Confusing Chemistry

The threat of a chemical attack in the UK is back in the news. This time it's osmium tetroxide that's suspected to be the dirty bomb builders agent of choice.

So, being a Brit living with the constant 'It's not if, it's when' cloud hanging overhead, I ventured forth to establish the likelihood of such an attack, and the ramifications should we ever have to endure one. Here's a few of the facts I found :

Would it be a viable chemical for terrorists to use?

Financial Times

"Scientists say that the material would be an almost ideal chemical agent for terrorists wanting to cause casualties and mass panic in a confined space"

BBC

"Scientists believe it is an "extremely unlikely" candidate for use in a dirty bomb... handling the chemical would be difficult for any terrorist".

Hmm... there appears to be a slight difference of opinion.

OK, let's assume that the terrorists decide to give it a whirl...

Would it be cost effective and easily available?

Financial Times

"Terrorism experts and security officials say ... osmium tetroxide can be bought over the internet for £17 per gram.

BBC

"One gram costs about £96-£130... You wouldn't get a lot of osmium for more than £30,000"

Have the BBC not cottoned on to Ebay yet?

Anyhow, using their figures, £30k...Incidentally, I wonder where they plucked that from?... Is it the standard bomb makers budget? And, what a peculiar turn of phrase: "You wouldn't get a lot of osmium for more than £30,000" - I would say that you could get as much as you like, governed only by how much more than £30k you're prepared to pay. Anyway, back to the calculator... using their figures, £30k would buy you somewhere between 230g and 312g of osmium. If, however, the terrorists have a webwise buyer that sniffs out the FT's source, they could procure 1,764g or 1.76Kg. Let's hope they are all supporters of High Street shopping, eh?

Right then, now we know how much can be bought with the assumed budget, give or take the odd one and a half kilos ...

How much would be required to pose a serious health risk?

Financial Times

"Just a few millionths of a gram in a cubic metre of air would have corrosive effects on the eyes, skin and lungs."

BBC

"Given its reactive nature, it is likely to be destroyed in any actual explosion... If you had 10g and you opened it up in a normal-sized room, within a couple of minutes it would cause people's eyes to stream... Some people might feel a bit tight in the chest.... Osmium tetroxide is not a fatal substance"

Hold on a mo; I need to get my head around this.

Right, I think I've got it. The true effects lie somewhere between a few millionths of a gram causing eye, skin and lung corrosion and 10 grams, some several million times greater, generating watery eyes and, if you're unlucky, a bit of a wheezy chest. Fine!

Perhaps the guys who ran the original exclusive can better inform me:

ABC News

"It's a nasty piece of work.... It irritates the eyes, lungs, nose and throat. It leads to an asthma-like death, what we call a 'dry-land drowning... for example, if the bomb used in the 1993 World Trade Center attack had produced such fumes, they would have wiped out the first police and rescue workers on the scene."

I'm seriously confused now, so I'm off to bed to dream about tangerine trees and marshmallow pies; I need to get closer to reality.