Science.gov

Sample records for radiation accident dosimetry

  1. An EPR dosimetry method for rapid scanning of children following a radiation accident using deciduous teeth

    SciTech Connect

    Haskell, E.H.; Hayes, R.B.; Kenner, G.H.

    1999-02-01

    Electron paramagnetic resonance dosimetry may be applied to whole deciduous teeth of children. This makes it feasible to make direct measurement of absorbed gamma ray dose in the days and weeks following a nuclear accident, particularly if used in conjunction with a public awareness program. The technique reported here requires little sample preparation and has resulted in precision of approximately 30 mGy (1 {sigma}) for a deciduous incisor. Under conditions for rapid screening procedures, the methodology is estimated to provide 0.5 Gy accuracy. The largest error in the process is the determination of an appropriate background native signal for subtraction from the whole tooth spectrum. The native signal is superimposed on the radiation-induced signal, and the subtraction requires knowledge of a sample`s relative content of enamel and dentin along with their relative native signal intensities. Using a composite background standard, an equivalent absorbed dose of 70 {+-} 38 mGy (1 {sigma}) was determined. The lower detection limit of the technique was achieved by the elimination of anisotropic effects through rotation of the sample during measurement, together with subtraction of the standard native background signal and empty tube background spectra from the sample spectra.

  2. Personal nuclear accident dosimetry at Sandia National Laboratories

    SciTech Connect

    Ward, D.C.; Mohagheghi, A.H.; Burrows, R.

    1996-09-01

    DOE installations possessing sufficient quantities of fissile material to potentially constitute a critical mass, such that the excessive exposure of personnel to radiation from a nuclear accident is possible, are required to provide nuclear accident dosimetry services. This document describes the personal nuclear accident dosimeter (PNAD) used by SNL and prescribes methodologies to initially screen, and to process PNAD results. In addition, this report describes PNAD dosimetry results obtained during the Nuclear Accident Dosimeter Intercomparison Study (NAD23), held during 12-16 June 1995, at Los Alamos National Laboratories. Biases for reported neutron doses ranged from -6% to +36% with an average bias of +12%.

  3. Radiation accidents

    SciTech Connect

    Saenger, E.L.

    1986-09-01

    It is essential that emergency physicians understand ways to manage patients contaminated by radioactive materials and/or exposed to external radiation sources. Contamination accidents require careful surveys to identify the metabolic pathway of the radionuclides to guide prognosis and treatment. The level of treatment required will depend on careful surveys and meticulous decontamination. There is no specific therapy for the acute radiation syndrome. Prophylactic antibodies are desirable. For severely exposed patients treatment is similar to the supportive care given to patients undergoing organ transplantation. For high-dose extremity injury, no methods have been developed to reverse the fibrosing endarteritis that eventually leads to tissue death so frequently found with this type of injury. Although the Three Mile Island episode of March 1979 created tremendous public concern, there were no radiation injuries. The contamination outside the reactor building and the release of radioiodine were negligible. The accidental fuel element meltdown at Chernobyl, USSR, resulted in many cases of acute radiation syndrome. More than 100,000 people were exposed to high levels of radioactive fallout. The general principles outlined here are applicable to accidents of that degree of severity.

  4. Radiation accidents.

    PubMed

    Saenger, E L

    1986-09-01

    It is essential that emergency physicians understand ways to manage patients contaminated by radioactive materials and/or exposed to external radiation sources. Contamination accidents require careful surveys to identify the metabolic pathway of the radionuclides to guide prognosis and treatment. The level of treatment required will depend on careful surveys and meticulous decontamination. There is no specific therapy for the acute radiation syndrome. Prophylactic antibodies are desirable. For severely exposed patients treatment is similar to the supportive care given to patients undergoing organ transplantation. For high-dose extremity injury, no methods have been developed to reverse the fibrosing endarteritis that eventually leads to tissue death so frequently found with this type of injury. Although the Three Mile Island episode of March 1979 created tremendous public concern, there were no radiation injuries. The contamination outside the reactor building and the release of radioiodine were negligible. The accidental fuel element meltdown at Chernobyl, USSR, resulted in many cases of acute radiation syndrome. More than 100,000 people were exposed to high levels of radioactive fallout. The general principles outlined here are applicable to accidents of that degree of severity. PMID:3526994

  5. Dosimetry for radiation processing

    NASA Astrophysics Data System (ADS)

    Miller, Arne

    During the past few years significant advances have taken place in the different areas of dosimetry for radiation processing, mainly stimulated by the increased interest in radiation for food preservation, plastic processing and sterilization of medical products. Reference services both by international organizations (IAEA) and national laboratories have helped to improve the reliability of dose measurements. Several dosimeter systems like calorimetry, perspex, and radiochromic dye films are being improved and new systems have emerged, e.g. spectrophotometry of dichromate solution for reference and sterilization dosimetry, optichromic dosimeters in the shape of small tubes for food processing, and ESR spectroscopy of alanine for reference dosimetry. In this paper the special features of radiation processing dosimetry are discussed, several commonly used dosimeters are reviewed, and factors leading to traceable and reliable dosimetry are discussed.

  6. 10 CFR 835.1304 - Nuclear accident dosimetry.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Nuclear accident dosimetry. 835.1304 Section 835.1304... Nuclear accident dosimetry. (a) Installations possessing sufficient quantities of fissile material to... nuclear accident is possible, shall provide nuclear accident dosimetry for those individuals. (b)...

  7. 10 CFR 835.1304 - Nuclear accident dosimetry.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Nuclear accident dosimetry. 835.1304 Section 835.1304... Nuclear accident dosimetry. (a) Installations possessing sufficient quantities of fissile material to... nuclear accident is possible, shall provide nuclear accident dosimetry for those individuals. (b)...

  8. 10 CFR 835.1304 - Nuclear accident dosimetry.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Nuclear accident dosimetry. 835.1304 Section 835.1304... Nuclear accident dosimetry. (a) Installations possessing sufficient quantities of fissile material to... nuclear accident is possible, shall provide nuclear accident dosimetry for those individuals. (b)...

  9. 10 CFR 835.1304 - Nuclear accident dosimetry.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Nuclear accident dosimetry. 835.1304 Section 835.1304... Nuclear accident dosimetry. (a) Installations possessing sufficient quantities of fissile material to... nuclear accident is possible, shall provide nuclear accident dosimetry for those individuals. (b)...

  10. 10 CFR 835.1304 - Nuclear accident dosimetry.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Nuclear accident dosimetry. 835.1304 Section 835.1304... Nuclear accident dosimetry. (a) Installations possessing sufficient quantities of fissile material to... nuclear accident is possible, shall provide nuclear accident dosimetry for those individuals. (b)...

  11. Fundamentals of Radiation Dosimetry

    NASA Astrophysics Data System (ADS)

    Bos, Adrie J. J.

    2011-05-01

    The basic concepts of radiation dosimetry are reviewed on basis of ICRU reports and text books. The radiation field is described with, among others, the particle fluence. Cross sections for indirectly ionizing radiation are defined and indicated is how they are related to the mass energy transfer and mass energy absorption coefficients. Definitions of total and restricted mass stopping powers of directly ionizing radiation are given. The dosimetric quantities, kerma, absorbed dose and exposure together with the relations between them are discussed in depth. Finally it is indicated how the absorbed dose can be measured with a calorimeter by measuring the temperature increase and with an ionisation chamber measuring the charge produced by the ionizing radiation and making use of the Bragg-Gray relation.

  12. Fundamentals of Radiation Dosimetry

    SciTech Connect

    Bos, Adrie J. J.

    2011-05-05

    The basic concepts of radiation dosimetry are reviewed on basis of ICRU reports and text books. The radiation field is described with, among others, the particle fluence. Cross sections for indirectly ionizing radiation are defined and indicated is how they are related to the mass energy transfer and mass energy absorption coefficients. Definitions of total and restricted mass stopping powers of directly ionizing radiation are given. The dosimetric quantities, kerma, absorbed dose and exposure together with the relations between them are discussed in depth. Finally it is indicated how the absorbed dose can be measured with a calorimeter by measuring the temperature increase and with an ionisation chamber measuring the charge produced by the ionizing radiation and making use of the Bragg-Gray relation.

  13. Reconstructive dosimetry for cutaneous radiation syndrome

    PubMed Central

    Lima, C.M.A.; Lima, A.R.; Degenhardt, Ä.L.; Valverde, N.J.; Da Silva, F.C.A.

    2015-01-01

    According to the International Atomic Energy Agency (IAEA), a relatively significant number of radiological accidents have occurred in recent years mainly because of the practices referred to as potentially high-risk activities, such as radiotherapy, large irradiators and industrial radiography, especially in gammagraphy assays. In some instances, severe injuries have occurred in exposed persons due to high radiation doses. In industrial radiography, 80 cases involving a total of 120 radiation workers, 110 members of the public including 12 deaths have been recorded up to 2014. Radiological accidents in industrial practices in Brazil have mainly resulted in development of cutaneous radiation syndrome (CRS) in hands and fingers. Brazilian data include 5 serious cases related to industrial gammagraphy, affecting 7 radiation workers and 19 members of the public; however, none of them were fatal. Some methods of reconstructive dosimetry have been used to estimate the radiation dose to assist in prescribing medical treatment. The type and development of cutaneous manifestations in the exposed areas of a person is the first achievable gross dose estimation. This review article presents the state-of-the-art reconstructive dosimetry methods enabling estimation of local radiation doses and provides guidelines for medical handling of the exposed individuals. The review also presents the Chilean and Brazilian radiological accident cases to highlight the importance of reconstructive dosimetry. PMID:26445332

  14. Methods and procedures for external radiation dosimetry at ORNL

    SciTech Connect

    Gupton, E.D.

    1981-09-01

    Procedures, methods, materials, records, and reports used for accomplishing the personnel, external radiation monitoring program at Oak Ridge National Laboratory are described for the purpose of documenting what is done now for future reference. This document provides a description of the methods and procedures for external radiation metering, monitoring, dosimetry, and records which are in effect at ORNL July 1, 1981. This document does not include procedures for nuclear accident dosimetry except insofar as routine techniques may apply also to nuclear accident dosimetry capability.

  15. Development of a retrospective/fortuitous accident dosimetry service based on OSL of mobile phones.

    PubMed

    Smith, R W; Eakins, J S; Hager, L G; Rothkamm, K; Tanner, R J

    2015-04-01

    Work is presented on the development of a retrospective/fortuitous accident dosimetry service using optically stimulated luminescence of resistors found in mobile phones to determine the doses of radiation to members of the public following a radiological accident or terrorist incident. The system is described and discussed in terms of its likely accuracy in a real incident. PMID:25841040

  16. Bayesian Methods for Radiation Detection and Dosimetry

    SciTech Connect

    Peter G. Groer

    2002-09-29

    We performed work in three areas: radiation detection, external and internal radiation dosimetry. In radiation detection we developed Bayesian techniques to estimate the net activity of high and low activity radioactive samples. These techniques have the advantage that the remaining uncertainty about the net activity is described by probability densities. Graphs of the densities show the uncertainty in pictorial form. Figure 1 below demonstrates this point. We applied stochastic processes for a method to obtain Bayesian estimates of 222Rn-daughter products from observed counting rates. In external radiation dosimetry we studied and developed Bayesian methods to estimate radiation doses to an individual with radiation induced chromosome aberrations. We analyzed chromosome aberrations after exposure to gammas and neutrons and developed a method for dose-estimation after criticality accidents. The research in internal radiation dosimetry focused on parameter estimation for compartmental models from observed compartmental activities. From the estimated probability densities of the model parameters we were able to derive the densities for compartmental activities for a two compartment catenary model at different times. We also calculated the average activities and their standard deviation for a simple two compartment model.

  17. Proceedings of the third conference on radiation protection and dosimetry

    SciTech Connect

    Swaja, R.E.; Sims, C.S.; Casson, W.H.

    1991-10-01

    The Third Conference on Radiation Protection and Dosimetry was held during October 21--24, 1991, at the Sheraton Plaza Hotel in Orlando, Florida. This meeting was designed with the objectives of promoting communication among applied, research, regulatory, and standards personnel involved in radiation protection, and providing them with sufficient information to evaluate their programs. To meet these objectives, a technical program consisting of more than 75 invited and contributed oral presentations encompassing all aspects of radiation protection was prepared. General topics considered in the technical session included external dosimetry, internal dosimetry, instruments, accident dosimetry, regulations and standards, research advances, and applied program experience. In addition, special sessions were held to afford attendees the opportunity to make short presentations of recent work or to discuss topics of general interest. Individual reports are processed separately on the database.

  18. The Fukushima radiation accident: consequences for radiation accident medical management.

    PubMed

    Meineke, Viktor; Dörr, Harald

    2012-08-01

    The March 2011 radiation accident in Fukushima, Japan, is a textbook example of a radiation accident of global significance. In view of the global dimensions of the accident, it is important to consider the lessons learned. In this context, emphasis must be placed on consequences for planning appropriate medical management for radiation accidents including, for example, estimates of necessary human and material resources. The specific characteristics of the radiation accident in Fukushima are thematically divided into five groups: the exceptional environmental influences on the Fukushima radiation accident, particular circumstances of the accident, differences in risk perception, changed psychosocial factors in the age of the Internet and globalization, and the ignorance of the effects of ionizing radiation both among the general public and health care professionals. Conclusions like the need for reviewing international communication, interfacing, and interface definitions will be drawn from the Fukushima radiation accident. PMID:22951483

  19. The Fukushima radiation accident: consequences for radiation accident medical management.

    PubMed

    Meineke, Viktor; Dörr, Harald

    2012-08-01

    The March 2011 radiation accident in Fukushima, Japan, is a textbook example of a radiation accident of global significance. In view of the global dimensions of the accident, it is important to consider the lessons learned. In this context, emphasis must be placed on consequences for planning appropriate medical management for radiation accidents including, for example, estimates of necessary human and material resources. The specific characteristics of the radiation accident in Fukushima are thematically divided into five groups: the exceptional environmental influences on the Fukushima radiation accident, particular circumstances of the accident, differences in risk perception, changed psychosocial factors in the age of the Internet and globalization, and the ignorance of the effects of ionizing radiation both among the general public and health care professionals. Conclusions like the need for reviewing international communication, interfacing, and interface definitions will be drawn from the Fukushima radiation accident.

  20. Twenty-second ORNL intercomparison of criticality accident dosimetry systems, August 12-16, 1985

    SciTech Connect

    Swaja, R.E.; Oyan, R.; Sims, C.S.

    1986-05-01

    The twenty-second in a series of criticality accident dosimetry intercomparison studies was conducted at the Oak Ridge National Laboratory's Dosimetry Applications Research Facility during August 12-16, 1985. The Health Physics Research Reactor operated in the pulse mode over Storage Pit No. 1 was used to simulate three criticality accidents with different radiation fields. Participants from nine organizations measured neutron doses between 0.36 and 3.78 Gy and gamma doses between 0.22 and 0.80 Gy at area monitoring stations and on phantoms. Approximately 68% of all neutron dose estimates based on foil activation, thermoluminescent, hair activation, and blood sodium activation methods were within +-25% of reference values. About 44% of all gamma results measured using thermoluminescent dosimeters (TLD-700 or CaSO/sub 4/ phosphors) were within 20% of reference doses. The generally poor measurement accuracy exhibited in this study indicates a need for continuing ORNL accident dosimetry intercomparison and training programs.

  1. Initial radiation dosimetry at Hiroshima and Nagasaki

    SciTech Connect

    Loewe, W.E.

    1983-09-01

    The dosimetry of A-bomb survivors at Hiroshima and Nagasaki is discussed in light of the new dosimetry developed in 1980 by the author. The important changes resulting from the new dosimetry are the ratios of neutron to gamma doses, particularly at Hiroshima. The implications of these changes in terms of epidemiology and radiation protection standards are discussed. (ACR)

  2. Remote radiation dosimetry

    DOEpatents

    Braunlich, Peter F.; Tetzlaff, Wolfgang; Hegland, Joel E.; Jones, Scott C.

    1991-01-01

    Disclosed are methods and apparatus for remotely measuring radiation levels. Such are particularly useful for measuring relatively high levels or dosages of radiation being administered in radiation therapy. They are also useful for more general radiation level measurements where remote sensing from the remaining portions of the apparatus is desirable. The apparatus uses a beam generator, such as a laser beam, to provide a stimulating beam. The stimulating beam is preferably of wavelengths shorter than 6 microns, or more advantageously less than 2 microns. The stimulating beam is used to stimulate a remote luminescent sensor mounted in a probe which emits stored luminescent energy resulting from exposure of the sensor to ionizing radiation. The stimulating beam is communicated to the remote luminescent sensor via transmissive fiber which also preferably serves to return the emission from the luminescent sensor. The stimulating beam is advantageously split by a beam splitter to create a detector beam which is measured for power during a reading period during which the luminescent phosphor is read. The detected power is preferably used to control the beam generator to thus produce desired beam power during the reading period. The luminescent emission from the remote sensor is communicated to a suitable emission detector, preferably after filtering or other selective treatment to better isolate the luminescent emission.

  3. Remote radiation dosimetry

    DOEpatents

    Braunlich, P.F.; Tetzlaff, W.; Hegland, J.E.; Jones, S.C.

    1991-03-12

    Disclosed are methods and apparatus for remotely measuring radiation levels. Such are particularly useful for measuring relatively high levels or dosages of radiation being administered in radiation therapy. They are also useful for more general radiation level measurements where remote sensing from the remaining portions of the apparatus is desirable. The apparatus uses a beam generator, such as a laser beam, to provide a stimulating beam. The stimulating beam is preferably of wavelengths shorter than 6 microns, or more advantageously less than 2 microns. The stimulating beam is used to stimulate a remote luminescent sensor mounted in a probe which emits stored luminescent energy resulting from exposure of the sensor to ionizing radiation. The stimulating beam is communicated to the remote luminescent sensor via a transmissive fiber which also preferably serves to return the emission from the luminescent sensor. The stimulating beam is advantageously split by a beam splitter to create a detector beam which is measured for power during a reading period during which the luminescent phosphor is read. The detected power is preferably used to control the beam generator to thus produce desired beam power during the reading period. The luminescent emission from the remote sensor is communicated to a suitable emission detector, preferably after filtering or other selective treatment to better isolate the luminescent emission. 8 figures.

  4. Advances in radiation therapy dosimetry

    PubMed Central

    Paliwal, Bhudatt; Tewatia, Dinesh

    2009-01-01

    During the last decade, there has been an explosion of new radiation therapy planning and delivery tools. We went through a rapid transition from conventional three-dimensional (3D) conformal radiation therapy to intensity-modulated radiation therapy (IMRT) treatments, and additional new techniques for motion-adaptive radiation therapy are being introduced. These advances push the frontiers in our effort to provide better patient care; and with the addition of IMRT, temporal dimensions are major challenges for the radiotherapy patient dosimetry and delivery verification. Advanced techniques are less tolerant to poor implementation than are standard techniques. Mis-administrations are more difficult to detect and can possibly lead to poor outcomes for some patients. Instead of presenting a manual on quality assurance for radiation therapy, this manuscript provides an overview of dosimetry verification tools and a focused discussion on breath holding, respiratory gating and the applications of four-dimensional computed tomography in motion management. Some of the major challenges in the above areas are discussed. PMID:20098555

  5. 1983 international intercomparison of nuclear accident dosimetry systems at Oak Ridge National Laboratory

    SciTech Connect

    Swaja, R.E.; Greene, R.T.; Sims, C.S.

    1985-04-01

    An international intercomparison of nuclear accident dosimetry systems was conducted during September 12-16, 1983, at Oak Ridge National Laboratory (ORNL) using the Health Physics Research Reactor operated in the pulse mode to simulate criticality accidents. This study marked the twentieth in a series of annual accident dosimetry intercomparisons conducted at ORNL. Participants from ten organizations attended this intercomparison and measured neutron and gamma doses at area monitoring stations and on phantoms for three different shield conditions. Results of this study indicate that foil activation techniques are the most popular and accurate method of determining accident-level neutron doses at area monitoring stations. For personnel monitoring, foil activation, blood sodium activation, and thermoluminescent (TL) methods are all capable of providing accurate dose estimates in a variety of radiation fields. All participants in this study used TLD's to determine gamma doses with very good results on the average. Chemical dosemeters were also shown to be capable of yielding accurate estimates of total neutron plus gamma doses in a variety of radiation fields. While 83% of all neutron measurements satisfied regulatory standards relative to reference values, only 39% of all gamma results satisfied corresponding guidelines for gamma measurements. These results indicate that continued improvement in accident dosimetry evaluation and measurement techniques is needed.

  6. Radiation accident grips Goiania

    SciTech Connect

    Roberts, L.

    1987-11-20

    On 13 September two young scavengers in Goiania, Brazil, removed a stainless steel cylinder from a cancer therapy machine in an abandoned clinic, touching off a radiation accident second only to Chernobyl in its severity. On 18 September they sold the cylinder, the size of a 1-gallon paint can, to a scrap dealer for $25. At the junk yard an employee dismantled the cylinder and pried open the platinum capsule inside to reveal a glowing blue salt-like substance - 1400 curies of cesium-137. Fascinated by the luminescent powder, several people took it home with them. Some children reportedly rubbed in on their bodies like carnival glitter - an eerie image of how wrong things can go when vigilance over radioactive materials lapses. In all, 244 people in Goiania, a city of 1 million in central Brazil, were contaminated. The eventual toll, in terms of cancer or genetic defects, cannot yet be estimated. Parts of the city are cordoned off as radiation teams continue washing down buildings and scooping up radioactive soil. The government is also grappling with the political fallout from the accident.

  7. Criticality accident dosimetry by chromosomal analysis.

    PubMed

    Voisin, P; Roy, L; Hone, P A; Edwards, A A; Lloyd, D C; Stephan, G; Romm, H; Groer, P G; Brame, R

    2004-01-01

    The technique of measuring the frequency of dicentric chromosomal aberrations in blood lymphocytes was used to estimate doses in a simulated criticality accident. The simulation consisted of three exposures; approximately 5 Gy with a bare source and 1 and 2 Gy with a lead-shielded source. Three laboratories made separate estimates of the doses. These were made by the iterative method of apportioning the observed dicentric frequencies between the gamma and neutron components, taking account of a given gamma/neutron dose ratio, and referring the separated dicentric frequencies to dose-response calibration curves. An alternative method, based on Bayesian ideas, was employed. This was developed for interpreting dicentric frequencies in situations where the gamma/neutron ratio is uncertain. Both methods gave very similar results. One laboratory produced dose estimates close to the eventual exercise reference doses and the other laboratories estimated slightly higher values. The main reason for the higher values was the calibration relationships for fission neutrons.

  8. Performance of the CEDS Accident Dosimetry System at the 1995 Los Alamos National Laboratory Nuclear Accident Dosimetry Intercomparison

    SciTech Connect

    McMahan, K.L.; Schwanke, L.J.

    1996-12-01

    In July 1995, LANL hosted an accident dosimetry intercomparison. When all reactors on the Oak Ridge Reservation were idled in 1988, the Health Physics Research Reactor (HPRR), which had been used for 22 previous intercomparisons dating from 1965, was shut down for an indefinite period. The LANL group began characterization of two critical assemblies for dosimetry purposes. As a result, NAD-23 was conceived and 10 DOE facilities accepted invitations to participate in the intercomparison. This report is a summary of the performance of one of the participants, the Centralized External Dosimetry System (CEDS). The CEDS is a cooperative personnel dosimetry arrangement between three DOE sites in Oak Ridge, Tennessee. Many successes and failures are reported herein. Generally, the TL dosimeters performed poorly and always over-reported the delivered dose. The TLD processing procedures contain efforts that would lead to large biases in the reported absorbed dose, and omit several key steps in the TLD reading process. The supralinear behavior of lithium fluoride (LiF) has not been characterized for this particular dosimeter and application (i.e., in high-dose mixed neutron/gamma fields). The use of TLD materials may also be precluded given the limitations of the LiF material itself, the TLD reading system, and the upper dose level to which accident dosimetry systems are required to perform as set forth in DOE regulations. The indium foil results confirm the expected inability of that material to predict the magnitude of the wearer`s dose reliably, although it is quite suitable as a quick-sort material. Biological sample (hair) results were above the minimum detectable activity (MDA) for only one of the tests. Several questions as to the best methods for sample handling and processing remain.

  9. Biological effects of radiation accidents on humans. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1995-06-01

    The bibliography contains citations concerning the impact of radiation accidents on humans. Citations discuss exposure assessment, malfunction and misuse of radiation sources, dosimetry, radiation epidemiology, radiation-induced neoplasms, and nuclear facility licensing. Environmental and occupational exposures, case studies, nuclear fallout, and radiation effects on food chains are examined. (Contains 50-250 citations and includes a subject term index and title list.)

  10. Twenty-first nuclear accident dosimetry intercomparison study, August 6-10, 1984

    SciTech Connect

    Swaja, R.E.; Ragan, G.E.; Sims, C.S.

    1985-05-01

    The twenty-first in a series of nuclear accident dosimetry (NAD) intercomparison (NAD) studies was conducted at the Oak Ridge National Laboratory's Dosimetry Applications Research Facility during August 6-10, 1984. The Health Physics Research Reactor operated in the pulse mode was used to simulate three criticality accidents with different radiation fields. Participants from five organizations measured neutron doses between 0.53 and 4.36 Gy and gamma doses between 0.19 and 1.01 Gy at area monitoring stations and on phantoms. About 75% of all neutron dose estimates based on foil activation, hair activation, simulated blood sodium activation, and thermoluminescent methods were within +-25% of reference values. Approximately 86% of all gamma results measured using thermoluminescent (TLD-700 or CaSO/sub 4/) systems were within +-20% of reference doses which represents a significant improvement over previous studies. Improvements observed in the ability of intercomparison participants to estimate neutron and gamma doses under criticality accident conditions can be partly attributed to experience in previous NAD studies which have provided practical tests of dosimetry systems, enabled participants to improve evaluation methods, and standardized dose reporting conventions. 16 refs., 15 tabs.

  11. EPR dosimetry teeth in past and future accidents: A prospective look at a retrospective method

    SciTech Connect

    Haskell, E.; Kenner, G.; Hayes, R.; Chumak, V.; Shalom, S.

    1997-03-01

    Accurate assessments of doses received by individuals exposed to radiation from nuclear accidents and incidents such as those at Hiroshima and Nagasaki, the Nevada test site, Cheliabinsk and Mayak are required for epidemiological studies seeking to establish relationships between radiation dose and health effects. One method of retrospective dosimetry which allows for measurement of cumulative gamma ray doses received by exposed individuals is electron paramagnetic resonance spectroscopy (EPR) of tooth enamel. Tooth enamel stores and retains, indefinitely, information on absorbed radiation dose. And teeth are available in every population as a result of dental extraction for medical reasons including periodontal disease and impacted wisdom teeth. In the case of children, deciduous teeth, which are shed between the ages of 7 and 13, can be a very important dosimetric source if documented collection is implemented shortly following an accident.

  12. Nuclear accident dosimetry studies at Los Alamos National Laboratory

    SciTech Connect

    Casson, W.H.; Buhl, T.E.; Upp, D.L.

    1995-12-01

    Two critical assemblies have been characterized at the Los Alamos Critical Experiments Facility (LACEF) for use in testing nuclear accident dosimeters and related devices. These device, Godiva IV and SHEBA II, have very different characteristics in both operation and emitted neutron energy spectra. The Godiva assembly is a bare metal fast burst device with a hard spectrum. This spectrum can be modified by use of several shields including steel, concrete, and plexiglas. The modified spectra vary in both average neutron energy and in the specific distribution of the neutron energies in the intermediate energy range. This makes for a very favorable test arrangement as the response ratios between different activation foils used in accident dosimeters are significantly altered such as the ratio between gold, copper, and sulfur elements. The SHEBA device is a solution assembly which has both a slow ramp and decay period and a much softer spectrum. The uncertainly introduced in the response of fast decay foils such as indium can therefore be evaluated into the test results. The neutron energy spectrum for each configuration was measured during low power operations with a multisphere system. These measurements were extended to high dose pulsed operation by use of TLDs moderated TLDs, and special activation techniques. The assemblies were used in the testing of several accident dosimetry devices in studies modeled after the Nuclear Accident Dosimetry Studies that were conducted at Oak Ridge National Laboratory for about 25 years using the Health Physics Research Reactor. It is our intention to conduct these studies approximately annually for the evaluation of the nuclear accident dosimeter systems currently in use within the DOE, alternative systems used internationally, and new dosimeter designs being developed or considered for field application. Participation in selected studies will be open to all participants.

  13. Dosimetry of ionising radiation in modern radiation oncology

    NASA Astrophysics Data System (ADS)

    Kron, Tomas; Lehmann, Joerg; Greer, Peter B.

    2016-07-01

    Dosimetry of ionising radiation is a well-established and mature branch of physical sciences with many applications in medicine and biology. In particular radiotherapy relies on dosimetry for optimisation of cancer treatment and avoidance of severe toxicity for patients. Several novel developments in radiotherapy have introduced new challenges for dosimetry with small and dynamically changing radiation fields being central to many of these applications such as stereotactic ablative body radiotherapy and intensity modulated radiation therapy. There is also an increasing awareness of low doses given to structures not in the target region and the associated risk of secondary cancer induction. Here accurate dosimetry is important not only for treatment optimisation but also for the generation of data that can inform radiation protection approaches in the future. The article introduces some of the challenges and highlights the interdependence of dosimetric calculations and measurements. Dosimetric concepts are explored in the context of six application fields: reference dosimetry, small fields, low dose out of field, in vivo dosimetry, brachytherapy and auditing of radiotherapy practice. Recent developments of dosimeters that can be used for these purposes are discussed using spatial resolution and number of dimensions for measurement as sorting criteria. While dosimetry is ever evolving to address the needs of advancing applications of radiation in medicine two fundamental issues remain: the accuracy of the measurement from a scientific perspective and the importance to link the measurement to a clinically relevant question. This review aims to provide an update on both of these.

  14. Dosimetry of ionising radiation in modern radiation oncology.

    PubMed

    Kron, Tomas; Lehmann, Joerg; Greer, Peter B

    2016-07-21

    Dosimetry of ionising radiation is a well-established and mature branch of physical sciences with many applications in medicine and biology. In particular radiotherapy relies on dosimetry for optimisation of cancer treatment and avoidance of severe toxicity for patients. Several novel developments in radiotherapy have introduced new challenges for dosimetry with small and dynamically changing radiation fields being central to many of these applications such as stereotactic ablative body radiotherapy and intensity modulated radiation therapy. There is also an increasing awareness of low doses given to structures not in the target region and the associated risk of secondary cancer induction. Here accurate dosimetry is important not only for treatment optimisation but also for the generation of data that can inform radiation protection approaches in the future. The article introduces some of the challenges and highlights the interdependence of dosimetric calculations and measurements. Dosimetric concepts are explored in the context of six application fields: reference dosimetry, small fields, low dose out of field, in vivo dosimetry, brachytherapy and auditing of radiotherapy practice. Recent developments of dosimeters that can be used for these purposes are discussed using spatial resolution and number of dimensions for measurement as sorting criteria. While dosimetry is ever evolving to address the needs of advancing applications of radiation in medicine two fundamental issues remain: the accuracy of the measurement from a scientific perspective and the importance to link the measurement to a clinically relevant question. This review aims to provide an update on both of these. PMID:27351409

  15. Quantities and units in radiation protection dosimetry

    NASA Astrophysics Data System (ADS)

    Jennings, W. A.

    1994-08-01

    A new report, entitled Quantities and Units in Radiation Protection Dosimetry, has recently been published by the international Commission on Radiation Units and Measurements. That report (No. 51) aims to provide a coherent system of quantities and units for purposes of measurement and calculation in the assessment of compliance with dose limitations. The present paper provides an extended summary of that report, including references to the operational quantities needed for area and individual monitoring of external radiations.

  16. Criticality accident dosimetry systems: an international intercomparison at the SILENE reactor in 2002.

    PubMed

    Médioni, R; Asselineau, B; Verrey, B; Trompier, F; Itié, C; Texier, C; Muller, H; Pelcot, G; Clairand, I; Jacquet, X; Pochat, J L

    2004-01-01

    In criticality accident dosimetry and more generally for high dose measurements, special techniques are used to measure separately the gamma ray and neutron components of the dose. To improve these techniques and to check their dosimetry systems (physical and/or biological), a total of 60 laboratories from 29 countries (America, Europe, Asia) participated in an international intercomparaison, which took place in France from 9 to 21 June 2002, at the SILENE reactor in Valduc and at a pure gamma source in Fontenay-aux-Roses. This intercomparison was jointly organised by the IRSN and the CEA with the help of the NEA/OCDE and was partly supported by the European Communities. This paper describes the aim of this intercomparison, the techniques used by the participants and the two radiation sources and their characteristics. The experimental arrangements of the dosemeters for the irradiations in free air or on phantoms are given. Then the dosimetric quantities measured and reported by the participants are summarised, analysed and compared with the reference values. The present paper concerns only the physical dosimetry and essentially experiments performed on the SILENE facility. The results obtained with the biological dosimetry are published in two other papers of this issue.

  17. New dosimetry of atomic bomb radiations.

    PubMed

    Fry, R J; Sinclair, W K

    1987-10-10

    The reassessment of the radiation dosimetry from the Hiroshima and Nagasaki atomic bombs is almost complete. Since atomic bomb survivors provide a major source of data for estimates of risk of cancer induction by radiation the impact of the new dosimetry on risk estimates and radiation protection standards is important. The changes include an increase of about 20% in the estimated yield of the Hiroshima bomb and a reduction in the estimated doses from neutrons in both cities. The estimated neutron dose for Hiroshima is about 10% of the previous estimate. The neutron doses are now so small that direct estimates of neutron relative biological effectiveness may be precluded or be much more difficult. There is little change in most of the gamma ray organ doses because various changes in the new estimates tend to cancel each other out. The new estimate of the attenuation of the free-in-air kerma by the walls of the homes is about twice that used in the previous dosimetry. But the transmission of gamma radiation to the deep organs such as bone marrow is significantly greater than earlier estimates. Probably future risk estimates for radiogenic cancer will be somewhat higher because of both the new dosimetry and the new cancer mortality data. New risk estimates should be available in 1988.

  18. Advanced Semiconductor Dosimetry in Radiation Therapy

    SciTech Connect

    Rosenfeld, Anatoly B.

    2011-05-05

    Modern radiation therapy is very conformal, resulting in a complexity of delivery that leads to many small radiation fields with steep dose gradients, increasing error probability. Quality assurance in delivery of such radiation fields is paramount and requires real time and high spatial resolution dosimetry. Semiconductor radiation detectors due to their small size, ability to operate in passive and active modes and easy real time multichannel readout satisfy many aspects of in vivo and in a phantom quality assurance in modern radiation therapy. Update on the recent developments and improvements in semiconductor radiation detectors and their application for quality assurance in radiation therapy, based mostly on the developments at the Centre for Medical Radiation Physics (CMRP), University of Wollongong, is presented.

  19. Medical management principles for radiation accidents.

    PubMed

    Meineke, Viktor; van Beuningen, Dirk; Sohns, Torsten; Fliedner, Theodor M

    2003-03-01

    The medical management of radiation accidents requires intensive planning and action. This article looks at the medical management of recent radiation accidents to derive principles for structuring and organizing the treatment of patients who may have radiation-induced health impairments. Although the radiation accidents in Tokai-mura, Japan and Lilo, Georgia were small-scale accidents, they illustrate important and characteristic symptoms and clinical developments. There are lessons to be learned and conclusions to be drawn for the military medical officers concerned with problems of medical management after radiation accidents.

  20. Dosimetry for occupational exposure to cosmic radiation.

    PubMed

    Bartlett, D T; McAulay, I R; Schrewe, U J; Schnuer, K; Menzel, H G; Bottollier-Depois, J F; Dietze, G; Gmur, K; Grillmaeir, R E; Heinrich, W; Lim, T; Lindborg, L; Reitz, G; Schraube, H; Spurny, F; Tommasino, L

    1997-01-01

    In the course of their work, aircraft crew and frequent flyers are exposed to elevated levels of cosmic radiation of galactic and solar origin and secondary radiation produced in the atmosphere, aircraft structure, etc. This has been recognised for some time and estimates of the exposure of aircraft crew have been made previously and included in, for example, UNSCEAR (United Nations Scientific Committee on the Effects of Atomic Radiation) publications. The recent increased interest has been brought about by several factors--the consideration that the relative biological effectiveness of the neutron component as being underestimated; the trend towards higher cruising altitudes for subsonic commercial aircraft and business jet aircraft; and, most importantly, the recommendations of the International Commission on Radiological Protection (ICRP) in Publication 60, and the revision of the Euratom Basic Safety Standards Directive (BSS). In 1992, the European Dosimetry Group (EURADOS) established a Working Group to consider the exposure to cosmic radiation of aircraft crew, and the scientific and technical problems associated with radiation protection dosimetry for this occupational group. The Working Group was composed of fifteen scientists (plus a corresponding member) involved in this field of study and with knowledge of radiation measurement at aviation altitudes. This paper is based on the findings of this Working Group. Where arrangements are made to take account of the exposure of aircraft crew to cosmic radiation, dose estimation procedures will not be necessary for persons for whom total annual doses are not liable to exceed 1 mSv, and therefore, in general, for crew on aircraft not routinely flying above 8 km. Where estimates of effective dose and, in the case of female staff who are pregnant, equivalent dose to the embryo or fetus, are required (for regulatory or other purposes), it was concluded that the preferred procedure was to determine route doses and

  1. Technical basis for nuclear accident dosimetry at the Oak Ridge National Laboratory

    SciTech Connect

    Kerr, G.D.; Mei, G.T.

    1993-08-01

    The Oak Ridge National Laboratory (ORNL) Environmental, Safety, and Health Emergency Response Organization has the responsibility of providing analyses of personnel exposures to neutrons and gamma rays from a nuclear accident. This report presents the technical and philosophical basis for the dose assessment aspects of the nuclear accident dosimetry (NAD) system at ORNL. The issues addressed are regulatory guidelines, ORNL NAD system components and performance, and the interpretation of dosimetric information that would be gathered following a nuclear accident.

  2. The radiation dosimetry of intrathecally administered radionuclides

    SciTech Connect

    Stabin, M.G.; Evans, J.F.

    1999-01-01

    The radiation dose to the spine, spinal cord, marrow, and other organs of the body from intrathecal administration of several radiopharmaceuticals was studied. Anatomic models were developed for the spine, spinal cerebrospinal fluid (CSF), spinal cord, spinal skeleton, cranial skeleton, and cranial CSF. A kinetic model for the transport of CSF was used to determine residence times in the CSF; material leaving the CSF was thereafter assumed to enter the bloodstream and follow the kinetics of the radiopharmaceutical as if intravenously administered. The radiation transport codes MCNP and ALGAMP were used to model the electron and photon transport and energy deposition. The dosimetry of Tc-99m DTPA and HSA, In-111 DTPA, I-131 HSA, and Yb-169 DTPA was studied. Radiation dose profiles for the spinal cord and marrow in the spine were developed and average doses to all other organs were estimated, including dose distributions within the bone and marrow.

  3. The ENEA criticality accident dosimetry system: a contribution to the 2002 international intercomparison at the SILENE reactor.

    PubMed

    Gualdrini, G; Bedogni, R; Fantuzzi, E; Mariotti, F

    2004-01-01

    The present paper summarises the activity carried out at the ENEA Radiation Protection Institute for updating the methodologies employed for the evaluation of the neutron and photon dose to the exposed workers in case of a criticality accident, in the framework of the 'International Intercomparison of Criticality Accident Dosimetry Systems' (Silène reactor, IRSN-CEA-Valduc June 2002). The evaluation of the neutron spectra and the neutron dosimetric quantities relies on activation detectors and on unfolding algorithms. Thermoluminescent detectors are employed for the gamma dose measurement. The work is aimed at accurately characterising the measurement system and, at the same time, testing the algorithms. Useful spectral information were included, based on Monte Carlo simulations, to take into account the potential accident scenarios of practical interest. All along this exercise intercomparison a particular attention was devoted to the 'traceability' of all the experimental and computational parameters and therefore, aimed at an easy treatment by the user.

  4. EURADOS strategic research agenda: vision for dosimetry of ionising radiation.

    PubMed

    Rühm, W; Fantuzzi, E; Harrison, R; Schuhmacher, H; Vanhavere, F; Alves, J; Bottollier Depois, J F; Fattibene, P; Knežević, Ž; Lopez, M A; Mayer, S; Miljanić, S; Neumaier, S; Olko, P; Stadtmann, H; Tanner, R; Woda, C

    2016-02-01

    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). PMID:25752758

  5. Radiation dosimetry and biophysical models of space radiation effects

    NASA Technical Reports Server (NTRS)

    Cucinotta, Francis A.; Wu, Honglu; Shavers, Mark R.; George, Kerry

    2003-01-01

    Estimating the biological risks from space radiation remains a difficult problem because of the many radiation types including protons, heavy ions, and secondary neutrons, and the absence of epidemiology data for these radiation types. Developing useful biophysical parameters or models that relate energy deposition by space particles to the probabilities of biological outcomes is a complex problem. Physical measurements of space radiation include the absorbed dose, dose equivalent, and linear energy transfer (LET) spectra. In contrast to conventional dosimetric methods, models of radiation track structure provide descriptions of energy deposition events in biomolecules, cells, or tissues, which can be used to develop biophysical models of radiation risks. In this paper, we address the biophysical description of heavy particle tracks in the context of the interpretation of both space radiation dosimetry and radiobiology data, which may provide insights into new approaches to these problems.

  6. Radiation dosimetry and biophysical models of space radiation effects.

    PubMed

    Cucinotta, Francis A; Wu, Honglu; Shavers, Mark R; George, Kerry

    2003-06-01

    Estimating the biological risks from space radiation remains a difficult problem because of the many radiation types including protons, heavy ions, and secondary neutrons, and the absence of epidemiology data for these radiation types. Developing useful biophysical parameters or models that relate energy deposition by space particles to the probabilities of biological outcomes is a complex problem. Physical measurements of space radiation include the absorbed dose, dose equivalent, and linear energy transfer (LET) spectra. In contrast to conventional dosimetric methods, models of radiation track structure provide descriptions of energy deposition events in biomolecules, cells, or tissues, which can be used to develop biophysical models of radiation risks. In this paper, we address the biophysical description of heavy particle tracks in the context of the interpretation of both space radiation dosimetry and radiobiology data, which may provide insights into new approaches to these problems. PMID:12959127

  7. Proton minibeam radiation therapy: Experimental dosimetry evaluation

    SciTech Connect

    Peucelle, C.; Martínez-Rovira, I.; Prezado, Y.; Nauraye, C.; Patriarca, A.; Hierso, E.; Fournier-Bidoz, N.

    2015-12-15

    Purpose: Proton minibeam radiation therapy (pMBRT) is a new radiotherapy (RT) approach that allies the inherent physical advantages of protons with the normal tissue preservation observed when irradiated with submillimetric spatially fractionated beams. This dosimetry work aims at demonstrating the feasibility of the technical implementation of pMBRT. This has been performed at the Institut Curie - Proton Therapy Center in Orsay. Methods: Proton minibeams (400 and 700 μm-width) were generated by means of a brass multislit collimator. Center-to-center distances between consecutive beams of 3200 and 3500 μm, respectively, were employed. The (passive scattered) beam energy was 100 MeV corresponding to a range of 7.7 cm water equivalent. Absolute dosimetry was performed with a thimble ionization chamber (IBA CC13) in a water tank. Relative dosimetry was carried out irradiating radiochromic films interspersed in a IBA RW3 slab phantom. Depth dose curves and lateral profiles at different depths were evaluated. Peak-to-valley dose ratios (PVDR), beam widths, and output factors were also assessed as a function of depth. Results: A pattern of peaks and valleys was maintained in the transverse direction with PVDR values decreasing as a function of depth until 6.7 cm. From that depth, the transverse dose profiles became homogeneous due to multiple Coulomb scattering. Peak-to-valley dose ratio values extended from 8.2 ± 0.5 at the phantom surface to 1.08 ± 0.06 at the Bragg peak. This was the first time that dosimetry in such small proton field sizes was performed. Despite the challenge, a complete set of dosimetric data needed to guide the first biological experiments was achieved. Conclusions: pMBRT is a novel strategy in order to reduce the side effects of RT. This works provides the experimental proof of concept of this new RT method: clinical proton beams might allow depositing a (high) uniform dose in a brain tumor located in the center of the brain (7.5 cm depth

  8. An attempt to use sweeteners as a material for accident dosimetry.

    PubMed

    Kinoshita, Angela; José, Flávio A; Baffa, Oswaldo

    2010-02-01

    In case of a radiological accident, it is important to determine the exposure to radiation of the general population. Several materials can be used to reconstruct the exposed dose. Tooth enamel has been studied for a long time, and now the procedures to determine the dose are well established for in vitro measurements. Many materials have been investigated by different techniques: sugar, wall bricks, roof tiles, plastics, watch glass, ruby present in watches, medicines carried by persons and shell button, among others. In this work an attempt is made to use sweeteners as a possible accident dosimeter material because they are becoming increasingly common. Sweeteners based on saccharine, cyclamate, stevia, and aspartame were acquired in local stores, and ESR spectrum was recorded before and after gamma irradiation. Spectrum simulation demonstrated that there are two main radicals with g = 2.0063, A = 1.6 mT, and g = 2.0048, A = 5 mT due to lactose. For the better characterization of spectroscopic and dosimetric properties of these materials, higher microwave frequency (K-band, nu approximately 24 GHz) was also employed. Experiments in X-band (nu approximately 9 GHz) showed that low dose levels of 500 mGy can be measured with this material, demonstrating the potential use of sweeteners for retrospective dosimetry.

  9. Neutron dosimetry and radiation damage calculations for HFBR

    SciTech Connect

    Greenwood, L.R.; Ratner, R.T.

    1998-03-01

    Neutron dosimetry measurements have been conducted for various positions of the High Flux Beam Reactor (HFBR) at Brookhaven National Laboratory (BNL) in order to measure the neutron flux and energy spectra. Neutron dosimetry results and radiation damage calculations are presented for positions V10, V14, and V15.

  10. [Instrumental radiofrequency electromagnetic radiation dosimetry: general principals and modern methodology].

    PubMed

    Perov, S Iu; Kudriashov, Iu B; Rubtsova, N B

    2012-01-01

    The modern experimental radiofrequency electromagnetic field dosimetry approach has been considered. The main principles of specific absorbed rate measurement are analyzed for electromagnetic field biological effect assessment. The general methodology of specific absorbed rate automated dosimetry system applied to establish the compliance of radiation sources with the safety standard requirements (maximum permissible levels and base restrictions) is described.

  11. Subwavelength films for standoff radiation dosimetry

    SciTech Connect

    Alvine, Kyle J.; Bernacki, Bruce E.; Bennett, Wendy D.; Schemer-Kohrn, Alan L.; Suter, Jonathan D.

    2015-05-22

    We present optical subwavelength nanostructure architecture suitable for standoff radiation dosimetry with remote optical readout in the visible or infrared spectral regions. To achieve this, films of subwavelength structures are fabricated over several square inches via the creation of a 2D non-close packed (NCP) array template of radiation-sensitive polymeric nanoparticles, followed by magnetron sputtering of a metallic coating to form a 2D array of separated hemispherical nanoscale metallic shells. The nanoshells are highly reflective at resonance in the visible or infrared depending on design. These structures and their behavior are based on the open ring resonator (ORR) architecture and have their analog in resonant inductive-capacitive (LC) circuits, which display a resonance wavelength that is inversely proportional to the square root of the product of the inductance and capacitance. Therefore, any modification of the nanostructure material properties due to radiation alters the inductive or capacitive behavior of the subwavelength features, which in turn changes their optical properties resulting in a shift in the optical resonance. This shift in resonance may be remotely interrogated actively using either laser illumination or passively by hyperspectral or multispectral sensing with broadband illumination. These structures may be designed to be either anisotropic or isotropic, which can also offer polarization-sensitive interrogation. We present experimental measurements of a radiation induced shift in the optical resonance of a subwavelength film after exposure to an absorbed dose of gamma radiation from 2 Mrad up to 62 Mrad demonstrating the effect. Interestingly the resonance shift is non-monotonic for this material system and possible radiation damage mechanisms to the nanoparticles are discussed.

  12. Film Dosimetry for Intensity Modulated Radiation Therapy

    NASA Astrophysics Data System (ADS)

    Benites-Rengifo, J.; Martínez-Dávalos, A.; Celis, M.; Lárraga, J.

    2004-09-01

    Intensity Modulated Radiation Therapy (IMRT) is an oncology treatment technique that employs non-uniform beam intensities to deliver highly conformal radiation to the targets while minimizing doses to normal tissues and critical organs. A key element for a successful clinical implementation of IMRT is establishing a dosimetric verification process that can ensure that delivered doses are consistent with calculated ones for each patient. To this end we are developing a fast quality control procedure, based on film dosimetry techniques, to be applied to the 6 MV Novalis linear accelerator for IMRT of the Instituto Nacional de Neurología y Neurocirugía (INNN) in Mexico City. The procedure includes measurements of individual fluence maps for a limited number of fields and dose distributions in 3D using extended dose-range radiographic film. However, the film response to radiation might depend on depth, energy and field size, and therefore compromise the accuracy of measurements. In this work we present a study of the dependence of Kodak EDR2 film's response on the depth, field size and energy, compared with those of Kodak XV2 film. The first aim is to devise a fast and accurate method to determine the calibration curve of film (optical density vs. doses) commonly called a sensitometric curve. This was accomplished by using three types of irradiation techniques: Step-and-shoot, dynamic and static fields.

  13. Subwavelength films for standoff radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Alvine, Kyle J.; Bernacki, Bruce E.; Bennett, Wendy D.; Schemer-Kohrn, Alan; Suter, Jonathan D.

    2015-05-01

    We present optical subwavelength nanostructure architecture suitable for standoff radiation dosimetry with remote optical readout in the visible or infrared spectral regions. To achieve this, films of subwavelength structures are fabricated over several square inches via the creation of a 2D non-close packed (NCP) array template of radiationsensitive polymeric nanoparticles, followed by magnetron sputtering of a metallic coating to form a 2D array of separated hemispherical nanoscale metallic shells. The nanoshells are highly reflective at resonance in the visible or infrared depending on design. These structures and their behavior are based on the open ring resonator (ORR) architecture and have their analog in resonant inductive-capacitive (LC) circuits, which display a resonance wavelength that is inversely proportional to the square root of the product of the inductance and capacitance. Therefore, any modification of the nanostructure material properties due to radiation alters the inductive or capacitive behavior of the subwavelength features, which in turn changes their optical properties resulting in a shift in the optical resonance. This shift in resonance may be remotely interrogated actively using either laser illumination or passively by hyperspectral or multispectral sensing with broadband illumination. These structures may be designed to be either anisotropic or isotropic, which can also offer polarization-sensitive interrogation. We present experimental measurements of a radiation induced shift in the optical resonance of a subwavelength film after exposure to an absorbed dose of gamma radiation from 2 Mrad up to 62 Mrad demonstrating the effect. Interestingly the resonance shift is non-monotonic for this material system and possible radiation damage mechanisms to the nanoparticles are discussed.

  14. Review of the near-earth space radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Guo, Jianming; Chen, Xiaoqian; Li, Shiyou

    2016-07-01

    The near-earth space radiation environment has a great effect to the spacecraft and maybe do harm to the astronaut's health. Thus, how to measure the radiation has become a serious challenge. In order to provide sufficient protection both for astronauts and for instruments on-board, dose equivalent and linear energy transfer should be measured instead of merely measuring total radiation dose. This paper reviews the methods of radiation measurement and presents a brief introduction of dosimetry instruments. The method can be divided into two different kinds, i.e., positive dosimetry and passive dosimetry. The former usually includes electronic devices which can be used for data storage and can offer simultaneous monitoring on space radiation. The passive dosimetry has a much simple structure, and need extra operation after on-orbit missions for measuring. To get more reliable data of radiation dosimetry, various instruments and methods had been applied in the spacecrafts and the manned spacecrafts in particular. The outlook of the development in the space radiation dosimetry measurement is also presented.

  15. Radiation dosimetry onboard the International Space Station ISS.

    PubMed

    Berger, Thomas

    2008-01-01

    Besides the effects of the microgravity environment, and the psychological and psychosocial problems encountered in confined spaces, radiation is the main health detriment for long duration human space missions. The radiation environment encountered in space differs in nature from that on earth, consisting mostly of high energetic ions from protons up to iron, resulting in radiation levels far exceeding the ones encountered on earth for occupational radiation workers. Therefore the determination and the control of the radiation load on astronauts is a moral obligation of the space faring nations. The requirements for radiation detectors in space are very different to that on earth. Limitations in mass, power consumption and the complex nature of the space radiation environment define and limit the overall construction of radiation detectors. Radiation dosimetry onboard the International Space Station (ISS) is onboard the International Space Station (ISS) is accomplished to one part as "operational" dosimetry accomplished to one part as "operational" dosimetry aiming for area monitoring of the radiation environment as well as astronaut surveillance. Another part focuses on "scientific" dosimetry aiming for a better understanding of the radiation environment and its constitutes. Various research activities for a more detailed quantification of the radiation environment as well as its distribution in and outside the space station have been accomplished in the last years onboard the ISS. The paper will focus on the current radiation detectors onboard the ISS, their results, as well as on future planned activities.

  16. Atomic bomb and accident dosimetry with ESR: natural rocks and human tooth in-vivo spectrometer.

    PubMed

    Ikeya, M; Ishii, H

    1989-01-01

    ESR dosimetry of some construction materials at Hiroshima and Nagasaki was carried out to determine the A-bomb radiation dose. Some minerals exposed to low-level natural radiation over a given geological time period can be also used to determine the intense A-bomb radiation dose. Finally, an ESR cavity and a special NdBFe (Neomax) magnet system for in-vivo measurement of radiation dose of a human tooth without extraction is designed and manufactured.

  17. On the use of new generation mobile phone (smart phone) for retrospective accident dosimetry

    NASA Astrophysics Data System (ADS)

    Lee, J. I.; Chang, I.; Pradhan, A. S.; Kim, J. L.; Kim, B. H.; Chung, K. S.

    2015-11-01

    Optically stimulated luminescence (OSL) characteristics of resistors, inductors and integrated-circuit (IC) chips, extracted from new generation smart phones, were investigated for the purpose of retrospective accident dosimetry. Inductor samples were found to exhibit OSL sensitivity about 5 times and 40 times higher than that of the resistors and the IC chips, respectively. On post-irradiation storage, the resistors exhibited a much higher OSL fading (about 80 % in 36 h as compared to the value 3 min after irradiation) than IC chips (about 20 % after 36 h) and inductors (about 50 % in 36 h). Higher OSL sensitivity, linear dose response (from 8.7 mGy up to 8.9 Gy) and acceptable fading make inductors more attractive for accident dosimetry than widely studied resistors.

  18. Twenty new ISO standards on dosimetry for radiation processing

    NASA Astrophysics Data System (ADS)

    Farrar, H., IV

    2000-03-01

    Twenty standards on essentially all aspects of dosimetry for radiation processing were published as new ISO standards in December 1998. The standards are based on 20 standard practices and guides developed over the past 14 years by Subcommittee E10.01 of the American Society for Testing and Materials (ASTM). The transformation to ISO standards using the 'fast track' process under ISO Technical Committee 85 (ISO/TC85) commenced in 1995 and resulted in some overlap of technical information between three of the new standards and the existing ISO Standard 11137 Sterilization of health care products — Requirements for validation and routine control — Radiation sterilization. Although the technical information in these four standards was consistent, compromise wording in the scopes of the three new ISO standards to establish precedence for use were adopted. Two of the new ISO standards are specifically for food irradiation applications, but the majority apply to all forms of gamma, X-ray, and electron beam radiation processing, including dosimetry for sterilization of health care products and the radiation processing of fruit, vegetables, meats, spices, processed foods, plastics, inks, medical wastes, and paper. Most of the standards provide exact procedures for using individual dosimetry systems or for characterizing various types of irradiation facilities, but one covers the selection and calibration of dosimetry systems, and another covers the treatment of uncertainties using the new ISO Type A and Type B evaluations. Unfortunately, nine of the 20 standards just adopted by the ISO are not the most recent versions of these standards and are therefore already out of date. To help solve this problem, efforts are being made to develop procedures to coordinate the ASTM and ISO development and revision processes for these and future ASTM-originating dosimetry standards. In the meantime, an additional four dosimetry standards have recently been published by the ASTM but

  19. Cytogenetic damage in lymphocytes for the purpose of dose reconstruction: a review of three recent radiation accidents.

    PubMed

    Wojcik, A; Gregoire, E; Hayata, I; Roy, L; Sommer, S; Stephan, G; Voisin, P

    2004-01-01

    The analysis of chromosomal aberrations in peripheral blood of radiation accident victims is an established method of biological dosimetry. The dose estimate on the basis of an in vitro calibration curve is straightforward when the radiation exposure is homogeneous and the analysis not delayed. In recent years three radiation accidents occurred, where the irradiation or sampling conditions precluded a simple estimation of the dose. During the Georgian accident soldiers carried in their pockets small sources of 137Cs leading to partial and protracted body exposures. During the Tokai-mura accident, three employees involved in the process of 235U enrichment were exposed to very high doses of gamma rays and neutrons. During the Bialystok accident, five patients with breast cancer undergoing radiotherapy were exposed to a single dose of electrons which reached about 100 Gy. In the present paper the approaches chosen to estimate, by cytogenetic methods, the doses absorbed by the people involved in the accidents are described. PMID:15162038

  20. Cytogenetic damage in lymphocytes for the purpose of dose reconstruction: a review of three recent radiation accidents.

    PubMed

    Wojcik, A; Gregoire, E; Hayata, I; Roy, L; Sommer, S; Stephan, G; Voisin, P

    2004-01-01

    The analysis of chromosomal aberrations in peripheral blood of radiation accident victims is an established method of biological dosimetry. The dose estimate on the basis of an in vitro calibration curve is straightforward when the radiation exposure is homogeneous and the analysis not delayed. In recent years three radiation accidents occurred, where the irradiation or sampling conditions precluded a simple estimation of the dose. During the Georgian accident soldiers carried in their pockets small sources of 137Cs leading to partial and protracted body exposures. During the Tokai-mura accident, three employees involved in the process of 235U enrichment were exposed to very high doses of gamma rays and neutrons. During the Bialystok accident, five patients with breast cancer undergoing radiotherapy were exposed to a single dose of electrons which reached about 100 Gy. In the present paper the approaches chosen to estimate, by cytogenetic methods, the doses absorbed by the people involved in the accidents are described.

  1. Third conference on radiation protection and dosimetry. Program and abstracts

    SciTech Connect

    1991-01-01

    This conference has been designed with the objectives of promoting communication among applied, research, regulatory, and standards personnel involved in radiation protection and providing them with sufficient information to evaluate their programs. To partly fulfill these objectives, a technical program consisting of more than 75 invited and contributed oral presentations encompassing all aspects of radiation protection has been prepared. General topics include external dosimetry, internal dosimetry, instruments, regulations and standards, accreditation and test programs, research advances, and applied program experience. This publication provides a summary of the technical program and a collection of abstracts of the oral presentations.

  2. NCRP Program Area Committee 6: Radiation Measurements and Dosimetry.

    PubMed

    Simon, Steven L; Zeman, Gary H

    2016-02-01

    Program Area Committee (PAC) 6 of the National Council on Radiation Protection and Measurements provides guidance for radiation measurements and dosimetry--one of the most fundamental scientific areas of the Council's expertise. Seminal reports published by PAC 6 over many decades have documented the scientific and technical foundations of radiation measurements and dosimetry for generations of radiation scientists and radiation protection professionals. Ongoing work of PAC 6 is driven by advancing technology, such as development of new types of instruments, biodosimetry and nanotechnology; by evolving understanding of radiation hazards, such as effects on the lens of the eye and risks as from some high-dose medical imaging procedures; and by new situations faced in the modern socio-political environment including radiological and nuclear threats. The activities of PAC 6 are intended to formulate and document the dosimetric framework for radiological science to address these ever-emerging challenges. PMID:26717161

  3. NCRP Program Area Committee 6: Radiation Measurements and Dosimetry.

    PubMed

    Simon, Steven L; Zeman, Gary H

    2016-02-01

    Program Area Committee (PAC) 6 of the National Council on Radiation Protection and Measurements provides guidance for radiation measurements and dosimetry--one of the most fundamental scientific areas of the Council's expertise. Seminal reports published by PAC 6 over many decades have documented the scientific and technical foundations of radiation measurements and dosimetry for generations of radiation scientists and radiation protection professionals. Ongoing work of PAC 6 is driven by advancing technology, such as development of new types of instruments, biodosimetry and nanotechnology; by evolving understanding of radiation hazards, such as effects on the lens of the eye and risks as from some high-dose medical imaging procedures; and by new situations faced in the modern socio-political environment including radiological and nuclear threats. The activities of PAC 6 are intended to formulate and document the dosimetric framework for radiological science to address these ever-emerging challenges.

  4. Nineteenth nuclear accident dosimetry intercomparison study, August 9-13, 1982

    SciTech Connect

    Greene, R.T.; Sims, C.C.; Swaja, R.E.

    1983-11-01

    The Nineteenth Nuclear Accident Dosimetry Intercomparison Study was held August 9 to 13, 1982, at the Oak Ridge National Laboratory using the Health Physics Research Reactor operated in the pulse mode to simulate nuclear criticality accidents. Participants from eight organizations measured neutron and gamma doses at air stations and on phantoms for three different shielding conditions. Measured results were compared to nuclear industry guidelines for criticality accident dosimeters which suggest accuracies of +-25% for neutron dose and +-20% for gamma dose. Seventy-two percent of the neutron dose measurements using foil activation, sodium activation, hair sulfur activation, and thermoluminescent methods met the guidelines while less than 40% of the gamma dose measurements were within +-20% of reference values. The softest neutron energy spectrum (also lowest neutron/gamma dose ratio) provided the most difficulty in measuring neutron and gamma doses. Results of this study indicate the need for continued intercomparison and testing of nuclear accident dosimetry systems and for training of evaluating personnel. 14 references, 7 figures, 16 tables.

  5. Personnel radiation dosimetry symposium: program and abstracts

    SciTech Connect

    Not Available

    1984-10-01

    The purpose was to provide applied and research dosimetrists with sufficient information to evaluate the status and direction of their programs relative to the latest guidelines and techniques. A technical program was presented concerning experience, requirements, and advances in gamma, beta, and neutron personnel dosimetry.

  6. EPR dosimetry of teeth in past and future accidents: a prospective look at a retrospective method

    SciTech Connect

    Haskell, E.H.; Kenner, G.H.; Hayes, R.B.; Chumak, V.; Shalom, S.

    1996-01-01

    Electron paramagnetic resonance spectroscopy (EPR) of tooth enamel is a relatively new technique for retrospective dosimetry that in the past two years has seen increasing effort towards its development and evaluation. Efforts have centered on determining the accuracy which may be achieved with current measurement techniques as well as the minimum doses detectable. The study was focused on evaluating some factors which influence the accuracy of EPR dosimetry of enamel. Reported are studies on sample intercomparisions, instrumental considerations, and effects of dental x-rays, environmental sunlight and ultraviolet radiation.

  7. Applications of nuclear data in human radiation dosimetry

    SciTech Connect

    Kerr, G.D.; Eckerman, K.F. )

    1991-01-01

    Individuals are exposed to ionizing radiations in two ways: from radiation sources external to the body or from internal sources. In either case, the magnitude of the radiation dose to the sensitive tissues of the body is of primary concern. Radiation dose (or absorbed dose) is a physical quantity defined as the amount of ionizing energy absorbed per unit mass of material. For radiation protection purposes, however, it is also necessary to use the dose equivalent, which includes modifiers of absorbed dose to more fully reflect the biological considerations associated with different ionizing radiations. A research group at Oak Ridge National Laboratory has focused on defining the exposure-dose relationship (i.e., the relationship between radiation exposure from internal or external sources and the radiation dose received by tissues of the body). Although radiation can be readily detected and measured, it is not feasible to make direct measurements of the dose within the organs and tissues of the body. Nuclear data have been extensively used in these studies but improvements are needed in the current nuclear data base. Examples of these applications include studies dealing with (a) the application of the recommendations of Publication 26 of the International Committee on Radiological Protection in the dosimetry of internally deposited radionuclides and (b) the reassessment of radiation dosimetry for the atomic bombs in Hiroshima and Nagasaki.

  8. Appropriate radiation accident medical management: necessity of extensive preparatory planning.

    PubMed

    Dörr, H D; Meineke, V

    2006-11-01

    Despite the rareness of radiation accidents, their potential consequences can be very serious, and appropriate medical management requires sufficient preparatory planning. To identify necessary factors for sufficient preparatory planning, three different radiation accidents were analyzed, i.e. the accidents in Goiânia, Brazil, 1987; Lilo, Georgia, 1997; and Tokai-mura, Japan, 1999. These radiation accidents have been chosen specifically because they provide a wide spectrum of potential radiation accident scenarios. After a brief description of the accidents and the following medical management, the measures taken are analyzed in terms of diagnosing radiation-induced health damage, determining the cause, dealing with contamination/incorporation, pathophysiological and therapeutic principles, preparatory planning, national and international cooperation and training. Several important factors are identified that should be considered in preparatory planning, i.e. preventing delayed diagnosis and training of medical personnel. Due to limited national resources, an intensified international cooperation to manage medical radiation accidents is of great importance.

  9. Dissolution rate and radiation dosimetry of metal tritides

    SciTech Connect

    Cheng, Y.

    1993-12-31

    Metal tritides including titanium tritide (Ti{sup 3}H{sub x}) and erbium tritide (Er{sup 3}H{sub x}) have been used as components of neutron generators. These compounds can be released to the air as aerosols during fabrication, assembling, and testing of components or in accidental or fugitive releases; as a result, workers may be exposed to these compounds by inhalation. A joint research project between Sandia National Laboratories and the Inhalation Toxicology Research Institute was initiated to investigate the solubility of metal tritide particles, to determine retention and translocation of inhaled particles in animals, and to develop an internal dosimetry model. The current understanding of metal tritides and their radiation dosimetry for internal exposure is very limited. The ICRP Report 30 does not provide for tritium dosimetry in metal tritide form. The current radiation protection guidelines for metal tritide particles are based on the assumption that the biological behavior is similar to tritiated water which could be easily absorbed into body fluid, and therefore, a relatively short biological half life (10 days). If the solubility is low, the biological half life of metal tritide particles and the dosimetry of inhalation exposure to these particles could be quite different from tritiated water. This would have significant implications in the current health protection guidelines including annual limits of intakes and derived air concentrations. The preliminary results of our metal tritide dissolution study indicated that the solubility of titanium tritide is low.

  10. Probabilistic accident consequence uncertainty analysis -- Uncertainty assessment for internal dosimetry. Volume 2: Appendices

    SciTech Connect

    Goossens, L.H.J.; Kraan, B.C.P.; Cooke, R.M.; Harrison, J.D.; Harper, F.T.; Hora, S.C.

    1998-04-01

    The development of two new probabilistic accident consequence codes, MACCS and COSYMA, was completed in 1990. These codes estimate the consequence from the accidental releases of radiological material from hypothesized accidents at nuclear installations. In 1991, the US Nuclear Regulatory Commission and the Commission of the European Communities began cosponsoring a joint uncertainty analysis of the two codes. The ultimate objective of this joint effort was to systematically develop credible and traceable uncertainty distributions for the respective code input variables. A formal expert judgment elicitation and evaluation process was identified as the best technology available for developing a library of uncertainty distributions for these consequence parameters. This report focuses on the results of the study to develop distribution for variables related to the MACCS and COSYMA internal dosimetry models. This volume contains appendices that include (1) a summary of the MACCS and COSYMA consequence codes, (2) the elicitation questionnaires and case structures, (3) the rationales and results for the panel on internal dosimetry, (4) short biographies of the experts, and (5) the aggregated results of their responses.

  11. ELECTRON PARAMAGNETIC RESONANCE DOSIMETRY FOR A LARGE-SCALE RADIATION INCIDENT

    PubMed Central

    Swartz, Harold M.; Flood, Ann Barry; Williams, Benjamin B.; Dong, Ruhong; Swarts, Steven G.; He, Xiaoming; Grinberg, Oleg; Sidabras, Jason; Demidenko, Eugene; Gui, Jiang; Gladstone, David J.; Jarvis, Lesley A.; Kmiec, Maciej M.; Kobayashi, Kyo; Lesniewski, Piotr N.; Marsh, Stephen D.P.; Matthews, Thomas P.; Nicolalde, Roberto J.; Pennington, Patrick M.; Raynolds, Timothy; Salikhov, Ildar; Wilcox, Dean E.; Zaki, Bassem I.

    2013-01-01

    With possibilities for radiation terrorism and intensified concerns about nuclear accidents since the recent Fukushima Daiichi event, the potential exposure of large numbers of individuals to radiation that could lead to acute clinical effects has become a major concern. For the medical community to cope with such an event and avoid overwhelming the medical care system, it is essential to identify not only individuals who have received clinically significant exposures and need medical intervention but also those who do not need treatment. The ability of electron paramagnetic resonance to measure radiation-induced paramagnetic species, which persist in certain tissues (e.g., teeth, fingernails, toenails, bone, and hair), has led this technique to become a prominent method for screening significantly exposed individuals. Although the technical requirements needed to develop this method for effective application in a radiation event are daunting, remarkable progress has been made. In collaboration with General Electric, and through funding committed by the Biomedical Advanced Research and Development Authority, electron paramagnetic resonance tooth dosimetry of the upper incisors is being developed to become a Food and Drug Administration-approved and manufacturable device designed to carry out triage for a threshold dose of 2 Gy. Significant progress has also been made in the development of electron paramagnetic resonance nail dosimetry based on measurements of nails in situ under point-of-care conditions, and in the near future this may become a second field-ready technique. Based on recent progress in measurements of nail clippings, we anticipate that this technique may be implementable at remotely located laboratories to provide additional information when the measurements of dose on site need to be supplemented. We conclude that electron paramagnetic resonance dosimetry is likely to be a useful part of triage for a large-scale radiation incident. PMID:22850230

  12. Internal radiation dosimetry for clinical testing of radiolabeled monoclonal antibodies

    SciTech Connect

    Fisher, D.R.; Durham, J.S.; Hui, T.E.; Hill, R.L.

    1990-11-01

    In gauging the efficacy of radiolabeled monoclonal antibodies in cancer treatment, it is important to know the amount of radiation energy absorbed by tumors and normal tissue per unit administered activity. This paper describes methods for estimating absorbed doses to human tumors and normal tissues, including intraperitoneal tissue surfaces, red marrow, and the intestinal tract from incorporated radionuclides. These methods use the Medical Internal Radiation Dose (MIRD) scheme; however, they also incorporate enhancements designed to solve specific dosimetry problems encountered during clinical studies, such as patient-specific organ masses obtained from computerized tomography (CT) volumetrics, estimates of the dose to tumor masses within normal organs, and multicellular dosimetry for studying dose inhomogeneities in solid tumors. Realistic estimates of absorbed dose are provided within the short time requirements of physicians so that decisions can be made with regard to patient treatment and procurement of radiolabeled antibodies. Some areas in which further research could improve dose assessment are also discussed. 16 refs., 3 figs.

  13. Medical Radiation Dosimetry: Concepts and Needs

    SciTech Connect

    Kron, Tomas

    2011-05-05

    Radiation is used widely used in medicine for diagnostic and therapeutic applications. Both the desired effects and the potential detrimental side effects depend on the radiation dose delivered. As such it is essential to determining the radiation dose received by patients as accurately as needed to optimise the radiation procedure. Solid state dosimeters are increasingly used in medicine because of their small physical size, high sensitivity and usually low cost. Combining multiple detectors allows the detection of radiation dose distributions, an application where the distinction between radiation dosimeter and image detector starts to blur. Given the rapid development of detector technology it can be expected that the utilisation of solid-state dosimeters in medicine will continue to increase.

  14. METHOD AND MEANS FOR RADIATION DOSIMETRY

    DOEpatents

    Shulte, J.W.; Suttle, J.F.

    1958-02-18

    This patent relates to a method and device for determining quantities of gamma radiation and x radiation by exposing to such radiation a mature of a purified halogenated hydrocarbon chosen from the class consisting of chloroform, bromoform, tetrachloroethane and 1,1,2trichloroethane, and a minor quantity of a sensitizer chosen from the class consisting of oxygen, benzoyl peroxide, sodium peroxide, and nitrobenzene, the proportion of the sensitizer being at least about 10/sup -5/ moles per cubic centimeter of halogenated hydrocarbon, the total amount of sensitizer depending upon the range of radiation to be measured, and chemically measuring the amount of decomposition generated by the irradiation of the sensitized halogenated hydrocarbon.

  15. Proceedings of the second conference on radiation protection and dosimetry

    SciTech Connect

    Swaja, R. E.; Sims, C. S.

    1988-11-01

    The Second Conference on Radiation Protection and Dosimetry was held during October 31--November 3, 1988, at the Holiday Inn, Crowne Plaza Hotel in Orlando, Florida. This meeting was designed with the objectives of promoting communication among applied, research, regulatory, and standards personnel involved in radiation protection and providing them with sufficient information to evaluate their programs. To facilitate meeting these objectives, a technical program consisting of more than 75 invited and contributed oral presentations encompassing all aspects of radiation protection was prepared. General topics considered in the technical sessions included external dosimetry, internal dosimetry, calibration, standards and regulations, instrumentation, accreditation and test programs, research advances, and applied program experience. In addition, special sessions were held to afford attendees the opportunity to make short presentations of recent work or to discuss topics of general interest. This document provides a summary of the conference technical program and a partial collection of full papers for the oral presentations in order of delivery. Individual papers were processed separately for the data base.

  16. High LET, passive space radiation dosimetry and spectrometry

    SciTech Connect

    Benton, E.V.; Frank, A.L.; Benton, E.R.; Keegan, R.P.; Frigo, L.A.; Sanner, D.; Rowe, V.

    1995-03-01

    The development of high linear energy transfer (LET), passive radiation dosimetry and spectrometry is needed for the purpose of accurate determination of equivalent doses and assessment of health risks to astronauts on long duration missions. Progress in the following research areas is summerized: intercomparisons of cosmic ray equivalent dose and LET spectra measurements between STS missions and between astronauts; increases LET spectra measurement accuracy with ATAS; space radiation measurements for intercomparisons of passive (PNTD, TLD, TRND, Emulsion) and active (TEPC, RME-111) dosimeters; interaction of cosmic ray particles with nuclei in matter; radiation measurements after long duration space exposures; ground based dosimeter calibrations; neutron detector calibrations; radiation measurements on Soviet/Russian spacecraft; space radiation measurements under thin shielding; and space radiation. Separate abstracts were prepared for articles from this report.

  17. High LET, passive space radiation dosimetry and spectrometry

    NASA Technical Reports Server (NTRS)

    Benton, E. V.; Frank, A. L.; Benton, E. R.; Keegan, R. P.; Frigo, L. A.; Sanner, D.; Rowe, V.

    1995-01-01

    The development of high linear energy transfer (LET), passive radiation dosimetry and spectrometry is needed for the purpose of accurate determination of equivalent doses and assessment of health risks to astronauts on long duration missions. Progress in the following research areas is summerized: intercomparisons of cosmic ray equivalent dose and LET spectra measurements between STS missions and between astronauts; increases LET spectra measurement accuracy with ATAS; space radiation measurements for intercomparisons of passive (PNTD, TLD, TRND, Emulsion) and active (TEPC, RME-111) dosimeters; interaction of cosmic ray particles with nuclei in matter; radiation measurements after long duration space exposures; ground based dosimeter calibrations; neutron detector calibrations; radiation measurements on Soviet/Russian spacecraft; space radiation measurements under thin shielding; and space radiation.

  18. METHOD AND MEANS FOR RADIATION DOSIMETRY

    DOEpatents

    Schulte, J.W.; Suttle, J.F.

    1960-10-11

    A precise dosimeter for and x radiations is designed in which a reproducible response to radiation is achieved by controlling the amount of sensitizer. The sensitizer is present in a halogenated hydrocarbon system and is a leuco base of certain dyestuffs. This patent is related to U. S. Patent No. 2,824,234. (D.L.C.)

  19. Method and means for radiation dosimetry

    DOEpatents

    Shulte, J. W.; Suttle, J. F.

