Radiation Disaster Research Articles

Optimization of Pinhole Collimator According to Magnification Imaging for Radiation Disaster Monitoring: Monte Carlo Simulation

Optimization of Pinhole Collimator According to Magnification Imaging for Radiation Disaster Monitoring: Monte Carlo Simulation

Development of radiation education in schools after the Fukushima Daiichi nuclear power plant accident ― a study from the perspectives of regionality, multidisciplinarity and continuity

This study was designed to examine how teachers in Fukushima Prefecture have shaped radiation education and gained consensus on radiation-related issues since the Fukushima Daiichi nuclear power plant accident. We interviewed teachers and external experts who have been conducting radiation education since the nuclear accident, ascertaining their focus in introducing and implementing radiation education and the lessons they have learned. We then qualitatively analyzed the results. There was no practical radiation course of study (Shido Yoryo) to follow immediately after the disaster, so teachers individually devised curricula according to the developmental stages of their students. Their aims were to (1) tailor lesson structure to the students’ anxieties and distress, (2) promote students’ activities through knowledge and linkage to their daily lives via radiation measurements and disaster site visits, and (3) enable the students to self-educate and to take informed decision. These objectives required the implementation of continuous, multidisciplinary radiation education to enable the students to understand the impacts of the nuclear accident and enhance the resilience of children growing up in Fukushima, allowing them to overpass the rumor and stigma and to adopt adequate protective measures to face the remaining radiation in their environment. As nearly 10 years has passed since the accident, radiation education at schools has reached a turning point. While social interest in radiation education is waning, it is hard to say that adequate radiation knowledge has taken root among students, and therefore it is necessary to consider how radiation education should be delivered in the future. Such curricula based on the experiences of Fukushima Prefecture should be shared internationally in preparation for potential future accidents.

Single-Dose Administration of Recombinant Human Thrombopoietin Mitigates Total Body Irradiation-Induced Hematopoietic System Injury in Mice and Nonhuman Primates

Recombinant human thrombopoietin (rhTPO) has been evaluated as a therapeutic intervention for radiation-induced myelosuppression. However, the immunogenicity induced by a repeated-dosing strategy raises concerns about the therapeutic use of rhTPO. In this study, single-dose administration of rhTPO was evaluated for efficacy in the hematopoietic response and survival effect on mice and nonhuman primates exposed to total body irradiation (TBI). Survival of lethally (9.0 Gy) irradiated C57BL/6J male mice was observed for 30 days after irradiation. Hematologic evaluations were performed on C57BL/6J male mice given a sublethal dose of radiation (6.5 Gy). Furthermore, in sublethally irradiated mice, we performed bone marrow (BM) histologic evaluation and evaluated BM-derived clonogenic activity. Next, the proportion and number of hematopoietic stem cells (HSCs) were analyzed. Competitive repopulation experiments were conducted to assess the multilineage engraftment of irradiated HSCs after BM transplantation. Flow cytometry was used to evaluate DNA damage, cell apoptosis, and cell cycle stage in HSCs after irradiation. Finally, we evaluated the efficacy of a single dose of rhTPO administered after 7 Gy TBI in male and female rhesus monkeys. A single administration of rhTPO 2 hours after irradiation significantly mitigated TBI-induced death in mice. rhTPO promoted multilineage hematopoietic recovery, increasing peripheral blood cell counts, BM cellularity, and BM colony-forming ability. rhTPO administration led to an accelerated recovery of BM HSC frequency and multilineage engraftment after transplantation. rhTPO treatment reduced radiation-induced DNA damage and apoptosis and promoted HSC proliferation after TBI. Notably, a single administration of rhTPO significantly promoted multilineage hematopoietic recovery and improved survival in nonhuman primates after TBI. These findings indicate that early intervention with a single administration of rhTPO may represent a promising and effective radiomitigative strategy for victims of radiation disasters.

