record 401 of 474 author(s): arnold, d (arnold, d.)

Record 401 of 474

Author(s): Arnold, D (Arnold, D.); Vargas, A (Vargas, A.); Vermeulen, AT (Vermeulen, A. T.); Verheggen, B (Verheggen, B.); Seibert, P (Seibert, P.)

Title: Analysis of radon origin by backward atmospheric transport modelling

Source: ATMOSPHERIC ENVIRONMENT, 44 (4): 494-502 FEB 2010

Abstract: This work shows how ambient radon concentrations measured at Cabauw station in central Netherlands are influenced by transport from different regions under typical transport conditions occurring during April and November, 2007 by means of atmospheric Lagrangian particle dispersion modelling in a receptor-oriented approach. Four specific regions have been isolated to assess their contribution to the modelled radon ambient concentrations at Cabauw, and two different radon flux assumptions.. Westerly flows coming from the ocean are poor in radon and do not increase radon air concentrations unless there is some fetch over the British Isles. Continental transport, mainly from eastern and southern Europe, significantly increases radon background concentrations, reaching increments of 3 Bq m(-3). A constant 0.66 atoms cm(-2) s(-1) radon flux over land and zero over water bodies is a good approximation for the source term in order to study regional contributions and modulation of the radon background. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1352-2310

DOI: 10.1016/j.atmosenv.2009.11.003

Record 402 of 474

Author(s): Kadi, MW (Kadi, Mohammad W.)

Title: Rn-222 in Some Underground Water-Samples and Examination of Correlation to U-238 Concentration

Source: ASIAN JOURNAL OF CHEMISTRY, 22 (1): 148-152 JAN 2010

Abstract: The concentration of U-238 and Rn-222 has been assessed in underground water samples collected from the Makkah Al-Mukarramah area west of Saudi Arabia. Observed radon activities lie in the range 0.6-3.9 Bq/L. This range is within the natural limits of concentration of radon. Radon concentrations observed in this study are compared to those observed in a study of radon concentrations in the central region of Saudi Arabia. In the experimental setup, CR-39 detectors are exposed to radon emanating from water samples for 30d. Uranium concentrations lie within the range 1.02-31.97 mu g/L. No direct correlation is found between concentrations of the two isotopes; however radon content in water is much higher than that of uranium.

ISSN: 0970-7077

Record 403 of 474

Author(s): Xu, BC (Xu, Bo-chao); Burnett, WC (Burnett, W. C.); Lane-Smith, D (Lane-Smith, Derek); Yu, ZG (Yu, Zhi-gang)

Title: A simple laboratory-based radon calibration system

Source: JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY, 283 (2): 457-463 FEB 2010

Abstract: Measurements of Rn-222 ("radon") in the environment are important in the geosciences and radiation-protection fields. We demonstrate here a simple laboratory-based calibration system to evaluate the efficiency of radon detectors with a reproducibility of about +/- 2%. The system uses a closed-loop air circulation design with Ra-226 adsorbed onto MnO2-impregnated fiber as a radon source. Two RAD7 radon detectors (Durridge Co., Inc.) that were precisely calibrated at Durridge's in-house calibration facility are used as secondary standards. By parallel analysis of the radon-enriched air within the closed loop, the test RAD7s are assigned a calibration coefficient to be applied to future measurements. We also performed a side-by-side intercomparison with two RAD7s in a high-radon natural environmental setting (limestone cave in Florida) that produced comparable results.

ISSN: 0236-5731

DOI: 10.1007/s10967-009-0427-6

Record 404 of 474

Author(s): Kamenik, J (Kamenik, J.); Holgye, Z (Hoelgye, Z.)

Title: Contamination problems from glass beaker inner surface in low level Po-210 analysis


Abstract: It was found that heating of diluted nitric or hydrochloric acids in many years stored glass beakers can result in mBq quantities of Po-210 leached from beaker walls to the solution. In the case of freshly bought beakers acid leaching of Po-210 was not observed. We suppose that acid leachable Po-210 in old beakers is mainly due to implantation of radon progenies (from air) into superficial layers of glass beaker walls.

ISSN: 0236-5731

DOI: 10.1007/s10967-009-0355-5

Record 405 of 474

Author(s): Darko, EO (Darko, E. O.); Adukpo, OK (Adukpo, O. K.); Fletcher, JJ (Fletcher, J. J.); Awudu, AR (Awudu, A. R.); Otoo, F (Otoo, F.)

Title: Preliminary studies on Rn-222 concentration in ground water from selected areas of the Accra metropolis in Ghana


Abstract: Preliminary studies on groundwater samples from selected wells in three communities in the Greater Accra region of Ghana have been carried out to determine the concentration of Rn-222. The studies were carried out in the dry season when the weather conditions were fairly stable and the communities depend mostly on groundwater sources for domestic use during this period. Measurements were carried out using gamma spectrometry. The average activity concentration obtained was 8.1 Bq/L with an average annual effective dose of 59.2 mu Sv. The result is within the range published by other countries and the recommended limit for radon in drinking water set by the World Health Organization.

ISSN: 0236-5731

DOI: 10.1007/s10967-009-0378-y

Record 406 of 474

Author(s): Burnett, WC (Burnett, William C.); Peterson, RN (Peterson, Richard N.); Santos, IR (Santos, Isaac R.); Hicks, RW (Hicks, Richard W.)

Title: Use of automated radon measurements for rapid assessment of groundwater flow into Florida streams

Source: JOURNAL OF HYDROLOGY, 380 (3-4): 298-304 JAN 30 2010

Abstract: Naturally occurring Rn-222 (radon; t(1/2) = 3.8 days) is a good natural tracer of groundwater discharge because it is conservative and typically 2-3 orders of magnitude higher in groundwater than surface waters. In addition, new technology has allowed rapid and inexpensive field measurements of radon-in-water. Results from the C-25 Canal, a man-made canal in east-central Florida thought to be dominated by groundwater inflows, display how one can quickly assess a water body for locations of groundwater inputs. Although only the eastern portion of the canal was surveyed, use of a few assumptions together with some continuous radon measurements allowed reasonable estimates of the groundwater inflows to be made. Groundwater discharge estimates of 327,000 m(3)/day and 331,000 m(3)/day were measured for two stations based on determining the groundwater fraction of the total stream flow. This fraction in each case was calculated by correcting radon concentrations for decay over transit times determined from concentration differences between the apparent focal point of groundwater discharge (with a concentration of 520 +/- 80 dpm/L) estimated to be similar to 17.7 km upstream from the downstream sample locations. During the same period, an average flow of 312,000 +/- 70.000 m(3)/day was determined from time-series measurements of radon at a fixed downstream location. Coincident current meter readings and a measured cross-section area allowed an independent assessment of the total stream discharge of 336,000 m(3)/day. The radon-derived estimates thus indicate that >90% of the total flow is groundwater derived, consistent with the known characteristics of this waterway. (C) 2009 Elsevier B.V. All rights reserved.

ISSN: 0022-1694

DOI: 10.1016/j.jhydrol.2009.11.005

Record 407 of 474

Author(s): Werzi, R (Werzi, R.)

Title: Modeling the Pb-212 activity concentration in the lower atmosphere

Source: JOURNAL OF ENVIRONMENTAL RADIOACTIVITY, 101 (2): 89-94 FEB 2010

Abstract: A worldwide radionuclide network of 80 stations, part of the International Monitoring System, is being setup to monitor compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT). The radioactivity sampled at these stations is primarily Rn-220 progenies affecting the detection capability. A model linking the Rn-220 emanation with the sampled Pb-212 activity was developed and is presented here. The model and the performed measurements show that the variation of the sampled Pb-212 activity can be fully explained by the variation of the local Rn-220 activity concentration. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 0265-931X

DOI: 10.1016/j.jenvrad.2009.08.014

Record 408 of 474

Author(s): Abe, T (Abe, Takuya); Kosako, T (Kosako, Toshiso); Komura, K (Komura, Kazuhisa)

Title: Relationship between variations of Be-7, Pb-210 and Pb-212 concentrations and sub-regional atmospheric transport: Simultaneous observation at distant locations


Abstract: In order to investigate the applicability of Pb-212 as a tracer for atmospheric transportin the sub-regional scale (few hundred kilometers in horizontal direction and up to similar to 1 km by height), we measured the air concentrations of the short-lived radionuclide Pb-212 along with the long-lived Be-7 and Pb-212 near the ground surface. For this purpose, simultaneous observations were continued for several days at three locations: a reference point representative for standard land surface atmosphere conditions, a second location at an altitude 650 m near the reference point, and on a solitary island similar to 180 km from the reference point. Measurements of radioactivity in aerosol particle samples collected at intervals of 2-3 h with a high-volume air sampler were performed by extremely low background gamma-ray spectrometry with the use of Ge detectors located at the Ogoya Underground Laboratory. Concentration of Be-7 or Pb-212 and their variation patterns was found to be similar among the three points during the whole observation period except for moment of the passage of a cold front. The results indicate that distributions of concentrations of the long-lived nuclides were uniform in this range. On the other hand, concentration levels and the variation patterns of the short-lived Pb-212 differed greatly from one location to another, reflecting differences in geographical location and altitude of the observation points. Additionally, there were certain indications that observed concentration of Pb-212 contained two components: an autogenous component from sources nearby and a heterogenous one from fat-away sources carried by atmospheric horizontal transport. Results of this study provide experimental proof that Pb-212 can be used as a tracer of sub-regional atmospheric transport. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 0265-931X

DOI: 10.1016/j.jenvrad.2009.09.004

Record 409 of 474

Author(s): Anjos, RM (Anjos, R. M.); Umisedo, N (Umisedo, N.); da Silva, AAR (da Silva, A. A. R.); Estellita, L (Estellita, L.); Rizzotto, M (Rizzotto, M.); Yoshimura, EM (Yoshimura, E. M.); Velasco, H (Velasco, H.); Santos, AMA (Santos, A. M. A.)

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


Abstract: Radon and gamma radiation level measurements were carried out inside the La Carolina mine, one of the oldest gold mining camps of southern South America, which is open for touristic visits nowadays. CR-39 track-etch detectors and thermoluminescent dosimeters of natural CaF2 and LiF TLD-100 were exposed at 14 points along the mine tunnels in order to estimate the mean Rn-222 concentration and the ambient dose equivalent during the summer season (November 2008 to February 2009). The values for the Rn-222 concentration at each monitoring site ranged from 1.8 +/- 0.1 kBq m(-3) to 6.0 +/- 0.5 kBq m(-3), with a mean value of 4.8 kBq m(-3), indicating that these measurements exceed in about three times the upper action level recommended by ICRP for workplaces. The correlations between radon and gamma radiation levels inside the mine were also investigated. Effective doses due to Rn-222 and gamma rays inside the mine were determined, resulting in negligible values to tourists. Considering the effective dose to the mine tourist guides, values exceeding 20 mSv of internal contribution to the effective doses can be reached, depending on the number of working hours inside the mine. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 0265-931X

DOI: 10.1016/j.jenvrad.2009.09.010

Record 410 of 474

Author(s): Lewis, RK (Lewis, Robert K.); Harley, NH (Harley, Naomi H.)

