Whole body counters used in tracer studies cause a minimum of inconvenience for the patient. Their sensitivity permits use of smaller quantities of radioactive material than is required with small scanning instruments.
Those are unusual jobs for whole body counters, however. Scanners or other types of instruments are used more typically in following tracer isotopes.
Animal Research
Figure 20 Dogs about to be examined in a whole body counter.
How do dogs accumulate fallout isotopes in their bodies? This question was answered effectively by placing dogs in whole body counters and comparing the count from radioactive strontium-emitted gamma rays originating in their bodies with the count from a masonite phantom dog containing a known amount of radioactive strontium-85. It was found that female dogs increase their strontium retention while they are nursing newborn puppies. Strontium is much like calcium, which is a major component of milk. One dog measured had broken a leg in a fight. The counter showed above-average strontium accumulation for this dog, and it was conjectured that strontium, a “bone-seeking” element, had followed calcium to the point of bone repair and new bone growth.
Figure 21 A wild deer under a whole body counter.
Figure 22 Graph of whole body counter survey of four different animal species, showing differences in their retention of orally administered radioactive zinc-65.