Health physics最新文献

{"title":"Discrete Bayesian Dose-response Analysis under Dose Uncertainty.","authors":"Eduard Hofer","doi":"10.1097/HP.0000000000001965","DOIUrl":"10.1097/HP.0000000000001965","url":null,"abstract":"<p><p>Establishing a relationship between disease and dose requires each individual in the population under investigation to be known by disease status and by the value of the dose received. Frequently, the dose values are reconstructed using a dose assessment model containing imprecisely known parameter values, model formulations, and input data (epistemic uncertainties). As a consequence, the state of knowledge of the assessed dose values needs to be expressed by a joint subjective probability distribution thereby accounting for state of knowledge dependence due to uncertainties shared by the assessed dose values of several individuals. Dose-response analysis must apply this joint state of knowledge in obtaining a subjective probability distribution for the parameters of the dose-response model. This is achieved by drawing a random sample of dose vectors according to the joint distribution, by applying Bayes' theorem for each vector, and by averaging the posterior parameter distributions (Bayesian model averaging). If the dose response is quantified by a binary variable, a logistic regression model is embedded in the likelihood function. This paper presents a new, computationally efficient Bayesian model averaging method that operates over the discretized parameter space and thereby does away with the computational complexities of Bayesian methods. It corrects for the attenuation effect that is due to the application of dose vectors other than the true vector. Results obtained for a sample of dose vectors are compared to those obtained with the standard discrete Bayesian method using the true dose vector.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"331-338"},"PeriodicalIF":1.4,"publicationDate":"2025-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143500682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Radiation Dose to Occupational Dosimeters Brought on Commercial Air Travel.","authors":"Lienard Chang, Daniel W Kim","doi":"10.1097/HP.0000000000001955","DOIUrl":"10.1097/HP.0000000000001955","url":null,"abstract":"<p><strong>Abstract: </strong>Occupational radiation dosimeters that return high readings cannot always be explained by circumstances in the workplace. For this experiment, a series of optically stimulated luminescence (OSL) dosimeters were brought to airports to estimate the radiation dose OSLs would receive should a worker accidentally bring their dosimeter with them during travel. The OSLs returned readings between 0.77 and 3.70 mSv. While factors such as scanning times, machine modality and model, flight duration, and elevation changes can all affect dosimeter readings, this small experiment provides a general range of dose readings to dosimeters to assist radiation safety program managers in quantifying true radiation dose from the workplace.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"302-304"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143058810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proposed Probabilistic Optimization of Radioactive Waste Disposal Facility Design Considering Long-term Uncertainty.","authors":"Kazuma Kuroda, Ryo Nakabayashi, Daisuke Sugiyama","doi":"10.1097/HP.0000000000001960","DOIUrl":"10.1097/HP.0000000000001960","url":null,"abstract":"<p><strong>Abstract: </strong>In the optimization of radioactive waste disposal facility design, it is important to compare multiple facility design options with the aim of reducing the effective dose as low as reasonably achievable. In this study, a methodology for optimizing the facility design using a probabilistic approach was proposed, and two case studies were provided the application of the methodology and interpretation of the dose distributions. This methodology incorporates the time integration of the 95th percentile value and the sum of coefficients of variation extracted from the probability distribution of dose profile over time as the indicators for relative comparison on the optimization. This methodology enables consideration of the dose with uncertainty for the entire long-term assessment period in the optimization. This allows a more multifaceted comparison of options and is expected to improve the ability to explain optimization with the consideration of long-term uncertainty. While various factors including economic, social, and possibly others are relevant to the decision process, this study focuses on the dose estimations as an indicator for optimization. In the case studies, intermediate-depth disposal in Japan, which is one of the disposal systems of low-level radioactive waste, is used as an example and the groundwater release scenario was the focus. The comparison of multiple options in low-diffusivity and low-permeability layers were assumed. These are the important factors in the migration of radioactive nuclides, while other parameters can also be considered in optimization by using the proposed methodology.