Area Dose-Response and Radiation Origin of Childhood Thyroid Cancer in Fukushima Based on Thyroid Dose in UNSCEAR 2020/2021: High 131I Exposure Comparable to Chernobyl.

The FMU and the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) concluded that the high incidence of thyroid cancer after the Fukushima nuclear accident was not the result of radiation exposure, but rather might have been overdiagnosis based on the low thyroid dose estimated in the UNSCEAR 2020/2021 report. In this study, the origin of increased PTC in Fukushima was examined based on the thyroid dose estimated by UNSCEAR. The dose-response relationship of the incidence rate per person-years (PY) was analyzed for four areas in Fukushima prefecture via regression analysis. The linear response of the annual incidence rates to thyroid dose in the first six years showed that the dominant origin of childhood thyroid cancer was radiation exposure. Excess absolute risk (EAR) proportionally increased with thyroid dose, with an EAR/104 PY Gy of 143 (95%CI: 122, 165) in the second TUE (p < 0.001), which is approximately 50-100 times higher than the EAR/104 PY Gy ≒ 2.3 observed after the Chernobyl accident. This suggests an underestimation of the thyroid dose by UNSCEAR of approximately 1/50~1/100 compared with the thyroid dose for Chernobyl. The increased childhood thyroid cancer in Fukushima was found to arise from radioactive iodine exposure, which was comparable to that in Chernobyl.

Reflections on effects of low doses and risk inference based on the UNSCEAR 2021 report on 'biological mechanisms relevant for the inference of cancer risks from low-dose and low-dose-rate radiation'.

The 2021 United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) report summarises the knowledge on biological mechanisms of radiation action at low doses where, due to low statistical power of epidemiological investigations, the level of cancer risk must be inferred. It is the fourth UNSCEAR report since 1994 that looks into biological effects following low dose exposure with the aim of examining whether they support the assumption of the linear non-threshold (LNT) dose response for radiation-induced cancers. The conclusions of all four reports are affirmative. The new aspect of the 2021 report is that it focuses on the process of cancer risk inference. The aim of this article is to discuss the consequences of the conclusions regarding LNT and the possibilities of inferring risks from biological studies.

[Ten Years from the Fukushima Daiichi Nuclear Accident: Were the Predicted Effects Reported by Worldwide Experts Correct?]

Since the Fukushima Daiichi Nuclear Power Station accident (hereinafter referred to as the "Fukushima Daiichi accident") occurred in March 2011, many experts around the world have conducted the assessments on radiation doses and health effects attributed to the Fukushima Daiichi accident. During the months soon after the accident while the state of the nuclear reactor was not accurately grasped, the radiation exposure of the residents was estimated based on the predicted environmental behavior of various radionuclides. However, there were significant differences in the estimated doses and effects presented by different researchers and research institutes. As investigations on the causes and progress of the Fukushima Daiichi accident have progressed in last 10 years, now we know better the situation and consequence of the accident. In this article, the contents of relevant papers and reports published during the three years (-2014) after the Fukushima Daiichi accident are briefly reviewed and then compared with the relatively new scientific information obtained in 2015 or later. Through these analyses, the author tries to look back on how correct or incorrect the initial estimates were.

Lung cancer risk and effective dose coefficients for radon: UNSCEAR review and ICRP conclusions.

The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has provided a detailed and authoritative update of its reviews of the epidemiology and dosimetry of radon and progeny. Lifetime risk of lung cancer calculated using data for several miner cohorts were 2.4-7.5 × 10-4per working level month (WLM) of radon-222 progeny exposure for a mixed male/female population and 3.0-9.6 × 10-4per WLM for a male population. Dosimetric models gave mean values of effective dose coefficients from radon-222 progeny of 12 mSv per WLM for mines, 16 mSv per WLM for indoor workplaces and 11 mSv per WLM for homes. The lifetime risk coefficient used by the International Commission on Radiological Protection (ICRP) is 5 × 10-4per WLM and it has recently recommended an effective dose coefficient for radon-222 and progeny of 3 mSv per mJ h m-3(about 10 mSv per WLM) for most circumstances of exposure. The ICRP risk and dose coefficients are supported by the UNSCEAR review and provide a clear and firm basis for current international advice and standards for protection from radon. Notwithstanding this evidence and the ICRP advice, UNSCEAR will continue to use a lower value of effective dose coefficient of 5.7 mSv per WLM for assessments of population exposures.

The Great East Japan Earthquake, Tsunamis, and Fukushima Daiichi Nuclear Power Plant Disaster: Lessons for Evidence Integration from a WADEM 2017 Presentation and Panel Discussion.

