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Journal of Environmental Radioactivity

Mathew P Johansen, Emily Prentice, Tom Cresswell, Nick Howell
The adsorption of radiocesium and radiostrontium onto a range of natural materials has been well quantified, but not for the new media of environmental plastics, which may have enhanced adsorption due to surface-weathering and development of biofilms. Microplastic samples were deployed in freshwater, estuarine and marine conditions, then characterised using infrared spectroscopy to document changes to the plastic surface (vs interior). Synchrotron elemental mapping data revealed surfaces that were well-covered by accumulation of reactive water solutes and sulphur, but, in contrast, had highly discrete coverage of elements such as Fe and Ti, indicating adhered mineral/clay-associated agglomerates that may increase overall adsorption capacity...
May 19, 2018: Journal of Environmental Radioactivity
Franziska D H Wilke, Georg Schettler, Andrea Vieth-Hillebrand, Michael Kühn, Heike Rothe
The production of gas from unconventional resources became an important position in the world energy economics. In 2012, the European Commission's Joint Research Centre estimate 16 trillion cubic meters (Tcm) of technically recoverable shale gas in Europe. Taking into account that the exploitation of unconventional gas can be accompanied by serious health risks due to the release of toxic chemical components and natural occurring radionuclides into the return flow water and their near-surface accumulation in secondary precipitates, we investigated the release of U, Th and Ra from black shales by interaction with drilling fluids containing additives that are commonly employed for shale gas exploitation...
May 18, 2018: Journal of Environmental Radioactivity
Masaki Andoh, Hideaki Yamamoto, Takashi Kanno, Kimiaki Saito
Ambient dose equivalent rates in various environments related to human lives were measured by walk surveys using the KURAMA-II systems from 2013 to 2016 within an 80-km radius of the Fukushima Dai-ichi Nuclear Power Plant. The dose rate of the locations where the walk survey was performed decreased to about 38% of its initial value in the 42 months from June 2013 to the December 2016, which was beyond that attributable to the physical decay of radiocaesium. The ecological half-life of the slow decreasing component was evaluated to be 4...
May 17, 2018: Journal of Environmental Radioactivity
Octavian G Duliu, Carmen Varlam, Muataz Dheyaa Shnawaw
To get more information on the origin of tritium and to evidence any possible presence of anthropogenic sources, between January 1999 and December 2016, the precipitation level and tritium concentration were monthly recorded and investigated by the Cryogenic Institute of Ramnicu Valcea, Romania. Compared with similar data covering a radius of about 1200 km westward, the measurements gave similar results concerning the time evolution of tritium content and precipitation level for the entire time interval excepting the period between 2009 and 2011 when the tritium concentrations showed a slight increase, most probable due to the activity of neighboring experimental pilot plant for tritium and deuterium separation...
May 16, 2018: Journal of Environmental Radioactivity
K Rosén, L Lenoir, K Stark, M Vinichuk, S Sundell-Bergman
In forest ecosystems soil organisms are important for immobilization, translocation and recycling of radionuclides. Still, there is a lack of studies on the role of insects such as ants in the turnover of radionuclides and how radioactivity affects an ant community. In this study seven anthills were sampled in an area that was heavily contaminated after the fallout from the Chernobyl accident. Samples of ant and anthill materials were taken from different depths of the anthills as well as from the surrounding soil and the activity concentrations of 137 Cs were determined...
May 15, 2018: Journal of Environmental Radioactivity
H P Emerson, F Zengotita, M Richmann, Y Katsenovich, D T Reed, T M Dittrich
The results presented in this paper highlight the complexity of adsorption and incorporation processes of Nd with dolomite and significantly improve upon previous work investigating trivalent actinide and lanthanide interactions with dolomite. Both batch and mini column experiments were conducted at variable ionic strength. These data highlight the strong chemisorption of Nd to the dolomite surface (equilibrium Kd 's > 3000 mL/g) and suggest that equilibrium adsorption processes may not be affected by ionic strength based on similar results at 0...
May 15, 2018: Journal of Environmental Radioactivity
Hiroki Mukai, Kenji Tamura, Ryosuke Kikuchi, Yoshio Takahashi, Tsuyoshi Yaita, Toshihiro Kogure
For the better understanding of radioactive contamination in Fukushima Prefecture at present and in future, Cs desorption experiments have been conducted mainly using weathered biotite (WB) collected from Fukushima Prefecture and considering the actual contamination level (∼10-10  wt%) of radiocesium in Fukushima Prefecture. In the experiments, 137 Cs sorbed to WB by immersing in 137 Cs solution for one day was mostly desorbed by solutions of 1 M NaNO3 , 1 M LiNO3 , 10-1  M HCl, and 10-1  M HNO3 , although it was barely desorbed by 1 M KNO3 , 1 M CsNO3 , 1 M NH4 NO3 , and natural seawater...
