Summary
Using the techniques of 241plutonium autoradiography and plutonium α-autoradiography the distribution of intravenously injected plutonium in the rat rib has been investigated, at times up to 4 months after injection. The results showed that at some time plutonium either became buried in the bone cortex or was resorbed. Plutonium which was resorbed was found in osteoclasts and macrophages. Subsequently, much of the resorbed plutonium was redeposited. The dosimetric implications of the results are discussed.