Highly weathered mineral soils have highest transfer risk of radiocaesium contamination after a nuclear accident: A global soil-plant study

Accidental release of radiocaesium (137Cs) from nuclear power plants may result in long-term contamination of environmental and food production systems. Assessment of food chain contamination with 137Cs relies on 137Cs soil-to-plant transfer data and models mainly available for regions affected by the Chornobyl and Fukushima accidents. Similar data and models are lacking for other regions. Such information is needed given the global expansion of nuclear energy. We collected 38 soils worldwide of contrasting parent materials and weathering stages. The soils were spiked with 137Cs and sown with ryegrass in greenhouse conditions. The 137Cs grass-soil concentration ratio varied four orders of magnitude among soils. It was highest in Ferralsols due to the low 137Cs interception potential of kaolinite clay and the low exchangeable potassium in these soils. Our results demonstrate, for the first time, the high plant uptake of 137Cs in tropical soils. The most recent 137Cs transfer model, mainly calibrated to temperate soils dominated by weathered micas, poorly predicts the underlying processes in tropical soils but, due to compensatory effect, still reasonably well predicts 137Cs bioavailability across all soils (R2 = 0.8 on a log-log scale).

Nuclear power plant biological complications on marine biota from a probabilistic accident - A case study

An accident at the Barakah Nuclear Power Plant (BNPP) would result in a significant radionuclide release into the semi-closed marine environment. In this research, the released radionuclide distribution pattern and dose rate in the Persian/Arabian (Gulf) were calculated using a combined hydrodynamic/radiobiological model. Simulations of the dispersion of artificial radionuclide concentrations were conducted using a HYSPLIT model. To assess prospective hazards in case of an incident, environmental risk from ionizing contaminants: assessment and management (ERICA) tools were used. Using the Fukushima nuclear power accident as a model, the scenario source term profile was developed. The volumetric concentrations levels of pollutants ranged between 1 × 104 mBq m-3 to 1 × 1010 mBq m-3 in the radius of 200 km after 48 h. Based on the dose rates of the various marine biotas, Polychaete worms, and Pelagic fish, they had the highest and lowest dose contribution.

HAZMAT Technician-level Emergency Response: A Mental Model Framework for Radiological Dispersal Device (RDD) Incidents

ABSTRACT

This research examines the cognitive frameworks used by HAZMAT technicians when responding to incidents involving Radiological Dispersal Devices (RDDs), which are conventional explosive devices with radioactive materials incorporated. The objective is to introduce the Expected Mental Model State (EMMS) as a comprehensive evaluation tool for assessing and enhancing the expertise and situational awareness of emergency responders dealing with radiation crises. Through a series of expert focus group sessions using the well-established qualitative methodology of grounded theory, an Expected Mental Model State (EMMS) was developed. The methodology used an influence diagram architecture to conceptually capture and codify key areas relevant to effective emergency response. The research identifies fourteen EMMS key conceptual domains, further elaborated into 301 subtopics, providing a multi-dimensional structure for the proposed mental model framework. Three pivotal notions of mental model emerged within the EMMS framework: Knowledge Topology, Envisioning (Belief), and Response and Operability. These notions were found to align with previous theories of mental models and are vital for understanding how HAZMAT technicians conceptualize and respond to RDD incidents. The study emphasizes the critical role of mental models in enhancing preparedness and effective response strategies during radiation emergencies. The EMMS framework offers a versatile methodology that can be adapted across various kinds of emergency responders and high-risk situations, including the broader Chemical, Biological, Radiological, and Nuclear (CBRN) spectrum. Using this EMMS framework to develop an EMMS Diagnostic Matrix can provide a roadmap for identifying areas for the development of specialized training modules that have the potential to significantly elevate both the quality and efficacy of responder training and preparation.

