Radiation protection research (RPR), particularly its infrastructural aspects, is grappling with numerous challenges. Key among these are financial constraints for hiring permanent technical staff, accessibility issues, and administrative support requirements. The European Partnership for RPR (PIANOFORTE) conducted a workshop to discuss these challenges. The workshop identified a lack of sustained funding for maintaining and upgrading equipment and facilities, retaining skilled staff, and managing databases as the primary hurdles. This paper delves into these challenges in greater detail and proposes policy solutions to strengthen the infrastructure of RPR. It emphasises the need for improved financial models, better accessibility to databases, and more effective training of staff. It also suggests fostering connections with other related databases to share costs and maintain a prevalent digital presence. The goal is to ensure the sustainability and effectiveness of infrastructures within RPR in the European Research Area, thereby leading to improved protection of the public, patients, workers and the environment against exposure to ionising radiation.

From 29th September to 2nd October 2025, European Radiation Protection Week was hosted in London by the UK Health Security Agency with Imperial College London's Department of Epidemiology and Biostatistics. The meeting brought together the platforms under the MEENAS umbrella (MELODI, EURADOS, EURAMED, NERIS, ALLIANCE, and SHARE) to deliver a diverse programme of presentations and posters spanning the breadth of radiation protection research. This paper provides a summary of the meeting.

The system of radiological protection (the 'System') developed by the International Commission on Radiological Protection (ICRP) is built on nearly a century of efforts of numerous scientists and practitioners working together internationally. It rests on three enduring pillars: science, ethics, and experience. These pillars support the three fundamental principles that shape radiological protection strategies: justification, optimisation, and application of dose limits. Of note, optimisation of protection must be understood as a flexible and context-sensitive process, which allows identification of the appropriate level of protection, not simply the lowest dose, taking into account economic, societal and environmental factors. The System has proven effective in protecting workers, patients, members of the public, and the environment in all exposure situations. Effects of high doses, where acute injuries to healthy tissue occur, are rarely observed, and mostly due to accidental situations except for unavoidable side effects of radiotherapy. At low doses, the System is supported by application of the linear-no-threshold model. This model enables prudent (that is, carefully considered given existing uncertainties) policy decisions and estimation of risks at low doses by extrapolation from epidemiological data observed at medium and high radiation doses, acknowledging uncertainty without ignoring potential harm.

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.

The PIANOFORTE partnership (2022–2029) aims to enhance radiation protection for the public, patients, workers, and the environment across various exposure scenarios. This European initiative addresses key barriers in health and environmental risk research related to ionising radiation and promotes findings that support effective radiation protection policies. By building a comprehensive pan-European scientific and technological foundation, PIANOFORTE ensures that the radiation protection system remains fit-for-purpose, delivers science-based policy recommendations and improved practices across sectors using nuclear technology and ionising radiation, including both energy-related and non-energy applications. In the medical field, PIANOFORTE works to reduce uncertainties in health risk estimates and support innovations in cancer diagnosis and therapies. Other key priorities include developing reliable methods for evaluating radiation protection related to new technologies and managing radiation emergencies, improving strategies for both immediate response and long-term recovery. The Partnership's multi-stage prioritisation mechanism of research needs ensures that developed efforts reflect the perspectives of a broad range of stakeholders, including researchers, policy makers, regulators, implementers and practitioners. This inclusiveness aligns research priorities with pressing societal challenges, such as climate change impacts and nuclear technology safety. PIANOFORTE's open call process funds research projects that align with its strategic goals, expanding its network from 58 to 108 partners after inclusion of new partners of granted projects during the two first open calls. Additional calls will continue to foster collaboration and increase research capacity across Europe. By adopting FAIR (Findable, Accessible, Interoperable, and Reusable) data management practices and embracing open science, PIANOFORTE supports the broader radiation protection community in sharing infrastructure and research outcomes. Educational initiatives are central to PIANOFORTE's mission, as it builds Europe's expertise in radiation protection through training programmes for current and next generation scientists. Structured dialogue with stakeholders strengthens the Partnership's impact, bridging research and policy and helping to create a well-informed, resilient society capable of making sound, risk-aware decisions about nuclear and radiation-related issues.

