The story so far: Nine years ago, on November 11, 2004, Yasser Arafat died. That he could have died from natural causes or some “lifestyle disease” was too unpalatable for his followers so they came up with a rather bizarre theory that he was poisoned with Polonium-210. After decomposing in Ramallah for eight years his wife and followers dug up his corpse to try to prove it.

As far as anyone knows there has been one detected and recorded deliberate case of Polonium-210 poisoning (from the rather authoritative Royal Society of Chemistry in the UK):

Polonium-210 is reported to have caused the fatal poisoning of former Russian spy, Alexander Litvinenko. Litvinenko died on the evening of Thursday 23 November [2006] at University College Hospital, London, UK. He fell ill on 1 November within hours of meetings in a central London hotel and, later, a sushi bar. Chemistry World asked John Emsley, author of Elements of murder: a history of poison, what is known about polonium-210 poisoning.

The poisoning and subsequent death of Litvinenko occurred in London not far from me. He actually died in a hospital across the street from the office I was then working in. I spent a few days walking past the massed ranks of the world’s media or eating lunch alongside them in Pret a Manger.

But that’s not my only experience with radiation. You see I have a Physics PhD (admittedly in another branch of physics) but I did study medical physics at university.

Low activity suite

So here’s how you measure infinitesimally low amounts of radiation: amounts so low that they are usually drowned out by what we call “background radiation”.

Background radiation is like the noise when you’re standing on a street. If someone is standing next to you, talking to you, you can probably hear them. Detecting low levels of radiation is like listening to a whisper on a busy street. Best if you listen to the whisper in a quiet room.

Detecting Polonium 210 after 8 years is like trying to hear someone whispering on a busy street in New York. While you’re standing in London.

So if you are serious about detecting very low levels of radiation you need something called a “low activity” room. This is not a place with comfortable chairs and soothing music.

We had such a room at the hospital in Sheffield where I studied this. It was a room in the basement and within that room was a smaller room. The small room was made entirely out of battle ship plate armour steel: the walls were up to 2ft thick. The door was massive and resembled that of a safe.

The steel came from a battleship that was forged before 1945. That is critically important. The steel had to have been made before July 16, 1945.

Just like the noise on a street, steel makes a radioactive noise. Steel made before the dawn of man’s explosive nuclear experimentation is measurably quieter than steel made since. So if you want to hear the whisper of a truly tiny sample of something radioactive, you need both a thick piece of steel to keep the background noise out and that steel to be very quiet too.

More here.