Journal of Radiological Protection最新文献

The 16th International Congress of the International Radiation Protection Association (IRPA16), held in conjunction with the 69th Annual Meeting of the Health Physics Society (HPS) in Orlando, USA, provided an excellent platform for radiation protection professionals to exchange knowledge and advancements in radiological protection science and practice. The event featured 1241 participants from 67 countries, with 241 oral presentations and 440 posters spanning 11 thematic areas, including radiation health effects, dosimetry, medical applications, nuclear energy, and emergency preparedness. Key discussions covered updates on radiological protection systems, new findings in low-dose radiation epidemiology, and advancements in radiation measurement and dosimetry. Special focus was given to education and training, stakeholder engagement, and the integration of ethical considerations into radiological protection practices. The congress also highlighted emerging challenges in non-ionising radiation (NIR), medical radiation safety, and radioactive waste management. Notably, the prestigious Rolf M. Sievert Award was presented to Dr Maria del Rosario Perez for her significant contributions to global radiation protection, and the Gold Medal for Radiation Protection was awarded to Dr Ohtsura Niwa for his work in community engagement following the Fukushima accident. IRPA16 reinforced the importance of harmonising radiation protection standards globally and fostering interdisciplinary collaboration to address emerging scientific and societal challenges in radiological safety.

Ukraine continues to face problems of ensuring safety in the territories affected by hostilities, where many radiation-hazardous facilities are located and radioactive sources are used or stored. These include in particular, plant under decommissioning and other facilities at the site of the Chornobyl nuclear power plant, the sites of the national radioactive waste (RW) management operator, and other facilities linked to RW management inside and around the Chornobyl exclusion zone (CEZ). Regulating the safety of such facilities during wartime is an unprecedented task. Problematic issues are related to the temporary occupation by military forces, the aftermath of fighting such as unexploded shells and mines, and the continuing risk of shelling and missiles that pose threats to safety supervision. The radiation risks are linked to possible damage and theft of equipment, loss of control over RW packages, violations of the operating rules at the facilities, difficulties in delivering personnel to the facilities, and partial evacuation of personnel. At the same time, the situation is made complicated by continuing military risks and the loss of normal logistical capabilities. The regulator State Nuclear Regulatory Inspectorate of Ukraine, in collaboration with its technical support organisation, the State Scientific and Technical Center for Nuclear and Radiation Safety and with support from the Norwegian radiation and nuclear safety authority, has developed approaches and procedures for regulating the safety of facilities and activities within the CEZ during wartime, at the time of active armed conflict and addressing the aftermath following de-occupation. This approach was developed in the absence of global experience in regulating safety under such conditions and can be applied as further areas are de-occupied and hostilities cease. This article aims to share with the international community unique Ukrainian experience in maintaining safety principles and provisions in wartime conditions and handling licensing matters during the hostilities and after liberation of the occupied territories.

Recently, the International Commission on Radiological Protection (ICRP) has released adult and pediatric mesh-type reference computational phantoms (MRCPs) through its Publications 145 and 156, which incorporate anatomically refined respiratory tract structures that overcome the limitations of earlier voxel and stylized models. In this study, a comprehensive dataset of specific absorbed fractions (SAFs) and radionuclideSvalues was generated for the respiratory tract across the entire age- and sex-specific series of ICRP MRCPs. The phantoms were implemented in the Geant4 Monte Carlo radiation transport code (version 11.3) to compute SAFs for photons, electrons, and alpha particles over the energy ranges of 0.001-10 MeV for photons and electrons and 1-12 MeV for alpha particles, with certain low-energy values supplemented by a limiting SAF interpolation approach. The calculated SAFs were subsequently combined with nuclear decay data from ICRP Publication 107 to derive S values for all relevant source regions following inhalation exposures to radionuclides. Photon and electron SAFs were obtained for 36 source-target combinations, and alpha SAFs for 18 combinations, whileSvalues were produced for 1,252 radionuclides. The calculated SAFs exhibited clear age-dependent trends, with larger values in younger phantoms. Furthermore, the calculated SAFs andSvalues were generally greater than previously reported ICRP values. The complete dataset is available through an open-access repository, representing the first effort to provide SAFs andSvalues for the respiratory tract using the ICRP MRCPs. The calculations explicitly accounted for micrometre-scale source and target regions within anatomically realistic respiratory tract structures, while also incorporating inter-tissue irradiation cases, which had not been possible with previous models.

