8 research outputs found
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Detection of internally deposited actinides. Part II. Statistical techniques and risk analysis
Since a considerable number of workers at Oak Ridge National Laboratory work with compounds of the transuranic elements, computer techniques have been developed to evaluate phoswich spectra in order to determine lung burdens following accidental inhalation of Pu, Am, Cm or other isotopes. Two unfolding methods which have been found useful in the analysis of such cases are presented and discussed. These techniques have been used successfully to detect low levels of Pu, Am, Cm, U, Sr, and Gd in contaminated workers; but because of the current importance of Pu, emphasis is placed on detection of that isotope in the presence of Am and natural human background. In the health physics tradition of emphasizing benefit vs. risk, we also analyze uncertainties inherent in external counting of the actinides from the viewpoint of statistical risk analysis and derive decision criteria which are useful in determining whether various radioactive species have, in fact, been detected. These criteria are somewhat different from those encountered using traditional counting statistics and derive from the realization that some errors will always be made in scanning large numbers of radiation workers. The optimum decision strategy for the determination of lung burden is, therefore, one which minimizes the long-term risk of error. The usefulness of this approach to whole body counting will be discussed and analyzed. (auth
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Detection of internally deposited actinides. Part III. Recent background studies at ORNL
It has been apparent from accumulated data at ORNL that the low-energy (less than 100 keV) phoswich background spectrum in the iron-shielded counting facility has components, possibly including a line below 15 keV, whose magnitudes show considerable variability. We have used a planar intrinsic Ge detector designed especially for measuring low-energy photons for background study as part of an evaluation of such a device for in vivo Pu measurement. The spectrum that was observed consisted of a continuum upon which were superimposed discrete lines including a strong line at 10.35 keV in addition to the well-known lines from Pb X rays. Detectable also were X rays that corresponded to K-lines of several of the products of the naturally occurring radioactive decay series. Background spectra are presented and the implications of their variability are discussed. (auth
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Evaluation of two cases of Cm inhalation
Chest and systemic burdens were estimated for two employees who inhaled largely soluble compounds of Cm. Chest burdens by whole-body counting were: Case A, 28 nCi; Case B, 34 nCi. The urinary excretion of the employees appeared to conform to a series of exponentials similar to those reported for blood and whole-body retention of Am in baboons. Accordingly, retention functions composed of a series of exponentials having 4, 12 to 17, and 72 day half-times were derived from urinary excretion and used to calculate body burdens, Case A, 7 nCi and Case B, 16 nCi. Cumulative fecal excretion by Case B was some 20 times that by Case A (63 nCi vs. 3.2) probably due to differences in deposition in the respiratory tract. Calculated organ doses for the first year were approximately 20 percent of recommended maxima. (auth
BiodosEPR-2006 Meeting: Acute dosimetry consensus committee recommendations on biodosimetry applications in events involving uses of radiation by terrorists and radiation accidents
In the aftermath of a radiological terrorism incident or mass-casualty radiation accident, first responders and receivers require prior guidance and pre-positioned resources for assessment, triage and medical management of affected individuals [NCRP, 2005. Key elements of preparing emergency responders for nuclear and radiological terrorism. NCRP Commentary No. 19, Bethesda, Maryland, USA]. Several recent articles [Dainiak, N., Waselenko, J.K., Armitage, J.O., MacVittie, T.J., Farese, A.M., 2003. The hematologist and radiation casualties. Hematology (Am. Soc. Hematol. Educ. Program) 473-496; Waselenko, J.K., MacVittie, T.J., Blakely, W.F., Pesik, N., Wiley, A.L., Dickerson, W.E., Tsu, H., Confer, D.L., Coleman, C.N., Seed, T., Lowry, P., Armitage, J.O., Dainiak, N., Strategic National Stockpile Radiation Working Group, 2004. Medical management of the acute radiation syndrome: recommendations of the Strategic National Stockpile Radiation Working Group. Ann. Intern. Med. 140(12), 1037-1051; Blakely, W.F., Salter, C.A., Prasanna, P.G., 2005. Early-response biological dosimetry-recommended