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Health Physics
Journal Prestige (SJR): 0.528  Citation Impact (citeScore): 1 Number of Followers: 6  Hybrid journal (It can contain Open Access articles)ISSN (Print) 0017-9078 - ISSN (Online) 1538-5159 Published by LWW Wolters Kluwer  [330 journals]
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- Uranium Mine Proposed Experimental Design for Natural Background Gross
Gamma Exposure Rates, Post Remediation Final Status Survey Sampling
Density, and Radiological Water Quality Modeling for a Worst-case
Catastrophic Failure, Coles Hill, Virginia-
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Authors: Weyant; David B.; Yoon, Jaewan
Abstract:
Completely randomized experimental design statistical modeling techniques were employed to analyze exposure rate measurements for evaluating hypothetical natural background post uranium mill operations at Coles Hill, Virginia uranium milling processes. The proposed Coles Hill Uranium Mine is situated upstream of the Banister River. This River is nearly homogenous throughout the reach length used in analysis and feeds into the mouth of Kerr Reservoir, Lake Gaston, which serves as the main drinking water source for cities in the Hampton Roads area including Norfolk, Virginia Beach, and Chesapeake. A critical scan value (=DCGLscan) was developed to flag anomalies of surface contamination during simulated post remediation final status surveys. The natural background was critical for meeting the Multi-Agency Radiation Survey and Site Investigation Manual guidance for post remediation final status surveys. The overarching null hypothesis suggested that the selected mean natural background is equal to the survey unit’s mean natural background. Using SAS Procedures Shapiro-Wilk Test, ANOVA, and CR, it was decided the exposure rate data was normal, had no extreme outliers, and no collinearity between the number of samples (=treatment) and the areas (=block). Using the q-hyper (hypergeometric) distribution, the soil sampling density was decided for a final status survey unit. The most likely worst-case catastrophic failure analysis, 500-year event, such as the1969 Hurricane Camille of 69 centimeters of rain in Nelson County, Virginia was included in the model. The model showed impact was minimal at most to the Banister River’s drinking water and likely less than the Virginia’s Drinking Water Standards for gross alpha, 226Ra and 228Ra, and total uranium.
PubDate: Sun, 01 Sep 2024 00:00:00 GMT-
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- Overt Scientific Bias and Clandestine Acts by Trusted Scientists: The
Flawed Application of the Linear No-threshold Model-
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Authors: Cardarelli; John J. II
Abstract: The Health Physics Society (HPS) released a video documentary on the history of the linear no-threshold (LNT) model in April 2022. It exposed many scientific and ethical failings of many leaders, influential scientists, and organizations that have resulted in the current system of radiological protection. Since then, the society received many comments; most were supportive, while a few criticized the video documentary as delivering an anti-LNT message. Shortly thereafter, many emails discovered via an independent Freedom of Information Act request revealed multiple layers of coordination between prominent people in the field of radiation protection to coopt the leadership within the HPS and suppress information they perceived or assumed to be contrary to a pro-LNT message. Many of these emails were published by JunkScience.com, an independent organization that exposes faulty scientific data and analyses used to advance special interests and hidden agendas. This Forum article is intended to document in the peer-reviewed literature the JunkScience.com findings of clandestine acts by trusted scientists within the radiation protection community. The emails exposed strong personal biases, actions taken by leaders within the National Commission on Radiation Protection and Measurements (NCRP) to “save the Society” from its “downward spiral,” and actions taken by NCRP and HPS members serving on a National Academies of Sciences committee to suppress scientific information relevant to the debate about health effects in low-dose environments. These anti-science actions harm our entire profession and the trust that Congress bestows on our scientific organizations expecting to receive objective recommendations based on sound science. It is important that these events are recorded in the scientific literature from a historical perspective. The radiation protection community will be judged not by what is revealed in this article but by what actions are taken from here.
PubDate: Sun, 01 Sep 2024 00:00:00 GMT-
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- THE HEALTH PHYSICS SOCIETY: An Affiliate of the International Radiation
Protection Association (IRPA)-
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Abstract: No abstract available
PubDate: Sun, 01 Sep 2024 00:00:00 GMT-
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- HEALTH PHYSICS SOCIETY . 2024 AFFILIATE MEMBERS
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Abstract: No abstract available
PubDate: Sun, 01 Sep 2024 00:00:00 GMT-
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- Modeling Fallout from Nuclear Weapon Detonations: Efficient Activity and
Dose Calculation of Radionuclides and Their Progeny-
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Authors: van Dijk; Arjan; de Bode, Michiel; Kloosterman, Astrid; van der Linden, Marte; Tomas, Jasper M.
