Effect of external irradiation on the gastrointestinal absorption of uranium and neptunium in rats

Abstract

Purpose : The gastrointestinal absorption and systemic distribution of uranium and neptunium were determined after external gamma irradiation. Materials and methods : Rats were exposed to a single whole-body dose of gamma radiation (6 Gy; 0.75 Gy.min -1) . Three days after irradiation they were orally and/or intravenously contaminated with 100 μ g.kg -1 uranium or 3 kBq.kg -1 neptunium. The gastrointestinal absorption and organ distribution of both radionuclides were measured 6 days after irradiation. Results : External irradiation increased the intestinal transit time of uranium and neptunium but had no effect on their gastrointestinal absorption. The average fractional absorption was determined to be 0.93 and 0.98% (uranium) and 4.7 and 4.8% (neptunium) for the irradiated and non-irradiated rats respectively. The excretion of uranium and neptunium was not affected by the irradiation. Conclusion : A 6 Gy whole-body irradiation (gamma; 0.75 Gy.min -1) did not affect the absorption of uranium and neptunium after oral intake.