Explore Plants

Share

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
    
 

Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.

rate this answer
Not Yet Rated

Saturday - August 24, 2013

From: Richmond, TX
Region: Southwest
Topic: Non-Natives, Poisonous Plants
Title: Does non-native Crown of Thorns cause cancer?
Answered by: Nan Hampton

QUESTION:

Does the plant, Corona De Cristo (Crown of thorns) cause cancer?

ANSWER:

First of all, the focus and expertise of the Lady Bird Johnson Wildflower Center is with plants native to North America.  Euphorbia milii (Crown of Thorns) is native to Madagascar and, thus, is really out of our purview.  However, I can point you to several internet sources where you can find out more about it.

Poisonous Plants of North Carolina lists it as being mildly toxic and, according to the University of Florida Miami-Dade Cooperative Extension Service:

"As with other euphorbs, E. milii produces copious quantities of poisonous milky sap that can cause skin irritation, and contains tumor promoting chemicals (diterpene esters).  It would be best to wear gloves when handling the plants, and to wash off any sap that gets on your skin."

Here is more information from Union County College in New Jersey.

There are rumors about the plant having cancer causing abilities and several of the sites listed above note that the sap has chemicals that are known tumor promoters.  However, a study testing the sap on mice skin did not produce tumors.  [Delgado, I. F. et al.  2003. Absence of tumor promoting activity of Euphorbia milii latex on the mouse back skin.  Toxicol. Lett. 2003 Nov 30;145(2):175-80.]

If I were you, I would use caution in handling the plant and, as the advice from Miami-Dade Cooperative Extension Service recommends—wear gloves and wash off any sap that gets on your skin.

 

More Poisonous Plants Questions

Are leaves of banana trees poisonous?
August 10, 2008 - are the leaves of banana trees poisonous? the tree will be in a preschool classroom How do i care for the tree?
view the full question and answer

Is Purple Hopseed poisonous to dogs?
September 03, 2011 - Is the Purple Hopseed plant safe for dogs? We would like to plant a hedge of the purple hopseed at my parents home. They are elderly and have a small (8lb.) dog that they just love so much..I would ...
view the full question and answer

Removing poison ivy in Cuba MO
August 27, 2011 - I bought a home with a huge bed of hybrid iris but the bed is thick with poison ivy. If I cover myself head to toe to prevent getting it is there a way to clean the tubers so they will not be poison? ...
view the full question and answer

Lantana poisonous to people, animals
May 07, 2008 - Mr. Smarty Plants, I read your response to the woman with the cow eating her plants over her neighbors fence. Just so you know- Lantana is poisionous. To humans and cattle. You recommended it as a...
view the full question and answer

Spots on leaves of sevenleaf creeper in Austin
November 14, 2009 - Have 3 seven leaf creepers that are planted in mostly shade. In Sept & Oct 2009 all 3 plants had dried up leaves which fell off; however, all three plants grew new leaves when we got rain and are com...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.