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Each nuclear weapon test contributes to a global burden of released radioactivity. Between 1945 and 1996, more than 2,000 nuclear tests were conducted, three-quarters of which were underground. Underground nuclear tests involved placing the nuclear device in a cavity drilled or excavated beneath the surface. The goal was to contain the explosion and its effects to the immediate vicinity of the detonation point, ultimately minimizing the release of radioactive materials into the atmosphere. While these tests successfully curtailed the atmospheric release and radioactive fallout, they created dynamic responses within crustal formations caused by local shock waves from the explosion. This paper discusses the legacy of underground nuclear testing, addressing issues from containment failure to the phenomenological effects after underground detonations and the pathways of subsequent dispersal of radionuclides to the environment. [ABSTRACT FROM AUTHOR]

As nuclear technology evolves in response to increased demand for diversification and decarbonization of the energy sector, new and innovative approaches are needed to effectively identify and deter the proliferation of nuclear arms, while ensuring safe development of global nuclear energy resources. Preventing the use of nuclear material and technology for unsanctioned development of nuclear weapons has been a long-standing challenge for the International Atomic Energy Agency and signatories of the Treaty on the Non-Proliferation of Nuclear Weapons. Environmental swipe sampling has proven to be an effective technique for characterizing clandestine proliferation activities within and around known locations of nuclear facilities and sites. However, limited tools and techniques exist for detecting nuclear proliferation in unknown locations beyond the boundaries of declared nuclear fuel cycle facilities, representing a critical gap in non-proliferation safeguards. Microbiomes, defined as characteristic communities of microorganisms found in specific habitats with distinct physical and chemical properties, can provide valuable information about the conditions and activities occurring in the surrounding environment. Microorganisms are known to inhabit radionuclide-contaminated sites, spent nuclear fuel storage pools, and cooling systems of water-cooled nuclear reactors, where they can cause radionuclide migration and corrosion of critical structures. Microbial transformation of radionuclides is a well-established process that has been documented in numerous field and laboratory studies. These studies helped to identify key bacterial taxa and microbially-mediated processes that directly and indirectly control the transformation, mobility, and fate of radionuclides in the environment. Expanding on this work, other studies have used microbial genomics integrated with machine learning models to successfully monitor and predict the occurrence of heavy metals, radionuclides, and other process wastes in the environment, indicating the potential role of nuclear activities in shaping microbial community structure and function. Results of this previous body of work suggest fundamental geochemical-microbial interactions occurring at nuclear fuel cycle facilities could give rise to microbiomes that are characteristic of nuclear activities. These microbiomes could provide valuable information for monitoring nuclear fuel cycle facilities, planning environmental sampling campaigns, and developing biosensor technology for the detection of undisclosed fuel cycle activities and proliferation concerns.

The present investigation involved the collection of various construction materials from several sites throughout the Mangalore District, Karnataka, India. The concentration of radionuclides in each sample was then determined using a NaI(Tl) detector. The passive 'Can' technique method was used to determine the rate of radon exhalation in the collected samples. The activity concentration of 40K ranges from 36.53 Bq kg−1 to 80.68 Bq kg−1. The activity concentration of 226Ra ranges from 23.30 Bq kg−1 to 80.87 Bq kg−1. The 232Th activity concentration found to be lowest is 15.06 Bq kg−1 and a maximum of 38.65 Bq kg−1 in different samples. The estimated Activity Utilisation index (AUI), dose rate (D) and gamma index (Iγ) which is lower than the recommended limit. The hazard index values are below the Indian, World average and below the safety limit, which indicates that construction materials are safe to use for construction purposes. The present investigation gives insight on radiation hazards to the human population used in the selected location. [ABSTRACT FROM AUTHOR]

Current review reports coagulation-based flocculation for treatment of radioactive wastewater. At low pH, high dosages are necessary to achieve charge neutralization resulting poor separation yield. Most radionuclides coagulate and flocculate under alkaline conditions. Stirring also affects the morphology of flocs while excessive stirring re-dissolves the flocs and decreases the SEPARATION yield. Yield depends on coagulant mixing rate, pH, concentration, temperature, stirring time and rate, settling time and sedimentation rate. The commonly used coagulants are Fe and Al while Fe is famous among all coagulants. This review is useful to develop a radionuclides separation plan from environmental protection perspective in the emergency situation. [ABSTRACT FROM AUTHOR]

Purpose: The aims of this research were to assess the sources of variability of particulate FRNs (7Be, 210Pbex and 137Cs) in river channels, the influence of sediment properties such as particle size distribution (PSD) and organic matter (OM) on FRN distributions, and to discuss the implications for sediment tracing in rivers. Methods: Suspended and channel bed sediment samples were collected in the River Avon (Devon, UK) during five strategic surveys involving a wide variation of river flows, including flood conditions. Particulate matter was analysed for 7Be, 210Pbex and 137Cs by gamma spectrometry, PSD by laser diffraction, and organic constituents, total organic carbon (TOC) and total nitrogen (TN) by elemental analysis. Results: FRNs activity concentrations vary significantly both spatially, characterised by changes in activity concentrations within and between locations, and temporally, with changes during the storm hydrograph and between seasons. Variability was attributed to changes in sediment sources and, on some occasions, to significant correlation of activity concentrations with sediment properties. The results also highlighted the influence of changes in channel characteristics and the magnitude and frequency of floods on FRN distributions. Conclusion: In the context of sediment tracing, attention should be given to seasonal changes in riverine conditions that have the potential to affect 7Be and 137Cs conservativeness. Application of FRNs in sediment fingerprinting studies should be accompanied by appropriate temporal characterisation of potential sediment sources. Finally, potential contribution of 7Be-depleted sediment from channel resuspension to the suspended load should also be considered. [ABSTRACT FROM AUTHOR]

