The 54th Annual Meeting of the Health Physics Society
July 12-16, 2009
Minneapolis, MN

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.   Be a 21st Century PowerPoint Creator – Designing High-Impact Presentations for a Digital Generation J Krampert*, Merck & Co., Inc. ; A Cook, Merck & Co., Inc.; V Williams, Merck & Co., Inc.

Abstract: Do people tell you your presentations are boring? Do you get more yawns then applause? Do you wish you could pull your presentations into the 21st Century? Well, we did, we decided to do something about it, and you can too. In this presentation, we will discuss our encounters with presenting uninspiring presentations and our exploration of new methods of creating engaging, multimedia experiences. We will review some of the technologies available that helped us improve our presentations, the various skills needed to implement our ideas, and in some cases, optional methods that may be less expensive or more user-friendly that will produce the same improved presentations. Finally, we will discuss the results we achieved when incorporating our ideas into our current training presentations and we will show you that you too can create high-impact presentations with minimal work and expense.

.   Neutron Dosimetry by Activation Technique MUFTAH ZEELK ; MOHAMED ALSHOKAKH

Abstract: The absolute and relative measurements of neutron intensities can be precisely determined by activating a foil in the neutron field and counting its radioactivity . In this work, the neutron flux was determine by using indium foil near a Pu-Be source with yield of about 5.5 106 n/s. The 54 minute activity of indium is frequently used for the determination of low fluxes. The cross section does not follow the I/v-law. Because of the resonance in the erring which can lead to strong epithermal activity of the indium foil and also perturbing 4.5 hr, activity is produced by an isomer of indium that can be excited by inelastic scattering of fast neutrons. Activations of indium foil-115 with mass 0.104 g and thickness of cadmium cover was 1mm . The 115 ln(ç,ã) reaction was used to measure the â-decay when G.M. counter used the indium foil was irradiated twice firstly without the cadmium plate and then with cadmium plate (for the same distance from the source), the irradiation was repeated with both side of the indium foil covered with the cadmium plate of 1mm thickness, then measurement of the foil activity both thermal and epithermal neutrons also the activity irradiation with only epithermal neutron. A scintillation detector with a Nal(Ti) crystal 3 in by 3in. with a good resolution manufactured by Harshow was used, the spectrometric measurement of induced gamma rays of 1.3 Mev energy were performed> The induced activity of indium foil was determined by the absolute method and taking in to consideration the experimental geometry efficiency of the scintillation detector, abundance of measured gamma rays and isotopic composition of the indium. The results of thermal flux obtained were compared with estimated neutron flux distribution from the numerical solution of one-dimensional Boltzman transport equation using ANISN code that was prepared by Dydejczyk (1991) . The results of thermal neutron flux conducted show that good agreement was achieved between the especial distribution of the experimentally determined thermal neutron flux and theoretically estimated flux. The best agreement was obtained for activation of indium foil using Nal(Ti) counter. The difference between the values of the neutron flux is probably due to the absolute measurement of the foil activity, especially when G.M. counter was used The ratio of öth/öepi is relatively higher which indicates high concentration of hydrogen in the vicinity of the neutron source and becomes higher with an the distance from the source. For every measurement, the relative average error for the indium foil measured using G.M. counter 47% and in the case of Nal(Ti) was use a about 10%. On the basis of 10 measurements of the thermal neutron flux of the chosen position (distance (d)=5.75cm) an approximation of the standard deviation of individual thermal neutron flux and the 95% confidence interval were determined using student's test. It was also calculated that the standard deviation of the estimated individual thermal neutron flux was ó=60 n/cm2s and at 95% confidence interval was ∆95%=133 n/cm2sec. The relative error (precision) was approximated based on the confidence interval and was about 1% in this case.

.   Evolution of Osteoporosis by Dual Energy X-Ray Absorptiometry (DXA): Effect of Age, Sex and Menopause state in women Rajamaickam Karunanithi*, K. J. Research Foundation ; Singaravelu Ganesan, Anna University; Thazhe Mangool Rama Panicker, K. J. Research Foundation; M Paul Korath, K. J. Research Foundation; Kesav Jagadeesan, K. J. Research Foundation

Abstract: ABSTRACT Bone Mineral Density (BMD) is routinely assessed by Dual Energy X-ray Absorptiometry (DXA) which is considered as 'gold standard' tool as per World Health Organization (WHO-1994). The technique is attractive because it is non-invasive, is easily applied for both healthy individuals and patients, and the radiation dose is extremely small. Two hundred men and two hundred women whose age ranged from 35 to 73 in women and 35 to 79 in men were studied. BMD of the right proximal femur was evaluated using Hologic QDR-4500 bone densitometer. Five regions of interest viz., femoral neck, trochanter, inter-trochanter, total-hip and Ward's triangle regions were assessed (the usual procedure in the DXA assessment adopted). A follow-up after six months was carried out to determine the changes in BMD for 25 women and 25 men. Results: BMD in men is higher than women in all age groups. In women, the ailing effect of surgical menopause on BMD was similar to natural menopause and hence removal of ovaries at early age may lead to increased fracture risk. The follow-up results show a significant (P=0.008)reduction in BMD in women and (p = 0.029) reduction in men. This findings confirms that rate of BMD depletion is higher in women than in men. Key words: DXA, Bone Mineral Density, Osteoporosis

.   A Radiation Physicist’s Recollection of 40 Years at SLAC W. R. Nelson*, SLAC National Accelerator Laboratory

Abstract: The late W. K. H. Panofsky, the first Director of SLAC, was a strong advocate of Accelerator Health Physics and more than once he said: “…those charged with accelerator radiation protection should consider themselves scientific and technical professionals first and enforcers of compliance with established processes second”*. “Pief”, as he was better known to all of us, was so committed to this belief that he placed the Health Physics Department within the Research Division at SLAC and made scientific research part of our job description. He recognized from the very beginning that radiation protection had to be at the top of the priority list for the laboratory, but he also wanted to make sure that the work was done by people who really knew what they were doing. This Morgan Lecture describes, in an anecdotal fashion, how this philosophy encouraged the author, and other health physicists, to participate directly in a variety of engineering and physics activities at SLAC, and how this contributed to the development of new technologies, and even new physics, by these participants. * A History of Accelerator Radiation Protection, H. Wade Patterson and Ralph H. Thomas, Editors (Nuclear Technology Publishing, England, 1994).

