Chernobyl Accident Research Articles

The case study of acquiring the repository of archival documents (1989–1993) on Chernobyl disaster mitigation efforts in Kaluga Region

The authors discuss the findings of the study of documents of 1989-1993 issued by the executive authorities and preserved in the State Archive of Kaluga Region. The purpose of the study is building the electronic archive of the documents related to Chernobyl disaster mitigation efforts on the contaminated territories. The research method of data analysis was applied. As a result of the accomplished study, the document repository was established to preserve the most significant materials related to the recovery of radiation contaminated lands of Kaluga region. The documents for the conversion into electronic formats were selected by criteria of the relation to the actual mitigation efforts. The study findings may be applied to analyze administrative decisions on various stages of execution, in particular, to assess the impact of statement of controlled radiation contaminated areas and disruption of the existing economic set-up.

CDO-TCN-BiGRU: An Optimized Hybrid Deep Learning Model for Shared Bicycles Demand Forecasting

<div>Accurate prediction of the demand for shared bicycles is not only conducive to the operation of relevant enterprises, but also conducive to improving the image of the city, facilitating people’s travel, and solving the balance between supply and demand of bicycles in the region. To precisely predict the demand of shared bicycles, a model combining temporal convolution network (TCN) and bidirectional gating recurrent unit (BiGRU) model is proposed, and the Chernobyl disaster optimizer (CDO) is used to optimize its hyperparameters. It has the ability of TCN to extract sequence features and gated recurrent unit (GRU) to mine time series data and combine the characteristics of CDO with fast convergence and high global search ability, so as to reduce the influence of model hyperparameters. This article selects the shared bicycles travel data in Washington, analyzes its multi-characteristics, and trains it as the input characteristics of the model. In the experiments, we performed comparison study and ablation study. The results show that the prediction error of the proposed model is less than other comparative models. Therefore, CDO-TCN-BiGRU model has the characteristics of high prediction precision and good stability.</div>

Clinicopathological Findings of 220 Pediatric, Adolescent, and Young Adult Patients with Thyroid Cancer in Fukushima Medical University Hospital.

Background: Thyroid ultrasound examinations (TUEs), conducted as part of the Fukushima Health Management Survey (FHMS), were initiated to monitor the health status of residents after the Fukushima Daiichi Nuclear Power Plant accident owing to concerns regarding the increased incidence of thyroid cancer among children, as observed after the Chernobyl Nuclear Power Plant accident. This study reported the clinicopathological characteristics of patients with thyroid cancer diagnosed through the FHMS and treated at the Fukushima Medical University Hospital. Methods: Data regarding the clinicopathological characteristics of patients with thyroid cancer were collected and evaluated in this descriptive study. Results: Among the 263 patients diagnosed with thyroid cancer as of September 2021, 220 patients with cytologically diagnosed thyroid cancer were treated as referrals from the FHMS. The median (interquartile range) age at the time of diagnosis was 18.6 (16.2-20.3) years. The median maximum tumor diameter was 13.0 (10.4-18.0) mm. To reduce surgical invasiveness, 199 patients (90.1%) underwent unilateral lobectomy. Pathological findings were suggestive of papillary thyroid carcinomas (PTC) in 216 (98.2%) patients; among them, 205 patients had PTC of the classical type. In addition, 216 (98.2%) patients had stage I disease. Cancer cell extension in the sternothyroid muscle or perithyroidal soft tissues and microscopic lymphovascular invasion were observed in 112 (50.9%) and 123 (55.9%) patients, respectively. No differences were observed between the two age groups (<18.6 years and ≥18.6 years) in terms of the clinical or pathological characteristics of thyroid cancer: risk classification (p = 0.69) and American Thyroid Association pediatric risk level (p = 0.24). Compared with those from previous reports, few surgical complications were observed. Conclusions: Patients with thyroid cancer diagnosed with TUEs underwent safe and minimally invasive operations, and careful postoperative follow-up was provided. The pathological findings of the detected thyroid cancers indicated that the majority were classical papillary carcinomas, and approximately half of the patients had extrathyroidal or lymphovascular invasion. No differences were observed between the two age groups in terms of the clinical or pathological characteristics of thyroid cancer.

