Andiroba is a tall rainforest tree that grows up to 40 m high. It is in the same family as mahogany, and it has been called Brazilian mahogany or bastard mahogany due to their similarity. It can be found growing wild throughout the Amazon rainforest, usually on rich soils, in swamps, and in the alluvial flats, marshes, and uplands of the Amazon Basin. It can also be found wild or under cultivation in Brazil in the Islands region, Tocantins, Rio Solimoes, and near the seaside. It is one of the large-leafed trees of the rainforest and can be identified by its large and distinctively textured leaves.

Andiroba wood is soft, yet durable, and much sought by sawmills. It has in the past been shipped to the United States for use in the furniture industry and for other uses. Its durability and impalatability to insects have guaranteed commercial demand for the wood, and as a result, the species has been devastated in all areas near major towns in Amazonia. It could, however, be cultivated easily in the Amazon or other regions of Brazil.

The andiroba tree produces a brown, woody, four-cornered nut, some 3-4 inches across that resembles a chestnut. The nut contains several oil-rich kernels or seeds that average about 63% oil, which is pale yellow in color. Andiroba oil is a sustainable rainforest product that has a long history of use in South America as well as commercial value. A single tree will produce, on average, about 200 kg of nuts annually. Approximately 6 kg of nuts are required to produce 1 kg (about a liter) of andiroba oil using the traditional extraction method. This traditional method is efficient, if somewhat primitive. The seeds are collected from rivers, where they float after being shed by trees or from the forest floor. They are then boiled in a large pot of water, left for some two weeks until they have rotted, and then squeezed (in a primitive press known as a tipiti) to extract the oil. One consequence of this extraction method is that crude andiroba oil is frequently associated with a red coloring that is derived from the skin of the seeds. Because the oil becomes rancid very quickly, it must be used quickly. Local usage is mostly limited to immediate use or to the manufacture of soap or candles.

The indigenous peoples in the Amazon have used andiroba in many ways for centuries, and virtually all parts of the tree, as well as the seed oil are utilized. The Munduruku Indians traditionally used the oil for the mummification of human heads taken as war trophies. The Wayãpi, Palikur, and Creole Indian tribes have used andiroba oil to remove ticks from their scalps, for other skin parasites, and even in the process of tanning animal hides. The indigenous tribes of Northwest Amazonia brew the bark, and sometimes the leaves, into a tea for fevers and intestinal worms; they also apply this tea externally for ulcers, skin parasites, and other skin problems. Indians have also used the oil as a solvent for extracting the plant pigments and colorants with which they paint their skin. Several Indian tribes in the Amazon combine andiroba oil with the reddish-orange pigment extracted from annatto seeds. They rub the oily bright orange paste all over their bodies and even into their hair to protect themselves from biting insects and to repel rain water (to which they are constantly exposed in the rainforest).

Andiroba oil burns well and is used as a natural lamp fuel in the rainforest. In the early 1800s, the street lamps of Belém Brazil were fueled with andiroba oil. Not only does it burn cleanly with little smoke but it also repels mosquitoes, flies, and other pests. Traditional forest dwellers and river people in Brazil called caboclos make a medicinal soap using crude andiroba oil, wood ash, and cocoa skin residue. This soap is especially recommended for the treatment of skin diseases and as an insect repellent. They also apply andiroba oil directly on joints to relieve arthritis pain and mix it with hot water and human milk and drop it into the ear for ear infections. To aid digestion, the bark is soaked in water for a day and 1 cup is taken before meals.

Many of these uses continue today in the Brazilian herbal medicine systems. Andiroba oil is used by Brazilian city dwellers either in pure form or mixed with other oils or natural products. They apply it externally to wounds and bruises, use it as a massage oil and natural insect repellant, and employ it topically for many skin diseases and conditions, including psoriasis. A common natural remedy in Brazil is prepared by soaking 1/4 of a cabacinha (the fruit of Luffa operculata) in 250 ml of hot andiroba oil for several hours. This warm maceration is rubbed into the skin to relieve arthritis and rheumatism and to cauterize wounds. A teaspoon of this preparation is also gargled for sore throats and taken internally for coughs. Andiroba is also still widely used as an insect repellent and for treating insect bites for both people and animals.

