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Lochard J, Bartlett DT, Rühm W, Yasuda H, Bottollier-Depois JF. ICRP Publication 132: Radiological Protection from Cosmic Radiation in Aviation. Ann ICRP 2017; 45:5-48. [PMID: 27279360 DOI: 10.1177/0146645316645449] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract – In this publication, the International Commission on Radiological
Protection (ICRP) provides updated guidance on radiological protection from
cosmic radiation in aviation, taking into account the current ICRP system of radiological
protection, the latest available data on exposures in aviation, and experience
gained worldwide in the management of exposures in aviation. The publication
describes the origins of cosmic radiation, how it exposes passengers and aircraft
crew, the basic radiological protection principles that apply to this existing exposure
situation, and the available protective actions. For implementation of the optimisation
principle, the Commission recommends a graded approach proportionate to the
level of exposure that may be received by individuals. The objective is to keep the
exposure of the most exposed individuals to a reasonable level. The Commission also
recommends that information be disseminated to raise awareness about cosmic radiation,
and to support informed decisions among concerned stakeholders.
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El-Kameesy SU, Salama E, El-Fiki SA, Ehab M, Rühm W. Radiological safety assessment inside ancient Egyptian tombs in Saqqara. ISOTOPES IN ENVIRONMENTAL AND HEALTH STUDIES 2016; 52:567-576. [PMID: 26988604 DOI: 10.1080/10256016.2016.1142444] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2015] [Accepted: 11/10/2015] [Indexed: 06/05/2023]
Abstract
Many archaeological sites in Egypt are unique worldwide, such as ancient tombs and pyramids, because they document fundamental developments in human civilization that took place several thousands of years ago. For this reason, these sites are visited by numerous visitors every year. The present work is devoted to provide a pre-operational radiological baseline needed to quantify occupational radiation exposure at the famous Saqqara region in Cairo, Egypt. A hyperpure Ge detector has been used in the γ-ray spectrometric analysis while the (222)Rn concentration was measured using a portable radon monitor RTM 1688-2, SARAD. The mean specific activities of (226)Ra, (232)Th and (40)K in the samples collected from the interior walls of the Saqqara tombs were determined and found to show average values of 16, 8.5 and 45 Bq kg(-1), respectively. The concentration of radon was measured inside the tombs Serapeum, South tomb and the Zoser Pyramid (fifth level) and an associated average working level of 0.83 WL was obtained. In order to avoid the health hazards associated with the exposure to radon during the long period of work inside these tombs, proposed solutions are introduced.
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Giussani A, Nogueira P, El Faramawy N, Buchholz W, Gerstmann UC, Hartmann M, Meisenberg O, Noßke D, Rühm W. A puzzling case of contamination with 241Am. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2016; 36:391-404. [PMID: 27340035 DOI: 10.1088/0952-4746/36/3/391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Two people were exposed to and contaminated with 241Am. In vivo determinations of the incorporated 241Am were performed using a whole-body counter and two partial-body counters for the skull and lung, respectively. Additionally, urine samples were analysed to estimate the systemic activity removed from the body. To improve the geometry of the skull measurements, an optimised detector configuration was used, a calibration with three physical phantoms of the human head was conducted, and the morphological variability between the individuals was also considered. The results of the measurements indicate that activity is not deposited in the deep tissues, rather in the skin tissues close to the body surface. Unfortunately, the many open questions relating to the actual circumstances during and after the incident make the interpretation of this case difficult if at all possible.
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Müller WU, Giussani A, Rühm W, Lecomte JF, Harrison J, Kreuzer M, Sobotzki C, Breckow J. Current knowledge on radon risk: implications for practical radiation protection? radon workshop, 1/2 December 2015, Bonn, BMUB (Bundesministerium für Umwelt, Naturschutz, Bau und Reaktorsicherheit; Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety). RADIATION AND ENVIRONMENTAL BIOPHYSICS 2016; 55:267-80. [PMID: 27334644 PMCID: PMC4951500 DOI: 10.1007/s00411-016-0657-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2016] [Accepted: 05/31/2016] [Indexed: 05/03/2023]
Abstract
ICRP suggested a strategy based on the distinction between a protection approach for dwellings and one for workplaces in the previous recommendations on radon. Now, the Commission recommends an integrated approach for the protection against radon exposure in all buildings irrespective of their purpose and the status of their occupants. The strategy of protection in buildings, implemented through a national action plan, is based on the application of the optimisation principle below a derived reference level in concentration (maximum 300 Bq m(-3)). A problem, however, arises that due to new epidemiological findings and application of dosimetric models, ICRP 115 (Ann ICRP 40, 2010) presents nominal probability coefficients for radon exposure that are approximately by a factor of 2 larger than in the former recommendations of ICRP 65 (Ann ICRP 23, 1993). On the basis of the so-called epidemiological approach and the dosimetric approach, the doubling of risk per unit exposure is represented by a doubling of the dose coefficients, while the risk coefficient of ICRP 103 (2007) remains unchanged. Thus, an identical given radon exposure situation with the new dose coefficients would result in a doubling of dose compared with the former values. This is of serious conceptual implications. A possible solution of this problem was presented during the workshop.