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"271-284"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12379771/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143414091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evolution of Diagnostic Medical Physics Enterprise.","authors":"Ryan Misseldine, Ryan Kocak, Andrew Dietz, Ronald Leuenberger, David Jordan","doi":"10.1097/HP.0000000000001942","DOIUrl":"10.1097/HP.0000000000001942","url":null,"abstract":"<p><strong>Abstract: </strong>The roles and responsibilities of radiation safety officers (RSO), medical health physicists (MHP) and diagnostic medical physicists (DMP) have evolved significantly over the past 20 years. With the availability of enterprise software systems and aggregated data platforms for various radiologic healthcare systems, the roles of these professions are expanding beyond their original scopes in managing the Radioactive Materials License (RSO, MHP) and Machine Specific Physics Testing (DMP). Workers in medical radiation safety are transitioning from siloed workers working within their specific disciplines as new emerging technology and clinical care require these roles to evolve. This paper aims to demonstrate the value in embracing the change in these roles to better serve the patients and occupational workers RSOs, MHPs, and DMPs serve. As medical physics enterprise solutions evolve, so will the relationships between these valuable stakeholders.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"315-323"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142800564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Studies on Shielding and Activation Levels in a Concrete-Iron-Concrete Sandwich Structure Wall in the CMUH Proton Therapy Facility.","authors":"Po-Wen Fang, Ying-I Hsieh, An-Cheng Shiau, Rong-Jiun Sheu","doi":"10.1097/HP.0000000000001943","DOIUrl":"10.1097/HP.0000000000001943","url":null,"abstract":"<p><strong>Abstract: </strong>The shielding performance and activation susceptibility of a sandwich wall in the proton therapy facility of China Medical University Hospital were investigated in an integrated manner using FLUKA Monte Carlo simulations. The 2-m-thick partition wall between two adjoining treatment rooms had a three-layered structure, which comprised a 0.2-m-thick iron layer sandwiched between two layers of 0.9-m-thick concrete. In comparison with that of a concrete wall of the same thickness, the shielding performance of the concrete-iron-concrete wall was marginally better, further reducing the transmitted dose rate by approximately a factor of 2 against secondary neutrons generated through proton bombardment. This study also investigated radioactivity levels from long-lived radionuclides ( 3 H, 22 Na, 54 Mn, 55 Fe, 60 Co, 134 Cs, 152 Eu, and 154 Eu) that are primarily induced in concrete or iron by neutrons. The specific activities of 54 Mn, 55 Fe, and 60 Co in the middle iron layer were considerably higher (by factors of 75, 25, and 5, respectively) than those in the neighboring concrete. However, as for clearance levels, the index value of the iron layer was lower than that of the neighboring concrete because of the presence of fewer types of long-lived radionuclides in iron. Under irradiation scenarios considered in this study, the residual activity levels of the sandwich wall do not exceed those of a full-concrete wall, and the indexes at various depths estimated at 5 years cooling following a 20-y operational period comply with clearance criteria.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"307-314"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142947836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the Excess Lifetime Cancer Risk from Water in the Euphrates River, Najaf, Iraq.","authors":"Ali Yahya Salman, Shaymaa Awad Kadhim, Hussain M Hussain, Fadhil I Sharrad","doi":"10.1097/HP.0000000000001959","DOIUrl":"10.1097/HP.0000000000001959","url":null,"abstract":"<p><strong>Abstract: </strong>Water is the basic element for the continuation of human life for all inhabitants, animals and plants on Earth, and water cannot be dispensed with as it is a basis of life. This study focuses on measuring radiation to assess activity levels of some radionuclides in the waters of the Euphrates River, which is the main tributary of drinking water in Najaf, Iraq, and determining whether it is safe for health in terms of radiation. The concentrations of three gamma-emitting nuclides ( 226 Ra, 232 Th, and 40 K) were measured in a section of the Euphrates River using gamma-ray spectroscopy using a 3\" × 3\" sodium iodide scintillation detector doped with thallium and