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A study for atmospheric transport is essential for the consequence assessment of severe nuclear accidents since radionuclides could be released from the nuclear facility into the atmosphere and cause radioactive pollution in the environment. Atmospheric transport behaviors are strongly related with meteorological conditions, which can obviously influence the transport and diffusion characteristics of radioactive materials in the atmosphere; thus, it is meaningful to investigate the coupling effects between meteorological processes and transport behaviors of radioactive materials. To evaluate the influence of meteorological conditions on atmospheric transport, meteorological parameters for different seasons were first acquired by the weather research forecast model. Furthermore, atmospheric transport behaviors of radioactive materials were simulated by the meso-scale numerical model under different meteorological conditions, and numerical analyses were conducted toward transport and deposition behaviors of radioactive materials. In addition, the influence of FDDA (four-dimensional data assimilation) on meteorological parameters and atmospheric transport behaviors was researched. The present study is important for strengthening consequence assessment for severe nuclear accident and made it possible to apply the data assimilation technology in further research works. [ABSTRACT FROM AUTHOR]

The events of the 2011 Fukushima nuclear accident in Japan have garnered global concern. Despite nuclear power plants addressing numerous energy challenges, they poses substantial risks to environmental safety. The global legal basis to fulfill due regard obligations toward nuclear wastewater discharge involves international nuclear energy and marine environmental protection laws. There is substantive scope of due regard obligations toward nuclear wastewater discharge, including fulfilling international duties, prohibiting marine environmental pollution, preventing transboundary harm, and ensuring procedural obligations. The procedural obligations encompass timely notification of nuclear pollution, scientific assessment, and active consultation and cooperation with the international community. As there are still numerous obstacles to the application of due regard in the discharge of nuclear wastewater, the international marine environment frequently suffers from nuclear pollution. Considering the potential for transboundary environmental harm owing to the discharge of nuclear wastewater, this paper proposes effective solutions to this issue from the perspective of sustainable development of the marine environment. These solutions include formulating specific normative guidelines, clarifying liability for paying transboundary harm compensation, developing unified international assessment standards, and establishing an international platform for mandatory cooperation. Such solutions reinforce the national responsibility of all countries to actively fulfill their due regard obligations and effectively resolve the issue of potential irreversible damage to the marine environment. Additionally, the paper provides suggestions regarding how the international community can address the issue of Japan's nuclear wastewater discharge and other similar issues that may arise. [ABSTRACT FROM AUTHOR]

Development of effective iodine capture materials and techniques is crucial for addressing the diverse applications of iodine and its significance in various contexts, including nuclear pollution control. This study presents the creation of a new 3-Aminopropyltriethoxysilane (APTES)-modified boron nitride (BN) aerogel designed for effective iodine capture. The internal structural units of BN aerogel, specifically the one-dimensional BN fibers, have been successfully functionalized with amine groups, resulting in the formation of an amine-rich SiO x capping layer on the surface of these fibers. The APTES modification not only establishes a stable connection within the internal BN fibers network but also imparts the material with a significant number of iodine capture sites. The resulting aerogel demonstrates an impressive iodine vapor capture capacity of 313.64 wt% at 350 K and atmospheric pressure, and up to 1028.96 mg/g in iodine/n-hexane solution, surpassing the capabilities of pure BN aerogel and most existing iodine capture materials. The excellent iodine capture performance of APTES-modified BN aerogel suggests its promising potential for future applications in iodine capture. [ABSTRACT FROM AUTHOR]

The release and escape of radioactive materials has posed tremendous threats to the global environment. Among various radioactive elements, 90Sr has attracted growing attention due to its long half-life and its tendency to accumulate in bone tissue. Nonetheless, the concentration of 90Sr in radioactive waste is exceedingly low, far below the detection limits of currently available strontium-targeting chemical sensors. Herein, we propose an optical nanosensor (Sr2+-nanosensor) that exhibits an ultra-low detection limit of 0.5 nM, surpassing the 90Sr in the treated radioactive water from the Fukushima. The sensor offers wide sensing range of eight orders of magnitude, rapid response of less than 10 s, and high selectivity against 31 common ions. These excellent performances are attributed to a specific ligand (Sr2+-ligand) for Sr2+ recognition. The Sr2+ is found to be bound by six oxygen atoms from the Sr2+-ligand with a stability constant at least two orders higher than that of other traditional ligands. This study offers invaluable insights for the design of Sr2+-sensing methodologies as well as a technique for detecting trace amounts of environmental radioactive pollution. The release and escape of radioactive 90Sr has attracted growing attention due to its long half-life and its tendency to accumulate in bone tissue. Herein, the authors report an optical nanosensor (Sr2+-nanosensor) that exhibits an ultra-low detection limit of 0.5 nM, a rapid response of less than 10 s, and high selectivity against 31 common ions. [ABSTRACT FROM AUTHOR]

Groundwater is becoming more and more recognized as a crucial and indispensable water supply on a worldwide basis. The previous few decades witnessed a high increase in its demand due to the overpopulation and improving living standards. Natural radioactivity in water has garnered a lot of attention in recent years. Twenty-two groundwater samples from Kirkuk region in Iraq were tested for radon using RAD7, an electronic radon detector coupled to a RAD-H2O accessory (Durridge Co., USA) with an average value of 10.31 BqL-1, the observed radon concentration ranged from 0.18 BqL-1 to 23.005 BqL-1. The radon concentration readings that were measured fall well within the range of the maximum contamination limit (MCL) of 11.1 BqL-1 set by the EPA. The annual effective dose for individual consumer was 0.039 mSvy-1 within the public exposure limit of 1 mSvy-1 set by the WHO and UNSCEAR. Farmers can feel secure here, and the population is not particularly at risk from radon concentrations, based on the measured values for subterranean water in the study location. This study ended without considering how radon concentration is impacted by the physics of groundwater and chemical properties like PH and EC. After the sample is kept for a month, the radon concentration is recalculated.