Radionuclide therapy (RT) is widely used to advanced local cancers. However, its therapeutic efficacy is limited to the radiation resistance of cancer cells. Combination therapy aims to circumvent tumor resistance, and the combination of RT with photothermal therapy (PTT), photodynamic therapy (PDT), chemotherapy (CMT), and immunotherapy has shown promising treatment outcomes. Nanotechnology holds promise in advancing combination therapy by integrating multiple therapies on a nanostructure platform. This is due to the increased surface area, passive/active targeting capabilities, high payload capacity, and enriched surface of nanomedicines, offering significant advantages in treatment sensitivity and specificity. In the first part of this review, we categorize radionuclide therapy. The second part summarizes the latest developments in combination therapies, specifically focusing on the integration of RT with PTT, PDT, CMT and immunotherapy. The last part provides an overview of the challenges and potential opportunities related to radionuclide-labelled nanoparticles for cancer combination therapy. [ABSTRACT FROM AUTHOR]

The incidence and prevalence of neuroendocrine tumours (NETs) are on the rise, but to date, only complete surgical resection is curative. Among the various therapeutic options for metastatic disease, peptide receptor radionuclide therapy (PRRT), linking a radioactive moiety to an octreotide derivative, has been shown to be highly efficacious and a well‐tolerated therapy, improving progression‐free survival and prolonging overall survival. Nevertheless, complete responses are rare, and the current β‐particle emitters have non‐optimal radiobiological properties. A new generation of α‐particle‐emitting radionuclides is being developed, with the advantages of very high energy and a short path length. We survey the most recent developments in this field, summarising the result of currently performed studies in this potentially ground‐breaking novel form of therapy for NETs. [ABSTRACT FROM AUTHOR]

Oceans are repositories of radionuclides. Radionuclides are transferred through the food chain and cause ionizing radiation hazards for marine organisms. In this study, the transfer characteristics of 226Ra, 40K, 14C, 3H, 137Cs and 90Sr in organisms at different trophic levels in the eastern coast of Yantai city were investigated. The risk of ionizing radiation to organisms was assessed using the ERICA Tool 2.0. The results show no significant changes in the concentration of any of the nuclides in the coastal area compared to the preoperation period of the nuclear power plant. The transfer factor of 137Cs, 40K, 226Ra, 14C, 90Sr and 3H at the different trophic levels of marine organisms were 2.09, 1.29, 1.17, 1.15, 1.06 and 0.74, respectively. The dose rates of ionizing radiation to organisms from six radionuclides ranged from 32.02 nGy·h-1 to 195.49 nGy·h-1 and had a mean value of 102.86 ± 57.30 nGy·h-1. The main artificial radionuclides (14C, 3H, 90Sr, 137Cs) released by nuclear power plants in the study area produced negligible radiation doses to marine organisms. However, other artificial radionuclides present in the effluents of nuclear power plants (99Tc, 110mAg and 131I) as well as other natural radionuclides (includes 210Po, 210Pb, etc) were not included, and further evaluation of these is recommended. [ABSTRACT FROM AUTHOR]

Nuclear energy is a competitive and environmentally friendly low‐carbon energy source. It is seen as an important avenue for satisfying energy demands, responding to the energy crisis, and mitigating global climate change. However, much attention has been paid to achieving the effective treatment of radionuclide ions produced in nuclear waste. Initially, advanced adsorbents were mainly available in powder form, which meant that additional purification processes were usually required for separation and recovery in industrial applications. Therefore, to meet the practical requirements of industrial applications, materials need to be molded and processed into forms such as beads, membranes, gels, and resins. Here, we summarize the fabrication of porous materials used for capturing typical radionuclide ions, including UO22+, TcO4−, IO3−, SeO32−, and SeO42−. [ABSTRACT FROM AUTHOR]

The separation of radionuclides is critical for the sustainable development of nuclear energy. It is urgent to design and prepare functionalized materials for efficient radionuclides separation. Porous materials are considered excellent candidates for the separation of radionuclides under complex conditions due to their high specific surface areas, tunable pore structures and controllable functionalities. In this review, we summarized the design, preparation and functionalization of porous materials and their application for separation of radionuclides in the past five years, discussed the separation performance and analyzed the structure-activity relationship between various radionuclides and porous materials, and systematically clarified their characterization and mechanism of different type porous materials. We also introduced the detection, irradiation and chemical toxicity of different reflective radionuclides. [ABSTRACT FROM AUTHOR]

Fast photoluminescence and scintillation with a Stokes shift larger than 1 eV is achieved in hetero‐ligand metal–organic framework (MOF) crystals comprising inorganic linking nodes and fluorescent conjugated ligands. By finely engineering the MOF composition with the use of ligands with strictly complementary emission and absorption properties and highly delocalized molecular electronic orbitals, the singlet excitons diffusion is enhanced through the ligand framework, fully exploiting both Förster and Dexter energy transfer mechanisms. This allows for the sensitization of energy acceptor ligand fluorescence by ultrafast non‐radiative energy transfer with a rate up to the THz range. This efficient antenna effect instantly activates the MOF scintillation with a Stokes shift as large as 1.3 eV in the blue spectral range, matching the highest sensitivity spectral window of the best photodetector available. This is obtained using a minimal doping level of the energy acceptor species, with a consequent elimination of emission re‐absorption that allows the achievement of a 500% increment of the MOFs scintillation efficiency and the detection of the radioactive krypton isotope 85Kr from the gas phase with an improved sensitivity compared with the reference material. [ABSTRACT FROM AUTHOR]

