What is it?
A fatty oil obtained from the seed kernels of the Western Australian sandalwood tree, Santalum spicatum. It is not the same as sandalwood essential oil, the fragrant oil distilled from the tree’s wood. Oil makes up about half the weight of the kernels, and 30 to 35 percent of its fatty acids are ximenynic acid, an uncommon fatty acid. In cosmetics it is used as a skin-conditioning ingredient.
Key information
- Sandalwood seed oil is a fixed (fatty) oil, not an essential oil or fragrance ingredient.
- Between 30 and 35 percent of its fatty acids are ximenynic acid.
- The EU's CosIng database lists it as a skin-conditioning ingredient with no restrictions.
- Sandalwood essential oil, distilled from the wood of the same tree, is a different ingredient and a known fragrance allergen.
More information
Western Australian sandalwood is best known for its wood, which is distilled into a sandalwood essential oil. The seed oil comes from a different part of the tree, the seed kernels, which are about 50 percent oil. Scientists have studied it mainly because of ximenynic acid, which makes up 30 to 35 percent of its fatty acids. In a 1997 study, mice fed a diet containing 15 percent sandalwood seed oil for eight weeks carried only small amounts of ximenynic acid in their liver and fat tissue and none in the brain, and the researchers suggested that the body converts much of it to oleic acid.
We found no dedicated safety review of the seed oil by an expert panel such as the Cosmetic Ingredient Review (CIR) or the EU’s Scientific Committee on Consumer Safety (SCCS), and published data on its effects on skin are limited. The EU’s CosIng database lists it as a skin-conditioning ingredient, with no restrictions and no SCCS opinions. We found no reports of skin irritation or allergy linked to it.
Don’t confuse it with sandalwood essential oil. The SCCS describes Australian sandalwood wood oil as about 75 percent santalols and 10 percent farnesol, and regards it as an established contact allergen because of the santalols. On labels, the seed oil appears as Santalum Spicatum Seed Oil, while the essential oil is listed under wood oil names or included in “fragrance” or “parfum.”
Sources: European Commission CosIng: Santalum Spicatum Seed Oil; Lipids (1997): Dietary sandalwood seed oil modifies fatty acid composition of mouse adipose tissue, brain, and liver; SCCS: Opinion on fragrance allergens in cosmetic products (2012)
