The composition of the oil will depend on the species, region grown, age of tree,[2] and possibly the season of harvest and details of the extraction process used.
Due to its highly coveted fragrance, the essential oil produced from sandalwood is often used in aromatherapy, and is also added to soaps and cosmetics. It is used in Ayurvedic medicine for the treatment of both somatic and mental disorders, including common colds, bronchitis, fever, urinary tract infections, and inflammation.[5] A study investigating the effects of inhalation of East Indian sandalwood oil and its main compound, α-santalol, on human physiological parameters found that the compounds elevated pulse rate, skin conductance, and systolic blood pressure.[5]
The oil is distilled from the wood of the entire tree including stump and roots.[6] Australian sandalwood (S. spicatum) is unique in that the white sapwood does not require removal before distilling the oil, while Indian Sandalwood (S. album) does require removal of the sapwood prior to distillation.[7]
Fragrance
Sandalwood oil is used extensively for its woody-floral scent. It pairs well with other wood or floral scents such as violet, rose, tuberose, clove, and oakmoss.[8] But since the wood is so rare and expensive, cosmetic companies are now trying to find synthetic substitutes to try to imitate the structure and scent of sandalwood.
There are several synthetic odorants with odor similar to sandalwood oil, used as lower-cost alternatives for perfumes, emollients, and skin cleaning agents. Common synthetic substitutes include Sandalore, Bacdanlol, Ebanol, Florsantol, and Sandaxol.[9]
Two of these, Sandalore and Brahmanol, have been found to be agonists of the cutaneous olfactory receptorOR2AT4, with potential therapeutic benefits for wound healing. Natural sandalwood oil, and other synthetic sandalwood odorants, did not have the same effect.[10][11]
Safety
There hasn't been extensive research conducted on the safety of sandalwood oil. But because there haven't been any significant adverse effects documented in scientific literature, it continues to be used cosmetically and in food. A few studies were found to identify sandalwood oil's potential toxic effects, but it was determined to be safe at the present levels that the oil is used in food as flavorings.
^Krotz A, Helmchen G (1994). "Total Syntheses, Optical Rotations and Fragrance Properties of Sandalwood Constituents: (−)-(Z)- and (−)-(E)-β-Santalol and Their Enantiomers, ent-β-Santalene". Liebigs Ann Chem. 1994 (6): 601–609. doi:10.1002/jlac.199419940610.
^Burdock, George A; Carabin, Ioana G (Summer 2007). "Safety assessment of sandalwood oil". Food and Chemical Toxicology. 46 (2): 421–432. doi:10.1016/j.fct.2007.09.092. PMID17980948.