ABSTRACT
This chapter describes results of an experiment to determine the gastrointestinal (GI) absorption of soluble uranium from drinking water by humans. In 1985, Wrenn et al. reviewed the published data on GI absorption and distribution of U in the body. In this review, estimates for the fraction of U absorbed by humans varied tenfold, from 0.8o/o to 8o/o, with a consensus "best estimate" of 1.4o/o. The International Commission on Radiological Protection (ICRP) has recommended the use of 5% for the GI absorption of soluble U by occupationally exposed workers.2 The GI absorption of U in humans may be affected by the concurrent consumption of food. Sullivan et al.3 and Willis 4 found that the absorption of U is three to seven times higher when given to rats on a fasting stomach than with food. Results obtained in four and eight subjects have already been reported.5•6
Consumption of Water Containing Uranium and Sample Collection
Twelve volunteers, normal in kidney function and free of any indication of complicating pathology, were selected after careful detailed medical, hermatological, biochemical, and urological examinations at the University of Utah Medical Center. Subjects collected 24-hour total output of both urine and feces each day for seven days so we could establish their normal background of intake and excretion of U. Then, during the next day (between 9:30 a.m. and 3:30p.m.), they drank, at their normal rate of drinking water intake, 900 mL of water containing approximately 90 pCP38U and 90 pCP34U. Urine and feces were collected for seven more days.