The invasion of Ukraine and military operations around Ukrainian nuclear power plants and other nuclear facilities have prompted us to search for radiocaesium in mosses from the Kopački Rit Nature Park in Croatia, since mosses are known bioindicators of airborne radioactive pollution, and Kopački Rit is a known low radiocaesium background area. Sampling was finished in August 2023, and our analysis found no elevated radiocaesium levels. Kopački Rit therefore remains a suitable place for future detection of anthropogenic radioactive pollutants. [ABSTRACT FROM AUTHOR]

The inheritance of historic human-induced disruption and the fierceness of its impact change aquatic ecosystems. This work reviews some of the main stressors on freshwater ecosystems, focusing on their effects, threats, risks, protection, conservation, and management elements. An overview is provided on the water protection linked to freshwater stressors: solar ultraviolet radiation, thermal pollution, nanoparticles, radioactive pollution, salinization, nutrients, sedimentation, drought, extreme floods, fragmentation, pesticides, war and terrorism, algal blooms, invasive aquatic plants, riparian vegetation, and invasive aquatic fish. Altogether, these stressors build an exceptionally composite background of stressors that are continuously changing freshwater ecosystems and diminishing or even destroying their capability to create and maintain ongoing natural healthy products and essential services to humans. Environmental and human civilization sustainability cannot exist without the proper management of freshwater ecosystems all over the planet; this specific management is impossible if the widespread studied stressors are not deeply understood structurally and functionally. Without considering each of these stressors and their synergisms, the Earth's freshwater is doomed in terms of both quantitative and qualitative aspects. [ABSTRACT FROM AUTHOR]

Copyright of Kirkuk Journal of Science is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simple Summary: External dose rate measurements for I-125 permanent radioactive source implantation brachytherapy for prostate cancer requires standardized external dose rate measurements and radiation safety procedures. We developed predictive models for external dose rates to ensure compliance with radiation safety guidelines. We used Monte Carlo simulation and experimental measurements to construct an external dose rate model. The model's accuracy was validated against external dose rate measurements from clinical patients. This model facilitates the calculation and minimization of family members' radiation dose, aiding in the development of personalized radiation protection strategies. This study uses Monte Carlo simulation and experimental measurements to develop a predictive model for estimating the external dose rate associated with permanent radioactive source implantation in prostate cancer patients. The objective is to estimate the accuracy of the patient's external dose rate measurement. First, I-125 radioactive sources were implanted into Mylar window water phantoms to simulate the permanent implantation of these sources in patients. Water phantom experimental measurement was combined with Monte Carlo simulation to develop predictive equations, whose performance was verified against external clinical data. The model's accuracy in predicting the external dose rate in patients with permanently implanted I-125 radioactive sources was high (R2 = 0.999). A comparative analysis of the experimental measurements and the Monte Carlo simulations revealed that the maximum discrepancy between the measured and calculated values for the water phantom was less than 5.00%. The model is practical for radiation safety assessments, enabling the evaluation of radiation exposure risks to individuals around patients with permanently implanted I-125 radioactive sources. [ABSTRACT FROM AUTHOR]

The biological concentration effect of radionuclides in marine fish has exacerbated public anxiety about seafood security in the context of Fukushima nuclear-contaminated water discharged into the ocean. However, the most polluted port near the Fukushima Daiichi Nuclear Power Plant (FDNPP) has seldom been investigated, especially for radioactivity in marine fish. In this study, decadal observations of radiocesium in marine fish and seawater from the most polluted port were simultaneously established after the Fukushima Nuclear Accident. We found a generally decreasing trend of historical 137Cs activity in seawater, with seasonal variations modulated by precipitation. Seasonal variations were elucidated with finer detail and divided into exponential decline in the dry season and steady variation in the wet season. A novel method was proposed to estimate the continuing source term of 137Cs derived from the FDNPP, which was 3.9 PBq in 2011 and 19.3 TBq between 2012 and 2022 on the basis of historical 137Cs. The biological concentration effect of marine fish is quantitatively emphasized according to the higher ratio of overstandards for radiocesium in marine fish relative to that in seawater. Long-term observation and analysis of radiocesium in marine fish and seawater from the most polluted port would provide insights into the scientific evaluation of the effectiveness of the decommissioning of the FDNPP in the past and share lessons on the fate of Fukushima-derived radionuclides in the future. [ABSTRACT FROM AUTHOR]

