This is not usually a blog for science and/or politically related matters but this was too big for even me to pass by.
You may have heard of the russian defector, Alexander Litvinenko, who was recently poisoned and subsequently died. At first they thought it was thallium-poisoning, it now turns out he died from Polonium-210 introduced as a liquid into his digestive system. Polonium is a highly radioactive substance that emits alpha-particles.
Alpha-particles are nasty business. In school you learn that they almost don’t penetrate the skin and is therefore “harmless”. Noone actually learns that since they are easily stopped, they deposit all their energy in a small area and can therefore easily cause skin-cancer in large external doses and can destroy internal tissue if introduced into the body. Alpha-radiation is nasty stuff.