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Health physics manual of good practices for tritium facilities

Description: The purpose of this document is to provide written guidance defining the generally accepted good practices in use at Department of Energy (DOE) tritium facilities. A {open_quotes}good practice{close_quotes} is an action, policy, or procedure that enhances the radiation protection program at a DOE site. The information selected for inclusion in this document should help readers achieve an understanding of the key radiation protection issues at tritium facilities and provide guidance as to what characterizes excellence from a radiation protection point of view. The ALARA (As Low as Reasonable Achievable) program at DOE sites should be based, in part, on following the good practices that apply to their operations.
Date: December 1, 1991
Creator: Blauvelt, R.K.; Deaton, M.R. & Gill, J.T.
Partner: UNT Libraries Government Documents Department

Baseline risk assessment of ground water contamination at the Uranium Mill Tailings Site near Lakeview, Oregon. Revision 2

Description: The U.S. Department of Energy (DOE) Uranium Mill Tailings Remedial Action (UMTRA) Project consists of the Surface Project (Phase I) and the Ground Water Project (Phase II). Under the UMTRA Surface Project, tailings, contaminated soil, equipment, and materials associated with the former uranium ore processing at UMTRA Project sites are placed into disposal cells. The cells are designed to reduce radon and other radiation emissions and to minimize further contamination of ground water. Surface cleanup at the UMTRA Project site near Lakeview, Oregon, was completed in 1989. The mill operated from February 1958 to November 1960. The Ground Water Project evaluates the nature and extent of ground water contamination that resulted from the uranium ore processing activities. The Ground Water Project is in its beginning stages. Human health may be at risk from exposure to ground water contaminated by uranium ore processing. Exposure could occur by drinking water pumped out of a hypothetical well drilled in the contaminated areas. Ecological risks to plants or animals may result from exposure to surface water and sediment that have received contaminated ground water. A risk assessment describes a source of contamination, how that contamination reaches people and the environment, the amount of contamination to which people or the ecological environment may be exposed, and the health or ecological effects that could result from that exposure. This risk assessment is a site-specific document that will be used to evaluate current and potential future impacts to the public and the environment from exposure to contaminated ground water. The results of this evaluation and further site characterization will determine whether any action is needed to protect human health or the ecological environment.
Date: March 1, 1996
Partner: UNT Libraries Government Documents Department

The relative physiological and toxicological properties of americium and plutonium

Description: The relative physiological and toxicological properties of americium and plutonium have been studied following their intravenous administration to rats. The urinary and fecal excretion of americium was similar to that of plutonium administered as Pu(N0{sub 3}){sub 4}. The deposition of americium the tissues and organs of the rat was also similar to that observed for plutonium. The liver and the skeleton were the major sites of deposition. Zirconium citrate administered 15 minutes after injection of americium increased the urinary excretion of americium and decreased the amount found in the liver and the skeleton at 4 and 16 days. LD{sub 30}{sup 50} studies showed americium was slightly less toxic when given in the acute toxic range than was plutonium. The difference was, however, too slight to be important in establishing a larger tolerance does for americium. Survival studies, hematological observations, bone marrow observations, comparison of tumor incidence and the incidence of skeletal abnormalities indicated that americium and plutonium have essentially the same chronic toxicity when given on an equal {mu}c. basis. These studies support the conclusion that the tolerance values for americium should be essentially the same as those for Plutonium.
Date: November 15, 1951
Creator: Carter, R.E.; Busch, E. & Johnson, O.
Partner: UNT Libraries Government Documents Department

Centrifuge workers study. Phase II, completion report

Description: Phase II of the Centrifuge Workers Study was a follow-up to the Phase I efforts. The Phase I results had indicated a higher risk than expected among centrifuge workers for developing bladder cancer when compared with the risk in the general population for developing this same type of cancer. However, no specific agent could be identified as the causative agent for these bladder cancers. As the Phase II Report states, Phase I had been limited to workers who had the greatest potential for exposure to substances used in the centrifuge process. Phase II was designed to expand the survey to evaluate the health of all employees who had ever worked in Centrifuge Program Departments 1330-1339 but who had not been interviewed in Phase I. Employees in analytical laboratories and maintenance departments who provided support services for the Centrifuge Program were also included in Phase II. In December 1989, the Oak Ridge Associated Universities (ORAU), now known as Oak Ridge Institute for Science and Education (ORISE), was contracted to conduct a follow-up study (Phase II). Phase H of the Centrifuge Workers Study expanded the survey to include all former centrifuge workers who were not included in Phase I. ORISE was chosen because they had performed the Phase I tasks and summarized the corresponding survey data therefrom.
Date: September 1, 1994
Creator: Wooten, H.D.
Partner: UNT Libraries Government Documents Department