.   Evaluation of Shield Thicknesses for PET/CT Facilities Sajid Ali*, Pakistan Nuclear Regulatory Authority ; Mehboob Ali, Pakistan Nuclear Regulatory Authority; Muhammad Shahid, Pakistan Nuclear Regulatory Authority; Tariq Saddique, Pakistan Instiute of Engineering and Applied Sciences

Abstract: The objective of this task was to investigate the methods of calculating the shield thicknesses of PET/CT facilities. The ultimate goal was to evaluate the shield thicknesses of PET/CT facilities in Shaukat Khanum Memorial Cancer Hospital (SKMCH) and Institute of Nuclear Medicine and Oncology (INMOL) in Lahore, Pakistan. Shielding calculations for PET/CT facilities are based on two reports; first report is TG-108, and the second report is NCRP-147. Proposed shield thicknesses were compared with the calculated shield thicknesses. It is concluded that, using the proposed shield thicknesses from the above references, some rooms required additional shielding whereas other rooms are over shielded as in the case of a PET/CT suite. The proposed shield of a cyclotron vault is similar with calculated shield and measured dose rate profiles through the shield that satisfies the regulatory dose limits.

.   A Method for Optimizing the Performance of an Alpha 7 Continuous Air Monitoring System DL Wannigman*, Los Alamos National Lab ; KP Thompson, Los Alamos National Lab

Abstract: A continuous air monitoring (CAM) system employing 200 ThermoFisher Scientific Alpha 7L CAMs has been in use in the Plutonium Facility at Los Alamos National Laboratory (LANL) for three years. During this time, the performance of these instruments has not been optimal due to the convoluted and obscure relationship between the CAM operational settings and the resulting minimum detectable levels, alarm set points, and alarm response times. To further complicate matters, the Alpha 7 logs its operational data in Microsoft® Access files which don't readily lend themselves to complex data analyses. A method has been developed that extracts and processes data from a system of CAMs to generate performance trending information. This program runs as an adjunct to Microsoft® Excel, and it can be easily tailored to a specific monitoring application. After applying this automation tool to improve the function of their CAMs, LANL now has a 3 DAC-h CAM system with a false alarm rate of less than 0.02 false alarms per CAM per year. Test data will be presented that shows that these optimized CAMs should reliably alarm to an 8 DAC-h release in less than 90 seconds.

.   A Novel Method to Pinpoint Beam Losses M.L. Marceau-Day*, Louisiana State University ; R.E. Teague, Louisiana State University; W.-H. Wang, Louisiana State University

Abstract: Following a shutdown at the Center for Advanced Microstructures and Devices, a synchrotron research facility, of Louisiana State University, elevated radiation levels were observed after the wiggler was removed. Although the beam position monitors indicated that the beam was in the correct position, this finding persisted and was characterized by a strong forward directed peak with a cone-shape pattern that was produced by the beam interacting with the beam pipe that was subsequently identified. In order to investigate this elevated radiation level, an easy and effective method using the ordinary photographic film was developed. Several rolls of commercially available ISO 400 film (35 mm with 24 exposures) were purchased. The ISO 400 film is considered a faster film with larger silver halide grain sizes as compared with ISO 100 film which contains a layer of finer silver halide crystals. Both types of film were utilized in this project and worked equally well. Film was removed from the canisters. The length of the ISO 400 film was approximately 114.3 cm (45 inches). The ISO 100 film was cut to desirable length, as needed. Four rolls of ISO 400 film were joined together, alternating the natural curl of the film to make a relatively straight piece of film assembly (45 inches) marked as a ruler with one-half inch increments. This film ¡§ruler¡¨ was then placed over the suspected area of the high-energy electron beam loss. The ISO 100 film was arranged in the same manner. In addition, Canberra Dosicards were hung adjacent to the area to obtain a real time readings during operations. Once the accelerator was turned off, the readings on the Dosicards were recorded and the film was collected. The exposed film was laid on a flat table and a Ludlum Model 3 survey meter with a pancake probe was used to scan the exposed film. When a section of film was found to be radioactive, it indicated that the silver in the silver halide grain had been activated from Ag-107 to Ag-108 (T 1/2 = 2.39 min). A pinhole of 0.25 cm diameter was cut into a 0.16 cm thick of a lead plate. With the lead shield between the pancake probe and the exposed film, it was possible to resolve the highest radiation reading on the film. The film was then placed back in its original exposure position. The location of the hot spot was marked on the exterior surface of the beam pipe, indicating the point of the electron beam interacting with the beam pipe. Even though the beam position monitors upstream and downstream of the beam interaction point continued to suggest that the beam was in the correct position, the measurements prompted a re-evaluation of the vertical position of the beam pipe. It was found that the beam pipe was 0.635 cm too low. Thus the beam was lost when hitting the upper portion of the beam pipe. The beam pipe was re-aligned and additional shielding was put into place. The radiation dose equivalent in the concerned area fell from 72 milliSv to 38 microSv. This proposed method to determine the location of the beam losses proved to be an effective approach with easy and rapid measurements and significantly low operational cost.

.   Development of Direction Finding Detector for Remote Sensing of Radiation Leakage from Nuclear Facilities Yusuke Kobayashi, ALOKA CO.,LTD ; Toshiya Yamano, ALOKA CO.,LTD; Yoshiyuki Shirakawa*, NIRS

Abstract: A monitoring station is continuously working for the environmental radiation measurement around a nuclear facility in Japan. Measured dose rate can be sometimes higher than the usual values because of rainfall , and so on. In this case, it is necessary to judge whether the radiation leakage has occurred in the nuclear facility or not. The effective method is to know the direction of incident radiation. We have developed direction-finding detectors to know the incident direction of gamma-ray. The detector is constructed of three pieces of NaI(Tl) scintillators. The principle and performance have been examined by both computer simulations and laboratory experiments. The results show that the detector can measure incident direction of gamma-ray and keep the direction error within 3 degrees. We also confirm the developed measurement device can apply to Japanese Industrial Standard (JIS Z 4325 Equipment for continuously monitoring gamma radiation in the environment) In the near future, we will use more than two detectors and will be able to obtain the information of source location with the incident direction. Moreover, we think the detector will be useful for homeland security.

