Journal of environmental radioactivity最新文献

{"title":"Nonlinear and multifractal detrended fluctuation analysis of radon time series in a volcanic touristic cave","authors":"Samuel Ogunjo ,&nbsp;M. Candelaria Martín-Luis ,&nbsp;María Esther Martín González ,&nbsp;María López Pérez ,&nbsp;Pedro A. Salazar-Carballo","doi":"10.1016/j.jenvrad.2024.107550","DOIUrl":"10.1016/j.jenvrad.2024.107550","url":null,"abstract":"<div><div>Radioactive radon gas poses significant threats to human health. Understanding the complexities of radon distribution and the dynamic relationship with atmospheric parameters will help in mitigating its impact. In this study, Multifractal Detrended Fluctuation Analysis (<em>MF-DFA</em>) and chaos analysis were used to examine the fractal structure in radon gas at La Cueva del Viento, Tenerife, between January 2021 and December 2022. The results showed that radon has multifractal properties in 2021, 2022, and 2021–2022, with values of the spectrum with of about 0.43, 0.49 and 0.44 respectively. The multifractality in radon gas was found to be driven by both long-range correlations and fat-tail distribution. Radon gas concentration at La Cueva del Viento was found to be chaotic in nature, hence, long-term prediction is impossible. Meteorological parameters such as relative humidity, air temperature and pressure were found to contribute to the variation in radon gas concentration within the cave. Relative humidity was observed to have the strongest cross-correlation with radon gas in 2021, 2022, and 2021–2022. The results from this study will help in dosimetric control for both workers and visitors to the cave.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107550"},"PeriodicalIF":1.9,"publicationDate":"2024-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142432678","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":"Spatial variability in residence time of Beryllium in the Indian Ocean","authors":"Partha Sarathi Jena ,&nbsp;Ravi Bhushan ,&nbsp;Sanjit Kumar Jena ,&nbsp;Shivam Ajay ,&nbsp;A.K. Sudheer","doi":"10.1016/j.jenvrad.2024.107549","DOIUrl":"10.1016/j.jenvrad.2024.107549","url":null,"abstract":"<div><div>Residence time of an element in the ocean is a consequence of its chemical behaviour and the various biogeochemical processes governing its distribution, sources, and sinks. Precise estimation of the residence time of beryllium(Be) is necessary for its application as a tracer for understanding present and paleo-environmental processes. We utilise cosmogenic ¹⁰Be and terrestrially derived ⁹Be measurements from surface sediments to estimate the residence time of Be in the Indian Ocean. Significant variation in Be residence time is observed, which ranges between 370 and 620 years in the central Indian Ocean, 64–205 years in the Bay of Bengal, 41–117 years in the Andaman Sea, and 179–443 years in the Arabian Sea. Large heterogeneity in the residence time of Be can be attributed to its variable scavenging efficiency in different regions. Active scavenging of Be by sediment particles contributed through various major rivers draining into the northern Indian Ocean results in short residence time of Be. The results of this study have significant implications for the selection of sample sites and the use of Be as a tracer in paleo reconstructions.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107549"},"PeriodicalIF":1.9,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142400457","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":"Advancements in microbial-mediated radioactive waste bioremediation: A review","authors":"Jin Ping Tan,&nbsp;Christal Winona Clyde,&nbsp;Chuck Chuan Ng,&nbsp;Swee Keong Yeap,&nbsp;Chean Yeah Yong","doi":"10.1016/j.jenvrad.2024.107530","DOIUrl":"10.1016/j.jenvrad.2024.107530","url":null,"abstract":"<div><div>The global production of radioactive wastes is expected to increase in the coming years as more countries have resorted to adopting nuclear power to decrease their reliance on fossil-fuel-generated energy. Discoveries of remediation methods that can remove radionuclides from radioactive wastes, including those discharged to the environment, are therefore vital to reduce risks-upon-exposure radionuclides posed to humans and wildlife. Among various remediation approaches available, microbe-mediated radionuclide remediation have limited reviews regarding their advances. This review provides an overview of the sources and existing classification of radioactive wastes, followed by a brief introduction to existing radionuclide remediation (physical, chemical, and electrochemical) approaches. Microbe-mediated radionuclide remediation (bacterial, myco-, and phycoremediation) is then extensively discussed. Bacterial remediation involves biological processes like bioreduction, biosorption, and bioprecipitation. Bioreduction involves the reduction of water-soluble, mobile radionuclides to water-insoluble, immobile lower oxidation states by ferric iron-reducing, sulfate-reducing, and certain extremophilic bacteria, and in situ remediation has become possible by adding electron donors to contaminated