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Irlinger J, Trinkl S, Wielunksi M, Tschiersch J, Rühm W. Monte Carlo simulation of semiconductor detector response to (222)Rn and (220)Rn environments. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2016; 158-159:64-70. [PMID: 27074199 DOI: 10.1016/j.jenvrad.2016.03.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Revised: 03/29/2016] [Accepted: 03/30/2016] [Indexed: 06/05/2023]
Abstract
A new electronic radon/thoron monitor employing semiconductor detectors based on a passive diffusion chamber design has been recently developed at the Helmholtz Zentrum München (HMGU). This device allows for acquisition of alpha particle energy spectra, in order to distinguish alpha particles originating from radon and radon progeny decays, as well as those originating from thoron and its progeny decays. A Monte-Carlo application is described which uses the Geant4 toolkit to simulate these alpha particle spectra. Reasonable agreement between measured and simulated spectra were obtained for both (220)Rn and (222)Rn, in the energy range between 1 and 10 MeV. Measured calibration factors could be reproduced by the simulation, given the uncertainties involved in the measurement and simulation. The simulated alpha particle spectra can now be used to interpret spectra measured in mixed radon/thoron atmospheres. The results agreed well with measurements performed in both radon and thoron gas environments. It is concluded that the developed simulation allows for an accurate prediction of calibration factors and alpha particle energy spectra.
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Rühm W, Azizova TV, Bouffler SD, Little MP, Shore RE, Walsh L, Woloschak GE. Dose-rate effects in radiation biology and radiation protection. Ann ICRP 2016; 45:262-279. [PMID: 26960819 DOI: 10.1177/0146645316629336] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Quantification of biological effects (cancer, other diseases, and cell damage) associated with exposure to ionising radiation has been a major issue for the International Commission on Radiological Protection (ICRP) since its foundation in 1928. While there is a wealth of information on the effects on human health for whole-body doses above approximately 100 mGy, the effects associated with doses below 100 mGy are still being investigated and debated intensively. The current radiological protection approach, proposed by ICRP for workers and the public, is largely based on risks obtained from high-dose and high-dose-rate studies, such as the Japanese Life Span Study on atomic bomb survivors. The risk coefficients obtained from these studies can be reduced by the dose and dose-rate effectiveness factor (DDREF) to account for the assumed lower effectiveness of low-dose and low-dose-rate exposures. The 2007 ICRP Recommendations continue to propose a value of 2 for DDREF, while other international organisations suggest either application of different values or abandonment of the factor. This paper summarises the current status of discussions, and highlights issues that are relevant to reassessing the magnitude and application of DDREF.
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Blettner M, Jacob P, Rühm W, Salomaa S. Obituary William F. Morgan (23 December 1952--13 November 2015). RADIATION AND ENVIRONMENTAL BIOPHYSICS 2016; 55:1-2. [PMID: 26715105 DOI: 10.1007/s00411-015-0632-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2015] [Accepted: 12/14/2015] [Indexed: 06/05/2023]
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Rühm W, Fantuzzi E, Harrison R, Schuhmacher H, Vanhavere F, Alves J, Bottollier Depois JF, Fattibene P, Knežević Ž, Lopez MA, Mayer S, Miljanić S, Neumaier S, Olko P, Stadtmann H, Tanner R, Woda C. EURADOS strategic research agenda: vision for dosimetry of ionising radiation. RADIATION PROTECTION DOSIMETRY 2016; 168:223-34. [PMID: 25752758 PMCID: PMC4884873 DOI: 10.1093/rpd/ncv018] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 02/05/2015] [Accepted: 02/06/2015] [Indexed: 05/04/2023]
Abstract
Since autumn 2012, the European Radiation Dosimetry Group (EURADOS) has been developing its Strategic Research Agenda (SRA), which is intended to contribute to the identification of future research needs in radiation dosimetry in Europe. The present article summarises-based on input from EURADOS Working Groups (WGs) and Voting Members-five visions in dosimetry and defines key issues in dosimetry research that are considered important for the next decades. The five visions include scientific developments required towards (a) updated fundamental dose concepts and quantities, (b) improved radiation risk estimates deduced from epidemiological cohorts, (c) efficient dose assessment for radiological emergencies, (d) integrated personalised dosimetry in medical applications and (e) improved radiation protection of workers and the public. The SRA of EURADOS will be used as a guideline for future activities of the EURADOS WGs. A detailed version of the SRA can be downloaded as a EURADOS report from the EURADOS website (www.eurados.org).
