Polonium smokers

Polonium was discovered in 1898 by Marie and Pierre Curie in their search for the sources of radioactivity in pitchblende. Polonium has 27 isotopes and is highly toxic and very radioactive. It has been suggested that the isotope 210Po, a natural contaminant of tobacco and an a-particle producer (see Section 21.1), might be at least partly responsible for the incidence of cancer in smokers. 

Polonium has been found in the tobacco used in cigarettes and other products. The amount of polonium taken in by a smoker is approximately equal to that taken in from all other sources. Polonium must be added, therefore, to the list of harmful chemicals inhaled during smoking. 

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