Knowledge and risk perception of radiation for Japanese nursing students after the Fukushima Nuclear Power Plant disaster

BackgroundThe Japanese have had three experiences of radiation disasters: the atomic bombs dropped on Hiroshima and Nagasaki in 1945, and the 2011 Fukushima Nuclear Power Plant disaster. The former two experiences have been covered in compulsory education programs. In light of these incidents, a strong fear of radiation has pervaded people of several generations. In such a situation, the role of nurses is important. When nurses treat residents, their attitudes change depending on how they understand and feel about radiation. The foundations of these attitudes are formed through student education. Hence, it is necessary to explore nursing students' understanding and risk perception of radiation, and the nature of radiation education received. ObjectivesTo assess the levels of understanding and risk perception of nursing students regarding radiation. DesignCross-sectional survey. MethodsA questionnaire survey was administered to all students (74 first-year, 79 second-year, 65 third-year, and 69 fourth-year students) in the nursing department of a Japanese national university. The response rate was 84%. Respondents were asked to rate their level of understanding of 50 phrases chosen from two supplementary texts about radiation for elementary school students and for middle and high school students, prepared by the Japanese Ministry. Further, they were asked to rate their risk perception for 30 events, and to answer six questions about radiation. ResultsIt was found that knowledge about radiation among Japanese nursing students was poor, because sufficient radiation education had not been provided. Hence, they displayed a greater fear of X-rays as compared to American students and members of the League of Woman Voters. However, it was also found that an increase in understanding might decrease risk perception. ConclusionsIt was concluded that nursing students require adequate education about radiation, in order to reduce their fear of X-rays and to mitigate their risk perception.

Survey of awareness of radiation disasters among firefighters in a Japanese prefecture without nuclear power plants.

Japanese firefighting organisations are essentially run as village, town, or city units. The Great Hanshin Earthquake of 1995 led to the establishment of emergency support teams to ensure rapid action in response to disasters beyond the capacities of local fire departments. The 2011 Great East Japan Earthquake involved both a tsunami and a radiation disaster caused by a nuclear reactor meltdown, underscoring the need for responses in complex disasters. This study aimed to assess Nagasaki Prefecture firefighters' preparedness for, awareness of, and anxiety regarding radiation disaster response with the aim of elucidating the factors affecting individuals' decisions to accept or reject assignment to a radiation disaster response team. A questionnaire survey was carried out with 1,122 firefighters in three firefighting departments in Nagasaki Prefecture, which does not have nuclear power plants. In total, 920 questionnaires were returned, and the 784 that were valid were analysed. Among the participants, 39% replied that they would have no difficulty accepting assignment to a radiation disaster response team; most of them were under 30 years old and unmarried. This group also included significantly higher percentages of participants who were confident about radiation disaster response or, if anxious, believed things would turn out fine, as well as those who replied that they were able to use the necessary equipment. Furthermore, this group had significantly higher percentages of participants who replied that they would definitely participate in seminars and those who replied that their level of preparedness for radiation disasters was sufficient. The willingness to be assigned to a radiation disaster response team was linked to confidence about radiation disaster response and about handling materials and/or equipment. Therefore, it is considered that measures to increase firefighters' confidence regarding response to radiation disasters will be linked to more proactive measures if and when such disasters occur.

Two-miRNA-based finger-stick assay for estimation of absorbed ionizing radiation dose.

Nuclear radiation and radioactive fallouts resulting from a nuclear weapon detonation or reactor accidents could result in injuries affecting multiple sensitive organs, defined as acute radiation syndrome (ARS). Rapid and early estimation of injuries to sensitive organs using markers of radiation response is critical for identifying individuals who could potentially exhibit ARS; however, there are currently no biodosimetry assays approved for human use. We developed a sensitive microRNA (miRNA)-based blood test for radiation dose reconstruction with ±0.5 Gy resolution at critical dose range. Radiation dose-dependent changes in miR-150-5p in blood were internally normalized by a miRNA, miR-23a-3p, that was nonresponsive to radiation. miR-23a-3p was not highly expressed in blood cells but was abundant in circulation and was released primarily from the lung. Our assay showed the capability for dose estimation within hours to 1 week after exposure using a drop of blood from mice. We tested this biodosimetry assay for estimation of absorbed ionizing radiation dose in mice of varying ages and after exposure to both improvised nuclear device (IND)-spectrum neutrons and gamma rays. Leukemia specimens from patients exposed to fractionated radiation showed depletion of miR-150-5p in blood. We bridged the exposure of these patients to fractionated radiation by comparing responses after fractionated versus single acute exposure in mice. Although validation in nonhuman primates is needed, this proof-of-concept study suggests the potential utility of this assay in radiation disaster management and clinical applications.