Abstract:
The purpose of this paper is to present a practical method for quick determination of potential radiological doses and contaminations by fallout from nuclear detonations, or other releases, that includes the contributions from all nuclides. We precalculate individual (total) activities of all radionuclides from any initial cocktail and all their ingrowing progeny at a set of pinpoints in time with a logarithmic time-spacing. This is combined with the set of dose conversion factors (DCC) for any exposure pathway to obtain a time-dependent cocktail for the whole release as if it is one substance. An atmospheric dispersion model then provides the thinning coefficient of the released material to give local concentrations and dose rates. Progeny ingrowth is illustrated for pure 238U and for a nuclear reactor that has been shut down. Efficient dose assessment is demonstrated for fallout from nuclear detonations and compared with the traditional approach of preselecting nuclides for specific endpoints and periods-of-interest. The compound cocktail DCC reduces the assessment of contaminations and potential dose-effects from fallout after a nuclear detonation to (the atmospheric dispersion of) only one tracer substance, representing any cocktail of nuclides and their progeny. This removes the need to follow all separate nuclides or an endpoint-specific preselection of “most important nuclides.” As the cocktail DCCs can be precalculated and the atmospheric dispersion of only one tracer substance has to be modelled, our method is fast. The model for calculating cocktail DCCs is freely available, easily coupled to any regular atmospheric dispersion model, and therefore ready for operational use by others.
PubDate: Thu, 11 Jul 2024 00:00:00 GMT-
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- Has Health Physics Contributed to an 80-y False Narrative about the
Trinity Nuclear Test'-
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Authors: Shonka; Joseph J.
Abstract:
This paper discusses the various analyses of the Trinity Nuclear Test, including how they might apply to the issue of infant mortality. This paper was first drafted as a response to a letter by Rice, who commented on my earlier letter on that issue. My earlier letter commented on the National Cancer Institute’s 2020 series of papers in the October Issue of Health Physics on the impact of the Trinity Nuclear Test that was conducted on unoccupied government lands on 16 July 1945. The Journal editors requested that my response to Rice be edited and submitted as a paper to ensure adequate technical review and suggested that the article also add material summarizing the series of exchanges that were published in the Journal. This article suggests that significant differences exist between various summaries of the offsite impact of the Trinity Nuclear Test and offers that Trinity might be the largest nuclear accident in terms of the impact on uninvolved civilians who were downwind following the test. It suggests areas for further study to resolve these significant differences. It also asserts that until the estimated exposures of downwind residents are resolved and an appropriate study is made of infant deaths following the Trinity Nuclear Test, the issue of infant mortality remains an unanswered, 80-y-old question.
PubDate: Sat, 15 Jun 2024 00:00:00 GMT-
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- Consequences of Violating Conditions of Counting Statistics Are Not Severe
when Measuring Radon Progeny Concentrations with the Thomas and Kusnetz
Methods-
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Authors: Jenkins; Phillip H.
Abstract:
When analyzing samples of radon progeny using the Thomas or Kusnetz methods, we violate one of the conditions of counting statistics because we use counting times that are not short compared with the half-lives of the radionuclides. The result is that we overestimate the uncertainties of the counts if we use counting statistics without correction. In this work, I describe the method by which I adjusted the values of variance of the counts theoretically to values that are more accurate and calculated the amounts by which I overestimate the values of counting uncertainty by using counting statistics without correction. These values are surprisingly small: 4–5% for the Thomas method and 2–3% for the Kusnetz method. Now, I can correct uncertainty values of radon progeny measurements if it is appropriate to do so. The detailed calculations I present here may be used for determining corrections to the counting uncertainty for a method for measuring radon progeny concentration using different sampling and/or counting times than those described here. Further, they may be used for any sample, not necessarily radon progeny, that requires a long counting time to acquire a significant number of observed counts.
