A biokinetic study of 209Po in man

Five adult volunteers participated in a biokinetic study of radioactive polonium. Portions of about 10 Bq of 209Po were orally administrated to four of the volunteers in a single ingestion. The fifth volunteer ingested a daily amount of 53 mBq of 209Po for 243 d to study the time to achieve equilibrium between intake and excretion for protracted intakes. For the subjects ingesting single intakes of 209Po complete sampling of urine and feces was subsequently collected the first few days upon the ingestion. The samples were processed with radiochemical extraction and analyzed with alpha spectrometry. In the study, the maximum daily excretion rates in feces were 18-50% of the ingested activity, observed within 3 d after intake. Regarding the urine excretion, the daily excretion peaked, on average, at 0.15-1% of the ingested activity within two days upon intake. These results indicate an average gastro-intestinal uptake fraction of 0.46 ± 0.08, which agrees well with earlier biokinetic studies of polonium in man.

► Human metabolism of an oral intake of polonium. ► 4 individuals were administrated about 10 Bq polonium-209. ► Gastro-intestinal uptake fraction, if orally administrated polonium-209 was investigated. ► The biological half-time of polonium in human body was studied.