ПОДВИГ ПОЖАРНОГО, СПАСШЕГО МИЛЛИОНЫ ЧЕЛОВЕЧЕСКИХ ЖИЗНЕЙ

Information about the Hero of Russia firefighter Vladimir Mikhailovich Maksimchuk is given. His service in the Moscow fire department and the Main department of fire protection is considered Ministry of Internal Affairs of the USSR. The role of V.M. Maksimchuk in the liquidation of the Chernobyl accident is revealed.

Phytohormonal balance and differential gene expression in chronically irradiated Scots pine populations from the chernobyl affected zone.

The impact of chronic radiation exposure on phytohormone content and expression of phytohormone- and stress-related genes of Scots pine in the zone affected by the Chernobyl accident was studied. Needle samples were collected from three plots with contrasting levels of radioactive contamination in the Polesye State Radiation-Ecological Reserve, Republic of Belarus, and two reference plots in the Kozeluzhsky forest in June 2022. The experimental plots were located within the artificial plantations of Scots pine established in 1982, before the accident in 1986. The activity of radionuclides 137Cs, 90Sr, 241Am, 238Pu, and 239+240Pu in soil and needles ensured dose rates ranging from 3.3 to 87 mGy × year-1, while at the reference plots, the range was 0.7‒0.8 mGy × year-1. Concentrations of plant hormones, including indole-3-acetic acid (IAA), indole-3-butyric acid (IBA), zeatin, and abscisic acid (ABA) in needles were evaluated using high-performance liquid chromatography (HPLC). We demonstrate that chronic radiation exposure is a significant stress factor that affects both phytohormonal balance and the expression of some important phytohormone- and stress-related genes. We found a tendency toward decreased ABA and auxin concentrations in trees from plots contaminated with radionuclides. The ratio (IAA + IBA + zeatin)/ABA was drastically raised at the most contaminated plots Masany and Kulazhin, reflecting the functional rearrangements of cellular metabolism that ensure plant adaptation under chronic radiation exposure. Changes in gene expression indicated modulation of ABA and Ca2+ signalling pathways, decreased potential of zeatin biosynthesis, and activation of heat shock proteins biosynthesis.

Dynamics of 137Cs concentrations in cow milk in the districts of Bryansk region

The publication continues the series of research addressed to the dynamics of 137Cs concentrations in agricultural products after the Chernobyl accident. The purpose of the present paper was to analyze the data describing the changes of 137Cs concentrations in cow milk. The information on countermeasures in animal breeding is presented, the system of radiological monitoring of milk contamination is described. It is shown that the dynamics of 137Cs concentrations in milk was seriously affected by the implementation of agrotechnical and veterinary measures. Effective half-lives of 137Cs concentrations in milk in the first period after the accident (1987-1992) ranged from 1 to 2.0 years. In the subsequent period (1991-2015), the reduction of milk contamination slowed down and the half-lives ranged from 5 to 25 years depending on the scope of remediation works and 137Cs aging in the soil.

Опыт лечения пораженных при аварии на Чернобыльской АЭС в условиях специализированного стационара