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Rühm W, Woloschak GE, Shore RE, Azizova TV, Grosche B, Niwa O, Akiba S, Ono T, Suzuki K, Iwasaki T, Ban N, Kai M, Clement CH, Bouffler S, Toma H, Hamada N. Dose and dose-rate effects of ionizing radiation: a discussion in the light of radiological protection. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2015; 54:379-401. [PMID: 26343037 DOI: 10.1007/s00411-015-0613-6] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Accepted: 08/18/2015] [Indexed: 05/21/2023]
Abstract
The biological effects on humans of low-dose and low-dose-rate exposures to ionizing radiation have always been of major interest. The most recent concept as suggested by the International Commission on Radiological Protection (ICRP) is to extrapolate existing epidemiological data at high doses and dose rates down to low doses and low dose rates relevant to radiological protection, using the so-called dose and dose-rate effectiveness factor (DDREF). The present paper summarizes what was presented and discussed by experts from ICRP and Japan at a dedicated workshop on this topic held in May 2015 in Kyoto, Japan. This paper describes the historical development of the DDREF concept in light of emerging scientific evidence on dose and dose-rate effects, summarizes the conclusions recently drawn by a number of international organizations (e.g., BEIR VII, ICRP, SSK, UNSCEAR, and WHO), mentions current scientific efforts to obtain more data on low-dose and low-dose-rate effects at molecular, cellular, animal and human levels, and discusses future options that could be useful to improve and optimize the DDREF concept for the purpose of radiological protection.
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Nogueira P, Rühm W, Lopez M, Vrba T, Buchholz W, Fojtík P, Etherington G, Broggio D, Huikari J, Marzocchi O, Lynch T, Lebacq A, Li C, Ośko J, Malátova I, Franck D, Breustedt B, Leone D, Scott J, Shutt A, Hauck B, Capello K, Pérez-López B, Navarro-Amaro J, Pliszczyński T, Fantínová K, Tolmachev S. EURADOS 241Am skull measurement intercomparison. RADIAT MEAS 2015. [DOI: 10.1016/j.radmeas.2015.07.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Träber SC, Li WB, Höllriegl V, Nebelung K, Michalke B, Rühm W, Oeh U. Calculation of internal dose from ingested soil-derived uranium in humans: Application of a new method. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2015; 54:265-272. [PMID: 25980738 DOI: 10.1007/s00411-015-0602-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Accepted: 04/28/2015] [Indexed: 06/04/2023]
Abstract
The aim of the present study was to determine the internal dose in humans after the ingestion of soil highly contaminated with uranium. Therefore, an in vitro solubility assay was performed to estimate the bioaccessibility of uranium for two types of soil. Based on the results, the corresponding bioavailabilities were assessed by using a recently published method. Finally, these bioavailability data were used together with the biokinetic model of uranium to assess the internal doses for a hypothetical but realistic scenario characterized by a daily ingestion of 10 mg of soil over 1 year. The investigated soil samples were from two former uranium mining sites of Germany with (238)U concentrations of about 460 and 550 mg/kg. For these soils, the bioavailabilities of (238)U were quantified as 0.18 and 0.28 % (geometric mean) with 2.5th percentiles of 0.02 and 0.03 % and 97.5th percentiles of 1.48 and 2.34 %, respectively. The corresponding calculated annual committed effective doses for the assumed scenario were 0.4 and 0.6 µSv (GM) with 2.5th percentiles of 0.2 and 0.3 µSv and 97.5th percentiles of 1.6 and 3.0 µSv, respectively. These annual committed effective doses are similar to those from natural uranium intake by food and drinking water, which is estimated to be 0.5 µSv. Based on the present experimental data and the selected ingestion scenario, the investigated soils-although highly contaminated with uranium-are not expected to pose any major health risk to humans related to radiation.
