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Biological Manipulation of Migration Rate: The Use of Advanced Photoperiod to Accelerate Smoltification in Yearling Chinook Salmon, Annual Report 1989.

Description: Research was conducted to assess the feasibility of biologically manipulating physiological development and migratory behavior of yearling spring chinook salmon, Oncorhynchus tshawytscha. At Dworshak National Fish Hatchery, treatment groups were exposed to a variety of advanced photoperiod cycles preceding release to accelerate smolt development. Physiological development and migratory performance were described for all groups. The treatments included a 14-week exposure to a 3-month advanced photoperiod cycle, an 18-week exposure to a 3-month advanced photoperiod cycle, and an 18-week exposure to a 4-month advanced photoperiod cycle. Two additional groups, an 18-week exposure to a 3-month advanced photoperiod and a control equivalent, were reared at an elevated water temperature (11{degrees}C) for 2 weeks prior to release. Results indicated that the treated fish which were the most physiologically advanced at release were detected in the highest proportion at collector dams and also migrated fastest downstream. 26 refs., 10 figs., 5 tabs.
Date: January 1, 1991
Creator: Giorgi, Albert E.; Muir, William D. & Zaugg, Waldo S.
Partner: UNT Libraries Government Documents Department

X-ray and radioiodine dose to thyroid follicular cells

Description: Radiation doses to the epithelial cells of thyroid follicles have been calculated for internal exposure by radionuclides of iodine and by secondary radiations created as a result of interactions of externally administered x rays with iodine naturally occurring in the thyroid. Calculations were performed for the thyroids of subjects ranging from the newborn to the adult male. Results for internal radionuclides are reported as the dose rate to follicular-cell nuclei per unit specific activity of the radionuclide in the thyroid as a whole, i.e., as the specific S value'' as used in the MIRD method for internal dosimetry. Results for x rays are reported as the response function, i.e., the absorbed dose per unit fluence of primary x rays. Dose rates are subdivided into internal and external components, the former from radiations emitted within the colloid volume of any one follicle, and the latter from radiations emitted throughout the thyroid in follicles surrounding that one follicle. 37 refs., 5 figs., 3 tabs.
Date: January 1, 1991
Creator: Faw, R.E. (Kansas State Univ., Manhattan, KS (USA). Dept. of Nuclear Engineering); Eckerman, K.F. & Ryman, J.C. (Oak Ridge National Lab., TN (USA))
Partner: UNT Libraries Government Documents Department

FY 1992 task plans for the Hanford Environmental Dose Reconstruction Project

Description: Phase 1 of the HEDR Project was designed to develop and demonstrate a method for estimating radiation doses people may have received from Hanford Site operations since 1944. The method researchers developed relied on a variety of measured and reconstructed data as input to a modular computer model that generates dose estimates and their uncertainties. As part of Phase 1, researchers used the reconstructed data and computer model to calculate preliminary dose estimates for populations from limited radionuclides, in a limited geographical area and time period. Phase 1 ended in FY 1990. In February 1991, the TSP decided to shift the project planning approach away from phases--which were centered around completion of major portions of technical activities--to individual fiscal years (FYs), which span October of one year through September of the next. Therefore, activities that were previously designated to occur in phases are now designated in an integrated schedule to occur in one or more of the next fiscal years into FY 1995. Task plans are updated every 6 months. In FY 1992, scientists will continue to improve Phase 1 data and models to calculate more accurate and precise dose estimates. The plan for FY 1992 has been prepared based on activities and budgets approved by the Technical Steering Panel (TSP) at its meeting on August 19--20, 1991. The activities can be divided into four categories: (1) model and data evaluation activities, (2) additional dose estimates, (3) model and data development activities, and (4) technical and communication support. 3 figs., 2 tabs.
Date: October 1, 1991
Partner: UNT Libraries Government Documents Department

Phase 1 of the Hanford Environmental Dose Reconstruction Project

Description: The work described in this report was prompted by the public's concern about potential effect from the radioactive materials released from the Hanford Site. The Hanford Environmental Dose Reconstruction (HEDR) Project was established to estimate radiation dose the public might have received from the Hanford Site since 1944, when facilities began operating. Phase 1 of the HEDR Project is a pilot'' or demonstration'' phase. The objectives of this initial phase were to determine whether enough historical information could be found or reconstructed to be used for dose estimation and develop and test conceptual and computational models for calculating credible dose estimates. Preliminary estimates of radiation doses were produced in Phase 1 because they are needed to achieve these objectives. The reader is cautioned that the dose estimates provided in this and other Phase 1 HEDR reports are preliminary. As the HEDR Project continues, the dose estimates will change for at least three reasons: more complete input information for models will be developed; the models themselves will be refined; and the size and shape of the geographic study area will change. This is one of three draft reports that summarize the first phase of the four-phased HEDR Project. This, the Summary Report, is directed to readers who want a general understanding of the Phase 1 work and preliminary dose estimates. The two other reports -- the Air Pathway Report and the Columbia River Pathway Report -- are for readers who understand the radiation dose assessment process and want to see more technical detail. Detailed descriptions of the dose reconstruction process are available in more than 20 supporting reports listed in Appendix A. 32 refs., 46 figs.
Date: August 1, 1991
Partner: UNT Libraries Government Documents Department