In April 2017, some of the health impacts of the 2011 Great East Japan Earthquake, tsunamis, and resultant Fukushima Daiichi nuclear power plant disaster (Okuma, Fukushima Prefecture, Japan) were presented at the 19th Congress of the World Association for Disaster and Emergency Medicine (WADEM; Madison, Wisconsin USA) in Toronto, Canada. A panel discussion was then opened by asking audience members about their experiences in their own countries, and how they would suggest taking steps to reach the goals of the Sendai Framework for Disaster Risk Reduction 2015-2030. This paper summarizes the presentation and panel discussion, with a particular focus on the common problems identified in understanding and reducing health risks from disasters in multiple countries, such as the ethical and practical difficulties in decision making on evacuating vulnerable populations that arose similarly during the Fukushima nuclear disaster in 2011 and Hurricane Ike's approach to Galveston (Texas USA) in 2008. This paper also highlights the need for greater integration of research, for example through increased review and collation of evidence from different disaster settings to identify common problems and possible solutions, which was identified in this panel session as a precursor to fulfilling the goals of the Sendai Framework.Leppold C, Ochi S, Nomura S, Murray V. The Great East Japan Earthquake, tsunamis, and Fukushima Daiichi nuclear power plant disaster: lessons for evidence integration from a WADEM 2017 presentation and panel discussion. Prehosp Disaster Med. 2018;33(4):424-427.

Current Status of the Blue Butterfly in Fukushima Research.

Adverse biological impacts of the Fukushima nuclear accident have been revealed using the pale grass blue butterfly, Zizeeria maha, since 2012, which were often considered incompatible with the conventional understanding of radiation biology. This discrepancy likely originates from different system conditions and methodologies. In this article, we first respond to comments from the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) regarding our study; "technical errors" in unit usage and mathematical models noted by UNSCEAR are not errors but reflect our research philosophy not to introduce theoretical assumptions associated with unit conversion and mathematical fit. Second, we review our recent studies to support the original 2012 conclusions. Because the high morphological abnormality rate and small body size detected in Fukushima in 2011 have already ceased, likely through adaptive evolution, their present geographical distributions were investigated throughout Japan. Local populations showing relatively high abnormality rates and small body sizes were rare and basically restricted to Miyagi and its northern populations excluding the Fukushima populations, supporting the causal involvement of the accident. Lastly, we stress the importance of understanding the whole picture of the biological impacts of the Fukushima accident. In addition to the direct radiation impacts, indirect impacts through unknown radiation-associated mechanisms, such as immunological responses to insoluble particulate matter and nutritional deficiencies in plants and animals, would be in effect. Further environmental studies beyond conventional radiation biology and physics are necessary to understand the complex responses of organisms, including humans, to the Fukushima nuclear accident.

Radiation Doses and Associated Risk From the Fukushima Nuclear Accident.

The magnitude of dose due to the Fukushima Daiichi Accident was estimated by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) 2013 report published in April 2014. Following this, the UNSCEAR white paper, which comprises a digest of new information for the 2013 Fukushima report, was published in October 2015. Another comprehensive report on radiation dose due to the accident is the International Atomic Energy Agency (IAEA) report on the Fukushima Daiichi Accident published in August 2015. Although the UNSCEAR and IAEA publications well summarize doses received by residents, they review only literature published before the end of December 2014 and the end of March 2015, respectively. However, some studies on dose estimation have been published since then. In addition, the UNSCEAR 2013 report states it was likely that some overestimation had been introduced generally by the methodology used by the Committee. For example, effects of decontamination were not considered in the lifetime external dose estimated. Decontamination is in progress for most living areas in Fukushima Prefecture, which could reduce long-term external dose to residents. This article mainly reviews recent English language articles that may add new information to the UNSCEAR and IAEA publications. Generally, recent articles suggest lower doses than those presented by the UNSCEAR 2013 report.

History and Organizations for Radiological Protection.

International Commission on Radiological Protection (ICRP), an independent international organization established in 1925, develops, maintains, and elaborates radiological protection standards, legislation, and guidelines. United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) provides scientific evidence. World Health Organization (WHO) and International Atomic Energy Agency (IAEA) utilise the ICRP recommendations to implement radiation protection in practice. Finally, radiation protection agencies in each country adopt the policies, and adapt them to each situation. In Korea, Nuclear Safety and Security Commission is the governmental body for nuclear safety regulation and Korea Institute of Nuclear Safety is a public organization for technical support and R&D in nuclear safety and radiation protection.

