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Twenty-year review of medical findings in a Marshallese population accidentally exposed to radioactive fallout

Description: A summary is presented of results of medical examinations of inhabitants of the Marshall Islands during the 20-year period following the exposure of Rongelap people to radioactive fallout in 1954. The initial effect observed was $beta$ burns of the skin of some individuals. Few significant findings were observed during the subsequent 9-year period, although an increase in miscarriages and stillbirths among the exposed women was noted. In 1963 some thyroid abnormalities and growth retardation of some children were noted. (177 references). (CH)
Date: January 1, 1975
Creator: Conard, R.A.
Partner: UNT Libraries Government Documents Department

Position Paper on Practicable Performance Criteria for the Removal Efficiency of Volatile Radionuclides

Description: As a result of fuel reprocessing, volatile radionuclides may be released from the facility stack if no processes are put in place to remove them. The radionuclides that are of concern in this document are 3H, 14C, 85Kr, and 129I. The question we attempted to answer is how efficient must this removal process be for each of these radionuclides? To answer this question, we examined the three regulations that may impact the degree to which these radionuclides must be reduced before process gases can be released from the facility. These regulations are 40 CFR 61 (EPA 2010a), 40 CFR 190(EPA 2010b), and 10 CFR 20 (NRC 2012). These regulations apply to the total radionuclide release and to a particular organ - the thyroid. Because these doses can be divided amongst all the radionuclides in different ways and even within the four radionuclides in question, we provided several cases. We first looked at the inventories for these radionuclides for three fuel types (PWR UOX, PWR MOX, and AHTGR), several burn-up values, and time out of reactor extending to 200 y. We calculated doses to the maximum exposed individual (MEI) with the EPA code CAP-88 (Rosnick 1992). Finally, we looked at two dose cases. Allocating all of the allowable dose to be used by the volatile radionuclides is one case, but, perhaps, unrealistic. In lieu of this, we arbitrarily selected a value of 10% of the allowable dose to be assigned to the volatile radionuclides. We calculated the required decontamination factors (DFs) for both of these cases, including the case for the thyroid dose for which 14C and 129I were the main contributors. With respect to 129I doses, we found that the highest dose was calculated with iodine as a fine particulate. The dose scaled as the fraction of the total 129I ...
Date: March 1, 2012
Creator: Jubin, R. T.; Soelberg, N. & Strachan, D. M.
Partner: UNT Libraries Government Documents Department

Calibration of the Accuscan II In Vivo System for I-125 Thyroid Counting

Description: This report describes the March 2011 calibration of the Accuscan II HpGe In Vivo system for I-125 thyroid counting. The source used for the calibration was a DOE manufactured Am-241/Eu-152 source contained in a 22 ml vial BEA Am-241/Eu-152 RMC II-1 with energies from 26 keV to 344 keV. The center of the detector housing was positioned 64 inches from the vault floor. This position places the approximate center line of the detector housing at the center line of the source in the phantom thyroid tube. The energy and efficiency calibration were performed using an RMC II phantom (Appendix J). Performance testing was conducted using source BEA Am-241/Eu-152 RMC II-1 and Validation testing was performed using an I-125 source in a 30 ml vial (I-125 BEA Thyroid 002) and an ANSI N44.3 phantom (Appendix I). This report includes an overview introduction and records for the energy/FWHM and efficiency calibration including performance verification and validation counting. The Accuscan II system was successfully calibrated for counting the thyroid for I-125 and verified in accordance with ANSI/HPS N13.30-1996 criteria.
Date: July 1, 2011
Creator: Perry, Ovard R. & Georgeson, David L.
Partner: UNT Libraries Government Documents Department

Calibration of the Accuscan II In Vivo System for I-131 Thyroid Counting

Description: This report describes the March 2011 calibration of the Accuscan II HpGe In Vivo system for I-131 thyroid counting. The source used for the calibration was an Analytics mixed gamma source 82834-121 distributed in an epoxy matrix in a Wheaton Liquid Scintillation Vial with energies from 88.0 keV to 1836.1 keV. The center of the detectors was position 64-feet from the vault floor. This position places the approximate center line of the detectors at the center line of the source in the thyroid tube. The calibration was performed using an RMC II phantom (Appendix J). Validation testing was performed using a Ba-133 source and an ANSI N44.3 Phantom (Appendix I). This report includes an overview introduction and records for the energy/FWHM and efficiency calibrations including verification counting. The Accuscan II system was successfully calibrated for counting the thyroid for I-131 and verified in accordance with ANSI/HPS N13.30-1996 criteria.
Date: July 1, 2011
Creator: Perry, Orval R. & Georgeson, David L.
Partner: UNT Libraries Government Documents Department

