EUPHORBIACEAE

The Euphorbiaceae or spurge family comprises some 7500+ species of herbs, shrubs, trees and succulents found in the tropical, temperate, and arid regions of the world. Euphorbiaceae usually exhibit simple alternate leaves, small inconspicuous flowers, and fruits that are 3-5 lobed capsules, which burst explosively to disperse seeds (dehiscent). Most Euphorbiaceae exude milky latex that is toxic and irritating. Several species are of economic importance. The rubber tree (Hevia brasiliensis) is widely cultivated for its latex. The poisonous but edible tuber of cassava (Manihot esculenta) is a staple source of food in developing countries. 

 

Euphorbiaceae often elaborate diterpene toxins called phorbol esters, which are corrosive and tumour promoting (does not cause cancer, but enhances the cancer-causing effects of cancer-causing substances). A variation of phorbol ester called resiniferoid is the most pungent (spicy) substance known to humans. The resiniferoid is two to three orders of magnitude more potent than the world’s hottest pepper. It is currently investigated as a drug to treat chronic pain and kidney diseases. Several Euphorbiaceae species like the castor-oil plant (Ricinus communis) and Jatropha spp. produce extremely toxic proteins in their seed called toxalbumins, which inhibit cells from making life-sustaining proteins. The toxalbumin ricin has gained worldwide infamy as a  bioweapon capable of mass destruction. However, the lethal attributes of castor-oil plant is far too greatly exaggerated by media. Other infamously poisonous Euphorbiacea include the Manchineel tree (Hippomane mancinella), blind-your-eye mangrove (Excoecaria agallocha), purging croton (Croton tiglium), Gifboom poison tree (Euphorbia virosa) and Barbados nut (Jatropha curcas). 

 

The castor oil plant (Ricinus communis) is regarded by many as the most poisonous plant in the world. This is not true. Note: The male flowers are borne on top of the female to discourage self-fertilisation.

Ricinus communis, young leaf.

Ricinus communis, foliage.

Purging croton (Croton tiglium).

The seed of the purging croton or Ba-Dou 巴豆 is dried and roasted over fire to produce a tradition Chinese medicine. In ancient China, Ba-Dou is used by criminals to poison horses and render them lame. Ten drops of croton oil is fatal to an adult human

The blind-your-eye mangrove (Excoecaria agallocha) is infamous around Southeast Asia and Australia. It exudes corrosive latex that causes severe burn to all parts of the human body, particularly the eyes. Even James Cook's sailors were blinded by this tree. The burning wood of E. agallocha produces a pleasant fragrance, inhaling it is not recommended!

Excoecaria agallocha, tri-lobed seedpods.

The dynamite tree (Hura crepitans) is famous for its explosive seedpod. This South American species is so toxic, it used by tribesmen to kill adult anaconda snake. 

 

Hura crepitans, seedpod

Physicnut (Jatropha gossypiifolia)

Peregrina (Jatropha integerrima)

Buddha belly plant (Jatropha podagrica)

The toxin of the resin spurge (Euphorbia resinifera), resiniferatoxin is the most spicy substance known to science. It measures a whopping 16 billion Scoville units! The resin spurge is native to Morocco,  it has evolved cactus-like features to survive the dry and arid environment.

The pencil 'cactus' (Euphorbia tirucalli) is widely cultivated as an ornamental plant. Instances of eye injury caused by E. tirucalli latex are well-documented.

The candle plant (Euphorbia poissonii) is the second most spicy plant in the world. Its toxin, tinyatoxin is about half as potent as resiniferatoxin. This species is native to Nigeria. Locals use its latex to deter and poison pest animals. The variegated form of E. poissonii is widely cultivated as an ornamental succulent.