waters to enrich indigenous iron- and sulfate-reducing bacteria populations. In biosorption, radionuclides are associated with functional groups on the microbial cell surface, followed by getting reduced to immobilized forms or precipitated intracellularly or extracellularly. Myco- and phycoremediation often involve processes like biosorption and bioaccumulation, where the former is influenced by pH and cell concentration. A Strengths, Weaknesses, Opportunities, and Threats (SWOT) analysis on microbial remediation is also performed. It is suggested that two research directions: genetic engineering of radiation-resistant microorganisms and co-application of microbe-mediated remediation with other remediation methods could potentially result in the discovery of in situ or ex situ microbe-involving radioactive waste remediation applications with high practicability. Finally, a comparison between the strengths and weaknesses of each approach is provided.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107530"},"PeriodicalIF":1.9,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142391000","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":"Estimation of soil-to-plant transfer factor across six local government areas of Kwara state, Nigeria","authors":"Adegbulugbe Samuel Kanmi ,&nbsp;Umaru Ibrahim ,&nbsp;N.G. Goki ,&nbsp;U. Rilwan ,&nbsp;M.I. Sayyed ,&nbsp;Taha Yaseen Wais ,&nbsp;Berivan F. Namq ,&nbsp;Laith Ahmed Najam","doi":"10.1016/j.jenvrad.2024.107548","DOIUrl":"10.1016/j.jenvrad.2024.107548","url":null,"abstract":"<div><div>Transfer factors (TFs) are among the necessary parameter values for the mathematical modeling of radiological pollution's environmental impact. In this study, ²³⁸U, ²³²Th, and ⁴⁰K activity concentrations and TFs were estimated in 48 soil and plant samples through gamma-ray spectrometry NaI(Tl) in six selected areas of local governments in Kwara State, Nigeria. The findings revealed that the soil and plant samples' ²³⁸U and ²³²Th activity concentrations were within the radiological safety limits. The TFs of soil to plant fell within the worldwide ranges. A set of statistical tests were applied to verify the validity of the data, such as descriptive analysis, the analysis of variance (ANOVA) test, frequency distribution, and Spearman's correlation. The study reveals a skewed distribution in data. Spearman correlation coefficient analysis indicates a moderately negative correlation between ²³⁸U, ²³²Th, and ⁴⁰K's activity concentrations and their respective TFs (TF_U, TF_Th, and TF_K). In terms of future research in the study area, it is hoped that the data from this study will contribute to improved scientific knowledge.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107548"},"PeriodicalIF":1.9,"publicationDate":"2024-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142372012","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":"Factors influencing the dissolution rate of radon gas in water","authors":"Xiongjie Zhang ,&nbsp;Li Feng ,&nbsp;Ye Zhang ,&nbsp;Yangyang Feng ,&nbsp;Bao Wang ,&nbsp;Haixian Zhou ,&nbsp;Shumin Zhou","doi":"10.1016/j.jenvrad.2024.107542","DOIUrl":"10.1016/j.jenvrad.2024.107542","url":null,"abstract":"<div><div>Measurements of radon (²²²Rn) in water are widely utilized across various disciplines, including technology, medicine, exploration, and ecological preservation. For accurate radon measurements in water, the availability of a standardized radon solution is essential. Researchers have predominantly concentrated on the radon concentration in water (RCW) once radon distribution equilibrium is achieved, rather than the rate of radon dissolution prior to equilibrium, in the development of standard radon solutions. This makes the preparation speed of the calibration standards radon solution slow, which seriously restricts the research and development of the standard device. The purpose of this paper is to investigate the correlation between the rate of radon dissolution and both the concentration of gaseous radon and the stirring speed. Four conclusions have been derived through univariate analysis. ➀ The radon concentration in water (RCW) increases with the duration of radon dissolution, eventually reaching a state of equilibrium. ➁ The increase in gas radon concentration correlates with a simultaneous rise in the rate of radon dissolution, while the time required for radon distribution equilibrium remains constant. ➂ The augmentation of the stirring speed enhances the rate of radon dissolution, Concurrently reducing the time needed for RCW to reach equilibrium.➃ When the stirring speed is excessively high, it results in substantial fluctuations in both RCW and the rate of radon dissolution. Consequently, when employing this method for the preparation of radon solutions, it is advisable to regulate the duration of radon dissolution to 30 min at a rate of 380 rad/min and 10 min at a rate of 480 rad/min. This regulation ensures the attainment of precise concentrations. Under conditions of environmental stability, manipulation of gas radon concentration alone proves sufficient for adjusting RCW . These empirical findings furnish a robust foundation for the efficient preparation of standardized radon solutions and the requisite apparatus, essential for the calibration and accuracy of radon measurement instruments.