Skin dose measurement with MICROSPEC-2{trademark}

Description: For many years, the Eberline HP-260{trademark} beta detectors were used for skin dose measurements at Los Alamos National Laboratory. This detector does not measure the beta spectrum and the skin dose can only be determined if the contaminating radioactive isotope is known. A new product MICROSPEC-2{trademark}, has been developed which consists of a small portable computer with a multichannel analyzer and a beta probe consisting of a phoswich detector. The system measures the beta spectrum and automatically folds in the beta fluence-to-dose conversion function to yield the skin dose.
Date: October 1, 1997
Creator: Hsu, H.H.; Chen, J.; Ing, H.; Clifford, E.T.H. & McLean, T.
Partner: UNT Libraries Government Documents Department

Multimedia Environmental Pollutant Assessment System (MEPAS{reg_sign}): Exposure pathway and human health impact assessment models

Description: The Multimedia Environmental Pollutant Assessment System (MEPAS) provides physics-based models for human health risk assessment for radioactive and hazardous pollutants. MEPAS analyzes pollutant behavior in various media (air, soil, groundwater and surface water) and estimates transport through and between media and exposure and impacts to the environment, to the maximum individual, and to populations. MEPAS includes 25 exposure pathway models, a database with information on more than 650 contaminants, and a sensitivity module that allows for uncertainty analysis. Four major transport pathways are considered in MEPAS: groundwater, overland, surface water, and atmospheric. This report describes the exposure pathway and health impact assessment component of MEPAS, which provides an estimate of health impacts to selected individuals and populations from exposure to pollutants. The exposure pathway analysis starts with pollutant concentration in a transport medium and estimates the average daily dose to exposed individuals from contact with the transport medium or a secondary medium contaminated by the transport medium. The average daily dose is then used to estimate a measure of health impact appropriate to the type of pollutant considered. Discussions of the exposure pathway models include the assumptions and equations used to convert the transport medium concentrations to exposure medium concentrations. The discussion for a given exposure pathway defines the transport pathways leading to the exposure, the special processes considered in determining the pollutant concentration in the exposure medium, and the exposure model used to estimate the average daily dose. Models for the exposure pathway and health impact assessments require definition of several parameters. A summary of the notation used for these parameters is provided.
Date: May 1995
Creator: Strenge, D. L. & Chamberlain, P. J.
Partner: UNT Libraries Government Documents Department

DNA Repair Enzyme-Liposomes: Human Skin Cancer Prevention

Description: This project centered on responses of human cells to ultraviolet radiation at the fundamental and practical levels. At the fundamental levels, the relation of DNA damage to cell signaling events such as cytokine induction were studied; paths in human cells for dealing with DNA damage were studied at the nucleotide sequence level. At the practical, new, effective and inexpensive UVB filters were devised and characterized; further, to make low frequency DNA damage quantitation more generally available, a commercially-obtainable electrophoretic mode (Contour Clamped Homogeneous Electric Field) was tested and determined to give good dispersions of high molecular length DNAs.
Date: September 16, 1999
Partner: UNT Libraries Government Documents Department

MEASUREMENTS OF THE PROPERTIES OF BERYLLIUM FOIL

Description: The electrical conductivity of beryllium at radio frequency (800 MHz) and liquid nitrogen temperature were investigated and measured. This summary addresses a collection of beryllium properties in the literature, an analysis of the anomalous skin effect, the test model, the experimental setup and improvements, MAFIA simulations, the measurement results and data analyses. The final results show that the conductivity of beryllium is not as good as indicated by the handbook, yet very close to copper at liquid nitrogen temperature.
Date: March 31, 2000
Creator: ZHAO,Y. & WANG,H.
Partner: UNT Libraries Government Documents Department