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Alves J, Bottollier-Depois JF, Fantuzzi E, Fattibene P, Lopez MA, Mayer S, Miljanić S, Olko P, Rühm W, Schuhmacher H, Stadtmann H, Vanhavere F. Letter to the editor. RADIATION PROTECTION DOSIMETRY 2015; 163:268. [PMID: 24854851 DOI: 10.1093/rpd/ncu160] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
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Träber SC, Höllriegl V, Li WB, Czeslik U, Rühm W, Oeh U, Michalke B. Estimating the absorption of soil-derived uranium in humans. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:14721-14727. [PMID: 25417915 DOI: 10.1021/es504171r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The aim of the present study was to improve the estimation of soil-derived uranium absorption in humans. For this purpose, an in vitro solubility assay was combined with a human study by using a specific edible soil low in uranium. The mean bioaccessibility of the soil-derived uranium, determined by the solubility assay in artificial gastrointestinal fluid, was found to be 7.7% with a standard deviation of 0.2%. The corresponding bioavailability of the soil-derived uranium in humans was assumed to be log-normal distributed with a geometric mean of 0.04% and a 95% confidence interval ranging from 0.0049% to 0.34%. Both results were used to calculate a factor, denoted as fA(sol), which describes the relation between the bioaccessibility and the bioavailability of soil-derived uranium. The geometric mean of fA(sol) was determined to be 0.53% with a 95% confidence interval ranging from 0.06% to 4.43%. Based on fA(sol), it is possible to estimate more realistic values on the bioavailability of uranium for highly uranium-contaminated soils in humans by just performing the applied solubility assay. The results of this study can be further used to obtain more reliable results on the internal dose assessment of ingested highly uranium-contaminated soils.
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Aerts AM, Impens NREN, Baatout S, Benotmane MA, Camps J, Dabin JM, Derradji H, Grosche B, Horemans N, Jourdain JR, Moreels M, Perko T, Quintens R, Repussard J, Rühm W, Schneider T, Struelens L, Hardeman F. Joint research towards a better radiation protection-highlights of the Fifth MELODI Workshop. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2014; 34:931-56. [PMID: 25431966 DOI: 10.1088/0952-4746/34/4/931] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
MELODI is the European platform dedicated to low-dose radiation risk research. From 7 October through 10 October 2013 the Fifth MELODI Workshop took place in Brussels, Belgium. The workshop offered the opportunity to 221 unique participants originating from 22 countries worldwide to update their knowledge and discuss radiation research issues through 118 oral and 44 poster presentations. In addition, the MELODI 2013 workshop was reaching out to the broader radiation protection community, rather than only the low-dose community, with contributions from the fields of radioecology, emergency and recovery preparedness, and dosimetry. In this review, we summarise the major scientific conclusions of the workshop, which are important to keep the MELODI strategic research agenda up-to-date and which will serve to establish a joint radiation protection research roadmap for the future.
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Barros S, Mares V, Bedogni R, Reginatto M, Esposito A, F Gonçalves I, Vaz P, Rühm W. Comparison of unfolding codes for neutron spectrometry with Bonner spheres. RADIATION PROTECTION DOSIMETRY 2014; 161:46-52. [PMID: 24442664 DOI: 10.1093/rpd/nct353] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
This work compares the results of four different unfolding codes, MSANDB, MAXED, FRUIT and BONMA, which are based on different unfolding techniques. Additionally, Bayesian parameter estimation is also considered. All unfolding codes were supplied with the same set of input data acquired at the Environmental Research Station 'Schneefernerhaus' on the Zugspitze mountain, corresponding to continuous measurements of secondary neutrons from cosmic radiation. The HMGU high-energy extended Bonner sphere spectrometer (BSS), consisting of 16 measuring channels with (3)He proportional counters, was used as a reference BSS. The differences in the neutron spectra obtained with the different unfolding codes are discussed, and the uncertainties of integral quantities, like neutron fluence and ambient dose equivalent, are quantified.