The development of the nuclear industry in the countries of the Arabian Gulf demands an investigation of its potential impact on the environment and human activities. It should involve routine monitoring of radionuclide from existing nuclear facilities as well as modelling of accidental release of radioactivity. Agriculture is usually considered the human activity which is the most endangered with radioactive pollution. Although the traditional concept of low-developed agriculture in the United Arab Emirates has been already described from a radioecological point of view, herein, the recent trends of agriculture are recorded. Due to climatic changes and population increase, the use of saline lands will be more pressing. Apart from it, the risk assessment for nuclear events, which was formed mainly for temperate zones, neglected another aspect of arid zones which is underground water reservoirs refilled with episodic heavy rains. The sandy or saline soils are not an effective barrier for the migration of radionuclide deposited in topsoil. A hypersaline environment could prevent the adsorption of radionuclide on soil particles and allow their high bioavailability for halophyte plants. The new principal challenges in radioecological research in arid zones are impacts on (i) saline agriculture, (ii) underground water reservoirs, and (iii) proposal for countermeasures in order to minimise the impact of radioactive contamination. [ABSTRACT FROM AUTHOR]

This article presents the results of a study of the influence of radionuclide and chemical pollution on the morphological and anatomical parameters of Calamagróstis epigéjos plants growing in the territory of "Degelen" at the Semipalatinsk Test Site (STS). Quantitative data of morphological and anatomical parameters are given, and the content of radionuclides and toxic elements in samples of plants obtained. Statistical processing of the obtained data was conducted. The results revealed that elevated concentrations of radionuclides 137Cs and 90Sr, and the calculated absorbed dose, do not have effects on plants. Changes in the anatomical parameters of leaves and stems were observed at elevated concentrations of the elements: for leaves—Al, Pb, Sr, U, Ni, Rb, Sm; for stems—Al, Cr, Cd, U, Cu, Be, Ni, Sm, Fe. The mesophyll of the leaves and the epidermis of the stems were the most exposed to toxic elements. The data of the anatomical parameters are recommended to be used as indicative parameters of plants grown in chemically contaminated areas. [ABSTRACT FROM AUTHOR]

Exploring semiconductor materials with enhanced photocatalytic activity is essential for practical applications. This review provides a comprehensive overview of the photocatalytic reaction mechanisms. The discussion highlights recent progress in perovskite oxide materials for various environmental and energy applications, including H2/O2 production, organic pollutant degradation, heavy metal removal, radionuclide removal, CO2 reduction, and N2 fixation. The structural characteristics of perovskite oxides including titanates, tantalates, niobates, ferrites, and complex perovskite oxides are discussed, focusing on current strategies to enhance their photocatalytic activity. Furthermore, recent advances in the design and development of perovskite-based photocatalytic reactors are reviewed, emphasizing their potential for increased efficiency and practical implementation. This review aims to provide insights into the abilities, research gaps, future perspectives, and recommendations for further studies of perovskite oxide photocatalysts in addressing significant environmental and energy challenges. [ABSTRACT FROM AUTHOR]

The poor prognosis of pancreatic cancer requires novel treatment options. This review examines the evolution of radiopharmaceuticals in the treatment of pancreatic cancer. Established strategies such as peptide receptor radionuclide therapy (PRRT) offer targeted and effective treatment, compared to conventional treatments. However, there are currently no radiopharmaceuticals approved for the treatment of pancreatic cancer in Europe, which requires further research and novel approaches. New radiopharmaceuticals including radiolabeled antibodies, peptides, and nanotechnological approaches are promising in addressing the challenges of pancreatic cancer therapy. These new agents may offer more specific targeting and potentially improve efficacy compared to traditional therapies. Further research is needed to optimize efficacy, address limitations, and explore the overall potential of these new strategies in the treatment of this aggressive and harmful pathology. [ABSTRACT FROM AUTHOR]

Background: The incorporation of radionuclides into peptides and larger biomolecules requires efficient and sometimes biorthogonal reaction conditions, to which click chemistry provides a convenient approach. Methods: Traditionally, click-based radiolabeling techniques have focused on classical click chemistry, such as copper(I)-catalyzed alkyne-azide [3+2] cycloaddition (CuAAC), strain-promoted azide-alkyne [3+2] cycloaddition (SPAAC), traceless Staudinger ligation, and inverse electron demand Diels–Alder (IEDDA). Results: However, newly emerging click-based radiolabeling techniques, including tyrosine-click, sulfo-click, sulfur(VI) fluoride exchange (SuFEx), thiol-ene click, azo coupling, hydrazone formations, oxime formations, and RIKEN click offer valuable alternatives to classical click chemistry. Conclusions: This review will discuss the applications of these techniques in peptide radiochemistry. [ABSTRACT FROM AUTHOR]