    1960-10-18

    A precise dosimeter for and x radiations is designed in which a reproducible response to radiation is achieved by controlling the amount of sensitizer. The sensitizer is present in a halogenated hydrocarbon system and is a leuco base of certain dyestuffs. This patent is related to U. S. Patent No. 2,824,234. (D.L.C.)

  20. Dosimetry of occupational exposure to RF radiation: Measurements and methods

    SciTech Connect

    Tofani, S.; Agnesod, G.

    1987-06-01

    Workers engaged in the operation of RF industrial devices are exposed to electromagnetic radiation in the near-field zone that is characterized by high spatial and temporal gradients. This paper is concerned with measurement methods and data analyses which allow the evaluation of the electromagnetic field exposure of the operator together with the SAR induced by near-field exposure accounting for the spatial and temporal variations. These methods are applied to the theoretical dosimetry of the occupational exposure to RF radiation emitted by 27.12-MHz plastic sealers. The data obtained are compared with those deducible through a conventional wide-band isotropic field meter.

  1. A practical three-dimensional dosimetry system for radiation therapy.

    PubMed

    Guo, Pengyi; Adamovics, John; Oldham, Mark

    2006-10-01

    There is a pressing need for a practical three-dimensional (3D) dosimetry system, convenient for clinical use, and with the accuracy and resolution to enable comprehensive verification of the complex dose distributions typical of modern radiation therapy. Here we introduce a dosimetry system that can achieve this challenge, consisting of a radiochromic dosimeter (PRESAGE) and a commercial optical computed tomography (CT) scanning system (OCTOPUS). PRESAGE is a transparent material with compelling properties for dosimetry, including insensitivity of the dose response to atmospheric exposure, a solid texture negating the need for an external container (reducing edge effects), and amenability to accurate optical CT scanning due to radiochromic optical contrast as opposed to light-scattering contrast. An evaluation of the performance and viability of the PRESAGE/OCTOPUS, combination for routine clinical 3D dosimetry is presented. The performance of the two components (scanner and dosimeter) was investigated separately prior to full system test. The optical CT scanner has a spatial resolution of < or = 1 mm, geometric accuracy within 1 mm, and high reconstruction linearity (with a R2 value of 0.9979 and a standard error of estimation of approximately 1%) relative to independent measurement. The overall performance of the PRESAGE/OCTOPUS system was evaluated with respect to a simple known 3D dose distribution, by comparison with GAFCHROMIC EBT film and the calculated dose from a commissioned planning system. The "measured" dose distribution in a cylindrical PRESAGE dosimeter (16 cm diameter and 11 cm height) was determined by optical-CT, using a filtered backprojection reconstruction algorithm. A three-way Gamma map comparison (4% dose difference and 4 mm distance to agreement), between the PRESAGE, EBT and calculated dose distributions, showed full agreement in measurable region of PRESAGE dosimeter (approximately 90% of radius). The EBT and PRESAGE distributions agreed

  2. A practical three-dimensional dosimetry system for radiation therapy.

    PubMed

    Guo, Pengyi; Adamovics, John; Oldham, Mark

    2006-10-01

    There is a pressing need for a practical three-dimensional (3D) dosimetry system, convenient for clinical use, and with the accuracy and resolution to enable comprehensive verification of the complex dose distributions typical of modern radiation therapy. Here we introduce a dosimetry system that can achieve this challenge, consisting of a radiochromic dosimeter (PRESAGE) and a commercial optical computed tomography (CT) scanning system (OCTOPUS). PRESAGE is a transparent material with compelling properties for dosimetry, including insensitivity of the dose response to atmospheric exposure, a solid texture negating the need for an external container (reducing edge effects), and amenability to accurate optical CT scanning due to radiochromic optical contrast as opposed to light-scattering contrast. An evaluation of the performance and viability of the PRESAGE/OCTOPUS, combination for routine clinical 3D dosimetry is presented. The performance of the two components (scanner and dosimeter) was investigated separately prior to full system test. The optical CT scanner has a spatial resolution of < or = 1 mm, geometric accuracy within 1 mm, and high reconstruction linearity (with a R2 value of 0.9979 and a standard error of estimation of approximately 1%) relative to independent measurement. The overall performance of the PRESAGE/OCTOPUS system was evaluated with respect to a simple known 3D dose distribution, by comparison with GAFCHROMIC EBT film and the calculated dose from a commissioned planning system. The "measured" dose distribution in a cylindrical PRESAGE dosimeter (16 cm diameter and 11 cm height) was determined by optical-CT, using a filtered backprojection reconstruction algorithm. A three-way Gamma map comparison (4% dose difference and 4 mm distance to agreement), between the PRESAGE, EBT and calculated dose distributions, showed full agreement in measurable region of PRESAGE dosimeter (approximately 90% of radius). The EBT and PRESAGE distributions agreed

  3. A practical three-dimensional dosimetry system for radiation therapy

    SciTech Connect

    Guo Pengyi; Adamovics, John; Oldham, Mark

    2006-10-15

    There is a pressing need for a practical three-dimensional (3D) dosimetry system, convenient for clinical use, and with the accuracy and resolution to enable comprehensive verification of the complex dose distributions typical of modern radiation therapy. Here we introduce a dosimetry system that can achieve this challenge, consisting of a radiochromic dosimeter (PRESAGE trade mark sign ) and a commercial optical computed tomography (CT) scanning system (OCTOPUS trade mark sign ). PRESAGE trade mark sign is a transparent material with compelling properties for dosimetry, including insensitivity of the dose response to atmospheric exposure, a solid texture negating the need for an external container (reducing edge effects), and amenability to accurate optical CT scanning due to radiochromic optical contrast as opposed to light-scattering contrast. An evaluation of the performance and viability of the PRESAGE trade mark sign /OCTOPUS, combination for routine clinical 3D dosimetry is presented. The performance of the two components (scanner and dosimeter) was investigated separately prior to full system test. The optical CT scanner has a spatial resolution of {<=}1 mm, geometric accuracy within 1 mm, and high reconstruction linearity (with a R{sup 2} value of 0.9979 and a standard error of estimation of {approx}1%) relative to independent measurement. The overall performance of the PRESAGE trade mark sign /OCTOPUS system was evaluated with respect to a simple known 3D dose distribution, by comparison with GAFCHROMIC[reg] EBT film and the calculated dose from a commissioned planning system. The 'measured' dose distribution in a cylindrical PRESAGE trade mark sign dosimeter (16 cm diameter and 11 cm height) was determined by optical-CT, using a filtered backprojection reconstruction algorithm. A three-way Gamma map comparison (4% dose difference and 4 mm distance to agreement), between the PRESAGE trade mark sign , EBT and calculated dose distributions, showed full

  4. KCl:Dy phosphor for thermoluminescence dosimetry of ionizing radiation.

    PubMed

    Bhujbal, P M; Dhoble, S J

    2013-01-01

    The thermoluminescence (TL) characterizations of γ-irradiated KCl:Dy phosphor for radiation dosimetry are reported. All phosphors were synthesized via a wet chemical route. Minimum fading of TL intensity is recorded in the prepared material. TL in samples containing different concentrations of Dy impurity was studied at different γ-irradiation doses. Peak TL intensities varied sublinearly with γ-ray dose in all samples, but were linear between 0.08 to 0.75 kGy for the KCl:Dy (0.1 mol%) sample. This material may be useful for dosimetry within this range of γ-ray dose. TL peak height was found to be dependant on the concentration (0.05-0.5 mol%) of added Dy in the host.

  5. Effect of respiratory motion on internal radiation dosimetry

    SciTech Connect

    Xie, Tianwu; Zaidi, Habib

    2014-11-01

    Purpose: Estimation of the radiation dose to internal organs is essential for the assessment of radiation risks and benefits to patients undergoing diagnostic and therapeutic nuclear medicine procedures including PET. Respiratory motion induces notable internal organ displacement, which influences the absorbed dose for external exposure to radiation. However, to their knowledge, the effect of respiratory motion on internal radiation dosimetry has never been reported before. Methods: Thirteen computational models representing the adult male at different respiratory phases corresponding to the normal respiratory cycle were generated from the 4D dynamic XCAT phantom. Monte Carlo calculations were performed using the MCNP transport code to estimate the specific absorbed fractions (SAFs) of monoenergetic photons/electrons, the S-values of common positron-emitting radionuclides (C-11, N-13, O-15, F-18, Cu-64, Ga-68, Rb-82, Y-86, and I-124), and the absorbed dose of {sup 18}F-fluorodeoxyglucose ({sup 18}F-FDG) in 28 target regions for both the static (average of dynamic frames) and dynamic phantoms. Results: The self-absorbed dose for most organs/tissues is only slightly influenced by respiratory motion. However, for the lung, the self-absorbed SAF is about 11.5% higher at the peak exhale phase than the peak inhale phase for photon energies above 50 keV. The cross-absorbed dose is obviously affected by respiratory motion for many combinations of source-target pairs. The cross-absorbed S-values for the heart contents irradiating the lung are about 7.5% higher in the peak exhale phase than the peak inhale phase for different positron-emitting radionuclides. For {sup 18}F-FDG, organ absorbed doses are less influenced by respiratory motion. Conclusions: Respiration-induced volume variations of the lungs and the repositioning of internal organs affect the self-absorbed dose of the lungs and cross-absorbed dose between organs in internal radiation dosimetry. The dynamic

  6. Dosimetry in the space radiation field.

    PubMed

    Reitz, G; Beaujean, R; Heckeley, N; Obe, G

    1993-09-01

    The results of dosimetric measurements are presented which were performed as part of a German experiment package flown onboard the Russian space station MIR. These results are compared to those of previous missions: the first United States Spacelab mission and the first German Spacelab mission. Detector packages consisting of plastic nuclear track detectors, nuclear emulsions, and thermoluminescence dosimeters were exposed in different sections of the Russian space station. The equivalent dose for the astronauts was calculated from the measurements to be 3.9 mSv. Before and after the flight venous blood was taken from the astronauts. Chromosomal aberrations in peripheral lymphocytes were analyzed. It was found that the radiation exposure during the spaceflight leads to an elevation of dicentric chromosomes, indicating a radiation burden of the astronauts.

  7. Mixed-radiation-field dosimetry utilizing Nuclear Quadrupole Resonance

    SciTech Connect

    Hintenlang, D.E.; Jamil, K.; Iselin, L.H.

    1992-01-01

    Radiation effects on urea, thiourea, guanidine carbonate and guanine sulfate were evaluated for both photon and neutron irradiations. Hydration of these materials typically provides a greatly increased sensitivity to both forms of radiation exposure, although not all materials lend themselves to this treatment without changing the chemical structure of the compound. Urea was found to be the most stable hydrated compound and provides the best sensitivity for quantifying radiation effects using NQR techniques. Urea permits a straight-forward quantification of each of the important parameters of the observed NQR signal, the FID. Several advanced data analysis methods were developed to assist in quantifying NQR spectra, both from urea and materials having more complex molecular structures, such as thiourea and guanidine sulfate. Unfortunately, these analysis techniques are frequently quite time consuming for the complex NQR spectra that result from some of these materials. The simpler analysis afforded by urea has therefore made it the prime candidate for an NQR dosimetry material. The moderate sensitivity of hydrated urea to photon irradiation does not permit this material to achieve the levels of performance required for a personnel dosimeter. It does, however, demonstrate acceptable sensitivity over dose ranges where it could provide a good biological dosimeter for several areas of radiation processing. The demonstrated photon sensitivity could permit hydrated urea to be used in applications such as food irradiation dosimetry. This material also exhibits a good sensitivity to neutron irradiation. The precise correlation between neutron exposure and the parameters of the resulting NQR spectra are currently being developed.

  8. Radiation damage aspects of the chernobyl accident

    NASA Astrophysics Data System (ADS)

    Parmentier, N.; Nenot, J. C.

    During the night of 25 to 26 April 1986, the most severe nuclear accident occurred at the Chernobyl power station, about 150km north of Kiev, in the Ukraine. It resulted in the irradiation of 237 workers at dose levels justifying medical care. The most severe cases (115) were hospitalized in Moscow, with 20 patients with doses higher than 6 Gy. In most cases, the treatment was classical, based on transfusion of red cells and platelets, and heavy supportive therapy. For 19 patients with severe aplasia, transplantations of bone marrow (13) or foetal liver (6) were decided. Of these patients only one survived, which justifies the statement from U.S.S.R. physicians: after an accident the indications of grafting are limited and its risks may not justify its use. Most of the complications were related to radiation burns which involved 56 victims and resulted in fatal outcomes in at least 19 patients. The population was evacuated from a 30 km zone around the site; based on direct measurements and calculations, the collective dose was evaluated at 1.6 × 10 4 man Sv, with an individual average lower than 250 mSv. The European part of U.S.S.R. with 75 million persons is supposed to have received a collective dose likely to increase the natural mortality by less than 0.1%. The numbers with cancer in the Northern Hemisphere might increase by 0.004% over the next 50 years.

  9. Fiber-optic Cerenkov radiation sensor for proton therapy dosimetry.

    PubMed

    Jang, Kyoung Won; Yoo, Wook Jae; Shin, Sang Hun; Shin, Dongho; Lee, Bongsoo

    2012-06-18

    In proton therapy dosimetry, a fiber-optic radiation sensor incorporating a scintillator must undergo complicated correction processes due to the quenching effect of the scintillator. To overcome the drawbacks of the fiber-optic radiation sensor, we proposed an innovative method using the Cerenkov radiation generated in plastic optical fibers. In this study, we fabricated a fiber-optic Cerenkov radiation sensor without an organic scintillator to measure Cerenkov radiation induced by therapeutic proton beams. Bragg peaks and spread-out Bragg peaks of proton beams were measured using the fiber-optic Cerenkov radiation sensor and the results were compared with those of an ionization chamber and a fiber-optic radiation sensor incorporating an organic scintillator. From the results, we could obtain the Bragg peak and the spread-out Bragg peak of proton beams without quenching effects induced by the scintillator, and these results were in good agreement with those of the ionization chamber. We also measured the Cerenkov radiation generated from the fiber-optic Cerenkov radiation sensor as a function of the dose rate of the proton beam.

  10. Radiation Dosimetry via Automated Fluorescence Microscopy

    NASA Technical Reports Server (NTRS)

    Castleman, Kenneth R.; Schulze, Mark

    2005-01-01

    A developmental instrument for assessment of radiation-induced damage in human lymphocytes includes an automated fluorescence microscope equipped with a one or more chargecoupled- device (CCD) video camera(s) and circuitry to digitize the video output. The microscope is also equipped with a three-axis translation stage that includes a rotation stage, and a rotary tray that holds as many as thirty specimen slides. The figure depicts one version of the instrument. Once the slides have been prepared and loaded into the tray, the instrument can operate unattended. A computer controls the operation of the stage, tray, and microscope, and processes the digital fluorescence-image data to recognize and count chromosomes that have been broken, presumably by radiation. The design and method of operation of the instrument exploit fluorescence in situ hybridization (FISH) of metaphase chromosome spreads, which is a technique that has been found to be valuable for monitoring the radiation dose to circulating lymphocytes. In the specific FISH protocol used to prepare specimens for this instrument, metaphase lymphocyte cultures are chosen for high mitotic index and highly condensed chromosomes, then several of the largest chromosomes are labeled with three of four differently colored whole-chromosome-staining dyes. The three dyes, which are used both individually and in various combinations, are fluorescein isothiocyanate (FITC), Texas Red (or equivalent), and Cy5 (or equivalent); The fourth dye 4',6-diamidino- 2-phenylindole (DAPI) is used as a counterstain. Under control by the computer, the microscope is automatically focused on the cells and each slide is scanned while the computer analyzes the DAPI-fluorescence images to find the metaphases. Each metaphase field is recentered in the field of view and refocused. Then a four-color image (more precisely, a set of images of the same view in the fluorescent colors of the four dyes) is acquired. By use of pattern

  11. Applications of Cherenkov Light Emission for Dosimetry in Radiation Therapy

    NASA Astrophysics Data System (ADS)

    Glaser, Adam Kenneth

    Since its discovery in the 1930's, the Cherenkov effect has been paramount in the development of high-energy physics research. It results in light emission from charged particles traveling faster than the local speed of light in a dielectric medium. The ability of this emitted light to describe a charged particle's trajectory, energy, velocity, and mass has allowed scientists to study subatomic particles, detect neutrinos, and explore the properties of interstellar matter. However, only recently has the phenomenon been considered in the practical context of medical physics and radiation therapy dosimetry, where Cherenkov light is induced by clinical x-ray photon, electron, and proton beams. To investigate the relationship between this phenomenon and dose deposition, a Monte Carlo plug-in was developed within the Geant4 architecture for medically-oriented simulations (GAMOS) to simulate radiation-induced optical emission in biological media. Using this simulation framework, it was determined that Cherenkov light emission may be well suited for radiation dosimetry of clinically used x-ray photon beams. To advance this application, several novel techniques were implemented to realize the maximum potential of the signal, such as time-gating for maximizing the signal to noise ratio (SNR) and Cherenkov-excited fluorescence for generating isotropic light release in water. Proof of concept experiments were conducted in water tanks to demonstrate the feasibility of the proposed method for two-dimensional (2D) projection imaging, three-dimensional (3D) parallel beam tomography, large field of view 3D cone beam tomography, and video-rate dynamic imaging of treatment plans for a number of common radiotherapy applications. The proposed dosimetry method was found to have a number of unique advantages, including but not limited to its non-invasive nature, water-equivalence, speed, high-resolution, ability to provide full 3D data, and potential to yield data in-vivo. Based on

  12. Radiation accidents and nuclear energy: medical consequences and therapy.

    PubMed

    Champlin, R E; Kastenberg, W E; Gale, R P

    1988-11-01

    After the accidents at Chernobyl, the Soviet Union, and in Goiania, Brazil, there is increasing concern about the medical risks from radiation accidents. This overview summarizes the principles of nuclear energy, the biologic effects of accidental radiation exposure, the emergency response to nuclear accidents, and approaches to treating radiation injuries. Also discussed are the related issues of reactor safety, the disposal of radioactive waste, and the proliferation of nuclear weapons. With the increasing use of radioactive materials for power, weapons, and medical diagnostics, the medical community needs to understand the health consequences of radiation exposure.

  13. Radiation Dosimetry Study in Dental Enamel of Human Tooth Using Electron Paramagnetic Resonance

    NASA Astrophysics Data System (ADS)

    De, Tania; Romanyukha, Alex; Pass, Barry; Misra, Prabhakar

    2009-07-01

    Electron paramagnetic resonance (EPR) dosimetry of tooth enamel is used for individual dose reconstruction following radiation accidents. The purpose of this study is to develop a rapid, minimally invasive technique of obtaining a sample of dental enamel small enough to not disturb the structure and functionality of a tooth and to improve the sensitivity of the spectral signals using X-band (9.4 GHz) and Q-band (34 GHz) EPR technique. In this study EPR measurements in X-band were performed on 100 mg isotropic powdered enamel samples and Q-band was performed on 4 mg, 1×1×3 mm enamel biopsy samples. All samples were obtained from discarded teeth collected during normal dental treatment. To study the variation of the Radiation-Induced Signal (RIS) at different orientations in the applied magnetic field, samples were placed in the resonance cavity for Q-band EPR. X-band EPR measurements were performed on 100 mg isotropic powdered enamel samples. In X-band spectra, the RIS is distinct from the "native" radiation-independent signal only for doses >0.5 Gy. Q-band, however, resolves the RIS and "native" signals and improves sensitivity by a factor of 20, enabling measurements in 2-4 mg tooth enamel samples, as compared to 100 mg for X-band. The estimated lower limit of Q-band dose measurement is 0.5 Gy. Q-band EPR enamel dosimetry results in greater sensitivity and smaller sample size through enhanced spectral resolution. Thus, this can be a valuable technique for population triage in the event of detonation of a radiation dispersal device ("dirty" bomb) or other radiation event with massive casualties. Further, the small 4 mg samples can be obtained by a minimally-invasive biopsy technique.

  14. Space radiation dosimetry in low-Earth orbit and beyond.

    PubMed

    Benton, E R; Benton, E V

    2001-09-01

    Space radiation dosimetry presents one of the greatest challenges in the discipline of radiation protection. This is a result of both the highly complex nature of the radiation fields encountered in low-Earth orbit (LEO) and interplanetary space and of the constraints imposed by spaceflight on instrument design. This paper reviews the sources and composition of the space radiation environment in LEO as well as beyond the Earth's magnetosphere. A review of much of the dosimetric data that have been gathered over the last four decades of human space flight is presented. The different factors affecting the radiation exposures of astronauts and cosmonauts aboard the International Space Station (ISS) are emphasized. Measurements made aboard the Mir Orbital Station have highlighted the importance of both secondary particle production within the structure of spacecraft and the effect of shielding on both crew dose and dose equivalent. Roughly half the dose on ISS is expected to come from trapped protons and half from galactic cosmic rays (GCRs). The dearth of neutron measurements aboard LEO spacecraft and the difficulty inherent in making such measurements have led to large uncertainties in estimates of the neutron contribution to total dose equivalent. Except for a limited number of measurements made aboard the Apollo lunar missions, no crew dosimetry has been conducted beyond the Earth's magnetosphere. At the present time we are forced to rely on model-based estimates of crew dose and dose equivalent when planning for interplanetary missions, such as a mission to Mars. While space crews in LEO are unlikely to exceed the exposure limits recommended by such groups as the NCRP, dose equivalents of the same order as the recommended limits are likely over the course of a human mission to Mars.

  15. Space radiation dosimetry in low-Earth orbit and beyond.

    PubMed

    Benton, E R; Benton, E V

    2001-09-01

    Space radiation dosimetry presents one of the greatest challenges in the discipline of radiation protection. This is a result of both the highly complex nature of the radiation fields encountered in low-Earth orbit (LEO) and interplanetary space and of the constraints imposed by spaceflight on instrument design. This paper reviews the sources and composition of the space radiation environment in LEO as well as beyond the Earth's magnetosphere. A review of much of the dosimetric data that have been gathered over the last four decades of human space flight is presented. The different factors affecting the radiation exposures of astronauts and cosmonauts aboard the International Space Station (ISS) are emphasized. Measurements made aboard the Mir Orbital Station have highlighted the importance of both secondary particle production within the structure of spacecraft and the effect of shielding on both crew dose and dose equivalent. Roughly half the dose on ISS is expected to come from trapped protons and half from galactic cosmic rays (GCRs). The dearth of neutron measurements aboard LEO spacecraft and the difficulty inherent in making such measurements have led to large uncertainties in estimates of the neutron contribution to total dose equivalent. Except for a limited number of measurements made aboard the Apollo lunar missions, no crew dosimetry has been conducted beyond the Earth's magnetosphere. At the present time we are forced to rely on model-based estimates of crew dose and dose equivalent when planning for interplanetary missions, such as a mission to Mars. While space crews in LEO are unlikely to exceed the exposure limits recommended by such groups as the NCRP, dose equivalents of the same order as the recommended limits are likely over the course of a human mission to Mars. PMID:11863032

  16. Recent developments of optically stimulated luminescence materials and techniques for radiation dosimetry and clinical applications

    PubMed Central

    Pradhan, A. S.; Lee, J. I.; Kim, J. L.

    2008-01-01

    During the last 10 years, optically stimulated luminescence (OSL) has emerged as a formidable competitor not only to thermoluminescence dosimetry (TLD) but also to several other dosimetry systems. Though a large number of materials have been synthesized and studied for OSL, Al2O3:C continues to dominate the dosimetric applications. Re-investigations of OSL in BeOindicate that this material might provide an alternative to Al2O3:C. Study of OSL of electronic components of mobile phones and ID cards appears to have opened up a feasibility of dosimetry and dose reconstruction using the electronic components of gadgets of everyday use in the events of unforeseen situations of radiological accidents, including the event of a dirty bomb by terrorist groups. Among the newly reported materials, a very recent development of NaMgF3:Eu2+ appears fascinating because of its high OSL sensitivity and tolerable tissue equivalence. In clinical dosimetry, an OSL as a passive dosimeter could do all that TLD can do, much faster with a better or at least the same efficiency; and in addition, it provides a possibility of repeated readout unlike TLD, in which all the dose information is lost in a single readout. Of late, OSL has also emerged as a practical real-time dosimeter for in vivo measurements in radiation therapy (for both external beams and brachytherapy) and in various diagnostic radiological examinations including mammography and CT dosimetry. For in vivo measurements, a probe of Al2O3:C of size of a fraction of a millimeter provides the information on both the dose rate and the total dose from the readout of radioluminescence and OSL signals respectively, from the same probe. The availability of OSL dosimeters in various sizes and shapes and their performance characteristics as compared to established dosimeters such as plastic scintillation dosimeters, diode detectors, MOSFET detectors, radiochromic films, etc., shows that OSL may soon become the first choice for point dose

  17. Recent developments of optically stimulated luminescence materials and techniques for radiation dosimetry and clinical applications.

    PubMed

    Pradhan, A S; Lee, J I; Kim, J L

    2008-07-01

    During the last 10 years, optically stimulated luminescence (OSL) has emerged as a formidable competitor not only to thermoluminescence dosimetry (TLD) but also to several other dosimetry systems. Though a large number of materials have been synthesized and studied for OSL, Al(2)O(3):C continues to dominate the dosimetric applications. Re-investigations of OSL in BeOindicate that this material might provide an alternative to Al(2)O(3):C. Study of OSL of electronic components of mobile phones and ID cards appears to have opened up a feasibility of dosimetry and dose reconstruction using the electronic components of gadgets of everyday use in the events of unforeseen situations of radiological accidents, including the event of a dirty bomb by terrorist groups. Among the newly reported materials, a very recent development of NaMgF(3):Eu(2+) appears fascinating because of its high OSL sensitivity and tolerable tissue equivalence. In clinical dosimetry, an OSL as a passive dosimeter could do all that TLD can do, much faster with a better or at least the same efficiency; and in addition, it provides a possibility of repeated readout unlike TLD, in which all the dose information is lost in a single readout. Of late, OSL has also emerged as a practical real-time dosimeter for in vivo measurements in radiation therapy (for both external beams and brachytherapy) and in various diagnostic radiological examinations including mammography and CT dosimetry. For in vivo measurements, a probe of Al(2)O(3):C of size of a fraction of a millimeter provides the information on both the dose rate and the total dose from the readout of radioluminescence and OSL signals respectively, from the same probe. The availability of OSL dosimeters in various sizes and shapes and their performance characteristics as compared to established dosimeters such as plastic scintillation dosimeters, diode detectors, MOSFET detectors, radiochromic films, etc., shows that OSL may soon become the first choice

  18. Recent developments of optically stimulated luminescence materials and techniques for radiation dosimetry and clinical applications.

    PubMed

    Pradhan, A S; Lee, J I; Kim, J L

    2008-07-01

    During the last 10 years, optically stimulated luminescence (OSL) has emerged as a formidable competitor not only to thermoluminescence dosimetry (TLD) but also to several other dosimetry systems. Though a large number of materials have been synthesized and studied for OSL, Al(2)O(3):C continues to dominate the dosimetric applications. Re-investigations of OSL in BeOindicate that this material might provide an alternative to Al(2)O(3):C. Study of OSL of electronic components of mobile phones and ID cards appears to have opened up a feasibility of dosimetry and dose reconstruction using the electronic components of gadgets of everyday use in the events of unforeseen situations of radiological accidents, including the event of a dirty bomb by terrorist groups. Among the newly reported materials, a very recent development of NaMgF(3):Eu(2+) appears fascinating because of its high OSL sensitivity and tolerable tissue equivalence. In clinical dosimetry, an OSL as a passive dosimeter could do all that TLD can do, much faster with a better or at least the same efficiency; and in addition, it provides a possibility of repeated readout unlike TLD, in which all the dose information is lost in a single readout. Of late, OSL has also emerged as a practical real-time dosimeter for in vivo measurements in radiation therapy (for both external beams and brachytherapy) and in various diagnostic radiological examinations including mammography and CT dosimetry. For in vivo measurements, a probe of Al(2)O(3):C of size of a fraction of a millimeter provides the information on both the dose rate and the total dose from the readout of radioluminescence and OSL signals respectively, from the same probe. The availability of OSL dosimeters in various sizes and shapes and their performance characteristics as compared to established dosimeters such as plastic scintillation dosimeters, diode detectors, MOSFET detectors, radiochromic films, etc., shows that OSL may soon become the first choice

  19. Sandia National Laboratories results for the 2010 criticality accident dosimetry exercise, at the CALIBAN reactor, CEA Valduc France.

    SciTech Connect

    Ward, Dann C.

    2011-09-01

    This document describes the personal nuclear accident dosimeter (PNAD) used by Sandia National Laboratories (SNL) and presents PNAD dosimetry results obtained during the Nuclear Accident Dosimeter Intercomparison Study held 20-23 September, 2010, at CEA Valduc, France. SNL PNADs were exposed in two separate irradiations from the CALIBAN reactor. Biases for reported neutron doses ranged from -15% to +0.4% with an average bias of -7.7%. PNADs were also exposed on the back side of phantoms to assess orientation effects.

  20. Environmental aftermath of the radiation accident at Tomsk-7

    SciTech Connect

    Porfiriev, B.N. |

    1996-01-01

    An analysis is presented of the environmental effects of the most serious radiation accident recorded after Chernobyl, which occurred in the formerly secret town of Tomsk-7 in Siberia, Russia, on 6, April 1993. Fortunately, it appears not to have become a major industrial crisis or disaster. The causes of the accident are described. It is argued that a mixture of both objective and subjective prerequisites, including specific human, organizational, and technological factors, were responsible for the explosion or directly facilitated it. The Tomsk-7 accident`s ecological, medical, social, and psychological consequences are discussed. 33 refs., 1 figs., 1 tab.

  1. Radiation Dosimetry of Dental Enamel Using X-Band and Q-Band EPR Spectroscopy

    NASA Astrophysics Data System (ADS)

    de, Tania; Romanyukha, Alex; Pass, Barry; Misra, Prabhakar

    2010-02-01

    Electron paramagnetic resonance (EPR) dosimetry of tooth enamel can be used for individual dose reconstruction following radiation accidents. The purpose of this study was to develop a rapid, minimally invasive technique for obtaining a sample of dental enamel small enough to not disturb the structure and functionality of a tooth and to improve the sensitivity of the spectral signals using X-band (9.4 GHz) and Q-band (34 GHz) EPR spectroscopy. EPR measurements in X-band were performed on 100 mg isotropic powdered enamel samples and Q-band measurements done on 4 mg (1x1x3 mm) enamel biopsy samples. All samples were obtained from discarded teeth collected during normal dental treatment. In order to study the variation of the Radiation-Induced Signal (RIS) at different orientations in the applied magnetic field samples were placed in the resonance cavity for Q-band EPR. In X-band spectra, the RIS is distinct from the ``native'' radiation-independent signal only for doses > 0.5Gy. Q-band, however, resolves the RIS and ``native'' signals and improves sensitivity by a factor of 20 enabling measurements in 2-4 mg tooth enamel samples. )

  2. A semiconductor radiation imaging pixel detector for space radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Kroupa, Martin; Bahadori, Amir; Campbell-Ricketts, Thomas; Empl, Anton; Hoang, Son Minh; Idarraga-Munoz, John; Rios, Ryan; Semones, Edward; Stoffle, Nicholas; Tlustos, Lukas; Turecek, Daniel; Pinsky, Lawrence

    2015-07-01

    Progress in the development of high-performance semiconductor radiation imaging pixel detectors based on technologies developed for use in high-energy physics applications has enabled the development of a completely new generation of compact low-power active dosimeters and area monitors for use in space radiation environments. Such detectors can provide real-time information concerning radiation exposure, along with detailed analysis of the individual particles incident on the active medium. Recent results from the deployment of detectors based on the Timepix from the CERN-based Medipix2 Collaboration on the International Space Station (ISS) are reviewed, along with a glimpse of developments to come. Preliminary results from Orion MPCV Exploration Flight Test 1 are also presented.

  3. A semiconductor radiation imaging pixel detector for space radiation dosimetry.

    PubMed

    Kroupa, Martin; Bahadori, Amir; Campbell-Ricketts, Thomas; Empl, Anton; Hoang, Son Minh; Idarraga-Munoz, John; Rios, Ryan; Semones, Edward; Stoffle, Nicholas; Tlustos, Lukas; Turecek, Daniel; Pinsky, Lawrence

    2015-07-01

    Progress in the development of high-performance semiconductor radiation imaging pixel detectors based on technologies developed for use in high-energy physics applications has enabled the development of a completely new generation of compact low-power active dosimeters and area monitors for use in space radiation environments. Such detectors can provide real-time information concerning radiation exposure, along with detailed analysis of the individual particles incident on the active medium. Recent results from the deployment of detectors based on the Timepix from the CERN-based Medipix2 Collaboration on the International Space Station (ISS) are reviewed, along with a glimpse of developments to come. Preliminary results from Orion MPCV Exploration Flight Test 1 are also presented. PMID:26256630

  4. Radiation dosimetry of a conformal heat-brachytherapy applicator.

    PubMed

    Taschereau, Richard; Stauffer, Paul R; Hsu, I-Chow; Schlorff, Jaime L; Milligan, Andrew J; Pouliot, Jean

    2004-08-01

    The purpose of this paper is to report the radiation dosimetric characteristics of a new combination applicator for delivering heat and radiation simultaneously to large area superficial disease <1.5 cm deep. The applicator combines an array of brachytherapy catheters (for radiation delivery) with a conformal printed circuit board microwave antenna array (for heat generation), and a body-conforming 5-10 mm thick temperature-controlled water bolus. The rationale for applying both modalities simultaneously includes the potential for significantly higher response rate due to enhanced synergism of modalities, and lower peak toxicity due to temporal extension of heat and radiation induced toxicities. Treatment plans and radiation dosimetry are calculated with IPSA (an optimization tool developed at UCSF) for 15 x 15 cm(2) and 35 x 24 cm(2) applicators, lesion thicknesses of 5 to 15 mm, flat and curved surfaces, and catheter separation of 5 and 10 mm. The effect on skin dose of bolus thickness and presence of thin copper antenna structures between radiation source and tissue are also evaluated. Results demonstrate the ability of the applicator to provide conformal radiation dose coverage for up to 15 mm deep target volumes under the applicator. For clinically acceptable plans, tumor coverage is > 98%, homogeneity index > 0.95 and the percentage of normal tissue irradiated is < 20%. The dose gradient at the skin surface varies from 3 to 5 cGy/mm depending on bolus thickness and lesion depth. Attenuation of the photon beam by the printed circuit antenna array is of the order 0.25% and secondary electron emissions are absorbed completely within 5 mm of water bolus and plastic layers. Both phenomena can then be neglected in dose calculations allowing commercial software to be used for treatment planning. This novel applicator should prove useful for the treatment of diffuse chestwall disease located over contoured anatomy that may be difficult to treat with single field

  5. Radiation dosimetry of a conformal heat-brachytherapy applicator.

    PubMed

    Taschereau, Richard; Stauffer, Paul R; Hsu, I-Chow; Schlorff, Jaime L; Milligan, Andrew J; Pouliot, Jean

    2004-08-01

    The purpose of this paper is to report the radiation dosimetric characteristics of a new combination applicator for delivering heat and radiation simultaneously to large area superficial disease <1.5 cm deep. The applicator combines an array of brachytherapy catheters (for radiation delivery) with a conformal printed circuit board microwave antenna array (for heat generation), and a body-conforming 5-10 mm thick temperature-controlled water bolus. The rationale for applying both modalities simultaneously includes the potential for significantly higher response rate due to enhanced synergism of modalities, and lower peak toxicity due to temporal extension of heat and radiation induced toxicities. Treatment plans and radiation dosimetry are calculated with IPSA (an optimization tool developed at UCSF) for 15 x 15 cm(2) and 35 x 24 cm(2) applicators, lesion thicknesses of 5 to 15 mm, flat and curved surfaces, and catheter separation of 5 and 10 mm. The effect on skin dose of bolus thickness and presence of thin copper antenna structures between radiation source and tissue are also evaluated. Results demonstrate the ability of the applicator to provide conformal radiation dose coverage for up to 15 mm deep target volumes under the applicator. For clinically acceptable plans, tumor coverage is > 98%, homogeneity index > 0.95 and the percentage of normal tissue irradiated is < 20%. The dose gradient at the skin surface varies from 3 to 5 cGy/mm depending on bolus thickness and lesion depth. Attenuation of the photon beam by the printed circuit antenna array is of the order 0.25% and secondary electron emissions are absorbed completely within 5 mm of water bolus and plastic layers. Both phenomena can then be neglected in dose calculations allowing commercial software to be used for treatment planning. This novel applicator should prove useful for the treatment of diffuse chestwall disease located over contoured anatomy that may be difficult to treat with single field

  6. [Medical protection during radiation accidents: some results and lessons of the Chernobyl accident].

    PubMed

    Legeza, V I; Grebeniuk, A N; Zatsepin, V V

    2011-01-01

    Actions of medical radiation protection of liquidators of consequences of on Chernobyl atomic power station accident are analysed. It is shown, that during the early period of the accident medical protection of liquidators was provided by administration of radioprotectors, means of prophylaxis: of radioactive iodine incorporation and agent for preventing psychological and emotional stress. When carrying out decontamination and regenerative works, preparations which action is caused by increase of nonspecific resistance of an organism were applied. The lessons taken from the results of the Chernobyl accident, have allowed one to improve the system of medical protection and to introduce in practice new highly effective radioprotective agents.

  7. Standard Practice for Dosimetry of Proton Beams for use in Radiation Effects Testing of Electronics

    SciTech Connect

    McMahan, Margaret A.; Blackmore, Ewart; Cascio, Ethan W.; Castaneda, Carlos; von Przewoski, Barbara; Eisen, Harvey

    2008-07-25

    Representatives of facilities that routinely deliver protons for radiation effect testing are collaborating to establish a set of standard best practices for proton dosimetry. These best practices will be submitted to the ASTM International for adoption.

  8. Genetic and molecular dosimetry of HZE radiation (US-1 RADIAT)

    NASA Technical Reports Server (NTRS)

    Nelson, Gregory A.; Schubert, W. W.; Kazarians, G. A.; Richards, G. F.; Benton, E. V.; Benton, E. R.; Henke, R. P.

    1995-01-01

    In order to estimate radiation exposure in space, experiments were conducted during the 1st International Microgravity Laboratory (IML-1) mission in order to isolate genetic changes in animal cells caused by cosmic rays. The space measurements were evaluated against results from synthetic cosmic rays produced by particle accelerators on the ground. The biological material used was the tiny soil nematode, Caenorhabditis elegans. The measurements were made by thermoluminescent detectors and plastic nuclear track detectors. The development and the chromosome mechanics in microgravity were studied, and the mutagenesis induced by radiation exposure was analyzed. The results showed that there are no obvious differences in the development, behavior and chromosome mechanics, as a function of gravity unloading (reproduction, self-fertilization and mating of males with hermaphrodites, gross anatomy, symmetry and gametogenesis, pairing, disjoining and recombination of chromosomes). A variety of mutants were isolated, and it was noted that mutants isolated from regions of identified high particles were more severely affected than those isolated by random screening. Linear energy transfer particles seem to favor large scale genetic lesions.

  9. Biological dosimetry of ionizing radiation: Evaluation of the dose with cytogenetic methodologies by the construction of calibration curves

    NASA Astrophysics Data System (ADS)

    Zafiropoulos, Demetre; Facco, E.; Sarchiapone, Lucia

    2016-09-01

    In case of a radiation accident, it is well known that in the absence of physical dosimetry biological dosimetry based on cytogenetic methods is a unique tool to estimate individual absorbed dose. Moreover, even when physical dosimetry indicates an overexposure, scoring chromosome aberrations (dicentrics and rings) in human peripheral blood lymphocytes (PBLs) at metaphase is presently the most widely used method to confirm dose assessment. The analysis of dicentrics and rings in PBLs after Giemsa staining of metaphase cells is considered the most valid assay for radiation injury. This work shows that applying the fluorescence in situ hybridization (FISH) technique, using telomeric/centromeric peptide nucleic acid (PNA) probes in metaphase chromosomes for radiation dosimetry, could become a fast scoring, reliable and precise method for biological dosimetry after accidental radiation exposures. In both in vitro methods described above, lymphocyte stimulation is needed, and this limits the application in radiation emergency medicine where speed is considered to be a high priority. Using premature chromosome condensation (PCC), irradiated human PBLs (non-stimulated) were fused with mitotic CHO cells, and the yield of excess PCC fragments in Giemsa stained cells was scored. To score dicentrics and rings under PCC conditions, the necessary centromere and telomere detection of the chromosomes was obtained using FISH and specific PNA probes. Of course, a prerequisite for dose assessment in all cases is a dose-effect calibration curve. This work illustrates the various methods used; dose response calibration curves, with 95% confidence limits used to estimate dose uncertainties, have been constructed for conventional metaphase analysis and FISH. We also compare the dose-response curve constructed after scoring of dicentrics and rings using PCC combined with FISH and PNA probes. Also reported are dose response curves showing scored dicentrics and rings per cell, combining

  10. Impact of the Fukushima nuclear accident on background radiation doses measured by control dosimeters in Japan.

    PubMed

    Romanyukha, Alexander; King, David L; Kennemur, Lisa K

    2012-05-01

    After the 9.0 magnitude earthquake and subsequent massive tsunami on 11 March 2011 in Japan, several reactors at the Fukushima Daiichi Nuclear Power Plant suffered severe damage. There was immediate participation of U.S. Navy vessels and other United States Department of Defense (DoD) teams that were already in the area at the time of the disaster or arrived shortly thereafter. The correct determination of occupational dose equivalent requires estimation of the background dose component measured by control dosimeters, which is subsequently subtracted from the total dose equivalent measured by personal dosimeters. The purpose of the control dosimeters is to determine the amount of radiation dose equivalent that has accumulated on the dosimeter from background or other non-occupational sources while they are in transit or being stored. Given the release of radioactive material and potential exposure to radiation from the Fukushima Daiichi Nuclear Power Plant and the process by which the U.S. Navy calculates occupational exposure to ionizing radiation, analysis of pre- and post-event control dosimeters is warranted. Several hundred historical dose records from the Naval Dosimetry Center (NDC) database were analyzed and compared with the post-accident dose equivalent data of control dosimeters. As result, it was shown that the dose contribution of the radiation and released radiological materials from the Fukushima nuclear accident to background radiation doses is less than 0.375 μSv d for shallow and deep photon dose equivalent. There is no measurable effect on neutron background exposure. The latter has at least two important conclusions. First, the NDC can use doses measured by control dosimeters at issuing sites in Japan for determination of personnel dose equivalents; second, the dose data from control dosimeters prior to and after the Fukushima accident may be used to assist in dose reconstruction of non-radiological (non-badged) personnel at these locations.

  11. GENII: The Hanford Environmental Radiation Dosimetry Software System: Volume 2, Users' manual: Hanford Environmental Dosimetry Upgrade Project

    SciTech Connect

    Napier, B.A.; Peloquin, R.A.; Strenge, D.L.; Ramsdell, J.V.

    1988-11-01

    The Hanford Environmental Dosimetry Upgrade Project was undertaken to incorporate the internal dosimetry models recommended by the International Commission on Radiological Protection (ICRP) in updated versions of the environmental pathway analysis models used at Hanford. The resulting second generation of Hanford environmental dosimetry computer codes is compiled in the Hanford Environmental Dosimetry System (Generation II, or GENII). The purpose of this coupled system of computer codes is to analyze environmental contamination of, air, water, or soil. This is accomplished by calculating radiation doses to individuals or populations. GENII is described in three volumes of documentation. This second volume is a Users' Manual, providing code structure, users' instructions, required system configurations, and QA-related topics. The first volume describes the theoretical considerations of the system. The third volume is a Code Maintenance Manual for the user who requires knowledge of code detail. It includes logic diagrams, global dictionary, worksheets, example hand calculations, and listings of the code and its associated data libraries. 27 refs., 17 figs., 23 tabs.

  12. GENII (Generation II): The Hanford Environmental Radiation Dosimetry Software System: Volume 3, Code maintenance manual: Hanford Environmental Dosimetry Upgrade Project

    SciTech Connect

    Napier, B.A.; Peloquin, R.A.; Strenge, D.L.; Ramsdell, J.V.

    1988-09-01

    The Hanford Environmental Dosimetry Upgrade Project was undertaken to incorporate the internal dosimetry models recommended by the International Commission on Radiological Protection (ICRP) in updated versions of the environmental pathway analysis models used at Hanford. The resulting second generation of Hanford environmental dosimetry computer codes is compiled in the Hanford Environmental Dosimetry System (Generation II, or GENII). This coupled system of computer codes is intended for analysis of environmental contamination resulting from acute or chronic releases to, or initial contamination of, air, water, or soil, on through the calculation of radiation doses to individuals or populations. GENII is described in three volumes of documentation. This volume is a Code Maintenance Manual for the serious user, including code logic diagrams, global dictionary, worksheets to assist with hand calculations, and listings of the code and its associated data libraries. The first volume describes the theoretical considerations of the system. The second volume is a Users' Manual, providing code structure, users' instructions, required system configurations, and QA-related topics. 7 figs., 5 tabs.

  13. LLNL Results from CALIBAN-PROSPERO Nuclear Accident Dosimetry Experiments in September 2014

    SciTech Connect

    Lobaugh, M. L.; Hickman, D. P.; Wong, C. W.; Wysong, A. R.; Merritt, M. J.; Heinrichs, D. P.; Topper, J. D.

    2015-05-21

    Lawrence Livermore National Laboratory (LLNL) uses thin neutron activation foils, sulfur, and threshold energy shielding to determine neutron component doses and the total dose from neutrons in the event of a nuclear criticality accident. The dosimeter also uses a DOELAP accredited Panasonic UD-810 (Panasonic Industrial Devices Sales Company of America, 2 Riverfront Plaza, Newark, NJ 07102, U.S.A.) thermoluminescent dosimetery system (TLD) for determining the gamma component of the total dose. LLNL has participated in three international intercomparisons of nuclear accident dosimeters. In October 2009, LLNL participated in an exercise at the French Commissariat à l’énergie atomique et aux énergies alternatives (Alternative Energies and Atomic Energy Commission- CEA) Research Center at Valduc utilizing the SILENE reactor (Hickman, et.al. 2010). In September 2010, LLNL participated in a second intercomparison at CEA Valduc, this time with exposures at the CALIBAN reactor (Hickman et al. 2011). This paper discusses LLNL’s results of a third intercomparison hosted by the French Institut de Radioprotection et de Sûreté Nucléaire (Institute for Radiation Protection and Nuclear Safety- IRSN) with exposures at two CEA Valduc reactors (CALIBAN and PROSPERO) in September 2014. Comparison results between the three participating facilities is presented elsewhere (Chevallier 2015; Duluc 2015).

  14. OSL studies of alkali fluoroperovskite single crystals for radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Daniel, D. Joseph; Raja, A.; Madhusoodanan, U.; Annalakshmi, O.; Ramasamy, P.

    2016-08-01

    This paper presents a preliminary investigation of the optically stimulated luminescence (OSL) of alkali fluoroperovskite single crystals for radiation dosimetry. The perovskite-like KMgF3, NaMgF3 and LiBaF3 polycrystalline compounds doped with rare earths (Eu2+ and Ce3+) were synthesized by standard solid state reaction technique. Phase purity of the synthesized compounds was analyzed by powder X-ray diffraction technique. Single crystals of these compounds have been grown from melt by using vertical Bridgman-Stockbarger method. The Linearly Modulated OSL and Continuous Wave OSL measurements were performed in these alkali fluorides using blue light stimulation. Thermal bleaching experiments have shown that OSL signals originate from traps which are unstable near 200 °C, thus proving the suitability of the signals for dosimetric purposes. Optical bleaching measurements were also performed for these fluoride samples. OSL dose response was studied as a function of dose which was found to increase with beta dose.

  15. Nuclear data needs for radiation protection and therapy dosimetry

    SciTech Connect

    Chadwick, M.B.; DeLuca, P.M. Jr.; Haight, R.C.

    1995-12-31

    New nuclear data are required for improved neutron and proton radiotherapy treatment planning as well as future applications of high-energy particle accelerators. Modern neutron radiotherapy employs energies extending to 70 MeV, while industrial applications such as transmutation and tritium breeding may generate neutrons exceeding energies of 100 MeV. Secondary neutrons produced by advanced proton therapy facilities can have energies as high as 250 MeV. Each use requires nuclear data for transport calculations and analysis of radiation effects (dosimetry). We discuss the nuclear data needs supportive of these applications including the different information requirements. As data in this energy region are sparse and likely to remain so, advanced nuclear model calculations can provide some of the needed information. ln this context, we present new evaluated nuclear data for C, N, and O. Additional experimental information, including integral and differential data, are required to confirm these results and to bound further calculations. We indicate the required new data to be measured and the difficulties in carrying out such experiments.

  16. Radiation protection and dosimetry issues in the medical applications of ionizing radiation

    NASA Astrophysics Data System (ADS)

    Vaz, Pedro

    2014-11-01

    The technological advances that occurred during the last few decades paved the way to the dissemination of CT-based procedures in radiology, to an increasing number of procedures in interventional radiology and cardiology as well as to new techniques and hybrid modalities in nuclear medicine and in radiotherapy. These technological advances encompass the exposure of patients and medical staff to unprecedentedly high dose values that are a cause for concern due to the potential detrimental effects of ionizing radiation to the human health. As a consequence, new issues and challenges in radiological protection and dosimetry in the medical applications of ionizing radiation have emerged. The scientific knowledge of the radiosensitivity of individuals as a function of age, gender and other factors has also contributed to raising the awareness of scientists, medical staff, regulators, decision makers and other stakeholders (including the patients and the public) for the need to correctly and accurately assess the radiation induced long-term health effects after medical exposure. Pediatric exposures and their late effects became a cause of great concern. The scientific communities of experts involved in the study of the biological effects of ionizing radiation have made a strong case about the need to undertake low dose radiation research and the International System of Radiological Protection is being challenged to address and incorporate issues such as the individual sensitivities, the shape of dose-response relationship and tissue sensitivity for cancer and non-cancer effects. Some of the answers to the radiation protection and dosimetry issues and challenges in the medical applications of ionizing radiation lie in computational studies using Monte Carlo or hybrid methods to model and simulate particle transport in the organs and tissues of the human body. The development of sophisticated Monte Carlo computer programs and voxel phantoms paves the way to an accurate

  17. Space Radiation Dosimetry with the The Radiation Assessment Detector (RAD) on the Mars Science Laboratory (MSL)

    NASA Astrophysics Data System (ADS)

    Hassler, Donald M.; Zeitlin, Cary; Wimmer-Schweingruber, Robert F.; Boehm, Eckhardt; Boettcher, Stephan; Burmeister, Soenke; Cucinotta, Francis A.; Kortmann, Onno; Martin, Cesar; Posner, Arik; Rafkin, Scot; Reitz, Guenther

    The Radiation Assessment Detector (RAD) is a compact, lightweight energetic particle an-alyzer that will fly on the NASA 2011 Mars Science Laboratory (MSL) Mission. RAD will detect and analyze energetic particle species (p, n, He, 2¡Z¡26) relevant for dosimetry on the Martian surface. The Galactic Cosmic Rays and Solar Energetic Particles produce both pri-mary and secondary radiation, with secondaries being created in both the atmosphere and the Martian regolith. Fully characterizing and understanding the surface radiation environment is fundamental to quantitatively assessing the habitability of Mars, and is an essential precursor measurement for future manned Mars missions. An extensive database to be used for calibration has been obtained for a wide range of energetic charged particle beams at the NASA Space Radiation Laboratory (NSRL) and the Heavy Ion Medical Accelerator in Chiba (HIMAC). Neutron calibration data at 5, 15, and 19 MeV were obtained at the Physikalisch-Technische Bundesanstalt. This talk will discuss the highlights of the RAD calibration campaigns and talk about what we have learned from these campaigns with respect to operating RAD on the Martian surface. We will also discuss other mission applications for RAD where dosimetry in mixed fields of energetic charged and neutral particles is needed.

  18. Radiation hardness of the storage phosphor europium doped potassium chloride for radiation therapy dosimetry

    SciTech Connect

    Driewer, Joseph P.; Chen, Haijian; Osvet, Andres; Low, Daniel A.; Li, H. Harold

    2011-08-15

    Purpose: An important property of a reusable dosimeter is its radiation hardness, that is, its ability to retain its dosimetric merits after irradiation. The radiation hardness of europium doped potassium chloride (KCl:Eu{sup 2+}), a storage phosphor material recently proposed for radiation therapy dosimetry, is examined in this study. Methods: Pellet-style KCl:Eu{sup 2+} dosimeters, 6 mm in diameter, and 1 mm thick, were fabricated in-house for this study. The pellets were exposed by a 6 MV photon beam or in a high dose rate {sup 137}Cs irradiator. Macroscopic properties, such as radiation sensitivity, dose response linearity, and signal stability, were studied with a laboratory photostimulated luminescence (PSL) readout system. Since phosphor performance is related to the state of the storage centers and the activator, Eu{sup 2+}, in the host lattice, spectroscopic and temporal measurements were carried out in order to explore radiation-induced changes at the microscopic level. Results: KCl:Eu{sup 2+} dosimeters retained approximately 90% of their initial signal strength after a 5000 Gy dose history. Dose response was initially supralinear over the dose range of 100-700 cGy but became linear after 60 Gy. Linearity did not change significantly in the 0-5000 Gy dose history spanned in this study. Annealing high dose history chips resulted in a return of supralinearity and a recovery of sensitivity. There were no significant changes in the PSL stimulation spectra, PSL emission spectra, photoluminescence spectra, or luminescence lifetime, indicating that the PSL signal process remains intact after irradiation but at a reduced efficiency due to reparable radiation-induced perturbations in the crystal lattice. Conclusions: Systematic studies of KCl:Eu{sup 2+} material are important for understanding how the material can be optimized for radiation therapy dosimetry purposes. The data presented here indicate that KCl:Eu{sup 2+} exhibits strong radiation hardness and

  19. REAC/TS Radiation Accident Registry: An Overview

    SciTech Connect

    Doran M. Christensen, DO, REAC /TS Associate Director and Staff Physician Becky Murdock, REAC/TS Registry and Health Physics Technician

    2012-12-12

    Over the past four years, REAC/TS has presented a number of case reports from its Radiation Accident Registry. Victims of radiological or nuclear incidents must meet certain dose criteria for an incident to be categorized as an “accident” and be included in the registry. Although the greatest numbers of “accidents” in the United States that have been entered into the registry involve radiation devices, the greater percentage of serious accidents have involved sealed sources of one kind or another. But if one looks at the kinds of accident scenarios that have resulted in extreme consequence, i.e., death, the greater share of deaths has occurred in medical settings.

  20. International Standardization of the Clinical Dosimetry of Beta Radiation Brachytherapy Sources: Progress of an ISO Standard

    NASA Astrophysics Data System (ADS)

    Soares, Christopher

    2006-03-01

    In 2004 a new work item proposal (NWIP) was accepted by the International Organization for Standardization (ISO) Technical Committee 85 (TC85 -- Nuclear Energy), Subcommittee 2 (Radiation Protection) for the development of a standard for the clinical dosimetry of beta radiation sources used for brachytherapy. To develop this standard, a new Working Group (WG 22 - Ionizing Radiation Dosimetry and Protocols in Medical Applications) was formed. The standard is based on the work of an ad-hoc working group initiated by the Dosimetry task group of the Deutsches Insitiut für Normung (DIN). Initially the work was geared mainly towards the needs of intravascular brachytherapy, but with the decline of this application, more focus has been placed on the challenges of accurate dosimetry for the concave eye plaques used to treat ocular melanoma. Guidance is given for dosimetry formalisms, reference data to be used, calibrations, measurement methods, modeling, uncertainty determinations, treatment planning and reporting, and clinical quality control. The document is currently undergoing review by the ISO member bodies for acceptance as a Committee Draft (CD) with publication of the final standard expected by 2007. There are opportunities for other ISO standards for medical dosimetry within the framework of WG22.

  1. Technical Performance of the Luxel Al2O3:C Optically Stimulated Luminescence Dosemeter Element at Radiation Oncology and Nuclear Accident Dose Levels

    SciTech Connect

    Miller, Steven D.; Murphy, Mark K.

    2006-12-12

    The dose ranges typical for radiation oncology and nuclear accident dosimetry are on the order of 2?70 Gy and 0.1?5 Gy, respectively. In terms of solid-state passive dosimetry; thermoluminescent (TL) materials historically have been used extensively for these two applications, with silver-halide, leuco-dye, and BaFBr:Eu-based films being used on a more limited basis than TL for radiation oncology. This present work provides results on the performance of a film based on an aluminum oxide, Al2O3:C, for these dosimetry applications, using the optically-stimulated luminescence (OSL) readout method. There have been few investigations of Al2O3:C performance at radiation oncology and nuclear accident dose levels, and these have included minimal dosimetric and environmental effects information. Based on investigations already published, the authors of this present study determined that overall improvements over film and TLDs for this Al2O3:C OSL technology at radiation oncology and nuclear accident dose levels may include (1) a more tissue-equivalent response to photons compared to X-ray film, (2) higher sensitivity, (3) ability to reread dosemeters, and (4) diagnostic capability using small-area imaging. The results of the present investigation indicate that additional favorable performance characteristics for the Al2O3:C dosemeter are a wide dynamic range(0.001 to 100 Gy), a response insensitive to temperature and moisture over a wide range, negligible dose rate dependence, and minimal change in post-irradiation response. As a radiation detection medium, this OSL phosphor offers an assortment of dosimetry properties that will permit it to compete with current radiation detection technologies such as silver-halide, leuco-dye, and photostimulable-phosphor based films, as well as TLDs.

  2. Environmental Aftermath of the Radiation Accident at Tomsk-7

    NASA Astrophysics Data System (ADS)

    Porfiriev, Boris N.; Porfiriev, Boris N.

    1996-01-01

    An analysis is presented of the environmental effects of the most serious radiation accident recorded after Chernobyl, which occurred in the formerly secret town of Tomsk-7 in Siberia, Russia, on 6, April 1993. Fortunately, it appears not to have become a major industrial crisis or disaster. The causes of the accident are described. It is argued that a mixture of both objective and subjective prerequisites, including specific human, organizational, and technological factors, were responsible for the explosion or directly facilitated it. The Tomsk-7 accident’s ecological, medical, social, and psychological consequences are discussed.

  3. Sugar as an emergency populace dosimeter for radiation accidents

    SciTech Connect

    Nakajima, T.

    1988-12-01

    Ordinary sugar can be used as an emergency dosimeter for any person exposed to a nuclear or radiation accident. The number of free radicals in sugar created by radiation does not decrease at room temperature for two months after irradiation and is not changed by thermal treatment for about 18 h at even 55 degrees C. A 600 mg granulated sugar sample can detect about 0.05 Gy (5 rad) as the minimum detectable absorbed dose using electron spin resonance equipment. If sugar is present at the time of a radiation or nuclear accident, the absorbed dose can be evaluated from the sugar and will be useful for both the medical treatment and health effects of the exposed persons.

  4. NEUTRON AND NON-NEUTRON NUCLEAR DATA FOR RADIATION DOSIMETRY

    SciTech Connect

    HOLDEN,N.E.

    1999-09-10

    NEUTRON NUCLEAR DATA THAT IS USED IN REACTOR DOSIMETRY INCLUDE THERMAL NEUTRON CROSS SECTIONS AND NEUTRON RESONANCE INTEGRALS, FISSION SPECTRUM AVERAGED CROSS SECTIONS FOR REACTIONS ON A TARGET NUCLEUS. NON-NEUTRON NUCLEAR DATA USED IN REACTOR DOSIMETRY INCLUDE ISOTOPIC COMPOSITIONS OF TARGET NUCLIDES AND RADIOACTIVE HALF-LIVES, GAMMA-RAY ENERGIES AND INTENSITIES OF REACTION PRODUCT NUCLIDES. ALL OF THESE DATA ARE PERIODICALLY EVALUATED AND RECOMMENDED VALUES ARE PROVIDED IN THE HANDBOOK OF CHEMISTRY AND PHYSICS. THE LATEST RECOMMENDED VALUES ARE DISCUSSED AND THEY ARE CONTRASTED WITH SOME EARLIER NUCLEAR DATA, WHICH WAS PROVIDED WITH NEUTRON DETECTOR FOILS.

  5. Radiation accident at Mayapuri scrap market, Delhi, 2010.

    PubMed

    Dey, A B; Mohanan, Sandeep; Damodaran, Deepak; Soneja, Manish; Jain, Neetu; Mohan, Anant; Vikram, Naval Kishore; Sood, Rita

    2012-10-01

    This article reports the accidental public radiation exposure in a scrap market in Delhi, India, on March 2010. The source, a gamma unit containing Cobalt-60 pencils, was improperly disposed of by a research institution in violation of national regulations for radiation protection and safety of radioactive sources. The unit was sold off to unsuspecting scrap dealers who dismantled the equipment. This event subsequently caused the most severe radiation accident reported in India to date, resulting in seven radiation injuries and one death. The clinical course of five of the patients treated at the All India Institute of Medical Sciences hospital, New Delhi, is summarised in this report. All five patients suffered from the haematological form of the acute radiation syndrome and local cutaneous radiation injury as well. While four patients exposed to doses between 0.6 and 2.8 Gy survived with intensive or supportive treatment, the patient with the highest exposure of 3.1 Gy died due to acute respiratory distress syndrome and multi-organ failure on Day 16 after hospitalisation. The incident highlights the current gaps in the knowledge, infrastructure and legislation in handling radioactive materials. Medical institutions need to formulate individualised triage and management guidelines to immediately respond to future public radiological accidents.

  6. Fourth conference on radiation protection and dosimetry: Proceedings, program, and abstracts

    SciTech Connect

    Casson, W.H.; Thein, C.M.; Bogard, J.S.

    1994-10-01

    This Conference is the fourth in a series of conferences organized by staff members of Oak Ridge National Laboratory in an effort to improve communication in the field of radiation protection and dosimetry. Scientists, regulators, managers, professionals, technologists, and vendors from the United States and countries around the world have taken advantage of this opportunity to meet with their contemporaries and peers in order to exchange information and ideas. The program includes over 100 papers in 9 sessions, plus an additional session for works in progress. Papers are presented in external dosimetry, internal dosimetry, radiation protection programs and assessments, developments in instrumentation and materials, environmental and medical applications, and on topics related to standards, accreditation, and calibration. Individual papers are indexed separately on EDB.

  7. Novel Multicompartment 3-Dimensional Radiochromic Radiation Dosimeters for Nanoparticle-Enhanced Radiation Therapy Dosimetry

    SciTech Connect

    Alqathami, Mamdooh; Blencowe, Anton; Yeo, Un Jin; Doran, Simon J.; Qiao, Greg; Geso, Moshi

    2012-11-15

    Purpose: Gold nanoparticles (AuNps), because of their high atomic number (Z), have been demonstrated to absorb low-energy X-rays preferentially, compared with tissue, and may be used to achieve localized radiation dose enhancement in tumors. The purpose of this study is to introduce the first example of a novel multicompartment radiochromic radiation dosimeter and to demonstrate its applicability for 3-dimensional (3D) dosimetry of nanoparticle-enhanced radiation therapy. Methods and Materials: A novel multicompartment phantom radiochromic dosimeter was developed. It was designed and formulated to mimic a tumor loaded with AuNps (50 nm in diameter) at a concentration of 0.5 mM, surrounded by normal tissues. The novel dosimeter is referred to as the Sensitivity Modulated Advanced Radiation Therapy (SMART) dosimeter. The dosimeters were irradiated with 100-kV and 6-MV X-ray energies. Dose enhancement produced from the interaction of X-rays with AuNps was calculated using spectrophotometric and cone-beam optical computed tomography scanning by quantitatively comparing the change in optical density and 3D datasets of the dosimetric measurements between the tissue-equivalent (TE) and TE/AuNps compartments. The interbatch and intrabatch variability and the postresponse stability of the dosimeters with AuNps were also assessed. Results: Radiation dose enhancement factors of 1.77 and 1.11 were obtained using 100-kV and 6-MV X-ray energies, respectively. The results of this study are in good agreement with previous observations; however, for the first time we provide direct experimental confirmation and 3D visualization of the radiosensitization effect of AuNps. The dosimeters with AuNps showed small (<3.5%) interbatch variability and negligible (<0.5%) intrabatch variability. Conclusions: The SMART dosimeter yields experimental insights concerning the spatial distributions and elevated dose in nanoparticle-enhanced radiation therapy, which cannot be performed using any of

  8. Fostering a culture of interprofessional education for radiation therapy and medical dosimetry students

    SciTech Connect

    Lavender, Charlotte Miller, Seth; Church, Jessica; Chen, Ronald C.; Muresan, Petronella A.; Adams, Robert D.

    2014-04-01

    A less-studied aspect of radiation therapy and medical dosimetry education is experiential learning through attendance at interprofessional conferences. University of North Carolina radiation therapy and medical dosimetry students regularly attended morning conferences and daily pretreatment peer review, including approximately 145 hours of direct interaction with medical attending physicians and residents, medical physicists, and other faculty. We herein assessed the effect of their participation in these interprofessional conferences on knowledge and communication. The students who graduated from our radiation therapy and medical dosimetry programs who were exposed to the interprofessional education initiative were compared with those who graduated in the previous years. The groups were compared with regard to their knowledge (as assessed by grades on end-of-training examinations) and team communication (assessed via survey). The results for the 2 groups were compared via exact tests. There was a trend for the examination scores for the 2012 cohort to be higher than for the 2007 to 2011 groups. Survey results suggested that students who attended the interprofessional education sessions were more comfortable speaking with attending physicians, residents, physicists, and faculty compared with earlier students who did not attend these educational sessions. Interprofessional education, particularly vertical integration, appears to provide an enhanced educational experience both in regard to knowledge (per the examination scores) and in building a sense of communication (via the survey results). Integration of interprofessional education into radiation therapy and medical dosimetry educational programs may represent an opportunity to enrich the learning experience in multiple ways and merits further study.

  9. Dosimetry of Atomic Bomb Radiation in Hiroshima by Thermoluminescence of Roof Tiles.

    PubMed

    Higashimura, T; Ichikawa, Y; Sidei, T

    1963-03-29

    Thermoluminescence dosimetry is a powerful tool for obtaining the distribution of gamma dose, heretofore unknown, from the atomic bombs dropped on Hiroshima and Nagasaki. Roof tiles irradiated by the bombs show intense thermoluminescence, and the radiation dose for samples irradiated below 100 r by the bomb can be measured by this method.

  10. Photon dosimetry using plastic scintillators in pulsed radiation fields

    SciTech Connect

    David L. Chichester; Brandon W. Blackburn; James T. Johnson; Scott W. Watson

    2007-04-01

    Simulations and experiments have been carried out to explore using a plastic scintillator as a dosimetry probe in the vicinity of a pulsed bremsstrahlung source in the range 4 to 20 MeV. Taking advantage of the tissue-equivalent properties of this detector in conjunction with the use of a fast digital signal processor near real-time dosimetry was shown to be possible. The importance of accounting for a broad energy electron beam in bremsstrahlung production, and photon scattering and build-up, in correctly interpreting dosimetry results at long stand-off distances is highlighted by comparing real world experiments with ideal geometry simulations. Close agreement was found between absorbed energy calculations based upon spectroscopic techniques and calculations based upon signal integration, showing a ratio between 10 MeV absorbed dose to 12 MeV absorbed dose of 0.66 at a distance of 91.4 m from the accelerator. This is compared with an idealized model simulation with a monoenergetic electron beam and without scattering, where the ratio was 0.46.

  11. Micro-Fabricated Solid-State Radiation Detectors for Active Personal Dosimetry

    NASA Technical Reports Server (NTRS)

    Wrbanek, John D.; Wrbanek, Susan Y.; Fralick, Gustave C.; Chen, Liang-Yu

    2007-01-01

    Active radiation dosimetry is important to human health and equipment functionality for space applications outside the protective environment of a space station or vehicle. This is especially true for long duration missions to the moon, where the lack of a magnetic field offers no protection from space radiation to those on extravehicular activities. In order to improve functionality, durability and reliability of radiation dosimeters for future NASA lunar missions, single crystal silicon carbide devices and scintillating fiber detectors are currently being investigated for applications in advanced extravehicular systems. For many years, NASA Glenn Research Center has led significant efforts in silicon carbide semiconductor technology research and instrumentation research for sensor applications under extreme conditions. This report summarizes the technical progress and accomplishments toward characterization of radiation-sensing components for the recommendation of their fitness for advanced dosimetry development.

  12. RADIATION DOSIMETRY AT THE BNL HIGH FLUX BEAM REACTOR AND MEDICAL RESEARCH REACTOR.

    SciTech Connect

    HOLDEN,N.E.

    1999-09-10

    RADIATION DOSIMETRY MEASUREMENTS HAVE BEEN PERFORMED OVER A PERIOD OF MANY YEARS AT THE HIGH FLUX BEAM REACTOR (HFBR) AND THE MEDICAL RESEARCH REACTOR (BMRR) AT BROOKHAVEN NATIONAL LABORATORY TO PROVIDE INFORMATION ON THE ENERGY DISTRIBUTION OF THE NEUTRON FLUX, NEUTRON DOSE RATES, GAMMA-RAY FLUXES AND GAMMA-RAY DOSE RATES. THE MCNP PARTICLE TRANSPORT CODE PROVIDED MONTE CARLO RESULTS TO COMPARE WITH VARIOUS DOSIMETRY MEASUREMENTS PERFORMED AT THE EXPERIMENTAL PORTS, AT THE TREATMENT ROOMS AND IN THE THIMBLES AT BOTH HFBR AND BMRR.

  13. Radiation signatures in childhood thyroid cancers after the Chernobyl accident: Possible roles of radiation in carcinogenesis

    PubMed Central

    Suzuki, Keiji; Mitsutake, Norisato; Saenko, Vladimir; Yamashita, Shunichi

    2015-01-01

    After the Tokyo Electric Power Company Fukushima Daiichi nuclear power plant accident, cancer risk from low-dose radiation exposure has been deeply concerning. The linear no-threshold model is applied for the purpose of radiation protection, but it is a model based on the concept that ionizing radiation induces stochastic oncogenic alterations in the target cells. As the elucidation of the mechanism of radiation-induced carcinogenesis is indispensable to justify the concept, studies aimed at the determination of molecular changes associated with thyroid cancers among children who suffered effects from the Chernobyl nuclear accident will be overviewed. We intend to discuss whether any radiation signatures are associated with radiation-induced childhood thyroid cancers. PMID:25483826

  14. Radiation signatures in childhood thyroid cancers after the Chernobyl accident: possible roles of radiation in carcinogenesis.

    PubMed

    Suzuki, Keiji; Mitsutake, Norisato; Saenko, Vladimir; Yamashita, Shunichi

    2015-02-01

    After the Tokyo Electric Power Company Fukushima Daiichi nuclear power plant accident, cancer risk from low-dose radiation exposure has been deeply concerning. The linear no-threshold model is applied for the purpose of radiation protection, but it is a model based on the concept that ionizing radiation induces stochastic oncogenic alterations in the target cells. As the elucidation of the mechanism of radiation-induced carcinogenesis is indispensable to justify the concept, studies aimed at the determination of molecular changes associated with thyroid cancers among children who suffered effects from the Chernobyl nuclear accident will be overviewed. We intend to discuss whether any radiation signatures are associated with radiation-induced childhood thyroid cancers. PMID:25483826

  15. Radiation signatures in childhood thyroid cancers after the Chernobyl accident: possible roles of radiation in carcinogenesis.

    PubMed

    Suzuki, Keiji; Mitsutake, Norisato; Saenko, Vladimir; Yamashita, Shunichi

    2015-02-01

    After the Tokyo Electric Power Company Fukushima Daiichi nuclear power plant accident, cancer risk from low-dose radiation exposure has been deeply concerning. The linear no-threshold model is applied for the purpose of radiation protection, but it is a model based on the concept that ionizing radiation induces stochastic oncogenic alterations in the target cells. As the elucidation of the mechanism of radiation-induced carcinogenesis is indispensable to justify the concept, studies aimed at the determination of molecular changes associated with thyroid cancers among children who suffered effects from the Chernobyl nuclear accident will be overviewed. We intend to discuss whether any radiation signatures are associated with radiation-induced childhood thyroid cancers.

  16. PREFACE: 7th International Conference on 3D Radiation Dosimetry (IC3DDose)

    NASA Astrophysics Data System (ADS)

    Thwaites, David; Baldock, Clive

    2013-06-01

    IC3DDose 2013, the 7th International Conference on 3D Radiation Dosimetry held in Sydney, Australia from 4-8 November 2012, grew out of the DosGel series, which began as DosGel99, the 1st International Workshop on Radiation Therapy Gel Dosimetry in Lexington, Kentucky. Since 1999 subsequent DoSGel conferences were held in Brisbane, Australia (2001), Ghent, Belgium (2004), Sherbrooke, Canada (2006) and Crete, Greece (2008). In 2010 the conference was held on Hilton Head Island, South Carolina and underwent a name-change to IC3DDose. The aim of the first workshop was to bring together individuals, both researchers and users, with an interest in 3D radiation dosimetry techniques, with a mix of presentations from basic science to clinical applications, which has remained an objective for all of the meetings. One rationale of DosGel99 was stated as supporting the increasing clinical implementation of gel dosimetry, as the technique appeared, at that time, to be leaving the laboratories of gel dosimetry enthusiasts and entering clinical practice. Clearly by labelling the first workshop as the 1st, there was a vision of a continuing series, which has been fulfilled. On the other hand, the expectation of widespread clinical use of gel dosimetry has perhaps not been what was hoped for and anticipated. Nevertheless the rapidly increasing demand for advanced high-precision 3D radiotherapy technology and techniques has continued apace. The need for practical and accurate 3D dosimetry methods for development and quality assurance has only increased. By the 6th meeting, held in South Carolina in 2010, the Conference Scientific Committee recognised the wider developments in 3D systems and methods and decided to widen the scope, whilst keeping the same span from basic science to applications. This was signalled by a change of name from 'Dosgel' to 'IC3DDose', a name that has continued to this latest conference. The conference objectives were: to enhance the quality and accuracy of

  17. Optically stimulated luminescence dosimetry performance of natural Brazilian topaz exposed to beta radiation.

    PubMed

    Bernal, R; Souza, D N; Valerio, M E G; Cruz-Vázquez, C; Barboza-Flores, M

    2006-01-01

    Optically stimulated luminescence (OSL) has become the technique of choice in many areas of dosimetry. Natural materials like topaz are available in large quantities in Brazil and other countries. They have been studied to investigate the possibility of use its thermoluminescence (TL) properties for dosimetric applications. In this work, we investigate the possibility of utilising the OSL properties of natural Brazilian topaz in dosimetry. Bulk topaz samples were exposed to doses up to 100 Gy of beta radiation and the integrated OSL as a function of the dose showed linear behaviour. The fading occurs in the first 20 min after irradiation but it is <6% of the integrated OSL measured shortly after exposure. We conclude that natural colourless topaz is a very suitable phosphor for OSL dosimetry.

  18. Protocol for emergency EPR dosimetry in fingernails

    Technology Transfer Automated Retrieval System (TEKTRAN)

    There is an increased need for after-the fact dosimetry because of the high risk of radiation exposures due to terrorism or accidents. In case of such an event, a method is needed to make measurements of dose in a large number of individuals rapidly and with sufficient accuracy to facilitate effect...

  19. Biology versus engineering: the TMI accident as a case study in problems of dosimetry.

    PubMed

    Aamodt, N O

    2000-01-01

    Official investigations concluded that no environmental damage was caused by the 1979 accident at the Three Mile Island nuclear generation plant, Unit 2 (TMI). Years later, highly-exposed populations were discovered through investigation of anecdotal information. Absorbed doses in the order of 1 Gy were confirmed by cytogenic and immune status tests. PMID:11130947

  20. Dosimetry for quantitative analysis of low dose ionizing radiation effects on humans in radiation therapy patients

    SciTech Connect

    Lehmann, J; Stern, R L; Daly, T P; Schwieter, C W; Jones, G E; Arnold, M L; Hartmann-Siantar, C L; Goldberg, Z

    2004-04-20

    We have successfully developed a practical approach to predicting the location of skin surface dose at potential biopsy sites that receive 1 cGy and 10 cGy, respectively, in support of in vivo biologic dosimetry in humans. This represents a significant technical challenge as the sites lie on the patient surface out side the radiation fields. The PEREGRINE Monte Carlo simulation system was used to model radiation dose delivery and TLDs were used for validation on a phantom and confirmation during patient treatment. In the developmental studies the Monte Carlo simulations consistently underestimated the dose at the biopsy site by approximately 15% for a realistic treatment configuration, most likely due to lack of detail in the simulation of the linear accelerator outside the main beam line. Using a single, thickness-independent correction factor for the clinical calculations, the average of 36 measurements for the predicted 1 cGy point was 0.985 cGy (standard deviation: 0.110 cGy) despite patient breathing motion and other real world challenges. Since the 10 cGy point is situated in the region of high dose gradient at the edge of the field, patient motion had a greater effect and the six measured points averaged 5.90 cGy (standard deviation: 1.01 cGy), a difference that is equivalent to approximately a 6 mm shift on the patient's surface.