Evaluating Reception Center Models for Radiation Response Screening Capacity and Throughput Predictions

ABSTRACT

Introduction: The current fleet of nuclear reactors in the United States is mandated to provide evidence that surrounding jurisdictions can screen their populations should an incident occur. Capacity can be measured as throughput in reception centers used for screening. Due to the significant staffing and resources required to exercise screening capacity, most jurisdictions typically perform smaller exercises and use models to estimate their overall throughput. Objective: To evaluate the applicability and realism of current throughput models and practices. Methods: Throughput capacity for radiation screening is estimated with a mathematical model derived by the Federal Emergency Management Agency (FEMA). The Centers for Disease Control and Prevention developed a discrete event simulation model as a tool, SimPLER, to evaluate capacity and make throughput predictions. Model estimates will be compared and evaluated using timing data collected at a large-scale exercise. Results: The FEMA model estimated a throughput 41.2% higher than the actual radiation screening throughput, while the SimPLER model provided identical values. The FEMA and SimPLER models' predicted throughputs were 50% and 3.8%, respectively, higher than total exercise throughput. Applying each model to the throughput projections for a 12-hour shift, the FEMA model estimates ranged from 665 to 6,646 people and the SimPLER model yielded an estimated throughput of 1,809 people with a standard deviation of 74.6. Conclusion: Discrete event simulation models, such as SimPLER, may provide more realistic and accurate predictions of radiation screening and throughput capacity of reception centers than mathematical models such as the FEMA model.

Comparison of TL characteristics of natural quartz and zircon

The dosimetry of different minerals is carried out to investigate the dose received by the population in case of a nuclear accident. Retrospective dosimetry is a field where there is a continuous search to find new materials. Beach sand minerals, namely quartz and zircon, were exposed to beta and gamma radiation and studied separately. A comparison of the thermoluminescence (TL) output of different peaks of quartz for beta and gamma was studied. Comparison of quartz peaks with the TL output of zircon peaks was carried out. TL output for a constant dose of gamma is always higher compared to the TL output received due to beta.

Decorporation dilemma: Interplay of prussian blue and potassium iodide in radioactive contamination

The expansion of the nuclear industry has led to various radioactive effluents, originating from routine operations or catastrophic incidents such as those at Three Mile Island (USA), Chernobyl (Ukraine), and Fukushima (Japan). Research conducted after these events emphasizes Cesium-137 (137Cs) and iodine 131 (131I) as major contributors to harmful airborne dispersion and fallout. These isotopes infiltrate the human body via inhalation, ingestion, or wounds, posing significant health risks. Understanding contamination mechanisms and devising effective countermeasures are crucial in mitigating nuclear incident consequences. We propose that concurrent administration of Pru-Decorp™/Pru-Decorp-MG and potassium iodide (KI) could synergistically reduce the levels of 137Cs and block uptake of 131I, respectively, in nuclear incident scenarios. Pru-Decorp™ capsules contain insoluble ferric hexacyanoferrate(II) and are equivalent to USFDA-approved Radiogardase®-Cs, offering radiation exposure mitigation for Cs and Tl contamination. Pru-Decorp-MG capsules consist of insoluble PB and magnesium hydroxide, serving as a prophylactic measure to reduce the risk of internal Cs and Tl contamination for rescue responders. Pru-Decorp™/Pru-Decorp-MG binds Cs/Tl ions in the gastrointestinal tract, hindering absorption and promoting excretion, while KI saturates the thyroid gland with stable iodine, decreasing the uptake of radioactive iodine isotopes. Our hypothesis is supported by studies demonstrating the effectiveness of combination therapies, such as calcium alginate, iron(III) ferrocyanide, and KI, in decreasing the retention of radioisotopes in vital organs. To test this hypothesis, we propose a comprehensive research plan, including in vitro studies simulating gastrointestinal conditions, animal studies to evaluate the efficacy of both drugs simultaneously, and safety clinical trials comparing Pru-Decorp™/Pru-Decorp-MG alone, KI alone, and their combination. Expected outcomes include insights into the synergistic effects of Pru-Decorp™/Pru-Decorp-MG and KI, guiding the development of optimized treatment protocols for simultaneous administration during radioactive contamination incidents. This research aims to address significant critical gaps in nuclear incident preparedness by providing evidence-based recommendations for concurrent antidote use in scenarios involving multiple isotope contamination. Ultimately, this will enhance public health and safety during nuclear emergencies.