Ionizing radiation covers a broad spectrum of applications. Since radioactive/radiation pollution is directly related to radiation risk, radiation levels should be strictly controlled. Different detection methods can be applied for radiation registration and monitoring. In this paper, radiation-induced variations in the optical properties of silver-enriched PVA-based hydrogel films with and without azo dye (Toluidine blue O, TBO, and Methyl red, MR) additives were investigated, and the feasibility of these free-standing films to serve as radiation detectors/exposure indicators was assessed. AgNO3 admixed with PVA gel was used as a source for the radiation-induced synthesis of silver nanoparticles (AgNPs) in irradiated gel films. Three types of sensors were prepared: silver-enriched PVA films containing a small amount of glycerol (AgPVAGly); silver-enriched PVA films with toluidine blue adducts (AgPVAGlyTBO); and silver-enriched PVA films with methyl red additives (AgPVAGlyMR). The selection of TBO and MR was based on their sensitivity to irradiation. The irradiation of the samples was performed in TrueBeam2.1 (VARIAN) using 6 MeV photons. Different doses up to 10 Gy were delivered to the films. The sensitivity of the films was assessed by analyzing the characteristic UV-Vis absorbance peaks on the same day as irradiation and 7, 30, 45, 90, and 180 days after irradiation. It was found that the addition of azo dyes led to an enhanced radiation sensitivity of the AgNPs containing films (0.6 Gy−1 for AgPVAGlyTBO and 0.4 Gy−1 for AgPVAGlyMR) irradiated with <2 Gy doses, indicating their applicability as low-dose exposure indicators. The irradiated films were less sensitive to higher doses. Almost no dose fading was detected between the 7th and 45th day after irradiation. Based on the obtained results, competing AgNP formation and color-bleaching effects in the AgPVAGly films with dye additives are discussed. [ABSTRACT FROM AUTHOR]

Hydrogen isotope permeation in structural steels can cause severe issues, including steel brittleness, fuel loss, and radioactive pollution in fusion reactors. To tackle this issue, we report a simple synthesis of α‐Al2O3/AlPO4 composite coating by the thermochemical reaction method to serve as an effective barrier hampering hydrogen isotope permeation. This coating was formed at 500°C and composed of α‐Al2O3 and AlPO4 phases. A relatively uniform and compact structure with thickness of ∼35 μm made its corrosion resistance reaching above 3000 times that of the 321 steel substrate. With just one‐side coated, the α‐Al2O3/AlPO4 coating achieved a considerable deuterium permeation reduction factor of 1935 at 450°C, three orders of magnitude higher than 321 steels. What's more, after the deuterium permeation test, no pores or cracks were generated. The excellent bonding between the coating and the substrate was resulted from the formation of CrxPy at their interface induced by Cr diffusion from the substrate. The results obtained from the current study shed new light on seeking reliable and viable ceramic coatings to tackle hydrogen permeation issues. [ABSTRACT FROM AUTHOR]

The biological impacts of the nuclear accidents in Chernobyl (1986) and Fukushima (2011) on wildlife have been studied in many organisms over decades, mainly from dosimetric perspectives based on laboratory experiments using indicator species. However, ecological perspectives are required to understand indirect field-specific effects among species, which are difficult to evaluate under dosimetric laboratory conditions. From the viewpoint that microbes play a fundamental role in ecosystem function as decomposers and symbionts for plants, we reviewed studies on microbes inhabiting soil and plants in Chernobyl and Fukushima in an attempt to find supporting evidence for indirect field-specific effects on plants and insect herbivores. Compositional changes in soil microbes associated with decreases in abundance and species diversity were reported, especially in heavily contaminated areas of both Chernobyl and Fukushima, which may accompany explosions of radioresistant species. In Chernobyl, the population size of soil microbes remained low for at least 20 years after the accident, and the abundance of plant-associated microbes, which are related to the growth and defense systems of plants, possibly decreased. These reported changes in microbes likely affect soil conditions and alter plant physiology. These microbe-mediated effects may then indirectly affect insect herbivores through food-mass-mediated, pollen-mediated, and metabolite-mediated interactions. Metabolite-mediated interactions may be a major pathway for ecological impacts at low pollution levels and could explain the decreases in insect herbivores in Fukushima. The present review highlights the importance of the indirect field effects of long-term low-dose radiation exposure under complex field circumstances. [ABSTRACT FROM AUTHOR]

As the environmental nuclear radiation pollution caused by nuclear-contaminated water discharge and other factors intensifies, more plant-microorganism-soil systems will be under long-term low-dose ionizing radiation (LLR). However, the regulatory mechanisms of the plant-microorganism-soil system under LLR are still unclear. In this study, we study a system that has been stably exposed to low-dose ionizing radiation for 10 years and investigate the response of the plant-microorganism-soil system to LLR based on the decay of the absorbed dose rate with distance. The results show that LLR affects the carbon and nitrogen migration process between plant-microorganism-soil through the "symbiotic microbial effect." The increase in the intensity of ionizing radiation led to a significant increase in the relative abundance of symbiotic fungi, such as Ectomycorrhizal fungi and Rhizobiales, which is accompanied by a significant increase in soil lignin peroxidase (LiP) activity, the C/N ratio, and C%. Meanwhile, enhanced radiation intensity causes adaptive changes in the plant functional traits. This study demonstrates that the "symbiotic microbial effect" of plant-microorganism-soil systems is an important process in terrestrial ecosystems in response to LLR. [ABSTRACT FROM AUTHOR]

