as markers. Formaldehyde, which is rapidly metabolized in the human body, could be measured reliably as a trace component by the acetylacetone (acac) method but not by PTR-MS.

  2. Study of different factors which can explain the radon exhalation potential of soils; Recherche de differents parametres caracterisant le potentiel d`exhalation en radon des sols

    Demongeot, St

    1997-10-27

    Radon is a natural radioactive gas belonging to the Uranium-238 chain, which is present in the earth crust and produced by the disintegration of radium-226. It is considered as the major source of radiological exposure of man to natural radiation because it can accumulate in indoor atmosphere. So, this health risk must be take into account.The aim of this study is to find some tools in order to identify high radon level area. The first part of this study has consisted in measurement of radon emission from different not sufficient for the estimation of the radon exhalation potential in a given area. In the second part of this work, we have studied the variations of in situ radon concentration as a function of different geological and pedologic parameters of the site. With the results obtained, we have determined the data which have to be considered, and the methodology to be applied for the determination of the radon exhalation of a given area. Furthermore, by the mean of numerical simulations (TRACH Model), it was possible to know the scale of radon flux variation in a given point versus the hydric state of the ground and thus the permeability: these parameters are not easy to measure because of their variabilities with time. The methodology ESPERAS (EStimation du Potential d`Exhalation en Radon des Sols) developed during this work was applied first, at a local scale and then to greater area. The values estimated by this way are in a good agreement with the results of measurements. So, we can determine the areas which are affected by high radon levels. (author)

  3. Radon (222Rn) exhalation rate from the building materials of Tiruchirappalli District (Tamil Nadu State, India)

    Tiruchirappalli district is the central district of Tamil Nadu state having a population of 2,722,290 and area of 4,509 Sq.km and naturally endowed with rich building material resources, like stone, granite, sand, brick, cement etc. which are also supplied to the neighbouring districts. The measurement of radon level in these building materials is important, because radon (222Rn), a radioactive gas, is one of the major causative factors for human lung cancer and hence it is imperative to assess its impact on human health. The samples of building materials were collected from their original sources spread over Tiruchirappalli district. As such 14 sedimentary rock (sand stone) samples, 9 igneous rock (granite) samples, 5 sand samples, 10 brick samples and 11 cement samples were analyzed for activity concentration of 222Rn .The Sealed Can Technique using Solid State Nuclear Track Detector (SSNTD) was employed for the measurement of radon emanation. The activity concentrations of radon in sedimentary rocks analyzed ranged from 13.2 Bq m-3 to 218.0 Bq m-3 with the geometric mean activity of 46.3 Bq m-3

  4. Variability of exhaled breath condensate (EBC) volume and pH using a feedback regulated breathing pattern

    Exhaled breath condensate (EBC) is a valuable biological medium for non-invasively measuring biomarkers with the potential to reflect organ systems responses to environmental and dietary exposures and disease processes. Collection of EBC has typically been with spontaneous breat...

  5. Investigation of the Radon exhalation potential in the PACA region. Phase II: case of high potential exhalation areas in Medium Champsaur (05) and South Esterel (83). Final report

    After having recalled the results of the first phase of the study and the objectives of the second phase, the authors present the methodology: uranium and thorium analysis on rock, radon-222 activity measurement in soil gases, and gamma radiation measurement. They discuss the influence of rock uranium content on radon exhalation (natural contextual and physical phenomena governing radon transport, radon properties, uranium geochemistry). They report the results obtained in the two considered areas (meteorological conditions, radon 222 content in soils, uranium and thorium contents in geological formations, influence of geological formation type and distribution on radon activity)

  6. Development of a novel graphene/polyaniline electrodeposited coating for on-line in-tube solid phase microextraction of aldehydes in human exhaled breath condensate.

    Li, Yu; Xu, Hui

    2015-05-22

    In this work, we introduced a novel graphene/polyaniline (G/PANI) electrodeposited coating for on-line in-tube solid phase microextraction (IT-SPME) for the first time. The G/PANI coating was prepared on the internal surface of stainless steel tube by a facile in-situ electrodeposition method. The morphology and formation of the composite coating were confirmed by scanning electronic microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Some important experimental parameters that could affect the extraction and separation such as the coating thickness, internal diameter of tube, sampling flow rate as well as sample volume were optimized. The extraction performance of the IT-SPME coating was evaluated systematically. The coating exhibited enhanced mechanical stability, long lifespan, large specific surface area and good biocompatibility compared with polyaniline coating. The on-line IT-SPME method showed higher enrichment efficiency, faster analysis speed and higher automation level than off-line manual mode. Six aldehydes were determined simultaneously with low limits of detection of 0.02-0.04nmolL(-1) and good linearity (R(2)≥0.9920). The method has been applied successfully for the determination of aldehydes in human exhaled breath condensates with good recovery (70-120%) and satisfied reproducibility (relative standard deviation: 1.1-11.9%). This on-line IT-SPME method provides a promising approach for the determination of trace aldehydes with approving sensitivity in human exhaled breath condensates. PMID:25863926

  7. Measurement of exhaled nitric oxide in beef cattle using tunable diode laser absorption spectroscopy

    Roller, C. B.; Holland, B. P.; McMillen, G.; Step, D. L.; Krehbiel, C. R.; Namjou, K.; McCann, P. J.

    2007-03-01

    Measurement of nitric oxide (NO) in the expired breath of crossbred calves received at a research facility was performed using tunable diode laser absorption spectroscopy. Exhaled NO (eNO) concentrations were measured using NO absorption lines at 1912.07 cm-1 and employing background subtraction. The lower detection limit and measurement precision were determined to be ˜330 parts in 1012 per unit volume. A custom breath collection system was designed to collect lower airway breath of spontaneously breathing calves while in a restraint chute. Breath was collected and analyzed from calves upon arrival and periodically during a 42 day receiving period. There was a statistically significant relationship between eNO, severity of bovine respiratory disease (BRD) in terms of number of times treated, and average daily weight gain over the first 15 days postarrival. In addition, breathing patterns and exhaled CO2 showed a statistically significant relationship with BRD morbidity.

  8. Endothelin-1 in exhaled breath condensate of allergic asthma patients with exercise-induced bronchoconstriction

    Tomasiak Maria M; Skiepko Roman; Zietkowski Ziemowit; Bodzenta-Lukaszyk Anna

    2007-01-01

    Abstract Background Exercise-induced bronchoconstriction (EIB) is a highly prevalent condition, whose pathophysiology is not well understood. Endothelins are proinflammatory, profibrotic, broncho- and vasoconstrictive peptides which play an important role in the development of airway inflammation and remodeling in asthma. The aim of the study was to evaluate the changes in endothelin-1 levels in exhaled breath condensate following intensive exercise in asthmatic patients. Methods The study wa...

  9. Exhaled nitric oxide is related to atopy, but not asthma in adolescents with bronchiolitis in infancy

    Mikalsen, Ingvild Bruun; Halvorsen, Thomas; Øymar, Knut

    2013-01-01

    Background: The fraction of exhaled nitric oxide (FeNO) has been suggested as a non-invasive marker of eosinophilic inflammation in asthma, but lately rather as a biomarker of atopy than of asthma itself. Asthma after bronchiolitis is common up to early adolescence, but the inflammation and pathophysiology may differ from other phenotypes of childhood asthma. We aimed to assess if FeNO was different in children with former hospitalization for bronchiolitis and a control group, and...

  10. Assessment of Fractionated Exhaled Nitric Oxide as a Biomarker for the Treatment of Eosinophilic Esophagitis

    Leung, John; Nguyen-Traxler, Ann; Lee, Erika M.; Yip, Jason S.; Weinstock, Joel V.; Chan, Walter Wai-Yip; Ngo, Peter; Weinstein, Barbara J.; Bonis, Peter A.

    2012-01-01

    Diagnosis of eosinophilic esophagitis (EoE) and determination of response to therapy is based on histological assessment of the esophagus, which requires upper endoscopy. In children, in whom a dietary approach is commonly used, multiple endoscopies are needed, because foods are eliminated and then gradually reintroduced. Ideally, noninvasive methods could supplement or replace upper endoscopy to facilitate management. Fractionated exhaled nitric oxide (FeNO) has been proposed as a useful mea...

  11. Associations between nitric oxide synthase genes and exhaled NO-related phenotypes according to asthma status.

    Emmanuelle Bouzigon

    Full Text Available BACKGROUND: The nitric oxide (NO pathway is involved in asthma, and eosinophils participate in the regulation of the NO pool in pulmonary tissues. We investigated associations between single nucleotide polymorphisms (SNPs of NO synthase genes (NOS and biological NO-related phenotypes measured in two compartments (exhaled breath condensate and plasma and blood eosinophil counts. METHODOLOGY: SNPs (N = 121 belonging to NOS1, NOS2 and NOS3 genes were genotyped in 1277 adults from the French Epidemiological study on the Genetics and Environment of Asthma (EGEA. Association analyses were conducted on four quantitative phenotypes: the exhaled fraction of NO (Fe(NO, plasma and exhaled breath condensate (EBC nitrite-nitrate levels (NO2-NO3 and blood eosinophils in asthmatics and non-asthmatics separately. Genetic heterogeneity of these phenotypes between asthmatics and non-asthmatics was also investigated. PRINCIPAL FINDINGS: In non-asthmatics, after correction for multiple comparisons, we found significant associations of Fe(NO levels with three SNPs in NOS3 and NOS2 (P ≤ 0.002, and of EBC NO2-NO3 level with NOS2 (P = 0.002. In asthmatics, a single significant association was detected between Fe(NO levels and one SNP in NOS3 (P = 0.004. Moreover, there was significant heterogeneity of NOS3 SNP effect on Fe(NO between asthmatics and non-asthmatics (P = 0.0002 to 0.005. No significant association was found between any SNP and NO2-NO3 plasma levels or blood eosinophil counts. CONCLUSIONS: Variants in NO synthase genes influence Fe(NO and EBC NO2-NO3 levels in adults. These genetic determinants differ according to asthma status. Significant associations were only detected for exhaled phenotypes, highlighting the critical relevance to have access to specific phenotypes measured in relevant biological fluid.

  12. Factors attributable to the level of exhaled nitric oxide in asthmatic children

    Banovcin P

    2009-12-01

    Full Text Available Abstract Background Asthma is a heterogeneous disease with variable symptoms especially in children. Exhaled nitric oxide (FeNO has proved to be a marker of inflammation in the airways and has become a substantial part of clinical management of asthmatic children due to its potential to predict possible exacerbation and adjust the dose of inhalant corticosteroids. Objectives We analyzed potential factors that contribute to the variability of nitric oxide in various clinical and laboratory conditions. Materials and methods Study population consisted of 222 asthmatic children and 27 healthy control subjects. All children underwent a panel of tests: fractioned exhaled nitric oxide, exhaled carbon monoxide, asthma control test scoring, blood sampling, skin prick tests, and basic spirometry. Results FeNO and other investigated parameters widely changed according to clinical or laboratory characteristics of the tested children. Asthmatics showed increased levels of FeNO, exhaled carbon monoxide, total serum IgE, and higher eosinophilia. Boys had higher FeNO levels than girls. We found a significant positive correlation between FeNO levels and the percentage of blood eosinophils, %predicted of forced vital capacity, total serum IgE levels, and increasing age. Conclusions Various phenotypes of children's asthma are characterized by specific pattern of the results of clinical and laboratory tests. FeNO correlates with total serum IgE, blood eosinophilia, age, and some spirometric parameters with different strength. Therefore, the coexistence of atopy, concomitant allergic rhinitis/rhinoconjunctivitis, and some other parameters should be considered in critical evaluation of FeNO in the management of asthmatic children.

  13. Trichloroethene levels in human blood and exhaled breath from controlled inhalation exposure.

    Pleil, J D; Fisher, J W; Lindstrom, A B

    1998-01-01

    The organic constituents of exhaled human breath are representative of bloodborne concentrations through gas exchange in the blood/breath interface in the lungs. The presence of specific compounds can be an indicator of recent exposure or represent a biological response of the subject. For volatile organic compounds, sampling and analysis of breath is preferred to direct measurement from blood samples because breath collection is noninvasive, potentially infectious waste is avoided, the sampl...

  14. Exhaled nitric oxide and airway hyperresponsiveness in workers: a preliminary study in lifeguards

    Massin Nicole; Bohadana Abraham; Demange Valérie; Wild Pascal

    2009-01-01

    Abstract Background Airway inflammation and airway hyperresponsiveness (AHR) are two characteristic features of asthma. Fractional exhaled nitric oxide (FENO) has shown good correlation with AHR in asthmatics. Less information is available about FENO as a marker of inflammation from work exposures. We thus examined the relation between FENO and AHR in lifeguards undergoing exposure to chloramines in indoor pools. Methods 39 lifeguards at six indoor pools were given a respiratory health questi...

  15. Increased exhaled nitric oxide in patients with stable chronic obstructive pulmonary disease

    Corradi, M.; Majori, M.; Cacciani, G. C.; Consigli, G. F.; Munari, E.; A. Pesci

    1999-01-01

    BACKGROUND—Nitric oxide (NO) plays an important role as an inflammatory mediator in the airways. Since chronic obstructive pulmonary disease (COPD) is characterised by airway inflammation, a study was undertaken to determine NO levels in the exhaled air of patients with COPD.
METHODS—Two groups of patients with clinically stable COPD were studied, 10 current smokers and 10 ex-smokers. Two control groups of healthy subjects consisting of 10 current smokers and 20 non-smoke...

  16. Aspergillus spp. colonization in exhaled breath condensate of lung cancer patients from Puglia Region of Italy

    Carpagnano, Giovanna E; Lacedonia, Donato; Palladino, Grazia Pia; Logrieco, Giuseppe; Crisetti, Elisabetta; Susca, Antonia; Logrieco, Antonio; Foschino-Barbaro, Maria P

    2014-01-01

    Background Airways of lung cancer patients are often colonized by fungi. Some of these colonizing fungi, under particular conditions, produce cancerogenic mycotoxins. Given the recent interest in the infective origin of lung cancer, with this preliminary study we aim to give our small contribution to this field of research by analysing the fungal microbiome of the exhaled breath condensate of lung cancer patients from Puglia, a region of Italy. Methods We enrolled 43 lung cancer patients and ...

  17. Electronic Nose and Exhaled Breath NMR-based Metabolomics Applications in Airways Disease.

    Santini, Giuseppe; Mores, Nadia; Penas, Andreu; Capuano, Rosamaria; Mondino, Chiara; Trové, Andrea; Macagno, Francesco; Zini, Gina; Cattani, Paola; Martinelli, Eugenio; Motta, Andrea; Macis, Giuseppe; Ciabattoni, Giovanni; Montuschi, Paolo

    2016-01-01

    Breathomics, the multidimensional molecular analysis of exhaled breath, includes analysis of exhaled breath with gas-chromatography/mass spectrometry (GC/MS) and electronic noses (e-noses), and metabolomics of exhaled breath condensate (EBC), a non-invasive technique which provides information on the composition of airway lining fluid, generally by high-resolution nuclear magnetic resonance (NMR) spectroscopy or MS methods. Metabolomics is the identification and quantification of small molecular weight metabolites in a biofluid. Specific profiles of volatile compounds in exhaled breath and metabolites in EBC (breathprints) are potentially useful surrogate markers of inflammatory respiratory diseases. Electronic noses (e-noses) are artificial sensor systems, usually consisting of chemical cross-reactive sensor arrays for characterization of patterns of breath volatile compounds, and algorithms for breathprints classification. E-noses are handheld, portable, and provide real-time data. E-nose breathprints can reflect respiratory inflammation. E-noses and NMR-based metabolomics of EBC can distinguish patients with respiratory diseases such as asthma, COPD, and lung cancer, or diseases with a clinically relevant respiratory component including cystic fibrosis and primary ciliary dyskinesia, and healthy individuals. Breathomics has also been reported to identify patients affected by different types of respiratory diseases. Patterns of breath volatile compounds detected by e-nose and EBC metabolic profiles have been associated with asthma phenotypes. In combination with other -omics platforms, breathomics might provide a molecular approach to respiratory disease phenotyping and a molecular basis to tailored pharmacotherapeutic strategies. Breathomics might also contribute to identify new surrogate markers of respiratory inflammation, thus, facilitating drug discovery. Validation in newly recruited, prospective independent cohorts is essential for development of e

  18. Effect of pulmonary rehabilitation on exhaled nitric oxide in patients with chronic obstructive pulmonary disease

    E. Clini; Bianchi, L.; Foglio, K.; R. Porta; Vitacca, M.; Ambrosino, N

    2001-01-01

    BACKGROUND—In patients with mild to moderate chronic obstructive pulmonary disease (COPD) the exercise induced increase in exhaled nitric oxide (eNO) parallels that observed in normal untrained subjects. There is no information on the effects of the level of exercise tolerance on eNO in these patients. The aim of this study was to evaluate the effect of a pulmonary rehabilitation programme including exercise training on eNO in patients with COPD.
METHODS—In 14 consecutive...

  19. Characterization of exhaled breath particles collected by an electret filter technique.

    Tinglev, Åsa Danielsson; Ullah, Shahid; Ljungkvist, Göran; Viklund, Emilia; Olin, Anna-Carin; Beck, Olof

    2016-06-01

    Aerosol particles that are present in exhaled breath carry nonvolatile components and have gained interest as a specimen for potential biomarkers. Nonvolatile compounds detected in exhaled breath include both endogenous and exogenous compounds. The aim of this study was to study particles collected with a new, simple and convenient filter technique. Samples of breath were collected from healthy volunteers from approximately 30 l of exhaled air. Particles were counted with an optical particle counter and two phosphatidylcholines were measured by liquid chromatography-tandem mass spectrometry. In addition, phosphatidylcholines and methadone was analysed in breath from patients in treatment with methadone and oral fluid was collected with the Quantisal device. The results demonstrated that the majority of particles are  particle contributes most to the total mass. The phosphatidylcholine PC(16 : 0/16 : 0) dominated over PC(16 : 0/18 : 1) and represented a major constituent of the particles. The concentration of the PC(16 : 0/16 : 0) homolog was significantly correlated (p  particles is a promising strategy for measurement of nonvolatiles in breath. PMID:26987381

  20. Stable isotope and high precision concentration measurements confirm that all humans produce and exhale methane.

    Keppler, Frank; Schiller, Amanda; Ehehalt, Robert; Greule, Markus; Hartmann, Jan; Polag, Daniela

    2016-03-01

    Mammalian formation of methane (methanogenesis) is widely considered to occur exclusively by anaerobic microbial activity in the gastrointestinal tract. Approximately one third of humans, depending on colonization of the gut by methanogenic archaea, are considered methane producers based on the classification terminology of high and low emitters. In this study laser absorption spectroscopy was used to precisely measure concentrations and stable carbon isotope signatures of exhaled methane in breath samples from 112 volunteers with an age range from 1 to 80 years. Here we provide analytical evidence that volunteers exhaled methane levels were significantly above background (inhaled) air. Furthermore, stable carbon isotope values of the exhaled methane unambiguously confirmed that this gas was produced by all of the human subjects studied. Based on the emission and stable carbon isotope patterns of various age groups we hypothesize that next to microbial sources in the gastrointestinal tracts there might be other, as yet unidentified, processes involved in methane formation supporting the idea that humans might also produce methane endogenously in cells. Finally we suggest that stable isotope measurements of volatile organic compounds such as methane might become a useful tool in future medical research diagnostic programs. PMID:26824393

  1. Dose-dependent onset and cessation of action of inhaled budesonide on exhaled nitric oxide and symptoms in mild asthma

    Kharitonov, S; Donnelly, L; Montuschi, P; Corradi, M; Collins, J; Barnes, P

    2002-01-01

    Background: Dose dependent anti-inflammatory effects of inhaled corticosteroids in asthma are difficult to demonstrate in clinical practice. The anti-inflammatory effect of low dose inhaled budesonide on non-invasive exhaled markers of inflammation and oxidative stress were assessed in patients with mild asthma. Methods: 28 patients entered a double blind, placebo controlled, parallel group study and were randomly given either 100 or 400 µg budesonide or placebo once daily, inhaled from a dry powder inhaler (Turbohaler), for 3 weeks followed by 1 week without treatment. Exhaled nitric oxide (NO), exhaled carbon monoxide (CO), nitrite/nitrate, S-nitrosothiols, and 8-isoprostanes in exhaled breath condensate were measured four times during weeks 1 and 4, and once a week during weeks 2 and 3. Results: A dose-dependent speed of onset and cessation of action of budesonide was seen on exhaled NO and asthma symptoms. Treatment with 400 µg/day reduced exhaled NO faster (–2.06 (0.37) ppb/day) than 100 µg/day (–0.51 (0.35) ppb/day; p<0.01). The mean difference between the effect of 100 and 400 µg budesonide was –1.55 ppb/day (95% CI –2.50 to –0.60). Pretreatment NO levels were positively related to the subsequent speed of reduction during the first 3–5 days of treatment. Faster recovery of exhaled NO was seen after stopping treatment with budesonide 400 µg/day (1.89 (1.43) ppb/day) than 100 µg/day (0.49 (0.34) ppb/day, p<0.01). The mean difference between the effect of 100 and 400 µg budesonide was 1.40 ppb/day (95% CI –0.49 to 2.31). Symptom improvement was dose-dependent, although symptoms returned faster in patients treated with 400 µg/day. A significant reduction in exhaled nitrite/nitrate and S-nitrosothiols after budesonide treatment was not dose-dependent. There were no significant changes in exhaled CO or 8-isoprostanes in breath condensate. Conclusion: Measurement of exhaled NO levels can indicate a dose-dependent onset and cessation of anti

  2. Surfactant Protein A in Exhaled Endogenous Particles Is Decreased in Chronic Obstructive Pulmonary Disease (COPD Patients: A Pilot Study.

    Mona Lärstad

    Full Text Available Exhaled, endogenous particles are formed from the epithelial lining fluid in small airways, where surfactant protein A (SP-A plays an important role in pulmonary host defense. Based on the knowledge that chronic obstructive pulmonary disease (COPD starts in the small airway epithelium, we hypothesized that chronic inflammation modulates peripheral exhaled particle SP-A and albumin levels. The main objective of this explorative study was to compare the SP-A and albumin contents in exhaled particles from patients with COPD and healthy subjects and to determine exhaled particle number concentrations.Patients with stable COPD ranging from moderate to very severe (n = 13, and healthy non-smoking subjects (n = 12 were studied. Subjects performed repeated breath maneuvers allowing for airway closure and re-opening, and exhaled particles were optically counted and collected on a membrane using the novel PExA® instrument setup. Immunoassays were used to quantify SP-A and albumin.COPD patients exhibited significantly lower SP-A mass content of the exhaled particles (2.7 vs. 3.9 weight percent, p = 0.036 and lower particle number concentration (p<0.0001 than healthy subjects. Albumin mass contents were similar for both groups.Decreased levels of SP-A may lead to impaired host defense functions of surfactant in the airways, contributing to increased susceptibility to COPD exacerbations. SP-A in exhaled particles from small airways may represent a promising non-invasive biomarker of disease in COPD patients.

  3. Separately measuring radon and thoron concentrations exhaled from soil using AlphaGUARD and liquid scintillation counter methods

    It was shown that radon and thoron concentrations exhaled from soil were separately measured using the AlphaGUARD and liquid scintillation counter (LSC) methods. The thoron concentrations from the RAD 7 were used to create the conversion equation to calculate thoron levels with the AlphaGUARD. However, the conversion factor was found to depend on the air flow rate. When air containing thoron of ∼60 kBq m-3 was fed to the scintillation cocktail, thoron and thoron progeny could not be measured with the LSC method. The radon concentration of about 10 kBq m-3 was measured with three methods, first with the LSC method and then with two AlphaGUARDs (one in the diffusion mode and the other in the flow mode (0.5 l min-1)). There were no significant differences between these results. Finally, it was shown that the radon and thoron concentrations in air could be measured with the AlphaGUARD and LSC methods. (authors)

  4. Laboratory research on tailings stabilization methods and their effectiveness in radiation containment. [Uranium, reduction of radon exhalation

    Macbeth, P.J.; Jensen, C.M.; Rogers, V.C.; Overmyer, R.F.

    1978-04-01

    This report describes a study of various methods, techniques, and materials for stabilizing uranium mill tailings to reduce radon exhalation. Radon emanation from tailings particles, radon exhalation from tailings, and methods that could be used to reduce radon exhalation from tailings piles are discussed. Surface radon flux and soil gas concentrations were measured in experiment chambers or columns consisting of uranium tailings and various types and thicknesses of cover materials. The applicability of diffusion theory was examined and effective diffusion coefficients were determined for clay, soil, and sand. The variation of radon flux with atmospheric effects and moisture also was investigated. The effectiveness of several types of chemical stabilizers for both volumetric and surface application in reducing radon exhalation is reported. Some volumetric stabilizers reduced radon flux by 90 percent or more. Radon flux was determined through the use of charcoal gas mask canisters, and flux accumulation chambers sampled by Lucas cells. Both of these techniques are described. Soil gas concentration was sampled with Lucas cells and counted with a sodium iodide scintillation spectrometer system. Emanating power of uranium tailings was measured for several particle sizes and found to be relatively constant at about 20 percent. Two types of grasses were found that would grow in tailings if sufficient water and fertilizer were provided. The effect of vegetation on radon exhalation was not determined.

  5. Fiber content of diet affects exhaled breath volatiles in fasting and postprandial state in a pilot crossover study.

    Raninen, Kaisa J; Lappi, Jenni E; Mukkala, Maria L; Tuomainen, Tomi-Pekka; Mykkänen, Hannu M; Poutanen, Kaisa S; Raatikainen, Olavi J

    2016-06-01

    Our pilot study examined the potential of exhaled breath analysis in studying the metabolic effects of dietary fiber (DF). We hypothesized that a high-fiber diet (HFD) containing whole grain rye changes volatile organic compound (VOC) levels in exhaled breath and that consuming a single meal affects these levels. Seven healthy men followed a week-long low-fiber diet (17 g/d) and HFD (44 g/d) in a randomized crossover design. A test meal containing 50 g of the available carbohydrates from wheat bread was served as breakfast after each week. Alveolar exhaled breath samples were analyzed at fasting state and 30, 60, and 120 minutes after this meal parallel to plasma glucose, insulin, and serum lipids. We used solid-phase microextraction and gas chromatography-mass spectrometry for detecting changes in 15 VOCs. These VOCs were acetone, ethanol, 1-propanol, 2-propanol, 1-butanol, acetic acid, propionic acid, butyric acid, valeric acid, isovaleric acid, 2-methylbutyric acid, hexanoic acid, acetoin, diacetyl, and phenol. Exhaled breath 2-methylbutyric acid in the fasting state and 1-propanol at 120 minutes decreased (P = .091 for both) after an HFD. Ingestion of the test meal increased ethanol, 1-propanol, acetoin, propionic acid, and butyric acid levels while reducing acetone, 1-butanol, diacetyl, and phenol levels. Both DF diet content and having a single meal affected breathVOCs. Exploring exhaled breath further could help to develop tools for monitoring the metabolic effects of DF. PMID:27188907

  6. Radon exhalation of cementitious materials made with coal fly ash: Part 1 - scientific background and testing of the cement and fly ash emanation

    Increased interest in measuring radionuclides and radon concentrations in fly ash, cement and other components of building products is due to the concern of health hazards of naturally occurring radioactive materials (NORM). The current work focuses on studying the influence of fly ash (FA) on radon-exhalation rate (radon flux) from cementitious materials. The tests were carried out on cement paste specimens with different FA contents. The first part of the paper presents the scientific background and describes the experiments, which we designed for testing the radon emanation of the raw materials used in the preparation of the cement-FA pastes. It is found that despite the higher 226Ra content in FA (more than 3 times, compared with Portland cement) the radon emanation is significantly lower in FA (7.65% for cement vs. 0.52% only for FA)

  7. Development of method for quantification of {sup 222}Rn exhalation ratio at radioactive waste dam and soil study as mitigator material; Desenvolvimento de metodo para quantificacao de taxa de exalacao de {sup 222}Rn em bacia de rejeitos radioativos e estudo de solo como material mitigador

    Macacini, Jose Flavio

    2008-07-01

    The Brazilian uranium mining company (INB) processed 2.32 10{sup 6} tons of uranium ore in its ore treatment unit (UTM - Caldas), located in the Pocos de Caldas plateau. During 16 years of operation, this unit discarded 2.39 10{sup 6} tons of solid waste in a tailing dam, with an average activity concentration of {sup 226}Ra of 7311 {+-} 184 Bq kg{sup -1}. Most of the atoms of {sup 222}Rn generated from the radioactive waste of the tailing dam remain bounded to the mineral structure. However, a fraction of these atoms can be released from the mineral structure and then emanate. Reaching the porous space of the waste piles, the {sup 222}Rn moves towards the interface waste-atmosphere, exhaling into the atmosphere. The featuring properties of the {sup 222}Rn transport and the biological damage caused by its progeny transform this small chain of radionuclides into a scourge of nature. Because of that, the dry area of the tailing dam was the scope of this work. A methodology was developed for quantifying the exhalation rate of {sup 222}Rn. Moreover, the soil from its surroundings was experimentally evaluated as a cover material to reduce the exhalation of {sup 222}Rn. A collector of {sup 222}Rn was developed, being denominated 607. This collector was proved to be exact and precise after laboratory tests, when a standard for {sup 222}Rn exhalation was prepared with caldasite, an uranium ore with high concentration of {sup 226}Ra (26611 {+-} 581 Bq kg{sup -1}), crushed to the granulometric interval from 1.168 mm to 0.589 mm. The results of {sup 222}Rn exhalation rate using the collector 607 were not influenced by the adsorption of water steam, considering sampling periods lower than 5 days and mass of water steam lower than 7 g. Sampling for measuring {sup 222}Rn exhalation rates in the dry area of the tailing dam was carried out using the collector 607, following the experimental design established by the United States Environmental Protection Agency (US EPA). The

  8. Development of a predictive methodology for identifying high radon exhalation potential areas

    Radon 222 is a radioactive natural gas originating from the decay of radium 226 which itself originates from the decay of uranium 23 8 naturally present in rocks and soil. Inhalation of radon gas and its decay products is a potential health risk for man. Radon can accumulate in confined environments such as buildings, and is responsible for one third of the total radiological exposure of the general public to radiation. The problem of how to manage this risk then arises. The main difficulty encountered is due to the large variability of exposure to radon across the country. A prediction needs to be made of areas with the highest density of buildings with high radon levels. Exposure to radon varies depending on the degree of confinement of the habitat, the lifestyle of the occupants and particularly emission of radon from the surface of the soil on which the building is built. The purpose of this thesis is to elaborate a methodology for determining areas presenting a high potential for radon exhalation at the surface of the soil. The methodology adopted is based on quantification of radon exhalation at the surface, starting from a precise characterization of the main local geological and pedological parameters that control the radon source and its transport to the ground/atmosphere interface. The methodology proposed is innovative in that it combines a cartographic analysis, parameters integrated into a Geographic Information system, and a simplified model for vertical transport of radon by diffusion through pores in the soil. This methodology has been validated on two typical areas, in different geological contexts, and gives forecasts that generally agree with field observations. This makes it possible to identify areas with a high exhalation potential within a range of a few square kilometers. (author)

  9. Study of different factors which can explain the radon exhalation potential of soils

    Radon is a natural radioactive gas belonging to the Uranium-238 chain, which is present in the earth crust and produced by the disintegration of radium-226. It is considered as the major source of radiological exposure of man to natural radiation because it can accumulate in indoor atmosphere. So, this health risk must be take into account.The aim of this study is to find some tools in order to identify high radon level area. The first part of this study has consisted in measurement of radon emission from different not sufficient for the estimation of the radon exhalation potential in a given area. In the second part of this work, we have studied the variations of in situ radon concentration as a function of different geological and pedologic parameters of the site. With the results obtained, we have determined the data which have to be considered, and the methodology to be applied for the determination of the radon exhalation of a given area. Furthermore, by the mean of numerical simulations (TRACH Model), it was possible to know the scale of radon flux variation in a given point versus the hydric state of the ground and thus the permeability: these parameters are not easy to measure because of their variabilities with time. The methodology ESPERAS (EStimation du Potential d'Exhalation en Radon des Sols) developed during this work was applied first, at a local scale and then to greater area. The values estimated by this way are in a good agreement with the results of measurements. So, we can determine the areas which are affected by high radon levels. (author)

  10. Lactobacillus reuteri modulates cytokines production in exhaled breath condensate of children with atopic dermatitis.

