Journal of environmental radioactivity最新文献

{"title":"Investigation of dense plumes in porous media using CsNO3 solute and phenolphthalein tracer","authors":"Amita Singh,&nbsp;Chunendra K. Sahu","doi":"10.1016/j.jenvrad.2024.107558","DOIUrl":"10.1016/j.jenvrad.2024.107558","url":null,"abstract":"<div><div>We present results from the laboratory experiments performed to study the behaviour of dense plumes in porous media using Caesium Nitrate (CsNO₃) as the solute. Specifically, we consider the case of fixed volume release of a dense fluid into a saturated porous medium of lighter density. Our experiments consider the injection volume and concentration of CsNO₃ and the porous medium permeability as experimental variables. Our measurements show that the plume length and volume increase with time approximately as <span><math><msup><mrow><mi>t</mi></mrow><mrow><mn>0</mn><mo>.</mo><mn>5</mn></mrow></msup></math></span>. The mean concentration of the plume decreases with time as plume monotonically dilutes due to continuous mixing with the surrounding. From our measurements and with the help of dimensionless scaling, we present empirical models for the length, volume and mean concentration of the plume. Our results may be used to gain preliminary insights into the spatio-temporal evolution of plumes formed in the subsurface environment.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107558"},"PeriodicalIF":1.9,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142603669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical retardation of actinide-bearing colloid migration from an underground repository: Theory and experiment","authors":"Victor Malkovsky,&nbsp;Andrey Zharikov,&nbsp;Sergey Yudintsev","doi":"10.1016/j.jenvrad.2024.107559","DOIUrl":"10.1016/j.jenvrad.2024.107559","url":null,"abstract":"<div><div>A necessary condition for the sustainable development of nuclear power is the safe disposal of vitrified high-level radioactive waste from the processing of spent nuclear fuel in underground repositories. Their safety depends on the rate of radionuclide transport by groundwater from the repository to the biosphere. A significant fraction of the radionuclides is carried by groundwater in colloidal form. The radionuclide-bearing colloid (radiocolloid) is the most mobile and therefore the most ecologically hazardous form of radionuclide transport. The radiocolloid can be retained mechanically in the rock if the colloid particle size is larger than diameter of rock pore channels. Transport of radionuclide-bearing colloid by groundwater is considered. (1) A technique for determining the size distribution of pore channels in the rock is developed. It is based on measurements of the gas permeability of rock samples at different pressures. (2) The technique is applied to rock samples from the Nizhnekanskiy Massif (Russia), which has been selected for the development of a high-level radioactive waste repository. (3) Simulated radionuclide-bearing colloids were obtained by water leaching of aged aluminum phosphate glass with radionuclide simulants. The glass composition is similar to that used for vitrification of liquid HLW at the Russian radiochemical plant. (4) The size distribution of the colloid was determined by filtering the leachates through membranes of different pore sizes. (5) Mechanical retention of the colloid by the rock is estimated theoretically. The estimation is based on size distributions of colloid particles and diameters of pore channels in the rock. It is shown that 99% of the colloidal form of the actinide simulants (Ce, Nd, U) can be mechanically retained in the rock of the Nizhnekanskiy Massif.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107559"},"PeriodicalIF":1.9,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142578155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of temperature on the radon release characteristics of red clay","authors":"Chao Gu ,&nbsp;Qiang Sun ,&nbsp;Lei Zhang ,&nbsp;Liwei Zhang ,&nbsp;Duoxing Yang ,&nbsp;Boxing Yang ,&nbsp;Zhenlong Ge","doi":"10.1016/j.jenvrad.2024.107565","DOIUrl":"10.1016/j.jenvrad.2024.107565","url":null,"abstract":"<div><div>Bricks and tiles crafted from fired red clay are extensively utilized in everyday construction activities. However, red clay inherently contains radon gas, a radioactive substance that could potentially endanger human health. Hence, investigating the radon emission patterns of red clay post high-temperature treatment holds significant importance. This study examines the pore structure of red clay following high-temperature treatment through nitrogen adsorption and analyzes the radon release patterns. Findings reveal that the radon release rate from red clay initially rises, then declines with increasing temperature, peaking at 200 °C, registering at 0.0127 Bq/(m² s). The pore structure significantly influences radon exhalation, with connectivity and micropore volume demonstrating linear correlations with radon exhalation rate, with correlation coefficients of 0.96 and 0.78, respectively. This research offers valuable insights into radon radiation in structures made of red clay.