Strontium Studies in Beagles

Abstract

Continuous skeletal irradiation of adult beagle dogs from Sr90, Ra226, Ra228, Th228 and Pu239 at dose rates up to 10 rads per day for times between 1 and 4 years had no demonstrable effect on the metabolism of an I.V. injected Sr85 tracer. Confinement in metabolism cages 3 hours prior and 4 days after Sr85 injection reduced Sr85 retention to about 70% of that in dogs kept in their kennel runs. Retention of Sr85 decreased as both the age at injection and the time after injection increased. In 6 month old puppies, the biological retention of injected Sr decreased from 81% at 4 days after injection to 46%, at 200 days, whereas in 9 year old adults, retention decreased from 32% at 4 days to 10%) at 200 days. The fact that Sr retention was less than Ra retention was verified in a Sr85-Ra226 double tracer experiment.