What Are Castor Beans Used For?

Castor beans are usually processed into a yellowish, odorless oil that has many applications.

The fruit of the castor bean plant (Ricinus communis) contains volatile oils which have a huge variety of uses in industry and commerce. In their raw, unprocessed state, castor beans contain one of the most toxic compounds known to science, ricin. The beans, with their mottled appearance which resemble blood-engorged ticks, should never be ingested as even one or two beans can cause swift intoxication and death. However, the thick, colorless and odorless oil is valuable as a beauty aid, lubricant and raw material for other industrial uses.

Varnish and Protectant

The oil of the castor bean is odorless, quick-drying and water-resistant, which makes it a superb protectant. This oil is used alongside other plant-based oil varnishes like linseed and tung oil. The dehydrated oil is also used to coat the surfaces of upholstered fabrics, leathers, weaponry, insulation and food containers.

Nylon Ingredient

Castor bean oil is a primary ingredient required for the manufacture of nylon; each ton of nylon produced requires roughly 3 tons of castor bean oil.

Motor Oils

Castor bean oil's ability to remain viscous even at high temperatures makes it an effective industrial lubricant, especially in motors and fast-moving machinery. One popular brand of engine oil even derives its brand name from the plant; castor oil is the main ingredient in Castrol motor oil.

Synthetic Flavors

Castor bean oil, when broken down in a chemical process, produces aromatic esters which are used to create artificial fruit flavors--including jasmine, apricot, peach, plum, rose, banana and lemon. Ironically, raw castor oil itself is renowned for its bad stench.

Laxative and Purgative

Castor oil has long been used as a laxative and purgative to clear the digestive tract. Taken by the spoonful, castor oil induces vomiting and was very popular during the 18th and 19th centuries, though it is rarely used in modern Western society. According to sources cited by Purdue University researchers, castor oil has also been found in Egyptian tombs, indicating its medicinal use even in ancient times.


After the oils have been removed from the castor bean, the seed hulls are compacted into "cakes" which are used as high-quality fertilizer.

As a Beauty Aid

Castor bean oil and wax are used in many soaps, lotions and oils, and are also ingredients in some products used to treat skin rashes, sunburn and open sores. Some hair products also incorporate castor bean oil in their ingredient lists.

Miscellaneous Uses

The wax and oils from the castor bean are also used in the manufacture of inks, crayons, contraceptives and pesticides. According to a paper by J.M. Lord of the University of Warwick, the plant's toxic compound of ricin is under study by medical researchers for use as a potential cancer-fighting agent.

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