    Miniello, Vito Leonardo; Brunetti, Luigia; Tesse, Riccardina; Natile, Miria; Armenio, Lucio; Francavilla, Ruggiero

    2010-05-01

    We measured the concentration of interferon-gamma and interleukin-4 in the exhaled breath condensate of children with atopic and nonallergic dermatitis receiving a probiotic supplementation (Lactobacillus reuteri ATCC 55730) or placebo for 8 weeks. We demonstrated that the levels of these cytokines increased and decreased respectively only in atopic subjects receiving active treatment. Our data suggest that the oral administration of a specific probiotic strain in patients with atopic dermatitis can modulate in vivo the cytokine pattern at a different site from intestine. PMID:20639717

  11. The human volatilome: volatile organic compounds (VOCs) in exhaled breath, skin emanations, urine, feces and saliva.

    Amann, Anton; Costello, Ben de Lacy; Miekisch, Wolfram; Schubert, Jochen; Buszewski, Bogusław; Pleil, Joachim; Ratcliffe, Norman; Risby, Terence

    2014-09-01

    Breath analysis is a young field of research with its roots in antiquity. Antoine Lavoisier discovered carbon dioxide in exhaled breath during the period 1777-1783, Wilhelm (Vilém) Petters discovered acetone in breath in 1857 and Johannes Müller reported the first quantitative measurements of acetone in 1898. A recent review reported 1765 volatile compounds appearing in exhaled breath, skin emanations, urine, saliva, human breast milk, blood and feces. For a large number of compounds, real-time analysis of exhaled breath or skin emanations has been performed, e.g., during exertion of effort on a stationary bicycle or during sleep. Volatile compounds in exhaled breath, which record historical exposure, are called the 'exposome'. Changes in biogenic volatile organic compound concentrations can be used to mirror metabolic or (patho)physiological processes in the whole body or blood concentrations of drugs (e.g. propofol) in clinical settings-even during artificial ventilation or during surgery. Also compounds released by bacterial strains like Pseudomonas aeruginosa or Streptococcus pneumonia could be very interesting. Methyl methacrylate (CAS 80-62-6), for example, was observed in the headspace of Streptococcus pneumonia in concentrations up to 1420 ppb. Fecal volatiles have been implicated in differentiating certain infectious bowel diseases such as Clostridium difficile, Campylobacter, Salmonella and Cholera. They have also been used to differentiate other non-infectious conditions such as irritable bowel syndrome and inflammatory bowel disease. In addition, alterations in urine volatiles have been used to detect urinary tract infections, bladder, prostate and other cancers. Peroxidation of lipids and other biomolecules by reactive oxygen species produce volatile compounds like ethane and 1-pentane. Noninvasive detection and therapeutic monitoring of oxidative stress would be highly desirable in autoimmunological, neurological, inflammatory diseases and cancer

  12. Normal values of exhaled carbon monoxide in healthy subjects: comparison between two methods of assessment

    Moscato, Umberto; Poscia, Andrea; Gargaruti, Riccardo; Capelli, Giovanni; Cavaliere, Franco

    2014-01-01

    Background In a previous study, exhaled carbon monoxide (eCO) has been assessed in healthy non-smokers with a photo acoustic spectrometer Brüel&Kjær 1312. Unexpectedly, values were higher than those reported in literature, which were mostly obtained with electrochemical analysers. This study was aimed to compare eCO values obtained with Brüel&Kjær 1312 and PiCO + Smokerlyzer, a largely utilized electrochemical analyser. Methods Thirty-four healthy subjects, 15 non-smokers and 19 smokers, unde...

  13. Investigation of the Radon exhalation potential in the PACA region. Phase II: case of high potential exhalation areas in Medium Champsaur (05) and South Esterel (83). Final report; Etude du potentiel d'exhalation du Radon en Region PACA. Phase 2: cas des zones a exhalation potentielle elevee en Moyen Champsaur (05) et au Sud -Esterel (83). Rapport final

    NONE

    2009-07-01

    After having recalled the results of the first phase of the study and the objectives of the second phase, the authors present the methodology: uranium and thorium analysis on rock, radon-222 activity measurement in soil gases, and gamma radiation measurement. They discuss the influence of rock uranium content on radon exhalation (natural contextual and physical phenomena governing radon transport, radon properties, uranium geochemistry). They report the results obtained in the two considered areas (meteorological conditions, radon 222 content in soils, uranium and thorium contents in geological formations, influence of geological formation type and distribution on radon activity)

  14. The application of additional respiration resistance on exhale for increasing special endurance of highly qualified rowers

    Grechuha S.V.

    2012-04-01

    Full Text Available The influence of experimental training programs with the application of additional respiration resistance of exhale on the efficiency of covering competitive distances in rowing and canoeing was considered. Thirteen highly qualified rowers participated in the research. The investigation was held in preparatory period and before contest mesocycle. The improvement of the uniform course of the boat was found in the preparatory period. The period of super-restoration of functional state of respiration muscles was found at the end of the effect. The improvement of the results was determined at the distances of 500 and 1000 m in the competitive period

  15. Lung function and fractional exhaled nitric oxide among petroleum refinery workers

    Meo, Sultan Ayoub; Alrashed, Abdulrahman Hamad; Almana, Abdulrahman Abdulaziz; Altheiban, Yazeed Ibrahim; Aldosari, Mohammed Saud; Almudarra, Nawaf Faleh; Alwabel, Sulaiman Ali

    2015-01-01

    Background Occupational and environmental exposure to petroleum refinery products poses a great threat to human health. This study aimed to assess the lung function and Fractional Exhaled Nitric Oxide (FeNO) among petroleum refinery workers. Methods In this cross-sectional study, 112 participants (56 petroleum refinery workers with mean age 35.20 ± 1.62 years, and 56 age, weight, height, ethnicity and socioeconomically matched control subjects with mean age 30.02 ± 1.76 years) were recruited....

  16. Nitric oxide in exhaled and aspirated nasal air as an objective measure of human response to indoor air pollution

    Kolarik, Barbara; Lagercrantz, L.; Sundell, Jan

    2009-01-01

    NO analyzer. Sixteen healthy female subjects were exposed to two indoor air pollutants and to a clean reference condition for 4.5 h. Subjective assessments of the environment were obtained by questionnaires. After exposure (4.5 h) to the two polluted conditions a small increase in NO concentration in......The concentration of nitric oxide (NO) in exhaled and aspirated nasal air was used to objectively assess human response to indoor air pollutants in a climate chamber exposure experiment. The concentration of NO was measured before exposure, after 2, and 4.5 h of exposure, using a chemiluminescence...... exhaled air was observed. After exposure to the reference condition the mean NO concentration was significantly reduced compared to pre-exposure. Together these changes resulted in significant differences in exhaled NO between exposure to reference and polluted conditions. NO in nasal air was not affected...

  17. Exhaled nitric oxide levels in childhood asthma: a more reliable indicator of asthma severity than lung function measurement?

    Piacentini, G L; Suzuki, Y; Bodini, A

    2000-04-01

    The level of exhaled nitric oxide (NO) has been demonstrated to reflect the degree of airway inflammation in patients with asthma and to be related to the severity of asthma, as well as to the efficacy of treatment. In contrast, lung function tests provide information about airway volumes and flows reflecting the level of airway obstruction, but do not allow any direct information about the degree of airway inflammation. Several studies have evaluated the relationships between the level of airway inflammation assessed by exhaled NO and the levels of airway obstruction and/or bronchial hyperresponsiveness in asthmatic adults and children. These studies highlight the complex pathophysiology of asthma and suggest that exhaled NO may have a promising role in addition to lung function measurement in the evaluation of asthma severity in children. PMID:18034534

  18. Indoor Airflow Patterns, Dispersion of Human Exhalation Flow and Risk of Airborne Cross-Infection between People in a Room

    Olmedo, Inés

    in the air. These tiny particles or droplet nuclei can follow the air flow pattern in the room and produce high contaminant concentration in different areas of the indoor environment. This fact can provoke a high exposure to exhaled contaminants and a risk of cross-infection to a susceptible person...... situated in the same room. Abundant evidence shows that the air flow distribution systems play a crucial role in the dispersion of these human exhaled contaminants. However, there are many parameters that influence the cross-infection risk between people situated close to each other in a ventilated room......-environment around the persons. This thesis analyzes some of these parameters in the influence of cross-infection risk between two people in a room, which are simulated by two breathing thermal manikins. One of the manikins is considered the source of contaminants, which is exhaling contaminated air through the...

  19. The Analysis of the Exhaled Nitric Oxide in a Group of Patients with Asthma, Aged 3-18

    Pirogowicz Iwona

    2014-12-01

    Full Text Available The aim of this study was to analyse the results of exhaled nitric oxide examination in a group of patients with hyper-responsive-ness. The study was performed on a group of 297 children who underwent spirometry, examination of exhaled nitric oxide, skin prick test and stress probe in years 2010-2012 in Pulmonology and Allergy Centre in Karpacz. Mean age of patients was 11.86. Patients were divided into four groups: with diagnosed asthma, with bronchial hyper-responsiveness (BHR, with described asthma without BHR and a group with BHR without diagnosed asthma. The results of the study confirmed the presence of high-er amount of exhaled nitric oxide in patients with asthma and bronchial hyper-responsiveness. The elevation of NO concen-tration correlated with age; there was no significant difference between sexes.

  20. Seasonal variations of natural ventilation and radon-222 exhalation in a slightly rising dead-end tunnel

    Perrier, Frederic [Equipe de Geomagnetisme, Institut de Physique du Globe de Paris UMR7154 et universite Denis-Diderot Paris VII, 4 Place Jussieu, 75005 Paris (France)], E-mail: perrier@ipgp.jussieu.fr; Richon, Patrick [Equipe Geologie des Systemes Volcaniques, Institut de Physique du Globe de Paris UMR7154, 4 Place Jussieu, 75005 Paris (France); Laboratoire Hydrogeochimie et Etudes de sites, Departement Analyse Surveillance Environnement, Commissariat a l' energie atomique, F-91680 Bruyeres-le-Chatel (France); Gautam, Umesh; Tiwari, Dilli Ram; Shrestha, Prithvi; Sapkota, Soma Nath [National Seismic Centre, Department of Mines and Geology, Lainchaur, Kathmandu (Nepal)

    2007-10-15

    The concentration activity of radon-222 has been monitored, with some interruptions, from 1997 to 2005 in the end section of a slightly rising, dead-end, 38-m long tunnel located in the Phulchoki hill, near Kathmandu, Nepal. While a high concentration varying from 6 x 10{sup 3} Bq m{sup -3} to 10 x 10{sup 3} Bq m{sup -3} is observed from May to September (rainy summer season), the concentration remains at a low level of about 200 Bq m{sup -3} from October to March (dry winter season). This reduction of radon concentration is associated with natural ventilation of the tunnel, which, contrary to expectations for a rising tunnel, takes place mainly from October to March when the outside air temperature drops below the average tunnel temperature. This interpretation is supported by temperature measurements in the atmosphere of the tunnel, a few meters away from the entrance. The temporal variations of the diurnal amplitude of this temperature indeed follow the ventilation rate deduced from the radon measurements. In the absence of significant ventilation (summer season), the radon exhalation flux at the rock surface into the tunnel atmosphere can be inferred; it exhibits a yearly variation with additional transient reductions associated with heavy rainfall, likely to be due to water infiltration. No effect of atmospheric pressure variations on the radon concentration is observed in this tunnel. This experiment illustrates how small differences in the location and geometry of a tunnel can lead to vastly different behaviours of the radon concentration versus time. This observation has consequences for the estimation of the dose rate and the practicability of radon monitoring for tectonic purposes in underground environments.

  1. Seasonal variations of natural ventilation and radon-222 exhalation in a slightly rising dead-end tunnel

    The concentration activity of radon-222 has been monitored, with some interruptions, from 1997 to 2005 in the end section of a slightly rising, dead-end, 38-m long tunnel located in the Phulchoki hill, near Kathmandu, Nepal. While a high concentration varying from 6 x 103 Bq m-3 to 10 x 103 Bq m-3 is observed from May to September (rainy summer season), the concentration remains at a low level of about 200 Bq m-3 from October to March (dry winter season). This reduction of radon concentration is associated with natural ventilation of the tunnel, which, contrary to expectations for a rising tunnel, takes place mainly from October to March when the outside air temperature drops below the average tunnel temperature. This interpretation is supported by temperature measurements in the atmosphere of the tunnel, a few meters away from the entrance. The temporal variations of the diurnal amplitude of this temperature indeed follow the ventilation rate deduced from the radon measurements. In the absence of significant ventilation (summer season), the radon exhalation flux at the rock surface into the tunnel atmosphere can be inferred; it exhibits a yearly variation with additional transient reductions associated with heavy rainfall, likely to be due to water infiltration. No effect of atmospheric pressure variations on the radon concentration is observed in this tunnel. This experiment illustrates how small differences in the location and geometry of a tunnel can lead to vastly different behaviours of the radon concentration versus time. This observation has consequences for the estimation of the dose rate and the practicability of radon monitoring for tectonic purposes in underground environments

  2. Experimental Study of the Cross-infection Risk due to the Cross-flow of Exhaled Airflows and a Plane Jet with the Protected Occupied Zone Ventilation

    Cao, Guangyu; Nielsen, Peter Vilhelm; Xu, Chunwen;

    2014-01-01

    The objective of this study is to determine how the cross infection risk can be minimized between two persons with a plane jet of the protected occupied zone ventilation (POV) system. The exhaled air of infected people can be one of the sources of infectious respiratory viruses and bacteria....... The infectious exhaled air may from the respiratory activities such as the breathing, coughing, sneezing, and talking. A plane jet was formed in the POV system to separate the room into a source zone and a target zone in a climate chamber, in which tow breathing thermal manikins are employed to produce breathing...... airflows. The exhaled air velocity and the downward jet velocity were measured at a frequency of 10 Hz, by which the maximum velocity of exhaled airflow can be obtained. In this study, the promising results show that the downward plane jet of POV system can break the exhalation airflow from the source...

  3. Terahertz Chemical Analysis of Exhaled Human Breath - Broad Essay of Chemicals

    Branco, Daniela R.; Fosnight, Alyssa M.; Thomas, Jessica R.; Medvedev, Ivan R.

    2013-06-01

    Approximately 3000 chemicals are thought to be present in human breath. Of these chemicals, many are considered typical of exhaled air. Yet, others can allude to different disease pathologies. The detection of chemicals in breath could have many practical purposes in medicine and provide a noninvasive means of diagnostics. We have previously reported on detection of ethanol, methanol, and acetone in exhaled human breath using a novel sub-millimeter/THz spectroscopic approach. This paper reports on our most recent study. A tentative list has been made of approximately 20 chemicals previously found in breath using other methods. Though many of these chemicals are only expressed in samples from donors with certain pathologies, at the time of this submission we are able to detect and quantitatively measure acetaldehyde and dimethyl sulfide in the breath of several healthy donors. Additional tentatively identified chemicals have been seen using this approach. This presentation will explain our experimental procedures and present our most recent results in THz breath analysis. Prospects, challenges and future plans will be outlined and discussed.

  4. Study of the exhaled acetone in type 1 diabetes using quantum cascade laser spectroscopy.

    Reyes-Reyes, Adonis; Horsten, Roland C; Urbach, H Paul; Bhattacharya, Nandini

    2015-01-01

    The acetone concentration exhaled in the breath of three type 1 diabetes patients (two minors and one adult) and one healthy volunteer is studied using a quantum cascade laser-based spectroscopic system. Using the acetone signature between 1150 and 1250 cm(-1) and a multiline fitting method, the concentration variations on the order of parts per billion by volume were measured. Blood glucose and ketone concentrations in blood measurements were performed simultaneously to study their relation with acetone in exhaled breath. We focus on personalized studies to better understand the role of acetone in diabetes. For each volunteer, we performed a series of measurements over a period of time, including overnight fastings of 11 ± 1 h and during ketosis-hyperglycemia events for the minors. Our results highlight the importance of performing personalized studies because the response of the minors to the presence of ketosis was consistent but unique for each individual. Also, our results emphasize the need for performing more studies with T1D minors, because the acetone concentration in the breath of the minors differs, with respect to those reported in the literature, which are based on adults. PMID:25506743

  5. Endogenous CO monitoring in exhalation with tunable diode lasers: applications to clinical and biomedical diagnostics

    Stepanov, Eugene V.; Zyrianov, Pavel V.; Miliaev, Valerii A.; Shulagin, Yurii A.; D'yachenko, Alexander I.

    1999-07-01

    Middle IR tunable diode lasers were applied to studies of pulmonary excretion of endogenous carbon monoxide (CO). Variations of the CO content level in exhaled air of healthy nonsmokers were investigated for different environmental conditions with the applied laser technique. Correlation of the obtained data with atmospheric CO contamination and elevated oxygen content were studied as well as diurnal variations of the endogenous CO in exhalation was observed. Criteria for correct conditions of the endogenous CO detection in breath could be derive don this basis. Developed laser approach and methods were applied for the analysis of the excreted CO level in different diseases like bronchial asthma, cystic fibrosis, idiopathic pulmonary fibrosis, chronic obstructive pulmonary disease, anemia and hepatitis. Laser based close-to-real-time monitoring of the endogenous CO elimination with breath in the course of different dynamic tests was demonstrated to be informative in studies of blood oxygen transport and pH variations in tissues for different challenges tests in human physiology.

  6. The validity of tympanic and exhaled breath temperatures for core temperature measurement

    We examined the efficacy of tympanic (Tty) and exhaled breath (TX) temperatures as indices of rectal temperature (Tre) by applying heat (condition A) and cold (condition B) in a dynamic A-B-A-B sequence. Fifteen healthy adults (8 men; 7 women; 24.9 ± 4.6 years) volunteered. Following a 15 min baseline period, participants entered a water tank maintained at 42 °C water temperature and passively rested until their Tre increased by 0.5 °C above baseline. Thereafter, they entered a different water tank maintained at 12 °C water temperature until their Tre decreased by 0.5 °C below baseline. This procedure was repeated twice (i.e. A-B-A-B). Tty demonstrated moderate response delays to the repetitive changes in thermal balance, whereas TX and Tre responded relatively fast. Both Tty and TX correlated significantly with Tre (P < 0.05). Linear regression models were used to predict Tre based on Tty and TX. The predicted values from both models correlated significantly with Tre (P < 0.05) and followed the changes in Tre during the A-B-A-B thermal protocol. While some mean differences with Tre were observed (P < 0.05), the 95% limits of agreement were acceptable for both models. It is concluded that the calculated models based on tympanic and exhaled breath temperature are valid indicators of core temperature. (note)

  7. Fixation, retention and exhalation of carrier-free 11C-labelled carbon monoxide by man

    Carrier-free 11C-labelled carbon monoxide was produced by proton irradiation of a nitrogen gas flow target via the 14N(p,α)11C process followed by on-line reduction of the predominantly formed 11C-carbon dioxide with a yield of 0.4 mCi/μAmin. After appropriate quality control about 2 mCi of carrier-free 11C-carbon monoxide in 500 ml of nitrogen gas were inhaled by test subjects in one breath. The 11C-activity distribution was then followed in vivo by scanning above thorax, head, liver, thigh and os sacrum; simultaneously the 11C-activity of the blood was also followed by batch measurement. The data indicate that part of the 11C-activity migrates from the blood into the intercellular space, while another part is exhaled. The 11C-activity leaves the individual organs with a biological half-life ranging from about 120 to 200 min, a time which is short as compared to the one observed for 51Cr-labelled erythrocytes. A radio gas chromatographic analysis of the exhaled air showed that the 11C-activity leaves the body exclusively in the form of 11C-labelled carbon monoxide. Consequently, metabolism of the 11CO into 11Co2 or other compounds can be excluded. (orig.)

  8. Exhaled breath condensate pH and hydrogen peroxide as non-invasive markers for asthma

    Objective was to estimate the predictive value of exhaled breath condensate (EBC) hydrogen peroxide (H2O2) concentration and pH as non-invasive markers in asthma. Fifty patients with unstable, steroid naive atopic asthma were included in this study, 25 with persistent asthma. Asthma diagnosis was according to the National Heart Lung and Blood Institute guidelines for the diagnosis and management of asthma. Forced expiratory volume in one second (FEV1) was measured by computerized spirometry. The EBC H2O2 assay was carried out using the colorimetric assay. The study was conducted from January to December 2005 in the Asthma and Allergy Center, Tikrit, Iraq. The EBC H2O2 concentration was higher in the asthmatic group (0.91mol) as compared with the control (0.23 mol). There was inverse correlation between EBC H2O2 concentration and FEV1 predicted percent for asthmatic patients. The mean EBC pH was lower in the asthmatic than the control group. There was a positive correlation between EBC pH and FEV 1 predicted percent for asthmatic patients. There was an inverse correlation between EBC H2O2 concentration and pH for all asthmatic patients, intermittent, and persistent asthmatic group. Exhaled breath condensate hydrogen peroxide concentration and pH was a good non-invasive marker for asthma, whether it was with a persistent or intermittent course. (author)

  9. Venous gas emboli and exhaled nitric oxide with simulated and actual extravehicular activity.

    Karlsson, Lars L; Blogg, S Lesley; Lindholm, Peter; Gennser, Mikael; Hemmingsson, Tryggve; Linnarsson, Dag

    2009-10-01

    The decompression experienced due to the change in pressure from a space vehicle (1013hPa) to that in a suit for extravehicular activity (EVA) (386hPa) was simulated using a hypobaric chamber. Previous ground-based research has indicated around a 50% occurrence of both venous gas emboli (VGE) and symptoms of decompression illness (DCI) after similar decompressions. In contrast, no DCI symptoms have been reported from past or current space activities. Twenty subjects were studied using Doppler ultrasound to detect any VGE during decompression to 386hPa, where they remained for up to 6h. Subjects were supine to simulate weightlessness. A large number of VGE were found in one subject at rest, who had a recent arm fracture; a small number of VGE were found in another subject during provocation with calf contractions. No changes in exhaled nitric oxide were found that can be related to either simulated EVA or actual EVA (studied in a parallel study on four cosmonauts). We conclude that weightlessness appears to be protective against DCI and that exhaled NO is not likely to be useful to monitor VGE. PMID:19442591

  10. Radon soil-gas concentration and exhalation from mine tailings dams in South Africa

    In Africa as well as in the world, South Africa plays an important role in the mining industry which dates back almost 120 years. Mining activities in South Africa mainly take place in Gauteng Province. Every year million of tons of rocks are taken from underground, milled and processed to extract gold. The uranium bearing tailings are disposed in dumpsites. These tailings dumps contain considerable amounts of radium (226Ra) and have therefore been identified as large sources of radon (222Rn). Radon is a noble gas formed by the decay of radium which in turn is derived from the radioactive decay of uranium (238U). Radon release from these tailings dumps pose health concerns for the surrounding communities. Radon soil gas concentrations and exhalations from a non-operational mine dump (Kloof) which belongs to Carletonville Gold Field, Witwatersrand, South Africa have been investigated. The continuous radon monitor, the Durridge RAD7 was used to measure 222Rn soil gas concentration in the tailings dump at five different spots. The radon soil gas concentration levels were measured at depths starting from 30 cm below ground/air interface up to 110 cm at intervals of 20 cm. The concentrations recorded ranged from 26±1 to 472±23 kBq.m-3. Furthermore, thirty four soil samples were taken from the spots where radon soil gas measurements were measured for laboratory-based measurement using the low background Hyper Pure Germanium (HPGe) gamma-ray detector available at the Environmental Radioactivity Laboratory (ERL), iThemba LABS, Western Cape Province. The soil samples were collected in the depth range 0-30 cm. After analysis the weighted average activity concentrations in the soils samples were 308±7 Bq.kg-1, 255±5 Bq.kg-1 and 18±1 Bq.kg-1 for 238U, 40K and 232Th, respectively. A number of factors such as the radium activity concentration and its distribution in soil grains, soil grain size, soil porosity, temperature, moisture and atmospheric pressure influence radon

  11. Radon soil-gas concentration and exhalation from mine tailings dams in South Africa

    Ongori, J.; Lindsay, R. [University of the Western Cape, Department of Physics, Private Bag X17, Bellville 7535 (South Africa); Newman, R. [Stellenbosch University, Department of Physics, Private Bag X1 Matieland 7602 (South Africa); Maleka, P. [iThemba LABS, Department of Nuclear Physics, P. O. Box 722, Somerset West 7129 (South Africa)

    2014-07-01

    In Africa as well as in the world, South Africa plays an important role in the mining industry which dates back almost 120 years. Mining activities in South Africa mainly take place in Gauteng Province. Every year million of tons of rocks are taken from underground, milled and processed to extract gold. The uranium bearing tailings are disposed in dumpsites. These tailings dumps contain considerable amounts of radium ({sup 226}Ra) and have therefore been identified as large sources of radon ({sup 222}Rn). Radon is a noble gas formed by the decay of radium which in turn is derived from the radioactive decay of uranium ({sup 238}U). Radon release from these tailings dumps pose health concerns for the surrounding communities. Radon soil gas concentrations and exhalations from a non-operational mine dump (Kloof) which belongs to Carletonville Gold Field, Witwatersrand, South Africa have been investigated. The continuous radon monitor, the Durridge RAD7 was used to measure {sup 222}Rn soil gas concentration in the tailings dump at five different spots. The radon soil gas concentration levels were measured at depths starting from 30 cm below ground/air interface up to 110 cm at intervals of 20 cm. The concentrations recorded ranged from 26±1 to 472±23 kBq.m{sup -3}. Furthermore, thirty four soil samples were taken from the spots where radon soil gas measurements were measured for laboratory-based measurement using the low background Hyper Pure Germanium (HPGe) gamma-ray detector available at the Environmental Radioactivity Laboratory (ERL), iThemba LABS, Western Cape Province. The soil samples were collected in the depth range 0-30 cm. After analysis the weighted average activity concentrations in the soils samples were 308±7 Bq.kg{sup -1}, 255±5 Bq.kg{sup -1} and 18±1 Bq.kg{sup -1} for {sup 238}U, {sup 40}K and {sup 232}Th, respectively. A number of factors such as the radium activity concentration and its distribution in soil grains, soil grain size, soil porosity

  12. Effect of Inhaled Budesonide on Interleukin-4 and Interleukin-6 in Exhaled Breath Condensate of Asthmatic Patients

    Chun-Hua Chi; Ji-Ping Liao; Yan-Ni Zhao; Xue-Ying Li; Guang-Fa Wang

    2016-01-01

    Background:Studies ofinterleukin (IL)-4 and IL-6 in the exhaled breath condensate (EBC) of asthmatic patients are limited.This study was to determine the effect of inhaled corticosteroid (ICS) treatment on IL-4 and IL-6 in the EBC of asthmatic patients.Methods:In a prospective,open-label study,budesonide 200 μg twice daily by dry powder inhaler was administered to 23 adult patients with uncontrolled asthma (mean age 42.7 years) for 12 weeks.Changes in asthma scores,lung function parameters (forced expiratory volume in 1 s [FEV1],peak expiratory flow [PEF],forced expiratory flow at 50% of forced vital capacity [FEF50],forced expiratory flow at 75% of forced vital capacity,maximum mid-expiratory flow rate) and the concentrations of IL-4 and IL-6 in EBC were measured.Results:Both asthma scores and lung function parameters were significantly improved by ICS treatment.The mean IL-4 concentration in the EBC was decreased gradually,from 1.92 ± 0.56 pmol/L before treatment to 1.60 ± 0.36 pmol/L after 8 weeks of treatment (P < 0.05) and 1.54 ± 0.81 pmol/L after 12 weeks of treatment (P < 0.01).However,the IL-6 concentration was not significantly decreased.The change in the IL-4 concentration was correlated with improvements in mean FEV1,PEF and FEF50 values (correlation coefficients-0.468,-0.478,and-0.426,respectively).Conclusions:The concentration of IL-4 in the EBC of asthmatic patients decreased gradually with ICS treatment.Measurement of IL-4 in EBC could be useful to monitor airway inflammation in asthmatics.

  13. Secondary electrospray ionization coupled to high-resolution mass spectrometry reveals tryptophan pathway metabolites in exhaled human breath.

    García-Gómez, Diego; Gaisl, Thomas; Bregy, Lukas; Martínez-Lozano Sinues, Pablo; Kohler, Malcolm; Zenobi, Renato

    2016-06-30

    Many studies and personalized medicine in general require frequent measurements and/or rapid results of biomarker levels. Here we show that 20 low volatility metabolites of the tryptophan pathway can be detected in exhaled human breath. This real-time and non-invasive method offers an attractive alternative to blood analysis. PMID:27273568

  14. Wearable Personal Exhaust Ventilation, WPEV: Improved Indoor Air Quality and Reduced Exposure to Air Exhaled from a Sick Doctor

    Bolashikov, Zhecho D.; Barova, Maria; Melikov, Arsen K.

    2015-01-01

    Exposure reduction to exhaled air from a sick doctor wearing a personal exhaust unit incorporated in a headset-microphone was studied. Experiments were performed in a full-scale test room furnished as a double-bed hospital room with overhead ventilation at 3, 6, and 12 air changes per hour. Room...

  15. Oxidative Stress Markers Are Elevated in Exhaled Breath Condensate of Workers Exposed to Nanoparticles during Iron Oxide Pigment Production.

    Pelclová, D.; Ždímal, Vladimír; Kačer, P.; Fenclová, Z.; Vlčková, Š.; Syslová, K.; Navrátil, Tomáš; Schwarz, Jaroslav; Zíková, Naděžda; Barošová, H.; Turci, F.; Komarc, M.; Pelcl, T.; Běláček, J.; Kukutschová, J.; Zakharov, S.

    2016-01-01

    Roč. 10, č. 1 (2016), s. 016004. ISSN 1752-7155 Institutional support: RVO:67985858 ; RVO:61388955 Keywords : nanoparticles * exhaled breath condensate * oxidative stress * urine * occupational exposure * Fe2O3 * Fe3O4 Subject RIV: DN - Health Impact of the Environment Quality; CF - Physical ; Theoretical Chemistry (UFCH-W) Impact factor: 4.631, year: 2014

  16. Indoor Airflow Patterns, Dispersion of Human Exhalation Flow and Risk of Airborne Cross-infection between People in a Room

    Olmedo, Inés

    -environment around the persons. This thesis analyzes some of these parameters in the influence of cross-infection risk between two people in a room, which are simulated by two breathing thermal manikins. One of the manikins is considered the source of contaminants, which is exhaling contaminated air through the...... within this thesis....

  17. Exhaled breath hydrogen cyanide as a marker of early Pseudomonas aeruginosa infection in children with cystic fibrosis

    Francis J. Gilchrist

    Full Text Available Hydrogen cyanide is readily detected in the headspace above Pseudomonas aeruginosa cultures and in the breath of cystic fibrosis (CF patients with chronic (P. aeruginosa infection. We investigated if exhaled breath HCN is an early marker of P. aeruginosa infection. 233 children with CF who were free from P. aeruginosa infection were followed for 2 years. Their median (interquartile range age was 8.0 (5.0–12.2 years. At each study visit, an exhaled breath sample was collected for hydrogen cyanide analysis. In total, 2055 breath samples were analysed. At the end of the study, the hydrogen cyanide concentrations were compared to the results of routine microbiology surveillance. P. aeruginosa was isolated from 71 children during the study with an incidence (95% CI of 0.19 (0.15–0.23 cases per patient-year. Using a random-effects logistic model, the estimated odds ratio (95% CI was 3.1 (2.6–3.6, which showed that for a 1- ppbv increase in exhaled breath hydrogen cyanide, we expected a 212% increase in the odds of P. aeruginosa infection. The sensitivity and specificity were estimated at 33% and 99%, respectively. Exhaled breath hydrogen cyanide is a specific biomarker of new P. aeruginosa infection in children with CF. Its low sensitivity means that at present, hydrogen cyanide cannot be used as a screening test for this infection.

  18. Predicting airway hyperreactivity to mannitol using exhaled nitric oxide in an unselected sample of adolescents and young adults

    Sverrild, A; Malinovschi, A; Porsbjerg, C; Backer, V; Alving, K

    2013-01-01

    Increased levels of exhaled nitric oxide (FeNO) and airway hyperresponsiveness (AHR) to inhaled mannitol are related to allergic inflammation characterized by eosinophil infiltration and a clinical response to treatment with anti-inflammatory agents in subjects with asthma. This study determines...

  19. Determination of cysteinyl leukotrienes in exhaled breath condensate: Method combining immunoseparation with LC-ESI-MS/MS

    Syslová, K.; Kačer, P.; Vilhanová, B.; Kuzma, Marek; Lipovová, P.; Fenclová, Z.; Lebedová, J.; Pelclová, D.

    2011-01-01

    Roč. 879, č. 23 (2011), s. 2220-2228. ISSN 1570-0232 R&D Projects: GA MZd NS10298 Keywords : Cysteinyl leukotriene * Exhaled breath condensate * Immunoseparation Subject RIV: CE - Biochemistry Impact factor: 2.888, year: 2011

  20. Instant effects of changing body positions on compositions of exhaled breath.

    Sukul, Pritam; Trefz, Phillip; Kamysek, Svend; Schubert, Jochen K; Miekisch, Wolfram

    2015-12-01

    Concentrations of exhaled volatile organic compounds (VOCs) may depend not only on biochemical or pathologic processes but also on physiological parameters. As breath sampling may be done in different body positions, effects of the sampling position on exhaled VOC concentrations were investigated by means of real-time mass spectrometry. Breaths from 15 healthy volunteers were analyzed in real-time by PTR-ToF-MS-8000 during paced breathing (12/min) in a continuous side-stream mode. We applied two series of body positions (setup 1: sitting, standing, supine, and sitting; setup 2: supine, left lateral, right lateral, prone, and supine). Each position was held for 2 min. Breath VOCs were quantified in inspired and alveolar air by means of a custom-made algorithm. Parallel monitoring of hemodynamics and capnometry was performed noninvasively. In setup 1, when compared to the initial sitting position, normalized mean concentrations of isoprene, furan, and acetonitrile decreased by 24%, 26%, and 9%, respectively, during standing and increased by 63%, 36%, and 10% during lying mirroring time profiles of stroke volume and pET-CO2. In contrast, acetone and H2S concentrations remained almost constant. In setup 2, when compared to the initial supine position, mean alveolar concentrations of isoprene and furan increased significantly up to 29% and 16%, respectively, when position was changed from lying on the right side to the prone position. As cardiac output and stroke volume decreased at that time, the reasons for the observed concentrations changes have to be linked to the ventilation/perfusion ratio or compartmental distribution rather than to perfusion alone. During final postures, all VOC concentrations, hemodynamics, and pET-CO2 returned to baseline. Exhaled blood-borne VOC profiles changed due to body postures. Changes depended on cardiac stroke volume, origin, compartmental distribution and physico-chemical properties of the substances. Patients' positions and

  1. Age dependent hit probabilities for lung cancer induction following exhalation of ingested radon

    Previous calculations of the risk following ingestion of 222Rn (radon) in drinking water have been concerned primarily with the solubilization of the radon in body tissues, followed by in situ decay. Much less attention has been directed towards the escape of radon from lung tissue and blood into the alveolar air, which should lead to doses to lung tissue as the newly formed progeny deposit in lung passages prior to exhalation. The present report details the calculation of hit probabilities to the basal cells of the bronchial epithelium and alveolar cells in various age groups following ingestion of radon in drinking water. Results are compared with those obtained for the in situ decay of radon within the lung mass. (author)

  2. Exhaled breath condensate pH as a biomarker of COPD severity in ex-smokers

    Alchanatis Manos

    2011-05-01

    Full Text Available Abstract Endogenous airway acidification, as assessed by exhaled breath condensate (EBC pH, is present in patients with stable COPD. The aim of this study was to measure EBC pH levels in a large cohort of COPD patients and to evaluate associations with functional parameters according to their smoking status. EBC was collected from 161 patients with stable COPD and 112 controls (current and ex-smokers. EBC pH was measured after Argon deaeration and all subjects underwent pulmonary function testing. EBC pH was lower in COPD patients compared to controls [7.21 (7.02, 7.44 vs. 7.50 (7.40, 7.66; p Endogenous airway acidification is related to disease severity and to parameters expressing hyperinflation and air trapping in ex-smokers with COPD. The possible role of EBC pH in COPD needs to be further evaluated in longitudinal studies.