This article analyzes ethnographic data that shows long-term militarization forms a significant part of state governance of the population and environment in the Arctic. Kola Peninsula, the study region, is a borderland with the West and has since the 1950s been a heavily militarized area. Applying insights from research on militarization, subjectivities, materiality, borders, and regionalism in autocratic regimes, I show how militarization shapes the environment and the lives of Indigenous reindeer herders. Despite discourses of demilitarization in the 1990s, Kola Peninsula did not move away from militarization as part of governance. The article explores what I call continuous militarization by engaging with two phenomena: (a) fencing off territories for military use and infrastructure, and (b) nuclear pollution. It discusses the interrelations of materiality and knowledge in maintaining Indigenous subjectivities and culture in line with the objectives of militarization, and shows how Russia uses participation in the Barents Euro-Arctic Region to support the objectives of militarization and justify them to the local population. The article finds that militarization is employed by the authorities to solidify the current autocratic regime among residents in the Arctic. [ABSTRACT FROM AUTHOR]

Waste-water pollution by radioactive elements such as uranium has emerged as a major issue that might seriously harm human health. Graphene oxide, graphene oxide nanoribbons, and sodium alginate nanocomposite aerogels (GO/GONRs/SA) were combined to create a novel nanocomposite using a modified Hummer's process and freeze-drying as an efficient adsorbent. Batch studies were conducted to determine the adsorption of uranium (VI) by aerogel. Aerogels composed of (GO/GONRs/SA) were used as an effective adsorbent for the removal of U (VI) from aqueous solution. Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to describe the structure, morphologies, and characteristics of (GO/GONRs/SA) aerogels. The initial concentration of uranium (VI) and other environmental factors on U (VI) adsorption were investigated, period of contact, pH, and temperature. A pseudo-second-order kinetic model can be employed to characterize the kinetics of U (VI) adsorption onto aerogels. The Langmuir model could be applied to understand the adsorption isotherm, and the maximum adsorption capacity was 929.16 mg/g. The adsorption reaction is endothermic and occurs spontaneously. [ABSTRACT FROM AUTHOR]

The article demonstrates the results of a study of the landscape structure of the Chornobyl Radiation and Ecological Biosphere Reserve (Ukr.: Chornobylskyi radiatsiino-ekolohichnyi biosfernyi zapovidnyk - ChREBR). Because of radioactive pollution, a sharp drop in human activity, and the granting of the territory the status of a protected object, the process of area rewilding took on certain characteristics and led to the return of ecosystems' natural processes. The studies cover a 7-year period from 2016 to 2022, i.e., from the moment this territory was granted protected status. That territory was abandoned by people more than 37 years ago and the former rural and urban landscapes have either already been transformed or are in the process of being transformed into natural ones. The scale of forest massifs has changed during the previous seven years, which has caused increased pasture overgrowth. huge forest massifs have been lost because of enormous forest fires and floods, particularly along the Pripet and Uzh rivers. Semi-natural successions occur in the gardens, and wooden homes are almost extinct. From orbit, a number of communities no longer resemble settlements. They are cloaked in bushes and trees instead. For places that have been ploughed, the same holds true. The last seven years show that change is happening more slowly than in the decades before. The pattern of natural processes in ecosystems, including periodic fires, the blocking of reclamation channels, and other factors, is the primary driver of changes in the composition of the land cover. [ABSTRACT FROM AUTHOR]

Today, world pollution is increasing, and many pollutants such as radioactive elements enter to environment through human activity contaminants play an essential role in human life and health. Therefore, the examination of models for dispersion caused by radioactive substances is an important issue. This article is a simulation study of the hypothetical scenario of the Zaporizhzhia Nuclear Power Plant (ZNPP) in Ukraine, which is one of the NPPs in Europe. This scenario includes the occurrence of an accident in the power plant that entry of pollutants to environment and creates an environmental disaster. The simulation of this scenario was done using the Hyspli4)Hybrid Single-Particle Lagrangian Integrated Trajectory) model and NOAA website data of ZNPP (include the wind information, temperature, humidity, and atmospheric pressure in different spatial and temporal scales) to predict and deal with pollutants. The simulation was conducted in the first week of April 2023 for 131 I and 137Cs elements, which are important elements that come out of the power plant and cause many problems. The results show the highest annual dose and concentration are 4.6 mSv/year and 2.7E+06 Bq.s/m3 respectively. It also shows that in the event of pollution, the entry of contaminated materials into the Dnieper River and the western edge of the blackened sea will bring a great disaster. Also, the eastern and northeastern regions of Ukraine, especially Kharkiv and the western borders of Russia, lead to pollution that causes radiation hazard, so the news should be shared with everyone before an actual incident occurs. [ABSTRACT FROM AUTHOR]

The article aims to assess radon concentration in various water samples, revealing levels ranging from 0.53 Bq/L to 4.68 Bq/L. Radon, specifically the isotope 222Rn, is a naturally occurring radioactive gas formed during the decay of the 238U decay series, originating from the breakdown of 226Ra. This gas is commonly found in rocks, soil, natural gas, and groundwater. Exposure to airborne and waterborne radon can increase the risk of certain cancers due to human radiation exposure. The primary Aim of this study was to assess the concentration of radon in water samples collected from diverse regions of Morocco, particularly the Midelt province and the Draa-Tafilalt region located at coordinates 32° 40' 48 North, 4° 44' 24 West. For this purpose, Solid State Nuclear Track Detectors of the LR-115 variety were used. The evaluations of annual effective dose equivalents exhibited a range spanning from 11.51 to 1.30 µSv/y, showcasing a consistent pattern of decline. Correspondingly, projections of excess lifetime cancer risk encompassed a spectrum from 4.00 to 1.98. Significantly higher risks were associated with samples S1 and S2, while notably lower risks were tied to S14 and S15. It is worth noting that all the water samples subjected to analysis registered annual effective doses that fell within the global average level recommended for ingestion exposure dose values (0.23 mSv/y) by the United Nations Scientific Committee on the Effects of Atomic Radiation. Given these results, there seem to be no radiation risks from radon gas in the study area. [ABSTRACT FROM AUTHOR]

