Nuclear Accident Research Articles

Calcium carbonate/ε-poly(lysine) hybrid microparticles for uranium seawater extraction: an eco-compatible emergency response to marine nuclear disasters

During the past decade, a large variety of materials dedicated to uranium seawater extraction has been developed for harvesting purposes. Yet, materials especially designed for decontamination following nuclear accidents are scarce and eco-friendly ones even rarer. In this study, hybrid microparticles made of biocompatible calcium carbonate and ε-poly(lysine) are used as efficient U sorbent in seawater. Their eco-friendly nature makes them interesting for both harvesting and on-site immobilization of radionuclides, also accounting their ability to settle in the seabed with limited impact on eco-systems. The material shows excellent U extraction capability in contaminated seawater ([U] = 10 ppm) with removal rate R of 87.7 % and extraction capacity of 513 mg per g of ε-poly(lysine) and remains efficient in natural condition ([U] = 2.8 ppb) with R = 39.8 %. In addition, the sorbent has a remarkable selectivity toward U versus V in U contaminated seawater as well as a significant affinity for Sr2+. DFT and XPS analyses revealed that U is adsorbed to ε-poly(lysine) via a chelation mechanism that involves amide and amine groups of lysine. Lability of the formed coordination complex allows easy recovery of captured U by contact with NaHCO3 desorbing solution, ensuring recyclability of the material.

Adaptation of FDMT to include process-based models and consider regional aspects following radionuclide deposition events

Experience from earlier nuclear accidents has clearly shown the need for maintaining and developing appropriate modelling capabilities. Dealing with complex issues such as human exposure following a nuclear accident necessitates the implementation of a set of interconnected models such as FDMT. FDMT is an integrated module within the two main European decision support systems for radiological emergency preparedness, ARGOS and JRODOS, to simulate the transfer of radionuclides along terrestrial food chains and to predict their activity concentrations in foodstuffs. In order to make the module more fit-for-purpose, FDMT has been implemented in a new modelling platform (ECOLEGO) which provides a high degree of flexibility with regard to conducting developmental work. This paper presents improvements in FDMT further through either the incorporation of new models or further elaboration of existing ones, as well as updates in default parameters. Models have also been made more fit-for-purpose through consideration of regional-specific parameters. Specific improvements include modelling developments related to dry deposition, radioactive particle weathering, radiocaesium transfer influenced by soil characteristics and, for a region-specific case, animal uptake. In addition, the paper presents new pathways and parameters (and updated values) to be considered for making FDMT more adapted for Norwegian conditions. Overall, the improvements made in the present work should significantly reduce the uncertainties associated with the outputs of the FDMT models.

A Call for Curriculum Development to Prepare Medical Students and Residents to Assist with Mass Casualties after a Catastrophic Radiological or Nuclear Incident.

A Call for Curriculum Development to Prepare Medical Students and Residents to Assist with Mass Casualties after a Catastrophic Radiological or Nuclear Incident.

Selecting the Most Relevant Mouse Strains for Evaluating Radiation-Induced Multiple Tissue Injury after Leg-Shielded Partial-Body Gamma Irradiation.

Animal studies are needed that best simulate a large-scale, inhomogeneous body exposure after a radiological or nuclear incident and that provides a platform for future development of medical countermeasures. A partial-body irradiation (PBI) model using 137Cs gamma rays with hind limb (tibia) shielding was developed and assessed for the sequalae of radiation injuries to gastrointestinal tract, bone marrow (BM) and lung and among different genetic mouse strains (C57BL/6J, C57L/J, CBA/J and FVB/NJ). In this case, a marginal level of BM shielding (∼2%) provided adequate protection against lethality from infection and hemorrhage and enabled escalation of radiation doses with evaluation of both acute and delayed radiation syndromes. A steep radiation dose-dependent body weight loss was observed over the first 5 days attributed to enteritis with C57BL/6J mice appearing to be the most sensitive strain. Peripheral blood cell analysis revealed significant depression and recovery of leukocytes and platelets over the first month after PBI and were comparable among the four different mouse strains. Latent pulmonary injury was observed on micro-CT imaging at 4 months in C57L/J mice and confirmed histologically as severe pneumonitis that was lethal at 12 Gy. The lethality and radiological densitometry (HUs) dose responses were comparable to previous studies on C57L/J mice after total-body irradiation (TBI) and BM transplant rescue as well as after localized whole-thorax irradiation (WTI). Indeed, the lethal radiation doses and latency appeared similar for pneumonitis appearing in rhesus macaques after WTI or PBI as well as predicted for patients given systemic radiotherapy. In contrast, PBI treatment of C57BL/6 mice at a higher dose of 14 Gy had far longer survival times and developed extreme and debilitating pIeural effusions; an anomaly as similarly reported in previous thorax irradiation studies on this mouse strain. In summary, a radiation exposure model that delivers PBI to unanesthetized mice in a device that provides consistent shielding of the hind limb BM was developed for 137Cs gamma rays with physical characteristics and relevance to relatively high photon energies expected from the detonation of a nuclear device or accidental release of ionizing radiation. Standard strains such as C57BL/6J mice may be used reliably for early GI or hematological radiation syndromes while the C57L/J mouse strain stands out as the most appropriate for evaluating the delayed pulmonary effects of acute radiation exposure and recapitulating this disease in humans.

