The Gastrointestinal Absorption of Organically Bound Forms of Plutonium in Fed and Fasted Hamsters

Summary

Values of about 0·005–0·01 per cent were obtained for the absorption in fed hamsters of plutonium ingested as Pu⁴⁺ citrate, isocitrate, phytate and malate complexes and Pu³⁺ ascorbate compared with about 0·003–0·004 per cent for Pu⁴⁺ nitrate. Replacing drinking water with tea did not affect the result for Pu⁴⁺ nitrate. Fasting hamsters for 8 h before the administration of plutonium citrate increased absorption to 0·1–0·2 per cent. An extra period of fasting for 4 h after administration did not lead to a further increase in absorption. Similar values were also obtained when plutonium citrate was administered after a 24 h fast, followed either by immediate access to food or a further 4 h fast. In hamsters fasted for 24 h before administration of either Pu³⁺ ascorbate or Pu⁴⁺ nitrate, about 6–7 per cent of the ingested plutonium was retained in the gastrointestinal tract after one week. At three weeks after ingestion of Pu³⁺ ascorbate, gastrointestinal retention had fallen 100-fold without an increase in absorption.

• plutonium
• gastrointestinal absorption