Radiation protection is a cornerstone of public health, occupational safety, patient welfare, and environmental stewardship. A strong emphasis on radiation protection is necessary to contribute to the well-being of citizens, to innovation and sustainable growth across Europe, and to meet the challenges by application of new technologies, and emerging threats. While the use of ionising radiation and radioactive substances underpins significant advancements in medicine, nuclear and non-nuclear industry, it also poses risks that must be carefully defined and managed in environmental and health policies. Effective radiation protection knowledge and know-how help balance the benefits and risks of ionising radiation use, empowering European society to harness its potential safely. Neglecting investment in radiation protection research could lead to increased risks, delayed innovation, and risk-disproportionate radiation protection policy and regulation frameworks, hindering Europe's progress and resilience. This white paper argues for sustained investment in radiation protection research, in the follow-up of the dedicated PIANOFORTE pan-European partnership (2022-2029). In the context of the 10th Framework Programme of Research and Innovation and its related EURATOM's part, this should be achieved with a funding envelop for radiation protection research of ca. 75 M€ through a PIANOFORTE-like partnership, including actions related to infrastructure and education and training. Such investment forms an essential component of Europe's strategy for competitiveness, security, and quality of life, including quality of environmental resources and natural capital, notably but not only in the context of the energy transition. Key challenges related to occupational exposure, medical diagnostics and treatments, emergency preparedness and response, exposure to natural sources of radiation and environmental protection underscore the need for comprehensive research to support evidence-based policy decisions, harmonised regulations and safe, sustainable and integrated practices that address protection of both human and environmental health.

In 2015 the United Nations issued 17 Sustainable Development Goals (SDGs) addressing a wide range of global social, economic, and environmental challenges. The main goal of this paper is to provide an understanding of how the current System of Radiological Protection relates to these SDGs. In the first part it is proposed that the current System of Radiological Protection is implicitly linked to sustainable development. This is substantiated by analysing the features of the current System as set out by the International Commission on Radiological Protection (ICRP) in its publications. In the second part it is proposed that sustainability should be considered and more explicitly addressed in the next ICRP general recommendations, as part of the currently ongoing review and revision of the current System. A few examples are given of how this could be realised, and it is proposed that this issue should be discussed and developed together with the international community interested in radiological protection.

PURPOSE:The Organisation for Economic Co-operation and Development (OECD) Adverse Outcome Pathway (AOP) Development Programme is being explored in the radiation field, as an overarching framework to identify and prioritize research needs that best support strengthening of radiation risk assessment and risk management strategies. To advance the use of AOPs, an international horizon-style exercise (HSE) was initiated through the Radiation/Chemical AOP Joint Topical Group (JTG) formed by the OECD Nuclear Energy Agency (NEA) High-Level Group on Low Dose Research (HLG-LDR) under the auspices of the Committee on Radiological Protection and Public Health (CRPPH). The intent of the HSE was to identify key research questions for consideration in AOP development that would help to reduce uncertainties in estimating the health risks following exposures to low dose and low dose-rate ionizing radiation. The HSE was conducted in several phases involving the solicitation of relevant questions, a collaborative review of open-ended candidate questions and an elimination exercise that led to the selection of 25 highest priority questions for the stated purpose. These questions were further ranked by over 100 respondents through an international survey. This final set of questions was judged to provide insights into how the OECD's AOP approach can be put into practice to meet the needs of hazard and risk assessors, regulators, and researchers. This paper examines the 25 priority questions in the context of hazard/risk assessment framework for ionizing radiation. CONCLUSION:By addressing the 25 priority questions, it is anticipated that constructed AOPs will have a high level of specificity, making them valuable tools for simplifying and prioritizing complex biological processes for use in developing revised radiation hazard and risk assessment strategies.