FY 1991 project plan for the Hanford Environmental Dose Reconstruction Project, Phase 2

Description: Phase 1 of the Hanford Environmental Dose Reconstruction Project was designed to develop and demonstrate a method for estimating radiation doses people may have received from Hanford Site operations since 1944. The method researchers developed relied on a variety of measured and reconstructed data as input to a modular computer model that generates dose estimates and their uncertainties. As part of Phase 1, researchers used the reconstructed data and computer model to calculate preliminary dose estimates for populations in a limited geographical area and time period. Phase 2, now under way, is designed to evaluate the Phase 1 data and model and improve them to calculate more accurate and precise dose estimates. Phase 2 will also be used to obtain preliminary estimates of two categories of doses: for Native American tribes and for individuals included in the pilot phase of the Hanford Thyroid Disease Study (HTDS). TSP Directive 90-1 required HEDR staff to develop Phase 2 task plans for TSP approval. Draft task plans for Phase 2 were submitted to the TSP at the October 11--12, 1990 public meeting, and, after discussions of each activity and associated budget needs, the TSP directed HEDR staff to proceed with a slate of specific project activities for FY 1991 of Phase 2. This project plan contains detailed information about those activities. Phase 2 is expected to last 15--18 months. In mid-FY 1991, project activities and budget will be reevaluated to determine whether technical needs or priorities have changed. Separate from, but related to, this project plan, will be an integrated plan for the remainder of the project. HEDR staff will work with the TSP to map out a strategy that clearly describes end products'' for the project and the work necessary to complete them. This level of planning will provide a framework within ...
Date: February 1, 1991
Partner: UNT Libraries Government Documents Department

Health effects models for nuclear power plant accident consequence analysis: Modifications of models resulting from recent reports on health effects of ionizing radiation

Description: The Nuclear Regulatory Commission has sponsored several studies to identify and quantify the potential health effects of accidental releases of radionuclides from nuclear power plants. The most recent health effects models resulting from these efforts were published in two reports, NUREG/CR-4214, Rev. 1, Part 1 (1990) and Part 2 (1989). Several major health effects reports have been published recently that may impact the health effects models presented in these reports. This addendum to the Part 2 (1989) report, provides a review of the 1986 and 1988 reports by the United Nations Scientific Committee on the Effects of Atomic Radiation, the National Academy of Sciences/National Research Council BEAR 5 Committee report and Publication 60 of the International Commission on Radiological Protection as they relate to this report. The three main sections of this addendum discuss early occurring and continuing effects, late somatic effects, and genetic effects. The major changes to the NUREG/CR-4214 health effects models recommended in this addendum are for late somatic effects. These changes reflect recent changes in cancer risk factors that have come from longer followup and revised dosimetry in major studies like that on the Japanese A-bomb survivors. The results presented in this addendum should be used with the basic NUREG/CR-4214 reports listed above to obtain the most recent views on the potential health effects of radionuclides released accidentally from nuclear power plants. 48 refs., 4 figs., 24 tabs.
Date: August 1, 1991
Creator: Abrahamson, S. (Wisconsin Univ., Madison, WI (United States)); Bender, M.A. (Brookhaven National Lab., Upton, NY (United States)); Boecker, B.B.; Scott, B.R. (Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (United States). Inhalation Toxicology Research Inst.) & Gilbert, E.S. (Pacific Northwest Lab., Richland, WA (United States))
Partner: UNT Libraries Government Documents Department

Air pathway report: Phase I of the Hanford Environmental Dose Reconstruction Project