countermeasure enhancements for mass-casualty radiological incidents and terrorism. Health Phys. 89(5), 494-504; Goans, R.E., Waselenko, J.K., 2005. Medical management of radiation casualties. Health Phys. 89(5), 505-512; Swartz, H.M., Iwasaki, A., Walczak, T., Demidenko, E., Salikhov, I., Lesniewski, P., Starewicz, P., Schauer, D., Romanyukha, A., 2005. Measurements of clinically significant doses of ionizing radiation using non-invasive in vivo EPR spectroscopy of teeth in situ. Appl. Radiat. Isot. 62, 293-299; Weisdorf, D., Chao, N., Waselenko, J.K., Dainiak, N., Armitage, J.O., McNiece, I., Confer, D., 2006. Acute radiation injury: contingency planning for triage, supportive care, and transplantation. Biol. Blood Marrow Transplant. 12(6), 672-682], national [National Council of Radiation Protection and Measurements (NCRP), 1994. Management of persons accidentally contaminated with radionuclides. NCRP Report No. 65, Bethesda, Maryland, USA; NCRP, 2001. Management of terrorist events involving radioactive material. NCRP Report No. 138, Bethesda, Maryland, USA; NCRP, 2005. Key elements of preparing emergency responders for nuclear and radiological terrorism. NCRP Commentary No. 19, Bethesda, Maryland, USA] and international [IAEA, 2005. Generic procedures for medical response during a nuclear or radiological emergency. EPR-Medical 2005, IAEA, Vienna, Austria] agencies have reviewed strategies for acute-phase biodosimetry. Consensus biodosimetric guidelines include: (a) clinical signs and symptoms, including peripheral blood counts, time to onset of nausea and vomiting and presence of impaired cognition and neurological deficits, (b) radioactivity assessment, (c) personal and area dosimetry, (d) cytogenetics, (e) in vivo electron paramagnetic resonance (EPR) and (f) other dosimetry approaches (i.e. blood protein assays, etc.). Emerging biodosimetric technologies may further refine triage and dose assessment strategies. However, guidance is needed regarding which biodosimetry techniques are most useful for different radiological scenarios and consensus protocols must be developed. The Local Organizing Committee for the Second International Conference on Biodosimetry and Seventh International Symposium on EPR Dosimetry and Applications (BiodosEPR-2006 Meeting) convened an Acute Dosimetry Consensus Committee composed of national and international experts to: (a) review the current literature for biodosimetry applications for acute-phase applications in radiological emergencies, (b) describe the strengths and weaknesses of each technique, (c) provide recommendations for the use of biodosimetry assays for selected defined radiation scenarios, and (d) develop protocols to apply these recommended biological dosimetry techniques with currently available supplies and equipment for first responders. The Acute Dosimetry Consensus Committee developed recommendations for use of a prioritized multiple-assay biodosimetric-based strategy, concluding that no single assay is sufficiently robust to address all of the potential radiation scenarios including management of mass casualties and diagnosis for early medical treatment. These recommendations may be used by first responders/first receivers that span time-windows of (i.e. 0-5 days) after the radiological incident for three radiological scenarios including: (a) radiation exposure device (RED), (b) radiological dispersal device (RDD), and (c) an improvised (or otherwise acquired) nuclear device (IND). Consensus protocols for various bioassays (i.e. signs and symptoms recording, bioassay sampling for radioactivity analysis, nail-clipping sampling for EPR analysis and blood collection for hematology, cytogenetics, and blood chemistry analyses) are presented as Appendix materials. As stated in NCRP Commentary No. 19 [NCRP, 2005. Key elements of preparing emergency responders for nuclear and radiological terrorism. NCRP Commentary No. 19, Bethesda, Maryland, USA], multi-parameter triage (i.e. time to vomiting, lymphocyte kinetics, and other biodosimetry indicators) offers the current best strategy for early assessment of absorbed dose. © 2007 Elsevier Ltd. All rights reserved
BiodosEPR-2006 Meeting: Acute dosimetry consensus committee recommendations on biodosimetry applications in events involving uses of radiation by terrorists and radiation accidents