IntroductionLynch syndrome patients have an inherited predisposition to cancer due to a deficiency in DNA mismatch repair (MMR) genes which could lead to a higher risk of developing cancer if exposed to ionizing radiation. This pilot study aims to reveal the association between MMR deficiency and radiosensitivity at both a CT relevant low dose (20 mGy) and a therapeutic higher dose (2 Gy).MethodsHuman colorectal cancer cell lines with (dMMR) or without MMR deficiency (pMMR) were analyzed before and after exposure to radiation using cellular and cytogenetic analyses i.e., clonogenic assay to determine cell reproductive death; sister chromatid exchange (SCE) assay to detect the exchange of DNA between sister chromatids; γH2AX assay to analyze DNA damage repair; and apoptosis analysis to compare cell death response. The advantages and limitations of these assays were assessed in vitro, and their applicability and feasibility investigated for their potential to be used for further studies using clinical samples.ResultsResults from the clonogenic assay indicated that the pMMR cell line (HT29) was significantly more radio-resistant than the dMMR cell lines (HCT116, SW48, and LoVo) after 2 Gy X-irradiation. Both cell type and radiation dose had a significant effect on the yield of SCEs/chromosome. When the yield of SCEs/chromosome for the irradiated samples (2 Gy) was normalized against the controls, no significant difference was observed between the cell lines. For the γH2AX assay, 0, 20 mGy and 2 Gy were examined at post-exposure time points of 30 min (min), 4 and 24 h (h). Statistical analysis revealed that HT29 was only significantly more radio-resistant than the MLH1-deficient cells lines, but not the MSH2-deficient cell line. Apoptosis analysis (4 Gy) revealed that HT29 was significantly more radio-resistant than HCT116 albeit with very few apoptotic cells observed.DiscussionOverall, this study showed radio-resistance of the MMR proficient cell line in some assays, but not in the others. All methods used within this study have been validated; however, due to the limitations associated with cancer cell lines, the next step will be to use these assays in clinical samples in an effort to understand the biological and mechanistic effects of radiation in Lynch patients as well as the health implications.

PURPOSE:The discovery of X-rays was followed by a variety of attempts to treat infectious diseases and various other non-cancer diseases with ionizing radiation, in addition to cancer. There has been a recent resurgence of interest in the use of such radiotherapy for non-cancer diseases. Non-cancer diseases for which use of radiotherapy has currently been proposed include refractory ventricular tachycardia, neurodegenerative diseases (e.g. Alzheimer's disease and dementia), and Coronavirus Disease 2019 (COVID-19) pneumonia, all with ongoing clinical studies that deliver radiation doses of 0.5-25 Gy in a single fraction or in multiple daily fractions. In addition to such non-cancer effects, historical indications predominantly used in some countries (e.g. Germany) include osteoarthritis and degenerative diseases of the bones and joints. This narrative review gives an overview of the biological rationale and ongoing preclinical and clinical studies for radiotherapy proposed for various non-cancer diseases, discusses the plausibility of the proposed biological rationale, and considers the long-term radiation risks of cancer and non-cancer diseases. CONCLUSIONS:A growing body of evidence has suggested that radiation represents a double-edged sword, not only for cancer, but also for non-cancer diseases. At present, clinical evidence has shown some beneficial effects of radiotherapy for ventricular tachycardia, but there is little or no such evidence of radiotherapy for other newly proposed non-cancer diseases (e.g. Alzheimer's disease, COVID-19 pneumonia). Patients with ventricular tachycardia and COVID-19 pneumonia have thus far been treated with radiotherapy when they are an urgent life threat with no efficient alternative treatment, but some survivors may encounter a paradoxical situation where patients were rescued by radiotherapy but then get harmed by radiotherapy. Further studies are needed to justify the clinical use of radiotherapy for non-cancer diseases, and optimize dose to diseased tissue while minimizing dose to healthy tissue.