The Earth's environment naturally contains radioactive elements, including long-lived isotopes such as 40K, 232Th, and 238U. Excessive exposure to these elements can pose health risks to humans, animals, and plants. This research aimed to identify and quantify these radionuclides in soil samples collected from various locations within the Federal College of Education (Technical) Gusau, Zamfara State. Specifically, we focused on the School Academic Area (SAA), School Administrative Area (SADA), School Farm Area (SFMA), Students Hostel Area (SSHA), and Staff Quarters Area (SSQA). The detected radionuclide levels were compared to global acceptable limits established by the IAEA and UNSCEAR. Using a Na (Tl) detector, we examined the activity content of these elements in the soil samples. The mean average specific activities for 40K, 226Ra, and 232Th were determined to be (390.0861 ± 6.0420) Bq/kg, (22.6847 ± 2.337) Bq/kg, and (30.2855 ± 3.4990) Bq/kg, respectively. Comparison of these values with worldwide averages (40K=412 Bq/kg, 226Ra=35 Bq/kg, and 232Th=45 Bq/kg) established by the IAEA, UNSCEAR, and ICRP, as well as other global studies, indicates that both students and staff at the Federal College of Education Technical Gusau, Zamfara State, are safe from radiation hazards and can continue their studies and work without concern. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is the third most commonly occurring cancer in the United States, with higher incidence rates among Black populations. Groundwater concentrations of natural radionuclides uranium and radium have seldom been investigated in relation to CRC despite their known carcinogenicity. We investigate spatial patterns of CRC by race, and in relation to groundwater concentrations of uranium and radium, testing the hypothesis that uranium and radium in groundwater might differentially contribute to incident CRC in Black and White populations in counties of Georgia, USA. Black populations showed a higher incidence of CRC than White populations; the median incident rate difference was 9.23 cases per 100,000 (95% CI: 2.14, 19.40). Spatial cluster analysis showed high incidence clusters of CRC in similar regions for Black and White populations. Linear regression indicated there are, on average, 1–2 additional cases of colorectal cancer in counties with higher levels of radium in their groundwater, irrespective of race. Uranium was not associated with CRC. This ecologic study suggests that radium in groundwater may be linked with increased incidence of CRC, although it did not explain higher CRC incidence rates in Black populations. Further studies are needed to verify this association given the inherent limitations in the ecologic study design and the crude exposure assessment. [ABSTRACT FROM AUTHOR]

Purpose: The radionuclides pollution base on MMs (metals and metalloids) near uranium mines has been drawing broad attention, but the extent of their impact on soil and human health is still unclear. Therefore, the aim of this study was to investigate the distribution and health risk assessments of 238U, 226Ra, 232Th and 40 K base on MMs (Cr, Ni, Cu, Zn, As, Cd, and Pb) in different surface soils near an uranium mine. Materials and methods: Surface soil samples were extracted from 35 representative sites near the Lefu uranium mine. Radionuclides and MMs were measured using high-purity germanium (HPGe) N-type coaxial detector and inductively coupled plasma mass spectrometer, respectively. Pollution status was evaluated using DR, Raeq, AEDE, Hext, and ELCR for radionuclides and Pi, Igeo, RI and health risk index for MMs. Their correlation was analyzed through Pearson/Spearman correlation analysis. Results and discussion: The average activity concentration of 238U, 226Ra, 232Th, and 40 K are 504, 1227, 118, and 769 Bq·kg−1 respectively and the average concentration of Cr, Ni, Cu, Zn, As, Cd, and Pb are 200, 33.9, 41.3, 132, 18.4, 0.26, and 78.7 mg·kg−1, respectively. Values of DR, Raeq, AEDE, Hext, and ELCR all exceed the world average to varying degrees and values of Pi, Igeo, RI and the health risk index are within the acceptable ranges. Correlation analyses showed that 238U, 226Ra, 232Th and Pb are strongly correlated (correlation coefficient > 0.6) with each other. Conclusions: On the basis of the obtained values, it can be concluded that generally higher radionuclides and MMs were distributed near the Lefu uranium. There are potential health risks associated with the elevated radioactivity. The overall situation of MMs is controllable, however, particular attention is warranted for Cr and Cd, as they approach values-at-risk. The strong correlations between 238U, 226Ra, 232Th and Pb imply a uniform pollution level or a possible shared source. [ABSTRACT FROM AUTHOR]

Abstract Radionuclide therapy (RT) is widely used to advanced local cancers. However, its therapeutic efficacy is limited to the radiation resistance of cancer cells. Combination therapy aims to circumvent tumor resistance, and the combination of RT with photothermal therapy (PTT), photodynamic therapy (PDT), chemotherapy (CMT), and immunotherapy has shown promising treatment outcomes. Nanotechnology holds promise in advancing combination therapy by integrating multiple therapies on a nanostructure platform. This is due to the increased surface area, passive/active targeting capabilities, high payload capacity, and enriched surface of nanomedicines, offering significant advantages in treatment sensitivity and specificity. In the first part of this review, we categorize radionuclide therapy. The second part summarizes the latest developments in combination therapies, specifically focusing on the integration of RT with PTT, PDT, CMT and immunotherapy. The last part provides an overview of the challenges and potential opportunities related to radionuclide-labelled nanoparticles for cancer combination therapy. Graphical Abstract

Ionizing radiation, emanating from decaying nuclides, poses potential biological harm to human organs. Wadi B, a village within the Jere local government area of Borno State, Nigeria, is currently undergoing oil exploration activities. This study was conducted to evaluate the outdoor gamma radiation levels at the Wadi B oil exploration site. Utilizing a portable hand dosimeter (Radiation Alert Inspector), gamma exposure levels (GEL) were measured across sixteen (16) spots within the exploration site. Results revealed that the gamma exposure levels measured in the boreholes FYM (1 to 8), range from 0.17- 0.27 Mr/hr, with an average of 0.21 Mr/hr while, the levels around the wells FYM (9 to 16) vary from 0.14- 0.25 Mr/hr, with an average of 0.18 Mr/hr. The estimated annual effective dose (AED) varied from 0.24528 to 0.47304 μSv/yr, averaging at 0.3460 μSv/yr. Notably, the average values of Total Dissolved Solids (TDS), Conductivity, and Gamma radiation exceeded the recommended limits established by the World Health Organization (WHO, 2006), which are 400 μS/cm for conductivity, (50-150) ppm for TDS, and 0.002 mR/hr for radiation doses, respectively. However, the calculated Excess Lifetime Cancer Risk (ELCR) values were lower than the proposed world average level of 70 μSv/yr by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). This study suggests a heightened risk of exposure to outdoor ionizing radiation among inhabitants residing near the study locations