May 15, 2018: Journal of Environmental Radioactivity
Kui Zhang, Tao Chen
Removal of IO3 - from environmental samples with low-cost methods and materials is very useful approach for especially large-scale applications. Corn stalk is highly abundant agriculture residual, which is employed as useful biosorbent in many studies. In the present work, dried powder of corn stalk is applied for the removal of IO3 - under various conditions. The results indicate that the Kd is 49.73 ml g-1 under general conditions (m/V = 8 g L-1 , t = 5 day, equilibrium pH = 7 ± 0...
May 11, 2018: Journal of Environmental Radioactivity
M Sabzian, M N Nasrabadi, M Haji-Hosseini
The dynamic adsorption of xenon on molecular sieve packed columns was investigated. The modified Wheeler-Jonas equation was used to describe adsorption parameters such as adsorption capacity and adsorption rate coefficient. Different experimental conditions were accomplished to study their effects and to touch appropriate adsorbing circumstances. Respectable consistency was reached between experimental and modeled values. A purification and analysis setup was developed for radioactive xenon gas determination...
May 10, 2018: Journal of Environmental Radioactivity
Guido Cervone, Carolynne Hultquist
A methodology is presented to calibrate contributed Safecast dose rate measurements acquired between 2011 and 2016 in the Fukushima prefecture of Japan. The Safecast data are calibrated using observations acquired by the U.S. Department of Energy at the time of the 2011 Fukushima Daiichi power plant nuclear accident. The methodology performs a series of interpolations between the U.S. government and contributed datasets at specific temporal windows and at corresponding spatial locations. The coefficients found for all the different temporal windows are aggregated and interpolated using quadratic regressions to generate a time dependent calibration function...
May 8, 2018: Journal of Environmental Radioactivity
Pascale Henner, Félix Brédoire, Antoine Tailliez, Frédéric Coppin, Sylvie Pierrisnard, Virginie Camilleri, Catherine Keller
Mechanisms of uranium (U) transfer from soil to plants remain poorly understood. The kinetics of supply of U to the soil solution from solid phases could be a key point to understand its phytoavailability and implications for environmental risk assessment. Root activity, particularly the continuous release of organic acids in the rhizosphere, could have an effect on this supply. We tested the impact of citrate exudation by roots of Lupinus albus, either P-sufficient (P+) or P-deficient (P-), on the phytoavailability of U from a naturally contaminated soil (total content of 413 mg U kg-1 ) using a rhizotest design...
May 8, 2018: Journal of Environmental Radioactivity
Chuanlei Liu, Weihua Zhang, Kurt Ungar, Ed Korpach, Brian White, Mike Benotto, Eric Pellerin
This work explores the application of Health Canada's Fixed Point Surveillance (FPS) network for cosmic ray monitoring and dose estimation purposes. This network is comprised of RS250 3 inch by 3 inch Sodium Iodide (NaI) spectroscopic dosimeters distributed throughout Canada. The RS250's high channel count rate responds to the electromagnetic and muonic components of cosmic ray shower. These count rates are used to infer cosmic ray doses throughout FPS locations. The derived dose was found to have an accuracy within 6...
May 7, 2018: Journal of Environmental Radioactivity
Narimane Dorey, Sophie Martin, François Oberhänsli, Jean-Louis Teyssié, Ross Jeffree, Thomas Lacoue-Labarthe
The marine organisms which inhabit the coastline are exposed to a number of anthropogenic pressures that may interact. For instance, the accumulation of toxic metals present in coastal waters is expected to be modified by ocean acidification through e.g. changes in physiological performance and/or elements availability. Changes in bioaccumulation due to lowering pH are likely to be differently affected depending on the nature (essential vs. non-essential) and speciation of each element. The Mediterranean is of high concern for possible cumulative effects due to strong human influences on the coastline...
May 5, 2018: Journal of Environmental Radioactivity
Willy Ciecior, Klaus-Jürgen Röhlig, Gerald Kirchner
In the present paper, deterministic as well as first- and second-order probabilistic biosphere modeling approaches are compared. Furthermore, the sensitivity of the influence of the probability distribution function shape (empirical distribution functions and fitted lognormal probability functions) representing the aleatory uncertainty (also called variability) of a radioecological model parameter as well as the role of interacting parameters are studied. Differences in the shape of the output distributions for the biosphere dose conversion factor from first-order Monte Carlo uncertainty analysis using empirical and fitted lognormal distribution functions for input parameters suggest that a lognormal approximation is possibly not always an adequate representation of the aleatory uncertainty of a radioecological parameter...