Optimization of personnel evacuation routes for sudden nuclear accidents based on hybrid genetic-grey wolf optimizer algorithm

To address the emergency situation resulting from a sudden nuclear accident, it is imperative to develop an optimal emergency response plan that ensures the prompt and safe evacuation of affected individuals from the hazardous area.The paper proposed the hybrid genetic-grey wolf optimizer algorithm (GA-GWO).This algorithm integrated radiation environment and road network to plan evacuation paths that minimizes the radiation dose. This algorithm enhanced the convergence and search capabilities of the genetic algorithm (GA) by incorporating wolf pack characteristics and internal competitive behavior. This improvement allowed for more efficient exploration of potential evacuation routes. The feasibility of GA-GWO was validated through a visualization simulation utilizing Web Geographic Information Systems (WebGIS). The findings indicated that GA-GWO generated evacuation paths that minimize radiation dose, providing safe routes for the affected population. This approach demonstrates significant potential for application in emergency response planning for sudden nuclear accidents, ensuring both prompt and safe evacuations.

Mapping Tokyo Olympics 3.0: archaeologies of the future

ABSTRACT Mapping Tokyo Olympics 3.0 is a collaborative sensory archive of demolition and displacement surrounding the three Tokyo Olympics. Understanding the Olympics as a cyclical `practice of subtraction,' where the city is not only rebuilt but unbuilt, we uncover the intertwined layers of the urban development history of these Games and the imperial (1940), high-growth (1964) and post-growth (2020/2021) periods in which they have occurred. Cancelled due to World War II, the first Tokyo Olympics were a phantom event; the second was held in the wake of massive protests against the US-Japan Security Treaty; and the third was postponed and hobbled by the global pandemic amid lingering fears caused by the Fukushima nuclear disaster. Each iteration of the Games has imposed physical effects on the urban landscape of Tokyo with the displacement of vulnerable and precarious persons as a consequence. Mapping the politics of demolition and displacement with the tools of hybrid spatial-sensory ethnography and using intermedial approaches, Mapping Tokyo Olympics 3.0 is a sensory archive of the lived experience of those displacements. Incorporating local knowledge and collaborative research-creation methodologies, we uncover layers of time, history and materiality to embrace contingencies and envision social futures. The sensory mapping archive becomes an archaeology of the future.

Piceatannol reduces radiation-induced DNA double-strand breaks by suppressing superoxide production and enhancing ATM-dependent repair efficiency

In contemporary society, humans are susceptible to various radiation-borne hazards, including exposure to therapeutic modalities using low-linear energy transfer (low-LET) radiations (X-rays and γ-rays), natural high-LET radiation sourced from cosmic rays, as well as nuclear accidents such as the Fukushima Daiichi Nuclear Power Plant incident. Therefore, this threat incites an imminent necessity to develop novel radioprotective agents against a wide range of LET radiation and elucidate the underlying molecular mechanisms. This study aimed at assessing the radioprotectivity of Piceatannol (PIC), a potent antioxidant polyphenol present in abundance in passion fruit, by investigating its effects on radiation-induced reactive oxygen species (ROS) production and the consequent DNA double-strand break (DSB) capacity and cellular senescence. Specifically, total ROS was evaluated by DCFDA staining, mitochondrial superoxide by MitoSOX staining, DSB by γ-H2AX immunostaining, and cellular senescence by Senescence-associated-β-galactosidase staining.The results demonstrated that PIC administration prior to exposure to both X-ray and high-LET radiation impeded radiation-induced DSB by suppressing ROS production. Interestingly, post-irradiation PIC treatment did not alter ROS levels but enhanced the efficiency of Ataxia Telangiectasia Mutated (ATM)-mediated DSB repair. Additionally, post-irradiation PIC treatment diminished senescence-associated beta-galactosidase levels, indicating that it hinders cellular senescence.Conclusively, PIC exerts radioprotective effects against a wide range of LET radiation. The study findings validate the potential application of PIC not only as a radical scavenger but also as a novel DSB repair-activating radioprotective agent.

