Borneol is a naturally occurring organic compound, an alcohol in the terpene family with the chemical formula C10H18O. It is derived from the essential oils of several species of plants and trees native to southeast Asia and Borneo, hence the name. The same word is also used to describe mixtures used in traditional Chinese medicine that contain the compound itself. These mixtures are sometimes known as Borneo or borneol camphor.
The association with camphor occurs because this substance is similar to camphor, and in fact, can be chemically converted through oxidation to the compound from which camphor is derived. Synthetic borneol, conversely, can be produced by breaking down camphor. It is also used in other chemical processes as the basis or the catalyst for synthesis of other compounds.
Like many other chemical compounds, borneol has two separate forms, or isomers, which are chemically identical in terms of formula, but differ in arrangement of the individual atoms. One of these two forms is found in nature, but the other is synthetic. The naturally occurring type causes light that is passed through its crystals to bend. The synthetic form does not have this effect. Another isomer of borneol, known as isoborneol is also used in certain processes in organic chemistry.
In its pure form, borneol is a whitish, crystalline substance made up small irregular crystals. Its Chinese name is derived from the Chinese words for "ice" and "slice". Even though used in many traditional Chinese medicines and in some clinical applications in other types of medicine, pure borneol is an irritant to skin, eyes, and respiratory systems and is classified in the United States as mildly toxic and potentially harmful if swallowed.
Besides its uses in medicine, borneol is used in other ways as well, particularly in the manufacture of perfumes and other scent products. Despite the possibility of harmful effects due to exposure or consumption, it is sometimes used, albeit in very small amounts, as a flavoring and in over the counter medicines, particularly in Asia. Some of these products may be available in other parts of the world as well. In the United States, borneol is not approved by the Food and Drug Administration (FDA) for use as a medicine but is not prohibited as an ingredient, and products containing it are labeled as "herbal supplements" or "dietary supplements."