Radiation protection dosimetry最新文献

{"title":"Assessment of thyroid dose in orthopantomogram imaging with different thyroid shield materials: a Monte Carlo simulation study.","authors":"Hassan Vafapour, Soraya Panah, Payman Rafiepour, Seyedeh Roghayeh Panahi","doi":"10.1093/rpd/ncae221","DOIUrl":"10.1093/rpd/ncae221","url":null,"abstract":"<p><p>Radiation protection in dental radiography can be achieved by adjusting the image field size, exposure, and filtration parameters, and using protective lead shields. The aim of this study is to assess the radiation dose delivered to the thyroid in a phantom irradiated by an orthopantomogram (OPG) system using Geant4 simulation toolkit. Recently, researchers have been trying to find an alternative material to the lead thyroid shield so that the OPG image has minimal metal artifacts. In this study, several materials were introduced as alternatives to lead thyroid shields. The results showed that Pb, Bi, Bi2O3, stainless steel, polyurethane-Bi2O3 (50%-50% mixture), and polyurethane-W (50%-50% mixture) shields provide a thyroid dose reduction of up to 12.0%, 12.3%, 12.0%, 11.6%, 11.8%, and 12.0%, respectively. For the truncated thyroid shields, these values are up to 10.5%, 10.3%, 10.3%, 9.80%, 10.0%, and 10.1%, respectively. Therefore, Bi and Bi2O3 can be suitable alternatives to lead thyroid shields.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"48-55"},"PeriodicalIF":0.8,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142829782","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":"Neutron dose estimation by 24Na measurements in the triage of exposed individuals after criticality accidents: a case study of the Tokaimura criticality accident.","authors":"Munehiko Kowatari, Osamu Kurihara","doi":"10.1093/rpd/ncae222","DOIUrl":"10.1093/rpd/ncae222","url":null,"abstract":"<p><p>We investigated the neutron dose estimation for the triage of personnel involved in criticality accidents by conducting 24Na measurements via the whole-body measurement method. For a case study, we examined the September 1999 Japan Nuclear Fuel Conversion Co. criticality accident (internationally known as \"the Tokaimura accident\"). We investigated the neutron-induced radionuclides produced in worker C's body due to the irradiation of the primary pulse. A total of 87 radionuclides were identified, with activities ranging from 1.3 × 10-19 Bq to 6.9 × 106 Bq for worker C by Monte Carlo simulations. The radionuclide with the highest activity was revealed by calculation results: 28Al (t1/2 = 2.2 min) 6.9 × 106 Bq. The specific activity of 38Cl reached a level that was three times that of 24Na. These radionuclides would severely affect the 24Na measurement in the whole-body measurements performed in the immediate post-accident period. Spectrometry would be preferable for determining 24Na specific activities by whole-body measurements at accident sites.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"63-69"},"PeriodicalIF":0.8,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142829786","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":"Implementation of OSL nanoDot dosimetry in different treatment techniques for head and neck cancer.","authors":"Ingrid M Negrete-Hernandez, Ivonne B Lozano, Jesus Roman-Lopez, Jesus I Guzman-Castañeda","doi":"10.1093/rpd/ncae217","DOIUrl":"10.1093/rpd/ncae217","url":null,"abstract":"<p><p>In recent decades, technological advances have been made in the field of radiotherapy and with it the emergence of new dosimetric systems for their calibration and commissioning, among other uses. Such is the case of the measurement in the build-up region, where there is no charged-particle equilibrium, which is reflected in the increase in surface dose for patient treatments and potential skin toxicities as a secondary effect. This study utilizes optically stimulated dosemeters (nanoDot) and the radiochromic film (EBT3) to measure skin doses in patients with head and neck cancer who received radiotherapy. Accurately depicting 15 patients with different diagnoses from 3 linear accelerators using 3D, intensity modulated radiation therapy, or volumetric arc therapy/RapidArc technology, these results were compared with those calculated in the treatment planning system (TPS) and obtaining a percentage of variation for the EBT3 ranged from 0.30% to 6.15%, while that observed for the nanoDot was from 0.51% to 4.88%. This difference may be attributed to the reproducibility of placement in patients. Therefore, for clinical use, nanoDot dosemeters are a viable alternative for in vivo dosimetry where rapid validation of planning system results is required.