Indoor concentrations of radioactive aerosols from nuclear accidents

In previous studies, some of the important factors that affect the spread of radioactive aerosols into indoors were considered. The studies were based on a new CFD approach and provided good descriptions for the deposition of aerosol particles inside small spaces and the penetration of aerosols into buildings through wall cracks. In this article, an application of those studies is implemented, where all the graphical relations that are required to estimate the indoor concentrations of radioactive aerosols from nuclear accidents are provided. This includes the deposition velocities, deposition rate, and the penetration factor. Particular interest is in the Fukushima-Daiichi nuclear power plant accident that took place in Japan in 2011. The aerosols carrying the radioiodine iodine-131 and the radiocesium cesium-134 and cesium-137 are studied. Based on the model's assumptions, and assuming steady-state air concentrations, the radioactive aerosols' concentrations in indoor air are about 97% of the concentrations in outdoor air. The applications demonstrate the model to be convenient and practical.

Awareness and preparedness level of medical workers for radiation and nuclear emergency response

Radiological science and nuclear technology have made great strides in the twenty-first century, with wide-ranging applications in various fields, including energy, medicine, and industry. However, those developments have been accompanied by the inherent risks of exposure to nuclear radiation, which is a source of concern owing to its potentially adverse effects on human health and safety and which is of particular relevance to medical personnel who may be exposed to certain cancers associated with low-dose radiation in their working environment. While medical radiation workers have seen a decrease in their occupational exposure since the 1950s thanks to improved measures for radiation protection, a concerning lack of understanding and awareness persists among medical professionals regarding these potential hazards and the required safety precautions. This issue is further compounded by insufficient capabilities in emergency response. This highlights the urgent need to strengthen radiation safety education and training to ensure the well-being of medical staff who play a critical role in radiological and nuclear emergencies. This review examines the health hazards of nuclear radiation to healthcare workers and the awareness and willingness and education of healthcare workers on radiation protection, calling for improved training programs and emergency response skills to mitigate the risks of radiation exposure in the occupational environment, providing a catalyst for future enhancement of radiation safety protocols and fostering of a culture of safety in the medical community.

Rethinking the Role of Biodosimetry to Assess Risks for Acute Radiation Syndrome in Very Large Radiation Events: Reconsidering Legacy Concepts

The development of effective uses of biodosimetry in large-scale events has been hampered by residual, i.e., "legacy" thinking based on strategies that scale up from biodosimetry in small accidents. Consequently, there remain vestiges of unrealistic assumptions about the likely magnitude of victims in "large" radiation events and incomplete analyses of the logistics for making biodosimetry measurements/assessments in the field for primary triage. Elements remain from an unrealistic focus on developing methods to use biodosimetry in the initial stage of triage for a million or more victims. Based on recent events and concomitant increased awareness of the potential for large-scale events as well as increased sophistication in planning and experience in the development of biodosimetry, a more realistic assessment of the most effective roles of biodosimetry in large-scale events is urgently needed. We argue this leads to a conclusion that the most effective utilization of biodosimetry in very large events would occur in a second stage of triage, after initially winnowing the population by identifying those most in need of acute medical attention, based on calculations of geographic sites where significant exposures could have occurred. Understanding the potential roles and limitations of biodosimetry in large-scale events involving significant radiation exposure should lead to development of the most effective and useful biodosimetric techniques for each stage of triage for acute radiation syndrome injuries, i.e., based on more realistic assumptions about the underlying event and the logistics for carrying out biodosimetry for large populations.

Pediatric Medical Countermeasures: Antidotes and Cytokines for Radiological and Nuclear Incidents and Terrorism

The war in Ukraine raises concerns for potential hazards of radiological and nuclear incidents. Children are particularly vulnerable in these incidents and may need pharmaceutical countermeasures, including antidotes and cytokines. Searches found no published study comparing pediatric indications and dosing among standard references detailing pediatric medications for these incidents. This study addresses this gap by collecting, tabulating, and disseminating this information to healthcare professionals caring for children. Expert consensus chose the following references to compare their pediatric indications and dosing of medical countermeasures for radiation exposure and internal contamination with radioactive materials: Advanced Hazmat Life Support (AHLS) for Radiological Incidents and Terrorism, DailyMed, Internal Contamination Clinical Reference, Medical Aspects of Radiation Incidents, and Medical Management of Radiological Casualties, as well as Micromedex, POISINDEX, and Radiation Emergency Medical Management (REMM). This is the first study comparing pediatric indications and dosing for medical countermeasures among commonly used references for radiological and nuclear incidents.