In the aftermath of a radiological terrorism incident or mass-casualty radiation accident, first responders and receivers require prior guidance and pre-positioned resources for assessment, triage and medical management of affected individuals [NCRP, 2005. Key elements of preparing emergency responders for nuclear and radiological terrorism. NCRP Commentary No. 19, Bethesda, Maryland, USA]. Several recent articles [Dainiak, N., Waselenko, J.K., Armitage, J.O., MacVittie, T.J., Farese, A.M., 2003. The hematologist and radiation casualties. Hematology (Am. Soc. Hematol. Educ. Program) 473-496; Waselenko, J.K., MacVittie, T.J., Blakely, W.F., Pesik, N., Wiley, A.L., Dickerson, W.E., Tsu, H., Confer, D.L., Coleman, C.N., Seed, T., Lowry, P., Armitage, J.O., Dainiak, N., Strategic National Stockpile Radiation Working Group, 2004. Medical management of the acute radiation syndrome: recommendations of the Strategic National Stockpile Radiation Working Group. Ann. Intern. Med. 140(12), 1037-1051; Blakely, W.F., Salter, C.A., Prasanna, P.G., 2005. Early-response biological dosimetry-recommended countermeasure enhancements for mass-casualty radiological incidents and terrorism. Health Phys. 89(5), 494-504; Goans, R.E., Waselenko, J.K., 2005. Medical management of radiation casualties. Health Phys. 89(5), 505-512; Swartz, H.M., Iwasaki, A., Walczak, T., Demidenko, E., Salikhov, I., Lesniewski, P., Starewicz, P., Schauer, D., Romanyukha, A., 2005. Measurements of clinically significant doses of ionizing radiation using non-invasive in vivo EPR spectroscopy of teeth in situ. Appl. Radiat. Isot. 62, 293-299; Weisdorf, D., Chao, N., Waselenko, J.K., Dainiak, N., Armitage, J.O., McNiece, I., Confer, D., 2006. Acute radiation injury: contingency planning for triage, supportive care, and transplantation. Biol. Blood Marrow Transplant. 12(6), 672-682], national [National Council of Radiation Protection and Measurements (NCRP), 1994. Management of persons accidentally contaminated with radionuclides. NCRP Report No. 65, Bethesda, Maryland, USA; NCRP, 2001. Management of terrorist events involving radioactive material. NCRP Report No. 138, Bethesda, Maryland, USA; NCRP, 2005. Key elements of preparing emergency responders for nuclear and radiological terrorism. NCRP Commentary No. 19, Bethesda, Maryland, USA] and international [IAEA, 2005. Generic procedures for medical response during a nuclear or radiological emergency. EPR-Medical 2005, IAEA, Vienna, Austria] agencies have reviewed strategies for acute-phase biodosimetry. Consensus biodosimetric guidelines include: (a) clinical signs and symptoms, including peripheral blood counts, time to onset of nausea and vomiting and presence of impaired cognition and neurological deficits, (b) radioactivity assessment, (c) personal and area dosimetry, (d) cytogenetics, (e) in vivo electron paramagnetic resonance (EPR) and (f) other dosimetry approaches (i.e. blood protein assays, etc.). Emerging biodosimetric technologies may further refine triage and dose assessment strategies. However, guidance is needed regarding which biodosimetry techniques are most useful for different radiological scenarios and consensus protocols must be developed. The Local Organizing Committee for the Second International Conference on Biodosimetry and Seventh International Symposium on EPR Dosimetry and Applications (BiodosEPR-2006 Meeting) convened an Acute Dosimetry Consensus Committee composed of national and international experts to: (a) review the current literature for biodosimetry applications for acute-phase applications in radiological emergencies, (b) describe the strengths and weaknesses of each technique, (c) provide recommendations for the use of biodosimetry assays for selected defined radiation scenarios, and (d) develop protocols to apply these recommended biological dosimetry techniques with currently available supplies and equipment for first responders. The Acute Dosimetry Consensus Committee developed recommendations for use of a prioritized multiple-assay biodosimetric-based strategy, concluding that no single assay is sufficiently robust to address all of the potential radiation scenarios including management of mass casualties and diagnosis for early medical treatment. These recommendations may be used by first responders/first receivers that span time-windows of (i.e. 0-5 days) after the radiological incident for three radiological scenarios including: (a) radiation exposure device (RED), (b) radiological dispersal device (RDD), and (c) an improvised (or otherwise acquired) nuclear device (IND). Consensus protocols for various bioassays (i.e. signs and symptoms recording, bioassay sampling for radioactivity analysis, nail-clipping sampling for EPR analysis and blood collection for hematology, cytogenetics, and blood chemistry analyses) are presented as Appendix materials. As stated in NCRP Commentary No. 19 [NCRP, 2005. Key elements of preparing emergency responders for nuclear and radiological terrorism. NCRP Commentary No. 19, Bethesda, Maryland, USA], multi-parameter triage (i.e. time to vomiting, lymphocyte kinetics, and other biodosimetry indicators) offers the current best strategy for early assessment of absorbed dose