connected to software version MAESTRO-32. Twenty-nine water samples were collected at regular intervals along the Euphrates River within the administrative boundaries of Al-Najaf Al-Ashraf Governorate. The Al-Mishkab branch results showed activity concentration levels of 226 Ra, 232 Th, and 40 K that are 3.182 ± 1.514, 1.572 ± 0.509, and 26.715 ± 17.082 Bq L -1 , respectively. For Al-Qadesia branch, the activity concentrations are equal to 3.190 ± 1.350, 2.190 ± 1.082, and 37.135 ± 29.464 Bq L -1 , respectively, which is within the maximum acceptable concentration levels recommended by the World Health Organization. The annual effective ingestion dose (EID) due to the specific activities of the three nuclides is equal to 0.311 ± 0.103 and 0.357 ± 0.144 mSv y -1 for the Al-Mishkab branch and the Al-Qadesia branch, respectively. The excess lifetime cancer risk (ELCR) values are 1.197 ± 0.395 and 1.373 ± 0.553 × 10 -3 for the Al-Mishkab and Al-Qadesia branches, respectively. Therefore, the study concluded that radiation levels in the river water are a significant risk to public health because the concentrations of the studied nuclides are higher than what is globally permitted according to the U.S. Environmental Protection Agency.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"245-255"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143709717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis Method of 131 I Activity in Carbon Cartridge and Internal Dose Assessment for Nuclear Medicine Workers.","authors":"Shuo Wang, Fei Tuo, Jian-Feng Zhang, Xiao-Liang Li, Bao-Lu Yang, Qiang Zhou, Ze-Shu Li, Shu-Ying Kong, Wei-Hao Qin","doi":"10.1097/HP.0000000000001954","DOIUrl":"10.1097/HP.0000000000001954","url":null,"abstract":"<p><strong>Abstract: </strong>Inhalation of 131 I is the main route for internal doses to nuclear medicine workers. This study aimed to establish a simple analysis method for determining 131 I activity in carbon cartridges, explore the activity concentration of 131 I in nuclear medicine departments, and evaluate the internal dose of workers. A total of 21 nuclear medicine departments in the hospital conducted air sampling using a high-volume air sampler equipped with carbon cartridges and glass fiber filters to collect gaseous 131 I and aerosol 131 I, respectively. Furthermore, a mathematical model was developed to analyze the 131 I activity with inhomogeneous distribution in cartridges. Based on the 131 I activity measured by the HPGe γ spectrometer, the personal annual inhalation effective dose was estimated. The results showed that there is a significant difference in the activity of gaseous 131 I and aerosol 131 I, with the activity ranging from 1.5±0.08 Bq m -1 to 3,944.23±197.21 Bq m -3 and ND (not detectable) to 842.11±42.11 Bq m -3 , respectively. The activity of aerosol 131 I is about 1% to 7% of that of gaseous 131 I. The annual committed effective dose caused by inhalation of 131 I for workers is 3.6 μSv to 8.23 mSv, which is lower than the dose limit of 20 mSv y -1 . In general, the 131 I contamination in the nuclear medicine department cannot be ignored, and the concentration of 131 I should be regularly monitored to prevent and control the internal radiation to which workers may be exposed.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"225-232"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142970572","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preliminary Study of Dose Rates to Rhinoceros Basal Cells from a Radioactive Source to Deter Poaching.","authors":"Jordan A Hillis, Craig M Marianno, Thomas E Johnson, James Larkin","doi":"10.1097/HP.0000000000001953","DOIUrl":"10.1097/HP.0000000000001953","url":null,"abstract":"<p><strong>Abstract: </strong>The five populations of rhinoceros species have declined in the wild due to poaching and habitat degradation, with demand for rhinoceros horn driving the poaching industry. The poaching of rhinoceros horn has critically threatened the conservation status of over half of these animals in the world today. To combat this threat and safeguard the species, a method involving the insertion of a radiation source into the rhinoceros's horn has been proposed. This approach aims to deter poachers due to public fear of radiation and enable the detection of smuggled horns based on the source's radioactive properties. To determine the health risks to the rhinoceros, this study presents the dose rate response functions to the rhino's epithelial basal stem cells that form the horn. The assessed responses assumed a modeled source centered at 10 and 20 cm above the basal stem cells. To identify the most appropriate source, dose rates were produced from gamma sources ranging from 0.1 to 2 MeV. Using numerical calculations, conservative dose rate estimates were determined as a function of energy and normalized to source activity, providing a foundation for computational results using Monte Carlo N-Particle Code version 6.2. With the dose rate responses as a function of energy and activity, the risk of deterministic and stochastic effects in this most at-risk tissue were understood based on the skin dose limitations for preventing deterministic effects to the rhinoceros.