poisonous seeds (Ricinus)

mystic mystic at lcc.net
Thu Mar 26 01:37:59 EST 1998

> David Kramer wrote
> ----------------------------------
> Several sources (e.g., Magic and Medicine of Plants) report that castor
> beans (Ricinus) are poisonous. Years ago at Indiana University we
> dissected castor beans in general botany labs as an example of a seed in
> which the endosperm is not absorbed until the time of germination ( in
> contrast to garden bean, etc.). We stopped doing that when we were told
> that the poison in the seeds could even be absorbed through the skin!
> Before you ask students to dissect them, you might want to investigate this
> further.
> Please post what you find to Plant-Ed. I often see this plant in botanical
> gardens and other public plantings as an ornamental. Granted it is very
> attractive but I always wonder why they would be put in a public place
> where children might ingest the seeds. If someone will tell me they are
> not poisonous, I'll stop worrying!
> Dr. David W. Kramer
> Department of Plant Biology
> Ohio State University at Mansfield
> 1680 University Drive
> Mansfield, OH 44906-1547
> (419) 755-4344 FAX: (419) 755-4367
> e-mail: kramer.8 at osu.edu
> ---------------------------------------
> The seeds of Ricinus communis are extremely poisonous. As I recall, about
> 11 seeds are reputed to constitute a fatal dose and certainly the purified
> toxalbumin (Ricin), which was used to kill the Bulgarian dissident Georgi
> Markow in London,is second only to botulin in terms of toxicity. In
> addition the seeds contain an allergen (famous in some botanical circles,
> for its dramatic effects on those unlucky enough to be affected by it) and
> a poisonous alkaloid, seemingly thrown in for good measure. Keep worrying!
> David Walker

The seeds aren't the only parts of Ricinus that are poisonous.  ALL
of this plant are toxic to some degree.  
Strange to say, the common poinsettia, which is often believed to
be poisonous, is not.
In addition, another increasingly popular ornamental, Datura (or angel
trumpet), is also very, very poisonous.  All parts of it contain
alkaloid toxins, and it, too, is sold as an ornamental with no warning
about the 
possible dangers to small children.  Most pets wouldn't touch the
stuff, but ruminants might.  It is commonly known as 'locoweed'.

Yellow Jessamine, another popular ornamental, is also rather toxic.


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