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107565"},"PeriodicalIF":1.9,"publicationDate":"2024-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142564021","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geant4 Monte Carlo simulation of human exposure to indoor 222Rn from building materials","authors":"Felix Haman ,&nbsp;Cebastien Joël Guembou Shouop ,&nbsp;Dorine Flore Tiomene ,&nbsp;Daniel Bongue ,&nbsp;Patricia-Laurelle Degbe ,&nbsp;Eric Jilbert Nguelem Mekontso ,&nbsp;Maurice Ndontchueng Moyo ,&nbsp;Moïse Godfroy Kwato Njock","doi":"10.1016/j.jenvrad.2024.107562","DOIUrl":"10.1016/j.jenvrad.2024.107562","url":null,"abstract":"<div><div>The present study aimed to develop a Monte Carlo model to estimate the annual effective dose due to radon exposure sourced by radon gas in the walls and floor of a standard model room. With the purpose of developing a tool for radon level assessment in dwellings and workplaces, Geant4 toolkit was used to simulate the energy deposited by gamma rays emitted by radioactive radon progeny in a water phantom positioned at three different locations within the model room. The energy deposition was then used to estimate the annual effective dose through a deterministic approach. The simulation outcomes showed good agreement with experimental data, with the ratio between the simulated and the experimental data displaying the overestimation by a factor of approximately 1.09. Both simulation and experimental data fell within the same range, with a relative deviation of 7.7%. Additionally, the influence of various parameters, such as receptor position in the room, wall, and floor thicknesses, wall cover, and building material bulk density, on the annual effective dose due to radon inhalation in the room was evaluated. Geant4 Monte Carlo toolkit proved to be a reliable tool for radon modeling in real exposure situations.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107562"},"PeriodicalIF":1.9,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142545804","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Long-range transport model analysis on seasonal and spatial variations of 210Pb deposition across Asia","authors":"Yu Cai ,&nbsp;Hiromi Yamazawa ,&nbsp;Takeshi Iimoto","doi":"10.1016/j.jenvrad.2024.107563","DOIUrl":"10.1016/j.jenvrad.2024.107563","url":null,"abstract":"<div><div>This study analyzed the transport and deposition of ²¹⁰Pb across Asia, particularly focused on Japan, from 2012 to 2015, used an atmospheric transport model that combines WRF and HIRAT. Results indicated that modeled deposition fluxes aligned well with observation data. The average deposition flux in Asia is 17.2 Bq m⁻² month⁻¹, showed significant seasonal variation. Along the Sea of Japan, the four-year average was 27.0 Bq m⁻² month⁻¹, with winter peaks in Hokkaido and Tohoku-Hokuriku and summer peaks in Kyushu. The calculation results showed distinct seasonal transport routes. During summer in Kyushu, southerly and westerly winds from southern China (e.g., Guangdong and Fujian) transported ²¹⁰Pb-enriched air masses. Stationary fronts carried these air masses from the southwestern Chinese basin, leading to intensified deposition. In winter, along the northern Japan Sea coast, high ²¹⁰Pb deposition events were closely associated with the East Asian winter monsoon, characterized by East Asian troughs and Siberian highs. Strong northwesterly winds from Siberia transported ²¹⁰Pb-enriched air masses to the Hokkaido and Tohoku-Hokuriku coastal regions, resulting in significant deposition. Approximately 47% of the high winter ²¹⁰Pb deposition events originated from the Kazakhstan-Xinjiang border, while the remaining 53% came from eastern Siberia.