# Ricin - How toxic is it? **URL:** \ **Category:** Factual Questions\ **Created:** [February 3, 2004, 8:14pm UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364 "2004-02-03T20:14:00Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Pepsi\_Classic](https://avatars.discourse-cdn.com/v4/letter/p/f19dbf/32.png) [@Pepsi\_Classic](https://boards.straightdope.com/u/Pepsi_Classic)\ **Post date:** [February 3, 2004, 8:14pm UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/1 "2004-02-03T20:14:00Z")
How toxic is ricin is comparison to other substances? It is really bad or just just a little toxic in comparison to the really bad stuff? ---
**Author:** ![jjimm](https://avatars.discourse-cdn.com/v4/letter/j/ba8739/32.png) [@jjimm](https://boards.straightdope.com/u/jjimm)\ **Post date:** [February 3, 2004, 8:19pm UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/2 "2004-02-03T20:19:23Z")
Very. The dose that killed Georgi Markov was [0.2 milligrams](http://www.cnn.com/2003/WORLD/europe/01/07/terror.poison.bulgarian/). The only good thing about it is that it isn’t tremendously effective if sprayed around. ---
**Author:** ![Moirai](https://avatars.discourse-cdn.com/v4/letter/m/96bed5/32.png) [@Moirai](https://boards.straightdope.com/u/Moirai)\ **Post date:** [February 3, 2004, 8:20pm UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/3 "2004-02-03T20:20:02Z")
How toxic? It’s deadly. Cheap and easy to make, a few grains can constitute a lethal dose. It must be inhaled or ingested, it does not easily cross the skin barrier. A few cites- [http://www.emedicine.com/emerg/topic889.htm](http://www.emedicine.com/emerg/topic889.htm) [http://www.bt.cdc.gov/agent/ricin/facts.asp](http://www.bt.cdc.gov/agent/ricin/facts.asp) ---
**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\ **Post date:** [February 3, 2004, 8:28pm UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/4 "2004-02-03T20:28:05Z")
Very toxic. From the overview: Ricin is a potent protein toxin derived from the beans of the castor plant (Ricinus communis). Castor beans are ubiquitous worldwide, and the toxin is fairly easily produced. Ricin is therefore a potentially widely available toxin. When inhaled as a small particle aerosol, this toxin may produce pathologic changes within 8 hours and severe respiratory symptoms followed by acute hypoxic respiratory failure in 36-72 hours. When ingested, ricin causes severe gastrointestinal symptoms followed by vascular collapse and death. This toxin may also cause disseminated intravascular coagulation, microcirculatory failure and multiple organ failure if given intravenously in laboratory animals. ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [February 3, 2004, 9:57pm UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/5 "2004-02-03T21:57:37Z")
> [@jjimm](#): > > The dose that killed Georgi Markov was [0.2 milligrams](http://www.cnn.com/2003/WORLD/europe/01/07/terror.poison.bulgarian/). > > The only good thing about it is that it isn’t tremendously effective if sprayed around. As you know, Markov was injected with Ricin via the tip of a trick umbrella. Apparently, the use and effects of aerosolized Ricin are entirely theoretical at this time: > [@](#): > > Accidental sublethal aerosol exposures which occurred in humans in the 1940’s were characterized by acute onset of the following symptoms in 4 to 8 hours: fever, chest tightness, cough, dyspnea, nausea, and arthralgias. The onset of profuse sweating some hours later was commonly the sign of termination of most of the symptoms. Although lethal human aerosol exposures have not been described, the severe pathophysiologic changes seen in the animal respiratory tract, including necrosis and severe alveolar flooding, are probably sufficient to cause death from ARDS and respiratory failure. [http://www.health.ri.gov/environment/biot/ricin\_chapter.htm](http://www.health.ri.gov/environment/biot/ricin_chapter.htm) ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [February 3, 2004, 11:07pm UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/6 "2004-02-03T23:07:29Z")
I remember reading that a single molecule of the poison is sufficient to kill a living cell by disturbing the metabolic pathways. ---
**Author:** ![Ravenman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ravenman/32/2929_2.png) [@Ravenman](https://boards.straightdope.com/u/Ravenman)\ **Post date:** [February 3, 2004, 11:18pm UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/7 "2004-02-03T23:18:16Z")
slight hijack - from the emedicine site above, I read this: “This basic structure of ricin is similar to those of the botulinum toxin, cholera toxin, diphtheria toxin, tetanus toxin, and insulin.” Ok, ricin, botulinum, cholera being similar, I can kind of get. But insulin? Is insulin considered a toxic substance? ---