The International Commission on Radiological Protection (ICRP) has embarked on a process to review and revise the current System of Radiological Protection ('the System'). To stimulate discussion, the ICRP published two open-access articles: one on aspects of the System that might require review, and another on research that might improve the scientific foundation of the System. Building on these articles, the ICRP organized a Workshop on the Future of Radiological Protection as an opportunity to engage in the review and revision of the System. This digital workshop took place from 14 October-3 November 2021 and included 20 live-streamed and 43 on-demand presentations. Approximately 1500 individuals from 100 countries participated. Based on the subjects covered by the presentations, this summary is organized into four broad areas: the scientific basis, concepts and application of the System; and the role of the ICRP. Some of the key topics that emerged included the following: classification of radiation-induced effects; adverse outcome pathway methodologies; better understanding of the dose-response relationship; holistic and reasonable approaches to optimization of protection; radiological protection of the environment; ethical basis of the System; clarity, consistency and communication of the System; application of the System in medicine and application of the principles of justification and optimization of protection.

The aim of this review is to investigate the literature pertaining to the potential risks of low-dose ionizing radiation to Lynch syndrome patients by use of computed tomography (CT), either diagnostic CT colonography (CTC), standard staging CT or CT surveillance. Furthermore, this review explores the potential risks of using radiotherapy for treatment of rectal cancer in these patients. No data or longitudinal observational studies of the impact of radiation exposure on humans with Lynch syndrome were identified. Limited experimental studies utilizing cell lines and primary cells exposed to both low and high radiation doses have been carried out to help determine radio-sensitivity associated with DNA mismatch repair gene deficiency, the defining feature of Lynch syndrome. On balance, these studies suggest that mismatch repair deficient cells may be relatively radio-resistant (particularly for low dose rate exposures) with higher mutation rates, albeit no firm conclusions can be drawn. Mouse model studies, though, showed an increased risk of developing colorectal tumors in mismatch repair deficient mice exposed to radiation doses around 2 Gy. With appropriate ethical approval, further studies investigating radiation risks associated with CT imaging and radiotherapy relevant doses using cells/tissues derived from confirmed Lynch patients or genetically modified animal models are urgently required for future clinical guidance.

Background: The detrimental health effects associated with the receipt of moderate (0.1-1 Gy) and high (>1 Gy) acute doses of sparsely ionising radiation are well established from human epidemiological studies. There is accumulating direct evidence of excess risk of cancer in a number of populations exposed at lower acute doses or doses received over a protracted period. There is evidence that relative risks are generally higher after radiation exposures in utero or in childhood. Methods and findings: We reviewed and summarised evidence from 60 studies of cancer or benign neoplasms following low- or moderate-level exposure in utero or in childhood from medical and environmental sources. In most of the populations studied the exposure was predominantly to sparsely ionising radiation, such as X-rays and gamma-rays. There were significant (p <0.001) excess risks for all cancers, and particularly large excess relative risks were observed for brain/CNS tumours, thyroid cancer (including nodules) and leukaemia. Conclusions: Overall, the totality of this large body of data relating to in utero and childhood exposure provides support for the existence of excess cancer and benign neoplasm risk associated with radiation doses < 0.1 Gy, and for certain groups exposed to natural background radiation, to fallout and medical X-rays in utero, at about 0.02 Gy.

The International Commission on Radiological Protection (ICRP) has embarked on a review and revision of the system of Radiological Protection that will update the 2007 general recommendations in ICRP Publication 103. This is the beginning of a process that will take several years, involving open and transparent engagement with organisations and individuals around the world. While the system is robust and has performed well, it must adapt to address changes in science and society to remain fit for purpose. The aim of this paper is to encourage discussions on which areas of the system might gain the greatest benefit from review, and to initiate collaborative efforts. Increased clarity and consistency are high priorities. The better the system is understood, the more effectively it can be applied, resulting in improved protection and increased harmonisation. Many areas are identified for potential review including: classification of effects, with particular focus on tissue reactions; reformulation of detriment, potentially including non-cancer diseases; re-evaluation of the relationship between detriment and effective dose, and the possibility of defining detriments for males and females of different ages; individual variation in the response to radiation exposure; heritable effects; and effects and risks in nonhuman biota and ecosystems. Some of the basic concepts are also being considered, including the framework for bringing together protection of people and the environment, incremental improvements to the fundamental principles of justification and optimisation, a broader approach to protection of individuals, and clarification of the exposure situations introduced in 2007. In addition, ICRP is considering identifying where explicit incorporation of the ethical basis of the system would be beneficial, how to better reflect the importance of communications and stakeholder involvement, and further advice on education and training. ICRP invites responses on these and other areas relating to the review of the System of Radiological Protection.

