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[en] This manual provides details of the IAEA assessment and prognosis process, including its technical basis. It is complemented by a dedicated website, which provides access to assessment and prognosis tools and procedures. These tools provide a detailed technical workflow that is populated based on information submitted by the Accident State during a nuclear or radiological incident or emergency. This manual also serves as a companion publication to the Operations Manual for Incident and Emergency Communication (EPR–IEComm 2019), which contains a full documentation of the communication procedures for Contact Points identified under the Convention on Early Notification of a Nuclear Accident and the Convention on Assistance in the Case of a Nuclear Accident or Radiological Emergency
[en] Usage of radioactive sources for various medical and industrial purposes is very popular globally. Despite various technical advances, radiation accidents do occur due to lack of adequate expertise and regulatory control. Vitamin E is known to have antioxidant properties capable of scavenging free radicals, which has a critical role in the repair of radiation injuries. Tocopherols and tocotrienols belong to Vitamin E family and thus are used as radiation mitigators for the cases of accidental overexposure to radiation. Materials and Methods: In the present report, two such patients were treated using α-, δ-tocotrienol 400 mg twice daily for 6 months. Dose received by them was calculated and estimated to be 40 Gy. Results: Both the patients showed significant symptomatic improvement over 6 months. Conclusion: As a result of the present case study, α-, δ-tocotrienol can be recommended as a cost-effective and well-tolerated treatment option. (author)
[en] Exposure under accident conditions and potential exposure are regulated by the following Ukrainian documents: • Radiation safety standards of Ukraine (NRBU-97); • Radiation safety standards of Ukraine, addition: Radiation protection from sources of potential exposure (NRBU-97/D-2000); • General safety regulations of nuclear power plants (ZPBU-2008).
[en] Off-site nuclear emergency preparedness and response plans have conventionally focused on sheltering, stable iodine prophylaxis, and evacuation of residents as the primary short-term protective actions. Among these, the effectiveness of administering stable iodine prophylaxis has been affirmed over the years, by its ability to reduce intake of radioiodine and minimize the incidence of thyroid cancer in the administered population. The hypothesis of this study was that an advance distribution of prophylaxis, also called predistribution, to households during the preparedness stage is justified. To validate this hypothesis, we carried out a systematic literature review of existing studies on this topic. We also used multi-attribute utility theory to select relevant literature as per the criteria specific to this study. A detailed qualitative analysis was carried out to find the evidence that either substantiated or disproved our hypothesis. We found that over the years, there has been a steady increase in the number of articles advocating a predistribution strategy, especially following nuclear accidents. The most commonly held views against predistribution were as follows: (i) it would lead to accidental ingestion or possible overdose, (ii) it would be misplaced and not serve its purpose at the time of emergency, and (iii) it would not be cost-effective to implement such a distribution. The most common arguments supporting the hypothesis were as follows: (i) it offered maximum effectiveness as it could be immediately administered upon declaration of emergency, (ii) it reduces risk to the first responders who may otherwise be involved in distribution, and (iii) it serves as a last mode of radiation protection when consumed immediately and all other protective actions fail. This study found overwhelming evidence in support of the hypothesis, and hence, we suggest that a predistribution strategy for prophylactics is justified on the grounds of effective and timely radiation protection. (author)
[en] Nuclear forensics is the process of comparing sample characteristics with existing information about the types of material the origin and methods of production of nuclear and other radioactive material or previous cases associated with similar material. Thus, nuclear forensics regarded as a new area of integrated science research that allows not only the identification of radioactive material (withdrawn from illicit trafficking or resulting from a nuclear accident), but also to trace the entire chain of related events - from source origin until to detection. Nuclear forensics is the examination of nuclear and other radioactive materials using analytical techniques to determine the origin and history of this material in the context of law enforcement investigations or the assessment of nuclear security vulnerabilities. In this activity, consolidation and assistance of all organizations that can be involved in nuclear forensics are necessary. Considering the scope of activities and responsibilities of the regulatory body, maintaining a register of all radioactive sources and nuclear materials, controlling the movement of such materials, authorizing activities related to their use, issuing export and import statements, as well as state supervision and control of activities and export-import operations are included in the responsibilities of the regulatory body. Thus the regulatory body makes an indispensable contribution for the purposes of nuclear forensics.