The study focused on syenogranite and its altered variety, and specifically monitored the activities of 226Ra, 232Th, and 40K using NaI(Tl) gamma-ray spectroscopy. Syenogranites in the study area in Egypt were investigated to determine their potential use in industries such as ornamental stones and ceramics. The main outcrops in the study area consist of metasediments, metavolcanics, metagabbro, syn-to late-orogenic granites, and post-orogenic granites (syenogranites). There are also numerous dikes and veins of various shapes and compositions that have intruded and penetrated all the older rocks in the area. The mean activity (± standard deviation, SD) of these radioelements in the granites is 226Ra (63 ± 71 Bq kg−1), 232Th (76 ± 170 Bq kg−1), and 40K (1248 ± 532 Bq kg−1) were found to be greater than the world average. The radiological hazards are mostly attributed to the γ-rays emitted by granitic rocks. The granites studied in this study deviate from international standards mainly due to the presence of minerals containing radioelements such as zircon, allanite, monazite, sphene titanite, apatite, thorite, samarskite, fergusonite, xenotime, columbite, apatite and fluorite. As a result, granitic rocks are unsuitable for home building.

The transformation of radioactive contamination of agricultural lands with 137Cs isotope is one of the evidences of soil erosion. Changes in the radionuclide content and the corresponding rates of soil loss can be assessed quantitatively by repeated soil sampling at key sites over long time intervals. Being highly labor-consuming, such studies are few in number; they have not been conducted previously in the zone of intense Chernobyl contamination in the Central Russia. The method of repeated sampling (resampling) was used in 2023 within the plowed slopes of a small catchment in the southern part of Tula region, 26 years after the first sampling in 1997. The changes in 137Cs deposits (kBq/m2) that occurred during this period turned out to be statistically significant, with an average reduction of more than 10%. According to a proportional erosion conversion model based on relative changes in 137Cs deposits, the average annual rate of washing off was estimated at 11.7 t /ha. Such values of soil loss are comparable in general with the previously published results of independent mathematical modeling for this area. Thus, the use of resampling method, including that at new sites, appears to be promising for assessing the rate of soil loss. In addition, it permits us to verify the existing erosion models and to trace long-term trends in the spatial transformation of radioactive contamination. [ABSTRACT FROM AUTHOR]

In nuclear medicine radionuclides are used in diagnosis and therapy. They can be produced in cyclotrons with different nuclear reactions. Overall goal is the optimization of the yield of the desired radionuclide which is possible by changing different experimental parameters. To test the influence of these parameters to obtain an optimal yield, simulation programs like PHITS and FLUKA can be used. In first studies (see Klink et al. [Testing the suitability of FLUKA and PHITS to predict the outcome of radionuclide production. Radiat. Eff. Defects Solids2023, 178 (1–2), 111–125]) the experimental yields of nuclide productions were compared with simulation results of different target designs with perpendicular and inclined configuration. In this paper we focus on the effect of inclination since it was one of the problematic cases of the previous study [Klink et al. Testing the suitability of FLUKA and PHITS to predict the outcome of radionuclide production. Radiat. Eff. Defects Solids2023, 178 (1–2), 111–125]. Different beam profiles were varied in the simulations to determine its influence on the simulated yields. The choice of the beam profile has a great influence on simulating irradiations of inclined targets. With a known beam profile and other experimental conditions, FLUKA can be used to simulate nuclide productions of inclined targets with small deviations compared to the experimental yields. In conclusion, FLUKA can be used to determine the yield of unknown nuclide production with different target designs. [ABSTRACT FROM AUTHOR]

Radionuclides and heavy metals/metalloids content in soils and shore sediments of Al-Negila area (Matrouh, Egypt) were determined to assess the associated environmental risks. A total of 46 soil and shore sediment samples were collected and analysed for natural and man-made radionuclides (238U series, 232Th series, 40K and 137Cs) and heavy metals/metalloids (Al, B, Ba, Ca, Cd, Co, Cr, Cu, Fe, Mn, Ni, Si, Sr, Zn, and Hg). Within the study area, the soil and shore sediments are mainly calcareous with sandy, sandy clay and silty clay sized textures. The radionuclides and metals/metalloids concentrations in the soil were higher than those in the shore sediments, meanwhile, they are within the safe world average values. The estimated average (±SD) activity concentrations of 226Ra, 228Ra, 40K and 137Cs were 20.3 ± 5.3, 17.8 ± 6.3, 353.1 ± 129.8, and 2.7 ± 2.7 Bq/kg, respectively. The activity concentration of 137Cs is characterised by the greatest variability characterising the fallout deposited radionuclides. The estimated average values of Raeq (72.9 ± 23.7 Bq/kg), air absorbed gamma dose rate (34.9 ± 11.4 nGy/h), annual effective dose (42.8 ± 14.0 µSv/y), and external hazard index (0.2 ± 0.1) are lower than the international averages reported by UNSCEAR 2008. The average concentrations (mg/kg) of heavy metals/metalloids in soil samples decrease in the following order: Mn (129.8) > Sr (95.0) > Si (28.8) > Ba (25.7) > Zn (25.1) > Cr (17.6) > B (10.0) > Ni (3.9) > Cu (3.3) > Co (0.5) > Cd (0.007) > Hg (7.0 µg/kg). According to the classes of pollution load and contamination degree indices, soils and shore sediments of Al-Negila area are generally uncontaminated. However, a few sampling sites were considered moderately contaminated with B, Cd, and Sr. The radionuclides and heavy metal/metalloid contents in the soil and shore sediments of the area should be observed and assessed regularly, especially for 137Cs. [ABSTRACT FROM AUTHOR]

