Avocado tree (Persea americana) originates from Central America and is
now cultivated in tropical and subtropical regions for the production of avocado
fruits. A fatty oil present in the pulp of the fruit is a much valued ingredient
The active ingredient, termed persin (a toxic fatty acid derivative), from
avocado leaves has been identified as
(Z,Z)-1-(acetyloxy)-2-hydroxy-12,15-heneicosadien-4-one. Persin is generally
harmless to humans.
Birds, goats, horses, sheep, cats, cattle, rodents, fish, and dogs frequently
get poisoned while feeding on or chewing avocado leaves, bark, skin, or pit. The
main symptoms of poisoning are difficult breathing, abnormally high and
irregular heart rate, and accumulation of fluids in the lungs, abdomen, and
around the heart. In horses, persin causes equine colic which, if left
untreated, leads to death.