The oil is commercially manufactured into anti-inflammatory, antibacterial, anti-arthritic, and insect repellant soaps as well as turned into candles that are sold as natural insect repellents. The oil is also used in Brazil as a furniture polish that is thought to protect wooden furniture from termites and other wood-chewing insects.

Andiroba oil is a rich source of essential fatty acids including oleic, palmitic, stearic, and linoleic acids. It yields up to 65% unsaturated fatty acids and can contain up to 9% linoleic acid. (Linoleic acid has shown in various studies over the years to lower cholesterol levels, reduce blood pressure, and provide anticancer benefits.)

All parts of the andiroba tree (including the oil) tastes very bitter. This bitterness is attributed to a group of terpene chemicals called meliacins, which are very similar to the bitter antimalarial chemicals found in other tropical plants. One of these meliacins, named gedunin, has recently been documented with antiparasitic properties and an antimalarial effect equal to that of quinine.

Chemical analysis of andiroba oil, bark, and leaves has also identified the presence of another group of chemicals called limonoids. The anti-inflammatory and insect repellent properties of andiroba oil are attributed to the presence of these limonoids, including a novel one which has been named andirobin. Another limonoid called epoxyazadiradione is found in andiroba oil; it has been documented with in vitro antitumor effects (neuroblastoma and osteosarcoma cancer cell lines were tested).

Main chemicals found in andiroba include andirobin, arachidic acid, acetoxy-gedunins, epoxyazadiradiones, deacetoxygedunins, hydroxylgedunins, gedunins, hexadecenoic acid, linoleic acid, linolenic acid, oleic acid, palmitic acid, palmitoleic acid, and stearic acid.

Tests of crude andiroba oil by Brazilian scientists have produced evidence of its anti-inflammatory and pain-relieving properties. The bark has also demonstrated in vitro antibacterial activity in another clinical study. Thus far, at least three chemicals found in andiroba have been found to have antiparasitic and/or insecticidal actions. A branch of the Brazilian government has been working with andiroba's insect repellant properties and is soon to produce an insect-repellent product utilizing andiroba oil that will be provided to the military and other government workers who are exposed to mosquitoes and other biting bugs in the forests of Brazil. In 1999, a U.S. patent was filed detailing that andiroba oil, when applied topically, prevented the formation of cellulite through a chemical enzyme-blocking action. (Unfortunately, they reported it didn't have to ability to get rid of existing cellulite). Some of the more recent research has focused on andiroba's anticancerous actions. In 2002, researchers reported that the seed oil could prevent and even reverse cervical dysplasia. Cervical dysplasia is a precancerous condition that can oftentimes develop into cervical cancer. In addition, the leaf, bark, seeds, and flowers have shown some activity against sarcoma cancer cells in vitro, and the crude oil passed a preliminary screening test to predict antitumor activity.

Andiroba oil is well known in Brazil and widely employed to heal many skin conditions and as a natural insect repellant. In the last several years, several andiroba oil products sold in capsules have appeared in Brazilian stores and pharmacies and are recommended for cancer and internal healing. North American practitioners and consumers are just beginning to learn of andiroba's powerful healing properties. Andiroba oil can be applied topically several times daily to rashes, muscle/joint aches and injuries, wounds, insect bites, boils, and ulcers. It can also be used by itself or combined with other oils as a healing and anti-inflammatory massage oil as well as placed in the ears for ear infections. It's also a great natural remedy for ear mites in dogs and cats: just place several drops in the affected ears daily for a week.

Traditional Preparation: For skin conditions, insect bites, and sore muscles and joints, liberally apply the oil topically several times daily. For ear infections, place 2 drops of the oil inside the ears. For internal use, generally 2 ml in a small glass of warm water is taken two or three times daily. This can also be used as a gargle for sore throats.

Drug Interactions: None reported.