Description: Phase 1 of the air-pathway portion of the Hanford Environmental Dose Reconstruction (HEDR) Project sought to determine whether dose estimates could be calculated for populations in the 10 counties nearest the Hanford Site from atmospheric releases of iodine-131 from the site from 1944--1947. Phase 1 demonstrated the following: HEDR-calculated source-term estimates of iodine-131 releases to the atmosphere were within 20% of previously published estimates; calculated vegetation concentrations of iodine-131 agree well with previously published measurements; the highest of the Phase 1 preliminary dose estimates to the thyroid are consistent with independent, previously published estimates of doses to maximally exposed individuals; and, relatively crude, previously published measurements of thyroid burdens for Hanford workers are in the range of average burdens that the HEDR model estimated for similar reference individuals'' for the period 1944--1947. Preliminary median dose estimates summed over the year 1945--1947 for the primary pathway, air-pasture-cow-milk-thyroid, ranged from low median values of 0.006 rad for upwind adults who obtained milk from backyard cows not on pasture to high median values of 68.0 rad for downwind infants who drank milk from pasture-fed cows. Extremes of the estimated range are a low of essentially zero to upwind adults and a high of almost 3000 rem to downwind infants. 37 refs., 37 figs., 2 tabs.
Date: July 1, 1991
Partner: UNT Libraries Government Documents Department

A preliminary examination of audience-related communications issues for the Hanford Environmental Dose Reconstruction Project

Description: The Hanford Environmental Dose Reconstruction (HEDR) Project will estimate radiation doses people may have received from exposure to radioactive materials released during past operations at the US Department of Energy's (DOE) Hanford Site near Richland, Washington. The HEDR Project was initiated in response to public concerns about possible health impacts from past releases of radioactive materials from Hanford. The TSP recognized early in the project that special mechanisms would be required to effectively communicate to the many different concerned audiences. Accordingly, the TSP directed PNL to examine methods for communicating causes and effects of uncertainties in the dose estimates. After considering the directive and discussing it with the Communications Subcommittee of the TSP, PNL undertook a broad investigation of communications methods to consider for inclusion in the TSP's current communications program. As part of this investigation, a literature review was conducted regarding risk communications. A key finding was that, in order to successfully communicate risk-related information, a thorough understanding of the knowledge level, concerns and information needs of the intended recipients (i.e., the audience) is necessary. Hence, a preliminary audience analysis was conducted as part of the present research. This report summarizes the results of this analysis. 1 ref., 9 tabs.
Date: April 1, 1991
Creator: Holmes, C.W.
Partner: UNT Libraries Government Documents Department

Evaluation of thyroid radioactivity measurement data from Hanford workers, 1944--1946

Description: This report describes the preliminary results of an evaluation conducted in support of the Hanford Environmental Dose Reconstruction (HEDR) Project. The primary objective of the HEDR Project is to estimate the radiation doses that populations could have received from nuclear operations at the Hanford Site since 1944. A secondary objective is to make information that HEDR staff members used in estimate radiation doses available to the public. The objectives of this report to make available thyroid measurement data from Hanford workers for the year 1944 through 1946, and to investigate the suitability of those data for use in the HEDR dose estimation process. An important part of this investigation was to provide a description of the uncertainty associated with the data. Lack of documentation on thyroid measurements from this period required that assumptions be made to perform data evaluations. These assumptions introduce uncertainty into the evaluations that could be significant. It is important to recognize the nature of these assumptions, the inherent uncertainty, and the propagation of this uncertainty, and the propagation of this uncertainty through data evaluations to any conclusions that can be made by using the data. 15 refs., 1 fig., 5 tabs.
Date: May 1, 1991
Creator: Ikenberry, T.A.
Partner: UNT Libraries Government Documents Department

FY 1991 Task plans for the Hanford Environmental Dose Reconstruction Project

Description: The purpose of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate radiation doses from Hanford Site operations since 1944 to populations and individuals. The objectives of work in Fiscal Year (FY) 1991 are to analyze data and models used in Phase 1 and restructure the models to increase accuracy and reduce uncertainty in dose estimation capability. Databases will be expanded and efforts will begin to determine the appropriate scope (space, time, radionuclides, pathways and individuals/population groups) and accuracy (level of uncertainty in dose estimates) for the project. Project scope and accuracy requirements, once defined, can be translated into additional model and data requirements later in the project. Task plans for FY 1991 have been prepared based on activities approved by the Technical Steering Panel (TSP) in October 1990 and mid-year revisions discussed at the TSP planning/budget workshop in February 1991. The activities can be divided into two broad categories: (1) model and data development and evaluation, (2) project, technical and communication support. 3 figs., 1 tab.
Date: April 1, 1991
Partner: UNT Libraries Government Documents Department