Nuclear and radiation threats as resources for modeling the security community on the example of the Abkhaz political crisis

Nuclear and radiation threats as resources for modeling the security community on the example of the Abkhaz political crisis

Effectiveness of a Basic Education Program on RadiationRelated Health Concerns for Nurses of Public Health and School Health in Japan

Background: After the Japanese nuclear power plant disaster in 2011, many residents became concerned about health effects of radiation. We aimed to evaluate the effectiveness of a training program for public health and school health nurses to improve their skills and expertise for better support to residents and students. Methods: This was a quasi-experimental study using single-group and pre-post comparison in 2016 in Hiroshima, Kagoshima and Hyogo prefectures of Japan. The educational evaluation was conducted through each sub-item of Bloom’s attainment goals. The evaluation of effectiveness was surveyed among 61 participants before and immediately after the workshop, and at 1-week and 1-month later. The analysis compared initial scores obtained before the workshop with subsequent responses. Where a significant difference was observed among three-group or more in the Friedman test, the Wilcoxon signed-rank test was used for two-group comparisons across the time periods. The significance level was set at P<0.05. Results: Data of 54 participants were analyzed. The knowledge based on Bloom’s taxonomy was increased as the number of correct responses increased significantly after the workshop (P<0.001). Cognitive domain was significantly increased after 1-week and 1-month (P<0.001). Affective and psychomotor performances were also increased compared with prior. Participants increased vocabulary related to radiation and developed confidence in radiation disaster recovery measures. Conclusion: Each sub-item of the Bloom’s attainment (goal, cognitive, affective, psychomotor) has almost been reached and the effect was maintained even after 1-month. By learning concrete words, they could explain accurately. Participants improved their confidence after receiving the training to respond and clarify the radiation anxieties to the community people.

Pillars of Hospital Preparedness in Radiation Emergency Management.

Human beings have always suffered and have incurred irreparable damages from different disasters. The most logical way to deal with disaster is to be comprehensively prepared. In line with this, the readiness of hospitals in the vicinity of nuclear centers is of great importance, as this could lead to reduced injuries and damage. In this study, we aimed to develop a model by which hospitals could effectively react to nuclear incidents. This is a comparative study using library studies, including examining existing patterns, recommended policies and instructions of WHO and IEAE, and articles and documents of selected countries that have models for radiation disaster management. The primary developed model was discussed in expert panels and, ultimately, with some modifications, was finalized. The findings of the research indicated that the most important factors in the success of crisis management are skill in predicting a crisis and having a preparation plan for necessary measures at the time of an incident. Different countries have developed various approaches toward radiation incident management that are mostly focused on human resources, medical equipment, and physical space. The model plan developed here includes a two-part foundation with seven pillars. Intra- and intersectorial arrangements are considered as the foundation, and the pillars are physical structure, medical equipment, human resources, process and instructions, intra- and intrasectorial coordination, information systems, and organizational structure. Having an appropriate model for coping with radiation incidents is pivotal for hospitals active in areas with nuclear centers. Undoubtedly, existence of an effective and comprehensive model could reduce the consequences of radiation crises.

Chemical-Biological Terrorism and Its Impact on Children.

Children are potential victims of chemical or biological terrorism. In recent years, children have been victims of terrorist acts such as the chemical attacks (2017-2018) in Syria. Consequently, it is necessary to prepare for and respond to the needs of children after a chemical or biological attack. A broad range of public health initiatives have occurred since the terrorist attacks of September 11, 2001. However, in many cases, these initiatives have not ensured the protection of children. Since 2001, public health preparedness has broadened to an all-hazards approach, in which response plans for terrorism are blended with those for unintentional disasters or outbreaks (eg, natural events such as earthquakes or pandemic influenza or man-made catastrophes such as a hazardous-materials spill). In response to new principles and programs that have evolved over the last decade, this technical report supports the accompanying update of the American Academy of Pediatrics 2006 policy statement "Chemical-Biological Terrorism and its Impact on Children." The roles of the pediatrician and public health agencies continue to evolve, and only their coordinated readiness and response efforts will ensure that the medical and mental health needs of children will be met successfully. In this document, we will address chemical and biological incidents. Radiation disasters are addressed separately.

