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Journal of Environmental Radioactivity

Kelly C McHugh, Elisabeth Widom, Henry B Spitz, Gregory C Wiles, Sam E Glover
Black walnut (Juglans nigra), slippery elm (Ulmus rubra), and white ash (Fraxinus americana) trees were evaluated as potential archives of past uranium (U) contamination. Like other metals, U mobility in annual growth rings of trees is dependent on the tree species. Uranium concentrations and isotopic compositions (masses 234, 235, 236, and 238) were analyzed by thermal ionization mass spectrometry to test the efficacy of using tree rings to retroactively monitor U pollution from the FFMPC, a U purification facility operating from 1951 to 1989...
November 14, 2017: Journal of Environmental Radioactivity
Weiqing Wang, E Gert Dudel
The influences of N species and transpiration on the Fe plaque (IP) formation and related aquatic U rhizofiltration had not revealed yet, especially when these factors were co-existed. It was evaluated in a mesocosm experiment in the condition of respective ammonium (NH4(+))/nitrate (NO3(-)) cultivation of Phragmites australis Trin ex Steud. coupled with different transpiration rates (TRs). The results suggested that the enhanced transpiration of P. australis improved the aquatic U rhizofiltration in both NO3(-) and NH4(+) rich milieus...
November 14, 2017: Journal of Environmental Radioactivity
Ivana Tucaković, Delko Barišić, Željko Grahek, Ante Kasap, Ivan Širić
The aim of this study was to select species with higher potential to accumulate (137)Cs among the available mushroom species, by determining the activity concentrations of (137)Cs in mushrooms collected along north and north-western part of Croatia. A total of 55 samples of 14 different species were analyzed and the potential of mycorrhizal and saprotrophic species to accumulate (137)Cs was compared. A wide range of the dry weight activity concentrations of (137)Cs was detected, ranging from 0.95 to 1210 Bq/kg (154 Bq/kg mean value; 52...
November 14, 2017: Journal of Environmental Radioactivity
Frédérique Eyrolle, Loïc Ducros, Séverine Le Dizès, Karine Beaugelin-Seiller, Sabine Charmasson, Patrick Boyer, Catherine Cossonnet
Various studies indicated more or less recently that organically bound tritium (OBT) formed from gaseous or liquid tritium releases into the environment potentially accumulates in organisms contradicting hypotheses associated to methods used to assess the biological impact of tritium on humans (ASN, 2010). Increasing research works were then performed during the last decade in order to gain knowledge on this radionuclide expected to be increasingly released by nuclear installations in the near future within the environment...
November 14, 2017: Journal of Environmental Radioactivity
William J Walters, Villy Christensen
Ecotracer is a tool in the Ecopath with Ecosim (EwE) software package used to simulate and analyze the transport of contaminants such as methylmercury or radiocesium through aquatic food webs. Ecotracer solves the contaminant dynamic equations simultaneously with the biomass dynamic equations in Ecosim/Ecospace. In this paper, we give a detailed description of the Ecotracer module and analyze the performance on two problems of differing complexity. Ecotracer was modified from previous versions to more accurately model contaminant excretion, and new numerical integration algorithms were implemented to increase accuracy and robustness...
November 13, 2017: Journal of Environmental Radioactivity
P Zoriy, M Schläger, K Murtazaev, J Pillath, M Zoriy, B Heuel-Fabianek
The water contamination near ecologically problematic objects was investigated between 2009 and 2014 in North-West Tajikistan as a part of a joint project between Forschungszentrum Jülich and Khujand State University. The main part of this work was the determination of uranium in water samples collected near the Degmay tailings dump, the Taboshar pit lake and the Syr Darya river. More than 130 water samples were collected and analyzed to monitor the uranium concentration near the investigated areas. Two different mass spectrometers and an ion chromatograph were used for element concentration measurements...
November 11, 2017: Journal of Environmental Radioactivity
Dusan Mrdja, Kristina Bikit, Sofija Forkapic, Istvan Bikit, Jaroslav Slivka, Jan Hansman
Performing in-situ measurements of gamma radiation originating from soil requires adequate detection efficiency curves, which can be obtained by Monte-Carlo simulations. In simulations, soil density of 1.046 g/cm(3) was used, with the following elemental composition of soil in which gamma radiation was generated: O - 47%, Si -35%, Al - 8%, Fe - 3.9%, C - 2.1%, Ca - 1.4%, K - 1.3%, N - 0.6%, Mg - 0.6%, N - 0.1%. Soil matrix was represented by cylindrical volume of 1.5 m diameter and 0.5m thickness, while germanium detector was placed at 1 m height above the soil...