The convergence approach may be critical to improving early situational awareness in hostile radioactive environments

This study explores the impact of a simulated radiological dispersal device (RDD) event in an urban area on young adults around 20 years old. The RDD releases radioactive Cs-137 (7.0E+3 Ci), a common industrial sterilization source. The study aims to demonstrate that combining computational codes and epidemiological models can produce valuable data to guide initial actions when confronting a hostile radioactive environment. The HotSpot Health Physics and RESRAD-RDD codes were used in the simulation to evaluate the event's initial phase. The codes were executed together, and the HotSpot output data was input into RESRAD-RDD. Based on simulated radiation dose levels, estimated doses were incorporated into radioepidemiological models proposed by the Committee on Biological Effects of Ionizing Radiation (BEIR V or VII report). Despite limitations, data transfer between the models revealed no discontinuities or antagonisms. Radiation doses were simulated under three exposure conditions and two atmospheric release modes (day or night), suggesting that atmospheric conditions, sex, and exposure routine can strongly influence the perception of radiation impacts. This combination of methods can increase situational awareness and help with decision-making and developing coping strategies.

Radiation and Chemical Program Research for Multi-Utility and Repurposed Countermeasures: A US Department of Health and Human Services Agencies Perspective

Although chemical and radiological agents cause toxicity through different mechanisms, the multiorgan injuries caused by these threats share similarities that convene on the level of basic biological responses. This publication will discuss these areas of convergence and explore "multi-utility" approaches that could be leveraged to address common injury mechanisms underlying actions of chemical and radiological agents in a threat-agnostic manner. In addition, we will provide an overview of the current state of radiological and chemical threat research, discuss the US Government's efforts toward medical preparedness, and identify potential areas for collaboration geared toward enhancing preparedness and response against radiological and chemical threats. We also will discuss previous regulatory experience to provide insight on how to navigate regulatory paths for US Food and Drug Administration (FDA) approval/licensure/clearance for products addressing chemical or radiological/nuclear threats. This publication follows a 2022 trans-agency meeting titled, "Overlapping Science in Radiation and Sulfur Mustard Exposures of Skin and Lung: Consideration of Models, Mechanisms, Organ Systems, and Medical Countermeasures," sponsored by the National Institute of Allergy and Infectious Diseases (NIAID), a part of the National Institutes of Health (NIH). Discussions from this meeting explored the overlapping nature of radiation and chemical injury and spurred increased interest in how preparedness for one threat leads to preparedness for the other. Herein, subject matter experts from the NIAID and the Biomedical Advanced Research and Development Authority (BARDA), a part of the Administration for Strategic Preparedness and Response (ASPR), summarize the knowledge gained from recently funded biomedical research, as well as insights from the 2022 meeting. These topics include identification of common areas for collaboration, potential use of biomarkers of injury to identify injuries caused by both hazards, and common and widely available treatments that could treat damage caused by radiological or chemical threats.

Radiation-Related Thyroid Cancer

Radiation is an environmental factor that elevates the risk of developing thyroid cancer. Actual and possible scenarios of exposures to external and internal radiation are multiple and diverse. This article reviews radiation doses to the thyroid and corresponding cancer risks due to planned, existing, and emergency exposure situations, and medical, public, and occupational categories of exposures. Any exposure scenario may deliver a range of doses to the thyroid, and the risk for cancer is addressed along with modifying factors. The consequences of the Chornobyl and Fukushima nuclear power plant accidents are described, summarizing the information on thyroid cancer epidemiology, treatment, and prognosis, clinicopathological characteristics, and genetic alterations. The Chornobyl thyroid cancers have evolved in time: becoming less aggressive and driver shifting from fusions to point mutations. A comparison of thyroid cancers from the 2 areas reveals numerous differences that cumulatively suggest the low probability of the radiogenic nature of thyroid cancers in Fukushima. In view of continuing usage of different sources of radiation in various settings, the possible ways of reducing thyroid cancer risk from exposures are considered. For external exposures, reasonable measures are generally in line with the As Low As Reasonably Achievable principle, while for internal irradiation from radioactive iodine, thyroid blocking with stable iodine may be recommended in addition to other measures in case of anticipated exposures from a nuclear reactor accident. Finally, the perspectives of studies of radiation effects on the thyroid are discussed from the epidemiological, basic science, and clinical points of view.