Depression with auto-aggressive manifestations in victims during a radiation disaster and fighting

Purpose. To increase the level of medical care for depression patients with autoaggressive manifestations (AM) in victims during a radiation disaster and fighting by developing new diagnostic and treatment programs. Material and methods. The object and methods of the study were 70 liquidators of the accident consequences at the Chernobyl nuclear power plant aged from 54 to 65 years old and 45 combatants of the Anti-terroristic operation (Joint forces operation) aged from 25 to 59 years old – comparison group, depression patients with AM, psychosomatic pathology were examined. For the main group and the comparisons group were used clinical and paraclinical methods, division into groups, according to diagnostic and treatment programs, therapy and follow-up from 2 months to 2 years. Results. The main group observed increasing depressive frequency disorders with AM in liquidators of the accident consequences at the Chernobyl nuclear power plant. The examination revealed asthenic – in 34 (48.6 %) patients, anxiety – in 13 (18.6 %), apathetic – in 8 (11.4 %), hypochondriac – in 7 (10 %), dysphoric – in 5 (7.1 %), obsessive-phobic – in 3 (4.3 %) variants of depression with AM. These particular disorders are characterized asthenic, anxiety and apathetic symptoms, progressive course, personality changes with organic and psychosomatic traits, cognitive deficit (р <0,05). In the comparison group, asthenic was found in 13 (28.3 %) patients, anxious in 11 (23.9 %), hypochondriac in 10 (21.7 %), dysphoric in 6 (13 %), and obsessive-phobic – in 3 (6.5 %) and apathetic variants – in 2 (4.4 %) depression with AM. After the participation in the Anti-terroristic operation (Joint forces operation) fighters exhibit depression with AM in combination with psychosomatic and personality traits, changes in the bioelectrical activity of the brain. These particular disorders are characterized asthenic, anxiety, hypochondriac symptoms, personality and psychosomatic traits (р <0,05). Conclusions. The proposed comprehensive treatment and diagnostic program will increase the level of medical care of the liquidators of the accident consequences at the Chernobyl nuclear power plant, combatants of the Anti-terroristic operation (Joint forces operation) and prevent the occurrence of suicide. Key words: depression, autoaggressive manifestations, diagnostics, treatment, prevention, combatants of the Anti-terroristic operation (Joint forces operation), liquidators of the consequences of the Chernobyl accident.

Pathophysiology and clinical symp toms of acute radiation syndrome

Introduction: The use of radiation sources in various areas of life generates the risk of accidents and radiation disasters. The increase in terrorist threats as well as the risk of an outbreak of new armed conflicts carries the risk of using radioactive materials by terrorist groups and the military. Exposure to high doses of radiation and absorbing above-threshold doses by victims may cause acute radiation syndrome (ARS), as well as some distant effects. Personnel of the State Emergency Medical System (EMS) will be the first professional medical team in the process of providing assistance to such victims. The effects of further medical treatment in the hospital will depend on EMS’s first response, radiological triage and initial interventions taken. The aim: To present pathophysiology and clinical symptoms of acute radiation syndrome in the context of the medical practice of the EMS. Material and methods: For the purpose of this publication, an analysis of literature on the subject of the mechanism of ionizing radiation and its effects on the human body was performed. The work is focused on the interpretation of research results and their presentation from the EMS’s perspective. Results: The publication presents the impact of ionizing radiation on the body, the mechanism of damage to cellular structures and its consequences for individual organs and systems. ARS’s clinical (hematopoietic, intestinal, cerebrovascular) syndromes were discussed in detail, paying attention to radiation doses, the sensitivity of individual systems and organs, the dynamics of individual phases, as well as the ability to recognize and assess the severity of their progression by EMS personnel. Conclusions: The knowledge of pathophysiology, and ARS’s symptoms and dynamics is important to respond correctly to radiation incidents. This knowledge allows for efficient organization and emergency management during rescue operations. The increase in the risk of radiation incidents and radiation disasters generates the need for appropriate preparation of emergency rescuers, in particular, of the medical personnel of the State Emergency Medical Services.