  1. PREFACE: 8th International Conference on 3D Radiation Dosimetry (IC3DDose)

    NASA Astrophysics Data System (ADS)

    Olsson, Lars E.; Bäck, S.; Ceberg, Sofie

    2015-01-01

    IC3DDose 2014, the 8th International Conference on 3D Radiation Dosimetry was held in Ystad, Sweden, from 4-7 September 2014. This grew out of the DosGel series, which began as DosGel99, the 1st International Workshop on Radiation Therapy Gel Dosimetry in Lexington, Kentucky. Since 1999 subsequent DoSGel conferences were held in Brisbane, Australia (2001), Ghent, Belgium (2004), Sherbrooke, Canada (2006) and Crete, Greece (2008). In 2010 the conference was held on Hilton Head Island, South Carolina and underwent a name-change to IC3DDose. The 7th and last meeting was held in Sydney, Australia from 4-8 November 2012. It is worth remembering that the conference series started at the very beginning of the intensity modulated radiotherapy era and that the dosimeters being developed then were, to some extent, ahead of the clinical need of radiotherapy. However, since then the technical developments in radiation therapy have been dramatic, with dynamic treatments, including tracking, gating and volumetric modulated arc therapy, widely introduced in the clinic with the need for 3D dosimetry thus endless. This was also reflected by the contributions at the meeting in Ystad. Accordingly the scope of the meeting has also broadened to IC3DDOSE - I See Three-Dimensional Dose. A multitude of dosimetry techniques and radiation detectors are now represented, all with the common denominator: three-dimensional or 3D. Additionally, quality assurance (QA) procedures and other aspects of clinical dosimetry are represented. The implementation of new dosimetric techniques in radiotherapy is a process that needs every kind of caution, carefulness and thorough validation. Therefore, the clinical needs, reformulated as the aims for IC3DDOSE - I See Three-Dimensional Dose, are: • Enhance the quality and accuracy of radiation therapy treatments through improved clinical dosimetry. • Investigate and understand the dosimetric challenges of modern radiation treatment techniques. • Provide

  2. Cerium-activated sol-gel silica glasses for radiation dosimetry in harsh environment

    NASA Astrophysics Data System (ADS)

    El Hamzaoui, Hicham; Capoen, Bruno; Helou, Nissrine Al; Bouwmans, Géraud; Ouerdane, Youcef; Boukenter, Aziz; Girard, Sylvain; Marcandella, Claude; Duhamel, Olivier; Chadeyron, Geneviève; Mahiou, Rachid; Bouazaoui, Mohamed

    2016-04-01

    Cerium-doped silica glass has been prepared for ionizing radiation dosimetry applications, using the sol-gel route and densification under different atmospheres. In comparison with the glass densified under air atmosphere, the one obtained after sintering the xerogel under helium gas presents improved optical properties, with an enhancement of the photoluminescence quantum yield up to 33%, which is attributed to a higher Ce3+ ions concentration. Such a glassy rod has been jacketed in a quartz tube and then drawn at high temperature to a cane, which has been used as active material in a fibered remote x-ray radiation dosimeter. The sample exhibited a reversible linear radioluminescence intensity response versus the dose rate up to 30 Gy s-1. These results confirm the potentialities of this material for in vivo or high rate dose remote dosimetry measurements.

  3. BREN Tower: A Monument to the Material Culture of Radiation Dosimetry Research

    SciTech Connect

    Susan Edwards

    2008-05-30

    With a height of more than 1,500 feet, the BREN (Bare Reactor Experiment, Nevada) Tower dominates the surrounding desert landscape of the Nevada Test Site. Associated with the nuclear research and atmospheric testing programs carried out during the 1950s and 1960s, the tower was a vital component in a series of experiments aimed at characterizing radiation fields from nuclear detonations. Research programs conducted at the tower provided the data for the baseline dosimetry studies crucial to determining the radiation dose rates received by the atomic bomb survivors of Hiroshima and Nagasaki, Japan. Today, BREN Tower stands as a monument to early dosimetry research and one of the legacies of the Cold War.

  4. Small Radiation Beam Dosimetry for Radiosurgery of Trigeminal Neuralgia: One Case Analysis

    SciTech Connect

    Garcia-Garduno, O. A.; Larraga-Gutierrez, J. M.; Rodriguez-Villafuerte, M.; Martinez-Davalos, A.; Moreno-Jimenez, S.; Suarez-Campos, J. J.; Celis, M. A.

    2008-08-11

    The use of small radiation beams for trigeminal neuralgia (TN) treatment requires high precision and accuracy in dose distribution calculations and delivery. Special attention must be kept on the type of detector to be used. In this work, the use of GafChromic EBT registered radiochromic and X-OMAT V2 radiographic films for small radiation beam characterization is reported. The dosimetric information provided by the films (total output factors, tissue maximum ratios and off axis ratios) is compared against measurements with a shielded solid state (diode) reference detector. The film dosimetry was used for dose distribution calculations for the treatment of trigeminal neuralgia radiosurgery. Comparison of the isodose curves shows that the dosimetry produced with the X-OMAT radiographic film overestimates the dose distributions in the penumbra region.

  5. Small Radiation Beam Dosimetry for Radiosurgery of Trigeminal Neuralgia: One Case Analysis

    NASA Astrophysics Data System (ADS)

    García-Garduño, O. A.; Lárraga-Gutiérrez, J. M.; Rodríguez-Villafuerte, M.; Martínez-Dávalos, A.; Moreno-Jiménez, S.; Suárez-Campos, J. J.; Celis, M. A.

    2008-08-01

    The use of small radiation beams for trigeminal neuralgia (TN) treatment requires high precision and accuracy in dose distribution calculations and delivery. Special attention must be kept on the type of detector to be used. In this work, the use of GafChromic EBT® radiochromic and X-OMAT V2 radiographic films for small radiation beam characterization is reported. The dosimetric information provided by the films (total output factors, tissue maximum ratios and off axis ratios) is compared against measurements with a shielded solid state (diode) reference detector. The film dosimetry was used for dose distribution calculations for the treatment of trigeminal neuralgia radiosurgery. Comparison of the isodose curves shows that the dosimetry produced with the X-OMAT radiographic film overestimates the dose distributions in the penumbra region.

  6. ASSESSMENT OF UNCERTAINTY IN THE RADIATION DOSES FOR THE TECHA RIVER DOSIMETRY SYSTEM

    SciTech Connect

    Napier, Bruce A.; Degteva, M. O.; Anspaugh, L. R.; Shagina, N. B.

    2009-10-23

    In order to provide more accurate and precise estimates of individual dose (and thus more precise estimates of radiation risk) for the members of the ETRC, a new dosimetric calculation system, the Techa River Dosimetry System-2009 (TRDS-2009) has been prepared. The deterministic version of the improved dosimetry system TRDS-2009D was basically completed in April 2009. Recent developments in evaluation of dose-response models in light of uncertain dose have highlighted the importance of different types of uncertainties in the development of individual dose estimates. These include uncertain parameters that may be either shared or unshared within the dosimetric cohort, and also the nature of the type of uncertainty as aleatory or epistemic and either classical or Berkson. This report identifies the nature of the various input parameters and calculational methods incorporated in the Techa River Dosimetry System (based on the TRDS-2009D implementation), with the intention of preparing a stochastic version to estimate the uncertainties in the dose estimates. This report reviews the equations, databases, and input parameters, and then identifies the author’s interpretations of their general nature. It presents the approach selected so that the stochastic, Monte-Carlo, implementation of the dosimetry System - TRDS-2009MC - will provide useful information regarding the uncertainties of the doses.

  7. GENII: The Hanford Environmental Radiation Dosimetry Software System: Volume 1, Conceptual representation

    SciTech Connect

    Napier, B.A.; Peloquin, R.A.; Strenge, D.L.; Ramsdell, J.V.

    1988-12-01

    The Hanford Environmental Dosimetry Upgrade Project was undertaken to incorporate the internal dosimetry models recommended by the International Commission on Radiological Protection (ICRP) in updated versions of the environmental pathway analysis models used at Hanford. The resulting second generation of Hanford environmental dosimetry computer codes is compiled in the Hanford Environmental Dosimetry System (Generation II, or GENII). The purpose of this coupled system of computer codes is to analyze environmental contamination resulting from acute or chronic releases to, or initial contamination of, air, water, or soil. This is accomplished by calculating radiation doses to individuals or populations. GENII is described in three volumes of documentation. The first volume describes the theoretical considerations of the system. The second volume is a Users' Manual, providing code structure, users' instructions, required system configurations, and QA-related topics. The third volume is a Code Maintenance Manual for the user who requires knowledge of code detail. It includes code logic diagrams, global dictionary, worksheets, example hand calculations, and listings of the code and its associated data libraries. 72 refs., 15 figs., 34 tabs.

  8. Radiation-induced late effects in two affected individuals of the Lilo radiation accident.

    PubMed

    Scherthan, Harry; Abend, Michael; Müller, Kerstin; Beinke, Christina; Braselmann, Herbert; Zitzelsberger, Horst; Köhn, Frank M; Pillekamp, Hans; Schiener, Ralf; Das, Oliver; Peter, Ralf U; Herzog, Gerhard; Tzschach, Andreas; Dörr, Harald D; Fliedner, Theodor M; Meineke, Viktor

    2007-05-01

    Radiation exposure leads to a risk for long-term deterministic and stochastic late effects. Two individuals exposed to protracted photon radiation in the radiological accident at the Lilo Military site in Georgia in 1997 received follow-up treatment and resection of several chronic radiation ulcers in the Bundeswehr Hospital Ulm, Germany, in 2003. Multi-parameter analysis revealed that spermatogenetic arrest and serum hormone levels in both patients had recovered compared to the status in 1997. However, we observed a persistence of altered T-cell ratios, increased ICAM1 and beta1-integrin expression, and aberrant bone marrow cells and lymphocytes with significantly increased translocations 6 years after the accident. This investigation thus identified altered end points still detectable years after the accident that suggest persistent genomic damage as well as epigenetic effects in these individuals, which may be associated with an elevated risk for the development of further late effects. Our observations further suggest the development of a chronic radiation syndrome and indicate follow-up parameters in radiation victims.

  9. The Application of FLUKA to Dosimetry and Radiation Therapy

    NASA Technical Reports Server (NTRS)

    Wilson, Thomas L.; Andersen, Victor; Pinsky, Lawrence; Ferrari, Alfredo; Battistoni, Giusenni

    2005-01-01

    Monte Carlo transport codes like FLUKA are useful for many purposes, and one of those is the simulation of the effects of radiation traversing the human body. In particular, radiation has been used in cancer therapy for a long time, and recently this has been extended to include heavy ion particle beams. The advent of this particular type of therapy has led to the need for increased capabilities in the transport codes used to simulate the detailed nature of the treatment doses to the Y O U S tissues that are encountered. This capability is also of interest to NASA because of the nature of the radiation environment in space.[l] While in space, the crew members bodies are continually being traversed by virtually all forms of radiation. In assessing the risk that this exposure causes, heavy ions are of primary importance. These arise both from the primary external space radiation itself, as well as fragments that result from interactions during the traversal of that radiation through any intervening material including intervening body tissue itself. Thus the capability to characterize the details of the radiation field accurately within a human body subjected to such external 'beams" is of critical importance.

  10. Micrometer-resolved film dosimetry using a microscope in microbeam radiation therapy

    SciTech Connect

    Bartzsch, Stefan Oelfke, Uwe; Lott, Johanna; Welsch, Katrin; Bräuer-Krisch, Elke

    2015-07-15

    Purpose: Microbeam radiation therapy (MRT) is a still preclinical tumor therapy approach that uses arrays of a few tens of micrometer wide parallel beams separated by a few 100 μm. The production, measurement, and planning of such radiation fields are a challenge up to now. Here, the authors investigate the feasibility of radiochromic film dosimetry in combination with a microscopic readout as a tool to validate peak and valley doses in MRT, which is an important requirement for a future clinical application of the therapy. Methods: Gafchromic{sup ®} HD-810 and HD-V2 films are exposed to MRT fields at the biomedical beamline ID17 of the European Synchrotron Radiation Facility (ESRF) and are afterward scanned with a microscope. The measured dose is compared with Monte Carlo calculations. Image analysis tools and film handling protocols are developed that allow accurate and reproducible dosimetry. The performance of HD-810 and HD-V2 films is compared and a detailed analysis of the resolution, noise, and energy dependence is carried out. Measurement uncertainties are identified and analyzed. Results: The dose was measured with a resolution of 5 × 1000 μm{sup 2} and an accuracy of 5% in the peak and between 10% and 15% in the valley region. As main causes for dosimetry uncertainties, statistical noise, film inhomogeneities, and calibration errors were identified. Calibration errors strongly increase at low doses and exceeded 3% for doses below 50 and 70 Gy for HD-V2 and HD-810 films, respectively. While the grain size of both film types is approximately 2 μm, the statistical noise in HD-V2 is much higher than in HD-810 films. However, HD-810 films show a higher energy dependence at low photon energies. Conclusions: Both film types are appropriate for dosimetry in MRT and the microscope is superior to the microdensitometer used before at the ESRF with respect to resolution and reproducibility. However, a very careful analysis of the image data is required

  11. Advances in dosimetry and biological predictors of radiation-induced esophagitis

    PubMed Central

    Yu, Yang; Guan, Hui; Dong, Yuanli; Xing, Ligang; Li, Xiaolin

    2016-01-01

    Objective To summarize the research progress about the dosimetry and biological predictors of radiation-induced esophagitis. Methods We performed a systematic literature review addressing radiation esophagitis in the treatment of lung cancer published between January 2009 and May 2015 in the PubMed full-text database index systems. Results Twenty-eight eligible documents were included in the final analysis. Many clinical factors were related to the risk of radiation esophagitis, such as elder patients, concurrent chemoradiotherapy, and the intense radiotherapy regimen (hyperfractionated radiotherapy or stereotactic body radiotherapy). The parameters including Dmax, Dmean, V20, V30, V50, and V55 may be valuable in predicting the occurrence of radiation esophagitis in patients receiving concurrent chemoradiotherapy. Genetic variants in inflammation-related genes are also associated with radiation-induced toxicity. Conclusion Dosimetry and biological factors of radiation-induced esophagitis provide clinical information to decrease its occurrence and grade during radiotherapy. More prospective studies are warranted to confirm their prediction efficacy. PMID:26869804

  12. 39th Lauriston S. Taylor Lecture: Dosimetry of Internal Emitters: Contribution of Radiation Protection Bodies and Radiological Events.

    PubMed

    Eckerman, Keith F

    2016-02-01

    Since the early days of the Manhattan Engineer District, Oak Ridge National Laboratory (ORNL) has served to advance the dosimetry models used to set protection standards for radionuclides taken into the body. Throughout the years, this effort benefited significantly from ORNL staff's active participation in national and international scientific bodies. The first such interaction was in 1946 with the National Committee on Radiation Protection (NCRP), chaired by L.S. Taylor, which led to the 1949 to 1953 series of tripartite conferences of experts from Canada, the United Kingdom, and the United States. These conferences addressed the need for standardization of dosimetry models and led to the establishment of an anatomic and physiologic model called "Standard Man," a precursor of the reference worker defined in Publication 23 of the International Commission on Radiological Protection (ICRP). Standard Man was used in setting the maximum permissible concentrations in air and water published in NBS Handbook 52 and subsequent reports by NCRP and ICRP. K.Z. Morgan, then director of the Health Physics Division at ORNL, participated in the tripartite conferences and subsequently established ORNL as a modeling and computational resource for development of radiation protection standards. ORNL's role expanded with participation in the work of the Medical Internal Radiation Dose (MIRD) Committee of the Society of Nuclear Medicine. Results of interactions with the MIRD Committee are evident in the radiation protection guidance for internal emitters in ICRP Publication 30. The annual limit on intake and derived air concentration values tabulated in Publication 30 were computed by an ORNL-based task group of ICRP Committee 2. A few years after the appearance of Publication 30, the Chernobyl nuclear reactor accident made clear the need to develop standard dosimetry models for pre-adult ages as members of the public. In the late 1980s, ICRP began an effort to extend its reference

  13. 39th Lauriston S. Taylor Lecture: Dosimetry of Internal Emitters: Contribution of Radiation Protection Bodies and Radiological Events.

    PubMed

    Eckerman, Keith F

    2016-02-01

    Since the early days of the Manhattan Engineer District, Oak Ridge National Laboratory (ORNL) has served to advance the dosimetry models used to set protection standards for radionuclides taken into the body. Throughout the years, this effort benefited significantly from ORNL staff's active participation in national and international scientific bodies. The first such interaction was in 1946 with the National Committee on Radiation Protection (NCRP), chaired by L.S. Taylor, which led to the 1949 to 1953 series of tripartite conferences of experts from Canada, the United Kingdom, and the United States. These conferences addressed the need for standardization of dosimetry models and led to the establishment of an anatomic and physiologic model called "Standard Man," a precursor of the reference worker defined in Publication 23 of the International Commission on Radiological Protection (ICRP). Standard Man was used in setting the maximum permissible concentrations in air and water published in NBS Handbook 52 and subsequent reports by NCRP and ICRP. K.Z. Morgan, then director of the Health Physics Division at ORNL, participated in the tripartite conferences and subsequently established ORNL as a modeling and computational resource for development of radiation protection standards. ORNL's role expanded with participation in the work of the Medical Internal Radiation Dose (MIRD) Committee of the Society of Nuclear Medicine. Results of interactions with the MIRD Committee are evident in the radiation protection guidance for internal emitters in ICRP Publication 30. The annual limit on intake and derived air concentration values tabulated in Publication 30 were computed by an ORNL-based task group of ICRP Committee 2. A few years after the appearance of Publication 30, the Chernobyl nuclear reactor accident made clear the need to develop standard dosimetry models for pre-adult ages as members of the public. In the late 1980s, ICRP began an effort to extend its reference

  14. Computational dosimetry

    SciTech Connect

    Siebert, B.R.L.; Thomas, R.H.

    1996-01-01

    The paper presents a definition of the term ``Computational Dosimetry`` that is interpreted as the sub-discipline of computational physics which is devoted to radiation metrology. It is shown that computational dosimetry is more than a mere collection of computational methods. Computational simulations directed at basic understanding and modelling are important tools provided by computational dosimetry, while another very important application is the support that it can give to the design, optimization and analysis of experiments. However, the primary task of computational dosimetry is to reduce the variance in the determination of absorbed dose (and its related quantities), for example in the disciplines of radiological protection and radiation therapy. In this paper emphasis is given to the discussion of potential pitfalls in the applications of computational dosimetry and recommendations are given for their avoidance. The need for comparison of calculated and experimental data whenever possible is strongly stressed.

  15. [Radiation effects of the Chernobyl accident on the Hungarian population].

    PubMed

    Kanyár, Béla

    2002-05-12

    Due to the nuclear accident at Chernobyl in April 1986, the atmospheric transport spread the released radioactivity throughout the whole Europe. The initial plume moved into the north-western direction and a portion of this plum turned to west and later on to south-west. The central European countries including Hungary became affected in 29-30 April. The release during the last period (5-7 May) was directed to Romania, Bulgaria and Greece. In addition to the main trajectories of the atmospheric transport, the local meteorological conditions with winds of different directions at various altitudes, rainfalls etc. produced a very complex deposition pattern in Central Europe. The contamination of the soil surface and vegetation were strongly influenced by the wash-out of the radioactive materials from the local air. Due to the high geographical variation of the rains the surface contamination provided a similar heterogeneity among the territories of the country. The northern-west part and the region of the capital Budapest became nearly 5 times higher contaminated than the middle part of the country. Radiation doses of the population have been provided by activity concentrations in air, soil, vegetation, foods etc. and the external dose rates, mainly due to the surface contamination by the isotopes of 131I, 134Cs and 137Cs. The average effective dose contribution received by the individuals (adults) in Hungary during the 15 years following the accident has been assessed to be 0.30 mSv while the annual dose from the natural background is 2.5-3 mSv. Contribution to total dose from the internal pathway (committed effective dose) resulted about 0.10 mSv and the external radiation provided 0.19 mSv. The contributions of the external exposure from the contaminated air and inhalation are less than 5% of the total one. PMID:12063853

  16. [Radiation effects of the Chernobyl accident on the Hungarian population].

    PubMed

    Kanyár, Béla

    2002-05-12

    Due to the nuclear accident at Chernobyl in April 1986, the atmospheric transport spread the released radioactivity throughout the whole Europe. The initial plume moved into the north-western direction and a portion of this plum turned to west and later on to south-west. The central European countries including Hungary became affected in 29-30 April. The release during the last period (5-7 May) was directed to Romania, Bulgaria and Greece. In addition to the main trajectories of the atmospheric transport, the local meteorological conditions with winds of different directions at various altitudes, rainfalls etc. produced a very complex deposition pattern in Central Europe. The contamination of the soil surface and vegetation were strongly influenced by the wash-out of the radioactive materials from the local air. Due to the high geographical variation of the rains the surface contamination provided a similar heterogeneity among the territories of the country. The northern-west part and the region of the capital Budapest became nearly 5 times higher contaminated than the middle part of the country. Radiation doses of the population have been provided by activity concentrations in air, soil, vegetation, foods etc. and the external dose rates, mainly due to the surface contamination by the isotopes of 131I, 134Cs and 137Cs. The average effective dose contribution received by the individuals (adults) in Hungary during the 15 years following the accident has been assessed to be 0.30 mSv while the annual dose from the natural background is 2.5-3 mSv. Contribution to total dose from the internal pathway (committed effective dose) resulted about 0.10 mSv and the external radiation provided 0.19 mSv. The contributions of the external exposure from the contaminated air and inhalation are less than 5% of the total one.

  17. A new method of retrospective radiation dosimetry: Optically stimulated luminescence in dental enamel

    SciTech Connect

    Godfrey-Smith, D.I.; Pass, B.

    1997-05-01

    Currently, retrospective biophysical radiation dosimetry lacks a technique that is sensitive, non-invasive, and portable. This has made reliable cause and effect relationships between radiation exposure and its outcomes in humans difficult to establish. Since optical technology is amenable to miniaturization, a search for optically stimulated luminescence in dental enamel was begun. The first successful detection of time dependent optically stimulated luminescence from {gamma} irradiated enamel was accomplished. This luminescence is absent in enamel that is not irradiated or that was heated following irradiation. Thermoluminescence observations were made concurrently with the optical measurements which clarified the role of the organic component of enamel. 20 refs., 5 figs.

  18. Improved Radiation Dosimetry/Risk Estimates To Facilitate Environmental Management of Plutonium Contaminated Sites

    SciTech Connect

    Scott, Bobby, R.; Cheng, Yung-Sung; Zhou, Yue; Tokarskaya, Zoya, B.; Zhuntova, Galina, V.; Osovets, Sergey, V.; Syrchikov, Victor, A.; Pesternikova, Valentina, S.; Belyaeva, Zinaida, D.; Khokhryakov, Valentin, F; Vasilenko, Evgeny, K.; Okladnikova, Nadezhda D.

    2004-12-10

    This report is comprised of a main section and two appendices (A, B) that contain two submitted papers developed with either partial or full support from this Environmental Management Science Program (EMSP) project. The project has focused on applying basic and applied scientific methods to improve both the characterization of plutonium (Pu) aerosol deposition in the human respiratory tract and the understanding of the associated health risks. Our modeling research has ranged from stochastic effects in cells (mutations, neoplastic transformation, apoptosis) to cancer induction in humans. Special attention has been given to cancer risk for low-dose exposure to alpha radiation from inhaled Pu-239. We have also conducted modeling research related to high-dose exposure to alpha radiation from inhaled Pu isotopes and the associated risks for deterministic effects. This research is especially timely given new concerns related to possible nuclear terrorist incidents in the United States and elsewhere. The methodology presented in one of our submitted papers (Appendix A) for characterizing the risk of radiation deterministic effects associated with exposure to large internal (alpha, beta, and gamma) and external (gamma) doses is being used by the International Atomic Energy Agency (IAEA) to develop guidance for managing radiological incidents (e.g., dirty bomb incidents) and by Sandia National Laboratories to assess the health consequences of the use of dirty bombs by terrorists. Our dosimetry modeling research has focused largely on weapons-grade Pu (WG Pu), which is comprised of several different isotopes that are primarily alpha emitters. We have mainly focused on the insoluble dioxide form. Our mechanistic modeling research has lead to a revised model for low-dose, radiation induced, neoplastic transformation (an early step in cancer induction). The revised model is called NEOTRANS3, and has facilitated evaluating the expected shape of the dose-response relationship

  19. A method for estimating occupational radiation dose to individuals, using weekly dosimetry data

    SciTech Connect

    Mitchell, T.J.; Ostrouchov, G.; Frome, E.L.; Kerr, G.D.

    1993-12-01

    Statistical analyses of data from epidemiologic studies of workers exposed to radiation have been based on recorded annual radiation doses. It is usually assumed that the annual dose values are known exactly, although it is generally recognized that the data contain uncertainty due to measurement error and bias. We propose the use of a probability distribution to describe an individual`s dose during a specific period of time. Statistical methods for estimating this dose distribution are developed. The methods take into account the ``measurement error`` that is produced by the dosimetry system, and the bias that was introduced by policies that lead to right censoring of small doses as zero. The method is applied to a sample of dose histories obtained from hard copy dosimetry records at Oak Ridge National Laboratory (ORNL). The result of this evaluation raises serious questions about the validity of the historical personnel dosimetry data that is currently being used in low-dose studies of nuclear industry workers. In particular, it appears that there was a systematic underestimation of doses for ORNL workers. This could result in biased estimates of dose-response coefficients and their standard errors.

  20. Space radiation dosimetry on US and Soviet manned missions

    NASA Technical Reports Server (NTRS)

    Parnell, T. A.; Benton, E. V.

    1995-01-01

    Radiation measurements obtained on board U.S. and Soviet spacecraft are presented and discussed. A considerable amount of data has now been collected and analyzed from measurements with a variety of detector types in low-Earth orbit. The objectives of these measurements have been to investigate the dose and Linear Energy Transfer (LET) spectra within the complex shielding of large spacecraft. The shielding modifies the external radiation (trapped protons, electrons, cosmic ray nuclei) which, in turn, is quite dependent on orbital parameters (altitude, inclination). For manned flights, these measurements provide a crew exposure record and a data base for future spacecraft design and flight planning. For the scientific community they provide useful information for planning and analyzing data from experiments with high sensitivity to radiation. In this paper, results of measurements by both passive and active detectors are described. High-LET spectra measurements were obtained by means of plastic nuclear track detectors (PNTD's) while thermoluminescent dosimeters (TLD's) measured the dose.

  1. X-Tream: a novel dosimetry system for Synchrotron Microbeam Radiation Therapy

    NASA Astrophysics Data System (ADS)

    Petasecca, M.; Cullen, A.; Fuduli, I.; Espinoza, A.; Porumb, C.; Stanton, C.; Aldosari, A. H.; Bräuer-Krisch, E.; Requardt, H.; Bravin, A.; Perevertaylo, V.; Rosenfeld, A. B.; Lerch, M. L. F.

    2012-07-01

    Microbeam Radiation Therapy (MRT) is a radiation treatment technique under development for inoperable brain tumors. MRT is based on the use of a synchrotron generated X-ray beam with an extremely high dose rate ( ~ 20 kGy/sec), striated into an array of X-ray micro-blades. In order to advance to clinical trials, a real-time dosimeter with excellent spatial resolution must be developed for absolute dosimetry. The design of a real-time dosimeter for such a radiation scenario represents a significant challenge due to the high photon flux and vertically striated radiation field, leading to very steep lateral dose gradients. This article analyses the striated radiation field in the context of the requirements for temporal dosimetric measurements and presents the architecture of a new dosimetry system based on the use of silicon detectors and fast data acquisition electronic interface. The combined system demonstrates micrometer spatial resolution and microsecond real time readout with accurate sensitivity and linearity over five orders of magnitude of input signal. The system will therefore be suitable patient treatment plan verification and may also be expanded for in-vivo beam monitoring for patient safety during the treatment.

  2. Description of modular devices for the measurement of external dosimetry in radiation protection.

    PubMed

    Genicot, Jean Louis; Boogers, Eric; Van Iersel, Mark

    2015-04-01

    In 2002 the Group of Radiation Dosimetry and Calibration of the Belgian Nuclear Research Centre (SCK•CEN) has developed an experimental device based on the optically stimulated luminescence (OSL) working with Al2O3:C detectors (TLD-500 and Luxel) stimulated with an argon laser. A set of devices made from different modules have been developed to permit external dosimetry measurements with thermoluminescence (TL) and OSL techniques under different conditions. This study describes these measurement devices that can be made with these modules and some of the characteristics of the different systems. These devices present several advantages in terms of measurement possibilities: a small number of modules allow the use of different detection materials (Al2O3:C, BeO, quartz electronic components and tiles) and different measurement methods (TL, CW-OSL and pulsed OSL). Some applications are commented. PMID:25236335

  3. A new highly sensitive low-Z LiF-based OSL phosphor for radiation dosimetry.

    PubMed

    Patil, R R; Gaikwad, S U; More, Y K; Kulkarni, M S; Bhatt, B C; Moharil, S V

    2016-03-01

    A new low-Z lithium fluoride-based optical stimulated luminescent (OSL) phosphor is developed. The phosphor shows good OSL properties, and its sensitivity is comparable with that of the commercial Al2O3:C (Landauer, Inc.) phosphor. For the luminescence averaged over initial 3 s, blue stimulated luminescence (BSL) and green stimulated luminescence (GSL) sensitivities were found to be 0.27 and 4 times, respectively, than that of Al2O3:C (Landauer, Inc.). The BSL decay is fast, and the whole signal decays within 3 s; the GSL decay is relatively slow, and the signal decays in 25 s. The fast decay, good sensitivity, good linearity and its near tissue equivalence (Zeff ∼8.14) will make this phosphor suitable for radiation dosimetry particularly in personnel as well as in medical dosimetry. PMID:26347541

  4. Construction of mouse phantoms from segmented CT scan data for radiation dosimetry studies

    PubMed Central

    Welch, D; Harken, A D; Randers-Pehrson, G; Brenner, D J

    2015-01-01

    We present the complete construction methodology for an anatomically accurate mouse phantom made using materials which mimic the characteristics of tissue, lung, and bone for radiation dosimetry studies. Phantoms were constructed using 2 mm thick slices of tissue equivalent material which was precision machined to clear regions for insertion of lung and bone equivalent material where appropriate. Images obtained using a 3D computed tomography (CT) scan clearly indicate regions of tissue, lung, and bone that match their position within the original mouse CT scan. Additionally, radiographic films are used with the phantom to demonstrate dose mapping capabilities. The construction methodology presented here can be quickly and easily adapted to create a phantom of any specific small animal given a segmented CT scan of the animal. These physical phantoms are a useful tool to examine individual organ dose and dosimetry within mouse systems that are complicated by density inhomogeneity due to bone and lung regions. PMID:25860401

  5. Preclinical radiation dosimetry for the novel SV2A radiotracer [18F]UCB-H

    PubMed Central

    2013-01-01

    Background [18F]UCB-H was developed as a novel radiotracer with a high affinity for synaptic vesicle protein 2A, the binding site for the antiepileptic levetiracetam. The objectives of this study were to evaluate the radiation dosimetry of [18F]UCB-H in a preclinical trial and to determine the maximum injectable dose according to guidelines for human biomedical research. The radiation dosimetry was derived by organ harvesting and dynamic micro positron emission tomography (PET) imaging in mice, and the results of both methods were compared. Methods Twenty-four male C57BL-6 mice were injected with 6.96 ± 0.81 MBq of [18F]UCB-H, and the biodistribution was determined by organ harvesting at 2, 5, 10, 30, 60, and 120 min (n = 4 for each time point). Dynamic microPET imaging was performed on five male C57BL-6 mice after the injection of 9.19 ± 3.40 MBq of [18F]UCB-H. A theoretical dynamic bladder model was applied to simulate urinary excretion. Human radiation dose estimates were derived from animal data using the International Commission on Radiological Protection 103 tissue weighting factors. Results Based on organ harvesting, the urinary bladder wall, liver and brain received the highest radiation dose with a resulting effective dose of 1.88E-02 mSv/MBq. Based on dynamic imaging an effective dose of 1.86E-02 mSv/MBq was calculated, with the urinary bladder wall and liver (brain was not in the imaging field of view) receiving the highest radiation. Conclusions This first preclinical dosimetry study of [18F]UCB-H showed that the tracer meets the standard criteria for radiation exposure in clinical studies. The dose-limiting organ based on US Food and Drug Administration (FDA) and European guidelines was the urinary bladder wall for FDA and the effective dose for Europe with a maximum injectable single dose of approximately 325 MBq was calculated. Although microPET imaging showed significant deviations from organ harvesting, the Pearson’s correlation coefficient

  6. Radiation dosimetry predicts IQ after conformal radiation therapy in pediatric patients with localized ependymoma

    SciTech Connect

    Merchant, Thomas E. . E-mail: thomas.merchant@stjude.org; Kiehna, Erin N.; Li Chenghong; Xiong Xiaoping; Mulhern, Raymond K.

    2005-12-01

    Purpose: To assess the effects of radiation dose-volume distribution on the trajectory of IQ development after conformal radiation therapy (CRT) in pediatric patients with ependymoma. Methods and Materials: The study included 88 patients (median age, 2.8 years {+-} 4.5 years) with localized ependymoma who received CRT (54-59.4 Gy) that used a 1-cm margin on the postoperative tumor bed. Patients were evaluated with tests that included IQ measures at baseline (before CRT) and at 6, 12, 24, 36, 48, and 60 months. Differential dose-volume histograms (DVH) were derived for total-brain, supratentorial-brain, and right and left temporal-lobe volumes. The data were partitioned into three dose intervals and integrated to create variables that represent the fractional volume that received dose over the specified intervals (e.g., V{sub 0-20Gy}, V{sub 20-40Gy}, V{sub 40-65Gy}) and modeled with clinical variables to develop a regression equation to estimate IQ after CRT. Results: A total of 327 IQ tests were performed in 66 patients with infratentorial tumors and 20 with supratentorial tumors. The median follow-up was 29.4 months. For all patients, IQ was best estimated by age (years) at CRT; percent volume of the supratentorial brain that received doses between 0 and 20 Gy, 20 and 40 Gy, and 40 and 65 Gy; and time (months) after CRT. Age contributed significantly to the intercept (p > 0.0001), and the dose-volume coefficients were statistically significant (V{sub 0-20Gy}, p = 0.01; V{sub 20-40Gy}, p < 0.001; V{sub 40-65Gy}, p = 0.04). A similar model was developed exclusively for patients with infratentorial tumors but not supratentorial tumors. Conclusion: Radiation dosimetry can be used to predict IQ after CRT in patients with localized ependymoma. The specificity of models may be enhanced by grouping according to tumor location.

  7. Using polyvinyl chloride dyed with bromocresol purple in radiation dosimetry.

    PubMed

    Kattan, Munzer; al Kassiri, Haroun; Daher, Yarob

    2011-02-01

    Polyvinyl chloride (PVC) dyed with bromocresol purple was investigated as a high-dose radiation dosimeter. The absorbance at 417 nm depends linearly on the dose below 50 kGy. The response depends neither on dose rate nor on the irradiation temperature. The effects of post-irradiation storage in the dark and in indirect sunlight are also discussed.

  8. Neutron radiation dosimetry in high altitude flight personnel.

    PubMed

    Baily, P E

    1982-08-01

    In an attempt to determine cosmic radiation exposure in high altitude NASA flight personnel, eight WB-57F flight crewmen were monitored for a period of six months using a combination radiation dosimeter. Each dosimeter consisted of two thermoluminescent chips capable of measuring gamma dose and one Albedo and two Track Etch neutron dosimeters. A total of 78 flights were monitored consisting of 251 flight hours at altitudes above 14 km (45,000 ft). The maximum yearly dose equivalent measured was 104 mrem, a value well below the Maximum Permissible Dose (MPD) of 5.0 rem/y for occupational exposures and 0.5 rem/y for members of the general public. A discussion of the theory and use of several types of neutron dosimeters is included. PMID:7181814

  9. The radiation oncology workforce: A focus on medical dosimetry

    SciTech Connect

    Robinson, Gregg F.; Mobile, Katherine; Yu, Yan

    2014-07-01

    The 2012 Radiation Oncology Workforce survey was conducted to assess the current state of the entire workforce, predict its future needs and concerns, and evaluate quality improvement and safety within the field. This article describes the dosimetrist segment results. The American Society for Radiation Oncology (ASTRO) Workforce Subcommittee, in conjunction with other specialty societies, conducted an online survey targeting all segments of the radiation oncology treatment team. The data from the dosimetrist respondents are presented in this article. Of the 2573 dosimetrists who were surveyed, 890 responded, which resulted in a 35% segment response rate. Most respondents were women (67%), whereas only a third were men (33%). More than half of the medical dosimetrists were older than 45 years (69.2%), whereas the 45 to 54 years age group represented the highest percentage of respondents (37%). Most medical dosimetrists stated that their workload was appropriate (52%), with respondents working a reported average of 41.7 ± 4 hours per week. Overall, 86% of medical dosimetrists indicated that they were satisfied with their career, and 69% were satisfied in their current position. Overall, 61% of respondents felt that there was an oversupply of medical dosimetrists in the field, 14% reported that supply and demand was balanced, and the remaining 25% felt that there was an undersupply. The medical dosimetrists' greatest concerns included documentation/paperwork (78%), uninsured patients (80%), and insufficient reimbursement rates (87%). This survey provided an insight into the dosimetrist perspective of the radiation oncology workforce. Though an overwhelming majority has conveyed satisfaction concerning their career, the study allowed a spotlight to be placed on the profession's current concerns, such as insufficient reimbursement rates and possible oversupply of dosimetrists within the field.

  10. Genetic and molecular dosimetry of HZE radiation (7-IML-1)

    NASA Technical Reports Server (NTRS)

    Nelson, Gregory A.

    1992-01-01

    The objectives of the study are to determine the kinetics of production and to characterize the unique aspects of genetic and developmental lesion induced in animal cells by radiation present in the space environment. Special attention is given to heavy charged particles. The organism Caenorhabditis elegans, a simple nematode, is used as a model system for a coordinated set of ground-based and flight experiments.

  11. Reported Radiation Overexposure Accidents Worldwide, 1980-2013: A Systematic Review

    PubMed Central

    Coeytaux, Karen; Bey, Eric; Christensen, Doran; Glassman, Erik S.; Murdock, Becky; Doucet, Christelle

    2015-01-01

    Background Radiation overexposure accidents are rare but can have severe long-term health consequences. Although underreporting can be an issue, some extensive literature reviews of reported radiation overexposures have been performed and constitute a sound basis for conclusions on general trends. Building further on this work, we performed a systematic review that completes previous reviews and provides new information on characteristics and trends of reported radiation accidents. Methods We searched publications and reports from MEDLINE, EMBASE, the International Atomic Energy Agency, the International Radiation Protection Association, the United Nations Scientific Committee on the Effects of Atomic Radiation, the United States Nuclear Regulatory Commission, and the Radiation Emergency Assistance Center/Training Site radiation accident registry over 1980-2013. We retrieved the reported overexposure cases, systematically extracted selected information, and performed a descriptive analysis. Results 297 out of 5189 publications and reports and 194 records from the REAC/TS registry met our eligibility criteria. From these, 634 reported radiation accidents were retrieved, involving 2390 overexposed people, of whom 190 died from their overexposure. The number of reported cases has decreased for all types of radiation use, but the medical one. 64% of retrieved overexposure cases occurred with the use of radiation therapy and fluoroscopy. Additionally, the types of reported accidents differed significantly across regions. Conclusions This review provides an updated and broader view of reported radiation overexposures. It suggests an overall decline in reported radiation overexposures over 1980-2013. The greatest share of reported overexposures occurred in the medical fields using radiation therapy and fluoroscopy; this larger number of reported overexposures accidents indicates the potential need for enhanced quality assurance programs. Our data also highlights

  12. What happens when spins meet for ionizing radiation dosimetry?

    NASA Astrophysics Data System (ADS)

    Pavoni, Juliana F.; Neves-Junior, Wellington F. P.; Baffa, Oswaldo

    2016-07-01

    Electron spin resonance (ESR) and magnetic resonance imaging (MRI) can be used to measure radiation dose deposited in different milieu through its effects. Radiation can break chemical bonds and if they produce stable free radicals, ESR can measure their concentration through their spins and a dose can be inferred. Ionizing radiation can also promote polymerization and in this case proton relaxation times can be measured and an image weighed by T2 can be produced giving spatial information about dose. A review of the basics of these applications is presented concluding with an end-to-end test using a composite Gel-Alanine phantom to validate 3-dimensionally dose distribution delivered in a simulation of Volume Modulated Arch Therapy on the simultaneous treatment of multiple brain metastases. The results obtained with the gel and alanine dosimeters are consistent with the expected by the treatment planning system, showing the potential of this multidosimetric approach and validating dosimetrically the multiple brain metastases treatment using VMAT.

  13. Ultrasound Thermometry for Therapy-level Radiation Dosimetry

    NASA Astrophysics Data System (ADS)

    Taylor, Courtney

    2010-03-01

    Radiation oncology is the process of administering a specified dose of radiation to a patient currently receiving treatment for a form of cancer. In this process, it is vital to know the delivered dose for a given radiation beam to correctly treat a patient. The primary reference standard for absorbed dose is established using water calorimetry. The absorbed dose, typically of order 1 Gy (J/kg) at therapy levels, is realized by measuring sub-millikelvin temperature changes using a thermistor in a sensitive Wheatstone bridge. Ultrasound technology has been investigated as an alternative to thermistor measurements since the speed of sound propagation in water varies with temperature. With ultrasonic time-of-flight and highly sensitive phase detection techniques, temperature sensitivity comparable to that of the thermistor bridge has been achieved without introducing non-water materials into the test area. A single ultrasound transducer transmitting and receiving at 5.0 MHz throughout the length of the water phantom, and the phase change of the sound wave was used to determine temperature increase from an irradiative source at specified depths of the phantom. In this experiment, the exposure period was varied from 15s to 160s cyclically by modulating a heat lamp, and a profile of the measured temperature response as a function of the period was obtained using Fourier analysis. Due to the large temperature gradient in the water phantom, measurements are prone to convection which was indeed observed and will be discussed.

  14. Bibliographical database of radiation biological dosimetry and risk assessment: Part 1, through June 1988

    SciTech Connect

    Straume, T.; Ricker, Y.; Thut, M.

    1988-08-29

    This database was constructed to support research in radiation biological dosimetry and risk assessment. Relevant publications were identified through detailed searches of national and international electronic databases and through our personal knowledge of the subject. Publications were numbered and key worded, and referenced in an electronic data-retrieval system that permits quick access through computerized searches on publication number, authors, key words, title, year, and journal name. Photocopies of all publications contained in the database are maintained in a file that is numerically arranged by citation number. This report of the database is provided as a useful reference and overview. It should be emphasized that the database will grow as new citations are added to it. With that in mind, we arranged this report in order of ascending citation number so that follow-up reports will simply extend this document. The database cite 1212 publications. Publications are from 119 different scientific journals, 27 of these journals are cited at least 5 times. It also contains reference to 42 books and published symposia, and 129 reports. Information relevant to radiation biological dosimetry and risk assessment is widely distributed among the scientific literature, although a few journals clearly dominate. The four journals publishing the largest number of relevant papers are Health Physics, Mutation Research, Radiation Research, and International Journal of Radiation Biology. Publications in Health Physics make up almost 10% of the current database.

  15. Alanine-EPR as a transfer standard dosimetry system for low energy X radiation

    NASA Astrophysics Data System (ADS)

    Khoury, H. J.; da Silva, E. J.; Mehta, K.; de Barros, V. S.; Asfora, V. K.; Guzzo, P. L.; Parker, A. G.

    2015-11-01

    The purpose of this paper is to evaluate the use of alanine-EPR as a transfer standard dosimetry system for low energy X radiation, such as that in RS-2400, which operates in the range from 25 to 150 kV and 2 to 45 mA. Two types of alanine dosimeters were investigated. One is a commercial alanine pellets from Aérial-Centre de Ressources Technologiques, France and one was prepared in our laboratory (LMRI-DEN/UFPE). The EPR spectra of the irradiated dosimeters were recorded in the Nuclear Energy Department of UFPE, using a Bruker EMX10 EPR spectrometer operating in the X-band. The alanine-EPR dosimetry system was calibrated in the range of 20-220 Gy in this X-ray field, against an ionization chamber calibrated at the relevant X-ray energy with traceability to PTB. The results showed that both alanine dosimeters presented a linear dose response the same sensitivity, when the EPR signal was normalized to alanine mass. The total uncertainty in the measured dose was estimated to be about 3%. The results indicate that it is possible to use the alanine-EPR dosimetry system for validation of a low-energy X ray irradiator, such as RS-2400.

  16. The new radiation dosimetry for the A-bombs in Hiroshima and Nagasaki

    SciTech Connect

    Kerr, G.D.

    1988-08-18

    Extensive work has been conducted over the past few years to reassess all aspects of the radiation dosimetry for the A-bombs in Hiroshima and Nagasaki. This work has included reviews of the bomb yields, source terms, air transport of neutrons and gamma rays, neutron-induced radioactivity and thermoluminescence in exposed materials, shielding of individuals by buildings, and calculations of organ doses. The results of these theoretical and experimental activities have led to the development of a new dosimetry system which is designated as the Dosimetry System 1986 (DS86). New DS86 estimates of tissue kerma in air and absorbed dose to fifteen organs are available for 94,787 survivors who were either outside and unshielded, outside and shielded by houses, or inside and shielded by houses (64,408 in Hiroshima and 30,379 in Nagasaki). The organ doses are calculated on an age-dependent basis as follows: infants (less than 3 years old at the time of bombing, ATB), children (3 to 12 years old ATB), and adults (more than 12 years old ATB). Work in progress includes the extension of the DS86 system to Nagasaki survivors who were shielded either by terrain or by factory buildings.

  17. Evaluation of 133Xe radiation exposure dosimetry for workers in nuclear medicine laboratories.

    PubMed

    Piltingsrud, H V; Gels, G L

    1982-06-01

    Evaluation of past studies of 133Xe dosimetry and nuclear medicine laboratory air concentrations of 133Xe indicates that significant levels of 133Xe may exist in routine operational environments of a nuclear medicine laboratory. This leads to the question of whether present health physics radiation control methods are adequate to keep occupational personnel exposures within acceptable levels. It would appear that if personnel dosimeters (film and TLD badges) respond properly to the radiation of 133Xe, normal health physics control procedures are probably adequate. If they do not respond adequately, personnel exposures may exceed recommended levels and special instrumentation or administrative procedures are called for. Therefore, the first step in studying potential problems in the subject area is to evaluate the response of a variety of personnel radiation dosimeters to 133Xe. This paper describes the methods and materials used to expose personnel dosimeters to known amounts of 133Xe radiations in an exposure chamber constructed at the BRH Nuclear Medicine Laboratory. Also presented are calculated values for Dose Equivalents (D.E.) in a phantom from external radiation resulting from immersion in clouds having a constant concentration of 133Xe but varying cloud radii. This implies the relative importance of the beta and the X + gamma radiation responses of the personnel dosimeters under various exposure conditions. Results of this study indicate that none of the dosimeter systems evaluated provide adequate performance for use as a primary indicator of the D.E. resulting from 133Xe radiations for a worker in a nuclear medicine laboratory, and that personnel dosimetry considerations in 133Xe-containing atmospheres are very dependent on the radii of the 133Xe clouds.

  18. Radiochromic film dosimetry of HDR {sup 192}Ir source radiation fields

    SciTech Connect

    Aldelaijan, Saad; Mohammed, Huriyyah; Tomic, Nada; Liang Liheng; DeBlois, Francois; Sarfehnia, Arman; Abdel-Rahman, Wamied; Seuntjens, Jan; Devic, Slobodan

    2011-11-15

    Purpose: A radiochromic film based dosimetry system for high dose rate (HDR) Iridium-192 brachytherapy source was described. A comparison between calibration curves established in water and Solid Water was provided. Methods: Pieces of EBT-2 model GAFCHROMIC film were irradiated in both water and Solid Water with HDR {sup 192}Ir brachytherapy source in a dose range from 0 to 50 Gy. Responses of EBT-2 GAFCHROMIC film were compared for irradiations in water and Solid Water by scaling the dose between media through Monte Carlo calculated conversion factor for both setups. To decrease uncertainty in dose delivery due to positioning of the film piece with respect to the radiation source, traceable calibration irradiations were performed in a parallel-opposed beam setup. Results: The EBT-2 GAFCHROMIC film based dosimetry system described in this work can provide an overall one-sigma dose uncertainty of 4.12% for doses above 1 Gy. The ratio of dose delivered to the sensitive layer of the film in water to the dose delivered to the sensitive layer of the film in Solid Water was calculated using Monte Carlo simulations to be 0.9941 {+-} 0.0007. Conclusions: A radiochromic film based dosimetry system using only the green color channel of a flatbed document scanner showed superior precision if used alone in a dose range that extends up to 50 Gy, which greatly decreases the complexity of work. In addition, Solid Water material was shown to be a viable alternative to water in performing radiochromic film based dosimetry with HDR {sup 192}Ir brachytherapy sources.

  19. Review on the characteristics of radiation detectors for dosimetry and imaging

    NASA Astrophysics Data System (ADS)

    Seco, Joao; Clasie, Ben; Partridge, Mike

    2014-10-01

    The enormous advances in the understanding of human anatomy, physiology and pathology in recent decades have led to ever-improving methods of disease prevention, diagnosis and treatment. Many of these achievements have been enabled, at least in part, by advances in ionizing radiation detectors. Radiology has been transformed by the implementation of multi-slice CT and digital x-ray imaging systems, with silver halide films now largely obsolete for many applications. Nuclear medicine has benefited from more sensitive, faster and higher-resolution detectors delivering ever-higher SPECT and PET image quality. PET/MR systems have been enabled by the development of gamma ray detectors that can operate in high magnetic fields. These huge advances in imaging have enabled equally impressive steps forward in radiotherapy delivery accuracy, with 4DCT, PET and MRI routinely used in treatment planning and online image guidance provided by cone-beam CT. The challenge of ensuring safe, accurate and precise delivery of highly complex radiation fields has also both driven and benefited from advances in radiation detectors. Detector systems have been developed for the measurement of electron, intensity-modulated and modulated arc x-ray, proton and ion beams, and around brachytherapy sources based on a very wide range of technologies. The types of measurement performed are equally wide, encompassing commissioning and quality assurance, reference dosimetry, in vivo dosimetry and personal and environmental monitoring. In this article, we briefly introduce the general physical characteristics and properties that are commonly used to describe the behaviour and performance of both discrete and imaging detectors. The physical principles of operation of calorimeters; ionization and charge detectors; semiconductor, luminescent, scintillating and chemical detectors; and radiochromic and radiographic films are then reviewed and their principle applications discussed. Finally, a general

  20. Ce{sup 3+}-doped fibers for remote radiation dosimetry

    SciTech Connect

    Vedda, A.; Chiodini, N.; Di Martino, D.; Fasoli, M.; Keffer, S.; Lauria, A.; Martini, M.; Moretti, F.; Spinolo, G.; Nikl, M.; Solovieva, N.; Brambilla, G.

    2004-12-27

    A radioluminescent (RL) dosimetric system, based on a SiO{sub 2} optical fiber with the core doped by Ce{sup 3+} ions as luminescent activators has been investigated. Structural and optical properties of the luminescent fiber have been studied by Raman, refractive index, RL and scintillation time decay measurements, and compared to those obtained on bulk material. The RL response of a composite fiber made of a short portion of active Ce-doped fiber coupled to a long commercial one has been investigated by x-ray irradiation. A linear RL intensity response has been found in the dose rate interval 6x10{sup -3}-40 mGy/s together with a good radiation hardness, suggesting possible application in low-dose monitoring.

  1. Initial Results from the Radiation Dosimetry Experiment (RaD-X) Balloon Flight Mission

    NASA Technical Reports Server (NTRS)

    Mertens, Christopher J.

    2015-01-01

    The NASA Radiation Dosimetry Experiment (RaD-X) high-altitude balloon mission was successfully launched from Fort Sumner, New Mexico USA on 25 September, 2015. Over 15 hours of science data were obtained from four dosimeters at altitudes above about 25 km. The four dosimeters flown on the RaD-X science payload are a Hawk version 3.0 Tissue Equivalent Proportional Counter (TEPC) manufactured by Far West Technologies, a Liulin dosimeter-spectrometer produced by the Solar Research and Technology Institute, Bulgarian Academy of Sciences, a total ionizing dose detector manufactured by Teledyne Microelectronic Technologies, and the RaySure detector provided by the University of Surrey.

  2. Characterization of a parallel beam CCD optical-CT apparatus for 3D radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Krstajić, Nikola; Doran, Simon J.

    2006-12-01

    This paper describes the initial steps we have taken in establishing CCD based optical-CT as a viable alternative for 3-D radiation dosimetry. First, we compare the optical density (OD) measurements from a high quality test target and variable neutral density filter (VNDF). A modulation transfer function (MTF) of individual projections is derived for three positions of the sinusoidal test target within the scanning tank. Our CCD is then characterized in terms of its signal-to-noise ratio (SNR). Finally, a sample reconstruction of a scan of a PRESAGETM (registered trademark of Heuris Pharma, NJ, Skillman, USA.) dosimeter is given, demonstrating the capabilities of the apparatus.

  3. Radiation dosimetry in digital breast tomosynthesis: report of AAPM Tomosynthesis Subcommittee Task Group 223.

    PubMed

    Sechopoulos, Ioannis; Sabol, John M; Berglund, Johan; Bolch, Wesley E; Brateman, Libby; Christodoulou, Emmanuel; Flynn, Michael; Geiser, William; Goodsitt, Mitchell; Jones, A Kyle; Lo, Joseph Y; Maidment, Andrew D A; Nishino, Kazuyoshi; Nosratieh, Anita; Ren, Baorui; Segars, W Paul; Von Tiedemann, Miriam

    2014-09-01

    The radiation dose involved in any medical imaging modality that uses ionizing radiation needs to be well understood by the medical physics and clinical community. This is especially true of screening modalities. Digital breast tomosynthesis (DBT) has recently been introduced into the clinic and is being used for screening for breast cancer in the general population. Therefore, it is important that the medical physics community have the required information to be able to understand, estimate, and communicate the radiation dose levels involved in breast tomosynthesis imaging. For this purpose, the American Association of Physicists in Medicine Task Group 223 on Dosimetry in Tomosynthesis Imaging has prepared this report that discusses dosimetry in breast imaging in general, and describes a methodology and provides the data necessary to estimate mean breast glandular dose from a tomosynthesis acquisition. In an effort to maximize familiarity with the procedures and data provided in this Report, the methodology to perform the dose estimation in DBT is based as much as possible on that used in mammography dose estimation.

  4. Modeling radiation dosimetry to predict cognitive outcomes in pediatric patients with CNS embryonal tumors including medulloblastoma

    SciTech Connect

    Merchant, Thomas E. . E-mail: thomas.merchant@stjude.org; Kiehna, Erin N.; Li Chenghong; Shukla, Hemant; Sengupta, Saikat; Xiong Xiaoping; Gajjar, Amar; Mulhern, Raymond K.

    2006-05-01

    Purpose: Model the effects of radiation dosimetry on IQ among pediatric patients with central nervous system (CNS) tumors. Methods and Materials: Pediatric patients with CNS embryonal tumors (n = 39) were prospectively evaluated with serial cognitive testing, before and after treatment with postoperative, risk-adapted craniospinal irradiation (CSI) and conformal primary-site irradiation, followed by chemotherapy. Differential dose-volume data for 5 brain volumes (total brain, supratentorial brain, infratentorial brain, and left and right temporal lobes) were correlated with IQ after surgery and at follow-up by use of linear regression. Results: When the dose distribution was partitioned into 2 levels, both had a significantly negative effect on longitudinal IQ across all 5 brain volumes. When the dose distribution was partitioned into 3 levels (low, medium, and high), exposure to the supratentorial brain appeared to have the most significant impact. For most models, each Gy of exposure had a similar effect on IQ decline, regardless of dose level. Conclusions: Our results suggest that radiation dosimetry data from 5 brain volumes can be used to predict decline in longitudinal IQ. Despite measures to reduce radiation dose and treatment volume, the volume that receives the highest dose continues to have the greatest effect, which supports current volume-reduction efforts.

  5. Radiation dosimetry in digital breast tomosynthesis: Report of AAPM Tomosynthesis Subcommittee Task Group 223

    SciTech Connect

    Sechopoulos, Ioannis; Sabol, John M.; Berglund, Johan; Bolch, Wesley E.; Brateman, Libby; Christodoulou, Emmanuel; Goodsitt, Mitchell; Flynn, Michael; Geiser, William; Kyle Jones, A.; Lo, Joseph Y.; Paul Segars, W.; Maidment, Andrew D. A.; Nishino, Kazuyoshi; Nosratieh, Anita; and others

    2014-09-15

    The radiation dose involved in any medical imaging modality that uses ionizing radiation needs to be well understood by the medical physics and clinical community. This is especially true of screening modalities. Digital breast tomosynthesis (DBT) has recently been introduced into the clinic and is being used for screening for breast cancer in the general population. Therefore, it is important that the medical physics community have the required information to be able to understand, estimate, and communicate the radiation dose levels involved in breast tomosynthesis imaging. For this purpose, the American Association of Physicists in Medicine Task Group 223 on Dosimetry in Tomosynthesis Imaging has prepared this report that discusses dosimetry in breast imaging in general, and describes a methodology and provides the data necessary to estimate mean breast glandular dose from a tomosynthesis acquisition. In an effort to maximize familiarity with the procedures and data provided in this Report, the methodology to perform the dose estimation in DBT is based as much as possible on that used in mammography dose estimation.

  6. Radiation Exposure and Thyroid Cancer Risk After the Fukushima Nuclear Power Plant Accident in Comparison with the Chernobyl Accident.

    PubMed

    Yamashita, S; Takamura, N; Ohtsuru, A; Suzuki, S

    2016-09-01

    The actual implementation of the epidemiological study on human health risk from low dose and low-dose rate radiation exposure and the comprehensive long-term radiation health effects survey are important especially after radiological and nuclear accidents because of public fear and concern about the long-term health effects of low-dose radiation exposure have increased considerably. Since the Great East Japan earthquake and the Fukushima Daiichi Nuclear Power Plant accident in Japan, Fukushima Prefecture has started the Fukushima Health Management Survey Project for the purpose of long-term health care administration and medical early diagnosis/treatment for the prefectural residents. Especially on a basis of the lessons learned from the Chernobyl accident, both thyroid examination and mental health care are critically important irrespective of the level of radiation exposure. There are considerable differences between Chernobyl and Fukushima regarding radiation dose to the public, and it is very difficult to estimate retrospectively internal exposure dose from the short-lived radioactive iodines. Therefore, the necessity of thyroid ultrasound examination in Fukushima and the intermediate results of this survey targeting children will be reviewed and discussed in order to avoid any misunderstanding or misinterpretation of the high detection rate of childhood thyroid cancer.

  7. Radiation Exposure and Thyroid Cancer Risk After the Fukushima Nuclear Power Plant Accident in Comparison with the Chernobyl Accident.

    PubMed

    Yamashita, S; Takamura, N; Ohtsuru, A; Suzuki, S

    2016-09-01

    The actual implementation of the epidemiological study on human health risk from low dose and low-dose rate radiation exposure and the comprehensive long-term radiation health effects survey are important especially after radiological and nuclear accidents because of public fear and concern about the long-term health effects of low-dose radiation exposure have increased considerably. Since the Great East Japan earthquake and the Fukushima Daiichi Nuclear Power Plant accident in Japan, Fukushima Prefecture has started the Fukushima Health Management Survey Project for the purpose of long-term health care administration and medical early diagnosis/treatment for the prefectural residents. Especially on a basis of the lessons learned from the Chernobyl accident, both thyroid examination and mental health care are critically important irrespective of the level of radiation exposure. There are considerable differences between Chernobyl and Fukushima regarding radiation dose to the public, and it is very difficult to estimate retrospectively internal exposure dose from the short-lived radioactive iodines. Therefore, the necessity of thyroid ultrasound examination in Fukushima and the intermediate results of this survey targeting children will be reviewed and discussed in order to avoid any misunderstanding or misinterpretation of the high detection rate of childhood thyroid cancer. PMID:27473699

  8. Physical and biological dosimetries of Cf-252 radiation

    SciTech Connect

    Yamashita, H.; Wada, M.; Dokiya, T.; Hashimoto, S.

    1986-01-01

    With a greater availability of Cf-252, more extensive use of Cf-252 as a fast neutron source has become possible. Recently Cf-252 sources containing 300 ..mu..g have become available in a size identical to 1 Ci of Cs-137 and with the use of remotely controlled afterloading apparatus, safe therapy with little exposure to the therapist is now possible. Radiation leakage from the Cf-252 apparatus and from the treatment room was measured with REM-meter and it was possible to reduce the leakage from the treatment room to less than 1 mrem/h (gamma rays) and 0.5 mrem/h (neutrons). Measurement of fast neutrons was made with a twin chamber composed of a tissue equivalent ionization chamber and a carbon ionization chamber. The neutron dose in air and the absorbed dose in tissue equivalent water tank were measured, which showed that in air, neutrons were 70% and photons were 30% of dose. In water, greater distances from the source, neutrons attenuate and gamma rays increase in dose. The results of studies on the skin reaction of mice and sperm cleavage delay time of sea urchins indicated that the RBE ranges from 1.5 to 3.0 using the authors' high dose rate system. Neutrons are remarkably affected by a time factor. With the use of high dose rate sources, the dose rate has become higher, but the overall time has been extended through dose fractionation and the authors have considered it advisable to employ an RBE of 3-4 in their studies.

  9. A portable electronic system for radiation dosimetry using electrets

    NASA Astrophysics Data System (ADS)

    Cruvinel, P. E.; Mascarenhas, S.; Cameron, J.

    1990-02-01

    An electret dosimeter with a cylindrical active volume has been introduced by Mascarenhas and collaborators [Proc. 10th Anniversary Conf. 1969-1979, Associacâo Brasileira de Fisicos em Medicina, p. 488; Topics Appl. Phys. 33 (1987) 321] for possible use in personnel and area monitoring. The full energy response curve as well as the degree of reproducibility and accuracy of the dosimeter are reported in a previous report [O. Guerrini, Master Science Thesis, São Carlos, USP-IFQSC (1982)]. For dimensions similar to those of the common pen dosimeter, the electret has a total surface charge of the order of 10 -9 C and it has a readout sensitivity of the order of 10 -5 Gy with a useful range of 5 × 10 -2 Gy. In this paper we describe a portable electronic system to measure X and γ-rays using a cylindrical electret ionization chamber. It uses commercially available operational amplifiers, and charge measurements can also be made by connecting a suitable capacitor in the feedback loop. With this system it is possible to measure equivalent surface charges up to (19.99±0.01) on the dosimeter. The readout doses are shown on a 3 {1}/{2} digit liquid crystal display (LCD). We have used complementary metal oxide semiconductor (CMOS) and bipolar metal oxide semiconductor (BiMOS) operatonal amplifier devices in the system's design. This choice provides small power consumption and is ideal for battery powered instruments. Furthermore the instrument is ideally suited for in situ measurements of X and γ radiation using a cylindrical electret ionization chamber.

  10. SU-D-213-06: Dosimetry of Modulated Electron Radiation Therapy Using Fricke Gel Dosimeter

    SciTech Connect

    Gawad, M Abdel; Elgohary, M; Hassaan, M; Emam, M; Desouky, O; Eldib, A; Ma, C

    2015-06-15

    Purpose: Modulated electron radiation therapy (MERT) has been proposed as an effective modality for treatment of superficial targets. MERT utilizes multiple beams of different energies which are intensity modulated to deliver optimized dose distribution. Energy independent dosimeters are thus needed for quantitative evaluations of MERT dose distributions and measurements of absolute doses delivered to patients. Thus in the current work we study the feasibility of Fricke gel dosimeters in MERT dosimetry. Methods: Batches of radiation sensitive Fricke gel is fabricated and poured into polymethyl methacrylate cuvettes. The samples were irradiated in solid water phantom and a thick layer of bolus was used as a buildup. A spectrophotometer system was used for measuring the color changes (the absorbance) before and after irradiation and then we calculate net absorbance. We constructed calibration curves to relate the measured absorbance in terms of absorbed dose for all available electron energies. Dosimetric measurements were performed for mixed electron beam delivery and we also performed measurement for segmented field delivery with the dosimeter placed at the junction of two adjacent electron beams of different energies. Dose measured by our gel dosimetry is compared to that calculation from our precise treatment planning system. We also initiated a Monte Carlo study to evaluate the water equivalence of our dosimeters. MCBEAM and MCSIM codes were used for treatment head simulation and phantom dose calculation. PDDs and profiles were calculated for electron beams incident on a phantom designed with 1cm slab of Fricke gel. Results: The calibration curves showed no observed energy dependence with all studied electron beam energies. Good agreement was obtained between dose calculated and that obtained by gel dosimetry. Monte Carlo results illustrated the tissue equivalency of our Gel dosimeters. Conclusion: Fricke Gel dosimeters represent a good option for the dosimetric

  11. [New dosimetry system based on the thermoluminescence method for evaluation of ionizing radiation doses to workers of the health centers].

    PubMed

    Urban, Paweł; Skubacz, Krystian

    2015-01-01

    In different areas of industry, science and in the greater extend medicine, plenty of devices intended for production of ionizing radiation or containing sources of such radiation found application. Such situation causes the necessity to control such kind of hazards. Currently, the most popular technique for detection of ionizing radiation is the method based on the thermoluminescence phenomena. Within the frame of this work, a new Panasonic's dosimetry system based on thermoluminescence dosimeters, intended for assessment of doses in mixed radiation fields of various energies is presented. In addition, the measured dosimetry quantities and problems connected with monitoring of radiation hazard in mixed fields (commonly present in medical sector) are characterized. In orderto verify measurement capabilities of the new system the irradiations of dosimeters with ionizing radiation of different energies have been done.

  12. Radiation accident preparedness: a European approach to train physicians to manage mass radiation casualties.

    PubMed

    Hotz, Mark E; Fliedner, Theodor M; Meineke, Viktor

    2010-06-01

    Mass casualties after radiation exposure pose an enormous logistical challenge for national health services worldwide. Successful medical treatment of radiation victims requires that a plan for medical radiation accident management be established, that the plan be tested in regular exercises, and that it be found to be effective in the management of actual victims of a radiological incident. These activities must be provided by a critical mass of clinicians who are knowledgeable in the diagnosis and management of radiation injury. Here, we describe efforts to provide education to physicians engaged in clinical transplantation. Following intensive discussion among European experts at the International Center for Advanced Studies in Health Sciences and Services, University of Ulm, Germany, an advanced training program on "radiation syndromes" was developed for physicians with experience in the management of patients with pancytopenia and multi-organ failure occurring in a transplant setting. The first European advanced training course using this educational tool took place at Oberschleissheim, Germany, on 28-30 November 2007. Small group discussions and practical exercises were employed to teach general principles and unique features of whole body radiation exposure. Topics included the biological effects of contamination, incorporation of radionuclides, clinical consequences of exposure to radiation, and approaches to medical management. Recommendations resulting from this initial educational experience include (1) provision of funding for attending, conducting and updating the curriculum, and (2) development of an educational program that is harmonized among European and non-European experts in medical management of mass casualties from a radionuclear incident. PMID:20445401

  13. Radiation protection issues on preparedness and response for a severe nuclear accident: experiences of the Fukushima accident.

    PubMed

    Homma, T; Takahara, S; Kimura, M; Kinase, S

    2015-06-01

    Radiation protection issues on preparedness and response for a severe nuclear accident are discussed in this paper based on the experiences following the accident at Fukushima Daiichi nuclear power plant. The criteria for use in nuclear emergencies in the Japanese emergency preparedness guide were based on the recommendations of International Commission of Radiological Protection (ICRP) Publications 60 and 63. Although the decision-making process for implementing protective actions relied heavily on computer-based predictive models prior to the accident, urgent protective actions, such as evacuation and sheltering, were implemented effectively based on the plant conditions. As there were no recommendations and criteria for long-term protective actions in the emergency preparedness guide, the recommendations of ICRP Publications 103, 109, and 111 were taken into consideration in determining the temporary relocation of inhabitants of heavily contaminated areas. These recommendations were very useful in deciding the emergency protective actions to take in the early stages of the Fukushima accident. However, some suggestions have been made for improving emergency preparedness and response in the early stages of a severe nuclear accident.

  14. Radiation protection issues on preparedness and response for a severe nuclear accident: experiences of the Fukushima accident.

    PubMed

    Homma, T; Takahara, S; Kimura, M; Kinase, S

    2015-06-01

    Radiation protection issues on preparedness and response for a severe nuclear accident are discussed in this paper based on the experiences following the accident at Fukushima Daiichi nuclear power plant. The criteria for use in nuclear emergencies in the Japanese emergency preparedness guide were based on the recommendations of International Commission of Radiological Protection (ICRP) Publications 60 and 63. Although the decision-making process for implementing protective actions relied heavily on computer-based predictive models prior to the accident, urgent protective actions, such as evacuation and sheltering, were implemented effectively based on the plant conditions. As there were no recommendations and criteria for long-term protective actions in the emergency preparedness guide, the recommendations of ICRP Publications 103, 109, and 111 were taken into consideration in determining the temporary relocation of inhabitants of heavily contaminated areas. These recommendations were very useful in deciding the emergency protective actions to take in the early stages of the Fukushima accident. However, some suggestions have been made for improving emergency preparedness and response in the early stages of a severe nuclear accident. PMID:25915551

  15. Radiation dosimetry measurements during U.S. Space Shuttle missions with the RME-III.

    PubMed

    Golightly, M J; Hardy, K; Quam, W

    1994-01-01

    Time-resolved radiation dosimetry measurements inside the crew compartment have been made during recent Shuttle missions with the U.S. Air Force Radiation Monitoring Equipment-III (RME-III), a portable battery-powered four-channel tissue equivalent proportional counter. Results from the first six missions are presented and discussed. Half of the missions had orbital inclinations of 28.5 degrees with the remainder at inclinations of 57 degrees or greater; altitudes ranged from 300 to 600 km. The determined dose equivalent rates ranged from 70 to 5300 microSv/day. The RME-III measurements are in good agreement with other dosimetry measurements made aboard the vehicles. Measurements indicate that medium- and high-LET particles contribute less than 2% of the particle fluence for all missions, but up to 50% of the dose equivalent, depending on the spacecraft's altitude and orbital inclination. Isocontours of fluence, dose and dose equivalent rate have been developed from measurements made during the STS-28 mission. The drift rate of the South Atlantic Anomaly is estimated to be 0.49 degrees W/yr and 0.12 degrees N/yr. The calculated trapped proton and GCR dose for the STS-28 mission was significantly lower than the measured values.

  16. Thermoluminescence characteristics of Ge-doped optical fibers with different dimensions for radiation dosimetry.

    PubMed

    Begum, Mahfuza; Rahman, A K M Mizanur; Abdul-Rashid, H A; Yusoff, Z; Begum, Mahbuba; Mat-Sharif, K A; Amin, Y M; Bradley, D A

    2015-06-01

    Important thermoluminescence (TL) properties of five (5) different core sizes Ge-doped optical fibers have been studied to develop new TL material with better response. These are drawn from same preform applying different speed and tension during drawing phase to produce Ge-doped optical fibers with five (5) different core sizes. The results of the investigations are also compared with most commonly used standard TLD-100 chips (LiF:Mg,Ti) and commercial multimode Ge-doped optical fiber (Yangtze Optical Fiber, China). Scanning Electron Microscope (SEM) and EDX analysis of the fibers are also performed to map Ge distribution across the deposited region. Standard Gamma radiation source in Secondary Standard Dosimetry Lab (SSDL) was used for irradiation covering dose range from 1Gy to 10Gy. The essential dosimetric parameters that have been studied are TL linearity, reproducibility and fading. Prior to irradiation all samples ∼0.5cm length are annealed at temperature of 400°C for 1h period to standardize their sensitivities and background. Standard TLD-100 chips are also annealed for 1h at 400°C and subsequently 2h at 100°C to yield the highest sensitivity. TL responses of these fibers show linearity over a wide gamma radiation dose that is an important property for radiation dosimetry. Among all fibers used in this study, 100μm core diameter fiber provides highest response that is 2.6 times than that of smallest core (20μm core) optical fiber. These fiber-samples demonstrate better response than commercial multi-mode optical fiber and also provide low degree of fading about 20% over a period of fifteen days for gamma radiation. Effective atomic number (Zeff) is found in the range (13.25-13.69) which is higher than soft tissue (7.5) however within the range of human-bone (11.6-13.8). All the fibers can also be re-used several times as a detector after annealing. TL properties of the Ge-doped optical fibers indicate promising applications in ionizing radiation

  17. Radiation effects on MOS devices - dosimetry, annealing, irradiation sequence, and sources

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.; Brucker, G. J.; Van Gunten, O.; Knudson, A. R.; Jordan, T. M.

    1983-01-01

    This paper reports on some investigations of dosimetry, annealing, irradiation sequences, and radioactive sources, involved in the determination of radiation effects on MOS devices. Results show that agreement in the experimental and theoretical surface to average doses support the use of thermo-luminescent dosimeters (manganese activated calcium fluoride) in specifying the surface dose delivered to thin gate insulators of MOS devices. Annealing measurements indicate the existence of at least two energy levels,,s or a activation energies, for recovery of soft oxide MOS devices after irradiation by electrons, protons, and gammas. Damage sensitivities of MOS devices were found to be independent of combinations and sequences of radiation type or energies. Comparison of various gamma sources indicated a small dependence of damage sensitivity on the Cobalt facility, but a more significant dependence in the case of the Cesium source. These results were attributed to differences in the spectral content of the several sources.

  18. Setup verification and in vivo dosimetry during intraoperative radiation therapy (IORT) for prostate cancer

    SciTech Connect

    Soriani, Antonella; Landoni, Valeria; Marzi, Simona; Iaccarino, Giuseppe; Saracino, Biancamaria; Arcangeli, Giorgio; Benassi, Marcello

    2007-08-15

    The purpose of this study was to check the setup and dose delivered to the patients during intraoperative electron beam radiation therapy (IORT) for prostate cancer. Twenty eight patients underwent IORT after radical prostatectomy for prostate cancer by means of a dedicated mobile accelerator, Novac7 (by Hitesys, SpA, Italy). A 9 MeV electron beam at high dose per pulse was used. Eighteen patients received IORT at escalating doses of 16, 18, and 20 Gy at 85% isodose, six patients for each dose level. Further, ten patients received 20 Gy at 85% isodose. The electron applicator position was checked in all cases by means of two orthogonal images obtained with brilliance intensifier. Target and organ at risk doses were measured in vivo by a MOSFETs dosimetry system. MOSFETs and microMOSFET dosimeters were inserted into sterile catheters and directly positioned into the rectal lumen, for ten patients, and into the bladder to urethra anastomosis, in the last 14 cases. Verification at 0 deg. led to very few adjustments of setup while verifications at 90 deg. often suggested to bring the applicator closer to the target. In vivo dosimetry showed an absorbed dose into the rectum wall {<=}1% of the total dose. The average dose value inside the anastomosis, for the 12 patients analyzed, was 23.7 Gy with a standard deviation of {+-}7.6%, when the prescription was 20 Gy at 85% isodose. Using a C-arm mobile image intensifier, it is possible to assess if the positioning is correct and safe. Radio-opaque clips and liquid were necessary to obtain good visible images. In vivo MOSFETs dosimetry is feasible and reliable. A satisfactory agreement between measured and expected doses was found.

  19. Radiation effects analysis in a group of interventional radiologists using biological and physical dosimetry methods.