Hydrothermal synthesis of melamine-based porous organic polymer for the advanced adsorption of iodine

The release of carbon dioxide into the atmosphere from the combustion of fossil fuels to produce energy contributes to severe climate change. Transitioning from fossil fuels to nuclear energy, which is free of carbon emissions, presents its own set of challenges, particularly the potential release of radioactive iodine in handling nuclear waste and in the instance of a nuclear accident. The ongoing research aimed to harness the advantages of porous organic polymers to capture iodine generated during nuclear fission by synthesizing them in an environmentally friendly and cost-effective hydrothermal process. Herein, a melamine-based porous organic polymer (MPOP-4), possessing reliable thermal and chemical stability, highly porous (SABET=195.48 m2/g), designed for iodine capture, is reported. The synthesis of MPOP-4 using melamine and uracil as basic building blocks showed high iodine vapor capture capacities in various media (6.30 g/g at 80 °C, 4833.15 mg/g from aqueous solution, and 1.98 g/g at 25 °C), accompanied by good regeneration ability. A significant abundance of nitrogen content, conjugated π-electron arrangement, and porous network make it an efficient iodine adsorbent. This study suggests the green nature (metal-free) of MPOP-4 and its ability to adsorb iodine.

Recommendations for Protective Actions Based on Projected Public Health Risks Following a Postulated Nuclear Power Plant Accident

This study conducted a regional assessment of the environmental and health consequences due to the release of radionuclides, including the most harmful, such as Cs-137 and I-131, from a hypothetical reactor accident at the first Nuclear Power Plant (NPP), Akkuyu Nuclear Power Plant, in Turkiye under different meteorological conditions. Simulations of the atmospheric flow were done using a Gaussian-based probabilistic model. Based on the estimated air and land contamination, radiation doses and cancer risks to the population were calculated. The assessment results were then compared with the criteria for protective actions in the event of a radioactive release and were subsequently used to assess the sufficiency of the Precautionary Action Zone (PAZ) and Urgent Protective Zone (UPZ) provided by regulations. The assessment indicated that evacuation outside the UPZ would likely be required during the early phase of the emergency, while sheltering indoors might be necessary up to 80 km. Protective actions such as restrictions on being outdoors or iodine prophylaxis are needed far beyond the radius of the UPZ. These results provide important insights into safe protective measures to reduce the risk of radiation-related cancer when considering a hypothetical severe nuclear accident. In addition, the results of this study aim to improve the current nuclear emergency response program and support nuclear decision-making.

Impacts of vertical variations in soil properties on H*(10) simulations for 137Cs deposition

Photon transport simulations based on the Monte Carlo method have played a crucial role in assessing and estimating the ambient dose equivalent rates H*(10), resulting from the deposition of 137Cs in soil following the nuclear power plant accident in Fukushima. However, a comprehensive examination of the effect of vertical variations in soil properties on the simulation outcomes has not yet been performed. Disregarding the vertical distribution of soil properties not only leads to potential inaccuracies in the shielding responses of soil layers but also in the determination of the radioactive source inventory, particularly when using the concentration data in Bq/kg. These oversights diminish the reliability of the simulation results. This study addresses several soil property factors that could potentially influence the simulation results, including variations in chemical composition induced by water content, bulk density profile, and estimated inventory profile, all evaluated through an examined simulation model. The results show that inappropriate assignment of the soil density profile can cause considerable errors in the H*(10) simulation outcomes. Furthermore, the sensitivity of H*(10) to variations in soil vertical density is analyzed, with the results indicating that H*(10) can be highly sensitive to changes in the bulk density of the top 0–5 cm soil layers. These results should facilitate the establishment of appropriate simulation strategies and support the reassessment of past simulation results.