  3. The establishment of a portable high sensitivity exhaled thoron activity measurement system

    A portable system, using electrostatic collection, for the measurement of exhaled thoron activity in humans is described, together with the basic theory, equipment, calibration procedures, measurement and the preliminary use. The portable system built on experience at the Argonne National Laboratory to achieve a reduction in measurement time from 30 hours to 200 minutes, and to increase the total efficiency of the system from 50%(ANL) to 55% with a minimum detection limit decreased to 0.007 Bq (zero activity± σ). The total standard error of this system is 47% for a thorium lung burden of 0.22 Bq. The average background of this scintillation detector was 0.003 counts/min. (author)

  4. Clinical application of exhaled nitric oxide measurement in pediatric lung diseases

    Manna Angelo

    2012-12-01

    Full Text Available Summary Fractional exhaled nitric oxide (FeNO is a non invasive method for assessing the inflammatory status of children with airway disease. Different ways to measure FeNO levels are currently available. The possibility of measuring FeNO levels in an office setting even in young children, and the commercial availability of portable devices, support the routine use of FeNO determination in the daily pediatric practice. Although many confounding factors may affect its measurement, FeNO is now widely used in the management of children with asthma, and seems to provide significantly higher diagnostic accuracy than lung function or bronchial challenge tests. The role of FeNO in airway infection (e.g. viral bronchiolitis and common acquired pneumonia, in bronchiectasis, or in cases with diffuse lung disease is less clear. This review focuses on the most recent advances and the current clinical applications of FeNO measurement in pediatric lung disease.

  5. Exhaled breath condensate: a promising source for biomarkers of lung disease.

    Liang, Yan; Yeligar, Samantha M; Brown, Lou Ann S

    2012-01-01

    Exhaled breath condensate (EBC) has been increasingly studied as a noninvasive research method for sampling the alveolar and airway space and is recognized as a promising source of biomarkers of lung diseases. Substances measured in EBC include oxidative stress and inflammatory mediators, such as arachidonic acid derivatives, reactive oxygen/nitrogen species, reduced and oxidized glutathione, and inflammatory cytokines. Although EBC has great potential as a source of biomarkers in many lung diseases, the low concentrations of compounds within the EBC present challenges in sample collection and analysis. Although EBC is viewed as a noninvasive method for sampling airway lining fluid (ALF), validation is necessary to confirm that EBC truly represents the ALF. Likewise, a dilution factor for the EBC is needed in order to compare across subjects and determine changes in the ALF. The aims of this paper are to address the characteristics of EBC; strategies to standardize EBC sample collection and review available analytical techniques for EBC analysis. PMID:23365513

  6. Exhaled Breath Condensate: A Promising Source for Biomarkers of Lung Disease

    Yan Liang

    2012-01-01

    Full Text Available Exhaled breath condensate (EBC has been increasingly studied as a noninvasive research method for sampling the alveolar and airway space and is recognized as a promising source of biomarkers of lung diseases. Substances measured in EBC include oxidative stress and inflammatory mediators, such as arachidonic acid derivatives, reactive oxygen/nitrogen species, reduced and oxidized glutathione, and inflammatory cytokines. Although EBC has great potential as a source of biomarkers in many lung diseases, the low concentrations of compounds within the EBC present challenges in sample collection and analysis. Although EBC is viewed as a noninvasive method for sampling airway lining fluid (ALF, validation is necessary to confirm that EBC truly represents the ALF. Likewise, a dilution factor for the EBC is needed in order to compare across subjects and determine changes in the ALF. The aims of this paper are to address the characteristics of EBC; strategies to standardize EBC sample collection and review available analytical techniques for EBC analysis.

  7. Chemical Analysis of Exhaled Human Breath Using High Resolution Mm-Wave Rotational Spectra

    Guo, Tianle; Branco, Daniela; Thomas, Jessica; Medvedev, Ivan; Dolson, David; Nam, Hyun-Joo; O, Kenneth

    2014-06-01

    High resolution rotational spectroscopy enables chemical sensors that are both sensitive and highly specific, which is well suited for analysis of expired human breath. We have previously reported on detection of breath ethanol, methanol, acetone, and acetaldehyde using THz sensors. This paper will outline our present efforts in this area, with specific focus on our ongoing quest to correlate levels of blood glucose with concentrations of a few breath chemicals known to be affected by elevated blood sugar levels. Prospects, challenges and future plans will be outlined and discussed. Fosnight, A.M., B.L. Moran, and I.R. Medvedev, Chemical analysis of exhaled human breath using a terahertz spectroscopic approach. Applied Physics Letters, 2013. 103(13): p. 133703-5.

  8. Exhaled nitric oxide and urinary EPX levels in infants: a pilot study

    Olin Anna-Carin

    2011-05-01

    Full Text Available Abstract Background Objective markers of early airway inflammation in infants are not established but are of great interest in a scientific setting. Exhaled nitric oxide (FeNO and urinary eosinophilic protein X (uEPX are a two such interesting markers. Objective To investigate the feasibility of measuring FeNO and uEPX in infants and their mothers and to determine if any relations between these two variables and environmental factors can be seen in a small sample size. This was conducted as a pilot study for the ongoing Swedish Environmental Longitudinal Mother and child Asthma and allergy study (SELMA. Methods Consecutive infants between two and six months old and their mothers at children's health care centres were invited, and 110 mother-infant pairs participated. FeNO and uEPX were analysed in both mothers and infants. FeNO was analyzed in the mothers online by the use of the handheld Niox Mino device and in the infants offline from exhaled air sampled during tidal breathing. A 33-question multiple-choice questionnaire that dealt with symptoms of allergic disease, heredity, and housing characteristics was used. Results FeNO levels were reduced in infants with a history of upper respiratory symptoms during the previous two weeks (p Conclusion The use of uEPX as a marker of early inflammation was not supported. FeNO levels in infants were associated to windowpane condensation. Measuring FeNO by the present method may be an interesting way of evaluating early airway inflammation. In a major population study, however, the method is difficult to use, for practical reasons.

  9. Endothelin-1 in exhaled breath condensate of allergic asthma patients with exercise-induced bronchoconstriction

    Tomasiak Maria M

    2007-10-01

    Full Text Available Abstract Background Exercise-induced bronchoconstriction (EIB is a highly prevalent condition, whose pathophysiology is not well understood. Endothelins are proinflammatory, profibrotic, broncho- and vasoconstrictive peptides which play an important role in the development of airway inflammation and remodeling in asthma. The aim of the study was to evaluate the changes in endothelin-1 levels in exhaled breath condensate following intensive exercise in asthmatic patients. Methods The study was conducted in a group of 19 asthmatic patients (11 with EIB, 8 without EIB and 7 healthy volunteers. Changes induced by intensive exercise in the concentrations of endothelin-1 (ET-1 in exhaled breath condensate (EBC during 24 hours after an exercise challenge test were determined. Moreover, the possible correlations of these measurements with the results of other tests commonly associated with asthma and with the changes of airway inflammation after exercise were observed. Results In asthmatic patients with EIB a statistically significant increase in the concentration of ET-1 in EBC collected between 10 minutes and 6 hours after an exercise test was observed. The concentration of ET-1 had returned to its initial level 24 hours after exercise. No effects of the exercise test on changes in the concentrations of ET-1 in EBC in either asthmatic patients without EIB or healthy volunteers were observed. A statistically significant correlation between the maximum increase in ET-1 concentrations in EBC after exercise and either baseline FENO and the increase in FENO or BHR to histamine 24 hours after exercise in the groups of asthmatics with EIB was revealed. Conclusion The release of ET-1 from bronchial epithelium through the influence of many inflammatory cells essential in asthma and interactions with other cytokines, may play an important role in increase of airway inflammation which was observed after postexercise bronchoconstriction in asthmatic patients.

  10. Elevated carbon monoxide in the exhaled breath of mice during a systemic bacterial infection.

    Alan G Barbour

    Full Text Available Blood is the specimen of choice for most laboratory tests for diagnosis and disease monitoring. Sampling exhaled breath is a noninvasive alternative to phlebotomy and has the potential for real-time monitoring at the bedside. Improved instrumentation has advanced breath analysis for several gaseous compounds from humans. However, application to small animal models of diseases and physiology has been limited. To extend breath analysis to mice, we crafted a means for collecting nose-only breath samples from groups and individual animals who were awake. Samples were subjected to gas chromatography and mass spectrometry procedures developed for highly sensitive analysis of trace volatile organic compounds (VOCs in the atmosphere. We evaluated the system with experimental systemic infections of severe combined immunodeficiency Mus musculus with the bacterium Borrelia hermsii. Infected mice developed bacterial densities of ∼10(7 per ml of blood by day 4 or 5 and in comparison to uninfected controls had hepatosplenomegaly and elevations of both inflammatory and anti-inflammatory cytokines. While 12 samples from individual infected mice on days 4 and 5 and 6 samples from uninfected mice did not significantly differ for 72 different VOCs, carbon monoxide (CO was elevated in samples from infected mice, with a mean (95% confidence limits effect size of 4.2 (2.8-5.6, when differences in CO2 in the breath were taken into account. Normalized CO values declined to the uninfected range after one day of treatment with the antibiotic ceftriaxone. Strongly correlated with CO in the breath were levels of heme oxygenase-1 protein in serum and HMOX1 transcripts in whole blood. These results (i provide further evidence of the informativeness of CO concentration in the exhaled breath during systemic infection and inflammation, and (ii encourage evaluation of this noninvasive analytic approach in other various other rodent models of infection and for utility in

  11. Increase of methanol in exhaled breath quantified by SIFT-MS following aspartame ingestion.

    Španěl, Patrik; Dryahina, Kseniya; Vicherková, Petra; Smith, David

    2015-12-01

    Aspartame, methyl-L-α-aspartyl-L-phenylalaninate, is used worldwide as a sweetener in foods and drinks and is considered to be safe at an acceptable daily intake (ADI) of 40 mg per kg of body weight. This compound is completely hydrolyzed in the gastrointestinal tract to aspartic acid, phenylalanine and methanol, each being toxic at high levels. The objective of the present study was to quantify the volatile methanol component in the exhaled breath of ten healthy volunteers following the ingestion of a single ADI dose of aspartame. Direct on-line measurements of methanol concentration were made in the mouth and nose breath exhalations using selected ion flow tube mass spectrometry, SIFT-MS, several times before aspartame ingestion in order to establish individual pre-dose (baseline) levels and then during two hours post-ingestion to track their initial increase and subsequent decrease. The results show that breath methanol concentrations increased in all volunteers by 1082   ±   205 parts-per-billion by volume (ppbv) from their pre-ingestion values, which ranged from 193 to 436 ppbv to peak values ranging from 981-1622 ppbv, from which they slowly decreased. These observations agree quantitatively with a predicted increase of 1030 ppbv estimated using a one-compartment model of uniform dilution of the methanol generated from a known amount of aspartame throughout the total body water (including blood). In summary, an ADI dose of aspartame leads to a 3-6 fold increase of blood methanol concentration above the individual baseline values. PMID:26582819

  12. Real time detection of exhaled human breath using quantum cascade laser based sensor technology

    Tittel, Frank K.; Lewicki, Rafal; Dong, Lei; Liu, Kun; Risby, Terence H.; Solga, Steven; Schwartz, Tim

    2012-02-01

    The development and performance of a cw, TE-cooled DFB quantum cascade laser based sensor for quantitative measurements of ammonia (NH3) and nitric oxide (NO) concentrations present in exhaled breath will be reported. Human breath contains ~ 500 different chemical species, usually at ultra low concentration levels, which can serve as biomarkers for the identification and monitoring of human diseases or wellness states. By monitoring NH3 concentration levels in exhaled breath a fast, non-invasive diagnostic method for treatment of patients with liver and kidney disorders, is feasible. The NH3 concentration measurements were performed with a 2f wavelength modulation quartz enhanced photoacoustic spectroscopy (QEPAS) technique, which is suitable for real time breath measurements, due to the fast gas exchange inside a compact QEPAS gas cell. A Hamamatsu air-cooled high heat load (HHL) packaged CW DFB-QCL is operated at 17.5°C, targeting the optimum interference free NH3 absorption line at 967.35 cm-1 (λ~10.34 μm), with ~ 20 mW of optical power. The sensor architecture includes a reference cell, filled with a 2000 ppmv NH3 :N2 mixture at 130 Torr, which is used for absorption line-locking. A minimum detection limit (1σ) for the line locked NH3 sensor is ~ 6 ppbv (with a 1σ 1 sec time resolution of the control electronics). This NH3 sensor was installed in late 2010 and is being clinically tested at St. Luke's Hospital in Bethlehem, PA.

  13. A follow-up study on indoor 222Rn, 220Rn their decay product concentrations in a mineralised zone of Himachal Pradesh, India.

    Bajwa, B S; Singh, Parminder; Singh, Prabhjot; Saini, Komal; Singh, Surinder; Sahoo, B K; Sapra, B K

    2016-03-01

    A follow-up study was taken up in a mineralised zone situated in Hamirpur district, Himachal Pradesh, India, to investigate high values of radon concentrations reported in past studies as well to update the old radon data based on bare SSNTD technique. In the present investigation, the concentrations of indoor radon, thoron and their decay products have been measured using the newly developed radon/thoron discriminating diffusion chamber with single entry face, direct radon and thoron progeny sensors (DRPS/DTPS), respectively. The measurements have been carried out in 75 dwellings of 14 different villages where the previous studies were carried out using bare SSNTD technique. It was observed that high values of earlier reported radon concentrations were mainly due to thoron interference in the Solid State Nuclear Track Detector (LR-115 type II) exposed in bare mode. Now, the average concentration values and the estimated annual inhalation dose in these villages have been found to be within the reference level as recommended by the ICRP. The annual average indoor radon and thoron concentrations observed in these dwellings have been found to vary from 44±12 to 157±73 Bq m(-3) and 44±11 to 240±125 Bq m(-3), respectively. The equilibrium equivalent concentrations of radon and thoron decay products have been observed to be in the range of 10 to 63 and 1 to 5 Bq m(-3), respectively. PMID:26184660

  14. A follow-up study on indoor 222Rn, 220Rn their decay product concentrations in a mineralised zone of Himachal Pradesh, India

    A follow-up study was taken up in a mineralised zone situated in Hamirpur district, Himachal Pradesh, India, to investigate high values of radon concentrations reported in past studies as well to update the old radon data based on bare SSNTD technique. In the present investigation, the concentrations of indoor radon, thoron and their decay products have been measured using the newly developed radon/thoron discriminating diffusion chamber with single entry face, direct radon and thoron progeny sensors (DRPS/DTPS), respectively. The measurements have been carried out in 75 dwellings of 14 different villages where the previous studies were carried out using bare SSNTD technique. It was observed that high values of earlier reported radon concentrations were mainly due to thoron interference in the Solid State Nuclear Track Detector (LR-115 type II) exposed in bare mode. Now, the average concentration values and the estimated annual inhalation dose in these villages have been found to be within the reference level as recommended by the ICRP. The annual average indoor radon and thoron concentrations observed in these dwellings have been found to vary from 44±12 to 157±73 Bq m-3 and 44±11 to 240±125 Bq m-3, respectively. The equilibrium equivalent concentrations of radon and thoron decay products have been observed to be in the range of 10 to 63 and 1 to 5 Bq m-3, respectively. (authors)

  15. Hydrogen peroxide release and acid-base status in exhaled breath condensate at rest and after maximal exercise in young, healthy subjects

    Marek E

    2009-12-01

    Full Text Available Abstract Objective Exhaled breath condensate (EBC contains among a large number of mediators hydrogen peroxide (H2O2 as a marker of airway inflammation and oxidative stress. Similarly EBC pH also changes in respiratory diseases. It was the aim of our investigation to prove if hydrogen peroxide release and changes in pH of EBC changes with exercise. Methods EBC was collected from 100 litres exhaled air along with samples of arterialized blood of 16 healthy subjects (9 males, 7 females, age 23 ± 1 years. EBC hydrogen peroxide was analyzed with EcoCheck amperometer (FILT, Berlin. The rate of H2O2 release was calculated from the concentration and collection time. pH and PCO2 in blood and in EBC were measured with the Radiometer blood gas analyzer, EBC was equilibrated with a gas mixture (5% CO2 in O2. The bicarbonate concentration was calculated according to the law of mass action for CO2 and HCO3- (pK = 6.1. Results H2O2 concentration in EBC was 190 ± 109 nmol/l, and H2O2 release at rest was 31.0 ± 18.3 pmol/min. At maximal exercise, the H2O = concentration in EBC increased to 250 ± 120 nmol/l, and H2O2 release significantly increased at maximal exercise to 84.4 ± 39.9 pmol/min (P 2 equilibrated EBC was at 6.08 ± 0.23 and the [HCO3 -] was 1.03 ± 0.40 mmol/l. At maximum exercise, pH 6.18 ± 0.17 and [HCO3-] 1.23 ± 0.30 mmol/l remained almost unaltered. Conclusions The rate of H2O2 release in EBC increased during exhausting exercise (external load: 300 Watt by a factor of 2, whereas the pH and the bicarbonate concentration of the EBC, equilibrated with 5% CO2 at 37°C were not significantly altered. It has to be proven by further experiments whether there is a linear relationship between the rates of H2O2 release in EBC in graded submaximal exercise.

  16. Leukotrienes B4, C4, D4 and E4 in the Exhaled Breath Condensate (EBC), Blood and Urine in Patients with Pneumoconiosis

    Pelclová, D.; Fenclová, Z.; Vlčková, Š.; Lebedová, J.; Syslová, K.; Pecha, O.; Běláček, J.; Navrátil, Tomáš; Kuzma, Marek; Kačer, P.

    2012-01-01

    Roč. 50, č. 4 (2012), s. 299-306. ISSN 0019-8366 Institutional support: RVO:61388955 ; RVO:61388971 Keywords : leukotrienes * Lung fibrosis * exhaled breath condensate Subject RIV: CG - Electrochemistry Impact factor: 0.870, year: 2012

  17. pH in exhaled breath condensate and nasal lavage as a biomarker of air pollution-related inflammation in street traffic-controllers and office-workers

    Thamires Marques de Lima; Cristiane Mayumi Kazama; Andreas Rembert Koczulla; Hiemstra, Pieter S.; Mariangela Macchione; Ana Luisa Godoy Fernandes; Ubiratan de Paula Santos; Maria Lucia Bueno-Garcia; Dirce Maria Zanetta; Carmen Diva Saldiva de Andre; Paulo Hilario Nascimento Saldiva; Naomi Kondo Nakagawa

    2013-01-01

    OBJECTIVE: To utilize low-cost and simple methods to assess airway and lung inflammation biomarkers related to air pollution. METHODS: A total of 87 male, non-smoking, healthy subjects working as street traffic-controllers or office-workers were examined to determine carbon monoxide in exhaled breath and to measure the pH in nasal lavage fluid and exhaled breath condensate. Air pollution exposure was measured by particulate matter concentration, and data were obtained from fixed monitoring ...

  18. pH in exhaled breath condensate and nasal lavage as a biomarker of air pollution-related inflammation in street traffic-controllers and office-workers

    de Lima, Thamires Marques; Kazama, Cristiane Mayumi; Koczulla, Andreas Rembert; Hiemstra, Pieter S.; Macchione, Mariangela; Fernandes, Ana Luisa Godoy; de Paula Santos, Ubiratan; Bueno-Garcia, Maria Lucia; Zanetta, Dirce Maria; de André, Carmen Diva Saldiva; Saldiva, Paulo Hilario Nascimento; Nakagawa, Naomi Kondo

    2013-01-01

    OBJECTIVE: To utilize low-cost and simple methods to assess airway and lung inflammation biomarkers related to air pollution. METHODS: A total of 87 male, non-smoking, healthy subjects working as street traffic-controllers or office-workers were examined to determine carbon monoxide in exhaled breath and to measure the pH in nasal lavage fluid and exhaled breath condensate. Air pollution exposure was measured by particulate matter concentration, and data were obtained from fixed monitoring st...

  19. Exhaled breath profiling using broadband quantum cascade laser-based spectroscopy in healthy children and children with asthma and cystic fibrosis.

    van Mastrigt, E; Reyes-Reyes, A; Brand, K; Bhattacharya, N; Urbach, H P; Stubbs, A P; de Jongste, J C; Pijnenburg, M W

    2016-01-01

    Exhaled breath analysis is a potential non-invasive tool for diagnosing and monitoring airway diseases. Gas chromatography-mass spectrometry and electrochemical sensor arrays are the main techniques to detect volatile organic compounds (VOC) in exhaled breath. We developed a broadband quantum cascade laser spectroscopy technique for VOC detection and identification. The objective of this study was to assess the repeatability of exhaled breath profiling with broadband quantum cascade laser-based spectroscopy and to explore the clinical applicability by comparing exhaled breath samples from healthy children with those from children with asthma or cystic fibrosis (CF). Healthy children and children with stable asthma or stable CF, aged 6-18 years, were included. Two to four exhaled breath samples were collected in Tedlar bags and analyzed by quantum cascade laser spectroscopy to detect VOCs with an absorption profile in the wavenumber region between 832 and 1262.55 cm(-1). We included 35 healthy children, 39 children with asthma and 15 with CF. Exhaled breath VOC profiles showed poor repeatability (Spearman's rho  =  0.36 to 0.46) and agreement of the complete profiles. However, we were able to discriminate healthy children from children with stable asthma or stable CF and identified VOCs that were responsible for this discrimination. Broadband quantum cascade laser-based spectroscopy detected differences in VOC profiles in exhaled breath samples between healthy children and children with asthma or CF. The combination of a relatively easy and fast method and the possibility of molecule identification makes broadband quantum cascade laser-based spectroscopy attractive to investigate the diagnostic and prognostic potential of volatiles in exhaled breath. PMID:27058305

  20. Association of Lung Inflammatory Cells with Small Airways Function and Exhaled Breath Markers in Smokers – Is There a Specific Role for Mast Cells?

    Nussbaumer-Ochsner, Yvonne; Stolk, Jan; Ferraz da Silva, Luiz F.; van Schadewijk, Annemarie; de Jeu, Ronald C.; Prins, Frans A.; Mauad, Thais; Rabe, Klaus F; Hiemstra, Pieter S.

    2015-01-01

    Background Smoking is associated with a mixed inflammatory infiltrate in the airways. We evaluated whether airway inflammation in smokers is related to lung function parameters and inflammatory markers in exhaled breath. Methods Thirty-seven smokers undergoing lung resection for primary lung cancer were assessed pre-operatively by lung function testing including single-breath-nitrogen washout test (sb-N2-test), measurement of fractional exhaled nitric oxide (FeNO) and pH/8-isoprostane in exha...

  1. Long-Term Continuous Positive Airway Pressure Therapy Normalizes High Exhaled Nitric Oxide Levels in Obstructive Sleep Apnea

    Chua, Ai-Ping; Aboussouan, Loutfi S.; Minai, Omar A.; Paschke, Kelly; Laskowski, Daniel; Dweik, Raed A.

    2013-01-01

    Study Objectives: Upper airway inflammation and oxidative stress have been implicated in the pathogenesis of obstructive sleep apnea (OSA) and may be linked to cardiovascular consequences. We prospectively examined fraction of exhaled nitric oxide (FENO), a surrogate marker of upper airway inflammation using a portable nitric oxide analyzer (NIOX MINO). Design: In consecutive adult nonsmokers with suspected OSA, FENO was measured immediately before and after polysomnographic studies, and within 1-3 months following continuous positive airway pressure (CPAP) therapy. Measurement and Results: FENO levels were increased in the 75 patients with OSA compared to the 29 controls, both before sleep (13.4 ± 6.5 ppb vs. 6.5 ± 3.5; p Paschke K; Laskowski D; Dweik RA. Long-term continuous positive airway pressure therapy normalizes high exhaled nitric oxide levels in obstructive sleep apnea. J Clin Sleep Med 2013;9(6):529-535. PMID:23772184

  2. Exhaled breath analysis using electronic nose in cystic fibrosis and primary ciliary dyskinesia patients with chronic pulmonary infections

    Joensen, Odin; Paff, Tamara; Haarman, Eric G;

    2014-01-01

    The current diagnostic work-up and monitoring of pulmonary infections may be perceived as invasive, is time consuming and expensive. In this explorative study, we investigated whether or not a non-invasive exhaled breath analysis using an electronic nose would discriminate between cystic fibrosis...... (CF) and primary ciliary dyskinesia (PCD) with or without various well characterized chronic pulmonary infections. We recruited 64 patients with CF and 21 with PCD based on known chronic infection status. 21 healthy volunteers served as controls. An electronic nose was employed to analyze exhaled......, this method significantly discriminates CF patients suffering from a chronic pulmonary P. aeruginosa (PA) infection from CF patients without a chronic pulmonary infection. Further studies are needed for verification and to investigate the role of electronic nose technology in the very early diagnostic...

  3. Effect of age and eosinophil number on fractional exhaled nitric oxide level in non-asthmatic children in shanghai.

    Wei Liu; Jizhi Chu; Li Sun; Zhiqin Shen; Yan Liu; Qing Peng; Xiwen Gao

    2014-01-01

    This study aimed to identify the relationship between fractional exhaled nitric oxide (FeNO) level and potential factors in non-asthmatic children from Shanghai, China. From March to April 2012, the school-aged children fulfilling the inclusion criteria were recruited. The FeNO levels of non-asthmatic children were detected by the Nano Coulomb nitric oxide analyzer. Questionnaires were recorded, including personal data, family illness history and daily habits. In addition, not only the number...

  4. Exhaled Nitric Oxide Fraction as an Add-On to ACQ-7 for Not Well Controlled Asthma Detection

    Plaza, Vicente; Ramos-Barbón, David; Muñoz, Ana María; Fortuna, Ana María; Crespo, Astrid; Murio, Cristina; Palomino, Rosa; ,

    2013-01-01

    Background The measurement of fractional nitric oxide concentration in exhaled breath (FeNO), a noninvasive indicator of airway inflammation, remains controversial as a tool to assess asthma control. Guidelines currently limit asthma control assessment to symptom and spirometry based appraisals such as the Asthma Control Questionnaire-7 (ACQ-7). We aimed at determining whether adding FeNO to ACQ-7 improves current asthma clinical control assessment, through enhanced detection of not well cont...

  5. Numerical simulation of {sup 222}RN exhalation from phosphogypsum building blocks and accumulation inside a closed chamber

    Rabi Junior, Jose A. [Sao Paulo Univ., Pirassununga, SP (Brazil). Faculdade de Zootecnia e Engenharia de Alimentos]. E-mail: jrabi@fzea.usp.br; Silva, Nivaldo C. da [Pontificia Univ. Catolica de Minas Gerais, Pocos de Caldas, MG (Brazil)]|[Comissao Nacional de Energia Nuclear (CNEN), Pocos de Caldas, MG (Brazil). Laboratorio]. E-mail: ncsilva@pucpcaldas.br; ncsilva@cnen.gov.br

    2005-07-01

    Zero-order models for {sup 222}Rn exhalation from phosphogypsum-bearing building materials and its transient indoor accumulation assume uniform distribution inside the enclosure. Conversely, this paper numerically simulates a transient two-dimensional {sup 222}Rn accumulation in a test chamber that contains a phosphogypsum board at one wall. Results show that above hypothesis might be oversimplified when spatial dependence is considered. (author)

  6. No effect of omeprazole on pH of exhaled breath condensate in cough associated with gastro-oesophageal reflux

    Torrego, Alfonso; Cimbollek, Stefan; Hew, Mark; Chung, Kian Fan

    2005-01-01

    Background Endogenous airway acidification evaluated as pH in exhaled breath condensate (EBC) has been described in patients with chronic cough. Proton pump inhibitors improve gastro-oesophageal reflux (GOR)-associated cough. Methods We examined pH levels in EBC and capsaicin cough response in 13 patients with chronic cough (mean age 41 years, SD 9) associated with GOR before and after omeprazole treatment (40 mg/day for 14 days) and its relationship with clinical response. Results Omeprazole...

  7. Near-IR laser-based spectrophotometer for comparative analysis of isotope content of CO2 in exhale air samples

    We present a laser spectrophotometer aimed at high-accuracy comparative analysis of content of 12CO2 and 13CO2 isotope modifications in the exhale air samples and based on a tunable near-IR diode laser (2.05 μm). The two-channel optical scheme of the spectrophotometer and the special digital system for its control are described. An algorithm of spectral data processing aimed at determining the difference in the isotope composition of gas mixtures is proposed. A few spectral regions (near 4880 cm-1) are determined to be optimal for analysis of relative content of 12CO2 and 13CO2 in the exhale air. The use of the proposed spectrophotometer scheme and the developed algorithm makes the results of the analysis less susceptible to the influence of the interference in optical elements, to the absorption in the open atmosphere, to the slow drift of the laser pulse envelope, and to the offset of optical channels. The sensitivity of the comparative analysis of the isotope content of CO2 in exhale air samples, achieved using the proposed scheme, is estimated to be nearly 0.1‰.

  8. Exhaled breath analysis in childhood rheumatic disorders--a longitudinal study.

    Hendel, N; Akmatov, M K; Hamel, J; Vogelberg, C; Pessler, F

    2016-06-01

    We aimed to evaluate the fraction of exhaled nitric oxide (FENO50) and deaerated exhaled breath condensate pH (dEBCpH) as non-invasive markers of subclinical airway inflammation in pediatric patients with rheumatologic disorders. We determined FENO50 and dEBCpH in a prospective study spanning at least 12 months, comprising 85 pediatric patients with rheumatologic disorders, including juvenile idiopathic arthritis (JIA, n  =  63), chronic recurrent multifocal osteomyelitis (CRMO, n  =  6), systemic lupus erythematosus (SLE, n  =  3), juvenile dermatomyositis (JDM, n  =  1) and other rheumatic disorders (n  =  12). dEBCpH was determined once in a group of children without evidence of rheumatologic or pulmonary disease (controls, n  =  90). Findings were correlated with results of pulmonary function tests. Atopic sensitization was assessed by RAST or skin prick test in 76 patients. Atopic sensitization was detected in 34% (26/76) of patients. Neither FENO50 nor dEBCpH correlated with disease activity, but intermediately (20-35 ppb) or highly elevated (>35 ppb) levels were observed at least once in 26 patients (31%), 19 of whom had atopic sensitization. Median dEBCpH did not differ between cases and controls (8.05 versus 8.02; p  =  0.48). Median dEBCpH decreased slightly over the study period (p  =  0.02), whereas FENO50 values did not change significantly (p  =  0.89). There were several patients with significantly abnormal dEBCpH values that could not be readily explained by diagnosis, higher disease activity, medications, or atopic sensitization. Thus, there were no consistent abnormalities in FENO50 or dEBCpH in this cohort of Caucasian patients with relatively stable rheumatologic disorders, but there were some patients with abnormal values of unknown significance. PMID:27093271

  9. Short-term effects of electronic and tobacco cigarettes on exhaled nitric oxide

    The objective of this study was to compare the short-term respiratory effects due to the inhalation of electronic and conventional tobacco cigarette-generated mainstream aerosols through the measurement of the exhaled nitric oxide (eNO). To this purpose, twenty-five smokers were asked to smoke a conventional cigarette and to vape an electronic cigarette (with and without nicotine), and an electronic cigarette without liquid (control session). Electronic and tobacco cigarette mainstream aerosols were characterized in terms of total particle number concentrations and size distributions. On the basis of the measured total particle number concentrations and size distributions, the average particle doses deposited in alveolar and tracheobronchial regions of the lungs for a single 2-s puff were also estimated considering a subject performing resting (sitting) activity. Total particle number concentrations in the mainstream resulted equal to 3.5 ± 0.4 × 109, 5.1 ± 0.1 × 109, and 3.1 ± 0.6 × 109 part. cm−3 for electronic cigarettes without nicotine, with nicotine, and for conventional cigarettes, respectively. The corresponding alveolar doses for a resting subject were estimated equal to 3.8 × 1010, 5.2 × 1010 and 2.3 × 1010 particles. The mean eNO variations measured after each smoking/vaping session were equal to 3.2 ppb, 2.7 ppb and 2.8 ppb for electronic cigarettes without nicotine, with nicotine, and for conventional cigarettes, respectively; whereas, negligible eNO changes were measured in the control session. Statistical tests performed on eNO data showed statistically significant differences between smoking/vaping sessions and the control session, thus confirming a similar effect on human airways whatever the cigarette smoked/vaped, the nicotine content, and the particle dose received. - Highlights: • Electronic cigarettes (with and without nicotine) mainstream aerosols were analyzed; • Particle number concentrations and size distributions were

  10. Short-term effects of electronic and tobacco cigarettes on exhaled nitric oxide

    Marini, Sara, E-mail: s.marini@unicas.it [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino (Italy); Buonanno, Giorgio [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino (Italy); Queensland University of Technology, Brisbane (Australia); Stabile, Luca; Ficco, Giorgio [Department of Civil and Mechanical Engineering, University of Cassino and Southern Lazio, Cassino (Italy)

    2014-07-01

    The objective of this study was to compare the short-term respiratory effects due to the inhalation of electronic and conventional tobacco cigarette-generated mainstream aerosols through the measurement of the exhaled nitric oxide (eNO). To this purpose, twenty-five smokers were asked to smoke a conventional cigarette and to vape an electronic cigarette (with and without nicotine), and an electronic cigarette without liquid (control session). Electronic and tobacco cigarette mainstream aerosols were characterized in terms of total particle number concentrations and size distributions. On the basis of the measured total particle number concentrations and size distributions, the average particle doses deposited in alveolar and tracheobronchial regions of the lungs for a single 2-s puff were also estimated considering a subject performing resting (sitting) activity. Total particle number concentrations in the mainstream resulted equal to 3.5 ± 0.4 × 10{sup 9}, 5.1 ± 0.1 × 10{sup 9}, and 3.1 ± 0.6 × 10{sup 9} part. cm{sup −3} for electronic cigarettes without nicotine, with nicotine, and for conventional cigarettes, respectively. The corresponding alveolar doses for a resting subject were estimated equal to 3.8 × 10{sup 10}, 5.2 × 10{sup 10} and 2.3 × 10{sup 10} particles. The mean eNO variations measured after each smoking/vaping session were equal to 3.2 ppb, 2.7 ppb and 2.8 ppb for electronic cigarettes without nicotine, with nicotine, and for conventional cigarettes, respectively; whereas, negligible eNO changes were measured in the control session. Statistical tests performed on eNO data showed statistically significant differences between smoking/vaping sessions and the control session, thus confirming a similar effect on human airways whatever the cigarette smoked/vaped, the nicotine content, and the particle dose received. - Highlights: • Electronic cigarettes (with and without nicotine) mainstream aerosols were analyzed; • Particle number

  11. Study of mitochondrial DNA alteration in the exhaled breath condensate of patients affected by obstructive lung diseases.

