Measurement of Polonium-210 in Human Blood

Abstract

POLONIUM-210 is a naturally occurring alpha-emitting isotope of the uranium series derived from decay of its long-lived parent, lead-210. Polonium-210 is present in most plants and foodstuffs, as well as in human tissues^1–3. Body burdens of this isotope are usually determined by measuring its activity in tissue samples or urine^2,4,5. Tissue samples other than teeth are not readily available during life, however, and 24 h urine collections may be difficult to obtain and process, yet are often necessary to quantify urinary excretion. We have found that polonium-210 can be easily detected in 10 ml. human blood samples by a simple radiochemical and counting technique. The measurement of polonium-210 concentration in blood may thus be a practical method of estimating body burdens of this isotope, as well as of its parent lead-210². As tobacco smoke has been shown to contain trace amounts of polonium-210⁶, we have related blood concentrations to smoking habits in a group of middle-aged men.