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"70-77"},"PeriodicalIF":0.8,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142688596","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":"Monte Carlo implementation of a Gaussian plume model for submersion dose calculation at short downwind distances.","authors":"Tommaso Lorenzon, Francesco Bonforte, Luca Codispoti, Stefano Agosteo, Michele Ferrarini","doi":"10.1093/rpd/ncae218","DOIUrl":"10.1093/rpd/ncae218","url":null,"abstract":"<p><p>In this article, the submersion dose due to a radioactive cloud of pollutants was evaluated at short downwind distances from an emission stack. The atmospheric transport of contaminants was modelled using the Gaussian plume model (GPM). The algorithm for dose computation and its hypotheses were analysed. Two relevant issues were discussed: the semi-infinite cloud approximation used for pre-calculated dose conversion factors and the lack of a radiation transport model for dose computation outside the radioactive cloud. The GPM-based software HotSpot and GENII V2.10 and a FLUKA Monte Carlo GPM implementation were compared in a scenario characterized by a low release height and two different simplified atmospheric conditions. Compared to FLUKA, HotSpot and GENII V2.10 results showed a significant dose overestimation inside the plume. Moreover, in extremely stable meteorological conditions, only the Monte Carlo code could detect the ground-level dose contribution from an overhead plume.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"41-47"},"PeriodicalIF":0.8,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142829785","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":"Results of the proficiency test for the Ka CMC of the SSDL-ININ Mexico, for diagnostic radiology IEC 61267:2005 and radiation protection ISO 4037:2019 X-ray beam qualities.","authors":"José Trinidad Álvarez Romero, Gonzalo Walwyn Salas, María de Los Angeles Montes Rodríguez, Mario Raymundo Cabrera Vertti, Andy Luis Romero Acosta","doi":"10.1093/rpd/ncae208","DOIUrl":"10.1093/rpd/ncae208","url":null,"abstract":"<p><p>The present work describes the results for the bilateral comparison between the Secondary Standards Dosimetry Laboratories of the Instituto Nacional de Investigaciones Nucleares (SSDL-ININ), Mexico, and the pilot laboratory, the Centro de Protección e Higiene de las Radiaciones (SSDL-CPHR), Cuba, for the realization of the air kerma (${boldsymbol{K}}_{boldsymbol{a}}$) quantity to: (i) diagnostic X-ray (DXR) IEC 61267:2005 beam qualities: RQR 5 RQR 9, RQT 8, and RQT 9 and (ii) radiation protection (RP) ISO 4037:2019 X-ray beam qualities: N60, N100, and W60, as well S-Cs for gamma radiation. The matched and characterized reference fields are realized at SSDL-ININ with a Toshiba E7252FX X-ray tube. In all cases, the ${boldsymbol{K}}_{boldsymbol{a}}$ measurements are traceable to PTB, except for S-Cs, traceable to ININ. The SSDL-CPHR realizes its reference radiation beam qualities also as matched reference fields with a Pantak HF160C X-ray tube. For the S-Cs beam quality, the CPHR uses a Buchler OB6 irradiator; the ININ, a Siemens Cesagammatron. The transfer ionization chambers calibrated in the RQR and RQT qualities are an Exradin A650/DO70312; for the RQT qualities for CT, a PTW 30009/0655 and RC3CT/9217 were calibrated; and for the RP X-ray qualities, the Exradin A650/DO70312 and a PTW 32002/073 were calibrated. The ratio ${boldsymbol{R}}_{boldsymbol{k}}$ of the resulting calibration coefficients ${boldsymbol{N}}_{{boldsymbol{K}}_{boldsymbol{a}}}$ of each SSDL of the RQR qualities are consistent within the $boldsymbol{U}left(boldsymbol{k}=mathbf{2}right)%$ ≤ 2.3%; for the RQT qualities, the differences are less than the $boldsymbol{U}left(boldsymbol{k}=mathbf{2}right)%$ ≤ 3.6%; and for the RP X-ray qualities, within the order of $boldsymbol{U}left(boldsymbol{k}=mathbf{2}right)%$ ≤ 3.5%. For the S-Cs quality, the ${boldsymbol{R}}_{boldsymbol{k}}$ is in the order of $boldsymbol{U}left(boldsymbol{k}=mathbf{2}right)$ ≤ 3.0%. It should be noted that the ININ U's are generally larger due to the failure of the ${boldsymbol{k}}_{boldsymbol{TP}}$ correction factor, a brief discussion is given here. The ${boldsymbol{E}}_{boldsymbol{n}}$ score from ISO 17043 provides statistical support to this comparison.