    Carpagnano, G E; Lacedonia, D; Carone, M; Soccio, P; Cotugno, G; Palmiotti, G A; Scioscia, G; Foschino Barbaro, M P

    2016-01-01

    Mitochondrial DNA (MtDNA) has been studied as an expression of oxidative stress in asthma, COPD, lung cancer and obstructive sleep apnea, but it has been mainly investigated systemically, although the pathogenetic mechanisms begin in the airways and only later progress to systemic circulation. The aim of this study was to investigate the MtDNA alterations in the exhaled breath condensate (EBC) of patients with asthma, COPD and asthma-COPD overlap syndrome (ACOS). In order to analyze better what happens to mitochondria, both locally and systemically, we compared MtDNA/nDNA in blood and EBC of paired patients. Thirteen (13) COPD patients, 14 asthmatics, 23 ACOS (10 according to Spanish guidelines, 13 in line with GINA guidelines) and 12 healthy subjects were enrolled. Patients underwent clinical and functional diagnostic tests as foreseen by the guidelines. They underwent blood and EBC collection. Content of MtDNA and nuclear DNA (nDNA) was measured in the blood cells and EBC of patients by Real Time PCR. The ratio between MtDNA/nDNA was calculated. For the first time we were able to detect MtDNA/nDNA in the EBC. We found higher exhaled MtDNA/nDNA in COPD, asthmatic and ACOS patients respectively compared to healthy subjects (21.9  ±  4.9 versus 6.51  ±  0.21, p  <  0.05; 7.9  ±  2.5 versus 6.51  ±  0.21, p  =  0.06; 18.3  ±  3.4 versus 6.51  ±  0.21, p  <  0.05). The level of exhaled MtDNA/nDNA was positively correlated with the plasmatic one. The levels of MtDNA/nDNA in the EBC, as expression of oxidative stress, are increased in COPD, asthmatic and ACOS patients compared to healthy subjects. These are preliminary results in a small number of well characterized patients that requires confirmation on a larger population. We support new studies directed toward the analysis of exhaled MtDNA/nDNA as a new exhaled non-invasive marker in other inflammatory/oxidative airways diseases. PMID

  12. Comparative analysis of selected exhaled breath biomarkers obtained with two different temperature-controlled devices

    Brüning Thomas

    2009-11-01

    Full Text Available Abstract Background The collection of exhaled breath condensate (EBC is a suitable and non-invasive method for evaluation of airway inflammation. Several studies indicate that the composition of the condensate and the recovery of biomarkers are affected by physical characteristics of the condensing device and collecting circumstances. Additionally, there is an apparent influence of the condensing temperature, and often the level of detection of the assay is a limiting factor. The ECoScreen2 device is a new, partly single-use disposable system designed for studying different lung compartments. Methods EBC samples were collected from 16 healthy non-smokers by using the two commercially available devices ECoScreen2 and ECoScreen at a controlled temperature of -20°C. EBC volume, pH, NOx, LTB4, PGE2, 8-isoprostane and cys-LTs were determined. Results EBC collected with ECoScreen2 was less acidic compared to ECoScreen. ECoScreen2 was superior concerning condensate volume and detection of biomarkers, as more samples were above the detection limit (LTB4 and PGE2 or showed higher concentrations (8-isoprostane. However, NOx was detected only in EBC sampled by ECoScreen. Conclusion ECoScreen2 in combination with mediator specific enzyme immunoassays may be suitable for measurement of different biomarkers. Using this equipment, patterns of markers can be assessed that are likely to reflect the complex pathophysiological processes in inflammatory respiratory disease.

  13. Fraction of exhaled nitric oxide measurements in the diagnoses of asthma in elderly patients

    Godinho Netto, Antonio Carlos Maneira; dos Reis, Túlio Gonçalves; Matheus, Cássia Franco; Aarestrup, Beatriz Julião Vieira; Aarestrup, Fernando Monteiro

    2016-01-01

    Objective To assess the value of fraction of exhaled nitric oxide (FeNO) measurements in the diagnosis of asthma in elderly patients. Methods The clinical symptoms of 202 elderly patients were assessed with the asthma module of the International Study of Asthma and Allergies in Childhood test, which had been modified for the elderly patients, and the diagnostic routine for chronic obstructive pulmonary disease (COPD), which was based on the Global initiative for chronic Obstructive Lung Disease criteria. Of the 202 patients assessed, 43 were subjected to pulmonary function evaluations (spirometry) and FeNO measurements. Results Of the 202 elderly patients, 34 had asthma (23 definite and eleven probable), 20 met COPD criteria, 13 presented with an overlap of asthma and COPD, and 135 did not fit the criteria for obstructive pulmonary disease. Among the 43 elderly patients who were subjected to FeNO measurements, ten showed altered results (23.2%) and 33 had normal results (76.7%). The average value of FeNO in patients with definite and probable asthma undergoing this procedure was 29.2 parts per billion whereas that in nonasthmatic patients was 17.5 parts per billion (P=0.0002). Conclusion We show a clear relationship between FeNO levels and asthma symptoms and previous asthma diagnoses in elderly patients. PMID:27274212

  14. Combined atmospheric oxidant capacity and increased levels of exhaled nitric oxide

    Yang, Changyuan; Li, Huichu; Chen, Renjie; Xu, Wenxi; Wang, Cuicui; Tse, Lap Ah; Zhao, Zhuohui; Kan, Haidong

    2016-07-01

    Nitrogen dioxide and ozone are two interrelated oxidative pollutants in the atmosphere. Few studies have evaluated the health effects of combined oxidant capacity (O x ). We investigated the short-term effects of O x on fractional exhaled nitric oxide (FeNO), a well-established biomarker for airway inflammation, in a group of chronic obstructive pulmonary disease patients. Real-time concentrations of O x were obtained by calculating directly the sum of nitrogen dioxide and ozone. Linear mixed-effect models were applied to explore the acute effects of O x on FeNO levels. Short-term exposure to Ox was significantly associated with elevated FeNO. This effect was strongest in the first 24 h after exposure, and was robust to the adjustment of PM2.5. A 10 μg m‑3 increase in 24 h average concentrations of O x was associated with 4.28% (95% confidence interval: 1.19%, 7.37%) increase in FeNO. The effect estimates were statistically significant only among males, elders, and those with body mass index ≥24 kg m‑2, a comorbidity, higher educational attainment, or moderate airflow limitation. This analysis demonstrated an independent effect of O x on respiratory inflammation, and suggested that a single metric O x might serve as a preferable indicator of atmospheric oxidative capacity in further air pollution epidemiological studies.

  15. Fractional exhaled nitric oxide: comparison between portable devices and correlation with sputum eosinophils.

    Yune, Sehyo; Lee, Jin Young; Choi, Dong Chull; Lee, Byung Jae

    2015-07-01

    This study was performed to compare the 2 different portable devices measuring fractional exhaled nitric oxide (FeNO) and to see the correlation between FeNO and induced sputum eosinophil count (ISE). Forty consecutive subjects clinically suspected to have asthma underwent FeNO measurement by NIOX-MINO® and NObreath® concurrently. All also had induced sputum analysis, methacholine provocation test or bronchodilator response test, and spin prick test. Agreement between the 2 devices was evaluated. The correlation between FeNO and ISE was assessed, as well as the cut-off level of FeNO to identify ISE ≥3%. The intraclass correlation coefficient (ICC) between FeNO levels measured by NIOX-MINO® (FeNO(NIOX-MINO)) and NObreath® (FeNO(NObreath)) was 0.972 with 95% confidence interval of 0.948-0.985. The 95% limits of agreement were -28.9 to 19.9 ppb. The correlation coefficient between ISE and FeNO(NIOX-MINO) was 0.733 (Plevel and its correlation with ISE. The NIOX-MINO ® and NObreath® agree with each other to a high degree. Both devices showed close correlation with ISE with similar cut-off value in identifying ISE ≥3%. PMID:25749783

  16. Exhaled nitric oxide predicts exercise-induced bronchoconstriction in asthmatic school children

    Buchvald, Frederik; Hermansen, Mette N; Nielsen, Kim G;

    2005-01-01

    BACKGROUND: Exercise-induced bronchoconstriction (EIB) is of particular importance in children with asthma. It is an important measure of asthma control and should be monitored by exercise testing. However, exercise testing puts a large demand on health-care resources and is therefore not widely ...... inhaled corticosteroid treatment. CONCLUSION: Measurement of FeNO is a simple, and time- and resource-efficient tool that may be used to screen for EIB testing and therefore optimizes the resources for exercise testing in pediatric asthma monitoring.......BACKGROUND: Exercise-induced bronchoconstriction (EIB) is of particular importance in children with asthma. It is an important measure of asthma control and should be monitored by exercise testing. However, exercise testing puts a large demand on health-care resources and is therefore not widely...... used in routine monitoring of pediatric asthma control. The fractional concentration of exhaled nitric oxide (FeNO) also reflects uncontrolled asthma. We hypothesized that FeNO may be used for prescreening of asthmatic children to exclude those with good asthma control unlikely to have EIB, thereby...

  17. A mini review of dolphin carbohydrate metabolism and suggestions for future research using exhaled air

    Sam eRidgway

    2013-12-01

    Full Text Available In the 1960s, I explored some aspects of carbohydrate metabolism in healthy bottlenose dolphins (Tursiops truncatus. Their physiological picture resembled what had been described for hyperthyroid diabetics. Dolphins have elevated thyroid hormone turnover, and fasting dolphins maintain a relatively high level of plasma glucose. After dolphins ingest glucose, plasma levels remain high for many hours. Interestingly, plasma glucose must exceed 300 mg/dL (about twice as high as the human threshold before glucose appears in urine. Due to their diabetes-like states, trainability, and unique natural respiratory anatomy and physiology, dolphins may offer useful clues to metabolites in the breath that may be used to non-invasively monitor diabetes in humans. Dolphins take very rapid and deep breaths that are four or five times as deep as humans and other terrestrial mammals, making them ideal for physiological assessment using non-invasive exhaled air. Avenues for successfully identifying breath-based markers for metabolic disease and physiology in dolphins can be done with both modern technology and the evolutionarily advantageous canine nose. This review summarizes aspects of dolphin metabolism previously learned and offers new directions for diabetes research that may benefit both dolphin and human health.

  18. Measurement of endogenous acetone and isoprene in exhaled breath during sleep

    This explorative study aims at characterizing the breath behavior of two prototypic volatile organic compounds, acetone and isoprene, during normal human sleep and to possibly relate changes in the respective concentration time courses to the underlying sleep architecture. For this purpose, six normal healthy volunteers (two females, four males, age 20–29 years) were monitored over two consecutive nights (the first one being an adaption night) by combining real-time proton-transfer-reaction mass spectrometry measurements from end-tidal exhalation segments with laboratory-based polysomnographic data. Breath acetone concentrations increased overnight in all measurements, with an average relative change by a factor of up to 4 (median 2.5). Nighttime concentration maxima were usually recorded 2–3 h before lights on. For breath isoprene, a nocturnal increase in baseline concentrations of about 74% was observed, with individual changes ranging from 36–110%. Isoprene profiles exhibited pronounced concentration peaks, which were highly specific for leg movements as scored by tibial electromyography. Furthermore, relative to a linear trend, baseline isoprene concentrations decreased during the transition from the NREM to the REM phase of a complete sleep cycle. (paper)

  19. Solid thoron source preparation in a porous mineral matrix

    Thoron and progeny are decay products of 232Th with a great impact on human health. The release of thoron gas from the mining and milling of thorite, monazite and other major thorium ores has been recognised as a potential radiological health hazard. For precise measurements, calibration is a very important factor. This paper describes a cheap and easy way of producing a stable thoron source made of thorium nitrate packed in a porous clay mineral matrix used as 220Rn generator. The source should have a small spherical shape and be fired at 600 deg. C; this will lead to a great pore volume, necessary for the thoron gas. High importance should be given to the water uptake. The exhalation power of 220Rn was measured using a Lucas scintillation cell. Experimental efficiency values obtained ranged between 0.16 and 1.44%. (authors)

  20. Meteorological influences on atmospheric radioactivity and its effects on the electrical environment

    The 222Rn content of soil gas is influenced by meteorological parameters and especially by wind speed. For 220Rn the effects are less pronounced. The exhalation of 220Rn is dependent on precipitation and atmospheric turbulence. From horizontal measurements of radioactivity in the air, the most representative values are obtained under unstable, near-neutral, and light stable stratifications. The concentration of natural radioactivity at a point in the atmospheric surface layer can be expressed in terms of atmospheric stability if the horizontal distributions are fairly homogeneous. For longtime variations of radioactivity in the air, the precipitation and groundwater conditions are of prime concern. But for the rapid fluctuations the turbulent processes give the main contribution to the variations

  1. Development of a predictive methodology for identifying high radon exhalation potential areas; Mise au point d'une methodologie predictive des zones a fort potentiel d'exhalation du radon

    Ielsch, G

    2001-07-01

    Radon 222 is a radioactive natural gas originating from the decay of radium 226 which itself originates from the decay of uranium 23 8 naturally present in rocks and soil. Inhalation of radon gas and its decay products is a potential health risk for man. Radon can accumulate in confined environments such as buildings, and is responsible for one third of the total radiological exposure of the general public to radiation. The problem of how to manage this risk then arises. The main difficulty encountered is due to the large variability of exposure to radon across the country. A prediction needs to be made of areas with the highest density of buildings with high radon levels. Exposure to radon varies depending on the degree of confinement of the habitat, the lifestyle of the occupants and particularly emission of radon from the surface of the soil on which the building is built. The purpose of this thesis is to elaborate a methodology for determining areas presenting a high potential for radon exhalation at the surface of the soil. The methodology adopted is based on quantification of radon exhalation at the surface, starting from a precise characterization of the main local geological and pedological parameters that control the radon source and its transport to the ground/atmosphere interface. The methodology proposed is innovative in that it combines a cartographic analysis, parameters integrated into a Geographic Information system, and a simplified model for vertical transport of radon by diffusion through pores in the soil. This methodology has been validated on two typical areas, in different geological contexts, and gives forecasts that generally agree with field observations. This makes it possible to identify areas with a high exhalation potential within a range of a few square kilometers. (author)

  2. Exhaled nitric oxide collected with two different mouthpieces: a study in asthmatic patients

    Leme A.S.

    2002-01-01

    Full Text Available Techniques for collecting exhaled nitric oxide (ENO recommend the use of antibacterial filters of 0.3 µm. The aim of the present study was to compare the measurements of ENO obtained with two different filtering devices. Air samples from 17 asthmatic and 17 non-asthmatic subjects were collected by a recommended off-line technique using two different mouthpieces: 1 the Sievers disposable tool (A under a breathing pressure of 18 cmH2O, and 2 a mouthpiece containing a HEPA filter (B under a breathing pressure of 12 cmH2O. The nitric oxide samples were collected into an impermeable reservoir bag. Values for ENO were compared using two-way repeated measures ANOVA followed by the Tukey test. Agreement was assessed by Bland-Altman analysis. ENO values obtained with mouthpieces A and B were comparable for asthmatic (mean ± SEM, 42.9 ± 6.9 vs 43.3 ± 6.6 ppb and non-asthmatic (13.3 ± 1.3 vs 13.7 ± 1.1 ppb subjects. There was a significant difference in ENO between asthmatics and non-asthmatics using either mouthpiece A (P<0.001 or B (P<0.001. There was a positive correlation between mouthpiece A and mouthpiece B for both groups. The Bland-Altman limits of agreement were considered to be acceptable. Mouthpiece B was less expensive than A, and these data show that it can be used without compromising the result. Our data confirm reports of higher ENO values in the presence of airway inflammation.

  3. Effect of drinking Arabian Qahwa on fractional exhaled nitric oxide levels in healthy nonsmoking Saudi adults

    Syed Shahid Habib

    2012-01-01

    Full Text Available Objectives: Fractional exhaled nitric oxide (FENO is an emerging marker of inflammation in respiratory diseases. However, it is affected by a number of confounding factors. We aimed to study the effect of drinking Arabian Qahwa on FENO in non-smoking Saudi healthy adults. Methods: We recruited 12 nonsmoker healthy male adults aged 36.6 ± 2.7 (21-50 years. All subjects were free from acute respiratory infections or allergies and had normal ventilatory functions and serum IgE levels. At 8 am in the morning, their baseline values of FENO were recorded. They had not taken tea or coffee in the morning and had taken similar light breakfast. They were given three cups of Arabian Qahwa to drink and then after every 30 minutes, serial levels of FENO were recorded. Results: Average FENO levels at baseline were 28.73 ± 9.33 (mean ± SD parts per billion (ppb. The mean FENO levels started to decrease significantly after 30 minutes of drinking Arabian Qahwa (P=0.002. This decrease in FENO level was further observed till two hours after Qahwa drinking and then it started to increase in next 90 minutes but still was significantly lower than the baseline (P=0.002. The mean FENO level recorded after 4 hours was 27.22 ± 10.22 (P=0.039. Conclusions: FENO levels were significantly lowered by intake of Arabian Qahwa and this effect remains for about 4 hours. Therefore, history of recent Qahwa intake and abstinence is essential before performance of FENO and its interpretation.

  4. Exhaled nitric oxide and airway hyperresponsiveness in workers: a preliminary study in lifeguards

    Massin Nicole

    2009-12-01

    Full Text Available Abstract Background Airway inflammation and airway hyperresponsiveness (AHR are two characteristic features of asthma. Fractional exhaled nitric oxide (FENO has shown good correlation with AHR in asthmatics. Less information is available about FENO as a marker of inflammation from work exposures. We thus examined the relation between FENO and AHR in lifeguards undergoing exposure to chloramines in indoor pools. Methods 39 lifeguards at six indoor pools were given a respiratory health questionnaire, FENO measurements, spirometry, and a methacholine bronchial challenge (MBC test. Subjects were labeled MBC+ if the forced expiratory volume (FEV1 fell by 20% or more. The normalized linear dose-response slope (NDRS was calculated as the percentage fall in FEV1 at the last dose divided by the total dose given. The relation between MBC and FENO was assessed using logistic regression adjusting on confounding factors. The association between NDRS and log-transformed values of FENO was tested in a multiple linear regression model. Results The prevalence of lifeguards MBC+ was 37.5%. In reactors, the median FENO was 18.9 ppb (90% of the predicted value vs. 12.5 ppb (73% predicted in non-reactors. FENO values ≥ 60% of predicted values were 80% sensitive and 42% specific to identify subjects MBC+. In the logistic regression model no other factor had an effect on MBC after adjusting for FENO. In the linear regression model, NDRS was significantly predicted by log FENO. Conclusions In lifeguards working in indoor swimming pools, elevated FENO levels are associated with increased airway responsiveness.

  5. Coarse Fraction Particle Matter and Exhaled Nitric Oxide in Non-Asthmatic Children

    Carlsen, Hanne Krage; Boman, Peter; Björ, Bodil; Olin, Anna-Carin; Forsberg, Bertil

    2016-01-01

    Coarse particle matter, PMcoarse, is associated with increased respiratory morbidity and mortality. The aim of this study was to investigate the association between short-term changes in PMcoarse and sub-clininal airway inflammation in children. Healthy children aged 11 years from two northern Swedish elementary schools underwent fraction of exhaled nitrogen oxide (FENO) measurements to determine levels of airway inflammation twice weekly during the study period from 11 April–6 June 2011. Daily exposure to PMcoarse, PM2.5, NO2, NOx, NO and O3 and birch pollen was estimated. Multiple linear regression was used. Personal covariates were included as fixed effects and subjects were included as a random effect. In total, 95 children participated in the study, and in all 493 FENO measurements were made. The mean level of PMcoarse was 16.1 μg/m3 (range 4.1–42.3), and that of O3 was 75.0 μg/m3 (range: 51.3–106.3). That of NO2 was 17.0 μg/m3 (range: 4.7–31.3), NOx was 82.1 μg/m3 (range: 13.3–165.3), and NO was 65 μg/m3 (range: 8.7–138.4) during the study period. In multi-pollutant models an interquartile range increase in 24 h PMcoarse was associated with increases in FENO by between 6.9 ppb (95% confidence interval 0.0–14) and 7.3 ppb (95% confidence interval 0.4–14.9). PMcoarse was associated with an increase in FENO, indicating sub-clinical airway inflammation in healthy children. PMID:27338437

  6. Methodological implications in pH standardization of exhaled breath condensate.

    Hoffmeyer, F; Berresheim, H; Beine, A; Sucker, K; Brüning, T; Bünger, J

    2015-09-01

    The variable amount of dissolved carbon dioxide is one of the main confounding factors of exhaled breath condensate (EBC) pH measurements. There have been many attempts at identifying the optimal approach to displace CO2 as a way to gain reproducible and valid pH values in EBC samples. The aim of the present study was to assess the correlation of pH and pCO2 in untreated, neat EBC samples and, after deaeration, to reevaluate the standardization of CO2 as a means to obtain valid pH values. A further aim was to evaluate the impact of deaeration on the acid-base balance in EBC samples. EBC was collected from seven female and 31 male subjects. The pH and pCO2 values immediately determined in untreated, neat EBC samples were strongly correlated (rp = -0.723, p argon (rs = 0.264, p = 0.109). Based on a regression function for the pH/pCO2 relationship, the calculated pH at a pCO2 of 5.33 kPa was 6.07 (IQR 5.99, 6.20). No significant difference was observed between the pH measured in neat EBC samples and those calculated after deaeration with regression function and measured neat pCO2. Our data suggest that pCO2 is the most important confounder of pH measurement in EBC samples and, when adjusting for pCO2, the acid-base balance of EBC samples is not significantly influenced by the process of deaeration. Furthermore, measurement with a blood-gas analyzer and standardization of pH for pCO2 allows sensitive assaying of EBC samples. Therefore, this method provides a basis for detection of even small changes in airway pH due to inhalative exposure or respiratory disease. PMID:25972098

  7. Importance of fractional exhaled nitric oxide in diagnosis of bronchiectasis accompanied with bronchial asthma

    Chen, Feng-Jia; Liao, Huai; Huang, Xin-Yan

    2016-01-01

    Background Fractional exhaled nitric oxide (FeNO) measurement is a simple, rapid, highly reproducible, and noninvasive method of airway inflammation assessment. Therefore, FeNO is extensively used for the diagnosis and management of asthma. The feasibility of using FeNO as an alternative to conventional pulmonary function test to differentiate patients with bronchiectasis (BE) and bronchial asthma from those with BE only remains unclear. Methods From February 2013 to February 2015, 99 patients diagnosed with BE through high-resolution computed tomography (HRCT) were subjected to FeNO measurement, bronchial challenge test (BCT), or bronchodilator test. Bronchial hyperreactivity and/or reversible airway obstruction was used to define asthma. The receiver operating characteristic (ROC) curves were obtained to elucidate the clinical functions of FeNO in the diagnosis of asthmatic patients with BE, and the optimal operating point was also determined. Results Of 99 patients with BE, 20 patients presented asthma, and 12 of these patients received regular treatment, which were given with budesonide (200 µg, bid) for 12 weeks to evaluate changes in the concentration and assess the role of FeNO in the treatment. The area under the ROC curve was estimated as 0.832 for FeNO. Results also revealed a cut off value of >22.5 part per billion (ppb) FeNO for differentiating asthmatic from non-asthmatic (sensitivity, 90.0%; specificity, 62.5%) patients with BE. FeNO and forced expiratory volume for 1 second significantly improved after the treatment. Conclusions Clinical FeNO measurement is a simple, noninvasive, and rapid method used to differentiate asthmatic from nonasthmatic patients with BE. This technique exhibits potential for asthma management.

  8. Adaptive tolerance in mice upon subchronic exposure to chloroform: Increased exhalation and target tissue regeneration

    The aims of the present study were to characterize the subchronic toxicity of chloroform by measuring tissue injury, repair, and distribution of chloroform and to assess the reasons for the development of tolerance to subchronic chloroform toxicity. Male Swiss Webster (SW) mice were given three dose levels of chloroform (150, 225, and 300 mg/kg/day) by gavage in aqueous vehicle for 30 days. Liver and kidney injury were measured by plasma ALT and BUN, respectively, and by histopathology. Tissue regeneration was assessed by 3H-thymidine incorporation into hepato- and nephro-nuclear DNA and by proliferating cell nuclear antigen staining. In addition, GSH and CYP2E1 in liver and kidney were assessed at selected time points. The levels of chloroform were measured in blood, liver, and kidney during the dosing regimen (1, 7, 14, and 30 days). Kidney injury was evident after 1 day with all three doses and sustained until 7 days followed by complete recovery. Mild to moderate liver injury was observed from 1 to 14 days with all three dose levels followed by gradual decrease. Significantly higher regenerative response was evident in liver and kidney at 7 days, but the response was robust in kidney, preventing progression of injury beyond first week of exposure. While the kidney regeneration reached basal levels by 21 days, moderate liver regeneration with two higher doses sustained through the end of the dosing regimen and 3 days after that. Following repeated exposure for 7, 14, and 30 days, the blood and tissue levels of chloroform were substantially lower with all three dose levels compared to the levels observed with single exposure. Increased exhalation of 14C-chloroform after repeated exposures explains the decreased chloroform levels in circulation and tissues. These results suggest that toxicokinetics and toxicodynamics (tissue regeneration) contribute to the tolerance observed in SW mice to subchronic chloroform toxicity. Neither bioactivation nor detoxification

  9. Possible Impact of Salivary Influence on Cytokine Analysis in Exhaled Breath Condensate

    T. Ichikawa

    2007-01-01

    Full Text Available Background: Exhaled breath condensate (EBC is thought to contain substances of the lower airway epithelial lining fluid (ELF aerosolized by turbulent flow. However, contamination by saliva may affect the EBC when collected orally.Objective: The purpose of this study was to compare the cytokine expression levels in EBC with those in saliva, and to clarify the influence of saliva on cytokine measurements of EBC.Methods: EBC and saliva samples were obtained from 10 adult subjects with stable asthma. To estimate differences in the contents of substances between EBC and saliva, the total protein concentration of each sample was measured. Further, we also measured the total protein concentration of ELF obtained from another patient group with suspected lung cancer using a micro sampling probe during bronchoscopic examination and roughly estimated the dilution of EBC by comparing the total protein concentration of EBC and ELF from those two patient groups. The cytokine expression levels of EBC and saliva from asthmatic group were assessed by a cytokine protein array.Results: The mean total protein concentrations in EBC, saliva and ELF were 4.6 μg/ml, 2,398 μg/ml and 14,111 μg/ml, respectively. The dilution of EBC could be estimated as 1:3000. Forty cytokines were analyzed by a cytokine protein array and each cytokine expression level of EBC was found to be different from that of saliva. Corrected by the total protein concentration, all cytokine expression levels of EBC were significantly higher than those of saliva.Conclusion: These results suggest that the salivary influence on the cytokine assessment in EBC may be negligible.

  10. Coarse Fraction Particle Matter and Exhaled Nitric Oxide in Non-Asthmatic Children

    Hanne Krage Carlsen

    2016-06-01

    Full Text Available Coarse particle matter, PMcoarse, is associated with increased respiratory morbidity and mortality. The aim of this study was to investigate the association between short-term changes in PMcoarse and sub-clininal airway inflammation in children. Healthy children aged 11 years from two northern Swedish elementary schools underwent fraction of exhaled nitrogen oxide (FENO measurements to determine levels of airway inflammation twice weekly during the study period from 11 April–6 June 2011. Daily exposure to PMcoarse, PM2.5, NO2, NOx, NO and O3 and birch pollen was estimated. Multiple linear regression was used. Personal covariates were included as fixed effects and subjects were included as a random effect. In total, 95 children participated in the study, and in all 493 FENO measurements were made. The mean level of PMcoarse was 16.1 μg/m3 (range 4.1–42.3, and that of O3 was 75.0 μg/m3 (range: 51.3–106.3. That of NO2 was 17.0 μg/m3 (range: 4.7–31.3, NOx was 82.1 μg/m3 (range: 13.3–165.3, and NO was 65 μg/m3 (range: 8.7–138.4 during the study period. In multi-pollutant models an interquartile range increase in 24 h PMcoarse was associated with increases in FENO by between 6.9 ppb (95% confidence interval 0.0–14 and 7.3 ppb (95% confidence interval 0.4–14.9. PMcoarse was associated with an increase in FENO, indicating sub-clinical airway inflammation in healthy children.