PubDate: Mon, 15 Apr 2024 00:00:00 GMT-
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- Neutron Activation Analysis Based on AB-BNCT Treatment Room
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Authors: Cai; Yunzhu; Gu, Shaoxian; Wang, Ningyu; Cui, Fengjie; Liu, Wei; Li, Tianhang; Wu, Zhangwen; Gou, Chengjun
Abstract:
Boron neutron capture therapy (BNCT) is an ideal binary targeted radiotherapy for treating refractory tumors. An accelerator-based BNCT (AB-BNCT) neutron source has attracted more and more attention due to its advantages such as higher neutron yield in the keV energy region, less gamma radiation, and higher safety. In addition to 10B, neutrons also react with other elements in the treatment room during BNCT to produce many activation products. Due to the long half-life of some activation products, there will be residual radiation after the end of treatment and the shutdown of the accelerator, which has adverse effects on radiation workers. Therefore, the ambient dose equivalent rate in the treatment room needs to be evaluated. The AB-BNCT neutron source model proposed by Li is studied in this paper. Based on the Monte Carlo method, the Geant4 platform was used to simulate the dose induced by radionuclides near the Beam Shaping Assembly (BSA) of the source. It is concluded that the concrete wall contributed the most to the radiation dose. The dose rate of 2.45 μSv h−1 after 13 min of shutdown meets the dose rate limit of 2.5 μSv h−1, at which point it is safe for workers to enter the treatment room area.
PubDate: Mon, 15 Apr 2024 00:00:00 GMT-
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- Feasibility of Liver Transplantation after 90Y Radioembolization: Lessons
from a Radiation Protection Incident-
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Authors: Soret; Marine; Maisonobe, Jacques-Antoine; Maksud, Philippe; Payen, Stéphane; Allaire, Manon; Savier, Eric; Roux, Charles; Lussey-Lepoutre, Charlotte; Kas, Aurélie
Abstract:
Radioembolization using 90Y is a growing procedure in nuclear medicine for treating hepatocellular carcinoma. Current guidelines suggest postponing liver transplantation or surgical resection for a period of 14 to 30 d after radioembolization to minimize surgeons’ exposure to ionizing radiation. In light of a radiation protection incident, we reevaluated the minimum delay required between radioembolization and subsequent liver transplantation. A patient with a hepatocellular carcinoma underwent a liver transplantation 44 h after undergoing radioembolization using 90Y (860 MBq SIR-Spheres). No specific radioprotection measures were followed during surgery and pathological analysis. We subsequently (1) evaluated the healthcare professionals' exposure to ionizing radiation by conducting dose rate measurements from removed liver tissue and (2) extrapolated the recommended interval to be observed between radioembolization and surgery/transplantation to ensure compliance with the radiation dose limits for worker safety. The surgeons involved in the transplantation procedure experienced the highest radiation exposure, with whole-body doses of 2.4 mSv and extremity doses of 24 mSv. The recommended delay between radioembolization and liver transplantation was 8 d when using SIR-Spheres and 15 d when injecting TheraSphere. This delay can be reduced further when considering the specific 90Y activity administered during radioembolization. This dosimetric study suggests the feasibility of shortening the delay for liver transplantation/surgery after radioembolization from the 8th or 15th day after using SIR-Spheres or TheraSphere, respectively. This delay can be decreased further when adjusted to the administrated activity while upholding radiation protection standards for healthcare professionals.
PubDate: Tue, 26 Mar 2024 00:00:00 GMT-
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- Feasibility of Treatment Agents in Radioactive Iodine Separation from
Waste Liquids-
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Authors: Hirota; Masahiro; Higaki, Shogo; Ishida, Yoshiyuki; Nakata, Daisuke; Terao, Keiji; Ito, Shigeki
Abstract:
To discharge waste liquid containing radioactive iodine into sewage systems, long-term storage or dilution with a large amount of water may be required until the radioactivity concentration reduces below the standard value. Processing the waste liquid could be easier if radioactive iodine could be separated from the water. This study verified the effectiveness of superabsorbent polymer and α-cyclodextrin as treatment agents to separate radioactive iodine from waste liquids. Sodium iodide (Na125I) was added to purified water and artificial urine to prepare simulated waste liquids containing iodine equivalent to the urine of patients treated with radioactive iodine. The as-prepared simulated waste liquid was poured into a container with superabsorbent polymer and left for 90 d. The residual iodine rate in the simulated waste liquid was estimated by measuring 125I radioactivity. When the water was sufficiently dried, residual iodine rates on day 15 were 0.102 and 0.884 in the simulated waste liquids comprising purified water and artificial urine, respectively. The simulated waste liquid comprising purified water with 5% α-cyclodextrin absorbed by 1 g of superabsorbent polymer had a residual rate of 0.980. Moreover, the residual rate of simulated waste liquid comprising artificial urine with 2% α-cyclodextrin absorbed by 1 g of SAP was 0.949. Superabsorbent polymer combined with α-cyclodextrin was an effective treatment agent for separating radioactive iodine from waste liquids.
PubDate: Wed, 10 Jan 2024 00:00:00 GMT-
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