November 10, 2017: Journal of Environmental Radioactivity
Sung Ho Hwang, Jae Bum Park, Wha Me Park
In this study, the environmental factors that affect radon (Rn) and nitrogen dioxide (NO2) levels in subway-station underground platforms are evaluated, and the outdoor NO2 levels are compared with those obtained for the underground platforms. The Rn and NO2 levels from May 2013 to September 2015 are determined for lines 1-4 of the Seoul Metro, via calculation of the arithmetic means of the Rn and NO2 levels with their standard deviations (SDs). The underground Rn levels in 2013 are found to be significantly higher than those recorded in 2015 for the Seoul Metro...
November 10, 2017: Journal of Environmental Radioactivity
Tae Ho Ryu, Jin Kyu Kim, Jeong-Il Kim, Jin-Hong Kim
Plants are used as representative reference biota for the biological assessment of environmental risks such as ionizing radiation due to their immobility. This study proposed a faster, more economical, and more effective method than conventional cytogenetic methods for the biological dosimetry of ionizing radiation in plants (phytodosimetry). We compared various dose-response curves for the radiation-induced DNA damage response (DDR) in Arabidopsis thaliana after relatively "low-dose" gamma irradiation (3, 6, 12, 24, and 48 Gy) below tens of Gy using comet (or single-cell gel electrophoresis), gamma-H2AX, and transcriptomic assays of seven DDR genes (AGO2, BRCA1, GRG, PARP1, RAD17, RAD51, and RPA1E) using quantitative real time PCR...
November 9, 2017: Journal of Environmental Radioactivity
Anne Felsberg, J Ole Ross, Clemens Schlosser, Gerald Kirchner
Due to its half-life, chemical inertness and low solubility in water, radioactive (85)Kr is a valuable tracer for testing the performance of atmospheric dispersion models in simulating long-range transport of pollutants. This paper evaluates the capability of simulating the dispersion of radiokrypton emitted by a nuclear fuel reprocessing plant in north-west France. Three time periods during which elevated activity concentrations of (85)Kr in ground level air were detected in south-west Germany are chosen. Simulations have been performed using the HYSPLIT code and the European Centre for Median-Range Weather Forecasts (ECMWF) data base...
November 9, 2017: Journal of Environmental Radioactivity
Fernando P Carvalho
The first measurements made of artificial radionuclides released into the marine environment did reveal that radionuclides are concentrated by marine biological species. The need to report radionuclide accumulation in biota in different conditions and geographical areas prompted the use of concentration factors as a convenient way to describe the accumulation of radionuclides in biota relative to radionuclide concentrations in seawater. Later, concentration factors became a tool in modelling radionuclide distribution and transfer in aquatic environments and to predicting radioactivity in organisms...
November 8, 2017: Journal of Environmental Radioactivity
N Yu Mirzoyeva, S I Arkhipova, N V Kravchenko
At the first time for the period after the Chernobyl NPP accident the nature of the redistribution of the (90)Sr concentrations in components of the ecosystems of the salt lakes of the Crimea were identified and described. Concentration of (90)Sr in water of the salt lakes depends on the sources of the inflow this radionuclide into aquatic ecosystems and salinity level of lakes water. Until April 2014 the flow of the Dnieper river water through the Northern-Crimean canal was more important factor of contamination of salt lakes of the Crimea by (90)Sr, than atmospheric fallout of this radionuclide after the Chernobyl NPP accident...
November 4, 2017: Journal of Environmental Radioactivity
N N Tereshchenko, S B Gulin, V Yu Proskurnin
Distribution of (239,240)Pu in abiotic components (water and bottom sediment) of the Black Sea ecosystems was studied during the post-Chernobyl period at different offshore and near-shore locations. The trends of these radionuclides accumulation by sediments were analyzed. The spatial-temporal changes in the (239,240)Pu distribution as well as effective half-life for these radionuclides in the Black Sea surface water in deep-sea area are presented. The estimations of the average annual removal fluxes of the (239,240)Pu into the bottom sediments were obtained...
