Editing Ricin (section)

== Chemical or biological warfare agent ==
===History===
[[File:October 2003 ricin letter metal vial.jpg|thumb|A metal vial containing ricin from the [[2003 ricin letters]]]]
The United States investigated ricin for its military potential during [[World War I]].<ref name="Augerson2000">{{cite report | vauthors = Augerson WS, Spektor DM | publisher = United States Dept. of Defense, Office of the Secretary of Defense, National Defense Research Institute (U.S.) | date = 2000 | title = A Review of the Scientific Literature as it Pertains to Gulf War Illnesses. | volume = 5 |series=Chemical and Biological Warfare Agents | work = Rand Corporation | doi = 10.7249/MR1018.5 | isbn = 978-0-8330-2680-4}}{{page needed|date=April 2013}}</ref> At that time it was being considered for use either as a toxic dust or as a coating for bullets and [[Shrapnel shell|shrapnel]]. The dust cloud concept could not be adequately developed, and the coated bullet/shrapnel concept would violate the [[Hague Conventions (1899 and 1907)|Hague Convention of 1899]] (adopted in U.S. law at 32 [[United States Statutes at Large|Stat.]] 1903), specifically Annex §2, Ch.1, Article 23, stating "...&nbsp;it is especially prohibited&nbsp;... [t]o employ poison or poisoned arms".<ref>{{cite web|url=http://avalon.law.yale.edu/19th_century/hague02.asp#art23 |title=The Avalon Project&nbsp;– Laws of War: Laws and Customs of War on Land (Hague II); July 29, 1899 |publisher=Avalon.law.yale.edu |access-date=1 September 2010}}</ref>

During [[World War II]] the United States and Canada studied ricin in [[cluster bomb]]s.<ref name="Gupta_2009">{{cite book | vauthors = Gupta R | title = Handbook of Toxicology of Chemical Warfare Agents | publisher = Academic Press | location = Boston | year = 2009 | isbn = 978-0-12-374484-5 }}{{page needed|date=April 2013}}</ref> Though there were plans for mass production and several field trials with different bomblet concepts, the end conclusion was that it was no more economical than using [[phosgene]]. This conclusion was based on comparison of the final weapons, rather than ricin's toxicity ([[LD50|LCt<sub>50</sub>]] ~10&nbsp;mg/min·m<sup>3</sup>).{{Citation needed|date=January 2024}} Ricin was given the [[chemical weapon designation|military symbol]] '''W''' or later '''WA'''.{{Citation needed|date=January 2024}}  Interest in it continued for a short period after World War II, but soon subsided when the [[Chemical Corps|US Army Chemical Corps]] began a program to weaponize [[sarin]].<ref name="Romano_2007">{{cite book | vauthors = Romano Jr JA, Salem M, Lukey BJ | title = Chemical Warfare Agents: Chemistry, Pharmacology, Toxicology, and Therapeutics, Second Edition | publisher = CRC Press | year = 2007 | pages = 437 | isbn = 978-1-4200-4662-5 }}</ref>

The [[Soviet Union]] possessed weaponized ricin. The [[KGB]] developed weapons using ricin which were used outside the [[Soviet Bloc|Soviet bloc]], most famously in the [[Georgi Markov|Markov assassination]].<ref>{{cite book |last1=Cummings |first1=Richard H. |title=Cold War Radio: The Dangerous History of American Broadcasting in Europe, 1950-1989 |date=22 April 2009 |publisher=McFarland |isbn=978-0-7864-5300-9 |pages=67–70 |url=https://books.google.com/books?id=Kfl-8vMB0jEC |language=en}}</ref><ref>{{cite news| last=Edwards | first=Richard | title=Poison-tip umbrella assassination of Georgi Markov reinvestigated | newspaper=The Telegraph | date=19 June 2008 | url=https://www.telegraph.co.uk/news/2158765/Poison-tip-umbrella-assassination-of-Georgi-Markov-reinvestigated.html|archive-url=https://ghostarchive.org/archive/20220112/https://www.telegraph.co.uk/news/2158765/Poison-tip-umbrella-assassination-of-Georgi-Markov-reinvestigated.html |archive-date=12 January 2022|url-status=live }}</ref>

===Control===
In spite of ricin's extreme [[toxicity]] and utility as an agent of chemical/biological warfare, production of the toxin is difficult to limit. The [[castor bean]] plant from which ricin is derived is a common [[ornamental plant|ornamental]] and can be grown at home without any special care.

Under both the 1972 [[Biological Weapons Convention]] and the 1997 [[Chemical Weapons Convention]], ricin is listed as a [[List of Schedule 1 substances (CWC)|schedule 1 controlled substance]]. Despite this, more than {{convert|1|e6MT|ST|abbr=off}} of castor beans are processed each year, and approximately 5% of the total is rendered into a waste containing negligible concentrations of undenatured ricin toxin.<ref name="http://www.ansci.cornell.edu/plants/toxicagents/ricin.html">{{cite web|url=http://www.ansci.cornell.edu/plants/toxicagents/ricin.html |title=Cornell University Department of Animal Science |publisher=Ansci.cornell.edu |access-date=7 May 2012}}</ref>

Ricin is several orders of magnitude less toxic than [[botulinum]] or [[tetanus toxin]], but the latter are harder to come by. Compared to botulinum or [[anthrax]] as [[biological weapon]]s or [[chemical weapon]]s, the quantity of ricin required to achieve LD<sub>50</sub> over a large geographic area is significantly more than an agent such as anthrax (tons of ricin vs. only kilogram quantities of anthrax).<ref name="pmid10458957">{{cite journal | vauthors = Kortepeter MG, Parker GW | title = Potential biological weapons threats | journal = Emerging Infectious Diseases | volume = 5 | issue = 4 | pages = 523–527 | year = 1999 | pmid = 10458957 | pmc = 2627749 | doi = 10.3201/eid0504.990411 }}</ref> Ricin is easy to produce, but is not as practical or likely to cause as many casualties as other agents.<ref name="Schep"/> Ricin is easily denatured by temperatures over {{convert|80|C|F}} meaning many methods of deploying ricin would generate enough heat to denature it.<ref name="Levy-2011" /> Once deployed, an area contaminated with ricin remains dangerous until the bonds between chain A or B have been broken, a process that takes two or three days.<ref name="Harkup-2015" /> In contrast, anthrax [[endospore|spore]]s may remain lethal for decades. [[Jan van Aken (Politician)|Jan van Aken]], a German expert on biological weapons, explained in a report for [[The Sunshine Project]] that [[Al Qaeda]]'s experiments with ricin suggest their inability to produce [[botulinum toxin|botulinum]] or anthrax.<ref name="vanaken2001">{{cite web | vauthors = van Aken J | year = 2001 | archive-url = https://archive.today/20130108235747/http://www.sunshine-project.org/publications/bk/bk7en.html | archive-date = 8 January 2013 | url = http://www.sunshine-project.org/publications/bk/bk7en.html | title = Biological Weapons: Research Projects of the German Army | work = Backgrounder Series No. 7 | publisher = [[The Sunshine Project]] | url-status = dead }}</ref>