Effects of radioactive hot particles on pig skin

Description: The purpose of these studies was to determine the incidence and severity of lesions resulting from very localized deposition of dose to skin from small (< 0.5 mm) discrete radioactive particles as produced in the work environments of nuclear reactors. Hanford mini-pigs were exposed, both on a slightly off the skin, to localized replicate doses from 0.31 to 64 Gy (averaged over 1 cm{sup 2} at 70 {mu}m depth unless noted otherwise) using Sc-46, Yb-175, Tm-170, and fissioned UC{sub 2} isotopes having maximum beta-particle energies from about 0.3 to 3 MeV. Erythema and scabs (indicating ulceration) were scored for up to 71 days post-irradiation. The responses followed normal cumulative probability distributions, and therefore, no true threshold could be defined. Hence, 10 and 50% scab incidence rates were deduced using probit analyses. The lowest dose which produced 10% incidence was about 1 Gy for Yb-175 (0.5 MeV maximum energy) beta particle exposures, and about 3 to 9 Gy for other isotopes. The histopathology of lesions was determined at several doses. Single exposures to doses as large as 1,790 Gy were also given, and results were observed for up to 144 days post-exposure. Severity of detriment was estimated by analyzing the results in terms of lesion diameter, persistence, and infection. Over 1,100 sites were exposed. Only two exposed sites became infected after doses near 5000 Gy; the lesions healed quickly on treatment. 105 refs., 145 figs., 47 tabs.
Date: June 1997
Creator: Kaurin, D. G.; Baum, J. W. & Schaefer, C. W.
Partner: UNT Libraries Government Documents Department

Protective measures for personnel

Description: This document addresses radiation protection concerns for workers in the experimental laboratories and production plants where nuclear fission piles are being used. A broad in-depth discussion is provided based with the experiences gained in the Manhattan Project and being applied to contemporary activities. Discussion is thorough and encompasses control of external irradiations including alpha, beta, gamma, and neutron radiations; and control of radioactivity within the body by control of inhalation, ingestion, and entrance through skin or wounds. General measures for the control of radiation hazards is addressed by provision of clothing and waste disposal. An Appendix 1 is entitled General Rules and Procedures Concerning Activity Hazards.
Date: December 13, 1946
Creator: Nickson, J.J.
Partner: UNT Libraries Government Documents Department

The specific activity of tritium in the organic components of the skin and fat of man following eight months` chronic exposure to HTO in body fluids

Description: A healthy 39-year-old male weighing 65 kg was exposed for a period of 8 months to varying levels of HTO. The average tritium activity in body fluids over the entire period was 23 {mu}c/liter. A few weeks after exposure, when the HTO activity in body fluids had declined to about 0.2 {mu}c/liter, a biopsy was pe formed on skin and fat taken from the region of the lower abdomen, and the material was analyzed for tritium activity. The skin showed an average activity equivalent to 0.4 {mu}c/kg of dry tissue and the fat about 0.3 {mu}c/kg of dry tissue. The radiation dose per unit time from these activities was only 1 to 2 percent of the radiation dose per unit time during the 8-month exposure period. It was concluded that the radiation hazard due to retention of tritium in the organic components of these tissues of man after chronic exposure was negligible compared to the radiation hazard from HTO activity in the body fluids which was necessary to induce the activity into the organic components. Comparable experiments on mice previously reported indicate that this conclusion may hold for all tissues in the body. The water content of the skin and fat of man was found to be 71 percent and 20 percent, respectively, on the basis of the wet weight. The hydrogen content of skin was 7.6 per cent, and of fat 11.4 percent, of the dry weight of the tissue.
Date: October 1, 1952
Creator: Pinson, E.A.; Anderson, E.C. & Lotz, V.
Partner: UNT Libraries Government Documents Department

Summary of research of the section on pharmacology. Progress report for December 1944

Description: Various studies relating the biological and behavioral effect of several uranium fluorides and chlorides as well as fluorine and oxyflourides are related. Most of these studies involved rats, guinea pigs, rabbits or dogs. Route of administration included inhalation, ingestion, or application to the skin.
Date: December 31, 1944
Creator: Hodge, H.C.
Partner: UNT Libraries Government Documents Department

Telemetric heat stress monitor (THSM) spin-offs

Description: This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This project sought to investigate spin-offs of the telemetric heat stress monitoring system (THSM) developed at LANL. Hazardous-materials workers and firefighters wear clothing that protects them from external hazards, but the sealed environment of a protective suit makes its wearer susceptible to heat stress. Heat stress occurs when the body`s natural cooling mechanisms fail: it can cause collapse and death. The THSM warns both workers and remote monitoring personnel of incipient heat stress by monitoring and responding to elevations of workers` skin temperatures and heart rates. The technology won a 1994 R & D 100 award.
Date: July 1996
Creator: Berkbigler, L.; Bradley, O.; Lopez, R.; Martinez, D. & Stampfer, J.
Partner: UNT Libraries Government Documents Department