The current Russian aggression against Ukraine leads to complex needs for and challenges to the expansion of the Ukrainian radiation monitoring network. The issue of preparedness and response in times of war, in particular during the seizure of the Zaporizhzhia Nuclear Power plant site, has greatly exacerbated the issue of developing a response strategy based not only on expert opinion on possible scenarios but also on actual measurements in the first hours of a potential release. In this context, the shortage of radiation monitoring stations has become a significant issue for operators, the public, and various organisations, including State Nuclear Regulatory Inspectorate of Ukraine (SNRIU) and State Scientific and Technical Center for Nuclear and Radiation Safety. To address this, proposals have been made to identify suitable locations for additional automatic radiation monitoring systems to complement the existing ones. The main environment for solving this problem became the RESTORATION project, conducted in 2023-2024 in collaboration with Norwegian Radiation and Nuclear Safety Authority SNRIU, and State Scientific and Technical Center for Nuclear and Radiation Safety. The main objective of activities is to identify the data needed to select appropriate locations for radiation monitoring stations using the European decision support system JRODOS. For this study, the reference severe accident scenario at Ukrainian nuclear facilities was selected in accordance with the IAEA Emergency Preparedness Category I. Such an event may cause significant impacts beyond the boundary of the monitoring zone and enables the assessment of how actual meteorological conditions influence the atmospheric dispersion of radionuclides. Meteorological data from a five year period were used for statistical calculations. Preliminary monitoring quantities were based on the data requirements of the JRODOS decision support system, which provided the necessary statistical outputs. The paper highlights the role of the radiation monitoring network during an emergency as well as the problem of its potential development in view of the challenges with regard to civil protection, analysis of radiological situations, dispersion modelling, and dose projection. An overview of the existing networks and hierarchy of monitoring data providers among the Ukrainian organisations is presented. Based on the Ukrainian experience, in particular the results of the RESTORATION project, a methodological approach and recommendations for expansion of the radiation monitoring network are presented.

Dose estimation in response to internal radionuclide exposures requires reconstruction of the initial intake activity, which is frequently unknown due to the absence ofa prioridata. In such scenarios, intake is inferred from bioassay measurements obtained at one or more time points post-exposure. Reconstructing an initial intake from bioassay relies on biokinetic models that describe the body distribution and clearance of the toxicant. These models typically employ first-order differential equations with generalised population parameters, which do not capture individual variation in metabolism or anatomy. Thus, reconstruction of initial intakes is affected by multiple sources of stochasticity, including physical deposition of the inhaled radionuclide, detection system uncertainty, and inter-individual physiological variability. The capacity of machine learning (ML) algorithms to model highly non-linear and often stochastic processes makes them appropriate for augmenting intake reconstruction. This study applies artificial neural networks to estimate the initial intake activity of⁹⁰Sr inhaled by beagles. Model performance and sensitivity to input data quality were assessed through inclusion of individual-specific features, such as age, weight, and sex. Three data regimens were systematically designed, each with distinct pre-processing pipelines and model complexity. The first regimen demonstrates feasibility of intake reconstruction using bioassay measurements taken within 14 days post-exposure. The second regimen demonstrates that summary statistics of retention functions in historical records lack sufficient resolution for individualised ML modelling. The third regimen shows that historical dose estimates, despite limitations in resolution and methodology, can be used as surrogate features when multiple post-exposure time points are available. Root mean squared error was used to evaluate prediction error, while a custom metric, the variance relative difference, quantified model bias. In addition to evaluating predictive performance, this study assesses the integrity and usability of historical data from⁹⁰Sr beagle inhalation experiments conducted at the Inhalation Toxicology Research Institute between 1966 and 1987.

In March 2011, the Great East Japan Earthquake triggered the release of radionuclides from the Fukushima Daiichi Nuclear Power Plant. This event impacted residents in Fukushima prefecture and surrounding areas and caused significant public health concerns. This study aims to determine whether current reproductive intentions among Japanese parents are related to long-term perceptions of health risks from radiation. The analysis uses data from an online survey conducted in 2018 among 620 Japanese adults, 310 of whom were living in Fukushima prefecture at the time of the 2011 disaster. We investigated levels of confidence in giving birth and caring for a child by categorising survey respondents based on their current family structure and reproductive intentions. We also examined how radiation risk perception mediates the relationship between place of residence and confidence in giving birth or caring for a child. Among the four subgroups, those who neither had children nor intended to have children were most concerned about caring for a child, regardless of place of residence. Conversely, among those who had children and also had further reproductive intentions, those living in Fukushima at the time of the disaster reported the highest confidence in both giving birth and caring for a child. Additionally, we found that the association between place of residence and parental confidence in giving birth was mediated by perceived genetic health risk. This finding implies the need to tailor radiation risk-related information to address concerns about genetic health effects for couples preparing for parenthood in regions not directly impacted by the disaster in the long term.