  11. Coarse Fraction Particle Matter and Exhaled Nitric Oxide in Non-Asthmatic Children.

    Carlsen, Hanne Krage; Boman, Peter; Björ, Bodil; Olin, Anna-Carin; Forsberg, Bertil

    2016-01-01

    Coarse particle matter, PMcoarse, is associated with increased respiratory morbidity and mortality. The aim of this study was to investigate the association between short-term changes in PMcoarse and sub-clininal airway inflammation in children. Healthy children aged 11 years from two northern Swedish elementary schools underwent fraction of exhaled nitrogen oxide (FENO) measurements to determine levels of airway inflammation twice weekly during the study period from 11 April-6 June 2011. Daily exposure to PMcoarse, PM2.5, NO₂, NOx, NO and O₃ and birch pollen was estimated. Multiple linear regression was used. Personal covariates were included as fixed effects and subjects were included as a random effect. In total, 95 children participated in the study, and in all 493 FENO measurements were made. The mean level of PMcoarse was 16.1 μg/m³ (range 4.1-42.3), and that of O₃ was 75.0 μg/m³ (range: 51.3-106.3). That of NO₂ was 17.0 μg/m³ (range: 4.7-31.3), NOx was 82.1 μg/m³ (range: 13.3-165.3), and NO was 65 μg/m³ (range: 8.7-138.4) during the study period. In multi-pollutant models an interquartile range increase in 24 h PMcoarse was associated with increases in FENO by between 6.9 ppb (95% confidence interval 0.0-14) and 7.3 ppb (95% confidence interval 0.4-14.9). PMcoarse was associated with an increase in FENO, indicating sub-clinical airway inflammation in healthy children. PMID:27338437

  12. An acetone bio-sniffer (gas phase biosensor) enabling assessment of lipid metabolism from exhaled breath.

    Ye, Ming; Chien, Po-Jen; Toma, Koji; Arakawa, Takahiro; Mitsubayashi, Kohji

    2015-11-15

    Several volatile organic compounds (VOCs) are released from human breath or skin. Like chemical substances in blood or urine, some of these vapors can provide valuable information regarding the state of the human body. A highly sensitive acetone biochemical gas sensor (bio-sniffer) was developed and used to measure exhaled breath acetone concentration, and assess lipid metabolism based on breath acetone analysis. A fiber-optic biochemical gas sensing system was constructed by attaching a flow-cell with nicotinamide adenine dinucleotide (NADH)-dependent secondary alcohol dehydrogenase (S-ADH) immobilized membrane onto a fiber-optic NADH measurement system. The NADH measurement system utilizes an ultraviolet-light emitting diode with peak emission of 335 nm as an excitation light source. NADH is consumed by the enzymatic reaction of S-ADH, and the consumption is proportional to the concentration of acetone vapor. Phosphate buffer which contained NADH was circulated into the flow-cell to rinse products and the excessive substrates from the optode. The change of fluorescent emitted from NADH is analyzed by the PMT. Hence, fluorescence intensity decreased as the acetone concentration increased. The relationship between fluorescence intensity and acetone concentration was identified from 20 ppb to 5300 ppb. This interval included the concentration of acetone vapor in the breath of healthy people and those suffering from disorders of carbohydrate metabolism. Finally, the acetone bio-sniffer was used to measure breath acetone during an exercise stress test on an ergometer after a period of fasting. The concentration of acetone in breath was shown to significantly increase after exercise. This biosensor allows rapid, highly sensitive and selective measurement of lipid metabolism. PMID:26079672

  13. Normative data for lung function and exhaled nitric oxide in unsedated healthy infants.

    Fuchs, O; Latzin, P; Thamrin, C; Stern, G; Frischknecht, P; Singer, F; Kieninger, E; Proietti, E; Riedel, T; Frey, U

    2011-05-01

    Despite association with lung growth and long-term respiratory morbidity, there is a lack of normative lung function data for unsedated infants conforming to latest European Respiratory Society/American Thoracic Society standards. Lung function was measured using an ultrasonic flow meter in 342 unsedated, healthy, term-born infants at a mean ± sd age of 5.1 ± 0.8 weeks during natural sleep according to the latest standards. Tidal breathing flow-volume loops (TBFVL) and exhaled nitric oxide (eNO) measurements were obtained from 100 regular breaths. We aimed for three acceptable measurements for multiple-breath washout and 5-10 acceptable interruption resistance (R(int)) measurements. Acceptable measurements were obtained in ≤ 285 infants with high variability. Mean values were 7.48 mL·kg⁻¹ (95% limits of agreement 4.95-10.0 mL·kg⁻¹) for tidal volume, 14.3 ppb (2.6-26.1 ppb) for eNO, 23.9 mL·kg⁻¹ (16.0-31.8 mL·kg⁻¹) for functional residual capacity, 6.75 (5.63-7.87) for lung clearance index and 3.78 kPa·s·L⁻¹ (1.14-6.42 kPa·s·L⁻¹) for R(int). In males, TBFVL outcomes were associated with anthropometric parameters and in females, with maternal smoking during pregnancy, maternal asthma and Caesarean section. This large normative data set in unsedated infants offers reference values for future research and particularly for studies where sedation may put infants at risk. Furthermore, it highlights the impact of maternal and environmental risk factors on neonatal lung function. PMID:21109556

  14. Determination of hexavalent chromium in exhaled breath condensate and environmental air among chrome plating workers

    Chromium speciation has attracted attention because of the different toxicity of Cr(III), which is considered relatively non-toxic, and Cr(VI), which can cross cell membranes mainly as a chromate anion and has been classified as a class I human carcinogen. The aims of the present study were to measure soluble Cr(VI) levels in environmental samples, to develop a simple method of quantifying Cr(VI) in exhaled breath condensate (EBC), and to follow the kinetics of EBC Cr(VI) in chrome plating workers. Personal air samples were collected from 10 chrome platers; EBC was collected from the same workers immediately after the work shift on Tuesday and before the work shift on the following Wednesday. Environmental and EBC Cr(VI) levels were determined by means of colorimetry and electrothermal absorption atomic spectrometry, respectively. The method of detecting Cr(VI) in environmental air was based on the extraction of the Cr(VI)-diphenylcarbazide (Cr(VI)-DPC) complex in 1-butanol, whereas EBC Cr(VI) was determined using a solvent extraction of Cr(VI) as an ion pair with tetrabutylammonium ion, and subsequent direct determination of the complex (Cr(VI)-DPC) in EBC. Kinetic data showed that airborne Cr(VI) was reduced by 50% in airway lining fluid sampled at the end of exposure and that there was a further 50% reduction after about 15 h. The persistence of Cr(VI) in EBC supports the use of EBC in assessing target tissue levels of Cr(VI)

  15. Exhaled nitric oxide levels and lung function changes of underground coal miners in Newcastle, Australia

    Liu, X.H.; Salter, A.; Thomas, P.; Leigh, J.; Wang, H. [Tulane University, New Orleans, LA (USA). Dept. of Environmental Health Science

    2010-07-01

    The possibility of exhaled nitric oxide (eNO) in combination with lung function as a marker of airway inflammation produced by coal mining exposure was determined presuming that workers exposed to airborne hazards would possess different concentrations of eNO and decreased lung function indices, relative to control subjects recruited from the same area. The effect of smoking was also considered. A study (exposed) group comprising 186 male subjects (aged 19-58 yr) was recruited from Newcastle coal mining companies with 86 male subjects (aged 20-64 yr) from the same area, but working outside of the coal mining location, serving as controls. The parameters examined were eNO, lung function, and variables derived from an interview-administered questionnaire survey. After adjustment for age, body weight, and smoking status, no significant differences between exposed coal mining workers and controls were found for various lung function parameters. However, the exposed group was shown to have significantly lower concentrations of eNO. In the exposed group, forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and FEV1 (%) predicted were found to be significantly different between nonsmokers and smokers. The concentrations of eNO were not significantly different between smoking and nonsmokers within the exposed group. Data suggest that exposure to airborne hazards in coal mining is not significantly associated with lung function changes but is correlated with decreased eNO concentrations in exposed workers. While underground work duration was not found to be significantly associated with eNO concentrations in coal mining workers in this study, the potential for using eNO as a monitoring marker still exists and further studies are needed to establish its importance.

  16. A Full-Scale Study of Exhaled Droplet Dispersion in the Microenvironment around one and two Persons

    Nielsen, Peter V.; Li, Yuguo; Khalegi, Farzad;

    measurements on the flow in the microenvironment around persons with respect to droplet nuclei (< 5- 10 μm). Measurement of settled particles (droplets > 5-10 μm) on the floor around a manikin (person) will then be shown for different heat releases from the manikin. These results are in good agreement with the...... expectation of a settlement within a “short” distance of 1.5 m, Lidwell and Williams (1961). Experiments with the exhalation of particles from a source manikin close to the other manikin are also performed. The results show that in this case the change in the microenvironment will influence the particle...

  17. An integrative clinical database and diagnostics platform for biomarker identification and analysis in ion mobility spectra of human exhaled air

    Schneider, Till; Hauschild, Anne-Christin; Baumbach, Jörg Ingo;

    2013-01-01

    Over the last decade the evaluation of odors and vapors in human breath has gained more and more attention, particularly in the diagnostics of pulmonary diseases. Ion mobility spectrometry coupled with multi-capillary columns (MCC/IMS), is a well known technology for detecting volatile organic...... compounds (VOCs) in air. It is a comparatively inexpensive, non-invasive, high-throughput method, which is able to handle the moisture that comes with human exhaled air, and allows for characterizing of VOCs in very low concentrations. To identify discriminating compounds as biomarkers, it is necessary to...

  18. pH in exhaled breath condensate and nasal lavage as a biomarker of air pollution-related inflammation in street traffic-controllers and office-workers

    Thamires Marques de Lima

    2013-12-01

    Full Text Available OBJECTIVE: To utilize low-cost and simple methods to assess airway and lung inflammation biomarkers related to air pollution. METHODS: A total of 87 male, non-smoking, healthy subjects working as street traffic-controllers or office-workers were examined to determine carbon monoxide in exhaled breath and to measure the pH in nasal lavage fluid and exhaled breath condensate. Air pollution exposure was measured by particulate matter concentration, and data were obtained from fixed monitoring stations (8-h work intervals per day, during the 5 consecutive days prior to the study. RESULTS: Exhaled carbon monoxide was two-fold greater in traffic-controllers than in office-workers. The mean pH values were 8.12 in exhaled breath condensate and 7.99 in nasal lavage fluid in office-workers; these values were lower in traffic-controllers (7.80 and 7.30, respectively. Both groups presented similar cytokines concentrations in both substrates, however, IL-1β and IL-8 were elevated in nasal lavage fluid compared with exhaled breath condensate. The particulate matter concentration was greater at the workplace of traffic-controllers compared with that of office-workers. CONCLUSION: The pH values of nasal lavage fluid and exhaled breath condensate are important, robust, easy to measure and reproducible biomarkers that can be used to monitor occupational exposure to air pollution. Additionally, traffic-controllers are at an increased risk of airway and lung inflammation during their occupational activities compared with office-workers.

  19. Non-invasive measurements of exhaled NO and CO associated with methacholine responses in mice

    Ameredes Bill T

    2008-05-01

    Full Text Available Abstract Background Nitric oxide (NO and carbon monoxide (CO in exhaled breath are considered obtainable biomarkers of physiologic mechanisms. Therefore, obtaining their measures simply, non-invasively, and repeatedly, is of interest, and was the purpose of the current study. Methods Expired NO (ENO and CO (ECO were measured non-invasively using a gas micro-analyzer on several strains of mice (C57Bl6, IL-10-/-, A/J, MKK3-/-, JNK1-/-, NOS-2-/- and NOS-3-/- with and without allergic airway inflammation (AI induced by ovalbumin systemic sensitization and aerosol challenge, compared using independent-sample t-tests between groups, and repeated measures analysis of variance (ANOVA within groups over time of inflammation induction. ENO and ECO were also measured in C57Bl6 and IL-10-/- mice, ages 8–58 weeks old, the relationship of which was determined by regression analysis. S-methionyl-L-thiocitrulline (SMTC, and tin protoporphyrin (SnPP were used to inhibit neuronal/constitutive NOS-1 and heme-oxygenase, respectively, and alter NO and CO production, respectively, as assessed by paired t-tests. Methacholine-associated airway responses (AR were measured by the enhanced pause method, with comparisons by repeated measures ANOVA and post-hoc testing. Results ENO was significantly elevated in naïve IL-10-/- (9–14 ppb and NOS-2-/- (16 ppb mice as compared to others (average: 5–8 ppb, whereas ECO was significantly higher in naïve A/J, NOS-3-/- (3–4 ppm, and MKK3-/- (4–5 ppm mice, as compared to others (average: 2.5 ppm. As compared to C57Bl6 mice, AR of IL-10-/-, JNK1-/-, NOS-2-/-, and NOS-3-/- mice were decreased, whereas they were greater for A/J and MKK3-/- mice. SMTC significantly decreased ENO by ~30%, but did not change AR in NOS-2-/- mice. SnPP reduced ECO in C57Bl6 and IL-10-/- mice, and increased AR in NOS-2-/- mice. ENO decreased as a function of age in IL-10-/- mice, remaining unchanged in C57Bl6 mice. Conclusion These results are

  20. Impact of food intake on in vivo VOC concentrations in exhaled breath assessed in a caprine animal model.

    Fischer, Sina; Bergmann, Andreas; Steffens, Markus; Trefz, Phillip; Ziller, Mario; Miekisch, Wolfram; Schubert, Jochen S; Köhler, Heike; Reinhold, Petra

    2015-12-01

    Physiological processes within the body may change emitted volatile organic compound (VOC) composition, and may therefore cause confounding biological background variability in breath gas analyses. To evaluate the effect of food intake on VOC concentration patterns in exhaled breath, this study assessed the variability of VOC concentrations due to food intake in a standardized caprine animal model. VOCs in (i) alveolar breath gas samples of nine clinically healthy goats and (ii) room air samples were collected and pre-concentrated before morning feeding and repeatedly after (+60 min, +150 min, +240 min) using needle trap microextraction (NTME). Analysis of VOCs was performed by gas chromatography and mass spectrometry (GC-MS). Only VOCs with significantly higher concentrations in breath gas samples compared to room air samples were taken into consideration. Six VOCs that belonged to the chemical classes of hydrocarbons and alcohols were identified presenting significantly different concentrations before and after feeding. Selected hydrocarbons showed a concentration pattern that was characterized by an initial increase 60 min after food intake, and a subsequent gradual decrease. Results emphasize consideration of physiological effects on exhaled VOC concentrations due to food intake with respect to standardized protocols of sample collection and critical evaluation of results. PMID:26670078

  1. Environmental Conditions Affect Exhalation of H3N2 Seasonal and Variant Influenza Viruses and Respiratory Droplet Transmission in Ferrets.

    Kortney M Gustin

    Full Text Available The seasonality of influenza virus infections in temperate climates and the role of environmental conditions like temperature and humidity in the transmission of influenza virus through the air are not well understood. Using ferrets housed at four different environmental conditions, we evaluated the respiratory droplet transmission of two influenza viruses (a seasonal H3N2 virus and an H3N2 variant virus, the etiologic virus of a swine to human summertime infection and concurrently characterized the aerosol shedding profiles of infected animals. Comparisons were made among the different temperature and humidity conditions and between the two viruses to determine if the H3N2 variant virus exhibited enhanced capabilities that may have contributed to the infections occurring in the summer. We report here that although increased levels of H3N2 variant virus were found in ferret nasal wash and exhaled aerosol samples compared to the seasonal H3N2 virus, enhanced respiratory droplet transmission was not observed under any of the environmental settings. However, overall environmental conditions were shown to modulate the frequency of influenza virus transmission through the air. Transmission occurred most frequently at 23°C/30%RH, while the levels of infectious virus in aerosols exhaled by infected ferrets agree with these results. Improving our understanding of how environmental conditions affect influenza virus infectivity and transmission may reveal ways to better protect the public against influenza virus infections.

  2. Phosphogypsum as an alternative building material: preliminary modeling and simulation of radon-222 exhalation from blocks and indoor accumulation

    Phosphogypsum is a by-product from the phosphate fertilizer industry and its large-scale utilization as an alternative construction material copes with radiological issues related to radon-222. Zero-order models for radon-222 exhalation from phosphogypsum building blocks and its time-varying accumulation in closed domains (e.g. indoor accumulation) presume homogeneous distribution of radon-222 throughout the enclosure. Having in mind radiological protection design, exhalation characterization of a block sample is a valuable parameter for the corresponding building performance simulation and it can be accomplished by placing a test block inside a test chamber together with a suitable nuclear detector (their relative positioning depends on the chamber geometry). As breakdown of the uniform concentration hypothesis is likely to occur, this preliminary work numerically investigates such model oversimplification. Along with emanation and decay processes, the present mathematical model assumes time-dependent two-dimensional diffusion-dominant mass transfer in a domain containing a sample of porous material, namely the phosphogypsum block of finite thickness. Conversely, as the test chamber is quite small and air-tight closed, convective mass transfer is neglected. Numerically simulated results have confirmed that a non-uniform radon-222 distribution takes place, which can obviously influence the position of the nuclear detector (or its primary element), thus affecting its readings. (author)

  3. Exhaled Eicosanoids following Bronchial Aspirin Challenge in Asthma Patients with and without Aspirin Hypersensitivity: The Pilot Study

    L. Mastalerz

    2012-01-01

    Full Text Available Background. Special regulatory role of eicosanoids has been postulated in aspirin-induced asthma. Objective. To investigate effects of aspirin on exhaled breath condensate (EBC levels of eicosanoids in patients with asthma. Methods. We determined EBC eicosanoid concentrations using gas chromatography/mass spectrometry (GC-MS and high-performance liquid chromatography/mass spectrometry (HPLC-MS2 or both. Determinations were performed at baseline and following bronchial aspirin challenge, in two well-defined phenotypes of asthma: aspirin-sensitive and aspirin-tolerant patients. Results. Aspirin precipitated bronchial reactions in all aspirin-sensitive, but in none of aspirin-tolerant patients (ATAs. At baseline, eicosanoids profile did not differ between both asthma groups except for lipoxygenation products: 5- and 15-hydroxyeicosatetraenoic acid (5-, 15-HETE which were higher in aspirin-induced asthma (AIA than inaspirin-tolerant subjects. Following aspirin challenge the total levels of cysteinyl-leukotrienes (cys-LTs remained unchanged in both groups. The dose of aspirin had an effect on magnitude of the response of the exhaled cys-LTs and prostanoids levels only in AIA subjects. Conclusion. The high baseline eicosanoid profiling of lipoxygenation products 5- and 15-HETE in EBC makes it possible to detect alterations in aspirin-sensitive asthma. Cysteinyl-leukotrienes, and eoxins levels in EBC after bronchial aspirin administration in stable asthma patients cannot be used as a reliable diagnostic index for aspirin hypersensitivity.

  4. Effect of exhalation exercise on trunk muscle activity and oswestry disability index of patients with chronic low back pain.

    Kang, Jeong-Il; Jeong, Dae-Keun; Choi, Hyun

    2016-06-01

    [Purpose] This study investigated the effect of exhalation exercises on trunk muscle activity and Oswestry Disability Index by inducing trunk muscle activity through increasing intra-abdominal pressure and activating muscles, contributing to spinal stability. [Subjects and Methods] This intervention program included 20 male patients with chronic low back pain. A total of 10 subjects each were randomly assigned to an exhalation exercise group as the experimental group and a spinal stabilization exercise group as the control group. [Results] There were significant differences in the activities of the rectus abdominis, transverse abdominis, external oblique abdominal, and erector spinae muscles as well as in the Oswestry Disability Index within the experimental group. There were meaningful differences in the activities of the rectus abdominis, external oblique abdominal, and erector spinae muscles and in the Oswestry Disability Index within the control group. In addition, there was a meaningful intergroup difference in transverse abdominis muscle activity alone and in the Oswestry Disability Index. [Conclusion] The breathing exercise effectively increased muscle activity by training gross and fine motor muscles in the trunk. Moreover, it was verified as a very important element for strengthening body stability because it both released and prevented low back pain. PMID:27390406

  5. Relationships between adult asthma and oxidative stress markers and pH in exhaled breath condensate: a systematic review.

    Aldakheel, F M; Thomas, P S; Bourke, J E; Matheson, M C; Dharmage, S C; Lowe, A J

    2016-06-01

    Oxidative stress has a recognized role in the pathophysiology of asthma. Recently, interest has increased in the assessment of pH and airway oxidative stress markers. Collection of exhaled breath condensate (EBC) and quantification of biomarkers in breath samples can potentially indicate lung disease activity and help in the study of airway inflammation, and asthma severity. Levels of oxidative stress markers in the EBC have been systematically evaluated in children with asthma; however, there is no such systematic review conducted for adult asthma. A systematic review of oxidative stress markers measured in EBC of adult asthma was conducted, and studies were identified by searching MEDLINE and SCOPUS databases. Sixteen papers met the inclusion criteria. Concentrations of exhaled hydrogen ions, nitric oxide products, hydrogen peroxide and 8-isoprostanes were generally elevated and related to lower lung function tests in adults with asthma compared to healthy subjects. Assessment of EBC markers may be a noninvasive approach to evaluate airway inflammation, exacerbations, and disease severity of asthma, and to monitor the effectiveness of anti-inflammatory treatment regimens. Longitudinal studies, using standardized analytical techniques for EBC collection, are required to establish reference values for the interpretation of EBC markers in the context of asthma. PMID:26896172

  6. Technique and clinical applications of full-inflation and end-exhalation controlled-ventilation chest CT in infants and young children

    Background. The inability of young children to cooperate with breath holding limits the usefulness of chest CT. Objective. To describe the technique and utility of a non-invasive method called controlled-ventilation CT (CVCT) for obtaining motion-free full-inflation and end-exhalation images of the lung in infants and young children. Materials and methods. Eighty-seven children (ages 1 week to 5 years, mean 2 years) underwent CVCT of the chest during suspended respiration at full-lung inflation and end-exhalation for a variety of clinical indications. Respiratory pauses were produced using conscious sedation and positive-pressure face-mask ventilation. Forty-one of 87 children had recordings of respiratory motion during CVCT. Results. Respiratory pause lengths increased with age (P < 0.003), were highly reproducible (r = 0.85), and lasted sufficiently long to be practical for full-inflation (24 ± 9 s) and end-exhalation (12 ± 5 s) CT scanning. Full-inflation CVCT was useful in evaluating tracheal and bronchial stenosis, bronchial wall thickening, early bronchiectasis, bronchial fistula, extent of interstitial fibrosis, and lung nodules. End-exhalation CVCT was useful in evaluating tracheomalacia and air trapping. Conclusion. Controlled-ventilation chest CT is a practical and reliable technique that promises to be clinically useful for a number of clinical indications in infants and young children. (orig.)

  7. In-phase dynamics of the exhalation sequence in Popocatépetl volcano and slow-slip events in Cocos-North American plate boundary

    Alvarez-Ramirez, Jose; Sosa, Eliceo; Hernandez-Martinez, Eliseo

    2011-02-01

    It has long been considered that the Trans-Mexican Volcanic Belt (TMVB) is related to subduction along the Middle America trench. Within this view, it is expected that the tectonic dynamics of the Cocos plate can be reflected, to some extent, in the Popocatépetl's volcanic activity This work uses detrended fluctuation analysis, a method borrowed from statistical mechanics, to quantify the fractality and autocorrelations in the exhalation sequence of the Popocatepetl. It is found that the autocorrelations exhibit cyclic, non-periodic, dynamics with dominant periods of the order of 0.85 to 1.25 years. Interestingly, it is shown that the occurrence of slow-slip events in Southern (Guerrero and Oaxaca) Mexico coincides with peaks of the autocorrelation cycle of the exhalation sequence. The result suggests the use of the volcano exhalation sequence as a proxy of aseismic events in the Cocos-North American plate boundary. That is, by monitoring the autocorrelation dynamics of the exhalation sequence in the Popocatepetl, one could be able to suspect the occurrence of a slow-slip event in Southern Mexico.

  8. A NON-INVASIVE DIAGNOSIS OF INTESTINAL ISCHEMIA BY EXHALED BREATH ANALYSIS USING GAS CHROMATOGRAPHY AND MASS SPECTROMETRY-PRELIMINARY RESULTS

    To explore the potential of exhaled breath analysis by Column Chromatography-Mass Spectrometry (GC-MS) as a non invasive and sensitive approach to evaluate mesenteric ischemia in pigs. Domestic pigs (n=3) were anesthetized with Guaifenesin/ Fentanyl/ Ketamine/ Xylazine...

  9. Determination of 8-iso-prostaglandin F2α in exhaled breath condensate using combination of immunoseparation and LC–ESI-MS/MS

    Syslová, K.; Kačer, P.; Kuzma, Marek; Klusáčková, P.; Fenclová, Z.; Lebedová, J.; Pelclová, D.

    2008-01-01

    Roč. 867, č. 1 (2008), s. 8-14. ISSN 1570-0232 R&D Projects: GA MZd(CZ) NR8107 Institutional research plan: CEZ:AV0Z50200510 Keywords : exhaled breath condensate * immunoseparation Subject RIV: EE - Microbiology, Virology Impact factor: 2.500, year: 2008

  10. Effect of Shisha (Waterpipe) Smoking on Lung Functions and Fractional Exhaled Nitric Oxide (FeNO) among Saudi Young Adult Shisha Smokers

    Meo, Sultan Ayoub; AlShehri, Khaled Ahmed; AlHarbi, Bader Bandar; Barayyan, Omar Rayyan; Bawazir, Abdulrahman Salem; Alanazi, Omar Abdulmohsin; Al-Zuhair, Ahmed Raad

    2014-01-01

    Shisha (waterpipe) smoking is becoming a more prevalent form of tobacco consumption, and is growing worldwide, particularly among the young generation in the Middle East. This cross-sectional study aimed to determine the effects of shisha smoking on lung functions and Fractional Exhaled Nitric Oxide (FeNO) among Saudi young adults. We recruited 146 apparently healthy male subjects (73 control and 73 shisha smokers). The exposed group consisted of male shisha smokers, with mean age 21.54 ± 0.41 (mean ± SEM) range 17–33 years. The control group consisted of similar number (73) of non-smokers with mean age 21.36 ± 0.19 (mean ± SEM) range 18–28 years. Between the groups we considered the factors like age, height, weight, gender, ethnicity and socioeconomic status to estimate the impact of shisha smoking on lung function and fractional exhaled nitric oxide. Lung function test was performed by using an Spirovit-SP-1 Electronic Spirometer. Fractional Exhaled Nitric Oxide (FeNO) was measured by using Niox Mino. A significant decrease in lung function parameters FEV1, FEV1/FVC Ratio, FEF-25%, FEF-50%, FEF-75% and FEF-75-85% was found among shisha smokers relative to their control group. There was also a significant reduction in the Fractional Exhaled Nitric Oxide among Shisha smokers compared to control group. PMID:25233010

  11. Effect of Shisha (Waterpipe Smoking on Lung Functions and Fractional Exhaled Nitric Oxide (FeNO among Saudi Young Adult Shisha Smokers

    Sultan Ayoub Meo

    2014-09-01

    Full Text Available Shisha (waterpipe smoking is becoming a more prevalent form of tobacco consumption, and is growing worldwide, particularly among the young generation in the Middle East. This cross-sectional study aimed to determine the effects of shisha smoking on lung functions and Fractional Exhaled Nitric Oxide (FeNO among Saudi young adults. We recruited 146 apparently healthy male subjects (73 control and 73 shisha smokers. The exposed group consisted of male shisha smokers, with mean age 21.54 ± 0.41 (mean ± SEM range 17–33 years. The control group consisted of similar number (73 of non-smokers with mean age 21.36 ± 0.19 (mean ± SEM range 18–28 years. Between the groups we considered the factors like age, height, weight, gender, ethnicity and socioeconomic status to estimate the impact of shisha smoking on lung function and fractional exhaled nitric oxide. Lung function test was performed by using an Spirovit-SP-1 Electronic Spirometer. Fractional Exhaled Nitric Oxide (FeNO was measured by using Niox Mino. A significant decrease in lung function parameters FEV1, FEV1/FVC Ratio, FEF-25%, FEF-50%, FEF-75% and FEF-75–85% was found among shisha smokers relative to their control group. There was also a significant reduction in the Fractional Exhaled Nitric Oxide among Shisha smokers compared to control group.

  12. Development of a protocol to measure volatile organic compounds in human breath: a comparison of rebreathing and on-line single exhalations using proton transfer reaction mass spectrometry

    Analysis of volatile organic compounds (VOCs) on human breath has great potential as a non-invasive diagnostic technique. It is, therefore, surprising that no single, standard procedure has evolved for breath sampling. Here we present a novel repeated-cycle isothermal rebreathing method, where one cycle comprises five rebreaths, which could be adopted for breath analysis of VOCs. For demonstration purposes, we present measurements of three common breath VOCs: isoprene, acetone and methanol. Their concentrations measured in breath are shown to increase with number of rebreaths until a plateau value is reached by at least 20 rebreaths. The average ratio of plateau concentration to single mixed expired breath concentration was found to be 1.92 ± 0.57 for isoprene, 1.25 ± 0.13 for acetone and 1.12 ± 0.12 for methanol (mean ± standard deviation). Measurements from on-line single exhalations are presented which demonstrate a positive slope in the time-dependent expirograms of isoprene and acetone. The slope of the isoprene expirogram is persistently linear and the end-expired concentration of isoprene is highly variable in the same subject depending on the duration of exhalation. End-expired values of acetone are not as sensitive to the length of exhalation, and are the same to within measurement uncertainty for any duration of exhalation for any subject. It is concluded that uncontrolled single on-line exhalations are not suitable for the reliable measurement of isoprene in the breath and that rebreathing can be the basis of an easily tolerated protocol for the reliable collection of breath samples

  13. Dispersion of exhaled droplet nuclei in a two-bed hospital ward with three different ventilation systems

    Qian, H.; Li, Y.; Nielsen, Peter V.;

    2006-01-01

    Effective ventilation in general hospital wards is important for controlling the airborne transmission of infectious respiratory diseases. Experiments have been carried out to increase our understanding of the interaction of the breathing flows of two individuals in a full-scale experimental...... hospital ward with three ventilation systems, i.e. mixing, downward and displacement ventilation. Two life-size breathing thermal manikins were used to simulate a source patient and a receiving patient. The exhalation jet from a bed-lying manikin was visualized using smoke. N2O was used as tracer gas to...... with displacement ventilation. This work is useful for identifying an appropriate ventilation method that can remove droplet nuclei more effectively and minimize the risk of cross-infections in a hospital ward environment....

  14. Monitoring the ionic content of exhaled breath condensate in various respiratory diseases by capillary electrophoresis with contactless conductivity detection.

    Greguš, Michal; Foret, František; Kindlová, Dagmar; Pokojová, Eva; Plutinský, Marek; Doubková, Martina; Merta, Zdeněk; Binková, Ilona; Skřičková, Jana; Kubáň, Petr

    2015-06-01

    The analysis of an ionic profile of exhaled breath condensate (EBC) by capillary electrophoresis with contactless conductivity detection and double opposite end injection, is demonstrated. A miniature sampler made from a 2 ml syringe and an aluminium cooling cylinder was used for the fast collection of EBC (under one minute). Analysis of the collected EBC was performed in a 60 mM 2-(N-morpholino)ethanesulfonic acid, 60 mM L-histidine background electrolyte with 30 µM cetyltrimethylammonium bromide and 2 mM 18-crown-6 at pH 6, and excellent repeatability of migration times (RSD  acetate, lactate). The developed collection system and method provides a highly reproducible and fast way of collecting and analyzing EBC, with future applicability in point-of-care diagnostics. PMID:25944821

  15. Comparisons of the complementary effect on exhaled nitric oxide of salmeterol vs montelukast in asthmatic children taking regular inhaled budesonide

    Buchvald, Frederik; Bisgaard, Hans

    2003-01-01

    BACKGROUND: Inhaled, long-acting beta2-agonists or antileukotrienes are alternatives as add-on therapy for asthmatic children taking regular inhaled steroids. Any complementary effects would be relevant to the choice between these alternatives. Exhaled nitric oxide (FeNO) may reflect these effects....... OBJECTIVE: To compare the control of FeNO provided by salmeterol or montelukast add-on therapy in asthmatic children undergoing regular maintenance treatment with a daily dose of 400 microg of budesonide. METHODS: The study included children with increased FeNO despite regular treatment with budesonide, 400...... microg/d, and normal lung function. Montelukast, 5 mg/d, salmeterol, 50 microg twice daily, or placebo was compared as add-on therapy to budesonide, 400 microg, in a randomized, double-blind, double-dummy, crossover study. RESULTS: Twenty-two children completed the trial. The geometric mean FeNO level...

  16. Luminol/H2O2 chemiluminescence detector for the analysis of nitric oxide in exhaled breath.

    Robinson, J K; Bollinger, M J; Birks, J W

    1999-11-15

    A new instrument for the detection of nitric oxide has been developed and applied to the analysis of exhaled breath. The instrument is based on conversion of NO to NO2, using the oxidant chromium trioxide, followed by detection of chemiluminescence in the reaction of NO2 with an alkaline luminol/H2O2 solution. The presence of H2O2 is found to enhance the sensitivity of NO2 detection by a factor of approximately 20. A bundle of porous polypropylene hollow fiber membranes is used to bring the gaseous sample into contact with the luminol solution. Chemiluminescence occurring within the translucent hollow fibers is detected using a miniature photomultiplier tube. The limit of detection for NO is 0.3 ppbv for S/N = 3, and the 1/e response time is 2 s. A large interference resulting from the 4-6% CO2 concentration in exhaled breath is removed by use of an ascarite scrubber in the air stream. Breath measurements of NO were made using a sampling technique developed by Sensor Medics (Yorba Linda, CA) with simultaneous detection using the luminol/H2O2 and NO + O3 chemiluminescence techniques. The two instruments were found to be in excellent agreement. Nitric oxide levels were in the range 6.0-22.0 ppbv for healthy individuals and 40.0-80.0 ppbv for individuals with asthma or a respiratory infection. This new detector offers the advantages of compact size, low cost, and a simple configuration compared to NO detectors based on NO + O3 chemiluminescence. PMID:10575964

  17. Investigation of the climatic extremes influence on the humane adaptive capacity by mass spectrometric analysis of exhaled breath condensate

    Ryabokon, Anna; Larina, Irina; Kononikhin, Alexey; Starodubtceva, Nataliia; Popov, Igor; Nikolaev, Eugene; Varfolomeev, Sergey

    Global climate change, which causes abnormal fluctuations in temperature and rainfall, has adverse effects on human health. Particularly people suffer with cardiovascular and respiratory system disease. Our research was concentrated on the changes in the regulation and adaptation systems of human organism related to hyperthermia and polluted air influence. Healthy individuals with the age from 22 to 45 years were isolated during 30 days in the ground based experimental facility located at Institute of medico-biological problems RAS (Moscow, Russia). In the ground based facility artificially climatic conditions of August, 2010 in Moscow were created. Exhaled breath condensate was collected before and after isolation by R-Tube collector, freeze dried, treated by trypsin and analyzed by nanoflow LC-MS/MS with a 7-Tesla LTQ-FT Ultra mass spectrometer (Thermo Electron, Bremen, Germany). Database search was performed using Mascot Server 2.2 software (Matrix Science, London, UK). Investigation of exhaled breath condensate (EBC) collected from participants of the 30 days isolation with hyper thermic and polluted air climate conditions was performed. After isolation reduction of the protein number was observed. Loss endothelial C receptor precursor - the main physiological anticoagulant - correlate with the clinical data of physicians to increase the propensity to thrombosis. Also COP9 signalosome protein, positive regulator of ubiquitin was identified in all EBC samples before isolation and was not detected for more than a half of donors after isolation. This phenomena may be due to violation of ubiquitin protection system of the cells from harmful proteins. During isolation the air was cleared from microdisperse particles.