Summary. The purpose of the study is to analyze and summarize the experience of treating those affected by a radiation accident at the Chernobyl nuclear power plant (Chernobyl nuclear power plant) in a specialized hospital. Materials and research methods. The research materials are documented experience in organizing treatment and treating those injured in the Chernobyl accident with acute radiation injury. Research methods – analytical method and method of generalization. The results of the study and their analysis. 129 patients were sent to a specialized hospital in Moscow in the first two days, 84 of which were diagnosed with acute radiation disease (OLB) II-IV Art. severity. As the main diagnostic criteria for the early diagnosis of patients used: the timing and severity of the primary general and local (leather) reaction, the severity of lymphopenia and neutrophilic leukocytosis and other criteria. The main directions of early treatment of the affected were: – prevention and treatment of infectious complications; – detoxification therapy; – correction of water-electrolyte metabolism, parenteral nutrition in connection with common burns, oropharyngeal syndrome, intestinal syndrome, etc.; – pre-transplantation: HLA-typification of patients, the selection of donors, the actual transplantation of bone marrow from the donors of relatives and cells of the embryonic human liver (in the absence of donors) affected with irreversible damage to the bone marrow; – replacing therapy with blood cells. Based on the results of the study, the following conclusions were made: – the complex of medical measures was highly effective; – there were practically no fatal outcomes due only to infection in patients with bone marrow, even severe and extremely severe, form of OLB, not complicated by burns, radial enteritis or acute secondary disease due to bone marrow transplantation; – none of the patients died from hemorrhagic syndrome, most had no signs of bleeding even with deep and prolonged thrombocytopenia (&gt; 2–4 weeks); – the successful treatment of those affected in the Chernobyl accident was prepared by many years of experience in the work of the Clinical Division of Radiation Medicine of the Institute of Biophysics of the USSR Ministry of Health – State Research Center – Burnasyan Federal Medical Biophysical Center of Federal Medical Biological Agency for the treatment of those affected in other radiation accidents.

Dose Reconstruction for Epidemiological Studies among Ukrainian Chernobyl Cleanup Workers.

The present paper provides an overview of the methods and summarizes the results of estimating radiation doses and their uncertainties for Ukrainian-American epidemiological studies among the Chernobyl (Chornobyl) cleanup workers. After the Chernobyl accident occurred on April 26, 1986, more than 300,000 Ukrainian cleanup workers took part between 1986 and 1990 in decontamination and recovery activities at the site of the Chernobyl Nuclear Power Plant. The U.S. National Cancer Institute in collaboration with the Ukrainian National Research Center for Radiation Medicine conducted several epidemiological studies in this population. An important part of these studies was the reconstruction of the study participants' radiation doses and the assessment of uncertainties in doses. A method called realistic analytical dose reconstruction with uncertainty estimation (RADRUE) was used to calculate the doses from external irradiation during cleanup missions, which was the main exposure pathway for most study participants. At the initial phase of the accident during the atmospheric releases of radioactivity from the destroyed reactor, the cleanup workers also received doses from inhalation of radionuclides. In addition, study participants received doses at their places of residence, especially those who lived in highly contaminated areas. The radiation doses estimated for 2,048 male cleanup workers included in the Ukrainian-American epidemiological studies varied widely: (i) bone-marrow doses from external irradiation in the case-control study of leukemia of 1,000 cleanup workers ranged from 3.7 × 10-5 mGy to 3.3 Gy (mean = 92 mGy); (ii) thyroid doses in the case-control study of thyroid cancer in 607 persons from all exposure pathways combined were from 0.15 mGy to 9.0 Gy (mean = 199 mGy); (iii) gonadal doses in 183 cleanup workers from all exposure pathways combined in the study of germline mutations in the offspring after parental irradiation (trio study) ranged from 0.58 mGy to 4.1 Gy (mean = 392 mGy); (iv) thyroid doses in the human factor uncertainties study among 47 persons were from 20 mGy to 2.1 Gy (mean = 295 mGy); and (v) lung doses in the study of germline genetic variants associated with host susceptibility to COVID-19 estimated for 211 cleanup workers were from 0.024 mGy to 2.5 Gy (mean = 249 mGy). Doses of female cleanup workers were much lower than those of male cleanup workers: the mean doses for female cleanup workers were 27 mGy for 34 women included in the trio study and 56 mGy for 48 women participated in the study of germline genetic variants associated with host susceptibility to COVID-19. Uncertainties in dose estimates included two components: (i) inherent uncertainties arising from the stochastic random variability of the parameters used in exposure assessment and from a lack of knowledge about the true values of the parameters; and (ii) human factor uncertainties due to poor memory recall resulting in incomplete, inaccurate, or missing responses during personal interviews with cleanup workers conducted long after exposure. This paper also discusses possible developments and improvements in the methods to assess the radiation doses and associated uncertainties for cleanup workers.

