Castor bean plants are native to the Ethiopian region of tropical east Africa. The seeds of the castor bean are used to produce castor oil. The average castor bean seed contains 35% to 55% oil. The oil is removed from the bean seeds by either pressing or solvent extraction. Castor oil is used in many products. In the U.S., the paint and varnish industry is the single largest market for castor oil. Castor oil is also used for coating fabrics, insulation, cosmetics, skin emollients, hair oils, inks, nylon plastics, greases, and hydraulic fluids.
Ricin is found in all parts of the castor bean plant, but the most concentrated amounts are found in the cake by-product after oil extraction. Ricin is one of the most deadly, naturally occurring poisons known. Ricin received attention when it was used in a subway attack in Japan in 1995 and again when it was sent to a Congressional office in an envelope in February 2004. One non-deadly use for ricin is for medical research where it is being studied for use as a potential treatment for cancer.
Supply - World production of castor-seed beans in the 2005-06 marketing year (the latest data available) rose by +5.7% to a record high of 1.425 million metric tons. The world's largest producer of castor-seed beans by far is India with 64% of world production in 2005-06 at 910,000 metric tons. The second and third largest producers are China with 18% of world production (250,000 metric tons) and Brazil with 12% of world production (162,000 metric tons).
Demand - U.S. consumption of castor oil in 2006-07 rose sharply by +126.4% to a 7-year high of 43.529 million pounds.