Title: EMPLOYEE EXPOSURE TO Rn-222 AND Rn-220 IN THREE FISH CULTURE STATIONS IN PENNSYLVANIA

Source: HEALTH PHYSICS, 98 (3): 466-470 MAR 2010

Abstract: Employee exposures to Rn-222 and Rn-220 were measured in three Commonwealth fish hatcheries using specially designed personal dosimeters to determine whether remediation might be necessary. Employees utilizing the hatch house would wear the dosimeter and keep track of their time in the hatch house. Area detectors were also deployed full time in each hatch house. Exposure measurements were compared to U.S. Nuclear Regulatory Commission, U.S. Environmental Protection Agency, and Occupational Safety and Health Administration exposure limits. All measured employee exposures to Rn-222 and Rn-220 were very low and well below currently established regulatory limits. However, hatch house radon concentrations are significantly elevated above the U.S. Environmental Protection Agency residential guideline of 148 Bq m(-3). Health Phys. 98(3):466-470; 2010

ISSN: 0017-9078

DOI: 10.1097/HP.0b013e3181bc8492

Record 412 of 474

Author(s): Arazi, L (Arazi, L.); Cooks, T (Cooks, T.); Schmidt, M (Schmidt, M.); Keisari, Y (Keisari, Y.); Kelson, I (Kelson, I.)

Title: The treatment of solid tumors by alpha emitters released from Ra-224-loaded sources-internal dosimetry analysis

Source: PHYSICS IN MEDICINE AND BIOLOGY, 55 (4): 1203-1218 FEB 21 2010

Abstract: Diffusing alpha-emitters radiation therapy (DART) is a proposed new form of brachytherapy, allowing the treatment of solid tumors by alpha particles. DART utilizes implantable sources carrying small activities of radium-224, which continually release into the tumor radon-220, polonium-216 and lead-212 atoms, while radium-224 itself remains fixed to the source. The released atoms disperse inside the tumor by diffusive and convective processes, creating, through their alpha emissions, a high-dose region measuring several mm in diameter about each source. The efficacy of DART has been demonstrated in preclinical studies on mice-borne squamous cell carcinoma and lung tumors and the method is now being developed toward clinical trials. This work studies DART safety with respect to the dose delivered to distant organs as a result of lead-212 leakage from the tumor through the blood, relying on a biokinetic calculation coupled to internal dose assessments. It is found that the dose-limiting organs are the kidneys and red bone marrow. Assuming a typical source spacing of similar to 5 mm and a typical radium-224 activity density of 0.4-0.8 MBq g(-1) of tumor tissue, it is predicted that tumors weighing up to several hundred grams may be treated without reaching the tolerance dose in any organ.

ISSN: 0031-9155

DOI: 10.1088/0031-9155/55/4/020

Record 415 of 474

Author(s): Hassan, NM (Hassan, Nabil M.); Ishikawa, T (Ishikawa, Tetsuo); Hosoda, M (Hosoda, Masahiro); Sorimachi, A (Sorimachi, Atsuyuki); Tokonami, S (Tokonami, Shinji); Fukushi, M (Fukushi, Masahiro); Sahoo, SK (Sahoo, Sarata K.)

Title: Assessment of the natural radioactivity using two techniques for the measurement of radionuclide concentration in building materials used in Japan

Source: JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY, 283 (1): 15-21 JAN 2010

Abstract: The specific activities of U-238, Th-232, and K-40 in selected building materials used in Japan were measured using a high-purity germanium detector. The uranium and thorium concentrations were determined from same samples using inductively coupled plasma mass spectrometry. There was a good agreement between the measurement of uranium and thorium with both methods (R-2 = 0.94, and 0.97,

respectively). Based on the specific activities, we have estimated some hazard indexes such as radium equivalent activities (Ra-eq), external hazard index (H-ex), internal hazard index (H-in), annual gonadal equivalent dose (AGED), internal alpha dose, mass exhalation rate and emanation coefficient of radon.

ISSN: 0236-5731

DOI: 10.1007/s10967-009-0050-6

Record 416 of 474

Author(s): Smetanova, I (Smetanova, Iveta); Holy, K (Holy, Karol); Mullerova, M (Mullerova, Monika); Polaskova, A (Polaskova, Anna)

Title: The effect of meteorological parameters on radon concentration in borehole air and water

Source: JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY, 283 (1): 101-109 JAN 2010

Abstract: Seasonal and short term variations of Rn-222 activity concentration in borehole air and water of the borehole drilled in cracked quartzite were studied and possible response on meteorological parameters was examined. Seasonal change of radon concentration in borehole air due to atmospheric temperature was confirmed. Short term variation of radon concentration in borehole air coincided with the atmospheric pressure changes. The strong impact of rainfall on radon concentration values was observed both in air and water environments. The decrease of radon content in borehole air and water followed radioactive decay law exclusively in spring and summer month. Contrary to borehole water, rainfall increased radon concentration in borehole air during spring and summer months only. In this paper the results from two and half years of investigation are presented.

ISSN: 0236-5731

DOI: 10.1007/s10967-009-0128-1

Record 417 of 474

Author(s): Baykara, O (Baykara, Oktay); Dogru, M (Dogru, Mahmut)

Title: Assessment of natural radioactivity and heavy metals in water and soil around seismically active area

Source: JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY, 283 (3): 547-553 MAR 2010

Abstract: The natural radioactivity concentration and some heavy metals in various water and soil samples collected from seismically active area have been determined. Gross-alpha and beta concentrations of different 33 water samples and some heavy metal (Fe, Pb, Cu, K, Mn, Cr and Zn) concentration in 72 soil samples collected from two major fault systems (North and East Anatolian Active Fault Systems) in Turkey have been studied. This survey regarding gross-alpha and beta radioactivity and some heavy metals concentrations was carried out by means of Krieger method using a gross-alpha and beta-counting system and atomic absorption spectrometry (AAS), respectively. Also, gross annual effective dose from the average gross-alpha activity in waters were calculated.

ISSN: 0236-5731

DOI: 10.1007/s10967-009-0387-x

Record 418 of 474

Author(s): Mitev, K (Mitev, K.); Madzhunkov, Y (Madzhunkov, Y.); Gerganov, G (Gerganov, G.); Dimitrova, I (Dimitrova, I.); Georgiev, S (Georgiev, S.); Pressyanov, D (Pressyanov, D.)

Title: Automatic Counting of Electrochemically Etched Tracks in Compact Discs. Application to Retrospective Measurements of Rn-222

Source: IEEE TRANSACTIONS ON NUCLEAR SCIENCE, 57 (1): 300-308 Part 2 FEB 2010

Abstract: This work describes an algorithm for automatic counting of alpha tracks in scanned images of electrochemically etched CDs and DVDs. It is demonstrated that the algorithm copes with the specific problems encountered in retrospective Rn-222 measurements with CDs and DVDs; it reliably separates overlapping tracks and ignores artifacts in the image. The algorithm is validated by comparison to manual counting and a very good correlation is found. The measurement range of Rn-222 concentrations in dwellings and soil gas is estimated. It is shown that the wide span of track densities that can be covered by the algorithm combined with the specific advantages of the compact disc method can provide reliable measurements in the whole range of Rn-222 concentrations of practical interest. For retrospective measurements of Rn-222 in dwellings the estimated range is from 10 Bq/m(3) to 100 kBq/m(3) for five years exposure time. For Rn-222 in soil gas the estimated range is from 1 kBq/m(3) to 10 MBq/m(3) for

ten days exposure time.

ISSN: 0018-9499

DOI: 10.1109/TNS.2009.2036436

Record 419 of 474

Author(s): Schmidt, A (Schmidt, A.); Gibson, JJ (Gibson, J. J.); Santos, IR (Santos, I. R.); Schubert, M (Schubert, M.); Tattrie, K (Tattrie, K.); Weiss, H (Weiss, H.)

Title: The contribution of groundwater discharge to the overall water budget of two typical Boreal lakes in Alberta/Canada estimated from a radon mass balance

Source: HYDROLOGY AND EARTH SYSTEM SCIENCES, 14 (1): 79-89 2010

Abstract: Radon-222, a naturally-occurring radioisotope with a half-life of 3.8 days, was used to estimate groundwater discharge to small lakes in wetland-dominated basins in the vicinity of Fort McMurray, Canada. This region is under significant water development pressure including both oil sands mining and in situ extraction. Field investigations were carried out in March and July 2008 to measure radon-222 distributions in the water column of two lakes as a tracer of groundwater discharge. Radon concentrations in these lakes ranged from 0.5 to 72 Bq/m(3), while radon concentrations in groundwaters ranged between 2000 and 8000 Bq/m(3). A radon mass balance, used in comparison with stable isotope mass balance, suggested that the two lakes under investigation had quite different proportions of annual groundwater inflow (from 0.5% to about 14% of the total annual water inflow). Lower discharge rates were attributed to a larger drainage area/lake area ratio which promotes greater surface connectivity. Interannual variability in groundwater proportions is expected despite an implied seasonal constancy in groundwater discharge rates. Our results demonstrate that a combination of stable isotope and radon mass balance approaches provides information on flowpath partitioning that is useful for evaluating surface-groundwater connectivity and acid sensitivity of individual water bodies of interest in the Alberta Oil Sands Region.

ISSN: 1027-5606

Record 420 of 474

Author(s): Ershaidat, NM (Ershaidat, N. M.); Abu-Jaber, NS (Abu-Jaber, N. S.); Al-Bataina, BA (Al-Bataina, B. A.); Shobaki, JM (Shobaki, J. M.); Jaradat, AS (Jaradat, A. S.)

Title: Relationship between the effective diffusion coefficient of soil radon and groundwater recharge in semi-arid areas

Source: ENVIRONMENTAL EARTH SCIENCES, 59 (2): 261-268 NOV 2009

Abstract: Herein, the relationship between soil radon behavior and groundwater recharge in the town of Hosha, a semi-arid area of Jordan is explored. The annual rainfall average in this area is between 60-100 mm year(-1). Soil radon concentration levels, using CR-39 detectors, have been measured at several depths. Nine sampling sites on a hill slope, in the summer and winter 2006 were chosen. Other soil parameters such as moisture, soil type and porosity were also measured. Correlation between the latter and the calculated effective diffusion coefficients, based on a linear approximation, was done in order to explore water movement. A weak correlation between the soil radon concentration and water recharge in this particular semi-arid area is observed. The results show that water recharge takes place vertically, i.e., water moves downward and in one of the nine sampling sites this movement seems to be more rapid compared to the other sites.

ISSN: 1866-6280

DOI: 10.1007/s12665-009-0023-7

Record 421 of 474

Author(s): Chen, J (Chen, Jing)

Title: A preliminary design of a radon potential map for Canada: a multi-tier approach

Source: ENVIRONMENTAL EARTH SCIENCES, 59 (4): 775-782 DEC 2009

Abstract: Canada is a vast country with most of the population living on a small portion of the land. However, for a national radon potential map, it is mandatory to cover the entire country including sparsely populated areas. Because of these characteristics, the radon map development for Canada is challenging. After briefly reviewing of radon map development in the world, this study considers a multi-tier approach to best use available however limited resources and to generate a national radon map in a timely fashion. In summary, radon potential maps for highly populated areas should be determined by

direct indoor radon measurements where enough indoor radon data are available. In areas where indoor radon measurements are limited or not yet available, the radon potential maps could be developed from various data sources with a multi-factor scoring system including geological information on soil permeability, soil gas radon concentration and ground uranium concentration. In sparsely populated areas, radon potential maps can only be generated with geological predictive tools, especially in those areas where no houses have yet been built. Because indoor radon measurement data and geological information relevant to radon are very limited in Canada, a multi-step strategy is also worth considering in addition to the multi-tier approach.

ISSN: 1866-6280

DOI: 10.1007/s12665-009-0073-x

Record 422 of 474

Author(s): Kowalczk, AJ (Kowalczk, Andrew J.); Froelich, PN (Froelich, Philip N.)