The principle of as low as reasonably achievable (ALARA) is of paramount importance for the radiation protection of workers, and more specifically in the context of the decommissioning of nuclear facilities. For that purpose, several tools have been developed to measure and assess radiation doses to workers, to plan radiological work, and to ensure that safety protocols are followed. Most of these planning tools are based on the well-established point-kernel (PK) method, while others rely on Monte Carlo (MC) simulations. The scope of this paper is to compare, for some case studies, the performance and accuracy of VISIPLAN 4.0, a PK-based tool developed at SCK CEN, with MC simulations, to highlight the advantages and limitations of both methods. The major advantage of PK methods is usually related to their lower computational burden, at the cost of a less accurate assessment of dose values. However, depending on the number of source points chosen for the PK method, the simulation time could be comparable to MC simulations: in the scenarios presented in this paper, the simulation time was comparable to MC simulations when a high number of source points was considered. Moreover, VISIPLAN, on average, overestimated the dose assessment by approximately 50% compared to MC results.

Intra-operative radiographic imaging is indispensable in modern hand surgery but exposes surgeons' hands to significant ionising radiation. In theSHIELDmulticentre audit performed across all Irish Plastic Surgery units, non-patient anatomy appeared in 51.7% of saved intra-operative images, highlighting a persistent gap between ALARA ('As Low As Reasonably Achievable') principles and real-world practice. To address this problem, we developed a professionally-produced, educational video demonstrating simple, low-cost techniques that maintain working distances during x-ray acquisition. Using common instruments like artery clips, skin hooks, long forceps, and radiolucent syringe barrels, the video provides step-by-step demonstrations tailored to hand surgery. Feedback from national dissemination has been positive, with trainees and consultants circulating the video-based tool. In parallel,Spark Innovation Seedfunding was secured to help design a purpose-built operative tool that allows precise manipulation while keeping the surgeon's hands outside the x-ray field. This article introduces the video as a practical training resource and highlights its potential as a standardised, low-barrier intervention to improve radiation safety in hand surgery.

Operator experience, the use of low frame rates during both fluoroscopy and DSA, and the application of modern medical equipment are crucial for ensuring optimal image quality while maintaining minimal exposure to ionising radiation during cerebral angiography. Our centre achieves this by using the lowest possible fluoroscopy frame rate (3.125 frames per second), a the operator set the nominal acquisition parameters at 2 fps for digital subtraction angiography (DSA), three-dimensional (3D) rotational angiography, two-dimensional /3D mapping, and roadmapping, without compromising the quality of the images obtained. A total of 213 diagnostic procedures for intracranial aneurysms, performed at a single medical centre between 2018 and 2024, were analyzed. Key exposure parameters were collected and analyzed for each procedure, including dose area product (DAP), air kerma (Ka,r), fluoroscopy time (FT), and the total number of DSA frames. The local diagnostic reference level (DRL) and typical values for cerebral angiography were determined and compared with data available in the relevant literature. The 75th percentile (P75) values, assumed to be the DRL, were 23.57 Gy · cm²for DAP (literature range: 90-209), 153 mGy for Ka,r (literature range: 711.3-1401 mGy), 10 min and 46 s for FT, and 257 for the number of DSA frames during diagnostic procedures. Typical values (50th percentile [P50]) were 13.4 Gy · cm²for DAP (literature range: 43.1-157), 92 mGy for Ka,r (literature range: 312-598 mGy), six minutes and 20 s for FT, and 182 for the number of DSA frames during diagnostic procedures. The P50 dose DRLs, measured via DAP, Ka,r, FT, and the number of DSA frames, were at least three times lower at our facility than those reported in studies on cerebral angiography published between 2013 and 2023. The use of low frame rates during both fluoroscopy and DSA has a significant impact on the radiation dose measured by DAP, Ka,r, FT, and the number of DSA frames. The proposed DRLs could be used to ensure quality and patient safety in diagnostic procedures.

Since the beginning of the full-scale war of the Russian federation against Ukraine, there have been serious problems for the Ukrainian healthcare system associated with the substantial loss of medical equipment, evacuation of the public to safer regions, increasing numbers of injuries (military and civilian) due to military activities as well as indiscriminate shelling, etc. Under the special legal regime of martial law, the system of state regulation of nuclear and radiation safety encountered new and unforeseen challenges given the lack of international regulatory experience in the context of full-scale war and the subsequent postwar period. The objective of the work described here is to analyse the current situation in the regulation of medical uses of ionsing radiation, taking into account the decisions taken by the regulatory body, to identify the main risks to the national regulatory system and to suggest ways to improve its robustness and resilience.