Radiation protection dosimetry最新文献

{"title":"Dose estimation for astronauts using adult mesh-type reference computational phantoms.","authors":"Ye Cai, Qinjian Cao, Yuan Zhao, Hua Li, Xiaofeng Wei, Yu Wang, Liye Liu","doi":"10.1093/rpd/ncag099","DOIUrl":"https://doi.org/10.1093/rpd/ncag099","url":null,"abstract":"<p><p>Astronaut radiation exposure in low Earth orbit is strongly affected by orbital radiation environment, shielding condition, and radiation quality. In this study, a Geant4-based Monte Carlo model coupled with the adult male mesh-type reference computational phantom of the International Commission on Radiological Protection (ICRP) was developed to estimate organ doses for astronauts in the Chinese Space Station (CSS) orbit. Proton and electron spectra from the Earth's radiation belts (ERB) were calculated using AP9/AE9, and solar-minimum galactic cosmic ray (GCR) spectra were generated using CREME96. Organ absorbed dose, $Q(L)$-based organ dose equivalent and effective dose equivalent were calculated for two representative exposure scenarios: extravehicular activity (EVA) with spacesuit-equivalent shielding and intravehicular activity (IVA) with spacecraft shielding. The calculated effective dose equivalent rates in the CSS orbit were 1006 μSv d-1 during EVA and 571 μSv d-1 during IVA. ERB protons were the dominant contributor to organ absorbed dose and effective dose equivalent under both shielding conditions. ERB electrons contributed mainly to superficial tissues during EVA and were almost completely attenuated under IVA conditions. After spacecraft shielding, GCRs became more important for dose-equivalent-based quantities because of their high penetration capability and high-LET components. The calculation method was evaluated by additional ISS-orbit simulations and comparison with MATROSHKA measurements and previous PHITS calculations. Good agreement was obtained for IVA exposure, whereas larger deviations during EVA were mainly associated with simplified local shielding geometry and the sensitivity of superficial tissue doses to low-energy ERB particles. The comparison between CSS and ISS orbits showed that astronaut dose levels cannot be inferred from orbital altitude alone, because different orbital inclinations lead to different ERB and GCR spectra. The present results provide organ-specific dose data for astronauts in the CSS orbit and support radiation protection assessment for future long-duration missions.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148866667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Eye lens dose distribution in neonatal head CT: an analysis of the scanning conditions and CTDIvol limitations.","authors":"Tatsuhiro Gotanda, Takuya Akagawa, Tomoyuki Hasuo, Shinnosuke Nishihara, Kohsei Matsuura, Yasuyuki Kawaji, Hidetoshi Yatake, Shinya Imai, Rumi Gotanda, Toshizo Katsuda","doi":"10.1093/rpd/ncag046","DOIUrl":"10.1093/rpd/ncag046","url":null,"abstract":"<p><p>Despite neonatal radiosensitivity, accurate lens dose assessments in computed tomography (CT) are lacking. We assessed the neonatal head CT eye lens dose under various scanning conditions, including vertical table displacement and organ-based exposure modulation (OEM), using the GAFCHROMIC LD-V1 (LD-V1), which can measure two-dimensional dose distributions, and we evaluated the limitations of conventional dose indices. The lens dose decreased with increasing distance from the isocentre for the Canon 320. Whereas, for the Canon 80 and Siemens, the dose peaked at +25 mm and then decreased. For the OEM, the dose reduction effect decreased at 30°. The CT dose index volume remained consistent. Spatially resolved dosimetry using the LD-V1 reveals beam overlap and positioning-related dose anomalies that cannot be captured by point dosimeters or conventional indices. The LD-V1 can effectively evaluate superficial dose distributions and guide dose optimization in neonatal imaging.