Title: Cave air ventilation and CO2 outgassing by radon-222 modeling: How fast do caves breathe?

Source: EARTH AND PLANETARY SCIENCE LETTERS, 289 (1-2): 209-219 JAN 15 2010

Abstract: In general, the rate and timing of calcite precipitation is in part affected by variations in cave air CO2 concentrations. Knowledge of cave ventilation processes is required to quantify the effect variations in CO2 concentrations have on speleothem deposition rates and thus paleoclimate records. In this study we use radon-222 (Rn-222) as a proxy of ventilation to estimate CO2 outgassing from the cave to the atmosphere, which can be used to infer relative speleothem deposition rates. Hollow Ridge Cave, a wild cave preserve in Marianna, Florida, is instrumented inside and out with multiple micro-meteorological sensor stations that record continuous physical and air chemistry time-series data. Our time series datasets indicate diurnal and seasonal variations in cave air Rn-222 and CO2 concentrations, punctuated by events that provide clues to ventilation and drip water degassing mechanisms. Average cave air Rn-222 and CO2 concentrations vary seasonally between winter (Rn-222 = 50 dpm L-1, where 1 dpm L-1 = 60 Bq m(-3); CO2 = 360 ppmv) and summer (Rn-222 = 1400 dpm L-1; CO2 = 3900 ppmv). Large amplitude diurnal variations are observed during late summer and autumn (Rn-222 = 6 to 581 dpm L-1; CO2 = 360 to 2500 ppmv). We employ a simple first-order Rn-222 mass balance model to estimate cave air exchange rates with the outside atmosphere. Ventilation occurs via density driven flow and by winds across the entrances which create a 'venturi' effect. The most rapid ventilation occurs 25 m inside the cave near the entrance: 45 h(-1) (1.33 min turnover time). Farther inside (175 m) exchange is slower and maximum ventilation rates are 3 h(-1) (22 min turnover time). We estimate net CO2 flux from the epikarst to the cave atmosphere using a CO2 mass balance model tuned with the Rn-222 model. Net CO2 flux from the epikarst is highest in summer (72 mmol m(-2) day(-1)) and lowest in late autumn and winter (12 mmol m(-2) day(-1)). Modeled ventilation and net CO2 fluxes are used to estimate net CO2 outgassing from the cave to the atmosphere. Average net CO2 outgassing is positive (net loss from the cave) and is highest in late summer and early autumn (about 4 mol h(-1)) and lowest in winter (about 0.5 mol h(-1)). Modeling of ventilation, net CO2 flux from the epikarst, and CO2 outgassing to the atmosphere from cave monitoring time-series can help better constrain paleoclimatic interpretations of speleothem geochemical records. (C) 2009 Elsevier B.V. All rights reserved.

ISSN: 0012-821X

DOI: 10.1016/j.epsl.2009.11.010

Record 423 of 474

Author(s): Jolly, D (Jolly, D.); Meyer, J (Meyer, J.)

Title: A brief review of radiation hormesis

Source: AUSTRALASIAN PHYSICAL & ENGINEERING SCIENCES IN MEDICINE, 32 (4): 180-187 DEC 2009

Abstract: This paper reviews physical, experimental and epidemiological evidence for and against radiation hormesis and discusses implications with regards to radiation protection. The scientific community is still divided on the premise of radiation hormesis, with new literature published on a regular basis. The International Commission on Radiological Protection (ICRP) recommends the use of the Linear No Threshold (LNT) model, for planning radiation protection. This model states that the probability of induced cancer and hereditary effects increases with dose in a linear fashion. As a consequence, all radiation exposures must be justified and have a sufficient protection standard in place so that exposures are kept below certain dose limitations. The LNT model has sufficient evidence at high doses but has been extrapolated in a linear fashion to low dose regions with much less scientific evidence. Much

experimentation has suggested discrepancies of this extrapolation at low doses. The hypothesis of radiation hormesis suggests low dose radiation is beneficial to the irradiated cell and organism. There is definite standing ground for the hormesis hypothesis both evolutionarily and biophysically, but experimental evidence is yet to change official policies on this matter. Application of the LNT model has important radiation protection and general human health ramifications, and thus it is important that the matter be resolved.

ISSN: 0158-9938

Record 424 of 474

Author(s): De Francesco, S (De Francesco, S.); Tommasone, FP (Tommasone, F. Pascale); Cuoco, E (Cuoco, E.); Verrengia, G (Verrengia, G.); Tedesco, D (Tedesco, D.)

Title: Radon hazard in shallow groundwaters: Amplification and long term variability induced by rainfall

Source: SCIENCE OF THE TOTAL ENVIRONMENT, 408 (4): 779-789 JAN 15 2010

Abstract: Rn-222 concentrations have been determined with a RAD7 radon detector in shallow groundwaters of the Pietramelara Plain, north-western Campania, southern Italy, where pyroclastic deposits, along with recent stream alluvial sediments, come in contact with Mesozoic carbonate reservoirs. The aim of this study has been to study the annual variation of Rn-222 concentration in the shallow groundwaters, scarcely considered in the literature and of obvious relevance for radon hazard evaluation. Our results definitely show that Rn-222 levels are characterized by a clear annual periodicity, strictly related to rainfall and water table levels, with a pronounced difference between the dry and the wet season. In this last case with concentrations increasing up to two orders of magnitude (up to two times the lower threshold given in the Recommendation 2001/928/EURATOM for public waters). In relation to this, experimental field data will be presented to demonstrate that this variability is due to purely hydrological mechanisms, mainly rinse out and discharge that control leaching efficiency. The detected cycle (Radon Hydrological Amplification Cycle, RHAC) has been generalized for the Mediterranean Tyrrhenian climate. The marked and seasonally persistent amplification in Rn-222 levels poses the problem of evaluating the epidemiological risk brought up by this previously not yet reported mechanism. This mechanism, occurring in shallow groundwaters, very likely should strongly influence indoor radon levels via groundwater-soil-building exchange. (C) 2009 Elsevier B.V. All rights reserved.

ISSN: 0048-9697

DOI: 10.1016/j.scitotenv.2009.11.024

Record 425 of 474

Author(s): Celik, N (Celik, N.); Damla, N (Damla, N.); Cevik, U (Cevik, U.)

Title: Gamma ray concentrations in soil and building materials in Ordu, Turkey

Source: RADIATION EFFECTS AND DEFECTS IN SOLIDS, 165 (1): 1-10 2010

Abstract: The city of Ordu is in the Eastern Black Sea region of Turkey with a population of approximately 716,000. Presently there is no information available about radioactivity levels in Ordu soil and building materials. For this reason, activity concentrations in soil and building material samples collected from different sampling stations in Ordu were measured using gamma-ray spectrometry. In addition to natural radionuclides, Cs-137 was detected in the soil samples and the possible origins of this radionuclide were discussed. The activity concentrations of soil samples ranged from 13.4 to 151.7 Bq kg(-1) for Ra-226, from 14.3 to 98.5 Bq kg(-1) for Th-232, from 303 to 1107 Bq kg(-1) for K-40 and from 67.4 to 275.3 Bq kg(-1) for Cs-137. The mean concentrations of Ra-226, Th-232 and K-40 in selected building materials were 34.5, 26.9 and 378.4 Bq kg(-1), respectively. The results were compared with the reported data from different works. From the measurements, radium equivalent activity, terrestrial absorbed dose, annual effective dose rate, external hazard indices and internal hazard indices were calculated, and were found to be within the acceptable limits. The data presented in this study might be useful as a baseline data for future estimations of a population's exposure.

ISSN: 1042-0150

DOI: 10.1080/10420150903173270

Record 427 of 474

Author(s): Karpinska, M (Karpinska, M.); Mnich, Z (Mnich, Z.); Kapala, J (Kapala, J.); Szpak, A (Szpak, A.)

Title: The Evaluation of Indoor Radon Exposure in Houses

Source: POLISH JOURNAL OF ENVIRONMENTAL STUDIES, 18 (6): 1005-1012 2009

Abstract: In 2000-07 653 measurements of radon were acquired from houses in Podlasie Province, Poland. In dwelling parts of buildings, arithmetic weighted mean regarding location of the building equal to 72 Bq/m(3), which corresponded to 1.8 mSv of the effective dose. Statistically significant differences between radon concentrations in country and city houses were observed. Arithmetic mean of radon concentrations in dwelling parts of houses in rural areas was 111 Bq/m(3), while in the city it was 45 Bq/m(3). Correlation between radon concentrations in a house and its age was observed. The correlation coefficient was 0.3 at p<0.05.

ISSN: 1230-1485

Record 429 of 474

Author(s): Dubey, P (Dubey, P.); Ravikant, V (Ravikant, V.); Chakrapani, GJ (Chakrapani, G. J.)

Title: Strontium isotopic compositions in selected hot spring waters in the northwestern Himalaya

Source: HIMALAYAN GEOLOGY, 31 (1): 19-22 2010

Abstract: The present study deals mainly in presentation of data on dissolved Sr and Sr-87/Sr-86 ratios of selected hot spring and river waters in the Parbati and Beas valleys of Himachal Pradesh. The hot spring waters are characterized by highly radiogenic strontium and are more enriched in total dissolved strontium concentration as compared to the river waters. The results of this study imply that the numerous hot springs in the Himalayan region may play a significant role on the Himalayan river geochemistry.

ISSN: 0971-8966

Record 430 of 474

Author(s): Peterson, RN (Peterson, Richard N.); Santos, IR (Santos, Isaac R.); Burnett, WC (Burnett, William C.)

Title: Evaluating groundwater discharge to tidal rivers based on a Rn-222 time-series approach

Source: ESTUARINE COASTAL AND SHELF SCIENCE, 86 (2): 165-178 JAN 20 2010

Abstract: The natural flux of groundwater into coastal water bodies has recently been shown to contribute significant quantities of nutrients and trace metals to the coastal ocean. Groundwater discharge and hyporheic exchange to estuaries and rivers, however, is frequently overlooked though it often carries a distinctly different chemical signature than surface waters. Most studies that attempt to quantify this input to rivers use multiple geochemical tracers. However, these studies are often limited in their spatial and temporal extents because of the labor-intensive nature of integrating multiple measurement techniques. We describe here a method of using a single tracer, Rn-222, to rapidly characterize groundwater discharge into tidally-influenced rivers and streams. In less than one week of fieldwork, we determined that of six streams that empty into the Indian River Lagoon (IRL), Florida, three (Eau Gallie River, Turkey Creek, and Main Canal) did not receive substantial groundwater inputs, one canal (C-25 Canal) was dominated by groundwater exchange, and the remaining two (Sebastian River system and Crane Creek) fell somewhere in between. For more detailed discharge assessments, we focused on the Sebastian River system, a stratified tidal river estuary, during a relatively dry period (June) and a wet period July) in 2008. Using time-series 222Rn and current velocity measurements we found that groundwater discharge into all three branches of the Sebastian River increased by 1-2 orders of magnitude during the wetter period. The estimated groundwater flow rates were higher than those reported into the adjacent IRL, suggesting that discharge into these rivers can be more important than direct discharge into the IRL The techniques employed here should work equally well in other river/stream systems that experience significant groundwater discharge. Such assessments would allow area managers to quickly assess the distribution and magnitude of groundwater discharge nature into rivers over large spatial ranges. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 0272-7714

DOI: 10.1016/j.ecss.2009.10.022

Record 431 of 474

Author(s): Tondel, M (Tondel, Martin); Andersson, EM (Andersson, Eva M.); Barregard, L (Barregard, Lars)

Title: Time Trends in Indoor Radon Concentrations in Sweden

Source: EPIDEMIOLOGY, 20 (6): S146-S146 Suppl. S NOV 2009

ISSN: 1044-3983

Record 432 of 474

Author(s): Banerjee, KS (Banerjee, Kailas Sekhar); Sengupta, D (Sengupta, D.)

