Measurement of 210Po in Biopsied Human Red Bone Marrow

Natural levels of the radionuclides 210Po and 210Pb were determined in biopsied human red bone marrow. Aspirate biopsies taken from haematological diagnosis from 98 patients in eight UK hospitals were pooled into a single sample of marrow and measured by radiochemistry for 210Po. The calculated activity concentrations of 210Po and 210Pb in red marrow were both 24 mBq.kg-1, and the annual dose equivalent rate from both nuclides in red marrow is 13 μSv.y-1. 210Po and 210Pb in bone surrounding marrow cavities contribute a further 3 μSv annually assuming 1 Bq.kg-1 of 210Pb in (wet) bone. These values of activity and dose equivalent are several times lower than previously published measurements, which all measured autopsied marrow. A possible explanation for this low measured concentration is the absence in aspirate biopsied marrow of bone fragments which can contaminate autopsied marrow. (author)