The castor bean plant looks like a giant houseplant, with huge star-shaped leaves and clusters of spiky pods. But hidden inside each bean is one of the deadliest natural poisons on Earth, called ricin. A small amount of pure ricin can be dangerous, which is why scientists call it one of the most toxic substances found in nature.
What’s weird is that humans grow castor bean plants on purpose, all around the world. The seeds are pressed to make castor oil, which is used in soaps, lipsticks, paints, plastics and even bicycle chain lubricant. The pressing process safely removes the ricin, leaving harmless, useful oil behind.
Castor plants are native to East Africa but now grow almost everywhere warm. Some gardeners even plant them for their dramatic leaves, although they have to be careful around pets and kids. The plant is a strange double act - the source of one of nature’s worst poisons and one of its most useful oils, both from the same bean.