Title: Distribution pattern of the in situ terrestrial gamma radiation in uranium mineralized Singhbhum Shear Zone, Jharkhand and its correlation with local geology

Source: CURRENT SCIENCE, 98 (1): 76-81 JAN 10 2010

Abstract: Terrestrial gamma radiation is one of the important radiation exposures on the Earth's surface that results primarily from the three primordial radionuclides, viz. U, Th and K. The elemental concentrations of these elements in the Earth's crust could result in the anomalous variation of the terrestrial gamma radiation in the environment. The geology of a region plays an important role in distribution of these radioactive elements. In situ gamma radiation measurements in the soils and adjacent rock exposures along the Singhbhum Shear Zone, Eastern India were undertaken using a portable radiation survey meter. The results showed that the area has a reasonably close concordance with the geological formations, and the observed gamma radiation levels, since both geological features and mineralogical composition have good control on the terrestrial gamma radiation in the area. Correlation between the gamma level of soils and the underlying rocks was very poor. This suggests that the soils might not have originated from underlying rocks or might have different weathering mechanisms.

ISSN: 0011-3891

Record 433 of 474

Author(s): Utkin, VI (Utkin, V. I.); Yurkov, AK (Yurkov, A. K.)

Title: Radon as a tracer of tectonic movements

Source: RUSSIAN GEOLOGY AND GEOPHYSICS, 51 (2): 220-227 FEB 2010

Abstract: We suggest a model of radon emanation under compression or extension strain from a medium equivalent to rocks containing pores and cracks. The model is shown in several examples to be suitable for simulating the nucleation of rock bursts in deep mines and earthquakes. According to correlation of strain and radon measurements at the same sites, a relative strain change of n x 10(-7) corresponds to a 200% change of radon activity concentration. This high sensitivity means that radon data can be good tracers of tectonic movements. (C) 2010, V. S. Sobolev IGM, Siberian Branch of the RAS. Published by Elsevier B. V. All rights reserved.

ISSN: 1068-7971

DOI: 10.1016/j.rgg.2009.12.022

Record 435 of 474

Author(s): Steinitz, G (Steinitz, G.); Piatibratova, O (Piatibratova, O.)

Title: Radon signals in the Gavnunim intrusion, Makhtesh Ramon, Israel

Source: GEOPHYSICAL JOURNAL INTERNATIONAL, 180 (2): 651-665 FEB 2010

Abstract: High time resolution monitoring of radon, using alpha detectors is carried out in a massive and jointed syenite located in arid southern Israel. Monitoring, at a resolution of 15-min, is conducted in two boreholes at depths of 1.2 and 85-90 m, resulting in more then 10-yr long time-series. Systematic temporal variation patterns, manifesting large relative signals are composed primarily of annual (AR), multiday (MD), daily (DR) and subdaily (SDR) radon signals. Prominent periodic diurnal variation underlies the DR and probably also the SDR signals. Diurnal (S1; 24-hr) and semidiurnal (S2; 12-hr) constituents characterize the DR signal at 1.2 m, while diurnal constituents typical for gravity related periodicities (M2, O1) are absent. The amplitudes of the S1 and S2 constituents, calculated for consecutive 512-hr-long time intervals, exhibit a similar covarying annual pattern. The periodic DR signal is absent at 85 m depth. The peak time of SDR signals, occurring at this depth in some days, exhibits a 24- and 12-hr periodicity. Time offsets of hours are observed between time-series of the measured signal from the two levels. The lag, investigated for the decomposed MD signal, using consecutive 20-d-long time intervals, shows that the signal at depth systematically lags by around 9 hr the signal at the shallow level. Discrepancy of the patterns of the temporal variation in the time domain, and also in the frequency and time-frequency domains of the diurnal periodic components, indicates that atmospheric influence on the radon signal is insignificant even at a depth of 1.2 m. Combining this conclusion with the compound

interrelations occurring among the different radon signals suggests that other geophysical processes are driving the radon variation in the subsurface geogas. It is suggested that the significant S1 and S2 signatures, and their modulations, are imposed on the radon system by means of a direct link with solar radiation tide.

ISSN: 0956-540X

DOI: 10.1111/j.1365-246X.2009.04450.x

Record 436 of 474

Author(s): Fujiyoshi, R (Fujiyoshi, Ryoko); Haraki, Y (Haraki, Yukihide); Sumiyoshi, T (Sumiyoshi, Takashi); Amano, H (Amano, Hikaru); Kobal, I (Kobal, Ivan); Vaupotic, J (Vaupotic, Janja)

Title: Tracing the sources of gaseous components (Rn-222, CO2 and its carbon isotopes) in soil air under a cool-deciduous stand in Sapporo, Japan

Source: ENVIRONMENTAL GEOCHEMISTRY AND HEALTH, 32 (1): 73-82 FEB 2010

Abstract: Radon (Rn-222) and carbon dioxide were monitored simultaneously in soil air under a cool-temperate deciduous stand on the campus of Hokkaido University, Sapporo, Japan. Both Rn-222 and CO2 concentrations in soil air varied with atmospheric (soil) temperature in three seasons, except for winter when the temperature in soil air remained constant at 2-3A degrees C at depth of 80 cm. In winter, the gaseous components were influenced by low-pressure region passing through the observation site when the ground surface was covered with snow of similar to 1 m thickness. Carbon isotopic analyses of CO2 suggested that CO2 in soil air may result from mixing of atmospheric air and soil components of different origins, i.e. CO2 from contemporary soil organic matter and old carbon from deeper source, to varying degrees, depending on seasonal meteorological and thus biological conditions.

ISSN: 0269-4042

DOI: 10.1007/s10653-009-9266-1

Record 437 of 474

Author(s): Pene, P (Pene, Pierre); Masse, R (Masse, Roland)

Title: Health effects of outdoor and indoor air pollution

Source: BULLETIN DE L ACADEMIE NATIONALE DE MEDECINE, 193 (6): 1387-1415 JUN 2009

Abstract: Outdoor air pollution and health : despite the overall reduction in air pollution over the years, with the noteworthy exception of carbon dioxide, scientists agree that there remain plausible statistical relations between different atmospheric pollutants and the short-term and long-term risk of certain respiratory and cardiovascular diseases. Although the relative risks are weak, the universal nature of the exposure can incur considerable medical costs. The frequently expressed fear of synergy among pollutants appears unfounded, as the current marginal risk already results from an extremely complex mixture of pollutants whose concentrations have been decreasing for more than 30 years. Attention is currently focusing on the roles of ozone and fine particles. Better knowledge of fine particle origin, composition, size and potential toxic mechanisms is needed. Indoor air pollution and health : the possible medical consequences of exposure to the pollutants of room air is an emerging issue. Domestic exposure combines pollutants contained in outdoor air with those of the habitat itself Exposure can occur for up to 80 % of the day Recent investigations suggest that 9 % of homes are highly polluted and that 45 % are only slightly polluted, but epidemiological studies are still too rare to draw conclusions, except in the case of allergens, tobacco smoke, radon, and asbestos. Based on the intrinsic properties of toxins present in room air, one might expect irritant, immunotoxic, neurotoxic, carcinogenic and reprotoxic effects. Reference values are needed to assess associated health risks but are likely to be highly controversial.

ISSN: 0001-4079

Record 439 of 474

Author(s): Walsh, L (Walsh, Linda); Tschense, A (Tschense, Annemarie); Schnelzer, M (Schnelzer, Maria); Dufey, F (Dufey, Florian); Grosche, B (Grosche, Bernd); Kreuzer, M (Kreuzer, Michaela)

Title: The Influence of Radon Exposures on Lung Cancer Mortality in German Uranium Miners, 1946-2003

Source: RADIATION RESEARCH, 173 (1): 79-90 JAN 2010

Abstract: Extensive uranium extraction took place from 1946 until 1990 at the former Wismut mining

company in East Germany. A total of 58,987 male former employees of this company form the largest single uranium miners cohort that has been followed up for causes of mortality occurring from the beginning of 1946 to the end of 2003. The purpose of this study was to investigate and evaluate different forms of models for the radon exposure-related lung cancer mortality risk based on 3,016 lung cancer deaths and 2 million person years. Other exposure covariables such as occupational exposure to external gamma radiation, long-lived radionuclides, arsenic, fine dust and silica dust are available. The standardized mortality ratio for lung cancer is 2.03 (95% CI: 1.96; 2.10). The simple cohort excess relative risk (ERR/WLM) for lung cancer is estimated as 0.0019 (95% CI: 0.0016; 0.0022). The BEIR VI model produced risks similar to those obtained with a selected mathematically continuous ERR model for lung cancer. The continuous model is linear in radon exposure with exponential effect modifiers that depend on the whole range of age at median exposure, time since median exposure, and radon exposure rate. In this model the central estimate of ERR/WLM is 0.0054 (95% CI: 0.0040; 0.0068) for an age at median exposure of 30 years, a time since median exposure of 20 years, and a mean exposure rate of 3 WL. The ERR decreases by 5% for each unit of exposure-rate increase. The ERR decreases by 28% with each decade increase in age at median exposure and also decreases by 51% with each decade increase in time since median exposure. The method of determination of radon exposure (i.e., whether the exposures were estimated or measured) did not play an important role in the determination of the ERR. The other exposure covariables were found to have only minor confounding influences on the ERR/WLM for the finally selected continuous model when included in an additive way. (C) 2010 by Radiation Research Society

ISSN: 0033-7587

DOI: 10.1667/RR1803.1

Record 440 of 474

Author(s): Mokhtari, M (Mokhtari, Mohammad)

Title: Earthquake prediction activities and Damavand earthquake precursor test site in Iran

Source: NATURAL HAZARDS, 52 (2): 351-368 FEB 2010

Abstract: Iran has long been known as one of the most seismically active areas of the world, and it frequently suffers destructive and catastrophic earthquakes that cause heavy loss of human life and widespread damage. The Alborz region in the northern part of Iran is an active EW trending mountain belt of 100 km wide and 600 km long. The Alborz range is bounded by the Talesh Mountains to the west and the Kopet Dagh Mountains to the east and consists of several sedimentary and volcanic layers of Cambrian to Eocene ages that were deformed during the late Cenozoic collision. Several active faults affect the central Alborz. The main active faults are the North Tehran and Mosha faults. The Mosha fault is one of the major active faults in the central Alborz as shown by its strong historical seismicity and its clear morphological signature. Situated in the vicinity of Tehran city, this 150-km-long N100A degrees A E trending fault represents an important potential seismic source. For earthquake monitoring and possible future prediction/precursory purposes, a test site has been established in the Alborz mountain region. The proximity to the capital of Iran with its high population density, low frequency but high magnitude earthquake occurrence, and active faults with their historical earthquake events have been considered as the main criteria for this selection. In addition, within the test site, there are hot springs and deep water wells that can be used for physico-chemical and radon gas analysis for earthquake precursory studies. The present activities include magnetic measurements; application of methodology for identification of seismogenic nodes for earthquakes of M a parts per thousand yen 6.0 in the Alborz region developed by International Institute of Earthquake Prediction Theory and Mathematical Geophysics, IIEPT RAS, Russian Academy of Science, Moscow (IIEPT&MG RAS); a feasibility study using a dense seismic network for identification of future locations of seismic monitoring stations and application of short-term prediction of medium- and large-size earthquakes is based on Markov and extended self-similarity analysis of seismic data. The establishment of the test site is ongoing, and the methodology has been selected based on the IASPEI evaluation report on the most important precursors with installation of (i) a local dense seismic network consisting of 25 short-period seismometers, (ii) a GPS network consisting of eight instruments with 70 stations, (iii) magnetic network with four instruments, and (iv) radon gas and a physico-chemical study on the springs and deep water wells.