  18. Visualization of exhaled hydrogen sulphide on test paper with an ultrasensitive and time-gated luminescent probe.

    Zhang, Ruilong; Liu, Shijiang; Wang, Jianping; Han, Guangmei; Yang, Linlin; Liu, Bianhua; Guan, Guijian; Zhang, Zhongping

    2016-08-01

    Luminescent chemosensors for hydrogen sulphide (H2S) are of great interest because of the close association of H2S with our health. However, current probes for H2S detection have problems such as low sensitivity/selectivity, poor aqueous-solubility or interference from background fluorescence. This study reports an ultrasensitive and time-gated "switch on" probe for detection of H2S, and its application in test paper for visualization of exhaled H2S. The complex probe is synthesized with a luminescent Tb(3+) centre and three ligands of azido (-N3) substituted pyridine-2,6-dicarboxylic acid, giving the probe high hydrophilicity and relatively fast reaction dynamics with H2S because there are three -N3 groups in each molecule. The introduced -N3 group as a strong electron-withdrawing moiety effectively changes the energy level of ligand via intramolecular charge transfer (ICT), and thus breaks the energy transferring from ligand to lanthanide ion, resulting in quenching of Tb(3+) luminescence. On addition of H2S, the -N3 group can be reduced to an amine group to break the process of ICT, and the luminescence of Tb(3+) is recovered at a nanomolar sensitivity level. With a long lifetime of luminescence of Tb(3+) centre (1.9 ms), use of a time-gated technique effectively eliminates the background fluorescence by delaying fluorescence collection for 0.1 ms. The test paper imprinted by the complex probe ink can visualize clearly the trace H2S gas exhaled by mice. PMID:27291706

  19. Evaluation of radon adsorption characteristics of a coconut shell-based activated charcoal system for radon and thoron removal applications

    Radon (222Rn), thoron (220Rn), and their decay products contribute a major fraction (more than 50%) of doses received from ionisation radiation in public domain indoor environments and occupation environments such as uranium mines, thorium plants, and underground facilities, and are recognised as important radiological hazardous materials, which need to be controlled. This paper presents studies on the removal of 222Rn and 220Rn from air using coconut shell-based granular activated charcoal cylindrical adsorber beds. Experiments were conducted to evaluate the 222Rn and 220Rn adsorption characteristics, and the mitigation efficiency of coconut-based activated charcoal available in India. The performance parameters evaluated include breakthrough time (τ) and adsorption coefficient (K), and degassing characteristics of the charcoal bed of varying dimensions at different flow rates. While the breakthrough for 222Rn occurred depending on the dimension of the adsorber bed and flow rates, for 220Rn, the breakthrough did not occur. The breakthrough curve exhibited a stretched S-shape response, instead of the theoretically predicted sharp step function. The experiments confirm that the breakthrough time individually satisfies the quadratic relationship with respect to the diameter of the bed, and the linear relationship with respect to the length, as predicted in the theory. The K value varied in the range of 2.3–4.12 m3 kg−1 with a mean value of 2.99 m3 kg−1. The K value was found to increase with the increase in flow rate. Heating the charcoal to ∼100 °C resulted in degassing of the adsorbed 222Rn, and the K of the degassed charcoal and virgin charcoal were found to be similar with no deterioration in performance indicating the re-usability of the charcoal. - Highlights: • 222Rn and 220Rn removal from air using activated charcoal bed is demonstrated. • Breakthrough time and adsorption coefficient were evaluated. • A sustained mitigation factor

  20. Study of Rn-222 exhalation in phosphogypsum through the adsorption technique in activated coal; Estudo da exalacao de Rn-222 em fosfogesso por meio da tecnica de adsorcao em carvao ativado

    Nisti, Marcelo Bessa; Campos, Marcia Pires de, E-mail: mbnisti@ipen.b, E-mail: mpcampos@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-10-26

    The radon exhalation was estimated through the adsorption in activated carbon technique. Classified as TENORM, the radon exhalation determination on the phosphogypsum piles was performed through the adsorption ratio of radon in activated carbon, from the concentration of descendants of {sup 222}Rn, {sup 214}Pb and {sup 214}Bi obtained by gamma spectrometry. The results obtained in this work were compatibles with the values found in the literature

  1. Nitric oxide in exhaled and aspirated nasal air as an objective measure of human response to isopropanol oxidation products and pthtalate esters in indoor air

    Lagercrantz, Love Per; Famula, Basia; Sundell, Jan

    2005-01-01

    exposed to 2 commonly occurring indoor air pollutants and to a clean reference condition for 4.5 hours. Assessments of the environment were obtained using questionnaires. The polluted conditions were perceived as worse than the reference condition. After exposure to the two polluted conditions a small......The use of Nitric Oxide (NO) concentration in exhaled and aspirated nasal air to assess human response to indoor air pollution was tested in a climate chamber exposure experiment. The concentration of NO was measured using a chemiluminescence NO analyser. Sixteen healthy female subjects were...... increase in NO concentration (+2.7% and +7.2%) in exhaled air was observed. After exposure to the reference condition the mean NO concentration was significantly reduced (-14.3%) compared to before exposure. NO in nasal air was unaffected by the exposures. The results indicate an association between...

  2. Validation of a geographic information system for the evaluation of the soil radon exhalation potential in South-Tyrol and Veneto (Italy)

    The PERS (soil radon exhalation potential) project was promoted by ANPA (Italian Environmental Protection Agency) together with the Universita Cattolica del Sacro Cuore of Rome: the aim was to produce a geographic information system allowing the discovery of regions with different radon exhalation potential starting from some territorial knowledge. Some environmental measurements were carried out within this project in selected areas in South-Tyrol and Veneto. The measurement of radon in springwater and groundwater as well as in soil gas plays a decisive role for the validation of the algorithm for computing the PERS. Along with technical aspects, a possible use of the PERS method by the Regional Environmental Protection Agencies and by other agencies is discussed with the scope of identifying radon prone areas, as stated in the Italian 'Decreto Legislativo' 26 May 2000, n. 241. Moreover the forecasting power of PERS regarding indoor radon concentration is analysed. (author)

  3. Content of the Nitrogen Oxide Metabolites in a Condensate of Exhaling Air in Children with a Bronchial Asthma Control Different Level

    Eliseeva T.I.

    2010-12-01

    Full Text Available Aim of investigation is establishment of regularity of the nitrogen oxide metabolite content change in the exhaling air condensate (EAC in children with a bronchial asthma control different level, assessed with a use of the ACQ day and week scales (Asthma Control Questionnaire. Materials and Methods. A summarized content of nitrites and nitrates in the exhaling air condensate in 61 infants with a bronchial asthma control different level is analyzed; it is analyzed in a disease dynamics in a part of them. Results. A summarized content of the nitrogen oxide metabolites in the EAC in patients with an absolute and full control of a bronchial asthma, not receiving the glucocorticosteroid therapy, was trustworthy higher than in patients, receiving that therapy. A trustworthy dependence between a summarized content of the nitrogen oxide metabolites in the EAC and a level of a bronchial asthma control in patients, receiving a similar therapy (with the glucocorticosteroid inclusion, is established.

  4. Correlation of exhaled nitric oxide, nasal nitric oxide and atopic status: A cross-sectional study in bronchial asthma and allergic rhinitis

    Nitesh Gupta; Nitin Goel; Raj Kumar

    2014-01-01

    Objective: Exhaled nitric oxide (FE NO ) and nasal nitric oxide (n NO) measurement is an area of ongoing research in the study of airway inflammation. The atopic status is known to influence the levels of FE NO and n NO. This study was undertaken to study the relationship between nitric oxide measurements in bronchial asthma and allergic rhinitis along with their correlation with atopic profile of Indian population. Materials and Methods: Ninety subjects were recruited for the study comprisin...

  5. The intake of maqui (Aristotelia chilensis) berry extract normalizes H2O2 and IL-6 concentrations in exhaled breath condensate from healthy smokers - an explorative study

    VERGARA, DANIELA; Ávila, Daniela; Escobar, Elizabeth; Carrasco-Pozo, Catalina; Sánchez, Andrés; Gotteland, Martin

    2015-01-01

    Background Respiratory diseases are associated with pulmonary oxidative stress and inflammatory processes. Though studies in animal models suggest that dietary polyphenols improve lung injury, no intervention studies were carried out in humans. The aim of this study was to determine whether the intake of an anthocyanin-rich maqui extract improved H2O2 and IL-6 concentrations in exhaled breath condensates (EBCs) from asymptomatic smokers. Findings 15 asymptomatic smokers with mild cigarette sm...

  6. Abiotic methane flux from the Chimaera seep and Tekirova ophiolites (Turkey): Understanding gas exhalation from low temperature serpentinization and implications for Mars

    Etiope, G.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Roma2, Roma, Italia; Schoell, M.; GasConsult International Inc., Berkeley, USA; Hosgörmez, H.; Istanbul University, Engineering Faculty, Geology Department, Istanbul, Turkey

    2011-01-01

    The emission of abiotic methane (CH4) into the atmosphere from low temperature serpentinization in ophiolitic rocks is documented to date only in four countries, the Philippines, Oman, New Zealand, and Turkey. Serpentinization produces large amounts of hydrogen (H2) which in theory may react with CO2 or CO to form hydrocarbons (Fischer–Tropsch Type synthesis, FTT). Similar mechanisms have been invoked to explain the CH4 detected on Mars, so that understanding flux and exhalation m...

  7. Prolonged Treatment with Inhaled Corticosteroids does not Normalize High Activity of Matrix Metalloproteinase-9 in Exhaled Breath Condensates of Children with Asthma

    Grzela, Katarzyna; Zagorska, Wioletta; Krejner, Alicja; Litwiniuk, Malgorzata; Zawadzka-Krajewska, Anna; Banaszkiewicz, Aleksandra; Kulus, Marek; Grzela, Tomasz

    2015-01-01

    The airway remodeling in asthma is associated with increased amount of matrix metalloproteinase (MMP)-9. High levels of MMP-9 were found in mucosal biopsies, sputum and in exhaled breath condensates (EBC) of asthma patients. However, there are no data concerning real in vivo activity. Inhaled corticosteroids are effective in asthma control, but it is unclear, whether they only attenuate inflammation, or also protect against progressive remodeling of respiratory tract. Therefore, the aim of th...

  8. Exhaled carbon monoxide and its associations with smoking, indoor household air pollution and chronic respiratory diseases among 512,000 Chinese adults.

    Zhang, Q.; Li, L; Smith, M; Y. Guo; Whitlock, G.; Bian, Z.; Kurmi, O; Collins, R.; Chen, J.; S. Lv; Pang, Z.; Chen, C.; Chen, N.; Xiong, Y; R. Peto

    2013-01-01

    Background Exhaled carbon monoxide (COex) level is positively associated with tobacco smoking and exposure to smoke from biomass/coal burning. Relatively little is known about its determinants in China despite the population having a high prevalence of smoking and use of biomass/coal. Methods The China Kadoorie Biobank includes 512 000 participants aged 30-79 years recruited from 10 diverse regions. We used linear regression and logistic regression methods to assess the associations of COex l...

  9. Exhaled volatile organic compounds in patients with non-small cell lung cancer: cross sectional and nested short-term follow-up study

    Acampa Olga; Goldoni Matteo; Corradi Massimo; Carbognani Paolo; Poli Diana; Balbi Bruno; Bianchi Luca; Rusca Michele; Mutti Antonio

    2005-01-01

    Abstract Background Non-invasive diagnostic strategies aimed at identifying biomarkers of lung cancer are of great interest for early cancer detection. The aim of this study was to set up a new method for identifying and quantifying volatile organic compounds (VOCs) in exhaled air of patients with non-small cells lung cancer (NSCLC), by comparing the levels with those obtained from healthy smokers and non-smokers, and patients with chronic obstructive pulmonary disease. The VOC collection and...

  10. Impact of chorioamnionitis on exhaled nitric oxide and endotracheal aspirate levels of nitrites-nitrates and interleukin-8 in mechanically ventilated preterm neonates

    Figueras-Aloy, Josep; Salvia-Roiges, M.Dolors; Rodríguez-Miguélez, J.Manuel; Miracle-Echegoyen, Xavier; Botet-Mussons, Francisco; Marín-Soria, J.Luís; Carbonell-Estrany, Xavier

    2011-01-01

    Abstract Objectives: To assess the influence of maternal chorioamnionitis on early exhaled nitric oxide (NO) and levels of nitrites-nitrates and interleukin (IL) IL-8 in endotracheal aspirate fluid in mechanically ventilated preterm neonates. Study Design: Cross-sectional study. Patient-Subject Selection: Between September 2007 and August 2009, 54 mechanically ventilated preterm neonates were included. Patients were divided into two groups according to the presence or absenc...

  11. Near-IR laser-based spectrophotometer for comparative analysis of isotope content of CO{sub 2} in exhale air samples

    Stepanov, E V; Glushko, A N; Kasoev, S G; Koval' , A V; Lapshin, D A [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)

    2011-12-31

    We present a laser spectrophotometer aimed at high-accuracy comparative analysis of content of {sup 12}CO{sub 2} and {sup 13}CO{sub 2} isotope modifications in the exhale air samples and based on a tunable near-IR diode laser (2.05 {mu}m). The two-channel optical scheme of the spectrophotometer and the special digital system for its control are described. An algorithm of spectral data processing aimed at determining the difference in the isotope composition of gas mixtures is proposed. A few spectral regions (near 4880 cm{sup -1}) are determined to be optimal for analysis of relative content of {sup 12}CO{sub 2} and {sup 13}CO{sub 2} in the exhale air. The use of the proposed spectrophotometer scheme and the developed algorithm makes the results of the analysis less susceptible to the influence of the interference in optical elements, to the absorption in the open atmosphere, to the slow drift of the laser pulse envelope, and to the offset of optical channels. The sensitivity of the comparative analysis of the isotope content of CO{sub 2} in exhale air samples, achieved using the proposed scheme, is estimated to be nearly 0.1 Per-Mille-Sign .

  12. 13CO2/12CO2 ratio analysis in exhaled air by lead-salt tunable diode lasers for noninvasive diagnostics in gastroenterology

    Stepanov, Eugene V.; Zyrianov, Pavel V.; Miliaev, Valerii A.; Selivanov, Yurii G.; Chizhevskii, Eugene G.; Os'kina, Svetlana; Ivashkin, Vladimir T.; Nikitina, Elena I.

    1999-07-01

    An analyzer of 13CO2/12CO2 ratio in exhaled air based on lead-salt tunable diode lasers is presented. High accuracy of the carbon isotope ratio detection in exhaled carbon dioxide was achieved with help of very simple optical schematics. It was based on the use of MBE laser diodes operating in pulse mode and on recording the resonance CO2 absorption at 4.2 micrometers . Special fast acquisition electronics and software were applied for spectral data collection and processing. Developed laser system was tested in a clinical train aimed to assessment eradication efficiency in therapy of gastritis associated with Helicobacter pylori infection. Data on the 13C-urea breath test used for P.pylori detection and obtained with tunable diode lasers in the course of the trail was compared with the results of Mass-Spectroscopy analysis and histology observations. The analyzer can be used also for 13CO2/12CO2 ratio detection in exhalation to perform gastroenterology breath test based on using other compounds labeled with stable isotopes.

  13. Diseño y evaluación de un equipo para obtener aire espirado condensado Design and evaluation of a device for collecting exhaled breath condensate

    Oscar Florencio Araneda Valenzuela

    2009-01-01

    Full Text Available El análisis de muestras de aire espirado condensado ha cobrado gran relevancia en los últimos años como método no invasivo de estudio de la fisiología y las enfermedades de origen pulmonar. En el presente trabajo se describe un equipo para tomar muestras de aire espirado condensado de bajo costo, fácil de fabricar, de transportar al terreno y que permite tomar muestras en forma simultánea. La concentración de metabolitos relativos a procesos inflamatorios y al daño oxidativo (pH, peróxido de hidrógeno y nitrito de muestras de aire espirado condensado obtenido con este equipo son comparables a los reportados con otros previamente.In recent years, the analysis of exhaled breath condensate samples has been given great weight as a noninvasive methodology of studying physiology and lung diseases. The present study describes a device for measuring exhaled breath condensate that is affordable, easily constructed, portable and suitable for use in the field, as well as allowing the collection of simultaneous samples. The results obtained with this device in terms of the concentrations of pH, peroxide oxide and nitrite, metabolites related to inflammatory and oxidative damage, in exhaled breath condensate samples are comparable to those obtained with other devices previously described.

  14. Characterization of airway inflammation in patients with COPD using fractional exhaled nitric oxide levels: a pilot study

    Donohue JF

    2014-07-01

    Full Text Available James F Donohue,1 Nancy Herje,2 Glenn Crater,2 Kathleen Rickard2 1Department of Medicine, University of North Carolina School of Medicine, Chapel Hill, NC, USA; 2Aerocrine, Inc., Morrisville, NC, USA Objective: To characterize fractional exhaled nitric oxide (FeNO levels that may be indicative of Th2-mediated airway inflammation in patients with chronic obstructive pulmonary disease (COPD. Methods: This single-visit, outpatient study was conducted in 200 patients aged 40 years and older with COPD. All patients underwent spirometry and FeNO testing. COPD severity was classified according to the Global initiative for chronic Obstructive Lung Disease (GOLD 2010 guidelines. Results: Patients who participated in the study had a mean age of 63.9±11.3 years and a mean smoking history of 46±29 pack years. Patients had a mean forced expiratory volume in 1 second % predicted of 53.9%±22.1%. The percentage of patients classified with COPD severity Stage I, II, III, and IV was 13%, 40%, 39%, and 8%, respectively. In addition, according to current procedural terminology codes, 32% of patients were classified as mixed COPD/asthma, 26% as COPD/emphysema, and 42% as all other codes. The mean FeNO level for all patients was 15.3±17.2 parts per billion (ppb. Overall, 89% of patients had a FeNO <25 ppb, 8% had a FeNO 25–50 ppb, and 3% had a FeNO >50 ppb. The percentages of patients with FeNO in the intermediate or high ranges of FeNO were greatest among patients with mixed COPD/asthma (intermediate, 11.5%; high, 6.6% compared with COPD/emphysema (intermediate, 8%; high, 0 and all other codes (intermediate, 6.3%; high, 1.3%. Conclusion: Increases in FeNO were identified in a subset of patients with COPD, particularly in those previously diagnosed with both COPD and asthma. Since FeNO is useful for identifying patients with airway inflammation who will have a beneficial response to treatment with an inhaled corticosteroid, these data may have important

  15. Dynamic profiles of volatile organic compounds in exhaled breath as determined by a coupled PTR-MS/GC-MS study

    In this phenomenological study we focus on dynamic measurements of volatile organic compounds (VOCs) in exhaled breath under exercise conditions. An experimental setup efficiently combining breath-by-breath analyses using proton transfer reaction mass spectrometry (PTR-MS) with data reflecting the behaviour of major hemodynamic and respiratory parameters is presented. Furthermore, a methodology for complementing continuous VOC profiles obtained by PTR-MS with simultaneous SPME/GC-MS measurements is outlined. These investigations aim at evaluating the impact of breathing patterns, cardiac output or blood pressure on the observed breath concentration and allow for the detection and identification of several VOCs revealing characteristic rest-to-work transitions in response to variations in ventilation or perfusion. Examples of such compounds include isoprene, methyl acetate, butane, DMS and 2-pentanone. In particular, both isoprene and methyl acetate exhibit a drastic rise in concentration shortly after the onset of exercise, usually by a factor of about 3–5 within approximately 1 min of pedalling. These specific VOCs might also be interpreted as potentially sensitive indicators for fluctuations of blood or respiratory flow and can therefore be viewed as candidate compounds for future assessments of hemodynamics, pulmonary function and gas exchange patterns via observed VOC behaviour

  16. Effects of nasal CPAP on exhaled SIRT1 and tumor necrosis factor-α in patients with obstructive sleep apnea.

    Lin, Ching-Chi; Liaw, Shwu-Fang; Chiu, Chung-Hsin; Chen, Wei-Ji; Lin, Mei-Wei; Chang, Feng-Ting

    2016-07-01

    Exhaled breath condensate (EBC) has been used to examine airway inflammation and oxidative stress. This study aimed to evaluate if there were abnormal Sirtuin 1 (SIRT1) protein and tumor necrosis factor (TNF)-α levels in EBC and to determine if these levels could be improved after nasal continuous positive airway pressure (CPAP) treatment. Thirty-five patients with moderately severe to severe obstructive sleep apnea syndrome (OSAS) who wanted nasal CPAP treatment and 20 healthy controls were prospectively enrolled. The EBC SIRT1 protein levels and EBC TNF-α protein levels were assessed by ELISA. All patients underwent sleep studies that were repeated 3 months after nasal CPAP treatment in patients with OSAS. Results showed that in OSAS before nasal CPAP treatment, the EBC SIRT1 protein levels were lower than that in normal subjects, whereas the EBC TNF-α protein levels were higher. After nasal CPAP treatment, the EBC SIRT1 levels increased and EBC TNF-α levels decreased. In conclusion, successful treatment of OSAS by nasal CPAP can normalize the levels of EBC SIRT1 and EBC TNF-α. PMID:26976689

  17. Impact of different welding techniques on biological effect markers in exhaled breath condensate of 58 mild steel welders.

    Hoffmeyer, Frank; Raulf-Heimsoth, Monika; Lehnert, Martin; Kendzia, Benjamin; Bernard, Sabine; Berresheim, Hans; Düser, Maria; Henry, Jana; Weiss, Tobias; Koch, Holger M; Pesch, Beate; Brüning, Thomas

    2012-01-01

    Total mass and composition of welding fumes are predominantly dependent on the welding technique and welding wire applied. The objective of this study was to investigate the impact of welding techniques on biological effect markers in exhaled breath condensate (EBC) of 58 healthy welders. The welding techniques applied were gas metal arc welding with solid wire (GMAW) (n=29) or flux cored wire (FCAW) (n=29). Welding fume particles were collected with personal samplers in the breathing zone inside the helmets. Levels of leukotriene B(4) (LTB(4)), prostaglandin E(2) (PGE(2)), and 8-isoprostane (8-iso-PGF(2α)) were measured with immunoassay kits and the EBC pH was measured after deaeration. Significantly higher 8-iso-PGF(2α) concentrations and a less acid pH were detected in EBC of welders using the FCAW than in EBC of welders using the GMAW technique. The lowest LTB(4) concentrations were measured in nonsmoking welders applying a solid wire. No significant influences were found in EBC concentrations of PGE(2) based upon smoking status or type of welding technique. This study suggests an enhanced irritative effect in the lower airways of mild steel welders due to the application of FCAW compared to GMAW, most likely associated with a higher emission of welding fumes. PMID:22686312

  18. Effect of exercise duration on pro-oxidants and pH in exhaled breath condensate in humans.

    Tuesta, M; Alvear, M; Carbonell, T; García, C; Guzmán-Venegas, R; Araneda, O F

    2016-06-01

    Exercise promotes pulmonary oxidative imbalance. In this regard, some evidence has been obtained from the study of exhaled breath condensate (EBC) during urban races, in which the factors involved in the occurrence of this process are still not characterized. In this paper, under laboratory conditions, both the role of time of exercise on the generation of pro-oxidants (H2O2, NO2 (-)) and pH have been assessed in EBC of 16 under-trained subjects who completed three tests of cycloergometric exercise at low intensity (30 % of VO2 max) with a duration of 10, 30, and 90 min. Samples were obtained as follows: immediately before and at 80 min post exertion in each test. In the 90-min test, an increase in H2O2, NO2 (-) concentration in EBC at 80 min post exertion with no changes in the pH was observed. Total O2 consumption and total ventilation weakly correlated with the changes in H2O2 and NO2 (-). In conclusion, the concentration of pro-oxidants in the EBC depends on the duration of the exercise when it is performed at low intensity under laboratory conditions. PMID:27097598

  19. Measurement techniques of thoron and thoron progeny concentrations. Active and passive methods and their calibrations

    The measurements of 220Rn and its progeny concentrations are affected always by 222Rn and its progeny. Various types of measurement techniques of 220Rn and its progeny concentrations had been developed by using the differences between half lives of 222Rn and 220Rn and energies of α- and γ-radiations emitted from 222Rn and 220Rn progeny. Active 220Rn measurement techniques include the methods of ionization chamber, scintillation cell, two filter, liquid scintillation and activated charcoal. Decay, α-spectroscopy and integrating methods have used to measure 220Rn progeny concentrations collected on a filter. Passive monitors are suitable to survey mean 220Rn concentration in the living environment. Cup and activated charcoal monitors have been reported for the passive 220Rn methods. Calibrations of active and passive 220Rn monitors should be carried out in the calibration chambers with 220Rn source outside and inside, respectively. (author)

  20. Evaluation of the SF6 tracer technique for estimating methane emission rates with reference to dairy cows using a mechanistic model.

    Berends, H; Gerrits, W J J; France, J; Ellis, J L; van Zijderveld, S M; Dijkstra, J

    2014-07-21

    A dynamic, mechanistic model of the sulfur hexafluoride (SF6) tracer technique, used for estimating methane (CH4) emission rates from ruminants, was constructed to evaluate the accuracy of the technique. The model consists of six state variables and six zero-pools representing the quantities of SF6 and CH4 in rumen and hindgut fluid, in rumen and hindgut headspace, and in blood and collection canister. The model simulates flows of CH4 and SF6 through the body, subsequent eructation and exhalation and accumulation in a collection canister. The model predicts CH4 emission by multiplying the SF6 release rate of a permeation device in the rumen by the ratio of CH4:SF6 in collected air. This prediction is compared with the actual CH4 production rate, assumed to be continuous and used as a driving variable in the model. A sensitivity analysis was conducted to evaluate the effect of changes in several parameters. The predicted CH4 emission appeared sensitive to parameters affected by the difference in CH4:SF6 ratio in exhaled and eructed air respectively, viz., hindgut fractional passage rate and hindgut CH4 production. This is caused by the difference in solubility of CH4 and SF6 and by hindgut CH4 production. In addition, the predicted CH4 emission rate appeared sensitive to factors that affect proportions of exhaled and eructed air sampled, i.e., eructation time fraction, exhalation time fraction, and distance from sampling point to mouth/nostrils. Changes in rumen fractional passage rate, eructation rate, SF6 release rate, background values and air sampling rate did not noticeably affect the predicted CH4 emission. Simulations with (13)CH4 as an alternative tracer show that the differences and sensitivity to parameters greatly disappear. The model is considered a useful tool to evaluate critical points in the SF6 technique. Data from in vivo experiments are needed to further evaluate model simulations. PMID:24625680

  1. Exhaled nitric oxide measure using multiple flows in clinically relevant subgroups of COPD

    Roberts, Nassim Bazeghi; Gerds, Thomas A; Budtz-Jørgensen, Esben;

    2011-01-01

    meaningful subgroups of COPD in a group of 91 COPD patients with FEV(1) 17-77% of predicted. Multiple flow rates FeNO at 10, 30, 50, 100 and 200 mL/s were measured and a two-compartment model was used to estimate the diffusion Capacity (D), alveolar NO concentration (Calv) and airway wall NO concentration...

  2. Quantification of volatile organic compounds in exhaled human breath. Acetonitrile as biomarker for passive smoking. Model for isoprene in human breath

    The topic of this thesis is the quantification of volatile organic compounds in human breath under various circumstances. The composition of exhaled breath reflects metabolic processes in the human body. Breath analysis is a non invasive technique which makes it most interesting especially for medical or toxicological applications. Measurements were done with Proton-Transfer-Reaction Mass-Spectrometry (PTR-MS). This technique combines the advantage of small fragmentation of chemical ionization with highly time resolved mass spectrometry. A big part of this work is about investigations of exposition due to tobacco smoke. After smoking cigarettes the initial increase and time dependence of some compounds in the human breath are monitored . The calculated decrease resulting only from breathing out the compounds is presented and compared to the measured decline in the breath. This allows the distinction whether breathing is the dominant loss of a compound or a different metabolic process remover it more efficiently. Acetonitrile measured in human breath is presented as a biomarker for exposition to tobacco smoke. Especially its use for quantification of passive smoking, the exposition to environmental tobacco smoke (ETS) is shown. The reached accuracy and the fast way of measuring of acetonitrile in human breath using PTR-MS offer a good alternative to common used biomarkers. Numerous publications have described measurements of breath isoprene in humans, and there has been a hope that breath isoprene analyses could be a non-invasive diagnostic tool to assess serum cholesterol levels or cholesterol synthesis rate. However, significant analytical problems in breath isoprene analysis and variability in isoprene levels with age, exercise, diet, etc. have limited the usefulness of these measurements. Here, we have applied proton-transfer-reaction mass spectrometry (PTR-MS) to this problem, allowing on-line detection of breath isoprene. We show that breath isoprene

  3. Exercise-Induced Changes in Exhaled NO Differentiates Asthma With or Without Fixed Airway Obstruction From COPD With Dynamic Hyperinflation

    Huang, Shu-Yi; Chou, Pai-Chien; Wang, Tsai-Yu; Lo, Yu-Lun; Joa, Wen-Ching; Chen, Li-Fei; Sheng, Te-Fang; Chung, Kian Fan; Wang, Chun-Hua; Kuo, Han-Pin

    2016-01-01

    Abstract Asthmatic patients with fixed airway obstruction (FAO) and patients with chronic obstructive pulmonary disease (COPD) share similarities in terms of irreversible pulmonary function impairment. Exhaled nitric oxide (eNO) has been documented as a marker of airway inflammation in asthma, but not in COPD. To examine whether the basal eNO level and the change after exercise may differentiate asthmatics with FAO from COPD, 27 normal subjects, 60 stable asthmatics, and 62 stable COPD patients were studied. Asthmatics with FAO (n = 29) were defined as showing a postbronchodilator FEV1/forced vital capacity (FVC) ≤70% and FEV1 less than 80% predicted after inhaled salbutamol (400 μg). COPD with dynamic hyperinflation (n = 31) was defined as a decrease in inspiratory capacity (ΔIC%) after a 6 minute walk test (6MWT). Basal levels of eNO were significantly higher in asthmatics and COPD patients compared to normal subjects. The changes in eNO after 6MWT were negatively correlated with the percent change in IC (r = −0.380, n = 29, P = 0.042) in asthmatics with FAO. Their levels of basal eNO correlated with the maximum mid-expiratory flow (MMEF % predicted) before and after 6MWT. In COPD patients with air-trapping, the percent change of eNO was positively correlated to ΔIC% (rs = 0.404, n = 31, P = 0.024). We conclude that asthma with FAO may represent residual inflammation in the airways, while dynamic hyperinflation in COPD may retain NO in the distal airspace. eNO changes after 6MWT may differentiate the subgroups of asthma or COPD patients and will help toward delivery of individualized therapy for airflow obstruction. PMID:27082615

  4. Expression of surfactant protein-A in exhaled breath condensate of patients with chronic obstructive pulmonary disease.

    Lin, Xue-Feng; Zhang, Lei; Shi, Shu-Yuan; Fan, Yi-Chu; Wu, Zhen-Lin; Zhang, Xun; Sun, Da-Qiang

    2016-02-01

    Pulmonary surfactant protein A (SP-A) has been associated with host defense in the lung, and contributes to the pathogenesis of chronic obstructive pulmonary disease (COPD). The present study aimed to determine a non‑invasive method of measurement of SP‑A, and further examine the expression levels of SP‑A in patients with COPD. SP‑A was detected in the exhaled breath condensate (EBC) obtained from patients with COPD and from non‑COPD subjects. The individuals recruited for the present study comprised 60 subjects with and without COPD, who underwent lobectomy for a solitary peripheral lung nodule. EBC was collected using a condenser, and an enzyme‑linked immunosorbent assay (ELISA) was used to measure the levels of SP‑A. Tissue samples were obtained during lobectomy through resection of the adjacent lung tissues, located >5 cm from the nodule. Western blot analysis and immunohistochemistry were used to measure SP‑A and SP‑A‑positive type II pneumocytes. The results demonstrated that SP‑A was detectable in the EBC of all subjects. The results of the ELISA and western blotting demonstrated that the expression levels of SP‑A were significantly decreased in patients with COPD, compared with the non‑COPD subjects. The reduction of SP‑A‑positive type II pneumocytes was associated with the expression levels of SP‑A. Decreased expression levels of SP‑A in EBC were associated with a higher degree of airway limitation. These results suggested that the measurement of SP‑A levels in the EBC may serve as a method for monitoring airway obstruction in patients with COPD. Further investigations are required in order to examine these observations further and to elucidate the underlying mechanisms. PMID:26707652

  5. Comparison of exhaled carbon monoxide levels among commuters and roadside vendors in an urban and a suburban population in Pakistan.

    Sabzwari, Saniya R; Fatmi, Zafar

    2011-09-01

    Carbon monoxide (CO) is one of the six criteria air pollutants related to urbanization and has a wide range of health effects. The study measured and compared the exhaled CO levels among commuters and roadside vendors in potentially heavy and low traffic volume areas of Karachi, a megacity in Pakistan. Saddar town [areas of M. A. Jinnah Road (Tibet Center, Denso Hall) and Empress Market] was selected to represent an area of high traffic volume and the suburban town of Gadap (Gadap and Gulshan-e-Maymar) was selected to represent an area of no or low traffic volume. The study compared the CO exposure of commuters and roadside vendors in high and low traffic volume in Karachi. CO exposure was measured in expired air using the breath analyzer module of Bacharach Monoxor-II, USA. A total of 326 individuals (115 commuters and 211 stationary roadside vendors) from Saddar town (n = 193) and Gadap town (n = 133) were selected. In addition, CO levels in ambient air in the same areas, using portable CO analyzer (Bacharach, Monoxor-II, USA), were measured. The mean ambient CO level at Saddar town was 15.6 (SE ± 2.6) ppm compared to 3.3 (SE ± 0.3) ppm at Gadap town. The mean CO level in expired air was significantly higher among nonsmokers at Saddar town (12.8 ± 0.5 ppm) compared to the nonsmokers at Gadap town (7.8 ± 0.4 ppm). The mean CO level in expired air among smokers was twice that of nonsmokers (21.6 vs. 10.6 ppm). CO in expired air was greater among high traffic volume commuters and roadside stationary population in Karachi, Pakistan. The population in Karachi is exposed to high concentration of air pollutants. These pollutants need to be characterized for health effects and interventions needs to be developed. PMID:21120689

  6. Effect of age and eosinophil number on fractional exhaled nitric oxide level in non-asthmatic children in shanghai.

    Wei Liu

    2014-10-01

    Full Text Available This study aimed to identify the relationship between fractional exhaled nitric oxide (FeNO level and potential factors in non-asthmatic children from Shanghai, China. From March to April 2012, the school-aged children fulfilling the inclusion criteria were recruited. The FeNO levels of non-asthmatic children were detected by the Nano Coulomb nitric oxide analyzer. Questionnaires were recorded, including personal data, family illness history and daily habits. In addition, not only the number of leukocytes and eosinophils but also the level of hemoglobin in peripheral blood, were measured via the automated blood cell analyzer. All data were statistically analyzed with SPSS version 17.0 software and the correlation of these potential factors with FeNO level was calculated via Kendall's rank correlation. A total of 132 healthy children (aging 6-13 years were enrolled in Minhang District, Shanghai, China. The mean value of FeNO level was 15.05 ppb. The correlation analyses revealed that age (R=0.190, p=0.029 and eosinophil number (R=0.575, p=0.000 were significantly and positively correlated with FeNO levels. The FeNO levels of individuals aged 10-13 years was significantly higher than those of the individuals aged 6-9 years (22.65 ± 18.82 ppb vs. 15.28 ± 9.78 ppb, p<0.05. However, other potential factors were not significantly correlated with FeNO level. The FeNO levels in healthy school-aged children may reflect airway eosinophilic inflammation levels, and was affected by eosinophil count and age significantly.