Mitigating the Effects of 1-Palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol on Gastrointestinal Acute Radiation Syndrome after Total-Body Irradiation in Mice.

Total-body irradiation (TBI) with gamma rays can damage organisms in various unexpected ways and trigger several organ dysfunction syndromes, such as acute radiation syndrome (ARS). Hematopoietic cells and enterocytes are particularly sensitive to radiation due to their self-renewal ability and rapid division, which leads to hematopoietic ARS (H-ARS) and gastrointestinal ARS (GI-ARS). We previously showed that a lipid-based small molecule, 1-palmitoyl-2-linoleoyl-3-acetyl-rac-glycerol (PLAG), improved 30-day survival and alleviated H-ARS symptoms in BALB/c mice after a lethal dose (LD70/30) of gamma-ray TBI. In this study, we investigated the mitigating effects of PLAG on radiation-induced GI damage that occurs under the same conditions as H-ARS in BALB/c mice. Our study showed that PLAG facilitated the structural restoration of intestinal tissues by increasing villus height, crypt depth, crypt number, mucin-producing goblet cells, and proliferating cell nuclear antigen (PCNA)-positive crypt cells. PLAG significantly improved intestinal absorptive capacity and reduced intestinal injury-induced bacterial translocation. In addition, PLAG effectively inhibited radiation-induced necroptosis signaling activation in the intestinal crypt cells, which was responsible for sustained tissue damage and the release of high mobility group box 1 (HMGB1), a typical damage-associated molecular pattern. Overall, our findings support the radiation-mitigating potential of PLAG against GI-ARS after accidental radiation exposure.

Impact of the Great East Japan Earthquake followed by the nuclear power plant accident on the nursing students’ academic progress in Soma, Fukushima, Japan: a retrospective cohort study with questionnaire survey

BackgroundThe Great East Japan Earthquake and the subsequent Fukushima nuclear power plant accident in 2011 posed significant challenges to the educational sector, particularly affecting nursing students in the disaster area. However, to the best of our knowledge, there are no reports on the effects of the natural disaster coupled with the nuclear accident on the nursing students. Therefore, this study aimed to determine the impact of the Fukushima disasters on rate of academic failure events in nursing education.MethodsA retrospective cohort approach was conducted, focusing on 677 students from Soma Nursing School admitted between 2001 and 2017. Four failure events—failure to pass the national examination, student retention, suspension, and withdrawal from school—were compared between three time periods: pre-disaster, early peri-disaster, and later peri-disaster. This analysis was followed by a questionnaire survey among the students and an interview with faculty members to gain further insights.ResultsOf the student cohort, 17% had at least one failure event. Students in the later peri-disaster phase faced an elevated failure rate at 29%. Variables such as being male, admission during later peri-disaster period, and local pre-admission residence played a significant role in these failure events in multivariate logistic regression analysis (adjusted odds ratio [95% confidence interval, p value]; 2.63 [1.49–4.64, < 0.001], 3.207 [2.00–5.15, < 0.001], and 1.84 [1.12–3.02, 0.02], respectively).ConclusionsThis study highlights the impact of the Great East Japan Earthquake and the following nuclear accident on nursing education. The elevated failure rates in the later peri-disaster period emphasize the challenges posed by continuing disaster phases. Thus, there is a need for intensified and tailored strategies in nursing education in disaster-affected regions.

Effects of Continuous Prenatal Low Dose Rate Irradiation on Neurobehavior, Hippocampal Cellularity, Messenger RNA and MicroRNA Expression on B6C3F1 Mice.

