Polonium 210 November 28, 2006Posted by dorigo in food, news, physics, science.
Polonium 210 is one of the most poisonous substances on earth. A powerful alpha emitter, with a half-life of 138 days and an emission energy of 5 MeV, Polonium is not a substance anyone should mess with.
As with all alpha emitters, this substance is not dangerous by itself if kept outside of one’s body: alpha projectiles only travel few millimeters in air, and fail to create a danger. It is only through inhalation or ingestion that the horrible effects of this substance become evident. The energy released by this fast-decaying isotope is quite high (a unbelievable 140 watts per gram according to wikipedia), and the amount of damage manifests very quickly in the hosting body, as was demonstrated a few days ago with the death of the russian spy Alexsandr Livitnenko in London.
Livitnenko was allegedly poisoned while eating at a sushi bar near Piccadilly Circus, in the center of the city: most probably his killer sprayed a small amount of the substance over his meal. In any case, the substance is volatile -probably the radioactive decay spontaneously sublimates atoms of the material by spallation- and its nasty effects are so powerful that even less than a nanogram can be deadly. Quoting wikipedia again, the maximum allowable amount of ingested substance is 7 picograms – a sphere 1 micron in diameter is already harmful!
I think it is wise to wait for at least 10 half-lives to visit that sushi bar now. That’s 7 years!