Biokinetic modeling of uranium in man after injection and ingestion

Abstract

Uranium is a naturally occurring primordial radioactive element. Small amounts found in air, water, and food are regularly consumed and inhaled by humans. Even the military, medical, and industrial use of depleted uranium can affect humans. There is an appreciable retention of incorporated uranium in skeleton, kidneys, and liver, and a review of respective effective dose coefficients has been given by the International Commission on Radiological Protection (ICRP) in its "Publication 69"; however, data regarding retention in organs or tissues and rates of urinary and fecal excretion for different age groups are incomplete. Therefore, the present study provides retention data that have been calculated for uranium in all compartments and for urinary and fecal excretion, following acute and chronic injection and ingestion for six age groups. The calculations are based on the current ICRP biokinetic model for uranium, and the data can be plotted by using any mathematical software to obtain the retention data at any time after incorporation or to calculate the internal average organ dose induced by uranium provided that specific absorbed fractions are available. The dynamic relationship of the retention in plasma and blood after intravenously and orally administered uranium can easily be derived from the database for injection and ingestion. The calculated contents of uranium in organs or tissues (using the uranium concentration in foodstuffs published by UNSCEAR for Europeans) are compared with autopsy data available in the literature. According to this model, the whole body of a 75-year-old man contains 7 microg uranium, of which 76% is in the skeleton, 1% in the kidneys, and 2.1% in the liver.

Distribution of uranium in German bottled and tap water

“…For all three bodily fluids, the highest mean values were found in persons from the Halle region (Dobler et al, 2007a). For most of the world population the mean concentration in urine is about 10.0 ng U/L (Li et al, 2005). For Germany the mean uranium concentration in urine is 8.71 ng/L (Dobler et al, 2007a).…”

Estimating perchlorate exposure from food and tap water based on US biomonitoring and occurrence data

“…Studies done in vitro showed that dieldrin binds to estrogen receptors (Soto et al, 1995), but no estrogenic effect was noted in a study that used cultured cells (Tully et al, 2000). Epidemiologic and animal studies have not conclusively associated dieldrin exposure with risk for developing Parkinson's disease (Corrigan et al, 2000;Kanthasamy et al, 2005;Li et al, 2005).…”

“…In cases of retained DU shrapnel, the shrapnel acts as a source of chronic, low level exposure. After long term or repeated exposure, kidneys, liver, and bones can accumulate uranium with the largest amounts being stored in bones (Li et al, 2005). Uranium is eliminated in feces and urine; about 50% of the absorbed dose is eliminated in the urine within the first 24 hours.…”

Radiation dose assessment of exposure to depleted uranium

“…The ICRP has developed comprehensive biokinetic models for radionuclides for more than two decades (ICRP, 1979). The systemic biokinetic models of uranium (ICRP, 1995a), coupled with the GIT model of ICRP Publication 30 (ICRP, 1979), the new HATM (ICRP, 2006) and the human respiratory tract model (HRTM) of ICRP Publication 66 (ICRP, 1994a), were used to model the excretion and the retention of 234 U, 235 U, 236 U and 238 U in organs or tissues after incorporation (Li et al, 2005).…”