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"31-40"},"PeriodicalIF":0.8,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142828965","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":"Radiological risk assessment of phosphate fertilizer application on farmlands in Ondo State, Nigeria.","authors":"Olajide Kehinde Ogunbiyi, Tolulope Ayodeji Ojuola, Alaba Tolulope Agbele, Funmilola Olusola Ogunlana, Ojo Emmanuel Oludare, Abdul-Hafiz Abolade Alabi","doi":"10.1093/rpd/ncae214","DOIUrl":"10.1093/rpd/ncae214","url":null,"abstract":"<p><p>This study assesses the radiological risks associated with phosphate fertilizer application on farmlands in Ondo State, Nigeria. Soil samples from ten agricultural towns were analyzed for radionuclide concentrations using gamma-ray spectrometry. Primordial radionuclides such as 238U, 232Th, and 40K were examined, with 40K showing the highest concentration due to the potassium-rich nature of phosphate fertilizers. Spatial variability in radionuclide concentrations was observed, attributed to agricultural activities. Despite variations, mean activity concentrations were below global averages, indicating low radiological risks. Hazard indices, radium equivalent concentrations, and absorbed dose rates were all within safe limits. The annual effective dose equivalent was significantly lower than recommended levels, and excess lifetime cancer risk estimates were below the global average. The study emphasizes the importance of educating farmers on the potential adverse effects of radionuclides and recommends reducing the use of inorganic fertilizers to promote eco-friendly agricultural practices.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"1997-2007"},"PeriodicalIF":0.8,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142606037","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":"From age-specific to size-specific dose protocol for paediatric head computed tomography: a simple practical strategy for necessity assessment and parameter setting.","authors":"Liwei Hu, Rongzhen Ouyang, Jing Li, Guozhi Zhang, Jiong Li, Chen Guo, Qian Wang, Yumin Zhong","doi":"10.1093/rpd/ncae202","DOIUrl":"10.1093/rpd/ncae202","url":null,"abstract":"<p><p>This study proposes a practical approach to assessing the need for and determining the transitioning parameters from age-specific to size-specific dose protocols in paediatric head computed tomography examinations. It was designed to begin with the two different age-specific protocols currently applied on paediatric patients of 1 y ≤ age ≤ 6 y (21.34 mGy) and those of age >6 y (34.73 mGy). One characteristic size (HDthreshold) was found by measuring anteroposterior head diameter on historical topograms and used with age to set 135 cases into four groups for investigation (A, ≤6y, ≤HDthreshold; B, ≤6y, >HDthreshold; C, >6y, ≤HDthreshold; and D, >6 y, >HDthreshold). The image quality was compared in both subjective and objective manners. Results suggest patients in Group C may have received a potential overdose (38%), while the exposure setting for Group D may replace that for B. The proposed strategy was sufficient to assess the necessity and determine the transitioning parameters from age- to size-specific dose protocols.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"1981-1989"},"PeriodicalIF":0.8,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142473290","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":"Modelling of constant and realistic chronic intake scenarios and their implications.","authors":"Sushanta Halder, Minal Yesuraja Nadar, Lokpati Mishra, Deepak Kumar Akar, Jogendra Yadav, Indrasen Singh, Pramilla Sawant, Probal Chaudhury","doi":"10.1093/rpd/ncae213","DOIUrl":"10.1093/rpd/ncae213","url":null,"abstract":"<p><p>Chronic inhalation intake of radionuclides is possible for radiation workers in the nuclear industry. The International Commission on Radiological Protection (ICRP) provides organ retention fractions as well as daily urinary and fecal excretion for chronic intake of various radionuclides. In this study, organ retention fractions and daily urinary excretion for chronic intake were estimated for constant chronic intake (CCI) and realistic chronic intake (RCI) scenarios. CCI is a daily intake of 1 Bq, and RCI is an intake of 1.4 Bq for five working days followed by two days gap. Radiologically important radionuclides such as 239Pu, 60Co, 137Cs, 131I, and 3H having long, moderate, and short effective half-lives in the deposited organ or whole body were considered. The retention fractions and daily urinary excretion of all the radionuclides studied for RCI were found to converge with those for the CCI scenario at ~40 to 200 days except for daily urinary excretion of 131I.