Table Of ContentRecord 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
Source: JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY, 283 (2): 493-495 FEB 2010
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
Source: JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY, 283 (2): 507-512 FEB 2010
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
Source: JOURNAL OF ENVIRONMENTAL RADIOACTIVITY, 101 (2): 113-121 FEB 2010
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
Source: JOURNAL OF ENVIRONMENTAL RADIOACTIVITY, 101 (2): 153-158 FEB 2010
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
Description:Title: Analysis of radon origin by backward atmospheric transport modelling ..
agreement between the measurement of uranium and thorium with both methods
