The toxicology tests from the Litvinenkos autopsy reportedly show two separate spikes in his radiation poisoning, indicating that he swallowed Polonium 210 on two different occasions about two weeks apart. Is Polonium 210 a sure-fire poison?
Yes and No. Yes if a microgram of Polonium 210 is injected intravenously into the blood stream. But not necessarily, if it is ingested in food or a beverage. Unlike the gamma particles from most other radioactive isotopes, the alpha particles from Polonium 210 are too large to go through the skin. The intestine wall also blocks about 95 percent of these particles from getting into the blood stream before they are expelled from the body. So it is possible to ingest a microgram of Polonium 210 and not die. In any case it is slow-acting– Litvinenko lived for at least 3 weeks– and it can be successfully treated with available antidotes.