[en] The need to quantify the uptake of 131I in the thyroid of the exposed population or workers is one of the main concerns to take into account in case of nuclear or radiological emergencies. In such scenarios, due to the high volatility and rapid intake by inhalation of 131I, it is very important a rapid identification of the exposed individuals to know their level of internal contamination in order to establish action protocols and countermeasures. In vivo measurements of 131I in the thyroid by gamma spectrometry at Whole Body Counters (WBC) is the recommended technique, but it is difficult to manage in case of a large number of individuals potentially exposed. It is known that gamma cameras located in the nuclear medicine services are available at most hospitals and could be used as an alternative method in order to provide support in the emergency response. Thus, this work describes a methodology to calibrate this kind of equipment with anthropometric phantoms to carry out direct measurement of 131I in thyroid for the quantification of internal contamination of the exposed population. A Gamma Camera (GC) of a public hospital from Madrid, H.U. La Paz, was calibrated for such purpose taking into account that a realistic geometry (10 cm distance from GC to phantom) and a rapid screening (counting time of 300 s with collimators removed) of internally contaminated individuals is necessary at early stage response. The calibration factors obtained for 131I vary with thyroid size being in the range of 0.0459 to 0.0541 cps·Bq-1. The minimum detectable activity (MDA) also varies with the thyroid size of the phantoms being in the range of 67 Bq to 79 Bq. An estimation of minimum detectable effective dose for children (E(70)) and adults (E(50)) has been carried out, taking into account such MDA values. Results show that, assuming a scenario of acute inhalation of 131I by members of the public, this methodology allows estimating doses far below 1 mSv three days after the intake. Moreover, the validation of the methodology has been carried out by participating in an international intercomparison exercise for the in vivo measurement of 131I in thyroid to the exposed population in emergencies. (CATHYMARA project, EC-OPERRA 2016–2017)
[es]Una de las principales preocupaciones a tener en cuenta en caso de emergencias nucleares o radiológicas es la necesidad de cuantificar la incorporación de 131I en tiroides tanto a trabajadores expuestos como a individuos de la población. En dichos escenarios, debido a la alta volatilidad y rápida incorporación por inhalación del yodo, es muy importante una rápida identificación de las personas expuestas para conocer su nivel de contaminación interna con el fin de establecer protocolos de acción y contramedidas. La medida in vivo de 131I en tiroides mediante espectrometría gamma en contadores de radiactividad corporal (CRC) es la técnica recomendada en estos casos pero es difícil de gestionar en situaciones en las que hay un gran número de individuos potencialmente expuestos. Las gamma cámaras, ubicadas en los servicios de medicina nuclear, y que están disponibles en la mayoría de los hospitales de nuestro país, están basadas en dispositivos de detección similares a los utilizados en los CRC y podrían utilizarse como un método alternativo de medida (cribado) en emergencias. Este trabajo describe una metodología para calibrar este tipo de equipos con maniquíes antropométricos simuladores del cuello y la tiroides de niños y adultos. Se ha calibrado una gamma cámara (GC) del Hospital Universitario La Paz (Madrid) teniendo en cuenta que una geometría realista y tiempos cortos de medida son factores determinantes para tener una respuesta adecuada en la fase temprana de la emergencia. Los factores de calibración obtenidos para 131I varían con el tamaño de la tiroides en el rango de 0.0459 a 0.0541 cps · Bq-1. La actividad mínima detectable (AMD) también varía con el tamaño de la tiroides de los maniquíes en un rango de 67 a 79 Bq. Se ha realizado una estimación de la dosis efectiva mínima detectable para niños (E (70)) y adultos (E (50)), teniendo en cuenta dichos valores de AMD. Los resultados obtenidos muestran que, suponiendo un escenario de inhalación aguda de 131I por inhalación tres días después de la incorporación, se pueden estimar dosis muy por debajo de 1 mSv. La validación del método se ha llevado a cabo mediante la participación en un ejercicio de intercomparación para la medida de 131I en tiroides a la población expuesta en emergencias (EU OPERRA CATHYMARA project 2016-2017).
[en] The regulations of Belarus relevant to the potential exposure comprise: • Safety requirements to ensure that the activities relating to the construction, operation and decommissioning of facilities are conducted to achieve the highest standards of safety that can be reasonably achieved; • Risk criteria which address the risk of mortality and of cancer from nuclear installations; • Dose and risk constraints for planned exposure situations and reference levels for emergency and existing exposure situations; • Emergency preparedness and response planning to mitigate the consequences of nuclear accidents.
[en] Accelerating and enlarging the “contribution of atomic energy to peace, health and prosperity throughout the world” is a statutory objective of the IAEA. For ten years the Peaceful Uses Initiative (PUI) has contributed to this objective, proving to be effective in mobilizing extrabudgetary contributions toward peaceful applications of nuclear technology.
[en] Background: The largest radiological accident to occur in any urban area happened in Goiânia, Brazil, in 1987. Objective: To evaluate the association between breast cancer incidence and ionizing radiation levels. Design and setting: Ecological study among residents of the city of Goiânia, Brazil. Methods: The central region of Goiânia, with seven major sources of contamination from cesium-137, was defined as the study area. The addresses of women diagnosed with breast cancer were identified between 2001 and 2010. The data were geographically referenced and, using census data, the annual averages of crude incidence rates were estimated. The existence of clusters of new cases was ascertained by means of the Moran index. Correlations of radiometric measurements with the incidence were assessed using unconditional linear regression. Results: A total of 4,105 new cases were identified, of which 2,233 were in the study area, and of these, 1,286 (57.59%) were georeferenced. The gross rates of total and referenced cases were 102.91 and 71.86/100,000 women, respectively. These were close to the average for Brazilian state capitals, which is 79.37/100,000 women. The cluster analysis showed slight correlations in three small sets of census tracts, but these were far from the sources of contamination. The scatter plot of points and the R2 value close to zero indicated that there was no association between the variables. Conclusion: This study reinforces the hypothesis that the ionizing radiation levels to which women living in Goiânia are now exposed to are not associated with the onset of new cases of breast cancer. (author)
[en] In the event of a criticality accident, not only the maximal doses received by the victims must be determined but it is also crucial to evaluate the doses to the different organs. With a neutron component, morphology is a key parameter in the organ dose calculation. As the simulation tools can be time consuming to proceed, especially if morphology is taken into account, for all the victims, it may be very useful to have a database of conversion coefficients that allow to obtain the organ doses from the dose measured in the dosemeter for different kinds of morphology. In this paper, we present a study performed to evaluate such conversion coefficients using voxelized anthropomorphic phantoms. These coefficients take into account two crucial parameters having an impact on the dose at the organs: the orientation of the victim in the radiation field and the morphology, that is to say the body mass index of the different victim. (authors)