Background: There is accumulating evidence of excess risk of cancer in various populations exposed at acute doses below several tens of mSv or doses received over a protracted period. There is also evidence that relative risks are generally higher after radiation exposures in utero or in childhood.Methods and findings: We reviewed and summarised evidence from 89 studies of cancer following medical diagnostic exposure in utero or in childhood, in which no direct estimates of radiation dose are available. In all of the populations studied exposure was to sparsely ionizing radiation (X-rays). Several of the early studies of in utero exposure exhibit modest but statistically significant excess risks of several types of childhood cancer. There is a highly significant (p < 0.0005) negative trend of odds ratio with calendar period of study, so that more recent studies tend to exhibit reduced excess risk. There is no significant inter-study heterogeneity (p > 0.3). In relation to postnatal exposure there are significant excess risks of leukaemia, brain and solid cancers, with indications of variations in risk by cancer type (p = 0.07) and type of exposure (p = 0.02), with fluoroscopy and computed tomography scans associated with the highest excess risk. However, there is highly significant inter-study heterogeneity (p < 0.01) for all cancer endpoints and all but one type of exposure, although no significant risk trend with calendar period of study. Conclusions: Overall, this large body of data relating to medical diagnostic radiation exposure in utero provides support for an associated excess risk of childhood cancer. However, the pronounced heterogeneity in studies of postnatal diagnostic exposure, the implied uncertainty as to the meaning of summary measures, and the distinct possibilities of bias, substantially reduce the strength of the evidence from the associations we observe between radiation imaging in childhood and the subsequent risk of cancer being causally related to radiation exposure.

La Commission internationale de protection radiologique (CIPR) a initié un examen et une révision du système de radioprotection afin de mettre à jour les recommandations générales de 2007 dans la Publication 103 de la CIPR. Il s’agit du début d’un processus de plusieurs années qui nécessite une collaboration ouverte et transparente avec les organismes et les personnes du monde entier. Bien que le système soit robuste et efficace, il convient de l’adapter à l’évolution des connaissances scientifiques et de la société afin de demeurer adapté aux besoins. Le présent document vise à encourager les discussions sur les domaines du système qui pourraient bénéficier le plus d’un examen, et à engager des initiatives de collaboration. Le renforcement de la clarté et de la cohérence constitue une priorité. Plus le degré de compréhension du système est élevé, plus il est possible de l’appliquer efficacement, ce qui se traduit par une amélioration de la protection et une harmonisation accrue. De nombreux domaines pourraient faire l’objet d’un examen, notamment : la classification des effets, avec un accent particulier sur les réactions tissulaires ; la reformulation du détriment radiologique, qui pourrait inclure les maladies non cancéreuses ; la réévaluation de la relation entre le détriment et la dose efficace, et la possibilité de définir des détriments pour les hommes et les femmes et différentes classes d’âge ; la variation de la réponse individuelle à l’exposition aux rayonnements ; les effets héréditaires ; les effets et risques pour le biote non humain et les écosystèmes. Certains des concepts de base sont également examinés, notamment le cadre permettant de réunir la protection des personnes et de l’environnement, les améliorations progressives des principes fondamentaux de justification et d’optimisation, une approche plus large de la protection des personnes et la clarification des situations d’exposition introduites en 2007. En outre, la CIPR envisage de déterminer dans quels cas l’incorporation explicite des fondements éthiques dans le système présenterait un avantage, comment mieux refléter l’importance des échanges et de l’implication des parties prenantes, et de donner des conseils supplémentaires sur l’éducation et la formation. La CIPR invite à répondre à ces questions et à d’autres liées à l’examen du système de radioprotection.

