Hippomane Mancinella fruit (c) Wikipedia

This tree is native to North and South America and is found a lot in the Caribbean Islands at the edge of beaches in particular. Manchineel is one of the most poisonous trees in the world. It produces an innocent looking green apple which should not be eaten. In some Caribbean Islands (for example Martinique), they paint a red cross on the tree to warn it is dangerous. The milky sap causes blistering, burns, and inflammation when in contact with the skin, mucous membranes, and conjunctivae. Smoke from the burning wood may injure the eyes. Contact dermatitis from this species is commonly observed in the Caribbean and Central American coastland.

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