Adaptive Response Against Spontaneous Neoplastic Transformation In Vitro Induced by Ionizing Radiation

Description: The goal of this project was to establish a dose response curve for radiation-induced neoplastic transformation of HeLa x skin fibroblast human hybrid cells in vitro under experimental conditions were an adaptive response, if it were induced, would have an opportunity to be expressed. During the first two years of the grant an exhaustive series of experiments were performed and the resulting data were reported at the 2000 Annual Meeting of the Radiation Research Society and then Subsequently published. The data showed that an adaptive response against spontaneous neoplastic transformation was seen up to doses of 10cGy of Cs-137 gamma rays. At dose of 30, 50 and 100 cGy the transformation frequencies were above background. This indicated that for this system, under the specific experimental conditions used, there was a threshold of somewhere between 10 and 30 cGy. The results also indicated some unexpected, though very interesting, correlations with relative risk estimates made from human epidemiologic studies.
Date: November 10, 2003
Creator: J. Leslie Redpath, Ph.D.
Partner: UNT Libraries Government Documents Department

Revisiting the Anomalous rf Field Penetration into a Warm Plasma

Description: Radio-frequency [rf] waves do not penetrate into a plasma and are damped within it. The electric field of the wave and plasma current are concentrated near the plasma boundary in a skin layer. Electrons can transport the plasma current away from the skin layer due to their thermal motion. As a result, the width of the skin layer increases when electron temperature effects are taken into account. This phenomenon is called anomalous skin effect. The anomalous penetration of the rf electric field occurs not only for transversely propagating to the plasma boundary wave (inductively coupled plasmas) but also for the wave propagating along the plasma boundary (capacitively coupled plasmas). Such anomalous penetration of the rf field modifies the structure of the capacitive sheath. Recent advances in the nonlinear, non-local theory of the capacitive sheath are reported. It is shown that separating the electric field profile into exponential and non-exponential parts yields an efficient qualitative and quantitative description of the anomalous skin effect in both inductively and capacitively coupled plasma.
Date: June 24, 2005
Creator: Kaganovich, Igor D.; Polomarov, Oleg V. & Theodosiou, Constantine E.
Partner: UNT Libraries Government Documents Department

Anomalous Skin Effect for Anisotropic Electron Velocity Distribution Function

Description: The anomalous skin effect in a plasma with a highly anisotropic electron velocity distribution function (EVDF) is very different from skin effect in a plasma with the isotropic EVDF. An analytical solution was derived for the electric field penetrated into plasma with the EVDF described as a Maxwellian with two temperatures Tx &gt;&gt; Tz, where x is the direction along the plasma boundary and z is the direction perpendicular to the plasma boundary. The skin layer was found to consist of two distinctive regions of width of order nTx/w and nTz/w, where nTx,z/w = (Tx,z/m)1/2 is the thermal electron velocity and w is the incident wave frequency.
Date: February 19, 2004
Creator: Kaganovich, Igor; Startsev, Edward & Shvets, Gennady
Partner: UNT Libraries Government Documents Department

Landau Damping and Anomalous Skin Effect in Low-pressure Gas Discharges: Self-consistent Treatment of Collisionless Heating

Description: In low-pressure discharges, where the electron mean free path is larger or comparable with the discharge length, the electron dynamics is essentially nonlocal. Moreover, the electron energy distribution function (EEDF) deviates considerably from a Maxwellian. Therefore, an accurate kinetic description of the low-pressure discharges requires knowledge of the nonlocal conductivity operator and calculation of the non-Maxwellian EEDF. The previous treatments made use of simplifying assumptions: a uniform density profile and a Maxwellian EEDF. In the present study a self-consistent system of equations for the kinetic description of nonlocal, nonuniform, nearly collisionless plasmas of low-pressure discharges is reported. It consists of the nonlocal conductivity operator and the averaged kinetic equation for calculation of the non-Maxwellian EEDF. This system was applied to the calculation of collisionless heating in capacitively and inductively coupled plasmas. In particular, the importance of accounting for the nonuniform plasma density profile for computing the current density profile and the EEDF is demonstrated. The enhancement of collisionless heating due to the bounce resonance between the electron motion in the potential well and the external radio-frequency electric field is investigated. It is shown that a nonlinear and self-consistent treatment is necessary for the correct description of collisionless heating.
Date: January 30, 2004
Creator: Kaganovich, Igor D.; Polomarov, Oleg V. & Theodosiou, Constantine E.
Partner: UNT Libraries Government Documents Department

Structural and Functional Studies on Nucleotide Excision Repair From Recognition to Incision.