History and Organizations for Radiological Protection

International Commission on Radiological Protection (ICRP), an independent international organization established in 1925, develops, maintains, and elaborates radiological protection standards, legislation, and guidelines. United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) provides scientific evidence. World Health Organization (WHO) and International Atomic Energy Agency (IAEA) utilise the ICRP recommendations to implement radiation protection in practice. Finally, radiation protection agencies in each country adopt the policies, and adapt them to each situation. In Korea, Nuclear Safety and Security Commission is the governmental body for nuclear safety regulation and Korea Institute of Nuclear Safety is a public organization for technical support and R&D in nuclear safety and radiation protection.

The impact of the Fukushima nuclear accident on marine biota: retrospective assessment of the first year and perspectives.

An international study under the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) was performed to assess radiological impact of the nuclear accident at the Fukushima-Daiichi Nuclear Power Station (FDNPS) on the marine environment. This work constitutes the first international assessment of this type, drawing upon methodologies that incorporate the most up-to-date radioecological models and knowledge. To quantify the radiological impact on marine wildlife, a suite of state-of-the-art approaches to assess exposures to Fukushima derived radionuclides of marine biota, including predictive dynamic transfer modelling, was applied to a comprehensive dataset consisting of over 500 sediment, 6000 seawater and 5000 biota data points representative of the geographically relevant area during the first year after the accident. The dataset covers the period from May 2011 to August 2012. The method used to evaluate the ecological impact consists of comparing dose (rates) to which living species of interest are exposed during a defined period to critical effects values arising from the literature. The assessed doses follow a highly variable pattern and generally do not seem to indicate the potential for effects. A possible exception of a transient nature is the relatively contaminated area in the vicinity of the discharge point, where effects on sensitive endpoints in individual plants and animals might have occurred in the weeks directly following the accident. However, impacts on population integrity would have been unlikely due to the short duration and the limited space area of the initially high exposures. Our understanding of the biological impact of radiation on chronically exposed plants and animals continues to evolve, and still needs to be improved through future studies in the FDNPS marine environment.

Resultados de la vigilancia radiológica individual de la exposición externa en Cuba en el período 2006-2009 / Results of personal dosimetry in Cuba from 2006 to 2009 period

RESUMEN El trabajo describe los resultados del servicio de dosimetría personal del Laboratorio de Dosimetría Externa del Centro de Protección e Higiene de las Radiaciones en el período 2006-2009. Se analizan los datos sobre el número de trabajadores ocupacionalmente expuestos que son monitoreados y los niveles de exposición ocupacional que reciben, comparándolos con períodos anteriores y los valores publicados por el UNSCEAR. Los trabajadores monitoreados laboran en la medicina, la industria convencional, la investigación y la docencia. El sector de la salud abarca el 90%. El número de trabajadores monitoreados mantuvo una tendencia creciente en el período, siendo el caso más relevante la práctica de radiodiagnóstico, la cual se duplicó. El número de trabajadores ocupacionalmente expuestos, fue inferior al 50% del total monitoreado, mostrando una tendencia decreciente con respecto a años anteriores. La dosis anual promedio para todas las prácticas fue inferior a 1 mSv, mostrando igualmente una disminución con respecto al período anterior.

ABSTRACT The work describes the results of the personal dosimetry service carried out by the External Dosimetry of the Center for Radiation Protection and Hygiene from 2006 to 2009. Data about number of monitored occupationally exposure workers and occupational radiation exposure levels are analyzed, which are also compared with previously period and UNSCEAR reports. The results show that the number of occupational exposure workers is increase in the period; only about 50% of monitored workers were exposed. The average individual values of annual effective doses were less than 1 mSv for all monitored practices. The comparison with previously period showed a decreasing tendency in the number of exposed workers and in the average annual doses.

Impacto radiológico de las fuentes naturales y artificiales de radiación. El informe UNSCEAR 2008 / Radiological impact of artificial and natural radiation sources. UNSCEAR 2008 Report

RESUMEN Se presentan los resultados del informe del Comité Científico de Naciones Unidas para el Estudio de los Efectos de las Radiaciones Atómicas presentado en el 56período de sesiones de julio del 2008 y se comparan los valores obtenidos según los tipos de fuentes naturales o artificiales y de acuerdo con el efecto sobre las personas. Se concluye que el cambio más significativo en la situación entre informes fue el aumento en la exposición médica debido al incremento de los exámenes de tomografía computarizada.

ABSTRACT The present paper shows the results of the report from the United Nations Scientific Committee on the Effects of Atomic Radiation, presented at the 56th session on July 2008. The values obtained according to the types of natural or artificial sources and their effect on people are compared. It is concluded that the most significant change in the situation has been the increase in medical exposure due to the increase in CT examinations.