Biological dosimetry – modern opportunities and prospects for diagnosis of acute radiation damage

In case of large-scale radiation incidents, timely detection of overexposed persons and determination of the severity of radiation injuries will be of great importance. The main methods of diagnosing acute radiation injuries are the methods of physical and biological dosimetry. In practice, in case of radiation accidents, physical dosimetry may be unavailable due to the lack of individual dosimeters, lack of information about the duration of exposure, dose rate, distance to the source of ionizing radiation, etc. Under such conditions, biological dosimetry becomes a reliable source of data on people’s radiation. Currently, the clinical manifestations of radiation-induced syndromes available for detection are used for the initial diagnosis of acute radiation injury at the advanced stages of medical evacuation in the early period after radiation exposure. However, in the early periods after radiation exposure, the results of an objective study do not always allow us to establish the fact of overexposure. The most informative laboratory and instrumental methods for diagnosing radiation injury. With large radiation, most biological dosimetry methods will not be available for the initial sorting of those affected at the initial stages of medical evacuation. The use of methods of biological dosimetry is to a greater extent justified in the conditions of the hospital stage of providing medical care to those affected during the elimination of the medical and sanitary consequences of radiation accidents and disasters.

Factors relating to anxiety among medical teams dispatched to the Fukushima nuclear power plant disaster

At the time of the accident at Tokyo Electric Power Company's Fukushima Dai-ichi Nuclear Power Plant, medical teams and radiation experts were solicited from all over Japan by the Japanese government to go to Fukushima Prefecture. While several reports on the incident and its management have been published, there have been no reports on the causes of anxiety felt by the volunteers or problems foreseen by organizations that declined to send volunteers. To identify the factors contributing to the anxiety levels of the dispatched personnel and to understand the difficulties faced while dispatching volunteers to the affected area, two different questionnaires were sent out to the recruited volunteers and recruiting organizations. Among the professionals sent to Fukushima Prefecture, we found that previous knowledge of radiation emergency or disaster medicine was inversely proportional to their anxiety levels (p < 0.001). Factors giving rise to apprehension depended on the professional's occupation (p = 0.042). Possessing and sharing radiological information among team members helped alleviate anxiety once the professionals entered the hazardous area. It is thus desirable to establish systematic plans with guidelines for proactive education and training for each kind of professional and policies regarding the dispatch of volunteered professionals to alleviate anxiety levels prior to dispatch.

Radioprotective Effects of Zinc and Selenium on Mice Spermatogenesis.

Background: Spermatogenesis system is one of the most radiosensitive organs in the body. A usual therapeutic dose of radiation such as the conventional 2 Gy in each fraction of radiotherapy and lower doses seen in diagnostic radiology or a radiation disaster affect the process of spermatogenesis potently. Selenium and zinc are two important elements playing key roles in the development of sperms and also have radioprotective effects. Objective: In this study aims to evaluate the radioprotective effect of zinc and selenium against radiation-induced mice testis injury.Material and Methods: In this experimental study, 30 mice were divided equally into 6 groups, including control selenium treated, zinc treated, radiation, radiation + selenium, radiation + zinc. Treatments started from 2 days before irradiation with 2 Gy cobalt-60 gamma rays. After 37 days, all mice were killed for histopathological evaluations.Results: Results showed that exposure to radiation caused a potent effect on spermatogenesis system. Treatment with selenium reversed these radiation effects potently, while zinc had some limited protective effects. Zinc treatment itself caused a detrimental effect on epididymis and, in combination with radiation, it leads to more damage to seminiferous tubules.Conclusion: In contrast to previous studies that proposed zinc to protect spermatogenesis against various toxic agents, results of this study showed that although zinc may protect from some parameters, it potentiates radiation damage on seminiferous tubules and has a detrimental effect on the epididymis. By contrast, zinc and selenium could alleviate radiation-induced toxicity on the most of the evaluated parameters.

医学教育における危機管理の向上及び 米国の原子力災害対応をICS から考える

医学教育における危機管理の向上及び 米国の原子力災害対応をICS から考える

Healing Fukushima: Radiation hazards and disaster medicine in post-3.11 Japan.

