# Toxin
**URL:** https://boards.straightdope.com/t/toxin/50622
**Category:** Factual Questions
**Created:** [January 18, 2001, 2:53am UTC](https://boards.straightdope.com/t/toxin/50622 "2001-01-18T02:53:34Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@insider](https://boards.straightdope.com/u/insider)
#### Post date: [January 18, 2001, 2:53am UTC](https://boards.straightdope.com/t/toxin/50622/1 "2001-01-18T02:53:34Z")
What is the most deadly toxin known to science? Both natural and synthetic?
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### Author:  [@KarlGauss](https://boards.straightdope.com/u/KarlGauss)
#### Post date: [January 18, 2001, 3:00am UTC](https://boards.straightdope.com/t/toxin/50622/2 "2001-01-18T03:00:55Z")
**Ricin** , from castor beans may qualify as the most potent toxin. Use “ricin” in any search engine for more info.
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### Author:  [@evilhanz](https://boards.straightdope.com/u/evilhanz)
#### Post date: [January 18, 2001, 3:50am UTC](https://boards.straightdope.com/t/toxin/50622/3 "2001-01-18T03:50:00Z")
A toxin is a poisonous substance produced by an organism. By definiton, it’s natural. If you’re referring to any substance man-made or otherwise, I think it breaks down into the following categories. (Bear in mind, that the relative lethality of various substances is subjective.)
Toxin (including venoms): Ricin
Chemical Agent: VX, a nerve agent (.01 gm)
Biological Agent: Anthrax
Element: Plutonium (micrograms)
Immunization against Ricin and Anthrax is possible. Wear a gas mask and VX will dissipate. Plutonium, however, has a half-life of about 24k years. You can make a case for any of these, and others.
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### Author:  [@Patty\_O\_Furniture](https://boards.straightdope.com/u/Patty_O_Furniture)
#### Post date: [January 18, 2001, 4:01am UTC](https://boards.straightdope.com/t/toxin/50622/4 "2001-01-18T04:01:50Z")
Okay where does botulin fit in here? I know I’ve heard it touted as the most lethal neurotoxin many times.
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### Author:  [@Squink](https://boards.straightdope.com/u/Squink)
#### Post date: [January 18, 2001, 5:17am UTC](https://boards.straightdope.com/t/toxin/50622/5 "2001-01-18T05:17:02Z")
I think that saxitoxin as purified from the dinoflagellates which cause red tides holds the record for lowest LD50. It’s a very potent sodium channel blocker. Cholera toxin is also pretty good, with a few molecules serving to kill the average cell.
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### Author:  [@evilhanz](https://boards.straightdope.com/u/evilhanz)
#### Post date: [January 18, 2001, 5:57am UTC](https://boards.straightdope.com/t/toxin/50622/6 "2001-01-18T05:57:51Z")
If you want to talk strictly in terms of LD50 - the quantity of toxin necessary to cause death in 50% of infected subjects, it’s Botulism, no question. Here’s a list from “Medical Management of Biological Casualties Handbook” from USAMRIID. [Accueil - L'univers du chien](http://www.vnh.org/BIOCASU/Appxc.html) However, this list ignores such improtant details as the resilience of the microbe, manner of delivery, and likelihood of secondary infection. Accounting for all variables, Anthrax tops THAT list, at least according to the OSD. [http://www.anthrax.osd.mil](http://www.anthrax.osd.mil) (I said this was subjective) 🙂
List below shows agent, LD50, # of microbes, source.
> [@](#):
>
> Appendix C: Comparative Lethality of Selected Toxins And Chemical Agents in Laboratory Mice
>
> AGENT LD50 MOLECULAR SOURCE
>
> (m g/kg) WEIGHT
>
> Botulinum toxin 0.001 150,000 Bacterium
> Shiga toxin 0.002 55,000 Bacterium
> Tetanus toxin 0.002 150,000 Bacterium
> Abrin 0.04 65,000 Plant (Rosary Pea)
> Diphtheria toxin 0.10 62,000 Bacterium
> Maitotoxin 0.10 3,400 Marine Dinoflagellate
> Palytoxin 0.15 2,700 Marine Soft Coral
> Ciguatoxin 0.40 1,000 Marine Dinoflagellate
> Textilotoxin 0.60 80,000 Elapid Snake
> C. perfringens toxins 0.1 - 5.0 35-40,000 Bacterium
> Batrachotoxin 2.0 539 Arrow-Poison Frog
> Ricin 3.0 64,000 Plant (Castor Bean)
> alpha-Conotoxin 5.0 1,500 Cone Snail
> Taipoxin 5.0 46,000 Elapid Snake
> Tetrodotoxin 8.0 319 Puffer Fish
> alpha-Tityustoxin 9.0 8,000 Scorpion
> Saxitoxin 10.0 (Inhal 2.0) 299 Marine Dinoflagellate
> VX 15.0 267 Chemical Agent
> SEB (Rhesus/Aerosol) 27.0 (ED50~pg) 28,494 Bacterium
> Anatoxin-A(s) 50.0 500 Blue-Green Algae
> Microcystin 50.0 994 Blue-Green Algae
> Soman (GD) 64.0 182 Chemical Agent
> Sarin (GB) 100.0 140 Chemical Agent
> Aconitine 100.0 647 Plant (Monkshood)
> T-2 Toxin 1,210.0 466 Fungal Mycotoxin
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### Author:  [@AKAmame](https://boards.straightdope.com/u/AKAmame)
#### Post date: [January 18, 2001, 10:58am UTC](https://boards.straightdope.com/t/toxin/50622/7 "2001-01-18T10:58:30Z")
The toxins produced by _Bacillus anthracis_ are usually produced after the microorganism has entered the victim and started multiplying. There are two common and one rare forms of anthrax, being cutaneous, inhalation and intestinal. Correspondingly, the most common means of transmission are person-to-person or animal-vector-to-person, via a cut or abrasion, inhalation or ingestion. The disorder which _Bacillus anthracis_ causes is an **infection**. _Bacillus anthracis_ may well be the most potent infective agent, but my money would be on smallpox. Or one of the new GM nasties.
I am aware of seven types of _Clostridium botulinum_, A to G, which vary according to their source, (fish, fowl, meat, veggies etc). Their major toxins vary in their effects on humans, with a couple not really affecting humans at all. [British accent] Demn decent of them, what?[/British accent]. Used to be that food-bourne botulism was the major hazard, with wound botulism lagging well behind, and infant botulism a relatively recent discovery. However, changes in food processing hygiene and drug use have changed that.(Lets leave wound and infant botulism out of this discussion - they are whole other threads, and I’ll loose any hope of controlling my parentheses!).
In the good old days, when botulism was a foodbourne illness, the botulinum toxins were almost always produced outside the host under anaerobic (or at the least, locally reducing) conditions, and had their effect when ingested. ‘It’ is not spread by person-to-person or animal-vector-to-person transmission (unless you count someone handing around dud food at a party!). Botulism is an **intoxication**.
As far as I know, one of them thare botulinum toxins is the most powerful toxin known.
Canape anyone?