Transmission scanning II

Description: From nuclear science symposium; San Francisco, California, USA (14 Nov 1973). Work has been continued on the development of techniques for imaging spatial elemental distributions by means of differential absorption about the K- absorption edge of the particular element Z. A method to correct for spurious effects due to differential absorption in overlying absorber is described. Initial clinical studies of thyroid iodine images on patierts are presented. Application of absorption edge transmission scanning to measurements of Ca cortent in thin in-vitro samples of rat bone is also discussed. An x-ray source with a broad energy spectrum was used. (CH)
Date: January 1, 1973
Creator: Alberi, J.L.; Kraner, H.W.; Bradley-Moore, P. & Atkins, H.L.
Partner: UNT Libraries Government Documents Department

Comparative evaluation of $sup 123$I and /sup 99m/Tc for thyroid studies

Description: A comparative study of the metabolism of /sup 129/I and /sup 99m/Tc in the thyroid was made. Thirty-minute uptake curves were determined for 26 patients and comparison images were obtained at 30 minutes With /sup 99m/Tc and at 30 minutes and 24 hours with /sup 123/I. Both radionuclides can be used to advantage in assessing thyroid function and anatomy. The reasonable cost of /sup 123/I adds to its clinical value. (HLW)
Date: January 1, 1973
Creator: Atkins, H.L.; Ansari, A.N.; Bradley-Moore, P.R.; Lambrecht, R. & Wolf, A.
Partner: UNT Libraries Government Documents Department

THYROID METABOLISM IN CHILDREN AND ADULTS USING VERY SMALL (NANOCURIE) DOSES OF IODINE$sup 125$ AND IODINE$sup 13$$sup 1$

Description: A new technique for measuring the radioiodine content of the human thyroid in vivo with nanocurie amounts of I/sup 131/ and I/sup 125/ is described. The technique gives a measure of the thickness of neck tissue over the thyroid; values of 0.4 and 2.0 cm have been found in the subjects studied thus far. Results on 6 normal adults show uptake at 7 days after oral ingestion varies between 15 and 29%, with biological half times between 27 days and infinity. Results on 8 normal children (ages 4 to 10 yr) show little or no difference from adults as far as the data extend (15 days post oral ingestion). Uptakes vary between 9.5 and 27%, and biological half times are long compared to the 8-day physical haif life. (auth)
Date: January 1, 1963
Creator: Van Dilla, M.A. & Fulwyler, M.J.
Partner: UNT Libraries Government Documents Department

Radioecology of iodine-129: an interim report

Description: Radioactive isotopes of iodine are Produced during nuclear fission in reactors and in weapons tests and to a limited extent in nature. Because of its extremely long half-life (1.6 x 10/sup 7/ yr) 1291 has the potential for accumulation in the environment from longterm, chronic releases from nuclear facilities. Possible problems associated with such an accumulation, including transfer of the /sup 129/I through the biosphere and resultant radiation doses to man and other organisms are discussed. (70 references) (CR)
Date: September 1, 1973
Creator: Soldat, J.K.; Brauer, F.P.; Cline, J.F.; Fager, J.E.; Klepper, B.; Rickard, W.H. et al.
Partner: UNT Libraries Government Documents Department

Natural iodine and iodine-129 in mammalian thyroids and environmental samples taken from locations in the United States

Description: From symposium on enviromnental surveillance around nuclear installation; Warsaw, Poland (5 Nov 1973). Bovine and other mammalian thyroids, air, precipitation, water, grass, and milk samples from selected locations were analyzed for their natural iodine and iodine-129 content. Particle filters and activated charcoal beds were used to collect the particulate and gaseous iodine fractions from the air. Anion exchange was used for the separation of iodine from liquid samples. Cumbustion methods were used for iodine separation from solid samples, anlon exchange resins, and air filters. Iodine-129 and natural iodine concentrations were determined by neutron activation analysis with a detection limit of about 10/sup 8/ atoms of iodine-129 per sample. Analytical results of both /sup 129/I concentrations and ratios of atoms of /sup 129/I per atom of /sup 127/I for these samples are summarized. The small radiation doses to human thyroids projected from these low /sup 129/I concentrations are also discussed. (auth)
Date: January 1, 1973
Creator: Brauer, F.P.; Soldat, J.K.; Tenny, H. & Strebin, R.S. Jr.
Partner: UNT Libraries Government Documents Department