Seed when castor beans have been ingested by animals. In addition, seeds containing amygdalin—apple, apricot, bitter almond, peach, plum, cherry, quince, and others—when consumed in sufficient amounts, may cause cyanide poisoning. Other seeds that contain poisons include annona, cotton, custard apple, datura, uncooked durian, golden chain, horse-chestnut, larkspur, locoweed, lychee, nectarine, rambutan, rosary pea, sour sop, sugar apple, wisteria, and yew. The seeds of the strychnine tree are also poisonous, containing the poison strychnine. The seeds of many legumes, including the common bean ("Phaseolus vulgaris"), contain proteins called lectins which can cause gastric distress if the beans are eaten without cooking.
Manchineel to an apple, are green or greenish-yellow when ripe. The fruit is poisonous, as is every other part of the tree. All parts of the tree contain strong toxins, some unidentified. Its milky white sap contains phorbol and other skin irritants, producing strong allergic contact dermatitis. Standing beneath the tree during rain will cause blistering of the skin from mere contact with this liquid (even a small drop of rain with the milky substance in it will cause the skin to blister). The sap has also been known to damage the paint on cars. Burning the tree may cause ocular