Epidemiological, experimental, and ecological data have indicated the controversial effect of in utero chronic low dose rate (<6 mGy/h) with accumulative low (≤100 mGy) or high (>100 mGy) dose radiation exposure. Our main goal of this study was to examine if different low dose rates of chronic pre- and/or post-natal radiation exposure with accumulative high doses could induce hippocampal cellular, mRNA, and miRNA changes leading to neuropsychiatric disorders. The comprehensive mouse phenotypic traits, organ weight, pathological, and blood mRNA and miRNA changes were also studied. Using different approaches including SmithKline, Harwell, Imperial College, Royal Hospital, Phenotype Assessment (SHIRPA), neurobehavioral tests, pathological examination, immunohistochemistry, mRNA and miRNA sequencing, and real-time quantitative polymerase chain reaction (qRT-PCR) validation, we found that in prenatally irradiated (100 mGy/d for 18 days with an accumulative dose of 1.8 Gy) 1-year-old mice, no cellular changes, including immature neurons in the subgranular zone, mature neurons and glial cells in the hilus of the dentate gyrus and development of cognitive impairment, neuropsychiatric disorders, occurred. However, a significant reduction in body weight and mass index (BMI) was indicated by the SHIRPA test. A reduced exploratory behavior was shown by an open field test. Organ weights showed significant reductions in the testes, kidneys, heart, liver and epididymides with no abnormal pathology. mRNA and miRNA sequencing and qRT-PCR validation revealed the upregulation of Rubcnl and Abhd14b, and downregulation of Hspa1b, P4ha1, and Banp genes in both the hippocampus and blood of mice prenatally irradiated with 100 mGy/d. Meanwhile, downregulation of miR-448-3p and miR1298-5p in the hippocampus, miR-320-3p, miR-423-5p, miR-486b-5p, miR-486b-3p, miR-423-3p, miR-652-3p, miR-324-3p, miR-181b-5p, miR-let-7b, and miR-6904-5p in the blood was induced. The target scan revealed that Rubcnl is one of the miR-181b-5p targets in the blood. We, therefore, concluded that prenatal chronic irradiation with a low dose rate of 100 mGy/d and accumulative dose of 1.8 Gy or below might not induce significant adverse health effects on the offspring. Further study of different low dose rate radiation exposures with accumulative high doses may provide threshold doses for authorities or regulators to set new radiation safety guidelines to replace those extrapolated from acute high dose/dose rate irradiation to reduce unnecessary emergency evacuation or spending once a nuclear accident or leakage occurs.

Unveiling the role of uranium in enhancing the transformation of antibiotic resistance genes

Transformation represents one of the most important pathways for the horizontal transfer of antibiotic resistance genes (ARGs), which enables competent bacteria to acquire extracellular ARGs from the surrounding environment. Both heavy metals and irradiation have been demonstrated to influence the bacterial transformation process. However, the impact of ubiquitously occurring radioactive heavy metals on the transformation of ARGs remains largely unknown. Here, we showed that a representative radioactive nuclide, uranium (U), at environmental concentrations (0.005–5 mg/L), improved the transformation frequency of resistant plasmid pUC19 into Escherichia coli by 0.10–0.85-fold in a concentration-dependent manner. The enhanced ARGs transformation ability under U stress was demonstrated to be associated with reactive oxygen species (ROS) overproduction, membrane damage, and up-regulation of genes related to DNA uptake and recombination. Membrane permeability and ROS production were the predominant direct and indirect factors affecting transformation ability, respectively. Our findings provide valuable insight into the underlying mechanisms of the impacts of U on the ARGs transformation process and highlight concerns about the exacerbated spread of ARGs in radioactive heavy metal-contaminated ecosystems, especially in areas with nuclear activity or accidents.

Development of failure mitigation technologies for improving resilience of nuclear structures

After the Fukushima daiichi nuclear power plant accident, various countermeasures were taken for Beyond Design Basis Events (BDBE) in the system safety field. These included portable devices, additional backup facilities and accident management. They are different from approaches for Design Basis Events (DBE). In the field of structural mechanics; however, efforts were focused on strengthening to prevent failures for both DBE and BDBE in the same way. This approach will lead to limitless requirements for strength and expensive plants.As a breakthrough approach in structural mechanics for BDBE, we propose failure mitigation methods through the application of passive safety structures, where preceding failures release loadings and mitigate subsequent failures. When preceding failure modes have small impacts on safety performance, such as small deformation and crack initiation, and subsequent ones are catastrophic modes such as collapse and break, the passive safety structure improves safety and resilience. This idea is the utilization of passive characteristics of structures without additional equipment and electric power, allowing for simple and reliable plants.To demonstrate this idea, passive safety structures were applied to next-generation fast reactors, subject to high temperature and low-pressure conditions. In the case of loss-of-heat-removal accidents, high temperature conditions accelerate the creep deformation of structures. When deformation redistributes loadings and reduces stresses at important positions such as coolant boundaries, progression to creep rupture of boundaries can be mitigated. When an excessive earthquake occurs, plastic deformation and buckling become dominant, due to low pressure and, therefore, a thin-wall structure. The above-mentioned failure modes reduce rigidity and natural frequency. When the natural frequency becomes lower than the input frequency, vibration energy is hardly transferred to structures and the subsequent failures of structures, such as collapse and break, are mitigated.