FY 1993 task plans for the Hanford Environmental Dose Reconstruction Project

Description: The purpose of the Hanford Environmental Dose Reconstruction (HEDR) Project is to estimate radiation doses from Hanford Site operations since 1944 to individuals and populations. The primary objective of work to be performed in FY 1993 is to complete the source term estimates and dose estimates for key radionuclides for the air and river pathways. At the end of FY 1993, the capability will be in place to estimate doses for individuals in the extended (32-county) study area, 1944--1991. Native American research will continue to provide input for tribal dose estimates. In FY 1993, the Technical Steering Panel (TSP) will decide whether demographic and river pathways data collection should be extended beyond FY 1993 levels. The FY 1993 work scopes and milestones in this document are based on the work plan discussed at the TSP Budget/Fiscal Subcommittee meeting on August 19--20, 1991. Table 1 shows the FY 1993 milestones; Table 2 shows estimated costs. The subsequent work scope descriptions are based on the milestones. This document and the FY 1992 task plans will form the basis for a contract with Battelle and the Centers for Disease Control (CDC). The 2-year dose reconstruction contract is expected to begin in February 1992. This contract will replace the current arrangement, whereby the US Department of Energy directly funds the Pacific Northwest Laboratory to conduct dose reconstruction work. In late FY 1992, the FY 1993 task plans will be more fully developed with detailed technical approaches, data quality objectives, and budgeted labor hours. The task plans will be updated again in July 1993 to reflect any scope, milestone, or cost changes directed during the year by the TSP. 2 tabs.
Date: October 1, 1991
Creator: Shipler, D. B.
Partner: UNT Libraries Government Documents Department

Radiogenic neoplasia in thyroid and mammary clonogens

Description: We have developed rat thyroid and mammary clonogen transplantation systems for the study of radiogenic cancer induction at the target cell level in vivo. The epithelial cell populations of both glands contain small subpopulations of cells which are capable of giving rise to monoclonal glandular structures when transplanted and stimulated with appropriate hormones. During the end of the last grant year and the first half of the current grant year, we have completed analyses and summarized for publication: investigations on the relationship between grafted thyroid cell number and the rapidity and degree of reestablishment of the thyroid-hypothalamicpituitary axis in thyroidectomized rats maintained on a normal diet or an iodine deficient diet; studies of the persistence of, and the differentiation potential and functional characteristics of, the TSH- (thyrotropin-) responsive sub-population of clonogens during goitrogenesis, the plateau-phase of goiter growth, and goiter involution; studies of changes in the size of the clonogen sub-population during goitrogenesis, goiter involution and the response to goitrogen rechallenge; and the results of the large carcinogenesis experiment on the nature of the grafted thyroid cell number-dependent suppression of promotion/progression to neoplasia in grafts of radiation-initiated thyroid cells. We are testing new techniques for the culture, cytofluorescent analysis and characterization mammary epithelial cells and of clonogens in a parallel project, and plan to apply similar technology to the thyroid epithelial cells and clonogen population. Data from these studies will be used in the design of future carcinogenesis experiments on neoplastic initiation by high and low LET radiations and on cells interactions during the neoplastic process.
Date: May 31, 1991
Creator: Clifton, K.H.
Partner: UNT Libraries Government Documents Department

Radiogenic neoplasia in thyroid and mammary clonogens. Progress report, January 1, 1991--December 31, 1991

Description: We have developed rat thyroid and mammary clonogen transplantation systems for the study of radiogenic cancer induction at the target cell level in vivo. The epithelial cell populations of both glands contain small subpopulations of cells which are capable of giving rise to monoclonal glandular structures when transplanted and stimulated with appropriate hormones. During the end of the last grant year and the first half of the current grant year, we have completed analyses and summarized for publication: investigations on the relationship between grafted thyroid cell number and the rapidity and degree of reestablishment of the thyroid-hypothalamicpituitary axis in thyroidectomized rats maintained on a normal diet or an iodine deficient diet; studies of the persistence of, and the differentiation potential and functional characteristics of, the TSH- (thyrotropin-) responsive sub-population of clonogens during goitrogenesis, the plateau-phase of goiter growth, and goiter involution; studies of changes in the size of the clonogen sub-population during goitrogenesis, goiter involution and the response to goitrogen rechallenge; and the results of the large carcinogenesis experiment on the nature of the grafted thyroid cell number-dependent suppression of promotion/progression to neoplasia in grafts of radiation-initiated thyroid cells. We are testing new techniques for the culture, cytofluorescent analysis and characterization mammary epithelial cells and of clonogens in a parallel project, and plan to apply similar technology to the thyroid epithelial cells and clonogen population. Data from these studies will be used in the design of future carcinogenesis experiments on neoplastic initiation by high and low LET radiations and on cells interactions during the neoplastic process.
Date: May 31, 1991
Creator: Clifton, K. H.
Partner: UNT Libraries Government Documents Department