The question of whether there are excess radiation-associated health risks at low dose is controversial. We present evidence of excess cancer risks in a number of (largely pediatrically or in utero exposed) groups exposed to low doses of radiation (<0.1 Gy). Moreover, the available data on biological mechanisms do not provide support for the idea of a low-dose threshold or hormesis for any of these endpoints. There are emerging data suggesting risks of cardiovascular disease and cataract at low doses, but this is less well established. This large body of evidence does not suggest and, indeed, is not statistically compatible with any very large threshold in dose (>10 mGy), or with possible beneficial effects from exposures. The presented data suggest that exposure to low-dose radiation causes excess cancer risks and quite possibly also excess risks of various non-cancer endpoints.

Purpose The Adverse Outcome Pathway (AOP) framework, a systematic tool that can link available mechanistic data with phenotypic outcomes of relevance to regulatory decision-making, is being explored in areas related to radiation risk assessment. To examine the challenges including the use of AOPs to support the radiation protection community, an international horizon-style exercise was initiated through the Organisation for Economic Co-operation and Development Nuclear Energy Agency High-Level Group on Low Dose Research Radiation/Chemical AOP Joint Topical Group. The objective of the HSE was to facilitate the collection of ideas from a range of experts, to short-list a set of priority research questions that could, if answered, improve the description of the radiation dose-response relationship for low dose/dose-rate exposures, as well as reduce uncertainties in estimating the risk of developing adverse health outcomes following such exposures. Materials and methods The HSE was guided by an international steering committee of radiation risk experts. In the first phase, research questions were solicited on areas that can be supported by the AOP framework, or challenges on the use of AOPs in radiation risk assessment. In the second phase, questions received were refined and sorted by the SC using a best-worst scaling method. During a virtual 3-day workshop, the list of questions was further narrowed. In the third phase, an international survey of the broader radiation protection community led to an orderly ranking of the top questions. Results Of the 271 questions solicited, 254 were accepted and categorized into 9 themes. These were further refined to the top 25 prioritized questions. Among these, the higher ranked questions will be considered as 'important' to drive future initiatives in the low dose radiation protection community. These included questions on the ability of AOPs to delineate responses across different levels of biological organization, and how AOPs could be applied to address research questions on radiation quality, doses or dose-rates, exposure time patterns and deliveries, and uncertainties in low dose/dose-rate effects. A better understanding of these concepts is required to support the use of the AOP framework in radiation risk assessment. Conclusion Through dissemination of these results and considerations on next steps, the JTG will address select priority questions to advance the development and use of AOPs in the radiation protection community. The major themes observed will be discussed in the context of their relevance to areas of research that support the system of radiation protection.

This study aimed to investigate the impact of chronic low-level exposure to chemical carcinogens with different modes of action on the cellular response to ionising radiation. Human lymphoblastoid GM1899A cells were cultured in the presence of 4-nitroquinoline N-oxide (4NQO), N-nitroso-N-methylurea (MNU) and hydrogen peroxide (H2O2) for up to 6 months at the highest non-(geno)toxic concentration identified in pilot experiments. Acute challenge doses of 1 Gy X-rays were given and chromosome damage (dicentrics, acentric fragments, micronuclei, chromatid gaps/breaks) was scored. Chronic exposure to 20 ng/ml 4NQO, 0.25 μg/ml MNU or 10 μM H2O2 hardly induced dicentrics and did not significantly alter the yield of X-ray-induced dicentrics. Significant levels of acentric fragments were induced by all chemicals, which did not change during long-term exposure. Fragment data in combined treatment samples compared to single treatments were consistent with an additive effect of chemical and radiation exposure. Low level exposure to 4NQO induced micronuclei, the yields of which did not change throughout the 6 month exposure period. As for fragments, micronuclei yields for combined treatments were consistent with an additive effect of chemical and radiation. These results suggest that cellular radiation responses are not affected by long-term low-level chemical exposure.