Смертность от болезней системы кровообращения среди ликвидаторов последствий аварии на Чернобыльской АЭС из числа работников предприятий атомной промышленности

Summary. The aim of the study was to evaluate the mortality from circulatory system diseases (CSD) and its dynamics in liquidators of the Chernobyl accident consequences, workers of nuclear industry enterprises. Materials and research methods. The information base of the study was the data contained in the Industry Register of persons exposed to radiation as a result of the Chernobyl NPP accident (ORCh) functioning since 1987 in FGBU GSC FMBC named after A.I. Burnazyan FMBA of Russia. The database (DB) of the ORCH contains information about 21356 liquidators of the Chernobyl accident consequences. The study covers the period from 1987 to 2021. 304023 persons/years were accumulated in the register for the observation period. The material was processed using the Excel statistical package, the growth rate was calculated when assessing the dynamics of mortality. The results of the study and their analysis. In the structure of CSD mortality (ICD10: I00-I99,9) in liquidators of Chernobyl accident consequences the first rank place is occupied by chronic ischaemic heart disease unspecified (CIHD) (ICD10: I25,9), the second rank place – cerebrovascular diseases (CVD) (ICD10: I67,9), the third rank place – Unspecified cardiomyopathy (ICD10: I42,9). The growth rate of CSD mortality during the observation period is mainly positive, the highest in liquidators of working age.

Сучасний радіологічний стан орних угідь Народицької об'єднаної територіальної громади

Current radiological conditions and the possibility of returning to economic use of radionuclide-contaminated agricultural lands of the Narodychi United Territorial Community of the Korosten District of the Zhytomyr Region were assessed. The lands had been withdrawn from use in accordance with the Law of Ukraine "On the Legal Regime of the Territory Exposed to Radioactive Contamination as a Result of the Chornobyl Disaster" (Law) and marked in the State Land Cadastre of Ukraine as "radioactively contaminated land". It is shown that in accordance with the requirements of the Law on soil contamination density with 137Cs, 90Sr, 238-240Pu the lands currently do not belong to the zone of unconditional (mandatory) resettlement and even the zone of guaranteed voluntary resettlement and have no legal grounds for restrictions on their use. Predictive assessment of contamination of crops with 137Cs and 90Sr growing on the considered fields was performed. The assessments show which from the fields can be used to produce without countermeasure products below the permissible levels.

Airborne Toxicity in Don DeLillo’s White Noise

Abstract In the wake of the COVID-19 pandemic, people across the world came to realize the significant relationship between air and human health. This pandemic, which changed the course of many lives, demonstrated how air serves as a transmitter of viruses. However, this quality of air is not new, with air acting as a significant tool in transmitting diseases, pollution, and even death. It is crucial to understand that airborne diseases include but are not limited to epidemics or pandemics such as the black death, influenza, or COVID-19. Since the Chernobyl disaster, it is perceived that the previously feared disasters were replaced by new and human-made hazards such as toxicity and radioactivity. Environmental disasters such as the Bhopal disaster, Donora Smog, and the Chernobyl disaster emphasize the impact of toxic chemicals on humans and more-than-human lives. These disasters show that toxic substances that threaten the lives of all living things imperceptibly seep into the soil, water, and air, causing harm to ecosystems, and entering into human and more-than-human bodies. Exposure to toxicity and radioactivity can happen in the blink of an eye, transmitted through the air we breathe. Don DeLillo’s novel White Noise presents a significant example of toxicity through its striking portrayal of an airborne toxic event. This event, the appearance of a cloud of the fictional chemical Nyodene D., presents an environmental crisis through which relationships between air and environments can be explored. Similar to the issues and reflections experienced after the emergence of the COVID-19 pandemic, the characters in White Noise experience chaos, uncertainty, and fear following the abrupt occurrence of an airborne toxic event.