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107563"},"PeriodicalIF":1.9,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142545805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigation of naturally occurring radionuclides in selected medicinal plants and associated soils, and calculation of soil-to-plant transfer factors","authors":"Madan Khanal ,&nbsp;Arjun Acharya ,&nbsp;Rajesh Maharjan ,&nbsp;Devendra Raj Upadhyay ,&nbsp;Saddam Husain Dhobi ,&nbsp;Buddha Ram Shah ,&nbsp;Rameshwar Adhikari ,&nbsp;Deependra Das Mulmi ,&nbsp;Tika Ram Lamichhane ,&nbsp;Hari Prasad Lamichhane","doi":"10.1016/j.jenvrad.2024.107556","DOIUrl":"10.1016/j.jenvrad.2024.107556","url":null,"abstract":"<div><div>This study investigated the activity concentrations of ²²⁶Ra, ²³²Th, and ⁴⁰K and their soil-to-plant transfer factors in some medicinal plants located in Nepal. The geometric mean values of soil-to-plant transfer factors (TFs) for ²²⁶Ra, ²³²Th, and ⁴⁰K were 0.37, 0.96, and 3.50, respectively. This indicated that medicinal plants absorbed the highest amount of ⁴⁰K from the soil, followed by ²³²Th, while ²²⁶Ra was absorbed the least. The average radium equivalent activities for medicinal plants (189 Bq/kg) and associated soils (182 Bq/kg) were within the international acceptable limit of 370 Bq/kg. According to the activity concentrations found in the medicinal plants, they do not present any radiological health hazards unless consumed in excessive quantities; however, continuous investigations are essential.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107556"},"PeriodicalIF":1.9,"publicationDate":"2024-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142532605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Direct measurement of indoor thoron and radon progeny and estimation of inhalation dose in three cities in Gabon: Comparison of the use of thoron typical and measured equilibrium factor values","authors":"Sylvere Yannick Loemba Mouandza ,&nbsp;Saïdou ,&nbsp;W. Ndong ,&nbsp;Chutima Kranrod ,&nbsp;Masahiro Hosoda ,&nbsp;P. Ondo Meye ,&nbsp;R. Bipolo Djeune ,&nbsp;E.-D. Durastanti-Rabenga Mombo ,&nbsp;H.M.-J. Andeme-Abondhoume ,&nbsp;B.C. Mabika Ndjembidouma ,&nbsp;T.B. Ekogo ,&nbsp;G.H. Ben-Bolie ,&nbsp;Shinji Tokonami","doi":"10.1016/j.jenvrad.2024.107557","DOIUrl":"10.1016/j.jenvrad.2024.107557","url":null,"abstract":"<div><div>This study focuses on public exposure to natural radioactivity caused by the inhalation of radon and thoron progeny in homes in Franceville, Moanda and Mounana in Gabon. The equilibrium factor (<em>F</em>_<em>Tn</em>) between thoron and its progeny was determined experimentally for a proper estimate of the effective dose. In order to assess internal exposure due to radon and thoron progeny, 150 passive radon-thoron discriminative detectors (RADUET) and thoron progeny monitors were deployed for about 3 months in the above-mentioned towns. The results of the measurements obtained showed that the average concentrations of thoron progeny (EETC) were 1.54 ± 0.08 Bq <em>m</em>⁻³, 3.05 ± 0.09 Bq <em>m</em>⁻³ and 1.84 ± 0.11 Bq <em>m</em>⁻³ in Franceville, Moanda and Mounana, respectively. The ranges of the measured thoron equilibrium factors were 0.004–0.710, 0.005–0.750, and 0.006–0.794 in Franceville, Moanda and Mounana, respectively. The arithmetic and geometric mean values were, respectively, 0.183 and 0.117 in Franceville, 0.184 and 0.122 in Moanda, and 0.221 and 0.140 in Mounana. The experimentally determined equilibrium factor (<em>F</em>_{<em>T</em>nexp}) allowed us to compare the value of the experimentally determined effective dose with the theoretically determined one calculated using the equilibrium factor proposed by United Nation Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) 2000 report. <em>F</em>_{<em>T</em>nexp} values were around 6–11 times greater than the UNSCEAR typical value. The ranges, arithmetic and geometric mean EERC values determined were 30.40–55.60 Bq <em>m</em>⁻³, 24.00 ± 0.90 Bq <em>m</em>⁻³ and 41.68 (1.00) in Franceville, 36.40–62.50 Bq <em>m</em>⁻³, 45.30 ± 0.70 Bq <em>m</em>⁻³ and 44.72 (1.00) in Moanda, and 35.00–90.00 Bq <em>m</em>⁻³, 50.00 ± 2.00 Bq <em>m</em>⁻³ and 48.50 (1.00) in Mounana. The mean values of the annual effective inhalation dose due to thoron progeny determined using <em>F</em>_{<em>T</em>nexp} were 0.32 mSv (compared to 0.049 mSv), 0.63 mSv (compared to 0.103 mSv), and 0.39 mSv (compared to 0.055 mSv) in Franceville, Moanda and Mounana, respectively. The main conclusion of this study is that indirect estimations of thoron progeny concentrations considerably underestimate the estimation of the annual effective inhalation dose.