.   Hematology Physicians Preparing for a Mass Casualty Marrow Toxic Incident Cullen Case Jr.*, NMDP ; Dennis Confer, NMDP; Nelson Chao, Duke University; Daniel Weisdorf, Univ. of MN; David Weinstock, Harvard; Robert Krawisz, ASBMT

Abstract: The NMDP in partnership with the American Society for Blood and Marrow Transplantation (ASBMT) provides leadership for the Radiation Injury Treatment Network® (RITN) (www.RITN.net), which consists of 56 bone marrow transplant centers, bone marrow donor centers and cord blood banks that are preparing to treat victims of a marrow toxic mass casualty incident (such as injuries received from exposure to ionizing radiation or mustard gas). If marrow toxic injuries are sustained, all victims would require specialized intensive medical care and many of the victims would need to identify an unrelated marrow or cord blood match on the National Marrow Donor Program's Registry. Since RITN's formal inception in 2005 it has conducted annual tabletop exercises, developed plans for responding to a marrow toxic incident and educated over 1700 medical professionals about their role in responding to a mass casualty incident resulting in victims with marrow toxic injuries. It is important to educate hematology and oncology professionals about their role in a marrow toxic mass casualty incident because marrow toxic injuries are a unique medical scenario where the patients require specialized intensive medical care. Marrow toxic incidents include exposure to ionizing radiation and mustard gas; victims exposed to these hazards may develop Acute Radiation Syndrome (ARS) a type of marrow toxic injury, or symptoms that mimic ARS, both require intensive supportive care from hematology or oncology medical specialists whom have expertise in its treatment.

.   Implications of Granite Counter Top Construction and Uses David Bernhardt*, Consultant ; Al Gerhart, Solid Surface Alliance; Linda Kincaid, Industrial Hygiene Services

Abstract: Granite is a term for natural stones such as pegmatites, migmatites, gneisses, and schists used for residential countertops, and other indoor trim. Some granites are anatectic alaskites similar to the Rossing uranium deposits. Uranium and thorium concentrations range from those similar to normal soil (roughly 0.04 Bq/g, 1 pCi/g) to over 15 Bq/g of uranium; with lower concentrations of thorium. Regulations in the European Community and Canada exclude elevated stone from these markets. In the U.S. radiation screening limits by some companies (0.2 to 0.3 ìGy/hr) and the supply have resulted in limiting the installations of elevated stone to a fraction of the total market being installed in homes, but elevated slabs are still installed. The primary health risk to workers is due to airborne dust, from sawing and milling granite slabs which contain free silica, heavy metals, and uranium and thorium. Depending on work-place controls, the primary risk may be silicosis, but there are also potential risks from other toxin materials (e.g., beryllium) and radiation exposure. Potential health risks to consumers using granite are primarily due to the increased concentration of indoor radon and external gamma dose from the uranium and thorium in the granite. The presentation will provide assessments for workers and estimates of the elevated indoor radon and gamma dose for consumers. Assessments using controlled chambers, modeling, and indoor measurements indicate that some granite slabs similar to the screening levels can increase the indoor 222Rn concentration by about 40 Bq/m3 (1 pCi/l), with higher concentrations for more elevated slabs. Granite counter tops with elevated gamma exposure rates of about 1 ìGy/hr result in potential gamma doses that are a significant fraction of 1mSv/yr, a basic criterion for the general population.

.   Progress In Development Of A Software Tool For Rapid Direct Radiation Gamma Dose Assessments For Complex Source/receptor Geometries Oleg Povetko*, Southwest Research Institute, San Antonio, TX ; Alexei Kouznetsov, Tom Baker Cancer Center, Calgary, Canada; Slava Golikov, Institute of Radiation Hygiene, St. Petersburg, Russia; Roland Benke, Southwest Research Institute, San Antonio, TX

Abstract: The purpose of this study is to develop (i) a software prototype for direct radiation dose assessment that combines the advantages of deterministic and stochastic methods and (ii) a user-friendly interface that will allow this method to be widely used in health physics, environmental, medical, and educational applications. The hybrid approach combines recent advances in three-dimensional object representation methods and a novel chord distribution approach to accelerate the computation of dose inside the receptor body for complex radiation source and receptor geometries. Several generations of emitted, scattered, and newly born particles are modeled to develop secondary sources. The method then uses stochastic simulation of the photon interaction data on the chord distribution to compute absorbed radiation dose. This project demonstrates a computational method faster than pure stochastic methods and sufficiently accurate for a wide class of applications. This hybrid approach was incorporated into prototype software, which was copyrighted under the name RADCOG® developed on the Microsoft® Visual Studio® platform. The software implements a multilevel hierarchy of nested three dimensional elements. The user-friendly framework interface allows the user to develop or import various three-dimensional objects generated by external graphic editors in commonly used digital formats. The user may specify radiation source characteristics by either arbitrary space-energy-angular distributions or concentrations of built-in isotopes. The receptor absorbed dose is calculated for the complex object assembled on the screen. The software was validated for gamma-ray radiation fields. The calculated numerical dose values agree well with the results calculated by an industry-standard Monte Carlo N-Particle (MCNP) code and with literature data based on the results of several different stochastic codes for receptors of simple and complex geometries irradiated by internal and external sources emitting gamma rays between 20 Kev and 10 Mev. The RADCOG® software calculated doses 2 – 50 times faster than MCNP code with comparable statistical errors. Furthermore, the computational time gains increase with increasing complexity of the geometry. * The abstract is based on work funded by Southwest Research Institute®.

