Ingestion, uranium

Uranium ingested from food and water ingestion ranges from 1-5 pg uranium in uncontaminated regions to 13-18 pg uranium in uranium mining areas (ATSDR, 1999). The absorption of uranium across the gastrointestinal tract is related to the solubility of the compound and generally increases with increased solubility. Only a small fraction is... 

About 99 percent of the uranium ingested in food or water will leave a person s body in the feces, and the remainder will enter the blood. Most of this absorbed uranium will be removed by the kidneys and excreted in the urine within a few days. A small amount of the uranium in the bloodstream will deposit in a person s bones, where it will remain for years. 

Working with uranium requires the knowledge of the maximum allowable concentrations that may be inhaled or ingested. 

Small amounts of uranium are found in rock, sod, air, water, and food, and it is estimated that total annual intake of uranium by human adults approximates 460 pg by ingestion of food and water, and 0.6 pg by inhalation (Fisenne et al., 1987 Pietrzak-Flis et al., 2001 UNSCEAR, 2000a, b). Natural uranium is composed of three isotopes, U, and U, in the proportions shown in Table 29.1. 

Leggett, R.W., Harrison, J.D. (1995). Fractional absorption of ingested uranium in humans. Health Phys. 68 484-98. 

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