Evaluation of radiation leakage in X-ray security inspection machine using a CZT spectrometer

Leakage radiation from X-ray security inspection machines is important, and measurement based on ionization chamber or scintillator detector is widely used. The leakage radiation is closely related to the size and the passing time of the luggage, the lead equivalent, the opening angle of the lead curtain, and the response time of the measuring instrument. To characterize the distribution of leakage radiation from the X-ray security inspection machine accurately, a small-volume CZT(CdZnTe) spectrometer was used to measure the energy spectra at a distance of 5 cm from the surface of the inspection machine. By designing and controlling the opening angle of the lead curtain according to the size of the luggage passing through the entrance and exit, the radiation dose was determined based on the measured energy spectra combined with the G(E)-function method. The results show that the maximum relative deviation between the air kerma rate and the ambient dose equivalent rate calculated by the G(E) function method with the standard dose rate does not exceed ±5%. The maximum relative deviation of the dose rate linear verification in the 137Cs radiation field is less than 2.5%. A calibrated CZT detector was utilized to measure the radiation leakage on the surface of the X-ray security inspection machine. It was discovered that the presence of the luggage items and the opening angle of the lead curtain will increase the leakage radiation dose on the surface of the security inspection machine system. This study provides a new approach for measuring scattered radiation of X-ray security inspection machines.

Strategic science performance and the illusion of consensus about Fukushima’s health effects

ABSTRACT After the 2011 Fukushima nuclear accident, one way that government authorities sought to quell public anxiety about the health impacts of radiation exposure was through the creation of the Fukushima Prefecture Health Management Survey (FHMS). Though the survey was intended to document the absence of harm, it instead made visible abnormally high rates of childhood thyroid cancer in Fukushima Prefecture. Despite this, the official state narrative remained unchanged: these cases were not causally related to radiation exposure, and there was still no need to worry about biological health impacts. Academic researchers affiliated with the FHMS have cemented this narrative through the depoliticized and authoritative platform of English-medium scientific literature, strategically mobilizing FHMS data to demonstrate the absence of a causal relationship between the cancer cases and the nuclear accident – despite also contending that the FHMS was not designed to be a robust empirical study capable of determining causal relationships. Through strategic science performance (SSP), they utilize tools of formal scientific discourse and credibility in a way that forecloses dissent and obscures the largely incomplete status of the underlying science. SSP in this context has contributed to the reconstruction of scientific ignorance about post-disaster radiation health impacts, and has further enabled the institutionalization of this ignorance in state governance that denies public accountability for the health and well-being of populations exposed to radiation contamination after the Fukushima accident.

Preliminary Promising Findings for Manganese Chloride as a Novel Radiation Countermeasure Against Acute Radiation Syndrome.