.   Photon and Neutron Iso-dose Contours for LINACs Siraj Khan*, DHS ; Sami Sherbini, NRC

Abstract: It is necessary to map the photon and neutron radiation fields around the electron LINACs, which were originally developed for the radiation therapy applications but which are now beginning to see applications in the non-intrusive inspection (NII) technology for the screening of cargo and vehicles in homeland security and force protection. This paper presents results of MCNPX simulations of photon and neutron iso-dose contours around 10-to-20 MV LINACs so that this data can be used to determine the radiation safety exclusion zones for the protection of workers and members of the general public. Results of the radiation dose to undocumented aliens (stowaways) in the vehicles will also be presented.

.   Elemental Bio-imaging of Actinides and Beryllium in Lymph Nodes of Former Nuclear Workers S.Y. Tolmachev*, United States Transuranium and Uranium Registries, Richland ; D. Bishop, University of Technology, Sydney; P. Doble, University of Technology, Sydney; D. Hare, University of Technology, Sydney; A.C. James, United States Transuranium and Uranium Registries, Richland

Abstract: This study explored the application of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to elemental bio-imaging (EBI) of actinides [thorium (Th), uranium (U), plutonium (Pu), and americium (Am)] and beryllium (Be) in samples of human tissue. The tissue samples were from occupationally exposed ‘nuclear weapons site’ workers, who had voluntarily donated their tissues to the U.S. Transuranium and Uranium Registries (USTUR). This EBI technique provides two-dimensional mapping of the concentration of elements in the surface layer of a sectioned tissue (by isotopic number). For this exploratory study, single sections of thoracic (respiratory tract) lymph nodes from five individual workers were mapped for actinide isotopes and 9Be. In all cases where the isotopic distribution was detectable, this was highly localized, suggesting that the materials were still present (many years after intake) as discrete particles, and not ‘leached’ by dissolution and subsequently chemically diffused throughout the tissue. In all cases, whether or not they were exposed occupationally to U, the concentration distribution of 238U was measurable. In the case with occupational exposure to uranium, the concentration distribution of 235U was measurable. None of the cases were occupationally exposed to Th, yet the concentration distribution of background 232Th was measurable in all cases. The distribution of 9Be was measurable in only one of the three cases with ‘self-reported’ exposure to Be. Neither 239Pu nor 241Am was detectable in the thoracic lymph node from a case whose Pu exposure had been by skin wound. Also as expected, based on the limit of detection for actinides using quadrupole ICP-MS, the concentration distributions of 239Pu and 241Am were not measurable in the thoracic lymph node from a case exposed by inhalation to insoluble Pu. In this case, the mass concentrations estimated from external low background gamma-spectrometry were 65 pg/g (0.15 Bq/g) and 3.3 pg/g (0.42 Bq/g), respectively. In all cases, the concentration distribution of the major elements (Ca, P, Mg and Si) were measured. All of these distributions were non-uniform, i.e., they exhibited the characteristics of localized ‘foreign’ materials. The implications of these findings for dose assessment and industrial hygiene are discussed.

.   The Differences of the Reaction of Hematopoiesis and Bone Tissue Among People with Incorporated Osteotropic Isotope 90Sr A. Akleyev, Urals Research Center for Radiation Medicine, Chelyabinsk, Russia ; G. Dimov*, Urals Research Center for Radiation Medicine, Chelyabinsk, Russia; I. Akushevich, Center for Population Health and Aging, Duke University, Durham, NC, USA; G. Veremeyeva, Urals Research Center for Radiation Medicine, Chelyabinsk, Russia; T. Varfolomeyeva, Urals Research Center for Radiation Medicine, Chelyabinsk, Russia; V. Ivanov, Urals Research Center for Radiation Medicine, Chelyabinsk, Russia; S. Ukraintseva, Center for Population Health and Aging, Duke University, Durham, NC, USA; A. Yashin , Center for Population Health and Aging, Duke University, Durham, NC, USA

Abstract: The population of the Techa riverside villages has been chronically exposed to radiation in a wide range of doses as a result of releases of radioactive waste into the river. About 87% of accumulated bone surface dose of internal irradiation was contributed by 90Sr. The target tissue for this long-living nuclide is red bone marrow (mean cumulative red bone marrow dose at 1956 was 333.6±4.6 mGy, at 2005 – 493.9 ±0.01 mGy) and the layer of osteogenic cells (mean cumulative bone surface dose at 2005 was 1470±0.04 mGy). The analysis of about 3,200 hemograms for inhabitants of the Techa Riverside villages measured over years (1951-1956) of chronic exposure to ionizing radiation with gradual decrease of dose rate showed a gradual increase in frequency of cytopenias with increasing the dose rate value. Over the years 4 to 8 after the onset of radiation exposure some clinical and morphological changes in bone tissues of primarily dystrophic character were noted among individuals with the highest doses to the bone tissue up to 2000 mGy and higher with significantly increased frequency (Akleyev and Kisselyov 2002). In the late period after the start of chronic radiation exposure (50 years later) the incidence of neutropenia, lymphopenia and thrombocytopenia did not exceed that seen in the control group. The elevation of degenerative and dystrophic alterations in bones and joints was observed in the later period after 90Sr intake. About a half of people with 90Sr incorporation and control group have changes in bone tissue expressed by different stages of osteoporosis. The age is a determinative factor of bone tissue involution in women while some tendency of 90Sr influence on the intensity of osteoporosis is revealed in male group. The differences of the reaction of hematopoiesis and bone tissue on chronic radiation exposure due to incorporated 90Sr are determined by the type of cell kinetics in these tissues.

