Whole-body dose

The Leggett (1992) model was developed to predict tissue doses and whole-body dose to people who may be exposed to americium. The model is considered an updated version of the ICRP (1989) model for americium, which has been used to establish risk-based limits of intake of241 Am (ICRP 1989). The Leggett (1992) and ICRP (1989) models predict similar long-term average doses of americium to the liver and skeleton for an injection exposure and would be expected to predict similar radiation risks and risk-based intake limits (Leggett 1992). Descriptions of applications of the Leggett (1992) model in risk assessment have not been reported. 

The USTUR (1994) model was developed to predict tissue doses and whole-body dose to people who may be exposed to americium. The model has been used to calculate Annual Limits of Intake (ALIs) for 241Am, and yielded similar, but lower limits than those estimated using the ICRP model (1989). 

Survival time and associated mode of death of selected mammals after whole-body doses of gamma radiation... 

Figure 32.9 Survival time and associated mode of death of selected mammals after whole-body doses of gamma radiation. (Modified from Hobbs, C.H. and R.O. McClellan. 1986. Toxic effects of radiation and radioactive materials. Pages 669-705 in C.D. Klaassen, M.O. Amdur, and J. Doull [eds.]. Casarett and Doull s Toxicology. Third Edition. Macmillan, New York United Nations Scientific Committee on the Effects of Atomic Radiation [UNSCEAR]. 1988. Sources, Effects and Risks of Ionizing Radiation. United Nations, New York. 647 pp.)...

Total beta and gamma radiation Total annual whole-body dose equivalent, or dose 3... 

Individual - operational guide for "suitable sample of population when Individual whole body doses are not known... 

Total annual whole-body dose equivalent, or dose to any internal organ, <0.04 mSv (<0.004 rem), based on individual consumption of 2 L daily of drinking water from a groundwater source... 

K is a (3 -emitting nuclide that is the predominant radioactive component of normal foods and human tissue. Due to the 1460-keV 7 ray that accompanies the (3 decay, it is also an important source of background radiation detected by 7-ray spectrometers. The natural concentration in the body contributes about 17 mrem/y to the whole body dose. The specific activity of 40K is approximately 855 pCi/g potassium. Despite the high specific activity of 87Rb of 2400 pCi/g, the low abundance of rubidium in nature makes its contribution to the overall radioactivity of the environment small. 

The ministry took account of the level of the European Community (370 Bq/kg for milk and infant food and 600 Bq/kg for general food) and that of the USA (10.000 pCi/kg, 370 Bq/kg) and set up the Japanese interim standard level of 370 Bq/kg) If radioactive contamination of imported foods was over the standard level, the foods were requested to be reshipped as products in violation of the Food Sanitation Law of Japan. Although the level was reviewed afterwards, the level was still suitable for products imported from European countries, even after amendment of the law of Japan in which the annual whole body dose limit of 500 mrem was altered to 100 mrem (=1 mSv) in 1988 (on the basis of the recommendation of ICRP Publ. 26, in 1985), because the real foods imported from European countries were estimated to account for 5% of all imported foods which were 35% of all food intake in Japan. 

There is no evidence to date of any increase in the incidence of any malignancies other than thyroid carcinoma or of any hereditary effects attributable to radiation exposure caused by the Chernobyl accident. This conclusion, surprising for some observers, is in accordance with the relatively small whole body doses incurred by the populations exposed to the radioactive material released. The lifetime doses expected to be incurred by these populations are also small. In fact, the risks of radiation-induced malignancies and hereditary effects are extremely small at low radiation doses and, as the normal incidences of these effects in people are relatively high, it is not surprising that no effects could be detected. 

Kjellstrom T. Critical organs, critical concentrations, and whole body dose-response relationships, in Cadmium and health a toxicological and epidemiological appraisal. Volume II effects and response. Friberg L, Elinder C-G, Kjellstrom T, Nordberg GF (editors). CRC Press, Boca Raton, Florida 1986 p. 231-246. 

Clinicians can crudely estimate the absorbed dose from the clinical presentation and peripheral leukocyte counts. The interval from exposure to emesis onset decreases with increasing doses. If the interval is less than 4h, the effective whole body dose is probably at least 3.5 Gy. If the interval is under Ih, the patient probably received a dose of 6.5 Gy or more. Patients with this level or exposure are likely to experience a complicated medical course with a high fatality rate (5). 

The expectant mother may be experiencing ARS in this range, depending on her whole-body dose... 

Effective dose (HE). An estimated whole-body dose weighted for radiosensitivity of each organ. It is calculated by summing the product of dose equivalent (Hr) and tissue radiosensitivity (Wt) of each organ, )T //T r Wt. 

C. Erythema. A person who received a whole-body dose of more than 1000-2000 cGy will develop erythema within the first day postexposure. This is also true for those who received comparable doses to local body regions. In this case, the erythema is restricted to the affected area. With doses lower but still in the potentially fatal range (200 cGy or more), erythema is less frequently seen. 

The effective (whole body) dose equivalent for pertechnetate " Tc is 0.013 mSv/MBq (International Commission on Radiological Protection 1987). The effective dose in adults (70 kg) resulting from 75 MBq of intravenously injected Tc-pertechnetate for thyroid scintigraphy is approximately 1 mSv. The absorbed radiation dose to the thyroid (without a blocking agent) resulting from an intravenous injection of 75 MBq of 99mTc-pertechnetate corresponds to 1.7 mCy. 

Lung, liver, and the bladder wall are the most exposed organs. The effective (whole body) dose equivalent is 0.012 mSv/MBq (International Commission on Radiological Protection 1987). Elimination from the lung is assumed with half-times of 6 h (0.85) and 3 days (0.15). The liver takes up a fraction of 0.25, with an uptake half-time of 6 h and an elimination half-time of 5 days. Radionuclide released from the lung is primarily excreted by the kidneys (Malone et al. 1983). 

The effective (whole body) dose resulting from bilateral venography injecting a total of approximately 185 MBq (5 mCi) of Tc-MAA was estimated as 1.35 mSv (Malone et al. 1983). 

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