    PubMed

    Ramos, M; Montoro, A; Almonacid, M; Ferrer, S; Barquinero, J F; Tortosa, R; Verdú, G; Rodríguez, P; Barrios, L L; Villaescusa, J I

    2010-08-01

    Interventional radiologists and staff members are frequently exposed to protracted and fractionated low doses of ionizing radiation, which extend during all their professional activities. These exposures can derive, due to the effects of direct and scattered radiation, in deterministic effects (radiodermitis, aged skin, cataracts, telangiectasia in nasal region, vasocellular epitelioms, hands depilation) and/or stochastic ones (cancer incidence). A methodology has been proposed for estimating the radiation risk or detriment from a group of six exposed interventional radiologists of the Hospital Universitario La Fe (Valencia, Spain), which had developed general exposition symptoms attributable to deterministic effects of ionizing radiation. Equivalent doses have been periodically registered using TLD's and wrist dosimeters, H(p)(10) and H(p)(0.07), respectively, and estimated through the observation of translocations in lymphocytes of peripheral blood (biological methods), by extrapolating the yield of translocations to their respective dose-effect curves. The software RADRISK has been applied for estimating radiation risks in these occupational radiation exposures. This software is based on transport models from epidemiological studies of population exposed to external sources of ionizing radiation, such as Hiroshima and Nagasaki atomic bomb survivors [UNSCEAR, Sources and effects of ionizing radiation: 2006 report to the general assembly, with scientific annexes. New York: United Nations; 2006]. The minimum and maximum average excess ratio for skin cancer has been, using wrist physical doses, of [1.03x10(-3), 5.06x10(-2)], concluding that there is not an increased risk of skin cancer incidence. The minimum and maximum average excess ratio for leukemia has been, using TLD physical doses, of [7.84x10(-2), 3.36x10(-1)], and using biological doses, of [1.40x10(-1), 1.51], which is considerably higher than incidence rates, showing an excess radio-induced risk of

  20. Radiation effects in interventional radiology using biological and physical dosimetry methods: a case-control study.

    PubMed

    Ramos, Miguel; Montoro, Alegria; Almonacid, Miguel; Ferrer, Silvia; Barquinero, Joan Francesc; Tortosa, Ricardo; Verdú, Gumersindo; Rodríguez, Pilar; Barrios, Lleonard; Villaescusa, Juan Ignacio

    2008-01-01

    Interventional radiologists and staff members are frequently exposed to protracted and fractionated low doses of ionizing radiation, which extend during all their professional activities. These exposures can derive, due to the irradiation of skin tissues and peripheral blood, in deterministic effects (radiodermitis, aged skin, hands depilation) or stochastic ones (skin and non-solid cancers incidence). Epidemiological studies of population exposed to ionizing radiation provide information of radio-induced effects. The radiation risk or radiological detriment has been estimated from a group of six exposed interventionist radiologists of the Hospital La Fe (Valencia, Spain). Dosimetry has been periodically registered from TLDs and wrist dosimeters (physical methods) and estimated through translocations in lymphocytes of peripheral blood (biological methods), by extrapolating the yield of translocations to their respective dose-effect curves. The probability of non-melanoma skin cancer and leukaemia (acute myelogenous, acute lymphocytic and chronic myelogenous leukaemia) incidence has been estimated through the software RADRISK. This software is based on a transport model from epidemiological studies of population exposed to external low-LET ionizing radiation [1]. Other non-solid carcinomas have not been considered due to their low statistical power, such as myeloid and non-Hodgkin lymphomas. The discrepancies observed between the physically recorded doses and biological estimated doses could indicate that exposed workers did not always wear their dosimeters or these dosimeters were not always exposed to the radiation field.

  1. Radiation dosimetry data management using VAX C, FMS, RMS, DCL, and Oracle

    SciTech Connect

    Voltin, M.J. Jr.; Martin, A.K.

    1991-01-01

    The External Dosimetry Badge System was developed to support the radiation protection program at Los Alamos National Laboratory. The radiation protection program is responsible for monitoring external radiation exposures to approximately 7,500 Laboratory employees, visitors and contractors each month. External radiation exposure is measured using thermoluminescent dosimeters (TLDs). The system is used to control the assembly and distribution of TLD badges. The system monitors badge return and disassembly at the end of each month, and analyzes the TLDs to determine individual radiation exposure levels. Results are reported and stored in a database designed to maintain detailed individual exposure records. The system maintains a complete history of annual summaries for external exposures. The system is user-friendly with user prompts, menus, and extensive help functions. The completely menu-driven system uses VAX C, VAX Forms Management System, VMS Record Management Services, VMS Digital Command Language, and the Oracle Relational Database Management System. Design and development issues faced, and methods and techniques used in developing the system will be described. Topics discussed include consistent user interface design approaches, considerations for using VAX/VMS programming tools versus Oracle development tools to develop and implement the application, and overall system benefits. 3 refs.

  2. SU-E-QI-15: Single Point Dosimetry by Means of Cerenkov Radiation Energy Transfer (CRET)

    SciTech Connect

    Volotskova, O; Jenkins, C; Xing, L

    2014-06-15

    Purpose: Cerenkov light is generated when a charged particles with energy greater then 250 keV, moves faster than the speed of light in a given medium. Both x-ray photons and electrons produce optical Cerenkov photons during the static megavoltage linear accelerator (LINAC) operational mode. Recently, Cerenkov radiation gained considerable interest as possible candidate as a new imaging modality. Optical signals generated by Cerenkov radiation may act as a surrogate for the absorbed superficial radiation dose. We demonstrated a novel single point dosimetry method for megavoltage photon and electron therapy utilizing down conversion of Cerenkov photons. Methods: The custom build signal characterization system was used: a sample holder (probe) with adjacent light tight compartments was connected via fiber-optic cables to a photon counting photomultiplier tube (PMT). One compartment contains a medium only while the other contains medium and red-shifting nano-particles (Q-dots, nanoclusters). By taking the difference between the two signals (Cerenkov photons and CRET photons) we obtain a measure of the down-converted light, which we expect to be proportional to dose as measured with an adjacent ion chamber. Experimental results are compared to Monte Carlo simulations performed using the GEANT4 code. Results: The signal correlation between CR signal, CRET readings and dose produced by LINAC at a single point were investigated. The experimental results were compared with simulations. The dose linearity, signal to noise ratio and dose rate dependence were tested with custom build CRET based probe. Conclusion: Performance characteristics of the proposed single point CRET based probe were evaluated. The direct use of the induced Cerenkov emission and CRET in an irradiated single point volume as an indirect surrogate for the imparted dose was investigated. We conclude that CRET is a promising optical based dosimetry method that offers advantages over those already proposed.

  3. Radiation accidents and their management: emphasis on the role of nuclear medicine professionals

    PubMed Central

    Novruzov, Fuad; Vinjamuri, Sobhan

    2014-01-01

    Large-scale radiation accidents are few in number, but those that have occurred have subsequently led to strict regulation in most countries. Here, different accident scenarios involving exposure to radiation have been reviewed. A triage of injured persons has been summarized and guidance on management has been provided in accordance with the early symptoms. Types of casualty to be expected in atomic blasts have been discussed. Management at the scene of an accident has been described, with explanation of the role of the radiation protection officer, the nature of contaminants, and monitoring for surface contamination. Methods for early diagnosis of radiation injuries have been then described. The need for individualization of treatment according to the nature and grade of the combined injuries has been emphasized, and different approaches to the treatment of internal contamination have been presented. The role of nuclear medicine professionals, including physicians and physicists, has been reviewed. It has been concluded that the management of radiation accidents is a very challenging process and that nuclear medicine physicians have to be well organized in order to deliver suitable management in any type of radiation accident. PMID:25004166

  4. Radiation accidents and their management: emphasis on the role of nuclear medicine professionals.

    PubMed

    Bomanji, Jamshed B; Novruzov, Fuad; Vinjamuri, Sobhan

    2014-10-01

    Large-scale radiation accidents are few in number, but those that have occurred have subsequently led to strict regulation in most countries. Here, different accident scenarios involving exposure to radiation have been reviewed. A triage of injured persons has been summarized and guidance on management has been provided in accordance with the early symptoms. Types of casualty to be expected in atomic blasts have been discussed. Management at the scene of an accident has been described, with explanation of the role of the radiation protection officer, the nature of contaminants, and monitoring for surface contamination. Methods for early diagnosis of radiation injuries have been then described. The need for individualization of treatment according to the nature and grade of the combined injuries has been emphasized, and different approaches to the treatment of internal contamination have been presented. The role of nuclear medicine professionals, including physicians and physicists, has been reviewed. It has been concluded that the management of radiation accidents is a very challenging process and that nuclear medicine physicians have to be well organized in order to deliver suitable management in any type of radiation accident.

  5. Study of runaway electrons using dosimetry of hard x-ray radiations in Damavand tokamak.

    PubMed

    Rasouli, C; Pourshahab, B; Hosseini Pooya, S M; Orouji, T; Rasouli, H

    2014-05-01

    In this work several studies have been conducted on hard x-ray emissions of Damavand tokamak based on radiation dosimetry using the Thermoluminescence method. The goal was to understand interactions of runaway electrons with plasma particles, vessel wall, and plasma facing components. Total of 354 GR-200 (LiF:Mg,Cu,P) thermoluminescence dosimeter (TLD) crystals have been placed on 118 points--three TLDs per point--to map hard x-ray radiation doses on the exterior of the vacuum vessel. Results show two distinctive levels of x-ray radiations doses on the exterior of the vessel. The low-dose area on which measured dose is about 0.5 mSv/shot. In the low-dose area there is no particular component inside the vessel. On the contrary, on high-dose area of the vessel, x-ray radiations dose exceeds 30 mSv/shot. The high-dose area coincides with the position of limiters, magnetic probe ducts, and vacuum vessel intersections. Among the high-dose areas, the highest level of dose is measured in the position of the limiter, which could be due to its direct contact with the plasma column and with runaway electrons. Direct collisions of runaway electrons with the vessel wall and plasma facing components make a major contribution for production of hard x-ray photons in Damavand tokamak.

  6. Study of runaway electrons using dosimetry of hard x-ray radiations in Damavand tokamak

    NASA Astrophysics Data System (ADS)

    Rasouli, C.; Pourshahab, B.; Hosseini Pooya, S. M.; Orouji, T.; Rasouli, H.

    2014-05-01

    In this work several studies have been conducted on hard x-ray emissions of Damavand tokamak based on radiation dosimetry using the Thermoluminescence method. The goal was to understand interactions of runaway electrons with plasma particles, vessel wall, and plasma facing components. Total of 354 GR-200 (LiF:Mg,Cu,P) thermoluminescence dosimeter (TLD) crystals have been placed on 118 points - three TLDs per point - to map hard x-ray radiation doses on the exterior of the vacuum vessel. Results show two distinctive levels of x-ray radiations doses on the exterior of the vessel. The low-dose area on which measured dose is about 0.5 mSv/shot. In the low-dose area there is no particular component inside the vessel. On the contrary, on high-dose area of the vessel, x-ray radiations dose exceeds 30 mSv/shot. The high-dose area coincides with the position of limiters, magnetic probe ducts, and vacuum vessel intersections. Among the high-dose areas, the highest level of dose is measured in the position of the limiter, which could be due to its direct contact with the plasma column and with runaway electrons. Direct collisions of runaway electrons with the vessel wall and plasma facing components make a major contribution for production of hard x-ray photons in Damavand tokamak.

  7. Study of runaway electrons using dosimetry of hard x-ray radiations in Damavand tokamak

    SciTech Connect

    Rasouli, C.; Pourshahab, B.; Rasouli, H.; Hosseini Pooya, S. M.; Orouji, T.

    2014-05-15

    In this work several studies have been conducted on hard x-ray emissions of Damavand tokamak based on radiation dosimetry using the Thermoluminescence method. The goal was to understand interactions of runaway electrons with plasma particles, vessel wall, and plasma facing components. Total of 354 GR-200 (LiF:Mg,Cu,P) thermoluminescence dosimeter (TLD) crystals have been placed on 118 points – three TLDs per point – to map hard x-ray radiation doses on the exterior of the vacuum vessel. Results show two distinctive levels of x-ray radiations doses on the exterior of the vessel. The low-dose area on which measured dose is about 0.5 mSv/shot. In the low-dose area there is no particular component inside the vessel. On the contrary, on high-dose area of the vessel, x-ray radiations dose exceeds 30 mSv/shot. The high-dose area coincides with the position of limiters, magnetic probe ducts, and vacuum vessel intersections. Among the high-dose areas, the highest level of dose is measured in the position of the limiter, which could be due to its direct contact with the plasma column and with runaway electrons. Direct collisions of runaway electrons with the vessel wall and plasma facing components make a major contribution for production of hard x-ray photons in Damavand tokamak.

  8. Development and validation of a GEANT4 radiation transport code for CT dosimetry.

    PubMed

    Carver, D E; Kost, S D; Fernald, M J; Lewis, K G; Fraser, N D; Pickens, D R; Price, R R; Stabin, M G

    2015-04-01

    The authors have created a radiation transport code using the GEANT4 Monte Carlo toolkit to simulate pediatric patients undergoing CT examinations. The focus of this paper is to validate their simulation with real-world physical dosimetry measurements using two independent techniques. Exposure measurements were made with a standard 100-mm CT pencil ionization chamber, and absorbed doses were also measured using optically stimulated luminescent (OSL) dosimeters. Measurements were made in air with a standard 16-cm acrylic head phantom and with a standard 32-cm acrylic body phantom. Physical dose measurements determined from the ionization chamber in air for 100 and 120 kVp beam energies were used to derive photon-fluence calibration factors. Both ion chamber and OSL measurement results provide useful comparisons in the validation of the Monte Carlo simulations. It was found that simulated and measured CTDI values were within an overall average of 6% of each other. PMID:25706135

  9. Development of europium doped BaSO4 TL OSL dual phosphor for radiation dosimetry applications

    NASA Astrophysics Data System (ADS)

    Patle, Anita; Patil, R. R.; Kulkarni, M. S.; Bhatt, B. C.; Moharil, S. V.

    2015-08-01

    This paper presents the results on the preparation and characterization of Europium-doped Barium sulfate (BaSO4: Eu) TL /OSL dual phosphor. The OSL sensitivity was found to be 11% of the commercially available Al2O3: C, using area integration method. The sample also shows good TL sensitivity and the dosimetric peak appears around 190°C with a shoulder at 282°C. After OSL readout, No change in the TL glow curve is observed. Since the observed TL peaks are not responsible for the observed OSL, good OSL as well as TL sensitivity and low fading will make this phosphor suitable for applications in radiation dosimetry using OSL as well as TL.

  10. A measurement of the radiation dose to LDEF by passive dosimetry

    NASA Technical Reports Server (NTRS)

    Blake, J. B.; Imamoto, S. S.

    1993-01-01

    The results from a pair of thermoluminescent dosimeter experiments flown aboard the Long Duration Exposure Facility (LDEF) show an integrated dose several times smaller than that predicted by the NASA environmental models for shielding thicknesses much greater than 0.10 gm/sq cm aluminum. For thicknesses between 0.01 and 0.1 gm/sq cm, the measured dose was in agreement with predictions. The Space and Environment Technology Center of The Aerospace Corporation fielded two related experiments on LDEF to measure the energetic radiation dose by means of passive dosimetry. The sensors were LiF thermoluminescent dosimeters mounted behind various thicknesses of shielding. The details of the experiment are described first, followed by the results of the observations. A comparison is made with the predictions based upon the NASA environmental models and the actual mission profile flown by LDEF; conclusions follow.

  11. Development and validation of a GEANT4 radiation transport code for CT dosimetry

    PubMed Central

    Carver, DE; Kost, SD; Fernald, MJ; Lewis, KG; Fraser, ND; Pickens, DR; Price, RR; Stabin, MG

    2014-01-01

    We have created a radiation transport code using the GEANT4 Monte Carlo toolkit to simulate pediatric patients undergoing CT examinations. The focus of this paper is to validate our simulation with real-world physical dosimetry measurements using two independent techniques. Exposure measurements were made with a standard 100-mm CT pencil ionization chamber, and absorbed doses were also measured using optically stimulated luminescent (OSL) dosimeters. Measurements were made in air, a standard 16-cm acrylic head phantom, and a standard 32-cm acrylic body phantom. Physical dose measurements determined from the ionization chamber in air for 100 and 120 kVp beam energies were used to derive photon-fluence calibration factors. Both ion chamber and OSL measurement results provide useful comparisons in the validation of our Monte Carlo simulations. We found that simulated and measured CTDI values were within an overall average of 6% of each other. PMID:25706135

  12. Radiation dosimetry using decreasing TL intensity in a few variety of silicate crystals.

    PubMed

    Watanabe, Shigueo; Cano, Nilo F; Gundu Rao, T K; Oliveira, Letícia M; Carmo, Lucas S; Chubaci, Jose F D

    2015-11-01

    This study shows that there are some ionic crystals which after irradiation with high gamma dose Dm and subsequent irradiation with low doses ranging up to 500Gy present a decreasing TL intensity as dose increases. This interesting feature can be used as a calibration curve in radiation dosimetry. Such behavior can be found in green quartz, three varieties of beryl and pink tourmaline. In all these silicate crystals it can be shown that irradiation with increasing γ-dose there is a dose Dm for which the TL intensity is maximum. Of course, Dm varies depending on the crystal and irradiated crystal with the dose Dm is stable. If one of these crystals is taken and irradiated with doses from low values up to 400-500Gy, a curve of decreasing TL intensity is obtained; such a curve can be used as a calibration curve. PMID:26277189

  13. Synthesis and luminescence properties of KSrPO4:Eu2+ phosphor for radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Palan, C. B.; Bajaj, N. S.; Omanwar, S. K.

    2016-05-01

    The KSrPO4:Eu phosphor was synthesized via solid state method. The structural and morphological characterizations were done through XRD (X-ray diffraction) and SEM (Scanning Electronic Microscope). Additionally, the photoluminescence (PL), thermoluminescence (TL) and optically Stimulated luminescence (OSL) properties of powder KSrPO4:Eu were studied. The PL spectra show blue emission under near UV excitation. It was advocated that KSrPO4:Eu phosphor not only show OSL sensitivity (0.47 times) but also gives faster decay in OSL signals than that of Al2O3:C (BARC) phosphor. The TL glow curve consist of two shoulder peaks and the kinetics parameters such as activation energy and frequency factors were determined by using peak shape method and also photoionization cross-sections of prepared phosphor was calculated. The radiation dosimetry properties such as minimum detectable dose (MDD), dose response and reusability were reported.

  14. Radiation dosimetry using decreasing TL intensity in a few variety of silicate crystals.

    PubMed

    Watanabe, Shigueo; Cano, Nilo F; Gundu Rao, T K; Oliveira, Letícia M; Carmo, Lucas S; Chubaci, Jose F D

    2015-11-01

    This study shows that there are some ionic crystals which after irradiation with high gamma dose Dm and subsequent irradiation with low doses ranging up to 500Gy present a decreasing TL intensity as dose increases. This interesting feature can be used as a calibration curve in radiation dosimetry. Such behavior can be found in green quartz, three varieties of beryl and pink tourmaline. In all these silicate crystals it can be shown that irradiation with increasing γ-dose there is a dose Dm for which the TL intensity is maximum. Of course, Dm varies depending on the crystal and irradiated crystal with the dose Dm is stable. If one of these crystals is taken and irradiated with doses from low values up to 400-500Gy, a curve of decreasing TL intensity is obtained; such a curve can be used as a calibration curve.

  15. Emergency Victim Care. A Training Manual for Emergency Medical Technicians. Module 12. Water Accidents, Electrical Emergencies, Hazardous Materials and Radiation Accidents. Revised.

    ERIC Educational Resources Information Center

    Ohio State Dept. of Education, Columbus. Div. of Vocational Education.

    This training manual for emergency medical technicians, one of 14 modules that comprise the Emergency Victim Care textbook, covers water accidents, electrical emergencies, and hazardous materials and radiation accidents. Objectives stated for the three chapters are for the students to be able to describe: emergency care for specified water…

  16. The UF family of hybrid phantoms of the developing human fetus for computational radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Maynard, Matthew R.; Geyer, John W.; Aris, John P.; Shifrin, Roger Y.; Bolch, Wesley

    2011-08-01

    Historically, the development of computational phantoms for radiation dosimetry has primarily been directed at capturing and representing adult and pediatric anatomy, with less emphasis devoted to models of the human fetus. As concern grows over possible radiation-induced cancers from medical and non-medical exposures of the pregnant female, the need to better quantify fetal radiation doses, particularly at the organ-level, also increases. Studies such as the European Union's SOLO (Epidemiological Studies of Exposed Southern Urals Populations) hope to improve our understanding of cancer risks following chronic in utero radiation exposure. For projects such as SOLO, currently available fetal anatomic models do not provide sufficient anatomical detail for organ-level dose assessment. To address this need, two fetal hybrid computational phantoms were constructed using high-quality magnetic resonance imaging and computed tomography image sets obtained for two well-preserved fetal specimens aged 11.5 and 21 weeks post-conception. Individual soft tissue organs, bone sites and outer body contours were segmented from these images using 3D-DOCTOR™ and then imported to the 3D modeling software package Rhinoceros™ for further modeling and conversion of soft tissue organs, certain bone sites and outer body contours to deformable non-uniform rational B-spline surfaces. The two specimen-specific phantoms, along with a modified version of the 38 week UF hybrid newborn phantom, comprised a set of base phantoms from which a series of hybrid computational phantoms was derived for fetal ages 8, 10, 15, 20, 25, 30, 35 and 38 weeks post-conception. The methodology used to construct the series of phantoms accounted for the following age-dependent parameters: (1) variations in skeletal size and proportion, (2) bone-dependent variations in relative levels of bone growth, (3) variations in individual organ masses and total fetal masses and (4) statistical percentile variations in

  17. Epid Dosimetry

    SciTech Connect

    Greer, Peter B.; Vial, Philip

    2011-05-05

    Electronic portal imaging devices (EPIDs) were introduced originally for patient position verification. The idea of using EPIDs for dosimetry was realised in the 1980s. Little was published on the topic until the mid 1990's, when the interest in EPIDs for dosimetry increased rapidly and continues to grow. The increasing research on EPID dosimetry coincided with the introduction of intensity modulated radiation therapy (IMRT). EPIDs are well suited to IMRT dosimetry because they are high resolution, two-dimensional (2D) digital detectors. They are also pre-existing on almost all modern linear accelerators. They generally show a linear response to increasing dose. Different types of EPIDs have been clinically implemented, and these have been described in several review papers. The current generation of commercially available EPIDs are indirect detection active matrix flat panel imagers, also known as amorphous silicon (a-Si) EPIDs. Disadvantages of a-Si EPIDs for dosimetry include non-water equivalent construction materials, and the energy sensitivity and optical scatter of the phosphor scintillators used to create optical signal from the megavoltage beam. This report discusses current knowledge regarding a-Si EPIDs for dosimetry.

  18. Epid Dosimetry

    NASA Astrophysics Data System (ADS)

    Greer, Peter B.; Vial, Philip

    2011-05-01

    Electronic portal imaging devices (EPIDs) were introduced originally for patient position verification. The idea of using EPIDs for dosimetry was realised in the 1980s. Little was published on the topic until the mid 1990's, when the interest in EPIDs for dosimetry increased rapidly and continues to grow. The increasing research on EPID dosimetry coincided with the introduction of intensity modulated radiation therapy (IMRT). EPIDs are well suited to IMRT dosimetry because they are high resolution, two-dimensional (2D) digital detectors. They are also pre-existing on almost all modern linear accelerators. They generally show a linear response to increasing dose. Different types of EPIDs have been clinically implemented, and these have been described in several review papers. The current generation of commercially available EPIDs are indirect detection active matrix flat panel imagers, also known as amorphous silicon (a-Si) EPIDs. Disadvantages of a-Si EPIDs for dosimetry include non-water equivalent construction materials, and the energy sensitivity and optical scatter of the phosphor scintillators used to create optical signal from the megavoltage beam. This report discusses current knowledge regarding a-Si EPIDs for dosimetry.

  19. Monitoring of radiation fields in a waste tank model: Virtual radiation dosimetry

    SciTech Connect

    Tulenko, J.S.

    1995-12-31

    The University of Florida (UF) has developed a coupled radiation computation and three-dimensional modeling simulation code package. This package combines the Deneb Robotics` IGRIP three-dimensional solid modeling robotic simulation code with the UF developed VRF (Virtual Radiation Field) Monte Carlo based radiation computation code. The code package allows simulated radiation dose monitors to be placed anywhere on simulated robotic equipment to record the radiation doses which would be sustained when carrying out tasks in radiation environments. Comparison with measured values in the Hanford Waste Tank C-106 shows excellent results. The code shows promise of serving as a major tool in the design and operation of robotic equipment in radiation environments to ensure freedom from radiation caused failure.

  20. The PUR Experiment on the EXPOSE-R facility: biological dosimetry of solar extraterrestrial UV radiation

    NASA Astrophysics Data System (ADS)

    Bérces, A.; Egyeki, M.; Fekete, A.; Horneck, G.; Kovács, G.; Panitz, C.

    2015-01-01

    The aim of our experiment Phage and Uracil Response was to extend the use of bacteriophage T7 and uracil biological dosimeters for measuring the biologically effective ultraviolet (UV) dose in the harsh extraterrestrial radiation conditions. The biological detectors were exposed in vacuum-tightly cases in the European Space Agency (ESA) astrobiological exposure facility attached to the external platform of Zvezda (EXPOSE-R). EXPOSE-R took off to the International Space Station (ISS) in November 2008 and was installed on the External platform of the Russian module Zvezda of the ISS in March 2009. Our goal was to determine the dose-effect relation for the formation of photoproducts (i.e. damage to phage DNA and uracil, respectively). The extraterrestrial solar UV radiation ranges over the whole spectrum from vacuum-UV (λ<200 nm) to UVA (315 nm<λ<400 nm), which causes photolesions (photoproducts) in the nucleic acids/their components either by photoionization or excitation. However, these wavelengths cause not only photolesions but in a wavelength-dependent efficiency the reversion of some photolesions, too. Our biological detectors measured in situ conditions the resultant of both reactions induced by the extraterrestrial UV radiation. From this aspect the role of the photoreversion in the extension of the biological UV dosimetry are discussed.

  1. A wireless transmission low-power radiation sensor for in vivo dosimetry

    NASA Astrophysics Data System (ADS)

    Fuschino, F.; Gabrielli, A.; Baldazzi, G.; Campana, R.; Valentinetti, S.; Crepaldi, M.; Demarchi, D.; Villani, G.

    2014-02-01

    The aim of the paper is to illustrate the design and the performance of a microelectronic circuit composed of a dosimeter, an oscillator, a modulator, a transmitter and an antenna. The device was designed for specific in vivo dosimetry applications. However, the layout area of less than 1 mm2 makes it suitable for a large variety of applications, from spot radiation monitoring systems in medicine to accurate measurements of radiation level in high-energy physics experiments. Moreover, due to its extremely low-power budget, it might be also of interest for space applications. The chip embeds a re-programmable floating-gate transistor configured as a radiation sensor and a read-out circuit. Prototype chips have been fabricated and tested exploiting a commercial 180 nm, four-metal CMOS technology. Characterization tests of the performance of the Ultra-Wide Band transmission are summarized. The dosimeter prototype has an estimated sensitivity of 1 mV/rad within a total absorbed dose range up to 10 krad. The read-out circuit is powered with 3.3 V and the total power consumption is very low, i.e. about 165 μW, making it also upgradable with a remote power system.

  2. Analysis of MIR-18 results for physical and biological dosimetry: radiation shielding effectiveness in LEO.

    PubMed

    Cucinotta, F A; Wilson, J W; Williams, J R; Dicello, J F

    2000-06-01

    We compare models of radiation transport and biological response to physical and biological dosimetry results from astronauts on the Mir space station. Transport models are shown to be in good agreement with physical measurements and indicate that the ratio of equivalent dose from the Galactic Cosmic Rays (GCR) to protons is about 3/2:1 and that this ratio will increase for exposures to internal organs. Two biological response models are used to compare to the Mir biodosimetry for chromosome aberration in lymphocyte cells; a track-structure model and the linear-quadratic model with linear energy transfer (LET) dependent weighting coefficients. These models are fit to in vitro data for aberration formation in human lymphocytes by photons and charged particles. Both models are found to be in reasonable agreement with data for aberrations in lymphocytes of Mir crew members: however there are differences between the use of LET dependent weighting factors and track structure models for assigning radiation quality factors. The major difference in the models is the increased effectiveness predicted by the track model for low charge and energy ions with LET near 10 keV/micrometers. The results of our calculations indicate that aluminum shielding, although providing important mitigation of the effects of trapped radiation, provides no protective effect from the galactic cosmic rays (GCR) in low-earth orbit (LEO) using either equivalent dose or the number of chromosome aberrations as a measure until about 100 g/cm 2 of material is used. PMID:11543368

  3. Workshop Report on Atomic Bomb Dosimetry--Residual Radiation Exposure: Recent Research and Suggestions for Future Studies

    SciTech Connect

    2013-06-06

    There is a need for accurate dosimetry for studies of health effects in the Japanese atomic bomb survivors because of the important role that these studies play in worldwide radiation protection standards. International experts have developed dosimetry systems, such as the Dosimetry System 2002 (DS02), which assess the initial radiation exposure to gamma rays and neutrons but only briefly consider the possibility of some minimal contribution to the total body dose by residual radiation exposure. In recognition of the need for an up-to-date review of the topic of residual radiation exposure in Hiroshima and Nagasaki, recently reported studies were reviewed at a technical session at the 57th Annual Meeting of the Health Physics Society in Sacramento, California, 22-26 July 2012. A one-day workshop was also held to provide time for detailed discussion of these newer studies and to evaluate their potential use in clarifying the residual radiation exposures to the atomic-bomb survivors at Hiroshima and Nagasaki. Suggestions for possible future studies are also included in this workshop report.

  4. Workshop report on atomic bomb dosimetry-residual radiation exposure: recent research and suggestions for future studies.

    PubMed

    Kerr, George D; Egbert, Stephen D; Al-Nabulsi, Isaf; Beck, Harold L; Cullings, Harry M; Endo, Satoru; Hoshi, Masaharu; Imanaka, Tetsuji; Kaul, Dean C; Maruyama, Satoshi; Reeves, Glen I; Ruehm, Werner; Sakaguchi, Aya; Simon, Steven L; Spriggs, Gregory D; Stram, Daniel O; Tonda, Tetsuji; Weiss, Joseph F; Weitz, Ronald L; Young, Robert W

    2013-08-01

    There is a need for accurate dosimetry for studies of health effects in the Japanese atomic bomb survivors because of the important role that these studies play in worldwide radiation protection standards. International experts have developed dosimetry systems, such as the Dosimetry System 2002 (DS02), which assess the initial radiation exposure to gamma rays and neutrons but only briefly consider the possibility of some minimal contribution to the total body dose by residual radiation exposure. In recognition of the need for an up-to-date review of the topic of residual radiation exposure in Hiroshima and Nagasaki, recently reported studies were reviewed at a technical session at the 57th Annual Meeting of the Health Physics Society in Sacramento, California, 22-26 July 2012. A one-day workshop was also held to provide time for detailed discussion of these newer studies and to evaluate their potential use in clarifying the residual radiation exposures to the atomic-bomb survivors at Hiroshima and Nagasaki. Suggestions for possible future studies are also included in this workshop report. PMID:23799498

  5. Workshop report on atomic bomb dosimetry-residual radiation exposure: recent research and suggestions for future studies.

    PubMed

    Kerr, George D; Egbert, Stephen D; Al-Nabulsi, Isaf; Beck, Harold L; Cullings, Harry M; Endo, Satoru; Hoshi, Masaharu; Imanaka, Tetsuji; Kaul, Dean C; Maruyama, Satoshi; Reeves, Glen I; Ruehm, Werner; Sakaguchi, Aya; Simon, Steven L; Spriggs, Gregory D; Stram, Daniel O; Tonda, Tetsuji; Weiss, Joseph F; Weitz, Ronald L; Young, Robert W

    2013-08-01

    There is a need for accurate dosimetry for studies of health effects in the Japanese atomic bomb survivors because of the important role that these studies play in worldwide radiation protection standards. International experts have developed dosimetry systems, such as the Dosimetry System 2002 (DS02), which assess the initial radiation exposure to gamma rays and neutrons but only briefly consider the possibility of some minimal contribution to the total body dose by residual radiation exposure. In recognition of the need for an up-to-date review of the topic of residual radiation exposure in Hiroshima and Nagasaki, recently reported studies were reviewed at a technical session at the 57th Annual Meeting of the Health Physics Society in Sacramento, California, 22-26 July 2012. A one-day workshop was also held to provide time for detailed discussion of these newer studies and to evaluate their potential use in clarifying the residual radiation exposures to the atomic-bomb survivors at Hiroshima and Nagasaki. Suggestions for possible future studies are also included in this workshop report.

  6. A framework for estimating radiation-related cancer risks in Japan from the 2011 Fukushima nuclear accident.

    PubMed

    Walsh, L; Zhang, W; Shore, R E; Auvinen, A; Laurier, D; Wakeford, R; Jacob, P; Gent, N; Anspaugh, L R; Schüz, J; Kesminiene, A; van Deventer, E; Tritscher, A; del Rosarion Pérez, M

    2014-11-01

    We present here a methodology for health risk assessment adopted by the World Health Organization that provides a framework for estimating risks from the Fukushima nuclear accident after the March 11, 2011 Japanese major earthquake and tsunami. Substantial attention has been given to the possible health risks associated with human exposure to radiation from damaged reactors at the Fukushima Daiichi nuclear power station. Cumulative doses were estimated and applied for each post-accident year of life, based on a reference level of exposure during the first year after the earthquake. A lifetime cumulative dose of twice the first year dose was estimated for the primary radionuclide contaminants ((134)Cs and (137)Cs) and are based on Chernobyl data, relative abundances of cesium isotopes, and cleanup efforts. Risks for particularly radiosensitive cancer sites (leukemia, thyroid and breast cancer), as well as the combined risk for all solid cancers were considered. The male and female cumulative risks of cancer incidence attributed to radiation doses from the accident, for those exposed at various ages, were estimated in terms of the lifetime attributable risk (LAR). Calculations of LAR were based on recent Japanese population statistics for cancer incidence and current radiation risk models from the Life Span Study of Japanese A-bomb survivors. Cancer risks over an initial period of 15 years after first exposure were also considered. LAR results were also given as a percentage of the lifetime baseline risk (i.e., the cancer risk in the absence of radiation exposure from the accident). The LAR results were based on either a reference first year dose (10 mGy) or a reference lifetime dose (20 mGy) so that risk assessment may be applied for relocated and non-relocated members of the public, as well as for adult male emergency workers. The results show that the major contribution to LAR from the reference lifetime dose comes from the first year dose. For a dose of 10 mGy in

  7. A framework for estimating radiation-related cancer risks in Japan from the 2011 Fukushima nuclear accident.

    PubMed

    Walsh, L; Zhang, W; Shore, R E; Auvinen, A; Laurier, D; Wakeford, R; Jacob, P; Gent, N; Anspaugh, L R; Schüz, J; Kesminiene, A; van Deventer, E; Tritscher, A; del Rosarion Pérez, M

    2014-11-01

    We present here a methodology for health risk assessment adopted by the World Health Organization that provides a framework for estimating risks from the Fukushima nuclear accident after the March 11, 2011 Japanese major earthquake and tsunami. Substantial attention has been given to the possible health risks associated with human exposure to radiation from damaged reactors at the Fukushima Daiichi nuclear power station. Cumulative doses were estimated and applied for each post-accident year of life, based on a reference level of exposure during the first year after the earthquake. A lifetime cumulative dose of twice the first year dose was estimated for the primary radionuclide contaminants ((134)Cs and (137)Cs) and are based on Chernobyl data, relative abundances of cesium isotopes, and cleanup efforts. Risks for particularly radiosensitive cancer sites (leukemia, thyroid and breast cancer), as well as the combined risk for all solid cancers were considered. The male and female cumulative risks of cancer incidence attributed to radiation doses from the accident, for those exposed at various ages, were estimated in terms of the lifetime attributable risk (LAR). Calculations of LAR were based on recent Japanese population statistics for cancer incidence and current radiation risk models from the Life Span Study of Japanese A-bomb survivors. Cancer risks over an initial period of 15 years after first exposure were also considered. LAR results were also given as a percentage of the lifetime baseline risk (i.e., the cancer risk in the absence of radiation exposure from the accident). The LAR results were based on either a reference first year dose (10 mGy) or a reference lifetime dose (20 mGy) so that risk assessment may be applied for relocated and non-relocated members of the public, as well as for adult male emergency workers. The results show that the major contribution to LAR from the reference lifetime dose comes from the first year dose. For a dose of 10 mGy in

  8. Changes in Occupational Radiation Exposures after Incorporation of a Real-time Dosimetry System in the Interventional Radiology Suite.

    PubMed

    Poudel, Sashi; Weir, Lori; Dowling, Dawn; Medich, David C

    2016-08-01

    A statistical pilot study was retrospectively performed to analyze potential changes in occupational radiation exposures to Interventional Radiology (IR) staff at Lawrence General Hospital after implementation of the i2 Active Radiation Dosimetry System (Unfors RaySafe Inc, 6045 Cochran Road Cleveland, OH 44139-3302). In this study, the monthly OSL dosimetry records obtained during the eight-month period prior to i2 implementation were normalized to the number of procedures performed during each month and statistically compared to the normalized dosimetry records obtained for the 8-mo period after i2 implementation. The resulting statistics included calculation of the mean and standard deviation of the dose equivalences per procedure and included appropriate hypothesis tests to assess for statistically valid differences between the pre and post i2 study periods. Hypothesis testing was performed on three groups of staff present during an IR procedure: The first group included all members of the IR staff, the second group consisted of the IR radiologists, and the third group consisted of the IR technician staff. After implementing the i2 active dosimetry system, participating members of the Lawrence General IR staff had a reduction in the average dose equivalence per procedure of 43.1% ± 16.7% (p = 0.04). Similarly, Lawrence General IR radiologists had a 65.8% ± 33.6% (p=0.01) reduction while the technologists had a 45.0% ± 14.4% (p=0.03) reduction. PMID:27356166

  9. Changes in Occupational Radiation Exposures after Incorporation of a Real-time Dosimetry System in the Interventional Radiology Suite.

    PubMed

    Poudel, Sashi; Weir, Lori; Dowling, Dawn; Medich, David C

    2016-08-01

    A statistical pilot study was retrospectively performed to analyze potential changes in occupational radiation exposures to Interventional Radiology (IR) staff at Lawrence General Hospital after implementation of the i2 Active Radiation Dosimetry System (Unfors RaySafe Inc, 6045 Cochran Road Cleveland, OH 44139-3302). In this study, the monthly OSL dosimetry records obtained during the eight-month period prior to i2 implementation were normalized to the number of procedures performed during each month and statistically compared to the normalized dosimetry records obtained for the 8-mo period after i2 implementation. The resulting statistics included calculation of the mean and standard deviation of the dose equivalences per procedure and included appropriate hypothesis tests to assess for statistically valid differences between the pre and post i2 study periods. Hypothesis testing was performed on three groups of staff present during an IR procedure: The first group included all members of the IR staff, the second group consisted of the IR radiologists, and the third group consisted of the IR technician staff. After implementing the i2 active dosimetry system, participating members of the Lawrence General IR staff had a reduction in the average dose equivalence per procedure of 43.1% ± 16.7% (p = 0.04). Similarly, Lawrence General IR radiologists had a 65.8% ± 33.6% (p=0.01) reduction while the technologists had a 45.0% ± 14.4% (p=0.03) reduction.

  10. Radiation dosimetry of 131I-chlorotoxin for targeted radiotherapy in glioma-bearing mice.

    PubMed

    Shen, Sui; Khazaeli, M B; Gillespie, G Yancey; Alvarez, Vernon L

    2005-01-01

    Chlorotoxin, or TM-601, is a peptide derived from the venom of the scorpionLeiurus Quinquestriatus that specifically binds to malignant brain tumors, but not to normal tissues. Targeted radiotherapy using 131I-Chlorotoxin is promising for post-surgery treatment of brain tumors. This study reports dosimetry results of 131I-Chlorotoxin in athymic nude mice with intracranially implanted human glioma xenografts and projected radiation doses in patients receiving 370 MBq of 131I-Chlorotoxin. 125I/131I-Chlorotoxin were injected into the right brain where D54 MG xenografts were implanted. Mice were sacrificed 24-96 h later. The blood, normal organs, and tumors were weighed and counted to determine 131I-Chlorotoxin concentration. The radiation dose from 131I was calculated based on non-penetrating radiation in the mouse model. Assuming similar tissue uptake in mice and patients, radiation doses for patients were extrapolated. Distributions of 125I/131I-Chlorotoxin were only significant in tumor, stomach, kidneys, and brain (injection site), reflecting non-specific uptake of Chlorotoxin in normal tissues. Mean radiation dose (cGy/37 kBq) was 58.2 for tumor, 17.9 for brains, 1.8 for marrow, 27.1 for stomach, 16.0 for kidneys in mice. For intracranial injection of 370 MBq 131I-Chlorotoxin in patients, extrapolated patient dose (cGy) was 70 for brains, 6 for marrow, 35 for stomach, 60 to kidneys, 227 to tumor, suggesting that 3.7 GBq of 131I-Chlorotoxin can be safely administrated to patients. These promising results demonstrated potential in improving patient survival using this novel targeting agent.

  11. Two-parametric model of electron beam in computational dosimetry for radiation processing

    NASA Astrophysics Data System (ADS)

    Lazurik, V. M.; Lazurik, V. T.; Popov, G.; Zimek, Z.

    2016-07-01

    Computer simulation of irradiation process of various materials with electron beam (EB) can be applied to correct and control the performances of radiation processing installations. Electron beam energy measurements methods are described in the international standards. The obtained results of measurements can be extended by implementation computational dosimetry. Authors have developed the computational method for determination of EB energy on the base of two-parametric fitting of semi-empirical model for the depth dose distribution initiated by mono-energetic electron beam. The analysis of number experiments show that described method can effectively consider random displacements arising from the use of aluminum wedge with a continuous strip of dosimetric film and minimize the magnitude uncertainty value of the electron energy evaluation, calculated from the experimental data. Two-parametric fitting method is proposed for determination of the electron beam model parameters. These model parameters are as follow: E0 - energy mono-energetic and mono-directional electron source, X0 - the thickness of the aluminum layer, located in front of irradiated object. That allows obtain baseline data related to the characteristic of the electron beam, which can be later on applied for computer modeling of the irradiation process. Model parameters which are defined in the international standards (like Ep- the most probably energy and Rp - practical range) can be linked with characteristics of two-parametric model (E0, X0), which allows to simulate the electron irradiation process. The obtained data from semi-empirical model were checked together with the set of experimental results. The proposed two-parametric model for electron beam energy evaluation and estimation of accuracy for computational dosimetry methods on the base of developed model are discussed.

  12. Epid cine acquisition mode for in vivo dosimetry in dynamic arc radiation therapy

    NASA Astrophysics Data System (ADS)

    Fidanzio, Andrea; Mameli, Alessandra; Placidi, Elisa; Greco, Francesca; Stimato, Gerardina; Gaudino, Diego; Ramella, Sara; D'Angelillo, Rolando; Cellini, Francesco; Trodella, Lucio; Cilla, Savino; Grimaldi, Luca; D'Onofrio, Guido; Azario, Luigi; Piermattei, Angelo

    2008-02-01

    In this paper the cine acquisition mode of an electronic portal imaging device (EPID) has been calibrated and tested to determine the in vivo dose for dynamic conformal arc radiation therapy (DCAT). The EPID cine acquisition mode, that allows a frame acquisition rate of one image every 1.66 s, was studied with a monitor unit rate equal to 100 UM/min. In these conditions good signal stability, ±1% (2SD) evaluated during three months, signal reproducibility within ±0.8% (2SD) and linearity with dose and dose rate within ±1% (2SD) were obtained. The transit signal, St, (due to the transmitted beam below the phantom) measured by the EPID cine acquisition mode was used to determine, (i) a set of correlation functions, F(w,L), defined as the ratio between St and the dose at half thickness, Dm, measured in solid water phantoms of different thicknesses, w and with square fields of side L, (ii) a set of factors, f(d,L), that take into account the different X-ray scatter contribution from the phantom to the St signal as a function of the variation, d, of the air gap between the phantom and the EPID. The reconstruction of the isocenter dose, Diso, for DCAT was obtained convolving the transit signal values, obtained at different gantry angles, with the respective reconstruction factors determined by a house-made software. The method was tested with cylindrical and anthropomorphic phantoms and the results show that the reconstructed Diso values can be obtained with an accuracy within ±2.5% in cylindrical phantom and within ±3.4% for anthropomorphic phantom. In conclusion, the transit dosimetry by EPID was assessed to be adequate to perform DCAT in vivo dosimetry, that is not realizable with the other traditional techniques. Moreover, the method proposed here could be implemented to supply in vivo dose values in real time.

  13. Accurate patient dosimetry of kilovoltage cone-beam CT in radiation therapy

    SciTech Connect

    Ding, George X.; Duggan, Dennis M.; Coffey, Charles W.

    2008-03-15

    The increased utilization of x-ray imaging in image-guided radiotherapy has dramatically improved the radiation treatment and the lives of cancer patients. Daily imaging procedures, such as cone-beam computed tomography (CBCT), for patient setup may significantly increase the dose to the patient's normal tissues. This study investigates the dosimetry from a kilovoltage (kV) CBCT for real patient geometries. Monte Carlo simulations were used to study the kV beams from a Varian on-board imager integrated into the Trilogy accelerator. The Monte Carlo calculated results were benchmarked against measurements and good agreement was obtained. The authors developed a novel method to calibrate Monte Carlo simulated beams with measurements using an ionization chamber in which the air-kerma calibration factors are obtained from an Accredited Dosimetry Calibration Laboratory. The authors have introduced a new Monte Carlo calibration factor, f{sub MCcal}, which is determined from the calibration procedure. The accuracy of the new method was validated by experiment. When a Monte Carlo simulated beam has been calibrated, the simulated beam can be used to accurately predict absolute dose distributions in the irradiated media. Using this method the authors calculated dose distributions to patient anatomies from a typical CBCT acquisition for different treatment sites, such as head and neck, lung, and pelvis. Their results have shown that, from a typical head and neck CBCT, doses to soft tissues, such as eye, spinal cord, and brain can be up to 8, 6, and 5 cGy, respectively. The dose to the bone, due to the photoelectric effect, can be as much as 25 cGy, about three times the dose to the soft tissue. The study provides detailed information on the additional doses to the normal tissues of a patient from a typical kV CBCT acquisition. The methodology of the Monte Carlo beam calibration developed and introduced in this study allows the user to calculate both relative and absolute

  14. Investigation of thermal and temporal responses of ionization chambers in radiation dosimetry.

    PubMed

    AlMasri, Hussein; Funyu, Akira; Kakinohana, Yasumasa; Murayama, Sadayuki

    2012-07-01

    The ionization chamber is a primary dosimeter that is used in radiation dosimetry. Generally, the ion chamber response requires temperature/pressure correction according to the ideal gas law. However, this correction does not consider the thermal volume effect of chambers. The temporal and thermal volume effects of various chambers (CC01, CC13, NACP parallel-plate, PTW) with different wall and electrode materials have been studied in a water phantom. Measurements were done after heating the water with a suitable heating system, and chambers were submerged for a sufficient time to allow for temperature equilibrium. Temporal results show that all chambers equilibrate quickly in water. The equilibration time was between 3 and 5 min for all chambers. Thermal results show that all chambers expanded in response to heating except for the PTW, which contracted. This might be explained by the differences in the volumes of all chambers and also by the difference in wall material composition of PTW from the other chambers. It was found that the smallest chamber, CC01, showed the greatest expansion. The magnitude of the expansion was ~1, 0.8, and 0.9% for CC01, CC13, and parallel-plate chambers, respectively, in the temperature range of 295-320 K. The magnitude of the detected contraction was <0.3% for PTW in the same temperature range. For absolute dosimetry, it is necessary to make corrections for the ion chamber response, especially for small ion chambers like the CC01. Otherwise, room and water phantom temperatures should remain within a close range. PMID:22467281

  15. EBT GAFCHROMIC{sup TM} film dosimetry in compensator-based intensity modulated radiation therapy

    SciTech Connect

    Vaezzadeh, Seyedali; Allahverdi, Mahmoud; Nedaie, Hasan A.; Ay, Mohammadreza; Shirazi, Alireza; Yarahmadi, Mehran

    2013-07-01

    The electron benefit transfer (EBT) GAFCHROMIC films possess a number of features making them appropriate for high-quality dosimetry in intensity-modulated radiation therapy (IMRT). Compensators to deliver IMRT are known to change the beam-energy spectrum as well as to produce scattered photons and to contaminate electrons; therefore, the accuracy and validity of EBT-film dosimetry in compensator-based IMRT should be investigated. Percentage-depth doses and lateral-beam profiles were measured using EBT films in perpendicular orientation with respect to 6 and 18 MV photon beam energies for: (1) different thicknesses of cerrobend slab (open, 1.0, 2.0, 4.0, and 6.0 cm), field sizes (5×5, 10×10, and 20×20 cm{sup 2}), and measurement depths (D{sub max}, 5.0 and 10.0 cm); and (2) step-wedged compensator in a solid phantom. To verify results, same measurements were implemented using a 0.125 cm{sup 3} ionization chamber in a water phantom and also in Monte Carlo simulations using the Monte Carlo N-particle radiation transport computer code. The mean energy of photons was increased due to beam hardening in comparison with open fields at both 6 and 18 MV energies. For a 20×20 cm{sup 2} field size of a 6 MV photon beam and a 6.0 cm thick block, the surface dose decreased by about 12% and percentage-depth doses increased up to 3% at 30.0 cm depth, due to the beam-hardening effect induced by the block. In contrast, at 18 MV, the surface dose increased by about 8% and depth dose reduced by 3% at 30.0 cm depth. The penumbral widths (80% to 20%) increase with block thickness, field size, and beam energy. The EBT film results were in good agreement with the ionization chamber dose profiles and Monte Carlo N-particle radiation transport computer code simulation behind the step-wedged compensator. Also, there was a good agreement between the EBT-film and the treatment-planning results on the anthropomorphic phantom. The EBT films can be accurately used as a 2D dosimeter for dose

  16. Application of radiation physics to improve dosimetry in early breast cancer radiotherapy

    SciTech Connect

    Donovan, Ellen Mary

    2005-07-15

    Radiotherapy for early breast cancer has been shown to be a highly effective treatment in a number of long term studies. The radiation dose uniformity of the current standard treatments is often poor, however, with dose variations across the breast much higher than those recommended in international guidelines. This work aimed to explore methods for improving this aspect of the radiation dosimetry of early breast cancer radiotherapy. An experimental method was validated by applying it to computed tomography data from 14 patients with a variety of breast shapes and sizes. The volume of the breast receiving the desired dose levels increased by a mean of 6.9% (range -0.8% to 15.9%) and this benefit was shown to increase with breast volume. The quality of reference images in the verification of treatments was improved by introducing differential filtering to the imaging beams on a radiotherapy simulator. The positive results from the first two studies were applied in a clinical trial (which used the experimental technique). The unique set of data from the trial was analyzed and confirmation of dosimetric improvement, and the increased benefit, for larger breasted women were found. In addition, an analysis of the position of high doses showed these occurred in the upper or lower third of the breast and affected 46% and 30% of patients, respectively, with standard treatment but only 1% of patients with the improved method. Other published methods for improving breast dosimetry were explored by building a simple physical model and carrying out a comparative planning study. The physical model was shown to be effective in predicting the dosimetric consequences of each method. The planning study showed that there was little difference between the methods generally but dosimetric improvement could be increased for larger breast volumes by an appropriate choice of technique. A final study explored how breathing control could be used to reduce cardiac doses in patients with

  17. Optical and NMR dose response of N-isopropylacrylamide normoxic polymer gel for radiation therapy dosimetry

    PubMed Central

    Mesbahi, Asghar; Jafarzadeh, Vahid; Gharehaghaji, Nahideh

    2012-01-01

    Background Application of less toxic normoxic polymer gel of N-isopropyl acrylamide (NIPAM) for radiation therapy has been studied in recent years. Aim In the current study the optical and NMR properties of NIPAM were studied for radiation therapy dosimetry application. Materials and methods NIPAM normoxic polymer gel was prepared and irradiated by 9 MV photon beam of a medical linac. The optical absorbance was measured using a conventional laboratory spectrophotometer in different wavelengths ranging from 390 to 860 nm. R2 measurements of NIPAM gels were performed using a 1.5 T scanner and R2–dose curve was obtained. Results Our results showed R2 dose sensitivity of 0.193 ± 0.01 s−1 Gy−1 for NIPAM gel. Both R2 and optical absorbance showed a linear relationship with dose from 1.5 to 11 Gy for NIPAM gel dosimeter. Moreover, absorbance–dose response varied considerably with light wavelength and highest sensitivity was seen for the blue part of the spectrum. Conclusion Our results showed that both optical and NMR approaches have acceptable sensitivity and accuracy for dose determination with NIPAM gel. However, for optical reading of the gel, utilization of an optimum optical wavelength is recommended. PMID:24377016

  18. Intercomparison of luminescence detectors for space radiation dosimetry within Proton-ICCHIBAN experiments

    NASA Astrophysics Data System (ADS)

    Uchihori, Yukio; Ploc, Ondrej; Yasuda, Nakahiro; Berger, Thomas; Hajek, Michael; Kodaira, Satoshi; Benton, Eric; Ambrozova, Iva; Kitamura, Hisashi

    2012-07-01

    Luminescence detectors for space radiation dosimetry are frequently used to estimate personal and environmental doses in the International Space Station and other space vehicles. Detector responses for cosmic rays and their secondaries were investigated for a long time and it is well-known that luminescence detectors have dependencies of response on LET (Linear Energy Transfer). Some of luminescence detectors show over-response to gamma rays (used for routine calibration) and others have similar responses to gamma rays. But, because of lack of sufficient and reliable calibration data in the low LET region (about 1 keV/μm), it is the responses of these detectors at LET is poorly known. Protons make up the dominant portion of the fluence from space radiation, so the LET region corresponding to energetic protons must be characterized very well. For that purpose, calibration and intercomparison experiments were performed using relatively low energy (30 to 80 MeV) proton beams at the National Institute of Radiological Sciences, Chiba, Japan. In this paper, the results of these intercomparison experiments, including high energy protons and light ions, are reported and illustrate the response of luminescence detectors in the low LET region. This research will help improve our understanding of space dosimeters and reliable dose measurement for astronauts and cosmonauts in low earth orbit.

  19. The Impact of Iterative Reconstruction on Computed Tomography Radiation Dosimetry: Evaluation in a Routine Clinical Setting

    PubMed Central

    Moorin, Rachael E.; Gibson, David A. J.; Forsyth, Rene K.; Fox, Richard

    2015-01-01

    Purpose To evaluate the effect of introduction of iterative reconstruction as a mandated software upgrade on radiation dosimetry in routine clinical practice over a range of computed tomography examinations. Methods Random samples of scanning data were extracted from a centralised Picture Archiving Communication System pertaining to 10 commonly performed computed tomography examination types undertaken at two hospitals in Western Australia, before and after the introduction of iterative reconstruction. Changes in the mean dose length product and effective dose were evaluated along with estimations of associated changes to annual cancer incidence. Results We observed statistically significant reductions in the effective radiation dose for head computed tomography (22–27%) consistent with those reported in the literature. In contrast the reductions observed for non-contrast chest (37–47%); chest pulmonary embolism study (28%), chest/abdominal/pelvic study (16%) and thoracic spine (39%) computed tomography. Statistically significant reductions in radiation dose were not identified in angiographic computed tomography. Dose reductions translated to substantial lowering of the lifetime attributable risk, especially for younger females, and estimated numbers of incident cancers. Conclusion Reduction of CT dose is a priority Iterative reconstruction algorithms have the potential to significantly assist with dose reduction across a range of protocols. However, this reduction in dose is achieved via reductions in image noise. Fully realising the potential dose reduction of iterative reconstruction requires the adjustment of image factors and forgoing the noise reduction potential of the iterative algorithm. Our study has demonstrated a reduction in radiation dose for some scanning protocols, but not to the extent experimental studies had previously shown or in all protocols expected, raising questions about the extent to which iterative reconstruction achieves dose

  20. Immediate medical consequences of nuclear accidents: lessons from Chernobyl

    SciTech Connect

    Gale, R.P.

    1987-08-07

    The immediate medical response to the nuclear accident at the Chernobyl nuclear power station involved containment of the radioactivity and evacuation of the nearby population. The next step consisted of assessment of the radiation dose received by individuals, based on biological dosimetry, and treatment of those exposed. Medical care involved treatment of skin burns; measures to support bone marrow failure, gastrointestinal tract injury, and other organ damage (i.e., infection prophylaxis and transfusions) for those with lower radiation dose exposure; and bone marrow transplantation for those exposed to a high dose of radiation. At Chernobyl, two victims died immediately and 29 died of radiation or thermal injuries in the next three months. The remaining victims of the accident are currently well. A nuclear accident anywhere is a nuclear accident everywhere. Prevention and cooperation in response to these accidents are essential goals.

  1. The Australian radiation protection and nuclear safety agency megavoltage photon thermoluminescence dosimetry postal audit service 2007-2010.

    PubMed

    Oliver, C P; Butler, D J; Webb, D V

    2012-03-01

    The Australian radiation protection and nuclear safety agency (ARPANSA) has continuously provided a level 1 mailed thermoluminescence dosimetry audit service for megavoltage photons since 2007. The purpose of the audit is to provide an independent verification of the reference dose output of a radiotherapy linear accelerator in a clinical environment. Photon beam quality measurements can also be made as part of the audit in addition to the output measurements. The results of all audits performed between 2007 and 2010 are presented. The average of all reference beam output measurements calculated as a clinically stated dose divided by an ARPANSA measured dose is 0.9993. The results of all beam quality measurements calculated as a clinically stated quality divided by an ARPANSA measured quality is 1.0087. Since 2011 the provision of all auditing services has been transferred from the Ionizing Radiation Standards section to the Australian Clinical Dosimetry Service (ACDS) which is currently housed within ARPANSA. PMID:22302465

  2. The Australian radiation protection and nuclear safety agency megavoltage photon thermoluminescence dosimetry postal audit service 2007-2010.

    PubMed

    Oliver, C P; Butler, D J; Webb, D V

    2012-03-01

    The Australian radiation protection and nuclear safety agency (ARPANSA) has continuously provided a level 1 mailed thermoluminescence dosimetry audit service for megavoltage photons since 2007. The purpose of the audit is to provide an independent verification of the reference dose output of a radiotherapy linear accelerator in a clinical environment. Photon beam quality measurements can also be made as part of the audit in addition to the output measurements. The results of all audits performed between 2007 and 2010 are presented. The average of all reference beam output measurements calculated as a clinically stated dose divided by an ARPANSA measured dose is 0.9993. The results of all beam quality measurements calculated as a clinically stated quality divided by an ARPANSA measured quality is 1.0087. Since 2011 the provision of all auditing services has been transferred from the Ionizing Radiation Standards section to the Australian Clinical Dosimetry Service (ACDS) which is currently housed within ARPANSA.

  3. Planning on a regional basis for a major radiation accident

    SciTech Connect

    Casey, W.R.

    1981-01-01

    As a part of the Radiological Assistance Program, members of the Safety and Environmental Protection Division of Brookhaven National Laboratory have served as a response team for many years to the northeastern section of the United States. During this time, responses have been made to several significant incidents, including the accident at Three Mile Island. The planning and preparation for emergency response activities will be discussed. Included will be a review of instrument requirements, analytical and support equipment, modes of response, and communication needs. Interaction with and support from other response teams will be discussed. In particular, the lessons from the respone to Three Mile Island will be reviewed.

  4. Dosimetry for quantitative analysis of the effects of low-dose ionizing radiation in radiation therapy patients.

    PubMed

    Lehmann, Joerg; Stern, Robin L; Daly, Thomas P; Rocke, David M; Schwietert, Chad W; Jones, Gregory E; Arnold, Michelle L; Siantar, Christine L Hartmann; Goldberg, Zelanna

    2006-02-01

    We have developed and validated a practical approach to identifying the location on the skin surface that will receive a prespecified biopsy dose (ranging down to 1 cGy) in support of in vivo biological dosimetry in humans. This represents a significant technical challenge since the sites lie on the patient's surface outside the radiation fields. The PEREGRINE Monte Carlo simulation system was used to model radiation dose delivery, and TLDs were used for validation on phantoms and for confirmation during patient treatment. In the developmental studies, the Monte Carlo simulations consistently underestimated the dose at the biopsy site by approximately 15% (of the local dose) for a realistic treatment configuration, most likely due to lack of detail in the simulation of the linear accelerator outside the main beam line. Using a single, thickness-independent correction factor for the clinical calculations, the average of 36 measurements for the predicted 1-cGy point was 0.985 cGy (standard deviation: 0.110 cGy) despite patient breathing motion and other real-world challenges. Since the 10-cGy point is situated in the region of high-dose gradient at the edge of the field, patient motion had a greater effect, and the six measured points averaged 5.90 cGy (standard deviation: 1.01 cGy), a difference that is equivalent to approximately a 6-mm shift on the patient's surface. PMID:16435922

  5. Three Mile Island epidemiologic radiation dose assessment revisited: 25 years after the accident.

    PubMed

    Field, R William

    2005-01-01

    Over the past 25 years, public health concerns following the Three Mile Island (TMI) accident prompted several epidemiologic investigations in the vicinity of TMI. One of these studies is ongoing. This commentary suggests that the major source of radiation exposure to the population has been ignored as a potential confounding factor or effect modifying factor in previous and ongoing TMI epidemiologic studies that explore whether or not TMI accidental plant radiation releases caused an increase in lung cancer in the community around TMI. The commentary also documents the observation that the counties around TMI have the highest regional radon potential in the United States and concludes that radon progeny exposure should be included as part of the overall radiation dose assessment in future studies of radiation-induced lung cancer resulting from the TMI accident. PMID:15657112

  6. Dosimetry of x-ray beams: The measure of the problem

    SciTech Connect

    de Castro, T.M.

    1986-08-01

    This document contains the text of an oral presentation on dosimetry of analytical x-ray equipment presented at the Denver X-Ray Conference. Included are discussions of sources of background radiation, exposure limits from occupational sources, and the relationship of these sources to the high dose source of x-rays found in analytical machines. The mathematical basis of x-ray dosimetry is reviewed in preparation for more detailed notes on personnel dosimetry and the selection of the most appropriate dosimeter for a specific application. The presentation concludes with a discussion common to previous x-ray equipment accidents. 2 refs. (TEM)

  7. [Analysis of radiation-hygienic and medical consequences of the Chernobyl accident].

    PubMed

    Onishchenko, G G

    2013-01-01

    Since the day of "the Chernobyl accident" in 1986 more than 25 years have been past. Radioactively contaminated areas 14 subjects of the Russian Federation with a total area of more than 50 thousand km2, where 1.5 million people now reside were exposed to radioactive contamination. Currently, a system of comprehensive evaluation of radiation doses of the population affected by the "Chernobyl accidents", including 11 guidance documents has been created. There are methodically provided works on the assessment of average annual, accumulated and predicted radiation doses of population and its critical groups, as well as doses to the thyroid gland The relevance of the analysis of the consequences of the "Chernobyl accident" is demonstrated by the events in Japan, at nuclear power Fukusima-1. In 2011 - 20/2 there were carried out comprehensive maritime expeditions under the auspices of the Russian Geographical Society with the participation of relevant ministries and agencies, leading academic institutions in Russia. In 2012, work was carried out on radiation protection of the population from the potential transboundary impact of the accident at the Japanese nuclear power plant Fukushima-l. The results provide a basis for the favorable outlook for the radiation environment in our Far East and the Pacific coast of Russia.

  8. Background radiation and individual dosimetry in the costal area of Tamil Nadu, India.

    PubMed

    Matsuda, Naoki; Brahmanandhan, G M; Yoshida, Masahiro; Takamura, Noboru; Suyama, Akihiko; Koguchi, Yasuhiro; Juto, Norimichi; Raj, Y Lenin; Winsley, Godwin; Selvasekarapandian, S

    2011-07-01

    South coast of India is known as the high-level background radiation area (HBRA) mainly due to beach sands that contain natural radionuclides as components of the mineral monazite. The rich deposit of monazite is unevenly distributed along the coastal belt of Tamil Nadu and Kerala. An HBRA site that laid in 2×7 m along the sea was found in the beach of Chinnavillai, Tamil Nadu, where the maximum ambient dose equivalent reached as high as 162.7 mSv y(-1). From the sands collected at the HBRA spot, the high-purity germanium semi-conductor detector identified six nuclides of thorium series, four nuclides of uranium series and two nuclides belonging to actinium series. The highest radioactivity observed was 43.7 Bq g(-1) of Th-228. The individual dose of five inhabitants in Chinnavillai, as measured by the radiophotoluminescence glass dosimetry system, demonstrated the average dose of 7.17 mSv y(-1) ranging from 2.79 to 14.17 mSv y(-1).

  9. On application of low doses from beta radiation source in OSL retrospective dosimetry

    NASA Astrophysics Data System (ADS)

    Przegietka, K.; Chruscinska, A.

    2014-11-01

    The paper reports on three levels of dose rates obtainable from single beta source: (133±3) mGy/s, (17.8±0.3) mGy/s and (1.94±0.04) mGy/s, as calibrated for quartz sand grains. These values were achieved for different attenuation stages of beta radiation emitted by standard 90Sr/90Y source with the nominal activity of 1.48 GBq attached to an automatic luminescence reader. Lower dose rates give opportunity for exact dosing, which is especially required in luminescence dating applied to young samples as well as in environmental dosimetry. Moreover new method for determining time lag in opening the source in the Riso beta irradiator is presented. This allowed to resolve the contradiction appearing in the literature. The time delay was found to be (0.15±0.01) s per single irradiation. For improving accuracy the dose rate correction is suggest to be taken into account for irradiations shorter than 30 s.

  10. Highly sensitive Europium doped SrSO4 OSL nanophosphor for radiation dosimetry applications

    NASA Astrophysics Data System (ADS)

    Patle, Anita; Patil, R. R.; Kulkarni, M. S.; Bhatt, B. C.; Moharil, S. V.

    2015-10-01

    Highly sensitive Europium doped SrSO4 optically stimulated luminescent (OSL) phosphor was developed by synthesizing a nano phosphor which is treated at 1000 °C. Excellent OSL properties are observed in the developed phosphor and the sensitivity is found to be 1.26 times to that of the commercial Al2O3:C (Landauer Inc.) phosphor based on area integration method. The sample showed a single TL glow peak around 230 °C which is found to reduce by 47% after the OSL readout. Sublinear dose response with the saturation around 100 mGy is observed in this sample which suggests that it is extremely sensitive and hence will be suitable in detecting very low dose levels. Minimum measurable dose on the used set up is estimated to be 1.42 μGy. Practically no fading is observed for first ten days and the phosphor has excellent reusability. High sensitivity, low fading, excellent reusability will make this phosphor suitable for radiation dosimetry applications using OSL.

  11. Background radiation and individual dosimetry in the costal area of Tamil Nadu, India.

    PubMed

    Matsuda, Naoki; Brahmanandhan, G M; Yoshida, Masahiro; Takamura, Noboru; Suyama, Akihiko; Koguchi, Yasuhiro; Juto, Norimichi; Raj, Y Lenin; Winsley, Godwin; Selvasekarapandian, S

    2011-07-01

    South coast of India is known as the high-level background radiation area (HBRA) mainly due to beach sands that contain natural radionuclides as components of the mineral monazite. The rich deposit of monazite is unevenly distributed along the coastal belt of Tamil Nadu and Kerala. An HBRA site that laid in 2×7 m along the sea was found in the beach of Chinnavillai, Tamil Nadu, where the maximum ambient dose equivalent reached as high as 162.7 mSv y(-1). From the sands collected at the HBRA spot, the high-purity germanium semi-conductor detector identified six nuclides of thorium series, four nuclides of uranium series and two nuclides belonging to actinium series. The highest radioactivity observed was 43.7 Bq g(-1) of Th-228. The individual dose of five inhabitants in Chinnavillai, as measured by the radiophotoluminescence glass dosimetry system, demonstrated the average dose of 7.17 mSv y(-1) ranging from 2.79 to 14.17 mSv y(-1). PMID:21502300

  12. (Biological dosimetry)

    SciTech Connect

    Preston, R.J.

    1990-12-17

    The traveler attended the 1st International Conference on Biological Dosimetry in Madrid, Spain. This conference was organized to provide information to a general audience of biologists, physicists, radiotherapists, industrial hygiene personnel and individuals from related fields on the current ability of cytogenetic analysis to provide estimates of radiation dose in cases of occupational or environmental exposure. There is a growing interest in Spain in biological dosimetry because of the increased use of radiation sources for medical and occupational uses, and with this the anticipated and actual increase in numbers of overexposure. The traveler delivered the introductory lecture on Biological Dosimetry: Mechanistic Concepts'' that was intended to provide a framework by which the more applied lectures could be interpreted in a mechanistic way. A second component of the trip was to provide advice with regard to several recent cases of overexposure that had been or were being assessed by the Radiopathology and Radiotherapy Department of the Hospital General Gregorio Maranon'' in Madrid. The traveler had provided information on several of these, and had analyzed cells from some exposed or purportedly exposed individuals. The members of the biological dosimetry group were referred to individuals at REACTS at Oak Ridge Associated Universities for advice on follow-up treatment.

  13. An investigation of PRESAGE® 3D dosimetry for IMRT and VMAT radiation therapy treatment verification

    NASA Astrophysics Data System (ADS)

    Jackson, Jake; Juang, Titania; Adamovics, John; Oldham, Mark

    2015-03-01

    The purpose of this work was to characterize three formulations of PRESAGE® dosimeters (DEA-1, DEA-2, and DX) and to identify optimal readout timing and procedures for accurate in-house 3D dosimetry. The optimal formulation and procedure was then applied for the verification of an intensity modulated radiation therapy (IMRT) and a volumetric modulated arc therapy (VMAT) treatment technique. PRESAGE® formulations were studied for their temporal stability post-irradiation, sensitivity, and linearity of dose response. Dosimeters were read out using a high-resolution optical-CT scanner. Small volumes of PRESAGE® were irradiated to investigate possible differences in sensitivity for large and small volumes (‘volume effect’). The optimal formulation and read-out technique was applied to the verification of two patient treatments: an IMRT plan and a VMAT plan. A gradual decrease in post-irradiation optical-density was observed in all formulations with DEA-1 exhibiting the best temporal stability with less than 4% variation between 2-22 h post-irradiation. A linear dose response at the 4 h time point was observed for all formulations with an R2 value >0.99. A large volume effect was observed for DEA-1 with sensitivity of the large dosimeter being ~63% less than the sensitivity of the cuvettes. For the IMRT and VMAT treatments, the 3D gamma passing rates for 3%/3 mm criteria using absolute measured dose were 99.6 and 94.5% for the IMRT and VMAT treatments, respectively. In summary, this work shows that accurate 3D dosimetry is possible with all three PRESAGE® formulations. The optimal imaging windows post-irradiation were 3-24 h, 2-6 h, and immediately for the DEA-1, DEA-2, and DX formulations, respectively. Because of the large volume effect, small volume cuvettes are not yet a reliable method for calibration of larger dosimeters to absolute dose. Finally, PRESAGE® is observed to be a useful method of 3D verification when careful consideration is given

  14. An investigation of PRESAGE® 3D dosimetry for IMRT and VMAT radiation therapy treatment verification

    PubMed Central

    Jackson, Jake; Juang, Titania; Adamovics, John; Oldham, Mark

    2016-01-01

    The purpose of this work was to characterize three formulations of PRESAGE® dosimeters (DEA-1, DEA-2, and DX) and to identify optimal readout timing and procedures for accurate in-house 3D dosimetry. The optimal formulation and procedure was then applied for the verification of an intensity modulated radiation therapy (IMRT) and a volumetric modulated arc therapy (VMAT) treatment technique. PRESAGE® formulations were studied for their temporal stability postirradiation, sensitivity, and linearity of dose response. Dosimeters were read out using a high-resolution optical-CT scanner. Small volumes of PRESAGE® were irradiated to investigate possible differences in sensitivity for large and small volumes (‘volume effect’). The optimal formulation and read-out technique was applied to the verification of two patient treatments: an IMRT plan and a VMAT plan. A gradual decrease in post-irradiation optical-density was observed in all formulations with DEA-1 exhibiting the best temporal stability with less than 4% variation between 2–22 h post-irradiation. A linear dose response at the 4 h time point was observed for all formulations with an R2 value >0.99. A large volume effect was observed for DEA-1 with sensitivity of the large dosimeter being ~63% less than the sensitivity of the cuvettes. For the IMRT and VMAT treatments, the 3D gamma passing rates for 3%/3 mm criteria using absolute measured dose were 99.6 and 94.5% for the IMRT and VMAT treatments, respectively. In summary, this work shows that accurate 3D dosimetry is possible with all three PRESAGE® formulations. The optimal imaging windows post-irradiation were 3–24 h, 2–6 h, and immediately for the DEA-1, DEA-2, and DX formulations, respectively. Because of the large volume effect, small volume cuvettes are not yet a reliable method for calibration of larger dosimeters to absolute dose. Finally, PRESAGE® is observed to be a useful method of 3D verification when careful consideration is given to the

  15. Panasonic dosimetry system performance testing and results at nuclear accident dose levels 500 rad to 10,000 rad

    SciTech Connect

    Klueber, M.R.

    1998-04-06

    Panasonic thermoluminescent dosimeters (TLDs) are used as the photon dose assessment part of the personal nuclear accident dosimeter (PNAD) and may be used for the same purpose with the fixed nuclear accident dosimeter (FNAD). To demonstrate compliance with 10CFR835.1304 (and, its predecessor, DOE Order 5480.11), several sets of dosimeters were irradiated to photon doses above the upper limit of the DOELAP testing standard, DOE/EH-0026 and DOE/EH-0027. The upper range of the test was 10,000 rads, using both low energy (70 keV) and high energy (662 keV and 1,332 keV) sources. The testing indicated that the Panasonic TLD system is capable of meeting the requirements of 10CFR835.1304 and DOE Order 5480.11.

  16. Uptake of Tl-201 in the testes: Implications for radiation dosimetry

    SciTech Connect

    Stabin, M.G.; Thomas, S.R.; Wilson, R.A.

    1995-05-01

    The radiation dose to the testes from Tl-201 chloride has been an outstanding question for a number of years. Previous studies have presented kinetic data for the testes with percentage uptake ranging over nearly an order of magnitude from 0.15% to 1.2%. Gupta et al. studied the uptake of Tl-201 in testes and reported an uptake of 0.9-1.2%, with no clearance to 24 hours. Use of the value reported by Gupta et al. results in an estimated dose to the testes in the adult of 0.82 mGy/MBq, and causes the testes to be identified as the highest dose organ. In our crossover study we evaluated Tl-201 uptake in the testes of 28 patients who received Tl-201 chloride plus D-Ribose, an experimental clearance agent, and Tl-201 chloride plus a placebo 7 to 14 days later. Quantitative measurements were made under a scintillation camera imaging protocol (following exercise and administration of D-Ribose or the placebo) at approximately 1.5, 4.5, 8, 24, and 48 hr, and 7 to 14 days post injection, during which the isolated testes were shielded from the body background. Images were acquired for 5 minutes at early times and 10 to 15 minutes at the latest time. The data were fit to a two component exponential curve. Uptake and clearance parameters were not significantly different between the two regimens. Mean uptake was 0.31 {plus_minus} 0.11%; the mean residence time in the testes was 0.26 {plus_minus}0.08 hr. The testes dose using this new residence time is about 0.20 mGy/MBq. This estimate should form the basis for testicular radiation dosimetry of Tl-201 chloride.