.   Modeling of Photon Trajectories in Absorbers to Augment Undergraduate Laboratory Instruction Philip Fulmer*, Francis Marion University, Florence SC

Abstract: Senior undergraduate health physics students at Francis Marion University take a course in nuclear radiation physics, where the interactions of charged particles, photons, and neutrons are examined in depth. As part of this class, students are instructed in the use of Monte Carlo techniques, particularly as they are applied to photon interactions. In the laboratory session for this class, students modify and use a Monte Carlo program written in Visual Basic as part of Microsoft Excel. This program has been discussed previously in its ability to simulate elementary photon interactions while allowing students to understand the foundational principles for the preparation of a Monte Carlo program. In its newest incarnation, students assisted in modifying the program to show the trajectories of photons within an absorber. This allows the students to see the simulated path of photons within the absorber. Because of the difference in the interaction coefficients depending on material type, it is instructional for students to see the projected photon paths in different absorbers as a function of material type and photon energy. This experience helps students to understand the photon interactions more completely. Insepction of trajectories helps students see under what conditions the photoelectric effect is dominant; in addition, the scatter angles of photons that undergo the Compton effect can be seen visually and explained on the basis of the Klein-Nishina cross section. This work presents the results of various simulations for a variety of absorbers and photon energies along with the source code for the program so that others can benefit from a visual representation of the photon trajectories following interactions in various materials.

.   Proliferation, cell cycle and apoptosis in blood lymphocytes at late time after chronic radiation exposure in man Tatyana Pochukhailova* ; Evgenia Blinova; Aleksandr Akleyev

Abstract: The aim of the study was to assess proliferative activity, cell cycle delays and the level of apoptosis in peripheral blood lymphocytes among chronically exposed subjects with long-term leucopenia. For residents of localities contaminated with radionuclides in Chelyabinsk oblast, the hemopoietic system represents a critical link due to a high radiosensitivity of the red bone marrow and bone-seeking properties of 90Sr. A long-term exposure to low-dose rate radiation resulted in reduced counts of mature peripheral blood cells (leucopenia, thrombocytopenia), both in the early and the late period of exposure. Assessment of proliferative activity of peripheral blood lymphocytes was conducted based on contents of ki-67 protein, that of delays in cell cycle was based on contents of Chk2 protein using flow-cytometry. The level of apoptotic cells was measured using the TUNEL technique. Exposed individuals with leucopenia manifested an increase in the baseline levels of lymphocytes with a delayed cell cycle, apoptotic cells and proliferating cells in the peripheral blood. Following stimulation of cells to division, subjects with leucopenia demonstrated a lower rate of dividing cells as compared to that seen in unexposed subjects. Increased percentage of apoptotic cells under additional external exposures (incubation, in vitro irradiation) can only be observed on comparing exposed individuals with leucopenia to exposed individuals without leucopenia. It can be suggested that the results of this study are indicative of changes in radiosensitivity of peripheral blood lymphocytes which may be associated in subjects with leucopenia with long-term low-dose rate radiation exposure.

.   Influence of polarized radiofrequency electromagnetic fields on stem hemopoietic cells in mice Natalia Dukhovnaya*, Urals Research Center of Radiation Medicine, Chelyabinsk, Russia ; Galina Tryapitsyna, Urals Research Center of Radiation Medicine, Chelyabinsk, Russia; Vladimir Polevik, Urals Research Center of Radiation Medicine, Chelyabinsk, Russia; Aleksandr Akleev, Urals Research Center of Radiation Medicine, Chelyabinsk, Russia; Evgeny Pryakhin, Urals Research Center of Radiation Medicine, Chelyabinsk, Russia

Abstract: At the present time engineering development has led to essential electromagnetic environmental contamination. There are not enough data to completely resolve a problem of danger of such influence on human health. In our experiments we estimated influence of electromagnetic radiation of various polarization on hematopoietic system in mice using a method of endogenous colony-formation in a spleen. Following schemes of exposure were used: once or daily within 3 days animals were exposed to radiofrequency electromagnetic field (RF-EMF) (600 seconds exposition, EMF carrier frequency 925 MHz, frequency modulation 217 Hz; 1.2 mW/cm2 - that corresponds to a maximum permissible power exposition (200 ìW*h/cm2) accepted in Russia for RF-EMF). Through 5h after EMF influence animals were exposed to the external total ã-irradiation (6 Gy, dose rate 0.7 Gy/min). At 9th day quantity of colony-forming units in a spleen (CFU-S), quantity of nuclear cells in bone marrow were defined. After one-time irradiation, as well as after 3 days of exposition in all experimental groups average CFU-S quantity was less than in control group. Effects of RF-EMF with right polarization were the most expressed. Quantity changes of CFU-S in group of animals subjected to influence of RF-EMF with left polarization were less expressed, the effects of RF-EMF with linear polarization were intermediate. It is possible to explain observable effects through functional changes of stem hemopoietic cells such as decrease stem cells pool because of their proliferation and transit to pool of committed progenitor cells. Then, spatial polarization of radiofrequency electromagnetic radiation may lead to modification of the biological effects.

.   Key Findings of CDC’s Los Alamos Historical Document Retrieval and Assessment Project– Public Exposures from the Trinity Test T.E. Widner*, ChemRisk LLC ; S.M. Flack, ChemRisk LLC; R.E. Burns, Jr., NGTS, Inc; J.J. Shonka, Shonka Research Associates; J.E. Buddenbaum, ENSR/AECOM

Abstract: Because of the complexity of the implosion-assembled bomb developed at Los Alamos, a test was considered necessary. The Trinity test conducted near Socorro, NM on 16 July 1945 fell within the scope of the Los Alamos Historical Document Retrieval and Assessment (LAHDRA) project led by the Centers for Disease Control and Prevention (CDC). To preserve the secrecy of the atomic bomb mission and avoid claims against the Army, residents of New Mexico were not warned before the blast or informed of residual health hazards afterward, and no residents were evacuated. The device was detonated close to the ground, causing much soil to be drawn into the fireball and form radioactive fallout. Exposure rates measured up to 15 or 20 R/h in public areas about 20 mi northeast of ground zero. Field teams used instruments that were crude, ill suited to field use, and incapable of measuring about 4.8 kg of unfissioned plutonium that was dispersed. Vehicle shielding and contamination were not corrected for. Terrain and air flow patterns caused “hot spots” in and around what became known as “Hot Canyon” and on Chupadera Mesa. Key residential areas were unknown to monitoring teams and were not visited on test day. Ranchers reported that fallout “snowed down” for 4-5 d after the blast. Many residents collected rain water off their metal roofs into cisterns for drinking. It rained the night of test day, so fresh fallout was likely consumed. Most ranches had one or more dairy cows and a ranch near Hot Canyon maintained a herd of 200 goats. All evaluations of public exposures from Trinity published to date have been incomplete in that they have not reflected the internal doses that were received by residents from intakes of airborne radioactivity and contaminated water and foods. Too much remains undetermined about exposures from the Trinity test to put the event in perspective as a source of public radiation exposure or to defensibly address the extent to which people were harmed.

