Cellular radiation doses of labeled neutrophils and platelets.

Radiation doses were calculated for human neutrophils and platelets labeled by phosphorus-32, chromium-51, gallium-67, technetium-99m, indium-111, and mercury-197. The cells were assumed to be spheres with radii of 4.87 microm and 1.07 microm, respectively, with all the radioactivity at either the center or uniformly distributed on the surface. Surprisingly high dose rates were found, due primarily to the small mass and therefore high radioactive concentration and to low-energy electrons, such as Auger electrons. Average total doses to these cells during their effective lifetime in the blood are presented.