THE POISON GARDEN website      Arum maculatum berries on a Cannabis leaf 


This free script provided by JavaScript Kit

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.


Full Entries


Tuesday 25th October 2016
Saturday 20th August 2016
Sunday 6th March 2016
Wednesday 3rd February 2016


Saturday 28th November 2015
Friday 27th November 2015
Monday 17th August 2015
Wednesday 15th July 2015
Friday 26th June 2015
Thursday 25th June 2015
Thursday 30th April 2015
Wednesday 29th April 2015
Wednesday 11th March 2015
Tuesday 3rd March 2015
Saturday 28th February 2015
Sunday 22nd February 2015

November 2014

Monday 24th November 2014
Saturday 8th November 2014

October 2014

September 2014

Wednesday 24th September 2014
Monday 1st September 2014

August 2014

Tuesday 26th August 2014
Saturday 16th August 2014
Tuesday 5th August 2014
Friday 1st August 2014

July 2014

Sunday 27th July 2014
Wednesday 23rd July 2014
Sunday 13th July 2014
Sunday 6th July 2014
Tuesday 1st July 2014

June 2014

Wednesday 25th June 2014
Tuesday 24th June 2014
Sunday 22nd June 2014
Monday 9th June 2014
Wednesday 4th June 2014

May 2014

Monday 26th May 2014
Sunday 18th May 2014
Wednesday 14th May 2014

April 2014

Sunday 13th April 2014
Saturday 5th April 2014
Thursday 3rd April 2014
Tuesday 1st April 2014

March 2014

Monday 31st March 2014
Tuesday 25th March 2014
Friday 21st March 2014
Monday 17th March 2014
Sunday 16th March 2014
Tuesday 11th March 2014
Tuesday 11th March 2014
Thursday 6th March 2014
Wednesday 5th March 2014
Saturday 1st March 2014

February 2014

Thursday 27th February 2014
Monday 24th February 2014
Wednesday 19th February 2014
Monday 17th February 2014
Thursday 13th February 2014
Monday 4th February 2014
Monday 3rd February 2014
Saturday 1st February 2014

January 2014

Thursday 28th January 2014
Thursday 23rd January 2014
Friday 17th January 2014
Wednesday 15th January 2014
Monday 13th January 2014
Thursday 9th January 2014
Tuesday 7th January 2014
Wednesday 1st January 2014

December 2013

Monday 23rd December 2013
Friday 20th December 2013
Tuesday 17th December 2013
Friday 14th December 2013
Thursday 12th December 2013
Sunday 8th December 2013
Wednesday 4th December 2013
Sunday 1st December 2013

November 2013

Friday 29th November 2013
Wednesday 27th November 2013
Tuesday 26th November 2013
Friday 22nd November 2013
Monday 18th November 2013
Friday 15th November 2013
Thursday 14th November 2013
Sunday 10th November 2013
Thursday 7th November 2013
Wednesday 6th November 2013
Friday 1st November 2013

October 2013

Thursday 31st October 2013
Sunday 27th October 2013
Wednesday 23rd October 2013
Monday 21st October 2013
Friday 18th October 2013
Friday 11th October 2013
Wednesday 9th October 2013
Tuesday 8th October 2013
Monday 7th October 2013
Tuesday 1st October 2013

September 2013

Monday 30th September 2013
Saturday 28th September 2013
Friday 27th September 2013
Monday 23rd September 2013
Sunday 15th September 2013
Monday 9th September 2013
Tuesday 3rd September 2013
Sunday 1st September 2013

August 2013

Sunday 8th September 2013
Tuesday 3rd September 2013
Sunday 1st September 2013

Tuesday 27th August 2013
Sunday 25th August 2013
Monday 19th August 2013
Friday 16th August 2013
Tuesday 13th August 2013
Friday 9th August 2013
Friday 2nd August 2013
Thursday 1st August 2013

July 2013

Saturday 27th July 2013
Sunday 21st July 2013
Wednesday 17th July 2013
Monday 15th July 2013
Saturday 13th July 2013
Friday 12th July 2013
Thursday 11th July 2013
Wednesday 10th July 2013
Tuesday 9th July 2013
Saturday 6th July 2013

June 2013

Friday 28th June 2013
Tuesday 25th June 2013
Friday 21st June 2013
Thursday 20th June 2013
Wednesday 19th June 2013
Saturday 15th June 2013
Sunday 9th June 2013
Saturday 8th June 2013
Saturday 1st June 2013

May 2013

April 2013

March 2013

February 2013

January 2013

December 2012

November 2012

October 2012

September 2012

August 2012

July 2012 blog

June 2012 blog

May 2012 blog

April 2012 blog

March 2012 blog

February 2012 blog

January 2012 blog

December 2011 blog

November 2011 blog

October 2011 blog

September 2011 blog

August 2011 blog

July 2011 blog

June 2011 blog


The POISON GARDEN website is not connected with Alnwick Garden Enterprises Ltd and/or The Alnwick Garden Trust.