Metabolism of Pu 239 in Adult Beagle Dogs

Abstract

The metabolism of plutonium in young adult beagle dogs was studied over a period of 4 years after a single intravenous injection of Pu(IV) in citrate buffer of pH 3.5. Three time periods were arbitrarily chosen to facilitate treatment of the plasma concentration and excretion rate data. For times greater than 3 weeks after injection, the per cent retention calculated from excretion measurement is R= 90.0--0.434t/sup 0.515/ when t is in days. The major part of the plutonium deposits in the skeleton and the liver, and the results of tissue measurements agree well with the retention calculated from excretion. No effect of dose level, age at injection, or sex could be demonstrated in the excretion studies. Comparison of the results with those of some early studies in which mongrel dogs were given much larger doses showed remarkable similarities. Plutonium metabolism in the dog is more like that in man than in rat. The liver deposition persists for long times in man and dog, but not in the rat. The retention in man is a little higher than in beagles, but the distributions are quite similar. The average dose rates and average cumulative doses to the skeleton and to the livermore » of the beagles are about equal (when calculated on the basis of uniform distribution). Skeletal damage greatly predominates, however. A limited preliminary comparison of skeletal effects of Pu/sup 239/ and Ra/sup 226/ on the basis of the amoumt of emergy dissipatod in bone shows that plutomium is more toxic. (auth)« less