Soil radioactivity is a poorly recognized form of land degradation; however, there are regions all around the world where it can be dangerous to the environment and human health. The aim of the study was to analyze the radioactivity of Technosols developed on thermal power station (TPS) ash disposal sites. Total concentration of uranium (U), thorium (Th), and cesium (Cs), as well as the radioactivity of select radionuclides in Technosols were determined to recognize the level of radioactivity and to assess the potential radiological health risk. Total U, Th and Cs concentrations in Technosols were in ranges 1.5 to 11.3, 4 to 22.9, and 0.2 to 21.3 mg·kg−1, respectively. The radioisotope activities in Technosols (in Bq·kg−1) were in the 1.6–25.5 (137Cs); 29.2–1265 (40K); 26.2–99.9 (228Th); 27.9–100 (228Ra); 20.5–134. (226Ra); 32.8–177 (210Pb); 23.9–144 (238U); 1.2–7.0 (235U) ranges. The activity concentrations were slightly higher than the activities of non‐contaminated soils. Technosols developed from bituminous coal ash had higher 40K, 228Th, and 228Ra activity concentrations than soils developed from lignite ash. Artificial 137Cs occurred in surface horizons of Technosols due to fall of atmospheric dust enriched in 137Cs. Annual effective dose (AED) in Technosols amounted 0.07–0.16 mSv·a−1 and was somewhat higher than the global and Polish average (0.06 and 0.07 mSv·a−1, respectively) for outdoor external terrestrial radiation. The radioactivity of the investigated Technosols is slightly above the average radioactivity of native soils. The radiological human‐health risk related to the analyzed soils is low. [ABSTRACT FROM AUTHOR]

The work examines the state of 106Ru in solutions simulating technological media and liquid radioactive waste from nuclear power plants with a VVER reactor, as well as the influence of the physicochemical state of the radionuclide on the efficiency of ion exchange and ultrafiltration treatment methods. During the study, the regions of existence of ionic and nonionic states of the radionuclide were explored in solutions of complex composition. In addition, the size distribution of particles containing 106Ru were established. The formation of complex compounds of 106Ru with polyborate ions in the neutral and slightly alkaline pH region has been shown, which leads to a decrease in the efficiency of decontamination of liquid radioactive waste from ruthenium radionuclides. [ABSTRACT FROM AUTHOR]

To establish the radioactivity level of soils and assess the associated radiological impact on residents, 58 samples from the town of Bitola and its environs were collected. After conducting gross alpha and gross beta measurements with a gas-flow proportional counter as a preliminary screening test, subsequent gamma-spectrometry measurements reveal the presence of 40K, 226Ra, 232Th, and 137Cs in the soil samples as radionuclides with the highest impact. The absorbed gamma dose rate, the annual effective dose, radium equivalent activity, external hazard index, gamma index, excess lifetime cancer risk, and annual gonadal dose were calculated using the obtained activity concentrations of the radionuclides. Upon comparison with similar studies conducted in the Balkan countries, the obtained results for radiation hazard indices were found to be the highest in the region. Coloured maps were generated to visually represent the spatial distribution of the absorbed gamma dose rate in air and annual effective dose, clearly indicating the combined influence of geology and human activities, including the nearby thermoelectric power plant operation. [ABSTRACT FROM AUTHOR]

According to reports, exposure to high concentrations of naturally occurring radioactive substances like Uranium-238, Thorium-232, and Potassium-40 poses serious health concerns. This review study aims to report the concentrations of radionuclides in various South African soil and their equivalent risk assessments, which have been sparingly reported. For South Africa, most radionuclide concentrations above the permissible limits of 33, 45, and 420 Bq.kg−1 for 238U, 232Th, and 40K, respectively, have been found in some soil samples taken near industrialization activities, including mining and oil exploration and production. Thus, the amount of radionuclides is a good indicator of the kind of soil, the local geology, and the mineral make-up of the parent rocks. The increases in radiation exposure to people and the environment have been reported to cause various radiological health hazards. Thus, this review study can be used as a data source to track probable radioactive contamination from soils found in South Africa. [ABSTRACT FROM AUTHOR]

Background: It is known that various natural (40K, 234Th, 231Th, etc.) and technogenic (90Sr, 89Sr, 137Cs, 134Cs, etc.) radionuclides (RN) may enter into the biosphere during the operation of nuclear power plants (NPP). Moving along the transfer chains of irrigation water -- soil - plant and hydroponic nutrient solution -- substrate - plant, the RN may penetrate human organisms and potentially cause various dangerous diseases. Thus, monitoring the gross β- radioactivity of plant materials (such as vegetables, medicinal plants, fruits, etc.) and ensuring the production of radioecologically safe plant raw materials is a contemporary challenge.Since 1996, we have been conducting radiomonitoring studies in Ararat Valley in the water-soil-plant ecosystem of the zones within the 2-15, 20, and 30 km radius of Armenian NPP (ANPP) technogenic influence. Objective: To reveal the optimal conditions for radio-ecologically safe plant raw material, we compared the gross β-radioactivity of the edible parts of several valuable vegetables (rhubarb - Rheum undulatum L., Chinese cabbage - Brassica rapa subsp. Chinensis, kale - Brassica oleracea var. Sabellica L., spicy pepper - Capsicum frutescens L., (varieties - "Bishops crown", "Cayenne", "Chili De arbol", "Little Elf", "Fresno"), cicer - Cicer arietinum L., (varieties - "Kapuli" introduced from the USA, "Desi" introduced from Canada and "Leningradskaya 313" introduced from Russia)) as well as the plant raw materials of medicinal plants (ashwagandha - Withania somnifera L., Moroccan mint - Mentha spicatavar. Crispa, Marokko, Japanese pagoda tree - Sophora japonica L., holy basil - Ocimum tenuiflorum L., and rosemary - Rosmarinus officinalis L.). These plants were introduced into Armenia and grown under various outdoor hydroponic systems (organic, NFT, water stream, drip, and classical hydroponics) and in soil.hydroponics) and soil. The studies were done at the Institute of Hydroponics Problems (IHP) in Ararat Valley (a zone of ANPP with a 30 km radius). It has concrete practical significance since it allows radio-ecologically safe plant raw material to be received. Methods: The gross β-radioactivity of the plant samples was determined using a small background UMF-1500 radiometer. Results: The results of the radiochemical study have shown that in the same zone of radio voltage and climatic conditions of Ararat Valley, several varieties of crops cultivated in hydroponic and soil conditions have accumulated different amounts of β-emitting technogenic and natural RN. The gross β-radioactivity of vegetables fluctuated between 230 - 590 Bq/kg in classic hydroponics and 140 - 480 Bq/kg in soil, and the gross β-radioactivity of medicinal plants was between 320 - 680 Bq/kg in hydroponics and 240 - 450 Bq/kg in soil. In both hydroponic systems and soil, the gross β-radioactivity of the edible parts of vegetables and medicinal plants follows the same decreasing order: for vegetables, the order is rhubarb > Chinese cabbage > kale > spicy pepper > chickpea; and for medicinal plants, the order is ashwagandha > Moroccan mint > holy basil > Japanese pagoda tree > rosemary. Conclusion: Regardless of the crop varieties and cultivation methods (organic, water stream, drop, classical hydroponics, and soil culture), the plant raw material is considered radio-ecologically safe because their gross β- radioactivity doesn't exceed the radio-ecological safety threshold stated by the World Health Organization -- 1000 Bq/kg. [ABSTRACT FROM AUTHOR]