What happens when expertise is forced to face disasters of unprecedented scales? How is knowledge produced in critical moments when every action and decision is a matter of life and death? And how are local social networks mobilized to cope with unforeseen crisis? This paper addresses these questions by examining the emergence of disaster medicine expertise in the aftermath of Fukushima nuclear disaster that struck Japan in 2011. Studies on Fukushima's impact have to date revolved around the suffering of Tōhoku citizens and the development of Japan's nuclear energy industry. Acknowledging the gravity of such work, this paper offers an alternative, but equally crucial angle on the disaster: that of the medical caregiving and public health system built in response to radiation hazards resulting from the triple meltdowns at Fukushima Daiichi nuclear power station. Through detailed interviews conducted with eight medical practitioners in Fukushima Prefecture, this paper analyses the significance and impact of Japan's most recent radiation disaster on its public health infrastructure. To describe the contingent nature of radiation disaster medicine developed in response to radiation risk in Fukushima, we draw on Jasanoff's characterization of scientific knowledge as 'serviceable truths' with regards to public policy and the law, suggesting that expertise in relation to disasters is usefully understood in analogous terms.

Fingernail dosimetry using electron spin resonance for radiation disaster response

This study investigates the use of electron spin resonance (ESR) signals from human fingernails for retrospective dosimetry as part of radiation disaster response, focusing on the variabilities of individual responses to radiation. Samples of fingernails were collected from 7 adult donors (Asian type) and irradiated to 35 Gy and 70 Gy of gamma-rays from a Cs-137 source at a dose rate of 0.857 Gy/min. All irradiated fingernails were measured for 39 days with an X-band ESR spectrometer and stored in darkness inside the vacuum desiccator (30% humidity, 20°C) in between measurements at all times. All samples were harvested using one specific nail cutter and given no other special treatments. It was observed that the measured radiation-induced signals faded on about 10-12% after 1 day of exposure. Though the signal intensities showed a significant difference among the donors, stronger linearities in the dose responses were observed in the samples of younger donors. From the results obtained in this study, it is expected that fingernails would be a useful tool for retrospective dosimetry in case of an unexpected radiological accident or medical treatment error associated with exposure in therapeutic dose range, as far as the individual-based calibration curves were available. Further investigations will be made to clarify the reason for the different responses by using the fingernail samples taken from a greater number of donors of different ages and lifestyles.

Chemical and Radiation Training for Public Health and Nursing Students: An Under-Utilized Disaster Response Demographic

Introduction:Public health (PH) and nursing students are an underutilized demographic in disaster response. Knowledge of the disaster response phase may enhance student understanding of preparedness, and provide response capabilities.Aim:A single four-hour simulation-based training session, with toxicologists as instructors, can effectively improve PH and nursing student knowledge and skills in chemical and radiation response, despite minimal prior experience.Methods:A convenience sample was used to test PH and nursing students in a response training program. An introductory lecture and simulation training reviewed: mass casualty care, triage, personal protective equipment, decontamination, and chemical and radiation exposure toxidromes. An examination was administered pre-training, and then post-training, to evaluate relevant training, knowledge, risk perception, and comfort in response capabilities to chemical and radiation incidents.Results:Forty-two students attended the course; 39 were included in the study. Seventy-two percent (n=28) of participants had no prior disaster training. Overall, there were significant differences between the pre-test and post-test scores for all students [95% CI: 5.4 (4.7-6.1); p&lt;0.0001, paired t-test]; maximum score 15/15. Comparing scores of nursing and PH students, despite statistical difference in pre-test scores (median, IQR: 9.0 (7.5-10±2.0); 7.0 (5.7-9.0) respectively; p=0.048, Mann Whitney U-test), there were no statistical differences in post-test scores (median, IQR: 14.0 (13.0-14.0); 13.0 (12.0-14.0), respectively, Mann Whitney U-test). All students recognized nerve agent toxidrome and performed SALT triage after the training (p &lt;0.0001, McNemar test). Subjectively, participant comfort level in responding to a chemical or radiological incident improved (p &lt;0.0001, McNemar test). Individual risk perception for chemical or radiological disasters did not improve after training.Discussion:Improvement of knowledge and comfort was demonstrated, irrespective of previous experience. Simulation-based training of chemical and radiation disaster preparedness, led by medical toxicologists, is an effective means of educating PH and nursing students, with minimal prior fluency.

P59 - Mission to Mars: Radiation Safety or Radiation Disaster? Space Transit and Mars Radiation Exposure Risks—The Shielding Effect of a Graphene Space Suit and a Storm Shelter During Space Travel

P59 - Mission to Mars: Radiation Safety or Radiation Disaster? Space Transit and Mars Radiation Exposure Risks—The Shielding Effect of a Graphene Space Suit and a Storm Shelter During Space Travel