Polonium was administered to humans for experimental purposes from 1943 to 1947; it was injected into four hospitalised patients, and orally given to a fifth. Studies such as this were funded by the Manhattan Project and the AEC and conducted at the University of Rochester. The objective was to obtain data on human excretion of polonium to correlate with more extensive data from rats. Patients selected as subjects were chosen because experimenters wanted persons who had not been exposed to polonium either through work or accident. All subjects had incurable diseases. Excretion of polonium was followed, and an autopsy was conducted at that time on the deceased patient to determine which organs absorbed the polonium. Patients' ages ranged from 'early thirties' to 'early forties'. The experiments were described in Chapter 3 of Biological Studies with Polonium, Radium, and Plutonium, National Nuclear Energy Series, Volume VI-3, McGraw-Hill, New York, 1950. Not specified is the isotope under study, but at the time polonium-210 was the most readily available polonium isotope. The DoE factsheet submitted for this experiment reported no follow up on these subjects.