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"2021-2028"},"PeriodicalIF":0.8,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142606107","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":"Monte Carlo simulation study of the effect of thyroid shielding on radiation dose in dental cone beam CT in an adult male phantom.","authors":"Guolin Chen, Yuchen Yin, Liang Sun, Zichun Tang, Jianguo Chen","doi":"10.1093/rpd/ncae206","DOIUrl":"10.1093/rpd/ncae206","url":null,"abstract":"<p><p>In this paper, the effect of thyroid collars on radiation dose during dental cone-beam computed tomography (CBCT) was evaluated using Monte Carlo simulations and to calculate the effective dose underestimated for the actual CBCT examination due to accounting only for the head and neck. Three thyroid collar models that covered the surface of the phantom were established according to the International Commission on Radiological Protection (ICRP) adult-male mesh-type reference computational phantoms, and a Particle and Heavy Ion Transport code System was used to calculate the equivalent and effective doses of ICRP phantom when different thyroid shielding protocols were used in NewTom VGi evo CBCT, considering one medium (12 × 8 cm) and one small (8 × 5 cm) fields of view (FOVs), and two centre positions were used for each FOV. In four CBCT scanning scenarios, thyroid shielding reduced the equivalent dose for many tissues. The results indicate that the portion of the thyroid collar that wraps around the neck has the main role in reducing the effective dose during dental CBCT examinations, and the higher the axial level of the top of the shielding, the better the effectiveness of the shielding. In this study, the underestimation of the effective dose due to considering only the head and neck was 3.1%-8.1%, and the underestimation was more pronounced in larger FOVs.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"1971-1980"},"PeriodicalIF":0.8,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142473291","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":"Assessment of radiological contamination due to gold mining in soil and food crops of Babban Tsauni, Gwagwalada, Nigeria.","authors":"Kafayat Abdulrasheed Odelami, Mark Omotola Afolayan Oladipo, Michael Akor Onoja, Yahaya Musa, Saudat Olabisi Aremu","doi":"10.1093/rpd/ncae207","DOIUrl":"10.1093/rpd/ncae207","url":null,"abstract":"<p><p>This work assessed the activity concentrations of 238U(226Ra), 232Th, and 40K and their associated radiological risks due to exposure to soil and consumption of food crops in Babban Tsauni artisanal gold mine, Gwagwalada, Nigeria, using the gamma spectrometry technique. The mean activity concentrations of 226Ra, 232Th, and 40K in the mine soil were 60.2 ± 9.9, 161.4 ± 16.2, and 664.6 ± 138.2, while they were 46.4 ± 4.9, 79.9 ± 39.3, 266.4 ± 185.4 for tubers and 46.9 ± 15.7, 100.5 ± 35.8, 311.4 ± 132.7 (Bq/kg) for grains, respectively. The results reveal that the activity concentrations of radionuclides in all samples exceeded the recommended values set by United Nations Scientific Committee on the Effects of Atomic Radiation (33, 45, and 420 Bq/kg) except 40K, which fell within the acceptable limit in all food crop sample types. Estimated results for radiological hazard parameters, radium equivalent, annual effective dose due to ingestion, and excess life cancer risk were within safe limits, while the annual effective dose due to external gamma radiation in soil and annual gonadal equivalent dose were significantly high in all investigated samples; these call for constant radiological monitoring.</p>","PeriodicalId":20795,"journal":{"name":"Radiation protection dosimetry","volume":" ","pages":"1961-1970"},"PeriodicalIF":0.8,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142473288","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}