ISSN: 0921-030X

DOI: 10.1007/s11069-009-9375-2

Record 442 of 474

Author(s): Adrovic, F (Adrovic, Feriz); Kasic, A (Kasic, Amela); Kasumovic, A (Kasumovic, Amira); Tresnjo, Z (Tresnjo, Zejnil)

Title: Investigation of Radon in drinking of the North-Eastern region of Bosnia and Herzegovina

Source: TECHNICS TECHNOLOGIES EDUCATION MANAGEMENT-TTEM, 4 (2): 201-207 2009

Abstract: Some areas of the Tuzla region (B&H) suffer heavy problems with the shortage of quality drinking water. The only real long-term water resource in this region is the Lake Modrac, the largest accumulation lake in Bosnia and Herzegovina. Due to the fact that radon is soluble in water it can be transported by water to long distances. In cases of intake of waters rich in radon the most affected are sensitive cells within the abdomen and other internal organs. In order to satisfy the needs for drinking water, people are forced to excavate and drill wells. In area of the Tuzla region and the whole of B&H excavated wells are very frequent, and so are drilled wells lately, due to the more developed and cheaper technology for soil drilling. The activities in this area, likewise in the whole of B&H, are carried out in an unordered manner and without previously completed chemical and radiological analysis of soil and water samples. The University of Tuzla formed the Laboratory for detection of radon in all environments, and the researches displayed in this paper have been the first investigations of that kind in B&H. In this paper we presented the results of radon survey in drinking waters from excavated and chilled wells in area of the Tuzla region (North-Eastern region of B&H). The measurements were conducted over the period of one year (2006), so as to make it possible to monitor the variations of radon concentrations in dependence of the meteorological changes. These investigation works showed that radon concentration at most locations was significantly higher in drilled wells than in excavated wells. Mean values of radon concentration in the tested water samples ranged in the interval of 101-4200 Bq/m(3). The radon activity concentration was measured with the Alpha GAURD radon system (Genitron instruments-Frankfurt).

ISSN: 1840-1503

Record 443 of 474

Author(s): Nikolopoulos, D (Nikolopoulos, Dimitrios); Vogiannis, E (Vogiannis, Efstratios); Petraki, E (Petraki, Ermioni); Zisos, A (Zisos, Athanasios); Louizi, A (Louizi, Anna)

Title: Investigation of the exposure to radon and progeny in the thermal spas of Loutraki (Attica-Greece): Results from measurements and modelling

Source: SCIENCE OF THE TOTAL ENVIRONMENT, 408 (3): 495-504 JAN 1 2010

Abstract: Radon and progeny (Po-218, Pb-214, Bi-214 and Po-214) in thermal spas are well known radioactive pollutants identified for additional radiation burden of patients due to the activity concentration peaks which appear during bath treatment or due to drinking of waters of high radon content. This burden affects additionally the working personnel of the spas. The present paper has focused on the thermal spas of Loutraki (Attica-Greece). The aim was the investigation of the health impact for patients and working personnel due to radon and progeny. Attention has been paid to radon and progeny transient concentration peaks (for bath treatment) and to radon of thermal waters (both for bath treatment and drinking therapy). Designed experiments have been carried out, which included radon and progeny activity concentration measurements in thermal waters and ambient air. Additionally, published models for description of radon and progeny transient concentration peaks were employed. The models were based on physicochemical processes involved and employed non linear first order derivative mass balance differential equations which were solved numerically with the aid of specially developed computer codes. The collected measurements were analysed incorporating these models. Results were checked via non linear statistical tests. Predictions and measurements were found in close agreement. Non linear parameters were estimated. The models were employed for dosimetric estimations of patients and working personnel. The effective doses of patients receiving bath treatment were found low but not negligible. The corresponding doses to patients receiving potable treatment were found high but below the proposed international limits. It was found that the working personnel are exposed to considerable effective doses, however well below the acceptable limits for workers. It was concluded that treatment and working in the Loutraki spas leads to intense variations of radon and progeny and consequently additional health impact both to patients and working personnel. (C) 2009 Elsevier B.V. All rights reserved.

ISSN: 0048-9697

DOI: 10.1016/j.scitotenv.2009.09.057

Record 444 of 474

Author(s): Tommasino, L (Tommasino, L.); Tommasino, MC (Tommasino, M. C.); Viola, P (Viola, P.)

Title: Radon-film-badges by solid radiators to complement track detector-based radon monitors

Source: RADIATION MEASUREMENTS, 44 (9-10): 719-723 Sp. Iss. SI OCT-NOV 2009

Abstract: Existing passive radon monitors, based on track detectors, present many shortcomings, such as a limited response sensitivity for one-week-indoor measurements and a limited response linearity for the assessment of large radon exposures indoors, in thermal spa, in caves, and in soil. Moreover, for in-soil measurements these monitors are too bulky and are often conducive to wrong results. For what concerns the radon-in-water measurements, they are just not suitable. A new generation of passive radon monitors is introduced in this paper, which are very similar to the compact badges used in neutron- and gamma-dosimetry and will be referred to as radon-film-badges. These film-badges are formed by thin-film radiators with suitable radon-sorption characteristics, facing track detectors, The key strategy adopted for these radiators is to exploit an equilibrium type of radon sorption in solids. Even though this new generation of passive monitors is at its infancy, it appears already clear that said monitors make it finally possible to overcome most of the shortcomings of existing passive radon monitors. These devices are uniquely simple and can be easily acquired by any existing radon service to complement their presently used passive radon monitors with little or no effort. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.013

Record 445 of 474

Author(s): Ibrahimi, ZF (Ibrahimi, Z. -F.); Howarth, CB (Howarth, C. B.); Miles, JCH (Miles, J. C. H.)

Title: Sources of error in etched-track radon measurements and a review of passive detectors using results from a series of radon intercomparisons


Abstract: Etched-track passive radon detectors are a well established and apparently simple technology. As with any measurement system, there are multiple sources of uncertainty and potential for error. The authors discuss these as well as good quality assurance practices. Identification and assessment of sources of error is crucial to maintain high quality standards by a measurement laboratory. These sources can be found both within and outside the radon measurement laboratory itself. They can lead to changes in track characteristics and ultimately detector response to radon exposure. Changes don't just happen during etching, but can happen during the recording or counting of etched-tracks (for example ageing and fading effects on track sensitivity, or focus and image acquisition variables). Track overlap means the linearity of response of detectors will vary as exposure increases. The laboratory needs to correct the calibration curve due to this effect if it wishes to offer detectors that cover a range of exposures likely to be observed in the field. Extrapolation of results to estimate annual average concentrations also has uncertainty associated with it. Measurement systems need to be robust, reliable and stable. If a laboratory is not actively and constantly monitoring for anomalies via internal testing, the laboratory may not become aware of a problem until some form of external testing occurs, eg an accreditation process, performance test, interlaboratory comparison exercise or when a customer has cause to query results. Benchmark standards of accuracy and precision achievable with passive detectors are discussed drawing on trends from the series of intercomparison exercises for passive radon detectors which began in 1982, organised by the National Radiological Protection Board (NRPB), subsequently the Health Protection Agency (HPA). (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.009

Record 446 of 474

Author(s): Nikezic, D (Nikezic, D.); Krstic, D (Krstic, D.); Savovic, S (Savovic, S.)

Title: Response of diffusion chamber with LR115 detector and electret to radon and progeny


Abstract: Cylindrical diffusion chamber for radon measurement equipped with nuclear track detector (LR115) and electret, was considered in this work. Electrets were used to attract positively charged radon progeny created by radon decay inside a chamber. Sensitivity of such setup has been determined for different distances between electret and LR115 detector. A possibility of progeny separation was observed, due to the existence of upper energy detection limit of LR115. Different geometries of detector

and electret were tested in order to optimize this kind of device. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.09.003

Record 447 of 474

Author(s): Hulber, E (Hulber, E.)

Title: Overview of PADC nuclear track readers. Recent trends and solutions


Abstract: The development of automated track readers dates back to the first routine dosimetry applications of solid state nuclear track detectors. Many research-laboratory track readers and a few commercial systems were introduced in the past 25 years. The traditional application area for high-throughput track readers is radon testing in buildings and fast neutron dosimetry. The latter application, in particular, has considerably increased the need for efficient polyallyldiglycol carbonate (PADC) track reader systems with high throughput. The paper provides an overview of recent trends in the development of high-throughput PADC track readers and it gives a glimpse into the practice of designing this category of devices. A general overview is provided of the technical aspects relating to the optics, the hardware and the track recognition approaches. Ultimate theoretical limits in the performance as well as promising new approaches are addressed. Requirements and practical solutions are illustrated with reference to a commercially available system. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.097

Record 448 of 474

Author(s): Moreno, V (Moreno, V.); Bach, J (Bach, J.); Baixeras, C (Baixeras, C.); Font, L (Font, Ll.)

Title: Characterization of blowholes as radon and thoron sources in the volcanic region of La Garrotxa, Spain


Abstract: In the volcanic region of La Garrotxa there are natural holes in the soil from which a flow of air can reach the outdoor/indoor environment. In a previous study, these holes (called blowholes) have been found to have a big influence on indoor radon levels in a couple of houses, This finding triggered the interest to characterize these blowholes as radon/thoron sources. In this work, a total of 26 holes have been identified and characterized by geological field observations and by measuring their dimensions, air speed, temperature, humidity, and radon and thoron concentrations. Radon has been measured with passive (Makrofol) and active detectors (monitors PRASSI and RAD 7, being the latter used also to measure thoron). One of the indoor blowholes has been studied in detail and important temporal variations have been found, showing that radon levels are clearly correlated with the soil-outdoor temperature difference. There is not a significant radiological risk for the inhabitants and workers of the studied homes and workplaces with indoor blowholes. However, taking into account that in warm seasons buildings with blowholes in pyroclastic materials from volcanoes or in volcanic scoria under a compact lava flow may have high indoor radon levels (up to 1.5 kBq m(-3)) we conclude that volcanic regions with similar geological features and with presence of blowholes should be considered as areas with a potential radon/thoron radiological risk. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.008

Record 449 of 474

Author(s): Walia, V (Walia, Vivek); Lin, SJ (Lin, S. J.); Hong, WL (Hong, W. L.); Fu, CC (Fu, C. C.); Yang, TF (Yang, T. F.); Wen, KL (Wen, K. L.); Chen, CH (Chen, C. -H.)

