Polonium 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
Polonium dichloride by dehalogenation of polonium tetrachloride, PoCl. Methods for dehalogenating PoCl include thermal decomposition at 300 °C, reduction of cold, slightly moist PoCl by sulfur dioxide; and heating PoCl in a stream of carbon monoxide or hydrogen sulfide at 150 °C. PoCl dissolves in dilute hydrochloric acid to give a pink solution, which autoxidises to Po(IV). PoCl is rapidly oxidised by hydrogen peroxide or chlorine water. Addition of potassium hydroxide to the pink solution results in a dark brown precipitate – possibly hydrated PoO or Po(OH) – which is rapidly oxidised to Po(IV). With dilute nitric acid, PoCl forms a dark