Dose assessment

The ratio of plutonium isotopes to 241 Am is often reported in monitoring studies as it is an important tool in dose assessment by enabling a determination of plutonium concentrations. 243Am is produced directly by the capture of two neutrons by 241 Am. The parent of241 Am is 241Pu, which constitutes about 12% of the 1% content of a typical spent fuel rod from a nuclear reactor, has a half-life of 14 years. Separation of... 

Byrom J, Robinson C, Simmonds JR et al. 1995. Food consumption rates for use in generalized radiological dose assessments. J Radiol Prot 15 (4) 335-341. 

Robison WL, Noshkin VE, Conrado CL, et al. 1997a. The northern Marshall Island radiological survey Data and dose assessment. Health Phys 73(l) 37-48. 

Robison WL, Bogen KT, Conrado CL. 1997b. An updated dose assessment for resettlement options at Bikini Atoll-a U.S. nuclear test site. Health Phys 73(1) 100-114. 

Dose Assessment—An estimate of the radiation dose to an individual or a population group usually by means of predictive modeling techniques, sometimes supplemented by the results of measurement. 

Egan, M.J. and W. Nixon, A Model of Aerosol Deposition in the Lung for Use in Inhalation Dose Assessments, Radiat. Prot. Dosim. 11 5-17 (1985)... 

Individual dose assessment requires radiological data on all external and internal sources contributing to occupational and non-occupational radiation exposure (Steinhausler and Pohl, 1983). This is of particular importance in the case of low level Rn-d exposure, as man is always exposed to Rn-d at varying levels through all stages of life, e.g. at school, home or work. The resulting lifetime risk from this chronic exposure is influenced by the latent... 

Goans, R.E., Holloway, E.C., Berger, M.E., and Ricks, R.C., Early dose assessment following severe radiation accidents, Health Physics, 72, 513, 1997. 

PM concentration fields coming from air quality models are estimations of outdoor microenvironments that combined with gridded population and microenvironments information can be used for exposure modelling and estimation of doses and health effects, integrating the source to dose assessment chain (recall Fig. 1). 

The exposure scenario described in the previous example of domestic uranium mill tailings was used to classify the high-radium residues. The risk and dose assessments indicated a probability of radiation-induced cancer incidence of about 0.6, potential doses in excess of 10 Sv, and a risk index between 50 and 100. Thus, these residues would be classified as high-hazard waste, even under conditions of perpetual institutional control over near-surface disposal sites, and they would require some form of greater confinement disposal well below the ground surface. This conclusion is consistent with recommendations for disposition of these residues (NAS/ NRC, 1995b). 

Egan, M.J. Nixon, W. (1985) A model of aerosol deposition in the lung for use in inhalation dose assessments. Radiation Protection Dosimetry, 11, 5-17. 

In principle, the outputs from variability and uncertainty analysis are used to quantify the nature of the variability in the predicted distribution of the exposures and the uncertainties associated with different percentiles of the predicted population exposure or risk estimates. The combined sensitivity and uncertainty are also used in a two-dimensional probabilistic exposure or dose assessment, in order to determine either the uncertainty about exposure (or... 

Layton DW (1993) Metabolically consistent breathing rates for use in dose assessments. Health Physics, 64(1) 23-36. 

Another study using the same dose assessed pharmacokinetic parameters in 15 healthy volunteers and 14 patients with an acute exacerbation of viral hepatitis. None had significantly altered prothrombin times, but all had significantly raised transaminase levels. Similar alterations in pharmacokinetics were observed. Acute viral hepatitis increased the half-life from 3.37 hours to 6.99 hours (p<0.001) (range ... 

THERdbASE contains two major modules, namely a Database Module and a Model Base Module. The Database Module relates information from exposure, dose and risk-related data files, and contains information about the following population distributions, location/activity patterns, food-consumption patterns, agent properties, agent sources (use patterns), environmental agent concentrations, food contamination, physiological parameters, risk parameters and miscellaneous data files. The Model Base Module provides access to exposure dose and risk-related models. The specific models included with the software are as follows Model 101, subsetting activity pattern data Model 102, location patterns (simulated) Model 103, source (time application) Model 104, source (instantaneous application) Model 105, indoor air (two zones) Model 106, indoor air (n zones) Model 107, inhalation exposure (BEAM) Model 108, inhalation exposure (multiple chemicals) Model 109, dermal dose (film thickness) Model 110, dose scenario (inhalation/dermal) Model 201, soil exposure (dose assessment). 

CBC and differential STAT, followed by Radiation dose assessment establish absolute lymphocyte counts every 6 hrs. for baseline (initial counts) tor comparison with 48 hrs. if whole-body irradiation possible. later counts to assess degree ot injury. Draw blood from noncontaminated area, cover puncture site afterward. 

Kim, C.S., Ross, I.A., Sberg, J.A., and Preston, E. 1998. Quantitative low-dose assessment of seafood toxin, domoic acid, in the rat brain application of physiologically-based pharmacokinetic (PBPK) modeling. Environ Toxicol Pharmacol 6, 49-58. 

Dehos A, Hinz G, Schwarz ER. 1986. Changes in number and function of the lyphocyte populations as a biological indicator for ionizing radiation. In Biological indicators for radiation dose assessment. Munchen MMV Medizin Verlag, 298-301. 

Because there are so many factors involved in establishing dose pathways and which may be the critical pathway, various dose assessment computer based models have been developed. These models are also used to calculate the dose per unit release of a specified radionuclide for various pathways. The Release Upper Bound, RUB can be evaluated using a dose assessment model. This is done by varying the source term used such that the resulting dose equals the dose constraint or limit. The various exposure scenarios and pathways are also chosen for importance. 

In the work by Dalgamo and McClymont, 1989, materials were sought which could be used as accident dosimeters, i.e. solid, probably organic substances found on or about an accident victim and which could be used with ESR spectroscopy to give a rapid and reliable dose assessment. 

Later Stage Day 14 + Air sampling daily weekly to assess eventual repercussions. Sampling and analysis of different important foodstuffs for gamma, alpha and beta emitters. Modelling for dose assessment. 

The types and distribution of oral diseases observed in the residents of contaminated areas were the same as those of the residents of uncontaminated areas. Projects supported by the European Commission (EC) The EC supported many scientific research projects on Chernobyl s consequences. The results were summarized at the First International Conference of the European Union, Belarus, the Russian Federation and the Ukraine on the Consequences of the Chernobyl Accident, held in Minsk, on 18-22 March 1996. The projects produced valuable information that can be used for future emergency planning, dose assessment and environmental remediation as well as in the treatment of highly exposed individuals and in screening for thyroid cancer in children. 

The Marshall Islands Dose Assessment and Radioecology Project has been in existence at Lawrence Livermore National Laboratory (LLNL) since 1973. It was a program of the Health and Ecological Assessment Division (HEA), in the Environmental Programs Directorate at LLNL. The primary purpose of this program was to assess the radiological conditions in the Marshall Islands. 

Contamination levels assumed in dose assessment (IAEA Yearbook, 1995)... 

Robinson, W.L. et al.. The Northern Marshall Islands Radiological Survey Data and Dose Assessments. Health Phys., 73 (1) (1997) 37 8. 

Robinson, W.L., Phillips, W.A. and Colsher, C.S., Dose Assessment at Bikini Atoll, Rep. UCRL-51879, Part 5, Lawrence Livermore National Laboratory, Livermore, CA (1977). 

Goans, RE, Holloweay, EC, Berger, ME, Ricks, RCF. Early Dose Assessment in Criticality Accidents. Health Physics, 81(4) 446 49, 2001... 

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