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107542"},"PeriodicalIF":1.9,"publicationDate":"2024-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142347929","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":"Applied experimental research on in-situ online monitoring instrument for soil radon in fault zone","authors":"Ying Zhao ,&nbsp;Zhi Chen ,&nbsp;Chengnan Wang ,&nbsp;Xudong Hu ,&nbsp;Zhaofei Liu ,&nbsp;Hongyi He","doi":"10.1016/j.jenvrad.2024.107546","DOIUrl":"10.1016/j.jenvrad.2024.107546","url":null,"abstract":"<div><div>As an emerging method for seismic precursory signals in underground fluid, the reliability and stability of in-situ online monitoring devices for soil radon are crucial performance indicators that are directly related to the successful implementation of continuous monitoring of soil radon in seismic areas. This study conducted laboratory testing and field applications of a new in-situ online monitoring instrument for seismic soil radon, utilizing the experimental testing conditions provided by the radon monitoring instrument detection platform of the China Earthquake Administration and the natural experimental site at Xianshuihe Fault Zone in the China Seismic Experimental Site. The results indicate that laboratory measurement repeatability of the instrument is 5.53%, the relative intrinsic error of radon volume response activity is 1.53%, and the response capability of hourly sampling at high radon volume response activity (greater than 1.0 × 10⁵ Bq/m³) lags behind the standard instrument by 2 h, essentially meeting the requirements for seismic observation. Under field conditions, the instruments exhibit good synchronization in response at different depths at the same location. However, further improvements are needed to enhance the consistency of long-term operation in the field, as well as the adaptability to outdoor self-powering, data transmission, and environmental conditions.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107546"},"PeriodicalIF":1.9,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142319161","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":"222Rn isotope as a tool for monitoring functionality of water wells","authors":"Hassen Shube ,&nbsp;Tilahun Azagegn ,&nbsp;Seifu Kebede","doi":"10.1016/j.jenvrad.2024.107529","DOIUrl":"10.1016/j.jenvrad.2024.107529","url":null,"abstract":"<div><div>In Sub-Saharan Africa, hand pump-fitted water wells (HPWs) are characterized by poor functionality marked by rapid post-construction decline in yield. A substantial number of the HPWs show a low degree of reliability and poor water quality. Monitoring changes in performance is prerequisite to inform preventive maintenance of the HPWs. Borehole performance monitoring often requires a logistically demanding pumping test procedure. Here we demonstrate the applicability of a naturally occurring Radon-222 isotope (²²²Rn) as a complementary tool to monitor post-construction performance of HPWs. We measured ²²²Rn recovery (the ratio of ²²²Rn in the HPWs to that of the aquifer) in 32 HPWs and the host aquifers. Pumping and reliability tests have been conducted on the HPWs before taking the ²²²Rn measurements. The HPWs have been classified into four functionality classes a) high yield and reliable, b) high yield but unreliable, c) low yield and reliable and d) low yield and unreliable. In the first category, there is a high ²²²Rn recovery revealing a quick through flow of groundwater in the wells. This further demonstrates the healthy functioning of boreholes without screen clogging effects and a high permeability of the aquifer material in the vicinity of the well. The fourth category shows the lowest ²²²Rn recovery revealing a slow flow of water in the well owing to low permeability, declining water level, screen clogging, poor initial design and high water stagnation in the boreholes. The substantial difference in ²²²Rn recovery between the four categories reveals the isotopic tracer can be used as a promising independent tool to monitor post-construction changes in the performance of HPWs without the need for dismantling the HPWs for inspection.