Resilience after a nuclear accident: readiness in using mobile phone applications to measure radiation and health indicators in various groups (SHAMISEN SINGS project)

An anonymous web-based survey was developed to check different aspects (SHAMISEN SINGS project): stakeholder awareness and perceptions of available mobile applications (apps) for measuring ionising radiation doses and health/well-being indicators; whether they would be ready to use them in the post-accidental recovery; and what are their preferred methodologies to acquire information etc. The results show that participation of the citizens would be most beneficial during post-accident recovery, providing individual measurements of external ionizing dose and health/well-being parameters, with possible follow-up. Also, participants indicated different preferences for sources to gain knowledge on ionising radiation and for the functions that an ideal app should have. The level of awareness and readiness to use apps to measure ionising radiation dose depended on two main aspects: individual differences (age & gender) and whether people were from countries affected by the previous major accidents. We concluded that stakeholders could have benefits from the data management plan: (1) it potentiates resilience at individual and community level; (2) citizens' measurements contribute to environmental monitoring and public health screening; (3) linkages between different types of data (environmental exposure, individual behavioural diaries, and measurements of health indicators) allow to perform more rigorous epidemiological studies.

STATUS OF THE CURRENT DOMESTIC REGULATORY BASE FOR ENSURING RADIATION SAFETY AND ANTI-RADIATION PROTECTION OF MILITARY PERSONNEL DURING THE PERIOD OF MARTIAL STATUS

Prerequisite. In the conditions of a full-scale invasion, the issue of radiation safety and anti-radiation protection in the Armed Forces of Ukraine (AFU) occupies a special place, since the aggressor country violated global geopolitical international decisions, occupied civilian nuclear facilities, in the process of their liberation servicemen mayhave to act in conditions of increased radiation risk, the possibility of using tactical nuclear weapons also is not excluded.

OBJECTIVE

to investigate the state of the current national regulatory framework for ensuring radiation safety and anti-radiation protection of military personnel during the period of martial law.

METHODS

bibliographic, analytical, historical, systematic approach.

RESULTS

The main normative document on the organization of radiation safety and anti-radiation protection of both personnel and the population in Ukraine, as well as military personnel, currently in everyday conditions and in case of radiation accidents since 1998 and until now, are the State Hygienic Standards «Radiation Safety Standards of Ukraine (NRBU-97)». But neither in this document, nor in the transition to NRBU-2021-P, the issue of exposure to such a category as military personnel during the performance of combat (special) tasks is considered. The system of monitoring the radiation situation in Ukraine, documents on the organization of medical support for military personnel, including the Guidelines on the Medical Support of the Armed Forces of Ukraine for a Special Period (2019)and the Guidelines on the Organization of Radiation Safety in the Armed Forces of Ukraine (2020), were analyzed.modules of radiation safety principles in the Armed Forces of Ukraine were proposed.

CONCLUSION

The unsolved problem of normalization of the radiation factor in the case of man-made and socio-political emergencies can create significant problems in the organization of anti-radiation protection of troops and the population in the case of the use of nuclear weapons or radiation accidents in a special period and requires anurgent solution. It is obvious that there is a need to develop regulatory documents regarding the response and planning of continuous activities to respond to potential nuclear and radiation threats during martial law, including relationships at all levels of the management vertical and methods of communication in the event of a threat.