  17. Digital holographic interferometry: A novel optical calorimetry technique for radiation dosimetry

    SciTech Connect

    Cavan, Alicia; Meyer, Juergen

    2014-02-15

    Purpose: To develop and demonstrate the proof-of-principle of a novel optical calorimetry method to determine radiation absorbed dose in a transparent medium. Methods: The calorimetric property of water is measured during irradiation by means of an interferometer, which detects temperature-induced changes in the refractive index that can be mathematically related to absorbed dose. The proposed method uses a technique called digital holographic interferometry (DHI), which comprises an optical laser interferometer setup and consecutive physical reconstruction of the recorded wave fronts by means of the Fresnel transform. This paper describes the conceptual framework and provides the mathematical basis for DHI dosimetry. Dose distributions from a high dose rate Brachytherapy source were measured by a prototype optical setup to demonstrate the feasibility of the approach. Results: The developed DHI dosimeter successfully determined absorbed dose distributions in water in the region adjacent to a high dose rate Brachytherapy source. A temperature change of 0.0381 K across a distance of 6.8 mm near the source was measured, corresponding to a dose of 159.3 Gy. The standard deviation in a typical measurement set was ±3.45 Gy (corresponding to an uncertainty in the temperature value of ±8.3 × 10{sup −4} K). The relative dose fall off was in agreement with treatment planning system modeled data. Conclusions: First results with a prototype optical setup and a Brachytherapy source demonstrate the proof-of-principle of the approach. The prototype achieves high spatial resolution of approximately 3 × 10{sup −5} m. The general approach is fundamentally independent of the radiation type and energy. The sensitivity range determined indicates that the method is predominantly suitable for high dose rate applications. Further work is required to determine absolute dose in all three dimensions.

  18. Cobalt-60 simulation of LOCA (loss of coolant accident) radiation effects

    SciTech Connect

    Buckalew, W.H.

    1989-07-01

    The consequences of simulating nuclear reactor loss of coolant accident (LOCA) radiation effects with Cobalt-60 gamma ray irradiators have been investigated. Based on radiation induced damage in polymer base materials, it was demonstrated that electron/photon induced radiation damage could be related on the basis of average absorbed radiation dose. This result was used to estimate the relative effectiveness of the mixed beta/gamma LOCA and Cobalt-60 radiation environments to damage both bare and jacketed polymer base electrical insulation materials. From the results obtained, it is concluded that present simulation techniques are a conservative method for simulating LOCA radiation effects and that the practices have probably substantially overstressed both bare and jacketed materials during qualification testing. 9 refs., 8 figs., 5 tabs.

  19. NASA astronaut dosimetry: Implementation of scalable human phantoms and benchmark comparisons of deterministic versus Monte Carlo radiation transport

    NASA Astrophysics Data System (ADS)

    Bahadori, Amir Alexander

    Astronauts are exposed to a unique radiation environment in space. United States terrestrial radiation worker limits, derived from guidelines produced by scientific panels, do not apply to astronauts. Limits for astronauts have changed throughout the Space Age, eventually reaching the current National Aeronautics and Space Administration limit of 3% risk of exposure induced death, with an administrative stipulation that the risk be assured to the upper 95% confidence limit. Much effort has been spent on reducing the uncertainty associated with evaluating astronaut risk for radiogenic cancer mortality, while tools that affect the accuracy of the calculations have largely remained unchanged. In the present study, the impacts of using more realistic computational phantoms with size variability to represent astronauts with simplified deterministic radiation transport were evaluated. Next, the impacts of microgravity-induced body changes on space radiation dosimetry using the same transport method were investigated. Finally, dosimetry and risk calculations resulting from Monte Carlo radiation transport were compared with results obtained using simplified deterministic radiation transport. The results of the present study indicated that the use of phantoms that more accurately represent human anatomy can substantially improve space radiation dose estimates, most notably for exposures from solar particle events under light shielding conditions. Microgravity-induced changes were less important, but results showed that flexible phantoms could assist in optimizing astronaut body position for reducing exposures during solar particle events. Finally, little overall differences in risk calculations using simplified deterministic radiation transport and 3D Monte Carlo radiation transport were found; however, for the galactic cosmic ray ion spectra, compensating errors were observed for the constituent ions, thus exhibiting the need to perform evaluations on a particle

  20. [Radiation emergency medical preparedness in Japan--lessons learned from the Fukushima accident].

    PubMed

    Akashi, Makoto; Tominaga, Takako; Takabatake, Takashi; Michikawa, Yuichi; Hachiya, Misao

    2012-03-01

    Although radiation exposure accidents fortunately occur only rarely, potential sources for exposure accidents can be found anywhere. When persons are accidentally exposed to radiation, physicians may be involved in their assessment and care; of course, their early diagnosis and dose assessment are crucial. After the criticality accident at Tokaimura in 1999, the system of radiation emergency medical preparedness has been further strengthened for nuclear facilities in Japan. In the revised system, hospitals involved were classified into three levels, depending on their locations and capabilities. The Great East Japan Earthquake attacked the Pacific coast area of eastern Japan on 11 March 2011. This earthquake and tsunami caused serious damage to the nuclear power plants of Tokyo Electric Power Co.(TEPCO) in Fukushima Prefecture; a large amount of radionuclides such as iodine and cesium were released into the environment. Since the revised system was focused on treatment of heavily exposed patients and knowledge on radiation was not enough for medical staff, many problems were raised at hospitals and fire departments in this disaster.

  1. ``In vivo'' Dosimetry in Tangential and Axilosupraclavicular Radiation Fields for Breast Cancer Postmastectomy''

    NASA Astrophysics Data System (ADS)

    García, Heredia A.; Ruiz, Trejo C. G.; Gamboa de Buen, I.; Poitevin, Chacón M. A.; Flores, J. M. Castro; Rodríguez, M. Ponce; Ángeles, Zaragoza S. O.; Buenfil, Burgos A. E.

    2008-08-01

    This work is an "in vivo" dosimetry study for breast cancer patients, treated with external radiotherapy. Patients who have suffered a modified radical mastectomy have been included in the study. Measurements will be made with thermoluminescent dosimeters and with radiochromic films. Such dosimetry will let us know the dose distribution in the zone which the applied beams overlap and compare the measureddose with that calculated one using the Eclipse 6.5 (Varian) planning system.

  2. Radiation Dosimetry Experiment (RaD-X): High-Altitude Balloon Flight Mission for Improving the NAIRAS Model

    NASA Technical Reports Server (NTRS)

    Mertens, Christopher J.; Alston, Erica J.; Straume, Tore; Gersey, Brad; Lusby, Terry C.; Norman, Ryan B.; Gronoff, Guillaume P.; Tobiska, W. Kent; Wilkins, Rick

    2015-01-01

    The NASA Radiation Dosimetry Experiment (RaD-X) high-altitude balloon mission was successfully launched from Fort Sumner, New Mexico USA on 25 September, 2015. Over 15 hours of science data were obtained from four dosimeters at altitudes above about 25 km. One of the main goals of the RaD-X mission is to improve aviation radiation model characterization of cosmic ray primaries by taking dosimetric measurements above the Pfotzer maximum before the production of secondary particles occurs. The second goal of the RaD-X mission is to facilitate the pathway toward real-time, data assimilative predictions of atmospheric cosmic radiation exposure by identifying and characterizing low-cost radiation measurement solutions.

  3. SU-E-J-17: A Study of Accelerator-Induced Cerenkov Radiation as a Beam Diagnostic and Dosimetry Tool

    SciTech Connect

    Bateman, F; Tosh, R

    2014-06-01

    Purpose: To investigate accelerator-induced Cerenkov radiation imaging as a possible beam diagnostic and medical dosimetry tool. Methods: Cerenkov emission produced by clinical accelerator beams in a water phantom was imaged using a camera system comprised of a high-sensitivity thermoelectrically-cooled CCD camera coupled to a large aperture (f/0.75) objective lens with 16:1 magnification. This large format lens allows a significant amount of the available Cerenkov light to be collected and focused onto the CCD camera to form the image. Preliminary images, obtained with 6 MV photon beams, used an unshielded camera mounted horizontally with the beam normal to the water surface, and confirmed the detection of Cerenkov radiation. Several improvements were subsequently made including the addition of radiation shielding around the camera, and altering of the beam and camera angles to give a more favorable geometry for Cerenkov light collection. A detailed study was then undertaken over a range of electron and photon beam energies and dose rates to investigate the possibility of using this technique for beam diagnostics and dosimetry. Results: A series of images were obtained at a fixed dose rate over a range of electron energies from 6 to 20 MeV. The location of maximum intensity was found to vary linearly with the energy of the beam. A linear relationship was also found between the light observed from a fixed point on the central axis and the dose rate for both photon and electron beams. Conclusion: We have found that the analysis of images of beam-induced Cerenkov light in a water phantom has potential for use as a beam diagnostic and medical dosimetry tool. Our future goals include the calibration of the light output in terms of radiation dose and development of a tomographic system for 3D Cerenkov imaging in water phantoms and other media.

  4. A review of dosimetry studies on external-beam radiation treatment with respect to second cancer induction

    PubMed Central

    Xu, X George; Bednarz, Bryan; Paganetti, Harald

    2014-01-01

    It has been long known that patients treated with ionizing radiation carry a risk of developing a second cancer in their lifetimes. Factors contributing to the recently renewed concern about the second cancer include improved cancer survival rate, younger patient population as well as emerging treatment modalities such as intensity-modulated radiation treatment (IMRT) and proton therapy that can potentially elevate secondary exposures to healthy tissues distant from the target volume. In the past 30 years, external-beam treatment technologies have evolved significantly, and a large amount of data exist but appear to be difficult to comprehend and compare. This review article aims to provide readers with an understanding of the principles and methods related to scattered doses in radiation therapy by summarizing a large collection of dosimetry and clinical studies. Basic concepts and terminology are introduced at the beginning. That is followed by a comprehensive review of dosimetry studies for external-beam treatment modalities including classical radiation therapy, 3D-conformal x-ray therapy, intensity-modulated x-ray therapy (IMRT and tomotherapy) and proton therapy. Selected clinical data on second cancer induction among radiotherapy patients are also covered. Problems in past studies and controversial issues are discussed. The needs for future studies are presented at the end. PMID:18540047

  5. TOPICAL REVIEW: A review of dosimetry studies on external-beam radiation treatment with respect to second cancer induction

    NASA Astrophysics Data System (ADS)

    Xu, X. George; Bednarz, Bryan; Paganetti, Harald

    2008-07-01

    It has been long known that patients treated with ionizing radiation carry a risk of developing a second cancer in their lifetimes. Factors contributing to the recently renewed concern about the second cancer include improved cancer survival rate, younger patient population as well as emerging treatment modalities such as intensity-modulated radiation treatment (IMRT) and proton therapy that can potentially elevate secondary exposures to healthy tissues distant from the target volume. In the past 30 years, external-beam treatment technologies have evolved significantly, and a large amount of data exist but appear to be difficult to comprehend and compare. This review article aims to provide readers with an understanding of the principles and methods related to scattered doses in radiation therapy by summarizing a large collection of dosimetry and clinical studies. Basic concepts and terminology are introduced at the beginning. That is followed by a comprehensive review of dosimetry studies for external-beam treatment modalities including classical radiation therapy, 3D-conformal x-ray therapy, intensity-modulated x-ray therapy (IMRT and tomotherapy) and proton therapy. Selected clinical data on second cancer induction among radiotherapy patients are also covered. Problems in past studies and controversial issues are discussed. The needs for future studies are presented at the end.

  6. Retrospective dosimetry of Iodine-131 exposures using Iodine-129 and Caesium-137 inventories in soils--A critical evaluation of the consequences of the Chernobyl accident in parts of Northern Ukraine.

    PubMed

    Michel, R; Daraoui, A; Gorny, M; Jakob, D; Sachse, R; Romantschuk, L D; Alfimov, V; Synal, H-A

    2015-12-01

    The radiation exposure of thyroid glands due to (131)I as a consequence of the Chernobyl accident was investigated retrospectively based on (129)I and (137)Cs inventories in soils in Northern Ukraine. To this end, soil samples from 60 settlements were investigated for (129)I, (127)I, and (137)Cs by AMS, ICP-MS and gamma-spectrometry, respectively. Sampling was performed between 2004 und 2007. In those parts of Northern Ukraine investigated here the (129)I and (137)Cs inventories are well correlated, the variability of the individual (129)I/(137)Cs ratios being, however, high. Both the (129)I and (137)Cs inventories in the individual 5 samples for each settlement allowed estimating the uncertainties of the inventories due to the variability of the radionuclide deposition and consequently of the retrospective dosimetry. Thyroid equivalent doses were calculated from the (129)I and the (137)Cs inventories using aggregated dose coefficients for 5-year old and 10-year-old children as well as for adults. The highest thyroid equivalent doses (calculated from (129)I inventories) were calculated for Wladimirowka with 30 Gy for 5-years-old children and 7 Gy for adults. In 35 settlements of contamination zone II the geometric mean of the thyroid equivalent doses was 2.0 Gy for 5-years-old children with a geometric standard deviation (GSD) of 3.0. For adults the geometric mean was 0.47 Gy also with a GSD of 3.0. In more than 25 settlements of contamination zone III the geometric means were 0.82 Gy for 5-years old children with a GSD of 1.8 and 0.21 Gy for adults (GSD 1.8). For 45 settlements, the results of the retrospective dosimetry could be compared with thyroid equivalent doses calculated using time-integrated (131)I activities of thyroids which were measured in 1986. Thus, a critical evaluation of the results was possible which demonstrated the general feasibility of the method, but also the associated uncertainties and limitations. PMID:26254721

  7. Retrospective dosimetry of Iodine-131 exposures using Iodine-129 and Caesium-137 inventories in soils--A critical evaluation of the consequences of the Chernobyl accident in parts of Northern Ukraine.

    PubMed

    Michel, R; Daraoui, A; Gorny, M; Jakob, D; Sachse, R; Romantschuk, L D; Alfimov, V; Synal, H-A

    2015-12-01

    The radiation exposure of thyroid glands due to (131)I as a consequence of the Chernobyl accident was investigated retrospectively based on (129)I and (137)Cs inventories in soils in Northern Ukraine. To this end, soil samples from 60 settlements were investigated for (129)I, (127)I, and (137)Cs by AMS, ICP-MS and gamma-spectrometry, respectively. Sampling was performed between 2004 und 2007. In those parts of Northern Ukraine investigated here the (129)I and (137)Cs inventories are well correlated, the variability of the individual (129)I/(137)Cs ratios being, however, high. Both the (129)I and (137)Cs inventories in the individual 5 samples for each settlement allowed estimating the uncertainties of the inventories due to the variability of the radionuclide deposition and consequently of the retrospective dosimetry. Thyroid equivalent doses were calculated from the (129)I and the (137)Cs inventories using aggregated dose coefficients for 5-year old and 10-year-old children as well as for adults. The highest thyroid equivalent doses (calculated from (129)I inventories) were calculated for Wladimirowka with 30 Gy for 5-years-old children and 7 Gy for adults. In 35 settlements of contamination zone II the geometric mean of the thyroid equivalent doses was 2.0 Gy for 5-years-old children with a geometric standard deviation (GSD) of 3.0. For adults the geometric mean was 0.47 Gy also with a GSD of 3.0. In more than 25 settlements of contamination zone III the geometric means were 0.82 Gy for 5-years old children with a GSD of 1.8 and 0.21 Gy for adults (GSD 1.8). For 45 settlements, the results of the retrospective dosimetry could be compared with thyroid equivalent doses calculated using time-integrated (131)I activities of thyroids which were measured in 1986. Thus, a critical evaluation of the results was possible which demonstrated the general feasibility of the method, but also the associated uncertainties and limitations.

  8. Implementation of talairach atlas based automated brain segmentation for radiation therapy dosimetry.

    PubMed

    Popple, R A; Griffith, H R; Sawrie, S M; Fiveash, J B; Brezovich, I A

    2006-02-01

    Radiotherapy for brain cancer inevitably results in irradiation of uninvolved brain. While it has been demonstrated that irradiation of the brain can result in cognitive deficits, dose-volume relationships are not well established. There is little work correlating a particular cognitive deficit with dose received by the region of the brain responsible for the specific cognitive function. One obstacle to such studies is that identification of brain anatomy is both labor intensive and dependent on the individual performing the segmentation. Automatic segmentation has the potential to be both efficient and consistent. Brains2 is a software package developed by the University of Iowa for MRI volumetric studies. It utilizes MR images, the Talairach atlas, and an artificial neural network (ANN) to segment brain images into substructures in a standardized manner. We have developed a software package, Brains2DICOM, that converts the regions of interest identified by Brains2 into a DICOM radiotherapy structure set. The structure set can be imported into a treatment planning system for dosimetry. We demonstrated the utility of Brains2DICOM using a test case, a 34-year-old man with diffuse astrocytoma treated with three-dimensional conformal radiotherapy. Brains2 successfully applied the Talairach atlas to identify the right and left frontal, parietal, temporal, occipital, subcortical, and cerebellum regions. Brains2 was not successful in applying the ANN to identify small structures, such as the hippocampus and caudate. Further work is necessary to revise the ANN or to develop new methods for identification of small structures in the presence of disease and radiation induced changes. The segmented regions-of-interest were transferred to our commercial treatment planning system using DICOM and dose-volume histograms were constructed. This method will facilitate the acquisition of data necessary for the development of normal tissue complication probability (NTCP) models that

  9. Potential of Hybrid Computational Phantoms for Retrospective Heart Dosimetry After Breast Radiation Therapy: A Feasibility Study

    SciTech Connect

    Moignier, Alexandra; Derreumaux, Sylvie; Broggio, David; Beurrier, Julien; Chea, Michel; Boisserie, Gilbert; Franck, Didier; Aubert, Bernard; Mazeron, Jean-Jacques

    2013-02-01

    Purpose: Current retrospective cardiovascular dosimetry studies are based on a representative patient or simple mathematic phantoms. Here, a process of patient modeling was developed to personalize the anatomy of the thorax and to include a heart model with coronary arteries. Methods and Materials: The patient models were hybrid computational phantoms (HCPs) with an inserted detailed heart model. A computed tomography (CT) acquisition (pseudo-CT) was derived from HCP and imported into a treatment planning system where treatment conditions were reproduced. Six current patients were selected: 3 were modeled from their CT images (A patients) and the others were modelled from 2 orthogonal radiographs (B patients). The method performance and limitation were investigated by quantitative comparison between the initial CT and the pseudo-CT, namely, the morphology and the dose calculation were compared. For the B patients, a comparison with 2 kinds of representative patients was also conducted. Finally, dose assessment was focused on the whole coronary artery tree and the left anterior descending coronary. Results: When 3-dimensional anatomic information was available, the dose calculations performed on the initial CT and the pseudo-CT were in good agreement. For the B patients, comparison of doses derived from HCP and representative patients showed that the HCP doses were either better or equivalent. In the left breast radiation therapy context and for the studied cases, coronary mean doses were at least 5-fold higher than heart mean doses. Conclusions: For retrospective dose studies, it is suggested that HCP offers a better surrogate, in terms of dose accuracy, than representative patients. The use of a detailed heart model eliminates the problem of identifying the coronaries on the patient's CT.

  10. Video-rate optical dosimetry and dynamic visualization of IMRT and VMAT treatment plans in water using Cherenkov radiation

    PubMed Central

    Glaser, Adam K.; Andreozzi, Jacqueline M.; Davis, Scott C.; Zhang, Rongxiao; Pogue, Brian W.; Fox, Colleen J.; Gladstone, David J.

    2014-01-01

    Purpose: A novel technique for optical dosimetry of dynamic intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) plans was investigated for the first time by capturing images of the induced Cherenkov radiation in water. Methods: A high-sensitivity, intensified CCD camera (ICCD) was configured to acquire a two-dimensional (2D) projection image of the Cherenkov radiation induced by IMRT and VMAT plans, based on the Task Group 119 (TG-119) C-Shape geometry. Plans were generated using the Varian Eclipse treatment planning system (TPS) and delivered using 6 MV x-rays from a Varian TrueBeam Linear Accelerator (Linac) incident on a water tank doped with the fluorophore quinine sulfate. The ICCD acquisition was gated to the Linac target trigger pulse to reduce background light artifacts, read out for a single radiation pulse, and binned to a resolution of 512 × 512 pixels. The resulting videos were analyzed temporally for various regions of interest (ROI) covering the planning target volume (PTV) and organ at risk (OAR), and summed to obtain an overall light intensity distribution, which was compared to the expected dose distribution from the TPS using a gamma-index analysis. Results: The chosen camera settings resulted in 23.5 frames per second dosimetry videos. Temporal intensity plots of the PTV and OAR ROIs confirmed the preferential delivery of dose to the PTV versus the OAR, and the gamma analysis yielded 95.9% and 96.2% agreement between the experimentally captured Cherenkov light distribution and expected TPS dose distribution based upon a 3%/3 mm dose difference and distance-to-agreement criterion for the IMRT and VMAT plans, respectively. Conclusions: The results from this initial study demonstrate the first documented use of Cherenkov radiation for video-rate optical dosimetry of dynamic IMRT and VMAT treatment plans. The proposed modality has several potential advantages over alternative methods including the real

  11. Video-rate optical dosimetry and dynamic visualization of IMRT and VMAT treatment plans in water using Cherenkov radiation

    SciTech Connect

    Glaser, Adam K. E-mail: Brian.W.Pogue@dartmouth.edu; Andreozzi, Jacqueline M.; Davis, Scott C.; Zhang, Rongxiao; Pogue, Brian W. E-mail: Brian.W.Pogue@dartmouth.edu; Fox, Colleen J.; Gladstone, David J.

    2014-06-15

    Purpose: A novel technique for optical dosimetry of dynamic intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) plans was investigated for the first time by capturing images of the induced Cherenkov radiation in water. Methods: A high-sensitivity, intensified CCD camera (ICCD) was configured to acquire a two-dimensional (2D) projection image of the Cherenkov radiation induced by IMRT and VMAT plans, based on the Task Group 119 (TG-119) C-Shape geometry. Plans were generated using the Varian Eclipse treatment planning system (TPS) and delivered using 6 MV x-rays from a Varian TrueBeam Linear Accelerator (Linac) incident on a water tank doped with the fluorophore quinine sulfate. The ICCD acquisition was gated to the Linac target trigger pulse to reduce background light artifacts, read out for a single radiation pulse, and binned to a resolution of 512 × 512 pixels. The resulting videos were analyzed temporally for various regions of interest (ROI) covering the planning target volume (PTV) and organ at risk (OAR), and summed to obtain an overall light intensity distribution, which was compared to the expected dose distribution from the TPS using a gamma-index analysis. Results: The chosen camera settings resulted in 23.5 frames per second dosimetry videos. Temporal intensity plots of the PTV and OAR ROIs confirmed the preferential delivery of dose to the PTV versus the OAR, and the gamma analysis yielded 95.9% and 96.2% agreement between the experimentally captured Cherenkov light distribution and expected TPS dose distribution based upon a 3%/3 mm dose difference and distance-to-agreement criterion for the IMRT and VMAT plans, respectively. Conclusions: The results from this initial study demonstrate the first documented use of Cherenkov radiation for video-rate optical dosimetry of dynamic IMRT and VMAT treatment plans. The proposed modality has several potential advantages over alternative methods including the real

  12. Medical preparedness in radiation accidents: a matter of logistics and communication not treatment!

    PubMed

    Staudenherz, A; Leitha, T

    2011-07-01

    The currently reactor wreckage in Fukushima raised the following important questions: Is our knowledge of the possible dangers of ionizing radiation sufficient to warrant special action? What is the role of the medical community in technical radiation accidents from Windscale to Fukushima? What is the role of the medical community in terrorist radiation attacks? Are we prepared for those challenges? How can medical services communicate information in the media framework? What have we learned recently? And, what should be improved? In this review of the current literature on ionizing radiation, we try to answer these questions. Our conclusion is that medical services have to improve their communication skills and convince the public that the dangers of ionizing radiation can be quantitated within certain limits to support a qualified discussion about its risks and benefits. PMID:23022830

  13. Chernobyl Nuclear Reactor accident fallout: Measurement and consequences. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1996-11-01

    The bibliography contains citations concerning the consequences of radioactive fallout from the Chernobyl nuclear reactor accident. Citations discuss radioactive monitoring, health hazards, and radiation dosimetry. Radiation contamination in the air, soil, vegetation, and food is examined. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  14. Chernobyl nuclear reactor accident fallout: Measurement and consequences. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1995-02-01

    The bibliography contains citations concerning the consequences of radioactive fallout from the Chernobyl nuclear reactor accident. Citations discuss radioactive monitoring, health hazards, and radiation dosimetry. Radiation contamination in the air, soil, vegetation, and food is examined. (Contains a minimum of 247 citations and includes a subject term index and title list.)

  15. Chernobyl nuclear reactor accident fallout: Measurement and consequences. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1996-01-01

    The bibliography contains citations concerning the consequences of radioactive fallout from the Chernobyl nuclear reactor accident. Citations discuss radioactive monitoring, health hazards, and radiation dosimetry. Radiation contamination in the air, soil, vegetation, and food is examined. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  16. Chernobyl nuclear reactor accident fallout: Measurement and consequences. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    1994-01-01

    The bibliography contains citations concerning the consequences of radioactive fallout from the Chernobyl nuclear reactor accident. Citations discuss radioactive monitoring, health hazards, and radiation dosimetry. Radiation contamination in the air, soil, vegetation, and food is examined. (Contains a minimum of 210 citations and includes a subject term index and title list.)

  17. Chernobyl nuclear reactor accident fallout: Measurement and consequences. (Latest citations from the NTIS Bibliographic database). Published Search

    SciTech Connect

    1993-09-01

    The bibliography contains citations concerning the consequences of radioactive fallout from the Chernobyl nuclear reactor accident. Citations discuss radioactive monitoring, health hazards, and radiation dosimetry. Radiation contamination in the air, soil, vegetation, and food is examined. (Contains a minimum of 208 citations and includes a subject term index and title list.)

  18. Perception of Radiation Risk by Japanese Radiation Specialists Evaluated as a Safe Dose Before the Fukushima Nuclear Accident.

    PubMed

    Miura, Miwa; Ono, Koji; Yamauchi, Motohiro; Matsuda, Naoki

    2016-06-01

    From October to December 2010, just before the radiological accident at the Fukushima Daiichi nuclear power plant, 71 radiation professionals from radiation facilities in Japan were asked what they considered as a "safe dose" of radiation for themselves, their partners, parents, children, siblings, and friends. Although the 'safe dose' they noted varied widely, from less than 1 mSv y to more than 100 mSv y, the average dose was 35.6 mSv y, which is around the middle point between the legal exposure dose limits for the annual average and for any single year. Similar results were obtained from other surveys of members of the Japan Radioisotope Association (36.9 mSv y) and of the Oita Prefectural Hospital (36.8 mSv y). Among family members and friends, the minimum average "safe" dose was 8.5 mSv y for children, for whom 50% of the responders claimed a "safe dose" of less than 1 mSv. Gender, age and specialty of the radiation professional also affected their notion of a "safe dose." These findings suggest that the perception of radiation risk varies widely even for radiation professionals and that the legal exposure dose limits derived from regulatory science may act as an anchor of safety. The different levels of risk perception for different target groups among radiation professionals appear similar to those in the general population. The gap between these characteristics of radiation professionals and the generally accepted picture of radiation professionals might have played a role in the state of confusion after the radiological accident.

  19. Perception of Radiation Risk by Japanese Radiation Specialists Evaluated as a Safe Dose Before the Fukushima Nuclear Accident.

    PubMed

    Miura, Miwa; Ono, Koji; Yamauchi, Motohiro; Matsuda, Naoki

    2016-06-01

    From October to December 2010, just before the radiological accident at the Fukushima Daiichi nuclear power plant, 71 radiation professionals from radiation facilities in Japan were asked what they considered as a "safe dose" of radiation for themselves, their partners, parents, children, siblings, and friends. Although the 'safe dose' they noted varied widely, from less than 1 mSv y to more than 100 mSv y, the average dose was 35.6 mSv y, which is around the middle point between the legal exposure dose limits for the annual average and for any single year. Similar results were obtained from other surveys of members of the Japan Radioisotope Association (36.9 mSv y) and of the Oita Prefectural Hospital (36.8 mSv y). Among family members and friends, the minimum average "safe" dose was 8.5 mSv y for children, for whom 50% of the responders claimed a "safe dose" of less than 1 mSv. Gender, age and specialty of the radiation professional also affected their notion of a "safe dose." These findings suggest that the perception of radiation risk varies widely even for radiation professionals and that the legal exposure dose limits derived from regulatory science may act as an anchor of safety. The different levels of risk perception for different target groups among radiation professionals appear similar to those in the general population. The gap between these characteristics of radiation professionals and the generally accepted picture of radiation professionals might have played a role in the state of confusion after the radiological accident. PMID:27115222

  20. Computational lymphatic node models in pediatric and adult hybrid phantoms for radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Lee, Choonsik; Lamart, Stephanie; Moroz, Brian E.

    2013-03-01

    We developed models of lymphatic nodes for six pediatric and two adult hybrid computational phantoms to calculate the lymphatic node dose estimates from external and internal radiation exposures. We derived the number of lymphatic nodes from the recommendations in International Commission on Radiological Protection (ICRP) Publications 23 and 89 at 16 cluster locations for the lymphatic nodes: extrathoracic, cervical, thoracic (upper and lower), breast (left and right), mesentery (left and right), axillary (left and right), cubital (left and right), inguinal (left and right) and popliteal (left and right), for different ages (newborn, 1-, 5-, 10-, 15-year-old and adult). We modeled each lymphatic node within the voxel format of the hybrid phantoms by assuming that all nodes have identical size derived from published data except narrow cluster sites. The lymph nodes were generated by the following algorithm: (1) selection of the lymph node site among the 16 cluster sites; (2) random sampling of the location of the lymph node within a spherical space centered at the chosen cluster site; (3) creation of the sphere or ovoid of tissue representing the node based on lymphatic node characteristics defined in ICRP Publications 23 and 89. We created lymph nodes until the pre-defined number of lymphatic nodes at the selected cluster site was reached. This algorithm was applied to pediatric (newborn, 1-, 5-and 10-year-old male, and 15-year-old males) and adult male and female ICRP-compliant hybrid phantoms after voxelization. To assess the performance of our models for internal dosimetry, we calculated dose conversion coefficients, called S values, for selected organs and tissues with Iodine-131 distributed in six lymphatic node cluster sites using MCNPX2.6, a well validated Monte Carlo radiation transport code. Our analysis of the calculations indicates that the S values were significantly affected by the location of the lymph node clusters and that the values increased for

  1. The UF family of reference hybrid phantoms for computational radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Lee, Choonsik; Lodwick, Daniel; Hurtado, Jorge; Pafundi, Deanna; Williams, Jonathan L.; Bolch, Wesley E.

    2010-01-01

    Computational human phantoms are computer models used to obtain dose distributions within the human body exposed to internal or external radiation sources. In addition, they are increasingly used to develop detector efficiencies for in vivo whole-body counters. Two classes of computational human phantoms have been widely utilized for dosimetry calculation: stylized and voxel phantoms that describe human anatomy through mathematical surface equations and 3D voxel matrices, respectively. Stylized phantoms are flexible in that changes to organ position and shape are possible given avoidance of region overlap, while voxel phantoms are typically fixed to a given patient anatomy, yet can be proportionally scaled to match individuals of larger or smaller stature, but of equivalent organ anatomy. Voxel phantoms provide much better anatomical realism as compared to stylized phantoms which are intrinsically limited by mathematical surface equations. To address the drawbacks of these phantoms, hybrid phantoms based on non-uniform rational B-spline (NURBS) surfaces have been introduced wherein anthropomorphic flexibility and anatomic realism are both preserved. Researchers at the University of Florida have introduced a series of hybrid phantoms representing the ICRP Publication 89 reference newborn, 15 year, and adult male and female. In this study, six additional phantoms are added to the UF family of hybrid phantoms—those of the reference 1 year, 5 year and 10 year child. Head and torso CT images of patients whose ages were close to the targeted ages were obtained under approved protocols. Major organs and tissues were segmented from these images using an image processing software, 3D-DOCTOR™. NURBS and polygon mesh surfaces were then used to model individual organs and tissues after importing the segmented organ models to the 3D NURBS modeling software, Rhinoceros™. The phantoms were matched to four reference datasets: (1) standard anthropometric data, (2) reference

  2. Computational lymphatic node models in pediatric and adult hybrid phantoms for radiation dosimetry.

    PubMed

    Lee, Choonsik; Lamart, Stephanie; Moroz, Brian E

    2013-03-01

    We developed models of lymphatic nodes for six pediatric and two adult hybrid computational phantoms to calculate the lymphatic node dose estimates from external and internal radiation exposures. We derived the number of lymphatic nodes from the recommendations in International Commission on Radiological Protection (ICRP) Publications 23 and 89 at 16 cluster locations for the lymphatic nodes: extrathoracic, cervical, thoracic (upper and lower), breast (left and right), mesentery (left and right), axillary (left and right), cubital (left and right), inguinal (left and right) and popliteal (left and right), for different ages (newborn, 1-, 5-, 10-, 15-year-old and adult). We modeled each lymphatic node within the voxel format of the hybrid phantoms by assuming that all nodes have identical size derived from published data except narrow cluster sites. The lymph nodes were generated by the following algorithm: (1) selection of the lymph node site among the 16 cluster sites; (2) random sampling of the location of the lymph node within a spherical space centered at the chosen cluster site; (3) creation of the sphere or ovoid of tissue representing the node based on lymphatic node characteristics defined in ICRP Publications 23 and 89. We created lymph nodes until the pre-defined number of lymphatic nodes at the selected cluster site was reached. This algorithm was applied to pediatric (newborn, 1-, 5-and 10-year-old male, and 15-year-old males) and adult male and female ICRP-compliant hybrid phantoms after voxelization. To assess the performance of our models for internal dosimetry, we calculated dose conversion coefficients, called S values, for selected organs and tissues with Iodine-131 distributed in six lymphatic node cluster sites using MCNPX2.6, a well validated Monte Carlo radiation transport code. Our analysis of the calculations indicates that the S values were significantly affected by the location of the lymph node clusters and that the values increased for

  3. Preclinical acute toxicity, biodistribution, pharmacokinetics, radiation dosimetry and microPET imaging studies of [(18)F]fluorocholine in mice.

    PubMed

    Silveira, Marina B; Ferreira, Soraya M Z M D; Nascimento, Leonardo T C; Costa, Flávia M; Mendes, Bruno M; Ferreira, Andrea V; Malamut, Carlos; Silva, Juliana B; Mamede, Marcelo

    2016-10-01

    [(18)F]Fluorocholine ([(18)F]FCH) has been proven to be effective in prostate cancer. Since [(18)F]FCH is classified as a new radiopharmaceutical in Brazil, preclinical safety and efficacy data are required to support clinical trials and to obtain its approval. The aim of this work was to perform acute toxicity, biodistribution, pharmacokinetics, radiation dosimetry and microPET imaging studies of [(18)F]FCH. The results could support its use in nuclear medicine as an important piece of work for regulatory in Brazil.

  4. Preclinical acute toxicity, biodistribution, pharmacokinetics, radiation dosimetry and microPET imaging studies of [(18)F]fluorocholine in mice.

    PubMed

    Silveira, Marina B; Ferreira, Soraya M Z M D; Nascimento, Leonardo T C; Costa, Flávia M; Mendes, Bruno M; Ferreira, Andrea V; Malamut, Carlos; Silva, Juliana B; Mamede, Marcelo

    2016-10-01

    [(18)F]Fluorocholine ([(18)F]FCH) has been proven to be effective in prostate cancer. Since [(18)F]FCH is classified as a new radiopharmaceutical in Brazil, preclinical safety and efficacy data are required to support clinical trials and to obtain its approval. The aim of this work was to perform acute toxicity, biodistribution, pharmacokinetics, radiation dosimetry and microPET imaging studies of [(18)F]FCH. The results could support its use in nuclear medicine as an important piece of work for regulatory in Brazil. PMID:27509594

  5. A computational tool for patient specific dosimetry and radiobiological modeling of selective internal radiation therapy with (90)Y microspheres.

    PubMed

    Kalantzis, Georgios; Leventouri, Theodora; Apte, Aditiya; Shang, Charles

    2015-11-01

    In recent years we have witnessed tremendous progress in selective internal radiation therapy. In clinical practice, quite often, radionuclide therapy is planned using simple models based on standard activity values or activity administered per unit body weight or surface area in spite of the admission that radiation-dose methods provide more accurate dosimetric results. To address that issue, the authors developed a Matlab-based computational software, named Patient Specific Yttrium-90 Dosimetry Toolkit (PSYDT). PSYDT was designed for patient specific voxel-based dosimetric calculations and radiobiological modeling of selective internal radiation therapy with (90)Y microspheres. The developed toolkit is composed of three dimensional dose calculations for both bremsstrahlung and beta emissions. Subsequently, radiobiological modeling is performed on a per-voxel basis and cumulative dose volume histograms (DVHs) are generated. In this report we describe the functionality and visualization features of PSYDT. PMID:26296058

  6. Monte Carlo modeling in CT-based geometries: dosimetry for biological modeling experiments with particle beam radiation.

    PubMed

    Diffenderfer, Eric S; Dolney, Derek; Schaettler, Maximilian; Sanzari, Jenine K; McDonough, James; Cengel, Keith A

    2014-03-01

    The space radiation environment imposes increased dangers of exposure to ionizing radiation, particularly during a solar particle event (SPE). These events consist primarily of low energy protons that produce a highly inhomogeneous dose distribution. Due to this inherent dose heterogeneity, experiments designed to investigate the radiobiological effects of SPE radiation present difficulties in evaluating and interpreting dose to sensitive organs. To address this challenge, we used the Geant4 Monte Carlo simulation framework to develop dosimetry software that uses computed tomography (CT) images and provides radiation transport simulations incorporating all relevant physical interaction processes. We found that this simulation accurately predicts measured data in phantoms and can be applied to model dose in radiobiological experiments with animal models exposed to charged particle (electron and proton) beams. This study clearly demonstrates the value of Monte Carlo radiation transport methods for two critically interrelated uses: (i) determining the overall dose distribution and dose levels to specific organ systems for animal experiments with SPE-like radiation, and (ii) interpreting the effect of random and systematic variations in experimental variables (e.g. animal movement during long exposures) on the dose distributions and consequent biological effects from SPE-like radiation exposure. The software developed and validated in this study represents a critically important new tool that allows integration of computational and biological modeling for evaluating the biological outcomes of exposures to inhomogeneous SPE-like radiation dose distributions, and has potential applications for other environmental and therapeutic exposure simulations.

  7. 3D dosimetry estimation for selective internal radiation therapy (SIRT) using SPECT/CT images: a phantom study

    NASA Astrophysics Data System (ADS)

    Debebe, Senait A.; Franquiz, Juan; McGoron, Anthony J.

    2015-03-01

    Selective Internal Radiation Therapy (SIRT) is a common way to treat liver cancer that cannot be treated surgically. SIRT involves administration of Yttrium - 90 (90Y) microspheres via the hepatic artery after a diagnostic procedure using 99mTechnetium (Tc)-macroaggregated albumin (MAA) to detect extrahepatic shunting to the lung or the gastrointestinal tract. Accurate quantification of radionuclide administered to patients and radiation dose absorbed by different organs is of importance in SIRT. Accurate dosimetry for SIRT allows optimization of dose delivery to the target tumor and may allow for the ability to assess the efficacy of the treatment. In this study, we proposed a method that can efficiently estimate radiation absorbed dose from 90Y bremsstrahlung SPECT/CT images of liver and the surrounding organs. Bremsstrahlung radiation from 90Y was simulated using the Compton window of 99mTc (78keV at 57%). 99mTc images acquired at the photopeak energy window were used as a standard to examine the accuracy of dosimetry prediction by the simulated bremsstrahlung images. A Liqui-Phil abdominal phantom with liver, stomach and two tumor inserts was imaged using a Philips SPECT/CT scanner. The Dose Point Kernel convolution method was used to find the radiation absorbed dose at a voxel level for a three dimensional dose distribution. This method will allow for a complete estimate of the distribution of radiation absorbed dose by tumors, liver, stomach and other surrounding organs at the voxel level. The method provides a quantitative predictive method for SIRT treatment outcome and administered dose response for patients who undergo the treatment.

  8. Final Report Summary: Radiation dosimetry of Cu-64-labeled radiotherapy agents using PET [Positron Emission Tomography

    SciTech Connect

    Anderson, Carolyn J.; Cutler, P.D.

    2002-09-01

    This project began in 1996, and was completed in July 2001. The overall goals were to compare various methods of dosimetry of PET imaging agents, as well as develop more optimal methods. One of the major accomplishments of this grant was the human PET imaging studies of a positron-emitting radiopharmaceutical for somatostatin-receptor imaging, and subsequent dosimetry calculations resulting from this study. In addition, we collaborated with Darrell Fisher and Edmund Hui to develop a MIRD-hamster program for calculating hamster organ and tumor dosimetry in hamster models. Progress was made towards a point kernel approach to more accurately determining absorbed doses to normal organs, as well as towards co-registration of PET and MRI images. This report focuses on the progress made in the last 15 months of the grant, which in general is a summary of the progress over the 5 years the project was ongoing.

  9. Dose evaluation in criticality accidents using response of Panasonic TL personal dosemeters (UD-809/UD-802).

    PubMed

    Zeyrek, C T; Gündüz, H

    2012-09-01

    This study gives the results of dosimetry measurements carried out in the Silène reactor at Valduc (France) with neutron and photon personal thermoluminescence dosemeters (TLDs) in mixed neutron and gamma radiation fields, in the frame of the international accident dosimetry intercomparison programme in 2002. The intercomparison consisted of a series of three irradiation scenarios. The scenarios took place at the Valduc site (France) by using the Silène experimental reactor. For neutron and photon dosimetry, Panasonic model UD-809 and UD-802 personal TLDs were used together. PMID:22389154

  10. Study of the secondary neutral radiation in proton therapy: Toward an indirect in vivo dosimetry

    SciTech Connect

    Carnicer, A.; Letellier, V.; Rucka, G.; Angellier, G.; Sauerwein, W.; Herault, J.

    2012-12-15

    Purpose: Secondary particles produced in the collision of protons with beam modifiers are of concern in proton therapy. Nevertheless, secondary radiation can provide information on the dosimetric parameters through its dependency on the modulating accessories (range shifter and range modulating wheel). Relatively little data have been reported in the literature for low-energy proton beams. The present study aims at characterizing the neutron and photon secondary radiation at the low-energy proton therapy facility of the Centre Antoine Lacassagne (CAL), and studying their correlation to the dosimetric parameters to explore possible practical uses of secondary radiation in the treatment quality for proton therapy. Methods: The Monte Carlo code MCNPX was used to simulate the proton therapy facility at CAL. Neutron and photon fluence, {Phi}, and ambient dose equivalent per proton dose, H*(10)/D, were determined across the horizontal main plane spanning the whole treatment room. H*(10)/D was also calculated at two positions of the treatment room where dosimetric measurements were performed for validation of the Monte Carlo calculations. Calculations and measurements were extended to 100 clinical spread-out Bragg Peaks (SOBPs) covering the whole range of therapeutic dose rates (D/MU) employed at CAL. In addition, the values of D and MU were also calculated for each SOBP and the results analyzed to study the relationship between secondary radiation and dosimetric parameters. Results: The largest production of the secondary particles takes place at the modulating devices and the brass collimators located along the optical bench. Along the beam line and off the beam axis to 2.5 m away, H*(10)/D values ranged from 5.4 {mu}Sv/Gy to 5.3 mSv/Gy for neutrons, and were 1 order of magnitude lower for photons. H*(10)/D varied greatly with the distance and angle to the beam axis. A variation of a factor of 5 was found for the different range of modulations (SOBPs). The ratios

  11. Experimental assessment of gold nanoparticle-mediated dose enhancement in radiation therapy beams using electron spin resonance dosimetry.

    PubMed

    Wolfe, T; Guidelli, E J; Gómez, J A; Baffa, O; Nicolucci, P

    2015-06-01

    In this work, we aim to experimentally assess increments of dose due to nanoparticle-radiation interactions via electron spin resonance (ESR) dosimetry performed with a biological-equivalent sensitive material.We employed 2-Methyl-Alanine (2MA) in powder form to compose the radiation sensitive medium embedding gold nanoparticles (AuNPs) 5 nm in diameter. Dosimeters manufactured with 0.1% w/w of AuNPs or no nanoparticles were irradiated with clinically utilized 250 kVp orthovoltage or 6 MV linac x-rays in dosimetric conditions. Amplitude peak-to-peak (App) at the central ESR spectral line was used for dosimetry. Dose-response curves were obtained for samples with or without nanoparticles and each energy beam. Dose increments due to nanoparticles were analyzed in terms of absolute dose enhancements (DEs), calculated as App ratios for each dose/beam condition, or relative dose enhancement factors (DEFs) calculated as the slopes of the dose-response curves.Dose enhancements were observed to present an amplified behavior for small doses (between 0.1-0.5 Gy), with this effect being more prominent with the kV beam. For doses between 0.5-5 Gy, dose-independent trends were observed for both beams, stable around (2.1   ±   0.7) and (1.3   ±   0.4) for kV and MV beams, respectively. We found DEFs of (1.62   ±   0.04) or (1.27   ±   0.03) for the same beams. Additionally, we measured no interference between AuNPs and the ESR apparatus, including the excitation microwaves, the magnetic fields and the paramagnetic radicals.2MA was demonstrated to be a feasible paramagnetic radiation-sensitive material for dosimetry in the presence of AuNPs, and ESR dosimetry a powerful experimental method for further verifications of increments in nanoparticle-mediated doses of biological interest. Ultimately, gold nanoparticles can cause significant and detectable dose enhancements in biological-like samples irradiated at both kilo

  12. Experimental assessment of gold nanoparticle-mediated dose enhancement in radiation therapy beams using electron spin resonance dosimetry

    NASA Astrophysics Data System (ADS)

    Wolfe, T.; Guidelli, E. J.; Gómez, J. A.; Baffa, O.; Nicolucci, P.

    2015-06-01

    In this work, we aim to experimentally assess increments of dose due to nanoparticle-radiation interactions via electron spin resonance (ESR) dosimetry performed with a biological-equivalent sensitive material. We employed 2-Methyl-Alanine (2MA) in powder form to compose the radiation sensitive medium embedding gold nanoparticles (AuNPs) 5 nm in diameter. Dosimeters manufactured with 0.1% w/w of AuNPs or no nanoparticles were irradiated with clinically utilized 250 kVp orthovoltage or 6 MV linac x-rays in dosimetric conditions. Amplitude peak-to-peak (App) at the central ESR spectral line was used for dosimetry. Dose-response curves were obtained for samples with or without nanoparticles and each energy beam. Dose increments due to nanoparticles were analyzed in terms of absolute dose enhancements (DEs), calculated as App ratios for each dose/beam condition, or relative dose enhancement factors (DEFs) calculated as the slopes of the dose-response curves. Dose enhancements were observed to present an amplified behavior for small doses (between 0.1-0.5 Gy), with this effect being more prominent with the kV beam. For doses between 0.5-5 Gy, dose-independent trends were observed for both beams, stable around (2.1   ±   0.7) and (1.3   ±   0.4) for kV and MV beams, respectively. We found DEFs of (1.62   ±   0.04) or (1.27   ±   0.03) for the same beams. Additionally, we measured no interference between AuNPs and the ESR apparatus, including the excitation microwaves, the magnetic fields and the paramagnetic radicals. 2MA was demonstrated to be a feasible paramagnetic radiation-sensitive material for dosimetry in the presence of AuNPs, and ESR dosimetry a powerful experimental method for further verifications of increments in nanoparticle-mediated doses of biological interest. Ultimately, gold nanoparticles can cause significant and detectable dose enhancements in biological-like samples irradiated at both

  13. Radiation-Driven Migration: The Case of Minamisoma City, Fukushima, Japan, after the Fukushima Nuclear Accident

    PubMed Central

    Zhang, Hui; Yan, Wanglin; Oba, Akihiro; Zhang, Wei

    2014-01-01

    The emigration of residents following the Fukushima nuclear accident has resulted in aging and depopulation problems in radiation-contaminated areas. The recovery of affected areas, and even those areas with low radioactive pollution levels, is still heavily affected by this problem. This slow recovery consequently affects immigration patterns. This review aims to present possible factors that have contributed to this dilemma. We first present an overview of the evacuation protocol that was administered in the study area following the Fukushima accident. We then analyze characteristics of the subsequent exodus by comparing population data for both before and after the accident. Based on the findings of existing literature, we identify three causes of emigration: (1) The health risks of living in a low radiation zone are still unknown; (2) The post-disaster psychological disturbance and distrust of government information promotes the emigration of evacuees; (3) an absence of economic vitality and of a leading industry renders the area less attractive to individuals residing outside of the city. Further research is needed on this issue, especially with respect to countermeasures for addressing this problem. PMID:25207491

  14. Radiation-driven migration: the case of Minamisoma City, Fukushima, Japan, after the Fukushima nuclear accident.

    PubMed

    Zhang, Hui; Yan, Wanglin; Oba, Akihiro; Zhang, Wei

    2014-09-09

    The emigration of residents following the Fukushima nuclear accident has resulted in aging and depopulation problems in radiation-contaminated areas. The recovery of affected areas, and even those areas with low radioactive pollution levels, is still heavily affected by this problem. This slow recovery consequently affects immigration patterns. This review aims to present possible factors that have contributed to this dilemma. We first present an overview of the evacuation protocol that was administered in the study area following the Fukushima accident. We then analyze characteristics of the subsequent exodus by comparing population data for both before and after the accident. Based on the findings of existing literature, we identify three causes of emigration: (1) The health risks of living in a low radiation zone are still unknown; (2) The post-disaster psychological disturbance and distrust of government information promotes the emigration of evacuees; (3) an absence of economic vitality and of a leading industry renders the area less attractive to individuals residing outside of the city. Further research is needed on this issue, especially with respect to countermeasures for addressing this problem.

  15. Female reproductive function in areas affected by radiation after the Chernobyl power station accident

    SciTech Connect

    Kulakov, V.I.; Sokur, T.N.; Volobuev, A.I.

    1993-07-01

    This paper reports the results of a comprehensive survey of the effects of the accidental release of radiation caused by the accident at the Chernobyl nuclear power station in April 1986. The accident and the resulting release of radiation and radioactive products into the atmosphere produced the most serious environmental contamination so far recorded. We have concentrated on evaluating the outcomes and health risks to women, their reproductive situation, and consequences for their progeny. We have concentrated on two well-defined areas: the Chechersky district of the Gomel region in Belorussia and the Polessky district of the Kiev region in the Ukraine. A number of investigations were carried out on 688 pregnant women and their babies, and data were obtained from 7000 labor histories of the development of newborns for a period of 8 years (3 years before the accident and 5 years after it). Parameters examined included birth rate, thyroid pathology, extragenital pathology such as anemias, renal disorders, hypertension, and abnormalities in the metabolism of fats, complications of gestation, spontaneous abortions, premature deliveries, perinatal morbidity and mortality, stillbirths and early neonatal mortality, infections and inflammatory diseases, neurological symptoms and hemic disturbances in both mothers and infants, trophic anomalies, and biochemical and structural changes in the placenta. Several exogenous, complicating influences were also considered such as psycho-emotional factors, stress, lifestyle changes, and others caused directly by the hazardous situation and by its consequences such as treatment, removal from affected areas, etc. 9 figs.

  16. Water calorimetry-based radiation dosimetry in iridium-192 brachytherapy and proton therapy

    NASA Astrophysics Data System (ADS)

    Sarfehnia, Arman

    The aim of this work is to develop and evaluate a primary standard for HDR 192Ir brachytherapy sources as well as for active spot scanning proton radiotherapy beams based on stagnant 4 °C water calorimetry. The measurements were performed using an in-house built water calorimeter and a parallel-plate calorimeter vessel. The dose measurement results of the McGill calorimeter were validated in high energy photon beams against Canada's national established primary standard at the NRC. The measurements in brachytherapy were performed with a spring-loaded catheter holder which allowed for the 192Ir source to come directly inside the water calorimeter. The COMSOL MULTIPHYSICS(TM) software was used to solve the heat transport equation numerically for a detailed geometrical model of our experimental setup. In brachytherapy, reference dosimetry protocols were also developed and used to measure the dose to water directly using thimble type ionization chambers and Gafchromic films with traceable 60Co (or higher energy photons) calibration factor. Based on water calorimetry standard, we measured an absolute dose rate to water of 361+/-7 microGy/(h·U) at 55 mm source-to-detector separation. The 1.9 % uncertainty on water calorimetry results is in contrast with the current recommended AAPM TG-43 protocol that achieves at best an uncertainty (k=1) of 2.5 % based on an indirect dose to water measurement technique. All measurement results from water calorimetry, ion chamber, film, and TG-43 agreed to within 0.83 %. We achieved an overall dose uncertainty of 0.4 % and 0.6 % for scattered and scanned proton radiation water calorimetry, respectively. The water calorimetry absorbed dose to water results agreed with those obtained through the currently recommended IAEA TRS-398 protocol (measurements made using an ionization chamber with a 60Co calibration factor) to better than 0.14 % and 0.32 % in scattered and scanned proton beams, respectively. In conclusion, this work forms the

  17. Calibration and conformational studies in radiation dosimetry using polymer gel dosimeters

    NASA Astrophysics Data System (ADS)

    Cardenas, Richard L.

    2001-11-01

    The polymer gel dosimeter made its debut in the early 90's and dosimetrists and medical physicists alike were excited about the prospect of using the gel dosimeter as an effective and useful three-dimensional modeling tool. Research in the early to mid-90's brought on better polymer mixtures with greater sensitivity and shelf life. Nearly a decade later, these gels are not being used in a clinical setting. The question is, why are they not being routinely used in the clinical setting for modeling and quality assurance of radiation instrumentation and computer generated treatment plans? There are three main reasons and we address these reasons directly in this investigation. First, every promising experiment performed on these gels were done in ideal conditions. The problem ideal experimentation is that the conditions in a clinical setting are unpredictable hence these idealized protocols could not be easily used in practice. Second, attempts to use the gels in clinical settings had mixed results. There was no real consistency with the results based on calibration curves generated by the gel manufacturer and even based on additional calibration studies performed by the medical physicists. Third, there were no consistent and effective calculation programs that were flexible, rigorous, and consistent to use. Due to these main problems, medical physicists have begun to dismiss the gel dosimeter and reverted to traditional 1-dimensional and 2-dimensional verification methods. What we developed in this study is a means to put the polymer gel dosimeter back into the forefront of dosimetry. First, we performed experiments under a clinical setting. Then, we investigated three different calibration methods, including our very own normalized calibration protocol to identify calibration problems and offer up a solution to this problem. Finally, we also generated a good data processing program that is flexible, rigorous, and consistent to use in any setting. In addition to

  18. Optically stimulated luminescence dosimetry

    NASA Astrophysics Data System (ADS)

    McKeever, Stephen W. S.

    2001-09-01

    Models and the conceptual framework necessary for an understanding of optically stimulated luminescence (OSL) are described. Examples of various OSL readout schemes are described, along with examples of the use of OSL in radiation dosimetry.

  19. Reactor Dosimetry Applications Using RAPTOR-M3G:. a New Parallel 3-D Radiation Transport Code

    NASA Astrophysics Data System (ADS)

    Longoni, Gianluca; Anderson, Stanwood L.

    2009-08-01

    The numerical solution of the Linearized Boltzmann Equation (LBE) via the Discrete Ordinates method (SN) requires extensive computational resources for large 3-D neutron and gamma transport applications due to the concurrent discretization of the angular, spatial, and energy domains. This paper will discuss the development RAPTOR-M3G (RApid Parallel Transport Of Radiation - Multiple 3D Geometries), a new 3-D parallel radiation transport code, and its application to the calculation of ex-vessel neutron dosimetry responses in the cavity of a commercial 2-loop Pressurized Water Reactor (PWR). RAPTOR-M3G is based domain decomposition algorithms, where the spatial and angular domains are allocated and processed on multi-processor computer architectures. As compared to traditional single-processor applications, this approach reduces the computational load as well as the memory requirement per processor, yielding an efficient solution methodology for large 3-D problems. Measured neutron dosimetry responses in the reactor cavity air gap will be compared to the RAPTOR-M3G predictions. This paper is organized as follows: Section 1 discusses the RAPTOR-M3G methodology; Section 2 describes the 2-loop PWR model and the numerical results obtained. Section 3 addresses the parallel performance of the code, and Section 4 concludes this paper with final remarks and future work.

  20. Thermoluminescence in medical dosimetry.

    PubMed

    Rivera, T

    2012-12-01

    Thermoluminescence dosimetry (TLD) is applied worldwide for personal and medical dosimetry. TLD method has resulted in many interesting findings in medicine as TL dosimeters have many relevant advantages such as high sensitivity, small physical size, tissue equivalence, etc. The main characteristics of various TL materials used in radiation measurements and their practical consequences are overviewed: well defined TL glow curve, batch homogeneity, signal stability after irradiation, precision and accuracy, response with dose, and influence of energy. In this paper a brief summary of the advances in the application of thermally stimulated luminescence (TSL) to dosimetry in radiation therapy application is presented.

  1. [Iodine 131: biokinetics, radiation exposure and risk assessment with reference to the reactor accident at Chernobyl].

    PubMed

    Moser, E; Roedler, H D

    1987-06-01

    Following the reactor accident at Chernobyl, this paper describes the biokinetics of radioiodine in man and discusses the radiation exposure resulting from intake of 131I. The risk of radiation-induced thyroid carcinomas and of congenital abnormalities is evaluated. Assuming a linear dose/risk relationship, one can calculate an increase in mortality from thyroid carcinomas amongst children in southern Germany of 100 to 101 per million children. For adults in southern Germany, and for the rest of the population in Germany, the figure is considerably lower. Gonadal dose from the 131I released is so small, compared with the annual natural radiation exposure, that it is not appropriate to discuss genetic effects.

  2. [A questionnaire survey about public's image of radiation after the Fukushima Daiichi nuclear power plant accident].

    PubMed

    Okazaki, Ryuji; Ootsuyama, Akira; Abe, Toshiaki; Kuto, Tatsuhiko

    2012-03-01

    A questionnaire survey about the public's image of radiation was performed after the Fukushima Daiichi nuclear power plant (FDNPP) accident. The survey was taken by general citizens (200 and 1640 in Fukushima and 52 outside of Fukushima) and doctors (63 in Fukushima and 1942 outside of Fukushima (53 in Oita, 44 in Sagamihara and 1,845 in Kitakyushu)) in and outside of Fukushima and second year medical students in the University of Occupational and Environmental Health, Japan. The questionnaire surveys were performed during lectures about radiation. The response rates were 86% for the general citizens in Fukushima, 91% for the general citizens outside of Fukushima, 86% for doctors in Fukushima, and 85% and 86% for doctors in Sagamihara and Oita, respectively. The questionnaire surveys were sent to clinics and hospitals in Fukushima where the general citizens answered with a response rate of 50%. When the questionnaire surveys were sent to clinics and hospitals in Kitakyushu, doctors answered, with a response rate of 17%. The percentages of anxiety about future radiation effects after the FDNPP accident were the highest among the general citizens (71.6% in Fukushima and 40.4% outside of Fukushima), in the middle among the doctors (30.2% in Fukushima and 26.2% outside of Fukushima) and the lowest among the medical students (12.2%). The doctors in Fukushima and the medical students were anxious about food and soil pollution. The general citizens and the doctors outside of Fukushima were anxious about health problems and food and soil pollution. We concluded that a high level of education about radiation decreased the anxiety about the radiation effects. It is important to spread knowledge about radiation.

  3. Radiation situation in Kamchatka after the Fukushima nuclear power station accident

    NASA Astrophysics Data System (ADS)

    Sidorin, A. I.

    2013-12-01

    The chronology of events in Kamchatka related to the threat of radioactive contamination of the territory as a result of the Fukushima-1 nuclear power station (NPS) accident in Japan is briefly reviewed based on the published data. The accident happened on March 11, 2011, after a strong earthquake near the coast of Japan and the giant tsunami followed by the earthquake. The power supply was damaged and, as a result, the cooling system of NPS reactors was destroyed. Although the reactors did not explode, radioactive emissions from the damaged NPS discharged into the atmosphere and spread over large areas by the air flows. Information about the radiation situation in Kamchatka is controversial. Therefore, the author carried out regular monitoring of the radiation background during a hiking trip in Kamchatka in August 2011. The data are presented in this paper. It was concluded that the radiation background along the route of the trip was consistent (within the accuracy of measurement methods) with the normal values of a natural background. A thorough analysis of air, soil, food samples, etc., is required for a more detailed study to identify the presence of radionuclides in the atmospheric emissions from the damaged NPS in Japan.

  4. [The cradle of the Russian radioecology (to the 50th anniversary of the Kyshtym radiation accident)].

    PubMed

    Aleksakhin, R M; Prister, B S

    2008-01-01

    On September 29, 1957, at a nuclear industry facility (Production Association "Mayak"), there was a large radiation accident resulting in the release of radioactive wastes into the environment and the formation of the East-Urals Radioactive Trail (EURT). Within the EURT and there established in 1958 an Experimental Scientific Research Station (ESRS) which came to be known as alma mater of domestic radioecology, various comprehensive long-term investigations had been carried out. The main results of these 50-year investigations have been summarized for a broad range of problems on radionuclide migration in the natural environment and ionizing radiation effects on biota, as well as problems of environmental protection. In addition to the studies of the in situ behavior of released during the accident anthropogenic radionuclides (primarily 90Sr, the main dose-forming radionuclide within the EURT), at the ESRS large experiment have been performed to study migration and biological effects on agricultural plants and animals of man-made radionuclides (especially fresh mixtures of fission products) introduced to the natural environment. Results of ESRS experiments are described on irradiation of natural biogeocenoses from a powerful source of ionizing radiation (1.2 x 10(15) Bq 137Cs). The first unique experience is described of remediation of radioactively contaminated areas with emphasis on agricultural radioecology. The importance of the EURT and ESRS radioecological studies for the development of radioecology as a science is stressed. PMID:18666658

  5. EURADOS INTERCOMPARISONS IN EXTERNAL RADIATION DOSIMETRY: SIMILARITIES AND DIFFERENCES AMONG EXERCISES FOR WHOLE-BODY PHOTON, WHOLE-BODY NEUTRON, EXTREMITY, EYE-LENS AND PASSIVE AREA DOSEMETERS.

    PubMed

    Romero, Ana M; Grimbergen, Tom; McWhan, Andrew; Stadtmann, Hannes; Fantuzzi, Elena; Clairand, Isabelle; Neumaier, Stefan; Figel, Markus; Dombrowski, Harald

    2016-09-01

    The European Radiation Dosimetry Group (EURADOS) has been organising dosimetry intercomparisons for many years in response to an identified requirement from individual monitoring services (IMS) for independent performance tests for dosimetry systems. The participation in intercomparisons gives IMS the opportunity to show compliance with their own quality management system, compare results with other participants and develop plans for improving their dosimetry systems. In response to growing demand, EURADOS has increased the number of intercomparisons for external radiation dosimetry. Most of these fit into the programme of self-financing intercomparisons for dosemeters routinely used by IMS. This programme is being coordinated by EURADOS working group 2 (WG2). Up to now, this programme has included four intercomparisons for whole-body dosemeters in photon fields, one for extremity dosemeters in photon and beta fields, and one for whole-body dosemeters in neutron fields. Other EURADOS working groups have organised additional intercomparisons including events in 2014 for eye-lens dosemeters and passive area dosemeters for environmental monitoring. In this paper, the organisation and achievements of these intercomparisons are compared in detail focusing on the similarities and differences in their execution. PMID:26759475

  6. Public meetings on radiation and its health effects caused by the Fukushima nuclear accident

    SciTech Connect

    Sugiyama, K.; Ayame, J.; Takashita, H.; Yamamoto, R.

    2013-07-01

    The Japan Atomic Energy Agency (JAEA) has held public meetings on radiation and its health effects mainly for parents of students in kindergartens, elementary schools, and junior high schools in Fukushima and Ibaraki prefectures after the Fukushima nuclear accident. These meetings are held based on our experience of practicing risk communication activities for a decade in JAEA with local residents. By analyzing questionnaires collected after the meetings, we confirmed that interactive communication is effective in increasing participants' understanding and in decreasing their anxiety. Most of the participants answered that they understood the contents and that it eased their mind. (authors)

  7. Application of the planar-scanning technique to the near-field dosimetry of millimeter-wave radiators.

    PubMed

    Zhao, Jianxun; Lu, Hongmin; Deng, Jun

    2015-02-01

    The planar-scanning technique was applied to the experimental measurement of the electric field and power flux density (PFD) in the exposure area close to the millimeter-wave (MMW) radiator. In the near-field region, the field and PFD were calculated from the plane-wave spectrum of the field sampled on a scan plane far from the radiator. The measurement resolution was improved by reducing the spatial interval between the field samples to a fraction of half the wavelength and implementing multiple iterations of the fast Fourier transform. With the reference to the results from the numerical calculation, an experimental evaluation of the planar-scanning measurement was made for a 50 GHz radiator. Placing the probe 1 to 3 wavelengths from the aperture of the radiator, the direct measurement gave the near-field data with significant differences from the numerical results. The planar-scanning measurement placed the probe 9 wavelengths away from the aperture and effectively reduced the maximum and averaged differences in the near-field data by 70.6% and 65.5%, respectively. Applied to the dosimetry of an open-ended waveguide and a choke ring antenna for 60 GHz exposure, the technique proved useful to the measurement of the PFD in the near-field exposure area of MMW radiators.

  8. Dosimetry at the Los Alamos Critical Experiments Facility: Past, present, and future

    SciTech Connect

    Malenfant, R.E.

    1993-10-01

    Although the primary reason for the existence of the Los Alamos Critical Experiments Facility is to provide basic data on the physics of systems of fissile material, the physical arrangements and ability to provide sources of radiation have led to applications for all types of radiation dosimetry. In the broad definition of radiation phenomena, the facility has provided sources to evaluate biological effects, radiation shielding and transport, and measurements of basic parameters such as the evaluation of delayed neutron parameters. Within the last 15 years, many of the radiation measurements have been directed to calibration and intercomparison of dosimetry related to nuclear criticality safety. Future plans include (1) the new applications of Godiva IV, a bare-metal pulse assembly, for dosimetry (including an evaluation of neutron and gamma-ray room return); (2) a proposal to relocate the Health Physics Research Reactor from the Oak Ridge National Laboratory to Los Alamos, which will provide the opportunity to continue the application of a primary benchmark source to radiation dosimetry; and (3) a proposal to employ SHEBA, a low-enrichment solution assembly, for accident dosimetry and evaluation.

  9. Germanium-doped optical fiber for real-time radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Mizanur Rahman, A. K. M.; Zubair, H. T.; Begum, Mahfuza; Abdul-Rashid, H. A.; Yusoff, Z.; Ung, N. M.; Mat-Sharif, K. A.; Wan Abdullah, W. S.; Amouzad Mahdiraji, Ghafour; Amin, Y. M.; Maah, M. J.; Bradley, D. A.

    2015-11-01

    Over the past three decades growing demand for individualized in vivo dosimetry and subsequent dose verification has led to the pursuit of newer, novel and economically feasible materials for dosimeters. These materials are to facilitate features such as real-time sensing and fast readouts. In this paper, purposely composed SiO2:Ge optical fiber is presented as a suitable candidate for dosimetry. The optical fiber is meant to take advantage of the RL/OSL technique, providing both online remote monitoring of dose rate, and fast readouts for absorbed dose. A laboratory-assembled OSL reader has been used to acquire the RL/OSL response to LINAC irradiations (6 MV photons). The notable RL characteristics observed include constant level of luminescence for the same dose rate (providing better consistency compared to TLD-500), and linearity of response in the radiotherapy range (1 Gy/min to 6 Gy/min). The OSL curve was found to conform to an exponential decay characteristic (illumination with low LED source). The Ge doping resulted in an effective atomic number, Zeff, of 13.5 (within the bone equivalent range). The SiO2:Ge optical fiber sensor, with efficient coupling, can be a viable solution for in vivo dosimetry, besides a broad range of applications.

  10. Biodistribution and Radiation Dosimetry for a Probe Targeting Prostate-Specific Membrane Antigen for Imaging and Therapy

    PubMed Central

    Herrmann, Ken; Bluemel, Christina; Weineisen, Martina; Schottelius, Margret; Wester, Hans-Jürgen; Czernin, Johannes; Eberlein, Uta; Beykan, Seval; Lapa, Constantin; Riedmiller, Hubertus; Krebs, Markus; Kropf, Saskia; Schirbel, Andreas; Buck, Andreas K.; Lassmann, Michael

    2016-01-01

    Prostate-specific membrane antigen (PSMA) is a promising target for diagnosis and treatment of prostate cancer. EuK-Subkff-68Ga-DOTAGA (68Ga-PSMA Imaging & Therapy [PSMA I&T]) is a recently introduced PET tracer for imaging PSMA expression in vivo. Whole-body distribution and radiation dosimetry of this new probe were evaluated. Methods Five patients with a history of prostate cancer were injected intravenously with 91–148 MBq of 68Ga-PSMA I&T (mean ± SD, 128 ± 23 MBq). After an initial series of rapid whole-body scans, 3 static whole-body scans were acquired at 1, 2, and 4 h after tracer injection. Time-dependent changes of the injected activity per organ were determined. Mean organ-absorbed doses and effective doses were calculated using OLINDA/EXM. Results Injection of 150 MBq of 68Ga-PSMA I&T resulted in an effective dose of 3.0 mSv. The kidneys were the critical organ (33 mGy), followed by the urinary bladder wall and spleen (10 mGy each), salivary glands (9 mGy each), and liver (7 mGy). Conclusion 68Ga-PSMA I&T exhibits a favorable dosimetry, delivering organ doses that are comparable to (kidneys) or lower than those delivered by 18F-FDG. PMID:25883128

  11. Improved radiation dosimetry/risk estimates to facilitate environmental management of plutonium contaminated sites. 1998 annual progress report

    SciTech Connect

    Scott, B.R.

    1998-06-01

    'The objective of this research is to evaluate distributions of possible alpha radiation doses to the lung, bone, and liver and associated health-risk distributions for plutonium (Pu) inhalation-exposure scenarios relevant to environmental management of PuO{sub 2}-contaminated sites. Currently available dosimetry/risk models do not apply to exposure scenarios where, at most, a small number of highly radioactive PuO{sub 2} particles are inhaled (stochastic exposure [SE] paradigm). For the SE paradigm, risk distributions are more relevant than point estimates of risk. The focus of the research is on the SE paradigm and on high specific activity, alpha-emitting (HSA-aE) particles such as 238 PuO{sub 2} . The scientific goal is to develop a stochastic respiratory tract dosimetry/risk computer model for evaluating the desired absorbed dose distributions and associated health-risk distributions, for Department of Energy (DOE) workers and members of the public. This report summarizes results after 1 year of a 2-year project.'

  12. Operational accidents and radiation exposures at ERDA facilities, 1975-1977

    SciTech Connect

    Not Available

    1980-05-01

    The Energy Research and Development Administration (ERDA) accident frequency and losses were similar to that of the Atomic Energy Commission (AEC) from 1970 through 1974. The ERDA incidence rates per 200,000 work hours were 1.05 for lost workday injuries and 17.8 for workdays lost. These rates are about one-third of the national industrial averages reported by the National Safety Council (NSC). Ten fatalities occurred at ERDA facilities resulting in an average annual rate of three deaths per 100,000 workers compared to the national rate of 14 deaths per 100,000 workers. ERDA's total property loss from 1975 to 1977 was $11.9 million; $1.8 million caused by fires. The average annual loss rates, in cents loss per $100 valuation, were 1.15 for non-fire and 0.18 for fire. These rates are higher than the AEC post; Rocky Flats period (1970 through 1974) which were 0.60 non-fire and 0.10 fire; but are lower than the average annual rates which were 2.4 non-fire and 1.7 fire for the entire history of the AEC. Accidents causing more than $50,000 in property damage are tabulated. ERDA continued to make a strong effort to eliminate unnecessary radiation exposure to workers. The number of employees exceeding 1 rem decreased from 2999 in 1975 to 2274 in 1977. The two appendixes include criteria for accident investigations and summaries of accident investigation reports.

  13. A Device for Search of Gamma-Radiation Intensive Sources at the Radiation Accident Condition

    SciTech Connect

    Batiy, Valeriy; Klyuchnykov, A; Kochnev, N; Rudko, Vladimir; shcherbin, vladimir; Yegorov, V; Schmieman, Eric A.

    2005-08-08

    The procedure designed for measuring angular distributions of gamma radiation and for search of gamma radiation intensive sources is described. It is based on application of the original multidetector device ShD-1, for measuring an angular distribution in a complete solid angle (4 pi). The calibration results and data on the angular distributions of intensity of gamma radiation at the roof of Chornobyl NPP ''Shelter'' are presented.

  14. Operation Upshot-Knothole. Project 29. 1. Comparison and evaluation of dosimetry methods applicable to gamma radiation, Nevada Proving Ground. Report for March-June 1953

    SciTech Connect

    Taplin, G.V.; Sigoloff, S.C.; Douglas, C.H.; Paglia, D.E.; Heller, C.J.

    1984-10-31

    The three major objectives and parts of this project were to compare and evaluate the accuracy and practicality of chemical vs film and other methods of gamma dosimetry for radiations encountered under bomb conditions at sites receiving (1) either prompt- or residual-gamma exposures or mixtures of both, (2) only residualgamma radiations, either neutron induced or from fission-product fallout, and (3) mixed neutron-gamma irradiation plus correlation with biological effects.

  15. Operational accidents and radiation exposures at DOE facilities. Fiscal year 1979

    SciTech Connect

    1980-12-01

    The Department of Energy's safety performance in fiscal year 1979 showed improvement in all categories over fiscal year 1978. The loss rates were less than one-half the United States industry average as reported by the National Safety Council. Incidence rates per 200,000 workhours were 1.1 lost workday cases and 17.2 lost workdays compared to 1.2 lost workday cases and 17.6 lost workdays during fiscal year 1978. The recordable occupational illness rate, based on only 80 cases, was 0.06 cases per 200,000 workhours compared to 0.07 cases per 200,000 workhours for fiscal year 1978. Nine fatalities of contractor employees resulted in an annual rate of 6.0 deaths per 100,000 workers compared with 10 fatalities during fiscal year 1978, and an annual rate of 6.7 deaths per 100,000 workers. The total Department of Energy property loss reported during fiscal year 1979 was $3.3 million; $765,400 was caused by fire, and $2.5 million by other causes. A total of 121 million vehicle miles of official travel resulted in 685 accidents with $338,400 in property damage. The loss rates of 5.7 accidents per million vehicle miles and $2.80 per 1000 miles were improvements over the fiscal year 1978 rates of 5.8 accidents per million vehicle miles and $2.97 property damage per 1000 miles. The 104,986 monitored Department of Energy and its contractor employees received a total dose of 9040 rem in calendar year 1979. Both the total dose and the 1748 employees receiving radiation exposures greater than 1 rem in 1979 represent a continuing downward trend from the calendar year 1978 total dose of 9380 rem and the 1826 employees who received radiation exposures greater than 1 rem.

  16. Historical review of personnel dosimetry development and its use in radiation protection programs at Hanford 1944 to the 1980s

    SciTech Connect

    Wilson, R.H.

    1987-02-01

    This document is an account of the personnel dosimetry programs as they were developed and practiced at Hanford from their inception in 1943 to 1944 to the 1980s. This history is divided into sections covering the general categories of external and internal measurement methods, in vivo counting, radiation exposure recordkeeping, and calibration of personnel dosimeters. The reasons and circumstances surrounding the inception of these programs at Hanford are discussed. Information about these programs was obtained from documents, letters, and memos that are available in our historical records; the personnel files of many people who participated in these programs; and from the recollections of many long-time, current, and past Hanford employees. For the most part, the history of these programs is presented chronologically to relate their development and use in routine Hanford operations. 131 refs., 38 figs., 23 tabs.

  17. A review of the use and potential of the GATE Monte Carlo simulation code for radiation therapy and dosimetry applications

    SciTech Connect

    Sarrut, David; Bardiès, Manuel; Marcatili, Sara; Mauxion, Thibault; Boussion, Nicolas; Freud, Nicolas; Létang, Jean-Michel; Jan, Sébastien; Maigne, Lydia; Perrot, Yann; Pietrzyk, Uwe; Robert, Charlotte; and others

    2014-06-15

    In this paper, the authors' review the applicability of the open-source GATE Monte Carlo simulation platform based on the GEANT4 toolkit for radiation therapy and dosimetry applications. The many applications of GATE for state-of-the-art radiotherapy simulations are described including external beam radiotherapy, brachytherapy, intraoperative radiotherapy, hadrontherapy, molecular radiotherapy, and in vivo dose monitoring. Investigations that have been performed using GEANT4 only are also mentioned to illustrate the potential of GATE. The very practical feature of GATE making it easy to model both a treatment and an imaging acquisition within the same frameworkis emphasized. The computational times associated with several applications are provided to illustrate the practical feasibility of the simulations using current computing facilities.