  7. Comparison of exhaled breath condensate pH using two commercially available devices in healthy controls, asthma and COPD patients

    Vogelmeier Claus

    2009-08-01

    Full Text Available Abstract Background Analysis of exhaled breath condensate (EBC is a non-invasive method for studying the acidity (pH of airway secretions in patients with inflammatory lung diseases. Aim To assess the reproducibility of EBC pH for two commercially available devices (portable RTube and non-portable ECoScreen in healthy controls, patients with asthma or COPD, and subjects suffering from an acute cold with lower-airway symptoms. In addition, we assessed the repeatability in healthy controls. Methods EBC was collected from 40 subjects (n = 10 in each of the above groups using RTube and ECoScreen. EBC was collected from controls on two separate occasions within 5 days. pH in EBC was assessed after degasification with argon for 20 min. Results In controls, pH-measurements in EBC collected by RTube or ECoScreen showed no significant difference between devices (p = 0.754 or between days (repeatability coefficient RTube: 0.47; ECoScreen: 0.42 of collection. A comparison between EBC pH collected by the two devices in asthma, COPD and cold patients also showed good reproducibility. No differences in pH values were observed between controls (mean pH 8.27; RTube and patients with COPD (pH 7.97 or asthma (pH 8.20, but lower values were found using both devices in patients with a cold (pH 7.56; RTube, p Conclusion We conclude that pH measurements in EBC collected by RTube and ECoScreen are repeatable and reproducible in healthy controls, and are reproducible and comparable in healthy controls, COPD and asthma patients, and subjects with a common cold.

  8. Exercise-Induced Changes in Exhaled NO Differentiates Asthma With or Without Fixed Airway Obstruction From COPD With Dynamic Hyperinflation.

    Huang, Shu-Yi; Chou, Pai-Chien; Wang, Tsai-Yu; Lo, Yu-Lun; Joa, Wen-Ching; Chen, Li-Fei; Sheng, Te-Fang; Chung, Kian Fan; Wang, Chun-Hua; Kuo, Han-Pin

    2016-04-01

    Asthmatic patients with fixed airway obstruction (FAO) and patients with chronic obstructive pulmonary disease (COPD) share similarities in terms of irreversible pulmonary function impairment. Exhaled nitric oxide (eNO) has been documented as a marker of airway inflammation in asthma, but not in COPD. To examine whether the basal eNO level and the change after exercise may differentiate asthmatics with FAO from COPD, 27 normal subjects, 60 stable asthmatics, and 62 stable COPD patients were studied. Asthmatics with FAO (n = 29) were defined as showing a postbronchodilator FEV1/forced vital capacity (FVC) ≤70% and FEV1 less than 80% predicted after inhaled salbutamol (400 μg). COPD with dynamic hyperinflation (n = 31) was defined as a decrease in inspiratory capacity (ΔIC%) after a 6 minute walk test (6MWT). Basal levels of eNO were significantly higher in asthmatics and COPD patients compared to normal subjects. The changes in eNO after 6MWT were negatively correlated with the percent change in IC (r = -0.380, n = 29, P = 0.042) in asthmatics with FAO. Their levels of basal eNO correlated with the maximum mid-expiratory flow (MMEF % predicted) before and after 6MWT. In COPD patients with air-trapping, the percent change of eNO was positively correlated to ΔIC% (rs = 0.404, n = 31, P = 0.024). We conclude that asthma with FAO may represent residual inflammation in the airways, while dynamic hyperinflation in COPD may retain NO in the distal airspace. eNO changes after 6MWT may differentiate the subgroups of asthma or COPD patients and will help toward delivery of individualized therapy for airflow obstruction. PMID:27082615

  9. Chemical characterization of exhaled breath to differentiate between patients with malignant plueral mesothelioma from subjects with similar professional asbestos exposure

    Gennaro, G. de; Longobardi, F.; Stallone, G.; Trizio, L.; Tutino, M. [University of Bari Aldo Moro, Department of Chemistry, Bari (Italy); Dragonieri, S. [University of Bari Aldo Moro, Department of Pulmonology, Bari (Italy); Musti, M. [University of Bari Aldo Moro, Department of Occupational Medicine, Bari (Italy)

    2010-12-15

    Malignant pleural mesothelioma (MPM) is an aggressive tumour whose main aetiology is the long-term exposure to asbestos fibres. The diagnostic procedure of MPM is difficult and often requires invasive approaches; therefore, it is clinically important to find accurate markers for MPM by new noninvasive methods that may facilitate the diagnostic process and identify patients at an earlier stage. In the present study, the exhaled breath of 13 patients with histology-established diagnosis of MPM, 13 subjects with long-term certified professional exposure to asbestos (EXP) and 13 healthy subjects without exposure to asbestos (healthy controls, HC) were analysed. An analytical procedure to determine volatile organic compounds by sampling of air on a bed of solid sorbent and thermal desorption GC-MS analysis was developed in order to identify the compounds capable of discriminating among the three groups. The application of univariate (ANOVA) and multivariate statistical treatments (PCA, DFA and CP-ANN) showed that cyclopentane and cyclohexane were the dominant variables able to discriminate among the three groups. In particular, it was found that cyclohexane is the only compound able to differentiate the MPM group from the other two; therefore, it can be a possible marker of MPM. Cyclopentane is the dominant compound in the discrimination between EXP and the other groups (MPM and HC); then, it can be considered a good indicator for long-term asbestos exposure. This result suggests the need to perform frequent and thorough investigations on people exposed to asbestos in order to constantly monitor their state of health or possibly to study the evolution of disease over time. (orig.)

  10. The use of the exhaled Thoron activity measurement system in the field of radiological labor hygiene of NORM and its future

    The purpose of this paper is to present a brief description of the basic characteristics of an exhaled thoron measurement system and its use in the study of the health effects and its protection measures of the miners inhaled thorium dusts in the Bayun Obo Iron Mine in recent twenty years. The method we used is to measure the thorium lung burden of each miner by using an exhaled thoron activity measurement system. An epidemiological study of lung cancer mortality, physical examination (including peripheral blood counts, hepatic function test, X-ray radiograph, lung function test) of each miner were also carried out. Results showed that the relationship between the thorium lung burden and it health effects were obtained. It was the first time that we found if any miner.s thorium lung burden not higher than 11.11 Bq, his peripheral blood counts and hepatic functions will not be affected. It was also the first time that we found if any miners. thorium-containing lung burden reached a value of 755 mg, 0+ stage pneumoconiosis would be suffered. It is concluded that the exhaled thoron activity measurement system could be used in monitoring the thorium lung burden of the workers inhaling thorium-containing dusts at any thorium dust generating factories; in monitoring the thorium contamination of the inhabitants living around the thorium dust generating factories; in judging the efficiency of agents using in accelerating the excretion of thorium compounds from the human body; in preventing the thorium dust exposed miners suffered from the pneumoconiosis; in monitoring the thorium contamination in the lung of the staffs and workers working at the different spots of the cycle of thorium nuclear reactor development. (author)

  11. Nitric oxide in exhaled and aspirated nasal air as an objective measure of human response to isopropanol oxidation products and pthtalate esters in indoor air

    Lagercrantz, Love Per; Famula, Basia; Sundell, Jan

    exposed to 2 commonly occurring indoor air pollutants and to a clean reference condition for 4.5 hours. Assessments of the environment were obtained using questionnaires. The polluted conditions were perceived as worse than the reference condition. After exposure to the two polluted conditions a small......The use of Nitric Oxide (NO) concentration in exhaled and aspirated nasal air to assess human response to indoor air pollution was tested in a climate chamber exposure experiment. The concentration of NO was measured using a chemiluminescence NO analyser. Sixteen healthy female subjects were...... polluted indoor air and sub-clinical inflammation....

  12. Assessment of health effects related to fiber glass exposure in fiber glass workers: exhaled biomarkers eCO, FENO and their usefulness in the occupational environment testing

    2013-01-01

    Introduction Numerous epidemiological animal model studies have been conducted in order to assess the health effects of man-made vitreous fibers. They have been shown to be responsible for producing lung fibrosis and lung and peritoneal cancer in animal models. A few large cohort studies were conducted in Europe and the US to assess the health effects of fiber glass in production workers and a higher cancer incidence was evidenced. Aim The aim of the study is to assess the usefulness of exhal...

  13. A theoretical study on accurate measurements of thoron with airflow-through scintillation cell method

    For accurate measurements of 220Rn concentration with airflow-through scintillation cell method, a theoretical study was performed for discussing the influences of sampling flow rate, volumes of sampling tube and scintillation cell on the measurements. It is found that a high flow rate and a large inner volume of scintillation cell as well as a small inner volume of sampling tube are not only preferable for measuring low levels of 220Rn, but also helpful for enhancing the measurement accuracy. In calibration experiments, both the sampling flow rate and the sampling tube volume should be noted. The variations of the flow rate and tube volume should be considered for accurate measurements in the fields. (authors)

  14. Diagnosing asthma in general practice with portable exhaled nitric oxide measurement – results of a prospective diagnostic study

    Laux Gunter

    2009-03-01

    Full Text Available Abstract Background To evaluate the sensitivity, specificity and predictive values of fractional exhaled nitric oxide (FENO for the diagnosis of asthma in general practice. Methods Prospective diagnostic study with 160 patients attending 10 general practices for the first time with complaints suspicious of obstructive airway disease (OAD. Patients were referred to a lung function laboratory for diagnostic investigation. The index test was FENO measured with a portable FENO analyser based on electrochemical sensor. The reference standard was the Tiffeneau ratio (FEV1/VC as received by spirometric manoeuvre and/or results of bronchial provocation. Bronchial provocation with methacholine was performed to determine bronchial hyper-responsiveness (BHR in the event of inconclusive spirometric results. Results 88 (55% were female; their average age was 43.9 years. 75 (46.9% patients had asthma, 25 (15.6% had COPD, 8 (5.0% had an overlap of COPD and asthma, and 52 (32.5% had no OAD. At a cut-off level of 46 parts per billion (ppb (n = 30; 18.8%, sensitivity was 32% (95%CI 23–43%, specificity 93% (95%CI 85–97%, positive predictive value (PPV 80% (95%CI 63–91%, negative predictive value (NPV 61% (95%CI 52–69% when compared with a 20% fall in FEV1 from the baseline value (PC20 after inhaling methacholine concentration ≤ 16 mg/ml. At 76 ppb (n = 11; 6.9% specificity was 100% (95%CI 96–100% and PPV was 100% (95%CI 72–100. At a cut-off level of 12 ppb (n = 34; 21.3%, sensitivity was 90% (95%CI 79–95%, specificity 25% (95%CI 17–34%, PPV 40% (95%CI 32–50, NPV 81% (95%CI 64–91% when compared with a 20% fall of FEV1 after inhaling methacholine concentration ≤ 4 mg/ml. Three patients with unsuspicious spirometric results have to be tested with FENO to save one bronchial provocation test. Conclusion Asthma could be ruled in with FENO > 46 ppb. Mild and moderate to severe asthma could be ruled out with FENO ≤ 12 ppb. FENO measurement with

  15. Clinical trial on the efficacy of exhaled carbon monoxide measurement in smoking cessation in primary health care

    Ripoll Joana

    2012-07-01

    Full Text Available Abstract Background Smoking cessation is beneficial for our health at any point in life, both in healthy people and in people already suffering from a smoking-related disease. Any help to quit smoking can produce considerable benefits for Public Health. The purpose of the present study is to evaluate the efficacy of the CO-oximetry technique together with brief advice in smoking cessation, in terms of reduction of the number of cigarettes or in the variation of the motivation to quit smoking at month 12 compared with brief advice alone. Methods/Design Randomised, parallel, single-blind clinical trial in a primary health care setting in Majorca (Spain. Smokers in contemplation or pre-contemplation phase will be included in the study. Exclusion criteria: Smokers in preparation phase, subjects with a terminal illness or whose health status does not allow them to understand the study or complete the informed consent, and pregnant or breastfeeding women. The subjects will be randomly assigned to the control group (CG or the intervention group (IG. The CG will receive brief advice, and the IG will receive brief advice together with a measurement of exhaled CO. There will be follow-up evaluations at 6 and 12 months after inclusion. 471 subjects will be needed per group in order to detect a difference between groups ≥ 5%. Primary outcome: sustained smoking cessation (at 6 and 12 months confirmed by urine cotinine test. Secondary outcomes: point smoking cessation at 6 and 12 months both confirmed by urine cotinine analysis and self-reported, reduction in cigarette consumption, and variation in phase of smoking cessation. Discussion CO-oximetry is an inexpensive, non-invasive, fast technique that requires little technical training; making it a technique for risk assessment in smokers that can be easily applied in primary care and, if proven effective, could serve as a reinforcement aid in smoking cessation intervention activities. Trial

  16. Relation between biomarkers in exhaled breath condensate and internal exposure to metals from gas metal arc welding.

    Hoffmeyer, Frank; Raulf-Heimsoth, Monika; Weiss, Tobias; Lehnert, Martin; Gawrych, Katarzyna; Kendzia, Benjamin; Harth, Volker; Henry, Jana; Pesch, Beate; Brüning, Thomas

    2012-06-01

    Concerning possible harmful components of welding fumes, besides gases and quantitative aspects of the respirable welding fumes, particle-inherent metal toxicity has to be considered.The objective of this study was to investigate the effect markers leukotriene B4 (LTB4),prostaglandin E2 (PGE2) and 8-isoprostane (8-Iso PGF2α) as well as the acid–base balance(pH) in exhaled breath condensate (EBC) of 43 full-time gas metal arc welders (20 smokers) in relation to welding fume exposure. We observed different patterns of iron, chromium and nickel in respirable welding fumes and EBC. Welders with undetectable chromium in EBC(group A, n = 24) presented high iron and nickel concentrations. In this group, higher 8-isoPGF2α and LTB4 concentrations could be revealed compared to welders with detectable chromium and low levels of both iron and nickel in EBC (group B): 8-iso PGF2α443.3 pg mL−1 versus 247.2 pg mL−1; p = 0.001 and LTB4 30.5 pg mL−1 versus 17.3 pgmL−1; p = 0.016. EBC-pH was more acid in samples of group B (6.52 versus 6.82; p = 0.011).Overall, effect markers in welders were associated with iron concentrations in EBC according to smoking habits--non-smokers/smokers: LTB4 (rs = 0.48; p = 0.02/rs = 0.21; p = 0.37),PGE2 (rs = 0.15; p = 0.59/rs = 0.47; p = 0.07), 8-iso PGF2α (rs = 0.18; p = 0.54/rs = 0.59;p = 0.06). Sampling of EBC in occupational research provides a matrix for the simultaneous monitoring of metal exposure and effects on target level. Our results suggest irritative effects in the airways of healthy welders. Further studies are necessary to assess whether these individual results might be used to identify welders at elevated risk for developing a respiratory disease. PMID:22622358

  17. [Value of Fractional Exhaled Nitric Oxide after Using a Beta-2 Bronchodilator in the Differential Diagnosis of Bronchial Asthma and Chronic Obstructive Pulmonary Disease].

    Ura, Midori; Tanaka, Hitomi; Takahashi, Kaori; Yamazaki, Haruna; Fujimoto, Keisaku

    2016-02-01

    It has been established that an increase in fractional exhaled nitric oxide (FeNO) is one of the indicators of bronchial asthma (BA) in clinical settings. However, the differential diagnosis of BA and chronic obstructive pulmonary disease (COPD) is difficult due to pathological similarities. Therefore, to determine if FeNO may be utilized in the differential diagnosis of BA and COPD, we compared FeNO values before and after inhalation of a short-acting beta-2 agonist (SABA). There were 3 groups of subjects recruited to this study: (1) 23 normal healthy controls, (2) 36 patients with BA, and (3) 13 patients with COPD. We measured FeNO, forced vital capacity, forced expiratory volume in 1 second (FEV1), and FEV1%, calculated using spirometry. Then, after the subjects inhaled the SABA, we measured these data after 10 and 30 minutes. Here we found that after inhalation of a SABA, 8 cases in the BA group who showed reversibility of airway obstruction demonstrated significantly increased FeNO values compared to the BA patients with non-reversible airway obstruction, those with COPD, and healthy subjects. This finding may be because the obstructed pulmonary peripheral airway was expanded by inhaling a SABA, and nitric oxide, which had been produced in the peripheral airway, was then exhaled. These results suggest the possibility that FeNO may be utilized in the differential diagnosis of BA and COPD. PMID:27311275

  18. Investigations of the enterohepatic bile salt circulation using the 14C-glycol cholate/14CO2 exhalation test in persons with Billroth-II stomach resection

    A 14C-glycol cholate/14CO2 exhalation test was carried out in 34 normal persons, 32 persons with a Billroth-II resection stomach, and 9 patients with a Billroth-II resection stomach and gastroenterological disorders. Persons with a normal stomach function after B-II resection and an objective lack of symptoms of a gastroenterological disease had normal test results in all cases. In 7 of the 9 B-II resected patients with various disorders or diseases of the intestinal tract of the liver gallbladder on pancreas, 14CO2 exhalation was pathologically increased. In agreement with the hypothesis that deconjugation of bile salts can only be caused by bacterial enzymes, a pathological finding can be explained by a pathological bacteria population in the upper intestinal tract or by a loss of bile salts. However, the clinical importance of pathological test results remains doubtful as 3 out of the 7 patients with pathological results presented with no clinical symptoms. (orig.)

  19. RESPIRATORY FUNCTION RECOVERY OF THE POSTSURGICAL PATIENTS BY MEANS OF THE BIOFEEDBACK OF THE CARBON DIOXIDE CONCENTRATION IN EXHALED AIR AND RESPIRATORY RATE

    N. G. Brazovskaya; Ye. V. Melekhin; M V Svetlik; K. S. Brazovsky; A. N. Vusik

    2016-01-01

    The methodical, technical and software realization of the biofeedback of expiration parameters are described. The biofeedback training method based on the breath frequency and CO2  concentration regulation is proposed. Preliminary study was conducted in the group of patients after abdominal surgical. It has been shown that the patients master their skills of CO2  concentration self-regulation. Using biofeedback for the postsurgical rehabilitation facilitates the rapid recovery of the expirati...

  20. RESPIRATORY FUNCTION RECOVERY OF THE POSTSURGICAL PATIENTS BY MEANS OF THE BIOFEEDBACK OF THE CARBON DIOXIDE CONCENTRATION IN EXHALED AIR AND RESPIRATORY RATE

    N. G. Brazovskaya

    2016-01-01

    Full Text Available The methodical, technical and software realization of the biofeedback of expiration parameters are described. The biofeedback training method based on the breath frequency and CO2  concentration regulation is proposed. Preliminary study was conducted in the group of patients after abdominal surgical. It has been shown that the patients master their skills of CO2  concentration self-regulation. Using biofeedback for the postsurgical rehabilitation facilitates the rapid recovery of the expiration parameters.

  1. Persistence of aroma volatiles in the oral and nasal cavities: real-time monitoring of decay rate in air exhaled through the nose and mouth.

    Sánchez-López, José Antonio; Ziere, Aldo; Martins, Sara I F S; Zimmermann, Ralf; Yeretzian, Chahan

    2016-01-01

    The persistence of aroma compounds in breath after swallowing is an important attribute of the overall aroma experience during eating and drinking. It is mainly related to the coating of the oral tract with food residues and the interaction between volatile compounds and airway mucosa. We have studied the persistence of eight compounds (2,5-dimethylpyrazine, guaiacol, 4-methylguaiacol, phenylethylalcohol, ethylbutanoate, ethyloctanoate, isoamylacetate and 2-heptanone) both in-nose and in-mouth after administration of volatiles in gas phase (vapor) to five different panelists. By using volatiles in the gas phase, only the interaction with the mucosa is highlighted and the formation of a liquid coating in the oral and tracheal airway is avoided. The physicochemical properties of the compounds, mainly polarity and vapor pressure, determine the interactions of the volatiles with the airway mucosa. The use of different breathing protocols allowed the study of the differences between nasal and oral mucosa in volatile retention, with higher persistence of volatiles obtained in-mouth. Initial concentration also affected persistence, but only for compounds with high volatility and at low concentration. PMID:27380868

  2. Dose-dependent relationship between prenatal exposure to fine particulates and exhaled carbon monoxide in non-asthmatic children. A population-based birth cohort study

    Wiesław A. Jędrychowski

    2013-02-01

    Full Text Available Objectives: The main goal of the study was to assess possible association between fetal exposure to fi ne particulate matter (PM2.5 and exhaled carbon monoxide (eCO measured in non-asthmatic children. Material and Methods: The subjects include 118 children taking part in an ongoing population-based birth cohort study in Kraków. Personal samplers of PM2.5 were used to measure fi ne particle mass in the fetal period and carbon monoxide (CO in exhaled breath from a single exhalation effort at the age of 7. In the statistical analysis of the effect of prenatal PM2.5 exposure on eCO, a set of potential confounders, such as environmental tobacco smoke (ETS, city residence area, sensitization to house dust allergens and the occurrence of respiratory symptoms monitored over the seven-year follow-up was considered. Results: The level of eCO did not correlate with the self-reported ETS exposure recorded over the follow-up, however, there was a positive signifi cant relationship with the prenatal PM2.5 exposure (non-parametric trend p = 0.042. The eCO mean level was higher in atopic children (geometric mean = 2.06 ppm, 95% CI: 1.58–2.66 ppm than in non-atopic ones (geometric mean = 1.57 ppm, 95% CI: 1.47–1.73 ppm and the difference was statistically signifi cant (p = 0.036. As for the respiratory symptoms, eCO values were associated positively only with the cough severity score recorded in the follow-up (nonparametric trend p = 0.057. In the nested multivariable linear regression model, only the effects of prenatal PM2.5 and cough severity recorded in the follow-up were related to eCO level. The prenatal PM2.5 exposure represented 5.1%, while children’s cough represented only 2.6% of the eCO variability. Conclusion: Our study suggests that elevated eCO in non-asthmatic children may result from oxidative stress experienced in the fetal period and that heme oxygenase (HO activity in body tissues may be programmed in the fetal period by the exposure to

  3. Air Change Rates and Radon Concentrations in Residential Protected Rooms

    According to national regulations, every Israeli dwelling must include a Residential Protected Room (RPR), which is intended for shelter against artillery threats and protection from chemical or biological gases. These rooms are multi-purpose, but must be equipped with only one window of limited size and one entrance door, both extremely airtight. The door is required to open out of the room. Another regular (inward opening and less tight) door may be added on the same frame and serve the everyday functions. The tight window cannot be replaced nor can a less tight window be added. The entire envelope (walls and slabs) of the RPR must be made of 20-25 cm thick reinforced concrete. Due to economic and environmental reasons there is an increased tendency to use recycled industrial by-products containing Technologically Enhanced Natural Occurring Radioactive Materials (TENORM) in the building material industry. Fly ash (FA), produced as a by-product in the combustion of coal, is extensively used in Israel since the early 1990's in concrete and as an additive to cement. The increase of 226Ra activity concentration, the mineralogical characteristics of the FA and of the concrete may affect the radon exhalation rate and consequently the radon exposure in RPRs. In addition, due to its special features, the RPR is expected to experience, under regular use conditions, a lower air change rate than any of the other rooms in the dwelling. Consequently, concern was raised with regard to long term radon exposure in RPRs. The paper presents results derived in a research project that studied in-situ air change rates and radon concentration evolution under various ventilation scenarios in 6 RPRs in a high-rise building, and compared evaluated free radon exhalation rates from the walls with values derived from laboratory samples of the same concretes

  4. “白烟型”热液喷流岩研究进展%Progress of Research on "White Smoke Type"Exhalative Hydrothermal Rocks

    焦鑫; 柳益群; 周鼎武; 汪双双; 南云; 周宁超; 杨焱钧

    2013-01-01

    The " black smoker" hydrothermal activities in the bottom of the sea/lake and its related diagene-sis, mineralization and paleontology, which are mentioned in both modern and historical geology, have become a hotspot in the multi-disciplinary study nowadays. But comparatively speaking, the relative research on " white smoke type" exhalative hydrothermal rocks is obviously inadequate. Based on reading a large number of domestic and foreign literatures, combined theory with authors' practical research work, this paper reviews the historic and present situation of the study of exhalative hydrothermal rocks. In this article, the authors put emphasis on introducing the progress on the origin of dolomite, as a symbolic low-temperature hydrothermal mineral. The authors believe that the "white smoke type" exhalative hydrothermal dolostone is the typical sample of primary dolostone. A-vailable information indicates that the layers of "white smoke type" exhalative rocks which has been reported, that is, Xiagou Formation in Jiuxi basin and Lucaogou Formation in Santanghu basin, are important hydrocarbon source rock in their respective regions. According to this information, the following issues are worthy to be taken into consideration.①The special environment of the hydrothermal activities and their related thermophilic bacteria and food chain makes the organic matter, which could provide material basis for the generation of oil and gas, enriched. ② Mantle-originated material is likely to bring mantle-originated hydrocarbons. ③Hydrothermal activities would increase the geotemperature of sedimentary basin generally, as a result, it may accelerate the maturity of hydrocarbon source rocks. Lastly, the authors give their questions and proposals for further research in this field.%现代和地质历史中的海底、湖底的“黑烟囱型”热液活动及相关成岩、成矿和古生物活动已成为当今多学科的研究热点,而与“白烟型”热液喷流岩

  5. Method for parameter-free determination of Radon exhalation and dimensioning of sealing cover in the remediation of residues of mining sites

    Alternative methods for assessing the protective effect of liners against radon emissions, with the focus on the radon decay product Pb-210. The so-called 'lead track' was used, i.e. the difference of the specific activities of Pb-210 and Ra-226. With a half-life of 22.3 years, Pb-210 is well suited for assessing long-term effects of radon transport by measuring its specific activity in soil samples. Especially measurements of the depth-dependent Pb-210 concentration profiles resp. the lead track in soils and liners provided information on exhalation of radon or radon concentrations in soil air, which reflect the transport patterns over periods of more than 30 years. (orig.)

  6. Asthma-COPD Overlap Syndrome (ACOS): Single disease entity or not? Could exhaled nitric oxide be a useful biomarker for the differentiation of ACOS, asthma and COPD?

    Karampitsakos, Theodoros; Gourgoulianis, Konstantinos I

    2016-06-01

    Asthma and chronic obstructive pulmonary disease (COPD) represent two major public health problems. However, there is a significant proportion of patients with a mixed asthma-COPD phenotype. This condition is defined as asthma-COPD overlap syndrome (ACOS). Since there are no internationally accepted criteria for the diagnosis of that syndrome, its management remains difficult. Given the fact that patients with ACOS have an increased risk of exacerbation and hospitalization, there is a pressing need for a more targeted approach and better management. We propose that fractional exhaled nitric oxide (FeNO), a marker of eosinophilic inflammation, could help clinicians differentiate ACOS from asthma and COPD. We evaluate this hypothesis, using data derived from the existing literature. PMID:27142135

  7. Inhaled corticosteroids do not reduce initial high activity of matrix metalloproteinase (MMP)-9 in exhaled breath condensates of children with asthma exacerbation: a proof of concept study

    Grzela, Katarzyna; Zagórska, Wioletta; Krejner, Alicja; Banaszkiewicz, Aleksandra; Litwiniuk, Małgorzata; Kulus, Marek

    2016-01-01

    Inhaled corticosteroids (ICS) are the key component of asthma treatment. However, it is unclear whether they could control the activity and level of matrix metalloproteinase (MMP)-9, which is an important factor in asthma-associated inflammation and airway remodeling. Therefore, the aim of this proof of concept study was to analyze the influence of increased doses of ICS on MMP-9 in exhaled breath condensates (EBC) of patients with allergic asthma exacerbation. Apart from MMP-9, the assessment concerned selected inflammation markers – exhaled nitric oxide (eNO) and cytokines (IL-8 and TNF). The study involved a small group (n = 4) of individuals with asthma exacerbation. The intervention concerned increased doses of ICS with β-mimetics for 4 weeks. In addition to clinical evaluation, eNO measurements and EBC collections were done before and after 4 weeks of intense ICS treatment. The biochemical assessment of EBC concerned MMP-9, IL-8 and TNF. The data were compared to results of healthy controls (n = 6). The initial levels of eNO, MMP-9 and TNF in EBC were higher in the asthma group than in controls. In all subjects IL-8 levels were below the detection limit. After 4 weeks of ICS treatment in all patients we observed improvement of clinical and laboratory parameters. Interestingly, despite reduction of eNO and TNF, the activity of MMP-9/EBC remained on the initial level. Practical relevance of our results is limited by a small group. Nevertheless, our data suggest that ICS, although sufficient to control symptoms and inflammatory markers, may be ineffective to reduce MMP-9/EBC activity in asthma exacerbation and, possibly, airway remodeling. PMID:27536209

  8. A simple breathing rate-sensing method exploiting a temporarily condensed water layer formed on an oxidized surface

    Seo, Min-Ho; Yang, Hyun-Ho; Choi, Kwang-Wook; Lee, Jae-Shin; Yoon, Jun-Bo

    2015-02-01

    We describe a very simple breathing rate-sensing method that detects a significant electric current change between two metal electrodes on an oxidized surface. The current change is caused by the formation of a water layer from exhaled breath. We discovered that breathing onto the oxidized surface causes instant water condensation, and it generates 20 times increased current than that measured in the inhalation period. The condensed water quickly evaporates, enabling us to detect dynamic human breathing in real time. We also investigated the breathing rate sensor by varying the relative humidity, temperature, and breathing frequency and confirmed its potential for practical applications.

  9. Exhaled breath condensate collection for nitrite dosage: a safe and low cost adaptation Coleta do condensado do ar exalado pulmonar para a dosagem de nitrito: Uma adaptação segura e barata

    Graziela Saraiva Reis; Viviane dos Santos Augusto; Maria Eliza Jordani de Souza; Caroline Floreoto Baldo; Alfredo José Rodrigues; Paulo Roberto Barbosa Evora

    2010-01-01

    PURPOSE: Standardization of a simple and low cost technique of exhaled breath condensate (EBC) collection to measure nitrite. METHODS: Two devices were mounted in polystyrene boxes filled either with crushed ice/salt crystals or dry ice/crushed ice. Blood samples were stored at -70º C for posterior nitrite dosages by chemiluminescence and the Griess reaction. RESULTS: a) The use of crushed ice/dry ice or salt revealed sufficient EBC room air collection, but was not efficient for patients unde...

  10. The effect of dose, dose rate, route of administration, and species on tissue and blood levels of benzene metabolites.

    Henderson, R F; Sabourin, P J; Bechtold, W E; Griffith, W. C.; Medinsky, M A; Birnbaum, L S; Lucier, G W

    1989-01-01

    Studies were completed in F344/N rats and B6C3F1 mice to determine the effect of dose, dose rate, route of administration, and rodent species on formation of total and individual benzene metabolites. Oral doses of 50 mg/kg or higher saturated the capacity for benzene metabolism in both rats and mice, resulting in an increased proportion of the administered dose being exhaled as benzene. The saturating air concentration for benzene metabolism during 6-hr exposures was between 130 and 900 ppm. ...

  11. Humidity Testing for Human Rated Spacecraft

    Johnson, Gary B.

    2009-01-01

    Determination that equipment can operate in and survive exposure to the humidity environments unique to human rated spacecraft presents widely varying challenges. Equipment may need to operate in habitable volumes where the atmosphere contains perspiration, exhalation, and residual moisture. Equipment located outside the pressurized volumes may be exposed to repetitive diurnal cycles that may result in moisture absorption and/or condensation. Equipment may be thermally affected by conduction to coldplate or structure, by forced or ambient air convection (hot/cold or wet/dry), or by radiation to space through windows or hatches. The equipment s on/off state also contributes to the equipment s susceptibility to humidity. Like-equipment is sometimes used in more than one location and under varying operational modes. Due to these challenges, developing a test scenario that bounds all physical, environmental and operational modes for both pressurized and unpressurized volumes requires an integrated assessment to determine the "worst-case combined conditions." Such an assessment was performed for the Constellation program, considering all of the aforementioned variables; and a test profile was developed based on approximately 300 variable combinations. The test profile has been vetted by several subject matter experts and partially validated by testing. Final testing to determine the efficacy of the test profile on actual space hardware is in the planning stages. When validation is completed, the test profile will be formally incorporated into NASA document CxP 30036, "Constellation Environmental Qualification and Acceptance Testing Requirements (CEQATR)."