Radioactive pollution is caused when radioactive materials are deposited in the environment or atmosphere, particularly when their presence is inadvertent, and poses harm to the environment owing to the radioactive decay of the radioactive elements. Exposure to uranium in the workplace or environment can damage cells and increase cancer risk. Uranium, a heavy metal of the actinide family, has negative consequences due to its chemical and radioactive toxicity. The fission-track method with CR-39 evaluated the uranium content in blood samples collected from healthy persons and cancer patients. This method counted the fission tracks in a detector after the nuclear reaction. The data reveal that the lowest value in the group of people with cancer is 1.84±0.36 ppb, while the highest is 2.95±0.32 ppb. This population has an average uranium content of 2.52± 0.32 ppb. The highest result was 1.88± 0.22 ppb, while the lowest was 0.39±0.15 ppb in the healthy group. This population has a mean uranium content of 1.09±0.27 ppb. The statistics show that the uranium content in cancer patients' blood is much higher than that in the blood of healthy individuals. [ABSTRACT FROM AUTHOR]

The monitoring of marine ecosystems is crucial due to the growing threat posed by nuclear power plants and other nuclear anthropogenic emissions. In our work, we used a straightforward and low-cost biomonitoring technique called fluctuation asymmetry (FA) to examine the variation between the left and right sides (developmental instability) of organisms' traits that were influenced by genetic and environmental variables in the early stages of ontogenesis. The specimens of fish (Leiognathus sp.) and crabs (Portunus sanguinolentus) were collected seasonally and used as bioindicators to determine the effects of Uranium-238 (U-238) radioactivity around a nuclear power plant. The obtained results revealed that FA values were not considered typical values (FA = 0) in all seasons. Moreover, FA values of Leiognathus sp. exhibited insignificant fluctuation for a particular characteristic through the different seasons, while a significant fluctuation occurred amongst the characteristics themselves throughout the same season. Inversely, FA values of the four characteristics in Portunus sanguinolentus displayed seasonal variation amongst them all. Statistically, there was a strong positive correlation (r = 0.5, p < 0.05) between U-238 radioactivity in the flesh of both organisms and the fluctuation asymmetry of different traits but it is not a sign that any radioactive pollution exists. [ABSTRACT FROM AUTHOR]

The radionuclide radiation risks brought on by nuclear weapons cannot be disregarded by the operators. To protect the public's health, radioactive cesium (Cs) polluted water must be treated with sustainable materials. In this work, batch adsorption studies were investigated to separate the radioactive isotope Cs-137 from the actual radioactive wastewater. In a batch adsorption method, the natural clay kaolinite was described and chosen as an adsorbent. After 2 h, equilibrium was attained with kaolinite having a removal efficiency of 75% for Cs-137. The adsorption kinetics of Cs-137 on the surfaces of kaolinite clay were assessed. The experimental kinetic data for kaolinite generated an outstanding match with the pseudo-first-order kinetic model. As a result, kaolinite was determined as the appropriate media to be adsorbent for Cs-137. [ABSTRACT FROM AUTHOR]

Many residents of the Russian Southern Urals were exposed to radioactive environmental pollution created by the operations of the Mayak Production Association in the mid- 20th century. There were two major releases: the discharge of about 1x1017 Bq of liquid waste into the Techa River between 1949 and 1959; and the atmospheric release of 7.4 * 1016 Bq as a result an explosion in the radioactive waste-storage facility in 1957. The releases into the Techa River resulted in the exposure of more than 30,000 people who lived in riverside villages between 1950 and 1961. The 1957 accident contaminated a larger area with the highest exposure levels in an area that is called the East Urals Radioactive Trace (EURT). Current epidemiologic studies of the exposed populations are based on dose estimates obtained using a Monte-Carlo dosimetry system (TRDS-2016MC) that provides multiple realizations of the annual doses for each cohort member. These dose realizations provide a central estimate of the individual dose and information on the uncertainty of these dose estimates. In addition, the correlation of individual annual doses over realizations provides important information on shared uncertainties that can be used to assess the impact of shared dose uncertainties on risk estimate uncertainty.This paper considers dose uncertainties in the TRDS-2016MC. Individual doses from external and internal radiation sources were reconstructed for 48,036 people based on environmental contamination patterns, residential histories, individual 90Sr body-burden measurements and dietary intakes. Dietary intake of 90Sr resulted in doses accumulated in active bone marrow (or simply, marrow) that were an order of magnitude greater than those in soft tissues. About 84% of the marrow dose and 50% of the stomach dose was associated with internal exposures. The lognormal distribution is well-fitted to the individual dose realizations, which, therefore, could be expressed and easily operated in terms of geometric mean (GM) and geometric standard deviation (GSD). Cohort average GM for marrow and stomach cumulative doses are 0.21 and 0.03 Gy, respectively. Cohort average dose uncertainties in terms of GSD are as follows: for marrow it is 2.93 (90%CI: 2.02–4.34); for stomach and the other non-calcified tissues it is 2.32 (90% CI: 1.78–2.9). [ABSTRACT FROM AUTHOR]

