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Pontifications on Poison

Being some ramblings on events associated with poisonous plants.

Tuesday 25th March 2014

It seems that every new story about ricin made from Ricinus communis, the castor oil plant, is obliged to include some new level of fantasy though, to be fair, the latest does, so far, seem to be avoiding some of the usual clichés associated with previous events.

For reasons unknown a student at Georgetown University in Washington D.C. decided to try one of the many ‘ricin recipes’ that, as I’ve said ad nauseum, aren’t. And then, in what looks like an act of such stupidity that one fears for the admission standards in US universities, he decided to show it to ‘a resident assistant’ who, unsurprisingly brought the matter to the attention of the authorities.

Ricinus communis, the castor oil plant

The good news is that reports of the case have made it clear there is no indication of a terrorist motive. I don’t mean it is good news that there is no terrorism motive, though that is true. I mean it is good news that the press hasn’t tried to hang the terrorism label on this story. For once, even the headlines, mostly, stay away from sensationalism.

USA Today has ‘Georgetown student arrested after making ricin in dorm’.

CNN keeps it very simple with ‘Georgetown University student accused of ricin possession’.

The Daily News goes for ‘Georgetown student made ricin in his dorm room: court documents’.

The Voice of Russia looks beyond the discovery to ask ‘How Deep in Legal Trouble is Ricin Georgetown Student?’

Only the Huffington Post tries to up the drama with ‘Georgetown Student Arrested For Making Deadly Chemical Ricin In His Dorm’. That’s rather like saying ‘Huffington Post Editor Drives Car With Deadly Petrol In Tank’.

Unsurprisingly, the publication taking the most interest and, therefore, providing the most detail is The Hoya, ‘Georgetown University’s newspaper of record since 1920’.

Ricinus communis, the castor oil plant

It is from here that we learn more about the ‘bag of homemade ricin’ referred to in other reports (though Huff Post ups the ante to ‘bags’ something that we’ll see is simply laughable).

According to The Hoya, the bag contained 123 milligrams of ‘the substance in his possession’. I have a lot of difficulty visualising small numbers. A level teaspoon is said to hold 5 grams of something like salt so 123 milligrams is about one fortieth of a teaspoon. I’m still not sure I can visualise that but I can see that you wouldn’t need bags (in the plural) to hold it.

But then The Hoya gives the key piece of information, ‘within that, the concentration of toxin was 7.7 micrograms per milligram’. So, as usual with these stories, we’re not talking about ricin at all. We’re talking about processed castor beans containing ricin in the same way that the castor beans legally available to anyone who wishes to grow the plant contain ricin.

The trouble I had trying to visualise 123 milligrams is nothing to the difficulty of trying to get to grips with the 947 micrograms of ricin contained in it. It is impossible to be completely accurate about what is a lethal dose of ricin because there is so little evidence. Best guess is that a normal adult would need to be injected with around 1800 micrograms of ricin. Inhalation would be about the same depending on the particle size and assuming all of the ricin was fully inhaled and ingestion would be considerably higher. So, the total found in this student’s possession is about half a lethal dose in the best of circumstances.

Ricinus communis, the castor oil plant

The new level of fantasy I referred to comes in comments attributed by The Hoya to Dr. William Daddio, Adjunct Professor of Microbiology and Immunology, Georgetown Medical School and Professor of Sociology and Anthropology at Georgetown University where he teaches courses in bio-terrorism and terrorism.

It is this paragraph that worries me;

‘“With the amount he had under the potency according to the lab tests, in order to potentially kill somebody, they would need to inhale it, which wouldn’t be hard to do, or be injected with it, which, as you would suspect, would be fairly simple,” Daddio said.’

I have three issues with that. First, as above, the student didn’t have enough ricin to kill anybody. I contacted Dr. Daddio to see if he had been correctly reported. From his reply, it would seem that his comment on the amount available was based on the first lab report that spoke about 123 milligrams of ricin rather than 123 milligrams in total with a much lower ricin content. The Hoya story does have a correction saying that it originally said that 123 milligrams of ricin had been found.

Ricinus communis, the castor oil plant

Second, the idea that getting someone to inhale ricin ‘wouldn’t be hard to do’ is not one I recognise. The notion that ricin can be lethal when inhaled comes from a 1996 study where monkeys were fitted with face masks and forced to inhale very finely ground ricin. Unless you can persuade your victim to wear such a mask, and are able to produce pure ricin in the finely ground form necessary for it to reach deep enough into the lungs to be absorbed, you would need much more than a single lethal dose to allow for poor inhalation and poor absorption. Dr. Daddio did confirm that he had said that getting someone to inhale ricin would be quite simple. I’ll have to disagree on that point.

And my third concern is with the idea that injecting ‘would be fairly simple’. On this point, it seems The Hoya either misheard or misreported Dr. Daddio because, in his email to me, he agreed that injecting someone with ricin would be complicated. When talking about the claims that ricin could be used as a mass murder weapon I always ask my audience how easy they think it would be to get potential victims to form an orderly line so as to receive an injection into the bloodstream. (Remember, the method used to kill Georgi Markov failed on his colleague, Vladimir Kostov, and hasn’t been used since 1978.)

While waiting to finish this off I was advised of a piece on the subject on the Nature’s Poisons blog. I won’t go through that in detail though I’ve expressed some of my concerns in the comments. I do, though, want to consider one point.

Justin says that castor beans contain 1-5% ricin. The higher figure is the one I’ve always referred to but there is bound to be a range. But, take the lowest figure, 1%. This is for the castor bean before the oil is removed. The general estimate seems to be that beans are 50% castor oil so the mash remaining after simply crushing castor beans should be a minimum of 2% ricin. But 7.7 micrograms per milligram is 0.77%. In other words, whatever the Georgetown student did had the effect of destroying some of the ricin present.

I always criticise those who take one piece of evidence and argue that it offers absolute proof of something so I’ll hold back from that and say that this case, at least, supports my belief that the available ricin recipes are not useful to anyone seeking to produce ricin of a high enough purity to have the potential to cause death.

And I’m also going to hold back from trying to ascribe motive to this young man. But, if I were writing fiction based on such a storyline, I’d certainly make the protagonist a pitiful individual suffering great unhappiness in a strange environment and wanting to show that he was someone to be reckoned with. But I wouldn’t destroy his life chances completely by giving him a long sentence in a US federal prison, an outcome I fear will occur in the real world.

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