Studies of the Biological Effects of Ra 226 , Pu 239 , Ra 228 (MsTh 1 ), Th 228 (RdTh), and Sr 90 in Adult Beagles

Abstract

The carcinogenic, hematological, pathological and biochemical effects of graded single doses of the titled radionuclides on a stock of beagle dogs were compared. Their influence on growth and metabolic changes were evaluated. Many toxi-city end points were used. Retention of radionuclides in beagles was measured from time of injection to time of death. Whole body retention and excreta were evaluated to double check retention values. Burden of injected radionuclides decreases with time due both to radioactive decay and biological elimination. Thus, comparison of radiotoxicity was made on total retained dose and dose rate bases. Details of measurement and methods for maintaining a colony of dogs and partial results on pathological effects are discussed.