Editing Ricinus (section)

== Allergenicity and toxicity ==
''Ricinus'' is extremely allergenic, and has an [[OPALS (Ogren Plant Allergy Scale)|OPALS]] allergy scale rating of 10 out of 10. The plant is also a very strong trigger for asthma, and allergies to ''Ricinus'' are commonplace and severe.<ref name="Ogren">{{cite book |last1=Ogren |first1=Thomas |title=The Allergy-Fighting Garden |date=2015 |publisher=Ten Speed Press |isbn=978-1-60774-491-7 |location=Berkeley, CA |pages=184–185}}</ref>

The castor oil plant produces abundant amounts of very light pollen, which easily become airborne and can be inhaled into the lungs, triggering allergic reactions. The sap of the plant causes skin rashes. People who are allergic to the plant can also develop rashes from touching the leaves, flowers, or seeds. They can also have cross-allergic reactions to [[latex]] sap from the related ''[[Hevea brasiliensis]]'' plant.<ref name="Ogren" />

The toxicity of raw castor beans is due to the presence of [[ricin]]. Although the lethal dose in adults is considered to be four to eight seeds, reports of actual poisoning are relatively rare.<ref>{{cite journal |vauthors=Wedin GP, Neal JS, Everson GW, Krenzelok EP |date=May 1986 |title=Castor bean poisoning |journal=Am J Emerg Med |volume=4 |issue=3 |pages=259–61 |doi=10.1016/0735-6757(86)90080-X |pmid=3964368}}</ref> According to the ''[[Guinness World Records]]'', this is the world's most poisonous common plant.<ref>{{cite book |title=Guinness World Records 2017 |date=2016 |publisher=Guinness World Records Limited |location=London, UK |page=43}}</ref>

If ricin is ingested, symptoms commonly begin within two to four hours, but may be delayed by up to 36 hours. These include a burning sensation in mouth and throat, abdominal pain, purging and bloody diarrhea. Within several days there is severe dehydration, a drop in blood pressure and a decrease in urine. Unless treated, death can be expected to occur within 3–5 days; however, in most cases a full recovery can be made.<ref name="Soto-Blanco">{{cite journal |vauthors=Soto-Blanco B, Sinhorini IL, Gorniak SL, Schumaher-Henrique B |date=June 2002 |title=''Ricinus communis'' cake poisoning in a dog |journal=Vet Hum Toxicol |volume=44 |issue=3 |pages=155–6 |pmid=12046967}}</ref><ref>''Ricinus communis'' (Castor bean)—[[Cornell University]] 2008. {{cite web |title=Castorbean |url=http://www.ansci.cornell.edu/plants/castorbean.html |url-status=dead |archive-url=https://web.archive.org/web/19980508072815/http://www.ansci.cornell.edu/plants/castorbean.html |archive-date=8 May 1998}}</ref>

Poisoning occurs when animals, including humans, ingest broken castor beans or break the [[seed]] by chewing: intact seeds may pass through the digestive tract without releasing the toxin.<ref name="Soto-Blanco" /> The toxin provides the castor oil plant with some degree of natural protection from insect pests such as [[aphid]]s. Ricin has been investigated for its potential use as an [[insecticide]].<ref name="Ombrello">[http://faculty.ucc.edu/biology-ombrello/POW/castor_bean.htm Union County College: Biology: Plant of the Week: Castor Bean Plant] {{webarchive|url=https://web.archive.org/web/20130524162501/http://faculty.ucc.edu/biology-ombrello/POW/castor_bean.htm|date=24 May 2013}}</ref>

Commercially available cold-pressed castor oil is not toxic to humans in normal doses, whether internal or external.<ref>{{cite journal |author=Irwin R |date=March 1982 |title=NTP technical report on the toxicity studies of Castor Oil (CAS No. 8001-79-4) In F344/N Rats And B6C3F1 Mice (Dosed Feed Studies) |journal=Toxic Rep Ser |volume=12 |pages=1–B5 |pmid=12209174}}</ref>