Castor Oil: What It Is and Why It's Used

Origin

Castor oil is pressed from the seeds of Ricinus communis, a plant native to East Africa that is now cultivated across tropical regions globally. Its use in medicine, lubrication, and cosmetics predates recorded history in some regions — ancient Egyptian texts reference castor oil applications. The plant also contains ricin, one of the most toxic naturally occurring substances, which is entirely removed during oil processing.

Why It's Used

Castor oil is unusual among vegetable oils in that approximately 90% of its fatty acid content is ricinoleic acid, a hydroxyl fatty acid that gives it distinctive viscosity and polarity. In lip products, this polarity allows it to mix with and adhere to both polar and non-polar pigments, making it an effective pigment-dispersing medium. Its thickness contributes body to formulations.

Elsewhere

Castor oil is a major industrial commodity used in lubricants, hydraulic fluids, paints, coatings, and plastics. It is a feedstock for the production of nylon-11. Hydrogenated castor oil (castor wax) is used in cosmetics separately from the liquid oil.

What the Framework Sees

Question 1.

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