Dose rate dependent genotoxic and metabolic effects predict onset of impaired development and mortality in Atlantic salmon (S. salar) embryos exposed to chronic gamma radiation

Release of radionuclides to the environment from either nuclear weapon and fuel cycles or from naturally occurring radionuclides (NORM) may cause long term contamination of aquatic ecosystems and chronic exposure of living organisms to ionizing radiation, which in turn could lead to adverse effects compromising the sustainability of populations. To address the effects of chronic ionizing radiation on the development of fish, Atlantic salmon embryos were exposed from fertilization until hatching (88 days, 550 day-degree) to dose rates from 1 to 30 mGy·h−1 gamma radiation (60Co). The lowest adopted dose rate was similar to the highest doses measured in some water bodies right after the Chernobyl accident (1 mGy·h−1), however, well above current environmentally realistic scenarios (20 μGy·h−1), or the threshold assumed for significant effects on fish population (40 μGy·h−1). Dose dependent effects were observed on survival, hatching, morbidity, DNA damage, antioxidant defenses, and metabolic status. Histopathological analysis showed dose rate dependent impairment of eye and brain tissues development and establishment of epidermal mucus cell layers accompanied by increased DNA damage at doses ≥1.3 Gy (dose rates ≥1 mGy·h−1).At ≥32.8 Gy (dose rates ≥20 mGy·h−1) deformities and developmental growth defects resulted in respective 46 and 95 % pre-hatch mortality. The 10 mGy·h−1 exposure (≥ 12 Gy total dose) caused significantly increased DNA damage, impaired eye development, and both premature and delayed hatching, while no deformities or effect on survival were observed. We observed a dose rate dependent reduction from dose rate ≥ 20 mGy·h−1 (≥ 27 Gy total dose) on antioxidant SOD, catalase and glutathione reductase enzyme activities. The reduction of antioxidant enzyme activities was in line with observed developmental delay and disturbance to time of hatching. Metabolomic profiles showed a clear shift at dose rates ≥10 mGy·h−1 (≥ 12 Gy total dose) in pathways related to oxidative stress, detoxification, DNA damage and repair. Due to gamma radiation exposure, a switch of central metabolism from glycolysis, citric acid cycle and lactate production towards pentose phosphate pathway indicated a rewiring mechanism for increased production of reductive equivalents to maintain redox homeostasis at the expense of energy output and thus embryonic development.

Chernobyl Disaster Optimizer-Based Optimal Integration of Hybrid Photovoltaic Systems and Network Reconfiguration for Reliable and Quality Power Supply to Nuclear Research Reactors

Chernobyl Disaster Optimizer-Based Optimal Integration of Hybrid Photovoltaic Systems and Network Reconfiguration for Reliable and Quality Power Supply to Nuclear Research Reactors

Optimisation of decision-making on risk management strategy for the hydromelioration systems in biosphere reserves

The field of nature conservation in Ukraine is currently experiencing a profound crisis. In light of the mounting risks to Ukraine’s ecosystems, it is of paramount importance that conservation planning incorporates risk management strategies. In the aftermath of the Chernobyl disaster, the management of water bodies in the Exclusion Zone assumed paramount importance, given that the rivers had become the primary conduit for the transportation of radioactive substances. It is therefore imperative to evaluate the risks and vulnerabilities of climate change on Ukraine’s most developed economic sectors, population, and natural ecosystems. This will facilitate comprehension of the prospective consequences of climate change, ascertain the extent of potential losses, and inform decision-making aimed at reducing or preventing such losses in a timely manner. One of the primary challenges facing specialists at the Chornobyl Radiation and Ecological Biosphere Reserve, in addition to other organisations and enterprises of the State Agency of Ukraine on Exclusion Zone Management and scientific institutions, is the assessment of the feasibility of hydromelioration systems. It is of the utmost importance that a scientifically sound methodological approach be employed in order to ensure the reliability and validity of the results obtained through the assessment of risks and vulnerabilities to climate change. In this context, the utilisation of adaptive methodologies is of paramount importance for the development of risk management strategies. One such methodology is the Methodology for Risk Analysis and Information Management for Strategic Ecosystems (MARISCO). This article considers the potential deployment of the MARISCO adaptive method as a universal methodology for the analysis of environmental issues, with a view to informing decision-making on risk management strategies in the Chornobyl Radiation and Ecological Biosphere Reserve.