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"1096-1107"},"PeriodicalIF":0.8,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147964530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proposal for a new operational quantity for eye lens photon dosimetry.","authors":"Kamal Bouzegzi, Akila Frahi-Amroun","doi":"10.1093/rpd/ncag054","DOIUrl":"10.1093/rpd/ncag054","url":null,"abstract":"<p><p>In the past, little attention was given to measuring the radiation dose received by the lens of the eye. It was assumed that limiting the total body dose to 20 mSv per year provided adequate protection for the lens in all practical workplace situations. However, after the International Commission on Radiological Protection (ICRP) issued a statement proposing to reduce the limit for occupational exposure from 150 to 20 mSv per year, the importance of eye-lens photon dosimetry increased. This work proposes a new operational quantity D(6)water as an alternative to Hp (3) for evaluating the dose received by the lens of the eye. The proposed quantity is a physical one, which means it can be measured directly. Fluence-to-D(6)water conversion coefficients are calculated for photon energies ranging from 0.02 to 10 MeV using the Monte Carlo transport code EGSnrc without resorting to the kerma approximation, meaning a more accurate and realistic radiation dose assessment. Comparison of the conversion coefficients with those of the absorbed dose to the lens of the eye (Dlens), published by the ICRP shows that D(6)water can adequately represent Dlens over the entire considered energy range.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"1108-1111"},"PeriodicalIF":0.8,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148016968","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"AI-driven triage classification at the 1 Gy threshold using dietary supplements and portable OSL dosimetry.","authors":"Sara Della Monaca, Nadica Maltar-Strmečki, Maria Cristina Quattrini, Emanuela Bortolin","doi":"10.1093/rpd/ncag053","DOIUrl":"10.1093/rpd/ncag053","url":null,"abstract":"<p><p>In radiological emergency scenarios, the rapid distinction between individuals exposed below or above the 1 Gy triage threshold is essential for effective medical sorting and optimized resource allocation. This study proposes a binary classification framework at the 1 Gy threshold that combines Optically Stimulated Luminescence (OSL) measurements of commercial magnesium-based dietary supplements with supervised machine learning (ML) algorithms, including Logistic Regression, Support Vector Machines, Decision Trees, Random Forest, and XGBoost. A dataset of 355 samples exposed to different radiation doses was analyzed, and model performance was evaluated using cross-validation and multiple statistical metrics. The resulting framework was implemented into a lightweight, browser-based application to provide real-time predictions and support decision-making in field operations. The findings demonstrate that integrating physical dosimetry with ML enables rapid and scalable classification relative to the 1Gy threshold and offers a practical tool to enhance public health response during radiological incidents.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"1144-1153"},"PeriodicalIF":0.8,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148043430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exposure of the palm to handheld wireless devices operating at frequencies from 900 MHz to 6 GHz.","authors":"Andreas Christ, Kai Niskala, Kenneth H Joyner","doi":"10.1093/rpd/ncag052","DOIUrl":"10.1093/rpd/ncag052","url":null,"abstract":"<p><p>The exposure of the palm due to handheld wireless devices is analyzed using anatomical hand models of adults and children considering a frequency range from 900 MHz to 6000 MHz. The fingers of the hand models are articulated such that they hold the phone model in realistic positions. The antennas of the phone model are located in the microphone region, which maximizes the exposure of the palm. Approximately 140 configurations are evaluated numerically. The exposure is quantified in terms of the 10 g psSAR and compared with the psSAR calculated for a flat phantom. The results indicate that the exposure of the palm is within the extremity exposure limit of 4 W per kg in $sim $96% of the cases for the hand models if the exposure limits are met for a flat phantom at 0 mm distance. The numerical uncertainty for the exposure evaluation is assessed as 24.7% ($k=2$).</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"1154-1162"},"PeriodicalIF":0.8,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148151032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mailed dose record review of occupational dosimetry records among Japanese medical radiation workers: the OREMS Study.","authors":"Hiroko Kitamura, Natsuko Hatsusaka, Hiroshi Sasaki, Takashi Moritake","doi":"10.1093/rpd/ncag045","DOIUrl":"10.1093/rpd/ncag045","url":null,"abstract":"<p><p>Occupational dose records in Japan are retained by employers, with no national registry, complicating epidemiological exposure assessments. In the Epidemiological Study on Occupational Radiation Exposure in Medical