  12. Motion-compensated PET image reconstruction with respiratory-matched attenuation correction using two low-dose inhale and exhale CT images

    Positron emission tomography (PET) is widely used for diagnosis and follow up assessment of radiotherapy. However, thoracic and abdominal PET suffers from false staging and incorrect quantification of the radioactive uptake of lesion(s) due to respiratory motion. Furthermore, respiratory motion-induced mismatch between a computed tomography (CT) attenuation map and PET data often leads to significant artifacts in the reconstructed PET image. To solve these problems, we propose a unified framework for respiratory-matched attenuation correction and motion compensation of respiratory-gated PET. For the attenuation correction, the proposed algorithm manipulates a 4D CT image virtually generated from two low-dose inhale and exhale CT images, rather than a real 4D CT image which significantly increases the radiation burden on a patient. It also utilizes CT-driven motion fields for motion compensation. To realize the proposed algorithm, we propose an improved region-based approach for non-rigid registration between body CT images, and we suggest a selection scheme of 3D CT images that are respiratory-matched to each respiratory-gated sinogram. In this work, the proposed algorithm was evaluated qualitatively and quantitatively by using patient datasets including lung and/or liver lesion(s). Experimental results show that the method can provide much clearer organ boundaries and more accurate lesion information than existing algorithms by utilizing two low-dose CT images. (paper)

  13. Fractional exhaled nitric oxide in diagnosis of bronchial asthma%呼出气一氧化氮检测诊断支气管哮喘

    姚慧娟; 张悦鸣; 李志奎

    2013-01-01

    Objective To assess the accuracy of exhaled nitric oxide for the diagnosis of bronchial asthma (asthma) and to determine the optimal cutoff value.Methods 109 patients received a FeNO test by nitric oxide analyzer (NIOX MINO,Aerocrine AB,Solna,Sweden),referenced the conventional diagnostic methods of asthma.Different FeNO measurements corresponds to different degrees of sensitivity and specificity.The accuracy of FeNO was assessed and the optimal cutoff value of FeNO was determined by the means of the receiver operating characteristic (ROC) curves.Results A total of 109 patients were enrolled,in which 47 cases were diagnosed as asthma.and in which 62 cases were diagnosed as non asthmatics.The asthma group FeNO median (interquartile range) was significantly higher than the non-asthmatic group:70 ppb (87 ppb) vs 16 ppb (21 ppb),P<0.001.The area under the ROC curve was 0.808 (95% CI:0.719 to 0.896,P <0.001).The optimal FeNO cutoff value was 41 ppb with a sensitivity of 68.1%,a specificity of 83.9%,a positive predictive value of 76.2%,a negative predictive value of 77.6% and an accuracy of 77.1%.Conclusions FeNO can be used as an additional diagnostic tool for the screening of patients with a suspected diagnosis of asthma.%目的 评价呼出气一氧化氮(fractional exhaled nitric oxide,FeNO)检测诊断哮喘的准确性及其最佳界值.方法 使用FeNO测试仪(NIOX MINO Aerocrine AB瑞典)对109例疑诊哮喘患者进行FeNO浓度测定,以哮喘的常规诊断方法为参照.不同的FeNO界值对应不同的敏感度和特异度,绘制ROC曲线,评价FeNO诊断哮喘的准确性并得出最佳界值.结果 109例患者中,47例最终被诊断为哮喘,62例非哮喘患者.哮喘组FeNO中位数(四分位数间距)明显高于非哮喘组:70 ppb(87 ppb)比16 ppb(21 ppb),P<0.001.ROC曲线下面积为0.808(95%置信区间:0.719~0.896),FeNO诊断哮喘的最佳界值为41 ppb,以41 ppb为标准诊断哮喘的敏感度为68.1

  14. Adequacy of inhale/exhale breathhold CT based ITV margins and image-guided registration for free-breathing pancreas and liver SBRT

    To evaluate use of breath-hold CTs and implanted fiducials for definition of the internal target volume (ITV) margin for upper abdominal stereotactic body radiation therapy (SBRT). To study the statistics of inter- and intra-fractional motion information. 11 patients treated with SBRT for locally advanced pancreatic cancer (LAPC) or liver cancer were included in the study. Patients underwent fiducial implantation, free-breathing CT and breath-hold CTs at end inhalation/exhalation. All patients were planned and treated with SBRT using volumetric modulated arc therapy (VMAT). Two margin strategies were studied: Strategy I uses PTV = ITV + 3 mm; Strategy II uses PTV = GTV + 1.5 cm. Both CBCT and kV orthogonal images were taken and analyzed for setup before patient treatments. Tumor motion statistics based on skeletal registration and on fiducial registration were analyzed by fitting to Gaussian functions. All 11 patients met SBRT planning dose constraints using strategy I. Average ITV margins for the 11 patients were 2 mm RL, 6 mm AP, and 6 mm SI. Skeletal registration resulted in high probability (RL = 69%, AP = 4.6%, SI = 39%) that part of the tumor will be outside the ITV. With the 3 mm ITV expansion (Strategy 1), the probability reduced to RL 32%, AP 0.3%, SI 20% for skeletal registration; and RL 1.2%, AP 0%, SI 7% for fiducial registration. All 7 pancreatic patients and 2 liver patients failed to meet SBRT dose constraints using strategy II. The liver dose was increased by 36% for the other 2 liver patients that met the SBRT dose constraints with strategy II. Image guidance matching to skeletal anatomy is inadequate for SBRT positioning in the upper abdomen and usage of fiducials is highly recommended. Even with fiducial implantation and definition of an ITV, a minimal 3 mm planning margin around the ITV is needed to accommodate intra-fractional uncertainties

  15. Exhaled volatile organic compounds in patients with non-small cell lung cancer: cross sectional and nested short-term follow-up study

    Acampa Olga

    2005-07-01

    Full Text Available Abstract Background Non-invasive diagnostic strategies aimed at identifying biomarkers of lung cancer are of great interest for early cancer detection. The aim of this study was to set up a new method for identifying and quantifying volatile organic compounds (VOCs in exhaled air of patients with non-small cells lung cancer (NSCLC, by comparing the levels with those obtained from healthy smokers and non-smokers, and patients with chronic obstructive pulmonary disease. The VOC collection and analyses were repeated three weeks after the NSCLC patients underwent lung surgery. Methods The subjects' breath was collected in a Teflon® bulb that traps the last portion of single slow vital capacity. The 13 VOCs selected for this study were concentrated using a solid phase microextraction technique and subsequently analysed by means of gas cromatography/mass spectrometry. Results The levels of the selected VOCs ranged from 10-12 M for styrene to 10-9 M for isoprene. None of VOCs alone discriminated the study groups, and so it was not possible to identify one single chemical compound as a specific lung cancer biomarker. However, multinomial logistic regression analysis showed that VOC profile can correctly classify about 80 % of cases. Only isoprene and decane levels significantly decreased after surgery. Conclusion As the combination of the 13 VOCs allowed the correct classification of the cases into groups, together with conventional diagnostic approaches, VOC analysis could be used as a complementary test for the early diagnosis of lung cancer. Its possible use in the follow-up of operated patients cannot be recommended on the basis of the results of our short-term nested study.

  16. Temperatura do ar exalado, um novo biomarcador no controle da asma: um estudo piloto Exhaled breath temperature, a new biomarker in asthma control: a pilot study

    Raul Emrich Melo

    2010-12-01

    Full Text Available OBJETIVO: Avaliar se a temperatura do ar exalado (TAE, medida por um método não invasivo, é efetiva no monitoramento de pacientes com asma não controlada. MÉTODOS: Estudo piloto com nove pacientes (sete mulheres e dois homens; média de idade: 39 anos com diagnóstico de asma por pelo menos um ano e sem uso de tratamento de manutenção por pelo menos três meses antes do início do estudo. Na primeira visita, os pacientes foram submetidos à espirometria e à medida da TAE. Todos os pacientes foram orientados a iniciar tratamento com budesonida/formoterol (200/6 µg inalatório a cada 12 h por seis semanas. Além disso, os pacientes com asma grave (VEF1 OBJECTIVE: To evaluate whether the exhaled breath temperature (EBT, measured by a noninvasive method, is an effective means of monitoring patients with uncontrolled asthma. METHODS: A pilot study comprising nine patients (seven women and two men; mean age: 39 years diagnosed with asthma at least one year prior to the beginning of the study and not having been under maintenance therapy for the last three months. In the first visit, the patients underwent spirometry and measurement of EBT. The patients were then instructed to use inhaled budesonide/formoterol (200/6 µg every 12 h for six weeks. In addition, the patients with severe asthma (FEV1 < 60% of predicted were instructed to use oral prednisolone (40 mg/day for five days. After six weeks, the patients underwent the same tests. RESULTS: All of the patients reported an improvement in the symptoms of asthma, as confirmed by a statistically significant increase in FEV1 from the first to the second visit (mean, 56.1% vs. 88.7% of predicted; p < 0.05. Five patients used oral prednisolone for the first five days of the treatment period. Six patients used additional doses of inhaled budesonide/formoterol (mean duration, 2.5 weeks. The EBT decreased significantly from the first to the second visit (mean EBT: 35.1ºC vs. 34.1ºC; p < 0

  17. Method for parameter-free determination of Radon exhalation and dimensioning of sealing cover in the remediation of residues of mining sites; Methode zur parameterfreien Bestimmung der Radonexhalation und Dimensionierung von Abdeckschichten bei der Sanierung bergbaulicher Altlasten - Bleispurmethode

    Schulz, H.; Schellenberger, A.; Funke, L.; Rothe, S.

    2000-10-01

    Alternative methods for assessing the protective effect of liners against radon emissions, with the focus on the radon decay product Pb-210. The so-called 'lead track' was used, i.e. the difference of the specific activities of Pb-210 and Ra-226. With a half-life of 22.3 years, Pb-210 is well suited for assessing long-term effects of radon transport by measuring its specific activity in soil samples. Especially measurements of the depth-dependent Pb-210 concentration profiles resp. the lead track in soils and liners provided information on exhalation of radon or radon concentrations in soil air, which reflect the transport patterns over periods of more than 30 years. (orig.) [German] Im Rahmen des Forschungsprojekts wurden Moeglichkeiten einer alternativen Methode zur Beurteilung der Radondaemmwirkung von Abdeckungen untersucht, wobei nicht die Bestimmung der Konzentration von Rn-222, sondern die des Radonfolgeprodukts Pb-210 im Vordergrund stand. Als Untersuchungsgroesse wurde die Differenz der spezifischen Aktivitaet von Pb-210 und Ra-226, die als Bleispur bezeichnet wurde, eingefuehrt. Mit einer Halbwertszeit von 22,3 Jahren ist das Radionuklid Pb-210 praedestiniert, Langzeiteffekte des Radontransports ueber die Messung seiner spezifischen Aktivitaet ih Bodenproben zu extrahieren. Insbesondere die Messung des tiefenabhaengigen Pb-210-Konzentrationsprofils bzw. der Bleispur in Boeden und Abdeckungen liefert Informationen ueber die tatsaechliche Exhalation von Radon bzw. die Radonkonzentration in der Bodenluft, die das Transportverhalten ueber Zeitraeume von mehr als 30 Jahren reflektieren. (orig.)

  18. Rate theory

    This chapter presents the basic principles of cluster dynamics as a particular case of mesoscopic rate theory models developed to investigate fuel behaviour under irradiation such as in UO2. It is shown that as this method simulates the evolution of the concentration of every type of point or aggregated defect in a grain of material. It produces rich information that sheds light on the mechanisms involved in microstructure evolution and gas behaviour that are not accessible through conventional models but yet can provide for improvements in those models. Cluster dynamics parameters are mainly the energetic values governing the basic evolution mechanisms of the material (diffusion, trapping and thermal resolution). In this sense, the model has a general applicability to very different operational situations (irradiation, ion-beam implantation, annealing) provided that they rely on the same basic mechanisms, without requiring additional data fitting, as is required for more empirical conventional models. This technique, when applied to krypton implanted and annealed samples, yields a precise interpretation of the release curves and helps assess migration mechanisms and the krypton diffusion coefficient, for which data is very difficult to obtain due to the low solubility of the gas. (authors)

  19. Fast and highly sensitive fiber-enhanced Raman spectroscopic monitoring of molecular H2 and CH4 for point-of-care diagnosis of malabsorption disorders in exhaled human breath.

    Hanf, Stefan; Bögözi, Timea; Keiner, Robert; Frosch, Torsten; Popp, Jürgen

    2015-01-20

    Breath gas analysis is a novel powerful technique for noninvasive, early-stage diagnosis of metabolic disorders or diseases. Molecular hydrogen and methane are biomarkers for colonic fermentation, because of malabsorption of oligosaccharides (e.g., lactose or fructose) and for small intestinal bacterial overgrowth. Recently, the presence of these gases in exhaled breath was also correlated with obesity. Here, we report on the highly selective and sensitive detection of molecular hydrogen and methane within a complex gas mixture (consisting of H2, CH4, N2, O2, and CO2) by means of fiber-enhanced Raman spectroscopy (FERS). An elaborate FERS setup with a microstructured hollow core photonic crystal fiber (HCPCF) provided a highly improved analytical sensitivity. The simultaneous monitoring of H2 with all other gases was achieved by a combination of rotational (H2) and vibrational (other gases) Raman spectroscopy within the limited spectral transmission range of the HCPCF. The HCPCF was combined with an adjustable image-plane aperture pinhole, in order to separate the H2 rotational Raman bands from the silica background signal and improve the sensitivity down to a limit of detection (LOD) of 4.7 ppm (for only 26 fmol H2). The ability to monitor the levels of H2 and CH4 in a positive hydrogen breath test (HBT) was demonstrated. The FERS sensor possesses a high dynamic range (∼5 orders of magnitude) with a fast response time of few seconds and provides great potential for miniaturization. We foresee that this technique will pave the way for fast, noninvasive, and painless point-of-care diagnosis of metabolic diseases in exhaled human breath. PMID:25545503

  20. Exposure Assessment of Workers Handling Industrial NORM in Japan

    In the study, a dose assessment of workers handling typical industrial NORM was carried out to obtain information for the future regulation system in Japan. The annual effective dose received by workers was estimated using measurements of dose rate and activity concentrations in raw materials, products and aerosols, as well as concentrations of 222Rn and 220Rn decay products in workplaces at plants processing zircon, monazite and titanium ore in Japan. From the results of the dose assessment, a relationship between the concentration of NORM and the average annual dose received by the worker was discussed. (author)

  1. Unconstrained monitoring of long-term heart and breath rates during sleep

    An unconstrained method for the long-term monitoring of heart and breath rates during sleep is proposed. The system includes a sensor unit and a web-based network module. The sensor unit is set beneath a pillow to pick up the pressure variations from the head induced by inhalation/exhalation movements and heart pulsation during sleep. The measured pressure signal was digitized and transferred to a remote database server via the network module. A wavelet-based algorithm was employed to detect the heart and breath rates, as well as body movement, during sleep. The overall system was utilized for a total six-month trial operation delivered to a female subject. The profiles of the heart and breath rates on a beat-by-beat and daily basis were obtained. Movements during sleep were also estimated. The results show that the daily average percentage of undetectable periods (UPs) during 881.6 sleep hours over a 180 day period was 17.2%. A total of 89.2% of sleep hours had a UP of not more than 25%. The profile of the heart rate revealed a periodic property that corresponded to the female monthly menstrual cycle. Our system shows promise as a long-term unconstrained monitor for heart and breath rates, and for other physiological parameters related to the quality of sleep and the regularity of the menstrual cycle. (note)

  2. Exhaled nitric oxide levels in school children of Beijing%北京地区学龄儿童呼出气一氧化氮调查分析

    李硕; 娄小尚; 马煜; 韩胜利; 刘传合; 陈育智

    2010-01-01

    目的 了解北京地区学龄儿童呼出气一氧化氮(eNO)水平.方法 选择北京市11-18岁在校学生,采用过敏件疾病与哮喘的国际间对比研究调查问卷,通过填写问卷及现场体检对儿童进行分组(正常儿童组及曾患不同疾病儿童组),检测eNO水平、峰流速及过敏原.结果 共筛选出正常儿童395名,男177名,女218名.不同性别正常儿童eNO差异无统计学意义(P均>0.05),但与其年龄呈正相关(男性P=0.008,女性P=0.05),在男性与其身高呈正相关(P=0.02).11~14岁、14~18岁正常儿童eNO几何均数(G)分别为11.22、14.13 ppb(ppb=10~9),其95%正常值范围分别为4.17~30.20 ppb、5.50~36.31 ppb.曾患哮喘/喘息(68例)和曾患过敏性鼻炎(96例)儿童eNO几何均数分别是19.05 ppb、14.79 ppb,与正常儿童差异有统计学意义(P分别为0.001、0.008).过敏原皮肤点刺检查阳性与阴性儿童eNO几何均数分别为16.98 ppb、11.75 ppb,两组间差异有统计学意义(P=0.001).结论 北京地区11~18岁正常学龄儿童eNO随年龄波动于10.72~13.80ppb,与年龄、身高呈正相关,与性别无关.喘息性疾病、过敏性鼻炎患儿以及特应性个体eNO水平显著增加.%Objective To learn the normal values of exhaled nitric oxide (eNO) in children. Method School children in Beijing from 11 to 18 years of age were included in the study. All the students were assigned into two groups: normal group and abnormal group (with allergic disease) according to the International Study of Asthma and Allergy in Childhood questionnaires, eNO, peak expiratory flow rate and sensitization were measured. Result Totally 395 students were screened out as normal subject (male: 177, female: 218). The eNO level was not significantly different between genders (P > 0.05 ), but was associated positively with age in both male and female group ( P = 0.008 and P = 0.05 respectively) and associated with height in male students ( P = 0.02 ). The geometric mean

  3. Exhaled breath condensate collection for nitrite dosage: a safe and low cost adaptation Coleta do condensado do ar exalado pulmonar para a dosagem de nitrito: Uma adaptação segura e barata

    Graziela Saraiva Reis

    2010-04-01

    Full Text Available PURPOSE: Standardization of a simple and low cost technique of exhaled breath condensate (EBC collection to measure nitrite. METHODS: Two devices were mounted in polystyrene boxes filled either with crushed ice/salt crystals or dry ice/crushed ice. Blood samples were stored at -70º C for posterior nitrite dosages by chemiluminescence and the Griess reaction. RESULTS: a The use of crushed ice/dry ice or salt revealed sufficient EBC room air collection, but was not efficient for patients under ventilation support; b the method using crushed ice/salt collected greater EBC volumes, but the nitrite concentrations were not proportional to the volume collected; c The EBC nitrite values were higher in the surgical group using both methods; d In the surgical group the nasal clip use diminished the EBC nitrite concentrations in both methods. CONCLUSIONS: The exhaled breath condensate (EBC methodology collection was efficient on room air breathing. Either cooling methods provided successful EBC collections showing that it is possible to diminish costs, and, amongst the two used methods, the one using crushed ice/salt crystals revealed better efficiency compared to the dry ice method.OBJETIVO: Padronizar técnica simples e barata de coleta do condensado do ar exalado pulmonar (CEP para medir nitrito. MÉTODOS: Dois dispositivos foram montados em caixas de isopor e preenchidos com gelo picado/sal grosso ou gelo picado/gelo seco. Amostras de sangue foram armazenadas a -70º C para dosagem de nitrito por quimiluminescência e pela reação de Griess. RESULTADOS: a a utilização de gelo picado/gelo seco ou sal foi eficiente para a coleta em respiração espontânea, mas ineficiente durante ventilação mecânica; b o método gelo picado/sal coletou volumes maiores, sem aumento proporcional do nitrito; c os valores do nitrito foram mais elevados no grupo cirúrgico utilizando os dois métodos; d no grupo cirúrgico com clipe nasal ocorreu diminuição do

  4. Clinical value of fractional exhaled nitric oxide in the diagnosis of bronchial asthma%呼出气一氧化氮诊断支气管哮喘的临床价值

    陈洁; 李秀

    2015-01-01

    Objective To assess the value of fractional exhaled nitric oxide in the diagnosis of bronchial asthma. Methods 87 patients were selected from respiratory department, and their FeNO was strictly detected by nitric oxide analyzer (NIOX MINO). Taking symptoms of asthma and bronchial dilation test as diagnostic gold stand-ard, the accuracy and cutoff value of FeNO was determined by ROC curves. Results 48 cases were finally diag-nosed as asthma, and 39 cases were diagnosed as non-asthma. The level of FeNO was obviously higher in the asthma group than in the non-asthma group (48ppb vs 18ppb, P 18ppb,P <0.05。 ROC 曲线下面积为0.884,最佳临界点为29ppb,以该点作为阈值,诊断哮喘的敏感度为79.1%,特异度为84.6%,阳性预测值为86.4%,阴性预测值为76.7%,准确度为80.5% 。结论 FeNO对支气管哮喘的诊断和鉴别诊断具有可观的敏感性和特异度,可以作为哮喘的辅助诊断工具。

  5. Real Property Tax Rates

    Montgomery County of Maryland — The Levy Year 2012 real property tax rate dataset reflects all the rates per $100 set each year by the County Council. These rates are applied to the assessed value...

  6. Interest Rates as Options.

    Black, Fischer

    1995-01-01

    Since people can hold currency at a zero nominal interest rate, the nominal short rate cannot be negative. The real interest rate can be and has been negative, since low risk real investment opportunities like filling in the Mississippi delta do not guarantee positive returns. The inflation rate can be and has been negative, most recently (in the United States) during the Great Depression. The nominal short rate is the 'shadow real interest rate' (as defined by the investment opportunity set)...

  7. Sovereign credit ratings

    Richard Cantor; Frank Packer

    1995-01-01

    Sovereign ratings are gaining importance as more governments with greater default risk borrow in international bond markets. But while the ratings have proved useful to governments seeking market access, the difficulty of assessing sovereign risk has led to agency disagreements and public controversy over specific rating assignments. Recognizing this difficulty, the financial markets have shown some skepticism toward sovereign ratings when pricing issues.

  8. Interest rate derivatives

    Svenstrup, Mikkel

    This Ph.D. thesis consists of four self-contained essays on valuation of interest rate derivatives. In particular derivatives related to management of interest rate risk care are considered.......This Ph.D. thesis consists of four self-contained essays on valuation of interest rate derivatives. In particular derivatives related to management of interest rate risk care are considered....

  9. Rating mutual funds

    Bechmann, Ken L.; Rangvid, Jesper

    2007-01-01

    We develop a new rating of mutual funds: the atpRating. The atpRating assigns crowns to each individual mutual fund based upon the costs an investor pays when investing in the fund in relation to what it would cost to invest in the fund's peers. Within each investment category, the rating assigns...

  10. Airline Quality Rating 1997

    Bowen, Brent D.; Headley, Dean E.

    1997-01-01

    The Airline Quality Rating (AQR) was developed and first announced in early 1991 as an objective method of comparing airline performance on combined multiple factors important to consumers. Development history and calculation details for the AQR rating system are detailed in The Airline Quality Rating issued in April, 1991, by the National Institute for Aviation Research at Wichita State University. This current report, Airline Quality Rating 1997, contains monthly Airline Quality Rating scor...

  11. Airline Quality Rating 1998

    Bowen, Brent D.; Headley, Dean E.

    1998-01-01

    The Airline Quality Rating (AQR) was developed and first announced in early 1991 as an objective method of comparing airline performance on combined multiple factors important to consumers. Development history and calculation details for the AQR rating system are detailed in The Airline Quality Rating issued in April, 1991, by the National Institute for Aviation Research at Wichita State University. This current report, Airline Quality Rating 1998, contains monthly Airline Quality Rating scor...

  12. Airline Quality Rating 1996

    Bowen, Brent D.; Headley, Dean E.

    1996-01-01

    The Airline Quality Rating (AQR) was developed and first announced in early 1991 as an objective method of comparing airline performance on combined multiple factors important to consumers. Development history and calculation details for the AQR rating system are detailed in The Airline Quality Rating issued in April, 1991, by the National Institute for Aviation Research at Wichita State University. This current report, Airline Quality Rating 1996, contains monthly Airline Quality Rating scor...

  13. Nitrite exhaled breath condensate study in patients undergoing cardiopulmonary bypass cardiac surgery Estudo do nitrito do condensado do exalado pulmonar em pacientes submetidos à cirurgia cardíaca com CEC

    Viviane dos Santos Augusto

    2011-03-01

    Full Text Available BACKGROUND: There is a relative lack of studies on postoperative changes in nitrite (NO2 - concentrations, a marker of injury, following cardiac surgery. In this context, investigations on how exhaled NO concentrations vary in the postoperative period of cardiac surgery will certainly contribute to new clinical findings. OBJECTIVE: The objective of this study was to compare the EBC NO levels in both the pre and postoperative (24 hours periods of cardiac surgery. METHODS: Twenty - eight individuals were divided into three groups: 1 control, 2 coronary artery bypass grafting, and 3 valve surgery. The nitrite (NO2 - levels were measured by chemiluminescence in blood samples and exhaled breath condensate (EBC. Data were analyzed by the Mann - Whitney and Wilcoxon tests. RESULTS: 1 Preoperatively, the EBC NO2 - levels from groups 2 and 3 patients were higher than control individuals; 2 The postoperative (24 hours NO2 - levels in the EBC from group 3 patients were lower compared with preoperative values; 3 The NO2 - levels in the plasma from group 2 patients were lower in the preoperative compared with the postoperative (24h values and; 4 Preoperatively, there was no difference between groups 2 and 3 in terms of plasma NO2 - concentrations. CONCLUSION: These data suggest that NO measurement in EBC is feasible in cardiac surgery patients.INTRODUÇÃO: Estudos mostrando alterações das concentrações de nitrito (NO2 - exalado, com biomarcador de lesão, são raros em pacientes submetidos à cirurgia cardíaca. Nesse contexto, o seu estudo no pré e pós - operatório de cirurgias cardíacas poderá contribuir para novos dados clínicos. OBJETIVO: O objetivo foi comparar os níveis de nitrito (NO2 - do condensado do exalado pulmonar (CEP no pré e pós - operatório de cirurgia cardíaca com circulação extracorpórea. MÉTODOS: Vinte e oito indivíduos foram alocados em três grupos: 1 controle, 2 revascularização do miocárdio e 3 corre

  14. An Evaluation of Thermal Imaging Based Respiration Rate Monitoring in Children

    Farah AL-Khalidi

    2011-01-01

    Full Text Available Problem statement: An important indicator of an individual’s health is respiration rate. It is the average number of times air is inhaled and exhaled per minute. Existing respiration monitoring methods require an instrument to be attached to the patient’s body during the recording. This is a discomfort to the patient and the instrument can be dislodged from its position. Approach: In this study a novel noncontact, thermal imaging based respiration rate measurement method is developed and evaluated. Facial thermal videos of 16 children (age: Median = 6.5 years, minimum = 6 months, maximum = 17 years were processed in the study. The recordings were carried out while the children rested comfortably on a bed. The children’s respiration rates were also simultaneously measured using a number of conventional contact based methods. Results: This allowed comparisons with the thermal imaging method to be carried out. The image capture rate was 50 frames per second and the duration of a thermal video recording was 2 min per child. The thermal images were filtered and segmented to identify the nasal region. An algorithm was developed to automatically track the identified nasal area. This region was partitioned into eight equal concentric segments. The pixel values within each segment were averaged to produce a single thermal feature for that segment of the image. A respiration signal was obtained by plotting each segment��€™s feature against time. Conclusion: Respiration rate values were automatically calculated by determining the number of oscillations in the respiration signals per minute. A close correlation (coefficient = 0.994 was observed between the respiration rates measured using the thermal imaging method and those obtained using the most effective conventional contact based respiration method.

  15. How long may a breath sample be stored for at  -80 °C? A study of the stability of volatile organic compounds trapped onto a mixed Tenax:Carbograph trap adsorbent bed from exhaled breath.

    Kang, S; Paul Thomas, C L

    2016-01-01

    Thermal desorption is used extensively in exhaled breath volatile organic compound (VOC) analysis, and it is often necessary to store the adsorbent tube samples before analysis. The possible introduction of storage artefacts is an important potential confounding factor in the development of standard methodologies for breath sampling and analysis. The stability of VOCs trapped from breath samples onto a dual bed Tenax(®) TA:Carbograph adsorbent tube and stored  -80°C was studied over 12.5 month. 25 samples were collected from a single male participant over 3 h and then stored at  -80 °C. Randomly selected adsorbent tubes were subsequent analysed by thermal desorption-gas chromatography-mass spectrometry at 5 times points throughout the 12.5 month of the study. Toluene-d8, decane-d22 and hexadecane-d34 internal standards were used to manage the instrument variability throughout the duration of the study. A breath-matrix consisting of 161 endogenous and 423 exogenous VOC was created. Iterative orthogonal partial least squared discriminant analysis (OPLS-DA) and principal components analysis (PCA) indicated that it was not possible to detect storage artefacts at 1.5 month storage. By 6 month storage artefacts were discernible with significant changes observed for 27% of the recovered VOC. Endogenous VOC were observed to be more susceptible to storage. A paired two-tailed t-test on the endogenous compounds indicated that the maximum storage duration under these conditions was 1.5 month with 94% of the VOCs stable. This study indicates that a prudent approach is best adopted for the storage of adsorbent samples; storage times should be minimised, and storage time examined as a possible discriminatory factor in multivariate analysis. PMID:27272219

  16. Argonne-Utah studies of 224Ra endosteal surface dosimetry

    The activities of 212Pb relative to 224Ra and of 222Rn relative to 226Ra were measured in bone surface deposits 24 h after injection of radium into beagles. The fractional retention of 220Rn atoms was measured in vitro with hydrated and dehydrated bone samples to determine the effect of water content on the escape of radon from bone surfaces. The experimental data suggest that substantial 224Ra daughter-product disequilibrium exists in bone surface deposits. Estimates for the lower and upper limits on the fractional retention of 220Rn in vivo are 0.05 and 0.25, respectively. The average bone surface activity of 212Pb relative to 224Ra ranged from 0.34 to 0.71 for four dogs, with the majority of the values toward the lower end of the range. Only a small portion of the deposited 212Pb came from lead in the injection solution despite near equilibrium between 224Ra and its daughters at the time of injection. The retention data indicate that the endosteal tissue dose rate in the dogs at one day was actually one-third to about one-half that which would be calculated assuming equilibrium of 224Ra daughter products in bone surface deposits. 11 references, 2 figures, 7 tables

  17. Equilibration correction of temporal measurements for sudden 222Rn concentration changes

    Tan, Y.; Tokonami, S.; Liu, H.; Kearfott, K. J.

    2016-02-01

    222Rn and 220Rn can be used as tracers of groundwater or submarine springs, and 222Rn in water also could indicate indoor radon problems in some regions. The half-life of 222Rn is long enough that its concentration may remain significant during transit over relatively long distances, while that of 220Rn is not. Prior research revealed that it took about 15 min for the radon to achieve gas equilibrium at a water flow rate of 17.5 L min-1, which is approximately equivalent to the time required for the 222Rn-218Po pair to approach radioactive equilibrium and is limiting in terms of measurements of sudden radon concentration change. In this work, an algorithm is applied to improve the continuous tracing of radon concentrations in the field environment. Results of a laboratory experiment analyzed applying the analysis method illustrated its ability to allow immediate identification of sharp concentration increases. In this paper we find that a precipitous drop in radon concentrations lead to improper corrected values as the result of measurement uncertainties prior to the drop, and a method using zero instead negative values for reducing the uncertainties under such condition also is proposed.

  18. Increased indoor Rn levels due to actinide containing mineral collections displayed in living areas

    Collection of crystals ranging from quartz to U or Th containing minerals is a widespread spare time activity in Switzerland. Radon emanation from stones displayed in showcases in the living area may contribute considerably to elevated Rn levels in the indoor air. Time-averaged Rn gas measurements in 35 homes of subscribers to a journal for mineral collectors showed an unexpected statistically significant increase of 98 Bq m-3 in the Rn level of the room containing the collections compared to the levels measured in a control room on the same floor. Using ICRP Publication 50 conversion factors for indoor exposure to Rn decay products, the additional effective dose equivalent contracted was estimated to amount to an average of 2.7 mSv y-1. Although the 220Rn emanation rate, as measured in the display cases, was considerable in several cases, the dose from 220Rn decay products in the living area remained always a small fraction of the Rn dose. Remedial actions for crystal collections containing considerable amounts of U- or Th-based minerals are suggested

  19. Equilibration correction of temporal measurements for sudden 222Rn concentration changes

    222Rn and 220Rn can be used as tracers of groundwater or submarine springs, and 222Rn in water also could indicate indoor radon problems in some regions. The half-life of 222Rn is long enough that its concentration may remain significant during transit over relatively long distances, while that of 220Rn is not. Prior research revealed that it took about 15 min for the radon to achieve gas equilibrium at a water flow rate of 17.5 L min−1, which is approximately equivalent to the time required for the 222Rn-218Po pair to approach radioactive equilibrium and is limiting in terms of measurements of sudden radon concentration change. In this work, an algorithm is applied to improve the continuous tracing of radon concentrations in the field environment. Results of a laboratory experiment analyzed applying the analysis method illustrated its ability to allow immediate identification of sharp concentration increases. In this paper we find that a precipitous drop in radon concentrations lead to improper corrected values as the result of measurement uncertainties prior to the drop, and a method using zero instead negative values for reducing the uncertainties under such condition also is proposed

  20. The rating reliability calculator

    Solomon David J

    2004-04-01

    Full Text Available Abstract Background Rating scales form an important means of gathering evaluation data. Since important decisions are often based on these evaluations, determining the reliability of rating data can be critical. Most commonly used methods of estimating reliability require a complete set of ratings i.e. every subject being rated must be rated by each judge. Over fifty years ago Ebel described an algorithm for estimating the reliability of ratings based on incomplete data. While his article has been widely cited over the years, software based on the algorithm is not readily available. This paper describes an easy-to-use Web-based utility for estimating the reliability of ratings based on incomplete data using Ebel's algorithm. Methods The program is available public use on our server and the source code is freely available under GNU General Public License. The utility is written in PHP, a common open source imbedded scripting language. The rating data can be entered in a convenient format on the user's personal computer that the program will upload to the server for calculating the reliability and other statistics describing the ratings. Results When the program is run it displays the reliability, number of subject rated, harmonic mean number of judges rating each subject, the mean and standard deviation of the averaged ratings per subject. The program also displays the mean, standard deviation and number of ratings for each subject rated. Additionally the program will estimate the reliability of an average of a number of ratings for each subject via the Spearman-Brown prophecy formula. Conclusion This simple web-based program provides a convenient means of estimating the reliability of rating data without the need to conduct special studies in order to provide complete rating data. I would welcome other researchers revising and enhancing the program.