.   Key Findings of CDC’s Los Alamos Historical Document Retrieval and Assessment Project– Potential Public Exposures from Early Airborne Plutonium Releases T.E. Widner, ChemRisk, LLC ; J.J. Shonka*, Shonka Research Associates; R.E. Burns, Jr., NGTS. Inc.; J.E. Buddenbaum, ENSR/AECOM

Abstract: Under the Los Alamos Historical Document Retrieval and Assessment (LAHDRA) project led by the Centers for Disease Control and Prevention (CDC), airborne plutonium releases were prioritized based on historical release totals for DP West Site’s Building 12 stacks published by Los Alamos National Laboratory (LANL) in the 1970s. Values for 1948-55 were adjusted upward by the LAHDRA team (by roughly a factor of 20) based on a study conducted by Lab industrial hygienists in 1955-56. In that study, stack releases were measured with improved, isokinetic stack sampling systems that were operated alongside the original systems. Correction factors were determined and applied to releases previously reported for 1948-55. All values from 1948-75 were adjusted further by the LAHDRA team using sample line loss and filter burial correction factors based on assessments performed by LANL staff. No effluent data were located for the wartime processing of plutonium in D Building, and LANL’s release estimates include no contribution from D Building during its 10 y of operations or from DP West Site plutonium processing 1945–47. If plutonium releases from the Building 12 stacks 1948-55 were as high as the 1956 documents indicate, LANL’s releases could easily have exceeded independently reconstructed airborne plutonium release totals from the production plants at Hanford, Rocky Flats, and Savannah River combined, even without the other sources and other years at LANL included. Residential areas were built closer to production areas at LANL than at any other major Manhattan Project, AEC, or DOE site. A screening assessment using the methodology of National Council on Radiation Protection and Measurements (NCRP) Report No. 123 was performed for releases from DP West Site Building 12 stacks during 1949, the apparent year of peak emissions. Through screening at Levels I, II, and III, results indicate that public exposures from airborne plutonium releases warrant further evaluation.

.   Characterizing a New Technology for External Personnel Dosimetry J Wright, Dosimetry & Imaging PTY ; A Ujhazy, Dosimetry & Imaging PTY; H Riesen, Univ of New South Wales; B Dicey*, Dosimetry Resources International

Abstract: This study evaluates the response to radiation of the “Optically Excited Luminescent” OEL compound Barium Chlorofluoride doped with Samarium, (BaFCl:Sm). An advanced reader was developed by A/Prof H Riesen, University of New South Wales. BaFCl:Sm was tested at several facilities in Australia using ARPANSA calibrated sources, providing calibrated data for 137Cs, X-Rays, 99mTc and 6/18MV photons, demonstrating high sensitivity from 60kVp to 18MV. Further testing is underway to characterize response to other radiations. BaFCl:Sm is sensitive to very low levels of radiation - 60 nGy (X-ray) and 15µGy (662 keV). Energy-independent linear response is observed from 10uGy (70kVp) to 10Gy (6MV). There is extremely low loss of signal through repeated reads. BaFCl:Sm has application in patient dose monitoring, homeland security and occupational dosimetry.. The system meets key test criteria: 1. Wide energy range. 2. Dose rate independent 3. Very low signal loss. 4. Superior sensitivity. 5. Stable & repeatable chemistry.

.   Radioactivity and Radiation: Atlanta Chapter's educational material and experience with the Georgia Science Teacher Association M. C. Nichols*, Georigia Power ; J.J. Shonka, Shonka Research Associates; D.J. Collins, U.S. Nuclear Regulatory Commission; D. K. Philpotts, Georgia Power; J. C. Hardeman, Jr., Georgia Department of Natural Resources; A. J. Pepper, Georgia Perimeter College

Abstract: The HPS Atlanta Chapter (ACHPS) has embarked on a long-term plan to stabilize our past efforts supporting education. This effort involves obtaining funding; coordinating with state level agencies, and using a web based approach to ease the tasks of revising, maintaining and distributing materials, as well as providing technical support to teachers who elect to incorporate the material into their classrooms. To obtain the most teacher participation, significant effort was devoted to the development of ready to use educational units compliant with Georgia physical science performance criteria. In order to assess the readiness of the material, our Science Teacher Workshop Committee assembled lesson plans, supporting material, and equipment for hands-on demonstrations during the 2009 Georgia Science Teacher Association meeting. Materials provided in the workshop and outlined in this presentation include handouts addressing educational criteria, lesson plans, reference materials, directions for demonstrations, and links to additional resources for equipment, materials, and additional information. ACHPS contact information for continuing support was provided. Each teacher was also provided with a (CD) survey meter. This effort builds on previous workshops by incorporating material now available on the Internet. Results of follow-up surveys of participants and lessons learned are presented.

.   I-125 Plaque in Eye Melanoma Treatment: ALARA and Other Considerations DH Elder*, University of Colorado Hospital ; YA Hu, University of Colorado Hospital; J Strzelczyk, University of Colorado Hospital

Abstract: While ocular melanoma is a rare cancer, its treatment presents numerous challenges. Among the factors that determine the appropriate approach are the size and stage of cancer, and the likelihood of saving the eye and preserving vision. Several options are available for small and medium size ocular melanomas; they include surgery, radiation and laser therapy. Large melanomas are usually treated by extensive surgery that may involve enucleation (removal of the eyeball). Some medical centers have begun to treat these melanomas by irradiation with charged particles or with plaque brachytherapy utilizing Ru-106 or I-125 seeds. Considering better cure rate and in the interest of ALARA, ophthalmologists and radiation oncologists in our institution opted to utilize I-125 seeds in conjunction with eye applicators developed for the Phase III national study (COMS), Collaborative Ocular Melanoma Study. In addition to clinical and radiation safety aspects, medical and health physicists addressed technical, dosimetric and logistical considerations. They included questions such how to assure that occupational exposures for personnel preparing, transporting and handling the plaque remain ALARA, who should be placing the implant in the surgical field, and what precautions to take to assure that the general public exposure limits are not exceeded.