Fresh water outflows to sea are a source of marine contamination by radionuclides, most originating from nuclear industry operations. Usually, these lead to small amounts of radionuclides entering the sea, for example, because of the discharge of cooling water. However, under accident conditions large amounts of radionuclides may enter river systems. The extent of radionuclide transport along freshwater systems and their subsequent dispersal in the ocean depends upon their speciation. This manuscript examines the speciation of uranium, with particular reference to sulphate complexes, along the Shu River in Central Asia with a view to predict its transport along such rivers to receiving seas. The speciation of uranium isotopes in the Shu River (at the border of Kazakhstan and Kyrgyzstan) was determined. Calculations were based on the measured concentrations of Ca2+, Mg2+, Na++K+, HCO3−, Cl−, SO42−, and of uranium isotopes. These calculations were determined by either titrimetric methods, gravimetric methods or, for uranium isotopes, by alpha-particle spectrometry. Almost all uranium was present as one of three soluble complexes, either [UO2OH]+, [UO2(CO3)2(H2O)2]2− or [UO2(CO3)3]4−. However, despite the significant concentration of sulphate-ions in the water, especially for the Lower Shu in Kazakhstan, the probability of uranium being present as of sulphate complexes in the analyzed water was very low. The presence of soluble ions is consistent with their mobility along freshwater systems and their transfer to the marine environment. No evidence of an effect from influxes of sulphate was identified. [ABSTRACT FROM AUTHOR]

Radioactive materials may contain primordial radionuclides, and radionuclides of anthropogenic, nuclear accident, and waste disposal which are present in marine environments. This review explores various approaches for the effective sampling and detection of marine radionuclides. The different types of samples that can be collected, including water, sediment, biota, and suspended particulate matter are discussed. Additionally, this paper discusses the various analytical techniques employed for radionuclide detection, such as gamma spectrometry and radiochemical separation. The review emphasizes the importance of choosing appropriate sampling and detection methods based on the specific radionuclides, environmental conditions, and the desired level of sensitivity. It also highlights the challenges associated with their sampling and detection in complex marine environments. These include low radionuclide concentrations, interference from natural matrices, and contamination risks. [ABSTRACT FROM AUTHOR]

There is a growing need to understand the potential ecological impacts of contaminants in offshore oil and gas infrastructure, especially if that infrastructure is to be left in situ as a decommissioning option. Naturally occurring radioactive material (NORM) is one type of contaminant found in solid deposits on internal surfaces of infrastructure that poses potential ecological harm if released into the marine environment. Microbes are important components of marine sediment ecosystems because they provide ecosystem services, yet the impacts of NORM contamination to these communities are not well understood. The present study aimed to investigate the response of benthic microbial communities to NORM‐contaminated scale, collected from an offshore oil and gas system, via controlled laboratory microcosm studies. Changes to microbial communities in natural sediment and sediments spiked with NORM at radium‐226 activity concentrations ranging from 9.5 to 59.8 Bq/kg (in partial equilibria with progeny) over 7 and 28 days were investigated using high‐throughput sequencing of environmental DNA extracted from experimental sediments. There were no significant differences in microbial community composition between control and scale‐spiked sediments over 7 and 28 days. However, we observed a greater presence of Firmicutes in the scale‐mixed treatment and Chloroflexi in the scale‐surface treatments after 28 days. This could suggest selection for species with contaminant tolerance or potential resilience to radiation and metal toxicity. Further research is needed to explore microbial tolerance mechanisms and their potential as indicators of effects of radionuclide‐contaminated sediments. The present study demonstrated that microcosm studies can provide valuable insights about the potential impacts of contamination from oil and gas infrastructure to sediment microbial communities. Environ Toxicol Chem 2024;43:1648–1661. © 2024 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. [ABSTRACT FROM AUTHOR]

Terrestrial and extraterrestrial radioisotope research has been strongly dependent on the development of analytical methods which would enable to trace radioisotopes at low concentrations in subgram samples (e.g., in tree rings, ice cores, meteorites, etc.). Accelerator mass spectrometry (AMS) has become the most sensitive technique for ultralow-level analysis of long-lived radioisotopes, such as 14C, 10Be and 26Al. We review developments and applications carried out in the CENTA laboratory, and describe a recently installed fully equipped AMS line, designed for analysis of long-lived radioisotopes from tritium to curium. [ABSTRACT FROM AUTHOR]