Staff, the feasibility of a mailed dose record review was evaluated among participants who underwent occupational radiation health surveillance (ORHS) at six annual conferences (November 2020-October 2024). Dose information was obtained for 182 individuals (44.9% of eligible participants). The median cumulative effective dose was 2.3 [25th, 75th percentile: 0.3, 11.7] mSv, and median cumulative duration was 8.5 [3.8, 19.8] years. For the fiscal year prior to ORHS, annualized median values were 0.1 mSv for effective dose (E), 0.6 mSv for equivalent dose to the lens of the eye (Heye), and 0.6 mSv for equivalent dose to the skin (Hskin) (values below the detection limit were set to 0.0 mSv), presented descriptively to characterize data properties in this feasibility study. Interventional radiology physicians tended to show higher cumulative and annualized doses than neuro-spine physicians in this descriptive feasibility analysis.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"1081-1095"},"PeriodicalIF":0.8,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147869466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Field assessment of radon exposure in three zirconium and titanium mineral processing plants: radon concentrations, individual progeny concentrations, size distributions, etc.","authors":"Kang Peng, Chen Lin, Jinmin Yang, Mingfa Xu, Wei Zhang, Libo Jia, Yue Jiang, Lei Zhang, Qiuju Guo, Limin Zhang","doi":"10.1093/rpd/ncag047","DOIUrl":"10.1093/rpd/ncag047","url":null,"abstract":"<p><p>Naturally-Occurring Radioactive Materials (NORM), such as uranium, radium, and thorium, can lead to elevated radon exposure among workers and the public. In certain mineral processing facilities-such as those handling zirconium and titanium-exceptionally high concentrations of uranium and thorium are present, necessitating field surveys and radon exposure assessments from a radiation protection management perspective. This study investigated three typical factories in Qinzhou, southern China. Measurements were conducted in workplaces for gamma dose rates, radon and thoron progeny concentrations, and key physical characteristic parameters of radon-thoron progeny. Dose conversion factors (DCFs) for radon and thoron were calculated using the TAURUS software. Results indicate an average radon activity concentration of 14.67 ± 0.39 Bq/m3, while the average equilibrium equivalent radon concentration (EERC) and equilibrium equivalent thoron concentration (EETC) were 2.64 ± 0.09 Bq/m3 and 2.45 ± 0.07 Bq/m3, respectively. Elevated gamma dose rates were observed in some workplaces. For characteristic parameters, the average activity median diameter of attached radon/thoron progeny (AMDa) was 218 nm and 206 nm, with geometric standard deviations (GSDa) of 1.7 and 1.8, respectively. The average activity median diameter of unattached progeny (AMDu) was 1.32 and 2.18 nm, with GSDu values of 1.3 and 1.2. The DCF for radon progeny was calculated as 32.5 nSv/(Bq·m-3·h), and for thoron progeny as 149 nSv/(Bq·m-3·h). In workplaces, the estimated annual effective dose for workers primarily stems from gamma radiation and thoron exposure, with contributions of 0.67 and 0.44 mSv, respectively. In contrast, radon exposure contributed only 0.11 mSv. When both workplaces and dwellings are considered, the total estimated annual effective dose was 3.59 mSv, with gamma radiation, radon, and thoron making comparable contributions on average.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"1112-1119"},"PeriodicalIF":0.8,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148034572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of a real-time dose display system as a behavioural intervention to improve radiation protection in fluoroscopy: a pilot study.","authors":"Keisuke Nagamoto, Yoshiki Suetsugu, Aina Yamamoto, Masaoki Kohzaki, Ryuji Okazaki","doi":"10.1093/rpd/ncag050","DOIUrl":"10.1093/rpd/ncag050","url":null,"abstract":"<p><p>This pilot study evaluated the educational and behavioural effects of a real-time radiation dose visualization system during upper gastrointestinal fluoroscopy. Fifty-one procedures (pre-intervention, n = 26; post-intervention, n = 25) by seven radiologists were analysed. Occupational dose Hp(10) showed no detectable difference after implementation [median 27 vs 26 μSv; median difference -2.0 μSv, 95% confidence intervals (CI) -11.0 to +7.0; P = .637]. The normalized index Hp(10)/cumulative air kerma (C-AK) was similarly unchanged (median 446.5 vs 450.9 μSv/Gy; difference +22.9 μSv/Gy, 95% CI -108.8 to +147.9; P = .785). Procedural metrics showed no significant variation (C-AK: P = .385; fluoroscopy time: P = .487; images: P = .084). Post-intervention questionnaires indicated increased awareness of radiation exposure and reinforcement of protective behaviour. The large-screen interface provided immediate, intuitive feedback and functioned as a behavioural safety tool aligned with experiential learning principles. Real-time visual feedback may enhance radiation protection education by improving awareness and promoting reflective behavioural learning, even when immediate reductions in measured dose are not observed.