Whole-body dosimetry

The use of the patch method, although yielding some good data about exposure over the years, started to fade quickly when whole-body dosimeter methodology was introduced. The whole-body dosimetry method gave more precise whole-body exposure values from one worker to another since the whole garment was extracted and analyzed, and one did not have to extrapolate exposure to large areas of the body. ° ... 

Methods for measuring worker exposure using simultaneous biological monitoring and whole-body dosimetry... 

This study was conducted to evaluate and compare ADD determined using whole-body dosimetry with results of two situational exposure studies conducted following use of a flea fogger under natural conditions. Chlorpy-rifos was selected due to its general availability as a fogger for indoor flea control. Chlorpyrifos is poorly absorbed by the dermal route and readily cleared from the body in urine (Nolan et al., 1984). Trichloropyridinol was measured in 24-hr urine specimens of the volunteers and was converted to chlorpyrifos equivalents as a measure of absorbed dose. The study provided an opportunity to determine the relationship between intensive, high-contact dosimetry studies and the amounts of chlorpyrifos absorbed by two sets of adults who re-entered fogger-treated homes. 

Table 3 Estimates of Human Exposure Derived from Whole-Body Dosimetry, Biomonitoring, and Routine Use of Pesticide Fogger...

Epidemiological and Human Dosimetry Studies. Epidemiological studies of radiation dose typically involve estimates of exposure that are based on whole-body measurements of internally-deposited americium. A need remains for epidemiological data that can provide quantitative human dose-response information while supplying additional information on the health effects of exposure to ionizing radiation and americium in particular, for cases of known internal exposure. 

Krieger, R.I., Bernard, C.E., Dinoff, T.M., Fell, L., Osimitz, T. G., Ross, J.I., and Thongsinthusak, T. (2000) Biomonitoring and whole body cotton dosimetry to estimate potential human dermal exposure to semivolatile chemicals, /. Exposure Anal. Environ. Epidemiol., 10 50-57. 

In the early 1980s, the whole-body dosimeter (WBD) was introduced as a superior method for passive dermal dosimetry monitoring. A standard protocol was described by the World Health Organization (1982), and Abbott et al. (1987) described some additional options. Chester (1993) reported refinements that permitted exposure estimation by passive dermal dosimetry and biological monitoring simultaneously. 

Beaudouin R, Micallef S, Brochot C (2010) A stochastic whole-body physiologically based pharmacokinetic model to assess the impact of inter-individual variability on tissue dosimetry over the human lifespan. Regul Toxicol Pharmacol 57 103-116... 

Radioactive Drugs If the drug is a radioactive drug, sufficient data from animal or human studies to allow a reasonable calculation of radiation-absorbed dose to the whole body and critical organs upon administration to a human subject are to be submitted. Phase 1 studies of radioactive drugs must include studies that will obtain sufficient data for dosimetry calculations. 

Diagnosis. The diagnosis of radiation sickness is based primarily upon the clinical picture presented by the patient. A precise history of exposure may be very difficult to obtain. Dosimetry will not give adequate information to determine either the extent of radiation injury or the prognosis. Dosimeters cannot tell whether a radiation exposure is whole body or partial body. They do not tell what the dose rate of the exposure was. Finally, they cannot differentiate between single exposures and multiple exposures unless read at regular intervals. However, in the... 

Tissue distribution studies in pigmented Long-Evans rats to provide dosimetry to various tissues and organs are required to support human ADME with radiolabeled compound. Typically, these studies are limited to a single dose by the intended route of administration (PO, IV, etc.). The radioactivity levels in various tissues at different time points can be measured by quantitative whole-body autoradiography (QWBA) where sections of the... 

Effective dose—A dosimetry quantity useful for comparing the overall health effects of irradiation of the whole body effective dose is used to compare the overall health detriments of different radio nuclides in a given mix. 

At all stages of medical care, the treatment of highly contaminated individuals will require special facilities or isolated facilities with the specif procedures that limit the spread of contamination and disposal of contaminated waste. For the deteetion of radioaetive eontam-ination, radiation equipment should be available, such as specialized radiation monitoring instruments, whole body counter, and iodine thyroid counter. Usually a radiation protection officer or health physicist performs the measurements. For the purpose of dose reeonstraction, different instruments and methods can be used, such as electronic paramagnetic resonance (EPR) spectrometry and cytogenetic dosimetry. Because of this, collection of various tissues (blood, hair, and teeth) and clothes of exposed persons should be organized. Provisions (plastic bags, labels, etc.) should be made in advance. 

The purpose of the dose assessment for the public Uving in conditions of chronic (prolonged) radiation exposure is usually the justification of remedial actions that involve considerable expense associated with them. The doses of critical population groups should therefore be estimated on the basis of realistic, not screening, dosimetric models. To the extent possible, available data from environmental measurements and selective data from individual measurements, such as data from whole body counting for internal dosimetry and individual doses for external dosimetry, should be used to validate these models. 

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