Novel modified Chernobyl disaster optimizer for controlling DC motor

This article presents the modified Chernobyl disaster optimizer (CDO) method for DC motor control to find the optimal proportional integral derivative (PID) settings. DC motors are widely used machinery. DC motors are also simple to use. The detonation of the Chernobyl nuclear reactor core served as the inspiration for the idea and guiding principles of the CDO. CDO has limitations in the stability of exploration and exploitation areas. This research aims to obtain a new balance of exploration and exploitation. This study suggests incorporating the levy flight and chaotic algorithm (CA) techniques to enhance the CDO method. This study was conducted with the MATLAB/Simulink software. A comparative technique, which included the marine predator algorithm (MPA), golden jackal optimization (GJO), and CDO, was utilized to determine the performance of the MCDO method. According to the study’s findings, the MCDO method’s overshoot value outperformed all other approaches.

Comparative analysis of the dispersion modeling and dose projection results performed under BARCO international project

Radiological assessments on zones to take protective actions in case of a nuclear or radiological emergency involve a series of real-time forecasts of radiological impact on the public at various distances from the release point, using actual weather or forecast data, information on the source term or facility status, and primary radiation monitoring data. This practice is implemented during the operation of emergency centers around the world in order to promptly report the occurrence and possible consequences of radiological accidents in the country and abroad in the event of a possible transboundary impact. Since the Chornobyl disaster, a lot of emergency exercises, research programs and projects, in particular, benchmarking, have served as international platforms for improving modeling capacity in atmospheric dispersion. This activity is carried out both on the basis of past severe accidents with significant atmospheric releases and corresponding radiological consequences, and on the basis of specific conditional (hypothetical) events that are developed in accordance with the purpose of the study. The paper is focused on the comparison results performed under the international project “Benchmarking on Assessment of Radiological COnsequences” (BARCO) conducted in 2020–2021 between five technical support organisations – members of the European Technical Safety Organisations Network (ETSON). The work contains a short overview of relevant international activity conducted in the past, a description of the BARCO project and its objectives, a list of participants, project tasks, initial data (source term, meteorology, list of benchmarking quantities, approach to data exchange, codes used). The study presents some of comparative analysis results obtained via two techniques such as code-to-code analysis (CTCA) and matched-pair analysis (MPA). The results discussion concentrates on the overall recommendations for code users. Conclusions provide the main outputs of the project.

Dose response analysis of protracted absorbed organ dose and site-specific cancer incidence in Sweden after the Chernobyl accident

Dose response analysis of protracted absorbed organ dose and site-specific cancer incidence in Sweden after the Chernobyl accident

Educational Center of the Republican Scientific and Practical Center of Radiation Medicine and Human Ecology

The results of the work of the educational center based on the Republican Scientific and Practical Center for Radiation Medicine and Human Ecology, the lead organization for the provision of specialized medical care to the population affected by the Chernobyl disaster, are presented. It is noted that the institution has created opportunities and provided optimal conditions for the actual receipt of continuous medical education.

Automating execution of surveillance procedures for NPP main control rooms

ABSTRACT For the past 30 years, progress in the automation of control processes in the nuclear industry has been much slower compared to other industries. In the same timeframe, other complex industrial and/or high-risk processes (e.g., aviation) have been revolutionized by the exponential increase of technology capability in computing and information systems. The reason for the relatively slow trickling of technology advancements in the nuclear field is multi-faceted: i) resistance to change from a traditionally proven solution (partially due to very specific regulation requirements); ii) the cost to adopt Computerized Procedure Systems for existing NPPs, without having a quantified and proven safety benefit; iii) relatively low number of new NPPs being built following the Chernobyl and Fukushima disasters; iv) possible negative impact on the human factors aspect. After a short introduction to automation in another high-risk industry (aviation), this paper focuses on the practical approach required for automating Surveillance Procedures, and at the same time taking into consideration the human factors impact of this approach.

Radioactivity and food safety in Serbia: Chernobyl accident and 4 decades later

Radioactivity and food safety in Serbia: Chernobyl accident and 4 decades later