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"1120-1130"},"PeriodicalIF":0.8,"publicationDate":"2026-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148034569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Slice-resolved ocular dosimetry in pediatric axial CT using a validated Geant4 Monte Carlo framework.","authors":"Nouf Abuhadi, Omrane Kadri, Kais Manai","doi":"10.1093/rpd/ncag097","DOIUrl":"https://doi.org/10.1093/rpd/ncag097","url":null,"abstract":"<p><p>Accurate evaluation of eye lens exposure during pediatric computed tomography (CT) examinations is essential for radiation protection because the lens is among the most radiosensitive organs in the human body. In this study, a scanner-specific Monte Carlo framework based on Geant4 (v11.02.p2) was developed to quantify slice-resolved absorbed dose to the eye lens and selected head organs in pediatric axial CT imaging. The CT system was modeled in detail, including X-ray spectra, bowtie filtration, beam collimation, and source geometry. Beam quality was tuned using half-value layer and lateral beam profile measurements. Model validation was performed through comparison with experimental computed tomography dose index ratios, ${text{CTDI}}_{text{air}}/{text{CTDI}}_{w}$, for tube voltages between 80 and 140 kVp and collimations between 10 and 40 mm, showing agreement within 2%. Simulations using 10 pediatric voxel phantoms based on International Commission on Radiological Protection-143 reference models revealed a strong dependence of ocular dose on acquisition parameters and patient anatomy. Although absolute eye-lens dose differed substantially between the two acquisition configurations, normalization relative to brain dose showed that beam collimation altered the eye-to-brain dose ratio by only about 6%. However, reducing tube voltage from 140 to 80 kVp decreased eye lens dose by $sim $86% in newborn phantoms. The proposed framework enables detailed slice-resolved assessment of ocular exposure beyond conventional CTDI-based estimates and provides a robust tool for evaluating pediatric CT protocols and supporting optimization strategies aimed at improving radiation protection of radiosensitive tissues.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2026-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148831951","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of hand skin radiation doses from accidental 131I and 18F radiopharmaceutical contamination during nuclear medicine procedures.","authors":"Akbar Abbasi, Vali Bashiry, Fatemeh Mirekhtiary, Serap Maden, Ahmed H Ali","doi":"10.1093/rpd/ncag101","DOIUrl":"https://doi.org/10.1093/rpd/ncag101","url":null,"abstract":"<p><p>Iodine-131 (131I) and fluorine-18 (18F) are widely used radionuclides in nuclear medicine; however, accidental localized contamination of the hands may occur during radiopharmaceutical preparation, dispensing, administration, or contaminated-material handling. This study presents a scenario-based computational assessment of hand skin dose from 131I and 18F contamination using the SkinDose module of VARSKIN/V+. Skin equivalent dose coefficients were calculated as a function of exposure time and normalized per unit spilled activity as mSv/MBq. For 18F, the cumulative dose increased rapidly during the first few hours and approached a plateau due to its short physical half-life. For 131I, dose accumulation continued over the evaluated period because of its longer physical half-life. The results provide practical reference dose coefficients for radiation-protection assessment of localized hand contamination, while emphasizing that they should be interpreted within the limits of the defined scenarios and realistic contamination-management conditions.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":""},"PeriodicalIF":0.8,"publicationDate":"2026-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148831956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}