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107557"},"PeriodicalIF":1.9,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142501637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dynamic models for estimating radiation doses to hydrobionts in a freshwater ecosystem","authors":"S. Fesenko","doi":"10.1016/j.jenvrad.2024.107555","DOIUrl":"10.1016/j.jenvrad.2024.107555","url":null,"abstract":"<div><div>A model of radionuclide transfer in freshwater bodies, along with dosimetric models for estimating doses to aquatic biota species (including phytoplankton, zooplankton, zoobenthos, and fish), is presented. The results of the reconstruction of radiation doses to aquatic organisms living in the closed (non-flowing, lentic) Lake Uruskul, located in the vicinity of the Kyshtym accident, are provided. The contributions of the main dose-forming radionuclides, as well as both internal and external exposures, to the doses received by aquatic organisms over the 50 years following the Kyshtym accident are discussed. It is shown that benthic organisms received the highest doses (2.6–8.3 Gy per day), while zooplankton experienced somewhat lower doses (up to 3.3 Gy per day). Fish received doses of up to 4 mGy per day during the first 100 days. Phytoplankton, with doses reaching up to 0.5 Gy per day, occupied an intermediate position in this sequence. These doses could lead to long-term radiation effects.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107555"},"PeriodicalIF":1.9,"publicationDate":"2024-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142501638","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An improved dynamic metabolic model for application to biota","authors":"A. Melintescu","doi":"10.1016/j.jenvrad.2024.107560","DOIUrl":"10.1016/j.jenvrad.2024.107560","url":null,"abstract":"<div><div>Any major nuclear facility must ensure the conservation of biodiversity regarding radiation protection of biota. A special concern is for tritium (³H) and radiocarbon (¹⁴C) transfer in wild mammals, birds and reptiles. Hydrogen and carbon are the main components of biological tissues and enter the life cycle. The present study improves the scientific bases of a previous model, analyses the uncertainty of input parameters and tests the model for a larger range of mammals and birds. The biological and metabolic half-times for organically bound tritium (OBT) and ¹⁴C are linked with energy metabolism and recent results are revised in relation with metabolic scaling. A large data base regarding basal metabolic rate (BMR), field metabolic rate (FMR), and organ mass is used for input information of the present model, which considers brain as a separate compartment. Metabolic energy partition in organs of active animal is defined and the factors affecting the metabolic rate are analysed. Body and ambient temperature, diet and habitat, and phylogeny are important factors considered in animal adaptation to environment. The available experimental data for carbon turnover rates in animals are analysed and it is observed that the experimental conditions are not appropriate for wild animals. The link between ^13,14C and ^134,137Cs turnover rate is analysed and the present metabolic approach is successfully tested for mammals and reptiles. Considering animal adaptation and the large data base for ^134,137Cs, the radiological impact of accidental releases of ³H and ¹⁴C on biota can be pursued in the future research.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107560"},"PeriodicalIF":1.9,"publicationDate":"2024-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142467201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radio-sulphur as groundwater residence time tracer – Adapting the 35S extraction approach for water samples rich in sulphate","authors":"Michael Schubert ,&nbsp;Juergen Kopitz ,&nbsp;Sabine Taeglich ,&nbsp;Christian Lucks ,&nbsp;Kay Knoeller","doi":"10.1016/j.jenvrad.2024.107553","DOIUrl":"10.1016/j.jenvrad.2024.107553","url":null,"abstract":"<div><div>Cosmogenic radio-sulphur (³⁵S) is applicable as aqueous environmental tracer for investigating sub-yearly groundwater residence times. For the purpose ³⁵SO₄ has to be extracted from large-volume water samples (ca. 20 l) and measured by liquid scintillation counting (LSC). Publications that discuss sample preparation approaches focus on waters with low or moderate sulphate concentrations based on sulphate extraction using an ion-exchange resin. However, sulphate extraction by ion-exchange is not feasible for water samples that contain total sulphate loads of over about 1500 mg. Our paper presents an approach for the preparation of water samples with sulphate loads of up to 6000 mg based on BaSO₄ precipitation directly from the sample. The key challenge of this approach is the co-precipitation of interfering natural radionuclides (²²⁶Ra, short-lived progeny of ²²²Rn, ²¹⁰Pb + progeny, ^32/33P), which complicates LSC measurement of ³⁵S. Two options are discussed to allow either pre-precipitating the unwanted radionuclides before, or keeping them in solution during Ba³⁵SO₄ precipitation.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107553"},"PeriodicalIF":1.9,"publicationDate":"2024-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142467203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}