The biological impacts of the nuclear accidents in Chernobyl (1986) and Fukushima (2011) on wildlife have been studied in many organisms over decades, mainly from dosimetric perspectives based on laboratory experiments using indicator species. However, ecological perspectives are required to understand indirect field-specific effects among species, which are difficult to evaluate under dosimetric laboratory conditions. From the viewpoint that microbes play a fundamental role in ecosystem function as decomposers and symbionts for plants, we reviewed studies on microbes inhabiting soil and plants in Chernobyl and Fukushima in an attempt to find supporting evidence for indirect field-specific effects on plants and insect herbivores. Compositional changes in soil microbes associated with decreases in abundance and species diversity were reported, especially in heavily contaminated areas of both Chernobyl and Fukushima, which may accompany explosions of radioresistant species. In Chernobyl, the population size of soil microbes remained low for at least 20 years after the accident, and the abundance of plant-associated microbes, which are related to the growth and defense systems of plants, possibly decreased. These reported changes in microbes likely affect soil conditions and alter plant physiology. These microbe-mediated effects may then indirectly affect insect herbivores through food-mass-mediated, pollen-mediated, and metabolite-mediated interactions. Metabolite-mediated interactions may be a major pathway for ecological impacts at low pollution levels and could explain the decreases in insect herbivores in Fukushima. The present review highlights the importance of the indirect field effects of long-term low-dose radiation exposure under complex field circumstances.

Estimating the gamma dose rate at one meter above ground level and determining the distribution of radioactive pollution from aerial radiation monitoring data are the core technical issues of unmanned aerial vehicle nuclear radiation monitoring. In this paper, a reconstruction algorithm of the ground radioactivity distribution based on spectral deconvolution was proposed for the problem of regional surface source radioactivity distribution reconstruction and dose rate estimation. The algorithm estimates unknown radioactive nuclide types and their distributions using spectrum deconvolution and introduces energy windows to improve the accuracy of the deconvolution results, achieving accurate reconstruction of multiple continuous distribution radioactive nuclides and their distributions, as well as dose rate estimation of one meter above ground level. The feasibility and effectiveness of the method were verified through cases of single-nuclide (137Cs) and multi-nuclide (137Cs and 60Co) surface sources by modeling and solving them. The results showed that the cosine similarities between the estimated ground radioactivity distribution and dose rate distribution with the true value were 0.9950 and 0.9965, respectively, which could prove that the proposed reconstruction algorithm would effectively distinguish multiple radioactive nuclides and accurately restore their radioactivity distribution. Finally, the influences of statistical fluctuation levels and the number of energy windows on the deconvolution results were analyzed, showing that the lower the statistical fluctuation level and the more energy window divisions, the better the deconvolution results. [ABSTRACT FROM AUTHOR]

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With the wide application of nuclear energy, the problem of radioactive pollution has attracted worldwide attention, and the research on the treatment of radioactive wastewater is imminent. How to treat radioactive wastewater deeply and efficiently has become the most critical issue in the development of nuclear energy technology. The radioactive wastewater produced after using nuclear technology has the characteristics of many kinds, high concentration, and large quantity. Therefore, it is of great significance to study the treatment technology of radioactive wastewater in reprocessing plants. The process flow and waste liquid types of the post-treatment plant are reviewed. The commonly used evaporation concentration, adsorption, precipitation, ion exchange, biotechnology, membrane separation, and photocatalysis are summarized. The basic principles and technological characteristics of them are introduced. The advantages and disadvantages of different single and combined processes are compared, and the development trend of future processing technology is prospected. [ABSTRACT FROM AUTHOR]

The burial of radioactive waste in deep geological repositories has gradually imposed itself since the 1980s in various countries. Considered more stable, safe, and responsible than storage above ground, this solution is seen as a way of keeping the waste out of human reach, and of freeing oneself of the obligation to monitor repositories. However, it soon became clear that the idea of relying on the relative stability of deep geological repositories for the safe disposal of nuclear waste to remove it from the 'all too human' risks associated with history's turbulences, has produced new uncertainties, and raised new questions, given the multi-millennial time scales involved. This article presents a study of the strategies adopted by the actors in charge of radioactive waste management in the face of the temporal constraints imposed by the length of their radioactive life. More specifically, it is intended to question the representations of temporality that allow the designers of these projects to assume their responsibilities by transmitting information and warnings towards to an extremely distant future, to recipients who are not easily representable and for whom they already have a responsibility even though they do not yet exist. [ABSTRACT FROM AUTHOR]