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Bergmeier F, Volnhals M, Wielunski M, Rühm W. Simulation and calibration of an active neutron dosemeter. RADIATION PROTECTION DOSIMETRY 2014; 161:126-129. [PMID: 24368869 DOI: 10.1093/rpd/nct316] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Here the latest development stages of the HMGU active neutron dosemeter are presented. This work includes the comparison of the dosemeter's response function, calculated with Geant4, and the measurements in monoenergetic neutron fields at the Physikalisch Technische Bundesanstalt in Braunschweig, Germany. These results were used to match the response function and the count-to-dose conversion factors of the dosemeter to the Hp(10) personal dose equivalent.
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Rühm W, Mares V, Pioch C, Agosteo S, Endo A, Ferrarini M, Rakhno I, Rollet S, Satoh D, Vincke H. Comparison of Bonner sphere responses calculated by different Monte Carlo codes at energies between 1 MeV and 1 GeV – Potential impact on neutron dosimetry at energies higher than 20 MeV. RADIAT MEAS 2014. [DOI: 10.1016/j.radmeas.2014.05.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Irlinger J, Wielunski M, Rühm W. Thoron detection with an active Radon exposure meter--first results. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:022106. [PMID: 24593342 DOI: 10.1063/1.4865162] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
For state-of-the-art discrimination of Radon and Thoron several measurement techniques can be used, such as active sampling, electrostatic collection, delayed coincidence method, and alpha-particle-spectroscopy. However, most of the devices available are bulky and show high power consumption, rendering them unfeasible for personal exposition monitoring. Based on a Radon exposure meter previously realized at the Helmholtz Center Munich (HMGU), a new electronic prototype for Radon/Thoron monitoring is currently being developed, which features small size and weight. Operating with pin-diode detectors, the low-power passive-sampling device can be used for continuous concentration measurements, employing alpha-particle-spectroscopy and coincidence event registration to distinguish decays originating either from Radon or Thoron isotopes and their decay products. In open geometry, preliminary calibration measurements suggest that one count per hour is produced by a 11 Bq m(-3) Radon atmosphere or by a 15 Bq m(-3) Thoron atmosphere. Future efforts will concentrate on measurements in mixed Radon/Thoron atmospheres.
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Friedl AA, Rühm W. 50 years of Radiation and Environmental Biophysics: what were the hallmark papers? RADIATION AND ENVIRONMENTAL BIOPHYSICS 2013; 52:171-174. [PMID: 23532414 DOI: 10.1007/s00411-013-0466-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Accepted: 03/11/2013] [Indexed: 06/02/2023]
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Rühm W, Friedl AA. Fifty years ago …. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2013; 52:1-3. [PMID: 23306442 DOI: 10.1007/s00411-012-0455-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Accepted: 12/27/2012] [Indexed: 06/01/2023]
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Garny S, Rühm W, Zankl M, Wagner FM, Paretzke HG. First steps towards a fast-neutron therapy planning program. Radiat Oncol 2011; 6:163. [PMID: 22118299 PMCID: PMC3261826 DOI: 10.1186/1748-717x-6-163] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Accepted: 11/25/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The Monte Carlo code GEANT4 was used to implement first steps towards a treatment planning program for fast-neutron therapy at the FRM II research reactor in Garching, Germany. Depth dose curves were calculated inside a water phantom using measured primary neutron and simulated primary photon spectra and compared with depth dose curves measured earlier. The calculations were performed with GEANT4 in two different ways, simulating a simple box geometry and splitting this box into millions of small voxels (this was done to validate the voxelisation procedure that was also used to voxelise the human body). RESULTS In both cases, the dose distributions were very similar to those measured in the water phantom, up to a depth of 30 cm. In order to model the situation of patients treated at the FRM II MEDAPP therapy beamline for salivary gland tumors, a human voxel phantom was implemented in GEANT4 and irradiated with the implemented MEDAPP neutron and photon spectra. The 3D dose distribution calculated inside the head of the phantom was similar to the depth dose curves in the water phantom, with some differences that are explained by differences in elementary composition. The lateral dose distribution was studied at various depths. The calculated cumulative dose volume histograms for the voxel phantom show the exposure of organs at risk surrounding the tumor. CONCLUSIONS In order to minimize the dose to healthy tissue, a conformal treatment is necessary. This can only be accomplished with the help of an advanced treatment planning system like the one developed here. Although all calculations were done for absorbed dose only, any biological dose weighting can be implemented easily, to take into account the increased radiobiological effectiveness of neutrons compared to photons.