LARCalc, a tool to estimate sex- and age-specific lifetime attributable risk in populations after nuclear power plant fallout

A tool called LARCalc, for calculating the radiological consequences of accidental large scale nuclear power plant releases based on estimates of 137Cs ground deposition, is presented. LARCalc is based on a previously developed models that has been further developed and packaged into an easy-to-use decision support tool for training of decision makers. The software visualises the radiological impact of accidental nuclear power plant releases and the effects of various protective measures. It is thus intended as a rapid alternative for planning protective measures in emergency preparedness management. The tool predicts projected cumulative effective dose, projected lifetime attributable cancer risk, and residual dose for some default accidental release scenarios. Furthermore, it can predict the residual dose and avertable cumulative lifetime attributable risk (LAR) resulting from various protective measures such as evacuation and decontamination. It can also be used to predict the avertable collective dose and the increase in cancer incidence within the specified population. This study presents the theoretical models and updates to the previous models, and examples of different nuclear fallout scenarios and subsequent protective actions to illustrate the potential use of LARCalc.

STATE INSTITUTION «NATIONAL RESEARCH CENTER FOR RADIATION MEDICINE OF THE NATIONAL ACADEMY OF MEDICAL SCIENCES OF UKRAINE» - RESEARCH ACTIVITIES AND SCIENTIFIC ADVANCE IN 2022

Research activities and scientific advance achieved in 2022 at the State Institution «National Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine» (NRCRM) concerning medical problems of the Chornobyl disaster, radiation medicine, radiobiology, radiation hygiene and epidemiology in collaboration with the WHO network of medical preparedness and assistance in radiation accidents are outlined in the annual report. The report presents the results of fundamental and applied research works of the study of radiation effects and health effects of the Chornobyl accident. The report also shows the results of scientificorganizational and health care work, staff training. The Scientific Council meeting of NAMS approved the NRCRM Annual Report.

COGNITIVE ASPECTS OF DEPRESSION IN VICTIMS OF RADIATION ACCIDENTS, THE COVID-19 PANDEMIC, AND WARS

The relevance of the work is due to the significant increase in depression with cognitive disorders (CD) worldwide, and in Ukraine in particular, in victims of emergencies situations (ES), and the importance, but insufficient development of clinical and psychopathological aspects of medical and psychological-psychiatric care for this contingent of people. Despite the modern achievements of psychiatry in the study of depression in ES, an important problem is CD, which worsen the quality of life of patients, increase the risk of relapse, progressive course, and suicidal behavior. In order to improve the level of psychological and psychiatric care for depressed patients with CD in post-stress disorders by radiation accidents, the COVID-19 pandemic, and wars, the study of domestic and foreign literature on these disorders, which have both common features and certain differences, was conducted.Conclusions. The study confirms the significant prevalence of depression with CD in victims of radiation accidents, the COVID-19 pandemic, and wars, the insufficient development of clinical and psychopathological aspects and theneed for further study of this problem, as well as the creation of state measures of psychological and psychiatric care for these patients.

Experiences from the ARGOS user group nuclear emergency exercise

The Accident Reporting and Guiding Operational System (ARGOS) is a decision support system used to assist in the Emergency Preparedness and Response (EPR) to nuclear and radiological incidents. The ARGOS user group has been formed that is made up of government agencies across many countries that have a role in EPR to nuclear and radiological incidents. In 2020, a desktop exercise was organised for the members of the ARGOS user group. The exercise involved two hypothetical accidents at different times on the same date, namely a radiological release from a floating nuclear power plant (NPP) off the Norwegian coast and from the Loviisa NPP in Finland. The objectives of the exercise were to train and increase knowledge of the ARGOS system, to perform a comparison of model outputs, and to compare the recommendations of protective actions. In the case of the floating NPP the source term was provided, while in the Loviisa NPP scenario the participants were required to provide their own source term based on a description of the accident. The results on radiological consequences based on dispersion modelling, protective actions, source terms and dispersion modelling settings were collected from participants. A comparison was made between each of these reported aspects. In general, it was found that there was general agreement between the results for the floating nuclear power plant scenario in the sense of plume direction and extent, while in the case of the Loviisa NPP scenario, there was much greater variation, with the difference in source term estimates between the participants being an influencing factor. The participants acknowledged that taking part in an exercise of this nature increased their knowledge and understanding about using decision support tools such as ARGOS in planning and responding to nuclear and radiological emergencies.