**Author:** ![Moirai](https://avatars.discourse-cdn.com/v4/letter/m/96bed5/32.png) [@Moirai](https://boards.straightdope.com/u/Moirai)\ **Post date:** [February 4, 2004, 6:01am UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/8 "2004-02-04T06:01:23Z")
I don’t know abou tthat, but I do know what scares the hell out of me- ricin is considered a “kitchen” substance, which means that in my kitchen right now, I probably have the right chemicals to distill out the ricin protien from the rest of the castor bean. Holy cow. Apparently, the white supremacist movement in the US has had ricin for decades. One group (the “we hate everybody else psychos,” one would assume) was busted in the 1980’s with 200 lethal doses in their possession. But it doesn’t appear that they’ve been caught trying to kill anybody with it. ---
**Author:** ![antechinus](https://avatars.discourse-cdn.com/v4/letter/a/fbc32d/32.png) [@antechinus](https://boards.straightdope.com/u/antechinus)\ **Post date:** [February 4, 2004, 6:49am UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/9 "2004-02-04T06:49:12Z")
> [@Mangetout](#): > > I remember reading that a single molecule of the poison is sufficient to kill a living cell by disturbing the metabolic pathways. You may have read that in ‘Medical Toxicology - Diagnosis and Treatment of Human Poisoning’, 1988. - “It is believed that a single molecule of abrin or ricin is sufficient to kill a cell.” > [@](#): > > The latency period between ingestion and death is normally two-days. > The lectins consist of two protein chains (A and B) connected by a disulfide > bridge. The B chain binds covalently to the surface of the cell membrane, > whereas the A chain enters the cell and inhibits ribosomal protein synthesis by > splitting off adenine from rRNA. It is extremly simple to extract ricin from castor bean, but very dangerous. Ricin used to be used as a varmint poison in days of yore, but many of the peddlers of this stuff died whilst trying to make it. ---
**Author:** ![Brutus](https://avatars.discourse-cdn.com/v4/letter/b/91b2a8/32.png) [@Brutus](https://boards.straightdope.com/u/Brutus)\ **Post date:** [February 4, 2004, 9:19am UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/10 "2004-02-04T09:19:30Z")
> [@antechinus](#): > > You may have read that in ‘Medical Toxicology - Diagnosis and Treatment of Human Poisoning’, 1988. - “It is believed that a single molecule of abrin or ricin is sufficient to kill a cell.”. I read that as well, but in _Jurassic Park_. 😉 Is there any know ‘antidote’ for ricin poisioning? ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [February 4, 2004, 9:25am UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/11 "2004-02-04T09:25:53Z")
> [@EJsGirl](#): > > One group (the “we hate everybody else psychos,” one would assume) was busted in the 1980’s with 200 lethal doses in their possession. Well, a previous cite says that 0.2 milligrams has been a lethal dose, so this group must have had about 40 milligrams of ricin. Where did they have it hidden, under their thumbnail? This is an incredibly small amount – about the weight of a few sesame seeds. In fact, I wonder why they had _so few_ lethal doses around – seems like refining the beans from a single plant would likely give you several hundred lethal doses. ---
**Author:** ![Desmostylus](https://avatars.discourse-cdn.com/v4/letter/d/c57346/32.png) [@Desmostylus](https://boards.straightdope.com/u/Desmostylus)\ **Post date:** [February 4, 2004, 10:54am UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/12 "2004-02-04T10:54:36Z")
> [@jjimm](#): > > Very. > > The dose that killed Georgi Markov was [0.2 milligrams](http://www.cnn.com/2003/WORLD/europe/01/07/terror.poison.bulgarian/). I don’t believe that this is correct. > [@](#): > > [Deadly Toxin Ricin Found In London Apartment > January 13, 2003](http://pubs.acs.org/cen/topstory/8102/8102notw8.html) > > By injection, the fatal dose in an adult is **1 mg per kg of body weight** , but ricin is also lethal at slightly higher doses when inhaled or ingested. Initial symptoms are flulike, and death occurs within days from multiple organ failure. So you’d need something like 100 mg, not 0.2 mg. > [@Brutus](#): > > Is there any know ‘antidote’ for ricin poisioning? From the above: > [@](#): > > There is as yet **no antidote** , but Ellen S. Vitetta, a cancer researcher at the University of Texas Southwestern Medical Center, Dallas, and colleagues have developed a recombinant DNA vaccine that “works well in mice and is very safe.” She has applied for an NIH grant for eventual testing in humans and is working with a drug company to develop an oral formulation. The stuff in the envelopes was probably dried bean mash, which is about 5% ricin. You’d need about 100 mg / 5% = 2000 mg = 2 g of that stuff injected into you to kill you, or some larger amount swallowed or inhaled. ---
**Author:** ![Canadjun](https://avatars.discourse-cdn.com/v4/letter/c/76d3ee/32.png) [@Canadjun](https://boards.straightdope.com/u/Canadjun)\ **Post date:** [February 4, 2004, 2:19pm UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/13 "2004-02-04T14:19:34Z")
According to [http://www.emedicine.com/emerg/topic889.htm](http://www.emedicine.com/emerg/topic889.htm) the LD50 for aerosol or parenteral (i.e. by injection) exposure is 3 µg/kg. So, 0.2 mg in an adult is a reasonable lethal dose. ---
