Chemist and popular science writer John Emsley’s latest work is The Elements of Murder: A History of Poison. In 1995, he won Britain's Science Book Prize for his Consumer's Good Chemical Guide. Formerly, he conducted research and lectured at London University for 20 years.

Washington Profile: Poison has been used widely throughout history as a weapon of murder.  How would you say the culture of poison has changed in recent times?

John Emsley: I don’t think the culture of poison has changed.  I think it is still used today.  Saddam Hussein particularly, and his secret police, were fond of using poison to dispose of their enemies.  They used thallium….  They poisoned quite a few people in London in the 1980s with it, and he even poisoned some of his senior military men.   As you said, it’s been used throughout history.

WP: Why would one use poison as opposed to another weapon?

Emsley: I think in order to do it surreptitiously and perhaps even hope to get away with it without the person suspecting that they have been poisoned, until it’s too late.  For example, if you do use thallium, which is a slow poison to take effect, the symptoms only begin to appear after about three days.  Of course the person who’s delivered the poison can be out of the country before anyone suspects anything has happened.  It does offer advantages, as opposed to an assassination with a bullet or something like that. 

WP: What can you say about Litvinenko’s case, who appears to have been poisoned with polonium 210, which was quite quick to take effect?

Emsley: I’ve never heard of a case of that being used before.  It does offer advantages in that the dose can be exceedingly small.  We are talking now less than perhaps a millionth of a gram.  It has been suspected in Litvinenko’s case that it was about a milligram.  Now that’s far smaller than any conventional poison.  And of course in a curious sort of way, I suspect they may have given him too much because they wanted the poison to take effect more slowly.  If you get polonium inside your body, it’s what’s called an alpha emitter, and alpha particles are released as each atom disintegrates.  Alpha particles are particularly dangerous at destroying whatever is around them.  Whatever organ of his body this polonium ended up on was going to be trashed by the radioactivity.  Of course if they’d given him less, perhaps it might have taken him longer to become ill and then admitted to a hospital and then die.  It might have gone unnoticed, because, obviously, a diagnosis or autopsy doesn’t generally include a measure of radioactivity.  To begin with, his hair fell out, and they thought he was a victim of thallium poisoning.  When they tested his blood they couldn’t find very much thallium, not more than, say, background levels. And then they suspected it was radioactive thallium.  There is an isotope of thallium which would have disappeared by the time they were testing.  But then the tests for radioactivity showed that he was radioactive, and of course eventually you can tell from the rays given off… what the element is that you are dealing with; then they realized it was polonium.  It’s all very sinister…

WP: Yes, it sounds like a murder mystery.

Emsley: The thing about polonium is that in order to make it, you’ve got to have access to a nuclear reactor.  And it’s made from bismuth -- if you put bismuth in a nuclear reactor, it is bombarded with neutrons and transformed into polonium 210.  Now about a 100 grams is made of this every year because it does have some uses; a piece of polonium all by itself, because of its radioactivity, gets incredibly hot, up to something like 500 Celsius, and you can use that heat to generate electricity, and some of the things sent into space have had polonium thermoelectric cells.  So there was a reason to make it for some people, but you do need access to a nuclear plant in order to do it…. I can’t for a minute believe that [this kind of poisoning] has anything to do with Chechnya or any of the instable states in the Middle East – it’s got to have been some kind of quite sophisticated secret agency that was doing this.  I can’t really say, but there has been so much speculation, because [Litvinenko] was blaming the Russian secret police of which he was once a member. He should know if anyone knows what they are capable of. 

WP: This is not the first case of poisoning of a prominent public figure in the former Soviet Union.  I’m sure you remember Viktor Yushchenko.  What are your thoughts on what happened there?

Emsley: The only thing that came to light there was that he was poisoned with dioxin.  It’s been known for a 100 years that dioxin will produce a terrible form of acne.  It’s actually got the name chloracne.  It’s something that engineers used to suffer from a 100 years ago, because engineering oils were very often contaminated with it, and then it used to come out on their face and on other parts of their bodies, these terrible pustules and suppuration; it’s a body reaction to a certain chemical.  Nowadays, all those sorts of chemicals are no longer used, anything with traces of dioxin is very carefully monitored.  But the people getting at Yushchenko knew this, and -- I am purely speculating -- but obviously he has a very nice personality and he was coming over very well on television.   You give him a dose of that, and very quickly his face became a mass of scares, and [it] scarred his image, literally.  And … that’s a toxin that can be made in the laboratory relatively easily.

WP: To your knowledge, is there a perfect poison, one that leaves no trace?

Emsley: I wrote this book, The Elements of Murder, and it’s a popular chemistry book.  I’m interested in these elements that there are in history and in medicine and in the environment, and their possible effects today on everyone.  But I also included chapters on actual murders where they have been deliberately used, but I reassure in the beginning of the book…that it is very difficult nowadays for the ordinary person to get hold of toxic materials.  But most certainly if you die under any suspicious circumstances, then an autopsy and an analysis will reveal what it is that you’ve been poisoned with.  There is no undetectable poison.  In America, you had a serial killer nurse who used adrenalin as the toxin, about ten years ago.  That’s a perfectly natural chemical that our own bodies produce.  And all she was doing was just injecting people with it.  If you have a heart failure, you give injections of adrenaline in order to start it again.  She was just pumping people with this not to kill them, but to excite the heart so that it just broke down, so now that’s almost undetectable because it’s a naturally occurring chemical.  If a death is suspected of being due to poison, there is always a way in which it would be possible to detect what it was simply because forensic analysis and chemical analysis is now so good, even when it’s a natural chemical that’s been used like adrenalin.