Description: Maintenance of the correct genetic information is crucial for all living organisms because mutations are the primary cause of hereditary diseases, as well as cancer and may also be involved in aging. The importance of genomic integrity is underscored by the fact that 80 to 90% of all human cancers are ultimately due to DNA damage. Among the different repair mechanisms that have evolved to protect the genome, nucleotide excision repair (NER) is a universal pathway found in all organisms. NER removes a wide variety of bulky DNA adducts including the carcinogenic cyclobutane pyrimidine dimers induced by UV radiation, benzo(a)pyrene-guanine adducts caused by smoking and the guanine-cisplatin adducts induced by chemotherapy. The importance of this repair mechanism is reflected by three severe inherited diseases in humans, which are due to defects in NER: xeroderma pigmentosum, Cockayne's syndrome and trichothiodystrophy.
Date: January 1, 2001
Creator: Kisker, Caroline
Partner: UNT Libraries Government Documents Department

Mathematical models and specific absorbed fractions of photon energy in the nonpregnant adult female and at the end of each trimester of pregnancy

Description: Mathematical phantoms representing the adult female at three, six, and nine months of gestation are described. They are modifications of the 15-year-old male/adult female phantom (15-AF phantom) of Cristy and Eckerman (1987). The model of uterine contents includes the fetus, fetal skeleton, and placenta. The model is suitable for dose calculations for the fetus as a whole; individual organs within the fetus (other than the skeleton) are not modeled. A new model for the nonpregnant adult female is also described, comprising (1) the 15-AF phantom; (2) an adjustment to specific absorbed fractions for organ self-dose from photons to better match Reference Woman masses; and (3) computation of specific absorbed fractions with Reference Woman masses from ICRP Publication 23 for both penetrating and nonpenetrating radiations. Specific absorbed fractions for photons emitted from various source regions are tabulated for the new non;pregnant adult female model and the three pregnancy models.
Date: May 8, 1995
Creator: Stabin, M.G.; Watson, E.E.; Cristy, M.; Ryman, J.C.; Eckerman, K.F.; Davis, J.L. et al.
Partner: UNT Libraries Government Documents Department

Results of analyses of fur samples from the San Joaquin Kit Fox and associated soil and water samples from the Naval Petroleum Reserve No. 1, Tupman, California

Description: The purpose of this study was to determine whether analysis of the elemental content of fur from San Joaquin kit foxes (Vulpes macrotis mutica) and of water and soil from kit fox habitats could be used to make inferences concerning the cause of an observed decline in the kit fox population on Naval Petroleum Reserve No. 1 (NPR-1). Fur samples that had been collected previously from NPR-1, another oil field (NPR-2), and two sites with no oil development were subjected to neutron activation analysis. In addition, soil samples were collected from the home ranges of individual foxes from undisturbed portions of major soil types on NPR-1 and from wastewater samples were collected from tanks and sumps and subjected to neutron activation analysis. Most elemental concentrations in fur were highest at Camp Roberts and lowest on the undeveloped portions of NPR-I. Fur concentrations were intermediate on the developed oil fields but were correlated with percent disturbance and with number of wells on NPR-1 and NPR-2. The fact that most elements covaried across the range of sites suggests that some pervasive source such as soil was responsible. However, fur concentrations were not correlated with soft concentrations. The kit foxes on the developed portion of NPR-1 did not have concentrations of elements in fur relative to other sites that would account for the population decline in the early 1980s. The oil-related elements As, Ba, and V were elevated in fox fur from oil fields, but only As was sufficiently elevated to suggest a risk of toxicity in individual foxes. However, arsenic concentrations suggestive of sublethal toxicity were found in only 0.56% of foxes from developed oil fields, too few to account for a population decline.
Date: December 1, 1992
Creator: Suter, G.W. II; Rosen, A.E.; Beauchamp, J.J. (Oak Ridge National Lab., TN (United States)) & Kato, T.T. (EG and G Energy Measurements, Inc., Tupman, CA (United States))
Partner: UNT Libraries Government Documents Department