Title: Continuous temporal soil-gas composition variations for earthquake precursory studies along Hsincheng and Hsinhua faults in Taiwan


Abstract: Measurement of soil-gas emissions along active zones is demonstrated as a geochemical tool to identify and monitor tectonic activity in the region. The present study is proposed to investigate geochemical variations of soil-gas composition in the vicinity of geologic fault zones of Hsincheng Fault

and the Hsinhua Fault within the Hsinchu and Tainan areas, respectively, and to determine the influence of such formations on enhanced concentrations of different gases in soil to monitor the tectonic activity in the region. To carry out the present investigation temporal variation in soil-gases compositions was measured at continuous earthquake monitoring station established along the above said faults. Observations have shown potential precursory signals for some major earthquakes in the region. Results have shown that Hsinhua and Hsincheng Faults have different tectonic settings. Hsinhua soil-gas variations show precursory signals for earthquakes occurring in south or south eastern part of Taiwan, whereas for Hsincheng Fault most of soil-gas variation precursory signals were recorded for the earthquakes that occurred along Okinawa Trough and Ryukyu Trough. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.010

Record 450 of 474

Author(s): Fu, CC (Fu, Ching-Chou); Yang, TF (Yang, Tsanyao Frank); Walia, V (Walia, Vivek); Liu, TK (Liu, Tsung-Kwei); Lin, SJ (Lin, Shih-Jung); Chen, CH (Chen, Cheng-Hong); Hou, CS (Hou, Chin-Shoun)

Title: Variations of soil-gas composition around the active Chihshang Fault in a plate suture zone, eastern Taiwan


Abstract: The active Chihshang Fault in the Longitudinal Valley of eastern Taiwan is part of the suture boundary between the Eurasian plate and Philippine Sea plate. Soil-gases collected systematically across the Chihshang Fault reveal anomalies at specific positions that coincide with the geological, geophysical and topographical characteristics of faults/fractures in studied area. An automatic soil radon monitoring station was set up at the fault zone, at the same place as existing monitoring wells and creep meter monitoring. Some anomalous high soil radon concentrations were observed, usually a few days before local earthquakes. However, other anomalies could not be related to any earthquake event, and may be related to surface creeping of the fault as revealed from the creep meter monitoring in the studied area. In addition, heavy rainfall induced significant increase of soil radon concentrations which may be related to the rapid surface creep that was triggered by the heavy rain in a short time. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.095

Record 451 of 474

Author(s): Font, L (Font, Ll.)

Title: On radon surveys: Design and data interpretation


Abstract: Though open to all conference participants, this refresher lecture is addressed mainly to young students that start their research on radon monitoring. I cover the most relevant aspects that have to be taken into account when carrying out a radon survey: how to design it as a function of the objectives of the survey, which are the most common different strategies to distribute and collect the dosimeters, and which is the quality assurance programme that a radon laboratory should take into account. Special emphasis is put on the data analysis and on the interpretation of the results obtained. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.044

Record 452 of 474

Author(s): Udovicic, V (Udovicic, V.); Grabez, B (Grabez, B.); Dragic, A (Dragic, A.); Banjanac, R (Banjanac, R.); Jokovic, D (Jokovic, D.); Panic, B (Panic, B.); Joksimovic, D (Joksimovic, D.); Puzovic, J (Puzovic, J.); Anicin, I (Anicin, I.)

Title: Radon problem in an underground low-level laboratory


Abstract: The low-level gamma-ray spectroscopy as well as the investigation of rare nuclear processes require not only low, but also constant levels of relevant background radiations. In underground

laboratories dedicated to this type of measurements, one of the main and hard to control sources of unwanted radiation is the radioactive gas radon. It is well-known that radon concentration varies daily and seasonally, primarily due to the variation of atmospheric parameters. This introduces unwanted and hard to evaluate systematic uncertainties in long-term low-level measurements. In this paper, the system for radon reduction in the underground Low-Background Laboratory for Nuclear Physics at the Institute of Physics in Belgrade is presented in some detail. The laboratory exists for ten years and different measurements of radon concentration were carried out during this period. The indoor radon measurements are performed using nuclear track detectors (type CR-39 and LR-115) for long-term measurements and the commercially available radon monitor for short-term measurements. In this work we present the results of these measurements for the period 2003-2008. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.038

Record 453 of 474

Author(s): Calamosca, M (Calamosca, M.); Penzo, S (Penzo, S.)

Title: A new CR-39 nuclear track passive thoron measuring device


Abstract: Rn-220 monitoring in dwellings and in workplaces is seldom performed, both because usually the associated risk is considered negligible and for the difficulties of properly measuring it As a consequence the. state of art of thoron measurements by using solid-state nuclear track detectors shows a significant la g compared with radon. However the demand of determining the thoron contribution to natural dose assessment is worldwide increasing, and in the presence of some building materials as tuff, should be mandatory. To tackle this problem, the ENEA Radon Measuring Service has developed a dose evaluation 22 procedure based on the measurement of the Rn-220 concentration at a standard distance from the wall, by using a new (patent pending) CR-39 alpha track detector thoron passive device (ATD-TnPD), coupled to our own radon passive device (ATD-RnPD). The two devices are geometrically similar and their responses were extensively evaluated to optimise the uncertainty of the thoron measurement. This paper depicts the prime features of the new device, and the introduced changes aimed at reducing the device's equilibrium time constant from 20.8 min to 3.1 min. Since no reliable thoron calibration facility has resulted available up to now, we had to state the ATD-TnPD's sensitivity parameter by performing the calibration step by our own. A closed circuit thoron exposure facility was set up to provide thoron exposures at 3 different levels. The exposed detectors were chemically etched at 7 increasing etching times to study the relationship between sensitivity and etching conditions, so to optimise the detector response and the measurement uncertainty. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.043

Record 454 of 474

Author(s): Shweikani, R (Shweikani, R.); Raja, G (Raja, G.)

Title: Radon exhalation from some finishing materials frequently used in Syria


Abstract: 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 mu Sv and 35 mu Sv from radon and gamma respectively. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.034

Record 455 of 474

Author(s): Bochicchio, F (Bochicchio, F.); Ampollini, M (Ampollini, M.); Tommasino, L (Tommasino, L.); Sorimachi, A (Sorimachi, A.); Tokonami, S (Tokonami, S.)

Title: Sensitivity to thoron of an SSNTD-based passive radon measuring device: Experimental evaluation and implications for radon concentration measurements and risk assessment


Abstract: Passive devices based on SSNTDs (Solid State Nuclear Track Detectors) are widely used to measure radon concentration in indoor air. These devices often include a filter or other types of barrier to prevent the sampling of decay products. However, such filters and barriers have different degrees of effectiveness in preventing thoron from entering the sensitive volume of the passive device, with the result that in some cases the measured track density is affected by thoron concentration, especially if devices are placed very close to walls exhalating thoron. This can produce a bias in epidemiological studies aimed to evaluate the risk from radon. A radon measuring device with LR 115 detectors enclosed in a heat-sealed 35 mu m low density (0.92 g/cm(3)) polyethylene bag has been largely used in Italy and other countries. Moreover, it was used in an epidemiological study carried out in an Italian region where a large fraction of dwellings are built with materials containing high thorium concentration and exhalating a remarkable quantity of thoron. The sensitivity to thoron of this device was experimentally evaluated by exposing groups of 10 devices each in the NIRS (Japan) radon/thoron chamber to three different thoron exposures, i.e. 500, 1000 and 2000 kBq/m(3) h. The sensitivity to thoron of these devices resulted to be about 0.4% of their sensitivity to radon. In conclusion, radon concentrations measured with the evaluated passive device are not significantly affected by the presence of thoron. Therefore both the distribution of radon concentration obtained in the national and regional surveys in Italy and the risk of lung cancer from radon exposure in dwellings, as estimated in an epidemiological study carried out in an Italian region with high radon and thoron, have not been biased by the presence of thoron. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.090

Record 456 of 474

Author(s): Espinosa, G (Espinosa, G.); Golzarri, JI (Golzarri, J. I.); Ponciano-Rodriguez, G (Ponciano-Rodriguez, G.); Gaso, MI (Gaso, M. I.); Mena, M (Mena, M.); Segovia, N (Segovia, N.); Vazquez-Lopez, C (Vazquez-Lopez, C.); Sajo-Bohus, L (Sajo-Bohus, L.)

Title: Population vulnerability due to the exposure to radon and airborne particulate matter (PM10), in Mexico City


Abstract: Exposure to indoor radon and suspended particulate matter (SPM) is considered a high risk in lung cancer aetiology. In this paper indoor radon and SPM concentration measurements and their correlations, associated with lung cancer cases are given. Mexico City suffers high concentration of SPM as well as other photochemical pollutants such as ozone. During the last decade in Mexico City, radon and SPM have been monitored. The indoor radon measurements were done using the Nuclear Track Methodology, basically the close-end-cup device with polyallyldiglycol carbonate as detector material, followed of an established chemical etching protocol, and automatic digital image analyzer system for counting. SPM size and concentration were obtained from monitoring stations located along the city. The results show that the central-north part of Mexico City has a large concentration of SPM and the vulnerable population (older than 65 years and younger than 14 years) is located essentially in the same region. In this area, a large number of lung cancer cases were found, even if indoor radon levels were below the recommended limits. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.023

Record 457 of 474

Author(s): Gusain, GS (Gusain, G. S.); Prasad, G (Prasad, Ganesh); Prasad, Y (Prasad, Yogesh); Ramola, RC (Ramola, R. C.)

Title: Comparison of indoor radon level with radon exhalation rate from soil in Garhwal Himalaya


Abstract: The assessment of radiological risk related to inhalation of radon and radon progeny is based mainly on the integrated measurement of radon in both indoor and outdoor environments. The exhalation of radon from the earth crust and building materials forms the main source of radon in indoor

environment. In this comparative study, the indoor radon level was measured using twin cup dosimeter in different dwellings of Garhwal Himalayas. Soil samples were collected simultaneously from different geological formations of the same area for laboratory measurement of radon exhalations rate. The radon exhalation rate was measured in the laboratory using LR-115 type 11 plastic track detectors. The indoor radon concentrations in this study area were found to vary from 13 +/- 3 Bq/m(3) to 178 +/- 8 Bq/m(3) with an average of 61 +/- 5 Bq/m(3) while thoron concentration was found to vary 9 2 Bq/m(3) to 94 6 Bq/m(3) with an average of 33 +/- 3 Bq/m(3), The radon exhalation rate was found to vary from (0.43 +/- 0.05) x 10(-5) Bq kg(-1) h(-1) to (20.10 +/- 0.11) x 10(-5) Bq kg(-1) h(-1) with an average of (1.95 0.10) x 10(-5) Bq kg(-1) h(-1). The detail significance of this study is discussed in radiation protection point of view. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.033

Record 458 of 474

Author(s): Antignani, S (Antignani, S.); Bochicchio, F (Bochicchio, F.); Ampollini, M (Ampollini, M.); Venoso, G (Venoso, G.); Bruni, B (Bruni, B.); Innamorati, S (Innamorati, S.); Malaguti, L (Malaguti, L.); Stefano, A (Stefano, A.)