.   Evaluation of Skin Dose using GafChromic EBT Film Kellen Thuo*, Student ; Camille Lodwick, Professor ; David Hamby, Professor

Abstract: Hot particle skin contamination can produce highly localized doses from gamma and beta radiations. Although photon dosimetry is often not critical in hot-particle contamination, it may be significant because of beta-emission characteristics and/or the presence of protective clothing between the source and skin. The energy released by photons is a straightforward calculation; however, KERMA will overestimate the true absorbed dose at shallow depths during the buildup of electronic equilibrium. GafChromic EBT film is used to directly quantify this buildup of dose at shallow depths. The self-developing properties of GafChromic film, along with its effective Z of 6.8, make the film ideal to evaluate dose to tissue. Isotopes of various energies, ranging from 200keV to 3MeV, are used to evaluate dose to the skin at depths of 70, 100, 300 and 1000 microns. Dose is assessed using combinations of clothing thickness and air gaps (between clothing and skin). The film is layered at depths so as to provide data at the points of interest. Following the film exposure, each layer is scanned on an EPSON 10,000 XL flatbed scanner and analyzed by ISP FilmQA software. Estimates of dose are also made for the same scenarios using a photon/electron Monte Carlo transport method (MCNP5).

.   Real-Time Continuous Air Monitoring of Plutonium-239 Around a Manhattan Project-Era Nuclear Waste Site William Eisele*, Los Alamos National Laboratory ; Orval Hart, Los Alamos National Laboratory

Abstract: A commercially available, portable, lightweight alpha environmental continuous air monitor (ECAM) coupled with cell phone modem communications and in-house developed data acquisition and display software has been implemented for the remote monitoring of plutonium-239 in air around a Manhattan-era project waste site during remediation activities which are to start in the summer of 2009. This system has been developed and implemented to provide situational awareness of potential airborne releases from the remediation activities to the public located only 20 meters away downwind of the waste site. This is especially important because historical waste disposal records are not available and the actual inventory of plutonium-239 in waste and soil is unknown. Environmental air sampling stations have been deployed along the perimeter of the waste site, however, the turnaround time between the start of the sampling period and receipt of isotopic air sampling data is on the order of 4 to 6 weeks. The ECAM system should provide a more rapid, but less sensitive, means of identifying inadvertent releases of plutonium-239 to the environment than the air sampling stations. The ECAM itself has a vendor-developed curve fit algorithm to parse out counts due to short-lived radon progeny from plutonium-239 counts. Software has been developed to remotely acquire various types of data, e.g., concentration, dose, pump flow rate, raw counts, alpha energy spectra, from each ECAM on a periodic basis via a cell phone modem communications protocol. This data is then available for analysis and display via a web-based interface that is available from any desktop computer with appropriate access privileges. Thus far, 3 ECAMs have been deployed in the field and have collected data for approximately 6 months during the pre-operational phase of the remediation project.

.   Risk-based Fee Structure Spreadsheet MARTHA DIBBLEE*, Radiation Health Consulting

Abstract: ABSTRACT Using a simple Excel spreadsheet, operational data from a materials program can be entered to test a desired “bottom line”. The spreadsheet calculates hours worked (person-hours), numbers of licenses or facilities or devices, and inspection and licensing hours. Fees incorporate a risk factor for each license type. Author: DIBBLEE Martha GK 30 Sept 2008.

.   Urinary Polonium-210 and Lead-210 in a Population of Chinese Smokers and Nonsmokers Stephen Schayer*, New York University School of Medicine, Tuxedo, NY ; Qingshan Qu, New York University School of Medicine, Tuxedo, NY; Yanling Wang, Peking University Health Science Center, Beijing, PRC; Beverly Cohen, New York University School of Medicine, Tuxedo, NY

Abstract: In recent years, there has been renewed interest in the 210Po and 210Pb concentrations in cigarettes. We measured the 210Po and 210Pb levels in popular brands of Chinese cigarettes (mean=23 mBq/cig), and hypothesized that urinary 210Po and 210Pb levels could be used as tracers of exposure to cigarette smoke. Urine samples (24-hr) collected from 250 volunteers in suburban areas of Beijing were assayed for 210Po and 210Pb. The median(range) 210Pb activity of 9(4-17) mBq in nonsmokers was statistically less (p<0.001) than that of 13(4-33) mBq in smokers. In measurable samples, the median(range) 210Po activity of 13(5-49) mBq in nonsmokers was close to being statistically different (p=0.059) from that of 18(4-100) mBq in smokers. Although the urinary 210Po activity did not correlate with any available smoking index, the 210Pb activity was correlated (ρ=0.35) with the number of cigarettes smoked per day (CPD). In a simple linear regression model, for a 1-unit increase in CPD, there is an increase of 0.13 mBq in urinary 210Pb activity. This data was modeled, with dietary and inhalation intakes repeated once daily, using the ICRP human respiratory tract, gastrointestinal tract, and biokinetic models for 210Pb and 210Po. Because the respiratory deposition of cigarette smoke is not well understood, deposition parameters were adjusted (total deposition of 0.5) until the models predicted urinary levels that agreed with the measured results. When a daily intake of 38 mBq 210Pb and 210Po by inhalation of ambient air was assumed based upon past studies, the models indicated that daily dietary intakes of 90 mBq 210Pb and 100 mBq 210Po would produce steady-state urinary levels consistent with those measured in nonsmokers. The total committed effective dose from both 210Pb and 210Po intakes (dietary and ambient) was estimated to be 127 μSv/year. After considering the adjusted respiratory deposition parameters, it was determined that smoking 20 CPD adds 146 μSv/year to the total.