Long-term study (1987-2023) on the distribution of 137Cs in soil following the Chernobyl nuclear accident: a comparison of temporal migration measurements and compartment model predictions

After the Chernobyl accident, a designated area of ~1000 m2 within the University farm of Aristotle University of Thessaloniki in Northern Greece was utilized as a test ground for radioecological measurements. The profile of 137Cs in the soil was monitored from 1987 to 2023, with soil samples collected in 5-cm-thick slices (layers) down to a depth of 30 cm. The mean total deposition of 137Cs in the area, backdated to the time of the Chernobyl accident, was determined to be 18.6 ± 1.8 kBq m-2 based on four follow-up profile measurements of 137Cs in the soil for the years 2022 and 2023. It is noteworthy that this value is similar the total deposition at the site, which was independently measured to be about 20 kBq m-2 during the first year after the Chernobyl accident. The fractional contribution of each soil layer (e.g., 0-5 cm, 5-10 cm, 10-15 cm, etc.) to the total deposition of 137Cs (0-30 cm) is presented and analyzed. A compartment model was utilized to forecast the temporal evolution of fractional contributions of the different soil layers to the total deposition of 137Cs (0-30 cm). In this model, each soil layer is represented as a separate compartment. The model assumes that the transfer rates between adjacent compartments are equal. The agreement between the measured fractional contributions and the model predictions suggests that the compartment model with equal transfer rates can capture the broad patterns of 137Cs migration within the soil layers over the long period of 1987-2023. However, the use of a second compartment model with increasing transfer rates between consecutive soil layers did not align with the observed outcomes. This indicates that diffusion may not be the primary migration mechanism over the 36-y period covered by our study.

A comparison of different detection techniques for 137Cs measurements of cattle in vivo

Agricultural lands with farm animals (e.g. cattle) can be significantly affected by radioactive contamination following nuclear or radiation accidents. In order to optimise the techniques for measuring 137Cs in contaminated cattle, selected radiation detectors have been tested and calibrated using volumetric radiation sources. In addition, a mathematical phantom of a cow was created within Monte Carlo simulations. The main aim of the research was to propose a method for making rapid measurements of 137Cs in cattle in vivo/in situ and to select the most suitable measurement set-up. Measurements of contaminated cattle in vivo were carried out in Belarus with one selected detector, and were then compared with measurements of meat in a laboratory and with measurements of a control group of cows. The proposed measurement method was also tested on measurements of 137Cs in wild boars in Czechia with higher levels of the 137Cs activity.

Risk assessment for the optimization of the grid of a telemetric network monitoring system

The goal of this work was to develop a methodology for risk assessment in case of an accident originating from a nuclear power plant, and consequently, to improve the relevant radiation monitoring network. In specific, the study involved risk estimation in Greece from a transboundary nuclear power plant accident. The tool employed was JRODOS (Java-based Real-time Decision Support), which is a system for off-site emergency management of radioactive material in the environment. This tool, widely used to generate and study scenarios for nuclear accidents worldwide, provides valuable insight to facilitate emergency preparedness and response. The probability of the plume arriving at numerous regions within the country was calculated, along with the maximum dose rates in case of transport. A risk assessment was performed, and geographical regions were prioritized in terms of risk-based environmental radioactivity burden. A total of 29 administrative districts were identified as low to medium-risk regions. Acquired results were used to determine the optimal spatial distribution of detectors for upgrading the existing monitoring network of environmental radioactivity.

Effectiveness of simplified dose estimation equations for triage after criticality accident-a case study of dose assessment in the JCO criticality accident

The dosimetry for the triage of personnel encountering a criticality accident was investigated. The JCO criticality accident of 1999 was selected as a case study, and attention was paid to the identification and the segregation of severely exposed personnel. A series of Monte Carlo calculations revealed that simplified equations proposed by ANSI to estimate dose with respect to distance work well to determine the region of interest for triage.