Title: Radon concentration variations between and within buildings of a research institute


Abstract: Radon concentration in indoor air has been measured in many countries in a large number of buildings mainly in houses but also in apartments and workplaces - mostly as a result of the application of radon policies and regulation requirements. However, few systematic analyses are available on radon concentration variations within buildings and between close buildings, especially as regards workplaces; such variations can have a significant impact on indoor radon exposure evaluation, and ultimately on the assessment of the dose from radon received by workers. Therefore, a project was started in 2006 aimed to Study the spatial variation of radon concentration among and within about 40 buildings of the Istituto Superiore di Sanita (ISS), a research institute of public health located in Rome over a small area of less than 1 km(2). Nuclear track detectors (CR-39) were used to measure radon concentration for two consecutive six-month periods, in more than 700 rooms of the surveyed buildings. The paper describes the project in detail and preliminary results regarding 558 rooms in 29 buildings. Coefficient of variation (CV) was calculated as a measure of relative variation of radon concentration between buildings, between floors, and between rooms on the same floor. The CV between buildings resulted quite high (88%), a lower CV (42%) was found for variation between floors, whereas room-to-room CV on the same floor ranged from 25% at first floor level to 48% at basement level. Floor mean ratios, with ground floor as the reference level, were calculated for each building in order to study the correlation between radon concentration and floor levels. Although no clear trend was observed, the average basement/ground floor ratio of radon concentrations resulted about 2.0, whereas the average sixth floor/ground floor ratio of radon concentrations was 0.5. Some discussion on the potential impact of the results of this study on policies and radon regulations are also included in the paper. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.074

Record 459 of 474

Author(s): Omori, Y (Omori, Yasutaka); Tohbo, I (Tohbo, Izumi); Nagahama, H (Nagahama, Hiroyuki); Ishikawa, Y (Ishikawa, Yoichi); Takahashi, M (Takahashi, Masato); Sato, H (Sato, Hiroaki); Sekine, T (Sekine, Tsutomu)

Title: Variation of atmospheric radon concentration with bimodal seasonality


Abstract: Atmospheric radon (Rn-222) concentration has been measured on the Oshika Peninsula, northeastern Japan, since July 2005 to assess fluctuations of natural gamma-ray dose rate. The radon concentration shows a typical diurnal cycle with a minimum in daytime and a maximum in nighttime generated by the different strength in atmospheric convection, which is well observed in the world. On seasonal time scale, monthly change of the daily minimums has a monomodal seasonality with a maximum in winter and a minimum in summer, while monthly changes of the daily averages and maximums exhibit a bimodal one with maximum both in winter and summer. The origins of air masses

arriving to the measuring site characterized by the Asian monsoonal cycle appear to explain the monomodal seasonality rather than the bimodal one. In addition, the atmospheric stability is not strong enough to cause the radon increase in summer. These results suggest that the bimodal cycle is possibly decomposed of two phases: one is attributed to the seasonal difference in radon inflow by atmospheric circulation and the other in radon exhalation from the earth surface. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.077

Record 460 of 474

Author(s): Espinosa, G (Espinosa, G.); Golzarri, JI (Golzarri, J. I.); Angeles, A (Angeles, A.); Griffith, RV (Griffith, R. V.)

Title: Nationwide survey of radon levels in indoor workplaces in Mexico using Nuclear Track Methodology


Abstract: This report presents the preliminary results of an indoor workplace radon survey conducted during 2006-2007. Monitoring was carried out in 24 of the 32 federal entities of Mexico, incorporating 26 cities and 288 locations. The area monitored was divided into 8 regions for the purposes of the study: Chihuahua (a state with uranium mines), North-Central, South-Central, Southeast, South, Northeast, Northwest, and West. These regions differ in terms of geographic and geological characteristics, climate, altitude, and building materials and architectonic styles. Nuclear Track Methodology (NTM) was employed for the survey, using a passive closed-end cup device with Poly Allyl Diglycol Carbonate (PADC), known by its trade name CR-39 (Lantrack (R)), as detector material. Well-established protocols for making continuous indoor radon measurements were followed, including one-step chemical etching in a 6.25 M KOH solution at 60 +/- 1 degrees C with an etching time of 18 h. The track densities were determined with an automatic digital system at the Instituto de Fisica de la Universidad Nocional Autonoma de Mexico (IFUNAM) (Physics Institute of the National Autonomous University of Mexico), and calibrated in facilities at the Oak Ridge National Laboratory (ORNL). The importance of this survey lies in the fact that it represents the first time a nationwide survey of radon levels in indoor workplaces has been carried out in Mexico. Mean indoor radon levels from continuous measurements taken during and after working hours ranged from 13 Bq m(-3) (the lower limit of detection) to 196 Bq m(-3). Analogous official controls or regulations for radon levels in indoor workplaces do not exist in Mexico. The Survey described here contributes to knowledge of the natural radiological environment in workplaces, and will aid the relevant authorities in establishing appropriate regulations. The survey was made possible by the efforts of both a private institutions and the Dosimeter Application Project of the IFUNAM. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.035

Record 461 of 474

Author(s): Abou-Khalil, R (Abou-Khalil, R.); Michielsen, N (Michielsen, N.); Della-Negra, S (Della-Negra, S.); Nourreddine, A (Nourreddine, A.); Baussan, E (Baussan, E.)

Title: Electric charge spectrum of recoiling Po-218


Abstract: The chemical and physical properties of a radioactive nanometric aerosol are important in determining its behaviour in indoor atmospheres and play a major part in determining its potential health effects. In a well defined experimental system, mass spectrometry coupled to the Time-of-Flight technique, we measured the electric charge of Po-218 at the end of its recoil path. The charge distribution of the recoiling Po-218 is mainly neutral and singly charged with a very small multicharged fraction. In case of radon progeny embedded in solid matter this one can play a major role in the surface ionisation processes versus electron and ion emission induced by the passage of the alpha recoils through the surface. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.073

Record 462 of 474

Author(s): Carelli, V (Carelli, V.); Bianco, V (Bianco, V.); Cordedda, C (Cordedda, C.); Ferrigno, G

(Ferrigno, G.); Carpentieri, C (Carpentieri, C.); Bochicchio, F (Bochicchio, F.)

Title: A national survey on radon concentration in underground inspection rooms and in buildings of a telephone company: methods and first results


Abstract: A national survey has been carried out to measure radon concentration in a large sample of Telecom-Italia small underground inspection rooms, which form a particularly dense net in urban areas. Measuring radon in such underground places is interesting both for a possible contribution to radon mapping activities and to evaluate workers exposures. Radon concentration was also measured in Telecom buildings (i.e. buildings housing plant equipment, including telephone switches, often also offices, etc.) close and partially connected to the selected inspection rooms. The methodology and the first results of the survey related to the first year of measurements, fora total of 1438 inspection rooms and 1414 Telecom buildings, are reported. Radon concentration was measured with passive devices containing CR-39 detectors for about 12 consecutive months, in order to average seasonal variations. In underground inspection rooms, measured radon concentration reached values up to about 44,000 Bq/m(3), with a regional median ranging from about 90 Bq/m(3) up to about 1600 Bq/m(3). In Telecom buildings, the regional median concentration ranged from 13 Bq/m(3) to 174 Bq/m(3). These results show that radon concentration in underground inspection rooms can reach very high values, whereas medians in monitored buildings are generally lower than those measured in dwellings in a representative national survey. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.085

Record 463 of 474

Author(s): Bochicchio, F (Bochicchio, F.); Ampollini, M (Ampollini, M.); Antignani, S (Antignani, S.); Bruni, B (Bruni, B.); Quarto, M (Quarto, M.); Venoso, G (Venoso, G.)

Title: Results of the first 5 years of a study on year-to-year variations of radon concentration in Italian dwellings


Abstract: Radon concentration in air is subject to significant variations at different time scales, owing to several factors. In general, the shorter the time period considered, the larger the variations in radon concentration, e.g., day-to-day variations are usually higher than month-to-month variations. An average over 12 consecutive months is generally considered the best estimate of the long-term average radon concentration. Due to practical reasons, however, very few data are available on year-to-year variations. Year-to-year variations can have quite a relevant impact on radon policies and on the assessment of health risks from exposures to radon. Therefore, a project was started in 1996 aimed to evaluate year-to-year variations in a sample of dwellings. Systematic radon measurements have been made with LR 115 based radon detectors (closed type) in the living room and one bedroom of a sample of dwellings in Rome (Italy). The analysis of the results of the first five consecutive years of measurements, regarding the 76 dwellings included in the final analysis, showed relatively low year-to-year variations, with a median coefficient of variation of 14% (range 3%-42%), smaller than that observed in studies from other European countries. Therefore, in the analyzed sample, 12-month measurements can be considered a good estimate of the average radon concentration, at least within a 5-year period. This is quite important for radon regulations and policies, e.g. annual measurements could be recommended and repetition of radon measurements could not be necessary within periods of 5 years. Moreover, the impact of the observed year-to-year variations on the lung cancer risk estimated in the Italian epidemiological study is expected to be not high, if variations on periods up to about 30 years can be assumed similar to those observed in this study. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1350-4487

DOI: 10.1016/j.radmeas.2009.10.088

Record 465 of 474

Author(s): Doi, K (Doi, Kazutaka); Tokonami, S (Tokonami, Shinji); Yonehara, H (Yonehara, Hidenori); Yoshinaga, S (Yoshinaga, Shinji)

Title: A Simulation Study of Radon and Thoron Discrimination Problem in Case-Control Studies

Source: JOURNAL OF RADIATION RESEARCH, 50 (6): 495-506 NOV 2009

Abstract: In most countries, radon is the dominant contributor among natural radiation sources to the

radiation exposure dose of the general population. Numerous case-control studies of residential radon and lung can cer have been conducted using passive radon (Rn-222) detectors. These Studies showed that radon may increase lung cancer risk, but most of: them did not show a significant risk. Recently it was shown that the readings of passive radon detectors that do not employ thoron (Rn-220) discrimination techniques are affected by thoron. Therefore, we conducted a simulation Study to evaluate the possible effect of thoron interference on the estimation of radon-related lung cancer risk. Various assumptions were made based oil the number of cases, matching ratio, baseline risk, true radon-related risk, distribution of: radon and thoron concentrations, correlation between radon and thoron, and radon detectors. The results Suggested that in certain circumstances thoron interference in radon measurements resulted in an approximately 90% downward bias. In addition, the magnitude of the bias increased as the geometric mean and geometric standard error of radon concentration decreased and those of thoron increased. In order to resolve this problem, it is necessary to use passive radon detectors with thoron discrimination techniques in epidemiological studies.

ISSN: 0449-3060

DOI: 10.1269/jrr.09054

Record 466 of 474

Author(s): Ur-Rahman, S (Ur-Rahman, Saeed); Rafique, M (Rafique, Muhammad); Matiullah (Matiullah); Anwar, J (Anwar, Javaid)

Title: Indoor Radon Concentrations and Assessment of Doses in Four Districts of the Punjab Province - Pakistan

Source: JOURNAL OF RADIATION RESEARCH, 50 (6): 529-535 NOV 2009

Abstract: Seasonal indoor radon measurement studies have been carried Out in four districts, namely, Jhelum, Chakwal, Rawalpindi and Attock of the Punjab Province. In this regard, CR-39 based detectors were installed in bedrooms, drawing rooms and kitchens of 40 randomly selected houses in each district. After exposing to radon in each season, CR-39 detectors were etched in 6M NaOH at 80 degrees C and counted Under all optical microscope. Indoor radon activity concentrations in the houses Surveyed ranged from 15 +/- 4 to 176 +/- 7 Bq m(-3) with an overall average value of 55 +/- 31 Bq m(-3). The observed annual average values are greater than the world average of 40 Bq m(-3). Maximum, indoor radon concentration levels were observed in winter season whereas minimum levels were observed in Summer season. None of the measured radon concentration value exceeded the action level of 200-400 Bq m(-3). The season/annual ratios for different type of dwellings varied from 0.87 +/- 0.93 to 1.14 +/- 1.10. The mean annual estimated effective dose received by the residents of the studied area was found to be 1.39 +/- 0.78 mSv. The annual estimated effective dose is less than the recommended action level (3-10 mSv).

