Building bombs in the name of science

Travel by air has increased by over 60% in the last decade and The International Air Transport Association - IATA - expect global air traffic to reach 3.6 billion passenger journeys by 2016. Currently estimates suggest that, at any moment in time, there are at least 1 million people airborne aboard planes all around the world. But as air traffic grows, so do concerns about smuggling and security, particularly at the moment, with governments in many countries describing the threat from terrorism as severe. So keeping people safe is a major priority; but the processes can be intrusive and can also cause unpleasant delays at airports. Jackie Akhavan is a Professor of Explosive Chemistry at Cranfield University and works on how to best detect concealed explosives, as she explained to Ginny Smith...

Jackie -  At the moment, the new systems is the SORS which is the Spatially Offset Raman Spectroscopy,  where you can shine light and it'll actually go through a bottle into your liquid explosive.  It's very, very new technology and it's been actually brought into airports at the moment.  So hopefully in the future, we should be able to go through airports a little bit quicker than we are now.

Ginny -  And would that mean that I'd be able to take my bottle of water onto the plane with me, rather than having to empty it out and then refill it?

Jackie -  Realistically, yes. 

Ginny -  Brilliant news.  Are there any other kind of systems that are in place at the moment?

Jackie -  There is another one that's been looked at, which is a PVS system which is Permittivity Voltage Sensing and this is a new way of looking at their electrical properties which is rather different than the SORS which is the spectroscopic properties.

Ginny -  Interesting!  I think I've heard that you've also been using bees to detect bombs.  Is that true?

Jackie -  Yes.  We have had look at the bees.  Recently, I was at a presentation at New Scotland Yard and they've been able to train bees within 10 minutes using the Pavlov Dogs type of training to detect people who have diabetes, the smell in their breath.  They also claim that they also be able to detect some forms of cancer.  So, with these all for hindsight, they thought that bees might be able to detect explosives.  We've actually manufactured pure explosives to the bees and we found that the bees couldn't actually detect the pure explosive.  What it could detect was the additives in the manufactured explosives.  So, these are the volatile additives.  So, in one way, it might work but unfortunately, it's not the pure explosive that bees can detect.

Ginny -  So, we're not going to be seeing swarms of bees at customs anytime soon then.

Jackie -  No.  I must admit, I felt really sorry for the bees.  Another thing I thought to myself was, could the public actually trust their selves to bees.  That's the other thing, so I don't think you'll see them pretty soon, no.

Ginny -  So, you spent your time trying to develop new types of explosives that can evade detection methods so that you can improve these detection methods.  Is that right?

Jackie -  We're not actually developing explosives to evade it.  What we have the capability to do is to manufacture improvised explosives and these are the ones that are very similar to the terrorist type of explosives which of course, that's what you want your detectors to detect.  And I must admit most detectors will detect the explosives.  The hardest thing is they go off with everything else as well.  So, like the perfume, so it's thought non-goers which is the most difficult things.

Ginny -  Okay, so what you might have in the bottle might not be an explosive.  It might be shampoo and it can still flag it up.

Jackie -  I don't know what shampoo does but Chanel #5 certainly will do.  It's something that's quite volatile.

Ginny -  How many different types of explosives are there and how can you make one thing that can detect all of them?

Jackie -  There's numerous explosives out there and the hardest thing is, it's very difficult to make one thing that will detect an explosive.  So, you will probably have an array of detectors.  So, maybe using the SORS, the Raman spectroscopy, linked to maybe this one that does the electrical properties.  and we also do another one for European Union contract on colour metrics which is another technique where polymers will change colour when they come into contact with explosive vapour.  So, I don't think we will rely on one technique.  There'd be an array of techniques.

Ginny -  I imagine, it must be quite tricky as well to keep of sort of one step ahead as people keep developing these new homemade explosives.  Very quickly, can you tell me how you go about trying to do that?

Jackie -  In respect, you read the literature, you keep in contact with what's going on out there.  You also relies with obviously the home office and the other areas which also keep an eye on what's out there.  We try as chemist to predict what might be the next type of homemade explosives.  The people making them are chemists.  We're chemists, so hopefully, we'll be on the same wavelength.