Castor oil is a vegetable oil pressed from castor beans. It is a colourless or pale yellow liquid with a distinct taste and odor. Its boiling point is 313 °C (595 °F) and its density is 0.961 g/cm3. It includes a mixture of triglycerides in which about 90% of fatty acids are ricinoleates. Oleic acid and linoleic acid are the other significant components. Castor oil and its derivatives are used in the manufacturing of soaps, lubricants, hydraulic and brake fluids, paints, dyes, coatings, inks, cold-resistant plastics, waxes and polishes, nylon, and perfumes. Etymology
The name probably comes from a confusion between the Ricinus plant that produces it and another plant, the Vitex agnus-castus. An alternative etymology, though, suggests that it was used as a replacement for castoreum. Composition
Castor oil is well known as a source of ricinoleic acid, a monounsaturated, 18-carbon fatty acid. Among fatty acids, ricinoleic acid is unusual in that it has a hydroxyl functional group on the 12th carbon atom. This functional group causes ricinoleic acid (and castor oil) to be more polar than most fats. The chemical reactivity of the alcohol group also allows chemical derivatization that is not possible with most other seed oils. Because of its ricinoleic acid content, castor oil is a valuable chemical in feedstocks, commanding a higher price than other seed oils. As an example, in July 2007, Indian castor oil sold for about US$0.90/kg ($0.41/lb), whereas U.S. soybean, sunflower, and canola oils sold for about $0.30/kg ($0.14/lb).
Punishment
Some parents punished children with a dose of castor oil. Physicians recommended against the practice because they did not want medicines associated with punishment.A heavy dose of castor oil could be used as a humiliating punishment for adults. Colonial officials used it in the British Raj (India) to deal with recalcitrant servants. Belgian military officials prescribed heavy doses of castor oil in Belgian Congo as a punishment for being too sick to work.The most famous use as punishment came in Fascist Italy under Benito Mussolini. It was a favorite tool used by the Blackshirts to intimidate and humiliate their opponents. Political dissidents were force-fed large quantities of castor oil by Fascist squads. This technique was said to have been originated by Gabriele DAnnunzio or Italo Balbo. Victims of this treatment did sometimes die, as the dehydrating effects of the oil-induced diarrhea often complicated their recovery from the nightstick beatings they also received along with the castor oil; however, even those victims who survived had to bear the humiliation of the laxative effects resulting from excessive consumption of the oil. Safety
The castor seed contains ricin, a toxic lectin. Heating during the oil extraction process denatures and deactivates the lectin. Harvesting castor beans, though, may not be without risk. The International Castor Oil Association FAQ document states that castor beans contain an allergenic compound called CB1A. This chemical is described as being virtually nontoxic, but has the capacity to affect people with hypersensitivity. The allergen may be neutralized by treatment with a variety of alkaline agents.