Copyright of Veterinaria is the property of University of Sarajevo, Veterinary Faculty and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Chronic ionising radiation exposure is a main consequence of radioactive pollution of the environment. The development of functional genomics approaches coupled with morphological and physiological studies allows new insights into plant adaptation to life under chronic irradiation. Using morphological, reproductive, physiological, and transcriptomic experiments, we evaluated the way in which Arabidopsis thaliana natural accessions from the Chernobyl exclusion zone recover from chronic low-dose and acute high-dose γ-irradiation of seeds. Plants from radioactively contaminated areas were characterized by lower germination efficiency, suppressed growth, decreased chlorophyll fluorescence, and phytohormonal changes. The transcriptomes of plants chronically exposed to low-dose radiation indicated the repression of mobile genetic elements and deregulation of genes related to abiotic stress tolerance. Furthermore, these chronically irradiated natural accessions showed higher tolerance to acute 150 Gy γ-irradiation of seeds, according to transcriptome and phytohormonal profiles. Overall, the lower sensitivity of the accessions from radioactively contaminated areas to acute high-dose irradiation may come at the cost of their growth performance under normal conditions. [ABSTRACT FROM AUTHOR]

Herein, a series of conjugated microporous polymers (CMPs) were designed and synthesised at the molecular level. The results show that the adsorption-photocatalytic performance modulation was achieved by altering the electron transport bridges as well as adding electron adsorption groups on the CMPs, which improved the affinity for uranium and led to a more homogeneous distribution of electron holes and facilitated exciton dissociation. [Display omitted] • The adsorption-photocatalytic degradation of uranium by conjugated microporous polymers can be tuned at the molecular level and does not allow the addition of additional sacrificial agents. • Constructing more electron-withdrawing groups in polymers and enhancing the degree of conjugation can effectively promote charge transfer. • By designing the molecular structure, the band gap of the CMPs, as well as the exciton dissociation energy, was altered to facilitate carrier separation. • In the adsorption-photocatalytic synergistic strategy, excellent adsorption performance is a prerequisite for improving the efficiency of the strategy. • The PB3-AO has excellent conjugation and the best uranium affinity, with the best uranium removal performance, 99.8 % uranium removal in 100 min. • Before and after conditioning, the kinetic constants for uranium removal removal were elevated by a factor of ten from PB1-AO (0.0056 min−1) to PB3-AO (0.0557 min−1). Conjugated microporous polymers (CMPs) are potential materials for removing radioactive contaminants due to their unique properties. Herein, we designed and synthesized a series of CMPs at the molecular level by modifying the electron transport bridge and incorporating acceptor units based on the synergistic adsorption-photocatalysis strategy. The obtained CMPs exhibit a strong affinity for uranium, and their more homogeneous electronic structure becomes more efficient D-π-A electron transport chain contribute to a lower exciton dissociation energy. Further electronic excitation analysis based on time-varying density functional theory shows that the electron-hole distribution and intramolecular charge transfer of the CMPs are significantly optimized, thus enhancing photocatalytic activity. This study enhances the performance of the adsorption-photocatalytic uranium trapping strategy by precisely modulating in the synthesis and provides theoretical guidance for developing materials for treating nuclear pollution. [ABSTRACT FROM AUTHOR]

Safe reactor decommissioning, especially for damaged Fukushima Daiichi (1F) nuclear power plants, is vital for environmental safety. Key challenges include remotely cleaning radiation hotspots and cutting fuel debris within the damaged primary containment vessel. However, submicron radioactive Aerosol Particles (APs) can be generated, thus necessitating effective aerosol control and removal to avoid radioactive environmental pollution and reduce radiation exposure risks during 1F decommissioning. Flue gases containing submicron APs that result in environmental pollution can also generated from other industrial works, e.g., coal, mining and chemical sectors. Conventional water spray is difficult to scavenge these small APs. Although previous studies showed the effectiveness of charged droplets on accelerating aerosol removal, the charging configuration is also important to scavenging performance. Hence, this study performs aerosol scavenging experiments in our UTARTS facility with varying induction electrode designs. Experimental results show the saturation of scavenging efficiency at high voltage and indicate the importance of charging polarity. Moreover, proper configurations of electrode position, geometry and material are studied and discussed. Our findings can be beneficial for the improvement of spray system for aerosol removal to mitigate radioactivity release and minimize contaminated water production and have implications for gas purification in various environmental and chemical industries. • Electro-charged spray aerosol removal experiments are conducted at UTARTS facility. • Various electrode models are developed for improving aerosol removal efficiency. • A saturated aerosol removal efficiency is found around 10–15 kV. • Charging polarity is significant for system effectiveness at different situations. • Effects of electrode design and configuration are studied for improving spray system. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesized 2 %g-C 3 N 4 /SnS 2 -V3/CQD 1 using waste plant soot for sustainability. • Enhanced U(VI) removal with upconversion CQDs optimizing NIR light use. • Validated indirect Z-scheme mechanism for improved photocatalytic activity. • Demonstrated high reusability with stable performance over multiple cycles. • Aligned with green chemistry by converting waste into effective photocatalysts. Heavy metal U (VI) wastewater is a difficult problem in water treatment because U (VI) readily dissolves in water and exhibits significant radiotoxicity and chemical toxicity. In the current work, the photocatalytic elimination of U (VI) is realized through the application of the Z-scheme 2 % g-C 3 N 4 /SnS 2 -V3/CQD 1 photocatalytic system. The system demonstrates high removal efficiency, efficient collection ability of natural visible light and considerable upconversion performance. Employing uranyl nitrate hexahydrate (N 2 O 8 U·6H 2 O) as the simulated pollutant of heavy metal U (VI), the 2 % g-C 3 N 4 /SnS 2 -V3/CQD 1 achieved a removal rate of 98.84 % in 30 min under the condition of pH = 3, and the reaction rate constant (k) was 0.09972 min−1. Cycling stability tests demonstrated consistent performance of the photocatalyst over four repeated cycles, indicating its potential practical application in heavy metal pollution remediation. The investigation into the boosted photocatalytic activity delved into the analysis of optical properties, including the ultraviolet–visible diffuse reflection spectrum (UV–vis DRS), photoluminescence spectroscopy (PL), and ultraviolet photoelectron spectroscopy (UPS). Additionally, electrochemical tests, such as Mott-Schottky (M−S) plots, electrochemical impedance spectroscopy (EIS), and photocurrent response, were employed to unravel the underlying factors contributing to this enhancement. Furthermore, we proposed a credible catalytic mechanism for the photocatalytic system. The Z-scheme photocatalytic model serves to enhance the conveyance of photogenerated carriers, thereby mitigating the electron-hole recombination rate within the photocatalyst. This work not only provides ideas and strategies for the construction of other multi-functional composite photocatalysts, but also pioneers a novel approach for addressing heavy metal pollution. [ABSTRACT FROM AUTHOR]