Military members and first responders may, at moment's notice, be asked to assist in incidents that may result in radiation exposure such as Operation Tomadachi in which the U.S. Navy provided significant relief for the Fukushima Daiichi Nuclear Reactor accident in Japan after an earthquake and tsunami in 2011. We are also currently facing potential threats from nuclear power plants in the Ukraine should a power disruption to a nuclear plant interfere with cooling or other safety measures. Exposure to high doses of radiation results in acute radiation syndrome (ARS) characterized by symptoms arising from hematopoietic, gastrointestinal, and neurovascular injuries. Although there are mitigators FDA approved to treat ARS, there are currently no FDA-approved prophylactic medical interventions to help protect persons who may need to respond to radiation emergencies. There is strong evidence that manganese (Mn) has radiation protective efficacy as a promising prophylactic countermeasure. All animal procedures were approved by the Institutional Animal Care and Use Committee. Male and female B6D2F1J mice, 10 to 11 weeks old, were used for neurotoxicity studies and temporal effects of Mn. Four groups were evaluated: (1) vehicle injection, (2) dose of 4.5 mg/kg for 3 days, (3) dose of 13.5 mg/kg, and (4) sham. Irradiated mice were exposed to 9.5 Gy whole body Co60 γ-radiation. MRI was performed with a high dose of manganese chloride (MnCl2) (150 mg/kg) to assess the distribution of the MnCl2. The mice have promising survival curves (highest survival-13.5 mg/kg dose over 3 days of MnCl2 at 80% [87% female, 73% male] P = 0.0004). The complete blood count (CBC) results demonstrated a typical hematopoietic response in all of the irradiated groups, followed by mildly accelerated recovery by day 28 in the treated groups. No difference between groups was measured by Rota Rod, DigiGait, and Y-maze. Histologic evaluation of the bone marrow sections in the group given 13.5 mg/kg dose over 3 days had the best return to cellularity at 80%. MRI showed a systemic distribution of MnCl2. The preliminary data suggest that a dose of 13.5 mg/kg of MnCl2 given over 3 days prior to exposure of radiation may have a protective benefit while not exhibiting the neurobehavioral problems. A countermeasure that can prophylactically protect emergency personnel entering an area contaminated with high levels of radiation is needed, especially in light that nuclear accidents are a continued global threat. There is a need for a protective agent with easy long-term storage, easy to transport, easy to administer, and low cost. Histologic evaluation supports the promising effect of MnCl2 in protecting tissue, especially the bone marrow using the dose given over 3 days (4.5 mg/kg per day) of MnCl2. Initial experiments show that MnCl2 is a promising safe and effective prophylactic countermeasure against ARS. MRI data support the systemic distribution of MnCl2 which is needed in order to protect multiple tissues in the body. The pathology data in bone marrow and the brain support faster recovery from radiation exposure in the treated animals and decreased organ damage.

The effects of mortality salience on perceived risk and trust in the managing bodies of nuclear power: The moderating effect of nuclear power support

AbstractPublic concern regarding nuclear power has arisen due to accidents involving radiation leakages, natural disasters, terrorism, war and other incidents. That is, people's concerns regarding the use of nuclear power have grown as situations that threaten their survival have increased. This study uses terror management theory to examine how mortality salience affects people's risk perception and trust in the managing bodies of nuclear power. The results of Study 1 and Study 2 revealed that when the level of support for nuclear power is low, the effect of mortality salience increases trust in the managing bodies. Study 2's findings reveal mortality salience leads to decreased risk perception of nuclear power. In the case of risks that are managed by others and that are difficult to understand, such as nuclear power, people tend to place higher value on the managing bodies because they cannot handle the risk themselves. These results highlight the changes in people's perceptions of nuclear power managing bodies when they are conscious of death and provide important information on the nature of communication between citizens and experts regarding nuclear power.

Thyroid cancer incidence in cohorts exposed in childhood to 131I released during the Windscale nuclear reactor accident at Sellafield, England, in 1957.

A fire in one of the Windscale nuclear reactors at Sellafield (Cumbria, England) in October 1957 released 1,800 TBq of 131I (half-life, 8 days) to atmosphere. Measurements of 131I activity in thyroids of exposed children showed typical thyroid doses of tens of milligray, but with some exceeding 100 mGy. Radiation exposure in childhood is known to increase the risk of thyroid cancer. Consequently, an investigation was conducted into whether raised numbers of thyroid cancer cases occurred in those exposed to 131I as young children in Cumbria. A database of Cumbrian births from 1950 onwards allowed cohorts of 56,086 births during 1950-1958 and 137,444 births during 1959-1980 to be constructed, periods including children potentially exposed and unexposed, respectively, to 131I. Three areas of Cumbria with different 131I contamination levels were identified from monitoring data, and births assigned to these three areas for the two periods of birth. Members of these six sub-cohorts were linked to incident thyroid cancer cases in Great Britain during 1981-2020 using national cancer registration databases, providing thyroid cancer incidence rates. Incidence rate ratios (IRRs), with the lowest contamination area as a reference, were computed. No IRR differed discernibly from unity. For births during 1950-1958, the IRR for the combined highest and intermediate 131I contamination areas was 0.68 (95% confidence interval: 0.24, 1.56), and no case of thyroid cancer was found in the small cohort born in the highest contamination area. In conclusion, no increased risk of thyroid cancer in those exposed to 131I as young children in Cumbria in 1957 was detected. This study adds to the evidence on the long-term risk of thyroid cancer following childhood exposure to low and moderate levels of 131I, such as occurred following the Fukushima nuclear accident in 2011.