May 4, 2018: Journal of Environmental Radioactivity
Simon Pouil, François Oberhänsli, Peter W Swarzenski, Paco Bustamante, Marc Metian
In order to better understand the influence of changing salinity conditions on the trophic transfer of 137 Cs in marine fish that live in dynamic coastal environments, its depuration kinetics was investigated in controlled aquaria. The juvenile turbot Scophthalmus maximus was acclimated to three distinct salinity conditions (10, 25 and 38) and then single-fed with compounded pellets that were radiolabelled with 137 Cs. At the end of a 21-d depuration period, assimilation efficiencies (i.e. AEs = proportion of 137 Cs ingested that is actually assimilated by turbots) were determined from observational data acquired over the three weeks...
May 4, 2018: Journal of Environmental Radioactivity
Ravi Gudavalli, Yelena Katsenovich, Dawn Wellman
Uranium is a key contaminant of concern in the groundwater at U.S. Department of Energy (DOE) facilities within the United States and is a potential source of groundwater contamination and a risk to human health and the environment through discharges to surface water. Dissolved inorganic carbon (bicarbonate/carbonate) has a high affinity for complexing with uranium that is present as sorbed or unique uranium-bearing mineral phases within the sedimentary matrix. This process can result in the formation of soluble uranyl carbonate aqueous species, which are mobile under circumneutral pH conditions...
May 2, 2018: Journal of Environmental Radioactivity
Mutsuo Inoue, Toshiki Morokado, Ken Fujimoto, Shizuho Miki, Hisaki Kofuji, Yutaka Isoda, Seiya Nagao
We examined the vertical 134 Cs and 137 Cs concentration profiles in the southwestern Okhotsk Sea in 2011, 2013, and 2017. In June 2011, atmospheric deposition-derived 134 Cs from the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) was detected at depths of 0-200 m (0.06-0.6 mBq/L). In July 2013, 134 Cs detected at depths of 100-200 m (∼0.05 mBq/L) was ascribed to the transport of low-level 134 Cs-contaminated water and/or the convection of radioactive depositions (<0.03 mBq/L at depths of 0-50 m)...
April 30, 2018: Journal of Environmental Radioactivity
Simon Pouil, Jean-Louis Teyssié, Scott W Fowler, Marc Metian, Michel Warnau
The trophic transfer of radiocesium (134 Cs) was investigated in two tropical fish, the silver moony Monodactylus argenteus and the spotted scat Scatophagus argus. Juveniles of both species were exposed to dietary 134 Cs using the pulse-chase feeding methodology. The food was brine shrimp (Artemia salina) previously exposed to the dissolved radiotracer. Depuration kinetics of 134 Cs were followed for 45 d. Results showed that Cs was similarly efficiently assimilated by both species (AE > 50%). The estimated trophic transfer factors in the two species ranked from 1 to 2, suggesting that 134 Cs could be biomagnified in both omnivorous species...
April 30, 2018: Journal of Environmental Radioactivity
Mara M Watson, Ayman F Seliman, Valery N Bliznyuk, Timothy A DeVol
Water can become contaminated as a result of a leak from a nuclear facility, such as a waste facility, or from clandestine nuclear activity. Low-level on-line radiation monitoring is needed to detect these events in real time. A Bayesian control chart method, Shiryaev-Roberts (SR) procedure, was compared with classical methods, 3-σ and cumulative sum (CUSUM), for quantifying an accumulating signal from an extractive scintillating resin flow-cell detection system. Solutions containing 0.10-5.0 Bq/L of 99 Tc, as T99cO4 - were pumped through a flow cell packed with extractive scintillating resin used in conjunction with a Beta-RAM Model 5 HPLC detector...
April 30, 2018: Journal of Environmental Radioactivity
Marcilei A Guazzelli da Silveira, Bruno Ribeiro Pereira, Nilberto H Medina, Marcia A Rizzutto
This study reports the results obtained in the analysis of waste material samples generated by the industries of phosphate fertilizers, in particular, the use of specific filters in a portable X-ray fluorescence system, a simple equipment allowing the characterization, identification and quantification of low concentrations of Th and U (ppm). The industrial byproduct is classified as a Technologically-Enhanced, Naturally-Occurring Radioactive Material - TENORM, and therefore requires monitoring for its radio-toxic activity due to the presence of radioactive thorium and uranium families...
April 28, 2018: Journal of Environmental Radioactivity
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