  18. Development of europium doped BaSO{sub 4} TL OSL dual phosphor for radiation dosimetry applications

    SciTech Connect

    Patle, Anita Patil, R. R.; Kulkarni, M. S.; Bhatt, B. C.

    2015-08-28

    This paper presents the results on the preparation and characterization of Europium-doped Barium sulfate (BaSO{sub 4}: Eu) TL /OSL dual phosphor. The OSL sensitivity was found to be 11% of the commercially available Al{sub 2}O{sub 3}: C, using area integration method. The sample also shows good TL sensitivity and the dosimetric peak appears around 190°C with a shoulder at 282°C. After OSL readout, No change in the TL glow curve is observed. Since the observed TL peaks are not responsible for the observed OSL, good OSL as well as TL sensitivity and low fading will make this phosphor suitable for applications in radiation dosimetry using OSL as well as TL.

  19. An Absorbed-Dose/Dose-Rate Dependence for the Alanine-EPR Dosimetry System and Its Implications in High-Dose Ionizing Radiation Metrology

    PubMed Central

    Desrosiers, M. F.; Puhl, J. M.; Cooper, S. L.

    2008-01-01

    NIST developed the alanine dosimetry system in the early 1990s to replace radiochromic dye film dosimeters. Later in the decade the alanine system was firmly established as a transfer service for high-dose radiation dosimetry and an integral part of the internal calibration scheme supporting these services. Over the course of the last decade, routine monitoring of the system revealed a small but significant observation that, after examination, led to the characterization of a previously unknown absorbed-dose-dependent, dose-rate effect for the alanine system. Though the potential impact of this effect is anticipated to be extremely limited for NIST’s customer-based transfer dosimetry service, much greater implications may be realized for international measurement comparisons between National Measurement Institutes. PMID:27096113

  20. Contamination and radiation exposure in central Europe after the Chernobyl accident

    SciTech Connect

    Bayer, A.; Mueck, K.; Loosli, H.H.

    1996-06-01

    Ten years ago, on 26 April 1986, as a consequence of an accident in Unit 4 of the Chernobyl-NPP, a large quantity of radioactive material was released into the atmosphere for some days. This material was spread over wide areas of Europe. Due to variable weather conditions the activity concentrations in air varied considerably in different regions. Also as a consequence of large variations in precipitation intensity-particularly in the regions of Southeastern Germany, Austria and Southern Switzerland-up to 100 kBq m{sup -2} {sup 137}Cs were deposited on the soil. Due to fallout, washout, and/or rainout, a range of foodstuffs were contaminated, and foodstuffs directly exposed to the fallout [vegetables and green fodder (grass)] showed the highest contamination levels. Consequently, milk also showed a significantly increased activity concentration, in particular of {sup 131}I. In the following years contamination in all kinds of foodstuffs decreased, but elevated contamination levels in special pathways like venison and mushrooms are still observed to date. This contamination resulted in additional exposure, mainly due to external radiation from ground and from consumption of contaminated food. The radiation exposure in the most contaminated areas was calculated on the basis of model assumptions and was found to be about 1 mSv during the first year after the accident. Using this model, the ingestion pathway was overestimated by at least a factor of two. This additional exposure decreased and is now less than 1 % on average; in the most contaminated areas, this is a few percent of the average natural radiation exposure.

  1. Automated DICOM metadata and volumetric anatomical information extraction for radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Papamichail, D.; Ploussi, A.; Kordolaimi, S.; Karavasilis, E.; Papadimitroulas, P.; Syrgiamiotis, V.; Efstathopoulos, E.

    2015-09-01

    Patient-specific dosimetry calculations based on simulation techniques have as a prerequisite the modeling of the modality system and the creation of voxelized phantoms. This procedure requires the knowledge of scanning parameters and patients’ information included in a DICOM file as well as image segmentation. However, the extraction of this information is complicated and time-consuming. The objective of this study was to develop a simple graphical user interface (GUI) to (i) automatically extract metadata from every slice image of a DICOM file in a single query and (ii) interactively specify the regions of interest (ROI) without explicit access to the radiology information system. The user-friendly application developed in Matlab environment. The user can select a series of DICOM files and manage their text and graphical data. The metadata are automatically formatted and presented to the user as a Microsoft Excel file. The volumetric maps are formed by interactively specifying the ROIs and by assigning a specific value in every ROI. The result is stored in DICOM format, for data and trend analysis. The developed GUI is easy, fast and and constitutes a very useful tool for individualized dosimetry. One of the future goals is to incorporate a remote access to a PACS server functionality.

  2. Daily variation of radiation dose rate after the Fukushima Nuclear Accident

    NASA Astrophysics Data System (ADS)

    Yamauchi, Masatoshi

    2015-04-01

    After the radioactive contamination of the lands from the Fukushima Nuclear Power Plant accident, the radiation dose rates observed by the dosimeters often shows daily variations, at different local times at different places or time. These variations are caused by different reasons: the temperature-dependent characteristics of the dosimeter (instrumental effect), the daily convective wind that lifts up the radioactive small particle on the ground (local effect), and the daily sea-land wind that transports the radioactive small particle from highly contaminated area (regional effect). The last type is most important in understanding the internal dose by air taking. However, while very regular patterns can easily be judged as instrumental effect, variations that strongly depend on the weather conditions are not easily judged. Combining the atmospheric electric field measurement near the ground (potential gradient, PG) with the wind and weather data, some of these unclear cases can be classified into above three reasoning, which will be shown in the presentation. Thus, the PG measurement is important right after any nuclear accidents in the future.

  3. A Novel Technique for Performing Space Based Radiation Dosimetry Using DNA: Results from GRaDEx-I and the Design of GRaDEx-II

    NASA Technical Reports Server (NTRS)

    Ritter, Joe; Branly, R.; Theodorakis, C.; Bickham, J.; Swartz, C.; Friedfeld, R.; Ackerman, E.; Carruthers, C.; DiGirolamo, A.; Faranda, J.; Howard, E.; Bruno, C.

    1999-01-01

    Because of the large amounts of cosmic radiation in the space environment relative to that on earth, the effects of radiation on the physiology of astronauts is of major concern. Doses of radiation which can cause acute or chronic biological effects are to be avoided, therefore determination of the amount of radiation exposure encountered during space flight and assessment of its impact on biological systems is critical. Quantifying the radiation dosage and damage to biological systems, especially to humans during repetitive high altitude flight and during long duration space flight is important for several reasons. Radiation can cause altered biosynthesis and long term genotoxicity resulting in cancer and birth defects, etc. Radiation damage to biological systems depends in a complex way on incident radiation species and their energy spectra. Typically non-biological, i.e. film or electronic monitoring systems with narrow energy band sensitivity are used to perform dosimetry and then results are extrapolated to biological models. For this reason it may be desirable to perform radiation dosimetry by using biological molecules e.g. DNA or RNA strands as passive sensors. A lightweight genotoxicology experiment was constructed to determine the degree to which in-vitro naked DNA extracted from tissues of a variety of vertebrate organisms is damaged by exposure to radiation in a space environment. The DNA is assayed by means of agarose gel electrophoresis to determine damage such as strand breakage caused by high momentum particles and photons, and base oxidation caused by free radicals. The length distribution of DNA fragments is directly correlated with the radiation dose. It is hoped that a low mass, low cost, passive biological system to determine dose-response relationship (increase in strand breaks with increase in exposure) can be developed to perform radiation dosimetry in support of long duration space flight, and to predict negative effects on biological

  4. A Novel Technique for Performing Space Based Radiation Dosimetry Using DNA-Results from GRaDEx-I and the Design of GRaDEx-II

    NASA Technical Reports Server (NTRS)

    Ritter, Joe; Branly, R.; Theodorakis, C.; Bickham, J.; Swartz, C.; Friedfeld, R.; Ackerman, E.; Carruthers, C.; DiGirolamo, A.; Faranda, J.

    1999-01-01

    Because of the large amounts of cosmic radiation in the space environment relative to that on earth, the effects of radiation on the physiology of astronauts is of major concern. Doses of radiation which can cause acute or chronic biological effects are to be avoided, therefore determination of the amount of radiation exposure encountered during space flight and assessment of its impact on biological systems is critical. Quantifying the radiation dosage and damage to biological systems, especially to humans during repetitive high altitude flight and during long duration space flight is important for several reasons. Radiation can cause altered biosynthesis and long term genotoxicity resulting in cancer and birth defects etc. Radiation damage to biological systems depends in a complex way on incident radiation species and their energy spectra. Typically non-biological, i.e. film or electronic monitoring systems with narrow energy band sensitivity are used to perform dosimetry and then results are extrapolated to biological models. For this reason it may be desirable to perform radiation dosimetry by using biological molecules e.g. DNA or RNA strands as passive sensors. A lightweight genotoxicology experiment was constructed to determine the degree to which in vitro naked DNA extracted from tissues of a variety of vertebrate organisms is damaged by exposure to radiation in a space environment. The DNA is assayed by means of agarose gel electrophoresis to determine damage such as strand breakage caused by high momentum particles and photons, and base oxidation caused by free radicals. The length distribution of DNA fragments is directly correlated with the radiation dose. It is hoped that a low mass, low cost, passive biological system to determine dose response relationship (increase in strand breaks with increase in exposure) can be developed to perform radiation dosimetry in support of long duration space flight, and to predict negative effects on biological

  5. Results from 2010 Caliban Criticality Dosimetry Intercomparison

    SciTech Connect

    Veinot, K. G.

    2011-10-12

    The external dosimetry program participated in a criticality dosimetry intercomparison conducted at the Caliban facility in Valduc, France in 2010. Representatives from the dosimetry and instrumentation groups were present during testing which included irradiations of whole-body beta/gamma (HBGT) and neutron thermoluminescent dosimeters (TLDs), a fixed nuclear accident dosimeter (FNAD), electronic alarming dosimeters, and a humanoid phantom filled with reference man concentrations of sodium. This report reviews the testing procedures, preparations, irradiations, and presents results of the tests.

  6. Longitudinal neurocognitive assessments of Ukrainians exposed to ionizing radiation after the Chernobyl nuclear accident.

    PubMed

    Gamache, Gerald L; Levinson, Daniel M; Reeves, Dennis L; Bidyuk, Peter I; Brantley, Kimberly K

    2005-01-01

    A 4-year longitudinal study of the cognitive effects of the Chernobyl nuclear accident was conducted from 1995 to 1998. The controls were healthy Ukrainians residing several hundred kilometers away from Chernobyl. The exposed groups included Eliminators, Forestry workers and Agricultural workers living within 150 km of Chernobyl. Accuracy and efficiency of cognitive performance were assessed using ANAMUKR, a specialized subset of the Automated Neuropsychological Assessment Metrics (ANAM) battery of tests. Analyses of variance, followed by appropriate pairwise comparisons, indicated that the 4-year averaged levels of performance of the exposure groups (especially the Eliminators) were significantly lower than those of the controls on most measures; further, analyses of performance across time revealed significant declines in accuracy and efficiency, as well as psychomotor slowing, for all exposed groups over the 4-year period. These findings strongly indicate impairment of brain function resulting from both acute and chronic exposure to ionizing radiation.

  7. Health effects of radiation and other health problems in the aftermath of nuclear accidents, with an emphasis on Fukushima.

    PubMed

    Hasegawa, Arifumi; Tanigawa, Koichi; Ohtsuru, Akira; Yabe, Hirooki; Maeda, Masaharu; Shigemura, Jun; Ohira, Tetsuya; Tominaga, Takako; Akashi, Makoto; Hirohashi, Nobuyuki; Ishikawa, Tetsuo; Kamiya, Kenji; Shibuya, Kenji; Yamashita, Shunichi; Chhem, Rethy K

    2015-08-01

    437 nuclear power plants are in operation at present around the world to meet increasing energy demands. Unfortunately, five major nuclear accidents have occurred in the past--ie, at Kyshtym (Russia [then USSR], 1957), Windscale Piles (UK, 1957), Three Mile Island (USA, 1979), Chernobyl (Ukraine [then USSR], 1986), and Fukushima (Japan, 2011). The effects of these accidents on individuals and societies are diverse and enduring. Accumulated evidence about radiation health effects on atomic bomb survivors and other radiation-exposed people has formed the basis for national and international regulations about radiation protection. However, past experiences suggest that common issues were not necessarily physical health problems directly attributable to radiation exposure, but rather psychological and social effects. Additionally, evacuation and long-term displacement created severe health-care problems for the most vulnerable people, such as hospital inpatients and elderly people.

  8. Health effects of radiation and other health problems in the aftermath of nuclear accidents, with an emphasis on Fukushima.

    PubMed

    Hasegawa, Arifumi; Tanigawa, Koichi; Ohtsuru, Akira; Yabe, Hirooki; Maeda, Masaharu; Shigemura, Jun; Ohira, Tetsuya; Tominaga, Takako; Akashi, Makoto; Hirohashi, Nobuyuki; Ishikawa, Tetsuo; Kamiya, Kenji; Shibuya, Kenji; Yamashita, Shunichi; Chhem, Rethy K

    2015-08-01

    437 nuclear power plants are in operation at present around the world to meet increasing energy demands. Unfortunately, five major nuclear accidents have occurred in the past--ie, at Kyshtym (Russia [then USSR], 1957), Windscale Piles (UK, 1957), Three Mile Island (USA, 1979), Chernobyl (Ukraine [then USSR], 1986), and Fukushima (Japan, 2011). The effects of these accidents on individuals and societies are diverse and enduring. Accumulated evidence about radiation health effects on atomic bomb survivors and other radiation-exposed people has formed the basis for national and international regulations about radiation protection. However, past experiences suggest that common issues were not necessarily physical health problems directly attributable to radiation exposure, but rather psychological and social effects. Additionally, evacuation and long-term displacement created severe health-care problems for the most vulnerable people, such as hospital inpatients and elderly people. PMID:26251393

  9. [Somatic chromosome mutagenesis in residents of Ukraine exposed to ionizing radiation in different periods after the Chernobyl accident].

    PubMed

    Pilinskaia, M A; Dybskiĭ, S S; Shemetun, E V; Dybskaia, E B

    2011-01-01

    The authors summarize results of 25-year selective cytogenetic monitoring of the priority groups in different periods after the Chernobyl accident. The increase in intensity of somatic chromosome mutagenesis in exposed individuals as a result of both targeted and non-targeted radiation-induced cytogenetic effects has been confirmed including delayed, transmissible, hidden chromosome instability and the bystander effect.

  10. Forecasting Radiation Effects on Wildlife in Japan After the Fukushima Nuclear Accident, Based on Limited Information of Post-Accident Early Stage in 2011

    NASA Astrophysics Data System (ADS)

    Saito, M. U.; Doko, T.; Koike, F.

    2014-11-01

    Due to the 11 March 2011 Tohoku earthquake, massive radioactive materials were released from the Fukushima Daiichi Nuclear Power Plant (Fukushima NPP). It is crucial to predict the regional distribution and magnitude of the effects on wildlife by radioactive materials. However, during the post-accident early stage in 2011, limited information on large-scale pollution and prediction maps was open to public. Hence, this paper aimed to provide (1) the pollution map covering areas within 300 km from the Fukushima NPP where the radiation intensity exceeded 0.5 μSv/h, (2) pollution maps which predicted air dose for the next 30 years after the accident, and (3) maps of areas where wildlife might be affected by radioactive isotopes by the Fukushima nuclear accident. First, the relative contributions of 131I, 134Cs, and 137Cs were estimated from time series observation data. Second, a 30-year prediction of the pollution was calculated based on the isotope half-lives. Third, the chronic radiation effects on vertebrates were estimated using the threshold dose rate proposed by Sazykina et al. (2009). We examined the chronic radiation effects on morbidity, reproduction, and longevity. The results indicated that radioactive materials could have affected vertebrate morbidity within a 350 km2 area in early April 2011; the threshold level was the median result of Sazykina et al. (2009) with bootstrapping. Based on the prediction, a 15.5 km2 region will remain affected after 30 years. These areas should be monitored to confirm the effects of radioactivity on wildlife.

  11. Bipolarization of Risk Perception about the Health Effects of Radiation in Residents after the Accident at Fukushima Nuclear Power Plant.

    PubMed

    Orita, Makiko; Hayashida, Naomi; Nakayama, Yumi; Shinkawa, Tetsuko; Urata, Hideko; Fukushima, Yoshiko; Endo, Yuuko; Yamashita, Shunichi; Takamura, Noboru

    2015-01-01

    The late health effects of low-dose rate radiation exposure are still a serious public concern in the Fukushima area even four years after the accident at Fukushima Daiichi Nuclear Power Plant (FNPP). To clarify the factors associated with residents' risk perception of radiation exposure and consequent health effects, we conducted a survey among residents of Kawauchi village in May and June 2014, which is located within 30 km of FNPP. 85 of 285 residents (29.8%) answered that acute radiation syndrome might develop in residents after the accident, 154 (54.0%) residents responded that they had anxieties about the health effects of radiation on children, and 140 (49.1%) residents indicated that they had anxieties about the health effects of radiation on offspring. Furthermore, 107 (37.5%) residents answered that they had concerns about health effects that would appear in the general population simply by living in an environment with a 0.23 μSv per hour ambient dose for one year, 149 (52.2%) residents reported that they were reluctant to eat locally produced foods, and 164 (57.5%) residents believed that adverse health effects would occur in the general population by eating 100 Bq per kg of mushrooms every day for one year. The present study shows that a marked bipolarization of the risk perception about the health effects of radiation among residents could have a major impact on social well-being after the accident at FNPP.

  12. Bipolarization of Risk Perception about the Health Effects of Radiation in Residents after the Accident at Fukushima Nuclear Power Plant

    PubMed Central

    Orita, Makiko; Hayashida, Naomi; Nakayama, Yumi; Shinkawa, Tetsuko; Urata, Hideko; Fukushima, Yoshiko; Endo, Yuuko; Yamashita, Shunichi; Takamura, Noboru

    2015-01-01

    The late health effects of low-dose rate radiation exposure are still a serious public concern in the Fukushima area even four years after the accident at Fukushima Daiichi Nuclear Power Plant (FNPP). To clarify the factors associated with residents’ risk perception of radiation exposure and consequent health effects, we conducted a survey among residents of Kawauchi village in May and June 2014, which is located within 30 km of FNPP. 85 of 285 residents (29.8%) answered that acute radiation syndrome might develop in residents after the accident, 154 (54.0%) residents responded that they had anxieties about the health effects of radiation on children, and 140 (49.1%) residents indicated that they had anxieties about the health effects of radiation on offspring. Furthermore, 107 (37.5%) residents answered that they had concerns about health effects that would appear in the general population simply by living in an environment with a 0.23 μSv per hour ambient dose for one year, 149 (52.2%) residents reported that they were reluctant to eat locally produced foods, and 164 (57.5%) residents believed that adverse health effects would occur in the general population by eating 100 Bq per kg of mushrooms every day for one year. The present study shows that a marked bipolarization of the risk perception about the health effects of radiation among residents could have a major impact on social well-being after the accident at FNPP. PMID:26057539

  13. Bipolarization of Risk Perception about the Health Effects of Radiation in Residents after the Accident at Fukushima Nuclear Power Plant.

    PubMed

    Orita, Makiko; Hayashida, Naomi; Nakayama, Yumi; Shinkawa, Tetsuko; Urata, Hideko; Fukushima, Yoshiko; Endo, Yuuko; Yamashita, Shunichi; Takamura, Noboru

    2015-01-01

    The late health effects of low-dose rate radiation exposure are still a serious public concern in the Fukushima area even four years after the accident at Fukushima Daiichi Nuclear Power Plant (FNPP). To clarify the factors associated with residents' risk perception of radiation exposure and consequent health effects, we conducted a survey among residents of Kawauchi village in May and June 2014, which is located within 30 km of FNPP. 85 of 285 residents (29.8%) answered that acute radiation syndrome might develop in residents after the accident, 154 (54.0%) residents responded that they had anxieties about the health effects of radiation on children, and 140 (49.1%) residents indicated that they had anxieties about the health effects of radiation on offspring. Furthermore, 107 (37.5%) residents answered that they had concerns about health effects that would appear in the general population simply by living in an environment with a 0.23 μSv per hour ambient dose for one year, 149 (52.2%) residents reported that they were reluctant to eat locally produced foods, and 164 (57.5%) residents believed that adverse health effects would occur in the general population by eating 100 Bq per kg of mushrooms every day for one year. The present study shows that a marked bipolarization of the risk perception about the health effects of radiation among residents could have a major impact on social well-being after the accident at FNPP. PMID:26057539

  14. 4.2 Methods for Internal Dosimetry

    NASA Astrophysics Data System (ADS)

    Noßke, D.; Mattsson, S.; Johansson, L.

    This document is part of Subvolume A 'Fundamentals and Data in Radiobiology, Radiation Biophysics, Dosimetry and Medical Radiological Protection' of Volume 7 'Medical Radiological Physics' of Landolt-Börnstein - Group VIII 'Advanced Materials and Technologies'. It contains the Section '4.2 Methods for Internal Dosimetry' of the Chapter '4 Dosimetry in Nuclear Medicine Diagnosis and Therapy' with the contents:

  15. Correction-less dosimetry of nonstandard photon fields: a new criterion to determine the usability of radiation detectors.

    PubMed

    Kamio, Y; Bouchard, H

    2014-09-01

    In the IAEA-AAPM dosimetry formalism, detector measurements in general nonstandard conditions are corrected using the factor k(f(clin),f(msr))(Q(clin),Q(msr)). This factor needs to be evaluated on a case-by-case basis which is difficult to accomplish in practice. The present paper aims to provide a method that allows neglecting correction factors for small and composite IMRT fields by first determining a radiation detector's usability in these fields. Detailed models of nine radiation detectors are built: four ionization chambers (NE2571, A12, A1SL, A14), three small field detectors (PTW31018 microLion, PTW60003 natural diamond, PTW60012 unshielded diode) and two near water-equivalent detectors (alanine, W1 scintillating fiber). Using the egs_chamber Monte Carlo code, dose response functions at 6 MV and 25 MV are sampled for each detector and their corresponding volume of water. These functions are then used with a newly derived criterion to evaluate an upper bound ξ(f(ns),f(msr))(Q(ns),Q(msr)) on the variable ε(f(ns),f(msr))(Q(ns),Q(msr)) if no field collimation/modulation occurs over a given perturbation zone. The variable ε(f(ns),f(msr))(Q(ns),Q(msr)) is defined as the absolute value of the relative deviation from unity of a nonstandard field quality correction factor k(f(ns),f(msr))(Q(ns),Q(msr)). Using the same criterion, perturbation zones are evaluated by finding the smallest field size allowed for correction-less dosimetry with a given tolerance ξ(f(ns),f(msr))(Q(ns),Q(msr)). For composite fields, the sensitivity of detectors to the non-uniformity of virtual symmetric collapsed beams over regions of interest specified by the criterion is studied to estimate an upper bound ξ ̃(f(ns),f(ref))(Q(ns),Q) on ε(f(ns),f(ref))(Q(ns),Q) for a given beam flatness. Finally, a newly defined perturbation function is used to minimize the perturbations of the microLion chamber through density compensation. The theoretical criterion shows good agreement with full

  16. The International Reactor Dosimetry File.

    1994-01-19

    Version 01 The International Reactor Dosimetry File (IRDF-90) contains recommended neutron cross-section data to be used for reactor neutron dosimetry by foil activation. It also contains selected recommended values for radiation damage cross-sections and benchmark neutron spectra. This library supersedes all earlier versions of IRDF.

  17. Development of defects in the structure of PIN dosimetry diodes exposed to gamma radiation

    NASA Astrophysics Data System (ADS)

    Sopko, V.; Sopko, B.; Chren, D.; Dammer, J.

    2013-12-01

    Studies of radiation induced defects continue to be relevant as they find an ever greater application due to the increasing radiation doses to which semiconductor detectors are exposed. Efforts of figuring out the changes due to high radiation doses provide the fundamental motivation for this type of experiments. The PIN diode is described, and a developmental disorder caused thereto by 60Co source gamma quanta ranging from 100 kGy to 1 MGy. The calibration curve shows the effect of disturbances on the volt-ampere characteristics as a function of the dose of gamma radiation. The results are compared with earlier published data.

  18. Jaw Dysfunction Related to Pterygoid and Masseter Muscle Dosimetry After Radiation Therapy in Children and Young Adults With Head-and-Neck Sarcomas

    SciTech Connect

    Krasin, Matthew J.; Wiese, Kristin M.; Spunt, Sheri L.; Hua, Chia-ho; Daw, Najat; Navid, Fariba; Davidoff, Andrew M.; McGregor, Lisa; Merchant, Thomas E.; Kun, Larry E.; McCrarey, Lola; and others

    2012-01-01

    Purpose: To investigate the relationship between jaw function, patient and treatment variables, and radiation dosimetry of the mandibular muscles and joints in children and young adults receiving radiation for soft-tissue and bone sarcomas. Methods and Materials: Twenty-four pediatric and young adult patients with head-and-neck sarcomas were treated on an institutional review board-approved prospective study of focal radiation therapy for local tumor control. Serial jaw depression measurements were related to radiation dosimetry delivered to the medial and lateral pterygoid muscles, masseter muscles, and temporomandibular joints to generate mathematical models of jaw function. Results: Baseline jaw depression was only influenced by the degree of surgical resection. In the first 12 weeks from initiation of radiation, surgical procedures greater than a biopsy, administration of cyclophosphamide containing chemotherapy regimes, and large gross tumor volumes adversely affected jaw depression. Increasing dose to the pterygoid and masseter muscles above 40 Gy predicted loss of jaw function over the full course of follow-up. Conclusions: Clinical and treatment factors are related to initial and subsequent jaw dysfunction. Understanding these complex interactions and the affect of specific radiation doses may help reduce the risk for jaw dysfunction in future children and young adults undergoing radiation therapy for the management of soft-tissue and bone sarcomas.

  19. Quantitative imaging for clinical dosimetry

    NASA Astrophysics Data System (ADS)

    Bardiès, Manuel; Flux, Glenn; Lassmann, Michael; Monsieurs, Myriam; Savolainen, Sauli; Strand, Sven-Erik

    2006-12-01

    Patient-specific dosimetry in nuclear medicine is now a legal requirement in many countries throughout the EU for targeted radionuclide therapy (TRT) applications. In order to achieve that goal, an increased level of accuracy in dosimetry procedures is needed. Current research in nuclear medicine dosimetry should not only aim at developing new methods to assess the delivered radiation absorbed dose at the patient level, but also to ensure that the proposed methods can be put into practice in a sufficient number of institutions. A unified dosimetry methodology is required for making clinical outcome comparisons possible.

  20. Compounds of 6Li and natural Li for EPR dosimetry in photon/neutron mixed radiation fields.

    PubMed

    Lund, E; Gustafsson, H; Danilczuk, M; Sastry, M D; Lund, A

    2004-05-01

    Formates and dithionates of 6Li, enriched and 7Li in natural composition of Li offer a possibility to measure the absorbed dose from photons and thermal neutrons in a mixed radiation field for instance at a boron neutron capture therapy (BNCT) facility. Tests with formates and dithionates of enriched 6Li and lithium compounds with natural composition have been performed at the BNCT facility at Studsvik, Sweden. Irradiations have been performed at 3 cm depth in a Perspex phantom in a fluence rate of thermal neutrons 1.8 x 10(9) n cm(-2) s(-1). The compounds were also irradiated in a pure X-ray field from a 4MV linear accelerator at 5 cm depth in a phantom with accurately determined absorbed doses. The signal intensity and shape was investigated within 3 h after the irradiation. A single line spectrum attributed to the CO2- radical was observed after irradiation of lithium formate. An increase in line width occurring after neutron irradiation in comparison with photon irradiation of the 6Li sample was attributed to dipolar broadening between CO2- radicals trapped in the tracks of the alpha particles. A spectrum due to the SO3- radical anion was observed after irradiation of lithium dithionate. The signal amplitude increased using the 6Li in place of the Li with natural composition of isotopes, in studies with low energy X-ray irradiation. Due to the decreased line width, caused by the difference in g(N) and I between the isotopes, the sensitivity with 6Li dithionate may be enhanced by an order of magnitude compared to alanine dosimetry. After comprehensive examination of the different combinations of compounds with different amounts of 6Li and 7Li regarding dosimetry, radiation chemistry and EPR properties these dosimeter material might be used for dose determinations at BNCT treatments and for biomedical experiments. Interesting properties of the radical formation might be visible due to the large difference in ionization density of neutrons compared to photons.

  1. Normoxic polymer gel dosimetry using less toxic monomer of N-isopropyl acrylamide and X-ray computed tomography for radiation therapy applications

    PubMed Central

    Ghavami, Seyed-Mostafa; Mesbahi, Asghar; Pesianian, Ismaeel; Shafaee, Abbas; Aliparasti, Mohammad-Reza

    2010-01-01

    Background Polymer gel dosimetry has been used extensively in radiation therapy for its capability in depicting a three dimensional view of absorbed dose distribution. However, more studies are required to find less toxic and more efficient polymers for application in radiotherapy dosimetry. Aim The purpose of this work was to evaluate the N-isopropyl acrylamide (NIPAM) gel dosimetric characteristics and optimize the protocol for X-ray computed tomography (CT) imaging of gel dosimeters for radiation therapy application. Material and methods A polymer gel dosimeter based on NIPAM monomer was prepared and irradiated with 60Co photons. The CT number changes following irradiation were extracted from CT images obtained with different sets of imaging parameters. Results The results showed the dose sensitivity of ΔNCT (H) = 0.282 ± 0.018 (H Gy−1) for NIPAM gel dosimeter. The optimized set of imaging exposure parameters was 120 kVp and 200 mA with the 10 mm slice thickness. Results of the depth dose measurement with gel dosimeter showed a great discrepancy with the actual depth dose data. Conclusion According to the current study, NIPAM-based gel dosimetry with X-ray CT imaging needs more technical development and formulation refinement to be used for radiation therapy application. PMID:24376945

  2. AMS applied to Hiroshima and Chernobyl dosimetry

    SciTech Connect

    Straume, T.; Marchetti, A.A.; Anspaugh, L.R.

    1995-12-01

    Two projects employing AMS are summarized and updated. One project employs AMS to measure {sup 36}Cl in concrete and other mineral samples from Hiroshima and Nagasaki to help reconstruct neutron fluences received by the atom-bomb survivors. In this project, we have demonstrated a large discrepancy between the neutron activation measured in Hiroshima and predictions based on the current dosimetry system. This discrepancy has practical implications for radiation risk assessment and radiation protection standards. The other project employs AMS to measure {sup 129}I in soil and other environmental samples from Belarus, Ukraine, and Russia. This is a proof-of-principle study to determine if the long lived {sup 129}I isotope (half life, 16 x 10{sup 6} y) measured by AMS can be used to reconstruct deposition of the short lived {sup 131}I isotope from the 1986 Chernobyl reactor accident. This is required because {sup 131}I disappeared before adequate measurements could be made.

  3. Workshop Report on Atomic Bomb Dosimetry--Review of Dose Related Factors for the Evaluation of Exposures to Residual Radiation at Hiroshima and Nagasaki.

    PubMed

    Kerr, George D; Egbert, Stephen D; Al-Nabulsi, Isaf; Bailiff, Ian K; Beck, Harold L; Belukha, Irina G; Cockayne, John E; Cullings, Harry M; Eckerman, Keith F; Granovskaya, Evgeniya; Grant, Eric J; Hoshi, Masaharu; Kaul, Dean C; Kryuchkov, Victor; Mannis, Daniel; Ohtaki, Megu; Otani, Keiko; Shinkarev, Sergey; Simon, Steven L; Spriggs, Gregory D; Stepanenko, Valeriy F; Stricklin, Daniela; Weiss, Joseph F; Weitz, Ronald L; Woda, Clemens; Worthington, Patricia R; Yamamoto, Keiko; Young, Robert W

    2015-12-01

    Groups of Japanese and American scientists, supported by international collaborators, have worked for many years to ensure the accuracy of the radiation dosimetry used in studies of health effects in the Japanese atomic bomb survivors. Reliable dosimetric models and systems are especially critical to epidemiologic studies of this population because of their importance in the development of worldwide radiation protection standards. While dosimetry systems, such as Dosimetry System 1986 (DS86) and Dosimetry System 2002 (DS02), have improved, the research groups that developed them were unable to propose or confirm an additional contribution by residual radiation to the survivor's total body dose. In recognition of the need for an up-to-date review of residual radiation exposures in Hiroshima and Nagasaki, a half-day technical session was held for reports on newer studies at the 59 th Annual HPS Meeting in 2014 in Baltimore, MD. A day-and-a-half workshop was also held to provide time for detailed discussion of the newer studies and to evaluate their potential use in clarifying the residual radiation exposure to atomic bomb survivors at Hiroshima and Nagasaki. The process also involved a re-examination of very early surveys of radioisotope emissions from ground surfaces at Hiroshima and Nagasaki and early reports of health effects. New insights were reported on the potential contribution to residual radiation from neutron-activated radionuclides in the airburst's dust stem and pedestal and in unlofted soil, as well as from fission products and weapon debris from the nuclear cloud. However, disparate views remain concerning the actual residual radiation doses received by the atomic bomb survivors at different distances from the hypocenter. The workshop discussion indicated that measurements made using thermal luminescence and optically stimulated luminescence, like earlier measurements, especially in very thin layers of the samples, could be expanded to detect possible

  4. Workshop Report on Atomic Bomb Dosimetry--Review of Dose Related Factors for the Evaluation of Exposures to Residual Radiation at Hiroshima and Nagasaki.

    PubMed

    Kerr, George D; Egbert, Stephen D; Al-Nabulsi, Isaf; Bailiff, Ian K; Beck, Harold L; Belukha, Irina G; Cockayne, John E; Cullings, Harry M; Eckerman, Keith F; Granovskaya, Evgeniya; Grant, Eric J; Hoshi, Masaharu; Kaul, Dean C; Kryuchkov, Victor; Mannis, Daniel; Ohtaki, Megu; Otani, Keiko; Shinkarev, Sergey; Simon, Steven L; Spriggs, Gregory D; Stepanenko, Valeriy F; Stricklin, Daniela; Weiss, Joseph F; Weitz, Ronald L; Woda, Clemens; Worthington, Patricia R; Yamamoto, Keiko; Young, Robert W

    2015-12-01

    Groups of Japanese and American scientists, supported by international collaborators, have worked for many years to ensure the accuracy of the radiation dosimetry used in studies of health effects in the Japanese atomic bomb survivors. Reliable dosimetric models and systems are especially critical to epidemiologic studies of this population because of their importance in the development of worldwide radiation protection standards. While dosimetry systems, such as Dosimetry System 1986 (DS86) and Dosimetry System 2002 (DS02), have improved, the research groups that developed them were unable to propose or confirm an additional contribution by residual radiation to the survivor's total body dose. In recognition of the need for an up-to-date review of residual radiation exposures in Hiroshima and Nagasaki, a half-day technical session was held for reports on newer studies at the 59 th Annual HPS Meeting in 2014 in Baltimore, MD. A day-and-a-half workshop was also held to provide time for detailed discussion of the newer studies and to evaluate their potential use in clarifying the residual radiation exposure to atomic bomb survivors at Hiroshima and Nagasaki. The process also involved a re-examination of very early surveys of radioisotope emissions from ground surfaces at Hiroshima and Nagasaki and early reports of health effects. New insights were reported on the potential contribution to residual radiation from neutron-activated radionuclides in the airburst's dust stem and pedestal and in unlofted soil, as well as from fission products and weapon debris from the nuclear cloud. However, disparate views remain concerning the actual residual radiation doses received by the atomic bomb survivors at different distances from the hypocenter. The workshop discussion indicated that measurements made using thermal luminescence and optically stimulated luminescence, like earlier measurements, especially in very thin layers of the samples, could be expanded to detect possible

  5. Exobiology at Southern Brazil: Spore Dosimetry and the UV Solar Radiation

    NASA Astrophysics Data System (ADS)

    Rampelotto, P. H.; Rosa, M. B.; Schuch, N. J.; Pinheiro, D. K.; Schuch, A. P.; Munakata, N.

    2009-12-01

    The ultraviolet - UV is considered the range of solar radiation most immediately lethal to the life organisms on the Earth’s surface. In this context, since 2000, the monitoring of the biologically-effective solar radiation using spore dosimeter at the Southern Space Observatory (29.4° S, 53.8° W), South of Brazil, has been performed. The biological dosimeter is based in the spore inactivation doses of Bacillus subtilis strain TKJ6312, who is sensitive to the UV solar radiation. Monthly expositions of biological dosimeter have been compared with solar irradiance obtained by Brewer spectrophotometer. Correlations indices about r > 0.86 shows the potential applicability of the biosensor in the monitoring of biologically-effective solar radiation. Since spores are stabile microorganisms, considering extreme environment variations, the biosensor may be used for studies of the effects of the solar radiation in others planetary environments for future work.

  6. Ramifications of target motion in localization and dosimetry for stereotactic body radiation therapy

    NASA Astrophysics Data System (ADS)

    Tanyi, James Ayuk

    2005-11-01

    Several key analytical/experimental studies have been conducted to quantify the magnitude of the consequential effect of motion both at the level of target localization and characterization and dose delivery. In the imaging front, Chen et al., 2004 showed that distortions along the axis of motion could result in (1) target lengthening or shortening, (2) target over- or under- estimation, and (3) displacement of reference target centroid by as much as the amplitude of the motion of a target. The authors concluded that the geometric distortion depended on motion phase, motion amplitude, and scan speed, phase being the primary determinant of the resulting type of distortion. In the dosimetry front, Yang et al., 1997 investigated the interplay effect in tomotherapy delivery. Yu et al ., 1998 and Jiang et al., 2003 investigated the interplay effect for MLC-based IMRT. To supplement current understanding of the effects of motion, this study will be divided into two steps. (1) Characterization of potential systematic errors introduced into a patient plan if appropriate steps are not taken to eliminate, or at least, minimize, tumor motion. (2) Quantification of the accuracy of delivering large dose fractions compared to small dose fractions with constant motion period. Actual measurements are performed on a dynamic anthropomorphic phantom. To not base claims regarding accuracy of equipment, quality of dose distributions, and dose tolerance on the virtual computer simulation of the treatment plan, a suitable dosimeter is identified and its response characterized for use in dose measurements.

  7. Improved Radiation Dosimetry/Risk Estimates to Facilitate Environmental Management of Plutonium Contaminated Sites

    SciTech Connect

    Scott, Bobby R.; Cheng, Yung-Sung; Zhou, Yue; Tokarskaya, Zoya B.; Zhuntova, Galina V.

    2003-06-11

    Our Phase II research evaluated health risks associated with inhaled plutonium. Our research objectives were to: (1) extend our stochastic model for deposition of plutonium in the respiratory tract to include additional key variability and uncertainty; (2) generate and analyze risk distributions for deterministic effects in the lung from inhaled plutonium that reflect risk model uncertainty; (3) acquire an improved understanding of key physiological effects of inhaled plutonium, based on evaluations of clinical data (e.g., hematological, respiratory function, chromosomal aberrations in lymphocytes) for Mayak workers in Russia who inhaled plutonium-239; (4) develop biological dosimetry for plutonium-239 that was inhaled by some Mayak workers (with unknown intake) based on clinical data for other workers with known plutonium-239 intake; (5) critically evaluate the validity of the linear no-threshold (LNT) risk model as it relates to cancer risks from inhaled plutonium-239 (base d on Mayak worker data); and (6) evaluate respirator filter penetration frequencies for airborne plutonium aerosols using surrogate high-density metals.

  8. Improved Radiation Dosimetry/Risk Estimates to Facilitate Environmental Management of Plutonium Contaminated Sites

    SciTech Connect

    Scott, Bobby R.; Cheng, Yung-Sung; Zhou, Yue; Tokarskaya, Zoya B.; Zhuntova, Galina V.

    2002-07-10

    Our phase-II research relates to evaluating health risks associated with inhaled plutonium (Pu). Our current research objectives are as follows: (1) to extend our stochastic model for deposition of plutonium (Pu) in the respiratory tract to include additional key variability and uncertainty; (2) to generate and analyze risk distributions for deterministic effects in the lung from inhaled Pu that reflect risk model uncertainty; (3) to acquire an improved understanding of key physiological effects of inhaled Pu, based on evaluations of clinical data (e.g., hematological, respiratory function, chromosomal aberrations in lymphocytes) for Mayak workers in Russia that inhaled Pu- 239; (4) to develop biological dosimetry for Pu-239 that was inhaled by some Mayak workers (with unknown intake) based on clinical data for other workers with known Pu-239 intake; (5) to critically evaluate the validity of the linear no-threshold (LNT) risk model as it relates to cancer risks from inhaled Pu-239 (based on Mayak worker data); (6) to evaluate respirator filter penetration frequencies for airborne Pu aerosols using surrogate high density metals.

  9. Fundamentals of materials, techniques and instrumentation for OSL and FNTD dosimetry

    NASA Astrophysics Data System (ADS)

    Akselrod, M. S.

    2013-02-01

    The optically stimulated luminescence (OSL) technique has already become a successful commercial tool in personal radiation dosimetry, medical dosimetry, diagnostic imaging, geological and archeological dating. This review briefly describes the history and fundamental principles of OSL materials, methods and instrumentation. The advantages of OSL technology and instrumentation in comparison with thermoluminescent technique are analyzed. Progress in material and detector engineering has allowed new and promising developments regarding OSL applications in the medical field. Special attention is dedicated to Al2O3:C as a material of choice for many dosimetric applications including fiberoptic OSL/RL sensors with diameters as small as 300 μm. A new RL/OSL fiberoptic system has a high potential for in vivo and in vitro dosimetry in both radiation therapy and diagnostic mammography. Different aspects of instrumentation, data processing algorithms, post-irradiation and real-time measurements are described. The next technological breakthrough was done with Fluorescent Nuclear Track detectors (FNTD) that has some important advantages in measuring fast neutron and high energy heavy charge particles that became the latest tool in radiation therapy. New Mg-doped aluminum oxide crystals and novel type of imaging instrumentation for FNTD technology were engineered and successfully demonstrated for occupational and accident dosimetry, for medical dosimetry and radiobiological research.

  10. Topical Review: Polymer gel dosimetry

    PubMed Central

    Baldock, C; De Deene, Y; Doran, S; Ibbott, G; Jirasek, A; Lepage, M; McAuley, K B; Oldham, M; Schreiner, L J

    2010-01-01

    Polymer gel dosimeters are fabricated from radiation sensitive chemicals which, upon irradiation, polymerize as a function of the absorbed radiation dose. These gel dosimeters, with the capacity to uniquely record the radiation dose distribution in three-dimensions (3D), have specific advantages when compared to one-dimensional dosimeters, such as ion chambers, and two-dimensional dosimeters, such as film. These advantages are particularly significant in dosimetry situations where steep dose gradients exist such as in intensity-modulated radiation therapy (IMRT) and stereotactic radiosurgery. Polymer gel dosimeters also have specific advantages for brachytherapy dosimetry. Potential dosimetry applications include those for low-energy x-rays, high-linear energy transfer (LET) and proton therapy, radionuclide and boron capture neutron therapy dosimetries. These 3D dosimeters are radiologically soft-tissue equivalent with properties that may be modified depending on the application. The 3D radiation dose distribution in polymer gel dosimeters may be imaged using magnetic resonance imaging (MRI), optical-computerized tomography (optical-CT), x-ray CT or ultrasound. The fundamental science underpinning polymer gel dosimetry is reviewed along with the various evaluation techniques. Clinical dosimetry applications of polymer gel dosimetry are also presented. PMID:20150687

  11. Lyoluminescence, thermoluminescence and mechanoluminescence studies in γ-ray irradiated Dy3+ activated potassium chloride phosphor for accidental radiation dosimetry.

    PubMed

    Bhujbal, P M; Dhoble, S J

    2012-01-01

    The lyoluminescence (LL), thermoluminescence (TL) and mechanoluminescence (ML) of γ-ray-irradiated coloured powder of KCl:Dy (0.05-0.5 mol%) phosphors are reported in this paper. To understand the mechanism of LL and ML, the LL and ML spectra are compared with TL studies. The variation of intensity of respective luminescence with different γ-ray doses and with different concentrations of Dy3+ ion doped in KCl is found to be similar in nature. The intensities differ from each other, but their nature is found to be similar with γ-ray exposures. The ML glow peak intensity is linear up to high 1 kGy exposure as compared to LL (up to 0.5 kGy) and TL (up to 0.75 kGy) techniques. Therefore, according to our results, the recommendation is that KCl:Dy (0.1 mol%) phosphor prepared by wet chemical technique is useful for high-dose measurements using the ML technique for accidental radiation dosimetry.

  12. 3D printer generated thorax phantom with mobile tumor for radiation dosimetry.

    PubMed

    Mayer, Rulon; Liacouras, Peter; Thomas, Andrew; Kang, Minglei; Lin, Liyong; Simone, Charles B

    2015-07-01

    This article describes the design, construction, and properties of an anthropomorphic thorax phantom with a moving surrogate tumor. This novel phantom permits detection of dose both inside and outside a moving tumor and within the substitute lung tissue material. A 3D printer generated the thorax shell composed of a chest wall, spinal column, and posterior regions of the phantom. Images of a computed tomography scan of the thorax from a patient with lung cancer provided the template for the 3D printing. The plastic phantom is segmented into two materials representing the muscle and bones, and its geometry closely matches a patient. A surrogate spherical plastic tumor controlled by a 3D linear stage simulates a lung tumor's trajectory during normal breathing. Sawdust emulates the lung tissue in terms of average and distribution in Hounsfield numbers. The sawdust also provides a forgiving medium that permits tumor motion and sandwiching of radiochromic film inside the mobile surrogate plastic tumor for dosimetry. A custom cork casing shields the film and tumor and eliminates film bending during extended scans. The phantom, lung tissue surrogate, and radiochromic film are exposed to a seven field plan based on an ECLIPSE plan for 6 MV photons from a Trilogy machine delivering 230 cGy to the isocenter. The dose collected in a sagittal plane is compared to the calculated plan. Gamma analysis finds 8.8% and 5.5% gamma failure rates for measurements of large amplitude trajectory and static measurements relative to the large amplitude plan, respectively. These particular gamma analysis results were achieved using parameters of 3% dose and 3 mm, for regions receiving doses >150 cGy. The plan assumes a stationary detection grid unlike the moving radiochromic film and tissues. This difference was experimentally observed and motivated calculated dose distributions that incorporated the phase of the tumor periodic motion. These calculations modestly improve agreement between

  13. Focusing optics of a parallel beam CCD optical tomography apparatus for 3D radiation gel dosimetry.

    PubMed

    Krstajić, Nikola; Doran, Simon J

    2006-04-21

    Optical tomography of gel dosimeters is a promising and cost-effective avenue for quality control of radiotherapy treatments such as intensity-modulated radiotherapy (IMRT). Systems based on a laser coupled to a photodiode have so far shown the best results within the context of optical scanning of radiosensitive gels, but are very slow ( approximately 9 min per slice) and poorly suited to measurements that require many slices. Here, we describe a fast, three-dimensional (3D) optical computed tomography (optical-CT) apparatus, based on a broad, collimated beam, obtained from a high power LED and detected by a charged coupled detector (CCD). The main advantages of such a system are (i) an acquisition speed approximately two orders of magnitude higher than a laser-based system when 3D data are required, and (ii) a greater simplicity of design. This paper advances our previous work by introducing a new design of focusing optics, which take information from a suitably positioned focal plane and project an image onto the CCD. An analysis of the ray optics is presented, which explains the roles of telecentricity, focusing, acceptance angle and depth-of-field (DOF) in the formation of projections. A discussion of the approximation involved in measuring the line integrals required for filtered backprojection reconstruction is given. Experimental results demonstrate (i) the effect on projections of changing the position of the focal plane of the apparatus, (ii) how to measure the acceptance angle of the optics, and (iii) the ability of the new scanner to image both absorbing and scattering gel phantoms. The quality of reconstructed images is very promising and suggests that the new apparatus may be useful in a clinical setting for fast and accurate 3D dosimetry. PMID:16585845

  14. 3D printer generated thorax phantom with mobile tumor for radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Mayer, Rulon; Liacouras, Peter; Thomas, Andrew; Kang, Minglei; Lin, Liyong; Simone, Charles B.

    2015-07-01

    This article describes the design, construction, and properties of an anthropomorphic thorax phantom with a moving surrogate tumor. This novel phantom permits detection of dose both inside and outside a moving tumor and within the substitute lung tissue material. A 3D printer generated the thorax shell composed of a chest wall, spinal column, and posterior regions of the phantom. Images of a computed tomography scan of the thorax from a patient with lung cancer provided the template for the 3D printing. The plastic phantom is segmented into two materials representing the muscle and bones, and its geometry closely matches a patient. A surrogate spherical plastic tumor controlled by a 3D linear stage simulates a lung tumor's trajectory during normal breathing. Sawdust emulates the lung tissue in terms of average and distribution in Hounsfield numbers. The sawdust also provides a forgiving medium that permits tumor motion and sandwiching of radiochromic film inside the mobile surrogate plastic tumor for dosimetry. A custom cork casing shields the film and tumor and eliminates film bending during extended scans. The phantom, lung tissue surrogate, and radiochromic film are exposed to a seven field plan based on an ECLIPSE plan for 6 MV photons from a Trilogy machine delivering 230 cGy to the isocenter. The dose collected in a sagittal plane is compared to the calculated plan. Gamma analysis finds 8.8% and 5.5% gamma failure rates for measurements of large amplitude trajectory and static measurements relative to the large amplitude plan, respectively. These particular gamma analysis results were achieved using parameters of 3% dose and 3 mm, for regions receiving doses >150 cGy. The plan assumes a stationary detection grid unlike the moving radiochromic film and tissues. This difference was experimentally observed and motivated calculated dose distributions that incorporated the phase of the tumor periodic motion. These calculations modestly improve agreement between

  15. 3D printer generated thorax phantom with mobile tumor for radiation dosimetry

    SciTech Connect

    Mayer, Rulon; Liacouras, Peter; Thomas, Andrew; Kang, Minglei; Lin, Liyong; Simone, Charles B.

    2015-07-15

    This article describes the design, construction, and properties of an anthropomorphic thorax phantom with a moving surrogate tumor. This novel phantom permits detection of dose both inside and outside a moving tumor and within the substitute lung tissue material. A 3D printer generated the thorax shell composed of a chest wall, spinal column, and posterior regions of the phantom. Images of a computed tomography scan of the thorax from a patient with lung cancer provided the template for the 3D printing. The plastic phantom is segmented into two materials representing the muscle and bones, and its geometry closely matches a patient. A surrogate spherical plastic tumor controlled by a 3D linear stage simulates a lung tumor’s trajectory during normal breathing. Sawdust emulates the lung tissue in terms of average and distribution in Hounsfield numbers. The sawdust also provides a forgiving medium that permits tumor motion and sandwiching of radiochromic film inside the mobile surrogate plastic tumor for dosimetry. A custom cork casing shields the film and tumor and eliminates film bending during extended scans. The phantom, lung tissue surrogate, and radiochromic film are exposed to a seven field plan based on an ECLIPSE plan for 6 MV photons from a Trilogy machine delivering 230 cGy to the isocenter. The dose collected in a sagittal plane is compared to the calculated plan. Gamma analysis finds 8.8% and 5.5% gamma failure rates for measurements of large amplitude trajectory and static measurements relative to the large amplitude plan, respectively. These particular gamma analysis results were achieved using parameters of 3% dose and 3 mm, for regions receiving doses >150 cGy. The plan assumes a stationary detection grid unlike the moving radiochromic film and tissues. This difference was experimentally observed and motivated calculated dose distributions that incorporated the phase of the tumor periodic motion. These calculations modestly improve agreement between

  16. Focusing optics of a parallel beam CCD optical tomography apparatus for 3D radiation gel dosimetry

    NASA Astrophysics Data System (ADS)

    Krstajic, Nikola; Doran, Simon J.

    2006-04-01

    Optical tomography of gel dosimeters is a promising and cost-effective avenue for quality control of radiotherapy treatments such as intensity-modulated radiotherapy (IMRT). Systems based on a laser coupled to a photodiode have so far shown the best results within the context of optical scanning of radiosensitive gels, but are very slow (~9 min per slice) and poorly suited to measurements that require many slices. Here, we describe a fast, three-dimensional (3D) optical computed tomography (optical-CT) apparatus, based on a broad, collimated beam, obtained from a high power LED and detected by a charged coupled detector (CCD). The main advantages of such a system are (i) an acquisition speed approximately two orders of magnitude higher than a laser-based system when 3D data are required, and (ii) a greater simplicity of design. This paper advances our previous work by introducing a new design of focusing optics, which take information from a suitably positioned focal plane and project an image onto the CCD. An analysis of the ray optics is presented, which explains the roles of telecentricity, focusing, acceptance angle and depth-of-field (DOF) in the formation of projections. A discussion of the approximation involved in measuring the line integrals required for filtered backprojection reconstruction is given. Experimental results demonstrate (i) the effect on projections of changing the position of the focal plane of the apparatus, (ii) how to measure the acceptance angle of the optics, and (iii) the ability of the new scanner to image both absorbing and scattering gel phantoms. The quality of reconstructed images is very promising and suggests that the new apparatus may be useful in a clinical setting for fast and accurate 3D dosimetry.

  17. Measurement of stray radiation within a scanning proton therapy facility: EURADOS WG9 intercomparison exercise of active dosimetry systems

    SciTech Connect

    Farah, J. Trompier, F.; Mares, V.; Schinner, K.; Wielunski, M.; Romero-Expósito, M.; Domingo, C.; Trinkl, S.; Dufek, V.; Klodowska, M.; Liszka, M.; Stolarczyk, L.; Olko, P.; Kubancak, J.; and others

    2015-05-15

    Purpose: To characterize stray radiation around the target volume in scanning proton therapy and study the performance of active neutron monitors. Methods: Working Group 9 of the European Radiation Dosimetry Group (EURADOS WG9—Radiation protection in medicine) carried out a large measurement campaign at the Trento Centro di Protonterapia (Trento, Italy) in order to determine the neutron spectra near the patient using two extended-range Bonner sphere spectrometry (BSS) systems. In addition, the work focused on acknowledging the performance of different commercial active dosimetry systems when measuring neutron ambient dose equivalents, H{sup ∗}(10), at several positions inside (8 positions) and outside (3 positions) the treatment room. Detectors included three TEPCs—tissue equivalent proportional counters (Hawk type from Far West Technology, Inc.) and six rem-counters (WENDI-II, LB 6411, RadEye™ NL, a regular and an extended-range NM2B). Meanwhile, the photon component of stray radiation was deduced from the low-lineal energy transfer part of TEPC spectra or measured using a Thermo Scientific™ FH-40G survey meter. Experiments involved a water tank phantom (60 × 30 × 30 cm{sup 3}) representing the patient that was uniformly irradiated using a 3 mm spot diameter proton pencil beam with 10 cm modulation width, 19.95 cm distal beam range, and 10 × 10 cm{sup 2} field size. Results: Neutron spectrometry around the target volume showed two main components at the thermal and fast energy ranges. The study also revealed the large dependence of the energy distribution of neutrons, and consequently of out-of-field doses, on the primary beam direction (directional emission of intranuclear cascade neutrons) and energy (spectral composition of secondary neutrons). In addition, neutron mapping within the facility was conducted and showed the highest H{sup ∗}(10) value of ∼51 μSv Gy{sup −1}; this was measured at 1.15 m along the beam axis. H{sup ∗}(10) values

  18. Optically stimulated luminescence dosimetry

    NASA Astrophysics Data System (ADS)

    McKeever, Stephen W.

    1999-02-01

    Optically Stimulated Luminescence (OSL) dosimetry is attractive to the health physics and dosimetry community due to its all-optical character, fast data acquisition and the avoidance of heating the detector. Until recently there was no luminescent material sensitive enough to radiation, and at the same time suitable for stimulation with visible light, for use in this application. However, anion-deficient aluminum oxide doped with carbon (Al2O3:C) appears to be not only an extremely sensitive thermoluminescence (TL) material, but is also well-suited to OSL applications. Several OSL readout protocols have been suggested, including cw-OSL, pulsed OSL (POSL), and 'delayed' OSL (DOSL). The paper discusses the physical mechanisms that give rise to the OSL signals and the dependence of these signals upon absorbed dose. Example applications of the use of OSL from Al2O3:C in environmental radiation and ultraviolet-B dosimetry are discussed.

  19. Identification and evaluation of competencies of health professionals in the hospital emergency management of the radiation accident victim

    SciTech Connect

    Berger, M.E.

    1982-01-01

    A preliminary list of ten competency and forty-six sub-competency statements derived from literature and consultation with experts and based on the general areas of clinical performance defined by the National Board of Medical Examiners were the concern of Phase I of this study. Forty-eight experts in nuclear medicine, radiology, radiotherapy, health physics, medical physics, radiation biology, public and occupational health, surgery, and emergency medicine and nursing considered this preliminary list of competencies and sub-competencies to determine which were essential for health professionals who may be caring for radiation accident victims in hospital emergency departments. Eight competencies and thirty-three sub-competencies were rated as Essential competencies. Competencies dealing with establishing priorities in patient care and initiating treatment, assessment, contamination control, and decontamination were highly rated. In the second part of this study, the Essential competencies were utilized in the development of an original evaluation instrument designed to identify deficiencies and continuing education needs during radiation accident drills or exercises. The instrument was designed for use in sixteen possible patient care situations in which the radiation accident victims have varying medical and radiological conditions. Development of the evaluation instrument was described.

  20. Semen Quality of Workers Exposed to Ionizing Radiation in Decontamination Work after the Chernobyl Nuclear Reactor Accident.

    PubMed

    Bartoov; Zabludovsky; Eltes; Smirnov; Grischenko; Fischbein

    1997-07-01

    The objective of the study was to assess effects of radiation on sperm quality, including ultramorphology of spermatozoa of men who worked as salvage workers at the Chernobyl nuclear reactor accident site or in the adjacent region. Semen characteristics were assessed by light microscopy, biochemical analysis, and quantitative ultramorphologic analysis seven years after the accident. Samples were collected in the Ukraine, examined there by routine semen analysis, fixed, and transferred to Israel for further examinations. The study population consisted of 18 radiation-exposed individuals. Eighteen unexposed Ukrainian men were examined as controls. Sperm motility was found to be reduced in the radiation-exposed workers. Ultramorphologic defects were evident in the sperm nucleus. Fertility potential was adversely affected among the exposed workers. Thus, salvage workers who had worked at the Chernobyl nuclear reactor accident site or in the vicinity thereof were found to manifest ultramorphologic abnormalities in the sperm nucleus and to have impaired fertility potential seven years after the radiation exposure. The injury was independent of whether the work site had been located at the reactor site or in the vicinity thereof.

  1. Silicon-based three-dimensional microstructures for radiation dosimetry in hadrontherapy

    SciTech Connect

    Guardiola, C. Solberg, T.; Carabe, A.; Quirion, D.; Pellegrini, G.; Fleta, C.; Esteban, S.; Lozano, M.; Cortés-Giraldo, M. A.; Gómez, F.

    2015-07-13

    In this work, we propose a solid-state-detector for use in radiation microdosimetry. This device improves the performance of existing dosimeters using customized 3D-cylindrical microstructures etched inside silicon. The microdosimeter consists of an array of micro-sensors that have 3D-cylindrical electrodes of 15 μm diameter and a depth of 5 μm within a silicon membrane, resulting in a well-defined micrometric radiation sensitive volume. These microdetectors have been characterized using an {sup 241}Am source to assess their performance as radiation detectors in a high-LET environment. This letter demonstrates the capability of this microdetector to be used to measure dose and LET in hadrontherapy centers for treatment plan verification as part of their patient-specific quality control program.

  2. Dyed acrylic-acid grafted polypropylene films for high-dose radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Abdel-Fattah, A. A.; Said, F. I. A.; Ebraheem, S.; El-Kelany, M.; El Miligy, A. A.

    1999-03-01

    Gamma radiation-induced polymerization of acrylic acid (AAc) onto polypropylene (PP) film has been carried out under nitrogen atmosphere. The grafted film of PP-g-PAAc was allowed to react with solutions of two ionic dyes, namely malachite green (MALG) or methylene green (METG). The investigations show that these new dosimeter films of PPMALG and PPMETG may be useful for high-dose gamma radiation applications. The useful absorbed dose range of the dyed films extends up to about 400 kGy, with a minimum useful dose of about 5 kGy. The radiation-induced colour bleaching has been analyzed with visible spectrophotometry, either at the maximum of the absorption band peaking at 601 nm (for PPMETG) or that peaking at 623 nm for (PPMALG). The effects of relative humidity during irradiation, shelf-life and post-irradiation storage in dark and indirect daylight conditions on dosimeters performance are discussed.

  3. Design of organic scintillators for non-standard radiation field dosimetry: experimental setup.

    PubMed

    Norman H, Machado R; Maximiliano, Trujillo T; Javier E, García G; Diana C, Narvaez G; Paula A, Marín M; Róbinson A, Torres V

    2013-01-01

    This paper describes an experimental setup designed for sensing the luminescent light coming from an organic plastic scintillator stimulated with ionizing radiation. This device is intended to be a part of a complete dosimeter system for characterization of small radiation fields which is the project of the doctoral thesis of the medical physicist at the Radiation Oncology facility of Hospital San Vicente Fundación in conjunction with the Universidad de Antioquia of Medellín Colombia. Some preliminary results predict a good performance of the unit, but further studies must be conducted in order to have a completed evaluation of the system. This is the first step in the development of an accuracy tool for measurement of non-standard fields in the Radiotherapy or Radiosurgery processes. PMID:24110369

  4. Cell specific radiation dosimetry in skeleton from life-span carcinogenesis studies. Final report

    SciTech Connect

    Webster, S.S.J.

    1993-04-05

    The osteogenic sarcoma is the dominant life-threatening pathology in lifespan studies of beagles exposed to alpha-emitting bone-seeking radionuclides. It was deduced from these studies that certain skeletal sites are more prone to develop tumors. This project sought to determine the bone cells at risk and their cell-specific radiation dose. The cell-specific radiation dose values are related to loss and high Ra-226 and Pu-239 induced osteogenic sarcoma sites, to test different dose response hypothesis and predict the extent of effects in humans.

  5. Cell specific radiation dosimetry in skeleton from life-span carcinogenesis studies

    SciTech Connect

    Webster, S.S.J.

    1993-04-05

    The osteogenic sarcoma is the dominant life-threatening pathology in lifespan studies of beagles exposed to alpha-emitting bone-seeking radionuclides. It was deduced from these studies that certain skeletal sites are more prone to develop tumors. This project sought to determine the bone cells at risk and their cell-specific radiation dose. The cell-specific radiation dose values are related to loss and high Ra-226 and Pu-239 induced osteogenic sarcoma sites, to test different dose response hypothesis and predict the extent of effects in humans.

  6. Summary of radiation dosimetry results on U.S. and Soviet manned spacecraft

    NASA Technical Reports Server (NTRS)

    Benton, E. V.

    1986-01-01

    Measurements of the radiation environment aboard U.S. and Soviet manned spacecraft are reviewed and summarized. Data obtained mostly from passive and some active radiation detectors now exist for the case of low-earth-orbit missions. Major uncertainties still exist for space exposure in high-altitude, high-inclination geostationary orbits, in connection with solar effects and that of shielding. Data from active detectors flown in Spacelabs 1 and 2 suggest that a variety of phenomena must be understood before the effects of long-term exposure at the Space Station type of orbit and shielding can be properly assessed.

  7. Summary of radiation dosimetry results on U.S. and Soviet manned spacecraft.

    PubMed

    Benton, E V

    1986-01-01

    Measurements of the radiation environment aboard U.S. and Soviet manned spacecraft are reviewed and summarized. Data obtained mostly from passive and some active radiation detectors now exist for the case of low Earth-orbit missions. Major uncertainties still exist for space exposure in high altitude, high inclination, geostationary orbits, in connection with solar effects and that of shielding. Data from active detectors flown in Spacelabs 1 and 2 suggest that a variety of phenomena must be understood before the effects of long-term exposure at the space-station type of orbit and shielding can be properly assessed. PMID:11537239

  8. Proton Radiotherapy for Pediatric Bladder/Prostate Rhabdomyosarcoma: Clinical Outcomes and Dosimetry Compared to Intensity-Modulated Radiation Therapy

    SciTech Connect

    Cotter, Shane E.; Herrup, David A.; Friedmann, Alison; Macdonald, Shannon M.; Pieretti, Raphael V.; Robinson, Gregoire; Adams, Judith; Tarbell, Nancy J.; Yock, Torunn I.

    2011-12-01

    Purpose: In this study, we report the clinical outcomes of 7 children with bladder/prostate rhabdomyosarcoma (RMS) treated with proton radiation and compare proton treatment plans with matched intensity-modulated radiation therapy (IMRT) plans, with an emphasis on dose savings to reproductive and skeletal structures. Methods and Materials: Follow-up consisted of scheduled clinic appointments at our institution or direct communication with the treating physicians for referred patients. Each proton radiotherapy plan used for treatment was directly compared to an IMRT plan generated for the study. Clinical target volumes and normal tissue volumes were held constant to facilitate dosimetric comparisons. Each plan was optimized for target coverage and normal tissue sparing. Results: Seven male patients were treated with proton radiotherapy for bladder/prostate RMS at the Massachusetts General Hospital between 2002 and 2008. Median age at treatment was 30 months (11-70 months). Median follow-up was 27 months (10-90 months). Four patients underwent a gross total resection prior to radiation, and all patients received concurrent chemotherapy. Radiation doses ranged from 36 cobalt Gray equivalent (CGE) to 50.4 CGE. Five of 7 patients were without evidence of disease and with intact bladders at study completion. Target volume dosimetry was equivalent between the two modalities for all 7 patients. Proton radiotherapy led to a significant decrease in mean organ dose to the bladder (25.1 CGE vs. 33.2 Gy; p = 0.03), testes (0.0 CGE vs. 0.6 Gy; p = 0.016), femoral heads (1.6 CGE vs. 10.6 Gy; p = 0.016), growth plates (21.7 CGE vs. 32.4 Gy; p = 0.016), and pelvic bones (8.8 CGE vs. 13.5 Gy; p = 0.016) compared to IMRT. Conclusions: This study provides evidence of significant dose savings to normal structures with proton radiotherapy compared to IMRT and is well tolerated in this patient population. The long-term impact of these reduced doses can be tested in future studies

  9. On the uncertainties of photon mass energy-absorption coefficients and their ratios for radiation dosimetry.

    PubMed

    Andreo, Pedro; Burns, David T; Salvat, Francesc

    2012-04-21

    with those of Hubbell (1977 Rad. Res. 70 58-81), except for the lowest energy range (radiodiagnostic) where it is concluded that current databases and their systematic analysis represent an improvement over the older Hubbell estimations. The results for (µ(en)/ρ)(graphite,air) for the gamma-ray dosimetry range are moderately higher than those of Seltzer and Bergstrom (2005 private communication).

  10. Fifth international radiopharmaceutical dosimetry symposium

    SciTech Connect

    Watson, E.E.; Schlafke-Stelson, A.T.

    1992-05-01

    This meeting was held to exchange information on how to get better estimates of the radiation absorbed dose. There seems to be a high interest of late in patient dosimetry; discussions were held in the light of revised risk estimates for radiation. Topics included: Strategies of Dose Assessment; Dose Estimation for Radioimmunotherapy; Dose Calculation Techniques and Models; Dose Estimation for Positron Emission Tomography (PET); Kinetics for Dose Estimation; and Small Scale Dosimetry and Microdosimetry. (VC)

  11. [Retrospective Cytogenetic Dose Evaluation. II. Computer Data Processing in Persons Irradiated in Different Radiation Accidents].

    PubMed

    Nugis, V Yu; Khvostunov, I K; Goloub, E V; Kozlova, M G; Nadejinal, N M; Galstian, I A

    2015-01-01

    The method for retrospective dose assessment based on the analysis of cell distribution by the number of dicentrics and unstable aberrations using a special computer program was earlier developed based on the data about the persons irradiated as a result of the accident at the Chernobyl nuclear power plant. This method was applied for the same purpose for data processing of repeated cytogenetic studies of the patients exposed to γ-, γ-β- or γ-neutron radiation in various situations. As a whole, this group was followed up in more distant periods (17-50 years) after exposure than Chernobyl patients (up to 25 years). The use for retrospective dose assessment of the multiple regression equations obtained for the Chernobyl cohort showed that the equation, which includes computer recovered estimate of the dose and the time elapsed after irradiation, was generally unsatisfactory (r = 0.069 at p = 0.599). Similar equations with recovered estimate of the dose and frequency of abnormal chromosomes in a distant period or with all three parameters as variables gave better results (r = 0.686 at p = 0.000000001 and r = 0.542 at p = 0.000008, respectively). PMID:26863777

  12. Health effects models for nuclear power plant accident consequence analysis: Low LET radiation

    SciTech Connect

    Evans, J.S. . School of Public Health)

    1990-01-01

    This report describes dose-response models intended to be used in estimating the radiological health effects of nuclear power plant accidents. Models of early and continuing effects, cancers and thyroid nodules, and genetic effects are provided. Weibull dose-response functions are recommended for evaluating the risks of early and continuing health effects. Three potentially lethal early effects -- the hematopoietic, pulmonary, and gastrointestinal syndromes -- are considered. In addition, models are included for assessing the risks of several nonlethal early and continuing effects -- including prodromal vomiting and diarrhea, hypothyroidism and radiation thyroiditis, skin burns, reproductive effects, and pregnancy losses. Linear and linear-quadratic models are recommended for estimating cancer risks. Parameters are given for analyzing the risks of seven types of cancer in adults -- leukemia, bone, lung, breast, gastrointestinal, thyroid, and other.'' The category, other'' cancers, is intended to reflect the combined risks of multiple myeloma, lymphoma, and cancers of the bladder, kidney, brain, ovary, uterus and cervix. Models of childhood cancers due to in utero exposure are also developed. For most cancers, both incidence and mortality are addressed. The models of cancer risk are derived largely from information summarized in BEIR III -- with some adjustment to reflect more recent studies. 64 refs., 18 figs., 46 tabs.

  13. Dosimetry of ionizing radiation using an iodide/iodate aqueous solution.

    PubMed

    Rahn, Ronald O; Gerstenberg, Henry M; Vavrina, Gerard A

    2002-03-01

    Details of a new aqueous chemical dosimeter consisting of a mixture of KI (0.6 M) and the electron scavenger KIO3 (0.1 M) in 0.01 M borate buffer (pH 9.25) are presented. Exposure was either to gamma sources (137Cs, 60Co) or to linear accelerator (LINAC) radiations (18-MeV electrons, bremsstrahlung X-ray spectrum). G values were obtained for the formation of triiodide; the absorbance at its maximum was then measured at 352 nm. The dose response was linear up to 6000 Gy, the lower limit of detection being approximately 0.25 Gy. G values calculated from the initial slopes of the dose-response curves were 14.1 +/- 0.8 for 137Cs radiations and 13.8 +/- 0.4 and 13.9 +/- 0.8 for the NIST and AFRRI 60Co radiations, respectively. G values obtained for the electron and bremsstrahlung radiations were 12.2 +/- 1.9 and 11.9 +/- 1.8, respectively. The iodide/iodate dosimeter extends the range of detection an order of magnitude both above and below the accepted detection limits of the Fricke dosimeter.

  14. Quality assurance in military medical research and medical radiation accident management.

    PubMed

    Hotz, Mark E; Meineke, Viktor

    2012-08-01

    The provision of quality radiation-related medical diagnostic and therapeutic treatments cannot occur without the presence of robust quality assurance and standardization programs. Medical laboratory services are essential in patient treatment and must be able to meet the needs of all patients and the clinical personnel responsible for the medical care of these patients. Clinical personnel involved in patient care must embody the quality assurance process in daily work to ensure program sustainability. In conformance with the German Federal Government's concept for modern departmental research, the international standard ISO 9001, one of the relevant standards of the International Organization for Standardization (ISO), is applied in quality assurance in military medical research. By its holistic approach, this internationally accepted standard provides an excellent basis for establishing a modern quality management system in line with international standards. Furthermore, this standard can serve as a sound basis for the further development of an already established quality management system when additional standards shall apply, as for instance in reference laboratories or medical laboratories. Besides quality assurance, a military medical facility must manage additional risk events in the context of early recognition/detection of health risks of military personnel on deployment in order to be able to take appropriate preventive and protective measures; for instance, with medical radiation accident management. The international standard ISO 31000:2009 can serve as a guideline for establishing risk management. Clear organizational structures and defined work processes are required when individual laboratory units seek accreditation according to specific laboratory standards. Furthermore, international efforts to develop health laboratory standards must be reinforced that support sustainable quality assurance, as in the exchange and comparison of test results within

  15. DATABASE OF METEOROLOGICAL AND RADIATION MEASUREMENTS MADE IN BELARUS DURING THE FIRST THREE MONTHS FOLLOWING THE CHERNOBYL ACCIDENT

    PubMed Central

    Drozdovitch, Vladimir; Zhukova, Olga; Germenchuk, Maria; Khrutchinsky, Arkady; Kukhta, Tatiana; Luckyanov, Nickolas; Minenko, Victor; Podgaiskaya, Marina; Savkin, Mikhail; Vakulovsky, Sergey; Voillequé, Paul; Bouville, André

    2012-01-01

    Results of all available meteorological and radiation measurements that were performed in Belarus during the first three months after the Chernobyl accident were collected from various sources and incorporated into a single database. Meteorological information such as precipitation, wind speed and direction, and temperature in localities were obtained from meteorological station facilities. Radiation measurements include gamma-exposure rate in air, daily fallout, concentration of different radionuclides in soil, grass, cow’s milk and water as well as total beta-activity in cow’s milk. Considerable efforts were made to evaluate the reliability of the measurements that were collected. The electronic database can be searched according to type of measurement, date, and location. The main purpose of the database is to provide reliable data that can be used in the reconstruction of thyroid doses resulting from the Chernobyl accident. PMID:23103580

  16. Database of meteorological and radiation measurements made in Belarus during the first three months following the Chernobyl accident.

    PubMed

    Drozdovitch, Vladimir; Zhukova, Olga; Germenchuk, Maria; Khrutchinsky, Arkady; Kukhta, Tatiana; Luckyanov, Nickolas; Minenko, Victor; Podgaiskaya, Marina; Savkin, Mikhail; Vakulovsky, Sergey; Voillequé, Paul; Bouville, André

    2013-02-01

    Results of all available meteorological and radiation measurements that were performed in Belarus during the first three months after the Chernobyl accident were collected from various sources and incorporated into a single database. Meteorological information such as precipitation, wind speed and direction, and temperature in localities were obtained from meteorological station facilities. Radiation measurements include gamma-exposure rate in air, daily fallout, concentration of different radionuclides in soil, grass, cow's milk and water as well as total beta-activity in cow's milk. Considerable efforts were made to evaluate the reliability of the measurements that were collected. The electronic database can be searched according to type of measurement, date, and location. The main purpose of the database is to provide reliable data that can be used in the reconstruction of thyroid doses resulting from the Chernobyl accident.

  17. Ion-kill dosimetry

    NASA Technical Reports Server (NTRS)

    Katz, R.; Cucinotta, F. A.; Fromm, M.; Chambaudet, A.

    2001-01-01

    Unanticipated late effects in neutron and heavy ion therapy, not attributable to overdose, imply a qualitative difference between low and high LET therapy. We identify that difference as 'ion kill', associated with the spectrum of z/beta in the radiation field, whose measurement we label 'ion-kill dosimetry'.

