A statistical model for reconstruction of historical internal doses for uranium workers.
Uranium workers are monitored for their internal doses mainly by urine measurements. During the years before the early nineties, urine samples were analysed using a fluorimetric system, and the lower limit of detection of the urine samples was relatively high, thus most of the urine measurements were recorded as below threshold. A model was developed for the reconstruction of doses to workers at uranium facilities during these years. The model is based on the assumption that the results of urine measurements are log-normally distributed and that a normalised log-normal distribution with a constant geometric standard deviation characterises the results distribution in all the uranium workplaces for workers throughout their occupational work. Therefore, the average of the urine results can be calculated from the general normalised distribution. The intake and dose can be evaluated from the reconstructed average urine concentration by assuming a constant chronic intake regime throughout the whole period of monitoring.
Kravchik
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T
Nuclear Research Center Negev, POB 9001, Beer-Sheva, Israel. tuvkra@zahav.net.il
German
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U
D001822:Body Burden; D003198:Computer Simulation; D006801:Humans; D015233:Models, Statistical; D009688:Nuclear Reactors / Q000706:statistics & numerical data*; D016273:Occupational Exposure / Q000032:analysis*; D011829:Radiation Dosage; D011834:Radiation Monitoring; D012062:Relative Biological Effectiveness; D014501:Uranium / Q000652:urine*
D014501:Uranium