**Author:** ![Myron\_Van\_Horowitzski](https://avatars.discourse-cdn.com/v4/letter/m/9de053/32.png) [@Myron\_Van\_Horowitzski](https://boards.straightdope.com/u/Myron_Van_Horowitzski)\ **Post date:** [February 4, 2004, 3:16pm UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/14 "2004-02-04T15:16:42Z")
Sigh… I’ve grown castor bean in my garden; it’s a striking, interesting plant. Like angels trumpet, foxglove, monkshood, morning glories, poppies… Someday all of that stuff will be banned, probably. Always some psychopathic freak to mess things up for the rest of us. ---
**Author:** ![antechinus](https://avatars.discourse-cdn.com/v4/letter/a/fbc32d/32.png) [@antechinus](https://boards.straightdope.com/u/antechinus)\ **Post date:** [February 4, 2004, 11:31pm UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/15 "2004-02-04T23:31:35Z")
Hampsets ate my post last night - probably killed them. There is no known antidote once ricin has started having an effect. If swallowed, lastric lavage, induce vomiting followed by activated carbon would be a good idea. I didnt know about Vitettas work - thanks Desmo. The lowest \*\*subcutaneous \*\* lethal dose for man(LDLo) is 0.043 mg/kg. So maybe 3-4 mg for Markov. Oral LDLo in man is 0.3 mg/kg From RTECS - Register of Toxic Effects of Chemical Substances Ricin can be very easily extracted and purified to a powder, much more than 5% ricin, assuming the person doesnt kill them selves in the process. ---
**Author:** ![levdrakon](https://avatars.discourse-cdn.com/v4/letter/l/49beb7/32.png) [@levdrakon](https://boards.straightdope.com/u/levdrakon)\ **Post date:** [February 5, 2004, 2:50am UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/16 "2004-02-05T02:50:11Z")
How much ricin in a single castor bean? Would eating one kill you? How about animals? Does anything in nature eat castor beans? ---
**Author:** ![antechinus](https://avatars.discourse-cdn.com/v4/letter/a/fbc32d/32.png) [@antechinus](https://boards.straightdope.com/u/antechinus)\ **Post date:** [February 5, 2004, 6:13am UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/17 "2004-02-05T06:13:00Z")
> [@levdrakon](#): > > How much ricin in a single castor bean? Would eating one kill you? > > How about animals? Does anything in nature eat castor beans? If you ate a castor bean it would probably pass through without any damage. You would have to chew it up well for there to be a toxic and possibly fatal dose of ricin releasd. The beans contain 0.1-1% ricin - a fair bit - but it is well bound up. Leaves contain less ricin than beans. Ricin beans and leaves are extremely toxic to livestock. I am looking in Dangerous Properties of Industrial Materials and there are LDLo’s for a whole bunch of different critters - not hampters though. Another LDLo \*\*oral \*\* for humans published here is 2mg/kg. ---
**Author:** ![antechinus](https://avatars.discourse-cdn.com/v4/letter/a/fbc32d/32.png) [@antechinus](https://boards.straightdope.com/u/antechinus)\ **Post date:** [February 5, 2004, 6:15am UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/18 "2004-02-05T06:15:33Z")
Why is ‘hampsters’ so hard for me to spell. :wally ---
**Author:** ![antechinus](https://avatars.discourse-cdn.com/v4/letter/a/fbc32d/32.png) [@antechinus](https://boards.straightdope.com/u/antechinus)\ **Post date:** [February 5, 2004, 6:21am UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/19 "2004-02-05T06:21:28Z")
Here you go: > [@](#): > > The most common symptoms result from gastrointestinal irritation and > include burning of the alimentary tract, nausea, vomiting, diarrhoea, and > colicky abdominal pain. Severe poisoning produces haemorrhagic gastritis > and dehydration. A latent period of between 2 to 24 hours for non-allergic > symptoms to occur is common. Serious oral ingestions may produce symptoms > within 1-hour. The primary target organs are the kidney, liver and pancreas > although inhibition of protein synthesis by ricin A affects every organ. > The seeds of the Castor bean contain the highest concentration of ricin. > **Several well-masticated seeds are required to produce significant > toxicity. Four to five seeds may produce shock in juveniles whilst a > lesser number may produce nausea and vomiting and subclinical > bilirubinaemia. Eight to ten seeds may produce haemorrhagic gastritis or > dehydration. The lethal dose of ricin in man is estimated to be 1 mg/kg > body weight (approximately eight seeds). Because of the potential of > anaphylaxis one seed may be fatal.** ---
**Author:** ![Squink](https://avatars.discourse-cdn.com/v4/letter/s/b5e925/32.png) [@Squink](https://boards.straightdope.com/u/Squink)\ **Post date:** [February 5, 2004, 2:13pm UTC](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364/20 "2004-02-05T14:13:56Z")
> [@antechinus](#): > > Why is ‘hampsters’ so hard for me to spell. :wally Probably because everyone else spells it wrong too. A **[hamster](http://dictionary.reference.com/search?q=hamster)** is a fuzzy little rodent. A **[hampster](http://dictionary.reference.com/search?q=hampster)** is a [lidded basket](http://dictionary.reference.com/search?q=hamper) in which dirty fuzzy little rodents are placed prior to being taken to the cleaners, or maybe not. [Next page](https://boards.straightdope.com/t/ricin-how-toxic-is-it/227364.md?page=2)