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Kramer GH, Hauck B, Capello K, Rühm W, El-Faramawy N, Broggio D, Franck D, Lopez MA, Navarro T, Navarro JF, Perez B, Tolmachev S. Comparison of two leg phantoms containing (241)Am in bone. HEALTH PHYSICS 2011; 101:248-258. [PMID: 21799341 DOI: 10.1097/hp.0b013e3182118f61] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Three facilities (CIEMAT, HMGU and HML) have used their in vivo counters to compare two leg phantoms. One was commercially produced with (241)Am activity artificially added to the bone inserts. The other, the United States Transuranium and Uranium Registries' (USTUR) leg phantom, was manufactured from (241)Am-contaminated bones resulting from an intake. The comparison of the two types of leg phantoms showed that the two phantoms are not similar in their activity distributions. An error in a bone activity estimate could be quite large if the commercial leg phantom is used to estimate what is contained in the USTUR leg phantom and, consequently, a real person. As the latter phantom was created as a result of a real contamination, it is deemed to be the more representative of what would actually happen if a person were internally contaminated with (241)Am.
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Takamiya K, Imanaka T, Egbert SD, Rühm W. Amendments to (63)Ni production calculation for Hiroshima by Takamiya et al. and DS02 fluence data by Egbert et al. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2011; 50:329-333. [PMID: 21327808 DOI: 10.1007/s00411-011-0356-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Accepted: 01/29/2011] [Indexed: 05/30/2023]
Abstract
In a previous paper, Takamiya et al. calculated (63)Ni production in copper samples exposed to the Hiroshima atomic bomb. More specifically, they used their experimental cross-section values of the (63)Cu(n,p)(63)Ni reaction and compared the result with that of the corresponding calculation in the radiation dosimetry system DS02, which used another set of cross-section values. These results were different, and the following two reasons were found: typographical errors in several energy boundary values in the DS02 report that was also used in the calculation by Takamiya et al. and an inappropriate assumption on the cross-section values of the low neutron energy region in the calculation by Takamiya et al. These two issues are described and amended in the present report.
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Gruber E, Salama E, Rühm W. Real-time measurement of individual occupational radon exposures in tombs of the Valley of the Kings, Egypt. RADIATION PROTECTION DOSIMETRY 2011; 144:620-626. [PMID: 21183552 DOI: 10.1093/rpd/ncq450] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The active radon exposure meter developed recently at the German Research Center for Environmental Health (Helmholtz Zentrum München) was used to measure radon concentrations in 12 tombs located in the Valley of the Kings, Egypt. Radon concentrations in air between 50 ± 7 and 12 100 ± 600 Bq m(-3) were obtained. The device was also used to measure individual radon exposures of those persons working as safeguards inside the tombs. For a measurement time of 2-3 d, typical individual radon exposures ranged from 1800 ± 400 to 240 000 ± 13 000 Bq h m(-3), depending on the duration of measurement and radon concentration in the different tombs. Based on current ICRP dose conversion conventions for workers and on equilibrium factors published in the literature for these tombs, individual effective dose rates that range from 1.5 ± 0.3 to 860 ± 50 µSv d(-1) were estimated. If it is assumed that the climatic conditions present at the measurement campaign persist for about half a year, in this area, then effective doses up to ∼ 66 mSv could be estimated for half a year, for some of the safeguards of tombs where F-values were known. To reduce the exposure of the safeguards, some recommendations are proposed.
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Lopez MA, Broggio D, Capello K, Cardenas-Mendez E, El-Faramawy N, Franck D, James AC, Kramer GH, Lacerenza G, Lynch TP, Navarro JF, Navarro T, Perez B, Rühm W, Tolmachev SY, Weitzenegger E. EURADOS intercomparison on measurements and Monte Carlo modelling for the assessment of americium in a USTUR leg phantom. RADIATION PROTECTION DOSIMETRY 2011; 144:295-299. [PMID: 21076141 DOI: 10.1093/rpd/ncq304] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A collaboration of the EURADOS working group on 'Internal Dosimetry' and the United States Transuranium and Uranium Registries (USTUR) has taken place to carry out an intercomparison on measurements and Monte Carlo modelling determining americium deposited in the bone of a USTUR leg phantom. Preliminary results and conclusions of this intercomparison exercise are presented here.
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