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type:Text, Individual external doses for the first 4 months after the Fukushima accident have been estimated by the 'Basic Survey' of the Fukushima Health Management Survey. On the other hand, the UNSCEAR 2013 report presented the first-year effective dose due to external radiation for each municipality in nonevacuated areas of Fukushima Prefecture. In this study, the doses estimated by the Basic Survey were averaged for each of three age groups (infants, 0-5 y; children, 6-15 y; and adults, >16 y), in accordance with the categories adopted by the UNSCEAR report. The average dose ratios (infants/adults and children/adults) obtained from the Basic Survey were 1.08 and 1.06 for nonevacuated areas, respectively. These were smaller than the estimation by the UNSCEAR report (1.7 and 1.4, respectively). Three factors (body size factor, location factor and occupancy factor) were discussed and the location and occupancy factors were likely to be reasons for the difference.

A nationwide network with participation from academic and professional societies,equipment suppliers, government authorities, and individual experts, called J-RIME,set the first national DRLs in June 2015 and updated them in July 2020. In this review, the contents of Japan DRLs and the process of their development were overviewed.

Although several cases of radiation-induced skin injury (RSI) have been reported in association with neurointerventional procedures such as endovascular embolization for cerebral aneurysm, cerebral arteriovenous malformation, and dural arteriovenous fistula, in most cases the absorbed doses are not measured directly; therefore, we built the first direct measurement system that enables the ideal dosimetry for entrance skin dose (ESD) during neurointerventional procedures to be easily determined. This system was then applied to a 55-year-old man who underwent two transvenous embolizations with a 2-month interval, for a right cavernous sinus dural arteriovenous fistula, to establish the efficacy of precise mapping of ESDs. Throughout the procedures, the patient wore a fitted dosimetry cap that contained 60 radiophotoluminescence glass dosimeter (RPLGD) chips. After the first procedure, temporary epilation occurred in the occipital region. Precise mapping of ESDs revealed that this region was exposed to 4.2 Gy. In the first procedure, the X-ray tube was generally positioned straight for an optimal posterior–anterior view; however, in the second procedure we intermittently used the second-best position to prevent further RSI. In this position, the maximum ESD was 1.0 Gy in the right posterior-temporal region and the epilation site was exposed to ≤0.7 Gy. Thus, the patient did not develop any further epilation. We conclude that direct dosimetry using multiple RPLGDs can accurately reveal the maximum ESD and that precise information regarding ESD can prevent further RSIs from subsequent procedures.

type:Text, Following the Fukushima Daiichi Nuclear Power Plant accident, a survey for estimating individual external doses for the first 4 months after the accident was started, and it remains ongoing. Since the authors' previous paper, 44 605 new dose estimates have been made. The new dose estimates increase the number of dose estimates to 465 999 and are reported in this note. Since the previous paper, most of the recently collected responses have been gotten through public relations activities to encourage responses across the prefecture. Thus, recent respondents might be biased ('selection bias'). Also, the dose estimates were based on self-administered responses about personal behaviour, which relied on memories of residents. In this respect, incorrect behaviour records possibly resulted as memories have faded over time ('recall bias'). However, the effects of these biases on dose distribution on a whole-prefecture basis seemed to be small.

In 2012 IRPA established a task group(TG)to identify key issues in the imple-mentation of the revised eye lens dose limit. The TG reported its conclusions in2013. In January 2015, IRPA asked the TG to review progress with the imple-mentation of the recommendations from the early report and to collate currentpractitioner experience. This report presents the results of a survey on the view ofthe IRPA professionals on the new limit to the lens of the eye and on the widerissue of tissue reactions. Recommendations derived from the survey are presented.This report was approved by IRPA Executive Council on 31 January 2017.

In 2012 IRPA established a task group (TG) to identify key issues in the implementation of the revised eye lens dose limit. The TG reported its conclusions in 2013. In January 2015, IRPA asked the TG to review progress with the implementation of the recommendations from the early report and to collate current practitioner experience. This report presents the results of a survey on the view of the IRPA professionals on the new limit to the lens of the eye and on the wider issue of tissue reactions. Recommendations derived from the survey are presented. This report was approved by IRPA Executive Council on 31 January 2017., Postprint (published version)

type:Text, Many studies have been conducted on radiation doses to residents after the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident. Time spent outdoors is an influential factor for external dose estimation. Since little information was available on actual time spent outdoors for residents, different values of average time spent outdoors per day have been used in dose estimation studies on the FDNPP accident. The most conservative value of 24 h was sometimes used, while 2.4 h was adopted for indoor workers in the UNSCEAR 2013 report. Fukushima Medical University has been estimating individual external doses received by residents as a part of the Fukushima Health Management Survey by collecting information on the records of moves and activities (the Basic Survey) after the accident from each resident. In the present study, these records were analyzed to estimate an average time spent outdoors per day. As an example, in Iitate Village, its arithmetic mean was 2.08 h (95% CI: 1.64-2.51) for a total of 170 persons selected from respondents to the Basic Survey. This is a much smaller value than commonly assumed. When 2.08 h is used for the external dose estimation, the dose is about 25% (23-26% when using the above 95% CI) less compared with the dose estimated for the commonly used value of 8 h.

本報告書は、医学用の原子分子・原子核データに興味を持っている分野の専門家の方々を対象にしたアンケート調査結果を、おもに放射線に関係した物理工学の専門家の視点から分析しまとめたものである。以下の3点の重要性を確認した。(1)医学を支えている物理工学,化学薬学などの基礎データと、医学の直接的な関連データに大きく分類すると、基礎データより関連データがより重要な医学分野では、生体に関連するデータの整備を、その使い勝手の良さも含めて行う必要がある。(2)基礎データは、データの質,量,精度など、現状でも多くの医療現場の要求にほぼ十分に対応できていた。ただし、情報化社会の状況でのデータの利用ついては、医学分野に特化した特殊ファイルと、それを生体の関連データに反映させる理論や計算コード等の利用システムの整備など、総合的に体制を整備していく時期にある。(3)利用分野の発展には、基礎データの完成度を高めておくことは不可欠なことから、限りある資源や人材を効率的に活用するという現実を直視しながら、基礎データの整備拡充を、今後とも地道に計画的に継続性を持って進めていく必要がある。, This report provides an analysis of the results of the survey conducted among field experts regarding the data on atoms, molecules, and atomic nuclei used in medical applications. The important results are summarized as follows: First, the importance of the basic data for disciplines involved in medical research, i.e. physics and engineering, chemistry, pharmacology, biology, and the related data which are applied directly in medicine were identified. The related data are of greater importance in direct medical application compared to conventional basic data. Therefore, the data related to biology should be prepared in consideration of their convenient usage. Second, regarding the fundamental data on atoms, molecules and atomic nuclei related to medicine, the present data was able to approximately cope with the demands of many medical cases that needed data on quality, quantity, precision, etc. However, we found situations particularly in the IT community where comprehensively organized data was urgently needed. The data to be used for practical implementation must contain the specialized data for medical physics and biology. Finally, the significance of the continuity in the planned completion of the basic data was confirmed for the development of the associated fields. The expansion and completion of basic data should be done continuously and effectively while considering the limitation in resources and manpower., 著者所属: 日本原子力研究開発機構(JAEA), JAEA-Review 2006-002