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107529"},"PeriodicalIF":1.9,"publicationDate":"2024-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142318908","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":"Characterization of rock fractures for fractal modeling of radon gas transport","authors":"Abiodun Ayo-Bali ,&nbsp;Kayode M. Ajayi","doi":"10.1016/j.jenvrad.2024.107543","DOIUrl":"10.1016/j.jenvrad.2024.107543","url":null,"abstract":"<div><div>Enhancing the predictability of radon flux in fractured environments, particularly in confined spaces, is a crucial step towards mitigating the profound health risks associated with radon gas exposure. However, previous models on fluid transport through fractured rock have focused on the relationship between radon flux and aperture in fractures and faults. However, there is paucity of understanding on the influence of rock geo-mechanical properties on radon flux. In addition, there are limited methods of characterizing rocks in relation to radon flux. The numerical model presented in this study incorporated rock properties such as Young's modulus and Poisson ratio with rock aperture to develop a dimensionless radon flux for opening-mode fractures, and five dimensionless parameters (e.g., Geofluid number, Decay number, Fracgen number, Geofrac number, and Geopeclet number) were introduced to characterize fractures in terms of radon transport. Furthermore, these newly discovered relationships were used to conduct a series of flow simulations on fracture networks using the discrete fracture network model (DFN). This model establishes a quantitative framework for predicting radon flux through open-mode fractures and the influence of rock geo-mechanical properties.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107543"},"PeriodicalIF":1.9,"publicationDate":"2024-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142315698","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":"Distinct food-web transfers of 137Cs to fish in river and lake ecosystems: A case study focusing on masu salmon in the Fukushima evacuation zone","authors":"Toshihiro Wada ,&nbsp;Shingo Suzuki ,&nbsp;Tsutomu Kanasashi ,&nbsp;Kenji Nanba","doi":"10.1016/j.jenvrad.2024.107541","DOIUrl":"10.1016/j.jenvrad.2024.107541","url":null,"abstract":"<div><div>This study was conducted to elucidate the spatial and size variations, and food-web transfer of ¹³⁷Cs in freshwater fish in the upper reaches of the Ukedo River system, a highly contaminated river system flowing through the Fukushima evacuation zone. Fish collection and environmental surveys were conducted in the summer of 2020 at five forest rivers and at the Ogaki Dam reservoir (an artificial lake) with different air dose rates (mean 0.20–3.32 μSv/h). From the river sites, two salmonid species (masu salmon and white-spotted charr) were sampled, with masu salmon generally exhibiting higher ¹³⁷Cs concentrations, ranging widely (10.6 Bq/kg-wet to 13.0 kBq/kg-wet) depending on the fish size (size effect) and site. The ¹³⁷Cs concentrations in masu salmon were explained by the air dose rates, ¹³⁷Cs concentrations in water, sediments (excluding the lake site), and primary producers, with site-specific variations. In the rivers, masu salmon (fluvial type with parr marks) mainly fed on terrestrial insects with higher ¹³⁷Cs concentrations compared with those of aquatic insects, indicating that ¹³⁷Cs was transferred mainly to fish through the allochthonous forest food-web during summer. In the lake, masu salmon (lake-run type with larger size and silvery body coloration) mainly preyed on smaller fish with lower ¹³⁷Cs concentrations, demonstrating that ¹³⁷Cs is transferred to fish through the autochthonous lake food-web with biomagnification. Differences in ¹³⁷Cs concentrations among masu salmon (mean 441 Bq/kg-wet) and other fish species (mean 74.8 Bq/kg-wet to 2.35 kBq/kg-wet) were also found in the lake. The distinct ¹³⁷Cs transfers to river and lake fish were supported by stable isotope analysis: δ¹⁵N and δ¹³C values enriched stepwisely through the food-webs were, respectively, higher and lower in the lake. Our results obtained using multiple approaches clearly revealed the distinct food-web transfer of ¹³⁷Cs in river and lake ecosystems. These findings can contribute to prediction of radioactive contamination in freshwater fish in the Fukushima evacuation zone.</div></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107541"},"PeriodicalIF":1.9,"publicationDate":"2024-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0265931X24001735/pdfft?md5=ef527f6c4eeb270494244ce64ed713be&pid=1-s2.0-S0265931X24001735-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142310514","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":"Source term estimation using noble gas and aerosol samples","authors":"Paul W. Eslinger,&nbsp;Brian D. Milbrath","doi":"10.1016/j.jenvrad.2024.107544","DOIUrl":"10.1016/j.jenvrad.2024.107544","url":null,"abstract":"<div><p>Algorithms that estimate the location, time, and magnitude of a point-source atmospheric release using remotely sampled air concentrations typically use data for a single chemical or radioactive isotope. A Bayesian algorithm is presented that uses data from multiple radioactive isotopes that are all released in the same short-duration event. Data from noble gas and aerosol samplers can be used simultaneously in the model. Application to a large synthetic data set using four isotopes shows the new algorithm generally gives more accurate location and time estimates than a comparable model using a single isotope.</p></div>","PeriodicalId":15667,"journal":{"name":"Journal of environmental radioactivity","volume":"280 ","pages":"Article 107544"},"PeriodicalIF":1.9,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142274640","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}