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"293-301"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143656991","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Effect of X-ray Security Imaging on Optically Stimulated Luminescence Personnel Dosimetry.","authors":"Derek Lewis, Connor Williams, Seth Kanter","doi":"10.1097/HP.0000000000001958","DOIUrl":"10.1097/HP.0000000000001958","url":null,"abstract":"<p><strong>Abstract: </strong>Federal regulations mandate that all radiological workers in the United States, as well as those individuals who may receive non-trivial occupational doses of radiation, must have their external radiation doses monitored and tracked as accurately as possible. Typically, this is done through the use of personnel dosimetry devices, such as optically stimulated luminescence (OSL) dosimeters, which are worn on the body and keep an accurate record of the radiation to which a person has been exposed over a period of time. Unfortunately, the inadvertent passage of OSL dosimeters through airport x-ray security scanners can compromise the accuracy of this running dose record and therefore impede the ability for employers to accurately report work-related doses. With the advent of advanced resolution security technology used in many airports, this once relatively minor issue now requires that the Idaho National Laboratory (INL) Radiological Controls organization be able to accurately discern non-occupational doses received in this way. This research will discuss the methods and models for adjusting dose readings for Landauer InLight Model 2 OSL personnel dosimeters used at the INL that have been subjected to three types of x-ray scans commonly used at airport checkpoints, and the implications of these data across the rest of the US DOE complex.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"256-270"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143630351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Changes of Lymphocytes and Immune Molecules in Irradiated Mice by Different Doses of Radiation.","authors":"Tingyu Yang, Rong Gao, Yehui Gao, Mingyue Huang, Jialu Cui, Lin Lin, Hongbo Cheng, Wanyun Dang, Yue Gao, Zengchun Ma","doi":"10.1097/HP.0000000000001957","DOIUrl":"10.1097/HP.0000000000001957","url":null,"abstract":"<p><strong>Abstract: </strong>The effects of different radiation doses on T and B lymphocyte functional subsets and the changes of immune cells and immune molecules were observed in mice at different times post-irradiation to provide a theoretical basis for the changes of immune cells affected by radiation. In this study, the changes of T and B immune cells and immune-related molecules were observed at 1, 3, 7, 14, and 21 d after single irradiation of 2 Gy, 4 Gy, and 6 Gy. The results showed that white blood cells (WBC), lymphocytes (LYMPH), and lymphocyte percentage (LYMPH%) in peripheral blood of mice were significantly reduced and reached the lowest point 3 d after irradiation. Flow cytometry results showed that the percentages of CD3 + T and CD8 + /CD3 + T lymphocytes in spleen and thymus were significantly decreased, and the percentages of CD19 + B lymphocytes in spleen and CD4 + /CD3 + T lymphocytes in thymus were also decreased. However, the percentages of splenic NK cells, CD4 + /CD3 + T cells, and CD4 + /CD8 + ratios in spleen and thymus were increased. Most of the indicators fell to the lowest or highest point 3 d after irradiation, indicating that immune function was suppressed at this time. From 7 to 21 d after irradiation, most immune cells gradually recovered. Single irradiation of 2 Gy, 4 Gy, and 6 Gy increased the contents of IL-1β, IL-2, IL-6, IL-17, TNF-α, TGF-β, and IFN-γ in serum of mice and decreased the contents of anti-inflammatory factors IL-4 and IL-10. The serum levels of immunoglobulin IgA, IgG, IgM and complement C3, C4 were significantly increased after irradiation. Our study showed that a single dose of 2 Gy, 4 Gy, and 6 Gy induced immunosuppression in mice, and maximum immunosuppression was achieved 3 d after irradiation. At this time, CD19 + B lymphocytes were the most sensitive, followed by CD3 + T lymphocytes, and NK cells were the most resistant. The radiosensitivity of CD8 + /CD3 + T lymphocytes was slightly higher than that of CD4 + /CD3 + T lymphocytes.</p>","PeriodicalId":12976,"journal":{"name":"Health physics","volume":" ","pages":"233-244"},"PeriodicalIF":1.4,"publicationDate":"2025-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143065299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}