November 3, 2017: Journal of Environmental Radioactivity
Kexin Zhang, Shaoming Pan, Zhiyong Liu, Guosheng Li, Yihong Xu, Yongpei Hao
Activity concentration of plutonium (Pu) and its isotopic compositions are extensively used for measuring transport processes of Pu and identifying its source. We investigated the spatial distribution characteristics of (239+240)Pu activity concentrations and (240)Pu/(239)Pu atom ratio in several sediment cores collected from the Liao River coastal zone. Additionally, we calculated the (239+240)Pu inventories and based on the (240)Pu/(239)Pu atom ratio to trace Pu source. The activity concentrations of (239+240)Pu in surface sediments of the Liao River estuary ranged between 0...
November 3, 2017: Journal of Environmental Radioactivity
Jácint Jónás, János Somlai, Anita Csordás, Edit Tóth-Bodrogi, Tibor Kovács
In petroleum engineering, the produced drilling mud sometimes contains elevated amounts of natural radioactivity. In this study, a remediated Hungarian drilling mud depository was investigated from a radiological perspective. The depository was monitored before and after a clay layer was applied as covering. In this study, the ambient dose equivalent rate H*(10) of the depository has been measured by a Scintillator Probe (6150AD-b Dose Rate Meter). Outdoor radon concentration, radon concentration in soil gas, and in situ field radon exhalation measurements were carried out using a pulse-type ionization chamber (AlphaGUARD radon monitor)...
November 2, 2017: Journal of Environmental Radioactivity
M I Kaniu, H K Angeyo, I G Darby, L M Muia
This paper presents the radiometric survey results of the Mrima-Kiruku high background radiation (HBR) anomaly complex of south coastal Kenya. Utilizing a portable γ-ray spectrometer consisting of a 2.0 l NaI(Tl) backpack detector integrated with GPS to perform the relevant in-situ radiometric measurements, a novel geospatial gating method was devised to represent the measurements. The goal of this study was to assess radiation exposure and associated natural radioactivity levels in the complex and to compare the results obtained with those from previous preliminary related studies...
November 2, 2017: Journal of Environmental Radioactivity
Alan J Cresswell, David C W Sanderson, Katsuhiko Yamaguchi
A Monte Carlo simulation was used to develop a model of the response of a portable gamma spectrometry system in forest environments. This model was used to evaluate any corrections needed to measurements of (137)Cs activity per unit area calibrated assuming an open field geometry. These were shown to be less than 20% for most forest environments. The model was also used to assess the impact of activity in the canopy on ground level measurements. For similar activity per unit area in the lower parts of the canopy as on the ground, 10-25% of the ground based measurement would be due to activity in the canopy, depending on the depth profile in the soil...
November 2, 2017: Journal of Environmental Radioactivity
Mitra Kiani Nasab, Laleh Rafat Motavalli, Hashem Miri Hakimabad
In this paper, the dose assessment for the iodine inhalation exposure in 19 aerosol sizes and three gas/vapor forms at three levels of thyroid uptake, was performed. Two different modes of work (light vs. heavy) and breathing (nose vs. mouth) for aerosol inhalation were investigated. In order to calculate the cumulated activities per unit of inhaled activity, a combined model which included the latest models of both human respiratory and alimentary tract was developed. The S values for (131)I were computed based on the ICRP adult male and female reference voxel phantoms by the Monte Carlo method...
November 1, 2017: Journal of Environmental Radioactivity
N Baglan, C Cossonnet, E Roche, S B Kim, I Croudace, P Warwick
Organically bound tritium (OBT) has become of increasing interest within the last decade, with a focus on its behaviour and also its analysis, which are both important to assess tritium distribution in the environment and dose consequences. After the first OBT International Workshop which was held in France in May 2012, an international working group was created. The expected benefits are the following: remove or reduce uncertainty in OBT analysis results, provide better OBT model validation data and better public dose results, increase the number of potential measuring OBT laboratories, validate all of the stages of the procedures based on a larger population and more statistically significant results, and investigate the feasibility of CRM's and RM's production...
October 31, 2017: Journal of Environmental Radioactivity
Ate Visser, Melissa Thaw, Brad Esser
Understanding the behavior of tritium, a radioactive isotope of hydrogen, in the environment is important to evaluate the exposure risk of anthropogenic releases, and for its application as a tracer in hydrology and oceanography. To understand and predict the variability of tritium in precipitation, HYSPLIT air mass trajectories were analyzed for 16 aggregate precipitation samples collected over a 2 year period at irregular intervals at a research site located at 2000 m elevation in the southern Sierra Nevada (California, USA)...
October 30, 2017: Journal of Environmental Radioactivity
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