Nuclear energy is playing an increasingly important role on the earth, but the nuclear plants leaves a legacy of radioactive waste pollution, especially uranium-containing pollution. Straw biochar with wide sources, large output, low cost, and easy availability, has emerged as a promising material for uranium extraction from radioactive wastewater, but the natural biomass with suboptimal structure and low content of functional groups limits the efficiency. In this work, microbial etch was first came up to regulate the biochar's structure and function. The surface of the biochar becomes rougher and more microporous, and the mineral contents (Ca, P) indirectly increased by microbial etch. The biochar was modified by calcium phosphate and exhibited a remarkable uranium extraction capacity of 590.8 mg g−1 (fitted value). This work provides a cost-effective and sustainable method for preparing functionalized biochar via microbial etch, which has potential for application to uranium extraction from radioactive wastewater. [Display omitted] • Microbial etch process constructed a large amount of Ca sites in the cotton straw. • Microbial etch facilitated the formation of calcium phosphate on the hydrothermal biochar. • The adsorption capacity of CCS-P for U(VI) was 590.8 mg g−1. • Microbial etch is a novel method for the production of high-performance uranium adsorbent. [ABSTRACT FROM AUTHOR]

Compared with polymers and nanoparticles, fatty alcohols can not only increase the stability of foam, but also maintain better foamability at pH < 2, which is beneficial to reduce waste liquid and increase decontamination efficiency for radioactive surface pollution. However, different fatty alcohols have different hydrophobic chain lengths. The effects of fatty alcohols with different chain lengths on the performance of decontamination foam were studied at pH < 2, to assist in the selection of suitable fatty alcohols as foam stabilizers. Combined with betaine surfactant and phytic acid, biomass-based foams were synthesized using fatty alcohols with different chain lengths. When the hydrophobic tail groups of the fatty alcohol and the surfactant were the same, the foam showed the best performance, including the lowest surface tension, the highest liquid film strength, the greatest sag-resistance and the best stability. However, when the hydrophobic tail groups were different, the space between adjacent surface active molecules was increased by thermal motion of the excess terminal tail segments (a tail-wagging effect), and the adsorption density reduced on the gas-liquid interface, leading to increased surface tension and decreased liquid film strength, sag-resistance and stability. The use of decontamination foam stabilized by fatty alcohols with the same hydrophobic group as the surfactant was found to increase the decontamination rate of radioactive uranium pollution from 64 to over 90% on a vertical surface. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Advanced Research in Health Sciences (JARHS) / Sağlık Bilimlerinde İleri Araştırmalar Dergisi (SABİAD) is the property of Journal of Advanced Research in Health Sciences (JARHS) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Outcrossing can be advantageous in a changing environment because it promotes the purge of deleterious mutations and increases the genetic diversity within a population, which may improve population persistence and evolutionary potential. Some species may, therefore, switch their reproductive mode from inbreeding to outcrossing when under environmental stress. This switch may have consequences on the demographic dynamics and evolutionary trajectory of populations. For example, it may directly influence the sex ratio of a population. However, much remains to be discovered about the mechanisms and evolutionary implications of sex ratio changes in a population in response to environmental stress. Populations of the androdioecious nematode Caenorhabditis elegans, are composed of selfing hermaphrodites and rare males. Here, we investigate the changes in the sex ratio of C. elegans populations exposed to radioactive pollution for 60 days or around 20 generations. We experimentally exposed populations to three levels of ionizing radiation (i.e., 0, 1.4, and 50 mGy.h−1). We then performed reciprocal transplant experiments to evaluate genetic divergence between populations submitted to different treatments. Finally, we used a mathematical model to examine the evolutionary mechanisms that could be responsible for the change in sex ratio. Our results showed an increase in male frequency in irradiated populations, and this effect increased with the dose rate. The model showed that an increase in male fertilization success or a decrease in hermaphrodite self‐fertilization could explain this increase in the frequency of males. Moreover, males persisted in populations after transplant back into the control conditions. These results suggested selection favoring outcrossing under irradiation conditions. This study shows that ionizing radiation can sustainably alter the reproductive strategy of a population, likely impacting its long‐term evolutionary history. This study highlights the need to evaluate the impact of pollutants on the reproductive strategies of populations when assessing the ecological risks. [ABSTRACT FROM AUTHOR]