ISSN: 0449-3060

DOI: 10.1269/jrr.08116

Record 467 of 474

Author(s): Plastino, W (Plastino, Wolfango); Povinec, PP (Povinec, Pavel P.); De Luca, G (De Luca, Gaetano); Doglioni, C (Doglioni, Carlo); Nisi, S (Nisi, Stefano); Ioannucci, L (Ioannucci, Luca); Balata, M (Balata, Marco); Laubenstein, M (Laubenstein, Matthias); Bella, F (Bella, Francesco); Coccia, E (Coccia, Eugenio)

Title: Uranium groundwater anomalies and L'Aquila earthquake, 6th April 2009 (Italy)

Source: JOURNAL OF ENVIRONMENTAL RADIOACTIVITY, 101 (1): 45-50 JAN 2010

Abstract: Monitoring of chemical and physical groundwater parameters has been carried out worldwide in seismogenic areas with the aim to test possible correlations between their spatial and temporal variations and strain processes. Uranium (U) groundwater anomalies were observed during the preparation phases of the recent L'Aquila earthquake of 6th April 2009 in the cataclastic rocks near the overthrust fault crossing the deep underground Gran Sasso National Laboratory. The results suggest that U may be used as a potential strain indicator of geodynamic processes occurring before the seismic swarm and the main earthquake shock. Moreover, this justifies the different radon patterns before and after the main shock: the radon releases during and after the earthquake are much than more during the preparatory period because the process does not include only the microfracturing induced by stress-strain activation, but also radon increases accompanying groundwater U anomalies. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 0265-931X

DOI: 10.1016/j.jenvrad.2009.08.009

Record 468 of 474

Author(s): Abo-Elmagd, M (Abo-Elmagd, M.); Soliman, HA (Soliman, H. A.); Salman, KA (Salman, Kh. A.); El-Masry, NM (El-Masry, N. M.)

Title: Radiological hazards of TENORM in the wasted petroleum pipes

Source: JOURNAL OF ENVIRONMENTAL RADIOACTIVITY, 101 (1): 51-54 JAN 2010

Abstract: Disposal petroleum pipes containing sludge and scale as a technically enhanced natural occurring radioactive material (TENORM) leads to internal and external radiation hazards and then a significant radiation dose to the workers. In order to contribute to a future waste management policy related to the presence of TENORM in the disposal sites of wasted petroleum pipes, scale and sludge as TENORM wastes are collected form these disposal pipes for radiometric analysis. These pipes are imported from onshore oilfields at south Sinai governorate, Egypt. The highest mean Ra-226 and Ra-228 concentrations of 519 and 50 kBq/kg respectively, were measured in scale samples. Sludge lies within the normal range of radium concentration. The average absorbed dose caused by the exposure to the wasted pipes equal to 4.09 mu Gy h(-1) from sludge and 262 mu Gy h(-1) from scale. This is much higher than the acceptable level of 0.059 mu Gy h(-1). Due to radon inhalation, important radon related parameters are calculated which advantage in internal dose calculation. Fairly good correlation between real radium content and radon exhalation rate for sludge samples is obtained. The hazards from sludge come from its high emanation power for radon which equal to 3.83%. The obtained results demonstrate the need of screening oil residues for their radionuclide content in order to decide about their final disposal. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 0265-931X

DOI: 10.1016/j.jenvrad.2009.08.016

Record 470 of 474

Author(s): Alabdula'aly, AI (Alabdula'aly, Abdulrahman I.); Maghrawy, HB (Maghrawy, Hamed B.)

Title: Radon emanation from radium specific adsorbents

Source: WATER RESEARCH, 44 (1): 177-184 JAN 2010

Abstract: Pilot studies were undertaken to quantify the total activity of radon that is eluted following no-flow periods from several Ra-226 adsorbents loaded to near exhaustion. The adsorbents studied included two types of barium sulphate impregnated alumina (ABA-8000 and F-1) and Dowex MSC-1 resin treated by either barium hydroxide or barium chloride. In parallel, radium loaded plain activated aluminas and Dowex MSC-1 resin were similarly investigated. The results revealed that radon was quantitatively eluted during the first few bed volumes of column operation after no-flow periods. Although similar radon elution profiles were obtained, the position of the radon peak was found to vary and depended on the adsorbent type. Radon levels up to 24 and 14 kBq dm(-3) were measured after a rest period of 72 h from radium exhausted Dowex MSC-1 treated with barium chloride and F-1 impregnated alumina with barium sulphate, respectively. The eluted radon values measured experimentally were compared to those calculated theoretically from accumulated radium quantities for the different media. For plain adsorbents, an agreement better than 10% was obtained. For treated resin-types a consistency within 30% but for impregnated alumina-types high discrepancy between respective values were obtained. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 0043-1354

DOI: 10.1016/j.watres.2009.09.031

Record 471 of 474

Author(s): Tammemae, O (Tammemaee, O.)

Title: BASICS FOR GEOTECHNICAL ENGINEERING EXPLORATIONS CONSIDERING NEEDED LEGAL CHANGES

Source: OIL SHALE, 25 (2): 189-196 Sp. Iss. SI 2008

Abstract: Nowadays legal system of Estonia does not cover essential aspects related to geotechnical engineering explorations for assessing environmental risks to be considered during planning processes and for providing designers with reliable geotechnical parameters for sustainable construction solutions. The absence of appropriate legal regulation does not support the reuse of mined areas and sustainable

use of mineral recourses. The article deals with analysis on planning and building sectors with concrete suggestions for changes in legal regulations. Additionally radon level survey and geotechnical inspection related issues have analysed in the frame of risk assessment. Both of the above issues are especially important to be considered in mined areas. The utilisation of previous research data and re-establishment of Geotechnical Fund will enable a much more economical use of the available resources and a better management of possible risks.

ISSN: 0208-189X

DOI: 10.3176/oil.2008.2S.10

Record 472 of 474

Author(s): Wittwer, D (Wittwer, D.); Abdullin, FS (Abdullin, F. Sh.); Aksenov, NV (Aksenov, N. V.); Albin, YV (Albin, Yu. V.); Bozhikov, GA (Bozhikov, G. A.); Dmitriev, SN (Dmitriev, S. N.); Dressler, R (Dressler, R.); Eichler, R (Eichler, R.); Gaggeler, HW (Gaeggeler, H. W.); Henderson, RA (Henderson, R. A.); Hubener, S (Huebener, S.); Kenneally, JM (Kenneally, J. M.); Lebedev, VY (Lebedev, V. Ya.); Lobanov, YV (Lobanov, Yu. V.); Moody, KJ (Moody, K. J.); Oganessian, YT (Oganessian, Yu. Ts.); Petrushkin, OV (Petrushkin, O. V.); Polyakov, AN (Polyakov, A. N.); Piguet, D (Piguet, D.); Rasmussen, P (Rasmussen, P.); Sagaidak, RN (Sagaidak, R. N.); Serov, A (Serov, A.); Shirokovsky, IV (Shirokovsky, I. V.); Shaughnessy, DA (Shaughnessy, D. A.); Shishkin, SV (Shishkin, S. V.); Sukhov, AM (Sukhov, A. M.); Stoyer, MA (Stoyer, M. A.); Stoyer, NJ (Stoyer, N. J.); Tereshatov, EE (Tereshatov, E. E.); Tsyganov, YS (Tsyganov, Yu. S.); Utyonkov, VK (Utyonkov, V. K.); Vostokin, GK (Vostokin, G. K.); Wegrzecki, M (Wegrzecki, M.); Wilk, PA (Wilk, P. A.)

Title: Gas phase chemical studies of superheavy elements using the Dubna gas-filled recoil separator - Stopping range determination

Source: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS, 268 (1): 28-35 JAN 1 2010

Abstract: Currently, gas phase chemistry experiments with heaviest elements are usually performed with the gas-jet technique with the disadvantage that all reaction products are collected in a gas-filled thermalisation chamber adjacent to the target. The incorporation of a physical preseparation device between target and collection chamber opens up the perspective to perform new chemical studies. But this approach requires detailed knowledge of the stopping force (STF) of the heaviest elements in various materials. Measurements of the energy loss of mercury (Hg), radon (Rn), and nobelium (No) in Mylar and argon (Ar) were performed at low kinetic energies of around (40-270) keV per nucleon. The experimentally obtained values were compared with STF calculations of the commonly used program for calculating stopping and ranges of ions in matter (SRIM). Using the obtained data points an extrapolation of the STF up to element 114, eka-lead, in the same stopping media was carried out. These estimations were applied to design and to perform a first chemical experiment with a superheavy element behind a physical preseparator using the nuclear fusion reaction Pu-244(Ca-48; 3n)(289)114. One decay chain assigned to an atom of (285)112, the alpha-decay product of (289)114, was observed. (c) 2009 Elsevier B.V. All rights reserved.

ISSN: 0168-583X

DOI: 10.1016/j.nimb.2009.09.062

Record 473 of 474

Author(s): Freund, FT (Freund, Friedemann T.); Kulahci, IG (Kulahci, Ipek G.); Cyr, G (Cyr, Gary); Ling, J (Ling, Julia); Winnick, M (Winnick, Matthew); Tregloan-Reed, J (Tregloan-Reed, Jeremy); Freund, MM (Freund, Minoru M.)

Title: Air ionization at rock surfaces and pre-earthquake signals

Source: JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS, 71 (17-18): 1824-1834 DEC 2009

Abstract: Pre-earthquake signals have been widely reported, including perturbations in the ionosphere. These precursory signals, though highly diverse, may be caused by just one underlying physical process: activation of highly mobile electronic charge carriers in rocks that are subjected to ever increasing levels of stress. The charge carriers are defect electrons associated with O- in a matrix of O2-. Known as positive holes or pholes h(center dot), they flow out of the stressed rock into the unstressed rock volume, traveling meters in the laboratory, probably kilometers in the field. At the rock-air interface they cause: (i) positive surface potential, (ii) field-ionization of air molecules, (iii) corona discharges. The rate of formation of airborne ions can exceed 10(9) cm(-2) s(-1). Massive air ionization prior to major earthquakes increases the electrical conductivity in the air column and may cause ionospheric perturbations,

earthquake lights, and unusual animal behavior as well as infrared emission. (C) 2009 Elsevier Ltd. All rights reserved.

ISSN: 1364-6826

DOI: 10.1016/j.jastp.2009.07.013

Record 474 of 474

Author(s): van der Laan, S (van der Laan, S.); Neubert, REM (Neubert, R. E. M.); Meijer, HAJ (Meijer, H. A. J.)

Title: Methane and nitrous oxide emissions in The Netherlands: ambient measurements support the national inventories

Source: ATMOSPHERIC CHEMISTRY AND PHYSICS, 9 (24): 9369-9379 2009

Abstract: We present net emission estimates of CH4 and N2O of The Netherlands based on measurements conducted during the period of May 2006 to April 2009 at station Lutjewad, The Netherlands (6 degrees 21' E, 53 degrees 24' N, 1 m a.s.l.). (222)Radon mixing ratios were applied as an indicator for vertical mixing and long-range air mass transport and used to calculate the net surface fluxes from atmospheric mixing ratios of CH4 and N2O. Our study shows that our measurement site Lutjewad is well-suited to measure emissions from The Netherlands and validation of the national inventories using the (222)Radon flux method. Since this study is purely observation-based it is independent from inventories or atmospheric models. Our results are compared to the national inventories as reported to the UNFCCC. We found net emissions of: (15.2 +/- 5.3) t km(-2) a(-1) for CH4 and (0.9 +/- 0.3) t km(-2) a(-1) for N2O. These values are lower than the inventory-based emissions (2006-2008 averages) of (18.3 +/- 3.3) t km(-2) a(-1) for CH4, and (1.3 +/- 0.6) t km(-2) a(-1) for N2O, but the differences are insignificant.

ISSN: 1680-7316

record 401 of 474 author(s): arnold, d (arnold, d.)

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