  18. Nanoparticle-aided Radiation Therapy: Micro-dosimetry and Evaluation of the Mediators Producing Biological Damage

    NASA Astrophysics Data System (ADS)

    Paudel, Nava Raj

    Radiation therapy has been established as a standard technique for cancer treatment. Advances in nanotechnology have enabled the application of many new approaches in the diagnosis and treatment of cancer. Achievement of selective enhancement in radiation dose deposition within a targeted tumor, while sparing surrounding normal structures, remains a challenge and one of the major objectives of cancer-related research. This objective can be realized by the insertion of high atomic number (Z) materials in the tumor site. Due to their high atomic number (Z=79) and favorable biological compatibility, gold nanoparticles (AuNPs) have been found very promising in this respect. Another candidate material, platinum (Z=78), offering very similar radiation interaction properties to gold and exhibiting additional cytotoxic effects, has been exploited in chemotherapeutic agents for a long time. We explore the radiation effects near the interface of gold and platinum with tissue under a wide range of energies with Monte Carlo (MC) simulations. Our studies show that AuNPs and PtNPs (platinum nanoparticles) can offer a useful dose enhancement effect even in high energy radiotherapy beams, which can be important when critical structures are located close to the tumor. Our MC calculated dose enhancement increase of about 50% due to the removal of the flattening filter from the path of the photon beam of Varian TrueBeam accelerator suggests that flattening-filter-free beams are better suited for nanoparticle-aided radiation therapy. Also, the increase in dose enhancement with the tumor depth suggests that nanopartcle-aided radiation therapy can yield a better outcome while treating deep-seated tumors. Experimental microdosimetry is a non-trivial task, demanding detectors with small sensitive volumes to achieve a high spatial resolution. We have developed a microdosimetry technique utilizing an inexpensive in-house-built photodetector for the measurement of dose in a narrow high dose

  19. Dosimetry in steep dose-rate gradient radiation fields: A challenge in clinical applications

    SciTech Connect

    Massillon-JL, G.

    2010-12-07

    The fundamental goal of radiotherapy is to reduce the damage to normal tissue and optimize the dose to the tumor with an associated high probability of cure. Because of this, an accurate and precise knowledge of the radiation dose distribution delivered around the tumor volume during radiotherapy treatments such as stereotactic radiosurgery, intensity modulated radiotherapy or brachytherapy with low-energy X-ray and beta particle sources is of great importance. However, in each of these radiation fields, there exists a steep dose-rate gradient which makes it very difficult to perform accurate dose measurements. In this work, the physics phenomena involved in the energy absorption for each of these situations are discussed, and a brief revision of what the Medical Physics community is doing is presented.

  20. Dosimetry in steep dose-rate gradient radiation fields: A challenge in clinical applications

    NASA Astrophysics Data System (ADS)

    Massillon-JL, G.

    2010-12-01

    The fundamental goal of radiotherapy is to reduce the damage to normal tissue and optimize the dose to the tumor with an associated high probability of cure. Because of this, an accurate and precise knowledge of the radiation dose distribution delivered around the tumor volume during radiotherapy treatments such as stereotactic radiosurgery, intensity modulated radiotherapy or brachytherapy with low-energy X-ray and beta particle sources is of great importance. However, in each of these radiation fields, there exists a steep dose-rate gradient which makes it very difficult to perform accurate dose measurements. In this work, the physics phenomena involved in the energy absorption for each of these situations are discussed, and a brief revision of what the Medical Physics community is doing is presented.

  1. Improved Radiation Dosimetry/Risk Estimates to Facilitate Environmental Management of Plutonium-Contaminated Sites

    SciTech Connect

    Scott, Bobby R.; Tokarskaya, Zoya B.; Zhuntova, Galina V.; Osovets, Sergey V.; Syrchikov, Victor A., Belyaeva, Zinaida D.

    2007-12-14

    This report summarizes 4 years of research achievements in this Office of Science (BER), U.S. Department of Energy (DOE) project. The research described was conducted by scientists and supporting staff at Lovelace Respiratory Research Institute (LRRI)/Lovelace Biomedical and Environmental Research Institute (LBERI) and the Southern Urals Biophysics Institute (SUBI). All project objectives and goals were achieved. A major focus was on obtaining improved cancer risk estimates for exposure via inhalation to plutonium (Pu) isotopes in the workplace (DOE radiation workers) and environment (public exposures to Pu-contaminated soil). A major finding was that low doses and dose rates of gamma rays can significantly suppress cancer induction by alpha radiation from inhaled Pu isotopes. The suppression relates to stimulation of the body's natural defenses, including immunity against cancer cells and selective apoptosis which removes precancerous and other aberrant cells.

  2. Rural areas affected by the Chernobyl accident: radiation exposure and remediation strategies.

    PubMed

    Jacob, P; Fesenko, S; Bogdevitch, I; Kashparov, V; Sanzharova, N; Grebenshikova, N; Isamov, N; Lazarev, N; Panov, A; Ulanovsky, A; Zhuchenko, Y; Zhurba, M

    2009-12-15

    Main objectives of the present work were to develop an internationally agreed methodology for deriving optimized remediation strategies in rural areas that are still affected by the Chernobyl accident, and to give an overview of the radiological situation in the three affected countries, Belarus, Russia and Ukraine. Study settlements were defined by having in 2004 less than 10,000 inhabitants and official dose estimates exceeding 1 mSv. Data on population, current farming practices, contamination of soils and foodstuffs, and remedial actions previously applied were collected for each of such 541 study settlements. Calculations of the annual effective dose from internal radiation were validated with extensive data sets on whole body counter measurements. According to our calculations for 2004, in 290 of the study settlements the effective dose exceeded 1 mSv, and the collective dose in these settlements amounted to about 66 person-Sv. Six remedial actions were considered: radical improvement of grassland, application of ferrocyn to cows, feeding pigs with uncontaminated fodder before slaughter, application of mineral fertilizers for potato fields, information campaign on contaminated forest produce, and replacement of contaminated soil in populated areas by uncontaminated soil. Side effects of the remedial actions were quantified by a 'degree of acceptability'. Results are presented for two remediation strategies, namely, Strategy 1, in which the degree of acceptability was given a priority, and Remediation Strategy 2, in which remedial actions were chosen according to lowest costs per averted dose only. Results are highly country-specific varying from preference for soil replacement in populated areas in Belarus to preference for application of ferrocyn to cows in Ukraine. Remedial actions in 2010 can avert a large collective dose of about 150 person-Sv (including averted doses, which would be received in the following years). Nevertheless, the number of

  3. The UF Family of hybrid phantoms of the pregnant female for computational radiation dosimetry

    NASA Astrophysics Data System (ADS)

    Maynard, Matthew R.; Long, Nelia S.; Moawad, Nash S.; Shifrin, Roger Y.; Geyer, Amy M.; Fong, Grant; Bolch, Wesley E.

    2014-08-01

    Efforts to assess in utero radiation doses and related quantities to the developing fetus should account for the presence of the surrounding maternal tissues. Maternal tissues can provide varying levels of protection to the fetus by shielding externally-emitted radiation or, alternatively, can become sources of internally-emitted radiation following the biokinetic uptake of medically-administered radiopharmaceuticals or radionuclides located in the surrounding environment—as in the case of the European Union’s SOLO project (Epidemiological Studies of Exposed Southern Urals Populations). The University of Florida had previously addressed limitations in available computational phantom representation of the developing fetus by constructing a series of hybrid computational fetal phantoms at eight different ages and three weight percentiles. Using CT image sets of pregnant patients contoured using 3D-DOCTORTM, the eight 50th percentile fetal phantoms from that study were systematically combined in RhinocerosTM with the UF adult non-pregnant female to yield a series of reference pregnant female phantoms at fetal ages 8, 10, 15, 20, 25, 30, 35 and 38 weeks post-conception. Deformable, non-uniform rational B-spline surfaces were utilized to alter contoured maternal anatomy in order to (1) accurately position and orient each fetus and surrounding maternal tissues and (2) match target masses of maternal soft tissue organs to reference data reported in the literature.

  4. Aircrew dosimetry using the Predictive Code for Aircrew Radiation Exposure (PCAIRE).

    PubMed

    Lewis, B J; Bennett, L G I; Green, A R; Butler, A; Desormeaux, M; Kitching, F; McCall, M J; Ellaschuk, B; Pierre, M

    2005-01-01

    During 2003, a portable instrument suite was used to conduct cosmic radiation measurements on 49 jet-altitude flights, which brings the total number of in-flight measurements by this research group to over 160 flights since 1999. From previous measurements, correlations have been developed to allow for the interpolation of the dose-equivalent rate for any global position, altitude and date. The result was a Predictive Code for Aircrew Radiation Exposure (PCAIRE), which has since been improved. This version of the PCAIRE has been validated against the integral route dose measurements made at commercial aircraft altitudes during the 49 flights. On most flights, the code gave predictions that agreed to the measured data (within +/- 25%), providing confidence in the use of PCAIRE to predict aircrew exposure to galactic cosmic radiation. An empirical correlation, based on ground-level neutron monitoring data, has also been developed for the estimation of aircrew exposure from solar energetic particle (SEP) events. This model has been used to determine the significance of SEP exposure on a theoretical jet altitude flight during GLE 42.

  5. Characterisation of the thermoluminescence (TL) properties of tailor-made Ge-doped silica glass fibre for applications in medical radiation therapy dosimetry

    NASA Astrophysics Data System (ADS)

    Zahaimi, N. A.; Zin, H.; Mahdiraji, G. A.; Rahman, A. L. Abdul; Bradley, D. A.; Rahman, A. T. Abdul

    2014-11-01

    We have investigated the characterisation of new fabricated material Ge doped silica glass thermoluminescence TL dosimeter (Photonic Research Centre, University of Malaya) for medical radiation dosimetry at therapy energy. Previously, the dosimeter has been studied to provide ideal dosimetry system, suitable to ensure an accurate delivery of radiation doses to tumour tissue while minimising the amount of radiation administrated to healthy tissue. Both energies of photon and electron were used in this experiment for a dose range of 1 to 5 Gy. The various sizes of core diameter Ge doped silica glass (120, 241, 362, 483 and 604 μm) were exposed by using linear accelerator at Pantai Medical Centre. For both energies, the optical fibres were found to produce a flat response to a fixed photon and electron doses to within 4% (S.D) of the mean of the TL distribution. In terms of dose response, the fibres provide linear response over the range investigated, from a fraction of 1-5 Gy. The finding shows 120 μm fibres have 1.82 greater dose response than 604 pm fibres irradiated at 6 MV photon with a fixed dose of 3 Gy. While for electron energy 12 MeV, the response shows 120 μm fibres have 1.58 greater dose response compared to 604 μm fibres. The good responses are suitable to make these tailor-made doped silica fibres a promising TL material for use as a dosimetric system in medical radiation therapy.

  6. Radiation dosimetry of N-([11C]methyl)benperidol as determined by whole-body PET imaging of primates

    PubMed Central

    Antenor-Dorsey, Jo Ann V.; Laforest, Richard; Moerlein, Stephen M.; Videen, Tom O.

    2010-01-01

    Purpose N-([11C]methyl)benperidol ([11C]NMB) can be used for positron emission tomography (PET) measurements of D2-like dopamine receptor binding in vivo. We report the absorbed radiation dosimetry of i.v.-administered 11C-NMB, a critical step before applying this radioligand to imaging studies in humans. Materials and methods Whole-body PET imaging with a CTI/Siemens ECAT 953B scanner was done in a male and a female baboon. After i.v. injection of 444–1221 MBq of 11C-NMB, sequential images taken from the head to the pelvis were collected for 3 h. Volumes of interest (VOIs) were identified that entirely encompassed small organs (whole brain, striatum, eyes, and myocardium). Large organs (liver, lungs, kidneys, lower large intestine, and urinary bladder) were sampled by drawing representative regions within the organ volume. Time–activity curves for each VOI were extracted from the PET, and organ residence times were calculated by analytical integration of a multi-exponential fit of the time–activity curves. Human radiation doses were estimated using OLINDA/EXM 1.0 and the standard human model. Results Highest retention was observed in the blood and liver, each with total residence times of 1.5 min. The highest absorbed radiation doses were to the heart (10.5 mGy/kBq) and kidney (9.19 mGy/kBq), making these the critical organs for [11C]NMB. A heart absorption of 50 mGy would result from an injected dose of 4,762 MBq [11C]NMB. Conclusions Thus, this study suggests that up to 4,762 MBq of [11C]NMB can be safely administered to human subjects for PET studies. Total body dose and effective dose for [11C] NMB are 2.82 mGy/kBq and 3.7 mSv/kBq, respectively. PMID:18071701

  7. DEVELOPMENT OF A NATIONAL EMERGENCY PLAN FOR MEDICAL DIAGNOSTICS AND THERAPY OF DETERMINISTIC EFFECTS AFTER RADIATION ACCIDENTS.

    PubMed

    Ziegler, Andreas

    2016-09-01

    The focus of nuclear emergency planning in Austria has been so far on mitigating effects of widespread contamination (e.g. after NPP accidents); however, these plans did not contain provisions on the medical management of an acute radiation syndrome. To close this gap, a 'Medical Radiation Emergency Plan' was created in 2009 and 2011. This paper describes the development of this plan (including the selection of consulted guidance) as well as its structure and main propositions and closes with an outlook on probable enhancements for the second edition.

  8. Little impact of tsunami-stricken nuclear accident on awareness of radiation dose of cardiac computed tomography: A questionnaire study

    PubMed Central

    2013-01-01

    Background With the increased use of cardiac computed tomography (CT), radiation dose remains a major issue, although physicians are trying to reduce the substantial risks associated with use of this diagnostic tool. This study was performed to investigate recognition of the level of radiation exposure from cardiac CT and the differences in the level of awareness of radiation before and after the Fukushima nuclear plant accident. Methods We asked 30 physicians who were undergoing training in internal medicine to determine the equivalent doses of radiation for common radiological examinations when a normal chest X-ray is accepted as one unit; questions about the absolute radiation dose of cardiac CT data were also asked. Results According to the results, 86.6% of respondents believed the exposure to be 1 mSv at most, and 93.3% thought that the exposure was less than that of 100 chest X-rays. This finding indicates that their perceptions were far lower than the actual amounts. Even after the occurrence of such a large nuclear disaster in Fukushima, there were no significant differences in the same subjects’ overall awareness of radiation amounts. Conclusions Even after such a major social issue as the Fukushima nuclear accident, the level of awareness of the accurate radiation amount used in 64-channel multidetector CT (MDCT) by clinical physicians who order this test was not satisfactory. Thus, there is a need for the development of effective continuing education programs to improve awareness of radiation from ionizing radiation devices, including cardiac CT, and emphasis on risk-benefit evaluation based on accurate knowledge during medical training. PMID:23631688

  9. Dosimetry with diamond detectors

    NASA Astrophysics Data System (ADS)

    Gervino, G.; Marino, C.; Silvestri, F.; Lavagno, A.; Truc, F.

    2010-05-01

    In this paper we present the dosimetry analysis in terms of stability and repeatability of the signal and dose rate dependence of a synthetic single crystal diamond grown by Chemical Vapor Deposition (CVD) technique. The measurements carried out by 5 MeV X-ray photons beam show very promising results, even if the dose rate detector response points out that the charge trapping centers distribution is not uniform inside the crystal volume. This handicap that affects the detectors performances, must be ascribed to the growing process. Synthetic single crystal diamonds could be a valuable alternative to air ionization chambers for quality beam control and for intensity modulated radiation therapy beams dosimetry.

  10. Radiation risk assessment in neonatal radiographic examinations of the chest and abdomen: a clinical and Monte Carlo dosimetry study

    NASA Astrophysics Data System (ADS)

    Makri, T.; Yakoumakis, E.; Papadopoulou, D.; Gialousis, G.; Theodoropoulos, V.; Sandilos, P.; Georgiou, E.

    2006-10-01

    Seeking to assess the radiation risk associated with radiological examinations in neonatal intensive care units, thermo-luminescence dosimetry was used for the measurement of entrance surface dose (ESD) in 44 AP chest and 28 AP combined chest-abdominal exposures of a sample of 60 neonates. The mean values of ESD were found to be equal to 44 ± 16 µGy and 43 ± 19 µGy, respectively. The MCNP-4C2 code with a mathematical phantom simulating a neonate and appropriate x-ray energy spectra were employed for the simulation of the AP chest and AP combined chest-abdominal exposures. Equivalent organ dose per unit ESD and energy imparted per unit ESD calculations are presented in tabular form. Combined with ESD measurements, these calculations yield an effective dose of 10.2 ± 3.7 µSv, regardless of sex, and an imparted energy of 18.5 ± 6.7 µJ for the chest radiograph. The corresponding results for the combined chest-abdominal examination are 14.7 ± 7.6 µSv (males)/17.2 ± 7.6 µSv (females) and 29.7 ± 13.2 µJ. The calculated total risk per radiograph was low, ranging between 1.7 and 2.9 per million neonates, per film, and being slightly higher for females. Results of this study are in good agreement with previous studies, especially in view of the diversity met in the calculation methods.

  11. The [14C-N-methyl]-erythromycin breath test dosimetry complies with the French regulations for radiation safety.

    PubMed

    Salvat, Cécile; Mouly, Stéphane; Rizzo-Padoin, Nathalie; Knellwolf, Anne-Laure; Simoneau, Guy; Duet, Michèle; Nataf, Valérie; Bailliart, Olivier; Bergmann, Jean-François

    2003-06-01

    The [14C-N-methyl]-erythromycin breath test (14C-ERMBT) is one of the most valuable probes for liver cytochrome P450-3A4 activity in humans. In order to extend the use of this test in France, we herein provide safety data regarding either patient dosimetry or worker exposure to [14C-N-methyl]-erythromycin. In order to determine the maximum radiation exposure for patient and nuclear medicine technician following one intravenous 14C-ERMBT [111 kiloBequerel (kBq)], we have used the dosimetric data gathered in animal studies and extrapolated to humans using a weight-based method, approximate data provided by the French Society of Radioprotection and erythromycin pharmacokinetics in humans, considering always the worst conditions for the patient and worker exposure determination. The radioactivity administered to a patient after one 14C-ERMBT was equal to 108.8 kBq (i.e. 98% of the total radioactivity in the 14C-erythromycin vial) leading to a patient effective dose of 20 microsievert (microSv) and a maximum effective dose after 14CO2 inhalation by the exposed worker of 16 microSv compared with a mean individual annual effective dose from natural and artificial radioactivity exposure of 3500 microSv in France. The 14C-ERMBT is safe and complies with the European regulations regarding the administration of 14C-labelled compounds in humans. It can therefore be used in clinical research in France without any particular safety requirement.

  12. Dosimetry in brain tumor phantom at 15 MV 3D conformal radiation therapy

    PubMed Central

    2013-01-01

    Glioblastoma multiforme (GBM) is the most common, aggressive, highly malignant and infiltrative of all brain tumors with low rate of control. The main goal of this work was to evaluate the spatial dose distribution into a GBM simulator inside a head phantom exposed to a 15 MV 3D conformal radiation therapy in order to validate internal doses. A head and neck phantom developed by the Ionizing Radiation Research Group (NRI) was used on the experiments. Such phantom holds the following synthetic structures: brain and spinal cord, skull, cervical and thoracic vertebrae, jaw, hyoid bone, laryngeal cartilages, head and neck muscles and skin. Computer tomography (CT) of the simulator was taken, capturing a set of contrasted references. Therapy Radiation planning (TPS) was performed based on those CT images, satisfying a 200 cGy prescribed dose split in three irradiation fields. The TPS assumed 97% of prescribed dose cover the prescribed treatment volume (PTV). Radiochromic films in a solid water phantom provided dose response as a function of optical density. Spatial dosimetric distribution was generated by radiochromic film samples at coronal, sagittal-anterior and sagittal-posterior positions, inserted into tumor simulator and brain. The spatial dose profiles held 70 to 120% of the prescribed dose. In spite of the stratified profile, as opposed to the smooth dose profile from TPS, the tumor internal doses were within a 5% deviation from 214.4 cGy evaluated by TPS. 83.2% of the points with a gamma value of less than 1 (3%/3mm) for TPS and experimental values, respectively. At the tumor, measured at coronal section, a few dark spots in the film caused the appearance of outlier points in 13-15% of dose deviation percentage. And, as final conclusion, such dosimeter choice and the physical anthropomorphic and anthropometric phantom provided an efficient method for validating radiotherapy protocols. PMID:23829593

  13. US plant and radiation dosimetry experiments flown on the Soviet satellite Cosmos 1129

    NASA Technical Reports Server (NTRS)

    Heinrich, M. R. (Editor); Souza, K. A. (Editor)

    1981-01-01

    Experiments included: 30 young male Wistar SPF rats used for wide range physiological studies; experiments with plants, fungi, insects, and mammalian tissue cultures; radiation physics experiments; a heat convection study; a rat embryology experiment in which an attempt was made to breed 2 male and 5 female rats during the flight; and fertile quail eggs used to determine the effects of spaceflight on avian embryogenesis. Specimens for US experiments were initially prepared at the recovery site or in Moscow and transferred to US laboratories for complete analyses. An overview of the mission focusing on preflight, on orbit, and postflight activities pertinent to the fourteen US experiments aboard Cosmos 1129 is presented.

  14. Dosimetry of secondary cosmic radiation up to an altitude of 30 km.

    PubMed

    Wissmann, F; Burda, O; Khurana, S; Klages, T; Langner, F

    2014-10-01

    Dosimetric measurements in the field of secondary cosmic radiation were extensively made during the last years. Since the majority of these measurements were performed on-board passenger aircraft at altitudes between 10 and 12 km, measurements at higher altitudes are desirable for the verification of the legal dose assessment procedures for aircrew. A simple solution is to use a high-altitude balloon that reaches altitudes as high as 30 km. In this work, it is shown that the dose rate profile up to 30 km can be measured with acceptable uncertainties using a Si-detector. PMID:24345463

  15. Dosimetry of secondary cosmic radiation up to an altitude of 30 km.

    PubMed

    Wissmann, F; Burda, O; Khurana, S; Klages, T; Langner, F

    2014-10-01

    Dosimetric measurements in the field of secondary cosmic radiation were extensively made during the last years. Since the majority of these measurements were performed on-board passenger aircraft at altitudes between 10 and 12 km, measurements at higher altitudes are desirable for the verification of the legal dose assessment procedures for aircrew. A simple solution is to use a high-altitude balloon that reaches altitudes as high as 30 km. In this work, it is shown that the dose rate profile up to 30 km can be measured with acceptable uncertainties using a Si-detector.

  16. Dosimetry of UV radiation with special respect to presence of photosensitizers or other chemical agents

    NASA Astrophysics Data System (ADS)

    Ronto, Gyorgyi; Csik, Gabriella; Gaspar, S.

    1994-02-01

    A method has been developed for measuring the biologically effective dose (BED) of solar radiation. The method applies phage T7 as a biosensor in a monitoring system. The work presents a series of dose measurements caused by direct and global irradiation. Comparisons are made of the results obtained in the same time in different places in Hungary in 1992 and 1993. A doubling of the measured BED was found which can not be explained with the ozone depletion only. An interpretation of phage T7 dose as well as transformation of the results into MED are presented. The influence of the photosensitization as an additive damage is discussed as well.

  17. US plant and radiation dosimetry experiments flown on the soviet satellite COSMOS 1129. Final report

    SciTech Connect

    Heinrich, M.R.; Souza, K.A.

    1981-05-01

    Experiments included: 30 young male Wistar SPF rats used for wide range physiological studies Kosmos Satellites experiments with plants, fungi, insects, and mammalian tissue cultures; radiation physics experiments; a heat convection study; a rat embryology experiment in which an attempt was made to breed 2 male and 5 female rats during the flight; and fertile quail eggs used to determine the effects of spaceflight on avian embryogenesis. Specimens for US experiments were initially prepared at the recovery site or in Moscow and transferred to US laboratories for complete analyses. An overview of the mission focusing on preflight, on orbit, and postflight activities pertinent to the fourteen US experiments aboard Cosmos 1129 is presented.

  18. Duality of solar UV-B radiation and relevant dosimetry: vitamin D synthesis versus skin erythema

    NASA Astrophysics Data System (ADS)

    Terenetskaya, Irina P.

    2003-06-01

    Solar ultraviolet radiation (UVR) gives rise to beneficial or adverse health effects depending on the dose. Excessive UV exposures are associated with acute and chronic health effect but in appropriate doses UV sunlight is advisable. Important biological function of UVR is initiation of endogenous synthesis of vitamin D in human skin. A useful method based on an in vitro model of vitamin D synthesis ('D-dosimeter') has been specially developed to measure the vitamin D synthetic capacity of sunlight in situ. For the first time laboratory and field tests have been performed to link commonly used erythemal units (MEDs) and previtamin D accumulation.

  19. Radiation dosimetry for the adult female and fetus from iodine-131 administration in hyperthyroidism

    SciTech Connect

    Stabin, M.G.; Watson, E.E.; Marcus, C.S.; Salk, R.D. )

    1991-05-01

    Through a study of the iodine kinetics of 127 patients, we have developed radiation dose estimates to major organs and the fetus for patients with varying degrees of hyperthyroidism. We observed a negative correlation between maximum thyroid uptake and biologic half-time of iodine in the thyroid and used this correlation to predict the biologic half-time at fixed values of maximum thyroid uptake. Dose estimates to the bladder, gonads, marrow, thyroid, uterus, and whole body were estimated for maximum thyroid uptakes from 20% to 100%. Bladder dose varied from 0.6 to 1.0 mGy/MBq and dose to the uterus varied from 0.036 to 0.063 mGy/MBq under different model assumptions. Dose estimates to the fetus and fetal thyroid were approximated at all stages of pregnancy. Average fetal dose was a maximum between 0 and 2 mo of pregnancy, with the maximum ranging from 0.048 mGy/MBq to 0.083 mGy/MBq, depending on model assumptions. Some radiation risks for irradiation of the fetus and the fetal thyroid are discussed.

  20. Ultraviolet radiation (UVR) dosimetry system and the use of Ge-doped silica optical fibres

    NASA Astrophysics Data System (ADS)

    Abdul Rahman, Ahmad Taufek; Abu Bakar, Noor Khairunnisa; Chandra Paul, Mukul; Bradley, D. A.

    2014-11-01

    Previous studies have shown that over exposure to ultraviolet radiation (UVR), either from sunlight or artificial sources, can cause severe biological effects including cataracts, photokeratitis and skin cancer. In this respect, there exists the need to introduce a sensitive UV dosimetric material capable of measuring radiation dose to high accuracy in order to deliver UVR safely and efficiently. Present study has focussed on the investigation of the potential thermoluminescent (TL) sensitivity of commercially available germanium (Ge)-doped silica (SiO2) optical fibres subjected to UVR. The main interest of this study is to find out whether these doped SiO2 optical fibres can be used as a sensible integrator of environmental UV exposures. In the present study, commercially available Ge-doped SiO2 optical fibres have been used with a core diameter of 11 μm (CorActive, Canada), 23 μm (Central Glass and Ceramic Research Institute Kolkata, India) and 50 μm (Central Glass and Ceramic Research Institute Kolkata, India) and a cladding diameter of 125±0.1 μm, irradiated over a wide range of UV dose. Results have shown that these fibres exhibit a linear dose response (with correlation coefficient better than 0.9852). The 50 μm fibre produces greater TL response than that obtained for 11- and 23 μm fibres. The TL results are compared with that of the well-established TL dosimeter material lithium fluoride.

  1. Reassessment of atomic bomb radiation dosimetry in Hiroshima and Nagasaki: proceedings

    SciTech Connect

    Not Available

    1983-06-01

    The presentations at this workshop are the first of a series of joint efforts, among knowledgeable scientists in Japan and the United States under RERF auspices, directed toward reassessing the dose of ionizing radiation received by survivors of the atomic bombs dropped on Hiroshima and Nagasaki. The last previous dose estimate revisions occurred in 1965 and since that time new technology and understanding have become available for this purpose. It is the hope of RERF that the collaboration represented by this workshop and the following day of free discussion among the participating scientists will establish a procedure which will ensure that the resulting dose estimates are as accurate as possible. Acceptance of the resulting estimates by the scientific communities of both nations is our ultimate goal. This first workshop has concentrated on presenting current evidence concerning the yield of the two weapons, the spectra of the radiations from them, their transport through air, and various in situ measurements of the resulting excitation of materials on the ground (insulators, roof tiles, iron rods, etc.) which can be used to check the theoretical calculations.

  2. Public health activities for mitigation of radiation exposures and risk communication challenges after the Fukushima nuclear accident.

    PubMed

    Shimura, Tsutomu; Yamaguchi, Ichiro; Terada, Hiroshi; Robert Svendsen, Erik; Kunugita, Naoki

    2015-05-01

    Herein we summarize the public health actions taken to mitigate exposure of the public to radiation after the Fukushima accident that occurred on 11 March 2011 in order to record valuable lessons learned for disaster preparedness. Evacuations from the radiation-affected areas and control of the distribution of various food products contributed to the reduction of external and internal radiation exposure resulting from the Fukushima incident. However, risk communication is also an important issue during the emergency response effort and subsequent phases of dealiing with a nuclear disaster. To assist with their healing process, sound, reliable scientific information should continue to be disseminated to the radiation-affected communities via two-way communication. We will describe the essential public health actions following a nuclear disaster for the early, intermediate and late phases that will be useful for radiological preparedness planning in response to other nuclear or radiological disasters.

  3. Public health activities for mitigation of radiation exposures and risk communication challenges after the Fukushima nuclear accident

    PubMed Central

    Shimura, Tsutomu; Yamaguchi, Ichiro; Terada, Hiroshi; Robert Svendsen, Erik; Kunugita, Naoki

    2015-01-01

    Herein we summarize the public health actions taken to mitigate exposure of the public to radiation after the Fukushima accident that occurred on 11 March 2011 in order to record valuable lessons learned for disaster preparedness. Evacuations from the radiation-affected areas and control of the distribution of various food products contributed to the reduction of external and internal radiation exposure resulting from the Fukushima incident. However, risk communication is also an important issue during the emergency response effort and subsequent phases of dealiing with a nuclear disaster. To assist with their healing process, sound, reliable scientific information should continue to be disseminated to the radiation-affected communities via two-way communication. We will describe the essential public health actions following a nuclear disaster for the early, intermediate and late phases that will be useful for radiological preparedness planning in response to other nuclear or radiological disasters. PMID:25862700

  4. Public health activities for mitigation of radiation exposures and risk communication challenges after the Fukushima nuclear accident.

    PubMed

    Shimura, Tsutomu; Yamaguchi, Ichiro; Terada, Hiroshi; Robert Svendsen, Erik; Kunugita, Naoki

    2015-05-01

    Herein we summarize the public health actions taken to mitigate exposure of the public to radiation after the Fukushima accident that occurred on 11 March 2011 in order to record valuable lessons learned for disaster preparedness. Evacuations from the radiation-affected areas and control of the distribution of various food products contributed to the reduction of external and internal radiation exposure resulting from the Fukushima incident. However, risk communication is also an important issue during the emergency response effort and subsequent phases of dealiing with a nuclear disaster. To assist with their healing process, sound, reliable scientific information should continue to be disseminated to the radiation-affected communities via two-way communication. We will describe the essential public health actions following a nuclear disaster for the early, intermediate and late phases that will be useful for radiological preparedness planning in response to other nuclear or radiological disasters. PMID:25862700

  5. A radiation dosimetry model for radiolabeled monoclonal antibodies: Indium-111-labeled B72. 3-GYK-DTPA for colorectal cancer

    SciTech Connect

    Wilson, L.A.

    1990-01-01

    A foundation was developed for a dosimetry methodology that could be used to calculate absorbed doses in target and nontarget tissues using uniformly and nonuniformly distributed activity. In this methodology, a dosimetry model was developed which consisted of three independent models: (1) the SPECT Model, (2) the Monte Carlo Model, and (3) the Dosimetry Model. The SPECT Model uses Single-Photon Emission Computed Tomography (SPECT) images to determine the volume and radioactive uptake. A computer program was written to automatically read and analyze SPECT images. This program uses an edge detection method to determine the volume. Voxel elements within the identified volume are used to calculate the activity concentrations. THe Monte Carlo Model uses a monte carlso simulation method and results of the SPECT Model to calculate the fraction of photon energy deposited in target and nontarget tissues. The Dosimetry Model combines the results of the SPECT and Monte Carlo Models to determine the absorbed dose in target and nontarget tissues. Several phantom studies were conducted to verify the ability of the Dosimetry Model to evaluate organ and tumor uptake, sizes, and to calculate absorbed doses. Comparisons were made between the Dosimetry Model, other calculational methods (MIRDOSE2, Geometric Factor Method, MIRD Pamphlet No. 3), and TLD measurements. For diagnostic activity doses, the SPECT Model was found to calculate organ volumes of the order of 1,000 ml to within fifteen percent of the actual volumes but it failed to accurately calculate organ volumes of 200 ml or less. No meaningful relationship was found between the actual and SPECT measured activity concentrations. The Dosimetry Model agreed within 12% when compared with the Geometric Factor Method and the MIRD Pamphlet No. 3 results using homogeneously and heterogeneously distributed [sup 111]In. The TLD measurements were within 30% at most of the other methods.

  6. Pediatric radiation dosimetry for positron-emitting radionuclides using anthropomorphic phantoms

    SciTech Connect

    Xie, Tianwu; Bolch, Wesley E.; Lee, Choonsik; Zaidi, Habib

    2013-10-15

    Purpose: Positron emission tomography (PET) plays an important role in the diagnosis, staging, treatment, and surveillance of clinically localized diseases. Combined PET/CT imaging exhibits significantly higher sensitivity, specificity, and accuracy than conventional imaging when it comes to detecting malignant tumors in children. However, the radiation dose from positron-emitting radionuclide to the pediatric population is a matter of concern since children are at a particularly high risk when exposed to ionizing radiation.Methods: The authors evaluate the absorbed fractions and specific absorbed fractions (SAFs) of monoenergy photons/electrons as well as S-values of 9 positron-emitting radionuclides (C-11, N-13, O-15, F-18, Cu-64, Ga-68, Rb-82, Y-86, and I-124) in 48 source regions for 10 anthropomorphic pediatric hybrid models, including the reference newborn, 1-, 5-, 10-, and 15-yr-old male and female models, using the Monte Carlo N-Particle eXtended general purpose Monte Carlo transport code.Results: The self-absorbed SAFs and S-values for most organs were inversely related to the age and body weight, whereas the cross-dose terms presented less correlation with body weight. For most source/target organ pairs, Rb-82 and Y-86 produce the highest self-absorbed and cross-absorbed S-values, respectively, while Cu-64 produces the lowest S-values because of the low-energy and high-frequency of electron emissions. Most of the total self-absorbed S-values are contributed from nonpenetrating particles (electrons and positrons), which have a linear relationship with body weight. The dependence of self-absorbed S-values of the two annihilation photons varies to the reciprocal of 0.76 power of the mass, whereas the self-absorbed S-values of positrons vary according to the reciprocal mass.Conclusions: The produced S-values for common positron-emitting radionuclides can be exploited for the assessment of radiation dose delivered to the pediatric population from various PET

  7. Lessons learned from Fukushima Daiichi nuclear power plant accident: efficient education items of radiation safety for general public.

    PubMed

    Ohno, K; Endo, K

    2015-07-01

    The Fukushima Daiichi nuclear power plant (FNP-1) accident, while as tragic as the tsunami, was a man-made disaster created by the ignorance of the effects of radiation and radioactive materials. Therefore, it is important that all specialists in radiation protection in medicine sympathize with the anxiety of the general public regarding the harmful effects of radiation and advise people accordingly. All questions and answers were collected related to inquiries from the general public that were posted to reliable websites, including those of the government and radiation-related organizations, from March 2011 to November 2012. The questions were summarized and classified by similarity of content. (1) The total number of questions is 372. The content was broadly classified into three categories: inquiries for radiation-related knowledge and about health effects and foods. The questions asked to obtain radiation-related knowledge were the most common, accounting for 38 %. Thirty-six percentage of the questions were related to health effects, and 26 % involved foods, whereas 18 % of the questions were related to children and pregnancy. (2) The change over time was investigated in 290 questions for which the time of inquiry was known. Directly after the earthquake, the questions were primarily from people seeking radiation-related knowledge. Later, questions related to health effects increased. The anxiety experienced by residents following the nuclear accident was caused primarily by insufficient knowledge related to radiation, concerns about health effects and uncertainties about food and water safety. The development of educational materials focusing on such content will be important for risk communication with the general public in countries with nuclear power plants. Physicians and medical physicist should possess the ability to respond to questions such as these and should continue with medical examinations and treatments in a safe and appropriate manner. PMID

  8. Lessons learned from Fukushima Daiichi nuclear power plant accident: efficient education items of radiation safety for general public.

    PubMed

    Ohno, K; Endo, K

    2015-07-01

    The Fukushima Daiichi nuclear power plant (FNP-1) accident, while as tragic as the tsunami, was a man-made disaster created by the ignorance of the effects of radiation and radioactive materials. Therefore, it is important that all specialists in radiation protection in medicine sympathize with the anxiety of the general public regarding the harmful effects of radiation and advise people accordingly. All questions and answers were collected related to inquiries from the general public that were posted to reliable websites, including those of the government and radiation-related organizations, from March 2011 to November 2012. The questions were summarized and classified by similarity of content. (1) The total number of questions is 372. The content was broadly classified into three categories: inquiries for radiation-related knowledge and about health effects and foods. The questions asked to obtain radiation-related knowledge were the most common, accounting for 38 %. Thirty-six percentage of the questions were related to health effects, and 26 % involved foods, whereas 18 % of the questions were related to children and pregnancy. (2) The change over time was investigated in 290 questions for which the time of inquiry was known. Directly after the earthquake, the questions were primarily from people seeking radiation-related knowledge. Later, questions related to health effects increased. The anxiety experienced by residents following the nuclear accident was caused primarily by insufficient knowledge related to radiation, concerns about health effects and uncertainties about food and water safety. The development of educational materials focusing on such content will be important for risk communication with the general public in countries with nuclear power plants. Physicians and medical physicist should possess the ability to respond to questions such as these and should continue with medical examinations and treatments in a safe and appropriate manner.

  9. Cherenkov radiation dosimetry in water tanks - video rate imaging, tomography and IMRT & VMAT plan verification

    NASA Astrophysics Data System (ADS)

    Pogue, Brian W.; Glaser, Adam K.; Zhang, Rongxiao; Gladstone, David J.

    2015-01-01

    This paper presents a survey of three types of imaging of radiation beams in water tanks for comparison to dose maps. The first was simple depth and lateral profile verification, showing excellent agreement between Cherenkov and planned dose, as predicted by the treatment planning system for a square 5cm beam. The second approach was 3D tomography of such beams, using a rotating water tank with camera attached, and using filtered backprojection for the recovery of the 3D volume. The final presentation was real time 2D imaging of IMRT or VMAT treatments in a water tank. In all cases the match to the treatment planning system was within what would be considered acceptable for clinical medical physics acceptance.

  10. Radiation dosimetry at CT fluoroscopy: physician's hand dose and development of needle holders.

    PubMed

    Kato, R; Katada, K; Anno, H; Suzuki, S; Ida, Y; Koga, S

    1996-11-01

    The radiation dose to physicians' hands without and with use of needle holders was determined at 10 computed tomography (CT) fluoroscopy-guided transthoracic needle biopsies. As measured with ionization chambers (tube voltage, 80 kVp; tube current, 30 mA), the mean absorbed dose rate without and with holders was 1.14 mGy/sec +/- 0.02 (standard deviation) and 0.019 mGy/sec +/- 0.001, respectively. The mean duration of CT fluoroscopy was 59 seconds in 10 biopsies performed with a holder and 82 seconds in 10 biopsies performed without a holder (difference not statistically significant). The needle holders did not cause any artifacts that interfered with the biopsy procedure.

  11. Radiation dosimetry of iodine-123 HEAT, an alpha-1 receptor imaging agent

    SciTech Connect

    Thomas, K.D.; Greer, D.M.; Couch, M.W.; Williams, C.M.

    1987-11-01

    Biologic distribution data in the rat were obtained for the alpha-1 adrenoceptor imaging agent (+/-) 2-(beta-(iodo-4-hydroxyphenyl)ethylaminomethyl)tetralone (HEAT) labeled with (/sup 123/I). The major excretory routes were through the liver (67%) and the kidney (33%). Internal radiation absorbed dose estimates to nine source organs, total body, the GI tract, gonads, and red bone marrow were calculated for the human using the physical decay data for (/sup 123/I). The critical organ was found to be the lower large intestine, receiving 1.1 rad per mCi of (/sup 123/I)HEAT administered. The total-body dose was found to be 58 mrad per mCi.

  12. Preparation of CaSO4:Dy by precipitation method to gamma radiation dosimetry.

    PubMed

    Rivera, T; Roman, J; Azorín, J; Sosa, R; Guzmán, J; Serrano, A K; García, M; Alarcón, G

    2010-01-01

    This paper presents the results of the preparation and characterization of dysprosium-doped calcium sulfate (CaSO(4):Dy) phosphor, which was obtained by homogeneous precipitation from calcium acetate Ca(CH(3)COO(-))(2). Structural and morphological characteristics were studied using a scanning electronic microscope (SEM). The structure of all compounds was determined by X-ray diffraction method too. Thermoluminescence (TL) emission properties of CaSO(4):Dy under gamma radiation effects were studied. This phosphor powder presented a TL glow curve with two peaks (Tmax) centered at around of 180 and 300 degrees C, respectively. The TL response of CaSO(4):Dy as a function of gamma absorbed dose was linear in a wide range. Both emission and excitation spectra were also obtained. Results showed that this new preparation method of CaSO(4):Dy TL phosphor is less expensive, cleaner and safer than the conventional preparation method.

  13. Assessment of occupational and patient dose from diagnostic and therapeutic radiation exposure using thermoluminescent dosimetry.

    PubMed

    Banu, H; Alam, M N; Chowdhury, M I; Kamal, M; Bardhan, D K; Chakraborty, D

    1998-04-01

    Radiation doses of occupational personnel exposed from diagnostic x rays, therapeutic installations, and patients were measured using thermoluminescent dosimeters. The monthly occupational doses from diagnostic x ray ranged from 0.1076 mSv to 0.5774 mSv, and those from therapeutic treatment ranged from 0.365 mSv to 0.657 mSv, which is within the dose limit recommended by ICRP 60. The patient organ doses were evaluated and found to range from 0.0615 mSv s(-1) to 2.8823 mSv s(-1) for gonad, 0.3676 mSv s(-1) to 2.1088 mSv s(-1) for thyroid, and 0.00972 mSv s(-1) to 4.01 mSv s(-1) for eyes. PMID:9525423

  14. Synthesis and radiation dosimetry of 4-borono-2-[18F]fluoro-D,L-phenylalanine: a target compound for PET and boron neutron capture therapy.

    PubMed

    Ishiwata, K; Ido, T; Mejia, A A; Ichihashi, M; Mishima, Y

    1991-01-01

    The 18F-labeling of 4-borono-D-L-phenylalanine (BPA), a potential target compound for cancer treatment with boron neutron capture therapy, is described. By direct fluorination of BPA with [18F]AcOF or [18F]F2 followed by HPLC separation, 4-borono-2-[18F]fluoro-D,L-phenylalanine was prepared with radiochemical yields of 25-35% and with a radiochemical purity of over 99%. The tissue distribution study showed that the compound has potential as a tracer for pancreas imaging with positron emission tomography. Radiation dosimetry is also described.

  15. SU-C-BRE-04: Microbeam-Radiation-Therapy (MRT): Characterizing a Novel MRT Device Using High Resolution 3D Dosimetry

    SciTech Connect

    Li, Q; Juang, T; Bache, S; Chang, S; Oldham, M

    2014-06-15

    Purpose: The feasibility of MRT has recently been demonstrated utilizing a new technology of Carbon-Nano-Tube(CNT) field emission x-ray sources.This approach can deliver very high dose(10's of Gy) in narrow stripes(sub-mm) of radiation which enables the study of novel radiation treatment approaches. Here we investigate the application of highresolution (50um isotropic) PRESAGE/Optical-CT 3D dosimetry techniques to characterize the radiation delivered in this extremely dosimetrically challenging scenario. Methods: The CNT field emission x-ray source irradiator comprises of a linear cathode array and a novel collimator alignment system. This allows a precise delivery of high-energy small beams up to 160 kVp. A cylindrical dosimeter (∼2.2cm in height ∼2.5cm in diameter) was irradiated by CNT MRT delivering 3 strips of radiation with a nominal entrance dose of 32 Gy.A second dosimeter was irradiated with similar entrance dose, with a regular x-ray irradiator collimated to microscopical strip-beams. 50um (isotropic) 3D dosimetry was performed using an in-house optical-CT system designed and optimized for high resolution imaging (including a stray light deconvolution correction).The percentage depth dose (PDD), peak-to-valley ratio (PVR) and beam width (FWHM) data were obtained and analyzed in both cases. Results: High resolution 3D images were successfully achieved with the prototype system, enabling extraction of PDD and dose profiles. The PDDs for the CNT irradiation showed pronounced attenuation, but less build-up effect than that from the multibeam irradiation. The beam spacing between the three strips has an average value of 0.9mm while that for the 13 strips is 1.5 mm at a depth of 16.5 mm. The stray light corrected image shows line profiles with reduced noise and consistent PVR values. Conclusion: MRT dosimetry is extremely challenging due to the ultra small fields involved.This preliminary application of a novel, ultra-high resolution, optical-CT 3D

  16. Review of Cytogenetic analysis of restoration workers for Fukushima Daiichi nuclear power station accident.

    PubMed

    Suto, Yumiko

    2016-09-01

    Japan faced with the nuclear accident of the Fukushima Daiichi Nuclear Power Station (NPS) caused by the combined disaster of the Great East Japan Earthquake and the subsequent tsunamis on 11 March 2011. National Institute of Radiological Sciences received all nuclear workers who were engaged in emergency response tasks at the NPS and suspected of being overexposed to acute radiation. Biological dosimetry by dicentric chromosome assay was helpful for medical triage and management of the workers. PMID:27473701

  17. Review of Cytogenetic analysis of restoration workers for Fukushima Daiichi nuclear power station accident.

    PubMed

    Suto, Yumiko

    2016-09-01

    Japan faced with the nuclear accident of the Fukushima Daiichi Nuclear Power Station (NPS) caused by the combined disaster of the Great East Japan Earthquake and the subsequent tsunamis on 11 March 2011. National Institute of Radiological Sciences received all nuclear workers who were engaged in emergency response tasks at the NPS and suspected of being overexposed to acute radiation. Biological dosimetry by dicentric chromosome assay was helpful for medical triage and management of the workers.

  18. Three dimensional radiation dosimetry in lung-equivalent regions by use of a radiation sensitive gel foam: Proof of principle

    SciTech Connect

    Deene, Yves de; Vergote, Koen; Claeys, Carolien; De Wagter, Carlos

    2006-07-15

    A polymer hydrogel foam is proposed as a potential three dimensional experimental dosimeter for radiation treatment verification in low-density tissue such as the lung. A gel foam is created by beating a radiation sensitive polymer gel mixture in an anoxic atmosphere. The mass density of the gel foam is in the order of 0.25-0.35 kg/dm{sup 3}. Both nuclear magnetic resonance (NMR) spin-spin relaxation rate (R2) and magnetization transfer ratio (MTR) have been used to map the dose distribution from the gel dosimeter. It is found that MTR has significant advantages compared to R2 for mapping the dose distribution in the polymer gel foam dosimeters. The magnetization transfer ratio is found to be less dependent on the density and microstructure of the gel foam dosimeter while spin-spin relaxation dispersion has been observed making the spin-spin relaxation rate dependent on the interecho time interval. Optical microscopy reveals a microstructure that shows great similarity with human lung tissue. It is also shown how NMR hydrogen proton density measurements can be used to map the density distributions in gel dosimeters.

  19. Advances in a framework to compare bio-dosimetry methods for triage in large-scale radiation events

    PubMed Central

    Flood, Ann Barry; Boyle, Holly K.; Du, Gaixin; Demidenko, Eugene; Nicolalde, Roberto J.; Williams, Benjamin B.; Swartz, Harold M.

    2014-01-01

    Planning and preparation for a large-scale nuclear event would be advanced by assessing the applicability of potentially available bio-dosimetry methods. Using an updated comparative framework the performance of six bio-dosimetry methods was compared for five different population sizes (100–1 000 000) and two rates for initiating processing of the marker (15 or 15 000 people per hour) with four additional time windows. These updated factors are extrinsic to the bio-dosimetry methods themselves but have direct effects on each method's ability to begin processing individuals and the size of the population that can be accommodated. The results indicate that increased population size, along with severely compromised infrastructure, increases the time needed to triage, which decreases the usefulness of many time intensive dosimetry methods. This framework and model for evaluating bio-dosimetry provides important information for policy-makers and response planners to facilitate evaluation of each method and should advance coordination of these methods into effective triage plans. PMID:24729594

  20. Effect of Cerebellum Radiation Dosimetry on Cognitive Outcomes in Children With Infratentorial Ependymoma

    SciTech Connect

    Merchant, Thomas E.; Sharma, Shelly; Xiong, Xiaoping; Wu, Shengjie; Conklin, Heather

    2014-11-01

    Purpose: Cognitive decline is a recognized effect of radiation therapy (RT) in children treated for brain tumors. The importance of the cerebellum and its contribution to cognition have been recognized; however, the effect of RT on cerebellum-linked neurocognitive deficits has yet to be explored. Methods and Materials: Seventy-six children (39 males) at a median 3.3 years of age (range, 1-17 years old) were irradiated for infratentorial ependymoma from 1997 to 2008. The total prescribed dose was 54 to 59.4 Gy administered to the postoperative tumor bed with 5- or 10-mm clinical target volume margin. Age-appropriate cognitive and academic testing was performed prior to the start of RT and was then repeated at 6 months and annually throughout 5 years. The anterior and posterior cerebellum and other normal brain volumes were contoured on postcontrast, T1-weighted postoperative magnetic resonance images registered to treatment planning computed tomography images. Mean doses were calculated and used with time after RT and other clinical covariates to model their effect on neurocognitive test scores. Results: Considering only the statistically significant rates in longitudinal changes for test scores and models that included mean dose, there was a correlation between mean infratentorial dose and intelligence quotient (IQ; −0.190 patients/Gy/year; P=.001), math (−0.164 patients/Gy/year; P=.010), reading (−0.137 patients/Gy/year; P=.011), and spelling scores (−0.147 patients/Gy/year; P=.012), where Gy was measured as the difference between the mean dose received by an individual patient and the mean dose received by the patient group. There was a correlation between mean anterior cerebellum dose and IQ scores (−0.116 patients/Gy/year; P=.042) and mean posterior cerebellum dose and IQ (−0.150 patients/Gy/year; P=.002), math (−0.120 patients/Gy/year; P=.023), reading (−0.111 patients/Gy/year; P=.012), and spelling (−0.117 patients/Gy/year; P=.015

  1. Human radiation dosimetry of 6-[{sup 18}F]FDG predicted from preclinical studies

    SciTech Connect

    Muzic, Raymond F.; Chandramouli, Visvanathan; Hatami, Ahmad; Huang, Hsuan-Ming; Wu, Chunying; Ismail-Beigi, Faramarz

    2014-03-15

    Purpose: The authors are developing 6-[{sup 18}F]fluoro-6-deoxy-D-glucose (6-[{sup 18}F]FDG) as an in vivo tracer of glucose transport. While 6-[{sup 18}F]FDG has the same radionuclide half-life as 2-[{sup 18}F]fluoro-2-deoxy-D-glucose (2-[{sup 18}F]FDG) which is ubiquitously used for PET imaging, 6-[{sup 18}F]FDG has special biologic properties and different biodistributions that make it preferable to 2-[{sup 18}F]FDG for assessing glucose transport. In preparation for 6-[{sup 18}F]FDG use in human PET scanning, the authors would like to determine the amount of 6-[{sup 18}F]FDG to inject while maintaining radiation doses in a safe range. Methods: Rats were injected with 6-[{sup 18}F]FDG, euthanized at specified times, and tissues were collected and assayed for activity content. For each tissue sample, the percent of injected dose per gram was calculated and extrapolated to that for humans in order to construct predicted time-courses. Residence times were calculated as areas under the curves and were used as inputs to OLINDA/EXM in order to calculate the radiation doses. Results: Unlike with 2-[{sup 18}F]FDG for which the urinary bladder wall receives the highest absorbed dose due to urinary excretion, with 6-[{sup 18}F]FDG there is little urinary excretion and osteogenic cells and the liver are predicted to receive the highest absorbed doses: 0.027 mGy/MBq (0.100 rad/mCi) and 0.018 mGy/MBq (0.066 rad/mCi), respectively. Also, the effective dose from 6-[{sup 18}F]FDG, i.e., 0.013 mSv/MBq (0.046 rem/mCi), is predicted to be approximately 30% lower than that from 2-[{sup 18}F]FDG. Conclusions: 6-[{sup 18}F]FDG will be safe for use in the PET scanning of humans.

  2. Bone structural parameters, dosimetry, and relative radiation risk in the beagle skeleton

    SciTech Connect

    Polig, E.; Jee, W.S. )

    1989-10-01

    A variety of morphometric and histomorphometric parameters such as the mass of bone and marrow, bone surface areas, percentage of bone volume, percentage of the surface that is trabecular, and percentage of surfaces that are forming and resting are calculated for all major parts of the beagle skeleton. The total bone surface of the beagle is estimated at 2.9 m2 with 53.7% of the surface area being associated with trabecular bone. There are about 4.5 x 10(9) bone-lining cells and about 1 x 10(9) osteoblasts. From the fractional retention in each part of the skeleton, the initial surface concentration of 239Pu after a single injection of 592 Bq/kg body wt (0.016 microCi/kg) on resting surfaces and at sites of bone formation is calculated for various values of the affinity ratios of trabecular/cortical and forming/resting surfaces. These estimated concentrations then yield dose rates as well as cumulative and collective doses to bone-lining cells and osteoblasts in the different parts of the skeleton. On the assumption that the relative risk of tumor induction is proportional to the collective dose to either bone-lining cells or osteoblasts, the frequency of tumor occurrence is calculated and compared to observed frequencies. Both hypotheses yield approximate agreement with experimental data for different ratios of trabecular/cortical radiation sensitivity, although the differences between some bones are statistically significant.

  3. Biologically effective dose of solar ultraviolet radiation estimated by spore dosimetry in Tokyo since 1980.

    PubMed

    Munakata, N

    1993-09-01

    The biologically effective dose of solar UV radiation has been measured in Tokyo since 1980 using Bacillus subtilis spores. To determine the cumulative dose in a half day, several samples of UV-sensitive spores were exposed in successive intervals from the solar-noon time. Because fluence-survival curves were exponential, the number of lethal hits received by the spores was calculated for each interval and termed inactivation dose (ID). The total number of hits obtained in a half day (half-day ID) was correlated with the amount of global insolation by a power-function regression. The regression analyses were performed for the data collected on 35 days from 1980 to 1986 and for the data collected on 53 days from 1989 to 1991. The latter data set yielded significantly larger estimates of half-day ID relative to the insolation than the former. These analyses suggested that the biologically effective dose relative to the insolation increased about 30% at some time in the later part of 1980s at this location. Changes of solar activity, air pollution and stratospheric ozone layer were considered as potentially responsible for this increase, but identification of the causative factors requires further efforts.

  4. A CUDA Monte Carlo simulator for radiation therapy dosimetry based on Geant4

    NASA Astrophysics Data System (ADS)

    Henderson, N.; Murakami, K.; Amako, K.; Asai, M.; Aso, T.; Dotti, A.; Kimura, A.; Gerritsen, M.; Kurashige, H.; Perl, J.; Sasaki, T.

    2014-06-01

    Geant4 is a large-scale particle physics package that facilitates every aspect of particle transport simulation. This includes, but is not limited to, geometry description, material definition, tracking of particles passing through and interacting with matter, storage of event data, and visualization. As more detailed and complex simulations are required in different application domains, there is much interest in adapting the code for parallel and multi-core architectures. Parallelism can be achieved by tracking many particles at the same time. The complexity in the context of a GPU/CUDA adaptation is the highly serialized nature of the Geant4 package and the presence of large lookup tables that guide the simulation. This work presents G4CU, a CUDA implementation of the core Geant4 algorithm adapted for dose calculations in radiation therapy. For these applications the geometry is a block of voxels and the physics is limited to low energy electromagnetic physics. These features allow efficient tracking of many particles in parallel on the GPU. Experiments with radiotherapy simulations in G4CU demonstrate about 40 times speedups over Geant4.

  5. Track-etched detectors for the dosimetry of the radiation of cosmic origin.

    PubMed

    Spurný, F; Turek, K

    2004-01-01

    Cosmic rays contribute to the exposure on the Earth's surface as well as in its surroundings. At the surface and/or at aviation altitudes, there are mostly secondary particles created through the cosmic rays interaction in the atmosphere, which contribute to this type of exposure. Onboard a spacecraft, the exposure comes mostly from primary cosmic rays. Track-etched detectors (TED) are able to characterise both these types of exposure. The contribution of neutrons, of cosmic origin, on the Earth's surface was studied at altitudes from few hundreds to 3000 m using TED in a moderator sphere. The results obtained are compared with other data on this type of natural radiation background. The results of studies performed onboard aircraft and/or spacecraft are presented afterwards. We used TED-based neutron dosemeter, as well as a spectrometer of linear energy transfer based on a chemically etched TED. The results of studies performed onboard aircraft, as well as spacecraft, are presented and discussed, including an attempt to estimate a neutron component onboard the spacecraft. It was found that they correlate with the results of other independent investigations.

  6. Radiation dosimetry measurements with real time radiation monitoring device (RRMD)-II in Space Shuttle STS-79.

    PubMed

    Sakaguchi, T; Doke, T; Hayashi, T; Kikuchi, J; Hasebe, N; Kashiwagi, T; Takashima, T; Takahashi, K; Nakano, T; Nagaoka, S; Takahashi, S; Yamanaka, H; Yamaguchi, K; Badhwar, G D

    1997-12-01

    The real-time measurement of radiation environment was made with an improved real-time radiation monitoring device (RRMD)-II onboard Space Shuttle STS-79 (S/MM#4: 4th Shuttle MIR Mission, at an inclination angle of 51.6 degrees and an altitude of 250-400km) for 199 h during 17-25 September, 1996. The observation of the detector covered the linear energy transfer (LET) range of 3.5-6000 keV/micrometer. The Shuttle orbital profile in this mission was equivalent to that of the currently planned Space Station, and provided an opportunity to investigate variations in count rate and dose equivalent rate depending on altitude, longitude, and latitude in detail. Particle count rate and dose equivalent rate were mapped geographically during the mission. Based on the map of count rate, an analysis was made by dividing whole region into three regions: South Atlantic Anomaly (SAA) region, high latitude region and other regions. The averaged absorbed dose rate during the mission was 39.3 microGy/day for a LET range of 3.5-6000 keV/micrometer. The corresponding average dose equivalent rates during the mission are estimated to be 293 microSv/day with quality factors from International Commission on Radiological Protection (ICRP)-Pub. 60 and 270 microSv/day with quality factors from ICRP-Pub. 26. The effective quality factors for ICRP-Pub. 60 and 26 are 7.45 and 6.88, respectively. From the present data for particles of LET > 3.5keV/micrometer, we conclude that the average dose equivalent rate is dominated by the contribution of galactic cosmic ray (GCR) particles. The dose-detector depth dependence was also investigated.

  7. Occupational hazards in hospitals: accidents, radiation, exposure to noxious chemicals, drug addiction and psychic problems, and assault.

    PubMed Central

    Gestal, J J

    1987-01-01

    Except for infectious diseases all the main occupational hazards affecting health workers are reviewed: accidents (explosions, fires, electrical accidents, and other sources of injury); radiation (stochastic and non-stochastic effects, protective measures, and personnel most at risk); exposure to noxious chemicals, whose effects may be either local (allergic eczema) or generalised (cancer, mutations), particular attention being paid to the hazards presented by formol, ethylene oxide, cytostatics, and anaesthetic gases; drug addiction (which is more common among health workers than the general population) and psychic problems associated with promotion, shift work, and emotional stress; and assault (various types of assault suffered by health workers, its causes, and the characterisation of the most aggressive patients). PMID:3307896

  8. Application of real-time radiation dosimetry using a new silicon LET sensor

    NASA Technical Reports Server (NTRS)

    Doke, T.; Hayashi, T.; Kikuchi, J.; Nagaoka, S.; Nakano, T.; Sakaguchi, T.; Terasawa, K.; Badhwar, G. D.

    1999-01-01

    A new type of real-time radiation monitoring device, RRMD-III, consisting of three double-sided silicon strip detectors (DSSDs), has been developed and tested on-board the Space Shuttle mission STS-84. The test succeeded in measuring the linear energy transfer (LET) distribution over the range of 0.2 keV/micrometer to 600 keV/micrometer for 178 h. The Shuttle cruised at an altitude of 300 to 400 km and an inclination angle of 51.6 degrees for 221.3 h, which is equivalent to the International Space Station orbit. The LET distribution obtained for particles was investigated by separating it into galactic cosmic ray (GCR) particles and trapped particles in the South Atlantic Anomaly (SAA) region. The result shows that the contribution in dose-equivalent due to GCR particles is almost equal to that from trapped particles. The total absorbed dose rate during the mission was 0.611 mGy/day; the effective quality factor, 1.64; and the dose equivalent rate, 0.998 mSv/day. The average absorbed dose rates are 0.158 mGy/min for GCR particles and 3.67 mGy/min for trapped particles. The effective quality factors are 2.48 for GCR particles and 1.19 for trapped particles. The absorbed doses obtained by the RRMD-III and a conventional method using TLD (Mg(2)SiO(4)), which was placed around the RRMD-III were compared. It was found that the TLDs showed a lower efficiency, just 58% of absorbed dose registered by the RRMD-III.

  9. A revised model for radiation dosimetry in the human gastrointestinal tract

    NASA Astrophysics Data System (ADS)

    Bhuiyan, Md. Nasir Uddin

    showed that the "self-dose" for the energies below 300 keV and the "cross-dose" below 2 MeV were only from bremsstrahlung and fluorescent radiations at the depth of the stem cells and were not important.

  10. Primary mandibular reconstruction: analysis of 64 cases and evaluation of interface radiation dosimetry on bridging plates

    SciTech Connect

    Gullane, P.J. )

    1991-06-01

    The combination of a myocutaneous flap or free cutaneous tissue transfer with a three-dimensional bendable reconstruction plate either of stainless steel or titanium has provided very satisfactory results in primary restoration of mandibular defects following surgical resections in irradiated patients or in those who require postoperative radiotherapy. Sixty-four cases have been treated and evaluated prospectively using this technique. Fifty-three of the patients had the soft-tissue defect restored with a myocutaneous flap, 8 had a free cutaneous tissue flap, 2 were reconstructed with tongue flaps, and 1 closed primarily. The stainless steel plate of the A.O. type was used in 53 cases and the titanium plate system and hollow screws in the other 11 cases. A success rate of 78.9% was found with a median follow-up of 384 days. Thirty of the 64 cases had preoperative irradiation and 15 were treated postoperatively. A plate failure rate of 23% was encountered in those treated with preoperative irradiation and in 20% with those having postoperative irradiation. Forty-nine of the 64 patients or 76.5% experienced no perioperative complications. Five or 7.8% of the complications were minor. Ten patients or 15.6% experienced a major complication with one death due to a myocardial infarct. A radiation dosimetric model was employed using both stainless steel and titanium. The results from this study showed that, when using a parallel pair of beams, an excess dose of irradiation for the lowest energy cobalt-60 is 13%, for 6 mV it is 15%, and for 18 mV it is 20%. The excess tissue dose, both for stainless steel and titanium plates, extends for about 0.2 mm for cobalt-60, 1.1 mm at 6 mV, and for 25 mm at 18 mV. Patients with plates, therefore, can be treated safely with postoperative irradiation using either cobalt-60 or 6-mV energy.

  11. Internal dosimetry technical basis manual

    SciTech Connect

    Not Available

    1990-12-20

    The internal dosimetry program at the Savannah River Site (SRS) consists of radiation protection programs and activities used to detect and evaluate intakes of radioactive material by radiation workers. Examples of such programs are: air monitoring; surface contamination monitoring; personal contamination surveys; radiobioassay; and dose assessment. The objectives of the internal dosimetry program are to demonstrate that the workplace is under control and that workers are not being exposed to radioactive material, and to detect and assess inadvertent intakes in the workplace. The Savannah River Site Internal Dosimetry Technical Basis Manual (TBM) is intended to provide a technical and philosophical discussion of the radiobioassay and dose assessment aspects of the internal dosimetry program. Detailed information on air, surface, and personal contamination surveillance programs is not given in this manual except for how these programs interface with routine and special bioassay programs.

  12. Dose levels of the occupational radiation exposures in Poland based on results from the accredited dosimetry service at the IFJ PAN, Krakow.

    PubMed

    Budzanowski, Maciej; Kopeć, Renata; Obryk, Barbara; Olko, Paweł

    2011-03-01

    Individual dosimetry service based on thermoluminescence (TLD) detectors has started its activity at the Institute of Nuclear Physics (IFJ) in Krakow in 1965. In 2002, the new Laboratory of Individual and Environment Dosimetry (Polish acronym LADIS) was established and underwent the accreditation according to the EN-PN-ISO/IEC 17025 standard. Nowadays, the service is based on the worldwide known standard thermoluminescent detectors MTS-N (LiF:Mg,Ti) and MCP-N (LiF:Mg,Cu,P), developed at IFJ, processed in automatic thermoluminescent DOSACUS or RE2000 (Rados Oy, Finland) readers. Laboratory provides individual monitoring in terms of personal dose equivalent H(p)(10) and H(p)(0.07) in photon and neutron fields, over the range from 0.1 mSv to 1 Sv, and environmental dosimetry in terms of air kerma K(a) over the range from 30 μGy to 1 Gy and also ambient dose equivalent H*(10) over the range from 30 μSv to 1 Sv. Dosimetric service is currently performed for ca. 3200 institutions from Poland and abroad, monitored on quarterly and monthly basis. The goal of this paper is to identify the main activities leading to the highest radiation exposures in Poland. The paper presents the results of statistical evaluation of ∼ 100,000 quarterly H(p)(10) and K(a) measurements performed between 2002 and 2009. Sixty-five per cent up to 90 % of all individual doses in Poland are on the level of natural radiation background. The dose levels between 0.1 and 5 mSv per quarter are the most frequent in nuclear medicine, veterinary and industrial radiography sectors. PMID:21183549

  13. Radiation Dosimetry Experiment (RaD-X): High-Altitude Balloon Flight Mission for Improving the Nairas Aviation Radiation Model

    NASA Astrophysics Data System (ADS)

    Mays, M. L.; Luhmann, J. G.; Odstrcil, D.; Schwadron, N.; Gorby, M.; Bain, H. M.; Mewaldt, R. A.; Gold, R. E.

    2014-12-01

    In preparation for Solar Probe Plus and Solar Orbiter we consider a series of SEP modeling experiments based on the global MHD WSA-ENLIL model. The models include the Solar Energetic Particle Model (SEPMOD) (Luhmann et al., 2007; 2010) and the Earth-Moon-Mars Radiation Environment Module (EMMREM) (Schwadron et al., 2010)). WSA-ENLIL provides a time-dependent background heliospheric description including CME-like clouds which can generate shocks during their propagation. SEPMOD makes use of the ENLIL-provided magnetic topologies of observer-connected magnetic field lines and all plasma and shock properties along those field lines. The model injects protons onto a sequence observer field lines at intensities dependent on the connected shock source strength which are then integrated at the observer to approximate the proton flux. EMMREM couples with MHD models such as ENLIL and computes energetic particle distributions based on the focused transport equation along a Lagrangian grid of nodes that propagate out with the solar wind. In this presentation we compare SEP modeling results with data, and consider SEP variability in longitude and latitude. Additionally we study the relative importance of observer-connectivity to the solar source and shock locations, as derived from ENLIL. We evaluate the shock geometry and compare model-derived shock parameters with those observed. Finally, we test the effect of the seed population on the resulting profiles.

  14. Retrospective dosimetry using EPR and TL techniques: a status report

    SciTech Connect

    Haskell, E.H.

    1996-12-31

    Methods of retrospective dosimetry, including luminescence and electron paramagnetic resonance spectroscopy (EPR), rely on measurement of accident dose absorbed by naturally occurring materials - ceramics in the case of both thermoluminescence (TL) and optically stimulated luminescence (OSL) and organic materials and bio- minerals in the case of EPR. Each of these methods relies on measurement of radiation defects resulting from accidental exposure. Since defects also result from natural sources of radiation over the lifetime of a sample, analysis is usually restricted to materials for which the natural dose may be determined and subtracted from the measured cumulative dose. Luminescence dating techniques rely heavily on an accurate assessment of cumulative dose from natural radiation sources, and dating research has provided us with the bulk of our knowledge in this area. Virtually all of the work on natural dose determination can be directly applied to retrospective techniques. With EPR techniques the cumulative dose from diagnostic x- rays is also of importance.

  15. Was the Risk from Nursing-Home Evacuation after the Fukushima Accident Higher than the Radiation Risk?

    PubMed

    Murakami, Michio; Ono, Kyoko; Tsubokura, Masaharu; Nomura, Shuhei; Oikawa, Tomoyoshi; Oka, Tosihiro; Kami, Masahiro; Oki, Taikan

    2015-01-01

    After the 2011 accident at the Fukushima Daiichi nuclear power plant, nursing-home residents and staff were evacuated voluntarily from damaged areas to avoid radiation exposure. Unfortunately, the evacuation resulted in increased mortalities among nursing home residents. We assessed the risk trade-off between evacuation and radiation for 191 residents and 184 staff at three nursing homes by using the same detriment indicator, namely loss of life expectancy (LLE), under four scenarios, i.e. "rapid evacuation (in accordance with the actual situation; i.e. evacuation on 22 March)," "deliberate evacuation (i.e. evacuation on 20 June)," "20-mSv exposure," and "100-mSv exposure." The LLE from evacuation-related mortality among nursing home residents was assessed with survival probability data from nursing homes in the city of Minamisoma and the city of Soma. The LLE from radiation mortality was calculated from the estimated age-specific mortality rates from leukemia and all solid cancers based on the additional effective doses and the survival probabilities. The total LLE of residents due to evacuation-related risks in rapid evacuation was 11,000 persons-d-much higher than the total LLEs of residents and staff due to radiation in the other scenarios (27, 1100, and 5800 persons-d for deliberate evacuation, 20 mSv-exposure, and 100 mSv-exposure, respectively). The latitude for reducing evacuation risks among nursing home residents is surprisingly large. Evacuation regulation and planning should therefore be well balanced with the trade-offs against radiation risks. This is the first quantitative assessment of the risk trade-off between radiation exposure and evacuation after a nuclear power plant accident.

  16. Was the Risk from Nursing-Home Evacuation after the Fukushima Accident Higher than the Radiation Risk?

    PubMed

    Murakami, Michio; Ono, Kyoko; Tsubokura, Masaharu; Nomura, Shuhei; Oikawa, Tomoyoshi; Oka, Tosihiro; Kami, Masahiro; Oki, Taikan

    2015-01-01

    After the 2011 accident at the Fukushima Daiichi nuclear power plant, nursing-home residents and staff were evacuated voluntarily from damaged areas to avoid radiation exposure. Unfortunately, the evacuation resulted in increased mortalities among nursing home residents. We assessed the risk trade-off between evacuation and radiation for 191 residents and 184 staff at three nursing homes by using the same detriment indicator, namely loss of life expectancy (LLE), under four scenarios, i.e. "rapid evacuation (in accordance with the actual situation; i.e. evacuation on 22 March)," "deliberate evacuation (i.e. evacuation on 20 June)," "20-mSv exposure," and "100-mSv exposure." The LLE from evacuation-related mortality among nursing home residents was assessed with survival probability data from nursing homes in the city of Minamisoma and the city of Soma. The LLE from radiation mortality was calculated from the estimated age-specific mortality rates from leukemia and all solid cancers based on the additional effective doses and the survival probabilities. The total LLE of residents due to evacuation-related risks in rapid evacuation was 11,000 persons-d-much higher than the total LLEs of residents and staff due to radiation in the other scenarios (27, 1100, and 5800 persons-d for deliberate evacuation, 20 mSv-exposure, and 100 mSv-exposure, respectively). The latitude for reducing evacuation risks among nursing home residents is surprisingly large. Evacuation regulation and planning should therefore be well balanced with the trade-offs against radiation risks. This is the first quantitative assessment of the risk trade-off between radiation exposure and evacuation after a nuclear power plant accident. PMID:26359666

  17. Was the Risk from Nursing-Home Evacuation after the Fukushima Accident Higher than the Radiation Risk?

    PubMed Central

    Murakami, Michio; Ono, Kyoko; Tsubokura, Masaharu; Nomura, Shuhei; Oikawa, Tomoyoshi; Oka, Tosihiro; Kami, Masahiro; Oki, Taikan

    2015-01-01

    After the 2011 accident at the Fukushima Daiichi nuclear power plant, nursing-home residents and staff were evacuated voluntarily from damaged areas to avoid radiation exposure. Unfortunately, the evacuation resulted in increased mortalities among nursing home residents. We assessed the risk trade-off between evacuation and radiation for 191 residents and 184 staff at three nursing homes by using the same detriment indicator, namely loss of life expectancy (LLE), under four scenarios, i.e. “rapid evacuation (in accordance with the actual situation; i.e. evacuation on 22 March),” “deliberate evacuation (i.e. evacuation on 20 June),” “20-mSv exposure,” and “100-mSv exposure.” The LLE from evacuation-related mortality among nursing home residents was assessed with survival probability data from nursing homes in the city of Minamisoma and the city of Soma. The LLE from radiation mortality was calculated from the estimated age-specific mortality rates from leukemia and all solid cancers based on the additional effective doses and the survival probabilities. The total LLE of residents due to evacuation-related risks in rapid evacuation was 11,000 persons-d—much higher than the total LLEs of residents and staff due to radiation in the other scenarios (27, 1100, and 5800 persons-d for deliberate evacuation, 20 mSv-exposure, and 100 mSv-exposure, respectively). The latitude for reducing evacuation risks among nursing home residents is surprisingly large. Evacuation regulation and planning should therefore be well balanced with the trade-offs against radiation risks. This is the first quantitative assessment of the risk trade-off between radiation exposure and evacuation after a nuclear power plant accident. PMID:26359666

  18. The International Reactor Dosimetry File.

    2008-08-07

    Version 01 The International Reactor Dosimetry File (IRDF-2002) contains recommended neutron cross-section data to be used for reactor neutron dosimetry by foil activation and subsequent neutron spectrum unfolding. It also contains selected recom�mended values for radiation damage cross-sections and benchmark neutron spectra. Two related programs available from NEADB and RSICC are: SPECTER-ANL (PSR-263) & STAY’SL (PSR-113).

  19. Internal radiation exposure dose in Iwaki city, Fukushima prefecture after the accident at Fukushima Dai-ichi Nuclear Power Plant.

    PubMed

    Orita, Makiko; Hayashida, Naomi; Nukui, Hiroshi; Fukuda, Naoko; Kudo, Takashi; Matsuda, Naoki; Fukushima, Yoshiko; Takamura, Noboru

    2014-01-01

    As a result of the accident at the Fukushima Daiichi Nuclear Power Plant (FNPP) on 11 March 2011, a huge amount of radionuclides, including radiocesium, was released and spread over a wide area of eastern Japan. Although three years have passed since the accident, residents around the FNPP are anxious about internal radiation exposure due to radiocesium. In this study, we screened internal radiation exposure doses in Iwaki city of Fukushima prefecture, using a whole-body counter. The first screening was conducted from October 2012 to February 2013, and the second screening was conducted from May to November 2013. Study participants were employees of ALPINE and their families who underwent examination. A total of 2,839 participants (1,366 men and 1,473 women, 1-86 years old) underwent the first screening, and 2,092 (1,022 men and 1,070 women, 1-86 years old) underwent the second screening. The results showed that 99% of subjects registered below 300 Bq per body in the first screening, and all subjects registered below 300 Bq per body in the second screening. The committed effective dose ranged from 0.01-0.06 mSv in the first screening and 0.01-0.02 mSv in the second screening. Long-term follow-up studies are needed to avoid unnecessary chronic internal exposure and to reduce anxiety among the residents by communicating radiation health risks.

  20. Internal Radiation Exposure Dose in Iwaki City, Fukushima Prefecture after the Accident at Fukushima Dai-ichi Nuclear Power Plant

    PubMed Central

    Orita, Makiko; Hayashida, Naomi; Nukui, Hiroshi; Fukuda, Naoko; Kudo, Takashi; Matsuda, Naoki; Fukushima, Yoshiko; Takamura, Noboru

    2014-01-01

    As a result of the accident at the Fukushima Daiichi Nuclear Power Plant (FNPP) on 11 March 2011, a huge amount of radionuclides, including radiocesium, was released and spread over a wide area of eastern Japan. Although three years have passed since the accident, residents around the FNPP are anxious about internal radiation exposure due to radiocesium. In this study, we screened internal radiation exposure doses in Iwaki city of Fukushima prefecture, using a whole-body counter. The first screening was conducted from October 2012 to February 2013, and the second screening was conducted from May to November 2013. Study participants were employees of ALPINE and their families who underwent examination. A total of 2,839 participants (1,366 men and 1,473 women, 1–86 years old) underwent the first screening, and 2,092 (1,022 men and 1,070 women, 1–86 years old) underwent the second screening. The results showed that 99% of subjects registered below 300 Bq per body in the first screening, and all subjects registered below 300 Bq per body in the second screening. The committed effective dose ranged from 0.01–0.06 mSv in the first screening and 0.01–0.02 mSv in the second screening. Long-term follow-up studies are needed to avoid unnecessary chronic internal exposure and to reduce anxiety among the residents by communicating radiation health risks. PMID:25478794

  1. Internal radiation exposure dose in Iwaki city, Fukushima prefecture after the accident at Fukushima Dai-ichi Nuclear Power Plant.