.   An Approach To Evaluation Of Strontium-90 Spatial Distribution In Calcified Biological Samples Using PCL Method Of Digital Autoradiography Victor Krivoshchapov*, Urals Research Center for Radiation Medicine, Russia ; Elena Shishkina, Urals Research Center for Radiation Medicine, Russia

Abstract: Knowledge of a radionuclide distribution in biological tissues is an actual problem in medicine, experimental physiology and radiobiology. A special attention in such investigations is paid to detection of Strontium-90 concentration in the calcified tissues because this radionuclide is a metabolic analogue of calcium and can be used as a biological marker. The method of digital autoradiography based on Image Plates of Photo Stimulable Luminescence (PSL) is usually applied for qualitative evaluations of spatial distribution of a radionuclide in samples. This study was aimed at development of a method for conversion of arbitrary results of Strontium-90 measurements in environmental samples to units of energy deposition that correspond to Strontium-90 concentration. Measurement of a sample contaminated by Strontium-90 with use of PSL image plates was simulated with MCNP 4Cb code. Response in a PSL plate obtained numerically was processed statistically and a smoothing functional approximating the data was obtained. Comparative analysis of the results numerical experiments and published data allows verification of the model and calculation of a normalization factor for conversion of relative units of the PSL response to Strontium-90 concentrations. The study shows that method of digital autoradiography using the PSL plates can be successfully applied for quantitative evaluation of two-dimensional distribution of Strontium-90 in macro samples.

.   Off-site Source Recovery Project - The Most Over Regulated Disposition Pathway? Joseph Tompkins*, LANL - OSRP

Abstract: In 1999, the Off-site Source Recovery Project (OSRP) at Los Alamos National Laboratory began accepting radioactive sealed sources from the US licensed sector. As the need for sealed source disposition evolved the project evolved into what maybe the most regulated disposition pathway in the US. As an operational Project at LANL, a DOE facility that performs work in the public sector, OSR Project incorporates DOE, NNSA, LASO, NMED, NRC, DOT, EPA, LWA, State, and guidance and regulation in its many processes to find compliant disposition pathways for excess and unwanted radioactive sealed sources. The process of assessing excess sealed sources for final disposition by OSRP is complex and fraught with issues. From initial assessment, on-site packaging, shipment, visual examination, and final disposition there is a maze of regulatory minutia to navigate. Just like a steamer on a river, occasionally the steamer hits a sandbar, and has to be pulled off. This poster session describes the regulatory pathway via a decision tree network in order to gain all necessary approvals for final source disposition. The decision network illuminates the problem of multiple and conflicting regulators, and how OSR Project has adapted to satisfy all stakeholder requirements.

.   Candian Source Repatriation - A New Beginning Leonard Manzanares*, Los Alamos National Laboratory

Abstract: In 2008, the Off-site Source Recovery Project (OSRP) at Los Alamos National Laboratory was contacted by the University of Ottawa (U of O), Ontario, Canada seeking to repatriate a US origin PuBe source. The source, a 32 gram PuBe produced by Nuclear Materials and Equipment Corporation (NUMEC) over 30 years ago, was excess and unwanted. In order to lower the security profile of the University the RSO was seeking disposition. The first attempt at disposition was for long term storage at a cost of $500,000 CAD. The high cost for longterm storage of these sources encouraged the RSO to seek any other less expensive disposition pathway. High cost was only the initial barrier for U of O in their efforts to disposition this unwanted source. As they quickly discovered, their efforts were complicated due to a lack of documentation on the source, and a lack of Type AF shipping containers in Canada. OSRP was a likely international partner for disposition of these US origin sealed sources, since OSRP had already participated in several international recoveries of PuBe & AmBe sources and had hardware ready to solve the problems presented. This poster discusses the operational requirements, problems, and outcome of the successful recovery operation.

.   Development And Testing Of Gallium Arsenide Photoconductive Detectors For Ultra Fast, High Dose Rate Pulsed Electron And Bremsstrahlung Radiation Measurements G Kharashvili*, Idaho State University ; V Makarashvili, Idaho State University; M. D. Mitchell, Idaho State University; W Beezhold, Idaho State University; T. F. Gesell, Idaho State University; W. L. Wingert, University of Utah

Abstract: Real time radiation dose measurements are challenging in high dose rate environments such as those used for studying radiation effects on electronic devices or biological agents. Dosimetry needs at particle accelerator facilities require development of devices with fast (10s of picoseconds) response to pulsed radiation, linear response over a wide range of dose rates (up to E+11 Gy/s), high resistance to radiation damage, and successful operation in mixed gamma and neutron environments. Operation of GaAs PCDs (gallium arsenide photoconductive detectors) in pulsed electron and bremsstrahlung radiation fields is investigated. Neutron irradiation was used to cause displacement damage in crystalline lattice of GaAs. Creation of stable defect complexes introduces effective recombination and trapping centers, causing decrease in the charge carrier mobility and life time, hence improving time-response characteristics of these devices at the expense of their sensitivity. PCDs were fabricated from 3 different size, VGF (vertical gradient freeze) grown single crystal wafer samples with 3 different neutron irradiation levels (0, ~E+14, and 5 E+15 n/cm^2 (1-MeV (GaAs) equivalent). Detector operation was studied under 7 to 38-MeV electron pulses produced by linear accelerators operating at the S-band frequency of 2.8-GHz and L-band frequency of 1.3-GHz, and a 32-ns long, 7-MeV maximum energy bremsstrahlung pulses produced by a pulse-power accelerator. Improvement of the detector speed at the expense of its sensitivity as a function of neutron irradiation level is shown. Dose-rate ranges of application of the PCDs are determined (up to E+8 Gy/s) and calibration curves are presented. This work is funded by the DoD under contract # FA8650-04-2-6541. Special thanks to Dr. John Rauch and Dr. Miriam Rauch of Nu-Trek Inc. for their contributions.



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