Heavy metal contamination of food products has recently become a significant health concern. The widespread availability of dietary supplements increases the interest of health-conscious consumers in these food products. As a result, the consumption of dietary supplements is growing worldwide owing to their potential health benefits. However, dietary supplements may also contain other elements, including toxic ones, and thus affect human health. Previous studies have shown that they contain the radionuclides polonium, lead, uranium, and thorium, making them a source of internal exposure related to the decay of the isotopes studied. For this reason, the radiation safety associated with the presence of the radioactive isotopes 210Po, 210Pb, 234U, 238U, 230Th, and 232Th in calcium and magnesium supplements for adults was estimated, namely the cancer risk associated with their consumption and the risk of cancer-related death. Cancer morbidity and mortality risk ranged from 10-5 to 10-10. The highest cancer risk morbidity and mortality was calculated for 210Po and 210Pb due to higher activities and radiotoxicity. The effect of the lower concentrations of 234U, 238U, 230Th, and 232Th in the supplements analyzed is a significantly lower risk of cancer due to their consumption and activities in the product. The study showed that both effective doses and cancer risks were low, and calcium and magnesium supplements can be considered safe for human consumption. [ABSTRACT FROM AUTHOR]

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Microplastics and radionuclides create considerable obstacles for the sustainable management of aquatic systems. The interactions between uranium-232 and americium-241 with two microplastics, specifically polyurethane (PU) and polylactic acid (PLA), have been explored in aqueous matrixes mimicking seawater and wastewater. The tests were performed at different pH levels (4, 7, 9) and the remediation efficiency was evaluated predominately as a function of temperature. An increase in temperature positively influences the sorption of uranium and americium. The highest removal performance for both uranium and americium was observed in the neutral (log(Kd)PLA=1.6 and log(Kd)PU=1.7 for U; log(Kd)PLA=1.7 and log(Kd)PU=1.6 for Am) and alkaline (log(Kd)PLA=1.4 and log(Kd)PU=1.3 for U; log(Kd)PLA=1.8 and log(Kd)PU=1.9 for Am) pH ranges, respectively. In seawater mimicking water samples (pH ∼8), the adsorption efficiency declines significantly (log(Kd)PLA=1.1 and log(Kd)PU=1.2 for U; log(Kd)PLA=1.3 and log(Kd)PU=1.4 for Am) due to competitive interactions arisen from other metals/ions found in natural waters (e.g., Ca2+) and the stabilization of actinides (particularly uranium) in solution (e.g., UO2(CO3)34-). The composition of the water matrixes, which govern both actinide speciation and the types of surface-active sites, is strongly linked to the thermodynamics of surface adsorption and determines the values of the associated parameters (ΔΗ° and ΔS°). Generally, the ΔS° and ΔΗ° values were found positive, indicating that the interactions are entropy-driven. However, in the case sorption of U(VI) in seawater samples by PLA, both ΔS° and ΔΗ° became negative, denoting enthalpy-driven binding mechanisms associated with a decrease in randomness on the MP’s surface upon adsorption.

Oceans are repositories of radionuclides. Radionuclides are transferred through the food chain and cause ionizing radiation hazards for marine organisms. In this study, the transfer characteristics of 226Ra, 40K, 14C, 3H, 137Cs and 90Sr in organisms at different trophic levels in the eastern coast of Yantai city were investigated. The risk of ionizing radiation to organisms was assessed using the ERICA Tool 2.0. The results show no significant changes in the concentration of any of the nuclides in the coastal area compared to the preoperation period of the nuclear power plant. The transfer factor of 137Cs, 40K, 226Ra, 14C, 90Sr and 3H at the different trophic levels of marine organisms were 2.09, 1.29, 1.17, 1.15, 1.06 and 0.74, respectively. The dose rates of ionizing radiation to organisms from six radionuclides ranged from 32.02 nGy·h-1 to 195.49 nGy·h-1 and had a mean value of 102.86 ± 57.30 nGy·h-1. The main artificial radionuclides (14C, 3H, 90Sr, 137Cs) released by nuclear power plants in the study area produced negligible radiation doses to marine organisms. However, other artificial radionuclides present in the effluents of nuclear power plants (99Tc, 110mAg and 131I) as well as other natural radionuclides (includes 210Po, 210Pb, etc) were not included, and further evaluation of these is recommended.

Diatoms and bacteria play a vital role in investigating the ecological effects of heavy metals in the environment. Despite separate studies on metal interactions with diatoms and bacteria, there is a significant gap in research regarding heavy metal interactions within a diatom-bacterium system, which closely mirrors natural conditions. In this study, we aim to address this gap by examining the interaction of uranium(VI) (U(VI)) with Achnanthidium saprophilum freshwater diatoms and their natural bacterial community, primarily consisting of four successfully isolated bacterial strains (Acidovorax facilis, Agrobacterium fabrum, Brevundimonas mediterranea, and Pseudomonas peli) from the diatom culture. Uranium (U) bio-association experiments were performed both on the xenic A. saprophilum culture and on the four bacterial isolates. Scanning electron microscopy and transmission electron microscopy coupled with spectrum imaging analysis based on energy-dispersive X-ray spectroscopy revealed a clear co-localization of U and phosphorus both on the surface and inside A. saprophilum diatoms and the associated bacterial cells. Time-resolved laser-induced fluorescence spectroscopy with parallel factor analysis identified similar U(VI) binding motifs both on A. saprophilum diatoms and the four bacterial isolates. This is the first work providing valuable microscopic and spectroscopic data on U localization and speciation within a diatom-bacterium system, demonstrating the contribution of the co-occurring bacteria to the overall interaction with U, a factor non-negligible for future modeling and assessment of radiological effects on living microorganisms.