    PubMed

    Orita, Makiko; Hayashida, Naomi; Nukui, Hiroshi; Fukuda, Naoko; Kudo, Takashi; Matsuda, Naoki; Fukushima, Yoshiko; Takamura, Noboru

    2014-01-01

    As a result of the accident at the Fukushima Daiichi Nuclear Power Plant (FNPP) on 11 March 2011, a huge amount of radionuclides, including radiocesium, was released and spread over a wide area of eastern Japan. Although three years have passed since the accident, residents around the FNPP are anxious about internal radiation exposure due to radiocesium. In this study, we screened internal radiation exposure doses in Iwaki city of Fukushima prefecture, using a whole-body counter. The first screening was conducted from October 2012 to February 2013, and the second screening was conducted from May to November 2013. Study participants were employees of ALPINE and their families who underwent examination. A total of 2,839 participants (1,366 men and 1,473 women, 1-86 years old) underwent the first screening, and 2,092 (1,022 men and 1,070 women, 1-86 years old) underwent the second screening. The results showed that 99% of subjects registered below 300 Bq per body in the first screening, and all subjects registered below 300 Bq per body in the second screening. The committed effective dose ranged from 0.01-0.06 mSv in the first screening and 0.01-0.02 mSv in the second screening. Long-term follow-up studies are needed to avoid unnecessary chronic internal exposure and to reduce anxiety among the residents by communicating radiation health risks. PMID:25478794

  2. Radiation-epidemiological Study of Cerebrovascular Diseases in the Cohort of Russian Recovery Operation Workers of the Chernobyl Accident.

    PubMed

    Kashcheev, V V; Chekin, S Yu; Maksioutov, M A; Tumanov, K A; Menyaylo, A N; Kochergina, E V; Kashcheeva, P V; Gorsky, A I; Shchukina, N V; Karpenko, S V; Ivanov, V K

    2016-08-01

    The paper presents an analysis of the incidence of cerebrovascular diseases (CeVD) in the cohort of Russian workers involved in recovery tasks after the Chernobyl accident. The studied cohort consists of 53,772 recovery operation workers (liquidators) who arrived in the zone of the Chernobyl accident within the first year after this accident (26 April 1986-26 April 1987). The mean external whole body dose in the cohort was 0.161 Gy, while individual doses varied from 0.0001 Gy to 1.42 Gy. During the follow-up period 1986-2012, a total of 23,264 cases of CeVD were diagnosed as a result of annual health examinations. A Poisson regression model was applied for estimation of radiation risks and for an assessment of other risk factors of CeVD. The following factors were considered as risk factors for CeVD: the dose, duration of the liquidators' work in the Chernobyl zone, and the concomitant diseases (hypertension, ischemic heart disease, atherosclerosis, and diabetes). The baseline incidence of CeVD is statistically significantly (p < 0.001) associated with all studied concomitant diseases. The incidence of CeVD has revealed a statistically significant dose response with the lack of a latent period and with the average ERR/Gy = 0.45, 95% CI: (0.28, 0.62), p < 0.001. Radiation risks of CeVD statistically significantly (p = 0.03) varied with the duration of liquidators' stay in the Chernobyl zone; for those who stayed in the Chernobyl zone less than 6 wk, ERR/Gy = 0.64, 95% CI = (0.38; 0.93), p < 0.001. Among studied concomitant diseases, diabetes mellitus statistically significantly (p = 0.002) increases the radiation risk of CeVD: for liquidators with diagnosed diabetes, ERR/Gy = 1.29. PMID:27356064

  3. Radiation-epidemiological Study of Cerebrovascular Diseases in the Cohort of Russian Recovery Operation Workers of the Chernobyl Accident.

    PubMed

    Kashcheev, V V; Chekin, S Yu; Maksioutov, M A; Tumanov, K A; Menyaylo, A N; Kochergina, E V; Kashcheeva, P V; Gorsky, A I; Shchukina, N V; Karpenko, S V; Ivanov, V K

    2016-08-01

    The paper presents an analysis of the incidence of cerebrovascular diseases (CeVD) in the cohort of Russian workers involved in recovery tasks after the Chernobyl accident. The studied cohort consists of 53,772 recovery operation workers (liquidators) who arrived in the zone of the Chernobyl accident within the first year after this accident (26 April 1986-26 April 1987). The mean external whole body dose in the cohort was 0.161 Gy, while individual doses varied from 0.0001 Gy to 1.42 Gy. During the follow-up period 1986-2012, a total of 23,264 cases of CeVD were diagnosed as a result of annual health examinations. A Poisson regression model was applied for estimation of radiation risks and for an assessment of other risk factors of CeVD. The following factors were considered as risk factors for CeVD: the dose, duration of the liquidators' work in the Chernobyl zone, and the concomitant diseases (hypertension, ischemic heart disease, atherosclerosis, and diabetes). The baseline incidence of CeVD is statistically significantly (p < 0.001) associated with all studied concomitant diseases. The incidence of CeVD has revealed a statistically significant dose response with the lack of a latent period and with the average ERR/Gy = 0.45, 95% CI: (0.28, 0.62), p < 0.001. Radiation risks of CeVD statistically significantly (p = 0.03) varied with the duration of liquidators' stay in the Chernobyl zone; for those who stayed in the Chernobyl zone less than 6 wk, ERR/Gy = 0.64, 95% CI = (0.38; 0.93), p < 0.001. Among studied concomitant diseases, diabetes mellitus statistically significantly (p = 0.002) increases the radiation risk of CeVD: for liquidators with diagnosed diabetes, ERR/Gy = 1.29.

  4. The Latin American Biological Dosimetry Network (LBDNet).

    PubMed

    García, O; Di Giorgio, M; Radl, A; Taja, M R; Sapienza, C E; Deminge, M M; Fernández Rearte, J; Stuck Oliveira, M; Valdivia, P; Lamadrid, A I; González, J E; Romero, I; Mandina, T; Guerrero-Carbajal, C; ArceoMaldonado, C; Cortina Ramírez, G E; Espinoza, M; Martínez-López, W; Di Tomasso, M

    2016-09-01

    Biological Dosimetry is a necessary support for national radiation protection programmes and emergency response schemes. The Latin American Biological Dosimetry Network (LBDNet) was formally founded in 2007 to provide early biological dosimetry assistance in case of radiation emergencies in the Latin American Region. Here are presented the main topics considered in the foundational document of the network, which comprise: mission, partners, concept of operation, including the mechanism to request support for biological dosimetry assistance in the region, and the network capabilities. The process for network activation and the role of the coordinating laboratory during biological dosimetry emergency response is also presented. This information is preceded by historical remarks on biological dosimetry cooperation in Latin America. A summary of the main experimental and practical results already obtained by the LBDNet is also included.

  5. Evaluation of the response to xenon-133 radiations by thermoluminescent dosimeters used during the accident at Three Mile Island.

    PubMed

    Riley, R J; Zanzonico, P B; Masterson, M E; St Germain, J M; Laughlin, J S

    1982-03-01

    An evaluation is presented of the accuracy and sensitivity of three types of TLD's used during the accident at the Three Mile Island Nuclear Station. This evaluation indicated that, due to the method of calibration, all the dosimeters over-responded to 133Xe radiations. The response ranged from slightly above unity to almost two. Exposures of the TLD's were of two types, namely, the characteristic X-rays either were or were not filtered from the beam. The angular sensitivity of the dosimeters is also reported. PMID:7068394

  6. A reference skeletal dosimetry model for an adult male radionuclide therapy patient based on three-dimensional imaging and paired-image radiation transport

    NASA Astrophysics Data System (ADS)

    Shah, Amish P.

    The need for improved patient-specificity of skeletal dose estimates is widely recognized in radionuclide therapy. Current clinical models for marrow dose are based on skeletal mass estimates from a variety of sources and linear chord-length distributions that do not account for particle escape into cortical bone. To predict marrow dose, these clinical models use a scheme that requires separate calculations of cumulated activity and radionuclide S values. Selection of an appropriate S value is generally limited to one of only three sources, all of which use as input the trabecular microstructure of an individual measured 25 years ago, and the tissue mass derived from different individuals measured 75 years ago. Our study proposed a new modeling approach to marrow dosimetry---the Paired Image Radiation Transport (PIRT) model---that properly accounts for both the trabecular microstructure and the cortical macrostructure of each skeletal site in a reference male radionuclide patient. The PIRT model, as applied within EGSnrc, requires two sets of input geometry: (1) an infinite voxel array of segmented microimages of the spongiosa acquired via microCT; and (2) a segmented ex-vivo CT image of the bone site macrostructure defining both the spongiosa (marrow, endosteum, and trabeculae) and the cortical bone cortex. Our study also proposed revising reference skeletal dosimetry models for the adult male cancer patient. Skeletal site-specific radionuclide S values were obtained for a 66-year-old male reference patient. The derivation for total skeletal S values were unique in that the necessary skeletal mass and electron dosimetry calculations were formulated from the same source bone site over the entire skeleton. We conclude that paired-image radiation-transport techniques provide an adoptable method by which the intricate, anisotropic trabecular microstructure of the skeletal site; and the physical size and shape of the bone can be handled together, for improved

  7. Calibration facility for environment dosimetry instruments

    SciTech Connect

    Bercea, Sorin; Celarel, Aurelia; Cenusa, Constantin

    2013-12-16

    In the last ten years, the nuclear activities, as well as the major nuclear events (see Fukushima accident) had an increasing impact on the environment, merely by contamination with radioactive materials. The most conferment way to quickly identify the presence of some radioactive elements in the environment, is to measure the dose-equivalent rate H. In this situation, information concerning the values of H due only to the natural radiation background must exist. Usually, the values of H due to the natural radiation background, are very low (∼10{sup −9} - 10{sup −8} Sv/h). A correct measurement of H in this range involve a performing calibration of the measuring instruments in the measuring range corresponding to the natural radiation background lead to important problems due to the presence of the natural background itself the best way to overlap this difficulty is to set up the calibration stand in an area with very low natural radiation background. In Romania, we identified an area with such special conditions at 200 m dept, in a salt mine. This paper deals with the necessary requirements for such a calibration facility, as well as with the calibration stand itself. The paper includes also, a description of the calibration stand (and images) as well as the radiological and metrological parameters. This calibration facilities for environment dosimetry is one of the few laboratories in this field in Europe.

  8. Calibration facility for environment dosimetry instruments

    NASA Astrophysics Data System (ADS)

    Bercea, Sorin; Celarel, Aurelia; Cenusa, Constantin

    2013-12-01

    In the last ten years, the nuclear activities, as well as the major nuclear events (see Fukushima accident) had an increasing impact on the environment, merely by contamination with radioactive materials. The most conferment way to quickly identify the presence of some radioactive elements in the environment, is to measure the dose-equivalent rate H. In this situation, information concerning the values of H due only to the natural radiation background must exist. Usually, the values of H due to the natural radiation background, are very low (˜10-9 - 10-8 Sv/h). A correct measurement of H in this range involve a performing calibration of the measuring instruments in the measuring range corresponding to the natural radiation background lead to important problems due to the presence of the natural background itself the best way to overlap this difficulty is to set up the calibration stand in an area with very low natural radiation background. In Romania, we identified an area with such special conditions at 200 m dept, in a salt mine. This paper deals with the necessary requirements for such a calibration facility, as well as with the calibration stand itself. The paper includes also, a description of the calibration stand (and images) as well as the radiological and metrological parameters. This calibration facilities for environment dosimetry is one of the few laboratories in this field in Europe.

  9. TH-C-17A-03: Dynamic Visualization and Dosimetry of IMRT and VMAT Treatment Plans by Video-Rate Imaging of Cherenkov Radiation in Pure Water

    SciTech Connect

    Glaser, A; Andreozzi, J; Davis, S; Zhang, R; Fox, C; Gladstone, D; Pogue, B

    2014-06-15

    Purpose: A novel optical dosimetry technique for the QA and verification of intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) radiotherapy plans was investigated for the first time by capturing images of the induced Cherenkov radiation in water. Methods: An intensified CCD camera (ICCD) was used to acquire a two-dimensional (2D) projection image of the Cherenkov radiation induced by IMRT and VMAT plans, based on the Task Group 119 C-Shape geometry. Plans were generated using the Varian Eclipse treatment planning system (TPS) and delivered using 6 MV x-rays from a Varian TrueBeam Linear Accelerator (Linac) incident on a water tank. The ICCD acquisition was gated to the Linac, operated for single pulse imaging, and binned to a resolution of 512×512 pixels. The resulting videos were analyzed temporally for regions of interest (ROI) covering the planning target volume (PTV) and organ at risk (OAR) and summed to obtain an overall light distribution, which was compared to the expected dose distribution from the TPS using a gammaindex analysis. Results: The chosen camera settings resulted in data at 23.5 frames per second. Temporal intensity plots of the PTV and OAR ROIs confirmed the preferential delivery of dose to the PTV versus the OAR, and the gamma analysis yielded 95.2% and 95.6% agreement between the light distribution and expected TPS dose distribution based upon a 3% / 3 mm dose difference and distance-to-agreement criterion for the IMRT and VMAT plans respectively. Conclusion: The results from this initial study demonstrate the first documented use of Cherenkov radiation for optical dosimetry of dynamic IMRT and VMAT treatment plans. The proposed modality has several potential advantages over alternative methods including the real-time nature of the acquisition, and upon future refinement may prove to be a robust and novel dosimetry method with both research and clinical applications. NIH R01CA109558 and R21EB017559.

  10. Changes in Functional Lung Regions During the Course of Radiation Therapy and Their Potential Impact on Lung Dosimetry for Non-Small Cell Lung Cancer

    SciTech Connect

    Meng, Xue; Frey, Kirk; Matuszak, Martha; Paul, Stanton; Ten Haken, Randall; Yu, Jinming; Kong, Feng-Ming

    2014-05-01

    Purpose: To study changes in functional activity on ventilation (V)/perfusion (Q) single-photon emission computed tomography (SPECT) during radiation therapy (RT) and explore the impact of such changes on lung dosimetry in patients with non-small cell lung cancer (NSCLC). Methods and Materials: Fifteen NSCLC patients with centrally located tumors were enrolled. All patients were treated with definitive RT dose of ≥60 Gy. V/Q SPECT-CT scans were performed prior to and after delivery of 45 Gy of fractionated RT. SPECT images were used to define temporarily dysfunctional regions of lung caused by tumor or other potentially reversible conditions as B3. The functional lung (FL) was defined on SPECT by 2 separate approaches: FL1, a threshold of 30% of the maximum uptake of the patient's lung; and FL2, FL1 plus B3 region. The impact of changes in FL between initiation of RT and delivery of 45 Gy on lung dosimetry were analyzed. Results: Fourteen patients (93%) had larger FL2 volumes than FL1 pre-RT (P<.001). Dysfunctional lung became functional in 11 patients (73%) on V SPECT and in 10 patients (67%) on Q SPECT. The dosimetric parameters generated from CT-based anatomical lung had significantly lower values in FL1 than FL2, with a median reduction in the volume of lung receiving a dose of at least 20 Gy (V{sub 20}) of 3%, 5.6%, and mean lung dose of 0.95 and 1.55 on V and Q SPECT respectively. Conclusions: Regional ventilation and perfusion function improve significantly during RT in centrally located NSCLC. Lung dosimetry values vary notably between different definitions of functional lung.

  11. Dosimetry in diagnostic radiology.

    PubMed

    Meghzifene, Ahmed; Dance, David R; McLean, Donald; Kramer, Hans-Michael

    2010-10-01

    Dosimetry is an area of increasing importance in diagnostic radiology. There is a realisation amongst health professionals that the radiation dose received by patients from modern X-ray examinations and procedures can be at a level of significance for the induction of cancer across a population, and in some unfortunate instances, in the acute damage to particular body organs such as skin and eyes. The formulation and measurement procedures for diagnostic radiology dosimetry have recently been standardised through an international code of practice which describes the methodologies necessary to address the diverging imaging modalities used in diagnostic radiology. Common to all dosimetry methodologies is the measurement of the air kerma from the X-ray device under defined conditions. To ensure the accuracy of the dosimetric determination, such measurements need to be made with appropriate instrumentation that has a calibration that is traceable to a standards laboratory. Dosimetric methods are used in radiology departments for a variety of purposes including the determination of patient dose levels to allow examinations to be optimized and to assist in decisions on the justification of examination choices. Patient dosimetry is important for special cases such as for X-ray examinations of children and pregnant patients. It is also a key component of the quality control of X-ray equipment and procedures. PMID:20655679

  12. Principles for the design and calibration of radiation protection dosemeters for operational and protection quantities for eye lens dosimetry.

    PubMed

    Bordy, J M; Gualdrini, G; Daures, J; Mariotti, F

    2011-03-01

    The work package two of the ORAMED project--Collaborative Project (2008-2011) supported by the European Commission within its seventh Framework Programme--is devoted to the study of the eye lens dosimetry. A first approach is to implement the use of H(p)(3) by providing new sets of conversion coefficients and well suited calibration and type test procedures. This approach is presented in other papers in the proceedings of this conference. Taking into account that the eye lens is an organ close to the surface of the body, another approach would be to directly estimate the absorbed dose to the eye lens, D(lens,est) through a special calibration procedure although this quantity is not directly measurable. This paper is a methodological paper that tries to identify the critical aspects of a dosimetry in terms of D(lens).

  13. Pilot test of ANSI draft standard N13.29 environmental dosimetry -- Performance criteria for testing

    SciTech Connect

    Klemic, G.; Shebell, P.; Monetti, M.; Raccah, F.; Shobe, J.; Lamperti, P.; Soares, C.; Sengupta, S.

    1998-09-01

    American National Standards Institute Draft N13.29 describes performance tests for environmental radiation dosimetry providers. If approved it would be the first step toward applying the types of performance testing now required in personnel dosimetry to environmental radiation monitoring. The objective of this study was to pilot test the draft standard, before it undergoes final balloting, on a small group of dosimetry providers that were selected to provide a mix of facility types, thermoluminescent dosimeter designs and monitoring program applications. The first phase of the pilot test involved exposing dosimeters to laboratory photon, beta, and x-ray sources at routine and accident dose levels. In the second phase, dosimeters were subjected to ninety days of simulated environmental conditions in an environmental chamber that cycled through extremes of temperature and humidity. Two out of seven participants passed all categories of the laboratory testing phase, and all seven passed the environmental test phase. While some relatively minor deficiencies were uncovered in the course of the pilot test, the results show that draft N13.29 describes useful tests that could be appropriate for environmental dosimetry providers. An appendix to this report contains recommendations that should be addressed by the N13.29 working group before draft N13.29 is submitted for balloting.

  14. An evaluation of the external radiation exposure dosimetry and calculation of maximum permissible concentration values for airborne materials containing 18F, 15O, 13N, 11C and 133Xe.

    PubMed

    Piltingsrud, H V; Gels, G L

    1985-11-01

    To better understand the dose equivalent (D.E.) rates produced by airborne releases of gaseous positron-emitting radionuclides under various conditions of cloud size, a study of the external radiation exposure dosimetry of these radionuclides, as well as negatron, gamma and x-ray emitting 133Xe, was undertaken. This included a calculation of the contributions to D.E. as a function of cloud radii, at tissue depths of 0.07 mm (skin), 3 mm (lens of eye) and 10 mm (whole body) from both the particulate and photon radiations emitted by these radionuclides. Estimates of maximum permissible concentration (MPC) values were also calculated based on the calculated D.E. rates and current regulations for personnel radiation protection (CFR84). Three continuous air monitors, designed for use with 133Xe, were evaluated for applications in monitoring air concentrations of the selected positron emitters. The results indicate that for a given radionuclide and for a cloud greater than a certain radius, personnel radiation dosimeters must respond acceptably to only the photon radiations emitted by the radionuclide to provide acceptable personnel dosimetry. For clouds under that radius, personnel radiation dosimeters must also respond acceptably to the positron or negatron radiations to provide acceptable personnel dosimetry. It was found that two out of the three air concentration monitors may be useful for monitoring air concentrations of the selected positron emitters.

  15. Development and characterization of remote radiation dosimetry systems using optically stimulated luminescence of alumina:carbon and potassium bromide:europium

    NASA Astrophysics Data System (ADS)

    Klein, David Matthew

    Scope and Method of Study. To develop and test the performance of two different dosimetry systems; one for in situ, high-sensitivity, inexpensive environmental monitoring, and another for near-real-time medical dosimetry. The systems are based on remote interrogation of the optically stimulated luminescence (OSL) from Al2O3:C and KBr:Eu single crystal dosimeters (exposed to environmental and medical radiation fields, respectively) via fiber optic cables. The environmental system was tested in lab conditions using various radioactive sources including 60Co, 90 Sr, 137Cs, and 226Ra, as well as with 232Th-enriched soil stimulant. The medical system was tested under various diagnostic x-ray systems, including fluoroscopy and computed tomography (CT) machines, as well as with high dose rate 192Ir brachytherapy sources and 232 MeV proton therapy beams under simulated treatment conditions. Findings and Conclusions. The environmental system was shown to achieve sensitivity high enough for measuring an OSL signal resulting from a dose of ˜1 muGy, which is equivalent to ˜12 hours of natural background radiation. This sensitivity allows for monitoring of the radiation characteristics of a natural environment more rapidly and/or less expensively than existing methods, such as soil sampling and in situ gamma spectroscopy. The KBr:Eu-based medical system results show that the near-real-time data acquisition during irradiation allows for rapid quality assurance (QA) measurements that benefits from high spatial resolution. These features are not present in most current standard dosimeters such as thermoluminescent detectors and pencil ionization chambers. The dosimeter does exhibit energy dependence, and a sensitization during high dose rate procedures. As a result, a model has been proposed that provides a description of the possible mechanisms that govern the transfer of electrons and holes within KBr:Eu during OSL measurement at room temperature. Correction factors for these

  16. Dosimetry in Nuclear Medicine Diagnosis and Therapy

    NASA Astrophysics Data System (ADS)

    Noßke, D.; Mattsson, S.; Johansson, L.

    This document is part of Subvolume A 'Fundamentals and Data in Radiobiology, Radiation Biophysics, Dosimetry and Medical Radiological Protection' of Volume 7 'Medical Radiological Physics' of Landolt-Börnstein - Group VIII 'Advanced Materials and Technologies'. It contains the Section '4.7 Necessity of Patient-Specific Dose Planning in Radionuclide Therapy' of the Chapter '4 Dosimetry in Nuclear Medicine Diagnosis and Therapy'.

  17. Laser-based flow cytometric analysis of genotoxicity of humans exposed to ionizing radiation during the Chernobyl accident

    SciTech Connect

    Jensen, R.H.; Bigbee, W.L.; Langlois, R.G.; Grant, S.G. ); Pleshanov, P.G. ); Chirkov, A.A. ); Pilinskaya, M.A. )

    1990-09-12

    An analytical technique has been developed that allows laser-based flow cytometric measurement of the frequency of red blood cells that have lost allele-specific expression of a cell surface antigen due to genetic toxicity in bone marrow precursor cells. Previous studies demonstrated a correlation of such effects with the exposure of each individual to mutagenic phenomena, such as ionizing radiation, and the effects can persist for the lifetime of each individual. During the emergency response to the nuclear power plant accident at Chernobyl, Ukraine, USSR, a number of people were exposed to whole body doses of ionizing radiation. Some of these individuals were tested with this laser-based assay and found to express a dose-dependent increase in the frequency of variant red blood cells that appears to be a persistent biological effect. All data indicate that this assay might well be used as a biodosimeter to estimate radiation dose and also as an element to be used for estimating the risk of each individual to develop cancer due to radiation exposure. 17 refs., 5 figs.

  18. Electron paramagnetic resonance radiation dose assessment in fingernails of the victim exposed to high dose as result of an accident.

    PubMed

    Romanyukha, Alexander; Trompier, François; Reyes, Ricardo A; Christensen, Doran M; Iddins, Carol J; Sugarman, Stephen L

    2014-11-01

    In this paper, we report results of radiation dose measurements in fingernails of a worker who sustained a radiation injury to his right thumb while using 130 kVp X-ray for nondestructive testing. Clinically estimated absorbed dose was about 20-25 Gy. Electron paramagnetic resonance (EPR) dose assessment was independently carried out by two laboratories, the Naval Dosimetry Center (NDC) and French Institut de Radioprotection et de Sûreté Nucléaire (IRSN). The laboratories used different equipments and protocols to estimate doses in the same fingernail samples. NDC used an X-band transportable EPR spectrometer, e-scan produced by Bruker BioSpin, and a universal dose calibration curve. In contrast, IRSN used a more sensitive Q-band stationary spectrometer (EMXplus) with a new approach for the dose assessment (dose saturation method), derived by additional dose irradiation to known doses. The protocol used by NDC is significantly faster than that used by IRSN, nondestructive, and could be done in field conditions, but it is probably less accurate and requires more sample for the measurements. The IRSN protocol, on the other hand, potentially is more accurate and requires very small amount of sample but requires more time and labor. In both EPR laboratories, the intense radiation-induced signal was measured in the accidentally irradiated fingernails and the resulting dose assessments were different. The dose on the fingernails from the right thumb was estimated as 14 ± 3 Gy at NDC and as 19 ± 6 Gy at IRSN. Both EPR dose assessments are given in terms of tissue kerma. This paper discusses the experience gained by using EPR for dose assessment in fingernails with a stationary spectrometer versus a portable one, the reasons for the observed discrepancies in dose, and potential advantages and disadvantages of each approach for EPR measurements in fingernails.

  19. Technical Basis Document for PFP Area Monitoring Dosimetry Program

    SciTech Connect

    COOPER, J.R.

    2000-04-17

    This document describes the phantom dosimetry used for the PFP Area Monitoring program and establishes the basis for the Plutonium Finishing Plant's (PFP) area monitoring dosimetry program in accordance with the following requirements: Title 10, Code of Federal Regulations (CFR), part 835, ''Occupational Radiation Protection'' Part 835.403; Hanford Site Radiological Control Manual (HSRCM-1), Part 514; HNF-PRO-382, Area Dosimetry Program; and PNL-MA-842, Hanford External Dosimetry Technical Basis Manual.

  20. Heavy-ion dosimetry

    SciTech Connect

    Schimmerling, W.

    1980-03-01

    This lecture deals with some of the more important physical characteristics of relativistic heavy ions and their measurement, with beam delivery and beam monitoring, and with conventional radiation dosimetry as used in the operation of the BEVALAC biomedical facility for high energy heavy ions (Lyman and Howard, 1977; BEVALAC, 1977). Even so, many fundamental aspects of the interaction of relativistic heavy ions with matter, including important atomic physics and radiation chemical considerations, are not discussed beyond the reminder that such additional understanding is required before an adequte perspective of the problem can be attained.

  1. Use of aspartame-based sweetener tablets in emergency dosimetry using EPR.

    PubMed

    Maghraby, A; Salama, E

    2010-06-01

    Accident dosimetry aims to evaluate the unplanned radiation doses delivered to individuals through one of the objects exist in the area of the accident. The gamma dose response of free radicals generated in irradiated aspartame tablets and its usability for emergency dosimetry was studied. EPR spectra of unirradiated and irradiated aspartame-based sweetener were recorded. Two signals arise after irradiating, S(1) at g (S(1)) = 2.00229 +/- 0.00097 and S(2) at g (S(2)) = 2.00262 +/- 0.00088. Some EPR parameters were studied for radiation-induced radicals in aspartame sweeteners tablets, such as the microwave saturation behaviour, the effect of magnetic field modulation amplitude on the peak-to-peak height and peak-to-peak line width for both of S(1) and S(2). Responses of S(1) and S(2) to different radiation doses were studied and resulted in linear relationships, radicals persistence curves were plotted over a 49-d storage period. It was found that Aspartame sweeteners tablets are useful in the range from 0.96 to 39.96 Gy. Radiation-induced radicals possess reasonable stability.

  2. Design and operation of a whole-body monitoring system for the Goiania radiation accident

    SciTech Connect

    Oliveira, C.A.; Lourenco, M.C.; Dantas, B.M.; Lucena, E.A. )

    1991-01-01

    With as many individuals involved in the Goiania 137Cs accident who had high levels of internal contamination, it was necessary to improvise a whole-body counter installation in loco. The in-vivo counting system was located in a 4.0 X 3.5 X 3.5-m room, where seven layers of 2-mm lead sheets with dimensions of 2.0 m X 1.0 m were overlaid on the floor at loci that were equidistant from the walls. A 20-cm diameter NaI (Tl) detector was installed at a height of 2.05 m above the floor at the center of the room. The detector was shielded and collimated with 5 cm of lead. The enormous amounts of activity in the subjects required the detector to be positioned at a height of 2.05 m. Subjects were required to wear disposable clothing and lie on a reclining, fiberglass chair. Counting time for the subjects was 2 min (live-time). The minimum detectable 137Cs activity for this counting time was 7.3 kBq* (0.05 significance level). Besides the accident victims, all individuals who had direct or indirect contact with contaminated people or areas were also monitored. More than 300 people of both sexes, with ages varying from a few months to 72 y, were measured for whole-body radioactivity. The observed activities ranged from less than the minimum detectable activity (MDA) to 59 MBq.

  3. Radiation risk models for all solid cancers other than those types of cancer requiring individual assessments after a nuclear accident.

    PubMed

    Walsh, Linda; Zhang, Wei

    2016-03-01

    In the assessment of health risks after nuclear accidents, some health consequences require special attention. For example, in their 2013 report on health risk assessment after the Fukushima nuclear accident, the World Health Organisation (WHO) panel of experts considered risks of breast cancer, thyroid cancer and leukaemia. For these specific cancer types, use was made of already published excess relative risk (ERR) and excess absolute risk (EAR) models for radiation-related cancer incidence fitted to the epidemiological data from the Japanese A-bomb Life Span Study (LSS). However, it was also considered important to assess all other types of solid cancer together and the WHO, in their above-mentioned report, stated "No model to calculate the risk for all other solid cancer excluding breast and thyroid cancer risks is available from the LSS data". Applying the LSS models for all solid cancers along with the models for the specific sites means that some cancers have an overlap in the risk evaluations. Thus, calculating the total solid cancer risk plus the breast cancer risk plus the thyroid cancer risk can overestimate the total risk by several per cent. Therefore, the purpose of this paper was to publish the required models for all other solid cancers, i.e. all solid cancers other than those types of cancer requiring special attention after a nuclear accident. The new models presented here have been fitted to the same LSS data set from which the risks provided by the WHO were derived. Although it is known already that the EAR and ERR effect modifications by sex are statistically significant for the outcome "all solid cancer", it is shown here that sex modification is not statistically significant for the outcome "all solid cancer other than thyroid and breast cancer". It is also shown here that the sex-averaged solid cancer risks with and without the sex modification are very similar once breast and thyroid cancers are factored out. Some other notable model

  4. Radiation risk models for all solid cancers other than those types of cancer requiring individual assessments after a nuclear accident.

    PubMed

    Walsh, Linda; Zhang, Wei

    2016-03-01

    In the assessment of health risks after nuclear accidents, some health consequences require special attention. For example, in their 2013 report on health risk assessment after the Fukushima nuclear accident, the World Health Organisation (WHO) panel of experts considered risks of breast cancer, thyroid cancer and leukaemia. For these specific cancer types, use was made of already published excess relative risk (ERR) and excess absolute risk (EAR) models for radiation-related cancer incidence fitted to the epidemiological data from the Japanese A-bomb Life Span Study (LSS). However, it was also considered important to assess all other types of solid cancer together and the WHO, in their above-mentioned report, stated "No model to calculate the risk for all other solid cancer excluding breast and thyroid cancer risks is available from the LSS data". Applying the LSS models for all solid cancers along with the models for the specific sites means that some cancers have an overlap in the risk evaluations. Thus, calculating the total solid cancer risk plus the breast cancer risk plus the thyroid cancer risk can overestimate the total risk by several per cent. Therefore, the purpose of this paper was to publish the required models for all other solid cancers, i.e. all solid cancers other than those types of cancer requiring special attention after a nuclear accident. The new models presented here have been fitted to the same LSS data set from which the risks provided by the WHO were derived. Although it is known already that the EAR and ERR effect modifications by sex are statistically significant for the outcome "all solid cancer", it is shown here that sex modification is not statistically significant for the outcome "all solid cancer other than thyroid and breast cancer". It is also shown here that the sex-averaged solid cancer risks with and without the sex modification are very similar once breast and thyroid cancers are factored out. Some other notable model

  5. Development of a personal dosimetry system based on optically stimulated luminescence of alpha-Al2O3:C for mixed radiation fields.

    PubMed

    Lee, S Y; Lee, K J

    2001-04-01

    To develop a personal optically stimulated luminescence (OSL) dosimetry system for mixed radiation fields using alpha-Al2O3:C, a discriminating badge filter system was designed by taking advantage of its optically stimulable properties and energy dependencies. This was done by designing a multi-element badge system for powder layered alpha-Al2O3:C material and an optical reader system based on high-intensity blue light-emitting diode (LED). The design of the multielement OSL dosimeter badge system developed allows the measurement of a personal dose equivalent value Hp(d) in mixed radiation fields of beta and gamma. Dosimetric properties of the personal OSL dosimeter badge system investigated here were the dose response, energy response and multi-readability. Based on the computational simulations and experiments of the proposed dosimeter design, it was demonstrated that a multi-element dosimeter system with an OSL technology based on alpha-Al2O3:C is suitable to obtain personal dose equivalent information in mixed radiation fields. PMID:11225704

  6. Development of a new positron emission tomography tracer for targeting tumor angiogenesis: synthesis, small animal imaging, and radiation dosimetry.

    PubMed

    Patterson, Cam; Frederick, C Brandon; Yuan, Hong; Dyer, Laura A; Lockyer, Pamela; Lalush, David S; Veleva, Anka N

    2013-05-15

    Angiogenesis plays a key role in cancer progression and correlates with disease aggressiveness and poor clinical outcomes. Affinity ligands discovered by screening phage display random peptide libraries can be engineered to molecularly target tumor blood vessels for noninvasive imaging and early detection of tumor aggressiveness. In this study, we tested the ability of a phage-display-selected peptide sequence recognizing specifically bone marrow- derived pro-angiogenic tumor-homing cells, the QFP-peptide, radiolabeled with 64Cu radioisotope to selectively image tumor vasculature in vivo by positron emission tomography (PET). To prepare the targeted PET tracer we modified QFP-phage with the DOTA chelator and radiolabeled the purified QFP-phage-DOTA intermediate with 64Cu to obtain QFP-targeted radioconjugate with high radiopharmaceutical yield and specific activity. We evaluated the new PET tracer in vivo in a subcutaneous (s.c.) Lewis lung carcinoma (LLC) mouse model and conducted tissue distribution, small animal PET/CT imaging study, autoradiography, histology, fluorescence imaging, and dosimetry assessments. The results from this study show that, in the context of the s.c. LLC immunocompetent mouse model, the QFP-tracer can target tumor blood vessels selectively. However, further optimization of the biodistribution and dosimetry profile of the tracer is necessary to ensure efficient radiopharmaceutical applications enabled by the biological specificity of the QFP-peptide.

  7. Neutron personnel dosimetry

    SciTech Connect

    Griffith, R.V.

    1981-06-16

    The current state-of-the-art in neutron personnel dosimetry is reviewed. Topics covered include dosimetry needs and alternatives, current dosimetry approaches, personnel monitoring devices, calibration strategies, and future developments. (ACR)

  8. Development of Fast and Highly Efficient Gas Ionization Chamber For Patient Imaging and Dosimetry in Radiation Therapy

    SciTech Connect

    R. Hinderler; H. Keller; T.R. Mackie; M.L. Corradini

    2003-09-08

    In radiation therapy of cancer, more accurate delivery techniques spur the need for improved patient imaging during treatment. To this purpose, the megavoltage radiation protocol that is used for treatment is also used for imaging.

  9. Dosimetry for Radiopharmaceutical Therapy

    PubMed Central

    Sgouros, George; Hobbs, Robert F.

    2014-01-01

    Radiopharmaceutical therapy (RPT) involves the use of radionuclides that are either conjugated to tumor-targeting agents (eg, nanoscale constructs, antibodies, peptides, and small molecules) or concentrated in tissue through natural physiological mechanisms that occur predominantly in neoplastic or otherwise targeted cells (eg, Graves disease). The ability to collect pharmacokinetic data by imaging and use this to perform dosimetry calculations for treatment planning distinguishes RPT from other systemic treatment modalities. Treatment planning has not been widely adopted, in part, because early attempts to relate dosimetry to outcome were not successful. This was partially because a dosimetry methodology appropriate to risk evaluation rather than efficacy and toxicity was being applied to RPT. The weakest links in both diagnostic and therapeutic dosimetry are the accuracy of the input and the reliability of the radiobiological models used to convert dosimetric data to the relevant biologic end points. Dosimetry for RPT places a greater demand on both of these weak links. To date, most dosimetric studies have been retrospective, with a focus on tumor dose-response correlations rather than prospective treatment planning. In this regard, transarterial radioembolization also known as intra-arterial radiation therapy, which uses radiolabeled (90Y) microspheres of glass or resin to treat lesions in the liver holds much promise for more widespread dosimetric treatment planning. The recent interest in RPT with alpha-particle emitters has highlighted the need to adopt a dosimetry methodology that specifically accounts for the unique aspects of alpha particles. The short range of alpha-particle emitters means that in cases in which the distribution of activity is localized to specific functional components or cell types of an organ, the absorbed dose will be equally localized and dosimetric calculations on the scale of organs or even voxels (~5 mm) are no longer sufficient

  10. Kevlar® as a Potential Accident Radiation Dosimeter for First Responders, Law Enforcement and Military Personnel.

    PubMed

    Romanyukha, Alexander; Trompier, François; Benevides, Luis A

    2016-08-01

    Today the armed forces and law enforcement personnel wear body armor, helmets, and flak jackets composed substantially of Kevlar® fiber to prevent bodily injury or death resulting from physical, ballistic, stab, and slash attacks. Therefore, there is a high probability that during a radiation accident or its aftermath, the Kevlar®-composed body armor will be irradiated. Preliminary study with samples of Kevlar® foundation fabric obtained from body armor used by the U.S. Marine Corps has shown that all samples evaluated demonstrated an EPR signal, and this signal increased with radiation dose. Based on these results, the authors predict that, with individual calibration, exposure at dose above 1 Gy can be reliably detected in Kevlar® samples obtained from body armor. As a result of these measurements, a post-event reconstruction of exposure dose can be obtained by taking various samples throughout the armor body and helmet worn by the same irradiated individual. The doses can be used to create a whole-body dose map that would be of vital importance in a case of a partial body or heterogeneous exposure.

  11. Radiation Monitoring using an Unmanned Helicopter in the Evacuation Zone Set up by the Fukushima Daiichi NPP Accident.

    NASA Astrophysics Data System (ADS)

    Torii, Tatsuo; Sanada, Yukihisa; Nishizawa, Yukiyasu; Kondo, Atsuya; Shoji, Yasunori; ikeda, Kazutaka

    2013-04-01

    By the nuclear accident of the Fukushima Daiichi Nuclear Power Plant (NPP) caused by the East Japan earthquake and the following tsunami occurred on March 11, 2011, a large amount of radioactive materials was released from the NPP. In recent years, technologies for an unmanned helicopter have been developed and applied to natural disasters. In expectation of the application of the unmanned helicopter to airborne radiation monitoring, we had developed a radiation monitoring system using an autonomous unmanned helicopter (AUH). Then, we measured the ambient dose-rate at the height of 1-m above the ground and the soil deposition of radioactive cesium (Cs-134, Cs-137) by using the AUH system in the evacuation zone of residents around the NPP. Here, we report on the measurement technique and the result. As a result measured around a river at 10-km away from the NPP, high contaminated areas compared with the circumstance are detected along the dry riverbed. It was seemed that it had flowed along the river from highly contaminated areas in the upper stream.

  12. Severe accident thermal analyses of a PWR with in-vessel radiation/convection and external flooding

    SciTech Connect

    Hawkes, G.L.; O`Brien, J.E.

    1992-08-01

    A severe accident thermal analysis has been performed to study the effect of thermal radiation from the upper surface of a relocated molten core to the vessel inner walls and vessel internals. External water flooding has been included as a means of cooling the vessel to prevent thermal failure. A finite element gray body radiation model is used to predict radiant heat transfer from the molten core to the vessel wall, core barrel, reflector shield, and fuel assemblies of a partially melted and partially relocated core with decay heat. Parametric studies have been performed in which variations in the emissivity of the core crust, vessel wall, fuel assemblies, and other vessel internals have been considered. Other parameters considered included the flooding water level, and vessel upper structure radiant temperature. A finite element computational fluid dynamics model of hydrogen turbulent natural convection inside the vessel is included. The effect of a metallic layer overlying the relocated ceramic core has also been considered. Inside vessel wall temperatures were predicted to be excess of the melting point for some cases. These studies show that vessel integrity is mainly dependent upon the height of the flooding water on the vessel exterior.

  13. Severe accident thermal analyses of a PWR with in-vessel radiation/convection and external flooding

    SciTech Connect

    Hawkes, G.L.; O'Brien, J.E.

    1992-01-01

    A severe accident thermal analysis has been performed to study the effect of thermal radiation from the upper surface of a relocated molten core to the vessel inner walls and vessel internals. External water flooding has been included as a means of cooling the vessel to prevent thermal failure. A finite element gray body radiation model is used to predict radiant heat transfer from the molten core to the vessel wall, core barrel, reflector shield, and fuel assemblies of a partially melted and partially relocated core with decay heat. Parametric studies have been performed in which variations in the emissivity of the core crust, vessel wall, fuel assemblies, and other vessel internals have been considered. Other parameters considered included the flooding water level, and vessel upper structure radiant temperature. A finite element computational fluid dynamics model of hydrogen turbulent natural convection inside the vessel is included. The effect of a metallic layer overlying the relocated ceramic core has also been considered. Inside vessel wall temperatures were predicted to be excess of the melting point for some cases. These studies show that vessel integrity is mainly dependent upon the height of the flooding water on the vessel exterior.

  14. Analysis of current assessments and perspectives of ESR tooth dosimetry for radiation dose reconstruction of the population residing near the Semipalatinsk nuclear test site.

    PubMed

    Romanyukha, Alex; Schauer, David A; Malikov, Yurii K

    2006-02-01

    Between 1949 and 1989 the Semipalatinsk nuclear test site (SNTS), an area of 19,000 square km in northeastern Kazakhstan, was the location of over 400 nuclear test explosions with a total explosive energy of 6.6 Mt TNT (trinitrotoluene or trotyl) equivalent. It is estimated that the bulk of the radiation exposure to the population resulted from three tests, conducted in 1949, 1951, and 1953 although estimations of radiation doses received by the local population have varied significantly. Analysis of the published ESR dose reconstruction results for residents of the villages near the SNTS show that they do not correlate well with other methods of dose assessment (e.g. model dose calculation and thermo luminescence dosimetry (TLD) in bricks). The most significant difference in dose estimations was found for the population of Dolon, which was exposed as result of the first Soviet nuclear test in 1949. Published results of ESR measurements in tooth enamel are considerably lower than other dose estimations. Detailed analysis of these results is provided and a possible explanation for this discrepancy and ways to eliminate it are suggested.

  15. Recommended improvements to the DS02 dosimetry system's calculation of organ doses and their potential advantages for the Radiation Effects Research Foundation.

    PubMed

    Cullings, Harry M

    2012-03-01

    The Radiation Effects Research Foundation (RERF) uses a dosimetry system to calculate radiation doses received by the Japanese atomic bomb survivors based on their reported location and shielding at the time of exposure. The current system, DS02, completed in 2003, calculates detailed doses to 15 particular organs of the body from neutrons and gamma rays, using new source terms and transport calculations as well as some other improvements in the calculation of terrain and structural shielding, but continues to use methods from an older system, DS86, to account for body self-shielding. Although recent developments in models of the human body from medical imaging, along with contemporary computer speed and software, allow for improvement of the calculated organ doses, before undertaking changes to the organ dose calculations, it is important to evaluate the improvements that can be made and their potential contribution to RERF's research. The analysis provided here suggests that the most important improvements can be made by providing calculations for more organs or tissues and by providing a larger series of age- and sex-specific models of the human body from birth to adulthood, as well as fetal models. PMID:22262817

  16. Dosimetry measurements of x-ray and neutron radiation levels near the shuttle and end beam dump at the advanced test accelerator: Beam Research Program

    SciTech Connect

    Gibson, T.A. Jr.; Struve, K.W.; Lindgren, R.A.

    1987-01-01

    Electron beams as a source of directed energy are under study at the Lawrence Livermore National Laboratory (LLNL). An intense 10-kA, 50-MeV, 50-ns full-width half-maximum, pulsed electron beam is generated by the prototype Advanced Test Accelerator (ATA) at the Laboratory's Site 300. Whenever the electron beam is stopped in materials, intense radiation is generated. Estimates based on available data in the literature show that for materials such as lead, photon radiation (x ray, gamma, bremsstrahlung) levels can be as large as 10/sup 4/ roentgens per pulse at 1 m in the zero-degree direction (i.e., the electron-beam direction). Neutrons, which are emitted isotropically, are produced at a level of 10/sup 13/ n/m/sup 2/ per pulse. Depending upon the number of pulses and the shielding geometry, the accumulated dose is potentially lethal to personnel and potentially damaging to instrumentation that may be used for diagnostics. To provide shielding for minimizing the risk of exposure to personnel and radiation damage to instrumentation, it is important to determine the x-ray and neutron radiation environment near beamline components such as the beam shuttle dump and beam stop. Photon and neutron dosimetry measurements were performed around the beam shuttle dump on January 9, 1985, and near the carbon beam stop at the end of the beamline before the entrance to the diagnostic tunnel on April 12 and December 23, 1985. These measurements together with simple rule-of-thumb estimates and Monte Carlo electron-photon shower calculations of the absorbed dose are presented in this report. 17 refs., 14 figs., 13 tabs.

  17. SU-F-18C-09: Assessment of OSL Dosimeter Technology in the Validation of a Monte Carlo Radiation Transport Code for CT Dosimetry

    SciTech Connect

    Carver, D; Kost, S; Pickens, D; Price, R; Stabin, M

    2014-06-15

    Purpose: To assess the utility of optically stimulated luminescent (OSL) dosimeter technology in calibrating and validating a Monte Carlo radiation transport code for computed tomography (CT). Methods: Exposure data were taken using both a standard CT 100-mm pencil ionization chamber and a series of 150-mm OSL CT dosimeters. Measurements were made at system isocenter in air as well as in standard 16-cm (head) and 32-cm (body) CTDI phantoms at isocenter and at the 12 o'clock positions. Scans were performed on a Philips Brilliance 64 CT scanner for 100 and 120 kVp at 300 mAs with a nominal beam width of 40 mm. A radiation transport code to simulate the CT scanner conditions was developed using the GEANT4 physics toolkit. The imaging geometry and associated parameters were simulated for each ionization chamber and phantom combination. Simulated absorbed doses were compared to both CTDI{sub 100} values determined from the ion chamber and to CTDI{sub 100} values reported from the OSLs. The dose profiles from each simulation were also compared to the physical OSL dose profiles. Results: CTDI{sub 100} values reported by the ion chamber and OSLs are generally in good agreement (average percent difference of 9%), and provide a suitable way to calibrate doses obtained from simulation to real absorbed doses. Simulated and real CTDI{sub 100} values agree to within 10% or less, and the simulated dose profiles also predict the physical profiles reported by the OSLs. Conclusion: Ionization chambers are generally considered the standard for absolute dose measurements. However, OSL dosimeters may also serve as a useful tool with the significant benefit of also assessing the radiation dose profile. This may offer an advantage to those developing simulations for assessing radiation dosimetry such as verification of spatial dose distribution and beam width.

  18. Laser accidents: Being Prepared

    SciTech Connect

    Barat, K

    2003-01-24

    The goal of the Laser Safety Officer and any laser safety program is to prevent a laser accident from occurring, in particular an injury to a person's eyes. Most laser safety courses talk about laser accidents, causes, and types of injury. The purpose of this presentation is to present a plan for safety offices and users to follow in case of accident or injury from laser radiation.

  19. Spatiotemporal characteristics of internal radiation exposure in evacuees and first responders after the radiological accident in fukushima.

    PubMed

    Morita, Naoko; Miura, Miwa; Yoshida, Masahiro; Kumagai, Atsushi; Ohtsuru, Akira; Usa, Toshiro; Kudo, Takashi; Takamura, Noboru; Yamashita, Shunichi; Matsuda, Naoki

    2013-09-01

    After the Tokyo Electric Power Company Fukushima Daiichi nuclear power plant accident on March 11, 2011, the reconstruction of early internal radiation doses in residents of Fukushima plays a major role in evaluating their future heath risk, including thyroid cancer by internal radioiodine. Internal radioactivity was measured using a whole body counter (WBC) at the Nagasaki University Medical School to evaluate the health risks of residents and short term visitors in Fukushima. Measurable (131)I, (134)Cs and (137)Cs were detected altogether in 49 out of 196 people who were in Fukushima prefecture at any time during March 11 and April 20, 2011. In 49 people, the 90 percentile of the thyroid equivalent dose by (131)I and the committed effective dose (total effective dose over a lifetime) by the sum of (134)Cs and (137)Cs was 3 mSv and 0.06 mSv, respectively. The radionuclide intakes in early evacuees who left Fukushima before March 16 were more than five times as high as in the responders who moved to Fukushima later. The intake ratio of (131)I/(137)Cs of the earlier evacuees was approximately three. The spatial analysis of 16 evacuees to the south indicated a reduction of internal radioactivity depending on the distance from the nuclear power plant. Among them, high internal (131)I radioactivity in 6 people in a particular evacuation route could be explained by the arrival of a radioactive cloud with a high airborne (131)I/(137)Cs ratio to the environment, as predicted by atmospheric dispersion simulations. Overall, the actual internal radioactivity assessed by a WBC examination comparatively agreed with the predicted airborne radioactivity. These results suggest that the accurate estimation of internal doses in the first week after the radiological accident is critical for the dose reconstruction. The evaluation of internal doses of residents based on their evacuation routes and the advanced estimation of airborne radioactivity from the atmospheric dispersion model

  20. Uranium Dispersion & Dosimetry Model.

    SciTech Connect

    MICHAEL,; MOMENI, H.

    2002-03-22

    The Uranium Dispersion and Dosimetry (UDAD) program provides estimates of potential radiation exposure to individuals and to the general population in the vicinity of a uranium processing facility such as a uranium mine or mill. Only transport through the air is considered. Exposure results from inhalation, external irradiation from airborne and ground-deposited activity, and ingestion of foodstuffs. Individual dose commitments, population dose commitments, and environmental dose commitments are computed. The program was developed for application to uranium mining and milling; however, it may be applied to dispersion of any other pollutant.

  1. Uranium Dispersion & Dosimetry Model.

    2002-03-22

    The Uranium Dispersion and Dosimetry (UDAD) program provides estimates of potential radiation exposure to individuals and to the general population in the vicinity of a uranium processing facility such as a uranium mine or mill. Only transport through the air is considered. Exposure results from inhalation, external irradiation from airborne and ground-deposited activity, and ingestion of foodstuffs. Individual dose commitments, population dose commitments, and environmental dose commitments are computed. The program was developed for applicationmore » to uranium mining and milling; however, it may be applied to dispersion of any other pollutant.« less

  2. Fast neutron dosimetry

    SciTech Connect

    DeLuca, P.M. Jr.; Pearson, D.W.

    1992-01-01

    This progress report concentrates on two major areas of dosimetry research: measurement of fast neutron kerma factors for several elements for monochromatic and white spectrum neutron fields and determination of the response of thermoluminescent phosphors to various ultra-soft X-ray energies and beta-rays. Dr. Zhixin Zhou from the Shanghai Institute of Radiation Medicine, People's Republic of China brought with him special expertise in the fabrication and use of ultra-thin TLD materials. Such materials are not available in the USA. The rather unique properties of these materials were investigated during this grant period.

  3. Radon Dosimetry and Monitoring in Mines

    NASA Astrophysics Data System (ADS)

    Pineau, J. F.

    The following sections are included: * Introduction * The Atmosphere in Underground Mines * Origin of the radioactivity of the atmosphere in underground mines * Main characteristics of the atmosphere of mines * Temperature * Relative humidity * Particle size distribution of the aerosols * Volume concentration of radon * Age of the ventilation air * Volume concentration of radon decay products * Volume concentration of long-lived aerosols (LLA) * Order of magnitude of the volume concentrations to be measured * Dosimetry: Application to Miners * Dosimetry of miners in France * Integrated dosimetry system * Measuring head * Unit for the detection and measurement of exposure to potential alpha energy * Treatment and reading of the detector films * Expression of the results * Other examples of operational dosimetry * Use of closed passive dosimeters for the dosimetry of miners * Monitoring of Physical Parameters of the Atmospheres * Qualification of non-uranium mines * Monitoring of the environment of mining sites * Optimisation of radiation protection using the dosimetric data * Concluding Remarks * References

  4. Proposed radiation hardened mobile vehicle for Chernobyl dismantlement and nuclear accident response

    SciTech Connect

    Rowland, M.S.; Holliday, M.A.; Karpachov, J.A.; Ivanov, A.

    1995-01-01

    Researchers are developing a radiation hardened, Telerobotic Dismantling System (TDS) to remediate the Chernobyl facility. To withstand the severe radiation fields, the robotic system, will rely on electrical motors, actuators, and relays proven in the Chernobyl power station. Due to its dust suppression characteristics and ability to cut arbitrary materials the authors propose using a water knife as the principle tool to slice up the large fuel containing masses. The front end of the robot will use a minimum number of moving parts by locating most of the susceptible and bulky components outside the work area. Hardened and shielded video cameras will be designed for remote control and viewing of the robotic functions. Operators will supervise and control robot movements based on feedback from a suite of sensory systems that would include vision systems, radiation detection and measurement systems and force reflection systems. A gripper will be instrumented with a variety of sensors (e.g. force, torque, or tactile), allowing varying debris surface properties to be grasped. The gripper will allow the operator to manipulate and segregate debris items without entering the radiologically and physically dangerous dismantlement operations area. The robots will initially size reduce the FCM`s to reduce the primary sources of the airborne radionuclides. The robot will then remove the high level waste for packaging or decontamination, and storage nearby.

  5. Radiation dose reduction efficiency of buildings after the accident at the Fukushima Daiichi Nuclear Power Station.

    PubMed

    Monzen, Satoru; Hosoda, Masahiro; Osanai, Minoru; Tokonami, Shinji

    2014-01-01

    Numerous radionuclides were released from the Fukushima Daiichi Nuclear Power Station (F1-NPS) in Japan following the magnitude 9.0 earthquake and tsunami on March 11, 2011. Local residents have been eager to calculate their individual radiation exposure. Thus, absorbed dose rates in the indoor and outdoor air at evacuation sites in the Fukushima Prefecture were measured using a gamma-ray measuring devices, and individual radiation exposure was calculated by assessing the radiation dose reduction efficiency (defined as the ratio of absorbed dose rate in the indoor air to the absorbed dose rate in the outdoor air) of wood, aluminum, and reinforced concrete buildings. Between March 2011 and July 2011, dose reduction efficiencies of wood, aluminum, and reinforced concrete buildings were 0.55 ± 0.04, 0.15 ± 0.02, and 0.19 ± 0.04, respectively. The reduction efficiency of wood structures was 1.4 times higher than that reported by the International Atomic Energy Agency. The efficiency of reinforced concrete was similar to previously reported values, whereas that of aluminum structures has not been previously reported. Dose reduction efficiency increased in proportion to the distance from F1-NPS at 8 of the 18 evacuation sites. Time variations did not reflect dose reduction efficiencies at evacuation sites although absorbed dose rates in the outdoor air decreased. These data suggest that dose reduction efficiency depends on structure types, levels of contamination, and evacuee behaviors at evacuation sites.

  6. Radiation Dose Reduction Efficiency of Buildings after the Accident at the Fukushima Daiichi Nuclear Power Station

    PubMed Central

    Monzen, Satoru; Hosoda, Masahiro; Osanai, Minoru; Tokonami, Shinji

    2014-01-01

    Numerous radionuclides were released from the Fukushima Daiichi Nuclear Power Station (F1-NPS) in Japan following the magnitude 9.0 earthquake and tsunami on March 11, 2011. Local residents have been eager to calculate their individual radiation exposure. Thus, absorbed dose rates in the indoor and outdoor air at evacuation sites in the Fukushima Prefecture were measured using a gamma-ray measuring devices, and individual radiation exposure was calculated by assessing the radiation dose reduction efficiency (defined as the ratio of absorbed dose rate in the indoor air to the absorbed dose rate in the outdoor air) of wood, aluminum, and reinforced concrete buildings. Between March 2011 and July 2011, dose reduction efficiencies of wood, aluminum, and reinforced concrete buildings were 0.55±0.04, 0.15±0.02, and 0.19±0.04, respectively. The reduction efficiency of wood structures was 1.4 times higher than that reported by the International Atomic Energy Agency. The efficiency of reinforced concrete was similar to previously reported values, whereas that of aluminum structures has not been previously reported. Dose reduction efficiency increased in proportion to the distance from F1-NPS at 8 of the 18 evacuation sites. Time variations did not reflect dose reduction efficiencies at evacuation sites although absorbed dose rates in the outdoor air decreased. These data suggest that dose reduction efficiency depends on structure types, levels of contamination, and evacuee behaviors at evacuation sites. PMID:24999992

  7. Radiation dose reduction efficiency of buildings after the accident at the Fukushima Daiichi Nuclear Power Station.

    PubMed

    Monzen, Satoru; Hosoda, Masahiro; Osanai, Minoru; Tokonami, Shinji

    2014-01-01

    Numerous radionuclides were released from the Fukushima Daiichi Nuclear Power Station (F1-NPS) in Japan following the magnitude 9.0 earthquake and tsunami on March 11, 2011. Local residents have been eager to calculate their individual radiation exposure. Thus, absorbed dose rates in the indoor and outdoor air at evacuation sites in the Fukushima Prefecture were measured using a gamma-ray measuring devices, and individual radiation exposure was calculated by assessing the radiation dose reduction efficiency (defined as the ratio of absorbed dose rate in the indoor air to the absorbed dose rate in the outdoor air) of wood, aluminum, and reinforced concrete buildings. Between March 2011 and July 2011, dose reduction efficiencies of wood, aluminum, and reinforced concrete buildings were 0.55 ± 0.04, 0.15 ± 0.02, and 0.19 ± 0.04, respectively. The reduction efficiency of wood structures was 1.4 times higher than that reported by the International Atomic Energy Agency. The efficiency of reinforced concrete was similar to previously reported values, whereas that of aluminum structures has not been previously reported. Dose reduction efficiency increased in proportion to the distance from F1-NPS at 8 of the 18 evacuation sites. Time variations did not reflect dose reduction efficiencies at evacuation sites although absorbed dose rates in the outdoor air decreased. These data suggest that dose reduction efficiency depends on structure types, levels of contamination, and evacuee behaviors at evacuation sites. PMID:24999992

  8. Returning land contaminated as a result of radiation accidents to farming use.

    PubMed

    Voronina, A V; Blinova, M O; Semenishchev, V S; Gupta, D K

    2015-06-01

    An assessment is given of the possibility of sorbents based on natural aluminosilicates (glauconite and clinoptilolite) being used for remediation of radioactively contaminated land with the aim of returning it to farming use. A comparative study of selectivity and reversibility of radiocaesium and radiostrontium sorption by natural aluminosilicates as well as by modified ferrocyanide sorbents based on these aluminosilicates was made. It was found that surface modification of aluminosilicates by ferrocyanides increases the selectivity of synthesized sorbents to caesium by 100-1000 times, increases sorption capacity and makes caesium sorption almost irreversible, whereas, selectivity of these sorbents to strontium radionuclides remains approximately the same as for natural aluminosilicates. The caesium distribution coefficient for mixed nickel-potassium ferrocyanide on glauconite is 10((5.0±0.6)) L kg(-1), the static exchange capacity (SEC) is 63 mg g(-1); for mixed nickel-potassium ferrocyanide based on clinoptilolite caesium distribution coefficients in various concentration ranges are 10((7.0±1.0)), 10((5.7±0.4)) and 10((3.2±0.7)) L kg(-1), total SEC was 500 mg g(-1). Caesium leaching by various leaching solutions from saturated mixed nickel-potassium ferrocyanide based on clinoptilolite was lower than 2%; from saturated mixed nickel-potassium ferrocyanide based on glauconite it was 1.5-14.6%. Ferrocyanide sorbents, based on glauconite and clinoptilolite are recommended for remediation of land, contaminated by caesium as a result of the Fukushima accident in Japan. Use of these sorbents should decrease the transfer of caesium to agricultural vegetation up to a factor of 20.

  9. Returning land contaminated as a result of radiation accidents to farming use.

    PubMed

    Voronina, A V; Blinova, M O; Semenishchev, V S; Gupta, D K

    2015-06-01

    An assessment is given of the possibility of sorbents based on natural aluminosilicates (glauconite and clinoptilolite) being used for remediation of radioactively contaminated land with the aim of returning it to farming use. A comparative study of selectivity and reversibility of radiocaesium and radiostrontium sorption by natural aluminosilicates as well as by modified ferrocyanide sorbents based on these aluminosilicates was made. It was found that surface modification of aluminosilicates by ferrocyanides increases the selectivity of synthesized sorbents to caesium by 100-1000 times, increases sorption capacity and makes caesium sorption almost irreversible, whereas, selectivity of these sorbents to strontium radionuclides remains approximately the same as for natural aluminosilicates. The caesium distribution coefficient for mixed nickel-potassium ferrocyanide on glauconite is 10((5.0±0.6)) L kg(-1), the static exchange capacity (SEC) is 63 mg g(-1); for mixed nickel-potassium ferrocyanide based on clinoptilolite caesium distribution coefficients in various concentration ranges are 10((7.0±1.0)), 10((5.7±0.4)) and 10((3.2±0.7)) L kg(-1), total SEC was 500 mg g(-1). Caesium leaching by various leaching solutions from saturated mixed nickel-potassium ferrocyanide based on clinoptilolite was lower than 2%; from saturated mixed nickel-potassium ferrocyanide based on glauconite it was 1.5-14.6%. Ferrocyanide sorbents, based on glauconite and clinoptilolite are recommended for remediation of land, contaminated by caesium as a result of the Fukushima accident in Japan. Use of these sorbents should decrease the transfer of caesium to agricultural vegetation up to a factor of 20. PMID:25827577

  10. Radiation and non-radiation factors and their impact on the natural history of coronary heart disease in Chornobyl accident clean-up workers.

    PubMed

    Bilyi, D O; Nastina, O M; Gabulavichene, Zh M; Sydorenko, G V; Bazyka, O D; Bilaya, V V; Kovalyov, O S

    2014-09-01

    The objective of the study was to evaluate the impact of a range of risk factors and ionizing radiation on the severity of clinical presentation of coronary heart disease (CHD) in Chornobyl accident clean-up workers (ACW). Materials and methods. A total of 376 ACW and 123 Kiev city residents with no exposure to radiation participated in the study. Study scope included the case history recording, clinical check-up, electrocardiography (ECG), daily ECG-monitoring, daily arterial blood pressure monitoring, exercise ECG, Doppler ultrasound (Doppler echocardiography), and serum lipid profile assay. The severity of CHD was scored as a sum of functional class (FC) of angina pectoris and stage of heart failure (HF) to estimate the combined impact of several risk factors. Participation in the clean-up work, age, gender, body mass excess, hypercholesterolemia, CHD, diabetes mellitus (DM), survived myocardial infarction (MI) and acute cerebral stroke, heart rhythm abnormalities, and a complete bundle branch block were accounted as risk factors. Both separate and combined impact of those factors was assayed. The combined effect was scored as a sum where value zero corresponded to no sign and value one corresponded to its presence, whereas values from 1 to 4 explained the expression of a sign according to severity or stage of a disease according to contemporary classifications. Results and conclusions. Despite the fact that clinical characterization, functional state of cardiovascular system, and comorbidities in ACW were almost similar to that in control group the onset of CHD in ACW was significantly earlier (55.9 vs. 59.8 years old). According to Spearman's rank-order correlation data there was a reliable link of FC grades and HF severity values sum to the sum of indices scoring the age group of patients, their gender, presence of arterial hypertension, MI in a history, DM type 2, heart rhythm abnormalities, and a complete bundle branch block. Cluster of risk factors

  11. Radiation and non-radiation factors and their impact on the natural history of coronary heart disease in Chornobyl accident clean-up workers.

    PubMed

    Bilyi, D O; Nastina, O M; Gabulavichene, Zh M; Sydorenko, G V; Bazyka, O D; Bilaya, V V; Kovalyov, O S

    2014-09-01

    The objective of the study was to evaluate the impact of a range of risk factors and ionizing radiation on the severity of clinical presentation of coronary heart disease (CHD) in Chornobyl accident clean-up workers (ACW). Materials and methods. A total of 376 ACW and 123 Kiev city residents with no exposure to radiation participated in the study. Study scope included the case history recording, clinical check-up, electrocardiography (ECG), daily ECG-monitoring, daily arterial blood pressure monitoring, exercise ECG, Doppler ultrasound (Doppler echocardiography), and serum lipid profile assay. The severity of CHD was scored as a sum of functional class (FC) of angina pectoris and stage of heart failure (HF) to estimate the combined impact of several risk factors. Participation in the clean-up work, age, gender, body mass excess, hypercholesterolemia, CHD, diabetes mellitus (DM), survived myocardial infarction (MI) and acute cerebral stroke, heart rhythm abnormalities, and a complete bundle branch block were accounted as risk factors. Both separate and combined impact of those factors was assayed. The combined effect was scored as a sum where value zero corresponded to no sign and value one corresponded to its presence, whereas values from 1 to 4 explained the expression of a sign according to severity or stage of a disease according to contemporary classifications. Results and conclusions. Despite the fact that clinical characterization, functional state of cardiovascular system, and comorbidities in ACW were almost similar to that in control group the onset of CHD in ACW was significantly earlier (55.9 vs. 59.8 years old). According to Spearman's rank-order correlation data there was a reliable link of FC grades and HF severity values sum to the sum of indices scoring the age group of patients, their gender, presence of arterial hypertension, MI in a history, DM type 2, heart rhythm abnormalities, and a complete bundle branch block. Cluster of risk factors

  12. A study of the efficacy of radioiodine therapy with individualized dosimetry in Graves' disease: need to retarget the radiation committed dose to the thyroid.

    PubMed

    Schiavo, M; Bagnara, M C; Calamia, I; Bossert, I; Ceresola, E; Massaro, F; Giusti, M; Pilot, A; Pesce, G; Caputo, M; Bagnasco, M

    2011-03-01

    Although Iodine-131 (131I) therapy is fully validated for Graves' disease (GD), there is debate about radioiodine amount to be administered (prescribed activity), as well as the use of individualized dosimetry vs fixed 131I activity. The clinical outcome of 119 GD patients treated with 131I from 2003 to 2008 has been evaluated. The prescribed activity was calculated according to a dosimetric protocol taking into account several variables, including thyroid volume reduction during treatment. In addition, we performed a simulation according to other dosimetric protocols, by calculating the corresponding prescribed activities. The patients were followed up for at least 12 months after treatment. In the first period of observation (2003), a 120-200 Gray (Gy) radiation dose to the thyroid was prescribed, according to the guidelines published by the Italian Societies of Endocrinology, Nuclear Medicine and Medical Physics: hyperthyroidism cure with a single radioiodine administration was obtained in 53% of patients. This outcome raised up to 89% when a higher radiation dose to the target (200- 250 Gy) was prescribed, although the administered activities were still lower, as a rule, than the most commonly employed fixed activities (400-600 Mega-Becquerel--MBq). Our method showed a high level of individual dose optimisation, particularly when compared to simplified methods. In conclusion, the protocol adopted in this study ensures a satisfactory rate of hyperthyroidism cure, while administering quite low 131I activities, provided that an adequate committed radiation dose to the thyroid is prescribed. In this context, the dose indication given by the aforementioned guidelines should probably be revised.

  13. The effects of cosmic particle radiation on pocket mice aboard Apollo XVII: VII. Cosmic ray particle dosimetry and trajectory tracing.

    PubMed

    Cruty, M R; Benton, E V; Turnbill, C E; Philpott, D E

    1975-04-01

    Five pocket mice (Perognathus longimembris) were flown on Apollo XVII, each with a solid-state (plastic) nuclear track detector implanted beneath its scalp. The subscalp detectors were sensitive to HZE cosmic ray particles with a LET larger than or equal to 0.15 million electron volts per micrometer (MeV/mjm). A critical aspect of the dosimetry of the experiment involved tracing individual particle trajectories through each mouse head from particle tracks registered in the individual subscalp detectors, thereby establishing a one-to-one correspondence between a trajectory location in the tissue and the presence or absence of a lesion. The other major aspect was the identification of each registered particle. An average of 16 particles with Z larger than or equal to 6 and 2.2 particles with Z larger than or equal to 20 were found per detector. The track density, 29 tracks/cm2, when adjusted for detection volume, was in agreement with the photographic emulsion data from an area dosimeter located next to the flight package.

  14. Solid-State Personal Dosimetry

    NASA Technical Reports Server (NTRS)

    Wrbanek, John D.; Fralick, Gustave C.; Wrbanek, Susan Y.

    2005-01-01

    This document is a web site page, and a data sheet about Personal protection (i.e., space suits) presented to the Radiation and Micrometeoroid Mitigation Technology Focus Group meeting. The website describes the work of the PI to improve solid state personal radiation dosimetry. The data sheet presents work on the active personal radiation detection system that is to provide real-time local radiation exposure information during EVA. Should undue exposure occur, knowledge of the dynamic intensity conditions during the exposure will allow more precise diagnostic assessment of the potential health risk to the exposed individual.

  15. Neurobehavioral and cognitive performances of children exposed to low-dose radiation in the Chernobyl accident: the Israeli Chernobyl Health Effects Study.

    PubMed

    Bar Joseph, N; Reisfeld, D; Tirosh, E; Silman, Z; Rennert, G

    2004-09-01

    Exposure to low levels of ionizing radiation after the Chernobyl accident in the Ukraine could potentially have influenced the neurobehavioral and cognitive performances of exposed children. A cohort study of adolescents who were children at the time of the accident and who subsequently emigrated to Israel was conducted in 1998-2001. A total of 1,629 children (59% of all 2,769 invited) were included in the study (41% from higher contamination areas, 25% from lower contamination areas, 34% from noncontaminated areas). Mean scores of the Raven Standard Progressive Matrices Test were highest in children in all exposure groups whose parents had a high level of education. No overall relation was found between the cognitive function scores of the child and his/her putative radiation exposure level. Conners' test T scores did not differ significantly by level of exposure. Mothers of all exposure groups who were pregnant at the time of the accident gave their children significantly higher Conners' test scores than did those who were not pregnant. Scores for hyperactivity and attention-deficit/hyperactivity disorder were significantly higher among those who were in utero at the time of the accident. These results do not show differences of neurobehavioral or cognitive performance in exposed versus nonexposed children. There is a possible behavioral effect among offspring of pregnant mothers or mothers of very young children in all exposure levels.

  16. SU-C-12A-04: Diagnostic Imaging Research Using Decedents as a Proxy for the Living: Are Radiation Dosimetry and Tissue Property Measurements Affected by Post-Mortem Changes?

    SciTech Connect

    Sandoval, D; Heintz, P; Weber, W; Melo, D; Adolphi, N; Hatch, P

    2014-06-01

    Purpose: Radiation dose (RD) from diagnostic imaging is a growing public health concern. Implanting dosimeters is a more accurate way to assess organ dose, relative to commonly used mathematical estimations. However, performing accurate dosimetry using live subjects is hindered by patient motion and safety considerations, which limit the RD and placement of implanted dosimeters. Performing multiple scans on the same subject would be the ideal way to assess the impact of dose reduction on image quality; however, performing multiple non-standard-of-care scans on live subjects for dosimetry and image quality measurements is generally prohibited by IRB committees. Our objective is to assess whether RD and tissue property (TP) measurements in post-mortem (PM) subjects are sufficiently similar to those in live subjects to justify the use of deceased subjects in future dosimetry and image quality studies. Methods: 4 MOSFET radiation dosimeters were placed enterically in each subject (2 sedated Rhesus Macaques) to measure the RD at 4 levels (carina, lung, heart, and liver) during CT scanning. The CT protocol was performed ante-mortem (AM) and 2 and 3 hours PM. For TP analysis, additional scans were taken at 24 hours PM. To compare AM and PM TP, regions-of-interest were drawn on selected organs and the average CT density with standard deviation (in units of HU) were taken; additionally, visual comparisons of images were made at each PM interval. Results: No significant difference was observed in 8 of 9 measurements comparing AM and PM RD. Only one measurement (liver of the first subject) showed a significant difference (7% lower on PM measurement), possibly due to subject re-positioning. Initial TP visual and quantitative analyses show little to no change PM. Conclusion: Our results suggest that realistic radiation dosimetry and image quality measurements based on tissue properties can be performed reliably on recently deceased subjects.

  17. Neutron personnel dosimetry intecomparison studies

    SciTech Connect

    Sims, C.S.

    1991-01-01

    The Dosimetry Applications Research (DOSAR) Group at the Oak Ridge National Laboratory (ORNL) has conducted sixteen Neutron Personnel Dosimetry Intercomparison Studies (PDIS) since 1974. During these studies dosimeters are mailed to DOSAR, exposed to low-level (typically in the 0.3 -- 5.0 mSv range) neutron dose equivalents in a variety of mixed neutron-gamma radiation fields, and then returned to the participants for evaluation. The Health Physics Research Reactor (HPRR) was used as the primary radiation source in PDIS 1--12 and radioisotopic neutron sources at DOSAR's Radiation Calibration Laboratory (RADCAL) were mainly used, along with sources and accelerators at cooperating institutions, in PDIS 13--16. Conclusions based on 13,560 measurements made by 146 different participating organizations (102 - US) are presented.

  18. Criteria for personal dosimetry in mixed radiation fields in space. [analyzing trapped protons, tissue disintegration stars, and neutrons

    NASA Technical Reports Server (NTRS)

    Schaefer, H. J.

    1974-01-01

    The complexity of direct reading and passive dosimeters for monitoring radiation is studied to strike the right balance of compromise to simplify the monitoring procedure. Trapped protons, tissue disintegration stars, and neutrons are analyzed.

  19. Methods to Estimate Solar Radiation Dosimetry in Coral Reefs Using Remote Sensed, Modeled, and in Situ Data.

    EPA Science Inventory

    Solar irradiance has been increasingly recognized as an important determinant of bleaching in coral reefs, but measurements of solar radiation exposure within coral reefs have been relatively limited. Solar irradiance and diffuse down welling attenuation coefficients (Kd, m-1) we...

  20. Establishment of ANSI N13.11 X-ray radiation fields for personal dosimetry performance test by computation and experiment.

    PubMed Central

    Kim, J L; Kim, B H; Chang, S Y; Lee, J K

    1997-01-01

    This paper describes establishment by computational and experimental methods of the American National Standard Institute (ANSI) N13.11 X-ray radiation fields by the Korea Atomic Energy Research Institute (KAERI). These fields were used in the standard irradiations of various personal dosimeters for the personal dosimetry performance test program performed by the Ministry of Science and Technology of Korea in the autumn of 1995. Theoretical X-ray spectra produced from two KAERI X-ray generators were estimated using a modified Kramers' theory with target attenuation and backscatter correction and their spectral distributions experimentally measured by a high-purity germanium semiconductor detector through proper corrections for measured pulse height distributions with photopeak efficiency, Compton fraction, and K-escape fraction. The average energies and conversion coefficients obtained from the computation and experimental methods, when compared with ANSI N13.11 and the recently published National Institute of Standards and Technology X-ray beams, appeared to be in good agreement--(+/-)3% between corresponding values--and thus, could be satisfactorily applied in the performance test of personal dosimeters. PMID:9467054